pqc/crypto_kem/kyber768/clean/polyvec.c
2019-02-27 09:18:38 +01:00

163 lines
7.2 KiB
C

#include "polyvec.h"
#include "cbd.h"
#include "fips202.h"
#include "reduce.h"
#include <stdio.h>
/*************************************************
* Name: polyvec_compress
*
* Description: Compress and serialize vector of polynomials
*
* Arguments: - unsigned char *r: pointer to output byte array
* - const polyvec *a: pointer to input vector of polynomials
**************************************************/
void PQCLEAN_KYBER768_CLEAN_polyvec_compress(unsigned char *r, const polyvec *a) {
int i, j, k;
uint16_t t[8];
for (i = 0; i < KYBER_K; i++) {
for (j = 0; j < KYBER_N / 8; j++) {
for (k = 0; k < 8; k++) {
t[k] = ((((uint32_t)PQCLEAN_KYBER768_CLEAN_freeze(a->vec[i].coeffs[8 * j + k]) << 11) + KYBER_Q / 2) / KYBER_Q) & 0x7ff;
}
r[11 * j + 0] = (unsigned char)( t[0] & 0xff);
r[11 * j + 1] = (unsigned char)((t[0] >> 8) | ((t[1] & 0x1f) << 3));
r[11 * j + 2] = (unsigned char)((t[1] >> 5) | ((t[2] & 0x03) << 6));
r[11 * j + 3] = (unsigned char)((t[2] >> 2) & 0xff);
r[11 * j + 4] = (unsigned char)((t[2] >> 10) | ((t[3] & 0x7f) << 1));
r[11 * j + 5] = (unsigned char)((t[3] >> 7) | ((t[4] & 0x0f) << 4));
r[11 * j + 6] = (unsigned char)((t[4] >> 4) | ((t[5] & 0x01) << 7));
r[11 * j + 7] = (unsigned char)((t[5] >> 1) & 0xff);
r[11 * j + 8] = (unsigned char)((t[5] >> 9) | ((t[6] & 0x3f) << 2));
r[11 * j + 9] = (unsigned char)((t[6] >> 6) | ((t[7] & 0x07) << 5));
r[11 * j + 10] = (unsigned char)((t[7] >> 3));
}
r += 352;
}
}
/*************************************************
* Name: polyvec_decompress
*
* Description: De-serialize and decompress vector of polynomials;
* approximate inverse of polyvec_compress
*
* Arguments: - polyvec *r: pointer to output vector of polynomials
* - unsigned char *a: pointer to input byte array
**************************************************/
void PQCLEAN_KYBER768_CLEAN_polyvec_decompress(polyvec *r, const unsigned char *a) {
int i, j;
for (i = 0; i < KYBER_K; i++) {
for (j = 0; j < KYBER_N / 8; j++) {
r->vec[i].coeffs[8 * j + 0] = (((a[11 * j + 0] | (((uint32_t)a[11 * j + 1] & 0x07) << 8)) * KYBER_Q) + 1024) >> 11;
r->vec[i].coeffs[8 * j + 1] = ((((a[11 * j + 1] >> 3) | (((uint32_t)a[11 * j + 2] & 0x3f) << 5)) * KYBER_Q) + 1024) >> 11;
r->vec[i].coeffs[8 * j + 2] = ((((a[11 * j + 2] >> 6) | (((uint32_t)a[11 * j + 3] & 0xff) << 2) | (((uint32_t)a[11 * j + 4] & 0x01) << 10)) * KYBER_Q) + 1024) >> 11;
r->vec[i].coeffs[8 * j + 3] = ((((a[11 * j + 4] >> 1) | (((uint32_t)a[11 * j + 5] & 0x0f) << 7)) * KYBER_Q) + 1024) >> 11;
r->vec[i].coeffs[8 * j + 4] = ((((a[11 * j + 5] >> 4) | (((uint32_t)a[11 * j + 6] & 0x7f) << 4)) * KYBER_Q) + 1024) >> 11;
r->vec[i].coeffs[8 * j + 5] = ((((a[11 * j + 6] >> 7) | (((uint32_t)a[11 * j + 7] & 0xff) << 1) | (((uint32_t)a[11 * j + 8] & 0x03) << 9)) * KYBER_Q) + 1024) >> 11;
r->vec[i].coeffs[8 * j + 6] = ((((a[11 * j + 8] >> 2) | (((uint32_t)a[11 * j + 9] & 0x1f) << 6)) * KYBER_Q) + 1024) >> 11;
r->vec[i].coeffs[8 * j + 7] = ((((a[11 * j + 9] >> 5) | (((uint32_t)a[11 * j + 10] & 0xff) << 3)) * KYBER_Q) + 1024) >> 11;
}
a += 352;
}
}
/*************************************************
* Name: polyvec_tobytes
*
* Description: Serialize vector of polynomials
*
* Arguments: - unsigned char *r: pointer to output byte array
