lib/validateurlsyntax.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /**
  19  * About validateUrlSyntax():
  20  * This function will verify if a http URL is formatted properly, returning
  21  * either with true or false.
  22  *
  23  * I used rfc #2396 URI: Generic Syntax as my guide when creating the
  24  * regular expression. For all the details see the comments below.
  25  *
  26  * Usage:
  27  *     validateUrlSyntax( url_to_check[, options])
  28  *
  29  *     url_to_check - string - The url to check
  30  *
  31  *     options - string - A optional string of options to set which parts of
  32  *          the url are required, optional, or not allowed. Each option
  33  *          must be followed by a "+" for required, "?" for optional, or
  34  *          "-" for not allowed.
  35  *
  36  *          s - Scheme. Allows "+?-", defaults to "s?"
  37  *              H - http:// Allows "+?-", defaults to "H?"
  38  *              S - https:// (SSL). Allows "+?-", defaults to "S?"
  39  *              E - mailto: (email). Allows "+?-", defaults to "E-"
  40  *              F - ftp:// Allows "+?-", defaults to "F-"
  41  *                  Dependant on scheme being enabled
  42  *          u - User section. Allows "+?-", defaults to "u?"
  43  *              P - Password in user section. Allows "+?-", defaults to "P?"
  44  *                  Dependant on user section being enabled
  45  *          a - Address (ip or domain). Allows "+?-", defaults to "a+"
  46  *              I - Ip address. Allows "+?-", defaults to "I?"
  47  *                  If I+, then domains are disabled
  48  *                  If I-, then domains are required
  49  *                  Dependant on address being enabled
  50  *          p - Port number. Allows "+?-", defaults to "p?"
  51  *          f - File path. Allows "+?-", defaults to "f?"
  52  *          q - Query section. Allows "+?-", defaults to "q?"
  53  *          r - Fragment (anchor). Allows "+?-", defaults to "r?"
  54  *
  55  *  Paste the funtion code, or include_once() this template at the top of the page
  56  *  you wish to use this function.
  57  *
  58  *
  59  * Examples:
  60  * <code>
  61  *  validateUrlSyntax('http://george@www.cnn.com/#top')
  62  *
  63  *  validateUrlSyntax('https://games.yahoo.com:8080/board/chess.htm?move=true')
  64  *
  65  *  validateUrlSyntax('http://www.hotmail.com/', 's+u-I-p-q-r-')
  66  *
  67  *  validateUrlSyntax('/directory/file.php#top', 's-u-a-p-f+')
  68  *
  69  *
  70  *  if (validateUrlSyntax('http://www.canowhoopass.com/', 'u-'))
  71  *  {
  72  *      echo 'URL SYNTAX IS VERIFIED';
  73  *  } else {
  74  *      echo 'URL SYNTAX IS ILLEGAL';
  75  *  }
  76  * </code>
  77  *
  78  * Last Edited:
  79  *  June 15th 2017
  80  *
  81  *
  82  * Changelog:
  83  *  June 15th 2017 by Moodle.
  84  *    -Added rtmp:// option.
  85  *
  86  *  December 15th 2004
  87  *    -Added new TLD's - .jobs, .mobi, .post and .travel. They are official, but not yet active.
  88  *
  89  *  August 31th 2004
  90  *    -Fixed bug allowing empty username even when it was required
  91  *    -Changed and added a few options to add extra schemes
  92  *    -Added mailto: ftp:// and http:// options
  93  *    -https option was 'l' now it is 'S' (capital)
  94  *    -Added password option. Now passwords can be disabled while usernames are ok (for email)
  95  *    -IP Address option was 'i' now it is 'I' (capital)
  96  *    -Options are now case sensitive
  97  *    -Added validateEmailSyntax() and validateFtpSyntax() functions below<br>
  98  *
  99  *  August 27th, 2004
 100  *    -IP group range is more specific. Used to allow 0-299. Now it is 0-255
 101  *    -Port range more specific. Used to allow 0-69999. Now it is 0-65535<br>
 102  *    -Fixed bug disallowing 'i-' option.<br>
 103  *    -Changed license to GPL
 104  *
 105  *  July 8th, 2004
 106  *    -Fixed bug disallowing 'l-' option. Thanks Dr. Cheap
 107  *
 108  *  June 15, 2004
 109  *    -Added options parameter to make it easier for people to plug the function in
 110  *     without needed to rework the code.
