crypto/sha: add Keccak1600 primitives to build SHA-3 upon.

/*

 * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <stdint.h>

#include <string.h>

#include <assert.h>

#define ROL64(a, offset) ((offset) ? (((a) << offset) | ((a) >> (64-offset))) \

                                   : a)

static void Theta(uint64_t A[5][5])

{

    uint64_t C[5], D[5];

    size_t y;

    C[0] = A[0][0] ^ A[1][0] ^ A[2][0] ^ A[3][0] ^ A[4][0];

    C[1] = A[0][1] ^ A[1][1] ^ A[2][1] ^ A[3][1] ^ A[4][1];

    C[2] = A[0][2] ^ A[1][2] ^ A[2][2] ^ A[3][2] ^ A[4][2];

    C[3] = A[0][3] ^ A[1][3] ^ A[2][3] ^ A[3][3] ^ A[4][3];

    C[4] = A[0][4] ^ A[1][4] ^ A[2][4] ^ A[3][4] ^ A[4][4];

    D[0] = ROL64(C[1], 1) ^ C[4];

    D[1] = ROL64(C[2], 1) ^ C[0];

    D[2] = ROL64(C[3], 1) ^ C[1];

    D[3] = ROL64(C[4], 1) ^ C[2];

    D[4] = ROL64(C[0], 1) ^ C[3];

    for (y = 0; y < 5; y++) {

        A[y][0] ^= D[0];

        A[y][1] ^= D[1];

        A[y][2] ^= D[2];

        A[y][3] ^= D[3];

        A[y][4] ^= D[4];

    }

}

static void Rho(uint64_t A[5][5])

{

    static const unsigned char rhotates[5][5] = {

        {  0,  1, 62, 28, 27 },

        { 36, 44,  6, 55, 20 },

        {  3, 10, 43, 25, 39 },

        { 41, 45, 15, 21,  8 },

        { 18,  2, 61, 56, 14 }

    };

    size_t y;

    for (y = 0; y < 5; y++) {

        A[y][0] = ROL64(A[y][0], rhotates[y][0]);

        A[y][1] = ROL64(A[y][1], rhotates[y][1]);

        A[y][2] = ROL64(A[y][2], rhotates[y][2]);

        A[y][3] = ROL64(A[y][3], rhotates[y][3]);

        A[y][4] = ROL64(A[y][4], rhotates[y][4]);

    }

}

static void Pi(uint64_t A[5][5])

{

    uint64_t T[5][5];

    /*

     * T = A

     * A[y][x] = T[x][(3*y+x)%5]

     */

    memcpy(T, A, sizeof(T));

    A[0][0] = T[0][0];

    A[0][1] = T[1][1];

    A[0][2] = T[2][2];

    A[0][3] = T[3][3];

    A[0][4] = T[4][4];

    A[1][0] = T[0][3];

    A[1][1] = T[1][4];

    A[1][2] = T[2][0];

    A[1][3] = T[3][1];

    A[1][4] = T[4][2];

    A[2][0] = T[0][1];

    A[2][1] = T[1][2];

    A[2][2] = T[2][3];

    A[2][3] = T[3][4];

    A[2][4] = T[4][0];

    A[3][0] = T[0][4];

    A[3][1] = T[1][0];

    A[3][2] = T[2][1];

    A[3][3] = T[3][2];

    A[3][4] = T[4][3];

    A[4][0] = T[0][2];

    A[4][1] = T[1][3];

    A[4][2] = T[2][4];

    A[4][3] = T[3][0];

    A[4][4] = T[4][1];

}

static void Chi(uint64_t A[5][5])

{

    uint64_t C[5];

    size_t y;

    for (y = 0; y < 5; y++) {

        C[0] = A[y][0] ^ (~A[y][1] & A[y][2]);

        C[1] = A[y][1] ^ (~A[y][2] & A[y][3]);

        C[2] = A[y][2] ^ (~A[y][3] & A[y][4]);

        C[3] = A[y][3] ^ (~A[y][4] & A[y][0]);

        C[4] = A[y][4] ^ (~A[y][0] & A[y][1]);

        A[y][0] = C[0];

        A[y][1] = C[1];

        A[y][2] = C[2];

        A[y][3] = C[3];

        A[y][4] = C[4];

    }

}

static void Iota(uint64_t A[5][5], size_t i)

{

    static const uint64_t iotas[] = {

        0x0000000000000001U, 0x0000000000008082U, 0x800000000000808aU,

        0x8000000080008000U, 0x000000000000808bU, 0x0000000080000001U,

        0x8000000080008081U, 0x8000000000008009U, 0x000000000000008aU,

        0x0000000000000088U, 0x0000000080008009U, 0x000000008000000aU,

        0x000000008000808bU, 0x800000000000008bU, 0x8000000000008089U,

        0x8000000000008003U, 0x8000000000008002U, 0x8000000000000080U,

        0x000000000000800aU, 0x800000008000000aU, 0x8000000080008081U,

        0x8000000000008080U, 0x0000000080000001U, 0x8000000080008008U

    };

    assert(i < (sizeof(iotas) / sizeof(iotas[0])));

