crm.fsf.org/20131203/files/sites/all/modules-new/civicrm/packages/Mail/RFC822.php

   1 <?php
   2 /**
   3  * RFC 822 Email address list validation Utility
   4  *
   5  * PHP versions 4 and 5
   6  *
   7  * LICENSE:
   8  *
   9  * Copyright (c) 2001-2010, Richard Heyes
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  *
  16  * o Redistributions of source code must retain the above copyright
  17  *   notice, this list of conditions and the following disclaimer.
  18  * o Redistributions in binary form must reproduce the above copyright
  19  *   notice, this list of conditions and the following disclaimer in the
  20  *   documentation and/or other materials provided with the distribution.
  21  * o The names of the authors may not be used to endorse or promote
  22  *   products derived from this software without specific prior written
  23  *   permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  26  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  27  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  28  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  29  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  30  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  31  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  35  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  *
  37  * @category    Mail
  38  * @package     Mail
  39  * @author      Richard Heyes <richard@phpguru.org>
  40  * @author      Chuck Hagenbuch <chuck@horde.org
  41  * @copyright   2001-2010 Richard Heyes
  42  * @license     http://opensource.org/licenses/bsd-license.php New BSD License
  43  * @version     CVS: $Id: RFC822.php 294749 2010-02-08 08:22:25Z clockwerx $
  44  * @link        http://pear.php.net/package/Mail/
  45  */
  46
  47 /**
  48  * RFC 822 Email address list validation Utility
  49  *
  50  * What is it?
  51  *
  52  * This class will take an address string, and parse it into it's consituent
  53  * parts, be that either addresses, groups, or combinations. Nested groups
  54  * are not supported. The structure it returns is pretty straight forward,
  55  * and is similar to that provided by the imap_rfc822_parse_adrlist(). Use
  56  * print_r() to view the structure.
  57  *
  58  * How do I use it?
  59  *
  60  * $address_string = 'My Group: "Richard" <richard@localhost> (A comment), ted@example.com (Ted Bloggs), Barney;';
  61  * $structure = Mail_RFC822::parseAddressList($address_string, 'example.com', true)
  62  * print_r($structure);
  63  *
  64  * @author  Richard Heyes <richard@phpguru.org>
  65  * @author  Chuck Hagenbuch <chuck@horde.org>
  66  * @version $Revision: 294749 $
  67  * @license BSD
  68  * @package Mail
  69  */
  70 class Mail_RFC822 {
  71
  72     /**
  73      * The address being parsed by the RFC822 object.
  74      * @var string $address
  75      */
  76     var $address = '';
  77
  78     /**
  79      * The default domain to use for unqualified addresses.
  80      * @var string $default_domain
  81      */
  82     var $default_domain = 'localhost';
  83
  84     /**
  85      * Should we return a nested array showing groups, or flatten everything?
  86      * @var boolean $nestGroups
  87      */
  88     var $nestGroups = true;
  89
  90     /**
  91      * Whether or not to validate atoms for non-ascii characters.
  92      * @var boolean $validate
  93      */
  94     var $validate = true;
  95
  96     /**
  97      * The array of raw addresses built up as we parse.
  98      * @var array $addresses
  99      */
 100     var $addresses = array();
 101
 102     /**
 103      * The final array of parsed address information that we build up.
 104      * @var array $structure
 105      */
 106     var $structure = array();
 107
 108     /**
 109      * The current error message, if any.
 110      * @var string $error
 111      */
 112     var $error = null;
 113
 114     /**
 115      * An internal counter/pointer.
 116      * @var integer $index
 117      */
 118     var $index = null;
 119
 120     /**
 121      * The number of groups that have been found in the address list.
 122      * @var integer $num_groups
 123      * @access public
 124      */
 125     var $num_groups = 0;
 126
 127     /**
 128      * A variable so that we can tell whether or not we're inside a
 129      * Mail_RFC822 object.
