<?php
/**
* Zend Framework
*
* LICENSE
*
* This source file is subject to the new BSD license that is bundled
* with this package in the file LICENSE.txt.
* It is also available through the world-wide-web at this URL:
* http://framework.zend.com/license/new-bsd
* If you did not receive a copy of the license and are unable to
* obtain it through the world-wide-web, please send an email
* to license@zend.com so we can send you a copy immediately.
*
* @category Zend
* @package Zend_InfoCard
* @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
* @version $Id: InfoCard.php 24593 2012-01-05 20:35:02Z matthew $
*/
/**
* Zend_InfoCard_Xml_EncryptedData
*/
require_once 'Zend/InfoCard/Xml/EncryptedData.php';
/**
* Zend_InfoCard_Xml_Assertion
*/
require_once 'Zend/InfoCard/Xml/Assertion.php';
/**
* Zend_InfoCard_Cipher
*/
require_once 'Zend/InfoCard/Cipher.php';
/**
* Zend_InfoCard_Xml_Security
*/
require_once 'Zend/InfoCard/Xml/Security.php';
/**
* Zend_InfoCard_Adapter_Interface
*/
require_once 'Zend/InfoCard/Adapter/Interface.php';
/**
* Zend_InfoCard_Claims
*/
require_once 'Zend/InfoCard/Claims.php';
/**
* @category Zend
* @package Zend_InfoCard
* @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
class Zend_InfoCard
{
/**
* URI for XML Digital Signature SHA1 Digests
*/
const DIGEST_SHA1 = 'http://www.w3.org/2000/09/xmldsig#sha1';
/**
* An array of certificate pair files and optional passwords for them to search
* when trying to determine which certificate was used to encrypt the transient key
*
* @var Array
*/
protected $_keyPairs;
/**
* The instance to use to decrypt public-key encrypted data
*
* @var Zend_InfoCard_Cipher_Pki_Interface
*/
protected $_pkiCipherObj;
/**
* The instance to use to decrypt symmetric encrypted data
*
* @var Zend_InfoCard_Cipher_Symmetric_Interface
*/
protected $_symCipherObj;
/**
* The InfoCard Adapter to use for callbacks into the application using the component
* such as when storing assertions, etc.
*
* @var Zend_InfoCard_Adapter_Interface
*/
protected $_adapter;
/**
* InfoCard Constructor
*
* @throws Zend_InfoCard_Exception
*/
public function __construct()
{
$this->_keyPairs = array();
if(!extension_loaded('mcrypt')) {
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Use of the Zend_InfoCard component requires the mcrypt extension to be enabled in PHP");
}
if(!extension_loaded('openssl')) {
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Use of the Zend_InfoCard component requires the openssl extension to be enabled in PHP");
}
}
/**
* Sets the adapter uesd for callbacks into the application using the component, used
* when doing things such as storing / retrieving assertions, etc.
*
* @param Zend_InfoCard_Adapter_Interface $a The Adapter instance
* @return Zend_InfoCard The instnace
*/
public function setAdapter(Zend_InfoCard_Adapter_Interface $a)
{
$this->_adapter = $a;
return $this;
}
/**
* Retrieves the adapter used for callbacks into the application using the component.
* If no adapter was set then an instance of Zend_InfoCard_Adapter_Default is used
*
* @return Zend_InfoCard_Adapter_Interface The Adapter instance
*/
public function getAdapter()
{
if($this->_adapter === null) {
require_once 'Zend/InfoCard/Adapter/Default.php';
$this->setAdapter(new Zend_InfoCard_Adapter_Default());
}
return $this->_adapter;
}
/**
* Gets the Public Key Cipher object used in this instance
*
* @return Zend_InfoCard_Cipher_Pki_Interface
*/
public function getPkiCipherObject()
{
return $this->_pkiCipherObj;
}
/**
* Sets the Public Key Cipher Object used in this instance
*
* @param Zend_InfoCard_Cipher_Pki_Interface $cipherObj
* @return Zend_InfoCard
*/
public function setPkiCipherObject(Zend_InfoCard_Cipher_Pki_Interface $cipherObj)
{
$this->_pkiCipherObj = $cipherObj;
return $this;
}
/**
* Get the Symmetric Cipher Object used in this instance
*
* @return Zend_InfoCard_Cipher_Symmetric_Interface
*/
public function getSymCipherObject()
{
return $this->_symCipherObj;
}
/**
* Sets the Symmetric Cipher Object used in this instance
*
* @param Zend_InfoCard_Cipher_Symmetric_Interface $cipherObj
* @return Zend_InfoCard
*/
public function setSymCipherObject($cipherObj)
{
$this->_symCipherObj = $cipherObj;
return $this;
}
/**
* Remove a Certificate Pair by Key ID from the search list
*
* @throws Zend_InfoCard_Exception
* @param string $key_id The Certificate Key ID returned from adding the certificate pair
* @return Zend_InfoCard
*/
public function removeCertificatePair($key_id)
{
if(!key_exists($key_id, $this->_keyPairs)) {
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Attempted to remove unknown key id: $key_id");
}
unset($this->_keyPairs[$key_id]);
return $this;
}
/**
