/*

 * Copyright 2016-2019 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 <openssl/e_os2.h>

#include <string.h>

#include <assert.h>

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

                   size_t r);

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

#if !defined(KECCAK1600_ASM) || !defined(SELFTEST)

/*

 * Choose some sensible defaults

 */

#if !defined(KECCAK_REF) && !defined(KECCAK_1X) && !defined(KECCAK_1X_ALT) && \

    !defined(KECCAK_2X) && !defined(KECCAK_INPLACE)

# define KECCAK_2X      /* default to KECCAK_2X variant */

#endif

#if defined(__i386) || defined(__i386__) || defined(_M_IX86)

# define KECCAK_COMPLEMENTING_TRANSFORM

#endif

#if defined(__x86_64__) || defined(__aarch64__) || \

    defined(__mips64) || defined(__ia64) || \

    (defined(__VMS) && !defined(__vax))

/*

 * These are available even in ILP32 flavours, but even then they are

 * capable of performing 64-bit operations as efficiently as in *P64.

 * Since it's not given that we can use sizeof(void *), just shunt it.

 */

# define BIT_INTERLEAVE (0)

#else

# define BIT_INTERLEAVE (sizeof(void *) < 8)

#endif

#define ROL32(a, offset) (((a) << (offset)) | ((a) >> ((32 - (offset)) & 31)))

static uint64_t ROL64(uint64_t val, int offset)

{

    if (offset == 0) {

        return val;

    } else if (!BIT_INTERLEAVE) {

        return (val << offset) | (val >> (64-offset));

    } else {

        uint32_t hi = (uint32_t)(val >> 32), lo = (uint32_t)val;

        if (offset & 1) {

            uint32_t tmp = hi;

            offset >>= 1;

            hi = ROL32(lo, offset);

            lo = ROL32(tmp, offset + 1);

        } else {

            offset >>= 1;

            lo = ROL32(lo, offset);

            hi = ROL32(hi, offset);

        }

        return ((uint64_t)hi << 32) | lo;

    }

}

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 }

};

static const uint64_t iotas[] = {

    BIT_INTERLEAVE ? 0x0000000000000001ULL : 0x0000000000000001ULL,

    BIT_INTERLEAVE ? 0x0000008900000000ULL : 0x0000000000008082ULL,

    BIT_INTERLEAVE ? 0x8000008b00000000ULL : 0x800000000000808aULL,

    BIT_INTERLEAVE ? 0x8000808000000000ULL : 0x8000000080008000ULL,

    BIT_INTERLEAVE ? 0x0000008b00000001ULL : 0x000000000000808bULL,

    BIT_INTERLEAVE ? 0x0000800000000001ULL : 0x0000000080000001ULL,

    BIT_INTERLEAVE ? 0x8000808800000001ULL : 0x8000000080008081ULL,

    BIT_INTERLEAVE ? 0x8000008200000001ULL : 0x8000000000008009ULL,

    BIT_INTERLEAVE ? 0x0000000b00000000ULL : 0x000000000000008aULL,

    BIT_INTERLEAVE ? 0x0000000a00000000ULL : 0x0000000000000088ULL,

    BIT_INTERLEAVE ? 0x0000808200000001ULL : 0x0000000080008009ULL,

    BIT_INTERLEAVE ? 0x0000800300000000ULL : 0x000000008000000aULL,

    BIT_INTERLEAVE ? 0x0000808b00000001ULL : 0x000000008000808bULL,

    BIT_INTERLEAVE ? 0x8000000b00000001ULL : 0x800000000000008bULL,

    BIT_INTERLEAVE ? 0x8000008a00000001ULL : 0x8000000000008089ULL,

    BIT_INTERLEAVE ? 0x8000008100000001ULL : 0x8000000000008003ULL,

    BIT_INTERLEAVE ? 0x8000008100000000ULL : 0x8000000000008002ULL,

    BIT_INTERLEAVE ? 0x8000000800000000ULL : 0x8000000000000080ULL,

    BIT_INTERLEAVE ? 0x0000008300000000ULL : 0x000000000000800aULL,

    BIT_INTERLEAVE ? 0x8000800300000000ULL : 0x800000008000000aULL,

    BIT_INTERLEAVE ? 0x8000808800000001ULL : 0x8000000080008081ULL,

    BIT_INTERLEAVE ? 0x8000008800000000ULL : 0x8000000000008080ULL,

    BIT_INTERLEAVE ? 0x0000800000000001ULL : 0x0000000080000001ULL,

    BIT_INTERLEAVE ? 0x8000808200000000ULL : 0x8000000080008008ULL

};