 130      * @var boolean $mailRFC822
 131      */
 132     var $mailRFC822 = true;
 133
 134     /**
 135     * A limit after which processing stops
 136     * @var int $limit
 137     */
 138     var $limit = null;
 139
 140     /**
 141      * Sets up the object. The address must either be set here or when
 142      * calling parseAddressList(). One or the other.
 143      *
 144      * @access public
 145      * @param string  $address         The address(es) to validate.
 146      * @param string  $default_domain  Default domain/host etc. If not supplied, will be set to localhost.
 147      * @param boolean $nest_groups     Whether to return the structure with groups nested for easier viewing.
 148      * @param boolean $validate        Whether to validate atoms. Turn this off if you need to run addresses through before encoding the personal names, for instance.
 149      *
 150      * @return object Mail_RFC822 A new Mail_RFC822 object.
 151      */
 152     function Mail_RFC822($address = null, $default_domain = null, $nest_groups = null, $validate = null, $limit = null)
 153     {
 154         if (isset($address))        $this->address        = $address;
 155         if (isset($default_domain)) $this->default_domain = $default_domain;
 156         if (isset($nest_groups))    $this->nestGroups     = $nest_groups;
 157         if (isset($validate))       $this->validate       = $validate;
 158         if (isset($limit))          $this->limit          = $limit;
 159     }
 160
 161     /**
 162      * Starts the whole process. The address must either be set here
 163      * or when creating the object. One or the other.
 164      *
 165      * @access public
 166      * @param string  $address         The address(es) to validate.
 167      * @param string  $default_domain  Default domain/host etc.
 168      * @param boolean $nest_groups     Whether to return the structure with groups nested for easier viewing.
 169      * @param boolean $validate        Whether to validate atoms. Turn this off if you need to run addresses through before encoding the personal names, for instance.
 170      *
 171      * @return array A structured array of addresses.
 172      */
 173     function parseAddressList($address = null, $default_domain = null, $nest_groups = null, $validate = null, $limit = null)
 174     {
 175         if (!isset($this) || !isset($this->mailRFC822)) {
 176             $obj = new Mail_RFC822($address, $default_domain, $nest_groups, $validate, $limit);
 177             return $obj->parseAddressList();
 178         }
 179
 180         if (isset($address))        $this->address        = $address;
 181         if (isset($default_domain)) $this->default_domain = $default_domain;
 182         if (isset($nest_groups))    $this->nestGroups     = $nest_groups;
 183         if (isset($validate))       $this->validate       = $validate;
 184         if (isset($limit))          $this->limit          = $limit;
 185
 186         $this->structure  = array();
 187         $this->addresses  = array();
 188         $this->error      = null;
 189         $this->index      = null;
 190
 191         // Unfold any long lines in $this->address.
 192         $this->address = preg_replace('/\r?\n/', "\r\n", $this->address);
 193         $this->address = preg_replace('/\r\n(\t| )+/', ' ', $this->address);
 194
 195         while ($this->address = $this->_splitAddresses($this->address));
 196
 197         if ($this->address === false || isset($this->error)) {
 198             require_once 'PEAR.php';
 199             return PEAR::raiseError($this->error);
 200         }
 201
 202         // Validate each address individually.  If we encounter an invalid
 203         // address, stop iterating and return an error immediately.
 204         foreach ($this->addresses as $address) {
 205             $valid = $this->_validateAddress($address);
 206
 207             if ($valid === false || isset($this->error)) {
 208                 require_once 'PEAR.php';
 209                 return PEAR::raiseError($this->error);
 210             }
 211
 212             if (!$this->nestGroups) {
 213                 $this->structure = array_merge($this->structure, $valid);
 214             } else {
 215                 $this->structure[] = $valid;
 216             }
 217         }
 218
 219         return $this->structure;
 220     }
 221
 222     /**
 223      * Splits an address into separate addresses.
 224      *
 225      * @access private
 226      * @param string $address The addresses to split.
 227      * @return boolean Success or failure.
