/*
   +----------------------------------------------------------------------+
   | HipHop for PHP                                                       |
   +----------------------------------------------------------------------+
   | Copyright (c) 2010-2015 Facebook, Inc. (http://www.facebook.com)     |
   | Copyright (c) 1997-2010 The PHP Group                                |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_01.txt                                  |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
*/
#include "hphp/runtime/ext/hash/hash_whirlpool.h"
#include "hphp/runtime/ext/hash/php_hash_whirlpool_tables.h"

namespace HPHP {
///////////////////////////////////////////////////////////////////////////////

typedef struct {
  uint64_t state[8];
  unsigned char bitlength[32];
  struct {
    int pos;
    int bits;
    unsigned char data[64];
  } buffer;
} PHP_WHIRLPOOL_CTX;

hash_whirlpool::hash_whirlpool() :
  HashEngine(64, 64, sizeof(PHP_WHIRLPOOL_CTX)) {
};

#define DIGESTBYTES 64
#define DIGESTBITS  (8*DIGESTBYTES) /* 512 */

#define WBLOCKBYTES 64
#define WBLOCKBITS  (8*WBLOCKBYTES) /* 512 */

#define LENGTHBYTES 32
#define LENGTHBITS  (8*LENGTHBYTES) /* 256 */

static void WhirlpoolTransform(PHP_WHIRLPOOL_CTX *context) {
  int i, r;
  uint64_t K[8];        /* the round key */
  uint64_t block[8];    /* mu(buffer) */
  uint64_t state[8];    /* the cipher state */
  uint64_t L[8];
  unsigned char *buffer = context->buffer.data;