#if defined(KECCAK_REF)

/*

 * This is straightforward or "maximum clarity" implementation aiming

 * to resemble section 3.2 of the FIPS PUB 202 "SHA-3 Standard:

 * Permutation-Based Hash and Extendible-Output Functions" as much as

 * possible. With one caveat. Because of the way C stores matrices,

 * references to A[x,y] in the specification are presented as A[y][x].

 * Implementation unrolls inner x-loops so that modulo 5 operations are

 * explicitly pre-computed.

 */

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

{

    uint64_t C[5], D[5];

    size_t y;

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

    C[1] = A[0][1];

    C[2] = A[0][2];

    C[3] = A[0][3];

    C[4] = A[0][4];

    for (y = 1; y < 5; y++) {

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

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

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

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

        C[4] ^= A[y][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])

{

    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)

{

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

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

}

static 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);

    }

}

#elif defined(KECCAK_1X)

/*

 * This implementation is optimization of above code featuring unroll

 * of even y-loops, their fusion and code motion. It also minimizes

 * temporary storage. Compiler would normally do all these things for

 * you, purpose of manual optimization is to provide "unobscured"

 * reference for assembly implementation [in case this approach is

 * chosen for implementation on some platform]. In the nutshell it's

 * equivalent of "plane-per-plane processing" approach discussed in

 * section 2.4 of "Keccak implementation overview".

 */

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

{

    uint64_t C[5], E[2];        /* registers */

    uint64_t D[5], T[2][5];     /* memory    */

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

    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];

#if defined(__arm__)

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

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

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

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

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

    T[0][0] = A[3][0] ^ C[0]; /* borrow T[0][0] */

    T[0][1] = A[0][1] ^ E[0]; /* D[1] */

    T[0][2] = A[0][2] ^ C[1]; /* D[2] */

    T[0][3] = A[0][3] ^ C[2]; /* D[3] */

    T[0][4] = A[0][4] ^ E[1]; /* D[4] */

    C[3] = ROL64(A[3][3] ^ C[2], rhotates[3][3]);   /* D[3] */

    C[4] = ROL64(A[4][4] ^ E[1], rhotates[4][4]);   /* D[4] */

    C[0] =       A[0][0] ^ C[0]; /* rotate by 0 */  /* D[0] */

    C[2] = ROL64(A[2][2] ^ C[1], rhotates[2][2]);   /* D[2] */

    C[1] = ROL64(A[1][1] ^ E[0], rhotates[1][1]);   /* D[1] */

#else

    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];

    T[0][0] = A[3][0] ^ D[0]; /* borrow T[0][0] */

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

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

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

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

    C[0] =       A[0][0] ^ D[0]; /* rotate by 0 */

    C[1] = ROL64(A[1][1] ^ D[1], rhotates[1][1]);

    C[2] = ROL64(A[2][2] ^ D[2], rhotates[2][2]);

    C[3] = ROL64(A[3][3] ^ D[3], rhotates[3][3]);

    C[4] = ROL64(A[4][4] ^ D[4], rhotates[4][4]);

#endif

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

    A[0][1] = C[1] ^ (~C[2] & C[3]);

    A[0][2] = C[2] ^ (~C[3] & C[4]);

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

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

    T[1][0] = A[1][0] ^ (C[3] = D[0]);

    T[1][1] = A[2][1] ^ (C[4] = D[1]); /* borrow T[1][1] */

    T[1][2] = A[1][2] ^ (E[0] = D[2]);

    T[1][3] = A[1][3] ^ (E[1] = D[3]);

    T[1][4] = A[2][4] ^ (C[2] = D[4]); /* borrow T[1][4] */

    C[0] = ROL64(T[0][3],        rhotates[0][3]);

