tripwire.php

<?php

/*
 *  Tripwire
 *  Luke Stevenson <www.lucanos.com>
 *
 *  This is a PHP script which will scan files within a directory (including
 *    sub-directories), calculate their MD5 Hashes and then compare them against
 *    a log of the results from the previous execution to determine any files
 *    which have been added, deleted or modified during that period.
 *
 *  Within the Configuration Settings, exclusions can be set for any files/folders
 *    which should not be checked.
 *
 *  For best results, this file should be triggered by a cron job at regular intervals.
 *    Also, be sure to add your email address to the Configuration Settings to ensure
 *    that you recieve the notifications.
 *
 */

// Check PHP Version and Die to Error if obsolete
if( !function_exists( 'version_compare' ) || version_compare( PHP_VERSION , '5.1.0' , '<' ) ){
  die( 'This script requires at least PHP v5.1.0. You are running v'.PHP_VERSION );
}

set_time_limit( 0 );

if( file_exists( 'tripwire_config.php' ) ){

 # Standalone Config File (for easy upgrading of this file)
  require_once( 'tripwire_config.php' );

}else{

 # Default Configuration
  $config = array(

    // Debugging (Verbose Output)
    'debug' => false ,

    // File Containing the MD5 Keys
    'md5file' => 'tripwire_filelist.md5' ,
    // Delimited for Filelist
    'delim' => '&&&' ,

    'exclude' => array(
      // Specific Files to Exclude from Scanning
      'files' => array(
        '.' ,
        '..' ,
        'tripwire_filelist.md5' ,
        'tripwire_config.php' ,
        'error_log' ,
        'backup.zip' ,
        '.bash_history' ,
        // Apple
        '.DS_Store' ,
        // Version control
        '.git'
      ) ,
      // Extensions to Exclude from Scanning
      'extensions' => array(
        // Adobe
        'afm' ,
        'flv' ,
        'mno' ,
        'pdf' ,
        'psd' ,
        'swf' ,
        // Images
        'bmp' ,
        'gif' ,
        'jpeg' ,
        'jpg' ,
        'png' ,
        // Text
        'log' ,
        'rdf' ,
        'txt' ,
        // Video
        'mp4' ,
        'mov' ,
        'ogv' ,
        'webm' ,
        // Audio
        'aif' ,
        'mp3' ,
        // Microsoft Files
        'doc' ,
        'docx' ,
        'ppt' ,
        'pptx' ,
        'xls' ,
        'xlsx' ,
        // Compressed Files
        '7z' ,
        'gz' ,
        'rar' ,
        'sitx' ,
        'tar' ,
        'zip'
      )
    ) ,

    'email' => array(
      'to' => array(            // Email these people on changes
        // 'user@server.com'
      ) ,
      'title' => '[Tripwire] Change Detected - [X] Files' , // The Email Title
      'body' => "Tripwire (https://github.com/lucanos/Tripwire) has detected a number of changes:\n\n[AN] Files Added:\n[AF]\n\n[MN] Files Modified:\n[MF]\n\n[DN] Files Deleted:\n[DF]\n\n"   // The Email Template
    )

  );

}



define( 'DEBUG' , isset( $config['debug'] ) && $config['debug'] );


function debugMsg( $msg = false ){
  if( DEBUG && $msg )
    echo $msg;
}


function run_tripwire( $dir=false ){
  global $config, $filelist;

  // If no Directory Specified, Default to the Root of the Site the script is executed under
  if( !$dir )
    $dir = $_SERVER['DOCUMENT_ROOT'];

  // If last character is a slash, strip it off the end
  if( substr( $dir , -1 )=='/' )
    $dir = substr( $dir , 0 , -1 );

  // If the supplied variable is not a Directory, terminate
  if( !is_dir( $dir ) ){
    debugMsg( "Directory '$dir' does not exist.\n" );
    return false;
  }
  debugMsg( "Checking directory '$dir'\n" );

  $temp = array();
  $d = dir( $dir );
  
  if($d)

  // Loop through the files
  while( false!==( $entry = $d->read() )  ){
  
    // Full Entry (including Directory)
    $entry_full = $dir.'/'.$entry;
    
    // Debugging
    debugMsg( "<tr><th align='left'>$entry_full</th>" );
      
    // Symbolic Link - Excluded
    if( @is_link( $entry ) ){
      debugMsg( "<td><em>Symbolic Link</em></td></tr>\n" );
      continue;
    }

    // Excluded File/Folder
    if( $f1 = in_array( $entry , $config['exclude']['files'] )
        || in_array( $entry_full , $config['exclude']['files'] ) ){
      debugMsg( "<td><em>Excluded File/Folder (".array_search( isset( $f1 ) && $f1 ? $entry : $entry_full , $config['exclude']['files'] ).")</em></td></tr>\n" );
      continue;
    }

    // Excluded File Extension
    if( in_array( pathinfo( $entry , PATHINFO_EXTENSION ) , $config['exclude']['extensions'] ) ){
      debugMsg( "<td><em>Excluded File Extension (".array_search( pathinfo( $entry , PATHINFO_EXTENSION ) , $config['exclude']['extensions'] ).")</em></td></tr>\n" );
      continue;
    }

    if( is_dir( $dir.'/'.$entry ) ){
      // Recurse
      debugMsg( "<td>Directory - Recursing</td></tr>\n" );
      $temp = array_merge( $temp , run_tripwire( $dir.'/'.$entry ) );
    }else{
      $md5 = @md5_file( $dir.'/'.$entry );
      debugMsg( "<td>$md5</td></tr>\n" );
      if( !$md5 ){
        debugMsg( "<td><strong>Unreadable. Adding to Unreadable List.</strong></td></tr>\n" );
        file_put_contents( 'tripwire_unreadable.txt' ,  "{$dir}/{$entry} - Unreadable\n" , FILE_APPEND );
      }else{
        $temp[$dir.'/'.$entry] = $md5;
      }
    }
  }

  if($d) $d->close();

  return $temp;

