plugins/squirrelspell/sqspell_functions.php

   1 <?php
   2 /**
   3  * sqspell_functions.php
   4  * ----------------------
   5  * All SquirrelSpell-wide functions are in this file.
   6  *
   7  * Copyright (c) 1999-2005 The SquirrelMail Project Team
   8  * Licensed under the GNU GPL. For full terms see the file COPYING.
   9  *
  10  * $Id$
  11  *
  12  * @author Konstantin Riabitsev <icon@duke.edu> ($Author$)
  13  * @version $Date$
  14  * @package plugins
  15  * @subpackage squirrelspell
  16  */
  17
  18 /**
  19  * This function is the GUI wrapper for the options page. SquirrelSpell
  20  * uses it for creating all Options pages.
  21  *
  22  * @param  $title     The title of the page to display
  23  * @param  $scriptsrc This is used to link a file.js into the
  24  *                    <script src="file.js"></script> format. This
  25  *                    allows to separate javascript from the rest of the
  26  *                    plugin and place it into the js/ directory.
  27  * @param  $body      The body of the message to display.
  28  * @return            void
  29  */
  30 function sqspell_makePage($title, $scriptsrc, $body){
  31   global $color, $SQSPELL_VERSION;
  32
  33   if (! sqgetGlobalVar('MOD', $MOD, SQ_GET) ) {
  34       $MOD = 'options_main';
  35   }
  36
  37   displayPageHeader($color, 'None');
  38   echo "&nbsp;<br />\n";
  39   /**
  40    * Check if we need to link in a script.
  41    */
  42   if($scriptsrc) {
  43     echo "<script type=\"text/javascript\" src=\"js/$scriptsrc\"></script>\n";
  44   }
  45   echo html_tag( 'table', '', 'center', '', 'width="95%" border="0" cellpadding="2" cellspacing="0"' ) . "\n"
  46     . html_tag( 'tr', "\n" .
  47           html_tag( 'td', '<strong>' . $title .'</strong>', 'center', $color[9] )
  48       ) . "\n"
  49     . html_tag( 'tr', "\n" .
  50           html_tag( 'td', '<hr />', 'left' )
  51       ) . "\n"
  52     . html_tag( 'tr', "\n" .
  53           html_tag( 'td', $body, 'left' )
  54       ) . "\n";
  55   /**
  56    * Generate a nice "Return to Options" link, unless this is the
  57    * starting page.
  58    */
  59   if ($MOD != "options_main"){
  60     echo html_tag( 'tr', "\n" .
  61                 html_tag( 'td', '<hr />', 'left' )
  62             ) . "\n"
  63       . html_tag( 'tr', "\n" .
  64             html_tag( 'td', '<a href="sqspell_options.php">'
  65                 . _("Back to &quot;SpellChecker Options&quot; page")
  66                 . '</a>',
  67             'center' )
  68         ) . "\n";
  69   }
  70   /**
  71    * Close the table and display the version.
  72    */
  73   echo html_tag( 'tr', "\n" .
  74               html_tag( 'td', '<hr />', 'left' )
  75           ) . "\n"
  76     . html_tag( 'tr',
  77           html_tag( 'td', 'SquirrelSpell ' . $SQSPELL_VERSION, 'center', $color[9] )
  78       ) . "\n</table>\n";
  79   echo '</body></html>';
  80 }
  81
  82 /**
  83  * Function similar to the one above. This one is a general wrapper
  84  * for the Squirrelspell pop-up window. It's called form nearly
  85  * everywhere, except the check_me module, since that one is highly
  86  * customized.
  87  *
  88  * @param  $onload    Used to indicate and pass the name of a js function
  89  *                    to call in a <body onload="function()" for automatic
  90  *                    onload script execution.
  91  * @param  $title     Title of the page.
  92  * @param  $scriptsrc If defined, link this javascript source page into
  93  *                    the document using <script src="file.js"> format.
  94  * @param  $body      The content to include.
  95  * @return            void
  96  */
  97 function sqspell_makeWindow($onload, $title, $scriptsrc, $body){
  98   global $color, $SQSPELL_VERSION;
  99
 100   displayHtmlHeader($title,
 101       ($scriptsrc ? "\n<script type=\"text/javascript\" src=\"js/$scriptsrc\"></script>\n" : ''));
 102
 103   echo "<body text=\"$color[8]\" bgcolor=\"$color[4]\" link=\"$color[7]\" "
 104       . "vlink=\"$color[7]\" alink=\"$color[7]\"";
 105   /**
 106    * Provide an onload="jsfunction()" if asked to.
