/*
   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/>.
*/
/* blake2s.c
 *
 * Copyright (C) 2006-2020 wolfSSL Inc.
 *
 * This file is part of wolfSSL.
 *
 * wolfSSL is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * wolfSSL 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.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
 */



#ifdef HAVE_CONFIG_H
    #include <config.h>
#endif

#include <wolfssl/wolfcrypt/settings.h>

#ifdef HAVE_BLAKE2S

#include <wolfssl/wolfcrypt/blake2.h>
#include <wolfssl/wolfcrypt/blake2-impl.h>
#include <wolfssl/wolfcrypt/error-crypt.h>


static const word32 blake2s_IV[8] =
{
  0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
  0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19
};

static const byte blake2s_sigma[10][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 }
};


static WC_INLINE int blake2s_set_lastnode( blake2s_state *S )
{
  S->f[1] = ~0;
  return 0;
}

/* Some helper functions, not necessarily useful */
static WC_INLINE int blake2s_set_lastblock( blake2s_state *S )
{
  if( S->last_node ) blake2s_set_lastnode( S );

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

static WC_INLINE int blake2s_increment_counter( blake2s_state *S, const word32
                                             inc )
{
  S->t[0] += inc;
  S->t[1] += ( S->t[0] < inc );
  return 0;
}

static WC_INLINE int blake2s_init0( blake2s_state *S )
{
  int i;
  XMEMSET( S, 0, sizeof( blake2s_state ) );

  for( i = 0; i < 8; ++i ) S->h[i] = blake2s_IV[i];

  return 0;
}

/* init xors IV with input parameter block */
int blake2s_init_param( blake2s_state *S, const blake2s_param *P )
{
  word32 i;
  byte *p ;
  blake2s_init0( S );
  p =  ( byte * )( P );

  /* IV XOR ParamBlock */
  for( i = 0; i < 8; ++i )
    S->h[i] ^= load32( p + sizeof( S->h[i] ) * i );

  return 0;
}



int blake2s_init( blake2s_state *S, const byte outlen )
{
  blake2s_param P[1];

  if ( ( !outlen ) || ( outlen > BLAKE2S_OUTBYTES ) ) return BAD_FUNC_ARG;

#ifdef WOLFSSL_BLAKE2S_INIT_EACH_FIELD
  P->digest_length = outlen;
  P->key_length    = 0;
  P->fanout        = 1;
  P->depth         = 1;
  store32( &P->leaf_length, 0 );
  store32( &P->node_offset, 0 );
  P->node_depth    = 0;
  P->inner_length  = 0;
  XMEMSET( P->reserved, 0, sizeof( P->reserved ) );
  XMEMSET( P->salt,     0, sizeof( P->salt ) );
  XMEMSET( P->personal, 0, sizeof( P->personal ) );
#else
  XMEMSET( P, 0, sizeof( *P ) );
  P->digest_length = outlen;
  P->fanout        = 1;
  P->depth         = 1;
#endif
  return blake2s_init_param( S, P );
}


int blake2s_init_key( blake2s_state *S, const byte outlen, const void *key,
                      const byte keylen )
{
  blake2s_param P[1];

  if ( ( !outlen ) || ( outlen > BLAKE2S_OUTBYTES ) ) return BAD_FUNC_ARG;

  if ( !key || !keylen || keylen > BLAKE2S_KEYBYTES ) return BAD_FUNC_ARG;

#ifdef WOLFSSL_BLAKE2S_INIT_EACH_FIELD
  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;
  XMEMSET( P->reserved, 0, sizeof( P->reserved ) );
  XMEMSET( P->salt,     0, sizeof( P->salt ) );
  XMEMSET( P->personal, 0, sizeof( P->personal ) );
#else
  XMEMSET( P, 0, sizeof( *P ) );
  P->digest_length = outlen;
  P->key_length    = keylen;
  P->fanout        = 1;
  P->depth         = 1;
#endif

  {
      int ret = blake2s_init_param( S, P );
      if (ret < 0)
          return ret;
  }

