friendica-addons/saml/vendor/onelogin/php-saml/src/Saml2/Response.php

1238 lines
46 KiB
PHP

<?php
/**
* This file is part of php-saml.
*
* (c) OneLogin Inc
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*
* @package OneLogin
* @author OneLogin Inc <saml-info@onelogin.com>
* @license MIT https://github.com/onelogin/php-saml/blob/master/LICENSE
* @link https://github.com/onelogin/php-saml
*/
namespace OneLogin\Saml2;
use RobRichards\XMLSecLibs\XMLSecurityKey;
use RobRichards\XMLSecLibs\XMLSecEnc;
use DOMDocument;
use DOMNodeList;
use DOMXPath;
use Exception;
/**
* SAML 2 Authentication Response
*/
class Response
{
/**
* Settings
*
* @var Settings
*/
protected $_settings;
/**
* The decoded, unprocessed XML response provided to the constructor.
*
* @var string
*/
public $response;
/**
* A DOMDocument class loaded from the SAML Response.
*
* @var DOMDocument
*/
public $document;
/**
* A DOMDocument class loaded from the SAML Response (Decrypted).
*
* @var DOMDocument
*/
public $decryptedDocument;
/**
* The response contains an encrypted assertion.
*
* @var bool
*/
public $encrypted = false;
/**
* After validation, if it fail this var has the cause of the problem
*
* @var Exception|null
*/
private $_error;
/**
* NotOnOrAfter value of a valid SubjectConfirmationData node
*
* @var int
*/
private $_validSCDNotOnOrAfter;
/**
* Constructs the SAML Response object.
*
* @param Settings $settings Settings.
* @param string $response A UUEncoded SAML response from the IdP.
*
* @throws Exception
* @throws ValidationError
*/
public function __construct(\OneLogin\Saml2\Settings $settings, $response)
{
$this->_settings = $settings;
$baseURL = $this->_settings->getBaseURL();
if (!empty($baseURL)) {
Utils::setBaseURL($baseURL);
}
$this->response = base64_decode($response);
$this->document = new DOMDocument();
$this->document = Utils::loadXML($this->document, $this->response);
if (!$this->document) {
throw new ValidationError(
"SAML Response could not be processed",
ValidationError::INVALID_XML_FORMAT
);
}
// Quick check for the presence of EncryptedAssertion
$encryptedAssertionNodes = $this->document->getElementsByTagName('EncryptedAssertion');
if ($encryptedAssertionNodes->length !== 0) {
$this->decryptedDocument = clone $this->document;
$this->encrypted = true;
$this->decryptedDocument = $this->decryptAssertion($this->decryptedDocument);
}
}
/**
* Determines if the SAML Response is valid using the certificate.
*
* @param string|null $requestId The ID of the AuthNRequest sent by this SP to the IdP
*
* @return bool Validate the document
*
* @throws Exception
* @throws ValidationError
*/
public function isValid($requestId = null)
{
$this->_error = null;
try {
// Check SAML version
if ($this->document->documentElement->getAttribute('Version') != '2.0') {
throw new ValidationError(
"Unsupported SAML version",
ValidationError::UNSUPPORTED_SAML_VERSION
);
}
if (!$this->document->documentElement->hasAttribute('ID')) {
throw new ValidationError(
"Missing ID attribute on SAML Response",
ValidationError::MISSING_ID
);
}
$this->checkStatus();
$singleAssertion = $this->validateNumAssertions();
if (!$singleAssertion) {
throw new ValidationError(
"SAML Response must contain 1 assertion",
ValidationError::WRONG_NUMBER_OF_ASSERTIONS
);
}
$idpData = $this->_settings->getIdPData();
$idPEntityId = $idpData['entityId'];
$spData = $this->_settings->getSPData();
$spEntityId = $spData['entityId'];
$signedElements = $this->processSignedElements();
$responseTag = '{'.Constants::NS_SAMLP.'}Response';
$assertionTag = '{'.Constants::NS_SAML.'}Assertion';
$hasSignedResponse = in_array($responseTag, $signedElements);
$hasSignedAssertion = in_array($assertionTag, $signedElements);
if ($this->_settings->isStrict()) {
$security = $this->_settings->getSecurityData();
if ($security['wantXMLValidation']) {
$errorXmlMsg = "Invalid SAML Response. Not match the saml-schema-protocol-2.0.xsd";
$res = Utils::validateXML($this->document, 'saml-schema-protocol-2.0.xsd', $this->_settings->isDebugActive(), $this->_settings->getSchemasPath());
if (!$res instanceof DOMDocument) {
throw new ValidationError(