    C[1] = ROL64(A[1][4] ^ C[2], rhotates[1][4]);   /* D[4] */

    C[2] = ROL64(A[2][0] ^ C[3], rhotates[2][0]);   /* D[0] */

    C[3] = ROL64(A[3][1] ^ C[4], rhotates[3][1]);   /* D[1] */

    C[4] = ROL64(A[4][2] ^ E[0], rhotates[4][2]);   /* D[2] */

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

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

    A[1][2] = C[2] ^ (~C[3] & C[4]);

    A[1][3] = C[3] ^ (~C[4] & C[0]);

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

    C[0] = ROL64(T[0][1],        rhotates[0][1]);

    C[1] = ROL64(T[1][2],        rhotates[1][2]);

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

    C[3] = ROL64(A[3][4] ^ D[4], rhotates[3][4]);

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

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

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

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

    A[2][3] = C[3] ^ (~C[4] & C[0]);

    A[2][4] = C[4] ^ (~C[0] & C[1]);

    C[0] = ROL64(T[0][4],        rhotates[0][4]);

    C[1] = ROL64(T[1][0],        rhotates[1][0]);

    C[2] = ROL64(T[1][1],        rhotates[2][1]); /* originally A[2][1] */

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

    C[4] = ROL64(A[4][3] ^ D[3], rhotates[4][3]);

    A[3][0] = C[0] ^ (~C[1] & C[2]);

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

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

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

    A[3][4] = C[4] ^ (~C[0] & C[1]);

    C[0] = ROL64(T[0][2],        rhotates[0][2]);

    C[1] = ROL64(T[1][3],        rhotates[1][3]);

    C[2] = ROL64(T[1][4],        rhotates[2][4]); /* originally A[2][4] */

    C[3] = ROL64(T[0][0],        rhotates[3][0]); /* originally A[3][0] */

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

    A[4][0] = C[0] ^ (~C[1] & C[2]);

    A[4][1] = C[1] ^ (~C[2] & C[3]);

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

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

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

}

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

{

    size_t i;

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

        Round(A, i);

    }

}

#elif defined(KECCAK_1X_ALT)

/*

 * This is variant of above KECCAK_1X that reduces requirement for

 * temporary storage even further, but at cost of more updates to A[][].

 * It's less suitable if A[][] is memory bound, but better if it's

 * register bound.

 */

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

{

    uint64_t C[5], D[5];

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

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

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

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

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

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

    A[0][1] ^= D[1];

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

    A[2][1] ^= D[1];

    A[3][1] ^= D[1];

    A[4][1] ^= D[1];

    A[0][2] ^= D[2];

    A[1][2] ^= D[2];

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

    A[3][2] ^= D[2];

    A[4][2] ^= D[2];

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

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

    A[2][3] ^= C[2];

    A[3][3] ^= C[2];

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

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

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

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

    A[3][4] ^= C[3];

    A[4][4] ^= C[3];

    A[0][0] ^= C[4];

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

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

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

    A[4][0] ^= C[4];

    C[1] = A[0][1];

    C[2] = A[0][2];

    C[3] = A[0][3];

    C[4] = A[0][4];

    A[0][1] = ROL64(A[1][1], rhotates[1][1]);

    A[0][2] = ROL64(A[2][2], rhotates[2][2]);

    A[0][3] = ROL64(A[3][3], rhotates[3][3]);

    A[0][4] = ROL64(A[4][4], rhotates[4][4]);

    A[1][1] = ROL64(A[1][4], rhotates[1][4]);

    A[2][2] = ROL64(A[2][3], rhotates[2][3]);

    A[3][3] = ROL64(A[3][2], rhotates[3][2]);

    A[4][4] = ROL64(A[4][1], rhotates[4][1]);

    A[1][4] = ROL64(A[4][2], rhotates[4][2]);

    A[2][3] = ROL64(A[3][4], rhotates[3][4]);

    A[3][2] = ROL64(A[2][1], rhotates[2][1]);

    A[4][1] = ROL64(A[1][3], rhotates[1][3]);

    A[4][2] = ROL64(A[2][4], rhotates[2][4]);

    A[3][4] = ROL64(A[4][3], rhotates[4][3]);

    A[2][1] = ROL64(A[1][2], rhotates[1][2]);

