#include <string.h>
#include <stdlib.h>
#include "brg_endian.h"
#include "KeccakP-1600-SnP.h"
#include "SnP-Relaned.h"

#define USE_MEMSET
/* #define DIVISION_INSTRUCTION */ /* comment if no division instruction or more compact when not using division */
#define UNROLL_CHILOOP        /* comment more compact using for loop */

typedef unsigned char UINT8;
typedef unsigned long long int UINT64;
typedef unsigned int tSmallUInt; /*INFO It could be more optimized to use "unsigned char" on an 8-bit CPU    */
typedef UINT64 tKeccakLane;

#if defined(_MSC_VER)
#define ROL64(a, offset) _rotl64(a, offset)
#elif defined(UseSHLD)
    #define ROL64(x,N) ({ \
    register UINT64 __out; \
    register UINT64 __in = x; \
    __asm__ ("shld %2,%0,%0" : "=r"(__out) : "0"(__in), "i"(N)); \
    __out; \
    })
#else
#define ROL64(a, offset) ((((UINT64)a) << offset) ^ (((UINT64)a) >> (64-offset)))
#endif

#define    cKeccakNumberOfRounds    24

const UINT8 KeccakP1600_RotationConstants[25] =
{
     1,  3,  6, 10, 15, 21, 28, 36, 45, 55,  2, 14, 27, 41, 56,  8, 25, 43, 62, 18, 39, 61, 20, 44
};

const UINT8 KeccakP1600_PiLane[25] =
{
    10,  7, 11, 17, 18,  3,  5, 16,  8, 21, 24,  4, 15, 23, 19, 13, 12,  2, 20, 14, 22,  9,  6,  1
};

#if    defined(DIVISION_INSTRUCTION)
#define    MOD5(argValue)    ((argValue) % 5)
#else
const UINT8 KeccakP1600_Mod5[10] =
{
    0, 1, 2, 3, 4, 0, 1, 2, 3, 4
};
#define    MOD5(argValue)    KeccakP1600_Mod5[argValue]
#endif

/* ---------------------------------------------------------------- */

static tKeccakLane KeccakF1600_GetNextRoundConstant( UINT8 *LFSR );
static tKeccakLane KeccakF1600_GetNextRoundConstant( UINT8 *LFSR )
{
    tSmallUInt i;
    tKeccakLane    roundConstant;
    tSmallUInt doXOR;
    tSmallUInt tempLSFR;

    roundConstant = 0;
    tempLSFR = *LFSR;
    for(i=1; i<128; i <<= 1)
    {
        doXOR = tempLSFR & 1;
        if ((tempLSFR & 0x80) != 0)
            /* Primitive polynomial over GF(2): x^8+x^6+x^5+x^4+1 */
            tempLSFR = (tempLSFR << 1) ^ 0x71;
        else
            tempLSFR <<= 1;

        if ( doXOR != 0 )
            roundConstant ^= (tKeccakLane)1ULL << (i - 1);
    }
    *LFSR = (UINT8)tempLSFR;
    return ( roundConstant );
}

/* ---------------------------------------------------------------- */

void KeccakP1600_Initialize(void *argState)
{
    #if defined(USE_MEMSET)
    memset( argState, 0, 25 * 8 );
    #else
    tSmallUInt i;
    tKeccakLane *state;

    state = argState;
    i = 25;
    do
    {
        *(state++) = 0;
    }
    while ( --i != 0 );
    #endif
}

/* ---------------------------------------------------------------- */

void KeccakP1600_AddBytesInLane(void *argState, unsigned int lanePosition, const unsigned char *data, unsigned int offset, unsigned int length)
{
    unsigned int i;
    #if (PLATFORM_BYTE_ORDER == IS_LITTLE_ENDIAN)
    unsigned char * state = (unsigned char*)argState + lanePosition * sizeof(tKeccakLane) + offset;
    for(i=0; i<length; i++)
        ((unsigned char *)state)[i] ^= data[i];
    #else
    tKeccakLane lane = 0;
    for(i=0; i<length; i++)
        lane |= ((tKeccakLane)data[i]) << ((i+offset)*8);
    ((tKeccakLane*)argState)[lanePosition] ^= lane;
    #endif
}

/* ---------------------------------------------------------------- */

void KeccakP1600_AddLanes(void *state, const unsigned char *data, unsigned int laneCount)
{
#if (PLATFORM_BYTE_ORDER == IS_LITTLE_ENDIAN)
    tSmallUInt i;
    laneCount *= sizeof(tKeccakLane);
    for( i = 0; i < laneCount; ++i) {
        ((unsigned char*)state)[i] ^= data[i];
    }
#else
    tSmallUInt i;
    const UINT8 *curData = data;
    for(i=0; i<laneCount; i++, curData+=8) {
        tKeccakLane lane = (tKeccakLane)curData[0]
            | ((tKeccakLane)curData[1] << 8)
            | ((tKeccakLane)curData[2] << 16)
            | ((tKeccakLane)curData[3] << 24)
            | ((tKeccakLane)curData[4] << 32)
            | ((tKeccakLane)curData[5] << 40)
            | ((tKeccakLane)curData[6] << 48)
            | ((tKeccakLane)curData[7] << 56);
        ((tKeccakLane*)state)[i] ^= lane;
    }
#endif
}

