text: /*
   *  Implementation of NIST SP 800-38F key wrapping, supporting KW and KWP modes
   *  only
   *
   *  Copyright (C) 2018, Arm Limited (or its affiliates), All Rights Reserved
   *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
   *
   *  This file is provided under the Apache License 2.0, or the
   *  GNU General Public License v2.0 or later.
   *
   *  **********
   *  Apache License 2.0:
   *
   *  Licensed under the Apache License, Version 2.0 (the "License"); you may
   *  not use this file except in compliance with the License.
   *  You may obtain a copy of the License at
   *
   *  http://www.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   *
   *  **********
   *
   *  **********
   *  GNU General Public License v2.0 or later:
   *
   *  This program 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.
   *
   *  This program 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 02110-1301 USA.
   *
   *  **********
   *
   *  This file is part of Mbed TLS (https://tls.mbed.org)
   */
  /*
   * Definition of Key Wrapping:
   * https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-38F.pdf
   * RFC 3394 "Advanced Encryption Standard (AES) Key Wrap Algorithm"
   * RFC 5649 "Advanced Encryption Standard (AES) Key Wrap with Padding Algorithm"
   *
   * Note: RFC 3394 defines different methodology for intermediate operations for
   * the wrapping and unwrapping operation than the definition in NIST SP 800-38F.
   */
  
  #if !defined(MBEDTLS_CONFIG_FILE)
  #include "mbedtls/config.h"
  #else
  #include MBEDTLS_CONFIG_FILE
  #endif
  
  #if defined(MBEDTLS_NIST_KW_C)
  
  #include "mbedtls/nist_kw.h"
  #include "mbedtls/platform_util.h"
  
  #include <stdint.h>
  #include <string.h>
  
  #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
  #if defined(MBEDTLS_PLATFORM_C)
  #include "mbedtls/platform.h"
  #else
  #include <stdio.h>
  #define mbedtls_printf printf
  #endif /* MBEDTLS_PLATFORM_C */
  #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
  
  #if !defined(MBEDTLS_NIST_KW_ALT)
  
  #define KW_SEMIBLOCK_LENGTH    8
  #define MIN_SEMIBLOCKS_COUNT   3
  
  /* constant-time buffer comparison */
  static inline unsigned char mbedtls_nist_kw_safer_memcmp( const void *a, const void *b, size_t n )
  {
      size_t i;
      volatile const unsigned char *A = (volatile const unsigned char *) a;
      volatile const unsigned char *B = (volatile const unsigned char *) b;
      volatile unsigned char diff = 0;
  
      for( i = 0; i < n; i++ )
      {
          /* Read volatile data in order before computing diff.
           * This avoids IAR compiler warning:
           * 'the order of volatile accesses is undefined ..' */
          unsigned char x = A[i], y = B[i];
          diff |= x ^ y;
      }
  
      return( diff );
  }
  
  /*! The 64-bit default integrity check value (ICV) for KW mode. */
  static const unsigned char NIST_KW_ICV1[] = {0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6};
  /*! The 32-bit default integrity check value (ICV) for KWP mode. */
  static const  unsigned char NIST_KW_ICV2[] = {0xA6, 0x59, 0x59, 0xA6};
  
  #ifndef GET_UINT32_BE
  #define GET_UINT32_BE(n,b,i)                            \
  do {                                                    \
      (n) = ( (uint32_t) (b)[(i)    ] << 24 )             \
          | ( (uint32_t) (b)[(i) + 1] << 16 )             \
          | ( (uint32_t) (b)[(i) + 2] <<  8 )             \
          | ( (uint32_t) (b)[(i) + 3]       );            \
  } while( 0 )
  #endif
  
  #ifndef PUT_UINT32_BE
  #define PUT_UINT32_BE(n,b,i)                            \
  do {                                                    \
      (b)[(i)    ] = (unsigned char) ( (n) >> 24 );       \
      (b)[(i) + 1] = (unsigned char) ( (n) >> 16 );       \
      (b)[(i) + 2] = (unsigned char) ( (n) >>  8 );       \
      (b)[(i) + 3] = (unsigned char) ( (n)       );       \
  } while( 0 )
  #endif
  