$errorXmlMsg,
ValidationError::INVALID_XML_FORMAT
);
}
// If encrypted, check also the decrypted document
if ($this->encrypted) {
$res = Utils::validateXML($this->decryptedDocument, 'saml-schema-protocol-2.0.xsd', $this->_settings->isDebugActive(), $this->_settings->getSchemasPath());
if (!$res instanceof DOMDocument) {
throw new ValidationError(
$errorXmlMsg,
ValidationError::INVALID_XML_FORMAT
);
}
}
}
$currentURL = Utils::getSelfRoutedURLNoQuery();
$responseInResponseTo = null;
if ($this->document->documentElement->hasAttribute('InResponseTo')) {
$responseInResponseTo = $this->document->documentElement->getAttribute('InResponseTo');
}
if (!isset($requestId) && isset($responseInResponseTo) && $security['rejectUnsolicitedResponsesWithInResponseTo']) {
throw new ValidationError(
"The Response has an InResponseTo attribute: " . $responseInResponseTo . " while no InResponseTo was expected",
ValidationError::WRONG_INRESPONSETO
);
}
// Check if the InResponseTo of the Response matchs the ID of the AuthNRequest (requestId) if provided
if (isset($requestId) && $requestId != $responseInResponseTo) {
if ($responseInResponseTo == null) {
throw new ValidationError(
"No InResponseTo at the Response, but it was provided the requestId related to the AuthNRequest sent by the SP: $requestId",
ValidationError::WRONG_INRESPONSETO
);
} else {
throw new ValidationError(
"The InResponseTo of the Response: $responseInResponseTo, does not match the ID of the AuthNRequest sent by the SP: $requestId",
ValidationError::WRONG_INRESPONSETO
);
}
}
if (!$this->encrypted && $security['wantAssertionsEncrypted']) {
throw new ValidationError(
"The assertion of the Response is not encrypted and the SP requires it",
ValidationError::NO_ENCRYPTED_ASSERTION
);
}
if ($security['wantNameIdEncrypted']) {
$encryptedIdNodes = $this->_queryAssertion('/saml:Subject/saml:EncryptedID/xenc:EncryptedData');
if ($encryptedIdNodes->length != 1) {
throw new ValidationError(
"The NameID of the Response is not encrypted and the SP requires it",
ValidationError::NO_ENCRYPTED_NAMEID
);
}
}
// Validate Conditions element exists
if (!$this->checkOneCondition()) {
throw new ValidationError(
"The Assertion must include a Conditions element",
ValidationError::MISSING_CONDITIONS
);
}
// Validate Asserion timestamps
$this->validateTimestamps();
// Validate AuthnStatement element exists and is unique
if (!$this->checkOneAuthnStatement()) {
throw new ValidationError(
"The Assertion must include an AuthnStatement element",
ValidationError::WRONG_NUMBER_OF_AUTHSTATEMENTS
);
}
// EncryptedAttributes are not supported
$encryptedAttributeNodes = $this->_queryAssertion('/saml:AttributeStatement/saml:EncryptedAttribute');
if ($encryptedAttributeNodes->length > 0) {
throw new ValidationError(
"There is an EncryptedAttribute in the Response and this SP not support them",
ValidationError::ENCRYPTED_ATTRIBUTES
);
}
// Check destination
if ($this->document->documentElement->hasAttribute('Destination')) {
$destination = trim($this->document->documentElement->getAttribute('Destination'));
if (empty($destination)) {
if (!$security['relaxDestinationValidation']) {
throw new ValidationError(
"The response has an empty Destination value",
ValidationError::EMPTY_DESTINATION
);
}
} else {
$urlComparisonLength = $security['destinationStrictlyMatches'] ? strlen($destination) : strlen($currentURL);
if (strncmp($destination, $currentURL, $urlComparisonLength) !== 0) {
$currentURLNoRouted = Utils::getSelfURLNoQuery();
$urlComparisonLength = $security['destinationStrictlyMatches'] ? strlen($destination) : strlen($currentURLNoRouted);
if (strncmp($destination, $currentURLNoRouted, $urlComparisonLength) !== 0) {
throw new ValidationError(
"The response was received at $currentURL instead of $destination",
ValidationError::WRONG_DESTINATION
);
}
}
}
}
// Check audience
$validAudiences = $this->getAudiences();
if (!empty($validAudiences) && !in_array($spEntityId, $validAudiences, true)) {
throw new ValidationError(
sprintf(
"Invalid audience for this Response (expected '%s', got '%s')",
$spEntityId,
implode(',', $validAudiences)
