diff --git a/crypto/ecdsa/ecs_ossl.c b/crypto/ecdsa/ecs_ossl.c index f8b5d4ed6a2e53f4116dc1621f5c98f0bcff1a7a..3ead1af94e7351c5e4bf76aefe146e61b1e636a5 100644 --- a/crypto/ecdsa/ecs_ossl.c +++ b/crypto/ecdsa/ecs_ossl.c @@ -384,6 +384,21 @@ static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len, ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); goto err; } + if (8 * dgst_len > BN_num_bits(order)) + { + /* XXX + * + * Should provide for optional hash truncation: + * Keep the BN_num_bits(order) leftmost bits of dgst + * (see March 2006 FIPS 186-3 draft, which has a few + * confusing errors in this part though) + */ + + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, + ECDSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE); + ret = 0; + goto err; + } if (BN_is_zero(sig->r) || BN_is_negative(sig->r) || BN_ucmp(sig->r, order) >= 0 || BN_is_zero(sig->s) ||