Swift_Signers_DKIMSigner

Complexity

Total Complexity

82

Size/Duplication

Total Lines	781
Duplicated Lines	8.19 %

Coupling/Cohesion

Components	1
Dependencies	4

Test Coverage

Coverage

68.48%

Importance

Changes

0

29 Methods

Rating	Name	Duplication	Size	Complexity
A	newInstance()	0	4	1
A	commit()	0	5	1
A	bind()	0	7	1
A	unbind()	11	11	3
A	flushBuffers()	0	4	1
A	setSignerIdentity()	0	6	1
A	setBodySignedLen()	0	15	3
A	setSignatureExpiration()	0	6	1
A	setDebugHeaders()	0	6	1
A	ignoreHeader()	0	6	1
A	_endOfHeaders()	0	3	1
A	__construct()	0	13	2
A	reset()	0	11	1
A	write()	0	7	2
A	setHashAlgorithm()	0	18	4
A	setBodyCanon()	0	10	2
A	setHeaderCanon()	0	10	2
A	setSignatureTimestamp()	0	6	1
A	startBody()	0	13	3
A	endBody()	0	4	1
A	getAlteredHeaders()	0	8	2
B	setHeaders()	16	24	6
D	addSignature()	0	68	11
A	_addHeader()	15	15	4
C	_canonicalizeBody()	22	54	13
A	_endOfBody()	0	9	2
A	_addToBodyHash()	0	11	2
A	_addToHeaderHash()	0	7	2
C	_getEncryptedHash()	0	30	7

<?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.
 *
 * @author Xavier De Cock <xdecock@gmail.com>
 */
class Swift_Signers_DKIMSigner implements Swift_Signers_HeaderSigner

PSR1 recommends that each class must be in a namespace of at least one level to avoid collisions.

{
    /**
     * PrivateKey.
     *
     * @var string
     */
    protected $_privateKey;

    /**
     * DomainName.
     *
     * @var string
     */
    protected $_domainName;

    /**
     * Selector.
     *
     * @var string
     */
    protected $_selector;

    /**
     * @var string
     */
    private $_passphrase = '';

    /**
     * Hash algorithm used.
     *
     * @see RFC6376 3.3: Signers MUST implement and SHOULD sign using rsa-sha256.
     *
     * @var string
     */
    protected $_hashAlgorithm = 'rsa-sha256';

    /**
     * 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('return-path' => true);

    /**
     * Signer identity.
     *
     * @var string
     */
    protected $_signerIdentity;

    /**
     * BodyLength.
     *
     * @var int
     */
    protected $_bodyLen = 0;

    /**
     * Maximum signedLen.
     *
     * @var int
     */
    protected $_maxLen = PHP_INT_MAX;

    /**
     * Embbed bodyLen in signature.
     *
     * @var bool
     */
    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, otherwise it's absolute.
     *
     * @var int
     */
    protected $_signatureExpiration = false;

    /**
     * Must we embed signed headers?
     *
     * @var bool
     */
    protected $_debugHeaders = false;

    // work variables
    /**
     * Headers used to generate hash.
     *
     * @var array
     */
    protected $_signedHeaders = array();

    /**
     * If debugHeaders is set store debugData here.
     *
     * @var string
     */
    private $_debugHeadersData = '';

    /**
     * Stores the bodyHash.
     *
     * @var string
     */
    private $_bodyHash = '';

    /**
     * Stores the signature header.
     *
     * @var Swift_Mime_Headers_ParameterizedHeader
     */
    protected $_dkimHeader;

    /**
     * @var resource
     */
    private $_bodyHashHandler;

    /**
     * @var null
     *
     * no used?
     */
    private $_headerHash;

    /**
     * @var string
     */
    private $_headerCanonData = '';

    /**
     * @var int
     */
    private $_bodyCanonEmptyCounter = 0;

    /**
     * @var int
     */
    private $_bodyCanonIgnoreStart = 2;

    /**
     * @var bool
     */
    private $_bodyCanonSpace = false;

    /**
     * @var null|string
     */
    private $_bodyCanonLastChar = null;

    /**
     * @var string
     */
    private $_bodyCanonLine = '';

    /**
     * @var array
     */
    private $_bound = array();

    /**
     * Constructor.
     *
     * @param string $privateKey
     * @param string $domainName
     * @param string $selector
     * @param string $passphrase
     */
    public function __construct($privateKey, $domainName, $selector, $passphrase = '')
    {
        $this->_privateKey = $privateKey;
        $this->_domainName = $domainName;
        $this->_signerIdentity = '@' . $domainName;
        $this->_selector = $selector;
        $this->_passphrase = $passphrase;