  /*
   * map the buffer to a block:
   */
  for (i = 0; i < 8; i++, buffer += 8) {
    block[i] =
      (((uint64_t)buffer[0]        ) << 56) ^
      (((uint64_t)buffer[1] & 0xffL) << 48) ^
      (((uint64_t)buffer[2] & 0xffL) << 40) ^
      (((uint64_t)buffer[3] & 0xffL) << 32) ^
      (((uint64_t)buffer[4] & 0xffL) << 24) ^
      (((uint64_t)buffer[5] & 0xffL) << 16) ^
      (((uint64_t)buffer[6] & 0xffL) <<  8) ^
      (((uint64_t)buffer[7] & 0xffL)      );
  }
  /*
   * compute and apply K^0 to the cipher state:
   */
  state[0] = block[0] ^ (K[0] = context->state[0]);
  state[1] = block[1] ^ (K[1] = context->state[1]);
  state[2] = block[2] ^ (K[2] = context->state[2]);
  state[3] = block[3] ^ (K[3] = context->state[3]);
  state[4] = block[4] ^ (K[4] = context->state[4]);
  state[5] = block[5] ^ (K[5] = context->state[5]);
  state[6] = block[6] ^ (K[6] = context->state[6]);
  state[7] = block[7] ^ (K[7] = context->state[7]);
  /*
   * iterate over all rounds:
   */
  for (r = 1; r <= R; r++) {
    /*
     * compute K^r from K^{r-1}:
     */
    L[0] =
      C0[(int)(K[0] >> 56)       ] ^
      C1[(int)(K[7] >> 48) & 0xff] ^
      C2[(int)(K[6] >> 40) & 0xff] ^
      C3[(int)(K[5] >> 32) & 0xff] ^
      C4[(int)(K[4] >> 24) & 0xff] ^
      C5[(int)(K[3] >> 16) & 0xff] ^
      C6[(int)(K[2] >>  8) & 0xff] ^
      C7[(int)(K[1]      ) & 0xff] ^
      rc[r];
    L[1] =
      C0[(int)(K[1] >> 56)       ] ^
      C1[(int)(K[0] >> 48) & 0xff] ^
      C2[(int)(K[7] >> 40) & 0xff] ^
      C3[(int)(K[6] >> 32) & 0xff] ^
      C4[(int)(K[5] >> 24) & 0xff] ^
      C5[(int)(K[4] >> 16) & 0xff] ^
      C6[(int)(K[3] >>  8) & 0xff] ^
      C7[(int)(K[2]      ) & 0xff];
    L[2] =
      C0[(int)(K[2] >> 56)       ] ^
      C1[(int)(K[1] >> 48) & 0xff] ^
      C2[(int)(K[0] >> 40) & 0xff] ^
      C3[(int)(K[7] >> 32) & 0xff] ^
      C4[(int)(K[6] >> 24) & 0xff] ^
      C5[(int)(K[5] >> 16) & 0xff] ^
      C6[(int)(K[4] >>  8) & 0xff] ^
      C7[(int)(K[3]      ) & 0xff];
    L[3] =
      C0[(int)(K[3] >> 56)       ] ^
      C1[(int)(K[2] >> 48) & 0xff] ^
      C2[(int)(K[1] >> 40) & 0xff] ^
      C3[(int)(K[0] >> 32) & 0xff] ^
      C4[(int)(K[7] >> 24) & 0xff] ^
      C5[(int)(K[6] >> 16) & 0xff] ^
      C6[(int)(K[5] >>  8) & 0xff] ^
      C7[(int)(K[4]      ) & 0xff];
    L[4] =
      C0[(int)(K[4] >> 56)       ] ^
      C1[(int)(K[3] >> 48) & 0xff] ^
      C2[(int)(K[2] >> 40) & 0xff] ^
      C3[(int)(K[1] >> 32) & 0xff] ^
      C4[(int)(K[0] >> 24) & 0xff] ^
      C5[(int)(K[7] >> 16) & 0xff] ^
      C6[(int)(K[6] >>  8) & 0xff] ^
      C7[(int)(K[5]      ) & 0xff];
    L[5] =
      C0[(int)(K[5] >> 56)       ] ^
      C1[(int)(K[4] >> 48) & 0xff] ^
      C2[(int)(K[3] >> 40) & 0xff] ^
      C3[(int)(K[2] >> 32) & 0xff] ^
      C4[(int)(K[1] >> 24) & 0xff] ^
      C5[(int)(K[0] >> 16) & 0xff] ^
      C6[(int)(K[7] >>  8) & 0xff] ^
      C7[(int)(K[6]      ) & 0xff];
    L[6] =
      C0[(int)(K[6] >> 56)       ] ^
      C1[(int)(K[5] >> 48) & 0xff] ^
      C2[(int)(K[4] >> 40) & 0xff] ^
      C3[(int)(K[3] >> 32) & 0xff] ^
      C4[(int)(K[2] >> 24) & 0xff] ^
      C5[(int)(K[1] >> 16) & 0xff] ^
      C6[(int)(K[0] >>  8) & 0xff] ^
      C7[(int)(K[7]      ) & 0xff];
    L[7] =
      C0[(int)(K[7] >> 56)       ] ^
      C1[(int)(K[6] >> 48) & 0xff] ^
      C2[(int)(K[5] >> 40) & 0xff] ^
      C3[(int)(K[4] >> 32) & 0xff] ^
      C4[(int)(K[3] >> 24) & 0xff] ^
      C5[(int)(K[2] >> 16) & 0xff] ^
      C6[(int)(K[1] >>  8) & 0xff] ^
      C7[(int)(K[0]      ) & 0xff];
    K[0] = L[0];
    K[1] = L[1];