    A[0][0] ^= iotas[i];

}

void KeccakF1600(uint64_t A[5][5])

{

    size_t i;

    for (i = 0; i < 24; i++) {

        Theta(A);

        Rho(A);

        Pi(A);

        Chi(A);

        Iota(A, i);

    }

}

/*

 * SHA3_absorb can be called multiple times, but at each invocation

 * largest multiple of |r| out of |len| bytes are processed. Then

 * remaining amount of bytes are returned. This is done to spare caller

 * trouble of calculating the largest multiple of |r|, effectively the

 * blocksize. It is commonly (1600 - 256*n)/8, e.g. 168, 136, 104, 72,

 * but can also be (1600 - 448)/8 = 144. All this means that message

 * padding and intermediate sub-block buffering, byte- or bitwise, is

 * caller's reponsibility.

 */

size_t SHA3_absorb(uint64_t A[5][5], const unsigned char *inp, size_t len,

                   size_t r)

{

    uint64_t *A_flat = (uint64_t *)A;

    size_t i, w = r / 8;

    while (len >= r) {

        for (i = 0; i < w; i++) {

            A_flat[i] ^= (uint64_t)inp[0]       | (uint64_t)inp[1] << 8  |

                         (uint64_t)inp[2] << 16 | (uint64_t)inp[3] << 24 |

                         (uint64_t)inp[4] << 32 | (uint64_t)inp[5] << 40 |

                         (uint64_t)inp[6] << 48 | (uint64_t)inp[7] << 56;

            inp += 8;

        }

        KeccakF1600(A);

        len -= r;

    }

    return len;

}

/*

 * SHA3_squeeze is called once at the end to generate |out| hash value

 * of |len| bytes.

 */

void SHA3_squeeze(uint64_t A[5][5], unsigned char *out, size_t len, size_t r)

{

    uint64_t *A_flat = (uint64_t *)A;

    size_t i, rem, w = r / 8;

    while (len >= r) {

        for (i = 0; i < w; i++) {

            uint64_t Ai = A_flat[i];

            out[0] = (unsigned char)(Ai);

            out[1] = (unsigned char)(Ai >> 8);

            out[2] = (unsigned char)(Ai >> 16);

            out[3] = (unsigned char)(Ai >> 24);

            out[4] = (unsigned char)(Ai >> 32);

            out[5] = (unsigned char)(Ai >> 40);

            out[6] = (unsigned char)(Ai >> 48);

            out[7] = (unsigned char)(Ai >> 56);

            out += 8;

        }

        len -= r;

        if (len)

            KeccakF1600(A);

    }

    rem = len % 8;

    len /= 8;

    for (i = 0; i < len; i++) {

        uint64_t Ai = A_flat[i];

        out[0] = (unsigned char)(Ai);

        out[1] = (unsigned char)(Ai >> 8);

        out[2] = (unsigned char)(Ai >> 16);

        out[3] = (unsigned char)(Ai >> 24);

        out[4] = (unsigned char)(Ai >> 32);

        out[5] = (unsigned char)(Ai >> 40);

        out[6] = (unsigned char)(Ai >> 48);

        out[7] = (unsigned char)(Ai >> 56);

        out += 8;

    }

    if (rem) {

        uint64_t Ai = A_flat[i];

        for (i = 0; i < rem; i++) {

            *out++ = (unsigned char)Ai;

            Ai >>= 8;

        }

    }

}

#ifdef SELFTEST

/*

 * Post-padding one-shot implementations would look as following:

 *

 * SHA3_224     SHA3_sponge(inp, len, out, 224/8, (1600-448)/8);

 * SHA3_256     SHA3_sponge(inp, len, out, 256/8, (1600-512)/8);

 * SHA3_384     SHA3_sponge(inp, len, out, 384/8, (1600-768)/8);

 * SHA3_512     SHA3_sponge(inp, len, out, 512/8, (1600-1024)/8);

 * SHAKE_128    SHA3_sponge(inp, len, out, d, (1600-256)/8);

 * SHAKE_256    SHA3_sponge(inp, len, out, d, (1600-512)/8);

 */

void SHA3_sponge(const unsigned char *inp, size_t len,

                 unsigned char *out, size_t d, size_t r)

{

    uint64_t A[5][5];

    memset(A, 0, sizeof(A));

    SHA3_absorb(A, inp, len, r);

    SHA3_squeeze(A, out, d, r);

}

# include <stdio.h>

int main()

{

    unsigned char test[168] = { '\xf3', '\x3' };

    unsigned char out[512];

    size_t i;

    /*

     * This is 5-bit SHAKE128 test from http://csrc.nist.gov/groups/ST/toolkit/examples.html#aHashing

     */

    test[167] = '\x80';

    SHA3_sponge(test, sizeof(test), out, sizeof(out), sizeof(test));

    for (i = 0; i < sizeof(out);) {

        printf("%02X", out[i]);

        printf(++i % 16 && i != sizeof(out) ? " " : "\n");

    }

}

#endif