diff -r 5b37998e522e -r 162c1de6545a web/lib/Zend/InfoCard/Xml/Security.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/lib/Zend/InfoCard/Xml/Security.php	Fri Mar 11 15:05:35 2011 +0100
@@ -0,0 +1,327 @@
+<?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
+ * @subpackage Zend_InfoCard_Xml_Security
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ * @version    $Id: Security.php 23280 2010-10-31 10:28:58Z ramon $
+ */
+
+/**
+ * Zend_InfoCard_Xml_Security_Transform
+ */
+require_once 'Zend/InfoCard/Xml/Security/Transform.php';
+
+/**
+ *
+ * @category   Zend
+ * @package    Zend_InfoCard
+ * @subpackage Zend_InfoCard_Xml_Security
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ */
+class Zend_InfoCard_Xml_Security
+{
+    /**
+     * ASN.1 type INTEGER class
+     */
+    const ASN_TYPE_INTEGER = 0x02;
+
+    /**
+     * ASN.1 type BIT STRING class
+     */
+    const ASN_TYPE_BITSTRING = 0x03;
+
+    /**
+     * ASN.1 type SEQUENCE class
+     */
+    const ASN_TYPE_SEQUENCE = 0x30;
+
+    /**
+     * The URI for Canonical Method C14N Exclusive
+     */
+    const CANONICAL_METHOD_C14N_EXC = 'http://www.w3.org/2001/10/xml-exc-c14n#';
+
+    /**
+     * The URI for Signature Method SHA1
+     */
+    const SIGNATURE_METHOD_SHA1 = 'http://www.w3.org/2000/09/xmldsig#rsa-sha1';
+
+    /**
+     * The URI for Digest Method SHA1
+     */
+    const DIGEST_METHOD_SHA1 = 'http://www.w3.org/2000/09/xmldsig#sha1';
+
+    /**
+     * The Identifier for RSA Keys
+     */
+    const RSA_KEY_IDENTIFIER = '300D06092A864886F70D0101010500';
+
+    /**
+     * Constructor  (disabled)
+     *
+     * @return void
+     */
+    private function __construct()
+    {
+    }
+
+    /**
+     * Validates the signature of a provided XML block
+     *
+     * @param  string $strXMLInput An XML block containing a Signature
+     * @return bool True if the signature validated, false otherwise
+     * @throws Zend_InfoCard_Xml_Security_Exception
+     */
+    static public function validateXMLSignature($strXMLInput)
+    {
+        if(!extension_loaded('openssl')) {
+            require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+            throw new Zend_InfoCard_Xml_Security_Exception("You must have the openssl extension installed to use this class");
+        }
+
+        $sxe = simplexml_load_string($strXMLInput);
+
+        if(!isset($sxe->Signature)) {
+            require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+            throw new Zend_InfoCard_Xml_Security_Exception("Could not identify XML Signature element");
+        }
+
+        if(!isset($sxe->Signature->SignedInfo)) {
+            require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+            throw new Zend_InfoCard_Xml_Security_Exception("Signature is missing a SignedInfo block");
+        }
+
+        if(!isset($sxe->Signature->SignatureValue)) {
+            require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+            throw new Zend_InfoCard_Xml_Security_Exception("Signature is missing a SignatureValue block");
+        }
+
+        if(!isset($sxe->Signature->KeyInfo)) {
+            require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+            throw new Zend_InfoCard_Xml_Security_Exception("Signature is missing a KeyInfo block");
+        }
+
+        if(!isset($sxe->Signature->KeyInfo->KeyValue)) {
+            require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+            throw new Zend_InfoCard_Xml_Security_Exception("Signature is missing a KeyValue block");
+        }
+
+        switch((string)$sxe->Signature->SignedInfo->CanonicalizationMethod['Algorithm']) {
+            case self::CANONICAL_METHOD_C14N_EXC:
+                $cMethod = (string)$sxe->Signature->SignedInfo->CanonicalizationMethod['Algorithm'];
+                break;
+            default:
+                require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+                throw new Zend_InfoCard_Xml_Security_Exception("Unknown or unsupported CanonicalizationMethod Requested");
+                break;
+        }
+
+        switch((string)$sxe->Signature->SignedInfo->SignatureMethod['Algorithm']) {
+            case self::SIGNATURE_METHOD_SHA1:
