include/lib/swiftmailer/classes/Swift/Signers/DKIMSigner.php
<?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.
*/
/**
* DKIM Signer used to apply DKIM Signature to a message
*
* @package Swift
* @subpackage Signatures
* @author Xavier De Cock <xdecock@gmail.com>
*/
class Swift_Signers_DKIMSigner implements Swift_Signers_HeaderSigner
{
/**
* PrivateKey
*
* @var string
*/
protected $_privateKey;
/**
* DomainName
*
* @var string
*/
protected $_domainName;
/**
* Selector
*
* @var string
*/
protected $_selector;
/**
* Hash algorithm used
*
* @var string
*/
protected $_hashAlgorithm = 'rsa-sha1';
/**
* Body canon method
*
* @var string
*/
protected $_bodyCanon = 'simple';
/**
* Header canon method
*
* @var string
*/
protected $_headerCanon = 'simple';
/**
* Headers not being signed
*
* @var array
*/
protected $_ignoredHeaders = array();
/**
* Signer identity
*
* @var unknown_type
*/
protected $_signerIdentity;
/**
* BodyLength
*
* @var int
*/
protected $_bodyLen = 0;
/**
* Maximum signedLen
*
* @var int
*/
protected $_maxLen = PHP_INT_MAX;
/**
* Embbed bodyLen in signature
*
* @var boolean
*/
protected $_showLen = false;
/**
* When the signature has been applied (true means time()), false means not embedded
*
* @var mixed
*/
protected $_signatureTimestamp = true;
/**
* When will the signature expires false means not embedded, if sigTimestamp is auto
* Expiration is relative, otherwhise it's absolute
*
* @var int
*/
protected $_signatureExpiration = false;
/**
* Must we embed signed headers?
*
* @var boolean
*/
protected $_debugHeaders = false;
// work variables
/**
* Headers used to generate hash
*
* @var array
*/
protected $_signedHeaders = array();
/**
* If debugHeaders is set store debugDatas here
*
* @var string
*/
private $_debugHeadersData = '';
/**
* Stores the bodyHash
*
* @var string
*/
private $_bodyHash = '';
/**
* Stores the signature header
*
* @var Swift_Mime_Headers_ParameterizedHeader
*/
protected $_dkimHeader;
/**
* Hash Handler
*
* @var hash_ressource
*/
private $_headerHashHandler;
private $_bodyHashHandler;
private $_headerHash;
private $_headerCanonData = '';
private $_bodyCanonEmptyCounter = 0;
private $_bodyCanonIgnoreStart = 2;
private $_bodyCanonSpace = false;
private $_bodyCanonLastChar = null;
private $_bodyCanonLine = '';
private $_bound = array();
/**
* Constructor
*
* @param string $privateKey
* @param string $domainName
* @param string $selector
*/
public function __construct($privateKey, $domainName, $selector)
{
$this->_privateKey = $privateKey;
$this->_domainName = $domainName;
$this->_signerIdentity = '@' . $domainName;
$this->_selector = $selector;
}
/**
* Instanciate DKIMSigner
*
* @param string $privateKey
* @param string $domainName
* @param string $selector
* @return Swift_Signers_DKIMSigner
*/
public static function newInstance($privateKey, $domainName, $selector)
{
return new static($privateKey, $domainName, $selector);
}
/**
* Reset the Signer
* @see Swift_Signer::reset()
*/
public function reset()
{
$this->_headerHash = null;
$this->_signedHeaders = array();
$this->_headerHashHandler = null;
$this->_bodyHash = null;
$this->_bodyHashHandler = null;
$this->_bodyCanonIgnoreStart = 2;
$this->_bodyCanonEmptyCounter = 0;
$this->_bodyCanonLastChar = NULL;
$this->_bodyCanonSpace = false;
}
/**
* Writes $bytes to the end of the stream.
