/*

   BLAKE2 reference source code package - reference C implementations

   Copyright 2012, Samuel Neves <sneves@dei.uc.pt>.  You may use this under the

   terms of the CC0, the OpenSSL Licence, or the Apache Public License 2.0, at

   your option.  The terms of these licenses can be found at:

   - CC0 1.0 Universal : http://creativecommons.org/publicdomain/zero/1.0

   - OpenSSL license   : https://www.openssl.org/source/license.html

   - Apache 2.0        : http://www.apache.org/licenses/LICENSE-2.0

   More information about the BLAKE2 hash function can be found at

   https://blake2.net.

*/

#include <string.h>

#include "blake2b.h"

#include "blake2_common.h"

#include "memzero.h"

typedef struct trezor_blake2b_param__

{

    uint8_t  digest_length; /* 1 */

    uint8_t  key_length;    /* 2 */

    uint8_t  fanout;        /* 3 */

    uint8_t  depth;         /* 4 */

    uint32_t leaf_length;   /* 8 */

    uint32_t node_offset;   /* 12 */

    uint32_t xof_length;    /* 16 */

    uint8_t  node_depth;    /* 17 */

    uint8_t  inner_length;  /* 18 */

    uint8_t  reserved[14];  /* 32 */

    uint8_t  salt[BLAKE2B_SALTBYTES]; /* 48 */

    uint8_t  personal[BLAKE2B_PERSONALBYTES];  /* 64 */

} __attribute__((packed)) trezor_blake2b_param;

static const uint64_t trezor_blake2b_IV[8] =

{

  0x6a09e667f3bcc908ULL, 0xbb67ae8584caa73bULL,

  0x3c6ef372fe94f82bULL, 0xa54ff53a5f1d36f1ULL,

  0x510e527fade682d1ULL, 0x9b05688c2b3e6c1fULL,

  0x1f83d9abfb41bd6bULL, 0x5be0cd19137e2179ULL

};

static const uint8_t trezor_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 }

};

static void trezor_blake2b_set_lastnode( trezor_blake2b_state *S )

{

  S->f[1] = (uint64_t)-1;

}

/* Some helper functions, not necessarily useful */

static int trezor_blake2b_is_lastblock( const trezor_blake2b_state *S )

{

  return S->f[0] != 0;

}

static void trezor_blake2b_set_lastblock( trezor_blake2b_state *S )

{

  if( S->last_node ) trezor_blake2b_set_lastnode( S );

  S->f[0] = (uint64_t)-1;

}

static void trezor_blake2b_increment_counter( trezor_blake2b_state *S, const uint64_t inc )

{

  S->t[0] += inc;

  S->t[1] += ( S->t[0] < inc );

}

static void trezor_blake2b_init0( trezor_blake2b_state *S )

{

  size_t i = 0;

  memzero( S, sizeof( trezor_blake2b_state ) );

  for( i = 0; i < 8; ++i ) S->h[i] = trezor_blake2b_IV[i];

}

/* init xors IV with input parameter block */

int trezor_blake2b_init_param( trezor_blake2b_state *S, const trezor_blake2b_param *P )

{

  const uint8_t *p = ( const uint8_t * )( P );

  size_t i = 0;

  trezor_blake2b_init0( S );

  /* IV XOR ParamBlock */

  for( i = 0; i < 8; ++i )

    S->h[i] ^= load64( p + sizeof( S->h[i] ) * i );

  S->outlen = P->digest_length;

  return 0;

}

/* Sequential blake2b initialization */

int trezor_blake2b_Init( trezor_blake2b_state *S, size_t outlen )

{

  trezor_blake2b_param P[1] = {0};

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

  P->digest_length = (uint8_t)outlen;

  P->key_length    = 0;

  P->fanout        = 1;

  P->depth         = 1;

  store32( &P->leaf_length, 0 );

  store32( &P->node_offset, 0 );

  store32( &P->xof_length, 0 );

  P->node_depth    = 0;

  P->inner_length  = 0;

  memzero( P->reserved, sizeof( P->reserved ) );

  memzero( P->salt,     sizeof( P->salt ) );

  memzero( P->personal, sizeof( P->personal ) );

  return trezor_blake2b_init_param( S, P );

}

int trezor_blake2b_InitPersonal( trezor_blake2b_state *S, size_t outlen, const void *personal, size_t personal_len)

{

  trezor_blake2b_param P[1] = {0};

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

  if ( ( !personal ) || ( personal_len != BLAKE2B_PERSONALBYTES ) ) return -1;

  P->digest_length = (uint8_t)outlen;

  P->key_length    = 0;

  P->fanout        = 1;

  P->depth         = 1;

  store32( &P->leaf_length, 0 );

  store32( &P->node_offset, 0 );

  store32( &P->xof_length, 0 );

  P->node_depth    = 0;

  P->inner_length  = 0;

  memzero( P->reserved, sizeof( P->reserved ) );

  memzero( P->salt,     sizeof( P->salt ) );

  memcpy( P->personal, personal, BLAKE2B_PERSONALBYTES );

  return trezor_blake2b_init_param( S, P );