+                $sMethod = (string)$sxe->Signature->SignedInfo->SignatureMethod['Algorithm'];
+                break;
+            default:
+                require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+                throw new Zend_InfoCard_Xml_Security_Exception("Unknown or unsupported SignatureMethod Requested");
+                break;
+        }
+
+        switch((string)$sxe->Signature->SignedInfo->Reference->DigestMethod['Algorithm']) {
+            case self::DIGEST_METHOD_SHA1:
+                $dMethod = (string)$sxe->Signature->SignedInfo->Reference->DigestMethod['Algorithm'];
+                break;
+            default:
+                require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+                throw new Zend_InfoCard_Xml_Security_Exception("Unknown or unsupported DigestMethod Requested");
+                break;
+        }
+
+        $base64DecodeSupportsStrictParam = version_compare(PHP_VERSION, '5.2.0', '>=');
+
+        if ($base64DecodeSupportsStrictParam) {
+            $dValue = base64_decode((string)$sxe->Signature->SignedInfo->Reference->DigestValue, true);
+        } else {
+            $dValue = base64_decode((string)$sxe->Signature->SignedInfo->Reference->DigestValue);
+        }
+
+        if ($base64DecodeSupportsStrictParam) {
+            $signatureValue = base64_decode((string)$sxe->Signature->SignatureValue, true);
+        } else {
+            $signatureValue = base64_decode((string)$sxe->Signature->SignatureValue);
+        }
+
+        $transformer = new Zend_InfoCard_Xml_Security_Transform();
+
+        foreach($sxe->Signature->SignedInfo->Reference->Transforms->children() as $transform) {
+            $transformer->addTransform((string)$transform['Algorithm']);
+        }
+
+        $transformed_xml = $transformer->applyTransforms($strXMLInput);
+
+        $transformed_xml_binhash = pack("H*", sha1($transformed_xml));
+
+        if(!self::_secureStringCompare($transformed_xml_binhash, $dValue)) {
+            require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+            throw new Zend_InfoCard_Xml_Security_Exception("Locally Transformed XML does not match XML Document. Cannot Verify Signature");
+        }
+
+        $public_key = null;
+
+        switch(true) {
+            case isset($sxe->Signature->KeyInfo->KeyValue->X509Certificate):
+
+                $certificate = (string)$sxe->Signature->KeyInfo->KeyValue->X509Certificate;
+
+
+                $pem = "-----BEGIN CERTIFICATE-----\n" .
+                       wordwrap($certificate, 64, "\n", true) .
+                       "\n-----END CERTIFICATE-----";
+
+                $public_key = openssl_pkey_get_public($pem);
+
+                if(!$public_key) {
+                    require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+                    throw new Zend_InfoCard_Xml_Security_Exception("Unable to extract and prcoess X509 Certificate from KeyValue");
+                }
+
+                break;
+            case isset($sxe->Signature->KeyInfo->KeyValue->RSAKeyValue):
+
+                if(!isset($sxe->Signature->KeyInfo->KeyValue->RSAKeyValue->Modulus) ||
+                   !isset($sxe->Signature->KeyInfo->KeyValue->RSAKeyValue->Exponent)) {
+                       require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+                       throw new Zend_InfoCard_Xml_Security_Exception("RSA Key Value not in Modulus/Exponent form");
+                }
+
+                $modulus = base64_decode((string)$sxe->Signature->KeyInfo->KeyValue->RSAKeyValue->Modulus);
+                $exponent = base64_decode((string)$sxe->Signature->KeyInfo->KeyValue->RSAKeyValue->Exponent);
+
+                $pem_public_key = self::_getPublicKeyFromModExp($modulus, $exponent);
+
+                $public_key = openssl_pkey_get_public ($pem_public_key);
+
+                break;
+            default:
+                require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+                throw new Zend_InfoCard_Xml_Security_Exception("Unable to determine or unsupported representation of the KeyValue block");
+        }
+
+        $transformer = new Zend_InfoCard_Xml_Security_Transform();
+        $transformer->addTransform((string)$sxe->Signature->SignedInfo->CanonicalizationMethod['Algorithm']);
