@@ -1,23 +0,0 @@ | |||
name: HQC_128_1_CCA2 | |||
type: kem | |||
claimed-nist-level: 1 | |||
claimed-security: IND-CCA2 | |||
length-public-key: 3125 | |||
length-ciphertext: 6234 | |||
length-secret-key: 3165 | |||
length-shared-secret: 64 | |||
nistkat-sha256: 29b6545c85a9aaf75572f112b4d4cf9078c716147f84072c4efe4ce5160f18e0 | |||
principal-submitters: | |||
- Carlos Aguilar Melchor | |||
- Nicolas Aragon | |||
- Slim Bettaieb | |||
- Loïc Bidoux | |||
- Olivier Blazy | |||
- Jean-Christophe Deneuville | |||
- Philippe Gaborit | |||
- Edoardo Persichetti | |||
- Gilles Zémor | |||
auxiliary-submitters: [] | |||
implementations: | |||
- name: leaktime | |||
version: https://pqc-hqc.org/doc/hqc-reference-implementation_2019-08-24.zip |
@@ -1 +0,0 @@ | |||
Public domain |
@@ -1,19 +0,0 @@ | |||
# This Makefile can be used with GNU Make or BSD Make | |||
LIB=libhqc-128-1-cca2_leaktime.a | |||
HEADERS=api.h bch.h fft.h gf.h gf2x.h hqc.h parameters.h parsing.h repetition.h tensor.h vector.h util.h | |||
OBJECTS=bch.o fft.o gf.o gf2x.o hqc.o kem.o parsing.o repetition.o tensor.o vector.o util.o | |||
CFLAGS=-O3 -Wall -Wextra -Wpedantic -Wvla -Werror -Wmissing-prototypes -Wredundant-decls -std=c99 -I../../../common $(EXTRAFLAGS) | |||
all: $(LIB) | |||
%.o: %.c $(HEADERS) | |||
$(CC) $(CFLAGS) -c -o $@ $< | |||
$(LIB): $(OBJECTS) | |||
$(AR) -r $@ $(OBJECTS) | |||
clean: | |||
$(RM) $(OBJECTS) | |||
$(RM) $(LIB) |
@@ -1,23 +0,0 @@ | |||
# This Makefile can be used with Microsoft Visual Studio's nmake using the command: | |||
# nmake /f Makefile.Microsoft_nmake | |||
LIBRARY=libhqc-128-1-cca2_leaktime.lib | |||
OBJECTS=bch.obj fft.obj gf.obj gf2x.obj hqc.obj kem.obj parsing.obj repetition.obj tensor.obj vector.obj util.obj | |||
# We ignore warning C4127: we sometimes use a conditional that depending | |||
# on the parameters results in a case where if (const) is the case. | |||
# The compiler should just optimise this away, but on MSVC we get | |||
# a compiler complaint. | |||
CFLAGS=/nologo /O2 /I ..\..\..\common /W4 /WX /wd4127 | |||
all: $(LIBRARY) | |||
# Make sure objects are recompiled if headers change. | |||
$(OBJECTS): *.h | |||
$(LIBRARY): $(OBJECTS) | |||
LIB.EXE /NOLOGO /WX /OUT:$@ $** | |||
clean: | |||
-DEL $(OBJECTS) | |||
-DEL $(LIBRARY) |
@@ -1,25 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1281CCA2_LEAKTIME_API_H | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_API_H | |||
/** | |||
* \file api.h | |||
* \brief NIST KEM API used by the HQC_KEM IND-CCA2 scheme | |||
*/ | |||
#include <stdint.h> | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_CRYPTO_ALGNAME "HQC_128_1_CCA2" | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_CRYPTO_SECRETKEYBYTES 3165 | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_CRYPTO_PUBLICKEYBYTES 3125 | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_CRYPTO_BYTES 64 | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_CRYPTO_CIPHERTEXTBYTES 6234 | |||
// As a technicality, the public key is appended to the secret key in order to respect the NIST API. | |||
// Without this constraint, CRYPTO_SECRETKEYBYTES would be defined as 32 | |||
int PQCLEAN_HQC1281CCA2_LEAKTIME_crypto_kem_keypair(uint8_t *pk, uint8_t *sk); | |||
int PQCLEAN_HQC1281CCA2_LEAKTIME_crypto_kem_enc(uint8_t *ct, uint8_t *ss, const uint8_t *pk); | |||
int PQCLEAN_HQC1281CCA2_LEAKTIME_crypto_kem_dec(uint8_t *ss, const uint8_t *ct, const uint8_t *sk); | |||
#endif |
@@ -1,295 +0,0 @@ | |||
/** | |||
* @file bch.c | |||
* Constant time implementation of BCH codes | |||
*/ | |||
#include "bch.h" | |||
#include "fft.h" | |||
#include "gf.h" | |||
#include "parameters.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
static void unpack_message(uint8_t *message_unpacked, const uint8_t *message); | |||
static void lfsr_encode(uint8_t *codeword, const uint8_t *message); | |||
static void pack_codeword(uint8_t *codeword, const uint8_t *codeword_unpacked); | |||
static size_t compute_elp(uint16_t *sigma, const uint16_t *syndromes); | |||
static void message_from_codeword(uint8_t *message, const uint8_t *codeword); | |||
static void compute_syndromes(uint16_t *syndromes, const uint8_t *vector); | |||
static void compute_roots(uint8_t *error, const uint16_t *sigma); | |||
/** | |||
* @brief Unpacks the message message to the array message_unpacked where each byte stores a bit of the message | |||
* | |||
* @param[out] message_unpacked Array of VEC_K_SIZE_BYTES bytes receiving the unpacked message | |||
* @param[in] message Array of PARAM_K bytes storing the packed message | |||
*/ | |||
static void unpack_message(uint8_t *message_unpacked, const uint8_t *message) { | |||
for (size_t i = 0; i < (VEC_K_SIZE_BYTES - (PARAM_K % 8 != 0)); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
message_unpacked[j + 8 * i] = (message[i] >> j) & 0x01; | |||
} | |||
} | |||
for (int8_t j = 0; j < PARAM_K % 8; ++j) { | |||
message_unpacked[j + 8 * (VEC_K_SIZE_BYTES - 1)] = (message[VEC_K_SIZE_BYTES - 1] >> j) & 0x01; | |||
} | |||
} | |||
/** | |||
* @brief Encodes the message message to a codeword codeword using the generator polynomial bch_poly of the code | |||
* | |||
* @param[out] codeword Array of PARAM_N1 bytes receiving the codeword | |||
* @param[in] message Array of PARAM_K bytes storing the message to encode | |||
*/ | |||
static void lfsr_encode(uint8_t *codeword, const uint8_t *message) { | |||
uint8_t gate_value = 0; | |||
uint8_t bch_poly[PARAM_G] = PARAM_BCH_POLY; | |||
// Compute the Parity-check digits | |||
for (int16_t i = PARAM_K - 1; i >= 0; --i) { | |||
gate_value = message[i] ^ codeword[PARAM_N1 - PARAM_K - 1]; | |||
for (size_t j = PARAM_N1 - PARAM_K - 1; j; --j) { | |||
codeword[j] = codeword[j - 1] ^ (-gate_value & bch_poly[j]); | |||
} | |||
codeword[0] = gate_value; | |||
} | |||
// Add the message | |||
memcpy(codeword + PARAM_N1 - PARAM_K, message, PARAM_K); | |||
} | |||
/** | |||
* @brief Packs the codeword from an array codeword_unpacked where each byte stores a bit to a compact array codeword | |||
* | |||
* @param[out] codeword Array of VEC_N1_SIZE_BYTES bytes receiving the packed codeword | |||
* @param[in] codeword_unpacked Array of PARAM_N1 bytes storing the unpacked codeword | |||
*/ | |||
static void pack_codeword(uint8_t *codeword, const uint8_t *codeword_unpacked) { | |||
for (size_t i = 0; i < (VEC_N1_SIZE_BYTES - (PARAM_N1 % 8 != 0)); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
codeword[i] |= codeword_unpacked[j + 8 * i] << j; | |||
} | |||
} | |||
for (size_t j = 0; j < PARAM_N1 % 8; ++j) { | |||
codeword[VEC_N1_SIZE_BYTES - 1] |= codeword_unpacked[j + 8 * (VEC_N1_SIZE_BYTES - 1)] << j; | |||
} | |||
} | |||
/** | |||
* @brief Encodes a message message of PARAM_K bits to a BCH codeword codeword of PARAM_N1 bits | |||
* | |||
* Following @cite lin1983error (Chapter 4 - Cyclic Codes), | |||
* We perform a systematic encoding using a linear (PARAM_N1 - PARAM_K)-stage shift register | |||
* with feedback connections based on the generator polynomial bch_poly of the BCH code. | |||
* | |||
* @param[out] codeword Array of size VEC_N1_SIZE_BYTES receiving the encoded message | |||
* @param[in] message Array of size VEC_K_SIZE_BYTES storing the message | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_bch_code_encode(uint8_t *codeword, const uint8_t *message) { | |||
uint8_t message_unpacked[PARAM_K]; | |||
uint8_t codeword_unpacked[PARAM_N1] = {0}; | |||
unpack_message(message_unpacked, message); | |||
lfsr_encode(codeword_unpacked, message_unpacked); | |||
pack_codeword(codeword, codeword_unpacked); | |||
} | |||
/** | |||
* @brief Computes the error locator polynomial (ELP) sigma | |||
* | |||
* This is a constant time implementation of Berlekamp's simplified algorithm (see @cite joiner1995decoding). <br> | |||
* We use the letter p for rho which is initialized at -1/2. <br> | |||
* The array X_sigma_p represents the polynomial X^(2(mu-rho))*sigma_p(X). <br> | |||
* Instead of maintaining a list of sigmas, we update in place both sigma and X_sigma_p. <br> | |||
* sigma_copy serves as a temporary save of sigma in case X_sigma_p needs to be updated. <br> | |||
* We can properly correct only if the degree of sigma does not exceed PARAM_DELTA. | |||
* This means only the first PARAM_DELTA + 1 coefficients of sigma are of value | |||
* and we only need to save its first PARAM_DELTA - 1 coefficients. | |||
* | |||
* @returns the degree of the ELP sigma | |||
* @param[out] sigma Array of size (at least) PARAM_DELTA receiving the ELP | |||
* @param[in] syndromes Array of size (at least) 2*PARAM_DELTA storing the syndromes | |||
*/ | |||
static size_t compute_elp(uint16_t *sigma, const uint16_t *syndromes) { | |||
sigma[0] = 1; | |||
size_t deg_sigma = 0; | |||
size_t deg_sigma_p = 0; | |||
uint16_t sigma_copy[PARAM_DELTA - 1] = {0}; | |||
size_t deg_sigma_copy = 0; | |||
uint16_t X_sigma_p[PARAM_DELTA + 1] = {0, 1}; | |||
int32_t pp = -1; // 2*rho | |||
uint16_t d_p = 1; | |||
uint16_t d = syndromes[0]; | |||
for (size_t mu = 0; mu < PARAM_DELTA; ++mu) { | |||
// Save sigma in case we need it to update X_sigma_p | |||
memcpy(sigma_copy, sigma, 2 * (PARAM_DELTA - 1)); | |||
deg_sigma_copy = deg_sigma; | |||
uint16_t dd = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(d, PQCLEAN_HQC1281CCA2_LEAKTIME_gf_inverse(d_p)); // 0 if(d == 0) | |||
for (size_t i = 1; (i <= 2 * mu + 1) && (i <= PARAM_DELTA); ++i) { | |||
sigma[i] ^= PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(dd, X_sigma_p[i]); | |||
} | |||
size_t deg_X = 2 * mu - pp; // 2*(mu-rho) | |||
size_t deg_X_sigma_p = deg_X + deg_sigma_p; | |||
// mask1 = 0xffff if(d != 0) and 0 otherwise | |||
int16_t mask1 = -((uint16_t) - d >> 15); | |||
// mask2 = 0xffff if(deg_X_sigma_p > deg_sigma) and 0 otherwise | |||
int16_t mask2 = -((uint16_t) (deg_sigma - deg_X_sigma_p) >> 15); | |||
// mask12 = 0xffff if the deg_sigma increased and 0 otherwise | |||
int16_t mask12 = mask1 & mask2; | |||
deg_sigma = (mask12 & deg_X_sigma_p) ^ (~mask12 & deg_sigma); | |||
if (mu == PARAM_DELTA - 1) { | |||
break; | |||
} | |||
// Update pp, d_p and X_sigma_p if needed | |||
pp = (mask12 & (2 * mu)) ^ (~mask12 & pp); | |||
d_p = (mask12 & d) ^ (~mask12 & d_p); | |||
for (size_t i = PARAM_DELTA - 1; i; --i) { | |||
X_sigma_p[i + 1] = (mask12 & sigma_copy[i - 1]) ^ (~mask12 & X_sigma_p[i - 1]); | |||
} | |||
X_sigma_p[1] = 0; | |||
X_sigma_p[0] = 0; | |||
deg_sigma_p = (mask12 & deg_sigma_copy) ^ (~mask12 & deg_sigma_p); | |||
// Compute the next discrepancy | |||
d = syndromes[2 * mu + 2]; | |||
for (size_t i = 1; (i <= 2 * mu + 1) && (i <= PARAM_DELTA); ++i) { | |||
d ^= PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(sigma[i], syndromes[2 * mu + 2 - i]); | |||
} | |||
} | |||
return deg_sigma; | |||
} | |||
/** | |||
* @brief Retrieves the message message from the codeword codeword | |||
* | |||
* Since we performed a systematic encoding, the message is the last PARAM_K bits of the codeword. | |||
* | |||
* @param[out] message Array of size VEC_K_SIZE_BYTES receiving the message | |||
* @param[in] codeword Array of size VEC_N1_SIZE_BYTES storing the codeword | |||
*/ | |||
static void message_from_codeword(uint8_t *message, const uint8_t *codeword) { | |||
int32_t val = PARAM_N1 - PARAM_K; | |||
uint8_t mask1 = 0xff << val % 8; | |||
uint8_t mask2 = 0xff >> (8 - val % 8); | |||
size_t index = val / 8; | |||
for (size_t i = 0; i < VEC_K_SIZE_BYTES - 1; ++i) { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
uint8_t message2 = (codeword[++index] & mask2) << (8 - val % 8); | |||
message[i] = message1 | message2; | |||
} | |||
// Last byte (8-val % 8 is the number of bits given by message1) | |||
if ((PARAM_K % 8 == 0) || (8 - val % 8 < PARAM_K % 8)) { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
uint8_t message2 = (codeword[++index] & mask2) << (8 - val % 8); | |||
message[VEC_K_SIZE_BYTES - 1] = message1 | message2; | |||
} else { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
message[VEC_K_SIZE_BYTES - 1] = message1; | |||
} | |||
} | |||
/** | |||
* @brief Computes the 2^PARAM_DELTA syndromes from the received vector vector | |||
* | |||
* Syndromes are the sum of powers of alpha weighted by vector's coefficients. | |||
* To do so, we use the additive FFT transpose, which takes as input a family w of GF(2^PARAM_M) elements | |||
* and outputs the weighted power sums of these w. <br> | |||
* Therefore, this requires twisting and applying a permutation before feeding vector to the fft transpose. <br> | |||
* For more details see Berstein, Chou and Schawbe's explanations: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] syndromes Array of size 2^(PARAM_FFT_T) receiving the 2*PARAM_DELTA syndromes | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES storing the received word | |||
*/ | |||
static void compute_syndromes(uint16_t *syndromes, const uint8_t *vector) { | |||
uint16_t w[1 << PARAM_M]; | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(w, vector); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_fft_t(syndromes, w, 2 * PARAM_DELTA); | |||
} | |||
/** | |||
* @brief Computes the error polynomial error from the error locator polynomial sigma | |||
* | |||
* See function fft for more details. | |||
* | |||
* @param[out] err Array of VEC_N1_SIZE_BYTES elements receiving the error polynomial | |||
* @param[in] sigma Array of 2^PARAM_FFT elements storing the error locator polynomial | |||
*/ | |||
static void compute_roots(uint8_t *error, const uint16_t *sigma) { | |||
uint16_t w[1 << PARAM_M] = {0}; // w will receive the evaluation of sigma in all field elements | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_fft(w, sigma, PARAM_DELTA + 1); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_fft_retrieve_bch_error_poly(error, w); | |||
} | |||
/** | |||
* @brief Decodes the received word | |||
* | |||
* This function relies on four steps: | |||
* <ol> | |||
* <li> The first step, done by additive FFT transpose, is the computation of the 2*PARAM_DELTA syndromes. | |||
* <li> The second step is the computation of the error-locator polynomial sigma. | |||
* <li> The third step, done by additive FFT, is finding the error-locator numbers by calculating the roots of the polynomial sigma and takings their inverses. | |||
* <li> The fourth step is the correction of the errors in the received polynomial. | |||
* </ol> | |||
* For a more complete picture on BCH decoding, see Shu. Lin and Daniel J. Costello in Error Control Coding: Fundamentals and Applications @cite lin1983error | |||
* | |||
* @param[out] message Array of size VEC_K_SIZE_BYTES receiving the decoded message | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES storing the received word | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_bch_code_decode(uint8_t *message, uint8_t *vector) { | |||
uint16_t syndromes[1 << PARAM_FFT_T]; | |||
uint16_t sigma[1 << PARAM_FFT] = {0}; | |||
uint8_t error[(1 << PARAM_M) / 8] = {0}; | |||
// Calculate the 2*PARAM_DELTA syndromes | |||
compute_syndromes(syndromes, vector); | |||
// Compute the error locator polynomial sigma | |||
// Sigma's degree is at most PARAM_DELTA but the FFT requires the extra room | |||
compute_elp(sigma, syndromes); | |||
// Compute the error polynomial error | |||
compute_roots(error, sigma); | |||
// Add the error polynomial to the received polynomial | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_add(vector, vector, error, VEC_N1_SIZE_BYTES); | |||
// Retrieve the message from the decoded codeword | |||
message_from_codeword(message, vector); | |||
} |
@@ -1,16 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1281CCA2_LEAKTIME_BCH_H | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_BCH_H | |||
/** | |||
* @file bch.h | |||
* Header file of bch.c | |||
*/ | |||
#include "parameters.h" | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_bch_code_encode(uint8_t *codeword, const uint8_t *message); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_bch_code_decode(uint8_t *message, uint8_t *vector); | |||
#endif |
@@ -1,628 +0,0 @@ | |||
/** | |||
* @file fft.c | |||
* Implementation of the additive FFT and its transpose. | |||
* This implementation is based on the paper from Gao and Mateer: <br> | |||
* Shuhong Gao and Todd Mateer, Additive Fast Fourier Transforms over Finite Fields, | |||
* IEEE Transactions on Information Theory 56 (2010), 6265--6272. | |||
* http://www.math.clemson.edu/~sgao/papers/GM10.pdf <br> | |||
* and includes improvements proposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
*/ | |||
#include "fft.h" | |||
#include "gf.h" | |||
#include "parameters.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
static void compute_fft_betas(uint16_t *betas); | |||
static void compute_subset_sums(uint16_t *subset_sums, const uint16_t *set, size_t set_size); | |||
static void radix_t(uint16_t *f, const uint16_t *f0, const uint16_t *f1, uint32_t m_f); | |||
static void fft_t_rec(uint16_t *f, const uint16_t *w, size_t f_coeffs, uint8_t m, uint32_t m_f, const uint16_t *betas); | |||
static void radix(uint16_t *f0, uint16_t *f1, const uint16_t *f, uint32_t m_f); | |||
static void fft_rec(uint16_t *w, uint16_t *f, size_t f_coeffs, uint8_t m, uint32_t m_f, const uint16_t *betas); | |||
/** | |||
* @brief Computes the basis of betas (omitting 1) used in the additive FFT and its transpose | |||
* | |||
* @param[out] betas Array of size PARAM_M-1 | |||
*/ | |||
static void compute_fft_betas(uint16_t *betas) { | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
betas[i] = 1 << (PARAM_M - 1 - i); | |||
} | |||
} | |||
/** | |||
* @brief Computes the subset sums of the given set | |||
* | |||
* The array subset_sums is such that its ith element is | |||
* the subset sum of the set elements given by the binary form of i. | |||
* | |||
* @param[out] subset_sums Array of size 2^set_size receiving the subset sums | |||
* @param[in] set Array of set_size elements | |||
* @param[in] set_size Size of the array set | |||
*/ | |||
static void compute_subset_sums(uint16_t *subset_sums, const uint16_t *set, size_t set_size) { | |||
subset_sums[0] = 0; | |||
for (size_t i = 0; i < set_size; ++i) { | |||
for (size_t j = 0; j < (((size_t)1) << i); ++j) { | |||
subset_sums[(((size_t)1) << i) + j] = set[i] ^ subset_sums[j]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Transpose of the linear radix conversion | |||
* | |||
* This is a direct transposition of the radix function | |||
* implemented following the process of transposing a linear function as exposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f Array of size a power of 2 | |||
* @param[in] f0 Array half the size of f | |||
* @param[in] f1 Array half the size of f | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the number of coefficients of f | |||
*/ | |||
static void radix_t(uint16_t *f, const uint16_t *f0, const uint16_t *f1, uint32_t m_f) { | |||
switch (m_f) { | |||
case 4: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
f[4] = f[2] ^ f0[2]; | |||
f[5] = f[3] ^ f1[2]; | |||
f[6] = f[4] ^ f0[3] ^ f1[2]; | |||
f[7] = f[3] ^ f0[3] ^ f1[3]; | |||
f[8] = f[4] ^ f0[4]; | |||
f[9] = f[5] ^ f1[4]; | |||
f[10] = f[6] ^ f0[5] ^ f1[4]; | |||
f[11] = f[7] ^ f0[5] ^ f1[4] ^ f1[5]; | |||
f[12] = f[8] ^ f0[5] ^ f0[6] ^ f1[4]; | |||
f[13] = f[7] ^ f[9] ^ f[11] ^ f1[6]; | |||
f[14] = f[6] ^ f0[6] ^ f0[7] ^ f1[6]; | |||
f[15] = f[7] ^ f0[7] ^ f1[7]; | |||
return; | |||
case 3: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
f[4] = f[2] ^ f0[2]; | |||
f[5] = f[3] ^ f1[2]; | |||
f[6] = f[4] ^ f0[3] ^ f1[2]; | |||
f[7] = f[3] ^ f0[3] ^ f1[3]; | |||
return; | |||
case 2: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
return; | |||
case 1: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
return; | |||
default: | |||
; | |||
size_t n = ((size_t)1) << (m_f - 2); | |||
uint16_t Q0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t Q1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t Q[1 << 2 * (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R[1 << 2 * (PARAM_FFT_T - 2)] = {0}; | |||
memcpy(Q0, f0 + n, 2 * n); | |||
memcpy(Q1, f1 + n, 2 * n); | |||
memcpy(R0, f0, 2 * n); | |||
memcpy(R1, f1, 2 * n); | |||
radix_t (Q, Q0, Q1, m_f - 1); | |||
radix_t (R, R0, R1, m_f - 1); | |||
memcpy(f, R, 4 * n); | |||
memcpy(f + 2 * n, R + n, 2 * n); | |||
memcpy(f + 3 * n, Q + n, 2 * n); | |||
for (size_t i = 0; i < n; ++i) { | |||
f[2 * n + i] ^= Q[i]; | |||
f[3 * n + i] ^= f[2 * n + i]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Recursively computes syndromes of family w | |||
* | |||
* This function is a subroutine of the function fft_t | |||
* | |||
* @param[out] f Array receiving the syndromes | |||
* @param[in] w Array storing the family | |||
* @param[in] f_coeffs Length of syndromes vector | |||
* @param[in] m 2^m is the smallest power of 2 greater or equal to the length of family w | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the length of f | |||
* @param[in] betas FFT constants | |||
*/ | |||
static void fft_t_rec(uint16_t *f, const uint16_t *w, size_t f_coeffs, | |||
uint8_t m, uint32_t m_f, const uint16_t *betas) { | |||
size_t k = ((size_t)1) << (m - 1); | |||
uint16_t gammas[PARAM_M - 2] = {0}; | |||
uint16_t deltas[PARAM_M - 2] = {0}; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
uint16_t u[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t f0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)] = {0}; | |||
// Step 1 | |||
if (m_f == 1) { | |||
for (size_t i = 0; i < (((size_t)1) << m); ++i) { | |||
f[0] ^= w[i]; | |||
} | |||
for (size_t j = 0; j < m; ++j) { | |||
for (size_t ki = 0; ki < (((size_t)1) << j); ++ki) { | |||
size_t index = (((size_t)1) << j) + ki; | |||
betas_sums[index] = betas_sums[ki] ^ betas[j]; | |||
f[1] ^= PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(betas_sums[index], w[index]); | |||
} | |||
} | |||
return; | |||
} | |||
// Compute gammas and deltas | |||
for (uint8_t i = 0; i < m - 1; ++i) { | |||
gammas[i] = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(betas[i], PQCLEAN_HQC1281CCA2_LEAKTIME_gf_inverse(betas[m - 1])); | |||
deltas[i] = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_square(gammas[i]) ^ gammas[i]; | |||
} | |||
// Compute gammas subset sums | |||
compute_subset_sums(gammas_sums, gammas, m - 1); | |||
/* Step 6: Compute u and v from w (aka w) | |||
* w[i] = u[i] + G[i].v[i] | |||
* w[k+i] = w[i] + v[i] = u[i] + (G[i]+1).v[i] | |||
* Transpose: | |||
* u[i] = w[i] + w[k+i] | |||
* v[i] = G[i].w[i] + (G[i]+1).w[k+i] = G[i].u[i] + w[k+i] */ | |||
if (f_coeffs <= 3) { // 3-coefficient polynomial f case | |||
// Step 5: Compute f0 from u and f1 from v | |||
f1[1] = 0; | |||
u[0] = w[0] ^ w[k]; | |||
f1[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
f1[0] ^= PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(gammas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
} else { | |||
uint16_t v[1 << (PARAM_M - 2)] = {0}; | |||
u[0] = w[0] ^ w[k]; | |||
v[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
v[i] = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(gammas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
// Step 5: Compute f0 from u and f1 from v | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
fft_t_rec(f1, v, f_coeffs / 2, m - 1, m_f - 1, deltas); | |||
} | |||
// Step 3: Compute g from g0 and g1 | |||
radix_t(f, f0, f1, m_f); | |||
// Step 2: compute f from g | |||
if (betas[m - 1] != 1) { | |||
uint16_t beta_m_pow = 1; | |||
for (size_t i = 1; i < (((size_t)1) << m_f); ++i) { | |||
beta_m_pow = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(beta_m_pow, betas[m - 1]); | |||
f[i] = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(beta_m_pow, f[i]); | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Computes the syndromes f of the family w | |||
* | |||
* Since the syndromes linear map is the transpose of multipoint evaluation, | |||
* it uses exactly the same constants, either hardcoded or precomputed by compute_fft_lut(...). <br> | |||
* This follows directives from Bernstein, Chou and Schwabe given here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f Array of size 2*(PARAM_FFT_T) elements receiving the syndromes | |||
* @param[in] w Array of PARAM_GF_MUL_ORDER+1 elements | |||
* @param[in] f_coeffs Length of syndromes vector f | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_fft_t(uint16_t *f, const uint16_t *w, size_t f_coeffs) { | |||
// Transposed from Gao and Mateer algorithm | |||
uint16_t betas[PARAM_M - 1]; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
uint16_t u[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t deltas[PARAM_M - 1]; | |||
uint16_t f0[1 << (PARAM_FFT_T - 1)]; | |||
uint16_t f1[1 << (PARAM_FFT_T - 1)]; | |||
compute_fft_betas(betas); | |||
compute_subset_sums(betas_sums, betas, PARAM_M - 1); | |||
/* Step 6: Compute u and v from w (aka w) | |||
* | |||
* We had: | |||
* w[i] = u[i] + G[i].v[i] | |||
* w[k+i] = w[i] + v[i] = u[i] + (G[i]+1).v[i] | |||
* Transpose: | |||
* u[i] = w[i] + w[k+i] | |||
* v[i] = G[i].w[i] + (G[i]+1).w[k+i] = G[i].u[i] + w[k+i] */ | |||
u[0] = w[0] ^ w[k]; | |||
v[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
v[i] = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(betas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
// Compute deltas | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
deltas[i] = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_square(betas[i]) ^ betas[i]; | |||
} | |||
// Step 5: Compute f0 from u and f1 from v | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, PARAM_M - 1, PARAM_FFT_T - 1, deltas); | |||
fft_t_rec(f1, v, f_coeffs / 2, PARAM_M - 1, PARAM_FFT_T - 1, deltas); | |||
// Step 3: Compute g from g0 and g1 | |||
radix_t(f, f0, f1, PARAM_FFT_T); | |||
// Step 2: beta_m = 1 so f = g | |||
} | |||
/** | |||
* @brief Computes the radix conversion of a polynomial f in GF(2^m)[x] | |||
* | |||
* Computes f0 and f1 such that f(x) = f0(x^2-x) + x.f1(x^2-x) | |||
* as proposed by Bernstein, Chou and Schwabe: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f0 Array half the size of f | |||
* @param[out] f1 Array half the size of f | |||
* @param[in] f Array of size a power of 2 | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the number of coefficients of f | |||
*/ | |||
static void radix(uint16_t *f0, uint16_t *f1, const uint16_t *f, uint32_t m_f) { | |||
switch (m_f) { | |||
case 4: | |||
f0[4] = f[8] ^ f[12]; | |||
f0[6] = f[12] ^ f[14]; | |||
f0[7] = f[14] ^ f[15]; | |||
f1[5] = f[11] ^ f[13]; | |||
f1[6] = f[13] ^ f[14]; | |||
f1[7] = f[15]; | |||
f0[5] = f[10] ^ f[12] ^ f1[5]; | |||
f1[4] = f[9] ^ f[13] ^ f0[5]; | |||
f0[0] = f[0]; | |||
f1[3] = f[7] ^ f[11] ^ f[15]; | |||
f0[3] = f[6] ^ f[10] ^ f[14] ^ f1[3]; | |||
f0[2] = f[4] ^ f0[4] ^ f0[3] ^ f1[3]; | |||
f1[1] = f[3] ^ f[5] ^ f[9] ^ f[13] ^ f1[3]; | |||
f1[2] = f[3] ^ f1[1] ^ f0[3]; | |||
f0[1] = f[2] ^ f0[2] ^ f1[1]; | |||
f1[0] = f[1] ^ f0[1]; | |||
return; | |||
case 3: | |||
f0[0] = f[0]; | |||
f0[2] = f[4] ^ f[6]; | |||
f0[3] = f[6] ^ f[7]; | |||
f1[1] = f[3] ^ f[5] ^ f[7]; | |||
f1[2] = f[5] ^ f[6]; | |||
f1[3] = f[7]; | |||
f0[1] = f[2] ^ f0[2] ^ f1[1]; | |||
f1[0] = f[1] ^ f0[1]; | |||
return; | |||
case 2: | |||
f0[0] = f[0]; | |||
f0[1] = f[2] ^ f[3]; | |||
f1[0] = f[1] ^ f0[1]; | |||
f1[1] = f[3]; | |||
return; | |||
case 1: | |||
f0[0] = f[0]; | |||
f1[0] = f[1]; | |||
return; | |||
default: | |||
; | |||
size_t n = ((size_t)1) << (m_f - 2); | |||
uint16_t Q[2 * (1 << (PARAM_FFT - 2))]; | |||
uint16_t R[2 * (1 << (PARAM_FFT - 2))]; | |||
uint16_t Q0[1 << (PARAM_FFT - 2)]; | |||
uint16_t Q1[1 << (PARAM_FFT - 2)]; | |||
uint16_t R0[1 << (PARAM_FFT - 2)]; | |||
uint16_t R1[1 << (PARAM_FFT - 2)]; | |||
memcpy(Q, f + 3 * n, 2 * n); | |||
memcpy(Q + n, f + 3 * n, 2 * n); | |||
memcpy(R, f, 4 * n); | |||
for (size_t i = 0; i < n; ++i) { | |||
Q[i] ^= f[2 * n + i]; | |||
R[n + i] ^= Q[i]; | |||
} | |||
radix(Q0, Q1, Q, m_f - 1); | |||
radix(R0, R1, R, m_f - 1); | |||
memcpy(f0, R0, 2 * n); | |||
memcpy(f0 + n, Q0, 2 * n); | |||
memcpy(f1, R1, 2 * n); | |||
memcpy(f1 + n, Q1, 2 * n); | |||
} | |||
} | |||
/** | |||
* @brief Evaluates f at all subset sums of a given set | |||
* | |||
* This function is a subroutine of the function fft. | |||
* | |||
* @param[out] w Array | |||
* @param[in] f Array | |||
* @param[in] f_coeffs Number of coefficients of f | |||
* @param[in] m Number of betas | |||
* @param[in] m_f Number of coefficients of f (one more than its degree) | |||
* @param[in] betas FFT constants | |||
*/ | |||
static void fft_rec(uint16_t *w, uint16_t *f, size_t f_coeffs, | |||
uint8_t m, uint32_t m_f, const uint16_t *betas) { | |||
uint16_t f0[1 << (PARAM_FFT - 2)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT - 2)] = {0}; | |||
uint16_t gammas[PARAM_M - 2] = {0}; | |||
uint16_t deltas[PARAM_M - 2] = {0}; | |||
size_t k = ((size_t)1) << (m - 1); | |||
uint16_t gammas_sums[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t u[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 2)] = {0}; | |||
// Step 1 | |||
if (m_f == 1) { | |||
uint16_t tmp[PARAM_M - (PARAM_FFT - 1)]; | |||
for (size_t i = 0; i < m; ++i) { | |||
tmp[i] = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(betas[i], f[1]); | |||
} | |||
w[0] = f[0]; | |||
for (size_t j = 0; j < m; ++j) { | |||
for (size_t ki = 0; ki < (((size_t)1) << j); ++ki) { | |||
w[(((size_t)1) << j) + ki] = w[ki] ^ tmp[j]; | |||
} | |||
} | |||
return; | |||
} | |||
// Step 2: compute g | |||
if (betas[m - 1] != 1) { | |||
uint16_t beta_m_pow = 1; | |||
for (size_t i = 1; i < (((size_t)1) << m_f); ++i) { | |||
beta_m_pow = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(beta_m_pow, betas[m - 1]); | |||
f[i] = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(beta_m_pow, f[i]); | |||
} | |||
} | |||
// Step 3 | |||
radix(f0, f1, f, m_f); | |||
// Step 4: compute gammas and deltas | |||
for (uint8_t i = 0; i < m - 1; ++i) { | |||
gammas[i] = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(betas[i], PQCLEAN_HQC1281CCA2_LEAKTIME_gf_inverse(betas[m - 1])); | |||
deltas[i] = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_square(gammas[i]) ^ gammas[i]; | |||
} | |||
// Compute gammas sums | |||
compute_subset_sums(gammas_sums, gammas, m - 1); | |||
// Step 5 | |||
fft_rec(u, f0, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
if (f_coeffs <= 3) { // 3-coefficient polynomial f case: f1 is constant | |||
w[0] = u[0]; | |||
w[k] = u[0] ^ f1[0]; | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(gammas_sums[i], f1[0]); | |||
w[k + i] = w[i] ^ f1[0]; | |||
} | |||
} else { | |||
fft_rec(v, f1, f_coeffs / 2, m - 1, m_f - 1, deltas); | |||
// Step 6 | |||
memcpy(w + k, v, 2 * k); | |||
w[0] = u[0]; | |||
w[k] ^= u[0]; | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(gammas_sums[i], v[i]); | |||
w[k + i] ^= w[i]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Evaluates f on all fields elements using an additive FFT algorithm | |||
* | |||
* f_coeffs is the number of coefficients of f (one less than its degree). <br> | |||
* The FFT proceeds recursively to evaluate f at all subset sums of a basis B. <br> | |||
* This implementation is based on the paper from Gao and Mateer: <br> | |||
* Shuhong Gao and Todd Mateer, Additive Fast Fourier Transforms over Finite Fields, | |||
* IEEE Transactions on Information Theory 56 (2010), 6265--6272. | |||
* http://www.math.clemson.edu/~sgao/papers/GM10.pdf <br> | |||
* and includes improvements proposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf <br> | |||
* Constants betas, gammas and deltas involved in the algorithm are either hardcoded or precomputed | |||
* by the subroutine compute_fft_lut(...). <br> | |||
* Note that on this first call (as opposed to the recursive calls to fft_rec), gammas are equal to betas, | |||
* meaning the first gammas subset sums are actually the subset sums of betas (except 1). <br> | |||
* Also note that f is altered during computation (twisted at each level). | |||
* | |||
* @param[out] w Array | |||
* @param[in] f Array of 2^PARAM_FFT elements | |||
* @param[in] f_coeffs Number coefficients of f (i.e. deg(f)+1) | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_fft(uint16_t *w, const uint16_t *f, size_t f_coeffs) { | |||
uint16_t betas[PARAM_M - 1] = {0}; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t f0[1 << (PARAM_FFT - 1)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT - 1)] = {0}; | |||
uint16_t deltas[PARAM_M - 1]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
uint16_t u[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 1)] = {0}; | |||
// Follows Gao and Mateer algorithm | |||
compute_fft_betas(betas); | |||
// Step 1: PARAM_FFT > 1, nothing to do | |||
// Compute gammas sums | |||
compute_subset_sums(betas_sums, betas, PARAM_M - 1); | |||
// Step 2: beta_m = 1, nothing to do | |||
// Step 3 | |||
radix(f0, f1, f, PARAM_FFT); | |||
// Step 4: Compute deltas | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
deltas[i] = PQCLEAN_HQC1281CCA2_LEAKTIME_gf_square(betas[i]) ^ betas[i]; | |||
} | |||
// Step 5 | |||
fft_rec(u, f0, (f_coeffs + 1) / 2, PARAM_M - 1, PARAM_FFT - 1, deltas); | |||
fft_rec(v, f1, f_coeffs / 2, PARAM_M - 1, PARAM_FFT - 1, deltas); | |||
// Step 6, 7 and error polynomial computation | |||
memcpy(w + k, v, 2 * k); | |||
// Check if 0 is root | |||
w[0] = u[0]; | |||
// Check if 1 is root | |||
w[k] ^= u[0]; | |||
// Find other roots | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(betas_sums[i], v[i]); | |||
w[k + i] ^= w[i]; | |||
} | |||
} | |||
/** | |||
* @brief Arranges the received word vector in a form w such that applying the additive FFT transpose to w yields the BCH syndromes of the received word vector. | |||
* | |||
* Since the received word vector gives coefficients of the primitive element alpha, we twist accordingly. <br> | |||
* Furthermore, the additive FFT transpose needs elements indexed by their decomposition on the chosen basis, | |||
* so we apply the adequate permutation. | |||
* | |||
* @param[out] w Array of size 2^PARAM_M | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(uint16_t *w, const uint8_t *vector) { | |||
uint16_t r[1 << PARAM_M]; | |||
uint16_t gammas[PARAM_M - 1]; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
// Unpack the received word vector into array r | |||
size_t i; | |||
for (i = 0; i < VEC_N1_SIZE_BYTES - (PARAM_N1 % 8 != 0); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
r[8 * i + j] = (vector[i] >> j) & 1; | |||
} | |||
} | |||
// Last byte | |||
for (size_t j = 0; j < PARAM_N1 % 8; ++j) { | |||
r[8 * i + j] = (vector[i] >> j) & 1; | |||
} | |||
// Complete r with zeros | |||
memset(r + PARAM_N1, 0, 2 * ((1 << PARAM_M) - PARAM_N1)); | |||
compute_fft_betas(gammas); | |||
compute_subset_sums(gammas_sums, gammas, PARAM_M - 1); | |||
// Twist and permute r adequately to obtain w | |||
w[0] = 0; | |||
w[k] = -r[0] & 1; | |||
for (i = 1; i < k; ++i) { | |||
w[i] = -r[PQCLEAN_HQC1281CCA2_LEAKTIME_gf_log(gammas_sums[i])] & gammas_sums[i]; | |||
w[k + i] = -r[PQCLEAN_HQC1281CCA2_LEAKTIME_gf_log(gammas_sums[i] ^ 1)] & (gammas_sums[i] ^ 1); | |||
} | |||
} | |||
/** | |||
* @brief Retrieves the error polynomial error from the evaluations w of the ELP (Error Locator Polynomial) on all field elements. | |||
* | |||
* @param[out] error Array of size VEC_N1_SIZE_BYTES | |||
* @param[in] w Array of size 2^PARAM_M | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_fft_retrieve_bch_error_poly(uint8_t *error, const uint16_t *w) { | |||
uint16_t gammas[PARAM_M - 1]; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
size_t index = PARAM_GF_MUL_ORDER; | |||
compute_fft_betas(gammas); | |||
compute_subset_sums(gammas_sums, gammas, PARAM_M - 1); | |||
error[0] ^= 1 ^ ((uint16_t) - w[0] >> 15); | |||
uint8_t bit = 1 ^ ((uint16_t) - w[k] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
for (size_t i = 1; i < k; ++i) { | |||
index = PARAM_GF_MUL_ORDER - PQCLEAN_HQC1281CCA2_LEAKTIME_gf_log(gammas_sums[i]); | |||
bit = 1 ^ ((uint16_t) - w[i] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
index = PARAM_GF_MUL_ORDER - PQCLEAN_HQC1281CCA2_LEAKTIME_gf_log(gammas_sums[i] ^ 1); | |||
bit = 1 ^ ((uint16_t) - w[k + i] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
} | |||
} |
@@ -1,18 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1281CCA2_LEAKTIME_FFT_H | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_FFT_H | |||
/** | |||
* @file fft.h | |||
* Header file of fft.c | |||
*/ | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_fft_t(uint16_t *f, const uint16_t *w, size_t f_coeffs); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(uint16_t *w, const uint8_t *vector); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_fft(uint16_t *w, const uint16_t *f, size_t f_coeffs); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_fft_retrieve_bch_error_poly(uint8_t *error, const uint16_t *w); | |||
#endif |
@@ -1,18 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1281CCA2_LEAKTIME_GF_H | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_GF_H | |||
/** | |||
* @file gf.h | |||
* Header file of gf.c | |||
*/ | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
uint16_t PQCLEAN_HQC1281CCA2_LEAKTIME_gf_log(uint16_t elt); | |||
uint16_t PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mul(uint16_t a, uint16_t b); | |||
uint16_t PQCLEAN_HQC1281CCA2_LEAKTIME_gf_square(uint16_t a); | |||
uint16_t PQCLEAN_HQC1281CCA2_LEAKTIME_gf_inverse(uint16_t a); | |||
uint16_t PQCLEAN_HQC1281CCA2_LEAKTIME_gf_mod(uint16_t i); | |||
#endif |
@@ -1,123 +0,0 @@ | |||
/** | |||
* \file gf2x.c | |||
* \brief Implementation of multiplication of two polynomials | |||
*/ | |||
#include "gf2x.h" | |||
#include "parameters.h" | |||
#include "util.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
#define WORD_TYPE uint64_t | |||
#define WORD_TYPE_BITS (sizeof(WORD_TYPE) * 8) | |||
#define UTILS_VECTOR_ARRAY_SIZE CEIL_DIVIDE(PARAM_N, WORD_TYPE_BITS) | |||
static int vect_mul_precompute_rows(WORD_TYPE *o, const WORD_TYPE *v); | |||
/** | |||
* @brief A subroutine used in the function sparse_dense_mul() | |||
* | |||
* @param[out] o Pointer to an array | |||
* @param[in] v Pointer to an array | |||
* @return 0 if precomputation is successful, -1 otherwise | |||
*/ | |||
static int vect_mul_precompute_rows(WORD_TYPE *o, const WORD_TYPE *v) { | |||