  /*
   * Initialize context
   */
  void mbedtls_nist_kw_init( mbedtls_nist_kw_context *ctx )
  {
      memset( ctx, 0, sizeof( mbedtls_nist_kw_context ) );
  }
  
  int mbedtls_nist_kw_setkey( mbedtls_nist_kw_context *ctx,
                              mbedtls_cipher_id_t cipher,
                              const unsigned char *key,
                              unsigned int keybits,
                              const int is_wrap )
  {
      int ret;
      const mbedtls_cipher_info_t *cipher_info;
  
      cipher_info = mbedtls_cipher_info_from_values( cipher,
                                                     keybits,
                                                     MBEDTLS_MODE_ECB );
      if( cipher_info == NULL )
          return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
  
      if( cipher_info->block_size != 16 )
          return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
  
      /*
       * SP 800-38F currently defines AES cipher as the only block cipher allowed:
       * "For KW and KWP, the underlying block cipher shall be approved, and the
       *  block size shall be 128 bits. Currently, the AES block cipher, with key
       *  lengths of 128, 192, or 256 bits, is the only block cipher that fits
       *  this profile."
       *  Currently we don't support other 128 bit block ciphers for key wrapping,
       *  such as Camellia and Aria.
       */
      if( cipher != MBEDTLS_CIPHER_ID_AES )
          return( MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE );
  
      mbedtls_cipher_free( &ctx->cipher_ctx );
  
      if( ( ret = mbedtls_cipher_setup( &ctx->cipher_ctx, cipher_info ) ) != 0 )
          return( ret );
  
      if( ( ret = mbedtls_cipher_setkey( &ctx->cipher_ctx, key, keybits,
                                         is_wrap ? MBEDTLS_ENCRYPT :
                                                   MBEDTLS_DECRYPT )
                                                                     ) != 0 )
      {
          return( ret );
      }
  
      return( 0 );
  }
  
  /*
   * Free context
   */
  void mbedtls_nist_kw_free( mbedtls_nist_kw_context *ctx )
  {
      mbedtls_cipher_free( &ctx->cipher_ctx );
      mbedtls_platform_zeroize( ctx, sizeof( mbedtls_nist_kw_context ) );
  }
  
  /*
   * Helper function for Xoring the uint64_t "t" with the encrypted A.
   * Defined in NIST SP 800-38F section 6.1
   */
  static void calc_a_xor_t( unsigned char A[KW_SEMIBLOCK_LENGTH], uint64_t t )
  {
      size_t i = 0;
      for( i = 0; i < sizeof( t ); i++ )
      {
          A[i] ^= ( t >> ( ( sizeof( t ) - 1 - i ) * 8 ) ) & 0xff;
      }
  }
  
  /*
   * KW-AE as defined in SP 800-38F section 6.2
   * KWP-AE as defined in SP 800-38F section 6.3
   */
  int mbedtls_nist_kw_wrap( mbedtls_nist_kw_context *ctx,
                            mbedtls_nist_kw_mode_t mode,
                            const unsigned char *input, size_t in_len,
                            unsigned char *output, size_t *out_len, size_t out_size )
  {
      int ret = 0;
      size_t semiblocks = 0;
      size_t s;
      size_t olen, padlen = 0;
      uint64_t t = 0;
      unsigned char outbuff[KW_SEMIBLOCK_LENGTH * 2];
      unsigned char inbuff[KW_SEMIBLOCK_LENGTH * 2];
      unsigned char *R2 = output + KW_SEMIBLOCK_LENGTH;
      unsigned char *A = output;
  
      *out_len = 0;
      /*
       * Generate the String to work on
       */
      if( mode == MBEDTLS_KW_MODE_KW )
      {
          if( out_size < in_len + KW_SEMIBLOCK_LENGTH )
          {
              return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
          }
  