    K[2] = L[2];
    K[3] = L[3];
    K[4] = L[4];
    K[5] = L[5];
    K[6] = L[6];
    K[7] = L[7];
    /*
     * apply the r-th round transformation:
     */
    L[0] =
      C0[(int)(state[0] >> 56)       ] ^
      C1[(int)(state[7] >> 48) & 0xff] ^
      C2[(int)(state[6] >> 40) & 0xff] ^
      C3[(int)(state[5] >> 32) & 0xff] ^
      C4[(int)(state[4] >> 24) & 0xff] ^
      C5[(int)(state[3] >> 16) & 0xff] ^
      C6[(int)(state[2] >>  8) & 0xff] ^
      C7[(int)(state[1]      ) & 0xff] ^
      K[0];
    L[1] =
      C0[(int)(state[1] >> 56)       ] ^
      C1[(int)(state[0] >> 48) & 0xff] ^
      C2[(int)(state[7] >> 40) & 0xff] ^
      C3[(int)(state[6] >> 32) & 0xff] ^
      C4[(int)(state[5] >> 24) & 0xff] ^
      C5[(int)(state[4] >> 16) & 0xff] ^
      C6[(int)(state[3] >>  8) & 0xff] ^
      C7[(int)(state[2]      ) & 0xff] ^
      K[1];
    L[2] =
      C0[(int)(state[2] >> 56)       ] ^
      C1[(int)(state[1] >> 48) & 0xff] ^
      C2[(int)(state[0] >> 40) & 0xff] ^
      C3[(int)(state[7] >> 32) & 0xff] ^
      C4[(int)(state[6] >> 24) & 0xff] ^
      C5[(int)(state[5] >> 16) & 0xff] ^
      C6[(int)(state[4] >>  8) & 0xff] ^
      C7[(int)(state[3]      ) & 0xff] ^
      K[2];
    L[3] =
      C0[(int)(state[3] >> 56)       ] ^
      C1[(int)(state[2] >> 48) & 0xff] ^
      C2[(int)(state[1] >> 40) & 0xff] ^
      C3[(int)(state[0] >> 32) & 0xff] ^
      C4[(int)(state[7] >> 24) & 0xff] ^
      C5[(int)(state[6] >> 16) & 0xff] ^
      C6[(int)(state[5] >>  8) & 0xff] ^
      C7[(int)(state[4]      ) & 0xff] ^
      K[3];
    L[4] =
      C0[(int)(state[4] >> 56)       ] ^
      C1[(int)(state[3] >> 48) & 0xff] ^
      C2[(int)(state[2] >> 40) & 0xff] ^
      C3[(int)(state[1] >> 32) & 0xff] ^
      C4[(int)(state[0] >> 24) & 0xff] ^
      C5[(int)(state[7] >> 16) & 0xff] ^
      C6[(int)(state[6] >>  8) & 0xff] ^
      C7[(int)(state[5]      ) & 0xff] ^
      K[4];
    L[5] =
      C0[(int)(state[5] >> 56)       ] ^
      C1[(int)(state[4] >> 48) & 0xff] ^
      C2[(int)(state[3] >> 40) & 0xff] ^
      C3[(int)(state[2] >> 32) & 0xff] ^
      C4[(int)(state[1] >> 24) & 0xff] ^
      C5[(int)(state[0] >> 16) & 0xff] ^
      C6[(int)(state[7] >>  8) & 0xff] ^
      C7[(int)(state[6]      ) & 0xff] ^
      K[5];
    L[6] =
      C0[(int)(state[6] >> 56)       ] ^
      C1[(int)(state[5] >> 48) & 0xff] ^
      C2[(int)(state[4] >> 40) & 0xff] ^
      C3[(int)(state[3] >> 32) & 0xff] ^
      C4[(int)(state[2] >> 24) & 0xff] ^
      C5[(int)(state[1] >> 16) & 0xff] ^
      C6[(int)(state[0] >>  8) & 0xff] ^
      C7[(int)(state[7]      ) & 0xff] ^
      K[6];
    L[7] =
      C0[(int)(state[7] >> 56)       ] ^
      C1[(int)(state[6] >> 48) & 0xff] ^
      C2[(int)(state[5] >> 40) & 0xff] ^
      C3[(int)(state[4] >> 32) & 0xff] ^
      C4[(int)(state[3] >> 24) & 0xff] ^
      C5[(int)(state[2] >> 16) & 0xff] ^
      C6[(int)(state[1] >>  8) & 0xff] ^
      C7[(int)(state[0]      ) & 0xff] ^
      K[7];
    state[0] = L[0];
    state[1] = L[1];
    state[2] = L[2];
    state[3] = L[3];
    state[4] = L[4];
    state[5] = L[5];
    state[6] = L[6];
    state[7] = L[7];
  }
  /*
   * apply the Miyaguchi-Preneel compression function:
   */
  context->state[0] ^= state[0] ^ block[0];
  context->state[1] ^= state[1] ^ block[1];
  context->state[2] ^= state[2] ^ block[2];
  context->state[3] ^= state[3] ^ block[3];
  context->state[4] ^= state[4] ^ block[4];
  context->state[5] ^= state[5] ^ block[5];
  context->state[6] ^= state[6] ^ block[6];
  context->state[7] ^= state[7] ^ block[7];

