text: /*
   *  RFC 1115/1319 compliant MD2 implementation
   *
   *  Copyright (C) 2006-2014, ARM Limited, All Rights Reserved
   *
   *  This file is part of mbed TLS (https://tls.mbed.org)
   *
   *  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.
   */
  /*
   *  The MD2 algorithm was designed by Ron Rivest in 1989.
   *
   *  http://www.ietf.org/rfc/rfc1115.txt
   *  http://www.ietf.org/rfc/rfc1319.txt
   */
  
  #if !defined(MBEDTLS_CONFIG_FILE)
  #include "mbedtls/config.h"
  #else
  #include MBEDTLS_CONFIG_FILE
  #endif
  
  #if defined(MBEDTLS_MD2_C)
  
  #include "mbedtls/md2.h"
  
  #include <string.h>
  
  #if defined(MBEDTLS_SELF_TEST)
  #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 */
  
  /* Implementation that should never be optimized out by the compiler */
  static void mbedtls_zeroize( void *v, size_t n ) {
      volatile unsigned char *p = v; while( n-- ) *p++ = 0;
  }
  
  #if !defined(MBEDTLS_MD2_ALT)
  
  static const unsigned char PI_SUBST[256] =
  {
      0x29, 0x2E, 0x43, 0xC9, 0xA2, 0xD8, 0x7C, 0x01, 0x3D, 0x36,
      0x54, 0xA1, 0xEC, 0xF0, 0x06, 0x13, 0x62, 0xA7, 0x05, 0xF3,
      0xC0, 0xC7, 0x73, 0x8C, 0x98, 0x93, 0x2B, 0xD9, 0xBC, 0x4C,
      0x82, 0xCA, 0x1E, 0x9B, 0x57, 0x3C, 0xFD, 0xD4, 0xE0, 0x16,
      0x67, 0x42, 0x6F, 0x18, 0x8A, 0x17, 0xE5, 0x12, 0xBE, 0x4E,
      0xC4, 0xD6, 0xDA, 0x9E, 0xDE, 0x49, 0xA0, 0xFB, 0xF5, 0x8E,
      0xBB, 0x2F, 0xEE, 0x7A, 0xA9, 0x68, 0x79, 0x91, 0x15, 0xB2,
      0x07, 0x3F, 0x94, 0xC2, 0x10, 0x89, 0x0B, 0x22, 0x5F, 0x21,
      0x80, 0x7F, 0x5D, 0x9A, 0x5A, 0x90, 0x32, 0x27, 0x35, 0x3E,
      0xCC, 0xE7, 0xBF, 0xF7, 0x97, 0x03, 0xFF, 0x19, 0x30, 0xB3,
      0x48, 0xA5, 0xB5, 0xD1, 0xD7, 0x5E, 0x92, 0x2A, 0xAC, 0x56,
      0xAA, 0xC6, 0x4F, 0xB8, 0x38, 0xD2, 0x96, 0xA4, 0x7D, 0xB6,
      0x76, 0xFC, 0x6B, 0xE2, 0x9C, 0x74, 0x04, 0xF1, 0x45, 0x9D,
      0x70, 0x59, 0x64, 0x71, 0x87, 0x20, 0x86, 0x5B, 0xCF, 0x65,
      0xE6, 0x2D, 0xA8, 0x02, 0x1B, 0x60, 0x25, 0xAD, 0xAE, 0xB0,
      0xB9, 0xF6, 0x1C, 0x46, 0x61, 0x69, 0x34, 0x40, 0x7E, 0x0F,
      0x55, 0x47, 0xA3, 0x23, 0xDD, 0x51, 0xAF, 0x3A, 0xC3, 0x5C,
      0xF9, 0xCE, 0xBA, 0xC5, 0xEA, 0x26, 0x2C, 0x53, 0x0D, 0x6E,
      0x85, 0x28, 0x84, 0x09, 0xD3, 0xDF, 0xCD, 0xF4, 0x41, 0x81,
      0x4D, 0x52, 0x6A, 0xDC, 0x37, 0xC8, 0x6C, 0xC1, 0xAB, 0xFA,
      0x24, 0xE1, 0x7B, 0x08, 0x0C, 0xBD, 0xB1, 0x4A, 0x78, 0x88,
      0x95, 0x8B, 0xE3, 0x63, 0xE8, 0x6D, 0xE9, 0xCB, 0xD5, 0xFE,
      0x3B, 0x00, 0x1D, 0x39, 0xF2, 0xEF, 0xB7, 0x0E, 0x66, 0x58,
      0xD0, 0xE4, 0xA6, 0x77, 0x72, 0xF8, 0xEB, 0x75, 0x4B, 0x0A,
      0x31, 0x44, 0x50, 0xB4, 0x8F, 0xED, 0x1F, 0x1A, 0xDB, 0x99,
      0x8D, 0x33, 0x9F, 0x11, 0x83, 0x14
  };
  