*
* Writing may not happen immediately if the stream chooses to buffer. If
* you want to write these bytes with immediate effect, call {@link commit()}
* after calling write().
*
* This method returns the sequence ID of the write (i.e. 1 for first, 2 for
* second, etc etc).
*
* @param string $bytes
* @return int
* @throws Swift_IoException
*/
public function write($bytes)
{
$this->_canonicalizeBody($bytes);
foreach ($this->_bound as $is) {
$is->write($bytes);
}
}
/**
* For any bytes that are currently buffered inside the stream, force them
* off the buffer.
*
* @throws Swift_IoException
*/
public function commit()
{
// Nothing to do
return;
}
/**
* Attach $is to this stream.
* The stream acts as an observer, receiving all data that is written.
* All {@link write()} and {@link flushBuffers()} operations will be mirrored.
*
* @param Swift_InputByteStream $is
*/
public function bind(Swift_InputByteStream $is)
{
// Don't have to mirror anything
$this->_bound[] = $is;
return;
}
/**
* Remove an already bound stream.
* If $is is not bound, no errors will be raised.
* If the stream currently has any buffered data it will be written to $is
* before unbinding occurs.
*
* @param Swift_InputByteStream $is
*/
public function unbind(Swift_InputByteStream $is)
{
// Don't have to mirror anything
foreach ($this->_bound as $k => $stream) {
if ($stream === $is) {
unset($this->_bound[$k]);
return;
}
}
return;
}
/**
* Flush the contents of the stream (empty it) and set the internal pointer
* to the beginning.
*
* @throws Swift_IoException
*/
public function flushBuffers()
{
$this->reset();
}
/**
* Set hash_algorithm, must be one of rsa-sha256 | rsa-sha1 defaults to rsa-sha256
*
* @param string $hash
* @return Swift_Signers_DKIMSigner
*/
public function setHashAlgorithm($hash)
{
// Unable to sign with rsa-sha256
if ($hash == 'rsa-sha1') {
$this->_hashAlgorithm = 'rsa-sha1';
} else {
$this->_hashAlgorithm = 'rsa-sha256';
}
return $this;
}
/**
* Set the body canonicalization algorithm
*
* @param string $canon
* @return Swift_Signers_DKIMSigner
*/
public function setBodyCanon($canon)
{
if ($canon == 'relaxed') {
$this->_bodyCanon = 'relaxed';
} else {
$this->_bodyCanon = 'simple';
}
return $this;
}
/**
* Set the header canonicalization algorithm
*
* @param string $canon
* @return Swift_Signers_DKIMSigner
*/
public function setHeaderCanon($canon)
{
if ($canon == 'relaxed') {
$this->_headerCanon = 'relaxed';
} else {
$this->_headerCanon = 'simple';
}
return $this;
}
/**
* Set the signer identity
*
* @param string $identity
* @return Swift_Signers_DKIMSigner
*/
public function setSignerIdentity($identity)
{
$this->_signerIdentity = $identity;
return $this;
}
/**
* Set the length of the body to sign
*
* @param mixed $len (bool or int)
* @return Swift_Signers_DKIMSigner
*/
public function setBodySignedLen($len)
{
if ($len === true) {
$this->_showLen = true;
$this->_maxLen = PHP_INT_MAX;
} elseif ($len === false) {
$this->showLen = false;
$this->_maxLen = PHP_INT_MAX;
} else {
$this->_showLen = true;
$this->_maxLen = (int) $len;
}
return $this;
}
/**
* Set the signature timestamp
*
* @param timestamp $time
* @return Swift_Signers_DKIMSigner
*/
public function setSignatureTimestamp($time)
{
