diff options
| -rw-r--r-- | crypto/ec/ec2_oct.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/crypto/ec/ec2_oct.c b/crypto/ec/ec2_oct.c index 0d04cc6923..6f2f7ca514 100644 --- a/crypto/ec/ec2_oct.c +++ b/crypto/ec/ec2_oct.c @@ -299,7 +299,7 @@ int ec_GF2m_simple_oct2point(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx) { point_conversion_form_t form; - int y_bit; + int y_bit, m; BN_CTX *new_ctx = NULL; BIGNUM *x, *y, *yxi; size_t field_len, enc_len; @@ -332,7 +332,8 @@ int ec_GF2m_simple_oct2point(const EC_GROUP *group, EC_POINT *point, return EC_POINT_set_to_infinity(group, point); } - field_len = (EC_GROUP_get_degree(group) + 7) / 8; + m = EC_GROUP_get_degree(group); + field_len = (m + 7) / 8; enc_len = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2 * field_len; @@ -357,7 +358,7 @@ int ec_GF2m_simple_oct2point(const EC_GROUP *group, EC_POINT *point, if (!BN_bin2bn(buf + 1, field_len, x)) goto err; - if (BN_ucmp(x, &group->field) >= 0) { + if (BN_num_bits(x) > m) { ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); goto err; } @@ -369,7 +370,7 @@ int ec_GF2m_simple_oct2point(const EC_GROUP *group, EC_POINT *point, } else { if (!BN_bin2bn(buf + 1 + field_len, field_len, y)) goto err; - if (BN_ucmp(y, &group->field) >= 0) { + if (BN_num_bits(y) > m) { ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); goto err; } |