diff options
author | Andy Polyakov <appro@openssl.org> | 2017-12-23 15:15:30 +0100 |
---|---|---|
committer | Andy Polyakov <appro@openssl.org> | 2017-12-27 12:27:01 +0100 |
commit | 8af7e94d7b720224547efa7e3364857f7f666dd4 (patch) | |
tree | ee39d26916d2daec875bcc79f8b84d269efa3bc0 /crypto | |
parent | b78eb0b697f3ba680c5c6e8576ece82ee680068b (diff) |
ec/ecp_nistp*.c: sanitize for undefined/implmentation-specific behaviour.
Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/4974)
Diffstat (limited to 'crypto')
-rw-r--r-- | crypto/ec/ecp_nistp224.c | 1 | ||||
-rw-r--r-- | crypto/ec/ecp_nistp256.c | 29 | ||||
-rw-r--r-- | crypto/ec/ecp_nistp521.c | 9 |
3 files changed, 19 insertions, 20 deletions
diff --git a/crypto/ec/ecp_nistp224.c b/crypto/ec/ecp_nistp224.c index c74c302cf3..9a9b8a445e 100644 --- a/crypto/ec/ecp_nistp224.c +++ b/crypto/ec/ecp_nistp224.c @@ -50,7 +50,6 @@ typedef __uint128_t uint128_t; /* nonstandard; implemented by gcc on 64-bit typedef uint8_t u8; typedef uint64_t u64; -typedef int64_t s64; /******************************************************************************/ /*- diff --git a/crypto/ec/ecp_nistp256.c b/crypto/ec/ecp_nistp256.c index bb275db30d..d8f7e8aa3f 100644 --- a/crypto/ec/ecp_nistp256.c +++ b/crypto/ec/ecp_nistp256.c @@ -53,7 +53,6 @@ typedef __int128_t int128_t; typedef uint8_t u8; typedef uint32_t u32; typedef uint64_t u64; -typedef int64_t s64; /* * The underlying field. P256 operates over GF(2^256-2^224+2^192+2^96-1). We @@ -394,7 +393,7 @@ static void felem_shrink(smallfelem out, const felem in) { felem tmp; u64 a, b, mask; - s64 high, low; + u64 high, low; static const u64 kPrime3Test = 0x7fffffff00000001ul; /* 2^63 - 2^32 + 1 */ /* Carry 2->3 */ @@ -435,29 +434,31 @@ static void felem_shrink(smallfelem out, const felem in) * In order to make space in tmp[3] for the carry from 2 -> 3, we * conditionally subtract kPrime if tmp[3] is large enough. */ - high = tmp[3] >> 64; + high = (u64)(tmp[3] >> 64); /* As tmp[3] < 2^65, high is either 1 or 0 */ - high <<= 63; - high >>= 63; + high = 0 - high; /*- * high is: * all ones if the high word of tmp[3] is 1 - * all zeros if the high word of tmp[3] if 0 */ - low = tmp[3]; - mask = low >> 63; + * all zeros if the high word of tmp[3] if 0 + */ + low = (u64)tmp[3]; + mask = 0 - (low >> 63); /*- * mask is: * all ones if the MSB of low is 1 - * all zeros if the MSB of low if 0 */ + * all zeros if the MSB of low if 0 + */ low &= bottom63bits; low -= kPrime3Test; /* if low was greater than kPrime3Test then the MSB is zero */ low = ~low; - low >>= 63; + low = 0 - (low >> 63); /*- * low is: * all ones if low was > kPrime3Test - * all zeros if low was <= kPrime3Test */ + * all zeros if low was <= kPrime3Test + */ mask = (mask & low) | high; tmp[0] -= mask & kPrime[0]; tmp[1] -= mask & kPrime[1]; @@ -891,7 +892,7 @@ static void felem_contract(smallfelem out, const felem in) equal &= equal << 4; equal &= equal << 2; equal &= equal << 1; - equal = ((s64) equal) >> 63; + equal = 0 - (equal >> 63); all_equal_so_far &= equal; } @@ -958,7 +959,7 @@ static limb smallfelem_is_zero(const smallfelem small) is_zero &= is_zero << 4; is_zero &= is_zero << 2; is_zero &= is_zero << 1; - is_zero = ((s64) is_zero) >> 63; + is_zero = 0 - (is_zero >> 63); is_p = (small[0] ^ kPrime[0]) | (small[1] ^ kPrime[1]) | @@ -970,7 +971,7 @@ static limb smallfelem_is_zero(const smallfelem small) is_p &= is_p << 4; is_p &= is_p << 2; is_p &= is_p << 1; - is_p = ((s64) is_p) >> 63; + is_p = 0 - (is_p >> 63); is_zero |= is_p; diff --git a/crypto/ec/ecp_nistp521.c b/crypto/ec/ecp_nistp521.c index 9d264f63d4..dcb5415c69 100644 --- a/crypto/ec/ecp_nistp521.c +++ b/crypto/ec/ecp_nistp521.c @@ -50,7 +50,6 @@ typedef __uint128_t uint128_t; /* nonstandard; implemented by gcc on 64-bit typedef uint8_t u8; typedef uint64_t u64; -typedef int64_t s64; /* * The underlying field. P521 operates over GF(2^521-1). We can serialise an @@ -867,7 +866,7 @@ static limb felem_is_zero(const felem in) * We know that ftmp[i] < 2^63, therefore the only way that the top bit * can be set is if is_zero was 0 before the decrement. */ - is_zero = ((s64) is_zero) >> 63; + is_zero = 0 - (is_zero >> 63); is_p = ftmp[0] ^ kPrime[0]; is_p |= ftmp[1] ^ kPrime[1]; @@ -880,7 +879,7 @@ static limb felem_is_zero(const felem in) is_p |= ftmp[8] ^ kPrime[8]; is_p--; - is_p = ((s64) is_p) >> 63; + is_p = 0 - (is_p >> 63); is_zero |= is_p; return is_zero; @@ -951,7 +950,7 @@ static void felem_contract(felem out, const felem in) is_p &= is_p << 4; is_p &= is_p << 2; is_p &= is_p << 1; - is_p = ((s64) is_p) >> 63; + is_p = 0 - (is_p >> 63); is_p = ~is_p; /* is_p is 0 iff |out| == 2^521-1 and all ones otherwise */ @@ -977,7 +976,7 @@ static void felem_contract(felem out, const felem in) is_greater |= is_greater << 4; is_greater |= is_greater << 2; is_greater |= is_greater << 1; - is_greater = ((s64) is_greater) >> 63; + is_greater = 0 - (is_greater >> 63); out[0] -= kPrime[0] & is_greater; out[1] -= kPrime[1] & is_greater; |