778 lines
28 KiB
C
778 lines
28 KiB
C
#include "poly.h"
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#include "fips202.h"
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#include "ntt.h"
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#include "params.h"
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#include "reduce.h"
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#include "rounding.h"
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#include <stdint.h>
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/*************************************************
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* Name: poly_reduce
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*
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* Description: Reduce all coefficients of input polynomial to representative
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* in [0,2*Q[.
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*
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* Arguments: - poly *a: pointer to input/output polynomial
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_reduce(poly *a) {
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unsigned int i;
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for (i = 0; i < N; ++i) {
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a->coeffs[i] = PQCLEAN_DILITHIUMIII_CLEAN_reduce32(a->coeffs[i]);
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}
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}
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/*************************************************
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* Name: poly_csubq
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*
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* Description: For all coefficients of input polynomial subtract Q if
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* coefficient is bigger than Q.
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*
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* Arguments: - poly *a: pointer to input/output polynomial
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_csubq(poly *a) {
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unsigned int i;
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for (i = 0; i < N; ++i) {
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a->coeffs[i] = PQCLEAN_DILITHIUMIII_CLEAN_csubq(a->coeffs[i]);
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}
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}
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/*************************************************
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* Name: poly_freeze
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*
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* Description: Reduce all coefficients of the polynomial to standard
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* representatives.
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*
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* Arguments: - poly *a: pointer to input/output polynomial
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_freeze(poly *a) {
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unsigned int i;
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for (i = 0; i < N; ++i) {
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a->coeffs[i] = PQCLEAN_DILITHIUMIII_CLEAN_freeze(a->coeffs[i]);
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}
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}
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/*************************************************
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* Name: poly_add
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*
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* Description: Add polynomials. No modular reduction is performed.
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*
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* Arguments: - poly *c: pointer to output polynomial
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* - const poly *a: pointer to first summand
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* - const poly *b: pointer to second summand
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_add(poly *c, const poly *a, const poly *b) {
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unsigned int i;
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for (i = 0; i < N; ++i) {
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c->coeffs[i] = a->coeffs[i] + b->coeffs[i];
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}
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}
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/*************************************************
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* Name: poly_sub
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*
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* Description: Subtract polynomials. Assumes coefficients of second input
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* polynomial to be less than 2*Q. No modular reduction is
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* performed.
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*
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* Arguments: - poly *c: pointer to output polynomial
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* - const poly *a: pointer to first input polynomial
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* - const poly *b: pointer to second input polynomial to be
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* subtraced from first input polynomial
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_sub(poly *c, const poly *a, const poly *b) {
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unsigned int i;
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for (i = 0; i < N; ++i) {
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c->coeffs[i] = a->coeffs[i] + 2 * Q - b->coeffs[i];
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}
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}
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/*************************************************
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* Name: poly_neg
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*
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* Description: Negate polynomial. Assumes input coefficients to be standard
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* representatives.
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*
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* Arguments: - poly *a: pointer to input/output polynomial
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_neg(poly *a) {
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unsigned int i;
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for (i = 0; i < N; ++i) {
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a->coeffs[i] = Q - a->coeffs[i];
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}
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}
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/*************************************************
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* Name: poly_shiftl
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*
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* Description: Multiply polynomial by 2^k without modular reduction. Assumes
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* input coefficients to be less than 2^{32-k}.
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*
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* Arguments: - poly *a: pointer to input/output polynomial
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* - unsigned int k: exponent
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_shiftl(poly *a, unsigned int k) {
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unsigned int i;
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for (i = 0; i < N; ++i) {
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a->coeffs[i] <<= k;
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}
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}
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/*************************************************
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* Name: poly_ntt
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*
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* Description: Forward NTT. Output coefficients can be up to 16*Q larger than
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* input coefficients.
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*
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* Arguments: - poly *a: pointer to input/output polynomial
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_ntt(poly *a) {
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PQCLEAN_DILITHIUMIII_CLEAN_ntt(a->coeffs);
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}
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/*************************************************
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* Name: poly_invntt_montgomery
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*
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* Description: Inverse NTT and multiplication with 2^{32}. Input coefficients
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* need to be less than 2*Q. Output coefficients are less than 2*Q.