int8_t var; | |||
for (size_t i = 0; i < PARAM_N; ++i) { | |||
var = 0; | |||
// All the bits that we need are in the same block | |||
if (((i % WORD_TYPE_BITS) == 0) && (i != PARAM_N - (PARAM_N % WORD_TYPE_BITS))) { | |||
var = 1; | |||
} | |||
// Cases where the bits are in before the last block, the last block and the first block | |||
if (i > PARAM_N - WORD_TYPE_BITS) { | |||
if (i >= PARAM_N - (PARAM_N % WORD_TYPE_BITS)) { | |||
var = 2; | |||
} else { | |||
var = 3; | |||
} | |||
} | |||
switch (var) { | |||
case 0: | |||
// Take bits in the last block and the first one | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[(i / WORD_TYPE_BITS) + 1] << (WORD_TYPE_BITS - (i % WORD_TYPE_BITS)); | |||
break; | |||
case 1: | |||
o[i] = v[i / WORD_TYPE_BITS]; | |||
break; | |||
case 2: | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[0] << ((PARAM_N - i) % WORD_TYPE_BITS); | |||
break; | |||
case 3: | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[(i / WORD_TYPE_BITS) + 1] << (WORD_TYPE_BITS - (i % WORD_TYPE_BITS)); | |||
o[i] += v[0] << ((WORD_TYPE_BITS - i + (PARAM_N % WORD_TYPE_BITS)) % WORD_TYPE_BITS); | |||
break; | |||
default: | |||
return -1; | |||
} | |||
} | |||
return 0; | |||
} | |||
/** | |||
* @brief Multiplies two vectors | |||
* | |||
* This function multiplies two vectors: a sparse vector of Hamming weight equal to <b>weight</b> and a dense (random) vector. | |||
* The vector <b>a1</b> is the sparse vector and <b>a2</b> is the dense vector. | |||
* We notice that the idea is explained using vector of 32 bits elements instead of 64 (the algorithm works in booth cases). | |||
* | |||
* @param[out] o Pointer to a vector that is the result of the multiplication | |||
* @param[in] a1 Pointer to the sparse vector stored by position | |||
* @param[in] a2 Pointer to the dense vector | |||
* @param[in] weight Integer that is the weight of the sparse vector | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_mul(uint8_t *o, const uint32_t *a1, const uint8_t *a2, uint16_t weight) { | |||
WORD_TYPE v1[UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
WORD_TYPE res[UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
WORD_TYPE precomputation_array [PARAM_N] = {0}; | |||
WORD_TYPE row [UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
uint32_t index; | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_load8_arr(v1, UTILS_VECTOR_ARRAY_SIZE, a2, VEC_N_SIZE_BYTES); | |||
vect_mul_precompute_rows(precomputation_array, v1); | |||
for (size_t i = 0; i < weight; ++i) { | |||
int32_t k = UTILS_VECTOR_ARRAY_SIZE; | |||
for (size_t j = 0; j < UTILS_VECTOR_ARRAY_SIZE - 1; ++j) { | |||
index = WORD_TYPE_BITS * (uint32_t)j - a1[i]; | |||
if (index > PARAM_N) { | |||
index += PARAM_N; | |||
} | |||
row[j] = precomputation_array[index]; | |||
} | |||
index = WORD_TYPE_BITS * (UTILS_VECTOR_ARRAY_SIZE - 1) - a1[i]; | |||
row[UTILS_VECTOR_ARRAY_SIZE - 1] = precomputation_array[(index < PARAM_N ? index : index + PARAM_N)] & BITMASK(PARAM_N, WORD_TYPE_BITS); | |||
while (k--) { | |||
res[k] ^= row[k]; | |||
} | |||
} | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_store8_arr(o, VEC_N_SIZE_BYTES, res, UTILS_VECTOR_ARRAY_SIZE); | |||
} |
@@ -1,13 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1281CCA2_LEAKTIME_GF2X_H | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_GF2X_H | |||
/** | |||
* @file gf2x.h | |||
* @brief Header file for gf2x.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_mul(uint8_t *o, const uint32_t *a1, const uint8_t *a2, uint16_t weight); | |||
#endif |
@@ -1,135 +0,0 @@ | |||
/** | |||
* @file hqc.c | |||
* @brief Implementation of hqc.h | |||
*/ | |||
#include "gf2x.h" | |||
#include "hqc.h" | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "randombytes.h" | |||
#include "tensor.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
/** | |||
* @brief Keygen of the HQC_PKE IND_CPA scheme | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the <b>seed</b> used to generate the vector <b>h</b>. | |||
* | |||
* The secret key is composed of the <b>seed</b> used to generate vectors <b>x</b> and <b>y</b>. | |||
* As a technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[out] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_pke_keygen(uint8_t *pk, uint8_t *sk) { | |||
AES_XOF_struct sk_seedexpander; | |||
AES_XOF_struct pk_seedexpander; | |||
uint8_t sk_seed[SEED_BYTES] = {0}; | |||
uint8_t pk_seed[SEED_BYTES] = {0}; | |||
uint8_t x[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t y[PARAM_OMEGA] = {0}; | |||
uint8_t h[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t s[VEC_N_SIZE_BYTES] = {0}; | |||
// Create seed_expanders for public key and secret key | |||
randombytes(sk_seed, SEED_BYTES); | |||
seedexpander_init(&sk_seedexpander, sk_seed, sk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
randombytes(pk_seed, SEED_BYTES); | |||
seedexpander_init(&pk_seedexpander, pk_seed, pk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
// Compute secret key | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_fixed_weight(&sk_seedexpander, x, PARAM_OMEGA); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&sk_seedexpander, y, PARAM_OMEGA); | |||
// Compute public key | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random(&pk_seedexpander, h); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_mul(s, y, h, PARAM_OMEGA); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_add(s, x, s, VEC_N_SIZE_BYTES); | |||
// Parse keys to string | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_public_key_to_string(pk, pk_seed, s); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_secret_key_to_string(sk, sk_seed, pk); | |||
} | |||
/** | |||
* @brief Encryption of the HQC_PKE IND_CPA scheme | |||
* | |||
* The cihertext is composed of vectors <b>u</b> and <b>v</b>. | |||
* | |||
* @param[out] u Vector u (first part of the ciphertext) | |||
* @param[out] v Vector v (second part of the ciphertext) | |||
* @param[in] m Vector representing the message to encrypt | |||
* @param[in] theta Seed used to derive randomness required for encryption | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_pke_encrypt(uint8_t *u, uint8_t *v, const uint8_t *m, const uint8_t *theta, const uint8_t *pk) { | |||
AES_XOF_struct seedexpander; | |||
uint8_t h[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t s[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t r1[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t r2[PARAM_OMEGA_R] = {0}; | |||
uint8_t e[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp1[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp2[VEC_N_SIZE_BYTES] = {0}; | |||
// Create seed_expander from theta | |||
seedexpander_init(&seedexpander, theta, theta + 32, SEEDEXPANDER_MAX_LENGTH); | |||
// Retrieve h and s from public key | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_public_key_from_string(h, s, pk); | |||
// Generate r1, r2 and e | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_fixed_weight(&seedexpander, r1, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&seedexpander, r2, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_fixed_weight(&seedexpander, e, PARAM_OMEGA_E); | |||
// Compute u = r1 + r2.h | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_mul(u, r2, h, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_add(u, r1, u, VEC_N_SIZE_BYTES); | |||
// Compute v = m.G by encoding the message | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_tensor_code_encode(v, m); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_resize(tmp1, PARAM_N, v, PARAM_N1N2); | |||
// Compute v = m.G + s.r2 + e | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_mul(tmp2, r2, s, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_add(tmp2, e, tmp2, VEC_N_SIZE_BYTES); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_add(tmp2, tmp1, tmp2, VEC_N_SIZE_BYTES); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_resize(v, PARAM_N1N2, tmp2, PARAM_N); | |||
} | |||
/** | |||
* @brief Decryption of the HQC_PKE IND_CPA scheme | |||
* | |||
* @param[out] m Vector representing the decrypted message | |||
* @param[in] u Vector u (first part of the ciphertext) | |||
* @param[in] v Vector v (second part of the ciphertext) | |||
* @param[in] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_pke_decrypt(uint8_t *m, const uint8_t *u, const uint8_t *v, const uint8_t *sk) { | |||
uint8_t x[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t y[PARAM_OMEGA] = {0}; | |||
uint8_t pk[PUBLIC_KEY_BYTES] = {0}; | |||
uint8_t tmp1[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp2[VEC_N_SIZE_BYTES] = {0}; | |||
// Retrieve x, y, pk from secret key | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_secret_key_from_string(x, y, pk, sk); | |||
// Compute v - u.y | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_resize(tmp1, PARAM_N, v, PARAM_N1N2); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_mul(tmp2, y, u, PARAM_OMEGA); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_add(tmp2, tmp1, tmp2, VEC_N_SIZE_BYTES); | |||
// Compute m by decoding v - u.y | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_tensor_code_decode(m, tmp2); | |||
} |
@@ -1,15 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1281CCA2_LEAKTIME_HQC_H | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_HQC_H | |||
/** | |||
* @file hqc.h | |||
* @brief Functions of the HQC_PKE IND_CPA scheme | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_pke_keygen(uint8_t *pk, uint8_t *sk); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_pke_encrypt(uint8_t *u, uint8_t *v, const uint8_t *m, const uint8_t *theta, const uint8_t *pk); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_pke_decrypt(uint8_t *m, const uint8_t *u, const uint8_t *v, const uint8_t *sk); | |||
#endif |
@@ -1,154 +0,0 @@ | |||
/** | |||
* @file kem.c | |||
* @brief Implementation of api.h | |||
*/ | |||
#include "api.h" | |||
#include "hqc.h" | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "sha2.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
/** | |||
* @brief Keygen of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b>. | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As a technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[out] sk String containing the secret key | |||
* @returns 0 if keygen is successful | |||
*/ | |||
int PQCLEAN_HQC1281CCA2_LEAKTIME_crypto_kem_keypair(uint8_t *pk, uint8_t *sk) { | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_pke_keygen(pk, sk); | |||
return 0; | |||
} | |||
/** | |||
* @brief Encapsulation of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* @param[out] ct String containing the ciphertext | |||
* @param[out] ss String containing the shared secret | |||
* @param[in] pk String containing the public key | |||
* @returns 0 if encapsulation is successful | |||
*/ | |||
int PQCLEAN_HQC1281CCA2_LEAKTIME_crypto_kem_enc(uint8_t *ct, uint8_t *ss, const uint8_t *pk) { | |||
AES_XOF_struct G_seedexpander; | |||
uint8_t seed_G[VEC_K_SIZE_BYTES]; | |||
uint8_t diversifier_bytes[8] = {0}; | |||
uint8_t m[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t theta[SEED_BYTES] = {0}; | |||
uint8_t u[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d[SHA512_BYTES] = {0}; | |||
uint8_t mc[VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES] = {0}; | |||
// Computing m | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_from_randombytes(m); | |||
// Generating G function | |||
memcpy(seed_G, m, VEC_K_SIZE_BYTES); | |||
seedexpander_init(&G_seedexpander, seed_G, diversifier_bytes, SEEDEXPANDER_MAX_LENGTH); | |||
// Computing theta | |||
seedexpander(&G_seedexpander, theta, SEED_BYTES); | |||
// Encrypting m | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_pke_encrypt(u, v, m, theta, pk); | |||
// Computing d | |||
sha512(d, m, VEC_K_SIZE_BYTES); | |||
// Computing shared secret | |||
memcpy(mc, m, VEC_K_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES, u, VEC_N_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
sha512(ss, mc, VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES); | |||
// Computing ciphertext | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_ciphertext_to_string(ct, u, v, d); | |||
return 0; | |||
} | |||
/** | |||
* @brief Decapsulation of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* @param[out] ss String containing the shared secret | |||
* @param[in] ct String containing the cipĥertext | |||
* @param[in] sk String containing the secret key | |||
* @returns 0 if decapsulation is successful, -1 otherwise | |||
*/ | |||
int PQCLEAN_HQC1281CCA2_LEAKTIME_crypto_kem_dec(uint8_t *ss, const uint8_t *ct, const uint8_t *sk) { | |||
AES_XOF_struct G_seedexpander; | |||
uint8_t seed_G[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t diversifier_bytes[8] = {0}; | |||
uint8_t u[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d[SHA512_BYTES] = {0}; | |||
uint8_t pk[PUBLIC_KEY_BYTES] = {0}; | |||
uint8_t m[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t theta[SEED_BYTES] = {0}; | |||
uint8_t u2[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v2[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d2[SHA512_BYTES] = {0}; | |||
uint8_t mc[VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES] = {0}; | |||
int8_t abort = 0; | |||
// Retrieving u, v and d from ciphertext | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_ciphertext_from_string(u, v, d, ct); | |||
// Retrieving pk from sk | |||
memcpy(pk, sk + SEED_BYTES, PUBLIC_KEY_BYTES); | |||
// Decryting | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_pke_decrypt(m, u, v, sk); | |||
// Generating G function | |||
memcpy(seed_G, m, VEC_K_SIZE_BYTES); | |||
seedexpander_init(&G_seedexpander, seed_G, diversifier_bytes, SEEDEXPANDER_MAX_LENGTH); | |||
// Computing theta | |||
seedexpander(&G_seedexpander, theta, SEED_BYTES); | |||
// Encrypting m' | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_pke_encrypt(u2, v2, m, theta, pk); | |||
// Checking that c = c' and abort otherwise | |||
if (PQCLEAN_HQC1281CCA2_LEAKTIME_vect_compare(u, u2, VEC_N_SIZE_BYTES) != 0 || | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_compare(v, v2, VEC_N1N2_SIZE_BYTES) != 0) { | |||
abort = 1; | |||
} | |||
// Computing d' | |||
sha512(d2, m, VEC_K_SIZE_BYTES); | |||
// Checking that d = d' and abort otherwise | |||
if (memcmp(d, d2, SHA512_BYTES) != 0) { | |||
abort = 1; | |||
} | |||
if (abort == 1) { | |||
memset(ss, 0, SHARED_SECRET_BYTES); | |||
return -1; | |||
} | |||
// Computing shared secret | |||
memcpy(mc, m, VEC_K_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES, u, VEC_N_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
sha512(ss, mc, VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES); | |||
return 0; | |||
} |
@@ -1,112 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1281CCA2_LEAKTIME_HQC_PARAMETERS_H | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_HQC_PARAMETERS_H | |||
/** | |||
* @file parameters.h | |||
* @brief Parameters of the HQC_KEM IND-CCA2 scheme | |||
*/ | |||
#include "api.h" | |||
#define CEIL_DIVIDE(a, b) (((a)/(b)) + ((a) % (b) == 0 ? 0 : 1)) /*!< Divide a by b and ceil the result*/ | |||
#define BITMASK(a, size) ((1ULL << ((a) % (size))) - 1) /*!< Create a mask*/ | |||
/* | |||
#define PARAM_N Define the parameter n of the scheme | |||
#define PARAM_N1 Define the parameter n1 of the scheme (length of BCH code) | |||
#define PARAM_N2 Define the parameter n2 of the scheme (length of the repetition code) | |||
#define PARAM_N1N2 Define the parameter n1 * n2 of the scheme (length of the tensor code) | |||
#define PARAM_OMEGA Define the parameter omega of the scheme | |||
#define PARAM_OMEGA_E Define the parameter omega_e of the scheme | |||
#define PARAM_OMEGA_R Define the parameter omega_r of the scheme | |||
#define PARAM_SECURITY Define the security level corresponding to the chosen parameters | |||
#define PARAM_DFR_EXP Define the decryption failure rate corresponding to the chosen parameters | |||
#define SECRET_KEY_BYTES Define the size of the secret key in bytes | |||
#define PUBLIC_KEY_BYTES Define the size of the public key in bytes | |||
#define SHARED_SECRET_BYTES Define the size of the shared secret in bytes | |||
#define CIPHERTEXT_BYTES Define the size of the ciphertext in bytes | |||
#define UTILS_REJECTION_THRESHOLD Define the rejection threshold used to generate given weight vectors (see vector_set_random_fixed_weight function) | |||
#define VEC_N_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N sized vector in bytes | |||
#define VEC_N1_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N1 sized vector in bytes | |||
#define VEC_N1N2_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N1N2 sized vector in bytes | |||
#define VEC_K_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_K sized vector in bytes | |||
#define PARAM_T Define a threshold for decoding repetition code word (PARAM_T = (PARAM_N2 - 1) / 2) | |||
#define PARAM_DELTA Define the parameter delta of the scheme (correcting capacity of the BCH code) | |||
#define PARAM_M Define a positive integer | |||
#define PARAM_GF_MUL_ORDER Define the size of the multiplicative group of GF(2^m), i.e 2^m -1 | |||
#define PARAM_K Define the size of the information bits of the BCH code | |||
#define PARAM_G Define the size of the generator polynomial of BCH code | |||
#define PARAM_FFT The additive FFT takes a 2^PARAM_FFT polynomial as input | |||
We use the FFT to compute the roots of sigma, whose degree if PARAM_DELTA=60 | |||
The smallest power of 2 greater than 60+1 is 64=2^6 | |||
#define PARAM_FFT_T The additive FFT transpose computes a (2^PARAM_FFT_T)-sized syndrome vector | |||
We want to compute 2*PARAM_DELTA=120 syndromes | |||
The smallest power of 2 greater than 120 is 2^7 | |||
#define PARAM_BCH_POLY Generator polynomial of the BCH code | |||
#define SHA512_BYTES Define the size of SHA512 output in bytes | |||
#define SEED_BYTES Define the size of the seed in bytes | |||
#define SEEDEXPANDER_MAX_LENGTH Define the seed expander max length | |||
*/ | |||
#define PARAM_N 24677 | |||
#define PARAM_N1 796 | |||
#define PARAM_N2 31 | |||
#define PARAM_N1N2 24676 | |||
#define PARAM_OMEGA 67 | |||
#define PARAM_OMEGA_E 77 | |||
#define PARAM_OMEGA_R 77 | |||
#define PARAM_SECURITY 128 | |||
#define PARAM_DFR_EXP 128 | |||
#define SECRET_KEY_BYTES PQCLEAN_HQC1281CCA2_LEAKTIME_CRYPTO_SECRETKEYBYTES | |||
#define PUBLIC_KEY_BYTES PQCLEAN_HQC1281CCA2_LEAKTIME_CRYPTO_PUBLICKEYBYTES | |||
#define SHARED_SECRET_BYTES PQCLEAN_HQC1281CCA2_LEAKTIME_CRYPTO_BYTES | |||
#define CIPHERTEXT_BYTES PQCLEAN_HQC1281CCA2_LEAKTIME_CRYPTO_CIPHERTEXTBYTES | |||
#define UTILS_REJECTION_THRESHOLD 16755683 | |||
#define VEC_K_SIZE_BYTES CEIL_DIVIDE(PARAM_K, 8) | |||
#define VEC_N_SIZE_BYTES CEIL_DIVIDE(PARAM_N, 8) | |||
#define VEC_N1_SIZE_BYTES CEIL_DIVIDE(PARAM_N1, 8) | |||
#define VEC_N1N2_SIZE_BYTES CEIL_DIVIDE(PARAM_N1N2, 8) | |||
#define PARAM_T 15 | |||
#define PARAM_DELTA 60 | |||
#define PARAM_M 10 | |||
#define PARAM_GF_MUL_ORDER 1023 | |||
#define PARAM_K 256 | |||
#define PARAM_G 541 | |||
#define PARAM_FFT 6 | |||
#define PARAM_FFT_T 7 | |||
#define PARAM_BCH_POLY { \ | |||
1,1,0,1,1,0,1,0,0,0,0,1,0,1,0,1,1,1,1,1,1,0,1,1,0,1,1,1,1,1,0,0, \ | |||
1,0,0,1,0,1,1,0,1,0,0,1,1,1,0,0,1,1,1,0,0,0,1,0,1,0,1,0,1,1,0,0, \ | |||
1,0,1,0,0,1,0,0,0,1,1,1,1,1,1,1,0,0,1,1,1,1,0,1,0,1,0,1,1,0,1,0, \ | |||
0,1,0,1,1,1,0,0,0,1,1,1,1,0,0,0,1,0,1,1,1,1,0,1,0,0,1,1,1,1,0,1, \ | |||
0,0,0,1,0,0,1,1,1,1,1,0,1,0,0,0,1,0,1,1,0,0,0,1,0,1,0,0,1,0,0,0, \ | |||
1,1,0,1,0,1,0,1,1,0,1,1,0,0,1,1,1,0,0,1,0,1,0,0,1,0,0,1,1,0,1,0, \ | |||
0,0,0,1,1,0,0,0,0,1,0,1,1,0,1,1,0,1,0,0,0,1,1,1,0,1,0,1,1,0,0,1, \ | |||
1,0,1,1,0,0,0,1,0,1,1,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,1,1,0,0,1,0, \ | |||
0,0,1,1,0,0,1,1,1,0,0,0,1,0,0,1,1,1,1,0,0,0,0,0,1,1,0,0,1,0,1,1, \ | |||
1,1,1,1,0,1,1,1,0,0,1,1,0,0,1,1,1,1,1,0,0,0,0,1,0,1,1,1,0,1,0,1, \ | |||
0,0,0,0,1,1,0,0,0,0,1,0,0,0,1,0,1,0,1,0,1,1,0,0,0,1,0,1,1,0,0,0, \ | |||
1,0,0,1,0,0,1,1,0,0,1,0,1,0,0,1,1,1,1,0,0,1,1,0,0,1,1,0,1,0,1,1, \ | |||
0,0,0,0,0,0,0,0,1,0,1,1,0,0,0,0,0,0,1,1,0,1,0,1,0,0,0,0,0,1,1,1, \ | |||
0,1,0,1,1,0,1,1,1,1,0,1,1,1,0,1,1,0,1,1,1,1,1,0,0,1,0,0,1,1,0,0, \ | |||
0,0,0,0,1,0,1,0,0,0,0,0,1,0,1,1,1,1,1,0,0,1,1,1,0,0,0,0,1,0,1,1, \ | |||
1,1,0,0,1,0,0,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,0,1,0,1,1,0,1,0,0, \ | |||
1,0,1,1,0,0,0,0,0,1,1,1,1,0,1,0,0,1,0,0,0,0,1,0,0,0,0,0,1 \ | |||
}; | |||
#define SHA512_BYTES 64 | |||
#define SEED_BYTES 40 | |||
#define SEEDEXPANDER_MAX_LENGTH 4294967295 | |||
#endif |
@@ -1,126 +0,0 @@ | |||
/** | |||
* @file parsing.c | |||
* @brief Functions to parse secret key, public key and ciphertext of the HQC scheme | |||
*/ | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
/** | |||
* @brief Parse a secret key into a string | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] sk String containing the secret key | |||
* @param[in] sk_seed Seed used to generate the secret key | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_secret_key_to_string(uint8_t *sk, const uint8_t *sk_seed, const uint8_t *pk) { | |||
memcpy(sk, sk_seed, SEED_BYTES); | |||
memcpy(sk + SEED_BYTES, pk, PUBLIC_KEY_BYTES); | |||
} | |||
/** | |||
* @brief Parse a secret key from a string | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] x uint8_t representation of vector x | |||
* @param[out] y uint8_t representation of vector y | |||
* @param[out] pk String containing the public key | |||
* @param[in] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_secret_key_from_string(uint8_t *x, uint32_t *y, uint8_t *pk, const uint8_t *sk) { | |||
AES_XOF_struct sk_seedexpander; | |||
uint8_t sk_seed[SEED_BYTES] = {0}; | |||
memcpy(sk_seed, sk, SEED_BYTES); | |||
seedexpander_init(&sk_seedexpander, sk_seed, sk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_fixed_weight(&sk_seedexpander, x, PARAM_OMEGA); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&sk_seedexpander, y, PARAM_OMEGA); | |||
memcpy(pk, sk + SEED_BYTES, PUBLIC_KEY_BYTES); | |||
} | |||
/** | |||
* @brief Parse a public key into a string | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b> | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[in] pk_seed Seed used to generate the public key | |||
* @param[in] s uint8_t representation of vector s | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_public_key_to_string(uint8_t *pk, const uint8_t *pk_seed, const uint8_t *s) { | |||
memcpy(pk, pk_seed, SEED_BYTES); | |||
memcpy(pk + SEED_BYTES, s, VEC_N_SIZE_BYTES); | |||
} | |||
/** | |||
* @brief Parse a public key from a string | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b> | |||
* | |||
* @param[out] h uint8_t representation of vector h | |||
* @param[out] s uint8_t representation of vector s | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_public_key_from_string(uint8_t *h, uint8_t *s, const uint8_t *pk) { | |||
AES_XOF_struct pk_seedexpander; | |||
uint8_t pk_seed[SEED_BYTES] = {0}; | |||
memcpy(pk_seed, pk, SEED_BYTES); | |||
seedexpander_init(&pk_seedexpander, pk_seed, pk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random(&pk_seedexpander, h); | |||
memcpy(s, pk + SEED_BYTES, VEC_N_SIZE_BYTES); | |||
} | |||
/** | |||
* @brief Parse a ciphertext into a string | |||
* | |||
* The ciphertext is composed of vectors <b>u</b>, <b>v</b> and hash <b>d</b>. | |||
* | |||
* @param[out] ct String containing the ciphertext | |||
* @param[in] u uint8_t representation of vector u | |||
* @param[in] v uint8_t representation of vector v | |||
* @param[in] d String containing the hash d | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_ciphertext_to_string(uint8_t *ct, const uint8_t *u, const uint8_t *v, const uint8_t *d) { | |||
memcpy(ct, u, VEC_N_SIZE_BYTES); | |||
memcpy(ct + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
memcpy(ct + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES, d, SHA512_BYTES); | |||
} | |||
/** | |||
* @brief Parse a ciphertext from a string | |||
* | |||
* The ciphertext is composed of vectors <b>u</b>, <b>v</b> and hash <b>d</b>. | |||
* | |||
* @param[out] u uint8_t representation of vector u | |||
* @param[out] v uint8_t representation of vector v | |||
* @param[out] d String containing the hash d | |||
* @param[in] ct String containing the ciphertext | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_ciphertext_from_string(uint8_t *u, uint8_t *v, uint8_t *d, const uint8_t *ct) { | |||
memcpy(u, ct, VEC_N_SIZE_BYTES); | |||
memcpy(v, ct + VEC_N_SIZE_BYTES, VEC_N1N2_SIZE_BYTES); | |||
memcpy(d, ct + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES, SHA512_BYTES); | |||
} |
@@ -1,20 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1281CCA2_LEAKTIME_PARSING_H | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_PARSING_H | |||
/** | |||
* @file parsing.h | |||
* @brief Header file for parsing.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_secret_key_to_string(uint8_t *sk, const uint8_t *sk_seed, const uint8_t *pk); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_secret_key_from_string(uint8_t *x, uint32_t *y, uint8_t *pk, const uint8_t *sk); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_public_key_to_string(uint8_t *pk, const uint8_t *pk_seed, const uint8_t *s); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_public_key_from_string(uint8_t *h, uint8_t *s, const uint8_t *pk); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_ciphertext_to_string(uint8_t *ct, const uint8_t *u, const uint8_t *v, const uint8_t *d); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_hqc_ciphertext_from_string(uint8_t *u, uint8_t *v, uint8_t *d, const uint8_t *ct); | |||
#endif |
@@ -1,100 +0,0 @@ | |||
/** | |||
* @file repetition.c | |||
* @brief Implementation of repetition codes | |||
*/ | |||
#include "parameters.h" | |||
#include "repetition.h" | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
static void array_to_rep_codeword(uint8_t *o, const uint8_t *v); | |||
/** | |||
* @brief Encoding each bit in the message m using the repetition code | |||
* | |||
* For reasons of clarity and comprehensibility, we do the encoding by storing the encoded bits in a String (each bit in an a uint8_t), | |||
* then we parse the obtained string to an compact array using the function array_to_rep_codeword(). | |||
* | |||
* @param[out] em Pointer to an array that is the code word | |||
* @param[in] m Pointer to an array that is the message | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_repetition_code_encode(uint8_t *em, const uint8_t *m) { | |||
uint8_t tmp[PARAM_N1N2] = {0}; | |||
uint8_t bit = 0; | |||
uint32_t index; | |||
for (size_t i = 0; i < (VEC_N1_SIZE_BYTES - 1); ++i) { | |||
for (uint8_t j = 0; j < 8; ++j) { | |||
bit = (m[i] >> j) & 0x01; | |||
index = (8 * (uint32_t)i + j) * PARAM_N2; | |||
for (uint8_t k = 0; k < PARAM_N2; ++k) { | |||
tmp[index + k] = bit; | |||
} | |||
} | |||
} | |||
for (uint8_t j = 0; j < (PARAM_N1 % 8); ++j) { | |||
bit = (m[VEC_N1_SIZE_BYTES - 1] >> j) & 0x01; | |||
index = (8 * (VEC_N1_SIZE_BYTES - 1) + j) * PARAM_N2; | |||
for (uint8_t k = 0; k < PARAM_N2; ++k) { | |||
tmp[index + k] = bit; | |||
} | |||
} | |||
array_to_rep_codeword(em, tmp); | |||
} | |||
/** | |||
* @brief Decoding the code words to a message using the repetition code | |||
* | |||
* We use a majority decoding. In fact we have that PARAM_N2 = 2 * PARAM_T + 1, thus, | |||
* if the Hamming weight of the vector is greater than PARAM_T, the code word is decoded | |||
* to 1 and 0 otherwise. | |||
* | |||
* @param[out] m Pointer to an array that is the message | |||
* @param[in] em Pointer to an array that is the code word | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_repetition_code_decode(uint8_t *m, const uint8_t *em) { | |||
size_t t = 0; // m index | |||
uint8_t k = PARAM_N2; // block counter | |||
uint8_t ones = 0; // number of 1 in the current block | |||
for (size_t i = 0; i < VEC_N1N2_SIZE_BYTES; ++i) { | |||
for (uint8_t j = 0; j < 8; ++j) { | |||
ones += (em[i] >> j) & 0x01; | |||
if (--k) { | |||
continue; | |||
} | |||
m[t / 8] |= (ones > PARAM_T) << t % 8; | |||
++t; | |||
k = PARAM_N2; | |||
ones = 0; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Parse an array to an compact array | |||
* | |||
* @param[out] o Pointer to an array | |||
* @param[in] v Pointer to an array | |||
*/ | |||
static void array_to_rep_codeword(uint8_t *o, const uint8_t *v) { | |||
for (size_t i = 0; i < (VEC_N1N2_SIZE_BYTES - 1); ++i) { | |||
for (uint8_t j = 0; j < 8; ++j) { | |||
o[i] |= v[j + 8 * i] << j; | |||
} | |||
} | |||
for (uint8_t j = 0; j < PARAM_N1N2 % 8; ++j) { | |||
o[VEC_N1N2_SIZE_BYTES - 1] |= (v[j + 8 * (VEC_N1N2_SIZE_BYTES - 1)]) << j; | |||
} | |||
} |
@@ -1,14 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1281CCA2_LEAKTIME_REPETITION_H | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_REPETITION_H | |||
/** | |||
* @file repetition.h | |||
* @brief Header file for repetition.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_repetition_code_encode(uint8_t *em, const uint8_t *m); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_repetition_code_decode(uint8_t *m, const uint8_t *em); | |||
#endif |
@@ -1,42 +0,0 @@ | |||
/** | |||
* @file tensor.c | |||
* @brief Implementation of tensor code | |||
*/ | |||
#include "bch.h" | |||
#include "parameters.h" | |||
#include "repetition.h" | |||
#include "tensor.h" | |||
#include <stdint.h> | |||
/** | |||
* @brief Encoding the message m to a code word em using the tensor code | |||
* | |||
* First we encode the message using the BCH code, then with the repetition code to obtain | |||
* a tensor code word. | |||
* | |||
* @param[out] em Pointer to an array that is the tensor code word | |||
* @param[in] m Pointer to an array that is the message | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_tensor_code_encode(uint8_t *em, const uint8_t *m) { | |||
uint8_t tmp[VEC_N1_SIZE_BYTES] = {0}; | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_bch_code_encode(tmp, m); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_repetition_code_encode(em, tmp); | |||
} | |||
/** | |||
* @brief Decoding the code word em to a message m using the tensor code | |||
* | |||
* @param[out] m Pointer to an array that is the message | |||
* @param[in] em Pointer to an array that is the code word | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_tensor_code_decode(uint8_t *m, const uint8_t *em) { | |||
uint8_t tmp[VEC_N1_SIZE_BYTES] = {0}; | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_repetition_code_decode(tmp, em); | |||
PQCLEAN_HQC1281CCA2_LEAKTIME_bch_code_decode(m, tmp); | |||
} |
@@ -1,14 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1281CCA2_LEAKTIME_TENSOR_H | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_TENSOR_H | |||
/** | |||
* @file tensor.h | |||
* @brief Header file for tensor.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_tensor_code_encode(uint8_t *em, const uint8_t *m); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_tensor_code_decode(uint8_t *m, const uint8_t *em); | |||
#endif |
@@ -1,69 +0,0 @@ | |||
#include "util.h" | |||
#include "stddef.h" | |||
#include "assert.h" | |||
/* These functions should help with endianness-safe conversions | |||
* | |||
* load8 and store8 are copied from the McEliece implementations, | |||
* which are in the public domain. | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_store8(unsigned char *out, uint64_t in) { | |||
out[0] = (in >> 0x00) & 0xFF; | |||
out[1] = (in >> 0x08) & 0xFF; | |||
out[2] = (in >> 0x10) & 0xFF; | |||
out[3] = (in >> 0x18) & 0xFF; | |||
out[4] = (in >> 0x20) & 0xFF; | |||
out[5] = (in >> 0x28) & 0xFF; | |||
out[6] = (in >> 0x30) & 0xFF; | |||
out[7] = (in >> 0x38) & 0xFF; | |||
} | |||
uint64_t PQCLEAN_HQC1281CCA2_LEAKTIME_load8(const unsigned char *in) { | |||
uint64_t ret = in[7]; | |||
for (int8_t i = 6; i >= 0; i--) { | |||
ret <<= 8; | |||
ret |= in[i]; | |||
} | |||
return ret; | |||
} | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_load8_arr(uint64_t *out64, size_t outlen, const uint8_t *in8, size_t inlen) { | |||
size_t index_in = 0; | |||
size_t index_out = 0; | |||
// first copy by 8 bytes | |||
if (inlen >= 8 && outlen >= 1) { | |||
while (index_out < outlen && index_in + 8 <= inlen) { | |||
out64[index_out] = PQCLEAN_HQC1281CCA2_LEAKTIME_load8(in8 + index_in); | |||
index_in += 8; | |||
index_out += 1; | |||
} | |||
} | |||
// we now need to do the last 7 bytes if necessary | |||
if (index_in >= inlen || index_out >= outlen) { | |||
return; | |||
} | |||
out64[index_out] = in8[inlen - 1]; | |||
for (int8_t i = (int8_t)(inlen - index_in) - 2; i >= 0; i--) { | |||
out64[index_out] <<= 8; | |||
out64[index_out] |= in8[index_in + i]; | |||
} | |||
} | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_store8_arr(uint8_t *out8, size_t outlen, const uint64_t *in64, size_t inlen) { | |||
for (size_t index_out = 0, index_in = 0; index_out < outlen && index_in < inlen;) { | |||
out8[index_out] = (in64[index_in] >> ((index_out % 8) * 8)) & 0xFF; | |||
index_out++; | |||
if (index_out % 8 == 0) { | |||
index_in++; | |||
} | |||
} | |||
} |
@@ -1,9 +0,0 @@ | |||
/* These functions should help with endianness-safe conversions */ | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_store8(unsigned char *out, uint64_t in); | |||
uint64_t PQCLEAN_HQC1281CCA2_LEAKTIME_load8(const unsigned char *in); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_load8_arr(uint64_t *out64, size_t outlen, const uint8_t *in8, size_t inlen); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_store8_arr(uint8_t *out8, size_t outlen, const uint64_t *in64, size_t inlen); |
@@ -1,224 +0,0 @@ | |||
/** | |||
* @file vector.c | |||
* @brief Implementation of vectors sampling and some utilities for the HQC scheme | |||
*/ | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "randombytes.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
/** | |||
* @brief Generates a vector of a given Hamming weight | |||
* | |||
* This function generates uniformly at random a binary vector of a Hamming weight equal to the parameter <b>weight</b>. The vector | |||
* is stored by position. | |||
* To generate the vector we have to sample uniformly at random values in the interval [0, PARAM_N -1]. Suppose the PARAM_N is equal to \f$ 70853 \f$, to select a position \f$ r\f$ the function works as follow: | |||
* 1. It makes a call to the seedexpander function to obtain a random number \f$ x\f$ in \f$ [0, 2^{24}[ \f$. | |||
* 2. Let \f$ t = \lfloor {2^{24} \over 70853} \rfloor \times 70853\f$ | |||
* 3. If \f$ x \geq t\f$, go to 1 | |||
* 4. It return \f$ r = x \mod 70853\f$ | |||
* | |||
* The parameter \f$ t \f$ is precomputed and it's denoted by UTILS_REJECTION_THRESHOLD (see the file parameters.h). | |||
* | |||
* @param[in] v Pointer to an array | |||
* @param[in] weight Integer that is the Hamming weight | |||
* @param[in] ctx Pointer to the context of the seed expander | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(AES_XOF_struct *ctx, uint32_t *v, uint16_t weight) { | |||
size_t random_bytes_size = 3 * weight; | |||
uint8_t rand_bytes[3 * PARAM_OMEGA_R] = {0}; // weight is expected to be <= PARAM_OMEGA_R | |||
uint32_t random_data = 0; | |||
uint8_t exist = 0; | |||
size_t j = 0; | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
for (uint32_t i = 0; i < weight; ++i) { | |||
exist = 0; | |||
do { | |||
if (j == random_bytes_size) { | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
j = 0; | |||
} | |||
random_data = ((uint32_t) rand_bytes[j++]) << 16; | |||
random_data |= ((uint32_t) rand_bytes[j++]) << 8; | |||
random_data |= rand_bytes[j++]; | |||
} while (random_data >= UTILS_REJECTION_THRESHOLD); | |||
random_data = random_data % PARAM_N; | |||
for (uint32_t k = 0; k < i; k++) { | |||
if (v[k] == random_data) { | |||
exist = 1; | |||
} | |||
} | |||
if (exist == 1) { | |||
i--; | |||
} else { | |||
v[i] = random_data; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Generates a vector of a given Hamming weight | |||
* | |||
* This function generates uniformly at random a binary vector of a Hamming weight equal to the parameter <b>weight</b>. | |||
* To generate the vector we have to sample uniformly at random values in the interval [0, PARAM_N -1]. Suppose the PARAM_N is equal to \f$ 70853 \f$, to select a position \f$ r\f$ the function works as follow: | |||
* 1. It makes a call to the seedexpander function to obtain a random number \f$ x\f$ in \f$ [0, 2^{24}[ \f$. | |||
* 2. Let \f$ t = \lfloor {2^{24} \over 70853} \rfloor \times 70853\f$ | |||
* 3. If \f$ x \geq t\f$, go to 1 | |||
* 4. It return \f$ r = x \mod 70853\f$ | |||
* | |||
* The parameter \f$ t \f$ is precomputed and it's denoted by UTILS_REJECTION_THRESHOLD (see the file parameters.h). | |||
* | |||
* @param[in] v Pointer to an array | |||
* @param[in] weight Integer that is the Hamming weight | |||
* @param[in] ctx Pointer to the context of the seed expander | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_fixed_weight(AES_XOF_struct *ctx, uint8_t *v, uint16_t weight) { | |||
size_t random_bytes_size = 3 * weight; | |||
uint8_t rand_bytes[3 * PARAM_OMEGA_R] = {0}; // weight is expected to be <= PARAM_OMEGA_R | |||
uint32_t random_data = 0; | |||
uint32_t tmp[PARAM_OMEGA_R] = {0}; | |||
uint8_t exist = 0; | |||
size_t j = 0; | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
for (uint32_t i = 0; i < weight; ++i) { | |||
exist = 0; | |||
do { | |||
if (j == random_bytes_size) { | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
j = 0; | |||
} | |||
random_data = ((uint32_t) rand_bytes[j++]) << 16; | |||
random_data |= ((uint32_t) rand_bytes[j++]) << 8; | |||
random_data |= rand_bytes[j++]; | |||
} while (random_data >= UTILS_REJECTION_THRESHOLD); | |||
random_data = random_data % PARAM_N; | |||
for (uint32_t k = 0; k < i; k++) { | |||
if (tmp[k] == random_data) { | |||
exist = 1; | |||
} | |||
} | |||
if (exist == 1) { | |||
i--; | |||
} else { | |||
tmp[i] = random_data; | |||
} | |||
} | |||
for (uint16_t i = 0; i < weight; ++i) { | |||
int32_t index = tmp[i] / 8; | |||
int32_t pos = tmp[i] % 8; | |||
v[index] |= 1 << pos; | |||
} | |||
} | |||
/** | |||
* @brief Generates a random vector of dimension <b>PARAM_N</b> | |||
