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) 1999-2002 The SquirrelMail development 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  */
  15
  16 /**
  17  * This function is the GUI wrapper for the options page. SquirrelSpell
  18  * uses it for creating all Options pages.
  19  *
  20  * @param  $title     The title of the page to display
  21  * @param  $scriptsrc This is used to link a file.js into the
  22  *                    <script src="file.js"></script> format. This
  23  *                    allows to separate javascript from the rest of the
  24  *                    plugin and place it into the js/ directory.
  25  * @param  $body      The body of the message to display.
  26  * @return            void
  27  */
  28 function sqspell_makePage($title, $scriptsrc, $body){
  29   global $color, $SQSPELL_VERSION, $MOD;
  30   displayPageHeader($color, 'None');
  31   echo "&nbsp;<br>\n";
  32   /**
  33    * Check if we need to link in a script.
  34    */
  35   if($scriptsrc) {
  36     echo "<script type=\"text/javascript\" src=\"js/$scriptsrc\"></script>\n";
  37   }
  38   echo '<table width="95%" align="center" border="0" cellpadding="2" '
  39     . 'cellspacing="0">'
  40     . '<tr>'
  41     . "<td bgcolor=\"$color[9]\" align=center>"
  42     . "<strong>$title</strong>"
  43     . '</td>'
  44     . '</tr>'
  45     . '<tr><td><hr></td></tr>'
  46     . "<tr><td>$body</td></tr>";
  47   /**
  48    * Generate a nice "Return to Options" link, unless this is the
  49    * starting page.
  50    */
  51   if ($MOD != "options_main"){
  52     echo '<tr><td><hr></td></tr>'
  53       . '<tr><td align="center"><a href="sqspell_options.php">'
  54       . _("Back to &quot;SpellChecker Options&quot; page")
  55       . '</a></td></tr>';
  56   }
  57   /**
  58    * Close the table and display the version.
  59    */
  60   echo '<tr><td><hr></td></tr>'
  61     . '<tr>'
  62     . "<td bgcolor=\"$color[9]\" align=center>"
  63     . "SquirrelSpell $SQSPELL_VERSION"
  64     . '</td>'
  65     . '</tr>'
  66     . '</table>';
  67 }
  68
  69 /**
  70  * Function similar to the one above. This one is a general wrapper
  71  * for the Squirrelspell pop-up window. It's called form nearly
  72  * everywhere, except the check_me module, since that one is highly
  73  * customized.
  74  *
  75  * @param  $onload    Used to indicate and pass the name of a js function
  76  *                    to call in a <body onload="function()" for automatic
  77  *                    onload script execution.
  78  * @param  $title     Title of the page.
  79  * @param  $scriptsrc If defined, link this javascript source page into
  80  *                    the document using <script src="file.js"> format.
  81  * @param  $body      The content to include.
  82  * @return            void
  83  */
  84 function sqspell_makeWindow($onload, $title, $scriptsrc, $body){
  85   global $color, $SQSPELL_VERSION, $theme_css;
  86   echo "<html>\n"
  87     . "<head>\n"
  88     . "<title>$title</title>\n";
  89   /**
  90    * Check if we have a defined css theme to use.
  91    */
  92   if ($theme_css != "") {
  93     echo "<LINK REL=\"stylesheet\" TYPE=\"text/css\" HREF=\"$theme_css\">\n";
  94   }
  95   /**
  96    * Link in the .js file if needed
  97    */
  98   if ($scriptsrc){
  99     echo "<script type=\"text/javascript\" src=\"js/$scriptsrc\"></script>\n";
 100   }
 101   echo "</head>\n"
 102     . "<body text=\"$color[8]\" bgcolor=\"$color[4]\" link=\"$color[7]\" "
 103     . "vlink=\"$color[7]\" alink=\"$color[7]\"";
 104   /**
 105    * Provide an onload="jsfunction()" if asked to.