    A[1][3] = ROL64(A[3][1], rhotates[3][1]);

    A[2][4] = ROL64(A[4][0], rhotates[4][0]);

    A[4][3] = ROL64(A[3][0], rhotates[3][0]);

    A[1][2] = ROL64(A[2][0], rhotates[2][0]);

    A[3][1] = ROL64(A[1][0], rhotates[1][0]);

    A[1][0] = ROL64(C[3],    rhotates[0][3]);

    A[2][0] = ROL64(C[1],    rhotates[0][1]);

    A[3][0] = ROL64(C[4],    rhotates[0][4]);

    A[4][0] = ROL64(C[2],    rhotates[0][2]);

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

    C[1] = A[1][0];

    D[0] = A[0][1];

    D[1] = A[1][1];

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

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

    A[0][1] ^= (~A[0][2] & A[0][3]);

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

    A[0][2] ^= (~A[0][3] & A[0][4]);

    A[1][2] ^= (~A[1][3] & A[1][4]);

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

    A[1][3] ^= (~A[1][4] & C[1]);

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

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

    C[2] = A[2][0];

    C[3] = A[3][0];

    D[2] = A[2][1];

    D[3] = A[3][1];

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

    A[3][0] ^= (~A[3][1] & A[3][2]);

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

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

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

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

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

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

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

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

    C[4] = A[4][0];

    D[4] = A[4][1];

    A[4][0] ^= (~A[4][1] & A[4][2]);

    A[4][1] ^= (~A[4][2] & A[4][3]);

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

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

    A[4][4] ^= (~C[4]    & D[4]);

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

}

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

{

    size_t i;

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

        Round(A, i);

    }

}

#elif defined(KECCAK_2X)

/*

 * This implementation is variant of KECCAK_1X above with outer-most

 * round loop unrolled twice. This allows to take temporary storage

 * out of round procedure and simplify references to it by alternating

 * it with actual data (see round loop below). Originally it was meant

 * rather as reference for an assembly implementation, but it seems to

 * play best with compilers [as well as provide best instruction per

 * processed byte ratio at minimal round unroll factor]...

 */

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

{

    uint64_t C[5], D[5];

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

    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];

    C[0] =       A[0][0] ^ D[0]; /* rotate by 0 */

    C[1] = ROL64(A[1][1] ^ D[1], rhotates[1][1]);

    C[2] = ROL64(A[2][2] ^ D[2], rhotates[2][2]);

    C[3] = ROL64(A[3][3] ^ D[3], rhotates[3][3]);

    C[4] = ROL64(A[4][4] ^ D[4], rhotates[4][4]);

#ifdef KECCAK_COMPLEMENTING_TRANSFORM

    R[0][0] = C[0] ^ ( C[1] | C[2]) ^ iotas[i];

    R[0][1] = C[1] ^ (~C[2] | C[3]);

    R[0][2] = C[2] ^ ( C[3] & C[4]);

    R[0][3] = C[3] ^ ( C[4] | C[0]);

    R[0][4] = C[4] ^ ( C[0] & C[1]);

#else

    R[0][0] = C[0] ^ (~C[1] & C[2]) ^ iotas[i];

    R[0][1] = C[1] ^ (~C[2] & C[3]);

    R[0][2] = C[2] ^ (~C[3] & C[4]);

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

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

#endif

    C[0] = ROL64(A[0][3] ^ D[3], rhotates[0][3]);

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

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

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

    C[4] = ROL64(A[4][2] ^ D[2], rhotates[4][2]);

#ifdef KECCAK_COMPLEMENTING_TRANSFORM

    R[1][0] = C[0] ^ (C[1] |  C[2]);

    R[1][1] = C[1] ^ (C[2] &  C[3]);

    R[1][2] = C[2] ^ (C[3] | ~C[4]);

    R[1][3] = C[3] ^ (C[4] |  C[0]);

    R[1][4] = C[4] ^ (C[0] &  C[1]);

#else

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

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

    R[1][2] = C[2] ^ (~C[3] & C[4]);

    R[1][3] = C[3] ^ (~C[4] & C[0]);

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

#endif

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

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

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

    C[3] = ROL64(A[3][4] ^ D[4], rhotates[3][4]);

