/*

 * Copyright (C) 2011-2012 Free Software Foundation, Inc.

 * Portions Copyright (C) 2001 Niels Moeller

 *

 * Author: Nikos Mavrogiannopoulos

 *

 * This file is part of GNUTLS.

 *

 * The GNUTLS library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public License

 * as published by the Free Software Foundation; either version 2.1 of

 * the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with this program.  If not, see <https://www.gnu.org/licenses/>

 *

 */

#include "gnutls_int.h"

#include "hash_int.h"

#include "errors.h"

#include <nettle/sha.h>

#include <nettle/hmac.h>

#include <nettle/macros.h>

#include "aes-padlock.h"

#include <assert.h>

#include "sha-padlock.h"

#include "x86-common.h"

#ifdef HAVE_LIBNETTLE

typedef void (*update_func)(void *, size_t, const uint8_t *);

typedef void (*digest_func)(void *, size_t, uint8_t *);

typedef void (*set_key_func)(void *, size_t, const uint8_t *);

typedef void (*init_func)(void *);

struct padlock_hash_ctx {

  union {

    struct sha1_ctx sha1;

    struct sha224_ctx sha224;

    struct sha256_ctx sha256;

    struct sha384_ctx sha384;

    struct sha512_ctx sha512;

  } ctx;

  void *ctx_ptr;

  gnutls_digest_algorithm_t algo;

  size_t length;

  update_func update;

  digest_func digest;

  init_func init;

};

static int wrap_padlock_hash_update(void *_ctx, const void *text,

            size_t textsize)

{

  struct padlock_hash_ctx *ctx = _ctx;

  ctx->update(ctx->ctx_ptr, textsize, text);

  return GNUTLS_E_SUCCESS;

}

static void wrap_padlock_hash_deinit(void *hd)

{

  gnutls_free(hd);

}

#define MD1_INCR(c) (c->count++)

#define SHA1_COMPRESS(ctx, data) \

  (padlock_sha1_blocks((void *)(ctx)->state, data, 1))

#define SHA256_COMPRESS(ctx, data) \

  (padlock_sha256_blocks((void *)(ctx)->state, data, 1))

#define SHA512_COMPRESS(ctx, data) \

  (padlock_sha512_blocks((void *)(ctx)->state, data, 1))

void padlock_sha1_update(struct sha1_ctx *ctx, size_t length,

       const uint8_t *data)

{

  MD_UPDATE(ctx, length, data, SHA1_COMPRESS, MD1_INCR(ctx));

}

void padlock_sha256_update(struct sha256_ctx *ctx, size_t length,

         const uint8_t *data)

{

  MD_UPDATE(ctx, length, data, SHA256_COMPRESS, MD1_INCR(ctx));

}

void padlock_sha512_update(struct sha512_ctx *ctx, size_t length,

         const uint8_t *data)

{

  MD_UPDATE(ctx, length, data, SHA512_COMPRESS, MD_INCR(ctx));

}

static void _nettle_write_be32(unsigned length, uint8_t *dst, uint32_t *src)

{

  unsigned i;

  unsigned words;

  unsigned leftover;

  words = length / 4;

  leftover = length % 4;

  for (i = 0; i < words; i++, dst += 4)

    WRITE_UINT32(dst, src[i]);

  if (leftover) {

    uint32_t word;

    unsigned j = leftover;

    word = src[i];

    switch (leftover) {

    default:

      abort();

    case 3:

      dst[--j] = (word >> 8) & 0xff;

      FALLTHROUGH;

    case 2:

      dst[--j] = (word >> 16) & 0xff;

      FALLTHROUGH;

    case 1:

      dst[--j] = (word >> 24) & 0xff;

    }

  }

}

static void padlock_sha1_digest(struct sha1_ctx *ctx, size_t length,

        uint8_t *digest)

{

  uint64_t bit_count;

  assert(length <= SHA1_DIGEST_SIZE);

  MD_PAD(ctx, 8, SHA1_COMPRESS);

  /* There are 512 = 2^9 bits in one block */

  bit_count = (ctx->count << 9) | (ctx->index << 3);

  /* append the 64 bit count */

  WRITE_UINT64(ctx->block + (SHA1_BLOCK_SIZE - 8), bit_count);

  SHA1_COMPRESS(ctx, ctx->block);

  _nettle_write_be32(length, digest, ctx->state);

}

static void padlock_sha256_digest(struct sha256_ctx *ctx, size_t length,

          uint8_t *digest)