  void mbedtls_md2_init( mbedtls_md2_context *ctx )
  {
      memset( ctx, 0, sizeof( mbedtls_md2_context ) );
  }
  
  void mbedtls_md2_free( mbedtls_md2_context *ctx )
  {
      if( ctx == NULL )
          return;
  
      mbedtls_zeroize( ctx, sizeof( mbedtls_md2_context ) );
  }
  
  void mbedtls_md2_clone( mbedtls_md2_context *dst,
                          const mbedtls_md2_context *src )
  {
      *dst = *src;
  }
  
  /*
   * MD2 context setup
   */
  void mbedtls_md2_starts( mbedtls_md2_context *ctx )
  {
      memset( ctx->cksum, 0, 16 );
      memset( ctx->state, 0, 46 );
      memset( ctx->buffer, 0, 16 );
      ctx->left = 0;
  }
  
  #if !defined(MBEDTLS_MD2_PROCESS_ALT)
  void mbedtls_md2_process( mbedtls_md2_context *ctx )
  {
      int i, j;
      unsigned char t = 0;
  
      for( i = 0; i < 16; i++ )
      {
          ctx->state[i + 16] = ctx->buffer[i];
          ctx->state[i + 32] =
              (unsigned char)( ctx->buffer[i] ^ ctx->state[i]);
      }
  
      for( i = 0; i < 18; i++ )
      {
          for( j = 0; j < 48; j++ )
          {
              ctx->state[j] = (unsigned char)
                 ( ctx->state[j] ^ PI_SUBST[t] );
              t  = ctx->state[j];
          }
  
          t = (unsigned char)( t + i );
      }
  
      t = ctx->cksum[15];
  
      for( i = 0; i < 16; i++ )
      {
          ctx->cksum[i] = (unsigned char)
             ( ctx->cksum[i] ^ PI_SUBST[ctx->buffer[i] ^ t] );
          t  = ctx->cksum[i];
      }
  }
  #endif /* !MBEDTLS_MD2_PROCESS_ALT */
  
  /*
   * MD2 process buffer
   */
  void mbedtls_md2_update( mbedtls_md2_context *ctx, const unsigned char *input, size_t ilen )
  {
      size_t fill;
  
      while( ilen > 0 )
      {
          if( ctx->left + ilen > 16 )
              fill = 16 - ctx->left;
          else
              fill = ilen;
  
          memcpy( ctx->buffer + ctx->left, input, fill );
  
          ctx->left += fill;
          input += fill;
          ilen  -= fill;
  
          if( ctx->left == 16 )
          {
              ctx->left = 0;
              mbedtls_md2_process( ctx );
          }
      }
  }
  