 111  *    -Split the example application away from the function
 112  *
 113  *  June 1, 2004
 114  *    -Complete rewrite
 115  *    -Now more modular
 116  *      -Easier to disable sections
 117  *      -Easier to port to other languages
 118  *      -Easier to port to verify email addresses
 119  *    -Uses only simple regular expressions so it is more portable
 120  *    -Follows RFC closer for domain names. Some "play" domains may break
 121  *    -Renamed from 'verifyUrl()' to 'validateUrlSyntax()'
 122  *    -Removed extra code which added 'http://' and trailing '/' if it was missing
 123  *      -That code was better suited for a massaging function, not verifying
 124  *    -Bug fixes:
 125  *      -Now splits up and forces '/path?query#fragment' order
 126  *      -No longer requires a path when using a query or fragment
 127  *
 128  *  August 29, 2003
 129  *    -Allowed port numbers above 9999. Now allows up to 69999
 130  *
 131  *  Sometime, 2002
 132  *    -Added new top level domains
 133  *      -aero, coop, museum, name, info, biz, pro
 134  *
 135  *  October 5, 2000
 136  *    -First Version
 137  *
 138  *
 139  * Intentional Limitations:
 140  *  -Does not verify url actually exists. Only validates the syntax
 141  *  -Strictly follows the RFC standards. Some urls exist in the wild which will
 142  *   not validate. Including ones with square brackets in the query section '[]'
 143  *
 144  *
 145  * Known Problems:
 146  *  -None at this time
 147  *
 148  *
 149  * Author(s):
 150  *  Rod Apeldoorn - rod(at)canowhoopass(dot)com
 151  *
 152  *
 153  * Homepage:
 154  *  http://www.canowhoopass.com/
 155  *
 156  *
 157  * Thanks!:
 158  *  -WEAV -Several members of Weav helped to test - http://weav.bc.ca/
 159  *  -There were also a number of emails from other developers expressing
 160  *   thanks and suggestions. It is nice to be appreciated. Thanks!
 161  *
 162  * Alternate Commercial Licenses:
 163  * For information in regards to alternate licensing, contact me.
 164  *
 165  * @package moodlecore
 166  * @copyright Copyright 2004, Rod Apeldoorn {@link http://www.canowhoopass.com/}
 167  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 168  */
 169
 170 /**
 171  *  BEGINNING OF validateUrlSyntax() function
 172  */
 173 function validateUrlSyntax( $urladdr, $options="" ){
 174
 175     // Force Options parameter to be lower case
 176     // DISABLED PERMAMENTLY - OK to remove from code
 177     //    $options = strtolower($options);
 178
 179     // Check Options Parameter
 180     if (!preg_match( '/^([sHSEFRuPaIpfqr][+?-])*$/', $options ))
 181     {
 182         trigger_error("Options attribute malformed", E_USER_ERROR);
 183     }
 184
 185     // Set Options Array, set defaults if options are not specified
 186     // Scheme
 187     if (strpos( $options, 's') === false) $aOptions['s'] = '?';
 188     else $aOptions['s'] = substr( $options, strpos( $options, 's') + 1, 1);
 189     // http://
 190     if (strpos( $options, 'H') === false) $aOptions['H'] = '?';
 191     else $aOptions['H'] = substr( $options, strpos( $options, 'H') + 1, 1);
 192     // https:// (SSL)
 193     if (strpos( $options, 'S') === false) $aOptions['S'] = '?';
 194     else $aOptions['S'] = substr( $options, strpos( $options, 'S') + 1, 1);
 195     // mailto: (email)
 196     if (strpos( $options, 'E') === false) $aOptions['E'] = '-';
 197     else $aOptions['E'] = substr( $options, strpos( $options, 'E') + 1, 1);
 198     // ftp://
 199     if (strpos( $options, 'F') === false) $aOptions['F'] = '-';
 200     else $aOptions['F'] = substr( $options, strpos( $options, 'F') + 1, 1);
 201     // rtmp://