* | |||
* This function generates a random binary vector of dimension <b>PARAM_N</b>. It generates a random | |||
* array of bytes using the seedexpander function, and drop the extra bits using a mask. | |||
* | |||
* @param[in] v Pointer to an array | |||
* @param[in] ctx Pointer to the context of the seed expander | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random(AES_XOF_struct *ctx, uint8_t *v) { | |||
uint8_t rand_bytes[VEC_N_SIZE_BYTES] = {0}; | |||
seedexpander(ctx, rand_bytes, VEC_N_SIZE_BYTES); | |||
memcpy(v, rand_bytes, VEC_N_SIZE_BYTES); | |||
v[VEC_N_SIZE_BYTES - 1] &= BITMASK(PARAM_N, 8); | |||
} | |||
/** | |||
* @brief Generates a random vector | |||
* | |||
* This function generates a random binary vector. It uses the the randombytes function. | |||
* | |||
* @param[in] v Pointer to an array | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_from_randombytes(uint8_t *v) { | |||
uint8_t rand_bytes [VEC_K_SIZE_BYTES] = {0}; | |||
randombytes(rand_bytes, VEC_K_SIZE_BYTES); | |||
memcpy(v, rand_bytes, VEC_K_SIZE_BYTES); | |||
} | |||
/** | |||
* @brief Adds two vectors | |||
* | |||
* @param[out] o Pointer to an array that is the result | |||
* @param[in] v1 Pointer to an array that is the first vector | |||
* @param[in] v2 Pointer to an array that is the second vector | |||
* @param[in] size Integer that is the size of the vectors | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_add(uint8_t *o, const uint8_t *v1, const uint8_t *v2, uint32_t size) { | |||
for (uint32_t i = 0; i < size; ++i) { | |||
o[i] = v1[i] ^ v2[i]; | |||
} | |||
} | |||
/** | |||
* @brief Compares two vectors | |||
* | |||
* @param[in] v1 Pointer to an array that is first vector | |||
* @param[in] v2 Pointer to an array that is second vector | |||
* @param[in] size Integer that is the size of the vectors | |||
* @returns 0 if the vectors are equals and a negative/psotive value otherwise | |||
*/ | |||
int PQCLEAN_HQC1281CCA2_LEAKTIME_vect_compare(const uint8_t *v1, const uint8_t *v2, uint32_t size) { | |||
return memcmp(v1, v2, size); | |||
} | |||
/** | |||
* @brief Resize a vector so that it contains <b>size_o</b> bits | |||
* | |||
* @param[out] o Pointer to the output vector | |||
* @param[in] size_o Integer that is the size of the output vector in bits | |||
* @param[in] v Pointer to the input vector | |||
* @param[in] size_v Integer that is the size of the input vector in bits | |||
*/ | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_resize(uint8_t *o, uint32_t size_o, const uint8_t *v, uint32_t size_v) { | |||
if (size_o < size_v) { | |||
uint8_t mask = 0x7F; | |||
int8_t val = 8 - (size_o % 8); | |||
memcpy(o, v, VEC_N1N2_SIZE_BYTES); | |||
for (int8_t i = 0; i < val; ++i) { | |||
o[VEC_N1N2_SIZE_BYTES - 1] &= (mask >> i); | |||
} | |||
} else { | |||
memcpy(o, v, CEIL_DIVIDE(size_v, 8)); | |||
} | |||
} |
@@ -1,22 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1281CCA2_LEAKTIME_VECTOR_H | |||
#define PQCLEAN_HQC1281CCA2_LEAKTIME_VECTOR_H | |||
/** | |||
* @file vector.h | |||
* @brief Header file for vector.c | |||
*/ | |||
#include "nistseedexpander.h" | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(AES_XOF_struct *ctx, uint32_t *v, uint16_t weight); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_fixed_weight(AES_XOF_struct *ctx, uint8_t *v, uint16_t weight); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random(AES_XOF_struct *ctx, uint8_t *v); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_set_random_from_randombytes(uint8_t *v); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_add(uint8_t *o, const uint8_t *v1, const uint8_t *v2, uint32_t size); | |||
int PQCLEAN_HQC1281CCA2_LEAKTIME_vect_compare(const uint8_t *v1, const uint8_t *v2, uint32_t size); | |||
void PQCLEAN_HQC1281CCA2_LEAKTIME_vect_resize(uint8_t *o, uint32_t size_o, const uint8_t *v, uint32_t size_v); | |||
#endif |
@@ -1,23 +0,0 @@ | |||
name: HQC_192_1_CCA2 | |||
type: kem | |||
claimed-nist-level: 3 | |||
claimed-security: IND-CCA2 | |||
length-public-key: 5499 | |||
length-ciphertext: 10981 | |||
length-secret-key: 5539 | |||
length-shared-secret: 64 | |||
nistkat-sha256: ddff72bfd7bf33a9fa1b3c70a05378b0544e57207b5bb9205cacd6d69002d597 | |||
principal-submitters: | |||
- Carlos Aguilar Melchor | |||
- Nicolas Aragon | |||
- Slim Bettaieb | |||
- Loïc Bidoux | |||
- Olivier Blazy | |||
- Jean-Christophe Deneuville | |||
- Philippe Gaborit | |||
- Edoardo Persichetti | |||
- Gilles Zémor | |||
auxiliary-submitters: [] | |||
implementations: | |||
- name: leaktime | |||
version: https://pqc-hqc.org/doc/hqc-reference-implementation_2019-08-24.zip |
@@ -1 +0,0 @@ | |||
Public domain |
@@ -1,19 +0,0 @@ | |||
# This Makefile can be used with GNU Make or BSD Make | |||
LIB=libhqc-192-1-cca2_leaktime.a | |||
HEADERS=api.h bch.h fft.h gf.h gf2x.h hqc.h parameters.h parsing.h repetition.h tensor.h vector.h util.h | |||
OBJECTS=bch.o fft.o gf.o gf2x.o hqc.o kem.o parsing.o repetition.o tensor.o vector.o util.o | |||
CFLAGS=-O3 -Wall -Wextra -Wpedantic -Wvla -Werror -Wmissing-prototypes -Wredundant-decls -std=c99 -I../../../common $(EXTRAFLAGS) | |||
all: $(LIB) | |||
%.o: %.c $(HEADERS) | |||
$(CC) $(CFLAGS) -c -o $@ $< | |||
$(LIB): $(OBJECTS) | |||
$(AR) -r $@ $(OBJECTS) | |||
clean: | |||
$(RM) $(OBJECTS) | |||
$(RM) $(LIB) |
@@ -1,23 +0,0 @@ | |||
# This Makefile can be used with Microsoft Visual Studio's nmake using the command: | |||
# nmake /f Makefile.Microsoft_nmake | |||
LIBRARY=libhqc-192-1-cca2_leaktime.lib | |||
OBJECTS=bch.obj fft.obj gf.obj gf2x.obj hqc.obj kem.obj parsing.obj repetition.obj tensor.obj vector.obj util.obj | |||
# We ignore warning C4127: we sometimes use a conditional that depending | |||
# on the parameters results in a case where if (const) is the case. | |||
# The compiler should just optimise this away, but on MSVC we get | |||
# a compiler complaint. | |||
CFLAGS=/nologo /O2 /I ..\..\..\common /W4 /WX /wd4127 | |||
all: $(LIBRARY) | |||
# Make sure objects are recompiled if headers change. | |||
$(OBJECTS): *.h | |||
$(LIBRARY): $(OBJECTS) | |||
LIB.EXE /NOLOGO /WX /OUT:$@ $** | |||
clean: | |||
-DEL $(OBJECTS) | |||
-DEL $(LIBRARY) |
@@ -1,25 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1921CCA2_LEAKTIME_API_H | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_API_H | |||
/** | |||
* \file api.h | |||
* \brief NIST KEM API used by the HQC_KEM IND-CCA2 scheme | |||
*/ | |||
#include <stdint.h> | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_CRYPTO_ALGNAME "HQC_192_1_CCA2" | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_CRYPTO_SECRETKEYBYTES 5539 | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_CRYPTO_PUBLICKEYBYTES 5499 | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_CRYPTO_BYTES 64 | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_CRYPTO_CIPHERTEXTBYTES 10981 | |||
// As a technicality, the public key is appended to the secret key in order to respect the NIST API. | |||
// Without this constraint, CRYPTO_SECRETKEYBYTES would be defined as 32 | |||
int PQCLEAN_HQC1921CCA2_LEAKTIME_crypto_kem_keypair(uint8_t *pk, uint8_t *sk); | |||
int PQCLEAN_HQC1921CCA2_LEAKTIME_crypto_kem_enc(uint8_t *ct, uint8_t *ss, const uint8_t *pk); | |||
int PQCLEAN_HQC1921CCA2_LEAKTIME_crypto_kem_dec(uint8_t *ss, const uint8_t *ct, const uint8_t *sk); | |||
#endif |
@@ -1,295 +0,0 @@ | |||
/** | |||
* @file bch.c | |||
* Constant time implementation of BCH codes | |||
*/ | |||
#include "bch.h" | |||
#include "fft.h" | |||
#include "gf.h" | |||
#include "parameters.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
static void unpack_message(uint8_t *message_unpacked, const uint8_t *message); | |||
static void lfsr_encode(uint8_t *codeword, const uint8_t *message); | |||
static void pack_codeword(uint8_t *codeword, const uint8_t *codeword_unpacked); | |||
static size_t compute_elp(uint16_t *sigma, const uint16_t *syndromes); | |||
static void message_from_codeword(uint8_t *message, const uint8_t *codeword); | |||
static void compute_syndromes(uint16_t *syndromes, const uint8_t *vector); | |||
static void compute_roots(uint8_t *error, const uint16_t *sigma); | |||
/** | |||
* @brief Unpacks the message message to the array message_unpacked where each byte stores a bit of the message | |||
* | |||
* @param[out] message_unpacked Array of VEC_K_SIZE_BYTES bytes receiving the unpacked message | |||
* @param[in] message Array of PARAM_K bytes storing the packed message | |||
*/ | |||
static void unpack_message(uint8_t *message_unpacked, const uint8_t *message) { | |||
for (size_t i = 0; i < (VEC_K_SIZE_BYTES - (PARAM_K % 8 != 0)); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
message_unpacked[j + 8 * i] = (message[i] >> j) & 0x01; | |||
} | |||
} | |||
for (int8_t j = 0; j < PARAM_K % 8; ++j) { | |||
message_unpacked[j + 8 * (VEC_K_SIZE_BYTES - 1)] = (message[VEC_K_SIZE_BYTES - 1] >> j) & 0x01; | |||
} | |||
} | |||
/** | |||
* @brief Encodes the message message to a codeword codeword using the generator polynomial bch_poly of the code | |||
* | |||
* @param[out] codeword Array of PARAM_N1 bytes receiving the codeword | |||
* @param[in] message Array of PARAM_K bytes storing the message to encode | |||
*/ | |||
static void lfsr_encode(uint8_t *codeword, const uint8_t *message) { | |||
uint8_t gate_value = 0; | |||
uint8_t bch_poly[PARAM_G] = PARAM_BCH_POLY; | |||
// Compute the Parity-check digits | |||
for (int16_t i = PARAM_K - 1; i >= 0; --i) { | |||
gate_value = message[i] ^ codeword[PARAM_N1 - PARAM_K - 1]; | |||
for (size_t j = PARAM_N1 - PARAM_K - 1; j; --j) { | |||
codeword[j] = codeword[j - 1] ^ (-gate_value & bch_poly[j]); | |||
} | |||
codeword[0] = gate_value; | |||
} | |||
// Add the message | |||
memcpy(codeword + PARAM_N1 - PARAM_K, message, PARAM_K); | |||
} | |||
/** | |||
* @brief Packs the codeword from an array codeword_unpacked where each byte stores a bit to a compact array codeword | |||
* | |||
* @param[out] codeword Array of VEC_N1_SIZE_BYTES bytes receiving the packed codeword | |||
* @param[in] codeword_unpacked Array of PARAM_N1 bytes storing the unpacked codeword | |||
*/ | |||
static void pack_codeword(uint8_t *codeword, const uint8_t *codeword_unpacked) { | |||
for (size_t i = 0; i < (VEC_N1_SIZE_BYTES - (PARAM_N1 % 8 != 0)); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
codeword[i] |= codeword_unpacked[j + 8 * i] << j; | |||
} | |||
} | |||
for (size_t j = 0; j < PARAM_N1 % 8; ++j) { | |||
codeword[VEC_N1_SIZE_BYTES - 1] |= codeword_unpacked[j + 8 * (VEC_N1_SIZE_BYTES - 1)] << j; | |||
} | |||
} | |||
/** | |||
* @brief Encodes a message message of PARAM_K bits to a BCH codeword codeword of PARAM_N1 bits | |||
* | |||
* Following @cite lin1983error (Chapter 4 - Cyclic Codes), | |||
* We perform a systematic encoding using a linear (PARAM_N1 - PARAM_K)-stage shift register | |||
* with feedback connections based on the generator polynomial bch_poly of the BCH code. | |||
* | |||
* @param[out] codeword Array of size VEC_N1_SIZE_BYTES receiving the encoded message | |||
* @param[in] message Array of size VEC_K_SIZE_BYTES storing the message | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_bch_code_encode(uint8_t *codeword, const uint8_t *message) { | |||
uint8_t message_unpacked[PARAM_K]; | |||
uint8_t codeword_unpacked[PARAM_N1] = {0}; | |||
unpack_message(message_unpacked, message); | |||
lfsr_encode(codeword_unpacked, message_unpacked); | |||
pack_codeword(codeword, codeword_unpacked); | |||
} | |||
/** | |||
* @brief Computes the error locator polynomial (ELP) sigma | |||
* | |||
* This is a constant time implementation of Berlekamp's simplified algorithm (see @cite joiner1995decoding). <br> | |||
* We use the letter p for rho which is initialized at -1/2. <br> | |||
* The array X_sigma_p represents the polynomial X^(2(mu-rho))*sigma_p(X). <br> | |||
* Instead of maintaining a list of sigmas, we update in place both sigma and X_sigma_p. <br> | |||
* sigma_copy serves as a temporary save of sigma in case X_sigma_p needs to be updated. <br> | |||
* We can properly correct only if the degree of sigma does not exceed PARAM_DELTA. | |||
* This means only the first PARAM_DELTA + 1 coefficients of sigma are of value | |||
* and we only need to save its first PARAM_DELTA - 1 coefficients. | |||
* | |||
* @returns the degree of the ELP sigma | |||
* @param[out] sigma Array of size (at least) PARAM_DELTA receiving the ELP | |||
* @param[in] syndromes Array of size (at least) 2*PARAM_DELTA storing the syndromes | |||
*/ | |||
static size_t compute_elp(uint16_t *sigma, const uint16_t *syndromes) { | |||
sigma[0] = 1; | |||
size_t deg_sigma = 0; | |||
size_t deg_sigma_p = 0; | |||
uint16_t sigma_copy[PARAM_DELTA - 1] = {0}; | |||
size_t deg_sigma_copy = 0; | |||
uint16_t X_sigma_p[PARAM_DELTA + 1] = {0, 1}; | |||
int32_t pp = -1; // 2*rho | |||
uint16_t d_p = 1; | |||
uint16_t d = syndromes[0]; | |||
for (size_t mu = 0; mu < PARAM_DELTA; ++mu) { | |||
// Save sigma in case we need it to update X_sigma_p | |||
memcpy(sigma_copy, sigma, 2 * (PARAM_DELTA - 1)); | |||
deg_sigma_copy = deg_sigma; | |||
uint16_t dd = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(d, PQCLEAN_HQC1921CCA2_LEAKTIME_gf_inverse(d_p)); // 0 if(d == 0) | |||
for (size_t i = 1; (i <= 2 * mu + 1) && (i <= PARAM_DELTA); ++i) { | |||
sigma[i] ^= PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(dd, X_sigma_p[i]); | |||
} | |||
size_t deg_X = 2 * mu - pp; // 2*(mu-rho) | |||
size_t deg_X_sigma_p = deg_X + deg_sigma_p; | |||
// mask1 = 0xffff if(d != 0) and 0 otherwise | |||
int16_t mask1 = -((uint16_t) - d >> 15); | |||
// mask2 = 0xffff if(deg_X_sigma_p > deg_sigma) and 0 otherwise | |||
int16_t mask2 = -((uint16_t) (deg_sigma - deg_X_sigma_p) >> 15); | |||
// mask12 = 0xffff if the deg_sigma increased and 0 otherwise | |||
int16_t mask12 = mask1 & mask2; | |||
deg_sigma = (mask12 & deg_X_sigma_p) ^ (~mask12 & deg_sigma); | |||
if (mu == PARAM_DELTA - 1) { | |||
break; | |||
} | |||
// Update pp, d_p and X_sigma_p if needed | |||
pp = (mask12 & (2 * mu)) ^ (~mask12 & pp); | |||
d_p = (mask12 & d) ^ (~mask12 & d_p); | |||
for (size_t i = PARAM_DELTA - 1; i; --i) { | |||
X_sigma_p[i + 1] = (mask12 & sigma_copy[i - 1]) ^ (~mask12 & X_sigma_p[i - 1]); | |||
} | |||
X_sigma_p[1] = 0; | |||
X_sigma_p[0] = 0; | |||
deg_sigma_p = (mask12 & deg_sigma_copy) ^ (~mask12 & deg_sigma_p); | |||
// Compute the next discrepancy | |||
d = syndromes[2 * mu + 2]; | |||
for (size_t i = 1; (i <= 2 * mu + 1) && (i <= PARAM_DELTA); ++i) { | |||
d ^= PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(sigma[i], syndromes[2 * mu + 2 - i]); | |||
} | |||
} | |||
return deg_sigma; | |||
} | |||
/** | |||
* @brief Retrieves the message message from the codeword codeword | |||
* | |||
* Since we performed a systematic encoding, the message is the last PARAM_K bits of the codeword. | |||
* | |||
* @param[out] message Array of size VEC_K_SIZE_BYTES receiving the message | |||
* @param[in] codeword Array of size VEC_N1_SIZE_BYTES storing the codeword | |||
*/ | |||
static void message_from_codeword(uint8_t *message, const uint8_t *codeword) { | |||
int32_t val = PARAM_N1 - PARAM_K; | |||
uint8_t mask1 = 0xff << val % 8; | |||
uint8_t mask2 = 0xff >> (8 - val % 8); | |||
size_t index = val / 8; | |||
for (size_t i = 0; i < VEC_K_SIZE_BYTES - 1; ++i) { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
uint8_t message2 = (codeword[++index] & mask2) << (8 - val % 8); | |||
message[i] = message1 | message2; | |||
} | |||
// Last byte (8-val % 8 is the number of bits given by message1) | |||
if ((PARAM_K % 8 == 0) || (8 - val % 8 < PARAM_K % 8)) { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
uint8_t message2 = (codeword[++index] & mask2) << (8 - val % 8); | |||
message[VEC_K_SIZE_BYTES - 1] = message1 | message2; | |||
} else { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
message[VEC_K_SIZE_BYTES - 1] = message1; | |||
} | |||
} | |||
/** | |||
* @brief Computes the 2^PARAM_DELTA syndromes from the received vector vector | |||
* | |||
* Syndromes are the sum of powers of alpha weighted by vector's coefficients. | |||
* To do so, we use the additive FFT transpose, which takes as input a family w of GF(2^PARAM_M) elements | |||
* and outputs the weighted power sums of these w. <br> | |||
* Therefore, this requires twisting and applying a permutation before feeding vector to the fft transpose. <br> | |||
* For more details see Berstein, Chou and Schawbe's explanations: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] syndromes Array of size 2^(PARAM_FFT_T) receiving the 2*PARAM_DELTA syndromes | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES storing the received word | |||
*/ | |||
static void compute_syndromes(uint16_t *syndromes, const uint8_t *vector) { | |||
uint16_t w[1 << PARAM_M]; | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(w, vector); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_fft_t(syndromes, w, 2 * PARAM_DELTA); | |||
} | |||
/** | |||
* @brief Computes the error polynomial error from the error locator polynomial sigma | |||
* | |||
* See function fft for more details. | |||
* | |||
* @param[out] err Array of VEC_N1_SIZE_BYTES elements receiving the error polynomial | |||
* @param[in] sigma Array of 2^PARAM_FFT elements storing the error locator polynomial | |||
*/ | |||
static void compute_roots(uint8_t *error, const uint16_t *sigma) { | |||
uint16_t w[1 << PARAM_M] = {0}; // w will receive the evaluation of sigma in all field elements | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_fft(w, sigma, PARAM_DELTA + 1); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_fft_retrieve_bch_error_poly(error, w); | |||
} | |||
/** | |||
* @brief Decodes the received word | |||
* | |||
* This function relies on four steps: | |||
* <ol> | |||
* <li> The first step, done by additive FFT transpose, is the computation of the 2*PARAM_DELTA syndromes. | |||
* <li> The second step is the computation of the error-locator polynomial sigma. | |||
* <li> The third step, done by additive FFT, is finding the error-locator numbers by calculating the roots of the polynomial sigma and takings their inverses. | |||
* <li> The fourth step is the correction of the errors in the received polynomial. | |||
* </ol> | |||
* For a more complete picture on BCH decoding, see Shu. Lin and Daniel J. Costello in Error Control Coding: Fundamentals and Applications @cite lin1983error | |||
* | |||
* @param[out] message Array of size VEC_K_SIZE_BYTES receiving the decoded message | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES storing the received word | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_bch_code_decode(uint8_t *message, uint8_t *vector) { | |||
uint16_t syndromes[1 << PARAM_FFT_T]; | |||
uint16_t sigma[1 << PARAM_FFT] = {0}; | |||
uint8_t error[(1 << PARAM_M) / 8] = {0}; | |||
// Calculate the 2*PARAM_DELTA syndromes | |||
compute_syndromes(syndromes, vector); | |||
// Compute the error locator polynomial sigma | |||
// Sigma's degree is at most PARAM_DELTA but the FFT requires the extra room | |||
compute_elp(sigma, syndromes); | |||
// Compute the error polynomial error | |||
compute_roots(error, sigma); | |||
// Add the error polynomial to the received polynomial | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_add(vector, vector, error, VEC_N1_SIZE_BYTES); | |||
// Retrieve the message from the decoded codeword | |||
message_from_codeword(message, vector); | |||
} |
@@ -1,16 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1921CCA2_LEAKTIME_BCH_H | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_BCH_H | |||
/** | |||
* @file bch.h | |||
* Header file of bch.c | |||
*/ | |||
#include "parameters.h" | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_bch_code_encode(uint8_t *codeword, const uint8_t *message); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_bch_code_decode(uint8_t *message, uint8_t *vector); | |||
#endif |
@@ -1,628 +0,0 @@ | |||
/** | |||
* @file fft.c | |||
* Implementation of the additive FFT and its transpose. | |||
* This implementation is based on the paper from Gao and Mateer: <br> | |||
* Shuhong Gao and Todd Mateer, Additive Fast Fourier Transforms over Finite Fields, | |||
* IEEE Transactions on Information Theory 56 (2010), 6265--6272. | |||
* http://www.math.clemson.edu/~sgao/papers/GM10.pdf <br> | |||
* and includes improvements proposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
*/ | |||
#include "fft.h" | |||
#include "gf.h" | |||
#include "parameters.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
static void compute_fft_betas(uint16_t *betas); | |||
static void compute_subset_sums(uint16_t *subset_sums, const uint16_t *set, size_t set_size); | |||
static void radix_t(uint16_t *f, const uint16_t *f0, const uint16_t *f1, uint32_t m_f); | |||
static void fft_t_rec(uint16_t *f, const uint16_t *w, size_t f_coeffs, uint8_t m, uint32_t m_f, const uint16_t *betas); | |||
static void radix(uint16_t *f0, uint16_t *f1, const uint16_t *f, uint32_t m_f); | |||
static void fft_rec(uint16_t *w, uint16_t *f, size_t f_coeffs, uint8_t m, uint32_t m_f, const uint16_t *betas); | |||
/** | |||
* @brief Computes the basis of betas (omitting 1) used in the additive FFT and its transpose | |||
* | |||
* @param[out] betas Array of size PARAM_M-1 | |||
*/ | |||
static void compute_fft_betas(uint16_t *betas) { | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
betas[i] = 1 << (PARAM_M - 1 - i); | |||
} | |||
} | |||
/** | |||
* @brief Computes the subset sums of the given set | |||
* | |||
* The array subset_sums is such that its ith element is | |||
* the subset sum of the set elements given by the binary form of i. | |||
* | |||
* @param[out] subset_sums Array of size 2^set_size receiving the subset sums | |||
* @param[in] set Array of set_size elements | |||
* @param[in] set_size Size of the array set | |||
*/ | |||
static void compute_subset_sums(uint16_t *subset_sums, const uint16_t *set, size_t set_size) { | |||
subset_sums[0] = 0; | |||
for (size_t i = 0; i < set_size; ++i) { | |||
for (size_t j = 0; j < (((size_t)1) << i); ++j) { | |||
subset_sums[(((size_t)1) << i) + j] = set[i] ^ subset_sums[j]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Transpose of the linear radix conversion | |||
* | |||
* This is a direct transposition of the radix function | |||
* implemented following the process of transposing a linear function as exposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f Array of size a power of 2 | |||
* @param[in] f0 Array half the size of f | |||
* @param[in] f1 Array half the size of f | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the number of coefficients of f | |||
*/ | |||
static void radix_t(uint16_t *f, const uint16_t *f0, const uint16_t *f1, uint32_t m_f) { | |||
switch (m_f) { | |||
case 4: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
f[4] = f[2] ^ f0[2]; | |||
f[5] = f[3] ^ f1[2]; | |||
f[6] = f[4] ^ f0[3] ^ f1[2]; | |||
f[7] = f[3] ^ f0[3] ^ f1[3]; | |||
f[8] = f[4] ^ f0[4]; | |||
f[9] = f[5] ^ f1[4]; | |||
f[10] = f[6] ^ f0[5] ^ f1[4]; | |||
f[11] = f[7] ^ f0[5] ^ f1[4] ^ f1[5]; | |||
f[12] = f[8] ^ f0[5] ^ f0[6] ^ f1[4]; | |||
f[13] = f[7] ^ f[9] ^ f[11] ^ f1[6]; | |||
f[14] = f[6] ^ f0[6] ^ f0[7] ^ f1[6]; | |||
f[15] = f[7] ^ f0[7] ^ f1[7]; | |||
return; | |||
case 3: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
f[4] = f[2] ^ f0[2]; | |||
f[5] = f[3] ^ f1[2]; | |||
f[6] = f[4] ^ f0[3] ^ f1[2]; | |||
f[7] = f[3] ^ f0[3] ^ f1[3]; | |||
return; | |||
case 2: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
return; | |||
case 1: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
return; | |||
default: | |||
; | |||
size_t n = ((size_t)1) << (m_f - 2); | |||
uint16_t Q0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t Q1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t Q[1 << 2 * (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R[1 << 2 * (PARAM_FFT_T - 2)] = {0}; | |||
memcpy(Q0, f0 + n, 2 * n); | |||
memcpy(Q1, f1 + n, 2 * n); | |||
memcpy(R0, f0, 2 * n); | |||
memcpy(R1, f1, 2 * n); | |||
radix_t (Q, Q0, Q1, m_f - 1); | |||
radix_t (R, R0, R1, m_f - 1); | |||
memcpy(f, R, 4 * n); | |||
memcpy(f + 2 * n, R + n, 2 * n); | |||
memcpy(f + 3 * n, Q + n, 2 * n); | |||
for (size_t i = 0; i < n; ++i) { | |||
f[2 * n + i] ^= Q[i]; | |||
f[3 * n + i] ^= f[2 * n + i]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Recursively computes syndromes of family w | |||
* | |||
* This function is a subroutine of the function fft_t | |||
* | |||
* @param[out] f Array receiving the syndromes | |||
* @param[in] w Array storing the family | |||
* @param[in] f_coeffs Length of syndromes vector | |||
* @param[in] m 2^m is the smallest power of 2 greater or equal to the length of family w | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the length of f | |||
* @param[in] betas FFT constants | |||
*/ | |||
static void fft_t_rec(uint16_t *f, const uint16_t *w, size_t f_coeffs, | |||
uint8_t m, uint32_t m_f, const uint16_t *betas) { | |||
size_t k = ((size_t)1) << (m - 1); | |||
uint16_t gammas[PARAM_M - 2] = {0}; | |||
uint16_t deltas[PARAM_M - 2] = {0}; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
uint16_t u[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t f0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)] = {0}; | |||
// Step 1 | |||
if (m_f == 1) { | |||
for (size_t i = 0; i < (((size_t)1) << m); ++i) { | |||
f[0] ^= w[i]; | |||
} | |||
for (size_t j = 0; j < m; ++j) { | |||
for (size_t ki = 0; ki < (((size_t)1) << j); ++ki) { | |||
size_t index = (((size_t)1) << j) + ki; | |||
betas_sums[index] = betas_sums[ki] ^ betas[j]; | |||
f[1] ^= PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(betas_sums[index], w[index]); | |||
} | |||
} | |||
return; | |||
} | |||
// Compute gammas and deltas | |||
for (uint8_t i = 0; i < m - 1; ++i) { | |||
gammas[i] = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(betas[i], PQCLEAN_HQC1921CCA2_LEAKTIME_gf_inverse(betas[m - 1])); | |||
deltas[i] = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_square(gammas[i]) ^ gammas[i]; | |||
} | |||
// Compute gammas subset sums | |||
compute_subset_sums(gammas_sums, gammas, m - 1); | |||
/* Step 6: Compute u and v from w (aka w) | |||
* w[i] = u[i] + G[i].v[i] | |||
* w[k+i] = w[i] + v[i] = u[i] + (G[i]+1).v[i] | |||
* Transpose: | |||
* u[i] = w[i] + w[k+i] | |||
* v[i] = G[i].w[i] + (G[i]+1).w[k+i] = G[i].u[i] + w[k+i] */ | |||
if (f_coeffs <= 3) { // 3-coefficient polynomial f case | |||
// Step 5: Compute f0 from u and f1 from v | |||
f1[1] = 0; | |||
u[0] = w[0] ^ w[k]; | |||
f1[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
f1[0] ^= PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(gammas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
} else { | |||
uint16_t v[1 << (PARAM_M - 2)] = {0}; | |||
u[0] = w[0] ^ w[k]; | |||
v[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
v[i] = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(gammas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
// Step 5: Compute f0 from u and f1 from v | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
fft_t_rec(f1, v, f_coeffs / 2, m - 1, m_f - 1, deltas); | |||
} | |||
// Step 3: Compute g from g0 and g1 | |||
radix_t(f, f0, f1, m_f); | |||
// Step 2: compute f from g | |||
if (betas[m - 1] != 1) { | |||
uint16_t beta_m_pow = 1; | |||
for (size_t i = 1; i < (((size_t)1) << m_f); ++i) { | |||
beta_m_pow = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(beta_m_pow, betas[m - 1]); | |||
f[i] = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(beta_m_pow, f[i]); | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Computes the syndromes f of the family w | |||
* | |||
* Since the syndromes linear map is the transpose of multipoint evaluation, | |||
* it uses exactly the same constants, either hardcoded or precomputed by compute_fft_lut(...). <br> | |||
* This follows directives from Bernstein, Chou and Schwabe given here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f Array of size 2*(PARAM_FFT_T) elements receiving the syndromes | |||
* @param[in] w Array of PARAM_GF_MUL_ORDER+1 elements | |||
* @param[in] f_coeffs Length of syndromes vector f | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_fft_t(uint16_t *f, const uint16_t *w, size_t f_coeffs) { | |||
// Transposed from Gao and Mateer algorithm | |||
uint16_t betas[PARAM_M - 1]; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
uint16_t u[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t deltas[PARAM_M - 1]; | |||
uint16_t f0[1 << (PARAM_FFT_T - 1)]; | |||
uint16_t f1[1 << (PARAM_FFT_T - 1)]; | |||
compute_fft_betas(betas); | |||
compute_subset_sums(betas_sums, betas, PARAM_M - 1); | |||
/* Step 6: Compute u and v from w (aka w) | |||
* | |||
* We had: | |||
* w[i] = u[i] + G[i].v[i] | |||
* w[k+i] = w[i] + v[i] = u[i] + (G[i]+1).v[i] | |||
* Transpose: | |||
* u[i] = w[i] + w[k+i] | |||
* v[i] = G[i].w[i] + (G[i]+1).w[k+i] = G[i].u[i] + w[k+i] */ | |||
u[0] = w[0] ^ w[k]; | |||
v[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
v[i] = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(betas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
// Compute deltas | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
deltas[i] = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_square(betas[i]) ^ betas[i]; | |||
} | |||
// Step 5: Compute f0 from u and f1 from v | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, PARAM_M - 1, PARAM_FFT_T - 1, deltas); | |||
fft_t_rec(f1, v, f_coeffs / 2, PARAM_M - 1, PARAM_FFT_T - 1, deltas); | |||
// Step 3: Compute g from g0 and g1 | |||
radix_t(f, f0, f1, PARAM_FFT_T); | |||
// Step 2: beta_m = 1 so f = g | |||
} | |||
/** | |||
* @brief Computes the radix conversion of a polynomial f in GF(2^m)[x] | |||
* | |||
* Computes f0 and f1 such that f(x) = f0(x^2-x) + x.f1(x^2-x) | |||
* as proposed by Bernstein, Chou and Schwabe: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f0 Array half the size of f | |||
* @param[out] f1 Array half the size of f | |||
* @param[in] f Array of size a power of 2 | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the number of coefficients of f | |||
*/ | |||
static void radix(uint16_t *f0, uint16_t *f1, const uint16_t *f, uint32_t m_f) { | |||
switch (m_f) { | |||
case 4: | |||
f0[4] = f[8] ^ f[12]; | |||
f0[6] = f[12] ^ f[14]; | |||
f0[7] = f[14] ^ f[15]; | |||
f1[5] = f[11] ^ f[13]; | |||
f1[6] = f[13] ^ f[14]; | |||
f1[7] = f[15]; | |||
f0[5] = f[10] ^ f[12] ^ f1[5]; | |||
f1[4] = f[9] ^ f[13] ^ f0[5]; | |||
f0[0] = f[0]; | |||
f1[3] = f[7] ^ f[11] ^ f[15]; | |||
f0[3] = f[6] ^ f[10] ^ f[14] ^ f1[3]; | |||
f0[2] = f[4] ^ f0[4] ^ f0[3] ^ f1[3]; | |||
f1[1] = f[3] ^ f[5] ^ f[9] ^ f[13] ^ f1[3]; | |||
f1[2] = f[3] ^ f1[1] ^ f0[3]; | |||
f0[1] = f[2] ^ f0[2] ^ f1[1]; | |||
f1[0] = f[1] ^ f0[1]; | |||
return; | |||
case 3: | |||
f0[0] = f[0]; | |||
f0[2] = f[4] ^ f[6]; | |||
f0[3] = f[6] ^ f[7]; | |||
f1[1] = f[3] ^ f[5] ^ f[7]; | |||
f1[2] = f[5] ^ f[6]; | |||
f1[3] = f[7]; | |||
f0[1] = f[2] ^ f0[2] ^ f1[1]; | |||
f1[0] = f[1] ^ f0[1]; | |||
return; | |||
case 2: | |||
f0[0] = f[0]; | |||
f0[1] = f[2] ^ f[3]; | |||
f1[0] = f[1] ^ f0[1]; | |||
f1[1] = f[3]; | |||
return; | |||
case 1: | |||
f0[0] = f[0]; | |||
f1[0] = f[1]; | |||
return; | |||
default: | |||
; | |||
size_t n = ((size_t)1) << (m_f - 2); | |||
uint16_t Q[2 * (1 << (PARAM_FFT - 2))]; | |||
uint16_t R[2 * (1 << (PARAM_FFT - 2))]; | |||
uint16_t Q0[1 << (PARAM_FFT - 2)]; | |||
uint16_t Q1[1 << (PARAM_FFT - 2)]; | |||
uint16_t R0[1 << (PARAM_FFT - 2)]; | |||
uint16_t R1[1 << (PARAM_FFT - 2)]; | |||
memcpy(Q, f + 3 * n, 2 * n); | |||
memcpy(Q + n, f + 3 * n, 2 * n); | |||
memcpy(R, f, 4 * n); | |||
for (size_t i = 0; i < n; ++i) { | |||
Q[i] ^= f[2 * n + i]; | |||
R[n + i] ^= Q[i]; | |||
} | |||
radix(Q0, Q1, Q, m_f - 1); | |||
radix(R0, R1, R, m_f - 1); | |||
memcpy(f0, R0, 2 * n); | |||
memcpy(f0 + n, Q0, 2 * n); | |||
memcpy(f1, R1, 2 * n); | |||
memcpy(f1 + n, Q1, 2 * n); | |||
} | |||
} | |||
/** | |||
* @brief Evaluates f at all subset sums of a given set | |||
* | |||
* This function is a subroutine of the function fft. | |||
* | |||
* @param[out] w Array | |||
* @param[in] f Array | |||
* @param[in] f_coeffs Number of coefficients of f | |||
* @param[in] m Number of betas | |||
* @param[in] m_f Number of coefficients of f (one more than its degree) | |||
* @param[in] betas FFT constants | |||
*/ | |||
static void fft_rec(uint16_t *w, uint16_t *f, size_t f_coeffs, | |||
uint8_t m, uint32_t m_f, const uint16_t *betas) { | |||
uint16_t f0[1 << (PARAM_FFT - 2)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT - 2)] = {0}; | |||
uint16_t gammas[PARAM_M - 2] = {0}; | |||
uint16_t deltas[PARAM_M - 2] = {0}; | |||
size_t k = ((size_t)1) << (m - 1); | |||
uint16_t gammas_sums[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t u[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 2)] = {0}; | |||
// Step 1 | |||
if (m_f == 1) { | |||
uint16_t tmp[PARAM_M - (PARAM_FFT - 1)]; | |||
for (size_t i = 0; i < m; ++i) { | |||
tmp[i] = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(betas[i], f[1]); | |||
} | |||
w[0] = f[0]; | |||
for (size_t j = 0; j < m; ++j) { | |||
for (size_t ki = 0; ki < (((size_t)1) << j); ++ki) { | |||
w[(((size_t)1) << j) + ki] = w[ki] ^ tmp[j]; | |||
} | |||
} | |||
return; | |||
} | |||
// Step 2: compute g | |||
if (betas[m - 1] != 1) { | |||
uint16_t beta_m_pow = 1; | |||
for (size_t i = 1; i < (((size_t)1) << m_f); ++i) { | |||
beta_m_pow = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(beta_m_pow, betas[m - 1]); | |||
f[i] = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(beta_m_pow, f[i]); | |||
} | |||
} | |||
// Step 3 | |||
radix(f0, f1, f, m_f); | |||
// Step 4: compute gammas and deltas | |||
for (uint8_t i = 0; i < m - 1; ++i) { | |||
gammas[i] = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(betas[i], PQCLEAN_HQC1921CCA2_LEAKTIME_gf_inverse(betas[m - 1])); | |||
deltas[i] = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_square(gammas[i]) ^ gammas[i]; | |||
} | |||
// Compute gammas sums | |||
compute_subset_sums(gammas_sums, gammas, m - 1); | |||
// Step 5 | |||
fft_rec(u, f0, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
if (f_coeffs <= 3) { // 3-coefficient polynomial f case: f1 is constant | |||
w[0] = u[0]; | |||
w[k] = u[0] ^ f1[0]; | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(gammas_sums[i], f1[0]); | |||
w[k + i] = w[i] ^ f1[0]; | |||
} | |||
} else { | |||
fft_rec(v, f1, f_coeffs / 2, m - 1, m_f - 1, deltas); | |||
// Step 6 | |||
memcpy(w + k, v, 2 * k); | |||
w[0] = u[0]; | |||
w[k] ^= u[0]; | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(gammas_sums[i], v[i]); | |||
w[k + i] ^= w[i]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Evaluates f on all fields elements using an additive FFT algorithm | |||
* | |||
* f_coeffs is the number of coefficients of f (one less than its degree). <br> | |||
* The FFT proceeds recursively to evaluate f at all subset sums of a basis B. <br> | |||
* This implementation is based on the paper from Gao and Mateer: <br> | |||
* Shuhong Gao and Todd Mateer, Additive Fast Fourier Transforms over Finite Fields, | |||
* IEEE Transactions on Information Theory 56 (2010), 6265--6272. | |||
* http://www.math.clemson.edu/~sgao/papers/GM10.pdf <br> | |||
* and includes improvements proposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf <br> | |||
* Constants betas, gammas and deltas involved in the algorithm are either hardcoded or precomputed | |||
* by the subroutine compute_fft_lut(...). <br> | |||
* Note that on this first call (as opposed to the recursive calls to fft_rec), gammas are equal to betas, | |||
* meaning the first gammas subset sums are actually the subset sums of betas (except 1). <br> | |||
* Also note that f is altered during computation (twisted at each level). | |||
* | |||
* @param[out] w Array | |||
* @param[in] f Array of 2^PARAM_FFT elements | |||
* @param[in] f_coeffs Number coefficients of f (i.e. deg(f)+1) | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_fft(uint16_t *w, const uint16_t *f, size_t f_coeffs) { | |||
uint16_t betas[PARAM_M - 1] = {0}; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t f0[1 << (PARAM_FFT - 1)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT - 1)] = {0}; | |||
uint16_t deltas[PARAM_M - 1]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
uint16_t u[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 1)] = {0}; | |||
// Follows Gao and Mateer algorithm | |||
compute_fft_betas(betas); | |||
// Step 1: PARAM_FFT > 1, nothing to do | |||
// Compute gammas sums | |||
compute_subset_sums(betas_sums, betas, PARAM_M - 1); | |||
// Step 2: beta_m = 1, nothing to do | |||
// Step 3 | |||
radix(f0, f1, f, PARAM_FFT); | |||
// Step 4: Compute deltas | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
deltas[i] = PQCLEAN_HQC1921CCA2_LEAKTIME_gf_square(betas[i]) ^ betas[i]; | |||
} | |||
// Step 5 | |||
fft_rec(u, f0, (f_coeffs + 1) / 2, PARAM_M - 1, PARAM_FFT - 1, deltas); | |||
fft_rec(v, f1, f_coeffs / 2, PARAM_M - 1, PARAM_FFT - 1, deltas); | |||
// Step 6, 7 and error polynomial computation | |||
memcpy(w + k, v, 2 * k); | |||
// Check if 0 is root | |||
w[0] = u[0]; | |||
// Check if 1 is root | |||
w[k] ^= u[0]; | |||
// Find other roots | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(betas_sums[i], v[i]); | |||
w[k + i] ^= w[i]; | |||
} | |||
} | |||
/** | |||
* @brief Arranges the received word vector in a form w such that applying the additive FFT transpose to w yields the BCH syndromes of the received word vector. | |||
* | |||
* Since the received word vector gives coefficients of the primitive element alpha, we twist accordingly. <br> | |||
* Furthermore, the additive FFT transpose needs elements indexed by their decomposition on the chosen basis, | |||
* so we apply the adequate permutation. | |||
* | |||
* @param[out] w Array of size 2^PARAM_M | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(uint16_t *w, const uint8_t *vector) { | |||
uint16_t r[1 << PARAM_M]; | |||
uint16_t gammas[PARAM_M - 1]; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
// Unpack the received word vector into array r | |||
size_t i; | |||
for (i = 0; i < VEC_N1_SIZE_BYTES - (PARAM_N1 % 8 != 0); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