 228      */
 229     function _splitAddresses($address)
 230     {
 231         if (!empty($this->limit) && count($this->addresses) == $this->limit) {
 232             return '';
 233         }
 234
 235         if ($this->_isGroup($address) && !isset($this->error)) {
 236             $split_char = ';';
 237             $is_group   = true;
 238         } elseif (!isset($this->error)) {
 239             $split_char = ',';
 240             $is_group   = false;
 241         } elseif (isset($this->error)) {
 242             return false;
 243         }
 244
 245         // Split the string based on the above ten or so lines.
 246         $parts  = explode($split_char, $address);
 247         $string = $this->_splitCheck($parts, $split_char);
 248
 249         // If a group...
 250         if ($is_group) {
 251             // If $string does not contain a colon outside of
 252             // brackets/quotes etc then something's fubar.
 253
 254             // First check there's a colon at all:
 255             if (strpos($string, ':') === false) {
 256                 $this->error = 'Invalid address: ' . $string;
 257                 return false;
 258             }
 259
 260             // Now check it's outside of brackets/quotes:
 261             if (!$this->_splitCheck(explode(':', $string), ':')) {
 262                 return false;
 263             }
 264
 265             // We must have a group at this point, so increase the counter:
 266             $this->num_groups++;
 267         }
 268
 269         // $string now contains the first full address/group.
 270         // Add to the addresses array.
 271         $this->addresses[] = array(
 272                                    'address' => trim($string),
 273                                    'group'   => $is_group
 274                                    );
 275
 276         // Remove the now stored address from the initial line, the +1
 277         // is to account for the explode character.
 278         $address = trim(substr($address, strlen($string) + 1));
 279
 280         // If the next char is a comma and this was a group, then
 281         // there are more addresses, otherwise, if there are any more
 282         // chars, then there is another address.
 283         if ($is_group && substr($address, 0, 1) == ','){
 284             $address = trim(substr($address, 1));
 285             return $address;
 286
 287         } elseif (strlen($address) > 0) {
 288             return $address;
 289
 290         } else {
 291             return '';
 292         }
 293
 294         // If you got here then something's off
 295         return false;
 296     }
 297
 298     /**
 299      * Checks for a group at the start of the string.
 300      *
 301      * @access private
 302      * @param string $address The address to check.
 303      * @return boolean Whether or not there is a group at the start of the string.
 304      */
 305     function _isGroup($address)
 306     {
 307         // First comma not in quotes, angles or escaped:
 308         $parts  = explode(',', $address);
 309         $string = $this->_splitCheck($parts, ',');
 310
 311         // Now we have the first address, we can reliably check for a
 312         // group by searching for a colon that's not escaped or in
 313         // quotes or angle brackets.
 314         if (count($parts = explode(':', $string)) > 1) {
 315             $string2 = $this->_splitCheck($parts, ':');
 316             return ($string2 !== $string);
 317         } else {
 318             return false;
 319         }
 320     }
 321
 322     /**
 323      * A common function that will check an exploded string.
 324      *
 325      * @access private
 326      * @param array $parts The exloded string.
 327      * @param string $char  The char that was exploded on.
 328      * @return mixed False if the string contains unclosed quotes/brackets, or the string on success.
 329      */
 330     function _splitCheck($parts, $char)
 331     {
 332         $string = $parts[0];
 333
 334         for ($i = 0; $i < count($parts); $i++) {
 335             if ($this->_hasUnclosedQuotes($string)
 336                 || $this->_hasUnclosedBrackets($string, '<>')
 337                 || $this->_hasUnclosedBrackets($string, '[]')
 338                 || $this->_hasUnclosedBrackets($string, '()')
 339                 || substr($string, -1) == '\\') {
 340                 if (isset($parts[$i + 1])) {
 341                     $string = $string . $char . $parts[$i + 1];
 342                 } else {
 343                     $this->error = 'Invalid address spec. Unclosed bracket or quotes';
 344                     return false;
 345                 }
 346             } else {
 347                 $this->index = $i;
 348                 break;
 349             }
 350         }
 351
 352         return $string;
 353     }
 354
 355     /**
 356      * Checks if a string has unclosed quotes or not.
 357      *
 358      * @access private
 359      * @param string $string  The string to check.