* - const polyvec *a: pointer to input vector of polynomials
**************************************************/
void PQCLEAN_KYBER768_CLEAN_polyvec_tobytes(unsigned char *r, const polyvec *a) {
int i;
for (i = 0; i < KYBER_K; i++) {
PQCLEAN_KYBER768_CLEAN_poly_tobytes(r + i * KYBER_POLYBYTES, &a->vec[i]);
}
}
/*************************************************
* Name: polyvec_frombytes
*
* Description: De-serialize vector of polynomials;
* inverse of polyvec_tobytes
*
* Arguments: - unsigned char *r: pointer to output byte array
* - const polyvec *a: pointer to input vector of polynomials
**************************************************/
void PQCLEAN_KYBER768_CLEAN_polyvec_frombytes(polyvec *r, const unsigned char *a) {
int i;
for (i = 0; i < KYBER_K; i++) {
PQCLEAN_KYBER768_CLEAN_poly_frombytes(&r->vec[i], a + i * KYBER_POLYBYTES);
}
}
/*************************************************
* Name: polyvec_ntt
*
* Description: Apply forward NTT to all elements of a vector of polynomials
*
* Arguments: - polyvec *r: pointer to in/output vector of polynomials
**************************************************/
void PQCLEAN_KYBER768_CLEAN_polyvec_ntt(polyvec *r) {
int i;
for (i = 0; i < KYBER_K; i++) {
PQCLEAN_KYBER768_CLEAN_poly_ntt(&r->vec[i]);
}
}
/*************************************************
* Name: polyvec_invntt
*
* Description: Apply inverse NTT to all elements of a vector of polynomials
*
* Arguments: - polyvec *r: pointer to in/output vector of polynomials
**************************************************/
void PQCLEAN_KYBER768_CLEAN_polyvec_invntt(polyvec *r) {
int i;
for (i = 0; i < KYBER_K; i++) {
PQCLEAN_KYBER768_CLEAN_poly_invntt(&r->vec[i]);
}
}
/*************************************************
* Name: polyvec_pointwise_acc
*
* Description: Pointwise multiply elements of a and b and accumulate into r
*
* Arguments: - poly *r: pointer to output polynomial
* - const polyvec *a: pointer to first input vector of polynomials
* - const polyvec *b: pointer to second input vector of polynomials
**************************************************/
void PQCLEAN_KYBER768_CLEAN_polyvec_pointwise_acc(poly *r, const polyvec *a, const polyvec *b) {
int i, j;
uint16_t t;
for (j = 0; j < KYBER_N; j++) {
t = PQCLEAN_KYBER768_CLEAN_montgomery_reduce(4613 * (uint32_t)b->vec[0].coeffs[j]); // 4613 = 2^{2*18} % q
r->coeffs[j] = PQCLEAN_KYBER768_CLEAN_montgomery_reduce(a->vec[0].coeffs[j] * t);
for (i = 1; i < KYBER_K; i++) {
t = PQCLEAN_KYBER768_CLEAN_montgomery_reduce(4613 * (uint32_t)b->vec[i].coeffs[j]);
r->coeffs[j] += PQCLEAN_KYBER768_CLEAN_montgomery_reduce(a->vec[i].coeffs[j] * t);
}
r->coeffs[j] = PQCLEAN_KYBER768_CLEAN_barrett_reduce(r->coeffs[j]);
}
}
/*************************************************
* Name: polyvec_add
*
* Description: Add vectors of polynomials
*
* Arguments: - polyvec *r: pointer to output vector of polynomials
* - const polyvec *a: pointer to first input vector of polynomials
* - const polyvec *b: pointer to second input vector of polynomials
**************************************************/
void PQCLEAN_KYBER768_CLEAN_polyvec_add(polyvec *r, const polyvec *a, const polyvec *b) {
int i;
for (i = 0; i < KYBER_K; i++) {
PQCLEAN_KYBER768_CLEAN_poly_add(&r->vec[i], &a->vec[i], &b->vec[i]);
}
}