<?php
/*
* This file is part of SwiftMailer.
* (c) 2004-2009 Chris Corbyn
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
/**
* Defines the grammar to use for validation, implements the RFC 2822 (and friends) ABNF grammar definitions.
*
* @author Fabien Potencier
* @author Chris Corbyn
*/
class Swift_Mime_Grammar
{
/**
* Special characters used in the syntax which need to be escaped.
*
* @var string[]
*/
private static $_specials = array();
/**
* Tokens defined in RFC 2822 (and some related RFCs).
*
* @var string[]
*/
private static $_grammar = array();
/**
* Initialize some RFC 2822 (and friends) ABNF grammar definitions.
*/
public function __construct()
{
$this->init();
}
public function __wakeup()
{
$this->init();
}
protected function init()
{
if (count(self::$_specials) > 0) {
return;
}
self::$_specials = array(
'(', ')', '<', '>', '[', ']',
':', ';', '@', ',', '.', '"',
);
/*** Refer to RFC 2822 for ABNF grammar ***/
// All basic building blocks
self::$_grammar['NO-WS-CTL'] = '[\x01-\x08\x0B\x0C\x0E-\x19\x7F]';
self::$_grammar['WSP'] = '[ \t]';
self::$_grammar['CRLF'] = '(?:\r\n)';
self::$_grammar['FWS'] = '(?:(?:'.self::$_grammar['WSP'].'*'.
self::$_grammar['CRLF'].')?'.self::$_grammar['WSP'].')';
self::$_grammar['text'] = '[\x00-\x08\x0B\x0C\x0E-\x7F]';
self::$_grammar['quoted-pair'] = '(?:\\\\'.self::$_grammar['text'].')';
self::$_grammar['ctext'] = '(?:'.self::$_grammar['NO-WS-CTL'].
'|[\x21-\x27\x2A-\x5B\x5D-\x7E])';
// Uses recursive PCRE (?1) -- could be a weak point??
self::$_grammar['ccontent'] = '(?:'.self::$_grammar['ctext'].'|'.
self::$_grammar['quoted-pair'].'|(?1))';
self::$_grammar['comment'] = '(\((?:'.self::$_grammar['FWS'].'|'.
self::$_grammar['ccontent'].')*'.self::$_grammar['FWS'].'?\))';
self::$_grammar['CFWS'] = '(?:(?:'.self::$_grammar['FWS'].'?'.
self::$_grammar['comment'].')*(?:(?:'.self::$_grammar['FWS'].'?'.
self::$_grammar['comment'].')|'.self::$_grammar['FWS'].'))';
self::$_grammar['qtext'] = '(?:'.self::$_grammar['NO-WS-CTL'].
'|[\x21\x23-\x5B\x5D-\x7E])';
self::$_grammar['qcontent'] = '(?:'.self::$_grammar['qtext'].'|'.
self::$_grammar['quoted-pair'].')';
self::$_grammar['quoted-string'] = '(?:'.self::$_grammar['CFWS'].'?"'.
'('.self::$_grammar['FWS'].'?'.self::$_grammar['qcontent'].')*'.
self::$_grammar['FWS'].'?"'.self::$_grammar['CFWS'].'?)';
self::$_grammar['atext'] = '[a-zA-Z0-9!#\$%&\'\*\+\-\/=\?\^_`\{\}\|~]';
self::$_grammar['atom'] = '(?:'.self::$_grammar['CFWS'].'?'.
self::$_grammar['atext'].'+'.self::$_grammar['CFWS'].'?)';
self::$_grammar['dot-atom-text'] = '(?:'.self::$_grammar['atext'].'+'.
'(\.'.self::$_grammar['atext'].'+)*)';
self::$_grammar['dot-atom'] = '(?:'.self::$_grammar['CFWS'].'?'.
self::$_grammar['dot-atom-text'].'+'.self::$_grammar['CFWS'].'?)';
self::$_grammar['word'] = '(?:'.self::$_grammar['atom'].'|'.
self::$_grammar['quoted-string'].')';
self::$_grammar['phrase'] = '(?:'.self::$_grammar['word'].'+?)';
self::$_grammar['no-fold-quote'] = '(?:"(?:'.self::$_grammar['qtext'].
'|'.self::$_grammar['quoted-pair'].')*")';
self::$_grammar['dtext'] = '(?:'.self::$_grammar['NO-WS-CTL'].
'|[\x21-\x5A\x5E-\x7E])';
self::$_grammar['no-fold-literal'] = '(?:\[(?:'.self::$_grammar['dtext'].
'|'.self::$_grammar['quoted-pair'].')*\])';
// Message IDs
self::$_grammar['id-left'] = '(?:'.self::$_grammar['dot-atom-text'].'|'.
self::$_grammar['no-fold-quote'].')';
self::$_grammar['id-right'] = '(?:'.self::$_grammar['dot-atom-text'].'|'.
self::$_grammar['no-fold-literal'].')';
// Addresses, mailboxes and paths
self::$_grammar['local-part'] = '(?:'.self::$_grammar['dot-atom'].'|'.
self::$_grammar['quoted-string'].')';
self::$_grammar['dcontent'] = '(?:'.self::$_grammar['dtext'].'|'.
self::$_grammar['quoted-pair'].')';
self::$_grammar['domain-literal'] = '(?:'.self::$_grammar['CFWS'].'?\[('.
self::$_grammar['FWS'].'?'.self::$_grammar['dcontent'].')*?'.
self::$_grammar['FWS'].'?\]'.self::$_grammar['CFWS'].'?)';
self::$_grammar['domain'] = '(?:'.self::$_grammar['dot-atom'].'|'.
self::$_grammar['domain-literal'].')';
self::$_grammar['addr-spec'] = '(?:'.self::$_grammar['local-part'].'@'.
self::$_grammar['domain'].')';
}
/**
* Get the grammar defined for $name token.
*
* @param string $name exactly as written in the RFC
*
* @return string
*/
public function getDefinition($name)
{
if (array_key_exists($name, self::$_grammar)) {
return self::$_grammar[$name];
}
throw new Swift_RfcComplianceException(
"No such grammar '".$name."' defined."
);
}
/**
* Returns the tokens defined in RFC 2822 (and some related RFCs).
*
* @return array
*/
public function getGrammarDefinitions()
{
return self::$_grammar;
}
/**
* Returns the current special characters used in the syntax which need to be escaped.
*
* @return array
*/
public function getSpecials()
{
return self::$_specials;
}
/**
* Escape special characters in a string (convert to quoted-pairs).
*
* @param string $token
* @param string[] $include additional chars to escape
* @param string[] $exclude chars from escaping
*
* @return string
*/
public function escapeSpecials($token, $include = array(), $exclude = array())
{
foreach (array_merge(array('\\'), array_diff(self::$_specials, $exclude), $include) as $char) {
$token = str_replace($char, '\\'.$char, $token);
}
return $token;
}
}