Momentum-Apps/flipbip/lib/crypto/sha3.c

/* sha3.c - an implementation of Secure Hash Algorithm 3 (Keccak).
 * based on the
 * The Keccak SHA-3 submission. Submission to NIST (Round 3), 2011
 * by Guido Bertoni, Joan Daemen, Michaël Peeters and Gilles Van Assche
 *
 * Copyright: 2013 Aleksey Kravchenko <rhash.admin@gmail.com>
 *
 * Permission is hereby granted,  free of charge,  to any person  obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction,  including without limitation
 * the rights to  use, copy, modify,  merge, publish, distribute, sublicense,
 * and/or sell copies  of  the Software,  and to permit  persons  to whom the
 * Software is furnished to do so.
 *
 * This program  is  distributed  in  the  hope  that it will be useful,  but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  Use this program  at  your own risk!
 */

#include <assert.h>
#include <string.h>

#include "sha3.h"
#include "memzero.h"
#include "byte_order.h"

#define I64(x) x##LL
#define ROTL64(qword, n) ((qword) << (n) ^ ((qword) >> (64 - (n))))
#define le2me_64(x) (x)
#define IS_ALIGNED_64(p) (0 == (((uintptr_t)(const void*)(p)&0x7)))
#define me64_to_le_str(to, from, length) memcpy((to), (from), (length))

/* constants */
#define NumberOfRounds 24

/* SHA3 (Keccak) constants for 24 rounds */
static uint64_t keccak_round_constants[NumberOfRounds] = {
    I64(0x0000000000000001), I64(0x0000000000008082), I64(0x800000000000808A),
    I64(0x8000000080008000), I64(0x000000000000808B), I64(0x0000000080000001),
    I64(0x8000000080008081), I64(0x8000000000008009), I64(0x000000000000008A),
    I64(0x0000000000000088), I64(0x0000000080008009), I64(0x000000008000000A),
    I64(0x000000008000808B), I64(0x800000000000008B), I64(0x8000000000008089),
    I64(0x8000000000008003), I64(0x8000000000008002), I64(0x8000000000000080),
    I64(0x000000000000800A), I64(0x800000008000000A), I64(0x8000000080008081),
    I64(0x8000000000008080), I64(0x0000000080000001), I64(0x8000000080008008)};

/* Initializing a sha3 context for given number of output bits */
static void keccak_Init(SHA3_CTX* ctx, unsigned bits) {
    /* NB: The Keccak capacity parameter = bits * 2 */
    unsigned rate = 1600 - bits * 2;

    memzero(ctx, sizeof(SHA3_CTX));
    ctx->block_size = rate / 8;
    assert(rate <= 1600 && (rate % 64) == 0);
}

/**
 * Initialize context before calculating hash.
 *
 * @param ctx context to initialize
 */
void sha3_224_Init(SHA3_CTX* ctx) {
    keccak_Init(ctx, 224);
}

/**
 * Initialize context before calculating hash.
 *
 * @param ctx context to initialize
 */
void sha3_256_Init(SHA3_CTX* ctx) {
    keccak_Init(ctx, 256);
}

/**
 * Initialize context before calculating hash.
 *
 * @param ctx context to initialize
 */
void sha3_384_Init(SHA3_CTX* ctx) {
    keccak_Init(ctx, 384);
}

/**
 * Initialize context before calculating hash.
 *
 * @param ctx context to initialize
 */
void sha3_512_Init(SHA3_CTX* ctx) {
    keccak_Init(ctx, 512);
}

/* Keccak theta() transformation */
static void keccak_theta(uint64_t* A) {
    unsigned int x = 0;
    uint64_t C[5] = {0}, D[5] = {0};

    for(x = 0; x < 5; x++) {
        C[x] = A[x] ^ A[x + 5] ^ A[x + 10] ^ A[x + 15] ^ A[x + 20];
    }
    D[0] = ROTL64(C[1], 1) ^ C[4];
    D[1] = ROTL64(C[2], 1) ^ C[0];
    D[2] = ROTL64(C[3], 1) ^ C[1];
    D[3] = ROTL64(C[4], 1) ^ C[2];
    D[4] = ROTL64(C[0], 1) ^ C[3];

    for(x = 0; x < 5; x++) {
        A[x] ^= D[x];
        A[x + 5] ^= D[x];
        A[x + 10] ^= D[x];
        A[x + 15] ^= D[x];
        A[x + 20] ^= D[x];
    }
}