 106    */
 107   if ($onload) {
 108     echo " onload=\"$onload\"";
 109   }
 110   /**
 111    * Draw the rest of the page.
 112    */
 113   echo '>'
 114     . '<table width="100%" border="0" cellpadding="2">'
 115     . '<tr>'
 116     . "<td bgcolor=\"$color[9]\" align=center>"
 117     . "<strong>$title</strong>"
 118     . '</td>'
 119     . '</tr>'
 120     . '<tr><td><hr></td></tr>'
 121     . '<tr>'
 122     . "<td>$body</td>"
 123     . '</tr>'
 124     . '<tr><td><hr></td></tr>'
 125     . '<tr>'
 126     . "<td bgcolor=\"$color[9]\" align=center>"
 127     . "SquirrelSpell $SQSPELL_VERSION"
 128     . '</td>'
 129     . '</tr>'
 130     . '</table>'
 131     . "</body>\n</html>\n";
 132 }
 133
 134 /**
 135  * This function does the encryption and decryption of the user
 136  * dictionary. It is only available when PHP is compiled with
 137  * mcrypt support (--with-mcrypt). See doc/CRYPTO for more
 138  * information.
 139  *
 140  * @param  $mode  A string with either of the two recognized values:
 141  *                "encrypt" or "decrypt".
 142  * @param  $ckey  The key to use for processing (the user's password
 143  *                in our case.
 144  * @param  $input Content to decrypt or encrypt, according to $mode.
 145  * @return        encrypted/decrypted content, or "PANIC" if the
 146  *                process bails out.
 147  */
 148 function sqspell_crypto($mode, $ckey, $input){
 149   /**
 150    * Double-check if we have the mcrypt_generic function. Bail out if
 151    * not so.
 152    */
 153   if (!function_exists(mcrypt_generic)) {
 154     return 'PANIC';
 155   }
 156   /**
 157    * Setup mcrypt routines.
 158    */
 159   $td = mcrypt_module_open(MCRYPT_Blowfish, "", MCRYPT_MODE_ECB, "");
 160   $iv = mcrypt_create_iv(mcrypt_enc_get_iv_size ($td), MCRYPT_RAND);
 161   mcrypt_generic_init($td, $ckey, $iv);
 162   /**
 163    * See what we have to do depending on $mode.
 164    * 'encrypt' -- Encrypt the content.
 165    * 'decrypt' -- Decrypt the content.
 166    */
 167   switch ($mode){
 168   case 'encrypt':
 169     $crypto = mcrypt_generic($td, $input);
 170     break;
 171   case 'decrypt':
 172     $crypto = mdecrypt_generic($td, $input);
 173     /**
 174      * See if it decrypted successfully. If so, it should contain
 175      * the string "# SquirrelSpell". If not, then bail out.
 176      */
 177     if (!strstr($crypto, "# SquirrelSpell")){
 178       $crypto='PANIC';
 179     }
 180     break;
 181   }
 182   /**
 183    * Finish up the mcrypt routines and return the processed content.
 184    */
 185   mcrypt_generic_end ($td);
 186   return $crypto;
 187 }
 188
 189 /**
 190  * This function transparently upgrades the 0.2 dictionary format to the
 191  * 0.3 format, since user-defined languages have been added in 0.3 and
 192  * the new format keeps user dictionaries selection in the file.
 193  *
 194  * This function will be retired soon, as it's been a while since anyone
 195  * has been using SquirrelSpell-0.2.
 196  *
 197  * @param  $words_string Contents of the 0.2-style user dictionary.
 198  * @return               Contents of the 0.3-style user dictionary.
 199  */
 200 function sqspell_upgradeWordsFile($words_string){
 201   global $SQSPELL_APP_DEFAULT, $SQSPELL_VERSION;
 202   /**
 203    * Define just one dictionary for this user -- the default.
 204    * If the user wants more, s/he can set them up in personal
 205    * preferences. See doc/UPGRADING for more info.