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*
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* Arguments: - poly *a: pointer to input/output polynomial
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_invntt_montgomery(poly *a) {
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PQCLEAN_DILITHIUMIII_CLEAN_invntt_frominvmont(a->coeffs);
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}
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/*************************************************
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* Name: poly_pointwise_invmontgomery
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*
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* Description: Pointwise multiplication of polynomials in NTT domain
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* representation and multiplication of resulting polynomial
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* with 2^{-32}. Output coefficients are less than 2*Q if input
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* coefficient are less than 22*Q.
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*
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* Arguments: - poly *c: pointer to output polynomial
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* - const poly *a: pointer to first input polynomial
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* - const poly *b: pointer to second input polynomial
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_pointwise_invmontgomery(poly *c, const poly *a,
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const poly *b) {
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unsigned int i;
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for (i = 0; i < N; ++i) {
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c->coeffs[i] = PQCLEAN_DILITHIUMIII_CLEAN_montgomery_reduce(
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(uint64_t)a->coeffs[i] * b->coeffs[i]);
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}
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}
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/*************************************************
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* Name: poly_power2round
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*
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* Description: For all coefficients c of the input polynomial,
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* compute c0, c1 such that c mod Q = c1*2^D + c0
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* with -2^{D-1} < c0 <= 2^{D-1}. Assumes coefficients to be
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* standard representatives.
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*
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* Arguments: - poly *a1: pointer to output polynomial with coefficients c1
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* - poly *a0: pointer to output polynomial with coefficients Q +
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*a0
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* - const poly *v: pointer to input polynomial
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_power2round(poly *a1, poly *a0, const poly *a) {
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unsigned int i;
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for (i = 0; i < N; ++i) {
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a1->coeffs[i] =
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PQCLEAN_DILITHIUMIII_CLEAN_power2round(a->coeffs[i], a0->coeffs + i);
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}
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}
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/*************************************************
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* Name: poly_decompose
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*
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* Description: For all coefficients c of the input polynomial,
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* compute high and low bits c0, c1 such c mod Q = c1*ALPHA + c0
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* with -ALPHA/2 < c0 <= ALPHA/2 except c1 = (Q-1)/ALPHA where we
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* set c1 = 0 and -ALPHA/2 <= c0 = c mod Q - Q < 0.
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* Assumes coefficients to be standard representatives.
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*
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* Arguments: - poly *a1: pointer to output polynomial with coefficients c1
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* - poly *a0: pointer to output polynomial with coefficients Q +
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*a0
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* - const poly *c: pointer to input polynomial
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_decompose(poly *a1, poly *a0, const poly *a) {
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unsigned int i;
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for (i = 0; i < N; ++i) {
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a1->coeffs[i] =
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PQCLEAN_DILITHIUMIII_CLEAN_decompose(a->coeffs[i], a0->coeffs + i);
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}
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}
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/*************************************************
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* Name: poly_make_hint
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*
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* Description: Compute hint polynomial. The coefficients of which indicate
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* whether the high bits of the corresponding coefficients
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* of the first input polynomial and of the sum of the input
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* polynomials differ.
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*
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* Arguments: - poly *h: pointer to output hint polynomial
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* - const poly *a: pointer to first input polynomial
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* - const poly *b: pointer to second input polynomial
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*
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* Returns number of 1 bits.
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**************************************************/
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unsigned int PQCLEAN_DILITHIUMIII_CLEAN_poly_make_hint(poly *h, const poly *a,
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const poly *b) {
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unsigned int i, s = 0;
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for (i = 0; i < N; ++i) {
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h->coeffs[i] =
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PQCLEAN_DILITHIUMIII_CLEAN_make_hint(a->coeffs[i], b->coeffs[i]);
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s += h->coeffs[i];
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}
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return s;
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}
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/*************************************************
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* Name: poly_use_hint
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*
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* Description: Use hint polynomial to correct the high bits of a polynomial.
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*
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* Arguments: - poly *a: pointer to output polynomial with corrected high bits
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* - const poly *b: pointer to input polynomial
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* - const poly *h: pointer to input hint polynomial
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_use_hint(poly *a, const poly *b, const poly *h) {
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unsigned int i;
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for (i = 0; i < N; ++i) {
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a->coeffs[i] =
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PQCLEAN_DILITHIUMIII_CLEAN_use_hint(b->coeffs[i], h->coeffs[i]);
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}
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}
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/*************************************************
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* Name: poly_chknorm
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*
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* Description: Check infinity norm of polynomial against given bound.
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* Assumes input coefficients to be standard representatives.
