/* Based on the public domain implementation in
 * crypto_hash/sha512/ref/ from http://bench.cr.yp.to/supercop.html
 * by D. J. Bernstein */

#include "sha2.h"

typedef unsigned long long uint64;

static uint64 load_bigendian(const unsigned char *x)
{
  return
      (uint64) (x[7]) \
  | (((uint64) (x[6])) << 8) \
  | (((uint64) (x[5])) << 16) \
  | (((uint64) (x[4])) << 24) \
  | (((uint64) (x[3])) << 32) \
  | (((uint64) (x[2])) << 40) \
  | (((uint64) (x[1])) << 48) \
  | (((uint64) (x[0])) << 56)
  ;
}

static void store_bigendian(unsigned char *x,uint64 u)
{
  x[7] = u; u >>= 8;
  x[6] = u; u >>= 8;
  x[5] = u; u >>= 8;
  x[4] = u; u >>= 8;
  x[3] = u; u >>= 8;
  x[2] = u; u >>= 8;
  x[1] = u; u >>= 8;
  x[0] = u;
}

#define SHR(x,c) ((x) >> (c))
#define ROTR(x,c) (((x) >> (c)) | ((x) << (64 - (c))))

#define Ch(x,y,z) ((x & y) ^ (~x & z))
#define Maj(x,y,z) ((x & y) ^ (x & z) ^ (y & z))
#define Sigma0(x) (ROTR(x,28) ^ ROTR(x,34) ^ ROTR(x,39))
#define Sigma1(x) (ROTR(x,14) ^ ROTR(x,18) ^ ROTR(x,41))
#define sigma0(x) (ROTR(x, 1) ^ ROTR(x, 8) ^ SHR(x,7))
#define sigma1(x) (ROTR(x,19) ^ ROTR(x,61) ^ SHR(x,6))

#define M(w0,w14,w9,w1) w0 = sigma1(w14) + w9 + sigma0(w1) + w0;

#define EXPAND \
  M(w0 ,w14,w9 ,w1 ) \
  M(w1 ,w15,w10,w2 ) \
  M(w2 ,w0 ,w11,w3 ) \
  M(w3 ,w1 ,w12,w4 ) \
  M(w4 ,w2 ,w13,w5 ) \
  M(w5 ,w3 ,w14,w6 ) \
  M(w6 ,w4 ,w15,w7 ) \
  M(w7 ,w5 ,w0 ,w8 ) \
  M(w8 ,w6 ,w1 ,w9 ) \
  M(w9 ,w7 ,w2 ,w10) \
  M(w10,w8 ,w3 ,w11) \
  M(w11,w9 ,w4 ,w12) \
  M(w12,w10,w5 ,w13) \
  M(w13,w11,w6 ,w14) \
  M(w14,w12,w7 ,w15) \
  M(w15,w13,w8 ,w0 )

#define F(w,k) \
  T1 = h + Sigma1(e) + Ch(e,f,g) + k + w; \
  T2 = Sigma0(a) + Maj(a,b,c); \
  h = g; \
  g = f; \
  f = e; \
  e = d + T1; \
  d = c; \
  c = b; \
  b = a; \
  a = T1 + T2;

static int crypto_hashblocks_sha512(unsigned char *statebytes,const unsigned char *in,unsigned long long inlen)
{
  uint64 state[8];
  uint64 a;
  uint64 b;
  uint64 c;
  uint64 d;
  uint64 e;
  uint64 f;
  uint64 g;
  uint64 h;
  uint64 T1;
  uint64 T2;

  a = load_bigendian(statebytes +  0); state[0] = a;
  b = load_bigendian(statebytes +  8); state[1] = b;
  c = load_bigendian(statebytes + 16); state[2] = c;
  d = load_bigendian(statebytes + 24); state[3] = d;
  e = load_bigendian(statebytes + 32); state[4] = e;
  f = load_bigendian(statebytes + 40); state[5] = f;
  g = load_bigendian(statebytes + 48); state[6] = g;
  h = load_bigendian(statebytes + 56); state[7] = h;

  while (inlen >= 128) {
    uint64 w0  = load_bigendian(in +   0);
    uint64 w1  = load_bigendian(in +   8);
    uint64 w2  = load_bigendian(in +  16);
    uint64 w3  = load_bigendian(in +  24);
    uint64 w4  = load_bigendian(in +  32);
    uint64 w5  = load_bigendian(in +  40);
    uint64 w6  = load_bigendian(in +  48);
    uint64 w7  = load_bigendian(in +  56);
    uint64 w8  = load_bigendian(in +  64);
    uint64 w9  = load_bigendian(in +  72);
    uint64 w10 = load_bigendian(in +  80);
    uint64 w11 = load_bigendian(in +  88);
    uint64 w12 = load_bigendian(in +  96);
    uint64 w13 = load_bigendian(in + 104);
    uint64 w14 = load_bigendian(in + 112);
    uint64 w15 = load_bigendian(in + 120);

