dogecoin/src/hash_impl.h

/**********************************************************************
 * Copyright (c) 2014 Pieter Wuille                                   *
 * Distributed under the MIT software license, see the accompanying   *
 * file COPYING or http://www.opensource.org/licenses/mit-license.php.*
 **********************************************************************/

#ifndef _SECP256K1_HASH_IMPL_H_
#define _SECP256K1_HASH_IMPL_H_

#include "hash.h"

#include <stdlib.h>
#include <stdint.h>

#define Ch(x,y,z) ((z) ^ ((x) & ((y) ^ (z))))
#define Maj(x,y,z) (((x) & (y)) | ((z) & ((x) | (y))))
#define Sigma0(x) (((x) >> 2 | (x) << 30) ^ ((x) >> 13 | (x) << 19) ^ ((x) >> 22 | (x) << 10))
#define Sigma1(x) (((x) >> 6 | (x) << 26) ^ ((x) >> 11 | (x) << 21) ^ ((x) >> 25 | (x) << 7))
#define sigma0(x) (((x) >> 7 | (x) << 25) ^ ((x) >> 18 | (x) << 14) ^ ((x) >> 3))
#define sigma1(x) (((x) >> 17 | (x) << 15) ^ ((x) >> 19 | (x) << 13) ^ ((x) >> 10))

#define Round(a,b,c,d,e,f,g,h,k,w) do { \
    uint32_t t1 = (h) + Sigma1(e) + Ch((e), (f), (g)) + (k) + (w); \
    uint32_t t2 = Sigma0(a) + Maj((a), (b), (c)); \
    (d) += t1; \
    (h) = t1 + t2; \
} while(0)

#define ReadBE32(p) (((uint32_t)((p)[0])) << 24 | ((uint32_t)((p)[1])) << 16 | ((uint32_t)((p)[2])) << 8 | ((uint32_t)((p)[3])))
#define WriteBE32(p, v) do { (p)[0] = (v) >> 24; (p)[1] = (v) >> 16; (p)[2] = (v) >> 8; (p)[3] = (v); } while(0)

static void secp256k1_sha256_initialize(secp256k1_sha256_t *hash) {
    hash->s[0] = 0x6a09e667ul;
    hash->s[1] = 0xbb67ae85ul;
    hash->s[2] = 0x3c6ef372ul;
    hash->s[3] = 0xa54ff53aul;
    hash->s[4] = 0x510e527ful;
    hash->s[5] = 0x9b05688cul;
    hash->s[6] = 0x1f83d9abul;
    hash->s[7] = 0x5be0cd19ul;
    hash->bytes = 0;
}

/** Perform one SHA-256 transformation, processing a 64-byte chunk. */
static void secp256k1_sha256_transform(uint32_t* s, const unsigned char* chunk) {
    uint32_t a = s[0], b = s[1], c = s[2], d = s[3], e = s[4], f = s[5], g = s[6], h = s[7];
    uint32_t w0, w1, w2, w3, w4, w5, w6, w7, w8, w9, w10, w11, w12, w13, w14, w15;

    Round(a, b, c, d, e, f, g, h, 0x428a2f98, w0 = ReadBE32(chunk + 0));
    Round(h, a, b, c, d, e, f, g, 0x71374491, w1 = ReadBE32(chunk + 4));
    Round(g, h, a, b, c, d, e, f, 0xb5c0fbcf, w2 = ReadBE32(chunk + 8));
    Round(f, g, h, a, b, c, d, e, 0xe9b5dba5, w3 = ReadBE32(chunk + 12));
    Round(e, f, g, h, a, b, c, d, 0x3956c25b, w4 = ReadBE32(chunk + 16));
    Round(d, e, f, g, h, a, b, c, 0x59f111f1, w5 = ReadBE32(chunk + 20));
    Round(c, d, e, f, g, h, a, b, 0x923f82a4, w6 = ReadBE32(chunk + 24));
    Round(b, c, d, e, f, g, h, a, 0xab1c5ed5, w7 = ReadBE32(chunk + 28));
    Round(a, b, c, d, e, f, g, h, 0xd807aa98, w8 = ReadBE32(chunk + 32));
    Round(h, a, b, c, d, e, f, g, 0x12835b01, w9 = ReadBE32(chunk + 36));
    Round(g, h, a, b, c, d, e, f, 0x243185be, w10 = ReadBE32(chunk + 40));
    Round(f, g, h, a, b, c, d, e, 0x550c7dc3, w11 = ReadBE32(chunk + 44));
    Round(e, f, g, h, a, b, c, d, 0x72be5d74, w12 = ReadBE32(chunk + 48));
    Round(d, e, f, g, h, a, b, c, 0x80deb1fe, w13 = ReadBE32(chunk + 52));
    Round(c, d, e, f, g, h, a, b, 0x9bdc06a7, w14 = ReadBE32(chunk + 56));
    Round(b, c, d, e, f, g, h, a, 0xc19bf174, w15 = ReadBE32(chunk + 60));