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*
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* Arguments: - const poly *a: pointer to polynomial
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* - uint32_t B: norm bound
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*
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* Returns 0 if norm is strictly smaller than B and 1 otherwise.
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**************************************************/
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int PQCLEAN_DILITHIUMIII_CLEAN_poly_chknorm(const poly *a, uint32_t B) {
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unsigned int i;
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int32_t t;
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/* It is ok to leak which coefficient violates the bound since
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the probability for each coefficient is independent of secret
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data but we must not leak the sign of the centralized representative. */
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for (i = 0; i < N; ++i) {
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/* Absolute value of centralized representative */
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t = (Q - 1) / 2 - a->coeffs[i];
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t ^= (t >> 31);
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t = (Q - 1) / 2 - t;
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if ((uint32_t)t >= B) {
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return 1;
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}
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}
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return 0;
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}
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/*************************************************
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* Name: poly_uniform
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*
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* Description: Sample uniformly random polynomial using stream of random bytes.
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* Assumes that enough random bytes are given (e.g.
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* 5*SHAKE128_RATE bytes).
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*
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* Arguments: - poly *a: pointer to output polynomial
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* - const unsigned char *buf: array of random bytes
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_uniform(poly *a, const unsigned char *buf) {
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unsigned int ctr, pos;
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uint32_t t;
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ctr = pos = 0;
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while (ctr < N) {
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t = buf[pos++];
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t |= (uint32_t)buf[pos++] << 8;
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t |= (uint32_t)buf[pos++] << 16;
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t &= 0x7FFFFF;
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if (t < Q) {
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a->coeffs[ctr++] = t;
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}
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}
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}
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/*************************************************
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* Name: rej_eta
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*
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* Description: Sample uniformly random coefficients in [-ETA, ETA] by
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* performing rejection sampling using array of random bytes.
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*
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* Arguments: - uint32_t *a: pointer to output array (allocated)
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* - unsigned int len: number of coefficients to be sampled
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* - const unsigned char *buf: array of random bytes
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* - unsigned int buflen: length of array of random bytes
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*
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* Returns number of sampled coefficients. Can be smaller than len if not enough
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* random bytes were given.
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**************************************************/
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static unsigned int rej_eta(uint32_t *a, unsigned int len,
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const unsigned char *buf, unsigned int buflen) {
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#if ETA > 7
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#error "rej_eta() assumes ETA <= 7"
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#endif
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unsigned int ctr, pos;
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unsigned char t0, t1;
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ctr = pos = 0;
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while (ctr < len && pos < buflen) {
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#if ETA <= 3
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t0 = buf[pos] & 0x07;
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t1 = buf[pos++] >> 5;
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#else
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t0 = buf[pos] & 0x0F;
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t1 = buf[pos++] >> 4;
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#endif
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if (t0 <= 2 * ETA) {
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a[ctr++] = Q + ETA - t0;
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}
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if (t1 <= 2 * ETA && ctr < len) {
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a[ctr++] = Q + ETA - t1;
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}
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}
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return ctr;
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}
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/*************************************************
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* Name: poly_uniform_eta
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*
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* Description: Sample polynomial with uniformly random coefficients
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* in [-ETA,ETA] by performing rejection sampling using the
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* output stream from SHAKE256(seed|nonce).
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*
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* Arguments: - poly *a: pointer to output polynomial
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* - const unsigned char seed[]: byte array with seed of length
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* SEEDBYTES
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* - unsigned char nonce: nonce byte
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_uniform_eta(poly *a,
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const unsigned char seed[SEEDBYTES],
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unsigned char nonce) {
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unsigned int i, ctr;
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unsigned char inbuf[SEEDBYTES + 1];
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/* Probability that we need more than 2 blocks: < 2^{-84}
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Probability that we need more than 3 blocks: < 2^{-352} */
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unsigned char outbuf[2 * SHAKE256_RATE];
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uint64_t state[25];
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for (i = 0; i < SEEDBYTES; ++i) {
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inbuf[i] = seed[i];
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}
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inbuf[SEEDBYTES] = nonce;
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shake256_absorb(state, inbuf, SEEDBYTES + 1);
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shake256_squeezeblocks(outbuf, 2, state);
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ctr = rej_eta(a->coeffs, N, outbuf, 2 * SHAKE256_RATE);
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if (ctr < N) {
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shake256_squeezeblocks(outbuf, 1, state);
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rej_eta(a->coeffs + ctr, N - ctr, outbuf, SHAKE256_RATE);
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}
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}
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/*************************************************
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* Name: rej_gamma1m1
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*
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* Description: Sample uniformly random coefficients
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* in [-(GAMMA1 - 1), GAMMA1 - 1] by performing rejection sampling
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* using array of random bytes.