    F(w0 ,0x428a2f98d728ae22ULL)
    F(w1 ,0x7137449123ef65cdULL)
    F(w2 ,0xb5c0fbcfec4d3b2fULL)
    F(w3 ,0xe9b5dba58189dbbcULL)
    F(w4 ,0x3956c25bf348b538ULL)
    F(w5 ,0x59f111f1b605d019ULL)
    F(w6 ,0x923f82a4af194f9bULL)
    F(w7 ,0xab1c5ed5da6d8118ULL)
    F(w8 ,0xd807aa98a3030242ULL)
    F(w9 ,0x12835b0145706fbeULL)
    F(w10,0x243185be4ee4b28cULL)
    F(w11,0x550c7dc3d5ffb4e2ULL)
    F(w12,0x72be5d74f27b896fULL)
    F(w13,0x80deb1fe3b1696b1ULL)
    F(w14,0x9bdc06a725c71235ULL)
    F(w15,0xc19bf174cf692694ULL)

    EXPAND

    F(w0 ,0xe49b69c19ef14ad2ULL)
    F(w1 ,0xefbe4786384f25e3ULL)
    F(w2 ,0x0fc19dc68b8cd5b5ULL)
    F(w3 ,0x240ca1cc77ac9c65ULL)
    F(w4 ,0x2de92c6f592b0275ULL)
    F(w5 ,0x4a7484aa6ea6e483ULL)
    F(w6 ,0x5cb0a9dcbd41fbd4ULL)
    F(w7 ,0x76f988da831153b5ULL)
    F(w8 ,0x983e5152ee66dfabULL)
    F(w9 ,0xa831c66d2db43210ULL)
    F(w10,0xb00327c898fb213fULL)
    F(w11,0xbf597fc7beef0ee4ULL)
    F(w12,0xc6e00bf33da88fc2ULL)
    F(w13,0xd5a79147930aa725ULL)
    F(w14,0x06ca6351e003826fULL)
    F(w15,0x142929670a0e6e70ULL)

    EXPAND

    F(w0 ,0x27b70a8546d22ffcULL)
    F(w1 ,0x2e1b21385c26c926ULL)
    F(w2 ,0x4d2c6dfc5ac42aedULL)
    F(w3 ,0x53380d139d95b3dfULL)
    F(w4 ,0x650a73548baf63deULL)
    F(w5 ,0x766a0abb3c77b2a8ULL)
    F(w6 ,0x81c2c92e47edaee6ULL)
    F(w7 ,0x92722c851482353bULL)
    F(w8 ,0xa2bfe8a14cf10364ULL)
    F(w9 ,0xa81a664bbc423001ULL)
    F(w10,0xc24b8b70d0f89791ULL)
    F(w11,0xc76c51a30654be30ULL)
    F(w12,0xd192e819d6ef5218ULL)
    F(w13,0xd69906245565a910ULL)
    F(w14,0xf40e35855771202aULL)
    F(w15,0x106aa07032bbd1b8ULL)

    EXPAND

    F(w0 ,0x19a4c116b8d2d0c8ULL)
    F(w1 ,0x1e376c085141ab53ULL)
    F(w2 ,0x2748774cdf8eeb99ULL)
    F(w3 ,0x34b0bcb5e19b48a8ULL)
    F(w4 ,0x391c0cb3c5c95a63ULL)
    F(w5 ,0x4ed8aa4ae3418acbULL)
    F(w6 ,0x5b9cca4f7763e373ULL)
    F(w7 ,0x682e6ff3d6b2b8a3ULL)
    F(w8 ,0x748f82ee5defb2fcULL)
    F(w9 ,0x78a5636f43172f60ULL)
    F(w10,0x84c87814a1f0ab72ULL)
    F(w11,0x8cc702081a6439ecULL)
    F(w12,0x90befffa23631e28ULL)
    F(w13,0xa4506cebde82bde9ULL)
    F(w14,0xbef9a3f7b2c67915ULL)
    F(w15,0xc67178f2e372532bULL)

    EXPAND

    F(w0 ,0xca273eceea26619cULL)
    F(w1 ,0xd186b8c721c0c207ULL)
    F(w2 ,0xeada7dd6cde0eb1eULL)
    F(w3 ,0xf57d4f7fee6ed178ULL)
    F(w4 ,0x06f067aa72176fbaULL)
    F(w5 ,0x0a637dc5a2c898a6ULL)
    F(w6 ,0x113f9804bef90daeULL)
    F(w7 ,0x1b710b35131c471bULL)
    F(w8 ,0x28db77f523047d84ULL)
    F(w9 ,0x32caab7b40c72493ULL)
    F(w10,0x3c9ebe0a15c9bebcULL)
    F(w11,0x431d67c49c100d4cULL)
    F(w12,0x4cc5d4becb3e42b6ULL)
    F(w13,0x597f299cfc657e2aULL)
    F(w14,0x5fcb6fab3ad6faecULL)
    F(w15,0x6c44198c4a475817ULL)