    Round(a, b, c, d, e, f, g, h, 0xe49b69c1, w0 += sigma1(w14) + w9 + sigma0(w1));
    Round(h, a, b, c, d, e, f, g, 0xefbe4786, w1 += sigma1(w15) + w10 + sigma0(w2));
    Round(g, h, a, b, c, d, e, f, 0x0fc19dc6, w2 += sigma1(w0) + w11 + sigma0(w3));
    Round(f, g, h, a, b, c, d, e, 0x240ca1cc, w3 += sigma1(w1) + w12 + sigma0(w4));
    Round(e, f, g, h, a, b, c, d, 0x2de92c6f, w4 += sigma1(w2) + w13 + sigma0(w5));
    Round(d, e, f, g, h, a, b, c, 0x4a7484aa, w5 += sigma1(w3) + w14 + sigma0(w6));
    Round(c, d, e, f, g, h, a, b, 0x5cb0a9dc, w6 += sigma1(w4) + w15 + sigma0(w7));
    Round(b, c, d, e, f, g, h, a, 0x76f988da, w7 += sigma1(w5) + w0 + sigma0(w8));
    Round(a, b, c, d, e, f, g, h, 0x983e5152, w8 += sigma1(w6) + w1 + sigma0(w9));
    Round(h, a, b, c, d, e, f, g, 0xa831c66d, w9 += sigma1(w7) + w2 + sigma0(w10));
    Round(g, h, a, b, c, d, e, f, 0xb00327c8, w10 += sigma1(w8) + w3 + sigma0(w11));
    Round(f, g, h, a, b, c, d, e, 0xbf597fc7, w11 += sigma1(w9) + w4 + sigma0(w12));
    Round(e, f, g, h, a, b, c, d, 0xc6e00bf3, w12 += sigma1(w10) + w5 + sigma0(w13));
    Round(d, e, f, g, h, a, b, c, 0xd5a79147, w13 += sigma1(w11) + w6 + sigma0(w14));
    Round(c, d, e, f, g, h, a, b, 0x06ca6351, w14 += sigma1(w12) + w7 + sigma0(w15));
    Round(b, c, d, e, f, g, h, a, 0x14292967, w15 += sigma1(w13) + w8 + sigma0(w0));

    Round(a, b, c, d, e, f, g, h, 0x27b70a85, w0 += sigma1(w14) + w9 + sigma0(w1));
    Round(h, a, b, c, d, e, f, g, 0x2e1b2138, w1 += sigma1(w15) + w10 + sigma0(w2));
    Round(g, h, a, b, c, d, e, f, 0x4d2c6dfc, w2 += sigma1(w0) + w11 + sigma0(w3));
    Round(f, g, h, a, b, c, d, e, 0x53380d13, w3 += sigma1(w1) + w12 + sigma0(w4));
    Round(e, f, g, h, a, b, c, d, 0x650a7354, w4 += sigma1(w2) + w13 + sigma0(w5));
    Round(d, e, f, g, h, a, b, c, 0x766a0abb, w5 += sigma1(w3) + w14 + sigma0(w6));
    Round(c, d, e, f, g, h, a, b, 0x81c2c92e, w6 += sigma1(w4) + w15 + sigma0(w7));
    Round(b, c, d, e, f, g, h, a, 0x92722c85, w7 += sigma1(w5) + w0 + sigma0(w8));
    Round(a, b, c, d, e, f, g, h, 0xa2bfe8a1, w8 += sigma1(w6) + w1 + sigma0(w9));
    Round(h, a, b, c, d, e, f, g, 0xa81a664b, w9 += sigma1(w7) + w2 + sigma0(w10));
    Round(g, h, a, b, c, d, e, f, 0xc24b8b70, w10 += sigma1(w8) + w3 + sigma0(w11));
    Round(f, g, h, a, b, c, d, e, 0xc76c51a3, w11 += sigma1(w9) + w4 + sigma0(w12));
    Round(e, f, g, h, a, b, c, d, 0xd192e819, w12 += sigma1(w10) + w5 + sigma0(w13));
    Round(d, e, f, g, h, a, b, c, 0xd6990624, w13 += sigma1(w11) + w6 + sigma0(w14));
    Round(c, d, e, f, g, h, a, b, 0xf40e3585, w14 += sigma1(w12) + w7 + sigma0(w15));
    Round(b, c, d, e, f, g, h, a, 0x106aa070, w15 += sigma1(w13) + w8 + sigma0(w0));