 107    */
 108   if ($onload) {
 109       echo " onload=\"$onload\"";
 110   }
 111   /**
 112    * Draw the rest of the page.
 113    */
 114   echo ">\n"
 115     . html_tag( 'table', "\n" .
 116           html_tag( 'tr', "\n" .
 117               html_tag( 'td', '<strong>' . $title . '</strong>', 'center', $color[9] )
 118           ) . "\n" .
 119           html_tag( 'tr', "\n" .
 120               html_tag( 'td', '<hr />', 'left' )
 121           ) . "\n" .
 122           html_tag( 'tr', "\n" .
 123               html_tag( 'td', $body, 'left' )
 124           ) . "\n" .
 125           html_tag( 'tr', "\n" .
 126               html_tag( 'td', '<hr />', 'left' )
 127           ) . "\n" .
 128           html_tag( 'tr', "\n" .
 129               html_tag( 'td', 'SquirrelSpell ' . $SQSPELL_VERSION, 'center', $color[9] )
 130           ) ,
 131       '', '', 'width="100%" border="0" cellpadding="2"' )
 132     . "</body>\n</html>\n";
 133 }
 134
 135 /**
 136  * This function does the encryption and decryption of the user
 137  * dictionary. It is only available when PHP is compiled with
 138  * mcrypt support (--with-mcrypt). See doc/CRYPTO for more
 139  * information.
 140  *
 141  * @param  $mode  A string with either of the two recognized values:
 142  *                "encrypt" or "decrypt".
 143  * @param  $ckey  The key to use for processing (the user's password
 144  *                in our case.
 145  * @param  $input Content to decrypt or encrypt, according to $mode.
 146  * @return        encrypted/decrypted content, or "PANIC" if the
 147  *                process bails out.
 148  */
 149 function sqspell_crypto($mode, $ckey, $input){
 150   /**
 151    * Double-check if we have the mcrypt_generic function. Bail out if
 152    * not so.
 153    */
 154   if (!function_exists('mcrypt_generic')) {
 155     return 'PANIC';
 156   }
 157   /**
 158    * Setup mcrypt routines.
 159    */
 160   $td = mcrypt_module_open(MCRYPT_Blowfish, "", MCRYPT_MODE_ECB, "");
 161   $iv = mcrypt_create_iv(mcrypt_enc_get_iv_size ($td), MCRYPT_RAND);
 162   mcrypt_generic_init($td, $ckey, $iv);
 163   /**
 164    * See what we have to do depending on $mode.
 165    * 'encrypt' -- Encrypt the content.
 166    * 'decrypt' -- Decrypt the content.
 167    */
 168   switch ($mode){
 169   case 'encrypt':
 170     $crypto = mcrypt_generic($td, $input);
 171     break;
 172   case 'decrypt':
 173     $crypto = mdecrypt_generic($td, $input);
 174     /**
 175      * See if it decrypted successfully. If so, it should contain
 176      * the string "# SquirrelSpell". If not, then bail out.
 177      */
 178     if (!strstr($crypto, "# SquirrelSpell")){
 179       $crypto='PANIC';
 180     }
 181     break;
 182   }
 183   /**
 184    * Finish up the mcrypt routines and return the processed content.
 185    */
 186   if (function_exists('mcrypt_generic_deinit')) {
 187       // php 4.1.1+ syntax
 188       mcrypt_generic_deinit ($td);
 189       mcrypt_module_close ($td);
 190   } else {
 191       // older deprecated function
 192       mcrypt_generic_end ($td);
 193   }
 194   return $crypto;
 195 }
 196
 197 /**
 198  * This function transparently upgrades the 0.2 dictionary format to the
 199  * 0.3 format, since user-defined languages have been added in 0.3 and
 200  * the new format keeps user dictionaries selection in the file.
 201  *
 202  * This function will be retired soon, as it's been a while since anyone
 203  * has been using SquirrelSpell-0.2.
 204  *
 205  * @param  $words_string Contents of the 0.2-style user dictionary.
 206  * @return               Contents of the 0.3-style user dictionary.
 207  */
 208 function sqspell_upgradeWordsFile($words_string){
 209   global $SQSPELL_APP_DEFAULT, $SQSPELL_VERSION;
 210   /**
 211    * Define just one dictionary for this user -- the default.