),
ValidationError::WRONG_AUDIENCE
);
}
// Check the issuers
$issuers = $this->getIssuers();
foreach ($issuers as $issuer) {
$trimmedIssuer = trim($issuer);
if (empty($trimmedIssuer) || $trimmedIssuer !== $idPEntityId) {
throw new ValidationError(
"Invalid issuer in the Assertion/Response (expected '$idPEntityId', got '$trimmedIssuer')",
ValidationError::WRONG_ISSUER
);
}
}
// Check the session Expiration
$sessionExpiration = $this->getSessionNotOnOrAfter();
if (!empty($sessionExpiration) && $sessionExpiration + Constants::ALLOWED_CLOCK_DRIFT <= time()) {
throw new ValidationError(
"The attributes have expired, based on the SessionNotOnOrAfter of the AttributeStatement of this Response",
ValidationError::SESSION_EXPIRED
);
}
// Check the SubjectConfirmation, at least one SubjectConfirmation must be valid
$anySubjectConfirmation = false;
$subjectConfirmationNodes = $this->_queryAssertion('/saml:Subject/saml:SubjectConfirmation');
foreach ($subjectConfirmationNodes as $scn) {
if ($scn->hasAttribute('Method') && $scn->getAttribute('Method') != Constants::CM_BEARER) {
continue;
}
$subjectConfirmationDataNodes = $scn->getElementsByTagName('SubjectConfirmationData');
if ($subjectConfirmationDataNodes->length == 0) {
continue;
} else {
$scnData = $subjectConfirmationDataNodes->item(0);
if ($scnData->hasAttribute('InResponseTo')) {
$inResponseTo = $scnData->getAttribute('InResponseTo');
if (isset($responseInResponseTo) && $responseInResponseTo != $inResponseTo) {
continue;
}
}
if ($scnData->hasAttribute('Recipient')) {
$recipient = $scnData->getAttribute('Recipient');
if (!empty($recipient) && strpos($recipient, $currentURL) === false) {
continue;
}
}
if ($scnData->hasAttribute('NotOnOrAfter')) {
$noa = Utils::parseSAML2Time($scnData->getAttribute('NotOnOrAfter'));
if ($noa + Constants::ALLOWED_CLOCK_DRIFT <= time()) {
continue;
}
}
if ($scnData->hasAttribute('NotBefore')) {
$nb = Utils::parseSAML2Time($scnData->getAttribute('NotBefore'));
if ($nb > time() + Constants::ALLOWED_CLOCK_DRIFT) {
continue;
}
}
// Save NotOnOrAfter value
if ($scnData->hasAttribute('NotOnOrAfter')) {
$this->_validSCDNotOnOrAfter = $noa;
}
$anySubjectConfirmation = true;
break;
}
}
if (!$anySubjectConfirmation) {
throw new ValidationError(
"A valid SubjectConfirmation was not found on this Response",
ValidationError::WRONG_SUBJECTCONFIRMATION
);
}
if ($security['wantAssertionsSigned'] && !$hasSignedAssertion) {
throw new ValidationError(
"The Assertion of the Response is not signed and the SP requires it",
ValidationError::NO_SIGNED_ASSERTION
);
}
if ($security['wantMessagesSigned'] && !$hasSignedResponse) {
throw new ValidationError(
"The Message of the Response is not signed and the SP requires it",
ValidationError::NO_SIGNED_MESSAGE
);
}
}
// Detect case not supported
if ($this->encrypted) {
$encryptedIDNodes = Utils::query($this->decryptedDocument, '/samlp:Response/saml:Assertion/saml:Subject/saml:EncryptedID');
if ($encryptedIDNodes->length > 0) {
throw new ValidationError(
'SAML Response that contains an encrypted Assertion with encrypted nameId is not supported.',
ValidationError::NOT_SUPPORTED
);
}
}
if (empty($signedElements) || (!$hasSignedResponse && !$hasSignedAssertion)) {
throw new ValidationError(
'No Signature found. SAML Response rejected',
ValidationError::NO_SIGNATURE_FOUND
);
} else {
$cert = $idpData['x509cert'];
$fingerprint = $idpData['certFingerprint'];
$fingerprintalg = $idpData['certFingerprintAlgorithm'];
$multiCerts = null;
$existsMultiX509Sign = isset($idpData['x509certMulti']) && isset($idpData['x509certMulti']['signing']) && !empty($idpData['x509certMulti']['signing']);
if ($existsMultiX509Sign) {
$multiCerts = $idpData['x509certMulti']['signing'];
}
// If find a Signature on the Response, validates it checking the original response
if ($hasSignedResponse && !Utils::validateSign($this->document, $cert, $fingerprint, $fingerprintalg, Utils::RESPONSE_SIGNATURE_XPATH, $multiCerts)) {
throw new ValidationError(
"Signature validation failed. SAML Response rejected",
ValidationError::INVALID_SIGNATURE
);
}