r[8 * i + j] = (vector[i] >> j) & 1; | |||
} | |||
} | |||
// Last byte | |||
for (size_t j = 0; j < PARAM_N1 % 8; ++j) { | |||
r[8 * i + j] = (vector[i] >> j) & 1; | |||
} | |||
// Complete r with zeros | |||
memset(r + PARAM_N1, 0, 2 * ((1 << PARAM_M) - PARAM_N1)); | |||
compute_fft_betas(gammas); | |||
compute_subset_sums(gammas_sums, gammas, PARAM_M - 1); | |||
// Twist and permute r adequately to obtain w | |||
w[0] = 0; | |||
w[k] = -r[0] & 1; | |||
for (i = 1; i < k; ++i) { | |||
w[i] = -r[PQCLEAN_HQC1921CCA2_LEAKTIME_gf_log(gammas_sums[i])] & gammas_sums[i]; | |||
w[k + i] = -r[PQCLEAN_HQC1921CCA2_LEAKTIME_gf_log(gammas_sums[i] ^ 1)] & (gammas_sums[i] ^ 1); | |||
} | |||
} | |||
/** | |||
* @brief Retrieves the error polynomial error from the evaluations w of the ELP (Error Locator Polynomial) on all field elements. | |||
* | |||
* @param[out] error Array of size VEC_N1_SIZE_BYTES | |||
* @param[in] w Array of size 2^PARAM_M | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_fft_retrieve_bch_error_poly(uint8_t *error, const uint16_t *w) { | |||
uint16_t gammas[PARAM_M - 1]; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
size_t index = PARAM_GF_MUL_ORDER; | |||
compute_fft_betas(gammas); | |||
compute_subset_sums(gammas_sums, gammas, PARAM_M - 1); | |||
error[0] ^= 1 ^ ((uint16_t) - w[0] >> 15); | |||
uint8_t bit = 1 ^ ((uint16_t) - w[k] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
for (size_t i = 1; i < k; ++i) { | |||
index = PARAM_GF_MUL_ORDER - PQCLEAN_HQC1921CCA2_LEAKTIME_gf_log(gammas_sums[i]); | |||
bit = 1 ^ ((uint16_t) - w[i] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
index = PARAM_GF_MUL_ORDER - PQCLEAN_HQC1921CCA2_LEAKTIME_gf_log(gammas_sums[i] ^ 1); | |||
bit = 1 ^ ((uint16_t) - w[k + i] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
} | |||
} |
@@ -1,18 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1921CCA2_LEAKTIME_FFT_H | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_FFT_H | |||
/** | |||
* @file fft.h | |||
* Header file of fft.c | |||
*/ | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_fft_t(uint16_t *f, const uint16_t *w, size_t f_coeffs); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(uint16_t *w, const uint8_t *vector); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_fft(uint16_t *w, const uint16_t *f, size_t f_coeffs); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_fft_retrieve_bch_error_poly(uint8_t *error, const uint16_t *w); | |||
#endif |
@@ -1,18 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1921CCA2_LEAKTIME_GF_H | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_GF_H | |||
/** | |||
* @file gf.h | |||
* Header file of gf.c | |||
*/ | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
uint16_t PQCLEAN_HQC1921CCA2_LEAKTIME_gf_log(uint16_t elt); | |||
uint16_t PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mul(uint16_t a, uint16_t b); | |||
uint16_t PQCLEAN_HQC1921CCA2_LEAKTIME_gf_square(uint16_t a); | |||
uint16_t PQCLEAN_HQC1921CCA2_LEAKTIME_gf_inverse(uint16_t a); | |||
uint16_t PQCLEAN_HQC1921CCA2_LEAKTIME_gf_mod(uint16_t i); | |||
#endif |
@@ -1,123 +0,0 @@ | |||
/** | |||
* \file gf2x.c | |||
* \brief Implementation of multiplication of two polynomials | |||
*/ | |||
#include "gf2x.h" | |||
#include "parameters.h" | |||
#include "util.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
#define WORD_TYPE uint64_t | |||
#define WORD_TYPE_BITS (sizeof(WORD_TYPE) * 8) | |||
#define UTILS_VECTOR_ARRAY_SIZE CEIL_DIVIDE(PARAM_N, WORD_TYPE_BITS) | |||
static int vect_mul_precompute_rows(WORD_TYPE *o, const WORD_TYPE *v); | |||
/** | |||
* @brief A subroutine used in the function sparse_dense_mul() | |||
* | |||
* @param[out] o Pointer to an array | |||
* @param[in] v Pointer to an array | |||
* @return 0 if precomputation is successful, -1 otherwise | |||
*/ | |||
static int vect_mul_precompute_rows(WORD_TYPE *o, const WORD_TYPE *v) { | |||
int8_t var; | |||
for (size_t i = 0; i < PARAM_N; ++i) { | |||
var = 0; | |||
// All the bits that we need are in the same block | |||
if (((i % WORD_TYPE_BITS) == 0) && (i != PARAM_N - (PARAM_N % WORD_TYPE_BITS))) { | |||
var = 1; | |||
} | |||
// Cases where the bits are in before the last block, the last block and the first block | |||
if (i > PARAM_N - WORD_TYPE_BITS) { | |||
if (i >= PARAM_N - (PARAM_N % WORD_TYPE_BITS)) { | |||
var = 2; | |||
} else { | |||
var = 3; | |||
} | |||
} | |||
switch (var) { | |||
case 0: | |||
// Take bits in the last block and the first one | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[(i / WORD_TYPE_BITS) + 1] << (WORD_TYPE_BITS - (i % WORD_TYPE_BITS)); | |||
break; | |||
case 1: | |||
o[i] = v[i / WORD_TYPE_BITS]; | |||
break; | |||
case 2: | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[0] << ((PARAM_N - i) % WORD_TYPE_BITS); | |||
break; | |||
case 3: | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[(i / WORD_TYPE_BITS) + 1] << (WORD_TYPE_BITS - (i % WORD_TYPE_BITS)); | |||
o[i] += v[0] << ((WORD_TYPE_BITS - i + (PARAM_N % WORD_TYPE_BITS)) % WORD_TYPE_BITS); | |||
break; | |||
default: | |||
return -1; | |||
} | |||
} | |||
return 0; | |||
} | |||
/** | |||
* @brief Multiplies two vectors | |||
* | |||
* This function multiplies two vectors: a sparse vector of Hamming weight equal to <b>weight</b> and a dense (random) vector. | |||
* The vector <b>a1</b> is the sparse vector and <b>a2</b> is the dense vector. | |||
* We notice that the idea is explained using vector of 32 bits elements instead of 64 (the algorithm works in booth cases). | |||
* | |||
* @param[out] o Pointer to a vector that is the result of the multiplication | |||
* @param[in] a1 Pointer to the sparse vector stored by position | |||
* @param[in] a2 Pointer to the dense vector | |||
* @param[in] weight Integer that is the weight of the sparse vector | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_mul(uint8_t *o, const uint32_t *a1, const uint8_t *a2, uint16_t weight) { | |||
WORD_TYPE v1[UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
WORD_TYPE res[UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
WORD_TYPE precomputation_array [PARAM_N] = {0}; | |||
WORD_TYPE row [UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
uint32_t index; | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_load8_arr(v1, UTILS_VECTOR_ARRAY_SIZE, a2, VEC_N_SIZE_BYTES); | |||
vect_mul_precompute_rows(precomputation_array, v1); | |||
for (size_t i = 0; i < weight; ++i) { | |||
int32_t k = UTILS_VECTOR_ARRAY_SIZE; | |||
for (size_t j = 0; j < UTILS_VECTOR_ARRAY_SIZE - 1; ++j) { | |||
index = WORD_TYPE_BITS * (uint32_t)j - a1[i]; | |||
if (index > PARAM_N) { | |||
index += PARAM_N; | |||
} | |||
row[j] = precomputation_array[index]; | |||
} | |||
index = WORD_TYPE_BITS * (UTILS_VECTOR_ARRAY_SIZE - 1) - a1[i]; | |||
row[UTILS_VECTOR_ARRAY_SIZE - 1] = precomputation_array[(index < PARAM_N ? index : index + PARAM_N)] & BITMASK(PARAM_N, WORD_TYPE_BITS); | |||
while (k--) { | |||
res[k] ^= row[k]; | |||
} | |||
} | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_store8_arr(o, VEC_N_SIZE_BYTES, res, UTILS_VECTOR_ARRAY_SIZE); | |||
} |
@@ -1,13 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1921CCA2_LEAKTIME_GF2X_H | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_GF2X_H | |||
/** | |||
* @file gf2x.h | |||
* @brief Header file for gf2x.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_mul(uint8_t *o, const uint32_t *a1, const uint8_t *a2, uint16_t weight); | |||
#endif |
@@ -1,135 +0,0 @@ | |||
/** | |||
* @file hqc.c | |||
* @brief Implementation of hqc.h | |||
*/ | |||
#include "gf2x.h" | |||
#include "hqc.h" | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "randombytes.h" | |||
#include "tensor.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
/** | |||
* @brief Keygen of the HQC_PKE IND_CPA scheme | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the <b>seed</b> used to generate the vector <b>h</b>. | |||
* | |||
* The secret key is composed of the <b>seed</b> used to generate vectors <b>x</b> and <b>y</b>. | |||
* As a technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[out] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_pke_keygen(uint8_t *pk, uint8_t *sk) { | |||
AES_XOF_struct sk_seedexpander; | |||
AES_XOF_struct pk_seedexpander; | |||
uint8_t sk_seed[SEED_BYTES] = {0}; | |||
uint8_t pk_seed[SEED_BYTES] = {0}; | |||
uint8_t x[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t y[PARAM_OMEGA] = {0}; | |||
uint8_t h[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t s[VEC_N_SIZE_BYTES] = {0}; | |||
// Create seed_expanders for public key and secret key | |||
randombytes(sk_seed, SEED_BYTES); | |||
seedexpander_init(&sk_seedexpander, sk_seed, sk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
randombytes(pk_seed, SEED_BYTES); | |||
seedexpander_init(&pk_seedexpander, pk_seed, pk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
// Compute secret key | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_fixed_weight(&sk_seedexpander, x, PARAM_OMEGA); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&sk_seedexpander, y, PARAM_OMEGA); | |||
// Compute public key | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random(&pk_seedexpander, h); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_mul(s, y, h, PARAM_OMEGA); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_add(s, x, s, VEC_N_SIZE_BYTES); | |||
// Parse keys to string | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_public_key_to_string(pk, pk_seed, s); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_secret_key_to_string(sk, sk_seed, pk); | |||
} | |||
/** | |||
* @brief Encryption of the HQC_PKE IND_CPA scheme | |||
* | |||
* The cihertext is composed of vectors <b>u</b> and <b>v</b>. | |||
* | |||
* @param[out] u Vector u (first part of the ciphertext) | |||
* @param[out] v Vector v (second part of the ciphertext) | |||
* @param[in] m Vector representing the message to encrypt | |||
* @param[in] theta Seed used to derive randomness required for encryption | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_pke_encrypt(uint8_t *u, uint8_t *v, const uint8_t *m, const uint8_t *theta, const uint8_t *pk) { | |||
AES_XOF_struct seedexpander; | |||
uint8_t h[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t s[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t r1[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t r2[PARAM_OMEGA_R] = {0}; | |||
uint8_t e[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp1[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp2[VEC_N_SIZE_BYTES] = {0}; | |||
// Create seed_expander from theta | |||
seedexpander_init(&seedexpander, theta, theta + 32, SEEDEXPANDER_MAX_LENGTH); | |||
// Retrieve h and s from public key | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_public_key_from_string(h, s, pk); | |||
// Generate r1, r2 and e | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_fixed_weight(&seedexpander, r1, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&seedexpander, r2, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_fixed_weight(&seedexpander, e, PARAM_OMEGA_E); | |||
// Compute u = r1 + r2.h | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_mul(u, r2, h, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_add(u, r1, u, VEC_N_SIZE_BYTES); | |||
// Compute v = m.G by encoding the message | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_tensor_code_encode(v, m); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_resize(tmp1, PARAM_N, v, PARAM_N1N2); | |||
// Compute v = m.G + s.r2 + e | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_mul(tmp2, r2, s, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_add(tmp2, e, tmp2, VEC_N_SIZE_BYTES); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_add(tmp2, tmp1, tmp2, VEC_N_SIZE_BYTES); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_resize(v, PARAM_N1N2, tmp2, PARAM_N); | |||
} | |||
/** | |||
* @brief Decryption of the HQC_PKE IND_CPA scheme | |||
* | |||
* @param[out] m Vector representing the decrypted message | |||
* @param[in] u Vector u (first part of the ciphertext) | |||
* @param[in] v Vector v (second part of the ciphertext) | |||
* @param[in] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_pke_decrypt(uint8_t *m, const uint8_t *u, const uint8_t *v, const uint8_t *sk) { | |||
uint8_t x[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t y[PARAM_OMEGA] = {0}; | |||
uint8_t pk[PUBLIC_KEY_BYTES] = {0}; | |||
uint8_t tmp1[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp2[VEC_N_SIZE_BYTES] = {0}; | |||
// Retrieve x, y, pk from secret key | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_secret_key_from_string(x, y, pk, sk); | |||
// Compute v - u.y | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_resize(tmp1, PARAM_N, v, PARAM_N1N2); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_mul(tmp2, y, u, PARAM_OMEGA); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_add(tmp2, tmp1, tmp2, VEC_N_SIZE_BYTES); | |||
// Compute m by decoding v - u.y | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_tensor_code_decode(m, tmp2); | |||
} |
@@ -1,15 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1921CCA2_LEAKTIME_HQC_H | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_HQC_H | |||
/** | |||
* @file hqc.h | |||
* @brief Functions of the HQC_PKE IND_CPA scheme | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_pke_keygen(uint8_t *pk, uint8_t *sk); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_pke_encrypt(uint8_t *u, uint8_t *v, const uint8_t *m, const uint8_t *theta, const uint8_t *pk); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_pke_decrypt(uint8_t *m, const uint8_t *u, const uint8_t *v, const uint8_t *sk); | |||
#endif |
@@ -1,154 +0,0 @@ | |||
/** | |||
* @file kem.c | |||
* @brief Implementation of api.h | |||
*/ | |||
#include "api.h" | |||
#include "hqc.h" | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "sha2.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
/** | |||
* @brief Keygen of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b>. | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As a technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[out] sk String containing the secret key | |||
* @returns 0 if keygen is successful | |||
*/ | |||
int PQCLEAN_HQC1921CCA2_LEAKTIME_crypto_kem_keypair(uint8_t *pk, uint8_t *sk) { | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_pke_keygen(pk, sk); | |||
return 0; | |||
} | |||
/** | |||
* @brief Encapsulation of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* @param[out] ct String containing the ciphertext | |||
* @param[out] ss String containing the shared secret | |||
* @param[in] pk String containing the public key | |||
* @returns 0 if encapsulation is successful | |||
*/ | |||
int PQCLEAN_HQC1921CCA2_LEAKTIME_crypto_kem_enc(uint8_t *ct, uint8_t *ss, const uint8_t *pk) { | |||
AES_XOF_struct G_seedexpander; | |||
uint8_t seed_G[VEC_K_SIZE_BYTES]; | |||
uint8_t diversifier_bytes[8] = {0}; | |||
uint8_t m[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t theta[SEED_BYTES] = {0}; | |||
uint8_t u[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d[SHA512_BYTES] = {0}; | |||
uint8_t mc[VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES] = {0}; | |||
// Computing m | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_from_randombytes(m); | |||
// Generating G function | |||
memcpy(seed_G, m, VEC_K_SIZE_BYTES); | |||
seedexpander_init(&G_seedexpander, seed_G, diversifier_bytes, SEEDEXPANDER_MAX_LENGTH); | |||
// Computing theta | |||
seedexpander(&G_seedexpander, theta, SEED_BYTES); | |||
// Encrypting m | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_pke_encrypt(u, v, m, theta, pk); | |||
// Computing d | |||
sha512(d, m, VEC_K_SIZE_BYTES); | |||
// Computing shared secret | |||
memcpy(mc, m, VEC_K_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES, u, VEC_N_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
sha512(ss, mc, VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES); | |||
// Computing ciphertext | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_ciphertext_to_string(ct, u, v, d); | |||
return 0; | |||
} | |||
/** | |||
* @brief Decapsulation of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* @param[out] ss String containing the shared secret | |||
* @param[in] ct String containing the cipĥertext | |||
* @param[in] sk String containing the secret key | |||
* @returns 0 if decapsulation is successful, -1 otherwise | |||
*/ | |||
int PQCLEAN_HQC1921CCA2_LEAKTIME_crypto_kem_dec(uint8_t *ss, const uint8_t *ct, const uint8_t *sk) { | |||
AES_XOF_struct G_seedexpander; | |||
uint8_t seed_G[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t diversifier_bytes[8] = {0}; | |||
uint8_t u[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d[SHA512_BYTES] = {0}; | |||
uint8_t pk[PUBLIC_KEY_BYTES] = {0}; | |||
uint8_t m[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t theta[SEED_BYTES] = {0}; | |||
uint8_t u2[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v2[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d2[SHA512_BYTES] = {0}; | |||
uint8_t mc[VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES] = {0}; | |||
int8_t abort = 0; | |||
// Retrieving u, v and d from ciphertext | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_ciphertext_from_string(u, v, d, ct); | |||
// Retrieving pk from sk | |||
memcpy(pk, sk + SEED_BYTES, PUBLIC_KEY_BYTES); | |||
// Decryting | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_pke_decrypt(m, u, v, sk); | |||
// Generating G function | |||
memcpy(seed_G, m, VEC_K_SIZE_BYTES); | |||
seedexpander_init(&G_seedexpander, seed_G, diversifier_bytes, SEEDEXPANDER_MAX_LENGTH); | |||
// Computing theta | |||
seedexpander(&G_seedexpander, theta, SEED_BYTES); | |||
// Encrypting m' | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_pke_encrypt(u2, v2, m, theta, pk); | |||
// Checking that c = c' and abort otherwise | |||
if (PQCLEAN_HQC1921CCA2_LEAKTIME_vect_compare(u, u2, VEC_N_SIZE_BYTES) != 0 || | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_compare(v, v2, VEC_N1N2_SIZE_BYTES) != 0) { | |||
abort = 1; | |||
} | |||
// Computing d' | |||
sha512(d2, m, VEC_K_SIZE_BYTES); | |||
// Checking that d = d' and abort otherwise | |||
if (memcmp(d, d2, SHA512_BYTES) != 0) { | |||
abort = 1; | |||
} | |||
if (abort == 1) { | |||
memset(ss, 0, SHARED_SECRET_BYTES); | |||
return -1; | |||
} | |||
// Computing shared secret | |||
memcpy(mc, m, VEC_K_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES, u, VEC_N_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
sha512(ss, mc, VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES); | |||
return 0; | |||
} |
@@ -1,109 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1921CCA2_LEAKTIME_HQC_PARAMETERS_H | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_HQC_PARAMETERS_H | |||
/** | |||
* @file parameters.h | |||
* @brief Parameters of the HQC_KEM IND-CCA2 scheme | |||
*/ | |||
#include "api.h" | |||
#define CEIL_DIVIDE(a, b) (((a)/(b)) + ((a) % (b) == 0 ? 0 : 1)) /*!< Divide a by b and ceil the result*/ | |||
#define BITMASK(a, size) ((1ULL << ((a) % (size))) - 1) /*!< Create a mask*/ | |||
/* | |||
#define PARAM_N Define the parameter n of the scheme | |||
#define PARAM_N1 Define the parameter n1 of the scheme (length of BCH code) | |||
#define PARAM_N2 Define the parameter n2 of the scheme (length of the repetition code) | |||
#define PARAM_N1N2 Define the parameter n1 * n2 of the scheme (length of the tensor code) | |||
#define PARAM_OMEGA Define the parameter omega of the scheme | |||
#define PARAM_OMEGA_E Define the parameter omega_e of the scheme | |||
#define PARAM_OMEGA_R Define the parameter omega_r of the scheme | |||
#define PARAM_SECURITY Define the security level corresponding to the chosen parameters | |||
#define PARAM_DFR_EXP Define the decryption failure rate corresponding to the chosen parameters | |||
#define SECRET_KEY_BYTES Define the size of the secret key in bytes | |||
#define PUBLIC_KEY_BYTES Define the size of the public key in bytes | |||
#define SHARED_SECRET_BYTES Define the size of the shared secret in bytes | |||
#define CIPHERTEXT_BYTES Define the size of the ciphertext in bytes | |||
#define UTILS_REJECTION_THRESHOLD Define the rejection threshold used to generate given weight vectors (see vector_set_random_fixed_weight function) | |||
#define VEC_N_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N sized vector in bytes | |||
#define VEC_N1_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N1 sized vector in bytes | |||
#define VEC_N1N2_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N1N2 sized vector in bytes | |||
#define VEC_K_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_K sized vector in bytes | |||
#define PARAM_T Define a threshold for decoding repetition code word (PARAM_T = (PARAM_N2 - 1) / 2) | |||
#define PARAM_DELTA Define the parameter delta of the scheme (correcting capacity of the BCH code) | |||
#define PARAM_M Define a positive integer | |||
#define PARAM_GF_MUL_ORDER Define the size of the multiplicative group of GF(2^m), i.e 2^m -1 | |||
#define PARAM_K Define the size of the information bits of the BCH code | |||
#define PARAM_G Define the size of the generator polynomial of BCH code | |||
#define PARAM_FFT The additive FFT takes a 2^PARAM_FFT polynomial as input | |||
We use the FFT to compute the roots of sigma, whose degree if PARAM_DELTA=60 | |||
The smallest power of 2 greater than 60+1 is 64=2^6 | |||
#define PARAM_FFT_T The additive FFT transpose computes a (2^PARAM_FFT_T)-sized syndrome vector | |||
We want to compute 2*PARAM_DELTA=120 syndromes | |||
The smallest power of 2 greater than 120 is 2^7 | |||
#define PARAM_BCH_POLY Generator polynomial of the BCH code | |||
#define SHA512_BYTES Define the size of SHA512 output in bytes | |||
#define SEED_BYTES Define the size of the seed in bytes | |||
#define SEEDEXPANDER_MAX_LENGTH Define the seed expander max length | |||
*/ | |||
#define PARAM_N 43669 | |||
#define PARAM_N1 766 | |||
#define PARAM_N2 57 | |||
#define PARAM_N1N2 43662 | |||
#define PARAM_OMEGA 101 | |||
#define PARAM_OMEGA_E 117 | |||
#define PARAM_OMEGA_R 117 | |||
#define PARAM_SECURITY 192 | |||
#define PARAM_DFR_EXP 128 | |||
#define SECRET_KEY_BYTES PQCLEAN_HQC1921CCA2_LEAKTIME_CRYPTO_SECRETKEYBYTES | |||
#define PUBLIC_KEY_BYTES PQCLEAN_HQC1921CCA2_LEAKTIME_CRYPTO_PUBLICKEYBYTES | |||
#define SHARED_SECRET_BYTES PQCLEAN_HQC1921CCA2_LEAKTIME_CRYPTO_BYTES | |||
#define CIPHERTEXT_BYTES PQCLEAN_HQC1921CCA2_LEAKTIME_CRYPTO_CIPHERTEXTBYTES | |||
#define UTILS_REJECTION_THRESHOLD 16768896 | |||
#define VEC_K_SIZE_BYTES CEIL_DIVIDE(PARAM_K, 8) | |||
#define VEC_N_SIZE_BYTES CEIL_DIVIDE(PARAM_N, 8) | |||
#define VEC_N1_SIZE_BYTES CEIL_DIVIDE(PARAM_N1, 8) | |||
#define VEC_N1N2_SIZE_BYTES CEIL_DIVIDE(PARAM_N1N2, 8) | |||
#define PARAM_T 28 | |||
#define PARAM_DELTA 57 | |||
#define PARAM_M 10 | |||
#define PARAM_GF_MUL_ORDER 1023 | |||
#define PARAM_K 256 | |||
#define PARAM_G 511 | |||
#define PARAM_FFT 6 | |||
#define PARAM_FFT_T 7 | |||
#define PARAM_BCH_POLY { \ | |||
1,1,0,0,0,0,1,0,0,1,1,0,1,1,0,1,0,1,1,0,0,1,0,0,1,1,1,1,1,1,0,0,1,1,0,1,1, \ | |||
1,1,0,1,1,1,1,0,1,0,0,0,1,0,0,1,1,1,0,1,1,0,1,0,1,1,1,0,1,0,1,0,0,1,0,0,0, \ | |||
0,1,1,1,1,0,1,1,1,1,1,0,0,0,0,1,0,0,1,0,0,1,1,1,0,0,0,1,1,0,0,1,0,1,0,0,0, \ | |||
1,0,0,0,0,1,0,0,0,1,0,1,1,0,0,0,0,1,1,0,0,1,1,0,1,0,1,0,1,0,1,1,1,1,0,1,0, \ | |||
0,1,1,0,1,0,1,1,0,0,1,1,0,1,1,1,1,1,0,1,0,1,1,1,0,1,0,0,0,1,1,0,1,1,1,1,0, \ | |||
1,1,1,1,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,1,1,1,1,0,0,1,1,0,1,0,0,0,0,1,0, \ | |||
0,1,0,0,1,0,1,0,0,1,1,0,1,0,1,1,1,1,1,0,1,1,0,1,0,1,1,1,1,1,1,0,0,0,1,0,1, \ | |||
1,1,1,1,1,0,1,0,1,0,1,1,0,0,0,1,1,0,0,1,1,0,1,1,1,1,1,1,1,0,0,0,1,1,1,1,0, \ | |||
1,0,0,0,1,0,0,1,1,0,1,1,0,0,1,0,1,1,0,1,0,1,0,1,1,0,0,0,0,0,1,1,1,1,1,1,1, \ | |||
1,1,1,0,1,1,0,1,0,1,1,1,1,1,1,1,0,1,1,0,1,1,0,0,0,1,0,0,1,1,1,1,1,0,1,0,1, \ | |||
0,0,0,0,1,0,1,1,1,1,0,1,0,0,0,0,0,1,0,0,1,0,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1, \ | |||
1,0,1,0,0,1,0,0,1,1,0,1,0,0,0,0,0,0,0,0,1,1,0,0,0,1,1,1,0,0,1,1,0,0,0,1,1, \ | |||
0,1,0,0,1,0,0,0,1,0,1,0,1,0,0,0,1,1,1,1,1,0,0,0,1,0,0,1,1,0,1,1,0,0,1,0,1, \ | |||
1,0,1,1,1,0,0,0,0,1,1,0,1,1,1,0,1,0,0,0,0,1,0,0,0,1,0,0,1,1 \ | |||
}; | |||
#define SHA512_BYTES 64 | |||
#define SEED_BYTES 40 | |||
#define SEEDEXPANDER_MAX_LENGTH 4294967295 | |||
#endif |
@@ -1,126 +0,0 @@ | |||
/** | |||
* @file parsing.c | |||
* @brief Functions to parse secret key, public key and ciphertext of the HQC scheme | |||
*/ | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
/** | |||
* @brief Parse a secret key into a string | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] sk String containing the secret key | |||
* @param[in] sk_seed Seed used to generate the secret key | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_secret_key_to_string(uint8_t *sk, const uint8_t *sk_seed, const uint8_t *pk) { | |||
memcpy(sk, sk_seed, SEED_BYTES); | |||
memcpy(sk + SEED_BYTES, pk, PUBLIC_KEY_BYTES); | |||
} | |||
/** | |||
* @brief Parse a secret key from a string | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] x uint8_t representation of vector x | |||
* @param[out] y uint8_t representation of vector y | |||
* @param[out] pk String containing the public key | |||
* @param[in] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_secret_key_from_string(uint8_t *x, uint32_t *y, uint8_t *pk, const uint8_t *sk) { | |||
AES_XOF_struct sk_seedexpander; | |||
uint8_t sk_seed[SEED_BYTES] = {0}; | |||
memcpy(sk_seed, sk, SEED_BYTES); | |||
seedexpander_init(&sk_seedexpander, sk_seed, sk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_fixed_weight(&sk_seedexpander, x, PARAM_OMEGA); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&sk_seedexpander, y, PARAM_OMEGA); | |||
memcpy(pk, sk + SEED_BYTES, PUBLIC_KEY_BYTES); | |||
} | |||
/** | |||
* @brief Parse a public key into a string | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b> | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[in] pk_seed Seed used to generate the public key | |||
* @param[in] s uint8_t representation of vector s | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_public_key_to_string(uint8_t *pk, const uint8_t *pk_seed, const uint8_t *s) { | |||
memcpy(pk, pk_seed, SEED_BYTES); | |||
memcpy(pk + SEED_BYTES, s, VEC_N_SIZE_BYTES); | |||
} | |||
/** | |||
* @brief Parse a public key from a string | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b> | |||
* | |||
* @param[out] h uint8_t representation of vector h | |||
* @param[out] s uint8_t representation of vector s | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_public_key_from_string(uint8_t *h, uint8_t *s, const uint8_t *pk) { | |||
AES_XOF_struct pk_seedexpander; | |||
uint8_t pk_seed[SEED_BYTES] = {0}; | |||
memcpy(pk_seed, pk, SEED_BYTES); | |||
seedexpander_init(&pk_seedexpander, pk_seed, pk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random(&pk_seedexpander, h); | |||
memcpy(s, pk + SEED_BYTES, VEC_N_SIZE_BYTES); | |||
} | |||
/** | |||
* @brief Parse a ciphertext into a string | |||
* | |||
* The ciphertext is composed of vectors <b>u</b>, <b>v</b> and hash <b>d</b>. | |||
* | |||
* @param[out] ct String containing the ciphertext | |||
* @param[in] u uint8_t representation of vector u | |||
* @param[in] v uint8_t representation of vector v | |||
* @param[in] d String containing the hash d | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_ciphertext_to_string(uint8_t *ct, const uint8_t *u, const uint8_t *v, const uint8_t *d) { | |||
memcpy(ct, u, VEC_N_SIZE_BYTES); | |||
memcpy(ct + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
memcpy(ct + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES, d, SHA512_BYTES); | |||
} | |||
/** | |||
* @brief Parse a ciphertext from a string | |||
* | |||
* The ciphertext is composed of vectors <b>u</b>, <b>v</b> and hash <b>d</b>. | |||
* | |||
* @param[out] u uint8_t representation of vector u | |||
* @param[out] v uint8_t representation of vector v | |||
* @param[out] d String containing the hash d | |||
* @param[in] ct String containing the ciphertext | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_ciphertext_from_string(uint8_t *u, uint8_t *v, uint8_t *d, const uint8_t *ct) { | |||
memcpy(u, ct, VEC_N_SIZE_BYTES); | |||
memcpy(v, ct + VEC_N_SIZE_BYTES, VEC_N1N2_SIZE_BYTES); | |||
memcpy(d, ct + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES, SHA512_BYTES); | |||
} |
@@ -1,20 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1921CCA2_LEAKTIME_PARSING_H | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_PARSING_H | |||
/** | |||
* @file parsing.h | |||
* @brief Header file for parsing.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_secret_key_to_string(uint8_t *sk, const uint8_t *sk_seed, const uint8_t *pk); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_secret_key_from_string(uint8_t *x, uint32_t *y, uint8_t *pk, const uint8_t *sk); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_public_key_to_string(uint8_t *pk, const uint8_t *pk_seed, const uint8_t *s); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_public_key_from_string(uint8_t *h, uint8_t *s, const uint8_t *pk); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_ciphertext_to_string(uint8_t *ct, const uint8_t *u, const uint8_t *v, const uint8_t *d); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_hqc_ciphertext_from_string(uint8_t *u, uint8_t *v, uint8_t *d, const uint8_t *ct); | |||
#endif |
@@ -1,100 +0,0 @@ | |||
/** | |||
* @file repetition.c | |||
* @brief Implementation of repetition codes | |||
*/ | |||
#include "parameters.h" | |||
#include "repetition.h" | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
static void array_to_rep_codeword(uint8_t *o, const uint8_t *v); | |||
/** | |||
* @brief Encoding each bit in the message m using the repetition code | |||
* | |||
* For reasons of clarity and comprehensibility, we do the encoding by storing the encoded bits in a String (each bit in an a uint8_t), | |||
* then we parse the obtained string to an compact array using the function array_to_rep_codeword(). | |||
* | |||
* @param[out] em Pointer to an array that is the code word | |||
* @param[in] m Pointer to an array that is the message | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_repetition_code_encode(uint8_t *em, const uint8_t *m) { | |||
uint8_t tmp[PARAM_N1N2] = {0}; | |||
uint8_t bit = 0; | |||
uint32_t index; | |||
for (size_t i = 0; i < (VEC_N1_SIZE_BYTES - 1); ++i) { | |||
for (uint8_t j = 0; j < 8; ++j) { | |||
bit = (m[i] >> j) & 0x01; | |||
index = (8 * (uint32_t)i + j) * PARAM_N2; | |||
for (uint8_t k = 0; k < PARAM_N2; ++k) { | |||
tmp[index + k] = bit; | |||
} | |||
} | |||
} | |||
for (uint8_t j = 0; j < (PARAM_N1 % 8); ++j) { | |||
bit = (m[VEC_N1_SIZE_BYTES - 1] >> j) & 0x01; | |||
index = (8 * (VEC_N1_SIZE_BYTES - 1) + j) * PARAM_N2; | |||
for (uint8_t k = 0; k < PARAM_N2; ++k) { | |||
tmp[index + k] = bit; | |||
} | |||
} | |||
array_to_rep_codeword(em, tmp); | |||
} | |||
/** | |||
* @brief Decoding the code words to a message using the repetition code | |||
* | |||
* We use a majority decoding. In fact we have that PARAM_N2 = 2 * PARAM_T + 1, thus, | |||
* if the Hamming weight of the vector is greater than PARAM_T, the code word is decoded | |||
* to 1 and 0 otherwise. | |||
* | |||
* @param[out] m Pointer to an array that is the message | |||
* @param[in] em Pointer to an array that is the code word | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_repetition_code_decode(uint8_t *m, const uint8_t *em) { | |||
size_t t = 0; // m index | |||
uint8_t k = PARAM_N2; // block counter | |||
uint8_t ones = 0; // number of 1 in the current block | |||
for (size_t i = 0; i < VEC_N1N2_SIZE_BYTES; ++i) { | |||
for (uint8_t j = 0; j < 8; ++j) { | |||
ones += (em[i] >> j) & 0x01; | |||
if (--k) { | |||
continue; | |||
} | |||
m[t / 8] |= (ones > PARAM_T) << t % 8; | |||
++t; | |||
k = PARAM_N2; | |||
ones = 0; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Parse an array to an compact array | |||
* | |||
* @param[out] o Pointer to an array | |||
* @param[in] v Pointer to an array | |||
*/ | |||
static void array_to_rep_codeword(uint8_t *o, const uint8_t *v) { | |||
for (size_t i = 0; i < (VEC_N1N2_SIZE_BYTES - 1); ++i) { | |||
for (uint8_t j = 0; j < 8; ++j) { | |||
o[i] |= v[j + 8 * i] << j; | |||
} | |||
} | |||
for (uint8_t j = 0; j < PARAM_N1N2 % 8; ++j) { | |||
o[VEC_N1N2_SIZE_BYTES - 1] |= (v[j + 8 * (VEC_N1N2_SIZE_BYTES - 1)]) << j; | |||
} | |||
} |
@@ -1,14 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1921CCA2_LEAKTIME_REPETITION_H | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_REPETITION_H | |||
/** | |||
* @file repetition.h | |||
* @brief Header file for repetition.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_repetition_code_encode(uint8_t *em, const uint8_t *m); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_repetition_code_decode(uint8_t *m, const uint8_t *em); | |||
#endif |
@@ -1,42 +0,0 @@ | |||
/** | |||
* @file tensor.c | |||
* @brief Implementation of tensor code | |||
*/ | |||
#include "bch.h" | |||
#include "parameters.h" | |||
#include "repetition.h" | |||
#include "tensor.h" | |||
#include <stdint.h> | |||
/** | |||
* @brief Encoding the message m to a code word em using the tensor code | |||
* | |||
* First we encode the message using the BCH code, then with the repetition code to obtain | |||
* a tensor code word. | |||
* | |||
* @param[out] em Pointer to an array that is the tensor code word | |||
* @param[in] m Pointer to an array that is the message | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_tensor_code_encode(uint8_t *em, const uint8_t *m) { | |||
uint8_t tmp[VEC_N1_SIZE_BYTES] = {0}; | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_bch_code_encode(tmp, m); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_repetition_code_encode(em, tmp); | |||
} | |||
/** | |||
* @brief Decoding the code word em to a message m using the tensor code | |||
* | |||
* @param[out] m Pointer to an array that is the message | |||
* @param[in] em Pointer to an array that is the code word | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_tensor_code_decode(uint8_t *m, const uint8_t *em) { | |||
uint8_t tmp[VEC_N1_SIZE_BYTES] = {0}; | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_repetition_code_decode(tmp, em); | |||
PQCLEAN_HQC1921CCA2_LEAKTIME_bch_code_decode(m, tmp); | |||
} |
@@ -1,14 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1921CCA2_LEAKTIME_TENSOR_H | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_TENSOR_H | |||
/** | |||
* @file tensor.h | |||
* @brief Header file for tensor.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_tensor_code_encode(uint8_t *em, const uint8_t *m); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_tensor_code_decode(uint8_t *m, const uint8_t *em); | |||
#endif |
@@ -1,69 +0,0 @@ | |||
#include "util.h" | |||
#include "stddef.h" | |||
#include "assert.h" | |||
/* These functions should help with endianness-safe conversions | |||
* | |||
* load8 and store8 are copied from the McEliece implementations, | |||
* which are in the public domain. | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_store8(unsigned char *out, uint64_t in) { | |||
out[0] = (in >> 0x00) & 0xFF; | |||
out[1] = (in >> 0x08) & 0xFF; | |||
out[2] = (in >> 0x10) & 0xFF; | |||
out[3] = (in >> 0x18) & 0xFF; | |||
out[4] = (in >> 0x20) & 0xFF; | |||
out[5] = (in >> 0x28) & 0xFF; | |||
out[6] = (in >> 0x30) & 0xFF; | |||
out[7] = (in >> 0x38) & 0xFF; | |||
} | |||
uint64_t PQCLEAN_HQC1921CCA2_LEAKTIME_load8(const unsigned char *in) { | |||
uint64_t ret = in[7]; | |||
for (int8_t i = 6; i >= 0; i--) { | |||
ret <<= 8; | |||
ret |= in[i]; | |||
} | |||
return ret; | |||
} | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_load8_arr(uint64_t *out64, size_t outlen, const uint8_t *in8, size_t inlen) { | |||
size_t index_in = 0; | |||
size_t index_out = 0; | |||
// first copy by 8 bytes | |||
if (inlen >= 8 && outlen >= 1) { | |||
while (index_out < outlen && index_in + 8 <= inlen) { | |||
out64[index_out] = PQCLEAN_HQC1921CCA2_LEAKTIME_load8(in8 + index_in); | |||
index_in += 8; | |||
index_out += 1; | |||
} | |||
} | |||
// we now need to do the last 7 bytes if necessary | |||
if (index_in >= inlen || index_out >= outlen) { | |||
return; | |||
} | |||
out64[index_out] = in8[inlen - 1]; | |||
for (int8_t i = (int8_t)(inlen - index_in) - 2; i >= 0; i--) { | |||
out64[index_out] <<= 8; | |||
out64[index_out] |= in8[index_in + i]; | |||
} | |||
} | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_store8_arr(uint8_t *out8, size_t outlen, const uint64_t *in64, size_t inlen) { | |||
for (size_t index_out = 0, index_in = 0; index_out < outlen && index_in < inlen;) { | |||
out8[index_out] = (in64[index_in] >> ((index_out % 8) * 8)) & 0xFF; | |||
index_out++; | |||
if (index_out % 8 == 0) { | |||
index_in++; | |||
} | |||
} | |||
} |
@@ -1,9 +0,0 @@ | |||
/* These functions should help with endianness-safe conversions */ | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_store8(unsigned char *out, uint64_t in); | |||
uint64_t PQCLEAN_HQC1921CCA2_LEAKTIME_load8(const unsigned char *in); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_load8_arr(uint64_t *out64, size_t outlen, const uint8_t *in8, size_t inlen); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_store8_arr(uint8_t *out8, size_t outlen, const uint64_t *in64, size_t inlen); |
@@ -1,224 +0,0 @@ | |||
/** | |||
* @file vector.c | |||
* @brief Implementation of vectors sampling and some utilities for the HQC scheme | |||
*/ | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "randombytes.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
/** | |||
* @brief Generates a vector of a given Hamming weight | |||
* | |||
* This function generates uniformly at random a binary vector of a Hamming weight equal to the parameter <b>weight</b>. The vector | |||
* is stored by position. | |||
* To generate the vector we have to sample uniformly at random values in the interval [0, PARAM_N -1]. Suppose the PARAM_N is equal to \f$ 70853 \f$, to select a position \f$ r\f$ the function works as follow: | |||
