Files
data-lite-c/Sources/DataLiteC/libtomcrypt/pk/ecc/ecc_verify_hash_eth27.c

54 lines
1.7 KiB
C

/* LibTomCrypt, modular cryptographic library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
#include "tomcrypt_private.h"
#ifdef LTC_MECC
/**
@file ecc_verify_hash.c
ECC Crypto, Tom St Denis
*/
/**
Verify an ECC signature (Ethereum format with recovery_id+27)
@param sig The signature to verify
@param siglen The length of the signature (octets)
@param hash The hash (message digest) that was signed
@param hashlen The length of the hash (octets)
@param stat [out] Result of signature, 1==valid, 0==invalid
@param key The corresponding public ECC key
@return CRYPT_OK if successful (even if the signature is not valid)
*/
int ecc_verify_hash_eth27(const unsigned char *sig, unsigned long siglen,
const unsigned char *hash, unsigned long hashlen,
int *stat, const ecc_key *key)
{
void *r, *s;
int err;
LTC_ARGCHK(sig != NULL);
LTC_ARGCHK(key != NULL);
/* Only valid for secp256k1 - OID 1.3.132.0.10 */
if (pk_oid_cmp_with_ulong("1.3.132.0.10", key->dp.oid, key->dp.oidlen) != CRYPT_OK) {
return CRYPT_ERROR;
}
/* Only secp256k1 curves uses this format, so must be 65 bytes long */
if (siglen != 65) {
return CRYPT_INVALID_PACKET;
}
if ((err = ltc_mp_init_multi(&r, &s, LTC_NULL)) != CRYPT_OK) return err;
if ((err = ltc_mp_read_unsigned_bin(r, (unsigned char *)sig, 32)) != CRYPT_OK) goto error;
if ((err = ltc_mp_read_unsigned_bin(s, (unsigned char *)sig + 32, 32)) != CRYPT_OK) goto error;
err = ecc_verify_hash_internal(r, s, hash, hashlen, stat, key);
error:
ltc_mp_deinit_multi(r, s, LTC_NULL);
return err;
}
#endif