 202     if (strpos( $options, 'R') === false) $aOptions['R'] = '-';
 203     else $aOptions['R'] = substr( $options, strpos( $options, 'R') + 1, 1);
 204     // User section
 205     if (strpos( $options, 'u') === false) $aOptions['u'] = '?';
 206     else $aOptions['u'] = substr( $options, strpos( $options, 'u') + 1, 1);
 207     // Password in user section
 208     if (strpos( $options, 'P') === false) $aOptions['P'] = '?';
 209     else $aOptions['P'] = substr( $options, strpos( $options, 'P') + 1, 1);
 210     // Address Section
 211     if (strpos( $options, 'a') === false) $aOptions['a'] = '+';
 212     else $aOptions['a'] = substr( $options, strpos( $options, 'a') + 1, 1);
 213     // IP Address in address section
 214     if (strpos( $options, 'I') === false) $aOptions['I'] = '?';
 215     else $aOptions['I'] = substr( $options, strpos( $options, 'I') + 1, 1);
 216     // Port number
 217     if (strpos( $options, 'p') === false) $aOptions['p'] = '?';
 218     else $aOptions['p'] = substr( $options, strpos( $options, 'p') + 1, 1);
 219     // File Path
 220     if (strpos( $options, 'f') === false) $aOptions['f'] = '?';
 221     else $aOptions['f'] = substr( $options, strpos( $options, 'f') + 1, 1);
 222     // Query Section
 223     if (strpos( $options, 'q') === false) $aOptions['q'] = '?';
 224     else $aOptions['q'] = substr( $options, strpos( $options, 'q') + 1, 1);
 225     // Fragment (Anchor)
 226     if (strpos( $options, 'r') === false) $aOptions['r'] = '?';
 227     else $aOptions['r'] = substr( $options, strpos( $options, 'r') + 1, 1);
 228
 229
 230     // Loop through options array, to search for and replace "-" to "{0}" and "+" to ""
 231     foreach($aOptions as $key => $value)
 232     {
 233         if ($value == '-')
 234         {
 235             $aOptions[$key] = '{0}';
 236         }
 237         if ($value == '+')
 238         {
 239             $aOptions[$key] = '';
 240         }
 241     }
 242
 243     // DEBUGGING - Unescape following line to display to screen current option values
 244     // echo '<pre>'; print_r($aOptions); echo '</pre>';
 245
 246
 247     // Preset Allowed Characters
 248     $alphanum    = '[a-zA-Z0-9]';  // Alpha Numeric
 249     $unreserved  = '[a-zA-Z0-9_.!~*' . '\'' . '()-]';
 250     $escaped     = '(%[0-9a-fA-F]{2})'; // Escape sequence - In Hex - %6d would be a 'm'
 251     $reserved    = '[;/?:@&=+$,]'; // Special characters in the URI
 252
 253     // Beginning Regular Expression
 254     // Scheme - Allows for 'http://', 'https://', 'mailto:', 'ftp://' or 'rtmp://'
 255     $scheme            = '(';
 256     if     ($aOptions['H'] === '') { $scheme .= 'http://'; }
 257     elseif ($aOptions['S'] === '') { $scheme .= 'https://'; }
 258     elseif ($aOptions['E'] === '') { $scheme .= 'mailto:'; }
 259     elseif ($aOptions['F'] === '') { $scheme .= 'ftp://'; }
 260     elseif ($aOptions['R'] === '') { $scheme .= 'rtmp://'; }
 261     else
 262     {
 263         if ($aOptions['H'] === '?') { $scheme .= '|(http://)'; }
 264         if ($aOptions['S'] === '?') { $scheme .= '|(https://)'; }
 265         if ($aOptions['E'] === '?') { $scheme .= '|(mailto:)'; }
 266         if ($aOptions['F'] === '?') { $scheme .= '|(ftp://)'; }
 267         if ($aOptions['R'] === '?') { $scheme .= '|(rtmp://)'; }
 268         $scheme = str_replace('(|', '(', $scheme); // fix first pipe
 269     }
 270     $scheme            .= ')' . $aOptions['s'];
 271     // End setting scheme
 272
 273                        // User Info - Allows for 'username@' or 'username:password@'. Note: contrary to rfc, I removed ':' from username section, allowing it only in password.