 360      * @return boolean  True if there are unclosed quotes inside the string,
 361      *                  false otherwise.
 362      */
 363     function _hasUnclosedQuotes($string)
 364     {
 365         $string = trim($string);
 366         $iMax = strlen($string);
 367         $in_quote = false;
 368         $i = $slashes = 0;
 369
 370         for (; $i < $iMax; ++$i) {
 371             switch ($string[$i]) {
 372             case '\\':
 373                 ++$slashes;
 374                 break;
 375
 376             case '"':
 377                 if ($slashes % 2 == 0) {
 378                     $in_quote = !$in_quote;
 379                 }
 380                 // Fall through to default action below.
 381
 382             default:
 383                 $slashes = 0;
 384                 break;
 385             }
 386         }
 387
 388         return $in_quote;
 389     }
 390
 391     /**
 392      * Checks if a string has an unclosed brackets or not. IMPORTANT:
 393      * This function handles both angle brackets and square brackets;
 394      *
 395      * @access private
 396      * @param string $string The string to check.
 397      * @param string $chars  The characters to check for.
 398      * @return boolean True if there are unclosed brackets inside the string, false otherwise.
 399      */
 400     function _hasUnclosedBrackets($string, $chars)
 401     {
 402         $num_angle_start = substr_count($string, $chars[0]);
 403         $num_angle_end   = substr_count($string, $chars[1]);
 404
 405         $this->_hasUnclosedBracketsSub($string, $num_angle_start, $chars[0]);
 406         $this->_hasUnclosedBracketsSub($string, $num_angle_end, $chars[1]);
 407
 408         if ($num_angle_start < $num_angle_end) {
 409             $this->error = 'Invalid address spec. Unmatched quote or bracket (' . $chars . ')';
 410             return false;
 411         } else {
 412             return ($num_angle_start > $num_angle_end);
 413         }
 414     }
 415
 416     /**
 417      * Sub function that is used only by hasUnclosedBrackets().
 418      *
 419      * @access private
 420      * @param string $string The string to check.
 421      * @param integer &$num    The number of occurences.
 422      * @param string $char   The character to count.
 423      * @return integer The number of occurences of $char in $string, adjusted for backslashes.
 424      */
 425     function _hasUnclosedBracketsSub($string, &$num, $char)
 426     {
 427         $parts = explode($char, $string);
 428         for ($i = 0; $i < count($parts); $i++){
 429             if (substr($parts[$i], -1) == '\\' || $this->_hasUnclosedQuotes($parts[$i]))
 430                 $num--;
 431             if (isset($parts[$i + 1]))
 432                 $parts[$i + 1] = $parts[$i] . $char . $parts[$i + 1];
 433         }
 434
 435         return $num;
 436     }
 437
 438     /**
 439      * Function to begin checking the address.
 440      *
 441      * @access private
 442      * @param string $address The address to validate.
 443      * @return mixed False on failure, or a structured array of address information on success.
 444      */
 445     function _validateAddress($address)
 446     {
 447         $is_group = false;
 448         $addresses = array();
 449
 450         if ($address['group']) {
 451             $is_group = true;
 452
 453             // Get the group part of the name
 454             $parts     = explode(':', $address['address']);
 455             $groupname = $this->_splitCheck($parts, ':');
 456             $structure = array();
 457
 458             // And validate the group part of the name.
 459             if (!$this->_validatePhrase($groupname)){
 460                 $this->error = 'Group name did not validate.';
 461                 return false;
 462             } else {
 463                 // Don't include groups if we are not nesting
 464                 // them. This avoids returning invalid addresses.
 465                 if ($this->nestGroups) {
 466                     $structure = new stdClass;
 467                     $structure->groupname = $groupname;
 468                 }
 469             }
 470
 471             $address['address'] = ltrim(substr($address['address'], strlen($groupname . ':')));
 472         }
 473
 474         // If a group then split on comma and put into an array.
 475         // Otherwise, Just put the whole address in an array.