          /*
           * According to SP 800-38F Table 1, the plaintext length for KW
           * must be between 2 to 2^54-1 semiblocks inclusive.
           */
          if( in_len < 16 ||
  #if SIZE_MAX > 0x1FFFFFFFFFFFFF8
              in_len > 0x1FFFFFFFFFFFFF8 ||
  #endif
              in_len % KW_SEMIBLOCK_LENGTH != 0 )
          {
              return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
          }
  
          memcpy( output, NIST_KW_ICV1, KW_SEMIBLOCK_LENGTH );
          memmove( output + KW_SEMIBLOCK_LENGTH, input, in_len );
      }
      else
      {
          if( in_len % 8 != 0 )
          {
              padlen = ( 8 - ( in_len % 8 ) );
          }
  
          if( out_size < in_len + KW_SEMIBLOCK_LENGTH + padlen )
          {
              return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
          }
  
          /*
           * According to SP 800-38F Table 1, the plaintext length for KWP
           * must be between 1 and 2^32-1 octets inclusive.
           */
          if( in_len < 1
  #if SIZE_MAX > 0xFFFFFFFF
              || in_len > 0xFFFFFFFF
  #endif
            )
          {
              return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
          }
  
          memcpy( output, NIST_KW_ICV2, KW_SEMIBLOCK_LENGTH / 2 );
          PUT_UINT32_BE( ( in_len & 0xffffffff ), output,
                         KW_SEMIBLOCK_LENGTH / 2 );
  
          memcpy( output + KW_SEMIBLOCK_LENGTH, input, in_len );
          memset( output + KW_SEMIBLOCK_LENGTH + in_len, 0, padlen );
      }
      semiblocks = ( ( in_len + padlen ) / KW_SEMIBLOCK_LENGTH ) + 1;
  
      s = 6 * ( semiblocks - 1 );
  
      if( mode == MBEDTLS_KW_MODE_KWP
          && in_len <= KW_SEMIBLOCK_LENGTH )
      {
          memcpy( inbuff, output, 16 );
          ret = mbedtls_cipher_update( &ctx->cipher_ctx,
                                       inbuff, 16, output, &olen );
          if( ret != 0 )
              goto cleanup;
      }
      else
      {
          /*
           * Do the wrapping function W, as defined in RFC 3394 section 2.2.1
           */
          if( semiblocks < MIN_SEMIBLOCKS_COUNT )
          {
              ret = MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
              goto cleanup;
          }
  
          /* Calculate intermediate values */
          for( t = 1; t <= s; t++ )
          {
              memcpy( inbuff, A, KW_SEMIBLOCK_LENGTH );
              memcpy( inbuff + KW_SEMIBLOCK_LENGTH, R2, KW_SEMIBLOCK_LENGTH );
  
              ret = mbedtls_cipher_update( &ctx->cipher_ctx,
                                           inbuff, 16, outbuff, &olen );
              if( ret != 0 )
                  goto cleanup;
  
              memcpy( A, outbuff, KW_SEMIBLOCK_LENGTH );
              calc_a_xor_t( A, t );
  
              memcpy( R2, outbuff + KW_SEMIBLOCK_LENGTH, KW_SEMIBLOCK_LENGTH );
              R2 += KW_SEMIBLOCK_LENGTH;
              if( R2 >= output + ( semiblocks * KW_SEMIBLOCK_LENGTH ) )
                  R2 = output + KW_SEMIBLOCK_LENGTH;
          }
      }
  
      *out_len = semiblocks * KW_SEMIBLOCK_LENGTH;
  
  cleanup:
  
      if( ret != 0)
      {
          memset( output, 0, semiblocks * KW_SEMIBLOCK_LENGTH );
      }
      mbedtls_platform_zeroize( inbuff, KW_SEMIBLOCK_LENGTH * 2 );
      mbedtls_platform_zeroize( outbuff, KW_SEMIBLOCK_LENGTH * 2 );
  
