diff options
Diffstat (limited to 'freebsd/crypto/openssl/crypto/ec/curve448/eddsa.c')
| -rw-r--r-- | freebsd/crypto/openssl/crypto/ec/curve448/eddsa.c | 30 |
1 files changed, 28 insertions, 2 deletions
diff --git a/freebsd/crypto/openssl/crypto/ec/curve448/eddsa.c b/freebsd/crypto/openssl/crypto/ec/curve448/eddsa.c index 56911e5d..4af630b8 100644 --- a/freebsd/crypto/openssl/crypto/ec/curve448/eddsa.c +++ b/freebsd/crypto/openssl/crypto/ec/curve448/eddsa.c @@ -248,10 +248,36 @@ c448_error_t c448_ed448_verify( uint8_t context_len) { curve448_point_t pk_point, r_point; - c448_error_t error = - curve448_point_decode_like_eddsa_and_mul_by_ratio(pk_point, pubkey); + c448_error_t error; curve448_scalar_t challenge_scalar; curve448_scalar_t response_scalar; + /* Order in little endian format */ + static const uint8_t order[] = { + 0xF3, 0x44, 0x58, 0xAB, 0x92, 0xC2, 0x78, 0x23, 0x55, 0x8F, 0xC5, 0x8D, + 0x72, 0xC2, 0x6C, 0x21, 0x90, 0x36, 0xD6, 0xAE, 0x49, 0xDB, 0x4E, 0xC4, + 0xE9, 0x23, 0xCA, 0x7C, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, + 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, + 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x3F, 0x00 + }; + int i; + + /* + * Check that s (second 57 bytes of the sig) is less than the order. Both + * s and the order are in little-endian format. This can be done in + * variable time, since if this is not the case the signature if publicly + * invalid. + */ + for (i = EDDSA_448_PUBLIC_BYTES - 1; i >= 0; i--) { + if (signature[i + EDDSA_448_PUBLIC_BYTES] > order[i]) + return C448_FAILURE; + if (signature[i + EDDSA_448_PUBLIC_BYTES] < order[i]) + break; + } + if (i < 0) + return C448_FAILURE; + + error = + curve448_point_decode_like_eddsa_and_mul_by_ratio(pk_point, pubkey); if (C448_SUCCESS != error) return error; |