// If find a Signature on the Assertion (decrypted assertion if was encrypted)
$documentToCheckAssertion = $this->encrypted ? $this->decryptedDocument : $this->document;
if ($hasSignedAssertion && !Utils::validateSign($documentToCheckAssertion, $cert, $fingerprint, $fingerprintalg, Utils::ASSERTION_SIGNATURE_XPATH, $multiCerts)) {
throw new ValidationError(
"Signature validation failed. SAML Response rejected",
ValidationError::INVALID_SIGNATURE
);
}
}
return true;
} catch (Exception $e) {
$this->_error = $e;
$debug = $this->_settings->isDebugActive();
if ($debug) {
echo htmlentities($e->getMessage());
}
return false;
}
}
/**
* @return string|null the ID of the Response
*/
public function getId()
{
$id = null;
if ($this->document->documentElement->hasAttribute('ID')) {
$id = $this->document->documentElement->getAttribute('ID');
}
return $id;
}
/**
* @return string|null the ID of the assertion in the Response
*
* @throws ValidationError
*/
public function getAssertionId()
{
if (!$this->validateNumAssertions()) {
throw new ValidationError("SAML Response must contain 1 Assertion.", ValidationError::WRONG_NUMBER_OF_ASSERTIONS);
}
$assertionNodes = $this->_queryAssertion("");
$id = null;
if ($assertionNodes->length == 1 && $assertionNodes->item(0)->hasAttribute('ID')) {
$id = $assertionNodes->item(0)->getAttribute('ID');
}
return $id;
}
/**
* @return int the NotOnOrAfter value of the valid SubjectConfirmationData
* node if any
*/
public function getAssertionNotOnOrAfter()
{
return $this->_validSCDNotOnOrAfter;
}
/**
* Checks if the Status is success
*
* @throws ValidationError If status is not success
*/
public function checkStatus()
{
$status = Utils::getStatus($this->document);
if (isset($status['code']) && $status['code'] !== Constants::STATUS_SUCCESS) {
$explodedCode = explode(':', $status['code']);
$printableCode = array_pop($explodedCode);
$statusExceptionMsg = 'The status code of the Response was not Success, was '.$printableCode;
if (!empty($status['msg'])) {
$statusExceptionMsg .= ' -> '.$status['msg'];
}
throw new ValidationError(
$statusExceptionMsg,
ValidationError::STATUS_CODE_IS_NOT_SUCCESS
);
}
}
/**
* Checks that the samlp:Response/saml:Assertion/saml:Conditions element exists and is unique.
*
* @return boolean true if the Conditions element exists and is unique
*/
public function checkOneCondition()
{
$entries = $this->_queryAssertion("/saml:Conditions");
if ($entries->length == 1) {
return true;
} else {
return false;
}
}
/**
* Checks that the samlp:Response/saml:Assertion/saml:AuthnStatement element exists and is unique.
*
* @return boolean true if the AuthnStatement element exists and is unique
*/
public function checkOneAuthnStatement()
{
$entries = $this->_queryAssertion("/saml:AuthnStatement");
if ($entries->length == 1) {
return true;
} else {
return false;
}
}
/**
* Gets the audiences.
*
* @return array @audience The valid audiences of the response
*/
public function getAudiences()
{
$audiences = array();
$entries = $this->_queryAssertion('/saml:Conditions/saml:AudienceRestriction/saml:Audience');
foreach ($entries as $entry) {
$value = trim($entry->textContent);
if (!empty($value)) {
$audiences[] = $value;
}
}
return array_unique($audiences);
}
/**
* Gets the Issuers (from Response and Assertion).
*
* @return array @issuers The issuers of the assertion/response
*
* @throws ValidationError
*/
public function getIssuers()
{
$issuers = array();
$responseIssuer = Utils::query($this->document, '/samlp:Response/saml:Issuer');
if ($responseIssuer->length > 0) {
if ($responseIssuer->length == 1) {
$issuers[] = $responseIssuer->item(0)->textContent;
} else {
throw new ValidationError(
"Issuer of the Response is multiple.",
ValidationError::ISSUER_MULTIPLE_IN_RESPONSE
);
}
}
$assertionIssuer = $this->_queryAssertion('/saml:Issuer');
if ($assertionIssuer->length == 1) {
$issuers[] = $assertionIssuer->item(0)->textContent;
} else {
throw new ValidationError(
"Issuer of the Assertion not found or multiple.",
ValidationError::ISSUER_NOT_FOUND_IN_ASSERTION
);
}
return array_unique($issuers);
}
/**
* Gets the NameID Data provided by the SAML response from the IdP.
