diff options
Diffstat (limited to 'src/crypto/mac/ghash/pclmulqdq/ghash_pclmulqdq_impl.c')
| -rw-r--r-- | src/crypto/mac/ghash/pclmulqdq/ghash_pclmulqdq_impl.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/src/crypto/mac/ghash/pclmulqdq/ghash_pclmulqdq_impl.c b/src/crypto/mac/ghash/pclmulqdq/ghash_pclmulqdq_impl.c index 9dc0a32..49c036a 100644 --- a/src/crypto/mac/ghash/pclmulqdq/ghash_pclmulqdq_impl.c +++ b/src/crypto/mac/ghash/pclmulqdq/ghash_pclmulqdq_impl.c @@ -23,6 +23,12 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ +/** + \file + + PCLMULQDQ-based GHASH implementation for newer x86 systems: implementation +*/ + #include "ghash_pclmulqdq.h" #include <wmmintrin.h> @@ -30,16 +36,19 @@ #include <tmmintrin.h> +/** An union allowing easy access to a block as a SIMD vector and a fastd_block128_t */ typedef union vecblock { - __m128i v; - fastd_block128_t b; + __m128i v; /**< __m128i access */ + fastd_block128_t b; /**< fastd_block128_t access */ } vecblock_t; +/** The MAC state used by this GHASH implementation */ struct fastd_mac_state { - vecblock_t H; + vecblock_t H; /**< The hash key used by GHASH */ }; +/** Left shift on a 128bit integer */ static inline __m128i shl(__m128i v, int a) { __m128i tmpl = _mm_slli_epi64(v, a); __m128i tmpr = _mm_srli_epi64(v, 64-a); @@ -48,6 +57,7 @@ static inline __m128i shl(__m128i v, int a) { return _mm_xor_si128(tmpl, tmpr); } +/** Right shift on a 128bit integer */ static inline __m128i shr(__m128i v, int a) { __m128i tmpr = _mm_srli_epi64(v, a); __m128i tmpl = _mm_slli_epi64(v, 64-a); @@ -56,13 +66,16 @@ static inline __m128i shr(__m128i v, int a) { return _mm_xor_si128(tmpr, tmpl); } +/** _mm_shuffle_epi8 parameter to reverse the bytes of a __m128i */ static const __v16qi BYTESWAP_SHUFFLE = {15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0}; +/** Reverses the order of the bytes of a __m128i */ static inline __m128i byteswap(__m128i v) { return _mm_shuffle_epi8(v, (__m128i)BYTESWAP_SHUFFLE); } +/** Initializes the state used by this GHASH implementation */ fastd_mac_state_t* fastd_ghash_pclmulqdq_init(const uint8_t *key) { fastd_mac_state_t *state; if (posix_memalign((void**)&state, 16, sizeof(fastd_mac_state_t))) @@ -74,6 +87,7 @@ fastd_mac_state_t* fastd_ghash_pclmulqdq_init(const uint8_t *key) { return state; } +/** Frees the state used by this GHASH implementation */ void fastd_ghash_pclmulqdq_free(fastd_mac_state_t *state) { if (state) { secure_memzero(state, sizeof(*state)); @@ -81,6 +95,7 @@ void fastd_ghash_pclmulqdq_free(fastd_mac_state_t *state) { } } +/** Performs a carryless multiplication of two 128bit integers modulo \f$ x^{128} + x^7 + x^2 + x + 1 \f$ */ static __m128i gmul(__m128i v, __m128i h) { /* multiply */ __m128i z0, z1, z2, tmp; @@ -134,6 +149,7 @@ static __m128i gmul(__m128i v, __m128i h) { } +/** Calculates the GHASH of the supplied input blocks */ bool fastd_ghash_pclmulqdq_hash(const fastd_mac_state_t *state, fastd_block128_t *out, const fastd_block128_t *in, size_t n_blocks) { vecblock_t v = {.v = _mm_setzero_si128()}; |