* 1. It makes a call to the seedexpander function to obtain a random number \f$ x\f$ in \f$ [0, 2^{24}[ \f$. | |||
* 2. Let \f$ t = \lfloor {2^{24} \over 70853} \rfloor \times 70853\f$ | |||
* 3. If \f$ x \geq t\f$, go to 1 | |||
* 4. It return \f$ r = x \mod 70853\f$ | |||
* | |||
* The parameter \f$ t \f$ is precomputed and it's denoted by UTILS_REJECTION_THRESHOLD (see the file parameters.h). | |||
* | |||
* @param[in] v Pointer to an array | |||
* @param[in] weight Integer that is the Hamming weight | |||
* @param[in] ctx Pointer to the context of the seed expander | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(AES_XOF_struct *ctx, uint32_t *v, uint16_t weight) { | |||
size_t random_bytes_size = 3 * weight; | |||
uint8_t rand_bytes[3 * PARAM_OMEGA_R] = {0}; // weight is expected to be <= PARAM_OMEGA_R | |||
uint32_t random_data = 0; | |||
uint8_t exist = 0; | |||
size_t j = 0; | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
for (uint32_t i = 0; i < weight; ++i) { | |||
exist = 0; | |||
do { | |||
if (j == random_bytes_size) { | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
j = 0; | |||
} | |||
random_data = ((uint32_t) rand_bytes[j++]) << 16; | |||
random_data |= ((uint32_t) rand_bytes[j++]) << 8; | |||
random_data |= rand_bytes[j++]; | |||
} while (random_data >= UTILS_REJECTION_THRESHOLD); | |||
random_data = random_data % PARAM_N; | |||
for (uint32_t k = 0; k < i; k++) { | |||
if (v[k] == random_data) { | |||
exist = 1; | |||
} | |||
} | |||
if (exist == 1) { | |||
i--; | |||
} else { | |||
v[i] = random_data; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Generates a vector of a given Hamming weight | |||
* | |||
* This function generates uniformly at random a binary vector of a Hamming weight equal to the parameter <b>weight</b>. | |||
* To generate the vector we have to sample uniformly at random values in the interval [0, PARAM_N -1]. Suppose the PARAM_N is equal to \f$ 70853 \f$, to select a position \f$ r\f$ the function works as follow: | |||
* 1. It makes a call to the seedexpander function to obtain a random number \f$ x\f$ in \f$ [0, 2^{24}[ \f$. | |||
* 2. Let \f$ t = \lfloor {2^{24} \over 70853} \rfloor \times 70853\f$ | |||
* 3. If \f$ x \geq t\f$, go to 1 | |||
* 4. It return \f$ r = x \mod 70853\f$ | |||
* | |||
* The parameter \f$ t \f$ is precomputed and it's denoted by UTILS_REJECTION_THRESHOLD (see the file parameters.h). | |||
* | |||
* @param[in] v Pointer to an array | |||
* @param[in] weight Integer that is the Hamming weight | |||
* @param[in] ctx Pointer to the context of the seed expander | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_fixed_weight(AES_XOF_struct *ctx, uint8_t *v, uint16_t weight) { | |||
size_t random_bytes_size = 3 * weight; | |||
uint8_t rand_bytes[3 * PARAM_OMEGA_R] = {0}; // weight is expected to be <= PARAM_OMEGA_R | |||
uint32_t random_data = 0; | |||
uint32_t tmp[PARAM_OMEGA_R] = {0}; | |||
uint8_t exist = 0; | |||
size_t j = 0; | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
for (uint32_t i = 0; i < weight; ++i) { | |||
exist = 0; | |||
do { | |||
if (j == random_bytes_size) { | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
j = 0; | |||
} | |||
random_data = ((uint32_t) rand_bytes[j++]) << 16; | |||
random_data |= ((uint32_t) rand_bytes[j++]) << 8; | |||
random_data |= rand_bytes[j++]; | |||
} while (random_data >= UTILS_REJECTION_THRESHOLD); | |||
random_data = random_data % PARAM_N; | |||
for (uint32_t k = 0; k < i; k++) { | |||
if (tmp[k] == random_data) { | |||
exist = 1; | |||
} | |||
} | |||
if (exist == 1) { | |||
i--; | |||
} else { | |||
tmp[i] = random_data; | |||
} | |||
} | |||
for (uint16_t i = 0; i < weight; ++i) { | |||
int32_t index = tmp[i] / 8; | |||
int32_t pos = tmp[i] % 8; | |||
v[index] |= 1 << pos; | |||
} | |||
} | |||
/** | |||
* @brief Generates a random vector of dimension <b>PARAM_N</b> | |||
* | |||
* This function generates a random binary vector of dimension <b>PARAM_N</b>. It generates a random | |||
* array of bytes using the seedexpander function, and drop the extra bits using a mask. | |||
* | |||
* @param[in] v Pointer to an array | |||
* @param[in] ctx Pointer to the context of the seed expander | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random(AES_XOF_struct *ctx, uint8_t *v) { | |||
uint8_t rand_bytes[VEC_N_SIZE_BYTES] = {0}; | |||
seedexpander(ctx, rand_bytes, VEC_N_SIZE_BYTES); | |||
memcpy(v, rand_bytes, VEC_N_SIZE_BYTES); | |||
v[VEC_N_SIZE_BYTES - 1] &= BITMASK(PARAM_N, 8); | |||
} | |||
/** | |||
* @brief Generates a random vector | |||
* | |||
* This function generates a random binary vector. It uses the the randombytes function. | |||
* | |||
* @param[in] v Pointer to an array | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_from_randombytes(uint8_t *v) { | |||
uint8_t rand_bytes [VEC_K_SIZE_BYTES] = {0}; | |||
randombytes(rand_bytes, VEC_K_SIZE_BYTES); | |||
memcpy(v, rand_bytes, VEC_K_SIZE_BYTES); | |||
} | |||
/** | |||
* @brief Adds two vectors | |||
* | |||
* @param[out] o Pointer to an array that is the result | |||
* @param[in] v1 Pointer to an array that is the first vector | |||
* @param[in] v2 Pointer to an array that is the second vector | |||
* @param[in] size Integer that is the size of the vectors | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_add(uint8_t *o, const uint8_t *v1, const uint8_t *v2, uint32_t size) { | |||
for (uint32_t i = 0; i < size; ++i) { | |||
o[i] = v1[i] ^ v2[i]; | |||
} | |||
} | |||
/** | |||
* @brief Compares two vectors | |||
* | |||
* @param[in] v1 Pointer to an array that is first vector | |||
* @param[in] v2 Pointer to an array that is second vector | |||
* @param[in] size Integer that is the size of the vectors | |||
* @returns 0 if the vectors are equals and a negative/psotive value otherwise | |||
*/ | |||
int PQCLEAN_HQC1921CCA2_LEAKTIME_vect_compare(const uint8_t *v1, const uint8_t *v2, uint32_t size) { | |||
return memcmp(v1, v2, size); | |||
} | |||
/** | |||
* @brief Resize a vector so that it contains <b>size_o</b> bits | |||
* | |||
* @param[out] o Pointer to the output vector | |||
* @param[in] size_o Integer that is the size of the output vector in bits | |||
* @param[in] v Pointer to the input vector | |||
* @param[in] size_v Integer that is the size of the input vector in bits | |||
*/ | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_resize(uint8_t *o, uint32_t size_o, const uint8_t *v, uint32_t size_v) { | |||
if (size_o < size_v) { | |||
uint8_t mask = 0x7F; | |||
int8_t val = 8 - (size_o % 8); | |||
memcpy(o, v, VEC_N1N2_SIZE_BYTES); | |||
for (int8_t i = 0; i < val; ++i) { | |||
o[VEC_N1N2_SIZE_BYTES - 1] &= (mask >> i); | |||
} | |||
} else { | |||
memcpy(o, v, CEIL_DIVIDE(size_v, 8)); | |||
} | |||
} |
@@ -1,22 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1921CCA2_LEAKTIME_VECTOR_H | |||
#define PQCLEAN_HQC1921CCA2_LEAKTIME_VECTOR_H | |||
/** | |||
* @file vector.h | |||
* @brief Header file for vector.c | |||
*/ | |||
#include "nistseedexpander.h" | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(AES_XOF_struct *ctx, uint32_t *v, uint16_t weight); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_fixed_weight(AES_XOF_struct *ctx, uint8_t *v, uint16_t weight); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random(AES_XOF_struct *ctx, uint8_t *v); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_set_random_from_randombytes(uint8_t *v); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_add(uint8_t *o, const uint8_t *v1, const uint8_t *v2, uint32_t size); | |||
int PQCLEAN_HQC1921CCA2_LEAKTIME_vect_compare(const uint8_t *v1, const uint8_t *v2, uint32_t size); | |||
void PQCLEAN_HQC1921CCA2_LEAKTIME_vect_resize(uint8_t *o, uint32_t size_o, const uint8_t *v, uint32_t size_v); | |||
#endif |
@@ -1,23 +0,0 @@ | |||
name: HQC_192_2_CCA2 | |||
type: kem | |||
claimed-nist-level: 3 | |||
claimed-security: IND-CCA2 | |||
length-public-key: 5884 | |||
length-ciphertext: 11749 | |||
length-secret-key: 5924 | |||
length-shared-secret: 64 | |||
nistkat-sha256: 838916e26585828d15cabb7a0a0b9dabb63986e432735b7f6cf2ee0e823bcca3 | |||
principal-submitters: | |||
- Carlos Aguilar Melchor | |||
- Nicolas Aragon | |||
- Slim Bettaieb | |||
- Loïc Bidoux | |||
- Olivier Blazy | |||
- Jean-Christophe Deneuville | |||
- Philippe Gaborit | |||
- Edoardo Persichetti | |||
- Gilles Zémor | |||
auxiliary-submitters: [] | |||
implementations: | |||
- name: leaktime | |||
version: https://pqc-hqc.org/doc/hqc-reference-implementation_2019-08-24.zip |
@@ -1 +0,0 @@ | |||
Public domain |
@@ -1,19 +0,0 @@ | |||
# This Makefile can be used with GNU Make or BSD Make | |||
LIB=libhqc-192-2-cca2_leaktime.a | |||
HEADERS=api.h bch.h fft.h gf.h gf2x.h hqc.h parameters.h parsing.h repetition.h tensor.h vector.h util.h | |||
OBJECTS=bch.o fft.o gf.o gf2x.o hqc.o kem.o parsing.o repetition.o tensor.o vector.o util.o | |||
CFLAGS=-O3 -Wall -Wextra -Wpedantic -Wvla -Werror -Wmissing-prototypes -Wredundant-decls -std=c99 -I../../../common $(EXTRAFLAGS) | |||
all: $(LIB) | |||
%.o: %.c $(HEADERS) | |||
$(CC) $(CFLAGS) -c -o $@ $< | |||
$(LIB): $(OBJECTS) | |||
$(AR) -r $@ $(OBJECTS) | |||
clean: | |||
$(RM) $(OBJECTS) | |||
$(RM) $(LIB) |
@@ -1,23 +0,0 @@ | |||
# This Makefile can be used with Microsoft Visual Studio's nmake using the command: | |||
# nmake /f Makefile.Microsoft_nmake | |||
LIBRARY=libhqc-192-2-cca2_leaktime.lib | |||
OBJECTS=bch.obj fft.obj gf.obj gf2x.obj hqc.obj kem.obj parsing.obj repetition.obj tensor.obj vector.obj util.obj | |||
# We ignore warning C4127: we sometimes use a conditional that depending | |||
# on the parameters results in a case where if (const) is the case. | |||
# The compiler should just optimise this away, but on MSVC we get | |||
# a compiler complaint. | |||
CFLAGS=/nologo /O2 /I ..\..\..\common /W4 /WX /wd4127 | |||
all: $(LIBRARY) | |||
# Make sure objects are recompiled if headers change. | |||
$(OBJECTS): *.h | |||
$(LIBRARY): $(OBJECTS) | |||
LIB.EXE /NOLOGO /WX /OUT:$@ $** | |||
clean: | |||
-DEL $(OBJECTS) | |||
-DEL $(LIBRARY) |
@@ -1,25 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1922CCA2_LEAKTIME_API_H | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_API_H | |||
/** | |||
* \file api.h | |||
* \brief NIST KEM API used by the HQC_KEM IND-CCA2 scheme | |||
*/ | |||
#include <stdint.h> | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_CRYPTO_ALGNAME "HQC_192_2_CCA2" | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_CRYPTO_SECRETKEYBYTES 5924 | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_CRYPTO_PUBLICKEYBYTES 5884 | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_CRYPTO_BYTES 64 | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_CRYPTO_CIPHERTEXTBYTES 11749 | |||
// As a technicality, the public key is appended to the secret key in order to respect the NIST API. | |||
// Without this constraint, CRYPTO_SECRETKEYBYTES would be defined as 32 | |||
int PQCLEAN_HQC1922CCA2_LEAKTIME_crypto_kem_keypair(uint8_t *pk, uint8_t *sk); | |||
int PQCLEAN_HQC1922CCA2_LEAKTIME_crypto_kem_enc(uint8_t *ct, uint8_t *ss, const uint8_t *pk); | |||
int PQCLEAN_HQC1922CCA2_LEAKTIME_crypto_kem_dec(uint8_t *ss, const uint8_t *ct, const uint8_t *sk); | |||
#endif |
@@ -1,295 +0,0 @@ | |||
/** | |||
* @file bch.c | |||
* Constant time implementation of BCH codes | |||
*/ | |||
#include "bch.h" | |||
#include "fft.h" | |||
#include "gf.h" | |||
#include "parameters.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
static void unpack_message(uint8_t *message_unpacked, const uint8_t *message); | |||
static void lfsr_encode(uint8_t *codeword, const uint8_t *message); | |||
static void pack_codeword(uint8_t *codeword, const uint8_t *codeword_unpacked); | |||
static size_t compute_elp(uint16_t *sigma, const uint16_t *syndromes); | |||
static void message_from_codeword(uint8_t *message, const uint8_t *codeword); | |||
static void compute_syndromes(uint16_t *syndromes, const uint8_t *vector); | |||
static void compute_roots(uint8_t *error, const uint16_t *sigma); | |||
/** | |||
* @brief Unpacks the message message to the array message_unpacked where each byte stores a bit of the message | |||
* | |||
* @param[out] message_unpacked Array of VEC_K_SIZE_BYTES bytes receiving the unpacked message | |||
* @param[in] message Array of PARAM_K bytes storing the packed message | |||
*/ | |||
static void unpack_message(uint8_t *message_unpacked, const uint8_t *message) { | |||
for (size_t i = 0; i < (VEC_K_SIZE_BYTES - (PARAM_K % 8 != 0)); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
message_unpacked[j + 8 * i] = (message[i] >> j) & 0x01; | |||
} | |||
} | |||
for (int8_t j = 0; j < PARAM_K % 8; ++j) { | |||
message_unpacked[j + 8 * (VEC_K_SIZE_BYTES - 1)] = (message[VEC_K_SIZE_BYTES - 1] >> j) & 0x01; | |||
} | |||
} | |||
/** | |||
* @brief Encodes the message message to a codeword codeword using the generator polynomial bch_poly of the code | |||
* | |||
* @param[out] codeword Array of PARAM_N1 bytes receiving the codeword | |||
* @param[in] message Array of PARAM_K bytes storing the message to encode | |||
*/ | |||
static void lfsr_encode(uint8_t *codeword, const uint8_t *message) { | |||
uint8_t gate_value = 0; | |||
uint8_t bch_poly[PARAM_G] = PARAM_BCH_POLY; | |||
// Compute the Parity-check digits | |||
for (int16_t i = PARAM_K - 1; i >= 0; --i) { | |||
gate_value = message[i] ^ codeword[PARAM_N1 - PARAM_K - 1]; | |||
for (size_t j = PARAM_N1 - PARAM_K - 1; j; --j) { | |||
codeword[j] = codeword[j - 1] ^ (-gate_value & bch_poly[j]); | |||
} | |||
codeword[0] = gate_value; | |||
} | |||
// Add the message | |||
memcpy(codeword + PARAM_N1 - PARAM_K, message, PARAM_K); | |||
} | |||
/** | |||
* @brief Packs the codeword from an array codeword_unpacked where each byte stores a bit to a compact array codeword | |||
* | |||
* @param[out] codeword Array of VEC_N1_SIZE_BYTES bytes receiving the packed codeword | |||
* @param[in] codeword_unpacked Array of PARAM_N1 bytes storing the unpacked codeword | |||
*/ | |||
static void pack_codeword(uint8_t *codeword, const uint8_t *codeword_unpacked) { | |||
for (size_t i = 0; i < (VEC_N1_SIZE_BYTES - (PARAM_N1 % 8 != 0)); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
codeword[i] |= codeword_unpacked[j + 8 * i] << j; | |||
} | |||
} | |||
for (size_t j = 0; j < PARAM_N1 % 8; ++j) { | |||
codeword[VEC_N1_SIZE_BYTES - 1] |= codeword_unpacked[j + 8 * (VEC_N1_SIZE_BYTES - 1)] << j; | |||
} | |||
} | |||
/** | |||
* @brief Encodes a message message of PARAM_K bits to a BCH codeword codeword of PARAM_N1 bits | |||
* | |||
* Following @cite lin1983error (Chapter 4 - Cyclic Codes), | |||
* We perform a systematic encoding using a linear (PARAM_N1 - PARAM_K)-stage shift register | |||
* with feedback connections based on the generator polynomial bch_poly of the BCH code. | |||
* | |||
* @param[out] codeword Array of size VEC_N1_SIZE_BYTES receiving the encoded message | |||
* @param[in] message Array of size VEC_K_SIZE_BYTES storing the message | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_bch_code_encode(uint8_t *codeword, const uint8_t *message) { | |||
uint8_t message_unpacked[PARAM_K]; | |||
uint8_t codeword_unpacked[PARAM_N1] = {0}; | |||
unpack_message(message_unpacked, message); | |||
lfsr_encode(codeword_unpacked, message_unpacked); | |||
pack_codeword(codeword, codeword_unpacked); | |||
} | |||
/** | |||
* @brief Computes the error locator polynomial (ELP) sigma | |||
* | |||
* This is a constant time implementation of Berlekamp's simplified algorithm (see @cite joiner1995decoding). <br> | |||
* We use the letter p for rho which is initialized at -1/2. <br> | |||
* The array X_sigma_p represents the polynomial X^(2(mu-rho))*sigma_p(X). <br> | |||
* Instead of maintaining a list of sigmas, we update in place both sigma and X_sigma_p. <br> | |||
* sigma_copy serves as a temporary save of sigma in case X_sigma_p needs to be updated. <br> | |||
* We can properly correct only if the degree of sigma does not exceed PARAM_DELTA. | |||
* This means only the first PARAM_DELTA + 1 coefficients of sigma are of value | |||
* and we only need to save its first PARAM_DELTA - 1 coefficients. | |||
* | |||
* @returns the degree of the ELP sigma | |||
* @param[out] sigma Array of size (at least) PARAM_DELTA receiving the ELP | |||
* @param[in] syndromes Array of size (at least) 2*PARAM_DELTA storing the syndromes | |||
*/ | |||
static size_t compute_elp(uint16_t *sigma, const uint16_t *syndromes) { | |||
sigma[0] = 1; | |||
size_t deg_sigma = 0; | |||
size_t deg_sigma_p = 0; | |||
uint16_t sigma_copy[PARAM_DELTA - 1] = {0}; | |||
size_t deg_sigma_copy = 0; | |||
uint16_t X_sigma_p[PARAM_DELTA + 1] = {0, 1}; | |||
int32_t pp = -1; // 2*rho | |||
uint16_t d_p = 1; | |||
uint16_t d = syndromes[0]; | |||
for (size_t mu = 0; mu < PARAM_DELTA; ++mu) { | |||
// Save sigma in case we need it to update X_sigma_p | |||
memcpy(sigma_copy, sigma, 2 * (PARAM_DELTA - 1)); | |||
deg_sigma_copy = deg_sigma; | |||
uint16_t dd = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(d, PQCLEAN_HQC1922CCA2_LEAKTIME_gf_inverse(d_p)); // 0 if(d == 0) | |||
for (size_t i = 1; (i <= 2 * mu + 1) && (i <= PARAM_DELTA); ++i) { | |||
sigma[i] ^= PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(dd, X_sigma_p[i]); | |||
} | |||
size_t deg_X = 2 * mu - pp; // 2*(mu-rho) | |||
size_t deg_X_sigma_p = deg_X + deg_sigma_p; | |||
// mask1 = 0xffff if(d != 0) and 0 otherwise | |||
int16_t mask1 = -((uint16_t) - d >> 15); | |||
// mask2 = 0xffff if(deg_X_sigma_p > deg_sigma) and 0 otherwise | |||
int16_t mask2 = -((uint16_t) (deg_sigma - deg_X_sigma_p) >> 15); | |||
// mask12 = 0xffff if the deg_sigma increased and 0 otherwise | |||
int16_t mask12 = mask1 & mask2; | |||
deg_sigma = (mask12 & deg_X_sigma_p) ^ (~mask12 & deg_sigma); | |||
if (mu == PARAM_DELTA - 1) { | |||
break; | |||
} | |||
// Update pp, d_p and X_sigma_p if needed | |||
pp = (mask12 & (2 * mu)) ^ (~mask12 & pp); | |||
d_p = (mask12 & d) ^ (~mask12 & d_p); | |||
for (size_t i = PARAM_DELTA - 1; i; --i) { | |||
X_sigma_p[i + 1] = (mask12 & sigma_copy[i - 1]) ^ (~mask12 & X_sigma_p[i - 1]); | |||
} | |||
X_sigma_p[1] = 0; | |||
X_sigma_p[0] = 0; | |||
deg_sigma_p = (mask12 & deg_sigma_copy) ^ (~mask12 & deg_sigma_p); | |||
// Compute the next discrepancy | |||
d = syndromes[2 * mu + 2]; | |||
for (size_t i = 1; (i <= 2 * mu + 1) && (i <= PARAM_DELTA); ++i) { | |||
d ^= PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(sigma[i], syndromes[2 * mu + 2 - i]); | |||
} | |||
} | |||
return deg_sigma; | |||
} | |||
/** | |||
* @brief Retrieves the message message from the codeword codeword | |||
* | |||
* Since we performed a systematic encoding, the message is the last PARAM_K bits of the codeword. | |||
* | |||
* @param[out] message Array of size VEC_K_SIZE_BYTES receiving the message | |||
* @param[in] codeword Array of size VEC_N1_SIZE_BYTES storing the codeword | |||
*/ | |||
static void message_from_codeword(uint8_t *message, const uint8_t *codeword) { | |||
int32_t val = PARAM_N1 - PARAM_K; | |||
uint8_t mask1 = 0xff << val % 8; | |||
uint8_t mask2 = 0xff >> (8 - val % 8); | |||
size_t index = val / 8; | |||
for (size_t i = 0; i < VEC_K_SIZE_BYTES - 1; ++i) { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
uint8_t message2 = (codeword[++index] & mask2) << (8 - val % 8); | |||
message[i] = message1 | message2; | |||
} | |||
// Last byte (8-val % 8 is the number of bits given by message1) | |||
if ((PARAM_K % 8 == 0) || (8 - val % 8 < PARAM_K % 8)) { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
uint8_t message2 = (codeword[++index] & mask2) << (8 - val % 8); | |||
message[VEC_K_SIZE_BYTES - 1] = message1 | message2; | |||
} else { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
message[VEC_K_SIZE_BYTES - 1] = message1; | |||
} | |||
} | |||
/** | |||
* @brief Computes the 2^PARAM_DELTA syndromes from the received vector vector | |||
* | |||
* Syndromes are the sum of powers of alpha weighted by vector's coefficients. | |||
* To do so, we use the additive FFT transpose, which takes as input a family w of GF(2^PARAM_M) elements | |||
* and outputs the weighted power sums of these w. <br> | |||
* Therefore, this requires twisting and applying a permutation before feeding vector to the fft transpose. <br> | |||
* For more details see Berstein, Chou and Schawbe's explanations: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] syndromes Array of size 2^(PARAM_FFT_T) receiving the 2*PARAM_DELTA syndromes | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES storing the received word | |||
*/ | |||
static void compute_syndromes(uint16_t *syndromes, const uint8_t *vector) { | |||
uint16_t w[1 << PARAM_M]; | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(w, vector); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_fft_t(syndromes, w, 2 * PARAM_DELTA); | |||
} | |||
/** | |||
* @brief Computes the error polynomial error from the error locator polynomial sigma | |||
* | |||
* See function fft for more details. | |||
* | |||
* @param[out] err Array of VEC_N1_SIZE_BYTES elements receiving the error polynomial | |||
* @param[in] sigma Array of 2^PARAM_FFT elements storing the error locator polynomial | |||
*/ | |||
static void compute_roots(uint8_t *error, const uint16_t *sigma) { | |||
uint16_t w[1 << PARAM_M] = {0}; // w will receive the evaluation of sigma in all field elements | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_fft(w, sigma, PARAM_DELTA + 1); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_fft_retrieve_bch_error_poly(error, w); | |||
} | |||
/** | |||
* @brief Decodes the received word | |||
* | |||
* This function relies on four steps: | |||
* <ol> | |||
* <li> The first step, done by additive FFT transpose, is the computation of the 2*PARAM_DELTA syndromes. | |||
* <li> The second step is the computation of the error-locator polynomial sigma. | |||
* <li> The third step, done by additive FFT, is finding the error-locator numbers by calculating the roots of the polynomial sigma and takings their inverses. | |||
* <li> The fourth step is the correction of the errors in the received polynomial. | |||
* </ol> | |||
* For a more complete picture on BCH decoding, see Shu. Lin and Daniel J. Costello in Error Control Coding: Fundamentals and Applications @cite lin1983error | |||
* | |||
* @param[out] message Array of size VEC_K_SIZE_BYTES receiving the decoded message | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES storing the received word | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_bch_code_decode(uint8_t *message, uint8_t *vector) { | |||
uint16_t syndromes[1 << PARAM_FFT_T]; | |||
uint16_t sigma[1 << PARAM_FFT] = {0}; | |||
uint8_t error[(1 << PARAM_M) / 8] = {0}; | |||
// Calculate the 2*PARAM_DELTA syndromes | |||
compute_syndromes(syndromes, vector); | |||
// Compute the error locator polynomial sigma | |||
// Sigma's degree is at most PARAM_DELTA but the FFT requires the extra room | |||
compute_elp(sigma, syndromes); | |||
// Compute the error polynomial error | |||
compute_roots(error, sigma); | |||
// Add the error polynomial to the received polynomial | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_add(vector, vector, error, VEC_N1_SIZE_BYTES); | |||
// Retrieve the message from the decoded codeword | |||
message_from_codeword(message, vector); | |||
} |
@@ -1,16 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1922CCA2_LEAKTIME_BCH_H | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_BCH_H | |||
/** | |||
* @file bch.h | |||
* Header file of bch.c | |||
*/ | |||
#include "parameters.h" | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_bch_code_encode(uint8_t *codeword, const uint8_t *message); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_bch_code_decode(uint8_t *message, uint8_t *vector); | |||
#endif |
@@ -1,628 +0,0 @@ | |||
/** | |||
* @file fft.c | |||
* Implementation of the additive FFT and its transpose. | |||
* This implementation is based on the paper from Gao and Mateer: <br> | |||
* Shuhong Gao and Todd Mateer, Additive Fast Fourier Transforms over Finite Fields, | |||
* IEEE Transactions on Information Theory 56 (2010), 6265--6272. | |||
* http://www.math.clemson.edu/~sgao/papers/GM10.pdf <br> | |||
* and includes improvements proposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
*/ | |||
#include "fft.h" | |||
#include "gf.h" | |||
#include "parameters.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
static void compute_fft_betas(uint16_t *betas); | |||
static void compute_subset_sums(uint16_t *subset_sums, const uint16_t *set, size_t set_size); | |||
static void radix_t(uint16_t *f, const uint16_t *f0, const uint16_t *f1, uint32_t m_f); | |||
static void fft_t_rec(uint16_t *f, const uint16_t *w, size_t f_coeffs, uint8_t m, uint32_t m_f, const uint16_t *betas); | |||
static void radix(uint16_t *f0, uint16_t *f1, const uint16_t *f, uint32_t m_f); | |||
static void fft_rec(uint16_t *w, uint16_t *f, size_t f_coeffs, uint8_t m, uint32_t m_f, const uint16_t *betas); | |||
/** | |||
* @brief Computes the basis of betas (omitting 1) used in the additive FFT and its transpose | |||
* | |||
* @param[out] betas Array of size PARAM_M-1 | |||
*/ | |||
static void compute_fft_betas(uint16_t *betas) { | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
betas[i] = 1 << (PARAM_M - 1 - i); | |||
} | |||
} | |||
/** | |||
* @brief Computes the subset sums of the given set | |||
* | |||
* The array subset_sums is such that its ith element is | |||
* the subset sum of the set elements given by the binary form of i. | |||
* | |||
* @param[out] subset_sums Array of size 2^set_size receiving the subset sums | |||
* @param[in] set Array of set_size elements | |||
* @param[in] set_size Size of the array set | |||
*/ | |||
static void compute_subset_sums(uint16_t *subset_sums, const uint16_t *set, size_t set_size) { | |||
subset_sums[0] = 0; | |||
for (size_t i = 0; i < set_size; ++i) { | |||
for (size_t j = 0; j < (((size_t)1) << i); ++j) { | |||
subset_sums[(((size_t)1) << i) + j] = set[i] ^ subset_sums[j]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Transpose of the linear radix conversion | |||
* | |||
* This is a direct transposition of the radix function | |||
* implemented following the process of transposing a linear function as exposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f Array of size a power of 2 | |||
* @param[in] f0 Array half the size of f | |||
* @param[in] f1 Array half the size of f | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the number of coefficients of f | |||
*/ | |||
static void radix_t(uint16_t *f, const uint16_t *f0, const uint16_t *f1, uint32_t m_f) { | |||
switch (m_f) { | |||
case 4: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
f[4] = f[2] ^ f0[2]; | |||
f[5] = f[3] ^ f1[2]; | |||
f[6] = f[4] ^ f0[3] ^ f1[2]; | |||
f[7] = f[3] ^ f0[3] ^ f1[3]; | |||
f[8] = f[4] ^ f0[4]; | |||
f[9] = f[5] ^ f1[4]; | |||
f[10] = f[6] ^ f0[5] ^ f1[4]; | |||
f[11] = f[7] ^ f0[5] ^ f1[4] ^ f1[5]; | |||
f[12] = f[8] ^ f0[5] ^ f0[6] ^ f1[4]; | |||
f[13] = f[7] ^ f[9] ^ f[11] ^ f1[6]; | |||
f[14] = f[6] ^ f0[6] ^ f0[7] ^ f1[6]; | |||
f[15] = f[7] ^ f0[7] ^ f1[7]; | |||
return; | |||
case 3: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
f[4] = f[2] ^ f0[2]; | |||
f[5] = f[3] ^ f1[2]; | |||
f[6] = f[4] ^ f0[3] ^ f1[2]; | |||
f[7] = f[3] ^ f0[3] ^ f1[3]; | |||
return; | |||
case 2: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
return; | |||
case 1: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
return; | |||
default: | |||
; | |||
size_t n = ((size_t)1) << (m_f - 2); | |||
uint16_t Q0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t Q1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t Q[1 << 2 * (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R[1 << 2 * (PARAM_FFT_T - 2)] = {0}; | |||
memcpy(Q0, f0 + n, 2 * n); | |||
memcpy(Q1, f1 + n, 2 * n); | |||
memcpy(R0, f0, 2 * n); | |||
memcpy(R1, f1, 2 * n); | |||
radix_t (Q, Q0, Q1, m_f - 1); | |||
radix_t (R, R0, R1, m_f - 1); | |||
memcpy(f, R, 4 * n); | |||
memcpy(f + 2 * n, R + n, 2 * n); | |||
memcpy(f + 3 * n, Q + n, 2 * n); | |||
for (size_t i = 0; i < n; ++i) { | |||
f[2 * n + i] ^= Q[i]; | |||
f[3 * n + i] ^= f[2 * n + i]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Recursively computes syndromes of family w | |||
* | |||
* This function is a subroutine of the function fft_t | |||
* | |||
* @param[out] f Array receiving the syndromes | |||
* @param[in] w Array storing the family | |||
* @param[in] f_coeffs Length of syndromes vector | |||
* @param[in] m 2^m is the smallest power of 2 greater or equal to the length of family w | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the length of f | |||
* @param[in] betas FFT constants | |||
*/ | |||
static void fft_t_rec(uint16_t *f, const uint16_t *w, size_t f_coeffs, | |||
uint8_t m, uint32_t m_f, const uint16_t *betas) { | |||
size_t k = ((size_t)1) << (m - 1); | |||
uint16_t gammas[PARAM_M - 2] = {0}; | |||
uint16_t deltas[PARAM_M - 2] = {0}; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
uint16_t u[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t f0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)] = {0}; | |||
// Step 1 | |||
if (m_f == 1) { | |||
for (size_t i = 0; i < (((size_t)1) << m); ++i) { | |||
f[0] ^= w[i]; | |||
} | |||
for (size_t j = 0; j < m; ++j) { | |||
for (size_t ki = 0; ki < (((size_t)1) << j); ++ki) { | |||
size_t index = (((size_t)1) << j) + ki; | |||
betas_sums[index] = betas_sums[ki] ^ betas[j]; | |||
f[1] ^= PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(betas_sums[index], w[index]); | |||
} | |||
} | |||
return; | |||
} | |||
// Compute gammas and deltas | |||
for (uint8_t i = 0; i < m - 1; ++i) { | |||
gammas[i] = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(betas[i], PQCLEAN_HQC1922CCA2_LEAKTIME_gf_inverse(betas[m - 1])); | |||
deltas[i] = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_square(gammas[i]) ^ gammas[i]; | |||
} | |||
// Compute gammas subset sums | |||
compute_subset_sums(gammas_sums, gammas, m - 1); | |||
/* Step 6: Compute u and v from w (aka w) | |||
* w[i] = u[i] + G[i].v[i] | |||
* w[k+i] = w[i] + v[i] = u[i] + (G[i]+1).v[i] | |||
* Transpose: | |||
* u[i] = w[i] + w[k+i] | |||
* v[i] = G[i].w[i] + (G[i]+1).w[k+i] = G[i].u[i] + w[k+i] */ | |||
if (f_coeffs <= 3) { // 3-coefficient polynomial f case | |||
// Step 5: Compute f0 from u and f1 from v | |||
f1[1] = 0; | |||
u[0] = w[0] ^ w[k]; | |||
f1[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
f1[0] ^= PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(gammas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
} else { | |||
uint16_t v[1 << (PARAM_M - 2)] = {0}; | |||
u[0] = w[0] ^ w[k]; | |||
v[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
v[i] = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(gammas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
// Step 5: Compute f0 from u and f1 from v | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
fft_t_rec(f1, v, f_coeffs / 2, m - 1, m_f - 1, deltas); | |||
} | |||
// Step 3: Compute g from g0 and g1 | |||
radix_t(f, f0, f1, m_f); | |||
// Step 2: compute f from g | |||
if (betas[m - 1] != 1) { | |||
uint16_t beta_m_pow = 1; | |||
for (size_t i = 1; i < (((size_t)1) << m_f); ++i) { | |||
beta_m_pow = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(beta_m_pow, betas[m - 1]); | |||
f[i] = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(beta_m_pow, f[i]); | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Computes the syndromes f of the family w | |||
* | |||
* Since the syndromes linear map is the transpose of multipoint evaluation, | |||
* it uses exactly the same constants, either hardcoded or precomputed by compute_fft_lut(...). <br> | |||
* This follows directives from Bernstein, Chou and Schwabe given here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f Array of size 2*(PARAM_FFT_T) elements receiving the syndromes | |||
* @param[in] w Array of PARAM_GF_MUL_ORDER+1 elements | |||
* @param[in] f_coeffs Length of syndromes vector f | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_fft_t(uint16_t *f, const uint16_t *w, size_t f_coeffs) { | |||
// Transposed from Gao and Mateer algorithm | |||
uint16_t betas[PARAM_M - 1]; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
uint16_t u[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t deltas[PARAM_M - 1]; | |||
uint16_t f0[1 << (PARAM_FFT_T - 1)]; | |||
uint16_t f1[1 << (PARAM_FFT_T - 1)]; | |||
compute_fft_betas(betas); | |||
compute_subset_sums(betas_sums, betas, PARAM_M - 1); | |||
/* Step 6: Compute u and v from w (aka w) | |||
* | |||
* We had: | |||
* w[i] = u[i] + G[i].v[i] | |||
* w[k+i] = w[i] + v[i] = u[i] + (G[i]+1).v[i] | |||
* Transpose: | |||
* u[i] = w[i] + w[k+i] | |||
* v[i] = G[i].w[i] + (G[i]+1).w[k+i] = G[i].u[i] + w[k+i] */ | |||
u[0] = w[0] ^ w[k]; | |||
v[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
v[i] = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(betas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
// Compute deltas | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
deltas[i] = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_square(betas[i]) ^ betas[i]; | |||
} | |||
// Step 5: Compute f0 from u and f1 from v | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, PARAM_M - 1, PARAM_FFT_T - 1, deltas); | |||
fft_t_rec(f1, v, f_coeffs / 2, PARAM_M - 1, PARAM_FFT_T - 1, deltas); | |||
// Step 3: Compute g from g0 and g1 | |||
radix_t(f, f0, f1, PARAM_FFT_T); | |||
// Step 2: beta_m = 1 so f = g | |||
} | |||
/** | |||
* @brief Computes the radix conversion of a polynomial f in GF(2^m)[x] | |||
* | |||
* Computes f0 and f1 such that f(x) = f0(x^2-x) + x.f1(x^2-x) | |||
* as proposed by Bernstein, Chou and Schwabe: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f0 Array half the size of f | |||
* @param[out] f1 Array half the size of f | |||
* @param[in] f Array of size a power of 2 | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the number of coefficients of f | |||
*/ | |||
static void radix(uint16_t *f0, uint16_t *f1, const uint16_t *f, uint32_t m_f) { | |||
switch (m_f) { | |||
case 4: | |||
f0[4] = f[8] ^ f[12]; | |||
f0[6] = f[12] ^ f[14]; | |||
f0[7] = f[14] ^ f[15]; | |||
f1[5] = f[11] ^ f[13]; | |||
f1[6] = f[13] ^ f[14]; | |||
f1[7] = f[15]; | |||
f0[5] = f[10] ^ f[12] ^ f1[5]; | |||
f1[4] = f[9] ^ f[13] ^ f0[5]; | |||
f0[0] = f[0]; | |||
f1[3] = f[7] ^ f[11] ^ f[15]; | |||
f0[3] = f[6] ^ f[10] ^ f[14] ^ f1[3]; | |||
f0[2] = f[4] ^ f0[4] ^ f0[3] ^ f1[3]; | |||
f1[1] = f[3] ^ f[5] ^ f[9] ^ f[13] ^ f1[3]; | |||
f1[2] = f[3] ^ f1[1] ^ f0[3]; | |||
f0[1] = f[2] ^ f0[2] ^ f1[1]; | |||
f1[0] = f[1] ^ f0[1]; | |||
return; | |||
case 3: | |||
f0[0] = f[0]; | |||
f0[2] = f[4] ^ f[6]; | |||
f0[3] = f[6] ^ f[7]; | |||
f1[1] = f[3] ^ f[5] ^ f[7]; | |||
f1[2] = f[5] ^ f[6]; | |||
f1[3] = f[7]; | |||
f0[1] = f[2] ^ f0[2] ^ f1[1]; | |||
f1[0] = f[1] ^ f0[1]; | |||
return; | |||
case 2: | |||
f0[0] = f[0]; | |||
f0[1] = f[2] ^ f[3]; | |||
f1[0] = f[1] ^ f0[1]; | |||
f1[1] = f[3]; | |||
return; | |||
case 1: | |||
f0[0] = f[0]; | |||
f1[0] = f[1]; | |||
return; | |||
default: | |||
; | |||
size_t n = ((size_t)1) << (m_f - 2); | |||
uint16_t Q[2 * (1 << (PARAM_FFT - 2))]; | |||
uint16_t R[2 * (1 << (PARAM_FFT - 2))]; | |||
uint16_t Q0[1 << (PARAM_FFT - 2)]; | |||
uint16_t Q1[1 << (PARAM_FFT - 2)]; | |||
uint16_t R0[1 << (PARAM_FFT - 2)]; | |||
uint16_t R1[1 << (PARAM_FFT - 2)]; | |||
memcpy(Q, f + 3 * n, 2 * n); | |||
memcpy(Q + n, f + 3 * n, 2 * n); | |||
memcpy(R, f, 4 * n); | |||
for (size_t i = 0; i < n; ++i) { | |||
Q[i] ^= f[2 * n + i]; | |||
R[n + i] ^= Q[i]; | |||
} | |||
radix(Q0, Q1, Q, m_f - 1); | |||
radix(R0, R1, R, m_f - 1); | |||
memcpy(f0, R0, 2 * n); | |||
memcpy(f0 + n, Q0, 2 * n); | |||
memcpy(f1, R1, 2 * n); | |||
memcpy(f1 + n, Q1, 2 * n); | |||
} | |||
} | |||
/** | |||
* @brief Evaluates f at all subset sums of a given set | |||
* | |||
* This function is a subroutine of the function fft. | |||
* | |||
* @param[out] w Array | |||
* @param[in] f Array | |||
* @param[in] f_coeffs Number of coefficients of f | |||
* @param[in] m Number of betas | |||
* @param[in] m_f Number of coefficients of f (one more than its degree) | |||
* @param[in] betas FFT constants | |||
*/ | |||
static void fft_rec(uint16_t *w, uint16_t *f, size_t f_coeffs, | |||
uint8_t m, uint32_t m_f, const uint16_t *betas) { | |||
uint16_t f0[1 << (PARAM_FFT - 2)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT - 2)] = {0}; | |||
uint16_t gammas[PARAM_M - 2] = {0}; | |||
uint16_t deltas[PARAM_M - 2] = {0}; | |||
size_t k = ((size_t)1) << (m - 1); | |||
uint16_t gammas_sums[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t u[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 2)] = {0}; | |||
// Step 1 | |||
if (m_f == 1) { | |||
uint16_t tmp[PARAM_M - (PARAM_FFT - 1)]; | |||
for (size_t i = 0; i < m; ++i) { | |||
tmp[i] = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(betas[i], f[1]); | |||
} | |||
w[0] = f[0]; | |||
for (size_t j = 0; j < m; ++j) { | |||
for (size_t ki = 0; ki < (((size_t)1) << j); ++ki) { | |||
w[(((size_t)1) << j) + ki] = w[ki] ^ tmp[j]; | |||
} | |||
} | |||
return; | |||
} | |||
// Step 2: compute g | |||
if (betas[m - 1] != 1) { | |||
uint16_t beta_m_pow = 1; | |||
for (size_t i = 1; i < (((size_t)1) << m_f); ++i) { | |||
beta_m_pow = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(beta_m_pow, betas[m - 1]); | |||
f[i] = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(beta_m_pow, f[i]); | |||
} | |||
} | |||
// Step 3 | |||
radix(f0, f1, f, m_f); | |||
// Step 4: compute gammas and deltas | |||
for (uint8_t i = 0; i < m - 1; ++i) { | |||
gammas[i] = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(betas[i], PQCLEAN_HQC1922CCA2_LEAKTIME_gf_inverse(betas[m - 1])); | |||
deltas[i] = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_square(gammas[i]) ^ gammas[i]; | |||
} | |||
// Compute gammas sums | |||
compute_subset_sums(gammas_sums, gammas, m - 1); | |||
// Step 5 | |||
fft_rec(u, f0, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
if (f_coeffs <= 3) { // 3-coefficient polynomial f case: f1 is constant | |||
w[0] = u[0]; | |||
w[k] = u[0] ^ f1[0]; | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(gammas_sums[i], f1[0]); | |||
w[k + i] = w[i] ^ f1[0]; | |||