* Add a Certificate Pair to the list of certificates searched by the component
*
* @throws Zend_InfoCard_Exception
* @param string $private_key_file The path to the private key file for the pair
* @param string $public_key_file The path to the certificate / public key for the pair
* @param string $type (optional) The URI for the type of key pair this is (default RSA with OAEP padding)
* @param string $password (optional) The password for the private key file if necessary
* @return string A key ID representing this key pair in the component
*/
public function addCertificatePair($private_key_file, $public_key_file, $type = Zend_InfoCard_Cipher::ENC_RSA_OAEP_MGF1P, $password = null)
{
if(!file_exists($private_key_file) ||
!file_exists($public_key_file)) {
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Could not locate the public and private certificate pair files: $private_key_file, $public_key_file");
}
if(!is_readable($private_key_file) ||
!is_readable($public_key_file)) {
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Could not read the public and private certificate pair files (check permissions): $private_key_file, $public_key_file");
}
$key_id = md5($private_key_file.$public_key_file);
if(key_exists($key_id, $this->_keyPairs)) {
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Attempted to add previously existing certificate pair: $private_key_file, $public_key_file");
}
switch($type) {
case Zend_InfoCard_Cipher::ENC_RSA:
case Zend_InfoCard_Cipher::ENC_RSA_OAEP_MGF1P:
$this->_keyPairs[$key_id] = array('private' => $private_key_file,
'public' => $public_key_file,
'type_uri' => $type);
if($password !== null) {
$this->_keyPairs[$key_id]['password'] = $password;
} else {
$this->_keyPairs[$key_id]['password'] = null;
}
return $key_id;
break;
default:
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Invalid Certificate Pair Type specified: $type");
}
}
/**
* Return a Certificate Pair from a key ID
*
* @throws Zend_InfoCard_Exception
* @param string $key_id The Key ID of the certificate pair in the component
* @return array An array containing the path to the private/public key files,
* the type URI and the password if provided
*/
public function getCertificatePair($key_id)
{
if(key_exists($key_id, $this->_keyPairs)) {
return $this->_keyPairs[$key_id];
}
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Invalid Certificate Pair ID provided: $key_id");
}
/**
* Retrieve the digest of a given public key / certificate using the provided digest
* method
*
* @throws Zend_InfoCard_Exception
* @param string $key_id The certificate key id in the component
* @param string $digestMethod The URI of the digest method to use (default SHA1)
* @return string The digest value in binary format
*/
protected function _getPublicKeyDigest($key_id, $digestMethod = self::DIGEST_SHA1)
{
$certificatePair = $this->getCertificatePair($key_id);
$temp = file($certificatePair['public']);
unset($temp[count($temp)-1]);
unset($temp[0]);
$certificateData = base64_decode(implode("\n", $temp));
switch($digestMethod) {
case self::DIGEST_SHA1:
$digest_retval = sha1($certificateData, true);
break;
default:
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Invalid Digest Type Provided: $digestMethod");
}
return $digest_retval;
}
/**
* Find a certificate pair based on a digest of its public key / certificate file
*
* @param string $digest The digest value of the public key wanted in binary form
* @param string $digestMethod The URI of the digest method used to calculate the digest
* @return mixed The Key ID of the matching certificate pair or false if not found
*/
protected function _findCertifiatePairByDigest($digest, $digestMethod = self::DIGEST_SHA1)
{
foreach($this->_keyPairs as $key_id => $certificate_data) {
$cert_digest = $this->_getPublicKeyDigest($key_id, $digestMethod);
if($cert_digest == $digest) {
return $key_id;
}
}
return false;
}
/**
* Extracts the Signed Token from an EncryptedData block
*
* @throws Zend_InfoCard_Exception
* @param string $strXmlToken The EncryptedData XML block
* @return string The XML of the Signed Token inside of the EncryptedData block
*/
protected function _extractSignedToken($strXmlToken)
{
$encryptedData = Zend_InfoCard_Xml_EncryptedData::getInstance($strXmlToken);
// Determine the Encryption Method used to encrypt the token
switch($encryptedData->getEncryptionMethod()) {
case Zend_InfoCard_Cipher::ENC_AES128CBC:
case Zend_InfoCard_Cipher::ENC_AES256CBC:
break;
default:
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Unknown Encryption Method used in the secure token");
}
// Figure out the Key we are using to decrypt the token
$keyinfo = $encryptedData->getKeyInfo();
if(!($keyinfo instanceof Zend_InfoCard_Xml_KeyInfo_XmlDSig)) {