*
* @return array Name ID Data (Value, Format, NameQualifier, SPNameQualifier)
*
* @throws ValidationError
*/
public function getNameIdData()
{
$encryptedIdDataEntries = $this->_queryAssertion('/saml:Subject/saml:EncryptedID/xenc:EncryptedData');
if ($encryptedIdDataEntries->length == 1) {
$encryptedData = $encryptedIdDataEntries->item(0);
$key = $this->_settings->getSPkey();
$seckey = new XMLSecurityKey(XMLSecurityKey::RSA_1_5, array('type'=>'private'));
$seckey->loadKey($key);
$nameId = Utils::decryptElement($encryptedData, $seckey);
} else {
$entries = $this->_queryAssertion('/saml:Subject/saml:NameID');
if ($entries->length == 1) {
$nameId = $entries->item(0);
}
}
$nameIdData = array();
if (!isset($nameId)) {
$security = $this->_settings->getSecurityData();
if ($security['wantNameId']) {
throw new ValidationError(
"NameID not found in the assertion of the Response",
ValidationError::NO_NAMEID
);
}
} else {
if ($this->_settings->isStrict() && empty($nameId->nodeValue)) {
throw new ValidationError(
"An empty NameID value found",
ValidationError::EMPTY_NAMEID
);
}
$nameIdData['Value'] = $nameId->nodeValue;
foreach (array('Format', 'SPNameQualifier', 'NameQualifier') as $attr) {
if ($nameId->hasAttribute($attr)) {
if ($this->_settings->isStrict() && $attr == 'SPNameQualifier') {
$spData = $this->_settings->getSPData();
$spEntityId = $spData['entityId'];
if ($spEntityId != $nameId->getAttribute($attr)) {
throw new ValidationError(
"The SPNameQualifier value mistmatch the SP entityID value.",
ValidationError::SP_NAME_QUALIFIER_NAME_MISMATCH
);
}
}
$nameIdData[$attr] = $nameId->getAttribute($attr);
}
}
}
return $nameIdData;
}
/**
* Gets the NameID provided by the SAML response from the IdP.
*
* @return string|null Name ID Value
*
* @throws ValidationError
*/
public function getNameId()
{
$nameIdvalue = null;
$nameIdData = $this->getNameIdData();
if (!empty($nameIdData) && isset($nameIdData['Value'])) {
$nameIdvalue = $nameIdData['Value'];
}
return $nameIdvalue;
}
/**
* Gets the NameID Format provided by the SAML response from the IdP.
*
* @return string|null Name ID Format
*
* @throws ValidationError
*/
public function getNameIdFormat()
{
$nameIdFormat = null;
$nameIdData = $this->getNameIdData();
if (!empty($nameIdData) && isset($nameIdData['Format'])) {
$nameIdFormat = $nameIdData['Format'];
}
return $nameIdFormat;
}
/**
* Gets the NameID NameQualifier provided by the SAML response from the IdP.
*
* @return string|null Name ID NameQualifier
*
* @throws ValidationError
*/
public function getNameIdNameQualifier()
{
$nameIdNameQualifier = null;
$nameIdData = $this->getNameIdData();
if (!empty($nameIdData) && isset($nameIdData['NameQualifier'])) {
$nameIdNameQualifier = $nameIdData['NameQualifier'];
}
return $nameIdNameQualifier;
}
/**
* Gets the NameID SP NameQualifier provided by the SAML response from the IdP.
*
* @return string|null NameID SP NameQualifier
*
* @throws ValidationError
*/
public function getNameIdSPNameQualifier()
{
$nameIdSPNameQualifier = null;
$nameIdData = $this->getNameIdData();
if (!empty($nameIdData) && isset($nameIdData['SPNameQualifier'])) {
$nameIdSPNameQualifier = $nameIdData['SPNameQualifier'];
}
return $nameIdSPNameQualifier;
}
/**
* Gets the SessionNotOnOrAfter from the AuthnStatement.
* Could be used to set the local session expiration
*
* @return int|null The SessionNotOnOrAfter value
*
* @throws Exception
*/
public function getSessionNotOnOrAfter()
{
$notOnOrAfter = null;
$entries = $this->_queryAssertion('/saml:AuthnStatement[@SessionNotOnOrAfter]');
if ($entries->length !== 0) {
$notOnOrAfter = Utils::parseSAML2Time($entries->item(0)->getAttribute('SessionNotOnOrAfter'));
}
return $notOnOrAfter;
}
/**
* Gets the SessionIndex from the AuthnStatement.
* Could be used to be stored in the local session in order
* to be used in a future Logout Request that the SP could
* send to the SP, to set what specific session must be deleted
*
* @return string|null The SessionIndex value
*/
public function getSessionIndex()
{
$sessionIndex = null;
$entries = $this->_queryAssertion('/saml:AuthnStatement[@SessionIndex]');
if ($entries->length !== 0) {
$sessionIndex = $entries->item(0)->getAttribute('SessionIndex');
}
return $sessionIndex;
}
/**
* Gets the Attributes from the AttributeStatement element.
*
* @return array The attributes of the SAML Assertion
*
* @throws ValidationError
*/
public function getAttributes()
{
return $this->_getAttributesByKeyName('Name');
}
/**
* Gets the Attributes from the AttributeStatement element using their FriendlyName.