} | |||
} else { | |||
fft_rec(v, f1, f_coeffs / 2, m - 1, m_f - 1, deltas); | |||
// Step 6 | |||
memcpy(w + k, v, 2 * k); | |||
w[0] = u[0]; | |||
w[k] ^= u[0]; | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(gammas_sums[i], v[i]); | |||
w[k + i] ^= w[i]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Evaluates f on all fields elements using an additive FFT algorithm | |||
* | |||
* f_coeffs is the number of coefficients of f (one less than its degree). <br> | |||
* The FFT proceeds recursively to evaluate f at all subset sums of a basis B. <br> | |||
* This implementation is based on the paper from Gao and Mateer: <br> | |||
* Shuhong Gao and Todd Mateer, Additive Fast Fourier Transforms over Finite Fields, | |||
* IEEE Transactions on Information Theory 56 (2010), 6265--6272. | |||
* http://www.math.clemson.edu/~sgao/papers/GM10.pdf <br> | |||
* and includes improvements proposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf <br> | |||
* Constants betas, gammas and deltas involved in the algorithm are either hardcoded or precomputed | |||
* by the subroutine compute_fft_lut(...). <br> | |||
* Note that on this first call (as opposed to the recursive calls to fft_rec), gammas are equal to betas, | |||
* meaning the first gammas subset sums are actually the subset sums of betas (except 1). <br> | |||
* Also note that f is altered during computation (twisted at each level). | |||
* | |||
* @param[out] w Array | |||
* @param[in] f Array of 2^PARAM_FFT elements | |||
* @param[in] f_coeffs Number coefficients of f (i.e. deg(f)+1) | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_fft(uint16_t *w, const uint16_t *f, size_t f_coeffs) { | |||
uint16_t betas[PARAM_M - 1] = {0}; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t f0[1 << (PARAM_FFT - 1)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT - 1)] = {0}; | |||
uint16_t deltas[PARAM_M - 1]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
uint16_t u[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 1)] = {0}; | |||
// Follows Gao and Mateer algorithm | |||
compute_fft_betas(betas); | |||
// Step 1: PARAM_FFT > 1, nothing to do | |||
// Compute gammas sums | |||
compute_subset_sums(betas_sums, betas, PARAM_M - 1); | |||
// Step 2: beta_m = 1, nothing to do | |||
// Step 3 | |||
radix(f0, f1, f, PARAM_FFT); | |||
// Step 4: Compute deltas | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
deltas[i] = PQCLEAN_HQC1922CCA2_LEAKTIME_gf_square(betas[i]) ^ betas[i]; | |||
} | |||
// Step 5 | |||
fft_rec(u, f0, (f_coeffs + 1) / 2, PARAM_M - 1, PARAM_FFT - 1, deltas); | |||
fft_rec(v, f1, f_coeffs / 2, PARAM_M - 1, PARAM_FFT - 1, deltas); | |||
// Step 6, 7 and error polynomial computation | |||
memcpy(w + k, v, 2 * k); | |||
// Check if 0 is root | |||
w[0] = u[0]; | |||
// Check if 1 is root | |||
w[k] ^= u[0]; | |||
// Find other roots | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(betas_sums[i], v[i]); | |||
w[k + i] ^= w[i]; | |||
} | |||
} | |||
/** | |||
* @brief Arranges the received word vector in a form w such that applying the additive FFT transpose to w yields the BCH syndromes of the received word vector. | |||
* | |||
* Since the received word vector gives coefficients of the primitive element alpha, we twist accordingly. <br> | |||
* Furthermore, the additive FFT transpose needs elements indexed by their decomposition on the chosen basis, | |||
* so we apply the adequate permutation. | |||
* | |||
* @param[out] w Array of size 2^PARAM_M | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(uint16_t *w, const uint8_t *vector) { | |||
uint16_t r[1 << PARAM_M]; | |||
uint16_t gammas[PARAM_M - 1]; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
// Unpack the received word vector into array r | |||
size_t i; | |||
for (i = 0; i < VEC_N1_SIZE_BYTES - (PARAM_N1 % 8 != 0); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
r[8 * i + j] = (vector[i] >> j) & 1; | |||
} | |||
} | |||
// Last byte | |||
for (size_t j = 0; j < PARAM_N1 % 8; ++j) { | |||
r[8 * i + j] = (vector[i] >> j) & 1; | |||
} | |||
// Complete r with zeros | |||
memset(r + PARAM_N1, 0, 2 * ((1 << PARAM_M) - PARAM_N1)); | |||
compute_fft_betas(gammas); | |||
compute_subset_sums(gammas_sums, gammas, PARAM_M - 1); | |||
// Twist and permute r adequately to obtain w | |||
w[0] = 0; | |||
w[k] = -r[0] & 1; | |||
for (i = 1; i < k; ++i) { | |||
w[i] = -r[PQCLEAN_HQC1922CCA2_LEAKTIME_gf_log(gammas_sums[i])] & gammas_sums[i]; | |||
w[k + i] = -r[PQCLEAN_HQC1922CCA2_LEAKTIME_gf_log(gammas_sums[i] ^ 1)] & (gammas_sums[i] ^ 1); | |||
} | |||
} | |||
/** | |||
* @brief Retrieves the error polynomial error from the evaluations w of the ELP (Error Locator Polynomial) on all field elements. | |||
* | |||
* @param[out] error Array of size VEC_N1_SIZE_BYTES | |||
* @param[in] w Array of size 2^PARAM_M | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_fft_retrieve_bch_error_poly(uint8_t *error, const uint16_t *w) { | |||
uint16_t gammas[PARAM_M - 1]; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
size_t index = PARAM_GF_MUL_ORDER; | |||
compute_fft_betas(gammas); | |||
compute_subset_sums(gammas_sums, gammas, PARAM_M - 1); | |||
error[0] ^= 1 ^ ((uint16_t) - w[0] >> 15); | |||
uint8_t bit = 1 ^ ((uint16_t) - w[k] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
for (size_t i = 1; i < k; ++i) { | |||
index = PARAM_GF_MUL_ORDER - PQCLEAN_HQC1922CCA2_LEAKTIME_gf_log(gammas_sums[i]); | |||
bit = 1 ^ ((uint16_t) - w[i] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
index = PARAM_GF_MUL_ORDER - PQCLEAN_HQC1922CCA2_LEAKTIME_gf_log(gammas_sums[i] ^ 1); | |||
bit = 1 ^ ((uint16_t) - w[k + i] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
} | |||
} |
@@ -1,18 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1922CCA2_LEAKTIME_FFT_H | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_FFT_H | |||
/** | |||
* @file fft.h | |||
* Header file of fft.c | |||
*/ | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_fft_t(uint16_t *f, const uint16_t *w, size_t f_coeffs); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(uint16_t *w, const uint8_t *vector); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_fft(uint16_t *w, const uint16_t *f, size_t f_coeffs); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_fft_retrieve_bch_error_poly(uint8_t *error, const uint16_t *w); | |||
#endif |
@@ -1,18 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1922CCA2_LEAKTIME_GF_H | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_GF_H | |||
/** | |||
* @file gf.h | |||
* Header file of gf.c | |||
*/ | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
uint16_t PQCLEAN_HQC1922CCA2_LEAKTIME_gf_log(uint16_t elt); | |||
uint16_t PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mul(uint16_t a, uint16_t b); | |||
uint16_t PQCLEAN_HQC1922CCA2_LEAKTIME_gf_square(uint16_t a); | |||
uint16_t PQCLEAN_HQC1922CCA2_LEAKTIME_gf_inverse(uint16_t a); | |||
uint16_t PQCLEAN_HQC1922CCA2_LEAKTIME_gf_mod(uint16_t i); | |||
#endif |
@@ -1,123 +0,0 @@ | |||
/** | |||
* \file gf2x.c | |||
* \brief Implementation of multiplication of two polynomials | |||
*/ | |||
#include "gf2x.h" | |||
#include "parameters.h" | |||
#include "util.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
#define WORD_TYPE uint64_t | |||
#define WORD_TYPE_BITS (sizeof(WORD_TYPE) * 8) | |||
#define UTILS_VECTOR_ARRAY_SIZE CEIL_DIVIDE(PARAM_N, WORD_TYPE_BITS) | |||
static int vect_mul_precompute_rows(WORD_TYPE *o, const WORD_TYPE *v); | |||
/** | |||
* @brief A subroutine used in the function sparse_dense_mul() | |||
* | |||
* @param[out] o Pointer to an array | |||
* @param[in] v Pointer to an array | |||
* @return 0 if precomputation is successful, -1 otherwise | |||
*/ | |||
static int vect_mul_precompute_rows(WORD_TYPE *o, const WORD_TYPE *v) { | |||
int8_t var; | |||
for (size_t i = 0; i < PARAM_N; ++i) { | |||
var = 0; | |||
// All the bits that we need are in the same block | |||
if (((i % WORD_TYPE_BITS) == 0) && (i != PARAM_N - (PARAM_N % WORD_TYPE_BITS))) { | |||
var = 1; | |||
} | |||
// Cases where the bits are in before the last block, the last block and the first block | |||
if (i > PARAM_N - WORD_TYPE_BITS) { | |||
if (i >= PARAM_N - (PARAM_N % WORD_TYPE_BITS)) { | |||
var = 2; | |||
} else { | |||
var = 3; | |||
} | |||
} | |||
switch (var) { | |||
case 0: | |||
// Take bits in the last block and the first one | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[(i / WORD_TYPE_BITS) + 1] << (WORD_TYPE_BITS - (i % WORD_TYPE_BITS)); | |||
break; | |||
case 1: | |||
o[i] = v[i / WORD_TYPE_BITS]; | |||
break; | |||
case 2: | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[0] << ((PARAM_N - i) % WORD_TYPE_BITS); | |||
break; | |||
case 3: | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[(i / WORD_TYPE_BITS) + 1] << (WORD_TYPE_BITS - (i % WORD_TYPE_BITS)); | |||
o[i] += v[0] << ((WORD_TYPE_BITS - i + (PARAM_N % WORD_TYPE_BITS)) % WORD_TYPE_BITS); | |||
break; | |||
default: | |||
return -1; | |||
} | |||
} | |||
return 0; | |||
} | |||
/** | |||
* @brief Multiplies two vectors | |||
* | |||
* This function multiplies two vectors: a sparse vector of Hamming weight equal to <b>weight</b> and a dense (random) vector. | |||
* The vector <b>a1</b> is the sparse vector and <b>a2</b> is the dense vector. | |||
* We notice that the idea is explained using vector of 32 bits elements instead of 64 (the algorithm works in booth cases). | |||
* | |||
* @param[out] o Pointer to a vector that is the result of the multiplication | |||
* @param[in] a1 Pointer to the sparse vector stored by position | |||
* @param[in] a2 Pointer to the dense vector | |||
* @param[in] weight Integer that is the weight of the sparse vector | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_mul(uint8_t *o, const uint32_t *a1, const uint8_t *a2, uint16_t weight) { | |||
WORD_TYPE v1[UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
WORD_TYPE res[UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
WORD_TYPE precomputation_array [PARAM_N] = {0}; | |||
WORD_TYPE row [UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
uint32_t index; | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_load8_arr(v1, UTILS_VECTOR_ARRAY_SIZE, a2, VEC_N_SIZE_BYTES); | |||
vect_mul_precompute_rows(precomputation_array, v1); | |||
for (size_t i = 0; i < weight; ++i) { | |||
int32_t k = UTILS_VECTOR_ARRAY_SIZE; | |||
for (size_t j = 0; j < UTILS_VECTOR_ARRAY_SIZE - 1; ++j) { | |||
index = WORD_TYPE_BITS * (uint32_t)j - a1[i]; | |||
if (index > PARAM_N) { | |||
index += PARAM_N; | |||
} | |||
row[j] = precomputation_array[index]; | |||
} | |||
index = WORD_TYPE_BITS * (UTILS_VECTOR_ARRAY_SIZE - 1) - a1[i]; | |||
row[UTILS_VECTOR_ARRAY_SIZE - 1] = precomputation_array[(index < PARAM_N ? index : index + PARAM_N)] & BITMASK(PARAM_N, WORD_TYPE_BITS); | |||
while (k--) { | |||
res[k] ^= row[k]; | |||
} | |||
} | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_store8_arr(o, VEC_N_SIZE_BYTES, res, UTILS_VECTOR_ARRAY_SIZE); | |||
} |
@@ -1,13 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1922CCA2_LEAKTIME_GF2X_H | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_GF2X_H | |||
/** | |||
* @file gf2x.h | |||
* @brief Header file for gf2x.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_mul(uint8_t *o, const uint32_t *a1, const uint8_t *a2, uint16_t weight); | |||
#endif |
@@ -1,135 +0,0 @@ | |||
/** | |||
* @file hqc.c | |||
* @brief Implementation of hqc.h | |||
*/ | |||
#include "gf2x.h" | |||
#include "hqc.h" | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "randombytes.h" | |||
#include "tensor.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
/** | |||
* @brief Keygen of the HQC_PKE IND_CPA scheme | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the <b>seed</b> used to generate the vector <b>h</b>. | |||
* | |||
* The secret key is composed of the <b>seed</b> used to generate vectors <b>x</b> and <b>y</b>. | |||
* As a technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[out] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_pke_keygen(uint8_t *pk, uint8_t *sk) { | |||
AES_XOF_struct sk_seedexpander; | |||
AES_XOF_struct pk_seedexpander; | |||
uint8_t sk_seed[SEED_BYTES] = {0}; | |||
uint8_t pk_seed[SEED_BYTES] = {0}; | |||
uint8_t x[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t y[PARAM_OMEGA] = {0}; | |||
uint8_t h[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t s[VEC_N_SIZE_BYTES] = {0}; | |||
// Create seed_expanders for public key and secret key | |||
randombytes(sk_seed, SEED_BYTES); | |||
seedexpander_init(&sk_seedexpander, sk_seed, sk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
randombytes(pk_seed, SEED_BYTES); | |||
seedexpander_init(&pk_seedexpander, pk_seed, pk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
// Compute secret key | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_fixed_weight(&sk_seedexpander, x, PARAM_OMEGA); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&sk_seedexpander, y, PARAM_OMEGA); | |||
// Compute public key | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random(&pk_seedexpander, h); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_mul(s, y, h, PARAM_OMEGA); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_add(s, x, s, VEC_N_SIZE_BYTES); | |||
// Parse keys to string | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_public_key_to_string(pk, pk_seed, s); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_secret_key_to_string(sk, sk_seed, pk); | |||
} | |||
/** | |||
* @brief Encryption of the HQC_PKE IND_CPA scheme | |||
* | |||
* The cihertext is composed of vectors <b>u</b> and <b>v</b>. | |||
* | |||
* @param[out] u Vector u (first part of the ciphertext) | |||
* @param[out] v Vector v (second part of the ciphertext) | |||
* @param[in] m Vector representing the message to encrypt | |||
* @param[in] theta Seed used to derive randomness required for encryption | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_pke_encrypt(uint8_t *u, uint8_t *v, const uint8_t *m, const uint8_t *theta, const uint8_t *pk) { | |||
AES_XOF_struct seedexpander; | |||
uint8_t h[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t s[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t r1[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t r2[PARAM_OMEGA_R] = {0}; | |||
uint8_t e[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp1[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp2[VEC_N_SIZE_BYTES] = {0}; | |||
// Create seed_expander from theta | |||
seedexpander_init(&seedexpander, theta, theta + 32, SEEDEXPANDER_MAX_LENGTH); | |||
// Retrieve h and s from public key | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_public_key_from_string(h, s, pk); | |||
// Generate r1, r2 and e | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_fixed_weight(&seedexpander, r1, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&seedexpander, r2, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_fixed_weight(&seedexpander, e, PARAM_OMEGA_E); | |||
// Compute u = r1 + r2.h | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_mul(u, r2, h, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_add(u, r1, u, VEC_N_SIZE_BYTES); | |||
// Compute v = m.G by encoding the message | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_tensor_code_encode(v, m); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_resize(tmp1, PARAM_N, v, PARAM_N1N2); | |||
// Compute v = m.G + s.r2 + e | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_mul(tmp2, r2, s, PARAM_OMEGA_R); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_add(tmp2, e, tmp2, VEC_N_SIZE_BYTES); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_add(tmp2, tmp1, tmp2, VEC_N_SIZE_BYTES); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_resize(v, PARAM_N1N2, tmp2, PARAM_N); | |||
} | |||
/** | |||
* @brief Decryption of the HQC_PKE IND_CPA scheme | |||
* | |||
* @param[out] m Vector representing the decrypted message | |||
* @param[in] u Vector u (first part of the ciphertext) | |||
* @param[in] v Vector v (second part of the ciphertext) | |||
* @param[in] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_pke_decrypt(uint8_t *m, const uint8_t *u, const uint8_t *v, const uint8_t *sk) { | |||
uint8_t x[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t y[PARAM_OMEGA] = {0}; | |||
uint8_t pk[PUBLIC_KEY_BYTES] = {0}; | |||
uint8_t tmp1[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp2[VEC_N_SIZE_BYTES] = {0}; | |||
// Retrieve x, y, pk from secret key | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_secret_key_from_string(x, y, pk, sk); | |||
// Compute v - u.y | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_resize(tmp1, PARAM_N, v, PARAM_N1N2); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_mul(tmp2, y, u, PARAM_OMEGA); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_add(tmp2, tmp1, tmp2, VEC_N_SIZE_BYTES); | |||
// Compute m by decoding v - u.y | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_tensor_code_decode(m, tmp2); | |||
} |
@@ -1,15 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1922CCA2_LEAKTIME_HQC_H | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_HQC_H | |||
/** | |||
* @file hqc.h | |||
* @brief Functions of the HQC_PKE IND_CPA scheme | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_pke_keygen(uint8_t *pk, uint8_t *sk); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_pke_encrypt(uint8_t *u, uint8_t *v, const uint8_t *m, const uint8_t *theta, const uint8_t *pk); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_pke_decrypt(uint8_t *m, const uint8_t *u, const uint8_t *v, const uint8_t *sk); | |||
#endif |
@@ -1,154 +0,0 @@ | |||
/** | |||
* @file kem.c | |||
* @brief Implementation of api.h | |||
*/ | |||
#include "api.h" | |||
#include "hqc.h" | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "sha2.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
/** | |||
* @brief Keygen of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b>. | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As a technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[out] sk String containing the secret key | |||
* @returns 0 if keygen is successful | |||
*/ | |||
int PQCLEAN_HQC1922CCA2_LEAKTIME_crypto_kem_keypair(uint8_t *pk, uint8_t *sk) { | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_pke_keygen(pk, sk); | |||
return 0; | |||
} | |||
/** | |||
* @brief Encapsulation of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* @param[out] ct String containing the ciphertext | |||
* @param[out] ss String containing the shared secret | |||
* @param[in] pk String containing the public key | |||
* @returns 0 if encapsulation is successful | |||
*/ | |||
int PQCLEAN_HQC1922CCA2_LEAKTIME_crypto_kem_enc(uint8_t *ct, uint8_t *ss, const uint8_t *pk) { | |||
AES_XOF_struct G_seedexpander; | |||
uint8_t seed_G[VEC_K_SIZE_BYTES]; | |||
uint8_t diversifier_bytes[8] = {0}; | |||
uint8_t m[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t theta[SEED_BYTES] = {0}; | |||
uint8_t u[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d[SHA512_BYTES] = {0}; | |||
uint8_t mc[VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES] = {0}; | |||
// Computing m | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_from_randombytes(m); | |||
// Generating G function | |||
memcpy(seed_G, m, VEC_K_SIZE_BYTES); | |||
seedexpander_init(&G_seedexpander, seed_G, diversifier_bytes, SEEDEXPANDER_MAX_LENGTH); | |||
// Computing theta | |||
seedexpander(&G_seedexpander, theta, SEED_BYTES); | |||
// Encrypting m | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_pke_encrypt(u, v, m, theta, pk); | |||
// Computing d | |||
sha512(d, m, VEC_K_SIZE_BYTES); | |||
// Computing shared secret | |||
memcpy(mc, m, VEC_K_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES, u, VEC_N_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
sha512(ss, mc, VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES); | |||
// Computing ciphertext | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_ciphertext_to_string(ct, u, v, d); | |||
return 0; | |||
} | |||
/** | |||
* @brief Decapsulation of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* @param[out] ss String containing the shared secret | |||
* @param[in] ct String containing the cipĥertext | |||
* @param[in] sk String containing the secret key | |||
* @returns 0 if decapsulation is successful, -1 otherwise | |||
*/ | |||
int PQCLEAN_HQC1922CCA2_LEAKTIME_crypto_kem_dec(uint8_t *ss, const uint8_t *ct, const uint8_t *sk) { | |||
AES_XOF_struct G_seedexpander; | |||
uint8_t seed_G[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t diversifier_bytes[8] = {0}; | |||
uint8_t u[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d[SHA512_BYTES] = {0}; | |||
uint8_t pk[PUBLIC_KEY_BYTES] = {0}; | |||
uint8_t m[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t theta[SEED_BYTES] = {0}; | |||
uint8_t u2[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v2[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d2[SHA512_BYTES] = {0}; | |||
uint8_t mc[VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES] = {0}; | |||
int8_t abort = 0; | |||
// Retrieving u, v and d from ciphertext | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_ciphertext_from_string(u, v, d, ct); | |||
// Retrieving pk from sk | |||
memcpy(pk, sk + SEED_BYTES, PUBLIC_KEY_BYTES); | |||
// Decryting | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_pke_decrypt(m, u, v, sk); | |||
// Generating G function | |||
memcpy(seed_G, m, VEC_K_SIZE_BYTES); | |||
seedexpander_init(&G_seedexpander, seed_G, diversifier_bytes, SEEDEXPANDER_MAX_LENGTH); | |||
// Computing theta | |||
seedexpander(&G_seedexpander, theta, SEED_BYTES); | |||
// Encrypting m' | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_pke_encrypt(u2, v2, m, theta, pk); | |||
// Checking that c = c' and abort otherwise | |||
if (PQCLEAN_HQC1922CCA2_LEAKTIME_vect_compare(u, u2, VEC_N_SIZE_BYTES) != 0 || | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_compare(v, v2, VEC_N1N2_SIZE_BYTES) != 0) { | |||
abort = 1; | |||
} | |||
// Computing d' | |||
sha512(d2, m, VEC_K_SIZE_BYTES); | |||
// Checking that d = d' and abort otherwise | |||
if (memcmp(d, d2, SHA512_BYTES) != 0) { | |||
abort = 1; | |||
} | |||
if (abort == 1) { | |||
memset(ss, 0, SHARED_SECRET_BYTES); | |||
return -1; | |||
} | |||
// Computing shared secret | |||
memcpy(mc, m, VEC_K_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES, u, VEC_N_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
sha512(ss, mc, VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES); | |||
return 0; | |||
} |
@@ -1,109 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1922CCA2_LEAKTIME_HQC_PARAMETERS_H | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_HQC_PARAMETERS_H | |||
/** | |||
* @file parameters.h | |||
* @brief Parameters of the HQC_KEM IND-CCA2 scheme | |||
*/ | |||
#include "api.h" | |||
#define CEIL_DIVIDE(a, b) (((a)/(b)) + ((a) % (b) == 0 ? 0 : 1)) /*!< Divide a by b and ceil the result*/ | |||
#define BITMASK(a, size) ((1ULL << ((a) % (size))) - 1) /*!< Create a mask*/ | |||
/* | |||
#define PARAM_N Define the parameter n of the scheme | |||
#define PARAM_N1 Define the parameter n1 of the scheme (length of BCH code) | |||
#define PARAM_N2 Define the parameter n2 of the scheme (length of the repetition code) | |||
#define PARAM_N1N2 Define the parameter n1 * n2 of the scheme (length of the tensor code) | |||
#define PARAM_OMEGA Define the parameter omega of the scheme | |||
#define PARAM_OMEGA_E Define the parameter omega_e of the scheme | |||
#define PARAM_OMEGA_R Define the parameter omega_r of the scheme | |||
#define PARAM_SECURITY Define the security level corresponding to the chosen parameters | |||
#define PARAM_DFR_EXP Define the decryption failure rate corresponding to the chosen parameters | |||
#define SECRET_KEY_BYTES Define the size of the secret key in bytes | |||
#define PUBLIC_KEY_BYTES Define the size of the public key in bytes | |||
#define SHARED_SECRET_BYTES Define the size of the shared secret in bytes | |||
#define CIPHERTEXT_BYTES Define the size of the ciphertext in bytes | |||
#define UTILS_REJECTION_THRESHOLD Define the rejection threshold used to generate given weight vectors (see vector_set_random_fixed_weight function) | |||
#define VEC_N_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N sized vector in bytes | |||
#define VEC_N1_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N1 sized vector in bytes | |||
#define VEC_N1N2_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N1N2 sized vector in bytes | |||
#define VEC_K_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_K sized vector in bytes | |||
#define PARAM_T Define a threshold for decoding repetition code word (PARAM_T = (PARAM_N2 - 1) / 2) | |||
#define PARAM_DELTA Define the parameter delta of the scheme (correcting capacity of the BCH code) | |||
#define PARAM_M Define a positive integer | |||
#define PARAM_GF_MUL_ORDER Define the size of the multiplicative group of GF(2^m), i.e 2^m -1 | |||
#define PARAM_K Define the size of the information bits of the BCH code | |||
#define PARAM_G Define the size of the generator polynomial of BCH code | |||
#define PARAM_FFT The additive FFT takes a 2^PARAM_FFT polynomial as input | |||
We use the FFT to compute the roots of sigma, whose degree if PARAM_DELTA=60 | |||
The smallest power of 2 greater than 60+1 is 64=2^6 | |||
#define PARAM_FFT_T The additive FFT transpose computes a (2^PARAM_FFT_T)-sized syndrome vector | |||
We want to compute 2*PARAM_DELTA=120 syndromes | |||
The smallest power of 2 greater than 120 is 2^7 | |||
#define PARAM_BCH_POLY Generator polynomial of the BCH code | |||
#define SHA512_BYTES Define the size of SHA512 output in bytes | |||
#define SEED_BYTES Define the size of the seed in bytes | |||
#define SEEDEXPANDER_MAX_LENGTH Define the seed expander max length | |||
*/ | |||
#define PARAM_N 46747 | |||
#define PARAM_N1 766 | |||
#define PARAM_N2 61 | |||
#define PARAM_N1N2 46726 | |||
#define PARAM_OMEGA 101 | |||
#define PARAM_OMEGA_E 117 | |||
#define PARAM_OMEGA_R 117 | |||
#define PARAM_SECURITY 192 | |||
#define PARAM_DFR_EXP 192 | |||
#define SECRET_KEY_BYTES PQCLEAN_HQC1922CCA2_LEAKTIME_CRYPTO_SECRETKEYBYTES | |||
#define PUBLIC_KEY_BYTES PQCLEAN_HQC1922CCA2_LEAKTIME_CRYPTO_PUBLICKEYBYTES | |||
#define SHARED_SECRET_BYTES PQCLEAN_HQC1922CCA2_LEAKTIME_CRYPTO_BYTES | |||
#define CIPHERTEXT_BYTES PQCLEAN_HQC1922CCA2_LEAKTIME_CRYPTO_CIPHERTEXTBYTES | |||
#define UTILS_REJECTION_THRESHOLD 16735426 | |||
#define VEC_K_SIZE_BYTES CEIL_DIVIDE(PARAM_K, 8) | |||
#define VEC_N_SIZE_BYTES CEIL_DIVIDE(PARAM_N, 8) | |||
#define VEC_N1_SIZE_BYTES CEIL_DIVIDE(PARAM_N1, 8) | |||
#define VEC_N1N2_SIZE_BYTES CEIL_DIVIDE(PARAM_N1N2, 8) | |||
#define PARAM_T 30 | |||
#define PARAM_DELTA 57 | |||
#define PARAM_M 10 | |||
#define PARAM_GF_MUL_ORDER 1023 | |||
#define PARAM_K 256 | |||
#define PARAM_G 511 | |||
#define PARAM_FFT 6 | |||
#define PARAM_FFT_T 7 | |||
#define PARAM_BCH_POLY { \ | |||
1,1,0,0,0,0,1,0,0,1,1,0,1,1,0,1,0,1,1,0,0,1,0,0,1,1,1,1,1,1,0,0,1,1,0,1,1, \ | |||
1,1,0,1,1,1,1,0,1,0,0,0,1,0,0,1,1,1,0,1,1,0,1,0,1,1,1,0,1,0,1,0,0,1,0,0,0, \ | |||
0,1,1,1,1,0,1,1,1,1,1,0,0,0,0,1,0,0,1,0,0,1,1,1,0,0,0,1,1,0,0,1,0,1,0,0,0, \ | |||
1,0,0,0,0,1,0,0,0,1,0,1,1,0,0,0,0,1,1,0,0,1,1,0,1,0,1,0,1,0,1,1,1,1,0,1,0, \ | |||
0,1,1,0,1,0,1,1,0,0,1,1,0,1,1,1,1,1,0,1,0,1,1,1,0,1,0,0,0,1,1,0,1,1,1,1,0, \ | |||
1,1,1,1,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,1,1,1,1,0,0,1,1,0,1,0,0,0,0,1,0, \ | |||
0,1,0,0,1,0,1,0,0,1,1,0,1,0,1,1,1,1,1,0,1,1,0,1,0,1,1,1,1,1,1,0,0,0,1,0,1, \ | |||
1,1,1,1,1,0,1,0,1,0,1,1,0,0,0,1,1,0,0,1,1,0,1,1,1,1,1,1,1,0,0,0,1,1,1,1,0, \ | |||
1,0,0,0,1,0,0,1,1,0,1,1,0,0,1,0,1,1,0,1,0,1,0,1,1,0,0,0,0,0,1,1,1,1,1,1,1, \ | |||
1,1,1,0,1,1,0,1,0,1,1,1,1,1,1,1,0,1,1,0,1,1,0,0,0,1,0,0,1,1,1,1,1,0,1,0,1, \ | |||
0,0,0,0,1,0,1,1,1,1,0,1,0,0,0,0,0,1,0,0,1,0,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1, \ | |||
1,0,1,0,0,1,0,0,1,1,0,1,0,0,0,0,0,0,0,0,1,1,0,0,0,1,1,1,0,0,1,1,0,0,0,1,1, \ | |||
0,1,0,0,1,0,0,0,1,0,1,0,1,0,0,0,1,1,1,1,1,0,0,0,1,0,0,1,1,0,1,1,0,0,1,0,1, \ | |||
1,0,1,1,1,0,0,0,0,1,1,0,1,1,1,0,1,0,0,0,0,1,0,0,0,1,0,0,1,1 \ | |||
}; | |||
#define SHA512_BYTES 64 | |||
#define SEED_BYTES 40 | |||
#define SEEDEXPANDER_MAX_LENGTH 4294967295 | |||
#endif |
@@ -1,126 +0,0 @@ | |||
/** | |||
* @file parsing.c | |||
* @brief Functions to parse secret key, public key and ciphertext of the HQC scheme | |||
*/ | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
/** | |||
* @brief Parse a secret key into a string | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] sk String containing the secret key | |||
* @param[in] sk_seed Seed used to generate the secret key | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_secret_key_to_string(uint8_t *sk, const uint8_t *sk_seed, const uint8_t *pk) { | |||
memcpy(sk, sk_seed, SEED_BYTES); | |||
memcpy(sk + SEED_BYTES, pk, PUBLIC_KEY_BYTES); | |||
} | |||
/** | |||
* @brief Parse a secret key from a string | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] x uint8_t representation of vector x | |||
* @param[out] y uint8_t representation of vector y | |||
* @param[out] pk String containing the public key | |||
* @param[in] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_secret_key_from_string(uint8_t *x, uint32_t *y, uint8_t *pk, const uint8_t *sk) { | |||
AES_XOF_struct sk_seedexpander; | |||
uint8_t sk_seed[SEED_BYTES] = {0}; | |||
memcpy(sk_seed, sk, SEED_BYTES); | |||
seedexpander_init(&sk_seedexpander, sk_seed, sk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_fixed_weight(&sk_seedexpander, x, PARAM_OMEGA); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&sk_seedexpander, y, PARAM_OMEGA); | |||
memcpy(pk, sk + SEED_BYTES, PUBLIC_KEY_BYTES); | |||
} | |||
/** | |||
* @brief Parse a public key into a string | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b> | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[in] pk_seed Seed used to generate the public key | |||
* @param[in] s uint8_t representation of vector s | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_public_key_to_string(uint8_t *pk, const uint8_t *pk_seed, const uint8_t *s) { | |||
memcpy(pk, pk_seed, SEED_BYTES); | |||
memcpy(pk + SEED_BYTES, s, VEC_N_SIZE_BYTES); | |||
} | |||
/** | |||
* @brief Parse a public key from a string | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b> | |||
* | |||
* @param[out] h uint8_t representation of vector h | |||
* @param[out] s uint8_t representation of vector s | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_public_key_from_string(uint8_t *h, uint8_t *s, const uint8_t *pk) { | |||
AES_XOF_struct pk_seedexpander; | |||
uint8_t pk_seed[SEED_BYTES] = {0}; | |||
memcpy(pk_seed, pk, SEED_BYTES); | |||
seedexpander_init(&pk_seedexpander, pk_seed, pk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random(&pk_seedexpander, h); | |||
memcpy(s, pk + SEED_BYTES, VEC_N_SIZE_BYTES); | |||
} | |||
/** | |||
* @brief Parse a ciphertext into a string | |||
* | |||
* The ciphertext is composed of vectors <b>u</b>, <b>v</b> and hash <b>d</b>. | |||
* | |||
* @param[out] ct String containing the ciphertext | |||
* @param[in] u uint8_t representation of vector u | |||
* @param[in] v uint8_t representation of vector v | |||
* @param[in] d String containing the hash d | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_ciphertext_to_string(uint8_t *ct, const uint8_t *u, const uint8_t *v, const uint8_t *d) { | |||
memcpy(ct, u, VEC_N_SIZE_BYTES); | |||
memcpy(ct + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
memcpy(ct + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES, d, SHA512_BYTES); | |||
} | |||
/** | |||
* @brief Parse a ciphertext from a string | |||
* | |||
* The ciphertext is composed of vectors <b>u</b>, <b>v</b> and hash <b>d</b>. | |||
* | |||
* @param[out] u uint8_t representation of vector u | |||
* @param[out] v uint8_t representation of vector v | |||
* @param[out] d String containing the hash d | |||
* @param[in] ct String containing the ciphertext | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_ciphertext_from_string(uint8_t *u, uint8_t *v, uint8_t *d, const uint8_t *ct) { | |||
memcpy(u, ct, VEC_N_SIZE_BYTES); | |||
memcpy(v, ct + VEC_N_SIZE_BYTES, VEC_N1N2_SIZE_BYTES); | |||
memcpy(d, ct + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES, SHA512_BYTES); | |||
} |
@@ -1,20 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1922CCA2_LEAKTIME_PARSING_H | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_PARSING_H | |||
/** | |||
* @file parsing.h | |||
* @brief Header file for parsing.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_secret_key_to_string(uint8_t *sk, const uint8_t *sk_seed, const uint8_t *pk); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_secret_key_from_string(uint8_t *x, uint32_t *y, uint8_t *pk, const uint8_t *sk); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_public_key_to_string(uint8_t *pk, const uint8_t *pk_seed, const uint8_t *s); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_public_key_from_string(uint8_t *h, uint8_t *s, const uint8_t *pk); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_ciphertext_to_string(uint8_t *ct, const uint8_t *u, const uint8_t *v, const uint8_t *d); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_hqc_ciphertext_from_string(uint8_t *u, uint8_t *v, uint8_t *d, const uint8_t *ct); | |||
#endif |
@@ -1,100 +0,0 @@ | |||
/** | |||
* @file repetition.c | |||
* @brief Implementation of repetition codes | |||
*/ | |||
#include "parameters.h" | |||
#include "repetition.h" | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
static void array_to_rep_codeword(uint8_t *o, const uint8_t *v); | |||
/** | |||
* @brief Encoding each bit in the message m using the repetition code | |||
* | |||
* For reasons of clarity and comprehensibility, we do the encoding by storing the encoded bits in a String (each bit in an a uint8_t), | |||
* then we parse the obtained string to an compact array using the function array_to_rep_codeword(). | |||
* | |||
* @param[out] em Pointer to an array that is the code word | |||
* @param[in] m Pointer to an array that is the message | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_repetition_code_encode(uint8_t *em, const uint8_t *m) { | |||
uint8_t tmp[PARAM_N1N2] = {0}; | |||
uint8_t bit = 0; | |||
uint32_t index; | |||
for (size_t i = 0; i < (VEC_N1_SIZE_BYTES - 1); ++i) { | |||
for (uint8_t j = 0; j < 8; ++j) { | |||
bit = (m[i] >> j) & 0x01; | |||
index = (8 * (uint32_t)i + j) * PARAM_N2; | |||
for (uint8_t k = 0; k < PARAM_N2; ++k) { | |||
tmp[index + k] = bit; | |||
} | |||
} | |||
} | |||
for (uint8_t j = 0; j < (PARAM_N1 % 8); ++j) { | |||
bit = (m[VEC_N1_SIZE_BYTES - 1] >> j) & 0x01; | |||
index = (8 * (VEC_N1_SIZE_BYTES - 1) + j) * PARAM_N2; | |||
for (uint8_t k = 0; k < PARAM_N2; ++k) { | |||
tmp[index + k] = bit; | |||
} | |||
} | |||
array_to_rep_codeword(em, tmp); | |||
} | |||
/** | |||
* @brief Decoding the code words to a message using the repetition code | |||
* | |||
* We use a majority decoding. In fact we have that PARAM_N2 = 2 * PARAM_T + 1, thus, | |||
* if the Hamming weight of the vector is greater than PARAM_T, the code word is decoded | |||
* to 1 and 0 otherwise. | |||
* | |||
* @param[out] m Pointer to an array that is the message | |||
* @param[in] em Pointer to an array that is the code word | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_repetition_code_decode(uint8_t *m, const uint8_t *em) { | |||
size_t t = 0; // m index | |||
uint8_t k = PARAM_N2; // block counter | |||
uint8_t ones = 0; // number of 1 in the current block | |||
for (size_t i = 0; i < VEC_N1N2_SIZE_BYTES; ++i) { | |||
for (uint8_t j = 0; j < 8; ++j) { | |||
ones += (em[i] >> j) & 0x01; | |||
if (--k) { | |||
continue; | |||
} | |||
m[t / 8] |= (ones > PARAM_T) << t % 8; | |||
++t; | |||
k = PARAM_N2; | |||
ones = 0; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Parse an array to an compact array | |||
* | |||
* @param[out] o Pointer to an array | |||
* @param[in] v Pointer to an array | |||
*/ | |||
static void array_to_rep_codeword(uint8_t *o, const uint8_t *v) { | |||
for (size_t i = 0; i < (VEC_N1N2_SIZE_BYTES - 1); ++i) { | |||
for (uint8_t j = 0; j < 8; ++j) { | |||
o[i] |= v[j + 8 * i] << j; | |||
} | |||
} | |||
for (uint8_t j = 0; j < PARAM_N1N2 % 8; ++j) { | |||
o[VEC_N1N2_SIZE_BYTES - 1] |= (v[j + 8 * (VEC_N1N2_SIZE_BYTES - 1)]) << j; | |||
} | |||
} |
@@ -1,14 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1922CCA2_LEAKTIME_REPETITION_H | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_REPETITION_H | |||
/** | |||
* @file repetition.h | |||
* @brief Header file for repetition.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_repetition_code_encode(uint8_t *em, const uint8_t *m); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_repetition_code_decode(uint8_t *m, const uint8_t *em); | |||
#endif |
@@ -1,42 +0,0 @@ | |||
/** | |||
* @file tensor.c | |||
* @brief Implementation of tensor code | |||
*/ | |||
#include "bch.h" | |||
#include "parameters.h" | |||
#include "repetition.h" | |||
#include "tensor.h" | |||
#include <stdint.h> | |||
/** | |||
* @brief Encoding the message m to a code word em using the tensor code | |||
* | |||
* First we encode the message using the BCH code, then with the repetition code to obtain | |||
* a tensor code word. | |||
* | |||
* @param[out] em Pointer to an array that is the tensor code word | |||
* @param[in] m Pointer to an array that is the message | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_tensor_code_encode(uint8_t *em, const uint8_t *m) { | |||
uint8_t tmp[VEC_N1_SIZE_BYTES] = {0}; | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_bch_code_encode(tmp, m); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_repetition_code_encode(em, tmp); | |||
} | |||
/** | |||
* @brief Decoding the code word em to a message m using the tensor code | |||
* | |||
* @param[out] m Pointer to an array that is the message | |||
* @param[in] em Pointer to an array that is the code word | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_tensor_code_decode(uint8_t *m, const uint8_t *em) { | |||
uint8_t tmp[VEC_N1_SIZE_BYTES] = {0}; | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_repetition_code_decode(tmp, em); | |||