        // keep fallback hash algorithm sha1 if php version is lower than 5.4.8
        if (PHP_VERSION_ID < 50408) {
            $this->_hashAlgorithm = 'rsa-sha1';
        }
    }

    /**
     * Instanciate DKIMSigner.
     *
     * @param string $privateKey
     * @param string $domainName
     * @param string $selector
     *
     * @return self
     */
    public static function newInstance($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->_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 $bytes
     *
     * @throws Swift_IoException
     *
     * @return int
     */
    // TODO: fix return
    public function write($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.
     */
    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)

This method seems to be duplicated in your project.

    {
        // Don't have to mirror anything
        foreach ($this->_bound as $k => $stream) {
            if ($stream === $is) {
                unset($this->_bound[$k]);

                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.
     *
     * @param string $hash 'rsa-sha1' or 'rsa-sha256'
     *
     * @throws Swift_SwiftException
     *
     * @return $this
     */
    public function setHashAlgorithm($hash)
    {
        switch ($hash) {
            case 'rsa-sha1':
                $this->_hashAlgorithm = 'rsa-sha1';
                break;
            case 'rsa-sha256':
                $this->_hashAlgorithm = 'rsa-sha256';
                if (!defined('OPENSSL_ALGO_SHA256')) {
                    throw new Swift_SwiftException('Unable to set sha256 as it is not supported by OpenSSL.');
                }
                break;
            default:
                throw new Swift_SwiftException('Unable to set the hash algorithm, must be one of rsa-sha1 or rsa-sha256 (%s given).', $hash);
        }

        return $this;
    }

    /**
     * Set the body canonicalization algorithm.
     *
     * @param string $canon
     *
     * @return $this
     */
    public function setBodyCanon($canon)
    {
        if ($canon === 'relaxed') {
            $this->_bodyCanon = 'relaxed';
        } else {
            $this->_bodyCanon = 'simple';
        }

        return $this;
    }

    /**
     * Set the header canonicalization algorithm.
     *
     * @param string $canon
     *
     * @return $this
     */
    public function setHeaderCanon($canon)
    {
        if ($canon === 'relaxed') {
            $this->_headerCanon = 'relaxed';
        } else {
            $this->_headerCanon = 'simple';
        }

        return $this;
    }

    /**
     * Set the signer identity.
     *
     * @param string $identity
     *
     * @return $this
     */
    public function setSignerIdentity($identity)
    {
        $this->_signerIdentity = $identity;

        return $this;
    }

    /**
     * Set the length of the body to sign.
     *
     * @param mixed $len (bool or int)
     *
     * @return $this
     */
    public function setBodySignedLen($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 int $time A timestamp
     *
     * @return $this
     */
    public function setSignatureTimestamp($time)
    {
        $this->_signatureTimestamp = $time;

        return $this;
    }

    /**
     * Set the signature expiration timestamp.
     *
     * @param int $time A timestamp
     *
     * @return $this
     */
    public function setSignatureExpiration($time)
    {
        $this->_signatureExpiration = $time;

        return $this;
    }

    /**
     * Enable / disable the DebugHeaders.
     *
     * @param bool $debug
     *
     * @return Swift_Signers_DKIMSigner
     */
    public function setDebugHeaders($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 string[]
     */
    public function getAlteredHeaders()
    {
        if ($this->_debugHeaders) {
            return array('DKIM-Signature', 'X-DebugHash');
        }

      return array('DKIM-Signature');
    }

    /**
     * Adds an ignored Header.
     *
     * @param string $header_name
     *
     * @return Swift_Signers_DKIMSigner
     */
    public function ignoreHeader($header_name)
    {
        $this->_ignoredHeaders[Swift::strtolowerWithStaticCache($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) {

This code seems to be duplicated across your project.

            // Check if we need to ignore Header
            if (
                !isset($this->_ignoredHeaders[Swift::strtolowerWithStaticCache($hName)])
                &&
                $headers->has($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);

It seems like end($tmp) of type object<Swift_Mime_Headers_AbstractHeader> or false is incompatible with the declared type object<Swift_Mime_Headers_ParameterizedHeader> of property $_dkimHeader.