    Round(a, b, c, d, e, f, g, h, 0x19a4c116, w0 += sigma1(w14) + w9 + sigma0(w1));
    Round(h, a, b, c, d, e, f, g, 0x1e376c08, w1 += sigma1(w15) + w10 + sigma0(w2));
    Round(g, h, a, b, c, d, e, f, 0x2748774c, w2 += sigma1(w0) + w11 + sigma0(w3));
    Round(f, g, h, a, b, c, d, e, 0x34b0bcb5, w3 += sigma1(w1) + w12 + sigma0(w4));
    Round(e, f, g, h, a, b, c, d, 0x391c0cb3, w4 += sigma1(w2) + w13 + sigma0(w5));
    Round(d, e, f, g, h, a, b, c, 0x4ed8aa4a, w5 += sigma1(w3) + w14 + sigma0(w6));
    Round(c, d, e, f, g, h, a, b, 0x5b9cca4f, w6 += sigma1(w4) + w15 + sigma0(w7));
    Round(b, c, d, e, f, g, h, a, 0x682e6ff3, w7 += sigma1(w5) + w0 + sigma0(w8));
    Round(a, b, c, d, e, f, g, h, 0x748f82ee, w8 += sigma1(w6) + w1 + sigma0(w9));
    Round(h, a, b, c, d, e, f, g, 0x78a5636f, w9 += sigma1(w7) + w2 + sigma0(w10));
    Round(g, h, a, b, c, d, e, f, 0x84c87814, w10 += sigma1(w8) + w3 + sigma0(w11));
    Round(f, g, h, a, b, c, d, e, 0x8cc70208, w11 += sigma1(w9) + w4 + sigma0(w12));
    Round(e, f, g, h, a, b, c, d, 0x90befffa, w12 += sigma1(w10) + w5 + sigma0(w13));
    Round(d, e, f, g, h, a, b, c, 0xa4506ceb, w13 += sigma1(w11) + w6 + sigma0(w14));
    Round(c, d, e, f, g, h, a, b, 0xbef9a3f7, w14 + sigma1(w12) + w7 + sigma0(w15));
    Round(b, c, d, e, f, g, h, a, 0xc67178f2, w15 + sigma1(w13) + w8 + sigma0(w0));

    s[0] += a;
    s[1] += b;
    s[2] += c;
    s[3] += d;
    s[4] += e;
    s[5] += f;
    s[6] += g;
    s[7] += h;
}

static void secp256k1_sha256_write(secp256k1_sha256_t *hash, const unsigned char *data, size_t len) {
    const unsigned char* end = data + len;
    size_t bufsize = hash->bytes % 64;
    if (bufsize && bufsize + len >= 64) {
        // Fill the buffer, and process it.
        memcpy(hash->buf + bufsize, data, 64 - bufsize);
        hash->bytes += 64 - bufsize;
        data += 64 - bufsize;
        secp256k1_sha256_transform(hash->s, hash->buf);
        bufsize = 0;
    }
    while (end >= data + 64) {
        // Process full chunks directly from the source.
        secp256k1_sha256_transform(hash->s, data);
        hash->bytes += 64;
        data += 64;
    }
    if (end > data) {
        // Fill the buffer with what remains.
        memcpy(hash->buf + bufsize, data, end - data);
        hash->bytes += end - data;
    }
}

static void secp256k1_sha256_finalize(secp256k1_sha256_t *hash, unsigned char *out32) {
    static const unsigned char pad[64] = {0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
    unsigned char sizedesc[8];
    WriteBE32(sizedesc, hash->bytes >> 29);
    WriteBE32(sizedesc + 4, hash->bytes << 3);
    secp256k1_sha256_write(hash, pad, 1 + ((119 - (hash->bytes % 64)) % 64));
    secp256k1_sha256_write(hash, sizedesc, 8);
    WriteBE32(out32, hash->s[0]);
    hash->s[0] = 0;
    WriteBE32(out32 + 4, hash->s[1]);
    hash->s[1] = 0;
    WriteBE32(out32 + 8, hash->s[2]);
    hash->s[2] = 0;
    WriteBE32(out32 + 12, hash->s[3]);
    hash->s[3] = 0;
    WriteBE32(out32 + 16, hash->s[4]);
    hash->s[4] = 0;
    WriteBE32(out32 + 20, hash->s[5]);
    hash->s[5] = 0;
    WriteBE32(out32 + 24, hash->s[6]);
    hash->s[6] = 0;
    WriteBE32(out32 + 28, hash->s[7]);
    hash->s[7] = 0;
}

