Add _prefix and _bip324 ellswift_xdh hash functions

This commit is contained in:
Pieter Wuille
2023-05-05 04:37:30 -04:00
parent 9695deb351
commit df633cdeba
3 changed files with 158 additions and 8 deletions

View File

@@ -498,6 +498,51 @@ int secp256k1_ellswift_decode(const secp256k1_context *ctx, secp256k1_pubkey *pu
return 1;
}
static int ellswift_xdh_hash_function_prefix(unsigned char *output, const unsigned char *x32, const unsigned char *ell_a64, const unsigned char *ell_b64, void *data) {
secp256k1_sha256 sha;
secp256k1_sha256_initialize(&sha);
secp256k1_sha256_write(&sha, data, 64);
secp256k1_sha256_write(&sha, ell_a64, 64);
secp256k1_sha256_write(&sha, ell_b64, 64);
secp256k1_sha256_write(&sha, x32, 32);
secp256k1_sha256_finalize(&sha, output);
return 1;
}
/** Set hash state to the BIP340 tagged hash midstate for "bip324_ellswift_xonly_ecdh". */
static void secp256k1_ellswift_sha256_init_bip324(secp256k1_sha256* hash) {
secp256k1_sha256_initialize(hash);
hash->s[0] = 0x8c12d730ul;
hash->s[1] = 0x827bd392ul;
hash->s[2] = 0x9e4fb2eeul;
hash->s[3] = 0x207b373eul;
hash->s[4] = 0x2292bd7aul;
hash->s[5] = 0xaa5441bcul;
hash->s[6] = 0x15c3779ful;
hash->s[7] = 0xcfb52549ul;
hash->bytes = 64;
}
static int ellswift_xdh_hash_function_bip324(unsigned char* output, const unsigned char *x32, const unsigned char *ell_a64, const unsigned char *ell_b64, void *data) {
secp256k1_sha256 sha;
(void)data;
secp256k1_ellswift_sha256_init_bip324(&sha);
secp256k1_sha256_write(&sha, ell_a64, 64);
secp256k1_sha256_write(&sha, ell_b64, 64);
secp256k1_sha256_write(&sha, x32, 32);
secp256k1_sha256_finalize(&sha, output);
return 1;
}
const secp256k1_ellswift_xdh_hash_function secp256k1_ellswift_xdh_hash_function_prefix = ellswift_xdh_hash_function_prefix;
const secp256k1_ellswift_xdh_hash_function secp256k1_ellswift_xdh_hash_function_bip324 = ellswift_xdh_hash_function_bip324;
int secp256k1_ellswift_xdh(const secp256k1_context *ctx, unsigned char *output, const unsigned char *ell_a64, const unsigned char *ell_b64, const unsigned char *seckey32, int party, secp256k1_ellswift_xdh_hash_function hashfp, void *data) {
int ret = 0;
int overflow;