 476         if ($is_group) {
 477             while (strlen($address['address']) > 0) {
 478                 $parts       = explode(',', $address['address']);
 479                 $addresses[] = $this->_splitCheck($parts, ',');
 480                 $address['address'] = trim(substr($address['address'], strlen(end($addresses) . ',')));
 481             }
 482         } else {
 483             $addresses[] = $address['address'];
 484         }
 485
 486         // Check that $addresses is set, if address like this:
 487         // Groupname:;
 488         // Then errors were appearing.
 489         if (!count($addresses)){
 490             $this->error = 'Empty group.';
 491             return false;
 492         }
 493
 494         // Trim the whitespace from all of the address strings.
 495         array_map('trim', $addresses);
 496
 497         // Validate each mailbox.
 498         // Format could be one of: name <geezer@domain.com>
 499         //                         geezer@domain.com
 500         //                         geezer
 501         // ... or any other format valid by RFC 822.
 502         for ($i = 0; $i < count($addresses); $i++) {
 503             if (!$this->validateMailbox($addresses[$i])) {
 504                 if (empty($this->error)) {
 505                     $this->error = 'Validation failed for: ' . $addresses[$i];
 506                 }
 507                 return false;
 508             }
 509         }
 510
 511         // Nested format
 512         if ($this->nestGroups) {
 513             if ($is_group) {
 514                 $structure->addresses = $addresses;
 515             } else {
 516                 $structure = $addresses[0];
 517             }
 518
 519         // Flat format
 520         } else {
 521             if ($is_group) {
 522                 $structure = array_merge($structure, $addresses);
 523             } else {
 524                 $structure = $addresses;
 525             }
 526         }
 527
 528         return $structure;
 529     }
 530
 531     /**
 532      * Function to validate a phrase.
 533      *
 534      * @access private
 535      * @param string $phrase The phrase to check.
 536      * @return boolean Success or failure.
 537      */
 538     function _validatePhrase($phrase)
 539     {
 540         // Splits on one or more Tab or space.
 541         $parts = preg_split('/[ \\x09]+/', $phrase, -1, PREG_SPLIT_NO_EMPTY);
 542
 543         $phrase_parts = array();
 544         while (count($parts) > 0){
 545             $phrase_parts[] = $this->_splitCheck($parts, ' ');
 546             for ($i = 0; $i < $this->index + 1; $i++)
 547                 array_shift($parts);
 548         }
 549
 550         foreach ($phrase_parts as $part) {
 551             // If quoted string:
 552             if (substr($part, 0, 1) == '"') {
 553                 if (!$this->_validateQuotedString($part)) {
 554                     return false;
 555                 }
 556                 continue;
 557             }
 558
 559             // Otherwise it's an atom:
 560             if (!$this->_validateAtom($part)) return false;
 561         }
 562
 563         return true;
 564     }
 565
 566     /**
 567      * Function to validate an atom which from rfc822 is:
 568      * atom = 1*<any CHAR except specials, SPACE and CTLs>
 569      *
 570      * If validation ($this->validate) has been turned off, then
 571      * validateAtom() doesn't actually check anything. This is so that you
 572      * can split a list of addresses up before encoding personal names
 573      * (umlauts, etc.), for example.
 574      *
 575      * @access private
 576      * @param string $atom The string to check.
 577      * @return boolean Success or failure.
 578      */
 579     function _validateAtom($atom)
 580     {
 581         if (!$this->validate) {
 582             // Validation has been turned off; assume the atom is okay.
 583             return true;
 584         }
 585
 586         // Check for any char from ASCII 0 - ASCII 127
 587         if (!preg_match('/^[\\x00-\\x7E]+$/i', $atom, $matches)) {
 588             return false;
 589         }
 590
 591         // Check for specials:
 592         if (preg_match('/[][()<>@,;\\:". ]/', $atom)) {
 593             return false;
 594         }
 595
 596         // Check for control characters (ASCII 0-31):
 597         if (preg_match('/[\\x00-\\x1F]+/', $atom)) {
 598             return false;
 599         }
 600
 601         return true;
 602     }
 603
 604     /**
 605      * Function to validate quoted string, which is:
 606      * quoted-string = <"> *(qtext/quoted-pair) <">
 607      *
 608      * @access private
 609      * @param string $qstring The string to check
 610      * @return boolean Success or failure.