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*
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* Arguments: - uint32_t *a: pointer to output array (allocated)
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* - unsigned int len: number of coefficients to be sampled
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* - const unsigned char *buf: array of random bytes
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* - unsigned int buflen: length of array of random bytes
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*
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* Returns number of sampled coefficients. Can be smaller than len if not enough
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* random bytes were given.
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**************************************************/
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static unsigned int rej_gamma1m1(uint32_t *a, unsigned int len,
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const unsigned char *buf,
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unsigned int buflen) {
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#if GAMMA1 > (1 << 19)
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#error "rej_gamma1m1() assumes GAMMA1 - 1 fits in 19 bits"
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#endif
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unsigned int ctr, pos;
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uint32_t t0, t1;
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ctr = pos = 0;
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while (ctr < len && pos + 5 <= buflen) {
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t0 = buf[pos];
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t0 |= (uint32_t)buf[pos + 1] << 8;
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t0 |= (uint32_t)buf[pos + 2] << 16;
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t0 &= 0xFFFFF;
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t1 = buf[pos + 2] >> 4;
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t1 |= (uint32_t)buf[pos + 3] << 4;
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t1 |= (uint32_t)buf[pos + 4] << 12;
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pos += 5;
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if (t0 <= 2 * GAMMA1 - 2) {
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a[ctr++] = Q + GAMMA1 - 1 - t0;
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}
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if (t1 <= 2 * GAMMA1 - 2 && ctr < len) {
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a[ctr++] = Q + GAMMA1 - 1 - t1;
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}
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}
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return ctr;
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}
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/*************************************************
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* Name: poly_uniform_gamma1m1
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*
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* Description: Sample polynomial with uniformly random coefficients
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* in [-(GAMMA1 - 1), GAMMA1 - 1] by performing rejection
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* sampling on output stream of SHAKE256(seed|nonce).
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*
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* Arguments: - poly *a: pointer to output polynomial
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* - const unsigned char seed[]: byte array with seed of length
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* SEEDBYTES + CRHBYTES
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* - uint16_t nonce: 16-bit nonce
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**************************************************/
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void PQCLEAN_DILITHIUMIII_CLEAN_poly_uniform_gamma1m1(
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poly *a, const unsigned char seed[SEEDBYTES + CRHBYTES], uint16_t nonce) {
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unsigned int i, ctr;
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unsigned char inbuf[SEEDBYTES + CRHBYTES + 2];
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/* Probability that we need more than 5 blocks: < 2^{-81}
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Probability that we need more than 6 blocks: < 2^{-467} */
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unsigned char outbuf[5 * SHAKE256_RATE];
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uint64_t state[25];
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for (i = 0; i < SEEDBYTES + CRHBYTES; ++i) {
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inbuf[i] = seed[i];
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}
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inbuf[SEEDBYTES + CRHBYTES] = nonce & 0xFF;
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inbuf[SEEDBYTES + CRHBYTES + 1] = nonce >> 8;
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shake256_absorb(state, inbuf, SEEDBYTES + CRHBYTES + 2);
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shake256_squeezeblocks(outbuf, 5, state);
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ctr = rej_gamma1m1(a->coeffs, N, outbuf, 5 * SHAKE256_RATE);
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if (ctr < N) {
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/* There are no bytes left in outbuf
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since 5*SHAKE256_RATE is divisible by 5 */
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shake256_squeezeblocks(outbuf, 1, state);
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rej_gamma1m1(a->coeffs + ctr, N - ctr, outbuf, SHAKE256_RATE);
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}
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}
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/*************************************************
|
|
* Name: polyeta_pack
|
|
*
|
|
* Description: Bit-pack polynomial with coefficients in [-ETA,ETA].
|
|
* Input coefficients are assumed to lie in [Q-ETA,Q+ETA].