 206    */
 207   $new_words_string =
 208      substr_replace($words_string,
 209                     "# SquirrelSpell User Dictionary $SQSPELL_VERSION\n# "
 210                     . "Last Revision: " . date("Y-m-d")
 211                     . "\n# LANG: $SQSPELL_APP_DEFAULT\n# $SQSPELL_APP_DEFAULT",
 212                     0, strpos($words_string, "\n")) . "# End\n";
 213   sqspell_writeWords($new_words_string);
 214   return $new_words_string;
 215 }
 216
 217 /**
 218  * Right now it just returns an array with the dictionaries
 219  * available to the user for spell-checking. It will probably
 220  * do more in the future, as features are added.
 221  *
 222  * @param  $words The contents of the user's ".words" file.
 223  * @return        a strings array with dictionaries available
 224  *                to this user, e.g. {"English", "Spanish"}, etc.
 225  */
 226 function sqspell_getSettings($words){
 227   global $SQSPELL_APP, $SQSPELL_APP_DEFAULT;
 228   /**
 229    * Check if there is more than one dictionary configured in the
 230    * system config.
 231    */
 232   if (sizeof($SQSPELL_APP) > 1){
 233     /**
 234      * Now load the user prefs. Check if $words was empty -- a bit of
 235      * a dirty fall-back. TODO: make it so this is not required.
 236      */
 237     if(!$words){
 238       $words=sqspell_getWords();
 239     }
 240     if ($words){
 241       /**
 242        * This user has a ".words" file.
 243        * Find which dictionaries s/he wants to use and load them into
 244        * the $langs array.
 245        */
 246       preg_match("/# LANG: (.*)/i", $words, $matches);
 247       $langs=explode(", ", $matches[1]);
 248     } else {
 249       /**
 250        * User doesn't have a personal dictionary. Grab the default
 251        * system setting.
 252        */
 253       $langs[0]=$SQSPELL_APP_DEFAULT;
 254     }
 255   } else {
 256     /**
 257      * There is no need to read the ".words" file as there is only one
 258      * dictionary defined system-wide.
 259      */
 260     $langs[0]=$SQSPELL_APP_DEFAULT;
 261   }
 262   return $langs;
 263 }
 264
 265 /**
 266  * This function returns only user-defined dictionary words that correspond
 267  * to the requested language.
 268  *
 269  * @param  $words The contents of the user's ".words" file.
 270  * @param  $lang  Which language words to return, e.g. requesting
 271  *                "English" will return ONLY the words from user's
 272  *                English dictionary, disregarding any others.
 273  * @return        The list of words corresponding to the language
 274  *                requested.
 275  */
 276 function sqspell_getLang($words, $lang){
 277   $start=strpos($words, "# $lang\n");
 278   /**
 279    * strpos() will return -1 if no # $lang\n string was found.
 280    * Use this to return a zero-length value and indicate that no
 281    * words are present in the requested dictionary.
 282    */
 283   if (!$start) return '';
 284   /**
 285    * The words list will end with a new directive, which will start
 286    * with "#". Locate the next "#" and thus find out where the
 287    * words end.
 288    */
 289   $end=strpos($words, "#", $start+1);
 290   $lang_words = substr($words, $start, $end-$start);
 291   return $lang_words;
 292 }
 293
 294 /**
 295  * This function operates the user dictionary. If the format is
 296  * clear-text, then it just reads the file and returns it. However, if
 297  * the file is encrypted (well, "garbled"), then it tries to decrypt
 298  * it, checks whether the decryption was successful, troubleshoots if
 299  * not, then returns the clear-text dictionary to the app.
 300  *
 301  * @return the contents of the user's ".words" file, decrypted if
 302  *         necessary.
 303  */
 304 function sqspell_getWords(){
 305   global $SQSPELL_WORDS_FILE, $SQSPELL_CRYPTO;
 306   $words="";
 307   if (file_exists($SQSPELL_WORDS_FILE)){
 308     /**
 309      * Gobble it up.