{

  uint64_t bit_count;

  assert(length <= SHA256_DIGEST_SIZE);

  MD_PAD(ctx, 8, SHA256_COMPRESS);

  /* There are 512 = 2^9 bits in one block */

  bit_count = (ctx->count << 9) | (ctx->index << 3);

  /* This is slightly inefficient, as the numbers are converted to

     big-endian format, and will be converted back by the compression

     function. It's probably not worth the effort to fix this. */

  WRITE_UINT64(ctx->block + (SHA256_BLOCK_SIZE - 8), bit_count);

  SHA256_COMPRESS(ctx, ctx->block);

  _nettle_write_be32(length, digest, ctx->state);

}

static void padlock_sha512_digest(struct sha512_ctx *ctx, size_t length,

          uint8_t *digest)

{

  uint64_t high, low;

  unsigned i;

  unsigned words;

  unsigned leftover;

  assert(length <= SHA512_DIGEST_SIZE);

  MD_PAD(ctx, 16, SHA512_COMPRESS);

  /* There are 1024 = 2^10 bits in one block */

  high = (ctx->count_high << 10) | (ctx->count_low >> 54);

  low = (ctx->count_low << 10) | (ctx->index << 3);

  /* This is slightly inefficient, as the numbers are converted to

     big-endian format, and will be converted back by the compression

     function. It's probably not worth the effort to fix this. */

  WRITE_UINT64(ctx->block + (SHA512_DATA_SIZE - 16), high);

  WRITE_UINT64(ctx->block + (SHA512_DATA_SIZE - 8), low);

  SHA512_COMPRESS(ctx, ctx->block);

  words = length / 8;

  leftover = length % 8;

  for (i = 0; i < words; i++, digest += 8)

    WRITE_UINT64(digest, ctx->state[i]);

  if (leftover) {

    /* Truncate to the right size */

    uint64_t word = ctx->state[i] >> (8 * (8 - leftover));

    do {

      digest[--leftover] = word & 0xff;

      word >>= 8;

    } while (leftover);

  }

}

static int _ctx_init(gnutls_digest_algorithm_t algo,

         struct padlock_hash_ctx *ctx)

{

  switch (algo) {

  case GNUTLS_DIG_SHA1:

    sha1_init(&ctx->ctx.sha1);

    ctx->update = (update_func)padlock_sha1_update;

    ctx->digest = (digest_func)padlock_sha1_digest;

    ctx->init = (init_func)sha1_init;

    ctx->ctx_ptr = &ctx->ctx.sha1;

    ctx->length = SHA1_DIGEST_SIZE;

    break;

  case GNUTLS_DIG_SHA224:

    sha224_init(&ctx->ctx.sha224);

    ctx->update = (update_func)padlock_sha256_update;

    ctx->digest = (digest_func)padlock_sha256_digest;

    ctx->init = (init_func)sha224_init;

    ctx->ctx_ptr = &ctx->ctx.sha224;

    ctx->length = SHA224_DIGEST_SIZE;

    break;

  case GNUTLS_DIG_SHA256:

    sha256_init(&ctx->ctx.sha256);

    ctx->update = (update_func)padlock_sha256_update;

    ctx->digest = (digest_func)padlock_sha256_digest;

    ctx->init = (init_func)sha256_init;

    ctx->ctx_ptr = &ctx->ctx.sha256;

    ctx->length = SHA256_DIGEST_SIZE;

    break;

  case GNUTLS_DIG_SHA384:

    sha384_init(&ctx->ctx.sha384);

    ctx->update = (update_func)padlock_sha512_update;

    ctx->digest = (digest_func)padlock_sha512_digest;

    ctx->init = (init_func)sha384_init;

    ctx->ctx_ptr = &ctx->ctx.sha384;

    ctx->length = SHA384_DIGEST_SIZE;

    break;

  case GNUTLS_DIG_SHA512:

    sha512_init(&ctx->ctx.sha512);

    ctx->update = (update_func)padlock_sha512_update;

    ctx->digest = (digest_func)padlock_sha512_digest;

    ctx->init = (init_func)sha512_init;

    ctx->ctx_ptr = &ctx->ctx.sha512;

    ctx->length = SHA512_DIGEST_SIZE;

    break;

  default:

    gnutls_assert();

    return GNUTLS_E_INVALID_REQUEST;

  }

  return 0;

}

static int wrap_padlock_hash_init(gnutls_digest_algorithm_t algo, void **_ctx)

