#include "arch.h"
#if defined(JOHN_NO_SIMD) || (!defined(__SSE2__) && !defined(__SSE4_1__) && !defined(__XOP__))

/*
   BLAKE2 reference source code package - reference C implementations

   Written in 2012 by Samuel Neves <sneves@dei.uc.pt>

   To the extent possible under law, the author(s) have dedicated all copyright
   and related and neighboring rights to this software to the public domain
   worldwide. This software is distributed without any warranty.

   You should have received a copy of the CC0 Public Domain Dedication along with
   this software. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
*/

#include <stdint.h>
#include <string.h>
#include <stdio.h>

#include "blake2.h"
#include "blake2-impl.h"

static const uint64_t blake2b_IV[8] =
{
  0x6a09e667f3bcc908ULL, 0xbb67ae8584caa73bULL,
  0x3c6ef372fe94f82bULL, 0xa54ff53a5f1d36f1ULL,
  0x510e527fade682d1ULL, 0x9b05688c2b3e6c1fULL,
  0x1f83d9abfb41bd6bULL, 0x5be0cd19137e2179ULL
};

static const uint8_t blake2b_sigma[12][16] =
{
  {  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15 } ,
  { 14, 10,  4,  8,  9, 15, 13,  6,  1, 12,  0,  2, 11,  7,  5,  3 } ,
  { 11,  8, 12,  0,  5,  2, 15, 13, 10, 14,  3,  6,  7,  1,  9,  4 } ,
  {  7,  9,  3,  1, 13, 12, 11, 14,  2,  6,  5, 10,  4,  0, 15,  8 } ,
  {  9,  0,  5,  7,  2,  4, 10, 15, 14,  1, 11, 12,  6,  8,  3, 13 } ,
  {  2, 12,  6, 10,  0, 11,  8,  3,  4, 13,  7,  5, 15, 14,  1,  9 } ,
  { 12,  5,  1, 15, 14, 13,  4, 10,  0,  7,  6,  3,  9,  2,  8, 11 } ,
  { 13, 11,  7, 14, 12,  1,  3,  9,  5,  0, 15,  4,  8,  6,  2, 10 } ,
  {  6, 15, 14,  9, 11,  3,  0,  8, 12,  2, 13,  7,  1,  4, 10,  5 } ,
  { 10,  2,  8,  4,  7,  6,  1,  5, 15, 11,  9, 14,  3, 12, 13 , 0 } ,
  {  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15 } ,
  { 14, 10,  4,  8,  9, 15, 13,  6,  1, 12,  0,  2, 11,  7,  5,  3 }
};


inline static int blake2b_set_lastnode( blake2b_state *S )
{
  S->f[1] = ~0ULL;
  return 0;
}

/* Some helper functions, not necessarily useful */
inline static int blake2b_set_lastblock( blake2b_state *S )
{
  if ( S->last_node ) blake2b_set_lastnode( S );

  S->f[0] = ~0ULL;
  return 0;
}

inline static int blake2b_increment_counter( blake2b_state *S, const uint64_t inc )
{
  S->t[0] += inc;
  S->t[1] += ( S->t[0] < inc );
  return 0;
}

// Parameter-related functions
inline static int blake2b_init0( blake2b_state *S )
{
  int i;
  memset( S, 0, sizeof( blake2b_state ) );

  for ( i = 0; i < 8; ++i ) S->h[i] = blake2b_IV[i];

  return 0;
}

/* init xors IV with input parameter block */
int blake2b_init_param( blake2b_state *S, const blake2b_param *P )
{
  uint8_t *p = ( uint8_t * )( P );
  size_t i;

  blake2b_init0( S );
  /* IV XOR ParamBlock */
  for ( i = 0; i < 8; ++i )
    S->h[i] ^= load64( p + sizeof( S->h[i] ) * i );

  return 0;
}



int blake2b_init( blake2b_state *S, const uint8_t outlen )
{
  blake2b_param P[1];

  if ( ( !outlen ) || ( outlen > BLAKE2B_OUTBYTES ) ) return -1;

  P->digest_length = outlen;
  P->key_length    = 0;
  P->fanout        = 1;
  P->depth         = 1;
  store32( &P->leaf_length, 0 );
  store64( &P->node_offset, 0 );
  P->node_depth    = 0;
  P->inner_length  = 0;
  memset( P->reserved, 0, sizeof( P->reserved ) );
  memset( P->salt,     0, sizeof( P->salt ) );
  memset( P->personal, 0, sizeof( P->personal ) );
  return blake2b_init_param( S, P );
}


int blake2b_init_key( blake2b_state *S, const uint8_t outlen, const void *key, const uint8_t keylen )
{
  blake2b_param P[1];

  if ( ( !outlen ) || ( outlen > BLAKE2B_OUTBYTES ) ) return -1;

  if ( !key || !keylen || keylen > BLAKE2B_KEYBYTES ) return -1;

  P->digest_length = outlen;
  P->key_length    = keylen;
  P->fanout        = 1;
  P->depth         = 1;
  store32( &P->leaf_length, 0 );
  store64( &P->node_offset, 0 );
  P->node_depth    = 0;
  P->inner_length  = 0;
  memset( P->reserved, 0, sizeof( P->reserved ) );
  memset( P->salt,     0, sizeof( P->salt ) );
  memset( P->personal, 0, sizeof( P->personal ) );

  if ( blake2b_init_param( S, P ) < 0 ) return -1;