 310      */
 311     $fp=fopen($SQSPELL_WORDS_FILE, 'r');
 312     $words=fread($fp, filesize($SQSPELL_WORDS_FILE));
 313     fclose($fp);
 314   }
 315   /**
 316    * Check if this is an encrypted file by looking for
 317    * the string "# SquirrelSpell" in it (the crypto
 318    * function does that).
 319    */
 320   if ($words && !strstr($words, "# SquirrelSpell")){
 321     /**
 322      * This file is encrypted or mangled. Try to decrypt it.
 323      * If fails, complain loudly.
 324      *
 325      * $old_key would be a value submitted by one of the modules with
 326      * the user's old mailbox password. I admin, this is rather dirty,
 327      * but efficient. ;)
 328      */
 329     global $key, $onetimepad, $old_key;
 330     if ($old_key) {
 331       $clear_key=$old_key;
 332     } else {
 333       /**
 334        * Get user's password (the key).
 335        */
 336       $clear_key = OneTimePadDecrypt($key, $onetimepad);
 337     }
 338     /**
 339      * Invoke the decryption routines.
 340      */
 341     $words=sqspell_crypto("decrypt", $clear_key, $words);
 342     /**
 343      * See if decryption failed.
 344      */
 345     if ($words=="PANIC"){
 346       /**
 347        * AAAAAAAAAAAH!!!!! OK, ok, breathe!
 348        * Let's hope the decryption failed because the user changed his
 349        * password. Bring up the option to key in the old password
 350        * or wipe the file and start over if everything else fails.
 351        *
 352        * The _("SquirrelSpell...) line has to be on one line, otherwise
 353        * gettext will bork. ;(
 354        */
 355       $msg='<p>'
 356          . '<strong>' . _("ATTENTION:") . '</strong><br>'
 357          .  _("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.<br>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.")
 358          . '</p>'
 359          . '<blockquote>'
 360          . '<form method="post" onsubmit="return AYS()">'
 361          . '<input type="hidden" name="MOD" value="crypto_badkey">'
 362          . '<p><input type="checkbox" name="delete_words" value="ON">'
 363          . _("Delete my dictionary and start a new one") . '<br>'
 364          . _("Decrypt my dictionary with my old password:")
 365          . '<input name="old_key" size=\"10\"></p>'
 366          . '</blockquote>'
 367          . '<p align="center"><input type="submit" value="'
 368          . _("Proceed") . ' &gt;&gt;"></p>'
 369          . '</form>';
 370       /**
 371        * See if this happened in the pop-up window or when accessing
 372        * the SpellChecker options page.
 373        * This is a dirty solution, I agree. TODO: make this prettier.
 374        */
 375       global $SCRIPT_NAME;
 376       if (strstr($SCRIPT_NAME, "sqspell_options")){
 377         sqspell_makePage( _("Error Decrypting Dictionary"),
 378                           "decrypt_error.js", $msg);
 379       } else {
 380         sqspell_makeWindow(null, _("Error Decrypting Dictionary"),
 381                            "decrypt_error.js", $msg);
 382       }
 383       exit;
 384     } else {
 385       /**
 386        * OK! Phew. Set the encryption flag to true so we can later on
 387        * encrypt it again before saving to HDD.
 388        */
 389       $SQSPELL_CRYPTO=true;
 390     }
 391   } else {
 392     /**
 393      * No encryption is/was used. Set $SQSPELL_CRYPTO to false,
 394      * in case we have to save the dictionary later.
 395      */
 396     $SQSPELL_CRYPTO=false;
 397   }
 398   /**
 399    * Check if we need to upgrade the dictionary from version 0.2.x
 400    * This is going away soon.
 401    */
 402   if (strstr($words, "Dictionary v0.2")){
 403     $words=sqspell_upgradeWordsFile($words);
 404   }
 405   return $words;
 406 }
 407
 408 /**
 409  * Writes user dictionary into the $username.words file, then changes mask
 410  * to 0600. If encryption is needed -- does that, too.