 212    * If the user wants more, s/he can set them up in personal
 213    * preferences. See doc/UPGRADING for more info.
 214    */
 215   $new_words_string =
 216      substr_replace($words_string,
 217                     "# SquirrelSpell User Dictionary $SQSPELL_VERSION\n# "
 218                     . "Last Revision: " . date("Y-m-d")
 219                     . "\n# LANG: $SQSPELL_APP_DEFAULT\n# $SQSPELL_APP_DEFAULT",
 220                     0, strpos($words_string, "\n")) . "# End\n";
 221   sqspell_writeWords($new_words_string);
 222   return $new_words_string;
 223 }
 224
 225 /**
 226  * Right now it just returns an array with the dictionaries
 227  * available to the user for spell-checking. It will probably
 228  * do more in the future, as features are added.
 229  *
 230  * @param  $words The contents of the user's ".words" file.
 231  * @return        a strings array with dictionaries available
 232  *                to this user, e.g. {"English", "Spanish"}, etc.
 233  */
 234 function sqspell_getSettings($words){
 235   global $SQSPELL_APP, $SQSPELL_APP_DEFAULT;
 236   /**
 237    * Check if there is more than one dictionary configured in the
 238    * system config.
 239    */
 240   if (sizeof($SQSPELL_APP) > 1){
 241     /**
 242      * Now load the user prefs. Check if $words was empty -- a bit of
 243      * a dirty fall-back. TODO: make it so this is not required.
 244      */
 245     if(!$words){
 246       $words=sqspell_getWords();
 247     }
 248     if ($words){
 249       /**
 250        * This user has a ".words" file.
 251        * Find which dictionaries s/he wants to use and load them into
 252        * the $langs array.
 253        */
 254       preg_match("/# LANG: (.*)/i", $words, $matches);
 255       $langs=explode(", ", $matches[1]);
 256     } else {
 257       /**
 258        * User doesn't have a personal dictionary. Grab the default
 259        * system setting.
 260        */
 261       $langs[0]=$SQSPELL_APP_DEFAULT;
 262     }
 263   } else {
 264     /**
 265      * There is no need to read the ".words" file as there is only one
 266      * dictionary defined system-wide.
 267      */
 268     $langs[0]=$SQSPELL_APP_DEFAULT;
 269   }
 270   return $langs;
 271 }
 272
 273 /**
 274  * This function returns only user-defined dictionary words that correspond
 275  * to the requested language.
 276  *
 277  * @param  $words The contents of the user's ".words" file.
 278  * @param  $lang  Which language words to return, e.g. requesting
 279  *                "English" will return ONLY the words from user's
 280  *                English dictionary, disregarding any others.
 281  * @return        The list of words corresponding to the language
 282  *                requested.
 283  */
 284 function sqspell_getLang($words, $lang){
 285   $start=strpos($words, "# $lang\n");
 286   /**
 287    * strpos() will return -1 if no # $lang\n string was found.
 288    * Use this to return a zero-length value and indicate that no
 289    * words are present in the requested dictionary.
 290    */
 291   if (!$start) return '';
 292   /**
 293    * The words list will end with a new directive, which will start
 294    * with "#". Locate the next "#" and thus find out where the
 295    * words end.
 296    */
 297   $end=strpos($words, "#", $start+1);
 298   $lang_words = substr($words, $start, $end-$start);
 299   return $lang_words;
 300 }
 301
 302 /**
 303  * This function operates the user dictionary. If the format is
 304  * clear-text, then it just reads the file and returns it. However, if
 305  * the file is encrypted (well, "garbled"), then it tries to decrypt
 306  * it, checks whether the decryption was successful, troubleshoots if
 307  * not, then returns the clear-text dictionary to the app.
 308  *
 309  * @return the contents of the user's ".words" file, decrypted if
 310  *         necessary.
 311  */
 312 function sqspell_getWords(){
 313   global $SQSPELL_WORDS_FILE, $SQSPELL_CRYPTO;
 314   $words="";
 315   if (file_exists($SQSPELL_WORDS_FILE)){
 316     /**
 317      * Gobble it up.
 318      */
 319     $fp=fopen($SQSPELL_WORDS_FILE, 'r');
 320     $words=fread($fp, filesize($SQSPELL_WORDS_FILE));
 321     fclose($fp);
 322   }
 323   /**
 324    * Check if this is an encrypted file by looking for
 325    * the string "# SquirrelSpell" in it (the crypto
 326    * function does that).