 274                        //   /---------------- Username -----------------------\  /-------------------------------- Password ------------------------------\
 275     $userinfo          = '((' . $unreserved . '|' . $escaped . '|[;&=+$,]' . ')+(:(' . $unreserved . '|' . $escaped . '|[;:&=+$,]' . ')+)' . $aOptions['P'] . '@)' . $aOptions['u'];
 276
 277                        // IP ADDRESS - Allows 0.0.0.0 to 255.255.255.255
 278     $ipaddress         = '((((2(([0-4][0-9])|(5[0-5])))|([01]?[0-9]?[0-9]))\.){3}((2(([0-4][0-9])|(5[0-5])))|([01]?[0-9]?[0-9])))';
 279
 280                        // Tertiary Domain(s) - Optional - Multi - Although some sites may use other characters, the RFC says tertiary domains have the same naming restrictions as second level domains
 281     $domain_tertiary   = '(' . $alphanum . '(([a-zA-Z0-9-]{0,62})' . $alphanum . ')?\.)*';
 282
 283 /* MDL-9295 - take out domain_secondary here and below, so that URLs like http://localhost/ and lan addresses like http://host/ are accepted.
 284                        // Second Level Domain - Required - First and last characters must be Alpha-numeric. Hyphens are allowed inside.
 285     $domain_secondary  = '(' . $alphanum . '(([a-zA-Z0-9-]{0,62})' . $alphanum . ')?\.)';
 286 */
 287
 288 // we want more relaxed URLs in Moodle: MDL-11462
 289                        // Top Level Domain - First character must be Alpha. Last character must be AlphaNumeric. Hyphens are allowed inside.
 290     $domain_toplevel   = '([a-zA-Z](([a-zA-Z0-9-]*)[a-zA-Z0-9])?)';
 291 /*                       // Top Level Domain - Required - Domain List Current As Of December 2004. Use above escaped line to be forgiving of possible future TLD's
 292     $domain_toplevel   = '(aero|biz|com|coop|edu|gov|info|int|jobs|mil|mobi|museum|name|net|org|post|pro|travel|ac|ad|ae|af|ag|ai|al|am|an|ao|aq|ar|as|at|au|aw|az|ax|ba|bb|bd|be|bf|bg|bh|bi|bj|bm|bn|bo|br|bs|bt|bv|bw|by|bz|ca|cc|cd|cf|cg|ch|ci|ck|cl|cm|cn|co|cr|cs|cu|cv|cx|cy|cz|de|dj|dk|dm|do|dz|ec|ee|eg|eh|er|es|et|eu|fi|fj|fk|fm|fo|fr|ga|gb|gd|ge|gf|gg|gh|gi|gl|gm|gn|gp|gq|gr|gs|gt|gu|gw|gy|hk|hm|hn|hr|ht|hu|id|ie|il|im|in|io|iq|ir|is|it|je|jm|jo|jp|ke|kg|kh|ki|km|kn|kp|kr|kw|ky|kz|la|lb|lc|li|lk|lr|ls|lt|lu|lv|ly|ma|mc|md|mg|mh|mk|ml|mm|mn|mo|mp|mq|mr|ms|mt|mu|mv|mw|mx|my|mz|na|nc|ne|nf|ng|ni|nl|no|np|nr|nu|nz|om|pa|pe|pf|pg|ph|pk|pl|pm|pn|pr|ps|pt|pw|py|qa|re|ro|ru|rw|sa|sb|sc|sd|se|sg|sh|si|sj|sk|sl|sm|sn|so|sr|st|sv|sy|sz|tc|td|tf|tg|th|tj|tk|tl|tm|tn|to|tp|tr|tt|tv|tw|tz|ua|ug|uk|um|us|uy|uz|va|vc|ve|vg|vi|vn|vu|wf|ws|ye|yt|yu|za|zm|zw)';
 293 */
 294
 295                        // Address can be IP address or Domain
 296     if ($aOptions['I'] === '{0}') {       // IP Address Not Allowed
 297         $address       = '(' . $domain_tertiary . /* MDL-9295 $domain_secondary . */ $domain_toplevel . ')';
 298     } elseif ($aOptions['I'] === '') {  // IP Address Required
 299         $address       = '(' . $ipaddress . ')';
 300     } else {                            // IP Address Optional
 301         $address       = '((' . $ipaddress . ')|(' . $domain_tertiary . /* MDL-9295 $domain_secondary . */ $domain_toplevel . '))';
 302     }
 303     $address = $address . $aOptions['a'];