      return( ret );
  }
  
  /*
   * W-1 function as defined in RFC 3394 section 2.2.2
   * This function assumes the following:
   * 1. Output buffer is at least of size ( semiblocks - 1 ) * KW_SEMIBLOCK_LENGTH.
   * 2. The input buffer is of size semiblocks * KW_SEMIBLOCK_LENGTH.
   * 3. Minimal number of semiblocks is 3.
   * 4. A is a buffer to hold the first semiblock of the input buffer.
   */
  static int unwrap( mbedtls_nist_kw_context *ctx,
                     const unsigned char *input, size_t semiblocks,
                     unsigned char A[KW_SEMIBLOCK_LENGTH],
                     unsigned char *output, size_t* out_len )
  {
      int ret = 0;
      const size_t s = 6 * ( semiblocks - 1 );
      size_t olen;
      uint64_t t = 0;
      unsigned char outbuff[KW_SEMIBLOCK_LENGTH * 2];
      unsigned char inbuff[KW_SEMIBLOCK_LENGTH * 2];
      unsigned char *R = output + ( semiblocks - 2 ) * KW_SEMIBLOCK_LENGTH;
      *out_len = 0;
  
      if( semiblocks < MIN_SEMIBLOCKS_COUNT )
      {
          return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
      }
  
      memcpy( A, input, KW_SEMIBLOCK_LENGTH );
      memmove( output, input + KW_SEMIBLOCK_LENGTH, ( semiblocks - 1 ) * KW_SEMIBLOCK_LENGTH );
  
      /* Calculate intermediate values */
      for( t = s; t >= 1; t-- )
      {
          calc_a_xor_t( A, t );
  
          memcpy( inbuff, A, KW_SEMIBLOCK_LENGTH );
          memcpy( inbuff + KW_SEMIBLOCK_LENGTH, R, KW_SEMIBLOCK_LENGTH );
  
          ret = mbedtls_cipher_update( &ctx->cipher_ctx,
                                       inbuff, 16, outbuff, &olen );
          if( ret != 0 )
              goto cleanup;
  
          memcpy( A, outbuff, KW_SEMIBLOCK_LENGTH );
  
          /* Set R as LSB64 of outbuff */
          memcpy( R, outbuff + KW_SEMIBLOCK_LENGTH, KW_SEMIBLOCK_LENGTH );
  
          if( R == output )
              R = output + ( semiblocks - 2 ) * KW_SEMIBLOCK_LENGTH;
          else
              R -= KW_SEMIBLOCK_LENGTH;
      }
  
      *out_len = ( semiblocks - 1 ) * KW_SEMIBLOCK_LENGTH;
  
  cleanup:
      if( ret != 0)
          memset( output, 0, ( semiblocks - 1 ) * KW_SEMIBLOCK_LENGTH );
      mbedtls_platform_zeroize( inbuff, sizeof( inbuff )  );
      mbedtls_platform_zeroize( outbuff, sizeof( outbuff ) );
  
      return( ret );
  }
  
  /*
   * KW-AD as defined in SP 800-38F section 6.2
   * KWP-AD as defined in SP 800-38F section 6.3
   */
  int mbedtls_nist_kw_unwrap( mbedtls_nist_kw_context *ctx,
                              mbedtls_nist_kw_mode_t mode,
                              const unsigned char *input, size_t in_len,
                              unsigned char *output, size_t *out_len, size_t out_size )
  {
      int ret = 0;
      size_t i, olen;
      unsigned char A[KW_SEMIBLOCK_LENGTH];
      unsigned char diff, bad_padding = 0;
  
      *out_len = 0;
      if( out_size < in_len - KW_SEMIBLOCK_LENGTH )
      {
          return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
      }
  
      if( mode == MBEDTLS_KW_MODE_KW )
      {
          /*
           * According to SP 800-38F Table 1, the ciphertext length for KW
           * must be between 3 to 2^54 semiblocks inclusive.
           */
          if( in_len < 24 ||
  #if SIZE_MAX > 0x200000000000000
              in_len > 0x200000000000000 ||
  #endif
              in_len % KW_SEMIBLOCK_LENGTH != 0 )
          {
              return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
          }
  
          ret = unwrap( ctx, input, in_len / KW_SEMIBLOCK_LENGTH,
                        A, output, out_len );
          if( ret != 0 )
              goto cleanup;
  
