File content as of revision 0:7a1237bd2d13:

#include "SHA2_64.h"
#include <string.h>


static const uint64_t K[] =
{
   0x428a2f98d728ae22, 0x7137449123ef65cd, 0xb5c0fbcfec4d3b2f, 0xe9b5dba58189dbbc,
   0x3956c25bf348b538, 0x59f111f1b605d019, 0x923f82a4af194f9b, 0xab1c5ed5da6d8118,
   0xd807aa98a3030242, 0x12835b0145706fbe, 0x243185be4ee4b28c, 0x550c7dc3d5ffb4e2,
   0x72be5d74f27b896f, 0x80deb1fe3b1696b1, 0x9bdc06a725c71235, 0xc19bf174cf692694,
   0xe49b69c19ef14ad2, 0xefbe4786384f25e3, 0x0fc19dc68b8cd5b5, 0x240ca1cc77ac9c65,
   0x2de92c6f592b0275, 0x4a7484aa6ea6e483, 0x5cb0a9dcbd41fbd4, 0x76f988da831153b5,
   0x983e5152ee66dfab, 0xa831c66d2db43210, 0xb00327c898fb213f, 0xbf597fc7beef0ee4,
   0xc6e00bf33da88fc2, 0xd5a79147930aa725, 0x06ca6351e003826f, 0x142929670a0e6e70,
   0x27b70a8546d22ffc, 0x2e1b21385c26c926, 0x4d2c6dfc5ac42aed, 0x53380d139d95b3df,
   0x650a73548baf63de, 0x766a0abb3c77b2a8, 0x81c2c92e47edaee6, 0x92722c851482353b,
   0xa2bfe8a14cf10364, 0xa81a664bbc423001, 0xc24b8b70d0f89791, 0xc76c51a30654be30,
   0xd192e819d6ef5218, 0xd69906245565a910, 0xf40e35855771202a, 0x106aa07032bbd1b8,
   0x19a4c116b8d2d0c8, 0x1e376c085141ab53, 0x2748774cdf8eeb99, 0x34b0bcb5e19b48a8,
   0x391c0cb3c5c95a63, 0x4ed8aa4ae3418acb, 0x5b9cca4f7763e373, 0x682e6ff3d6b2b8a3,
   0x748f82ee5defb2fc, 0x78a5636f43172f60, 0x84c87814a1f0ab72, 0x8cc702081a6439ec,
   0x90befffa23631e28, 0xa4506cebde82bde9, 0xbef9a3f7b2c67915, 0xc67178f2e372532b,
   0xca273eceea26619c, 0xd186b8c721c0c207, 0xeada7dd6cde0eb1e, 0xf57d4f7fee6ed178,
   0x06f067aa72176fba, 0x0a637dc5a2c898a6, 0x113f9804bef90dae, 0x1b710b35131c471b,
   0x28db77f523047d84, 0x32caab7b40c72493, 0x3c9ebe0a15c9bebc, 0x431d67c49c100d4c,
   0x4cc5d4becb3e42b6, 0x597f299cfc657e2a, 0x5fcb6fab3ad6faec, 0x6c44198c4a475817
};

static const uint64_t H[] =
{
    // SHA-384
    0xcbbb9d5dc1059ed8, 0x629a292a367cd507, 0x9159015a3070dd17, 0x152fecd8f70e5939,
    0x67332667ffc00b31, 0x8eb44a8768581511, 0xdb0c2e0d64f98fa7, 0x47b5481dbefa4fa4,

    // SHA-512
    0x6a09e667f3bcc908, 0xbb67ae8584caa73b, 0x3c6ef372fe94f82b, 0xa54ff53a5f1d36f1,
    0x510e527fade682d1, 0x9b05688c2b3e6c1f, 0x1f83d9abfb41bd6b, 0x5be0cd19137e2179
};

static uint64_t revWord(uint64_t w)
{
    uint8_t buffer[8];
    buffer[0] = w >> 56;
    buffer[1] = w >> 48;
    buffer[2] = w >> 40;
    buffer[3] = w >> 32;
    buffer[4] = w >> 24;
    buffer[5] = w >> 16;
    buffer[6] = w >> 8;
    buffer[7] = w;
    