{

  struct padlock_hash_ctx *ctx;

  int ret;

  ctx = gnutls_malloc(sizeof(struct padlock_hash_ctx));

  if (ctx == NULL) {

    gnutls_assert();

    return GNUTLS_E_MEMORY_ERROR;

  }

  ctx->algo = algo;

  if ((ret = _ctx_init(algo, ctx)) < 0) {

    gnutls_assert();

    return ret;

  }

  *_ctx = ctx;

  return 0;

}

static void *wrap_padlock_hash_copy(const void *_ctx)

{

  struct padlock_hash_ctx *new_ctx;

  const struct padlock_hash_ctx *ctx = _ctx;

  ptrdiff_t off = (uint8_t *)ctx->ctx_ptr - (uint8_t *)(&ctx->ctx);

  new_ctx = gnutls_malloc(sizeof(struct padlock_hash_ctx));

  if (new_ctx == NULL) {

    gnutls_assert();

    return NULL;

  }

  memcpy(new_ctx, ctx, sizeof(*new_ctx));

  new_ctx->ctx_ptr = (uint8_t *)&new_ctx->ctx + off;

  return new_ctx;

}

static int wrap_padlock_hash_output(void *src_ctx, void *digest,

            size_t digestsize)

{

  struct padlock_hash_ctx *ctx;

  ctx = src_ctx;

  if (digestsize < ctx->length)

    return gnutls_assert_val(GNUTLS_E_SHORT_MEMORY_BUFFER);

  ctx->digest(ctx->ctx_ptr, digestsize, digest);

  ctx->init(ctx->ctx_ptr);

  return 0;

}

int wrap_padlock_hash_fast(gnutls_digest_algorithm_t algo, const void *text,

         size_t text_size, void *digest)

{

  if (text_size == 0 && text == NULL)

    text = digest;

  if (algo == GNUTLS_DIG_SHA1) {

    uint32_t iv[5] = {

      0x67452301UL, 0xEFCDAB89UL, 0x98BADCFEUL,

      0x10325476UL, 0xC3D2E1F0UL,

    };

    padlock_sha1_oneshot(iv, text, text_size);

    _nettle_write_be32(20, digest, iv);

  } else if (algo == GNUTLS_DIG_SHA256) {

    uint32_t iv[8] = {

      0x6a09e667UL, 0xbb67ae85UL, 0x3c6ef372UL, 0xa54ff53aUL,

      0x510e527fUL, 0x9b05688cUL, 0x1f83d9abUL, 0x5be0cd19UL,

    };

    padlock_sha256_oneshot(iv, text, text_size);

    _nettle_write_be32(32, digest, iv);

  } else {

    struct padlock_hash_ctx ctx;

    int ret;

    ret = _ctx_init(algo, &ctx);

    if (ret < 0)

      return gnutls_assert_val(ret);

    ctx.algo = algo;

    wrap_padlock_hash_update(&ctx, text, text_size);

    wrap_padlock_hash_output(&ctx, digest, ctx.length);

  }

  return 0;

}

const struct nettle_hash padlock_sha1 =

  NN_HASH(sha1, padlock_sha1_update, padlock_sha1_digest, SHA1);

const struct nettle_hash padlock_sha224 =

  NN_HASH(sha224, padlock_sha256_update, padlock_sha256_digest, SHA224);

const struct nettle_hash padlock_sha256 =

  NN_HASH(sha256, padlock_sha256_update, padlock_sha256_digest, SHA256);

const struct nettle_hash padlock_sha384 =

  NN_HASH(sha384, padlock_sha512_update, padlock_sha512_digest, SHA384);

const struct nettle_hash padlock_sha512 =

  NN_HASH(sha512, padlock_sha512_update, padlock_sha512_digest, SHA512);

const gnutls_crypto_digest_st _gnutls_sha_padlock_oneshot = {

  .init = NULL,

  .hash = NULL,

  .output = NULL,

  .deinit = NULL,

  .fast = wrap_padlock_hash_fast

};

const gnutls_crypto_digest_st _gnutls_sha_padlock = {

  .init = wrap_padlock_hash_init,

  .hash = wrap_padlock_hash_update,

  .output = wrap_padlock_hash_output,

  .copy = wrap_padlock_hash_copy,

  .deinit = wrap_padlock_hash_deinit,

  .fast = wrap_padlock_hash_fast,

};

#endif /* HAVE_LIBNETTLE */