 304
 305                        // Port Number - :80 or :8080 or :65534 Allows range of :0 to :65535
 306                        //    (0-59999)         |(60000-64999)   |(65000-65499)    |(65500-65529)  |(65530-65535)
 307     $port_number       = '(:(([0-5]?[0-9]{1,4})|(6[0-4][0-9]{3})|(65[0-4][0-9]{2})|(655[0-2][0-9])|(6553[0-5])))' . $aOptions['p'];
 308
 309                        // Path - Can be as simple as '/' or have multiple folders and filenames
 310     $path              = '(/((;)?(' . $unreserved . '|' . $escaped . '|' . '[:@&=+$,]' . ')+(/)?)*)' . $aOptions['f'];
 311
 312                        // Query Section - Accepts ?var1=value1&var2=value2 or ?2393,1221 and much more
 313     $querystring       = '(\?(' . $reserved . '|' . $unreserved . '|' . $escaped . ')*)' . $aOptions['q'];
 314
 315                        // Fragment Section - Accepts anchors such as #top
 316     $fragment          = '(\#(' . $reserved . '|' . $unreserved . '|' . $escaped . ')*)' . $aOptions['r'];
 317
 318
 319     // Building Regular Expression
 320     $regexp = '#^' . $scheme . $userinfo . $address . $port_number . $path . $querystring . $fragment . '$#i';
 321
 322     // DEBUGGING - Uncomment Line Below To Display The Regular Expression Built
 323     // echo '<pre>' . htmlentities(wordwrap($regexp,70,"\n",1)) . '</pre>';
 324
 325     // Running the regular expression
 326     if (preg_match( $regexp, $urladdr ))
 327     {
 328         return true; // The domain passed
 329     }
 330     else
 331     {
 332         return false; // The domain didn't pass the expression
 333     }
 334
 335 } // END Function validateUrlSyntax()
 336
 337
 338
 339 /**
 340  * About ValidateEmailSyntax():
 341  * This function uses the ValidateUrlSyntax() function to easily check the
 342  * syntax of an email address. It accepts the same options as ValidateURLSyntax
 343  * but defaults them for email addresses.
 344  *
 345  *
 346  * Usage:
 347  * <code>
 348  *  validateEmailSyntax( url_to_check[, options])
 349  * </code>
 350  *  url_to_check - string - The url to check
 351  *
 352  *  options - string - A optional string of options to set which parts of
 353  *          the url are required, optional, or not allowed. Each option
 354  *          must be followed by a "+" for required, "?" for optional, or
 355  *          "-" for not allowed. See ValidateUrlSyntax() docs for option list.
 356  *
 357  *  The default options are changed to:
 358  *      s-H-S-E+F-u+P-a+I-p-f-q-r-
 359  *
 360  *  This only allows an address of "name@domain".
 361  *
 362  * Examples:
 363  * <code>
 364  *  validateEmailSyntax('george@fakemail.com')
 365  *  validateEmailSyntax('mailto:george@fakemail.com', 's+')
 366  *  validateEmailSyntax('george@fakemail.com?subject=Hi%20George', 'q?')
 367  *  validateEmailSyntax('george@212.198.33.12', 'I?')
 368  * </code>
 369  *
 370  *
 371  * Author(s):
 372  *  Rod Apeldoorn - rod(at)canowhoopass(dot)com
 373  *
 374  *
 375  * Homepage:
 376  *  http://www.canowhoopass.com/
 377  *
 378  *
 379  * License:
 380  *  Copyright 2004 - Rod Apeldoorn
 381  *
 382  *  Released under same license as validateUrlSyntax(). For details, contact me.