/* ---------------------------------------------------------------- */

void KeccakP1600_AddByte(void *state, unsigned char byte, unsigned int offset)
{
    UINT64 lane = byte;
    lane <<= (offset%8)*8;
    ((UINT64*)state)[offset/8] ^= lane;
}

/* ---------------------------------------------------------------- */

void KeccakP1600_AddBytes(void *state, const unsigned char *data, unsigned int offset, unsigned int length)
{
    SnP_AddBytes(state, data, offset, length, KeccakP1600_AddLanes, KeccakP1600_AddBytesInLane, 8);
}

/* ---------------------------------------------------------------- */

void KeccakP1600_OverwriteBytesInLane(void *argState, unsigned int lanePosition, const unsigned char *data, unsigned int offset, unsigned int length)
{
#if (PLATFORM_BYTE_ORDER == IS_LITTLE_ENDIAN)
    memcpy((unsigned char*)argState+lanePosition*8+offset, data, length);
#else
    unsigned int i;
    tKeccakLane *state = (tKeccakLane*)argState;
    tKeccakLane lane = state[lanePosition];
    for(i=0; i<length; i++) {
        lane &= ~(((tKeccakLane)0xFF) << ((i+offset)*8));
        lane |= ((tKeccakLane)data[i]) << ((i+offset)*8);
    }
    state[lanePosition] = lane;
#endif
}

/* ---------------------------------------------------------------- */

void KeccakP1600_OverwriteLanes(void *state, const unsigned char *data, unsigned int laneCount)
{
#if (PLATFORM_BYTE_ORDER == IS_LITTLE_ENDIAN)
    memcpy((unsigned char*)state, data, laneCount*8);
#else
    tSmallUInt i;
    const UINT8 *curData = data;
    for(i=0; i<laneCount; i++, curData+=8) {
        tKeccakLane lane = (tKeccakLane)curData[0]
            | ((tKeccakLane)curData[1] << 8)
            | ((tKeccakLane)curData[2] << 16)
            | ((tKeccakLane)curData[3] << 24)
            | ((tKeccakLane)curData[4] << 32)
            | ((tKeccakLane)curData[5] << 40)
            | ((tKeccakLane)curData[6] << 48)
            | ((tKeccakLane)curData[7] << 56);
        ((tKeccakLane*)state)[i] = lane;
    }
#endif
}

/* ---------------------------------------------------------------- */

void KeccakP1600_OverwriteBytes(void *state, const unsigned char *data, unsigned int offset, unsigned int length)
{
    SnP_OverwriteBytes(state, data, offset, length, KeccakP1600_OverwriteLanes, KeccakP1600_OverwriteBytesInLane, 8);
}

/* ---------------------------------------------------------------- */

void KeccakP1600_OverwriteWithZeroes(void *argState, unsigned int byteCount)
{
#if (PLATFORM_BYTE_ORDER == IS_LITTLE_ENDIAN)
    memset((unsigned char*)argState, 0, byteCount);
#else
    tKeccakLane *state = (tKeccakLane*)argState;
    unsigned int i, j;
    for(i=0; i<byteCount/8; i++)
        state[i] = 0;
    for(j=0; j<byteCount%8; j++)
        state[i] &= ~(((tKeccakLane)0xFF) << (j*8));
#endif
}

/* ---------------------------------------------------------------- */

static void KeccakP1600_Permute_NroundsLFSR(void *argState, UINT8 rounds, UINT8 LFSRinitialState)
{
    tSmallUInt x, y, round;
    tKeccakLane        temp;
    tKeccakLane        BC[5];
    tKeccakLane     *state;
    UINT8           LFSRstate;

    state = (tKeccakLane*)argState;
    LFSRstate = LFSRinitialState;
    round = rounds;
    do
    {
        /* Theta */
        for ( x = 0; x < 5; ++x )
        {
            BC[x] = state[x] ^ state[5 + x] ^ state[10 + x] ^ state[15 + x] ^ state[20 + x];
        }
        for ( x = 0; x < 5; ++x )
        {
            temp = BC[MOD5(x+4)] ^ ROL64(BC[MOD5(x+1)], 1);
            for ( y = 0; y < 25; y += 5 )
            {
                state[y + x] ^= temp;
            }
        }

        /* Rho Pi */
        temp = state[1];
        for ( x = 0; x < 24; ++x )
        {
            BC[0] = state[KeccakP1600_PiLane[x]];
            state[KeccakP1600_PiLane[x]] = ROL64( temp, KeccakP1600_RotationConstants[x] );
            temp = BC[0];
        }