 327    */
 328   if ($words && !strstr($words, "# SquirrelSpell")){
 329     /**
 330      * This file is encrypted or mangled. Try to decrypt it.
 331      * If fails, complain loudly.
 332      *
 333      * $old_key would be a value submitted by one of the modules with
 334      * the user's old mailbox password. I admin, this is rather dirty,
 335      * but efficient. ;)
 336      */
 337     sqgetGlobalVar('key', $key, SQ_COOKIE);
 338     sqgetGlobalVar('onetimepad', $onetimepad, SQ_SESSION);
 339
 340     sqgetGlobalVar('old_key', $old_key, SQ_POST);
 341
 342     if ($old_key != '') {
 343         $clear_key=$old_key;
 344     } else {
 345       /**
 346        * Get user's password (the key).
 347        */
 348       $clear_key = OneTimePadDecrypt($key, $onetimepad);
 349     }
 350     /**
 351      * Invoke the decryption routines.
 352      */
 353     $words=sqspell_crypto("decrypt", $clear_key, $words);
 354     /**
 355      * See if decryption failed.
 356      */
 357     if ($words=="PANIC"){
 358       /**
 359        * AAAAAAAAAAAH!!!!! OK, ok, breathe!
 360        * Let's hope the decryption failed because the user changed his
 361        * password. Bring up the option to key in the old password
 362        * or wipe the file and start over if everything else fails.
 363        *
 364        * The _("SquirrelSpell...) line has to be on one line, otherwise
 365        * gettext will bork. ;(
 366        */
 367       $msg = html_tag( 'p', "\n" .
 368                      '<strong>' . _("ATTENTION:") . '</strong><br />'
 369                      .  _("SquirrelSpell was unable to decrypt your personal dictionary. This is most likely due to the fact that you have changed your mailbox password. In order to proceed, you will have to supply your old password so that SquirrelSpell can decrypt your personal dictionary. It will be re-encrypted with your new password after this. If you haven't encrypted your dictionary, then it got mangled and is no longer valid. You will have to delete it and start anew. This is also true if you don't remember your old password -- without it, the encrypted data is no longer accessible.") ,
 370                  'left' ) .  "\n"
 371          . '<blockquote>' . "\n"
 372          . '<form method="post" onsubmit="return AYS()">' . "\n"
 373          . '<input type="hidden" name="MOD" value="crypto_badkey" />' . "\n"
 374          . html_tag( 'p',  "\n" .
 375                '<input type="checkbox" name="delete_words" value="ON" />'
 376                . _("Delete my dictionary and start a new one") . '<br />'
 377                . _("Decrypt my dictionary with my old password:")
 378                . '<input name="old_key" size="10" />' ,
 379            'left' ) . "\n"
 380          . '</blockquote>' . "\n"
 381          . html_tag( 'p', "\n" .
 382                '<input type="submit" value="'
 383                . _("Proceed") . ' &gt;&gt;" />' ,
 384            'center' ) . "\n"
 385          . '</form>' . "\n";
 386       /**
 387        * Add some string vars so they can be i18n'd.
 388        */
 389       $msg .= "<script type='text/javascript'><!--\n"
 390          . "var ui_choice = \"" . _("You must make a choice") ."\";\n"
 391          . "var ui_candel = \"" . _("You can either delete your dictionary or type in the old password. Not both.") . "\";\n"
 392          . "var ui_willdel = \"" . _("This will delete your personal dictionary file. Proceed?") . "\";\n"
 393          . "//--></script>\n";
 394       /**
 395        * See if this happened in the pop-up window or when accessing
 396        * the SpellChecker options page.
 397        * This is a dirty solution, I agree. TODO: make this prettier.
 398        */
 399       global $SCRIPT_NAME;
 400       if (strstr($SCRIPT_NAME, "sqspell_options")){
 401         sqspell_makePage(_("Error Decrypting Dictionary"),
 402                           "decrypt_error.js", $msg);
 403       } else {
 404         sqspell_makeWindow(null, _("Error Decrypting Dictionary"),
 405                            "decrypt_error.js", $msg);
 406       }
 407       exit;
 408     } else {
 409       /**
 410        * OK! Phew. Set the encryption flag to true so we can later on
 411        * encrypt it again before saving to HDD.
 412        */
 413       $SQSPELL_CRYPTO=true;
 414     }
 415   } else {
 416     /**
 417      * No encryption is/was used. Set $SQSPELL_CRYPTO to false,
 418      * in case we have to save the dictionary later.