 611      */
 612     function _validateQuotedString($qstring)
 613     {
 614         // Leading and trailing "
 615         $qstring = substr($qstring, 1, -1);
 616
 617         // Perform check, removing quoted characters first.
 618         return !preg_match('/[\x0D\\\\"]/', preg_replace('/\\\\./', '', $qstring));
 619     }
 620
 621     /**
 622      * Function to validate a mailbox, which is:
 623      * mailbox =   addr-spec         ; simple address
 624      *           / phrase route-addr ; name and route-addr
 625      *
 626      * @access public
 627      * @param string &$mailbox The string to check.
 628      * @return boolean Success or failure.
 629      */
 630     function validateMailbox(&$mailbox)
 631     {
 632         // A couple of defaults.
 633         $phrase  = '';
 634         $comment = '';
 635         $comments = array();
 636
 637         // Catch any RFC822 comments and store them separately.
 638         $_mailbox = $mailbox;
 639         while (strlen(trim($_mailbox)) > 0) {
 640             $parts = explode('(', $_mailbox);
 641             $before_comment = $this->_splitCheck($parts, '(');
 642             if ($before_comment != $_mailbox) {
 643                 // First char should be a (.
 644                 $comment    = substr(str_replace($before_comment, '', $_mailbox), 1);
 645                 $parts      = explode(')', $comment);
 646                 $comment    = $this->_splitCheck($parts, ')');
 647                 $comments[] = $comment;
 648
 649                 // +2 is for the brackets
 650                 $_mailbox = substr($_mailbox, strpos($_mailbox, '('.$comment)+strlen($comment)+2);
 651             } else {
 652                 break;
 653             }
 654         }
 655
 656         foreach ($comments as $comment) {
 657             $mailbox = str_replace("($comment)", '', $mailbox);
 658         }
 659
 660         $mailbox = trim($mailbox);
 661
 662         // Check for name + route-addr
 663         if (substr($mailbox, -1) == '>' && substr($mailbox, 0, 1) != '<') {
 664             $parts  = explode('<', $mailbox);
 665             $name   = $this->_splitCheck($parts, '<');
 666
 667             $phrase     = trim($name);
 668             $route_addr = trim(substr($mailbox, strlen($name.'<'), -1));
 669
 670             if ($this->_validatePhrase($phrase) === false || ($route_addr = $this->_validateRouteAddr($route_addr)) === false) {
 671                 return false;
 672             }
 673
 674         // Only got addr-spec
 675         } else {
 676             // First snip angle brackets if present.
 677             if (substr($mailbox, 0, 1) == '<' && substr($mailbox, -1) == '>') {
 678                 $addr_spec = substr($mailbox, 1, -1);
 679             } else {
 680                 $addr_spec = $mailbox;
 681             }
 682
 683             if (($addr_spec = $this->_validateAddrSpec($addr_spec)) === false) {
 684                 return false;
 685             }
 686         }
 687
 688         // Construct the object that will be returned.
 689         $mbox = new stdClass();
 690
 691         // Add the phrase (even if empty) and comments
 692         $mbox->personal = $phrase;
 693         $mbox->comment  = isset($comments) ? $comments : array();
 694
 695         if (isset($route_addr)) {
 696             $mbox->mailbox = $route_addr['local_part'];
 697             $mbox->host    = $route_addr['domain'];
 698             $route_addr['adl'] !== '' ? $mbox->adl = $route_addr['adl'] : '';
 699         } else {
 700             $mbox->mailbox = $addr_spec['local_part'];
 701             $mbox->host    = $addr_spec['domain'];
 702         }
 703
 704         $mailbox = $mbox;
 705         return true;
 706     }
 707
 708     /**
 709      * This function validates a route-addr which is:
 710      * route-addr = "<" [route] addr-spec ">"
 711      *
 712      * Angle brackets have already been removed at the point of
 713      * getting to this function.