    uint64_t res = buffer[7];
    res <<= 8;
    res |= buffer[6];
    res <<= 8;
    res |= buffer[5];
    res <<= 8;
    res |= buffer[4];
    res <<= 8;
    res |= buffer[3];
    res <<= 8;
    res |= buffer[2];
    res <<= 8;
    res |= buffer[1];
    res <<= 8;
    res |= buffer[0];

    return res;
}
    
static uint64_t rotLeft(uint64_t w, uint8_t n)
{
    return (w << n) | (w >> (64-n));
}

static uint64_t rotRight(uint64_t w, uint8_t n)
{
    return rotLeft(w,64-n);
}

static uint64_t CH(uint64_t x, uint64_t y, uint64_t z)
{
    return (x & y) ^ ((~x) & z);
}

static uint64_t MAJ(uint64_t x, uint64_t y, uint64_t z)
{
    return (x & y) ^ (x & z) ^ (y & z);
}

static uint64_t BSIG0(uint64_t x)
{
    return rotRight(x,28) ^ rotRight(x,34) ^ rotRight(x,39);
}

static uint64_t BSIG1(uint64_t x)
{
    return rotRight(x,14) ^ rotRight(x,18) ^ rotRight(x,41);
}

static uint64_t SSIG0(uint64_t x)
{
    return rotRight(x,1) ^ rotRight(x,8) ^ (x >> 7);
}

static uint64_t SSIG1(uint64_t x)
{
    return rotRight(x,19) ^ rotRight(x,61) ^ (x>>6);
}

SHA2_64::SHA2_64(SHA2_64_TYPE t):
type(t),
totalBufferLength(0),
bufferLength(0)
{
    switch(type)
    {
        case SHA_384:
            h0 = H[0];
            h1 = H[1];
            h2 = H[2];
            h3 = H[3];
            h4 = H[4];
            h5 = H[5];
            h6 = H[6];
            h7 = H[7];
        break;
        
        case SHA_512:
            h0 = H[8];
            h1 = H[9];
            h2 = H[10];
            h3 = H[11];
            h4 = H[12];
            h5 = H[13];
            h6 = H[14];
            h7 = H[15];     
        break;
    }
}

void SHA2_64::add(uint8_t *in, uint32_t length)
{
    if(length < 128-bufferLength)
    {
        memcpy(&buffer[bufferLength], in, length);
        bufferLength += length;
        totalBufferLength += length;
        return;
    }
    int offset = 128-bufferLength;
    memcpy(&buffer[bufferLength], in, offset);
    computeBlock(&h0,&h1,&h2,&h3,&h4,&h5,&h6,&h7,buffer);
    while(length-offset > 128)
    {
        memcpy(buffer, &in[offset], 128);
        computeBlock(&h0,&h1,&h2,&h3,&h4,&h5,&h6,&h7,buffer);
        offset += 128;
    }
    if(offset > length)
        offset -= 128;
    bufferLength = length - offset;
    memcpy(buffer, &in[offset], bufferLength);
    totalBufferLength += length;
}

void SHA2_64::computeDigest(uint8_t *digest)
{
    uint16_t padding;
    if(totalBufferLength % 128 < 112)
        padding = 112 - (totalBufferLength % 128);
    else
        padding = 112 + (128 - (totalBufferLength % 128));
    uint8_t val = 0x80;
    add(&val, 1);
    val = 0;
    for(int i = 0; i < padding-1; ++i)
        add(&val,1);
    totalBufferLength -= padding;
    uint64_t lengthBit = 0;
    add((uint8_t*)&lengthBit, 8);
    lengthBit = (totalBufferLength - 8) * 8;
    lengthBit = revWord(lengthBit);
    add((uint8_t*)&lengthBit, 8);

    h0 = revWord(h0);
    h1 = revWord(h1);
    h2 = revWord(h2);
    h3 = revWord(h3);
    h4 = revWord(h4);
    h5 = revWord(h5);

    
    memcpy(digest, &h0, 8);
    memcpy(&digest[8], &h1, 8);
    memcpy(&digest[16], &h2, 8);
    memcpy(&digest[24], &h3, 8);
    memcpy(&digest[32], &h4, 8);
    memcpy(&digest[40], &h5, 8);

    if(type == SHA_512)
    {
        h6 = revWord(h6);
        h7 = revWord(h7);
        memcpy(&digest[48], &h6, 8);
        memcpy(&digest[56], &h7, 8);
    }
    