static void secp256k1_hmac_sha256_initialize(secp256k1_hmac_sha256_t *hash, const unsigned char *key, size_t keylen) {
    unsigned char rkey[64];
    if (keylen <= 64) {
        memcpy(rkey, key, keylen);
        memset(rkey + keylen, 0, 64 - keylen);
    } else {
        secp256k1_sha256_t sha256;
        secp256k1_sha256_initialize(&sha256);
        secp256k1_sha256_write(&sha256, key, keylen);
        secp256k1_sha256_finalize(&sha256, rkey);
        memset(rkey + 32, 0, 32);
    }

    secp256k1_sha256_initialize(&hash->outer);
    for (int n = 0; n < 64; n++)
        rkey[n] ^= 0x5c;
    secp256k1_sha256_write(&hash->outer, rkey, 64);

    secp256k1_sha256_initialize(&hash->inner);
    for (int n = 0; n < 64; n++)
        rkey[n] ^= 0x5c ^ 0x36;
    secp256k1_sha256_write(&hash->inner, rkey, 64);
    memset(rkey, 0, 64);
}

static void secp256k1_hmac_sha256_write(secp256k1_hmac_sha256_t *hash, const unsigned char *data, size_t size) {
    secp256k1_sha256_write(&hash->inner, data, size);
}

static void secp256k1_hmac_sha256_finalize(secp256k1_hmac_sha256_t *hash, unsigned char *out32) {
    unsigned char temp[32];
    secp256k1_sha256_finalize(&hash->inner, temp);
    secp256k1_sha256_write(&hash->outer, temp, 32);
    memset(temp, 0, 32);
    secp256k1_sha256_finalize(&hash->outer, out32);
}


static void secp256k1_rfc6979_hmac_sha256_initialize(secp256k1_rfc6979_hmac_sha256_t *rng, const unsigned char *key, size_t keylen, const unsigned char *msg, size_t msglen) {
    static const unsigned char zero[1] = {0x00};
    static const unsigned char one[1] = {0x01};

    memset(rng->v, 0x01, 32);
    memset(rng->k, 0x00, 32);

    secp256k1_hmac_sha256_t hmac;
    secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
    secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
    secp256k1_hmac_sha256_write(&hmac, zero, 1);
    secp256k1_hmac_sha256_write(&hmac, key, keylen);
    secp256k1_hmac_sha256_write(&hmac, msg, msglen);
    secp256k1_hmac_sha256_finalize(&hmac, rng->k);
    secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
    secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
    secp256k1_hmac_sha256_finalize(&hmac, rng->v);

    secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
    secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
    secp256k1_hmac_sha256_write(&hmac, one, 1);
    secp256k1_hmac_sha256_write(&hmac, key, keylen);
    secp256k1_hmac_sha256_write(&hmac, msg, msglen);
    secp256k1_hmac_sha256_finalize(&hmac, rng->k);
    secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
    secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
    secp256k1_hmac_sha256_finalize(&hmac, rng->v);
    rng->retry = 0;
}

static void secp256k1_rfc6979_hmac_sha256_generate(secp256k1_rfc6979_hmac_sha256_t *rng, unsigned char *out, size_t outlen) {
    static const unsigned char zero[1] = {0x00};
    if (rng->retry) {
        secp256k1_hmac_sha256_t hmac;
        secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
        secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
        secp256k1_hmac_sha256_write(&hmac, zero, 1);
        secp256k1_hmac_sha256_finalize(&hmac, rng->k);
        secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
        secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
        secp256k1_hmac_sha256_finalize(&hmac, rng->v);
    }

    while (outlen > 0) {
        secp256k1_hmac_sha256_t hmac;
        secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
        secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
        secp256k1_hmac_sha256_finalize(&hmac, rng->v);
        int now = outlen;
        if (now > 32) {
            now = 32;
        }
        memcpy(out, rng->v, now);
        out += now;
        outlen -= now;
    }

    rng->retry = 1;
}

static void secp256k1_rfc6979_hmac_sha256_finalize(secp256k1_rfc6979_hmac_sha256_t *rng) {
    memset(rng->k, 0, 32);
    memset(rng->v, 0, 32);
    rng->retry = 0;
}


#undef Round
#undef sigma0
#undef sigma1
#undef Sigma0
#undef Sigma1
#undef Ch
#undef Maj
#undef ReadBE32
#undef WriteBE32

#endif