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

#ifdef KECCAK_COMPLEMENTING_TRANSFORM

    R[2][0] =  C[0] ^ ( C[1] | C[2]);

    R[2][1] =  C[1] ^ ( C[2] & C[3]);

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

    R[2][3] = ~C[3] ^ ( C[4] | C[0]);

    R[2][4] =  C[4] ^ ( C[0] & C[1]);

#else

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

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

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

    R[2][3] = C[3] ^ (~C[4] & C[0]);

    R[2][4] = C[4] ^ (~C[0] & C[1]);

#endif

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

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

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

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

    C[4] = ROL64(A[4][3] ^ D[3], rhotates[4][3]);

#ifdef KECCAK_COMPLEMENTING_TRANSFORM

    R[3][0] =  C[0] ^ ( C[1] & C[2]);

    R[3][1] =  C[1] ^ ( C[2] | C[3]);

    R[3][2] =  C[2] ^ (~C[3] | C[4]);

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

    R[3][4] =  C[4] ^ ( C[0] | C[1]);

#else

    R[3][0] = C[0] ^ (~C[1] & C[2]);

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

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

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

    R[3][4] = C[4] ^ (~C[0] & C[1]);

#endif

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

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

    C[2] = ROL64(A[2][4] ^ D[4], rhotates[2][4]);

    C[3] = ROL64(A[3][0] ^ D[0], rhotates[3][0]);

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

#ifdef KECCAK_COMPLEMENTING_TRANSFORM

    R[4][0] =  C[0] ^ (~C[1] & C[2]);

    R[4][1] = ~C[1] ^ ( C[2] | C[3]);

    R[4][2] =  C[2] ^ ( C[3] & C[4]);

    R[4][3] =  C[3] ^ ( C[4] | C[0]);

    R[4][4] =  C[4] ^ ( C[0] & C[1]);

#else

    R[4][0] = C[0] ^ (~C[1] & C[2]);

    R[4][1] = C[1] ^ (~C[2] & C[3]);

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

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

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

#endif

}

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

{

    uint64_t T[5][5];

    size_t i;

#ifdef KECCAK_COMPLEMENTING_TRANSFORM

    A[0][1] = ~A[0][1];

    A[0][2] = ~A[0][2];

    A[1][3] = ~A[1][3];

    A[2][2] = ~A[2][2];

    A[3][2] = ~A[3][2];

    A[4][0] = ~A[4][0];

#endif

    for (i = 0; i < 24; i += 2) {

        Round(T, A, i);

        Round(A, T, i + 1);

    }

#ifdef KECCAK_COMPLEMENTING_TRANSFORM

    A[0][1] = ~A[0][1];

    A[0][2] = ~A[0][2];

    A[1][3] = ~A[1][3];

    A[2][2] = ~A[2][2];

    A[3][2] = ~A[3][2];

    A[4][0] = ~A[4][0];

#endif

}

#else   /* define KECCAK_INPLACE to compile this code path */

/*

 * This implementation is KECCAK_1X from above combined 4 times with

 * a twist that allows to omit temporary storage and perform in-place

 * processing. It's discussed in section 2.5 of "Keccak implementation

 * overview". It's likely to be best suited for processors with large

 * register bank... On the other hand processor with large register

 * bank can as well use KECCAK_1X_ALT, it would be as fast but much

 * more compact...

 */

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

{

    uint64_t B[5], C[5], D[5];

    assert(i <= (sizeof(iotas) / sizeof(iotas[0]) - 4));

    /* Round 4*n */

    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];

    B[0] =       A[0][0] ^ D[0]; /* rotate by 0 */

    B[1] = ROL64(A[1][1] ^ D[1], rhotates[1][1]);

    B[2] = ROL64(A[2][2] ^ D[2], rhotates[2][2]);

    B[3] = ROL64(A[3][3] ^ D[3], rhotates[3][3]);

    B[4] = ROL64(A[4][4] ^ D[4], rhotates[4][4]);

    C[0] = A[0][0] = B[0] ^ (~B[1] & B[2]) ^ iotas[i];

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

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

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

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

    B[0] = ROL64(A[0][3] ^ D[3], rhotates[0][3]);

