#include "nistseedexpander.h" #include "parameters.h" #include "parsing.h" #include "randombytes.h" #include "vector.h" #include <stdint.h> #include <string.h> /** * @file parsing.c * @brief Functions to parse secret key, public key and ciphertext of the HQC scheme */ void PQCLEAN_HQCRMRS256_AVX2_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_HQCRMRS256_AVX2_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_HQCRMRS256_AVX2_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_HQCRMRS256_AVX2_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_HQCRMRS256_AVX2_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++; } } } /** * @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_HQCRMRS256_AVX2_hqc_secret_key_to_string(uint8_t *sk, const uint8_t *sk_seed, const uint8_t *pk) { memcpy(sk, sk_seed, SEED_BYTES); sk += SEED_BYTES; memcpy(sk, 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 uint64_t representation of vector x * @param[out] y uint64_t representation of vector y * @param[out] pk String containing the public key * @param[in] sk String containing the secret key */ void PQCLEAN_HQCRMRS256_AVX2_hqc_secret_key_from_string(uint64_t *x, uint64_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); sk += SEED_BYTES; memcpy(pk, sk, PUBLIC_KEY_BYTES); seedexpander_init(&sk_seedexpander, sk_seed, sk_seed + 32, SEEDEXPANDER_MAX_LENGTH); PQCLEAN_HQCRMRS256_AVX2_vect_set_random_fixed_weight(&sk_seedexpander, x, PARAM_OMEGA); PQCLEAN_HQCRMRS256_AVX2_vect_set_random_fixed_weight(&sk_seedexpander, y, PARAM_OMEGA); } /** * @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_HQCRMRS256_AVX2_hqc_public_key_to_string(uint8_t *pk, const uint8_t *pk_seed, const uint64_t *s) { memcpy(pk, pk_seed, SEED_BYTES); PQCLEAN_HQCRMRS256_AVX2_store8_arr(pk + SEED_BYTES, VEC_N_SIZE_BYTES, s, VEC_N_SIZE_64); } /** * @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_HQCRMRS256_AVX2_hqc_public_key_from_string(uint64_t *h, uint64_t *s, const uint8_t *pk) { AES_XOF_struct pk_seedexpander; uint8_t pk_seed[SEED_BYTES] = {0}; memcpy(pk_seed, pk, SEED_BYTES); pk += SEED_BYTES; PQCLEAN_HQCRMRS256_AVX2_load8_arr(s, VEC_N_SIZE_64, pk, VEC_N_SIZE_BYTES); seedexpander_init(&pk_seedexpander, pk_seed, pk_seed + 32, SEEDEXPANDER_MAX_LENGTH); PQCLEAN_HQCRMRS256_AVX2_vect_set_random(&pk_seedexpander, h); } /** * @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_HQCRMRS256_AVX2_hqc_ciphertext_to_string(uint8_t *ct, const uint64_t *u, const uint64_t *v, const uint8_t *d) { PQCLEAN_HQCRMRS256_AVX2_store8_arr(ct, VEC_N_SIZE_BYTES, u, VEC_N_SIZE_64); ct += VEC_N_SIZE_BYTES; PQCLEAN_HQCRMRS256_AVX2_store8_arr(ct, VEC_N1N2_SIZE_BYTES, v, VEC_N1N2_SIZE_64); ct += VEC_N1N2_SIZE_BYTES; memcpy(ct, 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_HQCRMRS256_AVX2_hqc_ciphertext_from_string(uint64_t *u, uint64_t *v, uint8_t *d, const uint8_t *ct) { PQCLEAN_HQCRMRS256_AVX2_load8_arr(u, VEC_N_SIZE_64, ct, VEC_N_SIZE_BYTES); ct += VEC_N_SIZE_BYTES; PQCLEAN_HQCRMRS256_AVX2_load8_arr(v, VEC_N1N2_SIZE_64, ct, VEC_N1N2_SIZE_BYTES); ct += VEC_N1N2_SIZE_BYTES; memcpy(d, ct, SHA512_BYTES); }