}

int trezor_blake2b_InitKey( trezor_blake2b_state *S, size_t outlen, const void *key, size_t keylen )

{

  trezor_blake2b_param P[1] = {0};

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

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

  P->digest_length = (uint8_t)outlen;

  P->key_length    = (uint8_t)keylen;

  P->fanout        = 1;

  P->depth         = 1;

  store32( &P->leaf_length, 0 );

  store32( &P->node_offset, 0 );

  store32( &P->xof_length, 0 );

  P->node_depth    = 0;

  P->inner_length  = 0;

  memzero( P->reserved, sizeof( P->reserved ) );

  memzero( P->salt,     sizeof( P->salt ) );

  memzero( P->personal, sizeof( P->personal ) );

  if( trezor_blake2b_init_param( S, P ) < 0 ) return -1;

  {

    uint8_t block[BLAKE2B_BLOCKBYTES] = {0};

    memzero( block, BLAKE2B_BLOCKBYTES );

    memcpy( block, key, keylen );

    trezor_blake2b_Update( S, block, BLAKE2B_BLOCKBYTES );

    memzero( block, BLAKE2B_BLOCKBYTES ); /* Burn the key from stack */

  }

  return 0;

}

#define G(r,i,a,b,c,d)                      \

  do {                                      \

    a = a + b + m[trezor_blake2b_sigma[r][2*i+0]]; \

    d = rotr64(d ^ a, 32);                  \

    c = c + d;                              \

    b = rotr64(b ^ c, 24);                  \

    a = a + b + m[trezor_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)

static void trezor_blake2b_compress( trezor_blake2b_state *S, const uint8_t block[BLAKE2B_BLOCKBYTES] )

{

  uint64_t m[16] = {0};

  uint64_t v[16] = {0};

  size_t i = 0;

  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] = trezor_blake2b_IV[0];

  v[ 9] = trezor_blake2b_IV[1];

  v[10] = trezor_blake2b_IV[2];

  v[11] = trezor_blake2b_IV[3];

  v[12] = trezor_blake2b_IV[4] ^ S->t[0];

  v[13] = trezor_blake2b_IV[5] ^ S->t[1];

  v[14] = trezor_blake2b_IV[6] ^ S->f[0];

  v[15] = trezor_blake2b_IV[7] ^ S->f[1];

  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

int trezor_blake2b_Update( trezor_blake2b_state *S, const void *pin, size_t inlen )

{

  const unsigned char * in = (const unsigned char *)pin;

  if( inlen > 0 )

  {

    size_t left = S->buflen;

    size_t fill = BLAKE2B_BLOCKBYTES - left;

    if( inlen > fill )

    {

      S->buflen = 0;

      memcpy( S->buf + left, in, fill ); /* Fill buffer */

      trezor_blake2b_increment_counter( S, BLAKE2B_BLOCKBYTES );

      trezor_blake2b_compress( S, S->buf ); /* Compress */

      in += fill; inlen -= fill;

      while(inlen > BLAKE2B_BLOCKBYTES) {

        trezor_blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES);

        trezor_blake2b_compress( S, in );

        in += BLAKE2B_BLOCKBYTES;

        inlen -= BLAKE2B_BLOCKBYTES;

      }

    }

    memcpy( S->buf + S->buflen, in, inlen );

    S->buflen += inlen;

  }

  return 0;

}

int trezor_blake2b_Final( trezor_blake2b_state *S, void *out, size_t outlen )

{

  uint8_t buffer[BLAKE2B_OUTBYTES] = {0};

  size_t i = 0;

  if( out == NULL || outlen < S->outlen )

    return -1;

  if( trezor_blake2b_is_lastblock( S ) )

    return -1;

  trezor_blake2b_increment_counter( S, S->buflen );

  trezor_blake2b_set_lastblock( S );

  memzero( S->buf + S->buflen, BLAKE2B_BLOCKBYTES - S->buflen ); /* Padding */

  trezor_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, S->outlen );

  memzero(buffer, sizeof(buffer));

  return 0;

}

int trezor_blake2b(const uint8_t *msg, uint32_t msg_len, void *out, size_t outlen)

{

    BLAKE2B_CTX ctx;

    if (0 != trezor_blake2b_Init(&ctx, outlen)) return -1;

    if (0 != trezor_blake2b_Update(&ctx, msg, msg_len)) return -1;

    if (0 != trezor_blake2b_Final(&ctx, out, outlen)) return -1;

    return 0;

}

int trezor_blake2b_Key(const uint8_t *msg, uint32_t msg_len, const void *key, size_t keylen, void *out, size_t outlen)

{

    BLAKE2B_CTX ctx;

    if (0 != trezor_blake2b_InitKey(&ctx, outlen, key, keylen)) return -1;

    if (0 != trezor_blake2b_Update(&ctx, msg, msg_len)) return -1;

    if (0 != trezor_blake2b_Final(&ctx, out, outlen)) return -1;

    return 0;

}