*
* @return array The attributes of the SAML Assertion
*
* @throws ValidationError
*/
public function getAttributesWithFriendlyName()
{
return $this->_getAttributesByKeyName('FriendlyName');
}
/**
* @param string $keyName
*
* @return array
*
* @throws ValidationError
*/
private function _getAttributesByKeyName($keyName = "Name")
{
$attributes = array();
$entries = $this->_queryAssertion('/saml:AttributeStatement/saml:Attribute');
$security = $this->_settings->getSecurityData();
$allowRepeatAttributeName = $security['allowRepeatAttributeName'];
/** @var $entry DOMNode */
foreach ($entries as $entry) {
$attributeKeyNode = $entry->attributes->getNamedItem($keyName);
if ($attributeKeyNode === null) {
continue;
}
$attributeKeyName = $attributeKeyNode->nodeValue;
if (in_array($attributeKeyName, array_keys($attributes))) {
if (!$allowRepeatAttributeName) {
throw new ValidationError(
"Found an Attribute element with duplicated ".$keyName,
ValidationError::DUPLICATED_ATTRIBUTE_NAME_FOUND
);
}
}
$attributeValues = array();
foreach ($entry->childNodes as $childNode) {
$tagName = ($childNode->prefix ? $childNode->prefix.':' : '') . 'AttributeValue';
if ($childNode->nodeType == XML_ELEMENT_NODE && $childNode->tagName === $tagName) {
$attributeValues[] = $childNode->nodeValue;
}
}
if (in_array($attributeKeyName, array_keys($attributes))) {
$attributes[$attributeKeyName] = array_merge($attributes[$attributeKeyName], $attributeValues);
} else {
$attributes[$attributeKeyName] = $attributeValues;
}
}
return $attributes;
}
/**
* Verifies that the document only contains a single Assertion (encrypted or not).
*
* @return bool TRUE if the document passes.
*/
public function validateNumAssertions()
{
$encryptedAssertionNodes = $this->document->getElementsByTagName('EncryptedAssertion');
$assertionNodes = $this->document->getElementsByTagName('Assertion');
$valid = $assertionNodes->length + $encryptedAssertionNodes->length == 1;
if ($this->encrypted) {
$assertionNodes = $this->decryptedDocument->getElementsByTagName('Assertion');
$valid = $valid && $assertionNodes->length == 1;
}
return $valid;
}
/**
* Verifies the signature nodes:
* - Checks that are Response or Assertion
* - Check that IDs and reference URI are unique and consistent.
*
* @return array Signed element tags
*
* @throws ValidationError
*/
public function processSignedElements()
{
$signedElements = array();
$verifiedSeis = array();
$verifiedIds = array();
if ($this->encrypted) {
$signNodes = $this->decryptedDocument->getElementsByTagName('Signature');
} else {
$signNodes = $this->document->getElementsByTagName('Signature');
}
foreach ($signNodes as $signNode) {
$responseTag = '{'.Constants::NS_SAMLP.'}Response';
$assertionTag = '{'.Constants::NS_SAML.'}Assertion';
$signedElement = '{'.$signNode->parentNode->namespaceURI.'}'.$signNode->parentNode->localName;
if ($signedElement != $responseTag && $signedElement != $assertionTag) {
throw new ValidationError(
"Invalid Signature Element $signedElement SAML Response rejected",
ValidationError::WRONG_SIGNED_ELEMENT
);
}
// Check that reference URI matches the parent ID and no duplicate References or IDs
$idValue = $signNode->parentNode->getAttribute('ID');
if (empty($idValue)) {
throw new ValidationError(
'Signed Element must contain an ID. SAML Response rejected',
ValidationError::ID_NOT_FOUND_IN_SIGNED_ELEMENT
);
}
if (in_array($idValue, $verifiedIds)) {
throw new ValidationError(
'Duplicated ID. SAML Response rejected',
ValidationError::DUPLICATED_ID_IN_SIGNED_ELEMENTS
);
}
$verifiedIds[] = $idValue;
$ref = $signNode->getElementsByTagName('Reference');
if ($ref->length == 1) {
$ref = $ref->item(0);
$sei = $ref->getAttribute('URI');
if (!empty($sei)) {
$sei = substr($sei, 1);
if ($sei != $idValue) {
throw new ValidationError(
'Found an invalid Signed Element. SAML Response rejected',
ValidationError::INVALID_SIGNED_ELEMENT
);
}
if (in_array($sei, $verifiedSeis)) {
throw new ValidationError(
'Duplicated Reference URI. SAML Response rejected',
ValidationError::DUPLICATED_REFERENCE_IN_SIGNED_ELEMENTS
);
}
$verifiedSeis[] = $sei;
}
} else {
throw new ValidationError(
'Unexpected number of Reference nodes found for signature. SAML Response rejected.',
ValidationError::UNEXPECTED_REFERENCE
);
}
$signedElements[] = $signedElement;
}
// Check SignedElements
if (!empty($signedElements) && !$this->validateSignedElements($signedElements)) {
throw new ValidationError(
'Found an unexpected Signature Element. SAML Response rejected',
ValidationError::UNEXPECTED_SIGNED_ELEMENTS
);
}
return $signedElements;
}
/**
* Verifies that the document is still valid according Conditions Element.