 419      */
 420     $SQSPELL_CRYPTO=false;
 421   }
 422   /**
 423    * Check if we need to upgrade the dictionary from version 0.2.x
 424    * This is going away soon.
 425    */
 426   if (strstr($words, "Dictionary v0.2")){
 427     $words=sqspell_upgradeWordsFile($words);
 428   }
 429   return $words;
 430 }
 431
 432 /**
 433  * Writes user dictionary into the $username.words file, then changes mask
 434  * to 0600. If encryption is needed -- does that, too.
 435  *
 436  * @param  $words The contents of the ".words" file to write.
 437  * @return        void
 438  */
 439 function sqspell_writeWords($words){
 440   global $SQSPELL_WORDS_FILE, $SQSPELL_CRYPTO;
 441   /**
 442    * if $words is empty, create a template entry by calling the
 443    * sqspell_makeDummy() function.
 444    */
 445   if (!$words){
 446     $words=sqspell_makeDummy();
 447   }
 448   if ($SQSPELL_CRYPTO){
 449     /**
 450      * User wants to encrypt the file. So be it.
 451      * Get the user's password to use as a key.
 452      */
 453     sqgetGlobalVar('key', $key, SQ_COOKIE);
 454     sqgetGlobalVar('onetimepad', $onetimepad, SQ_SESSION);
 455
 456     $clear_key=OneTimePadDecrypt($key, $onetimepad);
 457     /**
 458      * Try encrypting it. If fails, scream bloody hell.
 459      */
 460     $save_words = sqspell_crypto("encrypt", $clear_key, $words);
 461     if ($save_words == 'PANIC'){
 462       /**
 463        * AAAAAAAAH! I'm not handling this yet, since obviously
 464        * the admin of the site forgot to compile the MCRYPT support in
 465        * when upgrading an existing PHP installation.
 466        * I will add a handler for this case later, when I can come up
 467        * with some work-around... Right now, do nothing. Let the Admin's
 468        * head hurt.. ;)))
 469        */
 470     }
 471   } else {
 472     $save_words = $words;
 473   }
 474   /**
 475    * Do the actual writing.
 476    */
 477   $fp=fopen($SQSPELL_WORDS_FILE, "w");
 478   fwrite($fp, $save_words);
 479   fclose($fp);
 480   chmod($SQSPELL_WORDS_FILE, 0600);
 481 }
 482
 483 function sqspell_deleteWords(){
 484   /**
 485    * So I open the door to my enemies,
 486    * and I ask can we wipe the slate clean,
 487    * but they tell me to please go...
 488    * uhm... Well, this just erases the user dictionary file.
 489    */
 490   global $SQSPELL_WORDS_FILE;
 491   if (file_exists($SQSPELL_WORDS_FILE)){
 492     unlink($SQSPELL_WORDS_FILE);
 493   }
 494 }
 495 /**
 496  * Creates an empty user dictionary for the sake of saving prefs or
 497  * whatever.
 498  *
 499  * @return The template to use when storing the user dictionary.
 500  */
 501 function sqspell_makeDummy(){
 502   global $SQSPELL_VERSION, $SQSPELL_APP_DEFAULT;
 503   $words = "# SquirrelSpell User Dictionary $SQSPELL_VERSION\n"
 504      . "# Last Revision: " . date('Y-m-d')
 505      . "\n# LANG: $SQSPELL_APP_DEFAULT\n# End\n";
 506   return $words;
 507 }
 508
 509 /**
 510  * This function checks for security attacks. A $MOD variable is
 511  * provided in the QUERY_STRING and includes one of the files from the
 512  * modules directory ($MOD.mod). See if someone is trying to get out
 513  * of the modules directory by providing dots, unicode strings, or
 514  * slashes.
 515  *
 516  * @param  $rMOD the name of the module requested to include.
 517  * @return       void, since it bails out with an access error if needed.
 518  */
 519 function sqspell_ckMOD($rMOD){
 520   if (strstr($rMOD, '.')
 521       || strstr($rMOD, '/')
 522       || strstr($rMOD, '%')
 523       || strstr($rMOD, "\\")){
 524     echo _("Cute.");
 525     exit;
 526   }
 527 }
 528
 529 /**
 530  * SquirrelSpell version. Don't modify, since it identifies the format
 531  * of the user dictionary files and messing with this can do ugly
 532  * stuff. :)
 533  */
 534 $SQSPELL_VERSION="v0.3.8";
 535 ?>