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Expected a XML digital signature KeyInfo, but was not found");
}
$encryptedKey = $keyinfo->getEncryptedKey();
switch($encryptedKey->getEncryptionMethod()) {
case Zend_InfoCard_Cipher::ENC_RSA:
case Zend_InfoCard_Cipher::ENC_RSA_OAEP_MGF1P:
break;
default:
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Unknown Key Encryption Method used in secure token");
}
$securityTokenRef = $encryptedKey->getKeyInfo()->getSecurityTokenReference();
$key_id = $this->_findCertifiatePairByDigest($securityTokenRef->getKeyReference());
if(!$key_id) {
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Unable to find key pair used to encrypt symmetric InfoCard Key");
}
$certificate_pair = $this->getCertificatePair($key_id);
// Santity Check
if($certificate_pair['type_uri'] != $encryptedKey->getEncryptionMethod()) {
require_once 'Zend/InfoCard/Exception.php';
throw new Zend_InfoCard_Exception("Certificate Pair which matches digest is not of same algorithm type as document, check addCertificate()");
}
$PKcipher = Zend_InfoCard_Cipher::getInstanceByURI($encryptedKey->getEncryptionMethod());
$base64DecodeSupportsStrictParam = version_compare(PHP_VERSION, '5.2.0', '>=');
if ($base64DecodeSupportsStrictParam) {
$keyCipherValueBase64Decoded = base64_decode($encryptedKey->getCipherValue(), true);
} else {
$keyCipherValueBase64Decoded = base64_decode($encryptedKey->getCipherValue());
}
$symmetricKey = $PKcipher->decrypt(
$keyCipherValueBase64Decoded,
file_get_contents($certificate_pair['private']),
$certificate_pair['password']
);
$symCipher = Zend_InfoCard_Cipher::getInstanceByURI($encryptedData->getEncryptionMethod());
if ($base64DecodeSupportsStrictParam) {
$dataCipherValueBase64Decoded = base64_decode($encryptedData->getCipherValue(), true);
} else {
$dataCipherValueBase64Decoded = base64_decode($encryptedData->getCipherValue());
}
$signedToken = $symCipher->decrypt($dataCipherValueBase64Decoded, $symmetricKey);
return $signedToken;
}
/**
* Process an input Infomation Card EncryptedData block sent from the client,
* validate it, and return the claims contained within it on success or an error message on error
*
* @param string $strXmlToken The XML token sent to the server from the client
* @return Zend_Infocard_Claims The Claims object containing the claims, or any errors which occurred
*/
public function process($strXmlToken)
{
$retval = new Zend_InfoCard_Claims();
require_once 'Zend/InfoCard/Exception.php';
try {
$signedAssertionsXml = $this->_extractSignedToken($strXmlToken);
} catch(Zend_InfoCard_Exception $e) {
$retval->setError('Failed to extract assertion document');
$retval->setCode(Zend_InfoCard_Claims::RESULT_PROCESSING_FAILURE);
return $retval;
}
try {
$assertions = Zend_InfoCard_Xml_Assertion::getInstance($signedAssertionsXml);
} catch(Zend_InfoCard_Exception $e) {
$retval->setError('Failure processing assertion document');
$retval->setCode(Zend_InfoCard_Claims::RESULT_PROCESSING_FAILURE);
return $retval;
}
if(!($assertions instanceof Zend_InfoCard_Xml_Assertion_Interface)) {
throw new Zend_InfoCard_Exception("Invalid Assertion Object returned");
}
if(!($reference_id = Zend_InfoCard_Xml_Security::validateXMLSignature($assertions->asXML()))) {
$retval->setError("Failure Validating the Signature of the assertion document");
$retval->setCode(Zend_InfoCard_Claims::RESULT_VALIDATION_FAILURE);
return $retval;
}
// The reference id should be locally scoped as far as I know
if($reference_id[0] == '#') {
$reference_id = substr($reference_id, 1);
} else {
$retval->setError("Reference of document signature does not reference the local document");
$retval->setCode(Zend_InfoCard_Claims::RESULT_VALIDATION_FAILURE);
return $retval;
}
// Make sure the signature is in reference to the same document as the assertions
if($reference_id != $assertions->getAssertionID()) {
$retval->setError("Reference of document signature does not reference the local document");
$retval->setCode(Zend_InfoCard_Claims::RESULT_VALIDATION_FAILURE);
}
// Validate we haven't seen this before and the conditions are acceptable
$conditions = $this->getAdapter()->retrieveAssertion($assertions->getAssertionURI(), $assertions->getAssertionID());
if($conditions === false) {
$conditions = $assertions->getConditions();
}
if(is_array($condition_error = $assertions->validateConditions($conditions))) {
$retval->setError("Conditions of assertion document are not met: {$condition_error[1]} ({$condition_error[0]})");
$retval->setCode(Zend_InfoCard_Claims::RESULT_VALIDATION_FAILURE);
}
$attributes = $assertions->getAttributes();
$retval->setClaims($attributes);
if($retval->getCode() == 0) {
$retval->setCode(Zend_InfoCard_Claims::RESULT_SUCCESS);
}
return $retval;
}
}