PQCLEAN_HQC1922CCA2_LEAKTIME_bch_code_decode(m, tmp); | |||
} |
@@ -1,14 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1922CCA2_LEAKTIME_TENSOR_H | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_TENSOR_H | |||
/** | |||
* @file tensor.h | |||
* @brief Header file for tensor.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_tensor_code_encode(uint8_t *em, const uint8_t *m); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_tensor_code_decode(uint8_t *m, const uint8_t *em); | |||
#endif |
@@ -1,69 +0,0 @@ | |||
#include "util.h" | |||
#include "stddef.h" | |||
#include "assert.h" | |||
/* These functions should help with endianness-safe conversions | |||
* | |||
* load8 and store8 are copied from the McEliece implementations, | |||
* which are in the public domain. | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_store8(unsigned char *out, uint64_t in) { | |||
out[0] = (in >> 0x00) & 0xFF; | |||
out[1] = (in >> 0x08) & 0xFF; | |||
out[2] = (in >> 0x10) & 0xFF; | |||
out[3] = (in >> 0x18) & 0xFF; | |||
out[4] = (in >> 0x20) & 0xFF; | |||
out[5] = (in >> 0x28) & 0xFF; | |||
out[6] = (in >> 0x30) & 0xFF; | |||
out[7] = (in >> 0x38) & 0xFF; | |||
} | |||
uint64_t PQCLEAN_HQC1922CCA2_LEAKTIME_load8(const unsigned char *in) { | |||
uint64_t ret = in[7]; | |||
for (int8_t i = 6; i >= 0; i--) { | |||
ret <<= 8; | |||
ret |= in[i]; | |||
} | |||
return ret; | |||
} | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_load8_arr(uint64_t *out64, size_t outlen, const uint8_t *in8, size_t inlen) { | |||
size_t index_in = 0; | |||
size_t index_out = 0; | |||
// first copy by 8 bytes | |||
if (inlen >= 8 && outlen >= 1) { | |||
while (index_out < outlen && index_in + 8 <= inlen) { | |||
out64[index_out] = PQCLEAN_HQC1922CCA2_LEAKTIME_load8(in8 + index_in); | |||
index_in += 8; | |||
index_out += 1; | |||
} | |||
} | |||
// we now need to do the last 7 bytes if necessary | |||
if (index_in >= inlen || index_out >= outlen) { | |||
return; | |||
} | |||
out64[index_out] = in8[inlen - 1]; | |||
for (int8_t i = (int8_t)(inlen - index_in) - 2; i >= 0; i--) { | |||
out64[index_out] <<= 8; | |||
out64[index_out] |= in8[index_in + i]; | |||
} | |||
} | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_store8_arr(uint8_t *out8, size_t outlen, const uint64_t *in64, size_t inlen) { | |||
for (size_t index_out = 0, index_in = 0; index_out < outlen && index_in < inlen;) { | |||
out8[index_out] = (in64[index_in] >> ((index_out % 8) * 8)) & 0xFF; | |||
index_out++; | |||
if (index_out % 8 == 0) { | |||
index_in++; | |||
} | |||
} | |||
} |
@@ -1,9 +0,0 @@ | |||
/* These functions should help with endianness-safe conversions */ | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_store8(unsigned char *out, uint64_t in); | |||
uint64_t PQCLEAN_HQC1922CCA2_LEAKTIME_load8(const unsigned char *in); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_load8_arr(uint64_t *out64, size_t outlen, const uint8_t *in8, size_t inlen); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_store8_arr(uint8_t *out8, size_t outlen, const uint64_t *in64, size_t inlen); |
@@ -1,224 +0,0 @@ | |||
/** | |||
* @file vector.c | |||
* @brief Implementation of vectors sampling and some utilities for the HQC scheme | |||
*/ | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "randombytes.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
/** | |||
* @brief Generates a vector of a given Hamming weight | |||
* | |||
* This function generates uniformly at random a binary vector of a Hamming weight equal to the parameter <b>weight</b>. The vector | |||
* is stored by position. | |||
* To generate the vector we have to sample uniformly at random values in the interval [0, PARAM_N -1]. Suppose the PARAM_N is equal to \f$ 70853 \f$, to select a position \f$ r\f$ the function works as follow: | |||
* 1. It makes a call to the seedexpander function to obtain a random number \f$ x\f$ in \f$ [0, 2^{24}[ \f$. | |||
* 2. Let \f$ t = \lfloor {2^{24} \over 70853} \rfloor \times 70853\f$ | |||
* 3. If \f$ x \geq t\f$, go to 1 | |||
* 4. It return \f$ r = x \mod 70853\f$ | |||
* | |||
* The parameter \f$ t \f$ is precomputed and it's denoted by UTILS_REJECTION_THRESHOLD (see the file parameters.h). | |||
* | |||
* @param[in] v Pointer to an array | |||
* @param[in] weight Integer that is the Hamming weight | |||
* @param[in] ctx Pointer to the context of the seed expander | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(AES_XOF_struct *ctx, uint32_t *v, uint16_t weight) { | |||
size_t random_bytes_size = 3 * weight; | |||
uint8_t rand_bytes[3 * PARAM_OMEGA_R] = {0}; // weight is expected to be <= PARAM_OMEGA_R | |||
uint32_t random_data = 0; | |||
uint8_t exist = 0; | |||
size_t j = 0; | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
for (uint32_t i = 0; i < weight; ++i) { | |||
exist = 0; | |||
do { | |||
if (j == random_bytes_size) { | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
j = 0; | |||
} | |||
random_data = ((uint32_t) rand_bytes[j++]) << 16; | |||
random_data |= ((uint32_t) rand_bytes[j++]) << 8; | |||
random_data |= rand_bytes[j++]; | |||
} while (random_data >= UTILS_REJECTION_THRESHOLD); | |||
random_data = random_data % PARAM_N; | |||
for (uint32_t k = 0; k < i; k++) { | |||
if (v[k] == random_data) { | |||
exist = 1; | |||
} | |||
} | |||
if (exist == 1) { | |||
i--; | |||
} else { | |||
v[i] = random_data; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Generates a vector of a given Hamming weight | |||
* | |||
* This function generates uniformly at random a binary vector of a Hamming weight equal to the parameter <b>weight</b>. | |||
* To generate the vector we have to sample uniformly at random values in the interval [0, PARAM_N -1]. Suppose the PARAM_N is equal to \f$ 70853 \f$, to select a position \f$ r\f$ the function works as follow: | |||
* 1. It makes a call to the seedexpander function to obtain a random number \f$ x\f$ in \f$ [0, 2^{24}[ \f$. | |||
* 2. Let \f$ t = \lfloor {2^{24} \over 70853} \rfloor \times 70853\f$ | |||
* 3. If \f$ x \geq t\f$, go to 1 | |||
* 4. It return \f$ r = x \mod 70853\f$ | |||
* | |||
* The parameter \f$ t \f$ is precomputed and it's denoted by UTILS_REJECTION_THRESHOLD (see the file parameters.h). | |||
* | |||
* @param[in] v Pointer to an array | |||
* @param[in] weight Integer that is the Hamming weight | |||
* @param[in] ctx Pointer to the context of the seed expander | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_fixed_weight(AES_XOF_struct *ctx, uint8_t *v, uint16_t weight) { | |||
size_t random_bytes_size = 3 * weight; | |||
uint8_t rand_bytes[3 * PARAM_OMEGA_R] = {0}; // weight is expected to be <= PARAM_OMEGA_R | |||
uint32_t random_data = 0; | |||
uint32_t tmp[PARAM_OMEGA_R] = {0}; | |||
uint8_t exist = 0; | |||
size_t j = 0; | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
for (uint32_t i = 0; i < weight; ++i) { | |||
exist = 0; | |||
do { | |||
if (j == random_bytes_size) { | |||
seedexpander(ctx, rand_bytes, random_bytes_size); | |||
j = 0; | |||
} | |||
random_data = ((uint32_t) rand_bytes[j++]) << 16; | |||
random_data |= ((uint32_t) rand_bytes[j++]) << 8; | |||
random_data |= rand_bytes[j++]; | |||
} while (random_data >= UTILS_REJECTION_THRESHOLD); | |||
random_data = random_data % PARAM_N; | |||
for (uint32_t k = 0; k < i; k++) { | |||
if (tmp[k] == random_data) { | |||
exist = 1; | |||
} | |||
} | |||
if (exist == 1) { | |||
i--; | |||
} else { | |||
tmp[i] = random_data; | |||
} | |||
} | |||
for (uint16_t i = 0; i < weight; ++i) { | |||
int32_t index = tmp[i] / 8; | |||
int32_t pos = tmp[i] % 8; | |||
v[index] |= 1 << pos; | |||
} | |||
} | |||
/** | |||
* @brief Generates a random vector of dimension <b>PARAM_N</b> | |||
* | |||
* This function generates a random binary vector of dimension <b>PARAM_N</b>. It generates a random | |||
* array of bytes using the seedexpander function, and drop the extra bits using a mask. | |||
* | |||
* @param[in] v Pointer to an array | |||
* @param[in] ctx Pointer to the context of the seed expander | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random(AES_XOF_struct *ctx, uint8_t *v) { | |||
uint8_t rand_bytes[VEC_N_SIZE_BYTES] = {0}; | |||
seedexpander(ctx, rand_bytes, VEC_N_SIZE_BYTES); | |||
memcpy(v, rand_bytes, VEC_N_SIZE_BYTES); | |||
v[VEC_N_SIZE_BYTES - 1] &= BITMASK(PARAM_N, 8); | |||
} | |||
/** | |||
* @brief Generates a random vector | |||
* | |||
* This function generates a random binary vector. It uses the the randombytes function. | |||
* | |||
* @param[in] v Pointer to an array | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_from_randombytes(uint8_t *v) { | |||
uint8_t rand_bytes [VEC_K_SIZE_BYTES] = {0}; | |||
randombytes(rand_bytes, VEC_K_SIZE_BYTES); | |||
memcpy(v, rand_bytes, VEC_K_SIZE_BYTES); | |||
} | |||
/** | |||
* @brief Adds two vectors | |||
* | |||
* @param[out] o Pointer to an array that is the result | |||
* @param[in] v1 Pointer to an array that is the first vector | |||
* @param[in] v2 Pointer to an array that is the second vector | |||
* @param[in] size Integer that is the size of the vectors | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_add(uint8_t *o, const uint8_t *v1, const uint8_t *v2, uint32_t size) { | |||
for (uint32_t i = 0; i < size; ++i) { | |||
o[i] = v1[i] ^ v2[i]; | |||
} | |||
} | |||
/** | |||
* @brief Compares two vectors | |||
* | |||
* @param[in] v1 Pointer to an array that is first vector | |||
* @param[in] v2 Pointer to an array that is second vector | |||
* @param[in] size Integer that is the size of the vectors | |||
* @returns 0 if the vectors are equals and a negative/psotive value otherwise | |||
*/ | |||
int PQCLEAN_HQC1922CCA2_LEAKTIME_vect_compare(const uint8_t *v1, const uint8_t *v2, uint32_t size) { | |||
return memcmp(v1, v2, size); | |||
} | |||
/** | |||
* @brief Resize a vector so that it contains <b>size_o</b> bits | |||
* | |||
* @param[out] o Pointer to the output vector | |||
* @param[in] size_o Integer that is the size of the output vector in bits | |||
* @param[in] v Pointer to the input vector | |||
* @param[in] size_v Integer that is the size of the input vector in bits | |||
*/ | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_resize(uint8_t *o, uint32_t size_o, const uint8_t *v, uint32_t size_v) { | |||
if (size_o < size_v) { | |||
uint8_t mask = 0x7F; | |||
int8_t val = 8 - (size_o % 8); | |||
memcpy(o, v, VEC_N1N2_SIZE_BYTES); | |||
for (int8_t i = 0; i < val; ++i) { | |||
o[VEC_N1N2_SIZE_BYTES - 1] &= (mask >> i); | |||
} | |||
} else { | |||
memcpy(o, v, CEIL_DIVIDE(size_v, 8)); | |||
} | |||
} |
@@ -1,22 +0,0 @@ | |||
#ifndef PQCLEAN_HQC1922CCA2_LEAKTIME_VECTOR_H | |||
#define PQCLEAN_HQC1922CCA2_LEAKTIME_VECTOR_H | |||
/** | |||
* @file vector.h | |||
* @brief Header file for vector.c | |||
*/ | |||
#include "nistseedexpander.h" | |||
#include <stdint.h> | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(AES_XOF_struct *ctx, uint32_t *v, uint16_t weight); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_fixed_weight(AES_XOF_struct *ctx, uint8_t *v, uint16_t weight); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random(AES_XOF_struct *ctx, uint8_t *v); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_set_random_from_randombytes(uint8_t *v); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_add(uint8_t *o, const uint8_t *v1, const uint8_t *v2, uint32_t size); | |||
int PQCLEAN_HQC1922CCA2_LEAKTIME_vect_compare(const uint8_t *v1, const uint8_t *v2, uint32_t size); | |||
void PQCLEAN_HQC1922CCA2_LEAKTIME_vect_resize(uint8_t *o, uint32_t size_o, const uint8_t *v, uint32_t size_v); | |||
#endif |
@@ -1,23 +0,0 @@ | |||
name: HQC_256_1_CCA2 | |||
type: kem | |||
claimed-nist-level: 5 | |||
claimed-security: IND-CCA2 | |||
length-public-key: 7989 | |||
length-ciphertext: 15961 | |||
length-secret-key: 8029 | |||
length-shared-secret: 64 | |||
nistkat-sha256: 339bd96be8b2d6bfb12315550b16827c612b41ab7aa4585ded55d2bf87410968 | |||
principal-submitters: | |||
- Carlos Aguilar Melchor | |||
- Nicolas Aragon | |||
- Slim Bettaieb | |||
- Loïc Bidoux | |||
- Olivier Blazy | |||
- Jean-Christophe Deneuville | |||
- Philippe Gaborit | |||
- Edoardo Persichetti | |||
- Gilles Zémor | |||
auxiliary-submitters: [] | |||
implementations: | |||
- name: leaktime | |||
version: https://pqc-hqc.org/doc/hqc-reference-implementation_2019-08-24.zip |
@@ -1 +0,0 @@ | |||
Public domain |
@@ -1,19 +0,0 @@ | |||
# This Makefile can be used with GNU Make or BSD Make | |||
LIB=libhqc-256-1-cca2_leaktime.a | |||
HEADERS=api.h bch.h fft.h gf.h gf2x.h hqc.h parameters.h parsing.h repetition.h tensor.h vector.h util.h | |||
OBJECTS=bch.o fft.o gf.o gf2x.o hqc.o kem.o parsing.o repetition.o tensor.o vector.o util.o | |||
CFLAGS=-O3 -Wall -Wextra -Wpedantic -Wvla -Werror -Wmissing-prototypes -Wredundant-decls -std=c99 -I../../../common $(EXTRAFLAGS) | |||
all: $(LIB) | |||
%.o: %.c $(HEADERS) | |||
$(CC) $(CFLAGS) -c -o $@ $< | |||
$(LIB): $(OBJECTS) | |||
$(AR) -r $@ $(OBJECTS) | |||
clean: | |||
$(RM) $(OBJECTS) | |||
$(RM) $(LIB) |
@@ -1,23 +0,0 @@ | |||
# This Makefile can be used with Microsoft Visual Studio's nmake using the command: | |||
# nmake /f Makefile.Microsoft_nmake | |||
LIBRARY=libhqc-256-1-cca2_leaktime.lib | |||
OBJECTS=bch.obj fft.obj gf.obj gf2x.obj hqc.obj kem.obj parsing.obj repetition.obj tensor.obj vector.obj util.obj | |||
# We ignore warning C4127: we sometimes use a conditional that depending | |||
# on the parameters results in a case where if (const) is the case. | |||
# The compiler should just optimise this away, but on MSVC we get | |||
# a compiler complaint. | |||
CFLAGS=/nologo /O2 /I ..\..\..\common /W4 /WX /wd4127 | |||
all: $(LIBRARY) | |||
# Make sure objects are recompiled if headers change. | |||
$(OBJECTS): *.h | |||
$(LIBRARY): $(OBJECTS) | |||
LIB.EXE /NOLOGO /WX /OUT:$@ $** | |||
clean: | |||
-DEL $(OBJECTS) | |||
-DEL $(LIBRARY) |
@@ -1,25 +0,0 @@ | |||
#ifndef PQCLEAN_HQC2561CCA2_LEAKTIME_API_H | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_API_H | |||
/** | |||
* \file api.h | |||
* \brief NIST KEM API used by the HQC_KEM IND-CCA2 scheme | |||
*/ | |||
#include <stdint.h> | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_CRYPTO_ALGNAME "HQC_256_1_CCA2" | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_CRYPTO_SECRETKEYBYTES 8029 | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_CRYPTO_PUBLICKEYBYTES 7989 | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_CRYPTO_BYTES 64 | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_CRYPTO_CIPHERTEXTBYTES 15961 | |||
// As a technicality, the public key is appended to the secret key in order to respect the NIST API. | |||
// Without this constraint, CRYPTO_SECRETKEYBYTES would be defined as 32 | |||
int PQCLEAN_HQC2561CCA2_LEAKTIME_crypto_kem_keypair(uint8_t *pk, uint8_t *sk); | |||
int PQCLEAN_HQC2561CCA2_LEAKTIME_crypto_kem_enc(uint8_t *ct, uint8_t *ss, const uint8_t *pk); | |||
int PQCLEAN_HQC2561CCA2_LEAKTIME_crypto_kem_dec(uint8_t *ss, const uint8_t *ct, const uint8_t *sk); | |||
#endif |
@@ -1,295 +0,0 @@ | |||
/** | |||
* @file bch.c | |||
* Constant time implementation of BCH codes | |||
*/ | |||
#include "bch.h" | |||
#include "fft.h" | |||
#include "gf.h" | |||
#include "parameters.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
static void unpack_message(uint8_t *message_unpacked, const uint8_t *message); | |||
static void lfsr_encode(uint8_t *codeword, const uint8_t *message); | |||
static void pack_codeword(uint8_t *codeword, const uint8_t *codeword_unpacked); | |||
static size_t compute_elp(uint16_t *sigma, const uint16_t *syndromes); | |||
static void message_from_codeword(uint8_t *message, const uint8_t *codeword); | |||
static void compute_syndromes(uint16_t *syndromes, const uint8_t *vector); | |||
static void compute_roots(uint8_t *error, const uint16_t *sigma); | |||
/** | |||
* @brief Unpacks the message message to the array message_unpacked where each byte stores a bit of the message | |||
* | |||
* @param[out] message_unpacked Array of VEC_K_SIZE_BYTES bytes receiving the unpacked message | |||
* @param[in] message Array of PARAM_K bytes storing the packed message | |||
*/ | |||
static void unpack_message(uint8_t *message_unpacked, const uint8_t *message) { | |||
for (size_t i = 0; i < (VEC_K_SIZE_BYTES - (PARAM_K % 8 != 0)); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
message_unpacked[j + 8 * i] = (message[i] >> j) & 0x01; | |||
} | |||
} | |||
for (int8_t j = 0; j < PARAM_K % 8; ++j) { | |||
message_unpacked[j + 8 * (VEC_K_SIZE_BYTES - 1)] = (message[VEC_K_SIZE_BYTES - 1] >> j) & 0x01; | |||
} | |||
} | |||
/** | |||
* @brief Encodes the message message to a codeword codeword using the generator polynomial bch_poly of the code | |||
* | |||
* @param[out] codeword Array of PARAM_N1 bytes receiving the codeword | |||
* @param[in] message Array of PARAM_K bytes storing the message to encode | |||
*/ | |||
static void lfsr_encode(uint8_t *codeword, const uint8_t *message) { | |||
uint8_t gate_value = 0; | |||
uint8_t bch_poly[PARAM_G] = PARAM_BCH_POLY; | |||
// Compute the Parity-check digits | |||
for (int16_t i = PARAM_K - 1; i >= 0; --i) { | |||
gate_value = message[i] ^ codeword[PARAM_N1 - PARAM_K - 1]; | |||
for (size_t j = PARAM_N1 - PARAM_K - 1; j; --j) { | |||
codeword[j] = codeword[j - 1] ^ (-gate_value & bch_poly[j]); | |||
} | |||
codeword[0] = gate_value; | |||
} | |||
// Add the message | |||
memcpy(codeword + PARAM_N1 - PARAM_K, message, PARAM_K); | |||
} | |||
/** | |||
* @brief Packs the codeword from an array codeword_unpacked where each byte stores a bit to a compact array codeword | |||
* | |||
* @param[out] codeword Array of VEC_N1_SIZE_BYTES bytes receiving the packed codeword | |||
* @param[in] codeword_unpacked Array of PARAM_N1 bytes storing the unpacked codeword | |||
*/ | |||
static void pack_codeword(uint8_t *codeword, const uint8_t *codeword_unpacked) { | |||
for (size_t i = 0; i < (VEC_N1_SIZE_BYTES - (PARAM_N1 % 8 != 0)); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
codeword[i] |= codeword_unpacked[j + 8 * i] << j; | |||
} | |||
} | |||
for (size_t j = 0; j < PARAM_N1 % 8; ++j) { | |||
codeword[VEC_N1_SIZE_BYTES - 1] |= codeword_unpacked[j + 8 * (VEC_N1_SIZE_BYTES - 1)] << j; | |||
} | |||
} | |||
/** | |||
* @brief Encodes a message message of PARAM_K bits to a BCH codeword codeword of PARAM_N1 bits | |||
* | |||
* Following @cite lin1983error (Chapter 4 - Cyclic Codes), | |||
* We perform a systematic encoding using a linear (PARAM_N1 - PARAM_K)-stage shift register | |||
* with feedback connections based on the generator polynomial bch_poly of the BCH code. | |||
* | |||
* @param[out] codeword Array of size VEC_N1_SIZE_BYTES receiving the encoded message | |||
* @param[in] message Array of size VEC_K_SIZE_BYTES storing the message | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_bch_code_encode(uint8_t *codeword, const uint8_t *message) { | |||
uint8_t message_unpacked[PARAM_K]; | |||
uint8_t codeword_unpacked[PARAM_N1] = {0}; | |||
unpack_message(message_unpacked, message); | |||
lfsr_encode(codeword_unpacked, message_unpacked); | |||
pack_codeword(codeword, codeword_unpacked); | |||
} | |||
/** | |||
* @brief Computes the error locator polynomial (ELP) sigma | |||
* | |||
* This is a constant time implementation of Berlekamp's simplified algorithm (see @cite joiner1995decoding). <br> | |||
* We use the letter p for rho which is initialized at -1/2. <br> | |||
* The array X_sigma_p represents the polynomial X^(2(mu-rho))*sigma_p(X). <br> | |||
* Instead of maintaining a list of sigmas, we update in place both sigma and X_sigma_p. <br> | |||
* sigma_copy serves as a temporary save of sigma in case X_sigma_p needs to be updated. <br> | |||
* We can properly correct only if the degree of sigma does not exceed PARAM_DELTA. | |||
* This means only the first PARAM_DELTA + 1 coefficients of sigma are of value | |||
* and we only need to save its first PARAM_DELTA - 1 coefficients. | |||
* | |||
* @returns the degree of the ELP sigma | |||
* @param[out] sigma Array of size (at least) PARAM_DELTA receiving the ELP | |||
* @param[in] syndromes Array of size (at least) 2*PARAM_DELTA storing the syndromes | |||
*/ | |||
static size_t compute_elp(uint16_t *sigma, const uint16_t *syndromes) { | |||
sigma[0] = 1; | |||
size_t deg_sigma = 0; | |||
size_t deg_sigma_p = 0; | |||
uint16_t sigma_copy[PARAM_DELTA - 1] = {0}; | |||
size_t deg_sigma_copy = 0; | |||
uint16_t X_sigma_p[PARAM_DELTA + 1] = {0, 1}; | |||
int32_t pp = -1; // 2*rho | |||
uint16_t d_p = 1; | |||
uint16_t d = syndromes[0]; | |||
for (size_t mu = 0; mu < PARAM_DELTA; ++mu) { | |||
// Save sigma in case we need it to update X_sigma_p | |||
memcpy(sigma_copy, sigma, 2 * (PARAM_DELTA - 1)); | |||
deg_sigma_copy = deg_sigma; | |||
uint16_t dd = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(d, PQCLEAN_HQC2561CCA2_LEAKTIME_gf_inverse(d_p)); // 0 if(d == 0) | |||
for (size_t i = 1; (i <= 2 * mu + 1) && (i <= PARAM_DELTA); ++i) { | |||
sigma[i] ^= PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(dd, X_sigma_p[i]); | |||
} | |||
size_t deg_X = 2 * mu - pp; // 2*(mu-rho) | |||
size_t deg_X_sigma_p = deg_X + deg_sigma_p; | |||
// mask1 = 0xffff if(d != 0) and 0 otherwise | |||
int16_t mask1 = -((uint16_t) - d >> 15); | |||
// mask2 = 0xffff if(deg_X_sigma_p > deg_sigma) and 0 otherwise | |||
int16_t mask2 = -((uint16_t) (deg_sigma - deg_X_sigma_p) >> 15); | |||
// mask12 = 0xffff if the deg_sigma increased and 0 otherwise | |||
int16_t mask12 = mask1 & mask2; | |||
deg_sigma = (mask12 & deg_X_sigma_p) ^ (~mask12 & deg_sigma); | |||
if (mu == PARAM_DELTA - 1) { | |||
break; | |||
} | |||
// Update pp, d_p and X_sigma_p if needed | |||
pp = (mask12 & (2 * mu)) ^ (~mask12 & pp); | |||
d_p = (mask12 & d) ^ (~mask12 & d_p); | |||
for (size_t i = PARAM_DELTA - 1; i; --i) { | |||
X_sigma_p[i + 1] = (mask12 & sigma_copy[i - 1]) ^ (~mask12 & X_sigma_p[i - 1]); | |||
} | |||
X_sigma_p[1] = 0; | |||
X_sigma_p[0] = 0; | |||
deg_sigma_p = (mask12 & deg_sigma_copy) ^ (~mask12 & deg_sigma_p); | |||
// Compute the next discrepancy | |||
d = syndromes[2 * mu + 2]; | |||
for (size_t i = 1; (i <= 2 * mu + 1) && (i <= PARAM_DELTA); ++i) { | |||
d ^= PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(sigma[i], syndromes[2 * mu + 2 - i]); | |||
} | |||
} | |||
return deg_sigma; | |||
} | |||
/** | |||
* @brief Retrieves the message message from the codeword codeword | |||
* | |||
* Since we performed a systematic encoding, the message is the last PARAM_K bits of the codeword. | |||
* | |||
* @param[out] message Array of size VEC_K_SIZE_BYTES receiving the message | |||
* @param[in] codeword Array of size VEC_N1_SIZE_BYTES storing the codeword | |||
*/ | |||
static void message_from_codeword(uint8_t *message, const uint8_t *codeword) { | |||
int32_t val = PARAM_N1 - PARAM_K; | |||
uint8_t mask1 = 0xff << val % 8; | |||
uint8_t mask2 = 0xff >> (8 - val % 8); | |||
size_t index = val / 8; | |||
for (size_t i = 0; i < VEC_K_SIZE_BYTES - 1; ++i) { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
uint8_t message2 = (codeword[++index] & mask2) << (8 - val % 8); | |||
message[i] = message1 | message2; | |||
} | |||
// Last byte (8-val % 8 is the number of bits given by message1) | |||
if ((PARAM_K % 8 == 0) || (8 - val % 8 < PARAM_K % 8)) { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
uint8_t message2 = (codeword[++index] & mask2) << (8 - val % 8); | |||
message[VEC_K_SIZE_BYTES - 1] = message1 | message2; | |||
} else { | |||
uint8_t message1 = (codeword[index] & mask1) >> val % 8; | |||
message[VEC_K_SIZE_BYTES - 1] = message1; | |||
} | |||
} | |||
/** | |||
* @brief Computes the 2^PARAM_DELTA syndromes from the received vector vector | |||
* | |||
* Syndromes are the sum of powers of alpha weighted by vector's coefficients. | |||
* To do so, we use the additive FFT transpose, which takes as input a family w of GF(2^PARAM_M) elements | |||
* and outputs the weighted power sums of these w. <br> | |||
* Therefore, this requires twisting and applying a permutation before feeding vector to the fft transpose. <br> | |||
* For more details see Berstein, Chou and Schawbe's explanations: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] syndromes Array of size 2^(PARAM_FFT_T) receiving the 2*PARAM_DELTA syndromes | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES storing the received word | |||
*/ | |||
static void compute_syndromes(uint16_t *syndromes, const uint8_t *vector) { | |||
uint16_t w[1 << PARAM_M]; | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(w, vector); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_fft_t(syndromes, w, 2 * PARAM_DELTA); | |||
} | |||
/** | |||
* @brief Computes the error polynomial error from the error locator polynomial sigma | |||
* | |||
* See function fft for more details. | |||
* | |||
* @param[out] err Array of VEC_N1_SIZE_BYTES elements receiving the error polynomial | |||
* @param[in] sigma Array of 2^PARAM_FFT elements storing the error locator polynomial | |||
*/ | |||
static void compute_roots(uint8_t *error, const uint16_t *sigma) { | |||
uint16_t w[1 << PARAM_M] = {0}; // w will receive the evaluation of sigma in all field elements | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_fft(w, sigma, PARAM_DELTA + 1); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_fft_retrieve_bch_error_poly(error, w); | |||
} | |||
/** | |||
* @brief Decodes the received word | |||
* | |||
* This function relies on four steps: | |||
* <ol> | |||
* <li> The first step, done by additive FFT transpose, is the computation of the 2*PARAM_DELTA syndromes. | |||
* <li> The second step is the computation of the error-locator polynomial sigma. | |||
* <li> The third step, done by additive FFT, is finding the error-locator numbers by calculating the roots of the polynomial sigma and takings their inverses. | |||
* <li> The fourth step is the correction of the errors in the received polynomial. | |||
* </ol> | |||
* For a more complete picture on BCH decoding, see Shu. Lin and Daniel J. Costello in Error Control Coding: Fundamentals and Applications @cite lin1983error | |||
* | |||
* @param[out] message Array of size VEC_K_SIZE_BYTES receiving the decoded message | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES storing the received word | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_bch_code_decode(uint8_t *message, uint8_t *vector) { | |||
uint16_t syndromes[1 << PARAM_FFT_T]; | |||
uint16_t sigma[1 << PARAM_FFT] = {0}; | |||
uint8_t error[(1 << PARAM_M) / 8] = {0}; | |||
// Calculate the 2*PARAM_DELTA syndromes | |||
compute_syndromes(syndromes, vector); | |||
// Compute the error locator polynomial sigma | |||
// Sigma's degree is at most PARAM_DELTA but the FFT requires the extra room | |||
compute_elp(sigma, syndromes); | |||
// Compute the error polynomial error | |||
compute_roots(error, sigma); | |||
// Add the error polynomial to the received polynomial | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_add(vector, vector, error, VEC_N1_SIZE_BYTES); | |||
// Retrieve the message from the decoded codeword | |||
message_from_codeword(message, vector); | |||
} |
@@ -1,16 +0,0 @@ | |||
#ifndef PQCLEAN_HQC2561CCA2_LEAKTIME_BCH_H | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_BCH_H | |||
/** | |||
* @file bch.h | |||
* Header file of bch.c | |||
*/ | |||
#include "parameters.h" | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_bch_code_encode(uint8_t *codeword, const uint8_t *message); | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_bch_code_decode(uint8_t *message, uint8_t *vector); | |||
#endif |
@@ -1,628 +0,0 @@ | |||
/** | |||
* @file fft.c | |||
* Implementation of the additive FFT and its transpose. | |||
* This implementation is based on the paper from Gao and Mateer: <br> | |||
* Shuhong Gao and Todd Mateer, Additive Fast Fourier Transforms over Finite Fields, | |||
* IEEE Transactions on Information Theory 56 (2010), 6265--6272. | |||
* http://www.math.clemson.edu/~sgao/papers/GM10.pdf <br> | |||
* and includes improvements proposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
*/ | |||
#include "fft.h" | |||
#include "gf.h" | |||
#include "parameters.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
static void compute_fft_betas(uint16_t *betas); | |||
static void compute_subset_sums(uint16_t *subset_sums, const uint16_t *set, size_t set_size); | |||
static void radix_t(uint16_t *f, const uint16_t *f0, const uint16_t *f1, uint32_t m_f); | |||
static void fft_t_rec(uint16_t *f, const uint16_t *w, size_t f_coeffs, uint8_t m, uint32_t m_f, const uint16_t *betas); | |||
static void radix(uint16_t *f0, uint16_t *f1, const uint16_t *f, uint32_t m_f); | |||
static void fft_rec(uint16_t *w, uint16_t *f, size_t f_coeffs, uint8_t m, uint32_t m_f, const uint16_t *betas); | |||
/** | |||
* @brief Computes the basis of betas (omitting 1) used in the additive FFT and its transpose | |||
* | |||
* @param[out] betas Array of size PARAM_M-1 | |||
*/ | |||
static void compute_fft_betas(uint16_t *betas) { | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
betas[i] = 1 << (PARAM_M - 1 - i); | |||
} | |||
} | |||
/** | |||
* @brief Computes the subset sums of the given set | |||
* | |||
* The array subset_sums is such that its ith element is | |||
* the subset sum of the set elements given by the binary form of i. | |||
* | |||
* @param[out] subset_sums Array of size 2^set_size receiving the subset sums | |||
* @param[in] set Array of set_size elements | |||
* @param[in] set_size Size of the array set | |||
*/ | |||
static void compute_subset_sums(uint16_t *subset_sums, const uint16_t *set, size_t set_size) { | |||
subset_sums[0] = 0; | |||
for (size_t i = 0; i < set_size; ++i) { | |||
for (size_t j = 0; j < (((size_t)1) << i); ++j) { | |||
subset_sums[(((size_t)1) << i) + j] = set[i] ^ subset_sums[j]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Transpose of the linear radix conversion | |||
* | |||
* This is a direct transposition of the radix function | |||
* implemented following the process of transposing a linear function as exposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f Array of size a power of 2 | |||
* @param[in] f0 Array half the size of f | |||
* @param[in] f1 Array half the size of f | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the number of coefficients of f | |||
*/ | |||
static void radix_t(uint16_t *f, const uint16_t *f0, const uint16_t *f1, uint32_t m_f) { | |||
switch (m_f) { | |||
case 4: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
f[4] = f[2] ^ f0[2]; | |||
f[5] = f[3] ^ f1[2]; | |||
f[6] = f[4] ^ f0[3] ^ f1[2]; | |||
f[7] = f[3] ^ f0[3] ^ f1[3]; | |||
f[8] = f[4] ^ f0[4]; | |||
f[9] = f[5] ^ f1[4]; | |||
f[10] = f[6] ^ f0[5] ^ f1[4]; | |||
f[11] = f[7] ^ f0[5] ^ f1[4] ^ f1[5]; | |||
f[12] = f[8] ^ f0[5] ^ f0[6] ^ f1[4]; | |||
f[13] = f[7] ^ f[9] ^ f[11] ^ f1[6]; | |||
f[14] = f[6] ^ f0[6] ^ f0[7] ^ f1[6]; | |||
f[15] = f[7] ^ f0[7] ^ f1[7]; | |||
return; | |||
case 3: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
f[4] = f[2] ^ f0[2]; | |||
f[5] = f[3] ^ f1[2]; | |||
f[6] = f[4] ^ f0[3] ^ f1[2]; | |||
f[7] = f[3] ^ f0[3] ^ f1[3]; | |||
return; | |||
case 2: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
f[2] = f0[1] ^ f1[0]; | |||
f[3] = f[2] ^ f1[1]; | |||
return; | |||
case 1: | |||
f[0] = f0[0]; | |||
f[1] = f1[0]; | |||
return; | |||
default: | |||
; | |||
size_t n = ((size_t)1) << (m_f - 2); | |||
uint16_t Q0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t Q1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t Q[1 << 2 * (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t R[1 << 2 * (PARAM_FFT_T - 2)] = {0}; | |||
memcpy(Q0, f0 + n, 2 * n); | |||
memcpy(Q1, f1 + n, 2 * n); | |||
memcpy(R0, f0, 2 * n); | |||
memcpy(R1, f1, 2 * n); | |||
radix_t (Q, Q0, Q1, m_f - 1); | |||
radix_t (R, R0, R1, m_f - 1); | |||
memcpy(f, R, 4 * n); | |||
memcpy(f + 2 * n, R + n, 2 * n); | |||
memcpy(f + 3 * n, Q + n, 2 * n); | |||
for (size_t i = 0; i < n; ++i) { | |||
f[2 * n + i] ^= Q[i]; | |||
f[3 * n + i] ^= f[2 * n + i]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Recursively computes syndromes of family w | |||
* | |||
* This function is a subroutine of the function fft_t | |||
* | |||
* @param[out] f Array receiving the syndromes | |||
* @param[in] w Array storing the family | |||
* @param[in] f_coeffs Length of syndromes vector | |||
* @param[in] m 2^m is the smallest power of 2 greater or equal to the length of family w | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the length of f | |||
* @param[in] betas FFT constants | |||
*/ | |||
static void fft_t_rec(uint16_t *f, const uint16_t *w, size_t f_coeffs, | |||
uint8_t m, uint32_t m_f, const uint16_t *betas) { | |||
size_t k = ((size_t)1) << (m - 1); | |||
uint16_t gammas[PARAM_M - 2] = {0}; | |||
uint16_t deltas[PARAM_M - 2] = {0}; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
uint16_t u[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t f0[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT_T - 2)] = {0}; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)] = {0}; | |||
// Step 1 | |||
if (m_f == 1) { | |||
for (size_t i = 0; i < (((size_t)1) << m); ++i) { | |||
f[0] ^= w[i]; | |||
} | |||
for (size_t j = 0; j < m; ++j) { | |||
for (size_t ki = 0; ki < (((size_t)1) << j); ++ki) { | |||
size_t index = (((size_t)1) << j) + ki; | |||
betas_sums[index] = betas_sums[ki] ^ betas[j]; | |||
f[1] ^= PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(betas_sums[index], w[index]); | |||
} | |||
} | |||
return; | |||
} | |||
// Compute gammas and deltas | |||
for (uint8_t i = 0; i < m - 1; ++i) { | |||
gammas[i] = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(betas[i], PQCLEAN_HQC2561CCA2_LEAKTIME_gf_inverse(betas[m - 1])); | |||
deltas[i] = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_square(gammas[i]) ^ gammas[i]; | |||
} | |||
// Compute gammas subset sums | |||
compute_subset_sums(gammas_sums, gammas, m - 1); | |||
/* Step 6: Compute u and v from w (aka w) | |||
* w[i] = u[i] + G[i].v[i] | |||
* w[k+i] = w[i] + v[i] = u[i] + (G[i]+1).v[i] | |||
* Transpose: | |||
* u[i] = w[i] + w[k+i] | |||
* v[i] = G[i].w[i] + (G[i]+1).w[k+i] = G[i].u[i] + w[k+i] */ | |||
if (f_coeffs <= 3) { // 3-coefficient polynomial f case | |||
// Step 5: Compute f0 from u and f1 from v | |||
f1[1] = 0; | |||
u[0] = w[0] ^ w[k]; | |||
f1[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
f1[0] ^= PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(gammas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
} else { | |||
uint16_t v[1 << (PARAM_M - 2)] = {0}; | |||
u[0] = w[0] ^ w[k]; | |||
v[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
v[i] = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(gammas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
// Step 5: Compute f0 from u and f1 from v | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
fft_t_rec(f1, v, f_coeffs / 2, m - 1, m_f - 1, deltas); | |||
} | |||
// Step 3: Compute g from g0 and g1 | |||
radix_t(f, f0, f1, m_f); | |||
// Step 2: compute f from g | |||
if (betas[m - 1] != 1) { | |||
uint16_t beta_m_pow = 1; | |||
for (size_t i = 1; i < (((size_t)1) << m_f); ++i) { | |||
beta_m_pow = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(beta_m_pow, betas[m - 1]); | |||
f[i] = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(beta_m_pow, f[i]); | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Computes the syndromes f of the family w | |||
* | |||
* Since the syndromes linear map is the transpose of multipoint evaluation, | |||
* it uses exactly the same constants, either hardcoded or precomputed by compute_fft_lut(...). <br> | |||
* This follows directives from Bernstein, Chou and Schwabe given here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f Array of size 2*(PARAM_FFT_T) elements receiving the syndromes | |||
* @param[in] w Array of PARAM_GF_MUL_ORDER+1 elements | |||
* @param[in] f_coeffs Length of syndromes vector f | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_fft_t(uint16_t *f, const uint16_t *w, size_t f_coeffs) { | |||
// Transposed from Gao and Mateer algorithm | |||
uint16_t betas[PARAM_M - 1]; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
uint16_t u[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t deltas[PARAM_M - 1]; | |||
uint16_t f0[1 << (PARAM_FFT_T - 1)]; | |||
uint16_t f1[1 << (PARAM_FFT_T - 1)]; | |||
compute_fft_betas(betas); | |||
compute_subset_sums(betas_sums, betas, PARAM_M - 1); | |||
/* Step 6: Compute u and v from w (aka w) | |||
* | |||
* We had: | |||
* w[i] = u[i] + G[i].v[i] | |||
* w[k+i] = w[i] + v[i] = u[i] + (G[i]+1).v[i] | |||
* Transpose: | |||
* u[i] = w[i] + w[k+i] | |||
* v[i] = G[i].w[i] + (G[i]+1).w[k+i] = G[i].u[i] + w[k+i] */ | |||
u[0] = w[0] ^ w[k]; | |||
v[0] = w[k]; | |||
for (size_t i = 1; i < k; ++i) { | |||
u[i] = w[i] ^ w[k + i]; | |||
v[i] = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(betas_sums[i], u[i]) ^ w[k + i]; | |||
} | |||
// Compute deltas | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
deltas[i] = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_square(betas[i]) ^ betas[i]; | |||
} | |||
// Step 5: Compute f0 from u and f1 from v | |||
fft_t_rec(f0, u, (f_coeffs + 1) / 2, PARAM_M - 1, PARAM_FFT_T - 1, deltas); | |||
fft_t_rec(f1, v, f_coeffs / 2, PARAM_M - 1, PARAM_FFT_T - 1, deltas); | |||
// Step 3: Compute g from g0 and g1 | |||
radix_t(f, f0, f1, PARAM_FFT_T); | |||
// Step 2: beta_m = 1 so f = g | |||
} | |||
/** | |||
* @brief Computes the radix conversion of a polynomial f in GF(2^m)[x] | |||
* | |||
* Computes f0 and f1 such that f(x) = f0(x^2-x) + x.f1(x^2-x) | |||
* as proposed by Bernstein, Chou and Schwabe: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf | |||
* | |||
* @param[out] f0 Array half the size of f | |||
* @param[out] f1 Array half the size of f | |||
* @param[in] f Array of size a power of 2 | |||
* @param[in] m_f 2^{m_f} is the smallest power of 2 greater or equal to the number of coefficients of f | |||
*/ | |||
static void radix(uint16_t *f0, uint16_t *f1, const uint16_t *f, uint32_t m_f) { | |||
switch (m_f) { | |||
case 4: | |||
f0[4] = f[8] ^ f[12]; | |||
f0[6] = f[12] ^ f[14]; | |||
f0[7] = f[14] ^ f[15]; | |||
f1[5] = f[11] ^ f[13]; | |||
f1[6] = f[13] ^ f[14]; | |||