        $this->_addHeader(trim($this->_dkimHeader->toString()) . "\r\n b=", true);
        $this->_endOfHeaders();

The method Swift_Signers_DKIMSigner::_endOfHeaders() has been deprecated with message: This method is currently useless in this class but it must be kept for BC reasons due to its "protected" scope. This method might be overridden by custom client code.

        if ($this->_debugHeaders) {
            $headers->addTextHeader('X-DebugHash', base64_encode($this->_headerHash));
        }

        $this->_dkimHeader->setValue($string . ' b=' . trim(chunk_split(base64_encode($this->_getEncryptedHash()), 73, ' ')));

It seems like you code against a specific sub-type and not the parent class Swift_Mime_Headers_AbstractHeader as the method setValue() does only exist in the following sub-classes of Swift_Mime_Headers_AbstractHeader: Swift_Mime_Headers_ParameterizedHeader, Swift_Mime_Headers_UnstructuredHeader. Maybe you want to instanceof check for one of these explicitly?

        return $this;
    }

    /**
     * @param string $header
     * @param bool   $is_sig
     */
    protected function _addHeader($header, $is_sig = false)

This method seems to be duplicated in your project.

    {
        switch ($this->_headerCanon) {
            case 'relaxed':

There must be a comment when fall-through is intentional in a non-empty case body

                // Prepare Header and cascade
                $exploded = explode(':', $header, 2);
                $name = Swift::strtolowerWithStaticCache(trim($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);
    }

    /**
     * @deprecated This method is currently useless in this class but it must be
     *             kept for BC reasons due to its "protected" scope. This method
     *             might be overridden by custom client code.
     */
    protected function _endOfHeaders()
    {
    }

    /**
     * @param string $string
     */
    protected function _canonicalizeBody($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":

This code seems to be duplicated across your project.

                    if ($this->_bodyCanonLastChar === "\r") {
                        if ($method) {
                            $this->_bodyCanonSpace = false;
                        }

                        if ($this->_bodyCanonLine === '') {
                            ++$this->_bodyCanonEmptyCounter;
                        } else {
                            $this->_bodyCanonLine = '';
                            $canon .= "\r\n";
                        }

                    } else {

This else statement is empty and can be removed.

                        // Wooops Error
                        // TODO: handle it but should never happen
                    }
                    break;
                case ' ':
                case "\t":

There must be a comment when fall-through is intentional in a non-empty case body

                    if ($method) {
                        $this->_bodyCanonSpace = true;
                        break;
                    }
                default:
                    if ($this->_bodyCanonEmptyCounter > 0) {

This code seems to be duplicated across your project.

                        $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 ($this->_bodyCanonLine !== '') {
            $this->_addToBodyHash("\r\n");
        }

        $this->_bodyHash = hash_final($this->_bodyHashHandler, true);
    }

    /**
     * @param string $string
     */
    private function _addToBodyHash($string)
    {
        $len = strlen($string);
        if ($len > ($new_len = ($this->_maxLen - $this->_bodyLen))) {
          /** @noinspection CallableParameterUseCaseInTypeContextInspection */
          $string = substr($string, 0, $new_len);
            $len = $new_len;
        }
        hash_update($this->_bodyHashHandler, $string);
        $this->_bodyLen += $len;
    }

    /**
     * @param string $header
     */
    private function _addToHeaderHash($header)
    {
        if ($this->_debugHeaders) {
            $this->_debugHeadersData[] = trim($header);
        }
        $this->_headerCanonData .= $header;
    }

    /**
     * @throws Swift_SwiftException
     *
     * @return string
     */
    private function _getEncryptedHash()
    {
        $signature = '';

        switch ($this->_hashAlgorithm) {
            case 'rsa-sha1':
                $algorithm = OPENSSL_ALGO_SHA1;
                break;
            case 'rsa-sha256':
                $algorithm = OPENSSL_ALGO_SHA256;
                break;
            default:
                $algorithm = PHP_VERSION_ID < 50408 ? OPENSSL_ALGO_SHA1 : OPENSSL_ALGO_SHA256;
        }

        if ($this->_passphrase) {
          $pkeyId = openssl_get_privatekey($this->_privateKey, $this->_passphrase);
        } else {
          $pkeyId = openssl_get_privatekey($this->_privateKey);
        }
        if (!$pkeyId) {
            throw new Swift_SwiftException('Unable to load DKIM Private Key [' . openssl_error_string() . ']');
        }

        if (openssl_sign($this->_headerCanonData, $signature, $pkeyId, $algorithm)) {
            return $signature;
        }

        throw new Swift_SwiftException('Unable to sign DKIM Hash [' . openssl_error_string() . ']');
    }
}