hash_sha_sse2.c

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/*-
 * Copyright 2021 Tarsnap Backup Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
 
#include "php_hash.h"
#include "php_hash_sha.h"
 
#ifdef __SSE2__
# include <emmintrin.h>
 
/* Original implementation from libcperciva follows.
 *
 * Modified to use `PHP_STATIC_RESTRICT` for MSVC compatibility.
 */

static inline __m128i
mm_bswap_epi32(__m128i a)
{
 
    /* Swap bytes in each 16-bit word. */
    a = _mm_or_si128(_mm_slli_epi16(a, 8), _mm_srli_epi16(a, 8));
 
    /* Swap all 16-bit words. */
    a = _mm_shufflelo_epi16(a, _MM_SHUFFLE(2, 3, 0, 1));
    a = _mm_shufflehi_epi16(a, _MM_SHUFFLE(2, 3, 0, 1));
 
    return (a);
}
 
/* SHA256 round constants. */
static const uint32_t Krnd[64] = {
    0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
    0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
    0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
    0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
    0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
    0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
    0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
    0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
    0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
    0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
    0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
    0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
    0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
    0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
    0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
    0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
};
 
/* Elementary functions used by SHA256 */
#define Ch(x, y, z) ((x & (y ^ z)) ^ z)
#define Maj(x, y, z)    ((x & (y | z)) | (y & z))
#define ROTR(x, n)  ((x >> n) | (x << (32 - n)))
#define S0(x)       (ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22))
#define S1(x)       (ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25))
 
/* SHA256 round function */
#define RND(a, b, c, d, e, f, g, h, k)          \
    h += S1(e) + Ch(e, f, g) + k;           \
    d += h;                     \
    h += S0(a) + Maj(a, b, c)
 
/* Adjusted round function for rotating state */
#define RNDr(S, W, i, ii)           \
    RND(S[(64 - i) % 8], S[(65 - i) % 8],   \
        S[(66 - i) % 8], S[(67 - i) % 8],   \
        S[(68 - i) % 8], S[(69 - i) % 8],   \
        S[(70 - i) % 8], S[(71 - i) % 8],   \
        W[i + ii] + Krnd[i + ii])
 
/* Message schedule computation */
#define SHR32(x, n) (_mm_srli_epi32(x, n))
#define ROTR32(x, n) (_mm_or_si128(SHR32(x, n), _mm_slli_epi32(x, (32-n))))
#define s0_128(x) _mm_xor_si128(_mm_xor_si128(          \
    ROTR32(x, 7), ROTR32(x, 18)), SHR32(x, 3))
 
static inline __m128i
s1_128_high(__m128i a)
{
    __m128i b;
    __m128i c;
 
    /* ROTR, loading data as {B, B, A, A}; lanes 1 & 3 will be junk. */
    b = _mm_shuffle_epi32(a, _MM_SHUFFLE(1, 1, 0, 0));
    c = _mm_xor_si128(_mm_srli_epi64(b, 17), _mm_srli_epi64(b, 19));
 
    /* Shift and XOR with rotated data; lanes 1 & 3 will be junk. */
    c = _mm_xor_si128(c, _mm_srli_epi32(b, 10));
 
    /* Shuffle good data back and zero unwanted lanes. */
    c = _mm_shuffle_epi32(c, _MM_SHUFFLE(2, 0, 2, 0));
    c = _mm_slli_si128(c, 8);
 
    return (c);
}
 
static inline __m128i
s1_128_low(__m128i a)
{
    __m128i b;
    __m128i c;
 
    /* ROTR, loading data as {B, B, A, A}; lanes 1 & 3 will be junk. */
    b = _mm_shuffle_epi32(a, _MM_SHUFFLE(3, 3, 2, 2));
    c = _mm_xor_si128(_mm_srli_epi64(b, 17), _mm_srli_epi64(b, 19));
 
    /* Shift and XOR with rotated data; lanes 1 & 3 will be junk. */
    c = _mm_xor_si128(c, _mm_srli_epi32(b, 10));
 
