text: /*
   *  An 32-bit implementation of the XTEA algorithm
   *
   *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
   *  SPDX-License-Identifier: Apache-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.
   *
   *  This file is part of mbed TLS (https://tls.mbed.org)
   */
  
  /*
      GameSparks LLC:
          The Source files have been changed so that they can be compiled by a C++
          Compiler. This was required, because the Unreal Engine and Windows 10
          Phone / Universal Apps do not support direct compilation of C Source
          code. Also changes where made to enable the compilation from a single
          translation unit (amalgamated build).
  */
  
  #if !defined(MBEDTLS_CONFIG_FILE)
  #include "../../include/mbedtls/config.h"
  #else
  #include MBEDTLS_CONFIG_FILE
  #endif
  
  #if defined(MBEDTLS_XTEA_C)
  
  #include "../../include/mbedtls/xtea.h"
  
  #include <string.h>
  
  #if defined(MBEDTLS_SELF_TEST)
  #if defined(MBEDTLS_PLATFORM_C)
  #include "../../include/mbedtls/platform.h"
  #else
  #include <stdio.h>
  #define mbedtls_printf printf
  #endif /* MBEDTLS_PLATFORM_C */
  #endif /* MBEDTLS_SELF_TEST */
  
  #if !defined(MBEDTLS_XTEA_ALT)
  
  /* Implementation that should never be optimized out by the compiler */
  #if !defined(MBEDTLS_AMALGAMATE)
  static void mbedtls_zeroize( void *v, size_t n ) {
      volatile unsigned char *p = v; while( n-- ) *p++ = 0;
  }
  #endif /* MBEDTLS_AMALGAMATE */
  
  /*
   * 32-bit integer manipulation macros (big endian)
   */
  #ifndef GET_UINT32_BE
  #define GET_UINT32_BE(n,b,i)                            \
  {                                                       \
      (n) = ( (uint32_t) (b)[(i)    ] << 24 )             \
          | ( (uint32_t) (b)[(i) + 1] << 16 )             \
          | ( (uint32_t) (b)[(i) + 2] <<  8 )             \
          | ( (uint32_t) (b)[(i) + 3]       );            \
  }
  #endif
  
  #ifndef PUT_UINT32_BE
  #define PUT_UINT32_BE(n,b,i)                            \
  {                                                       \
      (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)       );       \
  }
  #endif
  
  void mbedtls_xtea_init( mbedtls_xtea_context *ctx )
  {
      memset( ctx, 0, sizeof( mbedtls_xtea_context ) );
  }
  
  void mbedtls_xtea_free( mbedtls_xtea_context *ctx )
  {
      if( ctx == NULL )
          return;
  
      mbedtls_zeroize( ctx, sizeof( mbedtls_xtea_context ) );
  }
  
  /*
   * XTEA key schedule
   */
  void mbedtls_xtea_setup( mbedtls_xtea_context *ctx, const unsigned char key[16] )
  {
      int i;
  
      memset( ctx, 0, sizeof(mbedtls_xtea_context) );
  
      for( i = 0; i < 4; i++ )
      {
          GET_UINT32_BE( ctx->k[i], key, i << 2 );
      }
  }
  
  /*
   * XTEA encrypt function
   */
  int mbedtls_xtea_crypt_ecb( mbedtls_xtea_context *ctx, int mode,
                      const unsigned char input[8], unsigned char output[8])
  {
      uint32_t *k, v0, v1, i;
  
      k = ctx->k;
  
      GET_UINT32_BE( v0, input, 0 );
      GET_UINT32_BE( v1, input, 4 );
  
      if( mode == MBEDTLS_XTEA_ENCRYPT )
      {
          uint32_t sum = 0, delta = 0x9E3779B9;
  
          for( i = 0; i < 32; i++ )
          {
              v0 += (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + k[sum & 3]);
              sum += delta;
              v1 += (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + k[(sum>>11) & 3]);
          }
      }
      else /* MBEDTLS_XTEA_DECRYPT */
      {
          uint32_t delta = 0x9E3779B9, sum = delta * 32;
  
          for( i = 0; i < 32; i++ )
          {
              v1 -= (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + k[(sum>>11) & 3]);
              sum -= delta;
              v0 -= (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + k[sum & 3]);
          }
      }
  