        /*    Chi */
        for ( y = 0; y < 25; y += 5 )
        {
#if defined(UNROLL_CHILOOP)
            BC[0] = state[y + 0];
            BC[1] = state[y + 1];
            BC[2] = state[y + 2];
            BC[3] = state[y + 3];
            BC[4] = state[y + 4];
#else
            for ( x = 0; x < 5; ++x )
            {
                BC[x] = state[y + x];
            }
#endif
            for ( x = 0; x < 5; ++x )
            {
                state[y + x] = BC[x] ^((~BC[MOD5(x+1)]) & BC[MOD5(x+2)]);
            }
        }

        /*    Iota */
        state[0] ^= KeccakF1600_GetNextRoundConstant(&LFSRstate);
    }
    while( --round != 0 );
}

/* ---------------------------------------------------------------- */

void KeccakP1600_Permute_Nrounds(void *state, unsigned int nrounds)
{
	UINT8 LFSRstate;
	UINT8 nr;

	LFSRstate = 0x01;
	for ( nr = 24 - nrounds; nr != 0; --nr )
        KeccakF1600_GetNextRoundConstant(&LFSRstate);
    KeccakP1600_Permute_NroundsLFSR(state, nrounds, LFSRstate);
}

/* ---------------------------------------------------------------- */

void KeccakP1600_Permute_12rounds(void *state)
{
    KeccakP1600_Permute_NroundsLFSR(state, 12, 0xD5);
}

/* ---------------------------------------------------------------- */

void KeccakP1600_Permute_24rounds(void *state)
{
    KeccakP1600_Permute_NroundsLFSR(state, 24, 0x01);
}

/* ---------------------------------------------------------------- */

void KeccakP1600_ExtractBytesInLane(const void *state, unsigned int lanePosition, unsigned char *data, unsigned int offset, unsigned int length)
{
#if (PLATFORM_BYTE_ORDER == IS_LITTLE_ENDIAN)
    memcpy(data, ((UINT8*)&((tKeccakLane*)state)[lanePosition])+offset, length);
#else
    tSmallUInt i;
    tKeccakLane lane = ((tKeccakLane*)state)[lanePosition];
    lane >>= offset*8;
    for(i=0; i<length; i++) {
        data[i] = lane & 0xFF;
        lane >>= 8;
    }
#endif
}

/* ---------------------------------------------------------------- */

void KeccakP1600_ExtractLanes(const void *state, unsigned char *data, unsigned int laneCount)
{
#if (PLATFORM_BYTE_ORDER == IS_LITTLE_ENDIAN)
    memcpy(data, state, laneCount*8);
#else
    tSmallUInt i, j;
    for(i=0; i<laneCount; i++)
    {
        for(j=0; j<(64/8); j++)
        {
            data[(i*8)+j] = (((const tKeccakLane*)state)[i] >> (8*j)) & 0xFF;
        }
    }
#endif
}

/* ---------------------------------------------------------------- */

void KeccakP1600_ExtractBytes(const void *state, unsigned char *data, unsigned int offset, unsigned int length)
{
    SnP_ExtractBytes(state, data, offset, length, KeccakP1600_ExtractLanes, KeccakP1600_ExtractBytesInLane, 8);
}

/* ---------------------------------------------------------------- */

void KeccakP1600_ExtractAndAddBytesInLane(const void *state, unsigned int lanePosition, const unsigned char *input, unsigned char *output, unsigned int offset, unsigned int length)
{
    tSmallUInt i;
    tKeccakLane lane = ((tKeccakLane*)state)[lanePosition];
    lane >>= offset*8;
    for(i=0; i<length; i++) {
        output[i] = input[i] ^ (lane & 0xFF);
        lane >>= 8;
    }
}

/* ---------------------------------------------------------------- */

void KeccakP1600_ExtractAndAddLanes(const void *state, const unsigned char *input, unsigned char *output, unsigned int laneCount)
{
#if (PLATFORM_BYTE_ORDER == IS_LITTLE_ENDIAN)
    tSmallUInt i;
    for(i=0; i<laneCount; i++)
        ((tKeccakLane*)output)[i] = ((tKeccakLane*)input)[i] ^ ((const tKeccakLane*)state)[i];
#else
    tSmallUInt i, j;
    for(i=0; i<laneCount; i++)
    {
        for(j=0; j<(64/8); j++)
        {
            output[(i*8)+j] = input[(i*8)+j] ^ ((((const tKeccakLane*)state)[i] >> (8*j)) & 0xFF);
        }
    }
#endif
}

/* ---------------------------------------------------------------- */

void KeccakP1600_ExtractAndAddBytes(const void *state, const unsigned char *input, unsigned char *output, unsigned int offset, unsigned int length)
{
    SnP_ExtractAndAddBytes(state, input, output, offset, length, KeccakP1600_ExtractAndAddLanes, KeccakP1600_ExtractAndAddBytesInLane, 8);
}

/* ---------------------------------------------------------------- */