/* Keccak pi() transformation */
static void keccak_pi(uint64_t* A) {
    uint64_t A1 = 0;
    A1 = A[1];
    A[1] = A[6];
    A[6] = A[9];
    A[9] = A[22];
    A[22] = A[14];
    A[14] = A[20];
    A[20] = A[2];
    A[2] = A[12];
    A[12] = A[13];
    A[13] = A[19];
    A[19] = A[23];
    A[23] = A[15];
    A[15] = A[4];
    A[4] = A[24];
    A[24] = A[21];
    A[21] = A[8];
    A[8] = A[16];
    A[16] = A[5];
    A[5] = A[3];
    A[3] = A[18];
    A[18] = A[17];
    A[17] = A[11];
    A[11] = A[7];
    A[7] = A[10];
    A[10] = A1;
    /* note: A[ 0] is left as is */
}

/* Keccak chi() transformation */
static void keccak_chi(uint64_t* A) {
    int i = 0;
    for(i = 0; i < 25; i += 5) {
        uint64_t A0 = A[0 + i], A1 = A[1 + i];
        A[0 + i] ^= ~A1 & A[2 + i];
        A[1 + i] ^= ~A[2 + i] & A[3 + i];
        A[2 + i] ^= ~A[3 + i] & A[4 + i];
        A[3 + i] ^= ~A[4 + i] & A0;
        A[4 + i] ^= ~A0 & A1;
    }
}

static void sha3_permutation(uint64_t* state) {
#if BYTE_ORDER == BIG_ENDIAN
    int i;
    for(i = 0; i < 25; i++) {
        REVERSE64(state[i], state[i]);
    }
#endif
    int round = 0;
    for(round = 0; round < NumberOfRounds; round++) {
        keccak_theta(state);

        /* apply Keccak rho() transformation */
        state[1] = ROTL64(state[1], 1);
        state[2] = ROTL64(state[2], 62);
        state[3] = ROTL64(state[3], 28);
        state[4] = ROTL64(state[4], 27);
        state[5] = ROTL64(state[5], 36);
        state[6] = ROTL64(state[6], 44);
        state[7] = ROTL64(state[7], 6);
        state[8] = ROTL64(state[8], 55);
        state[9] = ROTL64(state[9], 20);
        state[10] = ROTL64(state[10], 3);
        state[11] = ROTL64(state[11], 10);
        state[12] = ROTL64(state[12], 43);
        state[13] = ROTL64(state[13], 25);
        state[14] = ROTL64(state[14], 39);
        state[15] = ROTL64(state[15], 41);
        state[16] = ROTL64(state[16], 45);
        state[17] = ROTL64(state[17], 15);
        state[18] = ROTL64(state[18], 21);
        state[19] = ROTL64(state[19], 8);
        state[20] = ROTL64(state[20], 18);
        state[21] = ROTL64(state[21], 2);
        state[22] = ROTL64(state[22], 61);
        state[23] = ROTL64(state[23], 56);
        state[24] = ROTL64(state[24], 14);

        keccak_pi(state);
        keccak_chi(state);

        /* apply iota(state, round) */
        *state ^= keccak_round_constants[round];
    }
#if BYTE_ORDER == BIG_ENDIAN
    for(i = 0; i < 25; i++) {
        REVERSE64(state[i], state[i]);
    }
#endif
}

/**
 * The core transformation. Process the specified block of data.
 *
 * @param hash the algorithm state
 * @param block the message block to process
 * @param block_size the size of the processed block in bytes
 */
static void sha3_process_block(uint64_t hash[25], const uint64_t* block, size_t block_size) {
    /* expanded loop */
    hash[0] ^= le2me_64(block[0]);
    hash[1] ^= le2me_64(block[1]);
    hash[2] ^= le2me_64(block[2]);
    hash[3] ^= le2me_64(block[3]);
    hash[4] ^= le2me_64(block[4]);
    hash[5] ^= le2me_64(block[5]);
    hash[6] ^= le2me_64(block[6]);
    hash[7] ^= le2me_64(block[7]);
    hash[8] ^= le2me_64(block[8]);
    /* if not sha3-512 */
    if(block_size > 72) {
        hash[9] ^= le2me_64(block[9]);
        hash[10] ^= le2me_64(block[10]);
        hash[11] ^= le2me_64(block[11]);
        hash[12] ^= le2me_64(block[12]);
        /* if not sha3-384 */
        if(block_size > 104) {
            hash[13] ^= le2me_64(block[13]);
            hash[14] ^= le2me_64(block[14]);
            hash[15] ^= le2me_64(block[15]);
            hash[16] ^= le2me_64(block[16]);
            /* if not sha3-256 */
            if(block_size > 136) {
                hash[17] ^= le2me_64(block[17]);
#ifdef FULL_SHA3_FAMILY_SUPPORT
                /* if not sha3-224 */
                if(block_size > 144) {
                    hash[18] ^= le2me_64(block[18]);
                    hash[19] ^= le2me_64(block[19]);
                    hash[20] ^= le2me_64(block[20]);
                    hash[21] ^= le2me_64(block[21]);
                    hash[22] ^= le2me_64(block[22]);
                    hash[23] ^= le2me_64(block[23]);
                    hash[24] ^= le2me_64(block[24]);
                }
#endif
            }
        }
    }
    /* make a permutation of the hash */
    sha3_permutation(hash);
}

