CRM/Utils/Verp.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | Copyright CiviCRM LLC. All rights reserved.                        |
   5  |                                                                    |
   6  | This work is published under the GNU AGPLv3 license with some      |
   7  | permitted exceptions and without any warranty. For full license    |
   8  | and copyright information, see https://civicrm.org/licensing       |
   9  +--------------------------------------------------------------------+
  10  */
  11
  12 /**
  13  * Class to handle encoding and decoding Variable Enveleope Return Path (VERP)
  14  * headers.
  15  *
  16  * @package CRM
  17  * @copyright CiviCRM LLC https://civicrm.org/licensing
  18  */
  19 class CRM_Utils_Verp {
  20   /**
  21    * Mapping of reserved characters to hex codes
  22    * @var array
  23    */
  24   public static $encodeMap = [
  25     '+' => '2B',
  26     '@' => '40',
  27     ':' => '3A',
  28     '%' => '25',
  29     '!' => '21',
  30     '-' => '2D',
  31     '[' => '5B',
  32     ']' => '5D',
  33   ];
  34
  35   /**
  36    * Mapping of hex codes to reserved characters
  37    * @var array
  38    */
  39   public static $decodeMap = [
  40     '40' => '@',
  41     '3A' => ':',
  42     '25' => '%',
  43     '21' => '!',
  44     '2D' => '-',
  45     '5B' => '[',
  46     '5D' => ']',
  47     '2B' => '+',
  48   ];
  49
  50   /**
  51    * Encode the sender's address with the VERPed recipient.
  52    *
  53    * @param string $sender
  54    *   The address of the sender.
  55    * @param string $recipient
  56    *   The address of the recipient.
  57    *
  58    * @return string
  59    *   The VERP encoded address
  60    */
  61   public static function encode($sender, $recipient) {
  62     preg_match('/(.+)\@([^\@]+)$/', $sender, $match);
  63     $slocal = $match[1];
  64     $sdomain = $match[2];
  65
  66     preg_match('/(.+)\@([^\@]+)$/', $recipient, $match);
  67     $rlocal = $match[1] ?? NULL;
  68     $rdomain = $match[2] ?? NULL;
  69
  70     foreach (self::$encodeMap as $char => $code) {
  71       $rlocal = preg_replace('/' . preg_quote($char) . '/i', "+$code", $rlocal);
  72       $rdomain = preg_replace('/' . preg_quote($char) . '/i', "+$code", $rdomain);
  73     }
  74
  75     return "$slocal-$rlocal=$rdomain@$sdomain";
  76   }
  77
  78   /**
  79    * Decode the address and return the sender and recipient as an array.
  80    *
  81    * @param string $address
  82    *   The address to be decoded.
  83    *
  84    * @return array
  85    *   The tuple ($sender, $recipient)
  86    */
  87   public static function &verpdecode($address) {
  88     preg_match('/^(.+)-([^=]+)=([^\@]+)\@(.+)/', $address, $match);
  89
  90     $slocal = $match[1];
  91     $rlocal = $match[2];
  92     $rdomain = $match[3];
  93     $sdomain = $match[4];
  94
  95     foreach (self::$decodeMap as $code => $char) {
  96       $rlocal = preg_replace("/+$code/i", $char, $rlocal);
  97       $rdomain = preg_replace("/+$code/i", $char, $rdomain);
  98     }
  99
 100     return ["$slocal@$sdomain", "$rlocal@$rdomain"];
 101   }
 102
 103 }