text: /*
   *  generic message digest layer demonstration program
   *
   *  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)
   */
  
  #if !defined(MBEDTLS_CONFIG_FILE)
  #include "mbedtls/config.h"
  #else
  #include MBEDTLS_CONFIG_FILE
  #endif
  
  #if defined(MBEDTLS_PLATFORM_C)
  #include "mbedtls/platform.h"
  #else
  #include <stdio.h>
  #include <stdlib.h>
  #define mbedtls_fprintf         fprintf
  #define mbedtls_printf          printf
  #define mbedtls_exit            exit
  #define MBEDTLS_EXIT_SUCCESS    EXIT_SUCCESS
  #define MBEDTLS_EXIT_FAILURE    EXIT_FAILURE
  #endif /* MBEDTLS_PLATFORM_C */
  
  #if defined(MBEDTLS_MD_C) && defined(MBEDTLS_FS_IO)
  #include "mbedtls/md.h"
  
  #include <stdio.h>
  #include <string.h>
  #endif
  
  #if !defined(MBEDTLS_MD_C) || !defined(MBEDTLS_FS_IO)
  int main( void )
  {
      mbedtls_printf("MBEDTLS_MD_C and/or MBEDTLS_FS_IO not defined.\n");
      return( 0 );
  }
  #else
  
  
  static int generic_wrapper( const mbedtls_md_info_t *md_info, char *filename, unsigned char *sum )
  {
      int ret = mbedtls_md_file( md_info, filename, sum );
  
      if( ret == 1 )
          mbedtls_fprintf( stderr, "failed to open: %s\n", filename );
  
      if( ret == 2 )
          mbedtls_fprintf( stderr, "failed to read: %s\n", filename );
  
      return( ret );
  }
  
  static int generic_print( const mbedtls_md_info_t *md_info, char *filename )
  {
      int i;
      unsigned char sum[MBEDTLS_MD_MAX_SIZE];
  
      if( generic_wrapper( md_info, filename, sum ) != 0 )
          return( 1 );
  
      for( i = 0; i < mbedtls_md_get_size( md_info ); i++ )
          mbedtls_printf( "%02x", sum[i] );
  
      mbedtls_printf( "  %s\n", filename );
      return( 0 );
  }
  
  static int generic_check( const mbedtls_md_info_t *md_info, char *filename )
  {
      int i;
      size_t n;
      FILE *f;
      int nb_err1, nb_err2;
      int nb_tot1, nb_tot2;
      unsigned char sum[MBEDTLS_MD_MAX_SIZE];
      char line[1024];
      char diff;
  #if defined(__clang_analyzer__)
      char buf[MBEDTLS_MD_MAX_SIZE * 2 + 1] = { };
  #else
      char buf[MBEDTLS_MD_MAX_SIZE * 2 + 1];
  #endif
  
      if( ( f = fopen( filename, "rb" ) ) == NULL )
      {
          mbedtls_printf( "failed to open: %s\n", filename );
          return( 1 );
      }
  
      nb_err1 = nb_err2 = 0;
      nb_tot1 = nb_tot2 = 0;
  
      memset( line, 0, sizeof( line ) );
  
      n = sizeof( line );
  
      while( fgets( line, (int) n - 1, f ) != NULL )
      {
          n = strlen( line );
  
          if( n < (size_t) 2 * mbedtls_md_get_size( md_info ) + 4 )
          {
              mbedtls_printf("No '%s' hash found on line.\n", mbedtls_md_get_name( md_info ));
              continue;
          }
  
          if( line[2 * mbedtls_md_get_size( md_info )] != ' ' || line[2 * mbedtls_md_get_size( md_info ) + 1] != ' ' )
          {
              mbedtls_printf("No '%s' hash found on line.\n", mbedtls_md_get_name( md_info ));
              continue;
          }
  
          if( line[n - 1] == '\n' ) { n--; line[n] = '\0'; }
          if( line[n - 1] == '\r' ) { n--; line[n] = '\0'; }
  
          nb_tot1++;
  
          if( generic_wrapper( md_info, line + 2 + 2 * mbedtls_md_get_size( md_info ), sum ) != 0 )
          {
              nb_err1++;
              continue;
          }
  
          nb_tot2++;
  
          for( i = 0; i < mbedtls_md_get_size( md_info ); i++ )
              sprintf( buf + i * 2, "%02x", sum[i] );
  
          /* Use constant-time buffer comparison */
          diff = 0;
          for( i = 0; i < 2 * mbedtls_md_get_size( md_info ); i++ )
              diff |= line[i] ^ buf[i];
  
          if( diff != 0 )
          {
              nb_err2++;
              mbedtls_fprintf( stderr, "wrong checksum: %s\n", line + 66 );
          }
  
          n = sizeof( line );
      }
  
      if( nb_err1 != 0 )
      {
          mbedtls_printf( "WARNING: %d (out of %d) input files could "
                  "not be read\n", nb_err1, nb_tot1 );
      }
  
      if( nb_err2 != 0 )
      {
          mbedtls_printf( "WARNING: %d (out of %d) computed checksums did "
                  "not match\n", nb_err2, nb_tot2 );
      }
  
      fclose( f );
  
      return( nb_err1 != 0 || nb_err2 != 0 );
  }
  
  int main( int argc, char *argv[] )
  {
      int ret = 1, i;
      int exit_code = MBEDTLS_EXIT_FAILURE;
      const mbedtls_md_info_t *md_info;
      mbedtls_md_context_t md_ctx;
  
      mbedtls_md_init( &md_ctx );
  
      if( argc == 1 )
      {
          const int *list;
  
          mbedtls_printf( "print mode:  generic_sum <mbedtls_md> <file> <file> ...\n" );
          mbedtls_printf( "check mode:  generic_sum <mbedtls_md> -c <checksum file>\n" );
  
          mbedtls_printf( "\nAvailable message digests:\n" );
          list = mbedtls_md_list();
          while( *list )
          {
              md_info = mbedtls_md_info_from_type( *list );
              mbedtls_printf( "  %s\n", mbedtls_md_get_name( md_info ) );
              list++;
          }
  
  #if defined(_WIN32)
          mbedtls_printf( "\n  Press Enter to exit this program.\n" );
          fflush( stdout ); getchar();
  #endif
  
          return( exit_code );
      }
  
      /*
       * Read the MD from the command line
       */
      md_info = mbedtls_md_info_from_string( argv[1] );
      if( md_info == NULL )
      {
          mbedtls_fprintf( stderr, "Message Digest '%s' not found\n", argv[1] );
          return( exit_code );
      }
      if( mbedtls_md_setup( &md_ctx, md_info, 0 ) )
      {
          mbedtls_fprintf( stderr, "Failed to initialize context.\n" );
          return( exit_code );
      }
  
      ret = 0;
      if( argc == 4 && strcmp( "-c", argv[2] ) == 0 )
      {
          ret |= generic_check( md_info, argv[3] );
          goto exit;
      }
  
      for( i = 2; i < argc; i++ )
          ret |= generic_print( md_info, argv[i] );
  
      if ( ret == 0 )
          exit_code = MBEDTLS_EXIT_SUCCESS;
  
  exit:
      mbedtls_md_free( &md_ctx );
  
      return( exit_code );
  }
  #endif /* MBEDTLS_MD_C && MBEDTLS_FS_IO */
  