42 #include <mbedtls/ctr_drbg.h> 43 #include <mbedtls/entropy.h> 47 "FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD1" \ 48 "29024E088A67CC74020BBEA63B139B22514A08798E3404DD" \ 49 "EF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245" \ 50 "E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7ED" \ 51 "EE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381" \ 55 "7FFFFFFFFFFFFFFFE487ED5110B4611A62633145C06E0E68" \ 56 "948127044533E63A0105DF531D89CD9128A5043CC71A026E" \ 57 "F7CA8CD9E69D218D98158536F92F8A1BA7F09AB6B6A8E122" \ 58 "F242DABB312F3F637A262174D31BF6B585FFAE5B7A035BF6" \ 59 "F71C35FDAD44CFD2D74F9208BE258FF324943328F67329C0" \ 65 bn = av_malloc(sizeof(*bn)); \ 74 #define bn_set_word(bn, w) mpz_set_ui(bn, w) 75 #define bn_cmp(a, b) mpz_cmp(a, b) 76 #define bn_copy(to, from) mpz_set(to, from) 77 #define bn_sub_word(bn, w) mpz_sub_ui(bn, bn, w) 78 #define bn_cmp_1(bn) mpz_cmp_ui(bn, 1) 79 #define bn_num_bytes(bn) (mpz_sizeinbase(bn, 2) + 7) / 8 80 #define bn_bn2bin(bn, buf, len) \ 82 memset(buf, 0, len); \ 83 if (bn_num_bytes(bn) <= len) \ 84 mpz_export(buf, NULL, 1, 1, 0, 0, bn); \ 86 #define bn_bin2bn(bn, buf, len) \ 90 mpz_import(bn, len, 1, 1, 0, 0, buf); \ 92 #define bn_hex2bn(bn, buf, ret) \ 96 ret = (mpz_set_str(bn, buf, 16) == 0); \ 100 #define bn_random(bn, num_bits) \ 102 int bits = num_bits; \ 104 for (bits = num_bits; bits > 0; bits -= 32) { \ 105 mpz_mul_2exp(bn, bn, 32); \ 106 mpz_add_ui(bn, bn, av_get_random_seed()); \ 108 mpz_fdiv_r_2exp(bn, bn, num_bits); \ 110 static int bn_modexp(FFBigNum bn, FFBigNum y, FFBigNum q, FFBigNum
p)
112 mpz_powm(bn, y, q, p);
118 if (!gcry_control(GCRYCTL_INITIALIZATION_FINISHED_P)) { \ 119 if (!gcry_check_version("1.5.4")) \ 120 return AVERROR(EINVAL); \ 121 gcry_control(GCRYCTL_DISABLE_SECMEM, 0); \ 122 gcry_control(GCRYCTL_INITIALIZATION_FINISHED, 0); \ 124 bn = gcry_mpi_new(1); \ 126 #define bn_free(bn) gcry_mpi_release(bn) 127 #define bn_set_word(bn, w) gcry_mpi_set_ui(bn, w) 128 #define bn_cmp(a, b) gcry_mpi_cmp(a, b) 129 #define bn_copy(to, from) gcry_mpi_set(to, from) 130 #define bn_sub_word(bn, w) gcry_mpi_sub_ui(bn, bn, w) 131 #define bn_cmp_1(bn) gcry_mpi_cmp_ui(bn, 1) 132 #define bn_num_bytes(bn) (gcry_mpi_get_nbits(bn) + 7) / 8 133 #define bn_bn2bin(bn, buf, len) gcry_mpi_print(GCRYMPI_FMT_USG, buf, len, NULL, bn) 134 #define bn_bin2bn(bn, buf, len) gcry_mpi_scan(&bn, GCRYMPI_FMT_USG, buf, len, NULL) 135 #define bn_hex2bn(bn, buf, ret) ret = (gcry_mpi_scan(&bn, GCRYMPI_FMT_HEX, buf, 0, 0) == 0) 136 #define bn_random(bn, num_bits) gcry_mpi_randomize(bn, num_bits, GCRY_WEAK_RANDOM) 137 static int bn_modexp(FFBigNum bn, FFBigNum y, FFBigNum q, FFBigNum
p)
139 gcry_mpi_powm(bn, y, q, p);
143 #define bn_new(bn) bn = BN_new() 144 #define bn_free(bn) BN_free(bn) 145 #define bn_set_word(bn, w) BN_set_word(bn, w) 146 #define bn_cmp(a, b) BN_cmp(a, b) 147 #define bn_copy(to, from) BN_copy(to, from) 148 #define bn_sub_word(bn, w) BN_sub_word(bn, w) 149 #define bn_cmp_1(bn) BN_cmp(bn, BN_value_one()) 150 #define bn_num_bytes(bn) BN_num_bytes(bn) 151 #define bn_bn2bin(bn, buf, len) BN_bn2bin(bn, buf) 152 #define bn_bin2bn(bn, buf, len) bn = BN_bin2bn(buf, len, 0) 153 #define bn_hex2bn(bn, buf, ret) ret = BN_hex2bn(&bn, buf) 154 #define bn_random(bn, num_bits) BN_rand(bn, num_bits, 0, 0) 155 static int bn_modexp(FFBigNum bn, FFBigNum y, FFBigNum q, FFBigNum