          /* Check ICV in "constant-time" */
          diff = mbedtls_nist_kw_safer_memcmp( NIST_KW_ICV1, A, KW_SEMIBLOCK_LENGTH );
  
          if( diff != 0 )
          {
              ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
              goto cleanup;
          }
  
      }
      else if( mode == MBEDTLS_KW_MODE_KWP )
      {
          size_t padlen = 0;
          uint32_t Plen;
          /*
           * According to SP 800-38F Table 1, the ciphertext length for KWP
           * must be between 2 to 2^29 semiblocks inclusive.
           */
          if( in_len < KW_SEMIBLOCK_LENGTH * 2 ||
  #if SIZE_MAX > 0x100000000
              in_len > 0x100000000 ||
  #endif
              in_len % KW_SEMIBLOCK_LENGTH != 0 )
          {
              return(  MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
          }
  
          if( in_len == KW_SEMIBLOCK_LENGTH * 2 )
          {
              unsigned char outbuff[KW_SEMIBLOCK_LENGTH * 2];
              ret = mbedtls_cipher_update( &ctx->cipher_ctx,
                                           input, 16, outbuff, &olen );
              if( ret != 0 )
                  goto cleanup;
  
              memcpy( A, outbuff, KW_SEMIBLOCK_LENGTH );
              memcpy( output, outbuff + KW_SEMIBLOCK_LENGTH, KW_SEMIBLOCK_LENGTH );
              mbedtls_platform_zeroize( outbuff, sizeof( outbuff ) );
              *out_len = KW_SEMIBLOCK_LENGTH;
          }
          else
          {
              /* in_len >=  KW_SEMIBLOCK_LENGTH * 3 */
              ret = unwrap( ctx, input, in_len / KW_SEMIBLOCK_LENGTH,
                            A, output, out_len );
              if( ret != 0 )
                  goto cleanup;
          }
  
          /* Check ICV in "constant-time" */
          diff = mbedtls_nist_kw_safer_memcmp( NIST_KW_ICV2, A, KW_SEMIBLOCK_LENGTH / 2 );
  
          if( diff != 0 )
          {
              ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
          }
  
          GET_UINT32_BE( Plen, A, KW_SEMIBLOCK_LENGTH / 2 );
  
          /*
           * Plen is the length of the plaintext, when the input is valid.
           * If Plen is larger than the plaintext and padding, padlen will be
           * larger than 8, because of the type wrap around.
           */
          padlen = in_len - KW_SEMIBLOCK_LENGTH - Plen;
          if ( padlen > 7 )
          {
              padlen &= 7;
              ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
          }
  
          /* Check padding in "constant-time" */
          for( diff = 0, i = 0; i < KW_SEMIBLOCK_LENGTH; i++ )
          {
               if( i >= KW_SEMIBLOCK_LENGTH - padlen )
                   diff |= output[*out_len - KW_SEMIBLOCK_LENGTH + i];
               else
                   bad_padding |= output[*out_len - KW_SEMIBLOCK_LENGTH + i];
          }
  
          if( diff != 0 )
          {
              ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
          }
  
          if( ret != 0 )
          {
              goto cleanup;
          }
          memset( output + Plen, 0, padlen );
          *out_len = Plen;
      }
      else
      {
          ret = MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
          goto cleanup;
      }
  
  cleanup:
      if( ret != 0 )
      {
          memset( output, 0, *out_len );
          *out_len = 0;
      }
  
      mbedtls_platform_zeroize( &bad_padding, sizeof( bad_padding) );
      mbedtls_platform_zeroize( &diff, sizeof( diff ) );
      mbedtls_platform_zeroize( A, sizeof( A ) );
  