$this->_signatureTimestamp = $time;
return $this;
}
/**
* Set the signature expiration timestamp
*
* @param timestamp $time
* @return Swift_Signers_DKIMSigner
*/
public function setSignatureExpiration($time)
{
$this->_signatureExpiration = $time;
return $this;
}
/**
* Enable / disable the DebugHeaders
*
* @param boolean $debug
* @return Swift_Signers_DKIMSigner
*/
public function setDebugHeaders($debug)
{
$this->_debugHeaders = (bool) $debug;
return $this;
}
/**
* Start Body
*
*/
public function startBody()
{
// Init
switch ($this->_hashAlgorithm) {
case 'rsa-sha256' :
$this->_bodyHashHandler = hash_init('sha256');
break;
case 'rsa-sha1' :
$this->_bodyHashHandler = hash_init('sha1');
break;
}
$this->_bodyCanonLine = '';
}
/**
* End Body
*
*/
public function endBody()
{
$this->_endOfBody();
}
/**
* Returns the list of Headers Tampered by this plugin
*
* @return array
*/
public function getAlteredHeaders()
{
if ($this->_debugHeaders) {
return array('DKIM-Signature', 'X-DebugHash');
} else {
return array('DKIM-Signature');
}
}
/**
* Adds an ignored Header
*
* @param string $header_name
* @return Swift_Signers_DKIMSigner
*/
public function ignoreHeader($header_name)
{
$this->_ignoredHeaders[strtolower($header_name)] = true;
return $this;
}
/**
* Set the headers to sign
*
* @param Swift_Mime_HeaderSet $headers
* @return Swift_Signers_DKIMSigner
*/
public function setHeaders(Swift_Mime_HeaderSet $headers)
{
$this->_headerCanonData = '';
// Loop through Headers
$listHeaders = $headers->listAll();
foreach ($listHeaders as $hName) {
// Check if we need to ignore Header
if (! isset($this->_ignoredHeaders[strtolower($hName)])) {
if ($headers->has($hName)) {
$tmp = $headers->getAll($hName);
foreach ($tmp as $header) {
if ($header->getFieldBody() != '') {
$this->_addHeader($header->toString());
$this->_signedHeaders[] = $header->getFieldName();
}
}
}
}
}
return $this;
}
/**
* Add the signature to the given Headers
*
* @param Swift_Mime_HeaderSet $headers
* @return Swift_Signers_DKIMSigner
*/
public function addSignature(Swift_Mime_HeaderSet $headers)
{
// Prepare the DKIM-Signature
$params = array('v' => '1', 'a' => $this->_hashAlgorithm, 'bh' => base64_encode($this->_bodyHash), 'd' => $this->_domainName, 'h' => implode(': ', $this->_signedHeaders), 'i' => $this->_signerIdentity, 's' => $this->_selector);
if ($this->_bodyCanon != 'simple') {
$params['c'] = $this->_headerCanon . '/' . $this->_bodyCanon;
} elseif ($this->_headerCanon != 'simple') {
$params['c'] = $this->_headerCanon;
}
if ($this->_showLen) {
$params['l'] = $this->_bodyLen;
}
if ($this->_signatureTimestamp === true) {
$params['t'] = time();
if ($this->_signatureExpiration !== false) {
$params['x'] = $params['t'] + $this->_signatureExpiration;
}
} else {
if ($this->_signatureTimestamp !== false) {
$params['t'] = $this->_signatureTimestamp;
}
if ($this->_signatureExpiration !== false) {
$params['x'] = $this->_signatureExpiration;
}
}
if ($this->_debugHeaders) {
$params['z'] = implode('|', $this->_debugHeadersData);
}
$string = '';
foreach ($params as $k => $v) {
$string .= $k . '=' . $v . '; ';
}
$string = trim($string);
$headers->addTextHeader('DKIM-Signature', $string);
// Add the last DKIM-Signature
$tmp = $headers->getAll('DKIM-Signature');