|
|
*
|
|
* Arguments: - unsigned char *r: pointer to output byte array with at least
|
|
* POLETA_SIZE_PACKED bytes
|
|
* - const poly *a: pointer to input polynomial
|
|
**************************************************/
|
|
void PQCLEAN_DILITHIUMIII_CLEAN_polyeta_pack(unsigned char *r, const poly *a) {
|
|
#if ETA > 7
|
|
#error "polyeta_pack() assumes ETA <= 7"
|
|
#endif
|
|
unsigned int i;
|
|
unsigned char t[8];
|
|
|
|
#if ETA <= 3
|
|
for (i = 0; i < N / 8; ++i) {
|
|
t[0] = Q + ETA - a->coeffs[8 * i + 0];
|
|
t[1] = Q + ETA - a->coeffs[8 * i + 1];
|
|
t[2] = Q + ETA - a->coeffs[8 * i + 2];
|
|
t[3] = Q + ETA - a->coeffs[8 * i + 3];
|
|
t[4] = Q + ETA - a->coeffs[8 * i + 4];
|
|
t[5] = Q + ETA - a->coeffs[8 * i + 5];
|
|
t[6] = Q + ETA - a->coeffs[8 * i + 6];
|
|
t[7] = Q + ETA - a->coeffs[8 * i + 7];
|
|
|
|
r[3 * i + 0] = t[0];
|
|
r[3 * i + 0] |= t[1] << 3;
|
|
r[3 * i + 0] |= t[2] << 6;
|
|
r[3 * i + 1] = t[2] >> 2;
|
|
r[3 * i + 1] |= t[3] << 1;
|
|
r[3 * i + 1] |= t[4] << 4;
|
|
r[3 * i + 1] |= t[5] << 7;
|
|
r[3 * i + 2] = t[5] >> 1;
|
|
r[3 * i + 2] |= t[6] << 2;
|
|
r[3 * i + 2] |= t[7] << 5;
|
|
}
|
|
#else
|
|
for (i = 0; i < N / 2; ++i) {
|
|
t[0] = Q + ETA - a->coeffs[2 * i + 0];
|
|
t[1] = Q + ETA - a->coeffs[2 * i + 1];
|
|
r[i] = t[0] | (t[1] << 4);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*************************************************
|
|
* Name: polyeta_unpack
|
|
*
|
|
* Description: Unpack polynomial with coefficients in [-ETA,ETA].
|
|
* Output coefficients lie in [Q-ETA,Q+ETA].
|
|
*
|
|
* Arguments: - poly *r: pointer to output polynomial
|
|
* - const unsigned char *a: byte array with bit-packed polynomial
|
|
**************************************************/
|
|
void PQCLEAN_DILITHIUMIII_CLEAN_polyeta_unpack(poly *r, const unsigned char *a) {
|
|
unsigned int i;
|
|
|
|
#if ETA <= 3
|
|
for (i = 0; i < N / 8; ++i) {
|
|
r->coeffs[8 * i + 0] = a[3 * i + 0] & 0x07;
|
|
r->coeffs[8 * i + 1] = (a[3 * i + 0] >> 3) & 0x07;
|
|
r->coeffs[8 * i + 2] =
|
|
(a[3 * i + 0] >> 6) | ((a[3 * i + 1] & 0x01) << 2);
|
|
r->coeffs[8 * i + 3] = (a[3 * i + 1] >> 1) & 0x07;
|
|
r->coeffs[8 * i + 4] = (a[3 * i + 1] >> 4) & 0x07;
|
|
r->coeffs[8 * i + 5] =
|
|
(a[3 * i + 1] >> 7) | ((a[3 * i + 2] & 0x03) << 1);
|
|
r->coeffs[8 * i + 6] = (a[3 * i + 2] >> 2) & 0x07;
|
|
r->coeffs[8 * i + 7] = (a[3 * i + 2] >> 5);
|
|
|
|
r->coeffs[8 * i + 0] = Q + ETA - r->coeffs[8 * i + 0];
|
|
r->coeffs[8 * i + 1] = Q + ETA - r->coeffs[8 * i + 1];
|
|
r->coeffs[8 * i + 2] = Q + ETA - r->coeffs[8 * i + 2];
|
|
r->coeffs[8 * i + 3] = Q + ETA - r->coeffs[8 * i + 3];
|
|
r->coeffs[8 * i + 4] = Q + ETA - r->coeffs[8 * i + 4];
|
|
r->coeffs[8 * i + 5] = Q + ETA - r->coeffs[8 * i + 5];
|
|
r->coeffs[8 * i + 6] = Q + ETA - r->coeffs[8 * i + 6];
|
|
r->coeffs[8 * i + 7] = Q + ETA - r->coeffs[8 * i + 7];
|
|
}
|
|
#else
|
|
for (i = 0; i < N / 2; ++i) {
|
|
r->coeffs[2 * i + 0] = a[i] & 0x0F;
|
|
r->coeffs[2 * i + 1] = a[i] >> 4;
|
|
r->coeffs[2 * i + 0] = Q + ETA - r->coeffs[2 * i + 0];
|
|
r->coeffs[2 * i + 1] = Q + ETA - r->coeffs[2 * i + 1];
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*************************************************
|
|
* Name: polyt1_pack
|
|
*
|
|
* Description: Bit-pack polynomial t1 with coefficients fitting in 9 bits.