  {
    uint8_t block[BLAKE2B_BLOCKBYTES];
    memset( block, 0, BLAKE2B_BLOCKBYTES );
    memcpy( block, key, keylen );
    blake2b_update( S, block, BLAKE2B_BLOCKBYTES );
    //secure_zero_memory( block, BLAKE2B_BLOCKBYTES ); /* Burn the key from stack */
  }
  return 0;
}

static int blake2b_compress( blake2b_state *S, const uint8_t block[BLAKE2B_BLOCKBYTES] )
{
  uint64_t m[16];
  uint64_t v[16];
  int i;

  for ( i = 0; i < 16; ++i )
    m[i] = load64( block + i * sizeof( m[i] ) );

  for ( i = 0; i < 8; ++i )
    v[i] = S->h[i];

  v[ 8] = blake2b_IV[0];
  v[ 9] = blake2b_IV[1];
  v[10] = blake2b_IV[2];
  v[11] = blake2b_IV[3];
  v[12] = S->t[0] ^ blake2b_IV[4];
  v[13] = S->t[1] ^ blake2b_IV[5];
  v[14] = S->f[0] ^ blake2b_IV[6];
  v[15] = S->f[1] ^ blake2b_IV[7];
#define G(r,i,a,b,c,d) \
  do { \
    a = a + b + m[blake2b_sigma[r][2*i+0]]; \
    d = rotr64(d ^ a, 32); \
    c = c + d; \
    b = rotr64(b ^ c, 24); \
    a = a + b + m[blake2b_sigma[r][2*i+1]]; \
    d = rotr64(d ^ a, 16); \
    c = c + d; \
    b = rotr64(b ^ c, 63); \
  } while(0)
#define ROUND(r)  \
  do { \
    G(r,0,v[ 0],v[ 4],v[ 8],v[12]); \
    G(r,1,v[ 1],v[ 5],v[ 9],v[13]); \
    G(r,2,v[ 2],v[ 6],v[10],v[14]); \
    G(r,3,v[ 3],v[ 7],v[11],v[15]); \
    G(r,4,v[ 0],v[ 5],v[10],v[15]); \
    G(r,5,v[ 1],v[ 6],v[11],v[12]); \
    G(r,6,v[ 2],v[ 7],v[ 8],v[13]); \
    G(r,7,v[ 3],v[ 4],v[ 9],v[14]); \
  } while(0)
  ROUND( 0 );
  ROUND( 1 );
  ROUND( 2 );
  ROUND( 3 );
  ROUND( 4 );
  ROUND( 5 );
  ROUND( 6 );
  ROUND( 7 );
  ROUND( 8 );
  ROUND( 9 );
  ROUND( 10 );
  ROUND( 11 );

  for ( i = 0; i < 8; ++i )
    S->h[i] = S->h[i] ^ v[i] ^ v[i + 8];

#undef G
#undef ROUND
  return 0;
}

/* inlen now in bytes */
int blake2b_update( blake2b_state *S, const uint8_t *in, uint64_t inlen )
{
  while( inlen > 0 )
  {
    size_t left = S->buflen;
    size_t fill = 2 * BLAKE2B_BLOCKBYTES - left;

    if ( inlen > fill )
    {
      memcpy( S->buf + left, in, fill ); // Fill buffer
      S->buflen += fill;
      blake2b_increment_counter( S, BLAKE2B_BLOCKBYTES );
      blake2b_compress( S, S->buf ); // Compress
      memcpy( S->buf, S->buf + BLAKE2B_BLOCKBYTES, BLAKE2B_BLOCKBYTES ); // Shift buffer left
      S->buflen -= BLAKE2B_BLOCKBYTES;
      in += fill;
      inlen -= fill;
    }
    else // inlen <= fill
    {
      memcpy( S->buf + left, in, inlen );
      S->buflen += inlen; // Be lazy, do not compress
      in += inlen;
      inlen -= inlen;
    }
  }

  return 0;
}

/* Is this correct? */
int blake2b_final( blake2b_state *S, uint8_t *out, uint8_t outlen )
{
  uint8_t buffer[BLAKE2B_OUTBYTES];
  int i;

  if ( S->buflen > BLAKE2B_BLOCKBYTES )
  {
    blake2b_increment_counter( S, BLAKE2B_BLOCKBYTES );
    blake2b_compress( S, S->buf );
    S->buflen -= BLAKE2B_BLOCKBYTES;
    memcpy( S->buf, S->buf + BLAKE2B_BLOCKBYTES, S->buflen );
  }

  blake2b_increment_counter( S, S->buflen );
  blake2b_set_lastblock( S );
  memset( S->buf + S->buflen, 0, 2 * BLAKE2B_BLOCKBYTES - S->buflen ); /* Padding */
  blake2b_compress( S, S->buf );

  for ( i = 0; i < 8; ++i ) /* Output full hash to temp buffer */
    store64( buffer + sizeof( S->h[i] ) * i, S->h[i] );

  memcpy( out, buffer, outlen );
  return 0;
}

/* inlen, at least, should be uint64_t. Others can be size_t. */
int blake2b( uint8_t *out, const void *in, const void *key, const uint8_t outlen, const uint64_t inlen, uint8_t keylen )
{
  blake2b_state S[1];

  /* Verify parameters */
  if ( NULL == in ) return -1;

  if ( NULL == out ) return -1;

  if ( NULL == key ) keylen = 0;

  if ( keylen > 0 )
  {
    if ( blake2b_init_key( S, outlen, key, keylen ) < 0 ) return -1;
  }
  else
  {
    if ( blake2b_init( S, outlen ) < 0 ) return -1;
  }

  blake2b_update( S, ( uint8_t * )in, inlen );
  blake2b_final( S, out, outlen );
  return 0;
}

#endif