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

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

    in += 128;
    inlen -= 128;
  }

  store_bigendian(statebytes +  0,state[0]);
  store_bigendian(statebytes +  8,state[1]);
  store_bigendian(statebytes + 16,state[2]);
  store_bigendian(statebytes + 24,state[3]);
  store_bigendian(statebytes + 32,state[4]);
  store_bigendian(statebytes + 40,state[5]);
  store_bigendian(statebytes + 48,state[6]);
  store_bigendian(statebytes + 56,state[7]);

  return inlen;
}

#define blocks crypto_hashblocks_sha512

static const unsigned char iv_384[64] = {
  0xcb,0xbb,0x9d,0x5d,0xc1,0x05,0x9e,0xd8,
  0x62,0x9a,0x29,0x2a,0x36,0x7c,0xd5,0x07,
  0x91,0x59,0x01,0x5a,0x30,0x70,0xdd,0x17,
  0x15,0x2f,0xec,0xd8,0xf7,0x0e,0x59,0x39,
  0x67,0x33,0x26,0x67,0xff,0xc0,0x0b,0x31,
  0x8e,0xb4,0x4a,0x87,0x68,0x58,0x15,0x11,
  0xdb,0x0c,0x2e,0x0d,0x64,0xf9,0x8f,0xa7,
  0x47,0xb5,0x48,0x1d,0xbe,0xfa,0x4f,0xa4
};

static const unsigned char iv_512[64] = {
  0x6a,0x09,0xe6,0x67,0xf3,0xbc,0xc9,0x08,
  0xbb,0x67,0xae,0x85,0x84,0xca,0xa7,0x3b,
  0x3c,0x6e,0xf3,0x72,0xfe,0x94,0xf8,0x2b,
  0xa5,0x4f,0xf5,0x3a,0x5f,0x1d,0x36,0xf1,
  0x51,0x0e,0x52,0x7f,0xad,0xe6,0x82,0xd1,
  0x9b,0x05,0x68,0x8c,0x2b,0x3e,0x6c,0x1f,
  0x1f,0x83,0xd9,0xab,0xfb,0x41,0xbd,0x6b,
  0x5b,0xe0,0xcd,0x19,0x13,0x7e,0x21,0x79
};

int sha384(unsigned char *out, const unsigned char *in, unsigned long long inlen)
{
  unsigned char h[64];
  unsigned char padded[256];
  unsigned int i;
  unsigned long long bytes = inlen;

  for (i = 0;i < 64;++i) h[i] = iv_384[i];

  blocks(h,in,inlen);
  in += inlen;
  inlen &= 127;
  in -= inlen;

  for (i = 0;i < inlen;++i) padded[i] = in[i];
  padded[inlen] = 0x80;

  if (inlen < 112) {
    for (i = inlen + 1;i < 119;++i) padded[i] = 0;
    padded[119] = bytes >> 61;
    padded[120] = bytes >> 53;
    padded[121] = bytes >> 45;
    padded[122] = bytes >> 37;
    padded[123] = bytes >> 29;
    padded[124] = bytes >> 21;
    padded[125] = bytes >> 13;
    padded[126] = bytes >> 5;
    padded[127] = bytes << 3;
    blocks(h,padded,128);
  } else {
    for (i = inlen + 1;i < 247;++i) padded[i] = 0;
    padded[247] = bytes >> 61;
    padded[248] = bytes >> 53;
    padded[249] = bytes >> 45;
    padded[250] = bytes >> 37;
    padded[251] = bytes >> 29;
    padded[252] = bytes >> 21;
    padded[253] = bytes >> 13;
    padded[254] = bytes >> 5;
    padded[255] = bytes << 3;
    blocks(h,padded,256);
  }

  for (i = 0;i < 48;++i) out[i] = h[i];

  return 0;
}

int sha512(unsigned char *out, const unsigned char *in, unsigned long long inlen)
{
  unsigned char h[64];
  unsigned char padded[256];
  unsigned int i;
  unsigned long long bytes = inlen;

  for (i = 0;i < 64;++i) h[i] = iv_512[i];

  blocks(h,in,inlen);
  in += inlen;
  inlen &= 127;
  in -= inlen;

  for (i = 0;i < inlen;++i) padded[i] = in[i];
  padded[inlen] = 0x80;

  if (inlen < 112) {
    for (i = inlen + 1;i < 119;++i) padded[i] = 0;
    padded[119] = bytes >> 61;
    padded[120] = bytes >> 53;
    padded[121] = bytes >> 45;
    padded[122] = bytes >> 37;
    padded[123] = bytes >> 29;
    padded[124] = bytes >> 21;
    padded[125] = bytes >> 13;
    padded[126] = bytes >> 5;
    padded[127] = bytes << 3;
    blocks(h,padded,128);
  } else {
    for (i = inlen + 1;i < 247;++i) padded[i] = 0;
    padded[247] = bytes >> 61;
    padded[248] = bytes >> 53;
    padded[249] = bytes >> 45;
    padded[250] = bytes >> 37;
    padded[251] = bytes >> 29;
    padded[252] = bytes >> 21;
    padded[253] = bytes >> 13;
    padded[254] = bytes >> 5;
    padded[255] = bytes << 3;
    blocks(h,padded,256);
  }

  for (i = 0;i < 64;++i) out[i] = h[i];

  return 0;
}