p)
157 BN_CTX *
ctx = BN_CTX_new();
160 if (!BN_mod_exp(bn, y, q, p, ctx)) {
170 bn = av_malloc(sizeof(*bn)); \ 172 mbedtls_mpi_init(bn); \ 174 #define bn_free(bn) \ 176 mbedtls_mpi_free(bn); \ 179 #define bn_set_word(bn, w) mbedtls_mpi_lset(bn, w) 180 #define bn_cmp(a, b) mbedtls_mpi_cmp_mpi(a, b) 181 #define bn_copy(to, from) mbedtls_mpi_copy(to, from) 182 #define bn_sub_word(bn, w) mbedtls_mpi_sub_int(bn, bn, w) 183 #define bn_cmp_1(bn) mbedtls_mpi_cmp_int(bn, 1) 184 #define bn_num_bytes(bn) (mbedtls_mpi_bitlen(bn) + 7) / 8 185 #define bn_bn2bin(bn, buf, len) mbedtls_mpi_write_binary(bn, buf, len) 186 #define bn_bin2bn(bn, buf, len) \ 190 mbedtls_mpi_read_binary(bn, buf, len); \ 192 #define bn_hex2bn(bn, buf, ret) \ 196 ret = (mbedtls_mpi_read_string(bn, 16, buf) == 0); \ 200 #define bn_random(bn, num_bits) \ 202 mbedtls_entropy_context entropy_ctx; \ 203 mbedtls_ctr_drbg_context ctr_drbg_ctx; \ 205 mbedtls_entropy_init(&entropy_ctx); \ 206 mbedtls_ctr_drbg_init(&ctr_drbg_ctx); \ 207 mbedtls_ctr_drbg_seed(&ctr_drbg_ctx, \ 208 mbedtls_entropy_func, \ 211 mbedtls_mpi_fill_random(bn, (num_bits + 7) / 8, mbedtls_ctr_drbg_random, &ctr_drbg_ctx); \ 212 mbedtls_ctr_drbg_free(&ctr_drbg_ctx); \ 213 mbedtls_entropy_free(&entropy_ctx); \ 215 #define bn_modexp(bn, y, q, p) mbedtls_mpi_exp_mod(bn, y, q, p, 0) 219 #define MAX_BYTES 18000 221 #define dh_new() av_mallocz(sizeof(FF_DH)) 227 num_bytes = bn_num_bytes(dh->
p) - 1;
228 if (num_bytes <= 0 || num_bytes >
MAX_BYTES)
234 bn_random(dh->
priv_key, 8 * num_bytes);
249 uint32_t secret_key_len,
uint8_t *secret_key)
258 if ((ret = bn_modexp(k, pub_key_bn, dh->
priv_key, dh->
p)) < 0) {
262 bn_bn2bin(k, secret_key, secret_key_len);
266 return secret_key_len;
307 if ((ret = bn_modexp(bn, y, q, p)) < 0)
333 bn_hex2bn(dh->
p,
P1024, ret);
337 bn_set_word(dh->
g, 2);
358 bn_hex2bn(q1,
Q1024, ret);
379 len = bn_num_bytes(dh->
pub_key);
380 if (len <= 0 || len > pub_key_len)
384 memset(pub_key, 0, pub_key_len);
385 bn_bn2bin(dh->
pub_key, pub_key + pub_key_len - len, len);
391 int pub_key_len,
uint8_t *secret_key,
398 bn_bin2bn(pub_key_bn, pub_key, pub_key_len);
403 bn_hex2bn(q1,
Q1024, ret);
uint32_t p[AV_BF_ROUNDS+2]
int ff_dh_write_public_key(FF_DH *dh, uint8_t *pub_key, int pub_key_len)
Write the public key into the given buffer.
static int dh_is_valid_public_key(FFBigNum y, FFBigNum p, FFBigNum q)
Memory handling functions.
int ff_dh_compute_shared_secret_key(FF_DH *dh, const uint8_t *pub_key, int pub_key_len, uint8_t *secret_key, int secret_key_len)
Compute the shared secret key from the private FF_DH value and the other party's public value...
void ff_dh_free(FF_DH *dh)
Free a Diffie-Hellmann context.
static const uint8_t q1[256]
Macro definitions for various function/variable attributes.
int ff_dh_generate_public_key(FF_DH *dh)
Generate a public key.
static int dh_compute_key(FF_DH *dh, FFBigNum pub_key_bn, uint32_t secret_key_len, uint8_t *secret_key)
av_cold FF_DH * ff_dh_init(int key_len)
Initialize a Diffie-Hellmann context.
static FFBigNum dh_generate_key(FF_DH *dh)