*
* @return bool
*
* @throws Exception
* @throws ValidationError
*/
public function validateTimestamps()
{
if ($this->encrypted) {
$document = $this->decryptedDocument;
} else {
$document = $this->document;
}
$timestampNodes = $document->getElementsByTagName('Conditions');
for ($i = 0; $i < $timestampNodes->length; $i++) {
$nbAttribute = $timestampNodes->item($i)->attributes->getNamedItem("NotBefore");
$naAttribute = $timestampNodes->item($i)->attributes->getNamedItem("NotOnOrAfter");
if ($nbAttribute && Utils::parseSAML2Time($nbAttribute->textContent) > time() + Constants::ALLOWED_CLOCK_DRIFT) {
throw new ValidationError(
'Could not validate timestamp: not yet valid. Check system clock.',
ValidationError::ASSERTION_TOO_EARLY
);
}
if ($naAttribute && Utils::parseSAML2Time($naAttribute->textContent) + Constants::ALLOWED_CLOCK_DRIFT <= time()) {
throw new ValidationError(
'Could not validate timestamp: expired. Check system clock.',
ValidationError::ASSERTION_EXPIRED
);
}
}
return true;
}
/**
* Verifies that the document has the expected signed nodes.
*
* @param array $signedElements Signed elements
*
* @return bool
*
* @throws ValidationError
*/
public function validateSignedElements($signedElements)
{
if (count($signedElements) > 2) {
return false;
}
$responseTag = '{'.Constants::NS_SAMLP.'}Response';
$assertionTag = '{'.Constants::NS_SAML.'}Assertion';
$ocurrence = array_count_values($signedElements);
if ((in_array($responseTag, $signedElements) && $ocurrence[$responseTag] > 1)
|| (in_array($assertionTag, $signedElements) && $ocurrence[$assertionTag] > 1)
|| !in_array($responseTag, $signedElements) && !in_array($assertionTag, $signedElements)
) {
return false;
}
// Check that the signed elements found here, are the ones that will be verified
// by Utils->validateSign()
if (in_array($responseTag, $signedElements)) {
$expectedSignatureNodes = Utils::query($this->document, Utils::RESPONSE_SIGNATURE_XPATH);
if ($expectedSignatureNodes->length != 1) {
throw new ValidationError(
"Unexpected number of Response signatures found. SAML Response rejected.",
ValidationError::WRONG_NUMBER_OF_SIGNATURES_IN_RESPONSE
);
}
}
if (in_array($assertionTag, $signedElements)) {
$expectedSignatureNodes = $this->_query(Utils::ASSERTION_SIGNATURE_XPATH);
if ($expectedSignatureNodes->length != 1) {
throw new ValidationError(
"Unexpected number of Assertion signatures found. SAML Response rejected.",
ValidationError::WRONG_NUMBER_OF_SIGNATURES_IN_ASSERTION
);
}
}
return true;
}
/**
* Extracts a node from the DOMDocument (Assertion).
*
* @param string $assertionXpath Xpath Expression
*
* @return DOMNodeList The queried node
*/
protected function _queryAssertion($assertionXpath)
{
if ($this->encrypted) {
$xpath = new DOMXPath($this->decryptedDocument);
} else {
$xpath = new DOMXPath($this->document);
}
$xpath->registerNamespace('samlp', Constants::NS_SAMLP);
$xpath->registerNamespace('saml', Constants::NS_SAML);
$xpath->registerNamespace('ds', Constants::NS_DS);
$xpath->registerNamespace('xenc', Constants::NS_XENC);
$assertionNode = '/samlp:Response/saml:Assertion';
$signatureQuery = $assertionNode . '/ds:Signature/ds:SignedInfo/ds:Reference';
$assertionReferenceNode = $xpath->query($signatureQuery)->item(0);
if (!$assertionReferenceNode) {
// is the response signed as a whole?