  memset(state, 0, sizeof(state));
}

void hash_whirlpool::hash_init(void *context_) {
  PHP_WHIRLPOOL_CTX *context = (PHP_WHIRLPOOL_CTX*)context_;
  memset(context, 0, sizeof(*context));
}

void hash_whirlpool::hash_update(void *context_, const unsigned char *input,
                                 unsigned int len) {
  PHP_WHIRLPOOL_CTX *context = (PHP_WHIRLPOOL_CTX*)context_;

  uint64_t sourceBits = len * 8;
  /* index of leftmost source unsigned char containing data (1 to 8 bits). */
  int sourcePos    = 0;
  /* space on source[sourcePos]. */
  int sourceGap    = (8 - ((int)sourceBits & 7)) & 7;
  /* occupied bits on buffer[bufferPos]. */
  int bufferRem    = context->buffer.bits & 7;
  const unsigned char *source = input;
  unsigned char *buffer       = context->buffer.data;
  unsigned char *bitLength    = context->bitlength;
  int bufferBits   = context->buffer.bits;
  int bufferPos    = context->buffer.pos;
  unsigned int b, carry;
  int i;

  /*
   * tally the length of the added data:
   */
  uint64_t value = sourceBits;
  for (i = 31, carry = 0; i >= 0 && (carry != 0 || value != L64(0)); i--) {
    carry += bitLength[i] + ((unsigned int)value & 0xff);
    bitLength[i] = (unsigned char)carry;
    carry >>= 8;
    value >>= 8;
  }
  /*
   * process data in chunks of 8 bits (a more efficient approach would be to
   * take whole-word chunks):
   */
  while (sourceBits > 8) {
    /* N.B. at least source[sourcePos] and source[sourcePos+1] contain data. */
    /*
     * take a byte from the source:
     */
    b = ((source[sourcePos] << sourceGap) & 0xff) |
      ((source[sourcePos + 1] & 0xff) >> (8 - sourceGap));
    /*
     * process this byte:
     */
    buffer[bufferPos++] |= (unsigned char)(b >> bufferRem);
    bufferBits += 8 - bufferRem; /* bufferBits = 8*bufferPos; */
    if (bufferBits == DIGESTBITS) {
      /*
       * process data block:
       */
      WhirlpoolTransform(context);
      /*
       * reset buffer:
       */
      bufferBits = bufferPos = 0;
    }
    buffer[bufferPos] = (unsigned char) (b << (8 - bufferRem));
    bufferBits += bufferRem;
    /*
     * proceed to remaining data:
     */
    sourceBits -= 8;
    sourcePos++;
  }
  /* now 0 <= sourceBits <= 8;
   * furthermore, all data (if any is left) is in source[sourcePos].
   */
  if (sourceBits > 0) {
    /* bits are left-justified on b. */
    b = (source[sourcePos] << sourceGap) & 0xff;
    /*
     * process the remaining bits:
     */
    buffer[bufferPos] |= b >> bufferRem;
  } else {
    b = 0;
  }
  if (bufferRem + sourceBits < 8) {
    /*
     * all remaining data fits on buffer[bufferPos],
     * and there still remains some space.
     */
    bufferBits += (int) sourceBits;
  } else {
    /*
     * buffer[bufferPos] is full:
     */
    bufferPos++;
    bufferBits += 8 - bufferRem; /* bufferBits = 8*bufferPos; */
    sourceBits -= 8 - bufferRem;
    /* now 0 <= sourceBits < 8;
     * furthermore, all data (if any is left) is in source[sourcePos].
     */
    if (bufferBits == DIGESTBITS) {
      /*
       * process data block:
       */
      WhirlpoolTransform(context);
      /*
       * reset buffer:
       */
      bufferBits = bufferPos = 0;
    }
    buffer[bufferPos] = (unsigned char) (b << (8 - bufferRem));
    bufferBits += (int)sourceBits;
  }
  context->buffer.bits   = bufferBits;
  context->buffer.pos    = bufferPos;
}

void hash_whirlpool::hash_final(unsigned char *digest, void *context_) {
  PHP_WHIRLPOOL_CTX *context = (PHP_WHIRLPOOL_CTX*)context_;

  int i;
  unsigned char *buffer      = context->buffer.data;
  unsigned char *bitLength   = context->bitlength;
  int bufferBits  = context->buffer.bits;
  int bufferPos   = context->buffer.pos;

  /*
   * append a '1'-bit:
   */
  buffer[bufferPos] |= 0x80U >> (bufferBits & 7);
  /* all remaining bits on the current unsigned char are set to zero. */
  bufferPos++;
  /*
   * pad with zero bits to complete (N*WBLOCKBITS - LENGTHBITS) bits:
   */
  if (bufferPos > WBLOCKBYTES - LENGTHBYTES) {
    if (bufferPos < WBLOCKBYTES) {
      memset(&buffer[bufferPos], 0, WBLOCKBYTES - bufferPos);
    }
    /*
     * process data block:
     */
    WhirlpoolTransform(context);
    /*
     * reset buffer:
     */
    bufferPos = 0;
  }
  if (bufferPos < WBLOCKBYTES - LENGTHBYTES) {
    memset(&buffer[bufferPos], 0, (WBLOCKBYTES - LENGTHBYTES) - bufferPos);
  }
  bufferPos = WBLOCKBYTES - LENGTHBYTES;
  /*
   * append bit length of hashed data:
   */
  memcpy(&buffer[WBLOCKBYTES - LENGTHBYTES], bitLength, LENGTHBYTES);
  /*
   * process data block:
   */
  WhirlpoolTransform(context);
  /*
   * return the completed message digest:
   */
  for (i = 0; i < DIGESTBYTES/8; i++) {
    digest[0] = (unsigned char)(context->state[i] >> 56);
    digest[1] = (unsigned char)(context->state[i] >> 48);
    digest[2] = (unsigned char)(context->state[i] >> 40);
    digest[3] = (unsigned char)(context->state[i] >> 32);
    digest[4] = (unsigned char)(context->state[i] >> 24);
    digest[5] = (unsigned char)(context->state[i] >> 16);
    digest[6] = (unsigned char)(context->state[i] >>  8);
    digest[7] = (unsigned char)(context->state[i]      );
    digest += 8;
  }

  memset(context, 0, sizeof(*context));
}

///////////////////////////////////////////////////////////////////////////////
}