 714      *
 715      * @access private
 716      * @param string $route_addr The string to check.
 717      * @return mixed False on failure, or an array containing validated address/route information on success.
 718      */
 719     function _validateRouteAddr($route_addr)
 720     {
 721         // Check for colon.
 722         if (strpos($route_addr, ':') !== false) {
 723             $parts = explode(':', $route_addr);
 724             $route = $this->_splitCheck($parts, ':');
 725         } else {
 726             $route = $route_addr;
 727         }
 728
 729         // If $route is same as $route_addr then the colon was in
 730         // quotes or brackets or, of course, non existent.
 731         if ($route === $route_addr){
 732             unset($route);
 733             $addr_spec = $route_addr;
 734             if (($addr_spec = $this->_validateAddrSpec($addr_spec)) === false) {
 735                 return false;
 736             }
 737         } else {
 738             // Validate route part.
 739             if (($route = $this->_validateRoute($route)) === false) {
 740                 return false;
 741             }
 742
 743             $addr_spec = substr($route_addr, strlen($route . ':'));
 744
 745             // Validate addr-spec part.
 746             if (($addr_spec = $this->_validateAddrSpec($addr_spec)) === false) {
 747                 return false;
 748             }
 749         }
 750
 751         if (isset($route)) {
 752             $return['adl'] = $route;
 753         } else {
 754             $return['adl'] = '';
 755         }
 756
 757         $return = array_merge($return, $addr_spec);
 758         return $return;
 759     }
 760
 761     /**
 762      * Function to validate a route, which is:
 763      * route = 1#("@" domain) ":"
 764      *
 765      * @access private
 766      * @param string $route The string to check.
 767      * @return mixed False on failure, or the validated $route on success.
 768      */
 769     function _validateRoute($route)
 770     {
 771         // Split on comma.
 772         $domains = explode(',', trim($route));
 773
 774         foreach ($domains as $domain) {
 775             $domain = str_replace('@', '', trim($domain));
 776             if (!$this->_validateDomain($domain)) return false;
 777         }
 778
 779         return $route;
 780     }
 781
 782     /**
 783      * Function to validate a domain, though this is not quite what
 784      * you expect of a strict internet domain.
 785      *
 786      * domain = sub-domain *("." sub-domain)
 787      *
 788      * @access private
 789      * @param string $domain The string to check.
 790      * @return mixed False on failure, or the validated domain on success.
 791      */
 792     function _validateDomain($domain)
 793     {
 794         // Note the different use of $subdomains and $sub_domains
 795         $subdomains = explode('.', $domain);
 796
 797         while (count($subdomains) > 0) {
 798             $sub_domains[] = $this->_splitCheck($subdomains, '.');
 799             for ($i = 0; $i < $this->index + 1; $i++)
 800                 array_shift($subdomains);
 801         }
 802
 803         foreach ($sub_domains as $sub_domain) {
 804             if (!$this->_validateSubdomain(trim($sub_domain)))
 805                 return false;
 806         }
 807
 808         // Managed to get here, so return input.
 809         return $domain;
 810     }
 811
 812     /**
 813      * Function to validate a subdomain:
 814      *   subdomain = domain-ref / domain-literal
 815      *
 816      * @access private
 817      * @param string $subdomain The string to check.
 818      * @return boolean Success or failure.
 819      */
 820     function _validateSubdomain($subdomain)
 821     {
 822         if (preg_match('|^\[(.*)]$|', $subdomain, $arr)){
 823             if (!$this->_validateDliteral($arr[1])) return false;
 824         } else {
 825             if (!$this->_validateAtom($subdomain)) return false;
 826         }
 827
 828         // Got here, so return successful.
 829         return true;
 830     }
 831
 832     /**
 833      * Function to validate a domain literal:
 834      *   domain-literal =  "[" *(dtext / quoted-pair) "]"
 835      *
 836      * @access private
 837      * @param string $dliteral The string to check.
 838      * @return boolean Success or failure.