  /*
   * MD2 final digest
   */
  void mbedtls_md2_finish( mbedtls_md2_context *ctx, unsigned char output[16] )
  {
      size_t i;
      unsigned char x;
  
      x = (unsigned char)( 16 - ctx->left );
  
      for( i = ctx->left; i < 16; i++ )
          ctx->buffer[i] = x;
  
      mbedtls_md2_process( ctx );
  
      memcpy( ctx->buffer, ctx->cksum, 16 );
      mbedtls_md2_process( ctx );
  
      memcpy( output, ctx->state, 16 );
  }
  
  #endif /* !MBEDTLS_MD2_ALT */
  
  /*
   * output = MD2( input buffer )
   */
  void mbedtls_md2( const unsigned char *input, size_t ilen, unsigned char output[16] )
  {
      mbedtls_md2_context ctx;
  
      mbedtls_md2_init( &ctx );
      mbedtls_md2_starts( &ctx );
      mbedtls_md2_update( &ctx, input, ilen );
      mbedtls_md2_finish( &ctx, output );
      mbedtls_md2_free( &ctx );
  }
  
  #if defined(MBEDTLS_SELF_TEST)
  
  /*
   * RFC 1319 test vectors
   */
  static const char md2_test_str[7][81] =
  {
      { "" },
      { "a" },
      { "abc" },
      { "message digest" },
      { "abcdefghijklmnopqrstuvwxyz" },
      { "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789" },
      { "12345678901234567890123456789012345678901234567890123456789012" \
        "345678901234567890" }
  };
  
  static const unsigned char md2_test_sum[7][16] =
  {
      { 0x83, 0x50, 0xE5, 0xA3, 0xE2, 0x4C, 0x15, 0x3D,
        0xF2, 0x27, 0x5C, 0x9F, 0x80, 0x69, 0x27, 0x73 },
      { 0x32, 0xEC, 0x01, 0xEC, 0x4A, 0x6D, 0xAC, 0x72,
        0xC0, 0xAB, 0x96, 0xFB, 0x34, 0xC0, 0xB5, 0xD1 },
      { 0xDA, 0x85, 0x3B, 0x0D, 0x3F, 0x88, 0xD9, 0x9B,
        0x30, 0x28, 0x3A, 0x69, 0xE6, 0xDE, 0xD6, 0xBB },
      { 0xAB, 0x4F, 0x49, 0x6B, 0xFB, 0x2A, 0x53, 0x0B,
        0x21, 0x9F, 0xF3, 0x30, 0x31, 0xFE, 0x06, 0xB0 },
      { 0x4E, 0x8D, 0xDF, 0xF3, 0x65, 0x02, 0x92, 0xAB,
        0x5A, 0x41, 0x08, 0xC3, 0xAA, 0x47, 0x94, 0x0B },
      { 0xDA, 0x33, 0xDE, 0xF2, 0xA4, 0x2D, 0xF1, 0x39,
        0x75, 0x35, 0x28, 0x46, 0xC3, 0x03, 0x38, 0xCD },
      { 0xD5, 0x97, 0x6F, 0x79, 0xD8, 0x3D, 0x3A, 0x0D,
        0xC9, 0x80, 0x6C, 0x3C, 0x66, 0xF3, 0xEF, 0xD8 }
  };
  
  /*
   * Checkup routine
   */
  int mbedtls_md2_self_test( int verbose )
  {
      int i;
      unsigned char md2sum[16];
  
      for( i = 0; i < 7; i++ )
      {
          if( verbose != 0 )
              mbedtls_printf( "  MD2 test #%d: ", i + 1 );
  
          mbedtls_md2( (unsigned char *) md2_test_str[i],
               strlen( md2_test_str[i] ), md2sum );
  
          if( memcmp( md2sum, md2_test_sum[i], 16 ) != 0 )
          {
              if( verbose != 0 )
                  mbedtls_printf( "failed\n" );
  
              return( 1 );
          }
  
          if( verbose != 0 )
              mbedtls_printf( "passed\n" );
      }
  
      if( verbose != 0 )
          mbedtls_printf( "\n" );
  
      return( 0 );
  }
  
  #endif /* MBEDTLS_SELF_TEST */
  
  #endif /* MBEDTLS_MD2_C */
  