diff options
| author | Jason A. Donenfeld <Jason@zx2c4.com> | 2017-03-19 17:14:38 +0100 |
|---|---|---|
| committer | Jason A. Donenfeld <Jason@zx2c4.com> | 2017-03-19 23:11:31 +0100 |
| commit | 05acbf5bbbf5f6a377dc001ac945ea8e214c87b8 (patch) | |
| tree | 1fd4ab4957fa75bbfbd220365874de15e2af9db1 /src/crypto/curve25519.c | |
| parent | 2fc244a152cef280b88ca1c33a1258aec3bbdc4b (diff) | |
curve25519: add AVX implementation
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Diffstat (limited to 'src/crypto/curve25519.c')
| -rw-r--r-- | src/crypto/curve25519.c | 79 |
1 files changed, 56 insertions, 23 deletions
diff --git a/src/crypto/curve25519.c b/src/crypto/curve25519.c index 6a1bcd0..539c31a 100644 --- a/src/crypto/curve25519.c +++ b/src/crypto/curve25519.c @@ -10,6 +10,22 @@ #include <linux/random.h> #include <crypto/algapi.h> +#ifdef CONFIG_X86_64 +#include <asm/cpufeature.h> +#include <asm/processor.h> +#include <asm/fpu/api.h> +#include <asm/simd.h> +static bool curve25519_use_avx __read_mostly = false; +void curve25519_fpu_init(void) +{ + curve25519_use_avx = boot_cpu_has(X86_FEATURE_AVX); +} +asmlinkage void curve25519_sandy2x(u8 *q, const u8 *n, const u8 *p); +asmlinkage void curve25519_sandy2x_base(u8 *q, const u8 *n); +#else +void curve25519_fpu_init(void) { } +#endif + static __always_inline void normalize_secret(u8 secret[CURVE25519_POINT_SIZE]) { secret[0] &= 248; @@ -395,25 +411,42 @@ static void crecip(felem out, const felem z) void curve25519(u8 mypublic[CURVE25519_POINT_SIZE], const u8 secret[CURVE25519_POINT_SIZE], const u8 basepoint[CURVE25519_POINT_SIZE]) { - limb bp[5], x[5], z[5], zmone[5]; - u8 e[32]; - - memcpy(e, secret, 32); - normalize_secret(e); - - fexpand(bp, basepoint); - cmult(x, z, e, bp); - crecip(zmone, z); - fmul(z, x, zmone); - fcontract(mypublic, z); - - memzero_explicit(e, sizeof(e)); - memzero_explicit(bp, sizeof(bp)); - memzero_explicit(x, sizeof(x)); - memzero_explicit(z, sizeof(z)); - memzero_explicit(zmone, sizeof(zmone)); + if (curve25519_use_avx && irq_fpu_usable()) { + kernel_fpu_begin(); + curve25519_sandy2x(mypublic, secret, basepoint); + kernel_fpu_end(); + } else { + limb bp[5], x[5], z[5], zmone[5]; + u8 e[32]; + + memcpy(e, secret, 32); + normalize_secret(e); + + fexpand(bp, basepoint); + cmult(x, z, e, bp); + crecip(zmone, z); + fmul(z, x, zmone); + fcontract(mypublic, z); + + memzero_explicit(e, sizeof(e)); + memzero_explicit(bp, sizeof(bp)); + memzero_explicit(x, sizeof(x)); + memzero_explicit(z, sizeof(z)); + memzero_explicit(zmone, sizeof(zmone)); + } } +void curve25519_generate_public(u8 pub[CURVE25519_POINT_SIZE], const u8 secret[CURVE25519_POINT_SIZE]) +{ + if (curve25519_use_avx && irq_fpu_usable()) { + kernel_fpu_begin(); + curve25519_sandy2x_base(pub, secret); + kernel_fpu_end(); + } else { + static const u8 basepoint[CURVE25519_POINT_SIZE] = { 9 }; + curve25519(pub, secret, basepoint); + } +} #else typedef s64 limb; @@ -1223,6 +1256,12 @@ void curve25519(u8 mypublic[CURVE25519_POINT_SIZE], const u8 secret[CURVE25519_P memzero_explicit(z, sizeof(z)); memzero_explicit(zmone, sizeof(zmone)); } + +void curve25519_generate_public(u8 pub[CURVE25519_POINT_SIZE], const u8 secret[CURVE25519_POINT_SIZE]) +{ + static const u8 basepoint[CURVE25519_POINT_SIZE] = { 9 }; + curve25519(pub, secret, basepoint); +} #endif void curve25519_generate_secret(u8 secret[CURVE25519_POINT_SIZE]) @@ -1231,10 +1270,4 @@ void curve25519_generate_secret(u8 secret[CURVE25519_POINT_SIZE]) normalize_secret(secret); } -void curve25519_generate_public(u8 pub[CURVE25519_POINT_SIZE], const u8 secret[CURVE25519_POINT_SIZE]) -{ - static const u8 basepoint[CURVE25519_POINT_SIZE] = { 9 }; - curve25519(pub, secret, basepoint); -} - #include "../selftest/curve25519.h" |