      return( ret );
  }
  
  #endif /* !MBEDTLS_NIST_KW_ALT */
  
  #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
  
  #define KW_TESTS 3
  
  /*
   * Test vectors taken from NIST
   * https://csrc.nist.gov/Projects/Cryptographic-Algorithm-Validation-Program/CAVP-TESTING-BLOCK-CIPHER-MODES#KW
   */
  static const unsigned int key_len[KW_TESTS] = { 16, 24, 32 };
  
  static const unsigned char kw_key[KW_TESTS][32] = {
      { 0x75, 0x75, 0xda, 0x3a, 0x93, 0x60, 0x7c, 0xc2,
        0xbf, 0xd8, 0xce, 0xc7, 0xaa, 0xdf, 0xd9, 0xa6 },
      { 0x2d, 0x85, 0x26, 0x08, 0x1d, 0x02, 0xfb, 0x5b,
        0x85, 0xf6, 0x9a, 0xc2, 0x86, 0xec, 0xd5, 0x7d,
        0x40, 0xdf, 0x5d, 0xf3, 0x49, 0x47, 0x44, 0xd3 },
      { 0x11, 0x2a, 0xd4, 0x1b, 0x48, 0x56, 0xc7, 0x25,
        0x4a, 0x98, 0x48, 0xd3, 0x0f, 0xdd, 0x78, 0x33,
        0x5b, 0x03, 0x9a, 0x48, 0xa8, 0x96, 0x2c, 0x4d,
        0x1c, 0xb7, 0x8e, 0xab, 0xd5, 0xda, 0xd7, 0x88 }
  };
  
  static const unsigned char kw_msg[KW_TESTS][40] = {
      { 0x42, 0x13, 0x6d, 0x3c, 0x38, 0x4a, 0x3e, 0xea,
        0xc9, 0x5a, 0x06, 0x6f, 0xd2, 0x8f, 0xed, 0x3f },
      { 0x95, 0xc1, 0x1b, 0xf5, 0x35, 0x3a, 0xfe, 0xdb,
        0x98, 0xfd, 0xd6, 0xc8, 0xca, 0x6f, 0xdb, 0x6d,
        0xa5, 0x4b, 0x74, 0xb4, 0x99, 0x0f, 0xdc, 0x45,
        0xc0, 0x9d, 0x15, 0x8f, 0x51, 0xce, 0x62, 0x9d,
        0xe2, 0xaf, 0x26, 0xe3, 0x25, 0x0e, 0x6b, 0x4c },
      { 0x1b, 0x20, 0xbf, 0x19, 0x90, 0xb0, 0x65, 0xd7,
        0x98, 0xe1, 0xb3, 0x22, 0x64, 0xad, 0x50, 0xa8,
        0x74, 0x74, 0x92, 0xba, 0x09, 0xa0, 0x4d, 0xd1 }
  };
  
  static const size_t kw_msg_len[KW_TESTS] = { 16, 40, 24 };
  static const size_t kw_out_len[KW_TESTS] = { 24, 48, 32 };
  static const unsigned char kw_res[KW_TESTS][48] = {
      { 0x03, 0x1f, 0x6b, 0xd7, 0xe6, 0x1e, 0x64, 0x3d,
        0xf6, 0x85, 0x94, 0x81, 0x6f, 0x64, 0xca, 0xa3,
        0xf5, 0x6f, 0xab, 0xea, 0x25, 0x48, 0xf5, 0xfb },
      { 0x44, 0x3c, 0x6f, 0x15, 0x09, 0x83, 0x71, 0x91,
        0x3e, 0x5c, 0x81, 0x4c, 0xa1, 0xa0, 0x42, 0xec,
        0x68, 0x2f, 0x7b, 0x13, 0x6d, 0x24, 0x3a, 0x4d,
        0x6c, 0x42, 0x6f, 0xc6, 0x97, 0x15, 0x63, 0xe8,
        0xa1, 0x4a, 0x55, 0x8e, 0x09, 0x64, 0x16, 0x19,
        0xbf, 0x03, 0xfc, 0xaf, 0x90, 0xb1, 0xfc, 0x2d },
      { 0xba, 0x8a, 0x25, 0x9a, 0x47, 0x1b, 0x78, 0x7d,
        0xd5, 0xd5, 0x40, 0xec, 0x25, 0xd4, 0x3d, 0x87,
        0x20, 0x0f, 0xda, 0xdc, 0x6d, 0x1f, 0x05, 0xd9,
        0x16, 0x58, 0x4f, 0xa9, 0xf6, 0xcb, 0xf5, 0x12 }
  };
  