f1[7] = f[15]; | |||
f0[5] = f[10] ^ f[12] ^ f1[5]; | |||
f1[4] = f[9] ^ f[13] ^ f0[5]; | |||
f0[0] = f[0]; | |||
f1[3] = f[7] ^ f[11] ^ f[15]; | |||
f0[3] = f[6] ^ f[10] ^ f[14] ^ f1[3]; | |||
f0[2] = f[4] ^ f0[4] ^ f0[3] ^ f1[3]; | |||
f1[1] = f[3] ^ f[5] ^ f[9] ^ f[13] ^ f1[3]; | |||
f1[2] = f[3] ^ f1[1] ^ f0[3]; | |||
f0[1] = f[2] ^ f0[2] ^ f1[1]; | |||
f1[0] = f[1] ^ f0[1]; | |||
return; | |||
case 3: | |||
f0[0] = f[0]; | |||
f0[2] = f[4] ^ f[6]; | |||
f0[3] = f[6] ^ f[7]; | |||
f1[1] = f[3] ^ f[5] ^ f[7]; | |||
f1[2] = f[5] ^ f[6]; | |||
f1[3] = f[7]; | |||
f0[1] = f[2] ^ f0[2] ^ f1[1]; | |||
f1[0] = f[1] ^ f0[1]; | |||
return; | |||
case 2: | |||
f0[0] = f[0]; | |||
f0[1] = f[2] ^ f[3]; | |||
f1[0] = f[1] ^ f0[1]; | |||
f1[1] = f[3]; | |||
return; | |||
case 1: | |||
f0[0] = f[0]; | |||
f1[0] = f[1]; | |||
return; | |||
default: | |||
; | |||
size_t n = ((size_t)1) << (m_f - 2); | |||
uint16_t Q[2 * (1 << (PARAM_FFT - 2))]; | |||
uint16_t R[2 * (1 << (PARAM_FFT - 2))]; | |||
uint16_t Q0[1 << (PARAM_FFT - 2)]; | |||
uint16_t Q1[1 << (PARAM_FFT - 2)]; | |||
uint16_t R0[1 << (PARAM_FFT - 2)]; | |||
uint16_t R1[1 << (PARAM_FFT - 2)]; | |||
memcpy(Q, f + 3 * n, 2 * n); | |||
memcpy(Q + n, f + 3 * n, 2 * n); | |||
memcpy(R, f, 4 * n); | |||
for (size_t i = 0; i < n; ++i) { | |||
Q[i] ^= f[2 * n + i]; | |||
R[n + i] ^= Q[i]; | |||
} | |||
radix(Q0, Q1, Q, m_f - 1); | |||
radix(R0, R1, R, m_f - 1); | |||
memcpy(f0, R0, 2 * n); | |||
memcpy(f0 + n, Q0, 2 * n); | |||
memcpy(f1, R1, 2 * n); | |||
memcpy(f1 + n, Q1, 2 * n); | |||
} | |||
} | |||
/** | |||
* @brief Evaluates f at all subset sums of a given set | |||
* | |||
* This function is a subroutine of the function fft. | |||
* | |||
* @param[out] w Array | |||
* @param[in] f Array | |||
* @param[in] f_coeffs Number of coefficients of f | |||
* @param[in] m Number of betas | |||
* @param[in] m_f Number of coefficients of f (one more than its degree) | |||
* @param[in] betas FFT constants | |||
*/ | |||
static void fft_rec(uint16_t *w, uint16_t *f, size_t f_coeffs, | |||
uint8_t m, uint32_t m_f, const uint16_t *betas) { | |||
uint16_t f0[1 << (PARAM_FFT - 2)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT - 2)] = {0}; | |||
uint16_t gammas[PARAM_M - 2] = {0}; | |||
uint16_t deltas[PARAM_M - 2] = {0}; | |||
size_t k = ((size_t)1) << (m - 1); | |||
uint16_t gammas_sums[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t u[1 << (PARAM_M - 2)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 2)] = {0}; | |||
// Step 1 | |||
if (m_f == 1) { | |||
uint16_t tmp[PARAM_M - (PARAM_FFT - 1)]; | |||
for (size_t i = 0; i < m; ++i) { | |||
tmp[i] = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(betas[i], f[1]); | |||
} | |||
w[0] = f[0]; | |||
for (size_t j = 0; j < m; ++j) { | |||
for (size_t ki = 0; ki < (((size_t)1) << j); ++ki) { | |||
w[(((size_t)1) << j) + ki] = w[ki] ^ tmp[j]; | |||
} | |||
} | |||
return; | |||
} | |||
// Step 2: compute g | |||
if (betas[m - 1] != 1) { | |||
uint16_t beta_m_pow = 1; | |||
for (size_t i = 1; i < (((size_t)1) << m_f); ++i) { | |||
beta_m_pow = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(beta_m_pow, betas[m - 1]); | |||
f[i] = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(beta_m_pow, f[i]); | |||
} | |||
} | |||
// Step 3 | |||
radix(f0, f1, f, m_f); | |||
// Step 4: compute gammas and deltas | |||
for (uint8_t i = 0; i < m - 1; ++i) { | |||
gammas[i] = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(betas[i], PQCLEAN_HQC2561CCA2_LEAKTIME_gf_inverse(betas[m - 1])); | |||
deltas[i] = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_square(gammas[i]) ^ gammas[i]; | |||
} | |||
// Compute gammas sums | |||
compute_subset_sums(gammas_sums, gammas, m - 1); | |||
// Step 5 | |||
fft_rec(u, f0, (f_coeffs + 1) / 2, m - 1, m_f - 1, deltas); | |||
if (f_coeffs <= 3) { // 3-coefficient polynomial f case: f1 is constant | |||
w[0] = u[0]; | |||
w[k] = u[0] ^ f1[0]; | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(gammas_sums[i], f1[0]); | |||
w[k + i] = w[i] ^ f1[0]; | |||
} | |||
} else { | |||
fft_rec(v, f1, f_coeffs / 2, m - 1, m_f - 1, deltas); | |||
// Step 6 | |||
memcpy(w + k, v, 2 * k); | |||
w[0] = u[0]; | |||
w[k] ^= u[0]; | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(gammas_sums[i], v[i]); | |||
w[k + i] ^= w[i]; | |||
} | |||
} | |||
} | |||
/** | |||
* @brief Evaluates f on all fields elements using an additive FFT algorithm | |||
* | |||
* f_coeffs is the number of coefficients of f (one less than its degree). <br> | |||
* The FFT proceeds recursively to evaluate f at all subset sums of a basis B. <br> | |||
* This implementation is based on the paper from Gao and Mateer: <br> | |||
* Shuhong Gao and Todd Mateer, Additive Fast Fourier Transforms over Finite Fields, | |||
* IEEE Transactions on Information Theory 56 (2010), 6265--6272. | |||
* http://www.math.clemson.edu/~sgao/papers/GM10.pdf <br> | |||
* and includes improvements proposed by Bernstein, Chou and Schwabe here: | |||
* https://binary.cr.yp.to/mcbits-20130616.pdf <br> | |||
* Constants betas, gammas and deltas involved in the algorithm are either hardcoded or precomputed | |||
* by the subroutine compute_fft_lut(...). <br> | |||
* Note that on this first call (as opposed to the recursive calls to fft_rec), gammas are equal to betas, | |||
* meaning the first gammas subset sums are actually the subset sums of betas (except 1). <br> | |||
* Also note that f is altered during computation (twisted at each level). | |||
* | |||
* @param[out] w Array | |||
* @param[in] f Array of 2^PARAM_FFT elements | |||
* @param[in] f_coeffs Number coefficients of f (i.e. deg(f)+1) | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_fft(uint16_t *w, const uint16_t *f, size_t f_coeffs) { | |||
uint16_t betas[PARAM_M - 1] = {0}; | |||
uint16_t betas_sums[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t f0[1 << (PARAM_FFT - 1)] = {0}; | |||
uint16_t f1[1 << (PARAM_FFT - 1)] = {0}; | |||
uint16_t deltas[PARAM_M - 1]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
uint16_t u[1 << (PARAM_M - 1)] = {0}; | |||
uint16_t v[1 << (PARAM_M - 1)] = {0}; | |||
// Follows Gao and Mateer algorithm | |||
compute_fft_betas(betas); | |||
// Step 1: PARAM_FFT > 1, nothing to do | |||
// Compute gammas sums | |||
compute_subset_sums(betas_sums, betas, PARAM_M - 1); | |||
// Step 2: beta_m = 1, nothing to do | |||
// Step 3 | |||
radix(f0, f1, f, PARAM_FFT); | |||
// Step 4: Compute deltas | |||
for (size_t i = 0; i < PARAM_M - 1; ++i) { | |||
deltas[i] = PQCLEAN_HQC2561CCA2_LEAKTIME_gf_square(betas[i]) ^ betas[i]; | |||
} | |||
// Step 5 | |||
fft_rec(u, f0, (f_coeffs + 1) / 2, PARAM_M - 1, PARAM_FFT - 1, deltas); | |||
fft_rec(v, f1, f_coeffs / 2, PARAM_M - 1, PARAM_FFT - 1, deltas); | |||
// Step 6, 7 and error polynomial computation | |||
memcpy(w + k, v, 2 * k); | |||
// Check if 0 is root | |||
w[0] = u[0]; | |||
// Check if 1 is root | |||
w[k] ^= u[0]; | |||
// Find other roots | |||
for (size_t i = 1; i < k; ++i) { | |||
w[i] = u[i] ^ PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(betas_sums[i], v[i]); | |||
w[k + i] ^= w[i]; | |||
} | |||
} | |||
/** | |||
* @brief Arranges the received word vector in a form w such that applying the additive FFT transpose to w yields the BCH syndromes of the received word vector. | |||
* | |||
* Since the received word vector gives coefficients of the primitive element alpha, we twist accordingly. <br> | |||
* Furthermore, the additive FFT transpose needs elements indexed by their decomposition on the chosen basis, | |||
* so we apply the adequate permutation. | |||
* | |||
* @param[out] w Array of size 2^PARAM_M | |||
* @param[in] vector Array of size VEC_N1_SIZE_BYTES | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(uint16_t *w, const uint8_t *vector) { | |||
uint16_t r[1 << PARAM_M]; | |||
uint16_t gammas[PARAM_M - 1]; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
// Unpack the received word vector into array r | |||
size_t i; | |||
for (i = 0; i < VEC_N1_SIZE_BYTES - (PARAM_N1 % 8 != 0); ++i) { | |||
for (size_t j = 0; j < 8; ++j) { | |||
r[8 * i + j] = (vector[i] >> j) & 1; | |||
} | |||
} | |||
// Last byte | |||
for (size_t j = 0; j < PARAM_N1 % 8; ++j) { | |||
r[8 * i + j] = (vector[i] >> j) & 1; | |||
} | |||
// Complete r with zeros | |||
memset(r + PARAM_N1, 0, 2 * ((1 << PARAM_M) - PARAM_N1)); | |||
compute_fft_betas(gammas); | |||
compute_subset_sums(gammas_sums, gammas, PARAM_M - 1); | |||
// Twist and permute r adequately to obtain w | |||
w[0] = 0; | |||
w[k] = -r[0] & 1; | |||
for (i = 1; i < k; ++i) { | |||
w[i] = -r[PQCLEAN_HQC2561CCA2_LEAKTIME_gf_log(gammas_sums[i])] & gammas_sums[i]; | |||
w[k + i] = -r[PQCLEAN_HQC2561CCA2_LEAKTIME_gf_log(gammas_sums[i] ^ 1)] & (gammas_sums[i] ^ 1); | |||
} | |||
} | |||
/** | |||
* @brief Retrieves the error polynomial error from the evaluations w of the ELP (Error Locator Polynomial) on all field elements. | |||
* | |||
* @param[out] error Array of size VEC_N1_SIZE_BYTES | |||
* @param[in] w Array of size 2^PARAM_M | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_fft_retrieve_bch_error_poly(uint8_t *error, const uint16_t *w) { | |||
uint16_t gammas[PARAM_M - 1]; | |||
uint16_t gammas_sums[1 << (PARAM_M - 1)]; | |||
size_t k = 1 << (PARAM_M - 1); | |||
size_t index = PARAM_GF_MUL_ORDER; | |||
compute_fft_betas(gammas); | |||
compute_subset_sums(gammas_sums, gammas, PARAM_M - 1); | |||
error[0] ^= 1 ^ ((uint16_t) - w[0] >> 15); | |||
uint8_t bit = 1 ^ ((uint16_t) - w[k] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
for (size_t i = 1; i < k; ++i) { | |||
index = PARAM_GF_MUL_ORDER - PQCLEAN_HQC2561CCA2_LEAKTIME_gf_log(gammas_sums[i]); | |||
bit = 1 ^ ((uint16_t) - w[i] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
index = PARAM_GF_MUL_ORDER - PQCLEAN_HQC2561CCA2_LEAKTIME_gf_log(gammas_sums[i] ^ 1); | |||
bit = 1 ^ ((uint16_t) - w[k + i] >> 15); | |||
error[index / 8] ^= bit << (index % 8); | |||
} | |||
} |
@@ -1,18 +0,0 @@ | |||
#ifndef PQCLEAN_HQC2561CCA2_LEAKTIME_FFT_H | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_FFT_H | |||
/** | |||
* @file fft.h | |||
* Header file of fft.c | |||
*/ | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_fft_t(uint16_t *f, const uint16_t *w, size_t f_coeffs); | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_fft_t_preprocess_bch_codeword(uint16_t *w, const uint8_t *vector); | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_fft(uint16_t *w, const uint16_t *f, size_t f_coeffs); | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_fft_retrieve_bch_error_poly(uint8_t *error, const uint16_t *w); | |||
#endif |
@@ -1,18 +0,0 @@ | |||
#ifndef PQCLEAN_HQC2561CCA2_LEAKTIME_GF_H | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_GF_H | |||
/** | |||
* @file gf.h | |||
* Header file of gf.c | |||
*/ | |||
#include <stddef.h> | |||
#include <stdint.h> | |||
uint16_t PQCLEAN_HQC2561CCA2_LEAKTIME_gf_log(uint16_t elt); | |||
uint16_t PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mul(uint16_t a, uint16_t b); | |||
uint16_t PQCLEAN_HQC2561CCA2_LEAKTIME_gf_square(uint16_t a); | |||
uint16_t PQCLEAN_HQC2561CCA2_LEAKTIME_gf_inverse(uint16_t a); | |||
uint16_t PQCLEAN_HQC2561CCA2_LEAKTIME_gf_mod(uint16_t i); | |||
#endif |
@@ -1,123 +0,0 @@ | |||
/** | |||
* \file gf2x.c | |||
* \brief Implementation of multiplication of two polynomials | |||
*/ | |||
#include "gf2x.h" | |||
#include "parameters.h" | |||
#include "util.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
#define WORD_TYPE uint64_t | |||
#define WORD_TYPE_BITS (sizeof(WORD_TYPE) * 8) | |||
#define UTILS_VECTOR_ARRAY_SIZE CEIL_DIVIDE(PARAM_N, WORD_TYPE_BITS) | |||
static int vect_mul_precompute_rows(WORD_TYPE *o, const WORD_TYPE *v); | |||
/** | |||
* @brief A subroutine used in the function sparse_dense_mul() | |||
* | |||
* @param[out] o Pointer to an array | |||
* @param[in] v Pointer to an array | |||
* @return 0 if precomputation is successful, -1 otherwise | |||
*/ | |||
static int vect_mul_precompute_rows(WORD_TYPE *o, const WORD_TYPE *v) { | |||
int8_t var; | |||
for (size_t i = 0; i < PARAM_N; ++i) { | |||
var = 0; | |||
// All the bits that we need are in the same block | |||
if (((i % WORD_TYPE_BITS) == 0) && (i != PARAM_N - (PARAM_N % WORD_TYPE_BITS))) { | |||
var = 1; | |||
} | |||
// Cases where the bits are in before the last block, the last block and the first block | |||
if (i > PARAM_N - WORD_TYPE_BITS) { | |||
if (i >= PARAM_N - (PARAM_N % WORD_TYPE_BITS)) { | |||
var = 2; | |||
} else { | |||
var = 3; | |||
} | |||
} | |||
switch (var) { | |||
case 0: | |||
// Take bits in the last block and the first one | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[(i / WORD_TYPE_BITS) + 1] << (WORD_TYPE_BITS - (i % WORD_TYPE_BITS)); | |||
break; | |||
case 1: | |||
o[i] = v[i / WORD_TYPE_BITS]; | |||
break; | |||
case 2: | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[0] << ((PARAM_N - i) % WORD_TYPE_BITS); | |||
break; | |||
case 3: | |||
o[i] = 0; | |||
o[i] += v[i / WORD_TYPE_BITS] >> (i % WORD_TYPE_BITS); | |||
o[i] += v[(i / WORD_TYPE_BITS) + 1] << (WORD_TYPE_BITS - (i % WORD_TYPE_BITS)); | |||
o[i] += v[0] << ((WORD_TYPE_BITS - i + (PARAM_N % WORD_TYPE_BITS)) % WORD_TYPE_BITS); | |||
break; | |||
default: | |||
return -1; | |||
} | |||
} | |||
return 0; | |||
} | |||
/** | |||
* @brief Multiplies two vectors | |||
* | |||
* This function multiplies two vectors: a sparse vector of Hamming weight equal to <b>weight</b> and a dense (random) vector. | |||
* The vector <b>a1</b> is the sparse vector and <b>a2</b> is the dense vector. | |||
* We notice that the idea is explained using vector of 32 bits elements instead of 64 (the algorithm works in booth cases). | |||
* | |||
* @param[out] o Pointer to a vector that is the result of the multiplication | |||
* @param[in] a1 Pointer to the sparse vector stored by position | |||
* @param[in] a2 Pointer to the dense vector | |||
* @param[in] weight Integer that is the weight of the sparse vector | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_vect_mul(uint8_t *o, const uint32_t *a1, const uint8_t *a2, uint16_t weight) { | |||
WORD_TYPE v1[UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
WORD_TYPE res[UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
WORD_TYPE precomputation_array [PARAM_N] = {0}; | |||
WORD_TYPE row [UTILS_VECTOR_ARRAY_SIZE] = {0}; | |||
uint32_t index; | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_load8_arr(v1, UTILS_VECTOR_ARRAY_SIZE, a2, VEC_N_SIZE_BYTES); | |||
vect_mul_precompute_rows(precomputation_array, v1); | |||
for (size_t i = 0; i < weight; ++i) { | |||
int32_t k = UTILS_VECTOR_ARRAY_SIZE; | |||
for (size_t j = 0; j < UTILS_VECTOR_ARRAY_SIZE - 1; ++j) { | |||
index = WORD_TYPE_BITS * (uint32_t)j - a1[i]; | |||
if (index > PARAM_N) { | |||
index += PARAM_N; | |||
} | |||
row[j] = precomputation_array[index]; | |||
} | |||
index = WORD_TYPE_BITS * (UTILS_VECTOR_ARRAY_SIZE - 1) - a1[i]; | |||
row[UTILS_VECTOR_ARRAY_SIZE - 1] = precomputation_array[(index < PARAM_N ? index : index + PARAM_N)] & BITMASK(PARAM_N, WORD_TYPE_BITS); | |||
while (k--) { | |||
res[k] ^= row[k]; | |||
} | |||
} | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_store8_arr(o, VEC_N_SIZE_BYTES, res, UTILS_VECTOR_ARRAY_SIZE); | |||
} |
@@ -1,13 +0,0 @@ | |||
#ifndef PQCLEAN_HQC2561CCA2_LEAKTIME_GF2X_H | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_GF2X_H | |||
/** | |||
* @file gf2x.h | |||
* @brief Header file for gf2x.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_vect_mul(uint8_t *o, const uint32_t *a1, const uint8_t *a2, uint16_t weight); | |||
#endif |
@@ -1,135 +0,0 @@ | |||
/** | |||
* @file hqc.c | |||
* @brief Implementation of hqc.h | |||
*/ | |||
#include "gf2x.h" | |||
#include "hqc.h" | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "randombytes.h" | |||
#include "tensor.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
/** | |||
* @brief Keygen of the HQC_PKE IND_CPA scheme | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the <b>seed</b> used to generate the vector <b>h</b>. | |||
* | |||
* The secret key is composed of the <b>seed</b> used to generate vectors <b>x</b> and <b>y</b>. | |||
* As a technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[out] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_pke_keygen(uint8_t *pk, uint8_t *sk) { | |||
AES_XOF_struct sk_seedexpander; | |||
AES_XOF_struct pk_seedexpander; | |||
uint8_t sk_seed[SEED_BYTES] = {0}; | |||
uint8_t pk_seed[SEED_BYTES] = {0}; | |||
uint8_t x[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t y[PARAM_OMEGA] = {0}; | |||
uint8_t h[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t s[VEC_N_SIZE_BYTES] = {0}; | |||
// Create seed_expanders for public key and secret key | |||
randombytes(sk_seed, SEED_BYTES); | |||
seedexpander_init(&sk_seedexpander, sk_seed, sk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
randombytes(pk_seed, SEED_BYTES); | |||
seedexpander_init(&pk_seedexpander, pk_seed, pk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
// Compute secret key | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_set_random_fixed_weight(&sk_seedexpander, x, PARAM_OMEGA); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&sk_seedexpander, y, PARAM_OMEGA); | |||
// Compute public key | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_set_random(&pk_seedexpander, h); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_mul(s, y, h, PARAM_OMEGA); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_add(s, x, s, VEC_N_SIZE_BYTES); | |||
// Parse keys to string | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_public_key_to_string(pk, pk_seed, s); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_secret_key_to_string(sk, sk_seed, pk); | |||
} | |||
/** | |||
* @brief Encryption of the HQC_PKE IND_CPA scheme | |||
* | |||
* The cihertext is composed of vectors <b>u</b> and <b>v</b>. | |||
* | |||
* @param[out] u Vector u (first part of the ciphertext) | |||
* @param[out] v Vector v (second part of the ciphertext) | |||
* @param[in] m Vector representing the message to encrypt | |||
* @param[in] theta Seed used to derive randomness required for encryption | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_pke_encrypt(uint8_t *u, uint8_t *v, const uint8_t *m, const uint8_t *theta, const uint8_t *pk) { | |||
AES_XOF_struct seedexpander; | |||
uint8_t h[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t s[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t r1[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t r2[PARAM_OMEGA_R] = {0}; | |||
uint8_t e[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp1[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp2[VEC_N_SIZE_BYTES] = {0}; | |||
// Create seed_expander from theta | |||
seedexpander_init(&seedexpander, theta, theta + 32, SEEDEXPANDER_MAX_LENGTH); | |||
// Retrieve h and s from public key | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_public_key_from_string(h, s, pk); | |||
// Generate r1, r2 and e | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_set_random_fixed_weight(&seedexpander, r1, PARAM_OMEGA_R); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&seedexpander, r2, PARAM_OMEGA_R); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_set_random_fixed_weight(&seedexpander, e, PARAM_OMEGA_E); | |||
// Compute u = r1 + r2.h | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_mul(u, r2, h, PARAM_OMEGA_R); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_add(u, r1, u, VEC_N_SIZE_BYTES); | |||
// Compute v = m.G by encoding the message | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_tensor_code_encode(v, m); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_resize(tmp1, PARAM_N, v, PARAM_N1N2); | |||
// Compute v = m.G + s.r2 + e | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_mul(tmp2, r2, s, PARAM_OMEGA_R); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_add(tmp2, e, tmp2, VEC_N_SIZE_BYTES); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_add(tmp2, tmp1, tmp2, VEC_N_SIZE_BYTES); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_resize(v, PARAM_N1N2, tmp2, PARAM_N); | |||
} | |||
/** | |||
* @brief Decryption of the HQC_PKE IND_CPA scheme | |||
* | |||
* @param[out] m Vector representing the decrypted message | |||
* @param[in] u Vector u (first part of the ciphertext) | |||
* @param[in] v Vector v (second part of the ciphertext) | |||
* @param[in] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_pke_decrypt(uint8_t *m, const uint8_t *u, const uint8_t *v, const uint8_t *sk) { | |||
uint8_t x[VEC_N_SIZE_BYTES] = {0}; | |||
uint32_t y[PARAM_OMEGA] = {0}; | |||
uint8_t pk[PUBLIC_KEY_BYTES] = {0}; | |||
uint8_t tmp1[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t tmp2[VEC_N_SIZE_BYTES] = {0}; | |||
// Retrieve x, y, pk from secret key | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_secret_key_from_string(x, y, pk, sk); | |||
// Compute v - u.y | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_resize(tmp1, PARAM_N, v, PARAM_N1N2); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_mul(tmp2, y, u, PARAM_OMEGA); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_add(tmp2, tmp1, tmp2, VEC_N_SIZE_BYTES); | |||
// Compute m by decoding v - u.y | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_tensor_code_decode(m, tmp2); | |||
} |
@@ -1,15 +0,0 @@ | |||
#ifndef PQCLEAN_HQC2561CCA2_LEAKTIME_HQC_H | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_HQC_H | |||
/** | |||
* @file hqc.h | |||
* @brief Functions of the HQC_PKE IND_CPA scheme | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_pke_keygen(uint8_t *pk, uint8_t *sk); | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_pke_encrypt(uint8_t *u, uint8_t *v, const uint8_t *m, const uint8_t *theta, const uint8_t *pk); | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_pke_decrypt(uint8_t *m, const uint8_t *u, const uint8_t *v, const uint8_t *sk); | |||
#endif |
@@ -1,154 +0,0 @@ | |||
/** | |||
* @file kem.c | |||
* @brief Implementation of api.h | |||
*/ | |||
#include "api.h" | |||
#include "hqc.h" | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "sha2.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
/** | |||
* @brief Keygen of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b>. | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As a technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[out] sk String containing the secret key | |||
* @returns 0 if keygen is successful | |||
*/ | |||
int PQCLEAN_HQC2561CCA2_LEAKTIME_crypto_kem_keypair(uint8_t *pk, uint8_t *sk) { | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_pke_keygen(pk, sk); | |||
return 0; | |||
} | |||
/** | |||
* @brief Encapsulation of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* @param[out] ct String containing the ciphertext | |||
* @param[out] ss String containing the shared secret | |||
* @param[in] pk String containing the public key | |||
* @returns 0 if encapsulation is successful | |||
*/ | |||
int PQCLEAN_HQC2561CCA2_LEAKTIME_crypto_kem_enc(uint8_t *ct, uint8_t *ss, const uint8_t *pk) { | |||
AES_XOF_struct G_seedexpander; | |||
uint8_t seed_G[VEC_K_SIZE_BYTES]; | |||
uint8_t diversifier_bytes[8] = {0}; | |||
uint8_t m[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t theta[SEED_BYTES] = {0}; | |||
uint8_t u[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d[SHA512_BYTES] = {0}; | |||
uint8_t mc[VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES] = {0}; | |||
// Computing m | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_set_random_from_randombytes(m); | |||
// Generating G function | |||
memcpy(seed_G, m, VEC_K_SIZE_BYTES); | |||
seedexpander_init(&G_seedexpander, seed_G, diversifier_bytes, SEEDEXPANDER_MAX_LENGTH); | |||
// Computing theta | |||
seedexpander(&G_seedexpander, theta, SEED_BYTES); | |||
// Encrypting m | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_pke_encrypt(u, v, m, theta, pk); | |||
// Computing d | |||
sha512(d, m, VEC_K_SIZE_BYTES); | |||
// Computing shared secret | |||
memcpy(mc, m, VEC_K_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES, u, VEC_N_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
sha512(ss, mc, VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES); | |||
// Computing ciphertext | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_ciphertext_to_string(ct, u, v, d); | |||
return 0; | |||
} | |||
/** | |||
* @brief Decapsulation of the HQC_KEM IND_CAA2 scheme | |||
* | |||
* @param[out] ss String containing the shared secret | |||
* @param[in] ct String containing the cipĥertext | |||
* @param[in] sk String containing the secret key | |||
* @returns 0 if decapsulation is successful, -1 otherwise | |||
*/ | |||
int PQCLEAN_HQC2561CCA2_LEAKTIME_crypto_kem_dec(uint8_t *ss, const uint8_t *ct, const uint8_t *sk) { | |||
AES_XOF_struct G_seedexpander; | |||
uint8_t seed_G[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t diversifier_bytes[8] = {0}; | |||
uint8_t u[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d[SHA512_BYTES] = {0}; | |||
uint8_t pk[PUBLIC_KEY_BYTES] = {0}; | |||
uint8_t m[VEC_K_SIZE_BYTES] = {0}; | |||
uint8_t theta[SEED_BYTES] = {0}; | |||
uint8_t u2[VEC_N_SIZE_BYTES] = {0}; | |||
uint8_t v2[VEC_N1N2_SIZE_BYTES] = {0}; | |||
uint8_t d2[SHA512_BYTES] = {0}; | |||
uint8_t mc[VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES] = {0}; | |||
int8_t abort = 0; | |||
// Retrieving u, v and d from ciphertext | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_ciphertext_from_string(u, v, d, ct); | |||
// Retrieving pk from sk | |||
memcpy(pk, sk + SEED_BYTES, PUBLIC_KEY_BYTES); | |||
// Decryting | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_pke_decrypt(m, u, v, sk); | |||
// Generating G function | |||
memcpy(seed_G, m, VEC_K_SIZE_BYTES); | |||
seedexpander_init(&G_seedexpander, seed_G, diversifier_bytes, SEEDEXPANDER_MAX_LENGTH); | |||
// Computing theta | |||
seedexpander(&G_seedexpander, theta, SEED_BYTES); | |||
// Encrypting m' | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_pke_encrypt(u2, v2, m, theta, pk); | |||
// Checking that c = c' and abort otherwise | |||
if (PQCLEAN_HQC2561CCA2_LEAKTIME_vect_compare(u, u2, VEC_N_SIZE_BYTES) != 0 || | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_compare(v, v2, VEC_N1N2_SIZE_BYTES) != 0) { | |||
abort = 1; | |||
} | |||
// Computing d' | |||
sha512(d2, m, VEC_K_SIZE_BYTES); | |||
// Checking that d = d' and abort otherwise | |||
if (memcmp(d, d2, SHA512_BYTES) != 0) { | |||
abort = 1; | |||
} | |||
if (abort == 1) { | |||
memset(ss, 0, SHARED_SECRET_BYTES); | |||
return -1; | |||
} | |||
// Computing shared secret | |||
memcpy(mc, m, VEC_K_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES, u, VEC_N_SIZE_BYTES); | |||
memcpy(mc + VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
sha512(ss, mc, VEC_K_SIZE_BYTES + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES); | |||
return 0; | |||
} |
@@ -1,109 +0,0 @@ | |||
#ifndef PQCLEAN_HQC2561CCA2_LEAKTIME_HQC_PARAMETERS_H | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_HQC_PARAMETERS_H | |||
/** | |||
* @file parameters.h | |||
* @brief Parameters of the HQC_KEM IND-CCA2 scheme | |||
*/ | |||
#include "api.h" | |||
#define CEIL_DIVIDE(a, b) (((a)/(b)) + ((a) % (b) == 0 ? 0 : 1)) /*!< Divide a by b and ceil the result*/ | |||
#define BITMASK(a, size) ((1ULL << ((a) % (size))) - 1) /*!< Create a mask*/ | |||
/* | |||
#define PARAM_N Define the parameter n of the scheme | |||
#define PARAM_N1 Define the parameter n1 of the scheme (length of BCH code) | |||
#define PARAM_N2 Define the parameter n2 of the scheme (length of the repetition code) | |||
#define PARAM_N1N2 Define the parameter n1 * n2 of the scheme (length of the tensor code) | |||
#define PARAM_OMEGA Define the parameter omega of the scheme | |||
#define PARAM_OMEGA_E Define the parameter omega_e of the scheme | |||
#define PARAM_OMEGA_R Define the parameter omega_r of the scheme | |||
#define PARAM_SECURITY Define the security level corresponding to the chosen parameters | |||
#define PARAM_DFR_EXP Define the decryption failure rate corresponding to the chosen parameters | |||
#define SECRET_KEY_BYTES Define the size of the secret key in bytes | |||
#define PUBLIC_KEY_BYTES Define the size of the public key in bytes | |||
#define SHARED_SECRET_BYTES Define the size of the shared secret in bytes | |||
#define CIPHERTEXT_BYTES Define the size of the ciphertext in bytes | |||
#define UTILS_REJECTION_THRESHOLD Define the rejection threshold used to generate given weight vectors (see vector_set_random_fixed_weight function) | |||
#define VEC_N_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N sized vector in bytes | |||
#define VEC_N1_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N1 sized vector in bytes | |||
#define VEC_N1N2_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_N1N2 sized vector in bytes | |||
#define VEC_K_ARRAY_SIZE_BYTES Define the size of the array used to store a PARAM_K sized vector in bytes | |||
#define PARAM_T Define a threshold for decoding repetition code word (PARAM_T = (PARAM_N2 - 1) / 2) | |||
#define PARAM_DELTA Define the parameter delta of the scheme (correcting capacity of the BCH code) | |||
#define PARAM_M Define a positive integer | |||
#define PARAM_GF_MUL_ORDER Define the size of the multiplicative group of GF(2^m), i.e 2^m -1 | |||
#define PARAM_K Define the size of the information bits of the BCH code | |||
#define PARAM_G Define the size of the generator polynomial of BCH code | |||
#define PARAM_FFT The additive FFT takes a 2^PARAM_FFT polynomial as input | |||
We use the FFT to compute the roots of sigma, whose degree if PARAM_DELTA=60 | |||
The smallest power of 2 greater than 60+1 is 64=2^6 | |||
#define PARAM_FFT_T The additive FFT transpose computes a (2^PARAM_FFT_T)-sized syndrome vector | |||
We want to compute 2*PARAM_DELTA=120 syndromes | |||
The smallest power of 2 greater than 120 is 2^7 | |||
#define PARAM_BCH_POLY Generator polynomial of the BCH code | |||
#define SHA512_BYTES Define the size of SHA512 output in bytes | |||
#define SEED_BYTES Define the size of the seed in bytes | |||
#define SEEDEXPANDER_MAX_LENGTH Define the seed expander max length | |||
*/ | |||
#define PARAM_N 63587 | |||
#define PARAM_N1 766 | |||
#define PARAM_N2 83 | |||
#define PARAM_N1N2 63578 | |||
#define PARAM_OMEGA 133 | |||
#define PARAM_OMEGA_E 153 | |||
#define PARAM_OMEGA_R 153 | |||
#define PARAM_SECURITY 256 | |||
#define PARAM_DFR_EXP 128 | |||
#define SECRET_KEY_BYTES PQCLEAN_HQC2561CCA2_LEAKTIME_CRYPTO_SECRETKEYBYTES | |||
#define PUBLIC_KEY_BYTES PQCLEAN_HQC2561CCA2_LEAKTIME_CRYPTO_PUBLICKEYBYTES | |||
#define SHARED_SECRET_BYTES PQCLEAN_HQC2561CCA2_LEAKTIME_CRYPTO_BYTES | |||
#define CIPHERTEXT_BYTES PQCLEAN_HQC2561CCA2_LEAKTIME_CRYPTO_CIPHERTEXTBYTES | |||
#define UTILS_REJECTION_THRESHOLD 16723381 | |||
#define VEC_K_SIZE_BYTES CEIL_DIVIDE(PARAM_K, 8) | |||
#define VEC_N_SIZE_BYTES CEIL_DIVIDE(PARAM_N, 8) | |||
#define VEC_N1_SIZE_BYTES CEIL_DIVIDE(PARAM_N1, 8) | |||
#define VEC_N1N2_SIZE_BYTES CEIL_DIVIDE(PARAM_N1N2, 8) | |||
#define PARAM_T 41 | |||
#define PARAM_DELTA 57 | |||
#define PARAM_M 10 | |||
#define PARAM_GF_MUL_ORDER 1023 | |||
#define PARAM_K 256 | |||
#define PARAM_G 511 | |||
#define PARAM_FFT 6 | |||
#define PARAM_FFT_T 7 | |||
#define PARAM_BCH_POLY { \ | |||
1,1,0,0,0,0,1,0,0,1,1,0,1,1,0,1,0,1,1,0,0,1,0,0,1,1,1,1,1,1,0,0,1,1,0,1,1, \ | |||
1,1,0,1,1,1,1,0,1,0,0,0,1,0,0,1,1,1,0,1,1,0,1,0,1,1,1,0,1,0,1,0,0,1,0,0,0, \ | |||
0,1,1,1,1,0,1,1,1,1,1,0,0,0,0,1,0,0,1,0,0,1,1,1,0,0,0,1,1,0,0,1,0,1,0,0,0, \ | |||
1,0,0,0,0,1,0,0,0,1,0,1,1,0,0,0,0,1,1,0,0,1,1,0,1,0,1,0,1,0,1,1,1,1,0,1,0, \ | |||
0,1,1,0,1,0,1,1,0,0,1,1,0,1,1,1,1,1,0,1,0,1,1,1,0,1,0,0,0,1,1,0,1,1,1,1,0, \ | |||
1,1,1,1,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,1,1,1,1,0,0,1,1,0,1,0,0,0,0,1,0, \ | |||
0,1,0,0,1,0,1,0,0,1,1,0,1,0,1,1,1,1,1,0,1,1,0,1,0,1,1,1,1,1,1,0,0,0,1,0,1, \ | |||
1,1,1,1,1,0,1,0,1,0,1,1,0,0,0,1,1,0,0,1,1,0,1,1,1,1,1,1,1,0,0,0,1,1,1,1,0, \ | |||
1,0,0,0,1,0,0,1,1,0,1,1,0,0,1,0,1,1,0,1,0,1,0,1,1,0,0,0,0,0,1,1,1,1,1,1,1, \ | |||
1,1,1,0,1,1,0,1,0,1,1,1,1,1,1,1,0,1,1,0,1,1,0,0,0,1,0,0,1,1,1,1,1,0,1,0,1, \ | |||
0,0,0,0,1,0,1,1,1,1,0,1,0,0,0,0,0,1,0,0,1,0,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1, \ | |||
1,0,1,0,0,1,0,0,1,1,0,1,0,0,0,0,0,0,0,0,1,1,0,0,0,1,1,1,0,0,1,1,0,0,0,1,1, \ | |||
0,1,0,0,1,0,0,0,1,0,1,0,1,0,0,0,1,1,1,1,1,0,0,0,1,0,0,1,1,0,1,1,0,0,1,0,1, \ | |||
1,0,1,1,1,0,0,0,0,1,1,0,1,1,1,0,1,0,0,0,0,1,0,0,0,1,0,0,1,1 \ | |||
}; | |||
#define SHA512_BYTES 64 | |||
#define SEED_BYTES 40 | |||
#define SEEDEXPANDER_MAX_LENGTH 4294967295 | |||
#endif |
@@ -1,126 +0,0 @@ | |||
/** | |||
* @file parsing.c | |||
* @brief Functions to parse secret key, public key and ciphertext of the HQC scheme | |||
*/ | |||
#include "nistseedexpander.h" | |||
#include "parameters.h" | |||
#include "parsing.h" | |||
#include "vector.h" | |||
#include <stdint.h> | |||
#include <string.h> | |||
/** | |||
* @brief Parse a secret key into a string | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] sk String containing the secret key | |||
* @param[in] sk_seed Seed used to generate the secret key | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_secret_key_to_string(uint8_t *sk, const uint8_t *sk_seed, const uint8_t *pk) { | |||
memcpy(sk, sk_seed, SEED_BYTES); | |||
memcpy(sk + SEED_BYTES, pk, PUBLIC_KEY_BYTES); | |||
} | |||
/** | |||
* @brief Parse a secret key from a string | |||
* | |||
* The secret key is composed of the seed used to generate vectors <b>x</b> and <b>y</b>. | |||
* As technicality, the public key is appended to the secret key in order to respect NIST API. | |||
* | |||
* @param[out] x uint8_t representation of vector x | |||
* @param[out] y uint8_t representation of vector y | |||
* @param[out] pk String containing the public key | |||
* @param[in] sk String containing the secret key | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_secret_key_from_string(uint8_t *x, uint32_t *y, uint8_t *pk, const uint8_t *sk) { | |||
AES_XOF_struct sk_seedexpander; | |||
uint8_t sk_seed[SEED_BYTES] = {0}; | |||
memcpy(sk_seed, sk, SEED_BYTES); | |||
seedexpander_init(&sk_seedexpander, sk_seed, sk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_set_random_fixed_weight(&sk_seedexpander, x, PARAM_OMEGA); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_set_random_fixed_weight_by_coordinates(&sk_seedexpander, y, PARAM_OMEGA); | |||
memcpy(pk, sk + SEED_BYTES, PUBLIC_KEY_BYTES); | |||
} | |||
/** | |||
* @brief Parse a public key into a string | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b> | |||
* | |||
* @param[out] pk String containing the public key | |||
* @param[in] pk_seed Seed used to generate the public key | |||
* @param[in] s uint8_t representation of vector s | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_public_key_to_string(uint8_t *pk, const uint8_t *pk_seed, const uint8_t *s) { | |||
memcpy(pk, pk_seed, SEED_BYTES); | |||
memcpy(pk + SEED_BYTES, s, VEC_N_SIZE_BYTES); | |||
} | |||
/** | |||
* @brief Parse a public key from a string | |||
* | |||
* The public key is composed of the syndrome <b>s</b> as well as the seed used to generate the vector <b>h</b> | |||
* | |||
* @param[out] h uint8_t representation of vector h | |||
* @param[out] s uint8_t representation of vector s | |||
* @param[in] pk String containing the public key | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_public_key_from_string(uint8_t *h, uint8_t *s, const uint8_t *pk) { | |||
AES_XOF_struct pk_seedexpander; | |||
uint8_t pk_seed[SEED_BYTES] = {0}; | |||
memcpy(pk_seed, pk, SEED_BYTES); | |||
seedexpander_init(&pk_seedexpander, pk_seed, pk_seed + 32, SEEDEXPANDER_MAX_LENGTH); | |||
PQCLEAN_HQC2561CCA2_LEAKTIME_vect_set_random(&pk_seedexpander, h); | |||
memcpy(s, pk + SEED_BYTES, VEC_N_SIZE_BYTES); | |||
} | |||
/** | |||
* @brief Parse a ciphertext into a string | |||
* | |||
* The ciphertext is composed of vectors <b>u</b>, <b>v</b> and hash <b>d</b>. | |||
* | |||
* @param[out] ct String containing the ciphertext | |||
* @param[in] u uint8_t representation of vector u | |||
* @param[in] v uint8_t representation of vector v | |||
* @param[in] d String containing the hash d | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_ciphertext_to_string(uint8_t *ct, const uint8_t *u, const uint8_t *v, const uint8_t *d) { | |||
memcpy(ct, u, VEC_N_SIZE_BYTES); | |||
memcpy(ct + VEC_N_SIZE_BYTES, v, VEC_N1N2_SIZE_BYTES); | |||
memcpy(ct + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES, d, SHA512_BYTES); | |||
} | |||
/** | |||
* @brief Parse a ciphertext from a string | |||
* | |||
* The ciphertext is composed of vectors <b>u</b>, <b>v</b> and hash <b>d</b>. | |||
* | |||
* @param[out] u uint8_t representation of vector u | |||
* @param[out] v uint8_t representation of vector v | |||
* @param[out] d String containing the hash d | |||
* @param[in] ct String containing the ciphertext | |||
*/ | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_ciphertext_from_string(uint8_t *u, uint8_t *v, uint8_t *d, const uint8_t *ct) { | |||
memcpy(u, ct, VEC_N_SIZE_BYTES); | |||
memcpy(v, ct + VEC_N_SIZE_BYTES, VEC_N1N2_SIZE_BYTES); | |||
memcpy(d, ct + VEC_N_SIZE_BYTES + VEC_N1N2_SIZE_BYTES, SHA512_BYTES); | |||
} |
@@ -1,20 +0,0 @@ | |||
#ifndef PQCLEAN_HQC2561CCA2_LEAKTIME_PARSING_H | |||
#define PQCLEAN_HQC2561CCA2_LEAKTIME_PARSING_H | |||
/** | |||
* @file parsing.h | |||
* @brief Header file for parsing.c | |||
*/ | |||
#include <stdint.h> | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_secret_key_to_string(uint8_t *sk, const uint8_t *sk_seed, const uint8_t *pk); | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_secret_key_from_string(uint8_t *x, uint32_t *y, uint8_t *pk, const uint8_t *sk); | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_public_key_to_string(uint8_t *pk, const uint8_t *pk_seed, const uint8_t *s); | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_public_key_from_string(uint8_t *h, uint8_t *s, const uint8_t *pk); | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_ciphertext_to_string(uint8_t *ct, const uint8_t *u, const uint8_t *v, const uint8_t *d); | |||
void PQCLEAN_HQC2561CCA2_LEAKTIME_hqc_ciphertext_from_string(uint8_t *u, uint8_t *v, uint8_t *d, const uint8_t *ct); | |||
#endif |