 839      */
 840     function _validateDliteral($dliteral)
 841     {
 842         return !preg_match('/(.)[][\x0D\\\\]/', $dliteral, $matches) && $matches[1] != '\\';
 843     }
 844
 845     /**
 846      * Function to validate an addr-spec.
 847      *
 848      * addr-spec = local-part "@" domain
 849      *
 850      * @access private
 851      * @param string $addr_spec The string to check.
 852      * @return mixed False on failure, or the validated addr-spec on success.
 853      */
 854     function _validateAddrSpec($addr_spec)
 855     {
 856         $addr_spec = trim($addr_spec);
 857
 858         // Split on @ sign if there is one.
 859         if (strpos($addr_spec, '@') !== false) {
 860             $parts      = explode('@', $addr_spec);
 861             $local_part = $this->_splitCheck($parts, '@');
 862             $domain     = substr($addr_spec, strlen($local_part . '@'));
 863
 864         // No @ sign so assume the default domain.
 865         } else {
 866             $local_part = $addr_spec;
 867             $domain     = $this->default_domain;
 868         }
 869
 870         if (($local_part = $this->_validateLocalPart($local_part)) === false) return false;
 871         if (($domain     = $this->_validateDomain($domain)) === false) return false;
 872
 873         // Got here so return successful.
 874         return array('local_part' => $local_part, 'domain' => $domain);
 875     }
 876
 877     /**
 878      * Function to validate the local part of an address:
 879      *   local-part = word *("." word)
 880      *
 881      * @access private
 882      * @param string $local_part
 883      * @return mixed False on failure, or the validated local part on success.
 884      */
 885     function _validateLocalPart($local_part)
 886     {
 887         $parts = explode('.', $local_part);
 888         $words = array();
 889
 890         // Split the local_part into words.
 891         while (count($parts) > 0){
 892             $words[] = $this->_splitCheck($parts, '.');
 893             for ($i = 0; $i < $this->index + 1; $i++) {
 894                 array_shift($parts);
 895             }
 896         }
 897
 898         // Validate each word.
 899         foreach ($words as $word) {
 900             // If this word contains an unquoted space, it is invalid. (6.2.4)
 901             if (strpos($word, ' ') && $word[0] !== '"')
 902             {
 903                 return false;
 904             }
 905
 906             if ($this->_validatePhrase(trim($word)) === false) return false;
 907         }
 908
 909         // Managed to get here, so return the input.
 910         return $local_part;
 911     }
 912
 913     /**
 914      * Returns an approximate count of how many addresses are in the
 915      * given string. This is APPROXIMATE as it only splits based on a
 916      * comma which has no preceding backslash. Could be useful as
 917      * large amounts of addresses will end up producing *large*
 918      * structures when used with parseAddressList().
 919      *
 920      * @param  string $data Addresses to count
 921      * @return int          Approximate count
 922      */
 923     function approximateCount($data)
 924     {
 925         return count(preg_split('/(?<!\\\\),/', $data));
 926     }
 927
 928     /**
 929      * This is a email validating function separate to the rest of the
 930      * class. It simply validates whether an email is of the common
 931      * internet form: <user>@<domain>. This can be sufficient for most
 932      * people. Optional stricter mode can be utilised which restricts
 933      * mailbox characters allowed to alphanumeric, full stop, hyphen
 934      * and underscore.
 935      *
 936      * @param  string  $data   Address to check
 937      * @param  boolean $strict Optional stricter mode
 938      * @return mixed           False if it fails, an indexed array
 939      *                         username/domain if it matches
 940      */
 941     function isValidInetAddress($data, $strict = false)
 942     {
 943         $regex = $strict ? '/^([.0-9a-z_+-]+)@(([0-9a-z-]+\.)+[0-9a-z]{2,})$/i' : '/^([*+!.&#$|\'\\%\/0-9a-z^_`{}=?~:-]+)@(([0-9a-z-]+\.)+[0-9a-z]{2,})$/i';
 944         if (preg_match($regex, trim($data), $matches)) {
 945             return array($matches[1], $matches[2]);
 946         } else {
 947             return false;
 948         }
 949     }
 950
 951 }