  static const unsigned char kwp_key[KW_TESTS][32] = {
      { 0x78, 0x65, 0xe2, 0x0f, 0x3c, 0x21, 0x65, 0x9a,
        0xb4, 0x69, 0x0b, 0x62, 0x9c, 0xdf, 0x3c, 0xc4 },
      { 0xf5, 0xf8, 0x96, 0xa3, 0xbd, 0x2f, 0x4a, 0x98,
        0x23, 0xef, 0x16, 0x2b, 0x00, 0xb8, 0x05, 0xd7,
        0xde, 0x1e, 0xa4, 0x66, 0x26, 0x96, 0xa2, 0x58 },
      { 0x95, 0xda, 0x27, 0x00, 0xca, 0x6f, 0xd9, 0xa5,
        0x25, 0x54, 0xee, 0x2a, 0x8d, 0xf1, 0x38, 0x6f,
        0x5b, 0x94, 0xa1, 0xa6, 0x0e, 0xd8, 0xa4, 0xae,
        0xf6, 0x0a, 0x8d, 0x61, 0xab, 0x5f, 0x22, 0x5a }
  };
  
  static const unsigned char kwp_msg[KW_TESTS][31] = {
      { 0xbd, 0x68, 0x43, 0xd4, 0x20, 0x37, 0x8d, 0xc8,
        0x96 },
      { 0x6c, 0xcd, 0xd5, 0x85, 0x18, 0x40, 0x97, 0xeb,
        0xd5, 0xc3, 0xaf, 0x3e, 0x47, 0xd0, 0x2c, 0x19,
        0x14, 0x7b, 0x4d, 0x99, 0x5f, 0x96, 0x43, 0x66,
        0x91, 0x56, 0x75, 0x8c, 0x13, 0x16, 0x8f },
      { 0xd1 }
  };
  static const size_t kwp_msg_len[KW_TESTS] = { 9, 31, 1 };
  
  static const unsigned char kwp_res[KW_TESTS][48] = {
      { 0x41, 0xec, 0xa9, 0x56, 0xd4, 0xaa, 0x04, 0x7e,
        0xb5, 0xcf, 0x4e, 0xfe, 0x65, 0x96, 0x61, 0xe7,
        0x4d, 0xb6, 0xf8, 0xc5, 0x64, 0xe2, 0x35, 0x00 },
      { 0x4e, 0x9b, 0xc2, 0xbc, 0xbc, 0x6c, 0x1e, 0x13,
        0xd3, 0x35, 0xbc, 0xc0, 0xf7, 0x73, 0x6a, 0x88,
        0xfa, 0x87, 0x53, 0x66, 0x15, 0xbb, 0x8e, 0x63,
        0x8b, 0xcc, 0x81, 0x66, 0x84, 0x68, 0x17, 0x90,
        0x67, 0xcf, 0xa9, 0x8a, 0x9d, 0x0e, 0x33, 0x26 },
      { 0x06, 0xba, 0x7a, 0xe6, 0xf3, 0x24, 0x8c, 0xfd,
        0xcf, 0x26, 0x75, 0x07, 0xfa, 0x00, 0x1b, 0xc4  }
  };
  static const size_t kwp_out_len[KW_TESTS] = { 24, 40, 16 };
  
  int mbedtls_nist_kw_self_test( int verbose )
  {
      mbedtls_nist_kw_context ctx;
      unsigned char out[48];
      size_t olen;
      int i;
      int ret = 0;
      mbedtls_nist_kw_init( &ctx );
  
      for( i = 0; i < KW_TESTS; i++ )
      {
          if( verbose != 0 )
              mbedtls_printf( "  KW-AES-%u ", (unsigned int) key_len[i] * 8 );
  