  {
#ifdef WOLFSSL_SMALL_STACK
    byte* block;

    block = (byte*)XMALLOC(BLAKE2S_BLOCKBYTES, NULL, DYNAMIC_TYPE_TMP_BUFFER);

    if ( block == NULL ) return MEMORY_E;
#else
    byte block[BLAKE2S_BLOCKBYTES];
#endif

    XMEMSET( block, 0, BLAKE2S_BLOCKBYTES );
    XMEMCPY( block, key, keylen );
    blake2s_update( S, block, BLAKE2S_BLOCKBYTES );
    secure_zero_memory( block, BLAKE2S_BLOCKBYTES ); /* Burn the key from */
                                                     /* memory */

#ifdef WOLFSSL_SMALL_STACK
    XFREE(block, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
  }
  return 0;
}

static int blake2s_compress( blake2s_state *S,
                             const byte block[BLAKE2S_BLOCKBYTES] )
{
  int i;

#ifdef WOLFSSL_SMALL_STACK
  word32* m;
  word32* v;

  m = (word32*)XMALLOC(sizeof(word32) * 16, NULL, DYNAMIC_TYPE_TMP_BUFFER);

  if ( m == NULL ) return MEMORY_E;

  v = (word32*)XMALLOC(sizeof(word32) * 16, NULL, DYNAMIC_TYPE_TMP_BUFFER);

  if ( v == NULL )
  {
    XFREE(m, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    return MEMORY_E;
  }
#else
  word32 m[16];
  word32 v[16];
#endif

  for( i = 0; i < 16; ++i )
    m[i] = load32( block + i * sizeof( m[i] ) );

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

  v[ 8] = blake2s_IV[0];
  v[ 9] = blake2s_IV[1];
  v[10] = blake2s_IV[2];
  v[11] = blake2s_IV[3];
  v[12] = S->t[0] ^ blake2s_IV[4];
  v[13] = S->t[1] ^ blake2s_IV[5];
  v[14] = S->f[0] ^ blake2s_IV[6];
  v[15] = S->f[1] ^ blake2s_IV[7];
#define G(r,i,a,b,c,d) \
  do { \
    a = a + b + m[blake2s_sigma[r][2*i+0]]; \
    d = rotr32(d ^ a, 16); \
    c = c + d; \
    b = rotr32(b ^ c, 12); \
    a = a + b + m[blake2s_sigma[r][2*i+1]]; \
    d = rotr32(d ^ a, 8); \
    c = c + d; \
    b = rotr32(b ^ c, 7); \
  } 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 );

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

#undef G
#undef ROUND

#ifdef WOLFSSL_SMALL_STACK
  XFREE(m, NULL, DYNAMIC_TYPE_TMP_BUFFER);
  XFREE(v, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif

  return 0;
}

/* inlen now in bytes */
int blake2s_update( blake2s_state *S, const byte *in, word32 inlen )
{
  while( inlen > 0 )
  {
    word32 left = S->buflen;
    word32 fill = 2 * BLAKE2S_BLOCKBYTES - left;

    if( inlen > fill )
    {
      XMEMCPY( S->buf + left, in, (wolfssl_word)fill ); /* Fill buffer */
      S->buflen += fill;
      blake2s_increment_counter( S, BLAKE2S_BLOCKBYTES );

      {
          int ret= blake2s_compress( S, S->buf );
          if (ret < 0) return ret;
      }

      XMEMCPY( S->buf, S->buf + BLAKE2S_BLOCKBYTES, BLAKE2S_BLOCKBYTES );
              /* Shift buffer left */
      S->buflen -= BLAKE2S_BLOCKBYTES;
      in += fill;
      inlen -= fill;
    }
    else /* inlen <= fill */
    {
      XMEMCPY( S->buf + left, in, (wolfssl_word)inlen );
      S->buflen += inlen; /* Be lazy, do not compress */
      inlen = 0;
    }
  }

  return 0;
}

/* Is this correct? */
int blake2s_final( blake2s_state *S, byte *out, byte outlen )
{
  int     i;
  byte buffer[BLAKE2S_BLOCKBYTES];

  if( S->buflen > BLAKE2S_BLOCKBYTES )
  {
    blake2s_increment_counter( S, BLAKE2S_BLOCKBYTES );