 383  */
 384
 385 function validateEmailSyntax( $emailaddr, $options="" ){
 386
 387     // Check Options Parameter
 388     if (!preg_match( '/^([sHSEFuPaIpfqr][+?-])*$/', $options ))
 389     {
 390         trigger_error("Options attribute malformed", E_USER_ERROR);
 391     }
 392
 393     // Set Options Array, set defaults if options are not specified
 394     // Scheme
 395     if (strpos( $options, 's') === false) $aOptions['s'] = '-';
 396     else $aOptions['s'] = substr( $options, strpos( $options, 's') + 1, 1);
 397     // http://
 398     if (strpos( $options, 'H') === false) $aOptions['H'] = '-';
 399     else $aOptions['H'] = substr( $options, strpos( $options, 'H') + 1, 1);
 400     // https:// (SSL)
 401     if (strpos( $options, 'S') === false) $aOptions['S'] = '-';
 402     else $aOptions['S'] = substr( $options, strpos( $options, 'S') + 1, 1);
 403     // mailto: (email)
 404     if (strpos( $options, 'E') === false) $aOptions['E'] = '?';
 405     else $aOptions['E'] = substr( $options, strpos( $options, 'E') + 1, 1);
 406     // ftp://
 407     if (strpos( $options, 'F') === false) $aOptions['F'] = '-';
 408     else $aOptions['F'] = substr( $options, strpos( $options, 'F') + 1, 1);
 409     // User section
 410     if (strpos( $options, 'u') === false) $aOptions['u'] = '+';
 411     else $aOptions['u'] = substr( $options, strpos( $options, 'u') + 1, 1);
 412     // Password in user section
 413     if (strpos( $options, 'P') === false) $aOptions['P'] = '-';
 414     else $aOptions['P'] = substr( $options, strpos( $options, 'P') + 1, 1);
 415     // Address Section
 416     if (strpos( $options, 'a') === false) $aOptions['a'] = '+';
 417     else $aOptions['a'] = substr( $options, strpos( $options, 'a') + 1, 1);
 418     // IP Address in address section
 419     if (strpos( $options, 'I') === false) $aOptions['I'] = '-';
 420     else $aOptions['I'] = substr( $options, strpos( $options, 'I') + 1, 1);
 421     // Port number
 422     if (strpos( $options, 'p') === false) $aOptions['p'] = '-';
 423     else $aOptions['p'] = substr( $options, strpos( $options, 'p') + 1, 1);
 424     // File Path
 425     if (strpos( $options, 'f') === false) $aOptions['f'] = '-';
 426     else $aOptions['f'] = substr( $options, strpos( $options, 'f') + 1, 1);
 427     // Query Section
 428     if (strpos( $options, 'q') === false) $aOptions['q'] = '-';
 429     else $aOptions['q'] = substr( $options, strpos( $options, 'q') + 1, 1);
 430     // Fragment (Anchor)
 431     if (strpos( $options, 'r') === false) $aOptions['r'] = '-';
 432     else $aOptions['r'] = substr( $options, strpos( $options, 'r') + 1, 1);
 433
 434     // Generate options
 435     $newoptions = '';
 436     foreach($aOptions as $key => $value)
 437     {
 438         $newoptions .= $key . $value;
 439     }
 440
 441     // DEBUGGING - Uncomment line below to display generated options
 442     // echo '<pre>' . $newoptions . '</pre>';
 443
 444     // Send to validateUrlSyntax() and return result
 445     return validateUrlSyntax( $emailaddr, $newoptions);
 446
 447 } // END Function validateEmailSyntax()
 448
 449
 450
 451 /**
 452  * About ValidateFtpSyntax():
 453  * This function uses the ValidateUrlSyntax() function to easily check the
 454  * syntax of an FTP address. It accepts the same options as ValidateURLSyntax
 455  * but defaults them for FTP addresses.
 456  *
 457  *
 458  * Usage:
 459  * <code>
 460  *  validateFtpSyntax( url_to_check[, options])
 461  * </code>
 462  *  url_to_check - string - The url to check
 463  *
 464  *  options - string - A optional string of options to set which parts of
 465  *          the url are required, optional, or not allowed. Each option
 466  *          must be followed by a "+" for required, "?" for optional, or
 467  *          "-" for not allowed. See ValidateUrlSyntax() docs for option list.