|
|
* Input coefficients are assumed to be standard representatives.
|
|
*
|
|
* Arguments: - unsigned char *r: pointer to output byte array with at least
|
|
* POLT1_SIZE_PACKED bytes
|
|
* - const poly *a: pointer to input polynomial
|
|
**************************************************/
|
|
void PQCLEAN_DILITHIUMIII_CLEAN_polyt1_pack(unsigned char *r, const poly *a) {
|
|
#if D != 14
|
|
#error "polyt1_pack() assumes D == 14"
|
|
#endif
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < N / 8; ++i) {
|
|
r[9 * i + 0] = a->coeffs[8 * i + 0] & 0xFF;
|
|
r[9 * i + 1] = (a->coeffs[8 * i + 0] >> 8) | ((a->coeffs[8 * i + 1] & 0x7F) << 1);
|
|
r[9 * i + 2] = (a->coeffs[8 * i + 1] >> 7) | ((a->coeffs[8 * i + 2] & 0x3F) << 2);
|
|
r[9 * i + 3] = (a->coeffs[8 * i + 2] >> 6) | ((a->coeffs[8 * i + 3] & 0x1F) << 3);
|
|
r[9 * i + 4] = (a->coeffs[8 * i + 3] >> 5) | ((a->coeffs[8 * i + 4] & 0x0F) << 4);
|
|
r[9 * i + 5] = (a->coeffs[8 * i + 4] >> 4) | ((a->coeffs[8 * i + 5] & 0x07) << 5);
|
|
r[9 * i + 6] = (a->coeffs[8 * i + 5] >> 3) | ((a->coeffs[8 * i + 6] & 0x03) << 6);
|
|
r[9 * i + 7] = (a->coeffs[8 * i + 6] >> 2) | ((a->coeffs[8 * i + 7] & 0x01) << 7);
|
|
r[9 * i + 8] = a->coeffs[8 * i + 7] >> 1;
|
|
}
|
|
}
|
|
|
|
/*************************************************
|
|
* Name: polyt1_unpack
|
|
*
|
|
* Description: Unpack polynomial t1 with 9-bit coefficients.
|
|
* Output coefficients are standard representatives.
|
|
*
|
|
* Arguments: - poly *r: pointer to output polynomial
|
|
* - const unsigned char *a: byte array with bit-packed polynomial
|
|
**************************************************/
|
|
void PQCLEAN_DILITHIUMIII_CLEAN_polyt1_unpack(poly *r, const unsigned char *a) {
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < N / 8; ++i) {
|
|
r->coeffs[8 * i + 0] = a[9 * i + 0] | ((uint32_t)(a[9 * i + 1] & 0x01) << 8);
|
|
r->coeffs[8 * i + 1] = (a[9 * i + 1] >> 1) | ((uint32_t)(a[9 * i + 2] & 0x03) << 7);
|
|
r->coeffs[8 * i + 2] = (a[9 * i + 2] >> 2) | ((uint32_t)(a[9 * i + 3] & 0x07) << 6);
|
|
r->coeffs[8 * i + 3] = (a[9 * i + 3] >> 3) | ((uint32_t)(a[9 * i + 4] & 0x0F) << 5);
|
|
r->coeffs[8 * i + 4] = (a[9 * i + 4] >> 4) | ((uint32_t)(a[9 * i + 5] & 0x1F) << 4);
|
|
r->coeffs[8 * i + 5] = (a[9 * i + 5] >> 5) | ((uint32_t)(a[9 * i + 6] & 0x3F) << 3);
|
|
r->coeffs[8 * i + 6] = (a[9 * i + 6] >> 6) | ((uint32_t)(a[9 * i + 7] & 0x7F) << 2);
|
|
r->coeffs[8 * i + 7] = (a[9 * i + 7] >> 7) | ((uint32_t)(a[9 * i + 8] & 0xFF) << 1);
|
|
}
|
|
}
|
|
|
|
/*************************************************
|
|
* Name: polyt0_pack
|
|
*
|
|
* Description: Bit-pack polynomial t0 with coefficients in ]-2^{D-1}, 2^{D-1}].