    // reset state
    switch(type)
    {
        case SHA_384:
            h0 = H[0];
            h1 = H[1];
            h2 = H[2];
            h3 = H[3];
            h4 = H[4];
            h5 = H[5];
            h6 = H[6];
            h7 = H[7];
        break;
        
        case SHA_512:
            h0 = H[8];
            h1 = H[9];
            h2 = H[10];
            h3 = H[11];
            h4 = H[12];
            h5 = H[13];
            h6 = H[14];
            h7 = H[15];     
        break;
    }
    totalBufferLength = 0;
    bufferLength = 0;
}

void SHA2_64::computeBlock(uint64_t *h02, 
                     uint64_t *h12, 
                     uint64_t *h22, 
                     uint64_t *h32, 
                     uint64_t *h42, 
                     uint64_t *h52, 
                     uint64_t *h62,
                     uint64_t *h72,
                     uint8_t *buffer)
{
    uint64_t w[80];
    for(int t = 0; t < 16; ++t) 
    {
        memcpy(&w[t], &buffer[t*8], 8);
        w[t] = revWord(w[t]);
    }
    for(int t = 16; t < 80; ++t)
        w[t] = SSIG1(w[t-2]) + w[t-7] + SSIG0(w[t-15]) + w[t-16];
    
    uint64_t a = *h02, b = *h12, c = *h22, d = *h32, e = *h42, f = *h52, g = *h62, h = *h72;
    for(int t = 0; t < 80; ++t)
    {
        uint64_t T1 = h + BSIG1(e) + CH(e,f,g) + K[t] + w[t];
        uint64_t T2 = BSIG0(a) + MAJ(a,b,c);
        h = g;
        g = f;
        f = e;
        e = d + T1;
        d = c;
        c = b;
        b = a;
        a = T1 + T2;
    }
    *h02 += a;
    *h12 += b;
    *h22 += c;
    *h32 += d;
    *h42 += e;
    *h52 += f;
    *h62 += g;
    *h72 += h;
}

void SHA2_64::computeDigest(SHA2_64_TYPE type, uint8_t *digest, uint8_t *in, uint32_t length)
{
    uint64_t h0 = H[type*8], h1 = H[type*8+1], h2 = H[type*8+2], h3 = H[type*8+3];
    uint64_t h4 = H[type*8+4], h5 = H[type*8+5], h6 = H[type*8+6], h7 = H[type*8+7];
    int offset = 0;
    while(length - offset >= 128)
    {
        computeBlock(&h0, &h1, &h2, &h3, &h4, &h5, &h6, &h7, &in[offset]);
        offset += 128;
    }
    uint8_t bufferLength = length-offset;
    uint8_t buffer[128];
    memcpy(buffer, &in[offset],bufferLength); 
    uint16_t padding;
    if(length % 128 < 112)
        padding = 112 - (length % 128);
    else
        padding = 112 + (128 - (length % 128));
    buffer[bufferLength] = 0x80;
    bufferLength++;
    padding--;
    while(padding > 0)
    {
        if(bufferLength == 128)
        {
            computeBlock(&h0, &h1, &h2, &h3, &h4, &h5, &h6, &h7, buffer);
            bufferLength = 0;
        }
        buffer[bufferLength] = 0;
        bufferLength++;
        padding--;
    }
    uint64_t lengthBit = length * 8;
    lengthBit = revWord(lengthBit);
    memset(&buffer[112], 0, 8); 
    memcpy(&buffer[120], &lengthBit, 8);
    computeBlock(&h0, &h1, &h2, &h3, &h4, &h5, &h6, &h7, buffer);

    h0 = revWord(h0);
    h1 = revWord(h1);
    h2 = revWord(h2);
    h3 = revWord(h3);
    h4 = revWord(h4);
    h5 = revWord(h5);

    
    memcpy(digest, &h0, 8);
    memcpy(&digest[8], &h1, 8);
    memcpy(&digest[16], &h2, 8);
    memcpy(&digest[24], &h3, 8);
    memcpy(&digest[32], &h4, 8);
    memcpy(&digest[40], &h5, 8);

    if(type == SHA_512)
    {
        h6 = revWord(h6);
        h7 = revWord(h7);
        memcpy(&digest[48], &h6, 8);
        memcpy(&digest[56], &h7, 8);
    }
}