    B[1] = ROL64(A[1][4] ^ D[4], rhotates[1][4]);

    B[2] = ROL64(A[2][0] ^ D[0], rhotates[2][0]);

    B[3] = ROL64(A[3][1] ^ D[1], rhotates[3][1]);

    B[4] = ROL64(A[4][2] ^ D[2], rhotates[4][2]);

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

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

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

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

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

    B[0] = ROL64(A[0][1] ^ D[1], rhotates[0][1]);

    B[1] = ROL64(A[1][2] ^ D[2], rhotates[1][2]);

    B[2] = ROL64(A[2][3] ^ D[3], rhotates[2][3]);

    B[3] = ROL64(A[3][4] ^ D[4], rhotates[3][4]);

    B[4] = ROL64(A[4][0] ^ D[0], rhotates[4][0]);

    C[0] ^= A[4][0] = B[0] ^ (~B[1] & B[2]);

    C[1] ^= A[0][1] = B[1] ^ (~B[2] & B[3]);

    C[2] ^= A[1][2] = B[2] ^ (~B[3] & B[4]);

    C[3] ^= A[2][3] = B[3] ^ (~B[4] & B[0]);

    C[4] ^= A[3][4] = B[4] ^ (~B[0] & B[1]);

    B[0] = ROL64(A[0][4] ^ D[4], rhotates[0][4]);

    B[1] = ROL64(A[1][0] ^ D[0], rhotates[1][0]);

    B[2] = ROL64(A[2][1] ^ D[1], rhotates[2][1]);

    B[3] = ROL64(A[3][2] ^ D[2], rhotates[3][2]);

    B[4] = ROL64(A[4][3] ^ D[3], rhotates[4][3]);

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

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

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

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

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

    B[0] = ROL64(A[0][2] ^ D[2], rhotates[0][2]);

    B[1] = ROL64(A[1][3] ^ D[3], rhotates[1][3]);

    B[2] = ROL64(A[2][4] ^ D[4], rhotates[2][4]);

    B[3] = ROL64(A[3][0] ^ D[0], rhotates[3][0]);

    B[4] = ROL64(A[4][1] ^ D[1], rhotates[4][1]);

    C[0] ^= A[3][0] = B[0] ^ (~B[1] & B[2]);

    C[1] ^= A[4][1] = B[1] ^ (~B[2] & B[3]);

    C[2] ^= A[0][2] = B[2] ^ (~B[3] & B[4]);

    C[3] ^= A[1][3] = B[3] ^ (~B[4] & B[0]);

    C[4] ^= A[2][4] = B[4] ^ (~B[0] & B[1]);

    /* Round 4*n+1 */

    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];

    B[0] =       A[0][0] ^ D[0]; /* rotate by 0 */

    B[1] = ROL64(A[3][1] ^ D[1], rhotates[1][1]);

    B[2] = ROL64(A[1][2] ^ D[2], rhotates[2][2]);

    B[3] = ROL64(A[4][3] ^ D[3], rhotates[3][3]);

    B[4] = ROL64(A[2][4] ^ D[4], rhotates[4][4]);

    C[0] = A[0][0] = B[0] ^ (~B[1] & B[2]) ^ iotas[i + 1];

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

    C[2] = A[1][2] = B[2] ^ (~B[3] & B[4]);

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

    C[4] = A[2][4] = B[4] ^ (~B[0] & B[1]);

    B[0] = ROL64(A[3][3] ^ D[3], rhotates[0][3]);

    B[1] = ROL64(A[1][4] ^ D[4], rhotates[1][4]);

    B[2] = ROL64(A[4][0] ^ D[0], rhotates[2][0]);

    B[3] = ROL64(A[2][1] ^ D[1], rhotates[3][1]);

    B[4] = ROL64(A[0][2] ^ D[2], rhotates[4][2]);

    C[0] ^= A[4][0] = B[0] ^ (~B[1] & B[2]);

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

    C[2] ^= A[0][2] = B[2] ^ (~B[3] & B[4]);

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

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

    B[0] = ROL64(A[1][1] ^ D[1], rhotates[0][1]);

    B[1] = ROL64(A[4][2] ^ D[2], rhotates[1][2]);