#define SHA3_FINALIZED 0x80000000

/**
 * Calculate message hash.
 * Can be called repeatedly with chunks of the message to be hashed.
 *
 * @param ctx the algorithm context containing current hashing state
 * @param msg message chunk
 * @param size length of the message chunk
 */
void sha3_Update(SHA3_CTX* ctx, const unsigned char* msg, size_t size) {
    if(size == 0) return;

    size_t idx = (size_t)ctx->rest;
    size_t block_size = (size_t)ctx->block_size;

    if(ctx->rest & SHA3_FINALIZED) return; /* too late for additional input */
    ctx->rest = (unsigned)((ctx->rest + size) % block_size);

    /* fill partial block */
    if(idx) {
        size_t left = block_size - idx;
        memcpy((char*)ctx->message + idx, msg, (size < left ? size : left));
        if(size < left) return;

        /* process partial block */
        sha3_process_block(ctx->hash, ctx->message, block_size);
        msg += left;
        size -= left;
    }
    while(size >= block_size) {
        uint64_t* aligned_message_block = NULL;
        if(IS_ALIGNED_64(msg)) {
            /* the most common case is processing of an already aligned message
			without copying it */
            aligned_message_block = (uint64_t*)(void*)msg;
        } else {
            memcpy(ctx->message, msg, block_size);
            aligned_message_block = ctx->message;
        }

        sha3_process_block(ctx->hash, aligned_message_block, block_size);
        msg += block_size;
        size -= block_size;
    }
    if(size) {
        memcpy(ctx->message, msg, size); /* save leftovers */
    }
}

/**
 * Store calculated hash into the given array.
 *
 * @param ctx the algorithm context containing current hashing state
 * @param result calculated hash in binary form
 */
void sha3_Final(SHA3_CTX* ctx, unsigned char* result) {
    size_t digest_length = 100 - ctx->block_size / 2;
    const size_t block_size = ctx->block_size;

    if(!(ctx->rest & SHA3_FINALIZED)) {
        /* clear the rest of the data queue */
        memzero((char*)ctx->message + ctx->rest, block_size - ctx->rest);
        ((char*)ctx->message)[ctx->rest] |= 0x06;
        ((char*)ctx->message)[block_size - 1] |= 0x80;

        /* process final block */
        sha3_process_block(ctx->hash, ctx->message, block_size);
        ctx->rest = SHA3_FINALIZED; /* mark context as finalized */
    }

    assert(block_size > digest_length);
    if(result) me64_to_le_str(result, ctx->hash, digest_length);
    memzero(ctx, sizeof(SHA3_CTX));
}

#if USE_KECCAK
/**
* Store calculated hash into the given array.
*
* @param ctx the algorithm context containing current hashing state
* @param result calculated hash in binary form
*/
void keccak_Final(SHA3_CTX* ctx, unsigned char* result) {
    size_t digest_length = 100 - ctx->block_size / 2;
    const size_t block_size = ctx->block_size;

    if(!(ctx->rest & SHA3_FINALIZED)) {
        /* clear the rest of the data queue */
        memzero((char*)ctx->message + ctx->rest, block_size - ctx->rest);
        ((char*)ctx->message)[ctx->rest] |= 0x01;
        ((char*)ctx->message)[block_size - 1] |= 0x80;

        /* process final block */
        sha3_process_block(ctx->hash, ctx->message, block_size);
        ctx->rest = SHA3_FINALIZED; /* mark context as finalized */
    }

    assert(block_size > digest_length);
    if(result) me64_to_le_str(result, ctx->hash, digest_length);
    memzero(ctx, sizeof(SHA3_CTX));
}

void keccak_256(const unsigned char* data, size_t len, unsigned char* digest) {
    SHA3_CTX ctx = {0};
    keccak_256_Init(&ctx);
    keccak_Update(&ctx, data, len);
    keccak_Final(&ctx, digest);
}

void keccak_512(const unsigned char* data, size_t len, unsigned char* digest) {
    SHA3_CTX ctx = {0};
    keccak_512_Init(&ctx);
    keccak_Update(&ctx, data, len);
    keccak_Final(&ctx, digest);
}
#endif /* USE_KECCAK */

void sha3_256(const unsigned char* data, size_t len, unsigned char* digest) {
    SHA3_CTX ctx = {0};
    sha3_256_Init(&ctx);
    sha3_Update(&ctx, data, len);
    sha3_Final(&ctx, digest);
}

void sha3_512(const unsigned char* data, size_t len, unsigned char* digest) {
    SHA3_CTX ctx = {0};
    sha3_512_Init(&ctx);
    sha3_Update(&ctx, data, len);
    sha3_Final(&ctx, digest);
}