|
|
* Input coefficients are assumed to lie in ]Q-2^{D-1}, Q+2^{D-1}].
|
|
*
|
|
* Arguments: - unsigned char *r: pointer to output byte array with at least
|
|
* POLT0_SIZE_PACKED bytes
|
|
* - const poly *a: pointer to input polynomial
|
|
**************************************************/
|
|
void PQCLEAN_DILITHIUMIII_CLEAN_polyt0_pack(unsigned char *r, const poly *a) {
|
|
unsigned int i;
|
|
uint32_t t[4];
|
|
|
|
for (i = 0; i < N / 4; ++i) {
|
|
t[0] = Q + (1 << (D - 1)) - a->coeffs[4 * i + 0];
|
|
t[1] = Q + (1 << (D - 1)) - a->coeffs[4 * i + 1];
|
|
t[2] = Q + (1 << (D - 1)) - a->coeffs[4 * i + 2];
|
|
t[3] = Q + (1 << (D - 1)) - a->coeffs[4 * i + 3];
|
|
|
|
r[7 * i + 0] = t[0];
|
|
r[7 * i + 1] = t[0] >> 8;
|
|
r[7 * i + 1] |= t[1] << 6;
|
|
r[7 * i + 2] = t[1] >> 2;
|
|
r[7 * i + 3] = t[1] >> 10;
|
|
r[7 * i + 3] |= t[2] << 4;
|
|
r[7 * i + 4] = t[2] >> 4;
|
|
r[7 * i + 5] = t[2] >> 12;
|
|
r[7 * i + 5] |= t[3] << 2;
|
|
r[7 * i + 6] = t[3] >> 6;
|
|
}
|
|
}
|
|
|
|
/*************************************************
|
|
* Name: polyt0_unpack
|
|
*
|
|
* Description: Unpack polynomial t0 with coefficients in ]-2^{D-1}, 2^{D-1}].
|
|
* Output coefficients lie in ]Q-2^{D-1},Q+2^{D-1}].
|
|
*
|
|
* Arguments: - poly *r: pointer to output polynomial
|
|
* - const unsigned char *a: byte array with bit-packed polynomial
|
|
**************************************************/
|
|
void PQCLEAN_DILITHIUMIII_CLEAN_polyt0_unpack(poly *r, const unsigned char *a) {
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < N / 4; ++i) {
|
|
r->coeffs[4 * i + 0] = a[7 * i + 0];
|
|
r->coeffs[4 * i + 0] |= (uint32_t)(a[7 * i + 1] & 0x3F) << 8;
|
|
|
|
r->coeffs[4 * i + 1] = a[7 * i + 1] >> 6;
|
|
r->coeffs[4 * i + 1] |= (uint32_t)a[7 * i + 2] << 2;
|
|
r->coeffs[4 * i + 1] |= (uint32_t)(a[7 * i + 3] & 0x0F) << 10;
|
|
|
|
r->coeffs[4 * i + 2] = a[7 * i + 3] >> 4;
|
|
r->coeffs[4 * i + 2] |= (uint32_t)a[7 * i + 4] << 4;
|
|
r->coeffs[4 * i + 2] |= (uint32_t)(a[7 * i + 5] & 0x03) << 12;
|
|
|
|
r->coeffs[4 * i + 3] = a[7 * i + 5] >> 2;
|
|
r->coeffs[4 * i + 3] |= (uint32_t)a[7 * i + 6] << 6;
|
|
|
|
r->coeffs[4 * i + 0] = Q + (1 << (D - 1)) - r->coeffs[4 * i + 0];
|
|
r->coeffs[4 * i + 1] = Q + (1 << (D - 1)) - r->coeffs[4 * i + 1];
|
|
r->coeffs[4 * i + 2] = Q + (1 << (D - 1)) - r->coeffs[4 * i + 2];
|
|
r->coeffs[4 * i + 3] = Q + (1 << (D - 1)) - r->coeffs[4 * i + 3];
|
|
}
|
|
}
|
|
|
|
/*************************************************
|
|
* Name: polyz_pack
|
|
*
|
|
* Description: Bit-pack polynomial z with coefficients
|
|
* in [-(GAMMA1 - 1), GAMMA1 - 1].