    /* Shuffle good data back and zero unwanted lanes. */
    c = _mm_shuffle_epi32(c, _MM_SHUFFLE(2, 0, 2, 0));
    c = _mm_srli_si128(c, 8);
 
    return (c);
}

#define SPAN_ONE_THREE(a, b) (_mm_shuffle_epi32(_mm_castps_si128(   \
    _mm_move_ss(_mm_castsi128_ps(a), _mm_castsi128_ps(b))),     \
    _MM_SHUFFLE(0, 3, 2, 1)))

static inline __m128i
MSG4(__m128i X0, __m128i X1, __m128i X2, __m128i X3)
{
    __m128i X4;
    __m128i Xj_minus_seven, Xj_minus_fifteen;
 
    /* Set up variables which span X values. */
    Xj_minus_seven = SPAN_ONE_THREE(X2, X3);
    Xj_minus_fifteen = SPAN_ONE_THREE(X0, X1);
 
    /* Begin computing X4. */
    X4 = _mm_add_epi32(X0, Xj_minus_seven);
    X4 = _mm_add_epi32(X4, s0_128(Xj_minus_fifteen));
 
    /* First half of s1. */
    X4 = _mm_add_epi32(X4, s1_128_low(X3));
 
    /* Second half of s1; this depends on the above value of X4. */
    X4 = _mm_add_epi32(X4, s1_128_high(X4));
 
    return (X4);
}

void
SHA256_Transform_sse2(uint32_t state[PHP_STATIC_RESTRICT 8],
    const uint8_t block[PHP_STATIC_RESTRICT 64], uint32_t W[PHP_STATIC_RESTRICT 64],
    uint32_t S[PHP_STATIC_RESTRICT 8])
{
    __m128i Y[4];
    int i;
 
    /* 1. Prepare the first part of the message schedule W. */
    Y[0] = mm_bswap_epi32(_mm_loadu_si128((const __m128i *)&block[0]));
    _mm_storeu_si128((__m128i *)&W[0], Y[0]);
    Y[1] = mm_bswap_epi32(_mm_loadu_si128((const __m128i *)&block[16]));
    _mm_storeu_si128((__m128i *)&W[4], Y[1]);
    Y[2] = mm_bswap_epi32(_mm_loadu_si128((const __m128i *)&block[32]));
    _mm_storeu_si128((__m128i *)&W[8], Y[2]);
    Y[3] = mm_bswap_epi32(_mm_loadu_si128((const __m128i *)&block[48]));
    _mm_storeu_si128((__m128i *)&W[12], Y[3]);
 
    /* 2. Initialize working variables. */
    memcpy(S, state, 32);
 
    /* 3. Mix. */
    for (i = 0; i < 64; i += 16) {
        RNDr(S, W, 0, i);
        RNDr(S, W, 1, i);
        RNDr(S, W, 2, i);
        RNDr(S, W, 3, i);
        RNDr(S, W, 4, i);
        RNDr(S, W, 5, i);
        RNDr(S, W, 6, i);
        RNDr(S, W, 7, i);
        RNDr(S, W, 8, i);
        RNDr(S, W, 9, i);
        RNDr(S, W, 10, i);
        RNDr(S, W, 11, i);
        RNDr(S, W, 12, i);
        RNDr(S, W, 13, i);
        RNDr(S, W, 14, i);
        RNDr(S, W, 15, i);
 
        if (i == 48)
            break;
        Y[0] = MSG4(Y[0], Y[1], Y[2], Y[3]);
        _mm_storeu_si128((__m128i *)&W[16 + i + 0], Y[0]);
        Y[1] = MSG4(Y[1], Y[2], Y[3], Y[0]);
        _mm_storeu_si128((__m128i *)&W[16 + i + 4], Y[1]);
        Y[2] = MSG4(Y[2], Y[3], Y[0], Y[1]);
        _mm_storeu_si128((__m128i *)&W[16 + i + 8], Y[2]);
        Y[3] = MSG4(Y[3], Y[0], Y[1], Y[2]);
        _mm_storeu_si128((__m128i *)&W[16 + i + 12], Y[3]);
    }
 
    /* 4. Mix local working variables into global state. */
    for (i = 0; i < 8; i++)
        state[i] += S[i];
}
 
#endif