    B[2] = ROL64(A[2][3] ^ D[3], rhotates[2][3]);

    B[3] = ROL64(A[0][4] ^ D[4], rhotates[3][4]);

    B[4] = ROL64(A[3][0] ^ D[0], rhotates[4][0]);

    C[0] ^= A[3][0] = B[0] ^ (~B[1] & B[2]);

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

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

    C[3] ^= A[2][3] = B[3] ^ (~B[4] & B[0]);

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

    B[0] = ROL64(A[4][4] ^ D[4], rhotates[0][4]);

    B[1] = ROL64(A[2][0] ^ D[0], rhotates[1][0]);

    B[2] = ROL64(A[0][1] ^ D[1], rhotates[2][1]);

    B[3] = ROL64(A[3][2] ^ D[2], rhotates[3][2]);

    B[4] = ROL64(A[1][3] ^ D[3], rhotates[4][3]);

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

    C[1] ^= A[0][1] = B[1] ^ (~B[2] & B[3]);

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

    C[3] ^= A[1][3] = B[3] ^ (~B[4] & B[0]);

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

    B[0] = ROL64(A[2][2] ^ D[2], rhotates[0][2]);

    B[1] = ROL64(A[0][3] ^ D[3], rhotates[1][3]);

    B[2] = ROL64(A[3][4] ^ D[4], rhotates[2][4]);

    B[3] = ROL64(A[1][0] ^ D[0], rhotates[3][0]);

    B[4] = ROL64(A[4][1] ^ D[1], rhotates[4][1]);

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

    C[1] ^= A[4][1] = B[1] ^ (~B[2] & B[3]);

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

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

    C[4] ^= A[3][4] = B[4] ^ (~B[0] & B[1]);

    /* Round 4*n+2 */

    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];

    B[0] =       A[0][0] ^ D[0]; /* rotate by 0 */

    B[1] = ROL64(A[2][1] ^ D[1], rhotates[1][1]);

    B[2] = ROL64(A[4][2] ^ D[2], rhotates[2][2]);

    B[3] = ROL64(A[1][3] ^ D[3], rhotates[3][3]);

    B[4] = ROL64(A[3][4] ^ D[4], rhotates[4][4]);

    C[0] = A[0][0] = B[0] ^ (~B[1] & B[2]) ^ iotas[i + 2];

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

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

    C[3] = A[1][3] = B[3] ^ (~B[4] & B[0]);

    C[4] = A[3][4] = B[4] ^ (~B[0] & B[1]);

    B[0] = ROL64(A[4][3] ^ D[3], rhotates[0][3]);

    B[1] = ROL64(A[1][4] ^ D[4], rhotates[1][4]);

    B[2] = ROL64(A[3][0] ^ D[0], rhotates[2][0]);

    B[3] = ROL64(A[0][1] ^ D[1], rhotates[3][1]);

    B[4] = ROL64(A[2][2] ^ D[2], rhotates[4][2]);

    C[0] ^= A[3][0] = B[0] ^ (~B[1] & B[2]);

    C[1] ^= A[0][1] = B[1] ^ (~B[2] & B[3]);

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

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

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

    B[0] = ROL64(A[3][1] ^ D[1], rhotates[0][1]);

    B[1] = ROL64(A[0][2] ^ D[2], rhotates[1][2]);

    B[2] = ROL64(A[2][3] ^ D[3], rhotates[2][3]);

    B[3] = ROL64(A[4][4] ^ D[4], rhotates[3][4]);

    B[4] = ROL64(A[1][0] ^ D[0], rhotates[4][0]);

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

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

    C[2] ^= A[0][2] = B[2] ^ (~B[3] & B[4]);

    C[3] ^= A[2][3] = B[3] ^ (~B[4] & B[0]);

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

    B[0] = ROL64(A[2][4] ^ D[4], rhotates[0][4]);

    B[1] = ROL64(A[4][0] ^ D[0], rhotates[1][0]);

    B[2] = ROL64(A[1][1] ^ D[1], rhotates[2][1]);

    B[3] = ROL64(A[3][2] ^ D[2], rhotates[3][2]);

    B[4] = ROL64(A[0][3] ^ D[3], rhotates[4][3]);