|
|
* Input coefficients are assumed to be standard representatives.
|
|
*
|
|
* Arguments: - unsigned char *r: pointer to output byte array with at least
|
|
* POLZ_SIZE_PACKED bytes
|
|
* - const poly *a: pointer to input polynomial
|
|
**************************************************/
|
|
void PQCLEAN_DILITHIUMIII_CLEAN_polyz_pack(unsigned char *r, const poly *a) {
|
|
#if GAMMA1 > (1 << 19)
|
|
#error "polyz_pack() assumes GAMMA1 <= 2^{19}"
|
|
#endif
|
|
unsigned int i;
|
|
uint32_t t[2];
|
|
|
|
for (i = 0; i < N / 2; ++i) {
|
|
/* Map to {0,...,2*GAMMA1 - 2} */
|
|
t[0] = GAMMA1 - 1 - a->coeffs[2 * i + 0];
|
|
t[0] += ((int32_t)t[0] >> 31) & Q;
|
|
t[1] = GAMMA1 - 1 - a->coeffs[2 * i + 1];
|
|
t[1] += ((int32_t)t[1] >> 31) & Q;
|
|
|
|
r[5 * i + 0] = t[0];
|
|
r[5 * i + 1] = t[0] >> 8;
|
|
r[5 * i + 2] = t[0] >> 16;
|
|
r[5 * i + 2] |= t[1] << 4;
|
|
r[5 * i + 3] = t[1] >> 4;
|
|
r[5 * i + 4] = t[1] >> 12;
|
|
}
|
|
}
|
|
|
|
/*************************************************
|
|
* Name: polyz_unpack
|
|
*
|
|
* Description: Unpack polynomial z with coefficients
|
|
* in [-(GAMMA1 - 1), GAMMA1 - 1].
|
|
* Output coefficients are standard representatives.
|
|
*
|
|
* Arguments: - poly *r: pointer to output polynomial
|
|
* - const unsigned char *a: byte array with bit-packed polynomial
|
|
**************************************************/
|
|
void PQCLEAN_DILITHIUMIII_CLEAN_polyz_unpack(poly *r, const unsigned char *a) {
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < N / 2; ++i) {
|
|
r->coeffs[2 * i + 0] = a[5 * i + 0];
|
|
r->coeffs[2 * i + 0] |= (uint32_t)a[5 * i + 1] << 8;
|
|
r->coeffs[2 * i + 0] |= (uint32_t)(a[5 * i + 2] & 0x0F) << 16;
|
|
|
|
r->coeffs[2 * i + 1] = a[5 * i + 2] >> 4;
|
|
r->coeffs[2 * i + 1] |= (uint32_t)a[5 * i + 3] << 4;
|
|
r->coeffs[2 * i + 1] |= (uint32_t)a[5 * i + 4] << 12;
|
|
|
|
r->coeffs[2 * i + 0] = GAMMA1 - 1 - r->coeffs[2 * i + 0];
|
|
r->coeffs[2 * i + 0] += ((int32_t)r->coeffs[2 * i + 0] >> 31) & Q;
|
|
r->coeffs[2 * i + 1] = GAMMA1 - 1 - r->coeffs[2 * i + 1];
|
|
r->coeffs[2 * i + 1] += ((int32_t)r->coeffs[2 * i + 1] >> 31) & Q;
|
|
}
|
|
}
|
|
|
|
/*************************************************
|
|
* Name: polyw1_pack
|
|
*
|
|
* Description: Bit-pack polynomial w1 with coefficients in [0, 15].
|
|
* Input coefficients are assumed to be standard representatives.
|
|
*
|
|
* Arguments: - unsigned char *r: pointer to output byte array with at least
|
|
* POLW1_SIZE_PACKED bytes
|
|
* - const poly *a: pointer to input polynomial
|
|
**************************************************/
|
|
void PQCLEAN_DILITHIUMIII_CLEAN_polyw1_pack(unsigned char *r, const poly *a) {
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < N / 2; ++i) {
|
|
r[i] = a->coeffs[2 * i + 0] | (a->coeffs[2 * i + 1] << 4);
|
|
}
|
|
}
|