          ret = mbedtls_nist_kw_setkey( &ctx, MBEDTLS_CIPHER_ID_AES,
                                        kw_key[i], key_len[i] * 8, 1 );
          if( ret != 0 )
          {
              if( verbose != 0 )
                  mbedtls_printf( "  KW: setup failed " );
  
              goto end;
          }
  
          ret = mbedtls_nist_kw_wrap( &ctx, MBEDTLS_KW_MODE_KW, kw_msg[i],
                                      kw_msg_len[i], out, &olen, sizeof( out ) );
          if( ret != 0 || kw_out_len[i] != olen ||
              memcmp( out, kw_res[i], kw_out_len[i] ) != 0 )
          {
              if( verbose != 0 )
                  mbedtls_printf( "failed. ");
  
              ret = 1;
              goto end;
          }
  
          if( ( ret = mbedtls_nist_kw_setkey( &ctx, MBEDTLS_CIPHER_ID_AES,
                                              kw_key[i], key_len[i] * 8, 0 ) )
                != 0 )
          {
              if( verbose != 0 )
                  mbedtls_printf( "  KW: setup failed ");
  
              goto end;
          }
  
          ret = mbedtls_nist_kw_unwrap( &ctx, MBEDTLS_KW_MODE_KW,
                                        out, olen, out, &olen, sizeof( out ) );
  
          if( ret != 0 || olen != kw_msg_len[i] ||
              memcmp( out, kw_msg[i], kw_msg_len[i] ) != 0 )
          {
              if( verbose != 0 )
                  mbedtls_printf( "failed\n" );
  
              ret = 1;
              goto end;
          }
  
          if( verbose != 0 )
              mbedtls_printf( " passed\n" );
      }
  
      for( i = 0; i < KW_TESTS; i++ )
      {
          olen = sizeof( out );
          if( verbose != 0 )
              mbedtls_printf( "  KWP-AES-%u ", (unsigned int) key_len[i] * 8 );
  
          ret = mbedtls_nist_kw_setkey( &ctx, MBEDTLS_CIPHER_ID_AES, kwp_key[i],
                                        key_len[i] * 8, 1 );
          if( ret  != 0 )
          {
              if( verbose != 0 )
                  mbedtls_printf( "  KWP: setup failed " );
  
              goto end;
          }
          ret = mbedtls_nist_kw_wrap( &ctx, MBEDTLS_KW_MODE_KWP, kwp_msg[i],
                                      kwp_msg_len[i], out, &olen, sizeof( out ) );
  
          if( ret != 0 || kwp_out_len[i] != olen ||
              memcmp( out, kwp_res[i], kwp_out_len[i] ) != 0 )
          {
              if( verbose != 0 )
                  mbedtls_printf( "failed. ");
  
              ret = 1;
              goto end;
          }
  
          if( ( ret = mbedtls_nist_kw_setkey( &ctx, MBEDTLS_CIPHER_ID_AES,
                                              kwp_key[i], key_len[i] * 8, 0 ) )
                != 0 )
          {
              if( verbose != 0 )
                  mbedtls_printf( "  KWP: setup failed ");
  
              goto end;
          }
  
          ret = mbedtls_nist_kw_unwrap(  &ctx, MBEDTLS_KW_MODE_KWP, out,
                                         olen, out, &olen, sizeof( out ) );
  
          if( ret != 0 || olen != kwp_msg_len[i] ||
              memcmp( out, kwp_msg[i], kwp_msg_len[i] ) != 0 )
          {
              if( verbose != 0 )
                  mbedtls_printf( "failed. ");
  
              ret = 1;
              goto end;
          }
  
          if( verbose != 0 )
              mbedtls_printf( " passed\n" );
      }
  end:
      mbedtls_nist_kw_free( &ctx );
  
      if( verbose != 0 )
          mbedtls_printf( "\n" );
  
      return( ret );
  }
  
  #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
  
  #endif /* MBEDTLS_NIST_KW_C */
  