}


// In case file_put_contents does not exist
if( !function_exists( 'file_put_contents' ) ){
  function file_put_contents( $filename , $data ){
    $f = @fopen( $filename , 'w' );
    if( !$f )
      return false;
    $bytes = fwrite( $f , $data );
    fclose( $f );
    return $bytes;
  }
}


// Init the Last Check List
$last = array();


// Access the MD5 File List, if it exists
if( file_exists( $config['md5file'] ) ){
  $temp = file( $config['md5file'] , FILE_SKIP_EMPTY_LINES );

  // Split the MD5 File List into Filename and MD5 Hash
  foreach( $temp as $line ){
    list( $filename , $md5hash ) = explode( $config['delim'] , str_replace( "\n" , '' , $line ) );
    $last[$filename] = $md5hash;
  }

  unset( $temp );
}



// Format
if( DEBUG ){
?>
<pre><?php var_dump( $config['exclude'] ); ?></pre>
<table border="1" cellpadding="2" cellspacing="0">
  <thead>
    <tr>
      <th>File</th>
      <th>Result</th>
    </tr>
  </thead>
  <tbody>
<?php
}


// Init the This Check List
$now = run_tripwire( '.' );



if( DEBUG ){
?>
  </tbody>
</table>
<?php
}


// Perform Comparisons

// New Files = Files in $now, but not in $last
$new = array_diff( array_keys( $now ) , array_keys( $last ) );

// Deleted Files = Files in $last, but not in $now
$deleted = array_diff( array_keys( $last ) , array_keys( $now ) );

// Changed Files = Files in $last and $now, but with Different MD5 Hashes
$modified = array_diff_assoc( array_intersect_key( $last , $now ) , array_intersect_key( $now , $last ) );


if( DEBUG ){

  echo '<pre>';
  echo "\$new\n";
  var_dump( $new );
  echo "\$deleted\n";
  var_dump( $deleted );
  echo "\$modified\n";
  var_dump( $modified );
  echo '</pre>';

}


if( !count( $last ) // If there was no file list
    || ( count( $new ) || count( $deleted ) || count( $modified ) ) ){ // Or a change was detected

  # Update the file list

  // Init an Array for Lines
  $log = array();

  // Compress the MD5 Hash Array into lines
  foreach( $now as $k => $v )
    $log[] = "{$k}{$config['delim']}{$v}";

  // Write to the File List
  file_put_contents( $config['md5file'] , implode( "\n" , $log ) );

}



// If there was a Filelist from the last run to compare against, and changes have occurred

  # Changes Detected

// Prepare Report

if( count( $last )
    && ( count( $new ) || count( $deleted ) || count( $modified ) ) ){
  # Changes Detected

  // Prepare the placeholder details
  $body_replacements = array(
    '[AN]' => count( $new ) ,
    '[AF]' => ( count( $new ) ? implode( "\n" , $new ) : 'No Files' ) ,
    '[MN]' => count( $modified ) ,
    '[MF]' => ( count( $modified ) ? implode( "\n" , array_keys( $modified ) ) : 'No Files' ) ,
    '[DN]' => count( $deleted ) ,
    '[DF]' => ( count( $deleted ) ? implode( "\n" , $deleted ) : 'No Files' ) ,
  );
  $title = str_replace( '[X]' , ( count( $new )+count( $deleted )+count( $modified ) ) , $config['email']['title'] );
  
  // Send Email Flag
  $sendEmail = true;

}elseif( count( $last ) ){
 # No Changes Detected

  // Prepare the placeholder details
  $body_replacements = array(
    '[AN]' => 0 ,
    '[AF]' => 'No Files' ,
    '[MN]' => 0 ,
    '[MF]' => 'No Files' ,
    '[DN]' => 0 ,
    '[DF]' => 'No Files' ,
  );
  $title = str_replace( '[X]' , 0 , $config['email']['title'] );
  
  // Send Email Flag
  $sendEmail = false;

}else{
 # First Run

  // Prepare the placeholder details
  $body_replacements = array(
    '[AN]' => count( $new ) ,
    '[AF]' => ( count( $new ) ? implode( "\n" , $new ) : 'No Files' ) ,
    '[MN]' => 0 ,
    '[MF]' => 'No Files' ,
    '[DN]' => 0 ,
    '[DF]' => 'No Files' ,
  );
  $title = str_replace( '[X]' , count( $new ) , $config['email']['title'] );
  
  // Adjust the Template
  $config['email']['body'] = "Tripwire has made it's first pass of your files.\n\n".$config['email']['body'];
  
  // Send Email Flag
  $sendEmail = true;

}


// Perform the Placeholder Substitutions within the Body
$body = str_replace(
          array_keys( $body_replacements ) ,
          $body_replacements ,
          $config['email']['body']
        );


if( count( $config['email']['to'] ) ){

  if( $sendEmail ){

    // Prepare the recipients
    $to = implode( ', ' , $config['email']['to'] );
    // Send it
    if( mail( $to , $title , $body ) ){
      echo "Email Sent Successfully\n";
    }else{
      echo "Email Failed\n";
    }
    
  }else{
  
    // No Email Needed
  
  }
  
}else{
  // Just echo the result
  echo '<pre>'.$body.'</pre>';
}