 411  *
 412  * @param  $words The contents of the ".words" file to write.
 413  * @return        void
 414  */
 415 function sqspell_writeWords($words){
 416   global $SQSPELL_WORDS_FILE, $SQSPELL_CRYPTO;
 417   /**
 418    * if $words is empty, create a template entry by calling the
 419    * sqspell_makeDummy() function.
 420    */
 421   if (!$words){
 422     $words=sqspell_makeDummy();
 423   }
 424   if ($SQSPELL_CRYPTO){
 425     /**
 426      * User wants to encrypt the file. So be it.
 427      * Get the user's password to use as a key.
 428      */
 429     global $key, $onetimepad;
 430     $clear_key=OneTimePadDecrypt($key, $onetimepad);
 431     /**
 432      * Try encrypting it. If fails, scream bloody hell.
 433      */
 434     $save_words = sqspell_crypto("encrypt", $clear_key, $words);
 435     if ($save_words == 'PANIC'){
 436       /**
 437        * AAAAAAAAH! I'm not handling this yet, since obviously
 438        * the admin of the site forgot to compile the MCRYPT support in
 439        * when upgrading an existing PHP installation.
 440        * I will add a handler for this case later, when I can come up
 441        * with some work-around... Right now, do nothing. Let the Admin's
 442        * head hurt.. ;)))
 443        */
 444     }
 445   } else {
 446     $save_words = $words;
 447   }
 448   /**
 449    * Do the actual writing.
 450    */
 451   $fp=fopen($SQSPELL_WORDS_FILE, "w");
 452   fwrite($fp, $save_words);
 453   fclose($fp);
 454   chmod($SQSPELL_WORDS_FILE, 0600);
 455 }
 456
 457 function sqspell_deleteWords(){
 458   /**
 459    * So I open the door to my enemies,
 460    * and I ask can we wipe the slate clean,
 461    * but they tell me to please go...
 462    * uhm... Well, this just erases the user dictionary file.
 463    */
 464   global $SQSPELL_WORDS_FILE;
 465   if (file_exists($SQSPELL_WORDS_FILE)){
 466     unlink($SQSPELL_WORDS_FILE);
 467   }
 468 }
 469 /**
 470  * Creates an empty user dictionary for the sake of saving prefs or
 471  * whatever.
 472  *
 473  * @return The template to use when storing the user dictionary.
 474  */
 475 function sqspell_makeDummy(){
 476   global $SQSPELL_VERSION, $SQSPELL_APP_DEFAULT;
 477   $words = "# SquirrelSpell User Dictionary $SQSPELL_VERSION\n"
 478      . "# Last Revision: " . date('Y-m-d')
 479      . "\n# LANG: $SQSPELL_APP_DEFAULT\n# End\n";
 480   return $words;
 481 }
 482
 483 /**
 484  * This function checks for security attacks. A $MOD variable is
 485  * provided in the QUERY_STRING and includes one of the files from the
 486  * modules directory ($MOD.mod). See if someone is trying to get out
 487  * of the modules directory by providing dots, unicode strings, or
 488  * slashes.
 489  *
 490  * @param  $rMOD the name of the module requested to include.
 491  * @return       void, since it bails out with an access error if needed.
 492  */
 493 function sqspell_ckMOD($rMOD){
 494   if (strstr($rMOD, '.')
 495       || strstr($rMOD, '/')
 496       || strstr($rMOD, '%')
 497       || strstr($rMOD, "\\")){
 498     echo _("Cute.");
 499     exit;
 500   }
 501 }
 502
 503 /**
 504  * SquirrelSpell version. Don't modify, since it identifies the format
 505  * of the user dictionary files and messing with this can do ugly
 506  * stuff. :)
 507  */
 508 $SQSPELL_VERSION="v0.3.7";
 509 ?>