    {
        int ret = blake2s_compress( S, S->buf );
        if (ret < 0) return ret;
    }

    S->buflen -= BLAKE2S_BLOCKBYTES;
    XMEMCPY( S->buf, S->buf + BLAKE2S_BLOCKBYTES, (wolfssl_word)S->buflen );
  }

  blake2s_increment_counter( S, S->buflen );
  blake2s_set_lastblock( S );
  XMEMSET( S->buf + S->buflen, 0, (wolfssl_word)(2 * BLAKE2S_BLOCKBYTES - S->buflen) );
         /* Padding */
  {
      int ret = blake2s_compress( S, S->buf );
      if (ret < 0) return ret;
  }

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

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

/* inlen, at least, should be word32. Others can be size_t. */
int blake2s( byte *out, const void *in, const void *key, const byte outlen,
             const word32 inlen, byte keylen )
{
  blake2s_state S[1];

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

  if ( NULL == out ) return BAD_FUNC_ARG;

  if( NULL == key ) keylen = 0;

  if( keylen > 0 )
  {
      int ret = blake2s_init_key( S, outlen, key, keylen );
      if (ret < 0) return ret;
  }
  else
  {
      int ret = blake2s_init( S, outlen );
      if (ret < 0) return ret;
  }

  {
      int ret = blake2s_update( S, ( byte * )in, inlen );
      if (ret < 0) return ret;
  }

  return blake2s_final( S, out, outlen );
}

#if defined(BLAKE2S_SELFTEST)
#include <string.h>
#include "blake2-kat.h"
int main( int argc, char **argv )
{
  byte key[BLAKE2S_KEYBYTES];
  byte buf[KAT_LENGTH];

  for( word32 i = 0; i < BLAKE2S_KEYBYTES; ++i )
    key[i] = ( byte )i;

  for( word32 i = 0; i < KAT_LENGTH; ++i )
    buf[i] = ( byte )i;

  for( word32 i = 0; i < KAT_LENGTH; ++i )
  {
    byte hash[BLAKE2S_OUTBYTES];
    if ( blake2s( hash, buf, key, BLAKE2S_OUTBYTES, i, BLAKE2S_KEYBYTES ) < 0 )
    {
      puts( "error" );
      return -1;
    }

    if( 0 != XMEMCMP( hash, blake2s_keyed_kat[i], BLAKE2S_OUTBYTES ) )
    {
      puts( "error" );
      return -1;
    }
  }

  puts( "ok" );
  return 0;
}
#endif


/* wolfCrypt API */

/* Init Blake2s digest, track size in case final doesn't want to "remember" */
int wc_InitBlake2s(Blake2s* b2s, word32 digestSz)
{
    if (b2s == NULL){
        return BAD_FUNC_ARG;
    }
    b2s->digestSz = digestSz;

    return blake2s_init(b2s->S, (byte)digestSz);
}


/* Init Blake2s digest with key, track size in case final doesn't want to "remember" */
int wc_InitBlake2s_WithKey(Blake2s* b2s, word32 digestSz, const byte *key, word32 keylen)
{
    if (b2s == NULL){
        return BAD_FUNC_ARG;
    }
    b2s->digestSz = digestSz;

    if (keylen >= 256)
        return BAD_FUNC_ARG;

    if (key)
        return blake2s_init_key(b2s->S, (byte)digestSz, key, (byte)keylen);
    else
        return blake2s_init(b2s->S, (byte)digestSz);
}


/* Blake2s Update */
int wc_Blake2sUpdate(Blake2s* b2s, const byte* data, word32 sz)
{
    return blake2s_update(b2s->S, data, sz);
}


/* Blake2s Final, if pass in zero size we use init digestSz */
int wc_Blake2sFinal(Blake2s* b2s, byte* final, word32 requestSz)
{
    word32 sz = requestSz ? requestSz : b2s->digestSz;

    return blake2s_final(b2s->S, final, (byte)sz);
}


/* end CTaoCrypt API */

#endif  /* HAVE_BLAKE2S */