 468  *
 469  *  The default options are changed to:
 470  *      s?H-S-E-F+u?P?a+I?p?f?q-r-
 471  *
 472  * Examples:
 473  * <code>
 474  *  validateFtpSyntax('ftp://netscape.com')
 475  *  validateFtpSyntax('moz:iesucks@netscape.com')
 476  *  validateFtpSyntax('ftp://netscape.com:2121/browsers/ns7/', 'u-')
 477  * </code>
 478  *
 479  * Author(s):
 480  *  Rod Apeldoorn - rod(at)canowhoopass(dot)com
 481  *
 482  *
 483  * Homepage:
 484  *  http://www.canowhoopass.com/
 485  *
 486  *
 487  * License:
 488  *  Copyright 2004 - Rod Apeldoorn
 489  *
 490  *  Released under same license as validateUrlSyntax(). For details, contact me.
 491  */
 492
 493 function validateFtpSyntax( $ftpaddr, $options="" ){
 494
 495     // Check Options Parameter
 496     if (!preg_match( '/^([sHSEFuPaIpfqr][+?-])*$/', $options ))
 497     {
 498         trigger_error("Options attribute malformed", E_USER_ERROR);
 499     }
 500
 501     // Set Options Array, set defaults if options are not specified
 502     // Scheme
 503     if (strpos( $options, 's') === false) $aOptions['s'] = '?';
 504     else $aOptions['s'] = substr( $options, strpos( $options, 's') + 1, 1);
 505     // http://
 506     if (strpos( $options, 'H') === false) $aOptions['H'] = '-';
 507     else $aOptions['H'] = substr( $options, strpos( $options, 'H') + 1, 1);
 508     // https:// (SSL)
 509     if (strpos( $options, 'S') === false) $aOptions['S'] = '-';
 510     else $aOptions['S'] = substr( $options, strpos( $options, 'S') + 1, 1);
 511     // mailto: (email)
 512     if (strpos( $options, 'E') === false) $aOptions['E'] = '-';
 513     else $aOptions['E'] = substr( $options, strpos( $options, 'E') + 1, 1);
 514     // ftp://
 515     if (strpos( $options, 'F') === false) $aOptions['F'] = '+';
 516     else $aOptions['F'] = substr( $options, strpos( $options, 'F') + 1, 1);
 517     // User section
 518     if (strpos( $options, 'u') === false) $aOptions['u'] = '?';
 519     else $aOptions['u'] = substr( $options, strpos( $options, 'u') + 1, 1);
 520     // Password in user section
 521     if (strpos( $options, 'P') === false) $aOptions['P'] = '?';
 522     else $aOptions['P'] = substr( $options, strpos( $options, 'P') + 1, 1);
 523     // Address Section
 524     if (strpos( $options, 'a') === false) $aOptions['a'] = '+';
 525     else $aOptions['a'] = substr( $options, strpos( $options, 'a') + 1, 1);
 526     // IP Address in address section
 527     if (strpos( $options, 'I') === false) $aOptions['I'] = '?';
 528     else $aOptions['I'] = substr( $options, strpos( $options, 'I') + 1, 1);
 529     // Port number
 530     if (strpos( $options, 'p') === false) $aOptions['p'] = '?';
 531     else $aOptions['p'] = substr( $options, strpos( $options, 'p') + 1, 1);
 532     // File Path
 533     if (strpos( $options, 'f') === false) $aOptions['f'] = '?';
 534     else $aOptions['f'] = substr( $options, strpos( $options, 'f') + 1, 1);
 535     // Query Section
 536     if (strpos( $options, 'q') === false) $aOptions['q'] = '-';
 537     else $aOptions['q'] = substr( $options, strpos( $options, 'q') + 1, 1);
 538     // Fragment (Anchor)
 539     if (strpos( $options, 'r') === false) $aOptions['r'] = '-';
 540     else $aOptions['r'] = substr( $options, strpos( $options, 'r') + 1, 1);
 541
 542     // Generate options
 543     $newoptions = '';
 544     foreach($aOptions as $key => $value)
 545     {
 546         $newoptions .= $key . $value;
 547     }
 548
 549     // DEBUGGING - Uncomment line below to display generated options
 550     // echo '<pre>' . $newoptions . '</pre>';
 551
 552     // Send to validateUrlSyntax() and return result
 553     return validateUrlSyntax( $ftpaddr, $newoptions);
 554
 555 } // END Function validateFtpSyntax()