$signatureQuery = '/samlp:Response/ds:Signature/ds:SignedInfo/ds:Reference';
$responseReferenceNode = $xpath->query($signatureQuery)->item(0);
if ($responseReferenceNode) {
$uri = $responseReferenceNode->attributes->getNamedItem('URI')->nodeValue;
if (empty($uri)) {
$id = $responseReferenceNode->parentNode->parentNode->parentNode->attributes->getNamedItem('ID')->nodeValue;
} else {
$id = substr($responseReferenceNode->attributes->getNamedItem('URI')->nodeValue, 1);
}
$nameQuery = "/samlp:Response[@ID='$id']/saml:Assertion" . $assertionXpath;
} else {
$nameQuery = "/samlp:Response/saml:Assertion" . $assertionXpath;
}
} else {
$uri = $assertionReferenceNode->attributes->getNamedItem('URI')->nodeValue;
if (empty($uri)) {
$id = $assertionReferenceNode->parentNode->parentNode->parentNode->attributes->getNamedItem('ID')->nodeValue;
} else {
$id = substr($assertionReferenceNode->attributes->getNamedItem('URI')->nodeValue, 1);
}
$nameQuery = $assertionNode."[@ID='$id']" . $assertionXpath;
}
return $xpath->query($nameQuery);
}
/**
* Extracts nodes that match the query from the DOMDocument (Response Menssage)
*
* @param string $query Xpath Expression
*
* @return DOMNodeList The queried nodes
*/
private function _query($query)
{
if ($this->encrypted) {
return Utils::query($this->decryptedDocument, $query);
} else {
return Utils::query($this->document, $query);
}
}
/**
* Decrypts the Assertion (DOMDocument)
*
* @param \DomNode $dom DomDocument
*
* @return DOMDocument Decrypted Assertion
*
* @throws Exception
* @throws ValidationError
*/
protected function decryptAssertion(\DomNode $dom)
{
$pem = $this->_settings->getSPkey();
if (empty($pem)) {
throw new Error(
"No private key available, check settings",
Error::PRIVATE_KEY_NOT_FOUND
);
}
$objenc = new XMLSecEnc();
$encData = $objenc->locateEncryptedData($dom);
if (!$encData) {
throw new ValidationError(
"Cannot locate encrypted assertion",
ValidationError::MISSING_ENCRYPTED_ELEMENT
);
}
$objenc->setNode($encData);
$objenc->type = $encData->getAttribute("Type");
if (!$objKey = $objenc->locateKey()) {
throw new ValidationError(
"Unknown algorithm",
ValidationError::KEY_ALGORITHM_ERROR
);
}
$key = null;
if ($objKeyInfo = $objenc->locateKeyInfo($objKey)) {
if ($objKeyInfo->isEncrypted) {
$objencKey = $objKeyInfo->encryptedCtx;
$objKeyInfo->loadKey($pem, false, false);
$key = $objencKey->decryptKey($objKeyInfo);
} else {
// symmetric encryption key support
$objKeyInfo->loadKey($pem, false, false);
}
}
if (empty($objKey->key)) {
$objKey->loadKey($key);
}
$decryptedXML = $objenc->decryptNode($objKey, false);
$decrypted = new DOMDocument();
$check = Utils::loadXML($decrypted, $decryptedXML);
if ($check === false) {
throw new Exception('Error: string from decrypted assertion could not be loaded into a XML document');
}
if ($encData->parentNode instanceof DOMDocument) {
return $decrypted;
} else {
$decrypted = $decrypted->documentElement;
$encryptedAssertion = $encData->parentNode;
$container = $encryptedAssertion->parentNode;
// Fix possible issue with saml namespace
if (!$decrypted->hasAttributeNS('http://www.w3.org/2000/xmlns/', 'xmlns:saml')
&& !$decrypted->hasAttributeNS('http://www.w3.org/2000/xmlns/', 'xmlns:saml2')
&& !$decrypted->hasAttributeNS('http://www.w3.org/2000/xmlns/', 'xmlns')
&& !$container->hasAttributeNS('http://www.w3.org/2000/xmlns/', 'xmlns:saml')
&& !$container->hasAttributeNS('http://www.w3.org/2000/xmlns/', 'xmlns:saml2')
) {
if (strpos($encryptedAssertion->tagName, 'saml2:') !== false) {
$ns = 'xmlns:saml2';
} else if (strpos($encryptedAssertion->tagName, 'saml:') !== false) {
$ns = 'xmlns:saml';
} else {
$ns = 'xmlns';
}
$decrypted->setAttributeNS('http://www.w3.org/2000/xmlns/', $ns, Constants::NS_SAML);
}
Utils::treeCopyReplace($encryptedAssertion, $decrypted);
// Rebuild the DOM will fix issues with namespaces as well
$dom = new DOMDocument();
return Utils::loadXML($dom, $container->ownerDocument->saveXML());
}
}
/**
* After execute a validation process, if fails this method returns the cause
*
* @return Exception|null Cause
*/
public function getErrorException()
{
return $this->_error;
}
/**
* After execute a validation process, if fails this method returns the cause
*
* @return null|string Error reason
*/
public function getError()
{
$errorMsg = null;
if (isset($this->_error)) {
$errorMsg = htmlentities($this->_error->getMessage());
}
return $errorMsg;
}
/**
* Returns the SAML Response document (If contains an encrypted assertion, decrypts it)
*
* @return DomDocument SAML Response
*/
public function getXMLDocument()
{
if ($this->encrypted) {
return $this->decryptedDocument;
} else {
return $this->document;
}
}
}