      PUT_UINT32_BE( v0, output, 0 );
      PUT_UINT32_BE( v1, output, 4 );
  
      return( 0 );
  }
  
  #if defined(MBEDTLS_CIPHER_MODE_CBC)
  /*
   * XTEA-CBC buffer encryption/decryption
   */
  int mbedtls_xtea_crypt_cbc( mbedtls_xtea_context *ctx, int mode, size_t length,
                      unsigned char iv[8], const unsigned char *input,
                      unsigned char *output)
  {
      int i;
      unsigned char temp[8];
  
      if( length % 8 )
          return( MBEDTLS_ERR_XTEA_INVALID_INPUT_LENGTH );
  
      if( mode == MBEDTLS_XTEA_DECRYPT )
      {
          while( length > 0 )
          {
              memcpy( temp, input, 8 );
              mbedtls_xtea_crypt_ecb( ctx, mode, input, output );
  
              for( i = 0; i < 8; i++ )
                  output[i] = (unsigned char)( output[i] ^ iv[i] );
  
              memcpy( iv, temp, 8 );
  
              input  += 8;
              output += 8;
              length -= 8;
          }
      }
      else
      {
          while( length > 0 )
          {
              for( i = 0; i < 8; i++ )
                  output[i] = (unsigned char)( input[i] ^ iv[i] );
  
              mbedtls_xtea_crypt_ecb( ctx, mode, output, output );
              memcpy( iv, output, 8 );
  
              input  += 8;
              output += 8;
              length -= 8;
          }
      }
  
      return( 0 );
  }
  #endif /* MBEDTLS_CIPHER_MODE_CBC */
  #endif /* !MBEDTLS_XTEA_ALT */
  
  #if defined(MBEDTLS_SELF_TEST)
  
  /*
   * XTEA tests vectors (non-official)
   */
  
  static const unsigned char xtea_test_key[6][16] =
  {
     { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
       0x0c, 0x0d, 0x0e, 0x0f },
     { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
       0x0c, 0x0d, 0x0e, 0x0f },
     { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
       0x0c, 0x0d, 0x0e, 0x0f },
     { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00 },
     { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00 },
     { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00 }
  };
  
  static const unsigned char xtea_test_pt[6][8] =
  {
      { 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48 },
      { 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 },
      { 0x5a, 0x5b, 0x6e, 0x27, 0x89, 0x48, 0xd7, 0x7f },
      { 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48 },
      { 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 },
      { 0x70, 0xe1, 0x22, 0x5d, 0x6e, 0x4e, 0x76, 0x55 }
  };
  
  static const unsigned char xtea_test_ct[6][8] =
  {
      { 0x49, 0x7d, 0xf3, 0xd0, 0x72, 0x61, 0x2c, 0xb5 },
      { 0xe7, 0x8f, 0x2d, 0x13, 0x74, 0x43, 0x41, 0xd8 },
      { 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 },
      { 0xa0, 0x39, 0x05, 0x89, 0xf8, 0xb8, 0xef, 0xa5 },
      { 0xed, 0x23, 0x37, 0x5a, 0x82, 0x1a, 0x8c, 0x2d },
      { 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 }
  };
  
  /*
   * Checkup routine
   */
  int mbedtls_xtea_self_test( int verbose )
  {
      int i, ret = 0;
      unsigned char buf[8];
      mbedtls_xtea_context ctx;
  
      mbedtls_xtea_init( &ctx );
      for( i = 0; i < 6; i++ )
      {
          if( verbose != 0 )
              mbedtls_printf( "  XTEA test #%d: ", i + 1 );
  
          memcpy( buf, xtea_test_pt[i], 8 );
  
          mbedtls_xtea_setup( &ctx, xtea_test_key[i] );
          mbedtls_xtea_crypt_ecb( &ctx, MBEDTLS_XTEA_ENCRYPT, buf, buf );
  
          if( memcmp( buf, xtea_test_ct[i], 8 ) != 0 )
          {
              if( verbose != 0 )
                  mbedtls_printf( "failed\n" );
  
              ret = 1;
              goto exit;
          }
  
          if( verbose != 0 )
              mbedtls_printf( "passed\n" );
      }
  
      if( verbose != 0 )
          mbedtls_printf( "\n" );
  
  exit:
      mbedtls_xtea_free( &ctx );
  
      return( ret );
  }
  
  #endif /* MBEDTLS_SELF_TEST */
  
  #endif /* MBEDTLS_XTEA_C */
  