+
+        // The way we are doing our XML processing requires that we specifically add this
+        // (even though it's in the <Signature> parent-block).. otherwise, our canonical form
+        // fails signature verification
+        $sxe->Signature->SignedInfo->addAttribute('xmlns', 'http://www.w3.org/2000/09/xmldsig#');
+
+        $canonical_signedinfo = $transformer->applyTransforms($sxe->Signature->SignedInfo->asXML());
+
+        if(@openssl_verify($canonical_signedinfo, $signatureValue, $public_key)) {
+            return (string)$sxe->Signature->SignedInfo->Reference['URI'];
+        }
+
+        return false;
+    }
+
+    /**
+     * Transform an RSA Key in Modulus/Exponent format into a PEM encoding and
+     * return an openssl resource for it
+     *
+     * @param string $modulus The RSA Modulus in binary format
+     * @param string $exponent The RSA exponent in binary format
+     * @return string The PEM encoded version of the key
+     */
+    static protected function _getPublicKeyFromModExp($modulus, $exponent)
+    {
+        $modulusInteger  = self::_encodeValue($modulus, self::ASN_TYPE_INTEGER);
+        $exponentInteger = self::_encodeValue($exponent, self::ASN_TYPE_INTEGER);
+        $modExpSequence  = self::_encodeValue($modulusInteger . $exponentInteger, self::ASN_TYPE_SEQUENCE);
+        $modExpBitString = self::_encodeValue($modExpSequence, self::ASN_TYPE_BITSTRING);
+
+        $binRsaKeyIdentifier = pack( "H*", self::RSA_KEY_IDENTIFIER );
+
+        $publicKeySequence = self::_encodeValue($binRsaKeyIdentifier . $modExpBitString, self::ASN_TYPE_SEQUENCE);
+
+        $publicKeyInfoBase64 = base64_encode( $publicKeySequence );
+
+        $publicKeyString = "-----BEGIN PUBLIC KEY-----\n";
+        $publicKeyString .= wordwrap($publicKeyInfoBase64, 64, "\n", true);
+        $publicKeyString .= "\n-----END PUBLIC KEY-----\n";
+
+        return $publicKeyString;
+    }
+
+    /**
+     * Encode a limited set of data types into ASN.1 encoding format
+     * which is used in X.509 certificates
+     *
+     * @param string $data The data to encode
+     * @param const $type The encoding format constant
+     * @return string The encoded value
+     * @throws Zend_InfoCard_Xml_Security_Exception
+     */
+    static protected function _encodeValue($data, $type)
+    {
+        // Null pad some data when we get it (integer values > 128 and bitstrings)
+        if( (($type == self::ASN_TYPE_INTEGER) && (ord($data) > 0x7f)) ||
+            ($type == self::ASN_TYPE_BITSTRING)) {
+                $data = "\0$data";
+        }
+
+        $len = strlen($data);
+
+        // encode the value based on length of the string
+        // I'm fairly confident that this is by no means a complete implementation
+        // but it is enough for our purposes
+        switch(true) {
+            case ($len < 128):
+                return sprintf("%c%c%s", $type, $len, $data);
+            case ($len < 0x0100):
+                return sprintf("%c%c%c%s", $type, 0x81, $len, $data);
+            case ($len < 0x010000):
+                return sprintf("%c%c%c%c%s", $type, 0x82, $len / 0x0100, $len % 0x0100, $data);
+            default:
+                require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+                throw new Zend_InfoCard_Xml_Security_Exception("Could not encode value");
+        }
+
+        require_once 'Zend/InfoCard/Xml/Security/Exception.php';
+        throw new Zend_InfoCard_Xml_Security_Exception("Invalid code path");
+    }
+
+    /**
+     * Securely compare two strings for equality while avoided C level memcmp()
+     * optimisations capable of leaking timing information useful to an attacker
+     * attempting to iteratively guess the unknown string (e.g. password) being
+     * compared against.
+     *
+     * @param string $a
+     * @param string $b
+     * @return bool
+     */
+    static protected function _secureStringCompare($a, $b)
+    {
+        if (strlen($a) !== strlen($b)) {
+            return false;
+        }
+        $result = 0;
+        for ($i = 0; $i < strlen($a); $i++) {
+            $result |= ord($a[$i]) ^ ord($b[$i]);
+        }
+        return $result == 0;
+    }
+}