$this->_dkimHeader = end($tmp);
$this->_addHeader(trim($this->_dkimHeader->toString()) . "\r\n b=", true);
$this->_endOfHeaders();
if ($this->_debugHeaders) {
$headers->addTextHeader('X-DebugHash', base64_encode($this->_headerHash));
}
$this->_dkimHeader->setValue($string . " b=" . trim(chunk_split(base64_encode($this->_getEncryptedHash()), 73, " ")));
return $this;
}
/* Private helpers */
protected function _addHeader($header, $is_sig = false)
{
switch ($this->_headerCanon) {
case 'relaxed' :
// Prepare Header and cascade
$exploded = explode(':', $header, 2);
$name = strtolower(trim($exploded[0]));
$value = str_replace("\r\n", "", $exploded[1]);
$value = preg_replace("/[ \t][ \t]+/", " ", $value);
$header = $name . ":" . trim($value) . ($is_sig ? '' : "\r\n");
case 'simple' :
// Nothing to do
}
$this->_addToHeaderHash($header);
}
protected function _endOfHeaders()
{
//$this->_headerHash=hash_final($this->_headerHashHandler, true);
}
protected function _canonicalizeBody($string)
{
$len = strlen($string);
$canon = '';
$method = ($this->_bodyCanon == "relaxed");
for ($i = 0; $i < $len; ++$i) {
if ($this->_bodyCanonIgnoreStart > 0) {
--$this->_bodyCanonIgnoreStart;
continue;
}
switch ($string[$i]) {
case "\r" :
$this->_bodyCanonLastChar = "\r";
break;
case "\n" :
if ($this->_bodyCanonLastChar == "\r") {
if ($method) {
$this->_bodyCanonSpace = false;
}
if ($this->_bodyCanonLine == '') {
++$this->_bodyCanonEmptyCounter;
} else {
$this->_bodyCanonLine = '';
$canon .= "\r\n";
}
} else {
// Wooops Error
// todo handle it but should never happen
}
break;
case " " :
case "\t" :
if ($method) {
$this->_bodyCanonSpace = true;
break;
}
default :
if ($this->_bodyCanonEmptyCounter > 0) {
$canon .= str_repeat("\r\n", $this->_bodyCanonEmptyCounter);
$this->_bodyCanonEmptyCounter = 0;
}
if ($this->_bodyCanonSpace) {
$this->_bodyCanonLine .= ' ';
$canon .= ' ';
$this->_bodyCanonSpace = false;
}
$this->_bodyCanonLine .= $string[$i];
$canon .= $string[$i];
}
}
$this->_addToBodyHash($canon);
}
protected function _endOfBody()
{
// Add trailing Line return if last line is non empty
if (strlen($this->_bodyCanonLine) > 0) {
$this->_addToBodyHash("\r\n");
}
$this->_bodyHash = hash_final($this->_bodyHashHandler, true);
}
private function _addToBodyHash($string)
{
$len = strlen($string);
if ($len > ($new_len = ($this->_maxLen - $this->_bodyLen))) {
$string = substr($string, 0, $new_len);
$len = $new_len;
}
hash_update($this->_bodyHashHandler, $string);
$this->_bodyLen += $len;
}
private function _addToHeaderHash($header)
{
if ($this->_debugHeaders) {
$this->_debugHeadersData[] = trim($header);
}
$this->_headerCanonData .= $header;
}
private function _getEncryptedHash()
{
$signature = '';
switch ($this->_hashAlgorithm) {
case 'rsa-sha1':
$algorithm = OPENSSL_ALGO_SHA1;
break;
case 'rsa-sha256':
$algorithm = OPENSSL_ALGO_SHA256;
break;
}
$pkeyId=openssl_get_privatekey($this->_privateKey);
if (!$pkeyId) {
throw new Swift_SwiftException('Unable to load DKIM Private Key ['.openssl_error_string().']');
}
if (openssl_sign($this->_headerCanonData, $signature, $this->_privateKey, $algorithm)) {
return $signature;
}
throw new Swift_SwiftException('Unable to sign DKIM Hash ['.openssl_error_string().']');
}
}