Assertion.php

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<?php

namespace SAML2;

use RobRichards\XMLSecLibs\XMLSecEnc;
use RobRichards\XMLSecLibs\XMLSecurityKey;
use SAML2\Exception\RuntimeException;
use SAML2\Utilities\Temporal;
use SAML2\XML\Chunk;
use SAML2\XML\saml\SubjectConfirmation;

class Assertion implements SignedElement
{
    private $id;

    private $issueInstant;

    private $issuer;

    private $nameId;

    private $encryptedNameId;

    private $encryptedAttributes;

    private $encryptionKey;

    private $notBefore;

    private $notOnOrAfter;

    private $validAudiences;

    private $sessionNotOnOrAfter;

    private $sessionIndex;

    private $authnInstant;

    private $authnContextClassRef;

    private $authnContextDecl;

    private $authnContextDeclRef;

    private $AuthenticatingAuthority;

    private $attributes;

    private $attributesValueTypes;

    private $nameFormat;

    private $signatureKey;

    private $certificates;

    private $signatureData;

    private $requiredEncAttributes;

    private $SubjectConfirmation;

    protected $wasSignedAtConstruction = false;

    private $signatureMethod;

    public function __construct(\DOMElement $xml = null)
    {
        $this->id = Utils::getContainer()->generateId();
        $this->issueInstant = Temporal::getTime();
        $this->issuer = '';
        $this->authnInstant = Temporal::getTime();
        $this->attributes = array();
        $this->nameFormat = Constants::NAMEFORMAT_UNSPECIFIED;
        $this->certificates = array();
        $this->AuthenticatingAuthority = array();
        $this->SubjectConfirmation = array();
        $this->requiredEncAttributes = false;

        if ($xml === null) {
            return;
        }

        if (!$xml->hasAttribute('ID')) {
            throw new \Exception('Missing ID attribute on SAML assertion.');
        }
        $this->id = $xml->getAttribute('ID');

        if ($xml->getAttribute('Version') !== '2.0') {
            /* Currently a very strict check. */
            throw new \Exception('Unsupported version: ' . $xml->getAttribute('Version'));
        }

        $this->issueInstant = Utils::xsDateTimeToTimestamp($xml->getAttribute('IssueInstant'));

        $issuer = Utils::xpQuery($xml, './saml_assertion:Issuer');
        if (empty($issuer)) {
            throw new \Exception('Missing <saml:Issuer> in assertion.');
        }
        $this->issuer = new XML\saml\Issuer($issuer[0]);
        if ($this->issuer->Format === Constants::NAMEID_ENTITY) {
            $this->issuer = $this->issuer->value;
        }

        $this->parseSubject($xml);
        $this->parseConditions($xml);
        $this->parseAuthnStatement($xml);
        $this->parseAttributes($xml);
        $this->parseEncryptedAttributes($xml);
        $this->parseSignature($xml);
    }

    private function parseSubject(\DOMElement $xml)
    {
        $subject = Utils::xpQuery($xml, './saml_assertion:Subject');
        if (empty($subject)) {
            /* No Subject node. */

            return;
        } elseif (count($subject) > 1) {
            throw new \Exception('More than one <saml:Subject> in <saml:Assertion>.');
        }
        $subject = $subject[0];

        $nameId = Utils::xpQuery(
            $subject,
            './saml_assertion:NameID | ./saml_assertion:EncryptedID/xenc:EncryptedData'
        );
        if (count($nameId) > 1) {
            throw new \Exception('More than one <saml:NameID> or <saml:EncryptedID> in <saml:Subject>.');
        } elseif (!empty($nameId)) {
            $nameId = $nameId[0];
            if ($nameId->localName === 'EncryptedData') {
                /* The NameID element is encrypted. */
                $this->encryptedNameId = $nameId;
            } else {
                $this->nameId = new XML\saml\NameID($nameId);
            }
        }

        $subjectConfirmation = Utils::xpQuery($subject, './saml_assertion:SubjectConfirmation');
        if (empty($subjectConfirmation) && empty($nameId)) {
            throw new \Exception('Missing <saml:SubjectConfirmation> in <saml:Subject>.');
        }

        foreach ($subjectConfirmation as $sc) {
            $this->SubjectConfirmation[] = new SubjectConfirmation($sc);
        }
    }

    private function parseConditions(\DOMElement $xml)
    {
        $conditions = Utils::xpQuery($xml, './saml_assertion:Conditions');
        if (empty($conditions)) {
            /* No <saml:Conditions> node. */

            return;
        } elseif (count($conditions) > 1) {
            throw new \Exception('More than one <saml:Conditions> in <saml:Assertion>.');
        }
        $conditions = $conditions[0];

        if ($conditions->hasAttribute('NotBefore')) {
            $notBefore = Utils::xsDateTimeToTimestamp($conditions->getAttribute('NotBefore'));
            if ($this->notBefore === null || $this->notBefore < $notBefore) {
                $this->notBefore = $notBefore;
            }
        }
        if ($conditions->hasAttribute('NotOnOrAfter')) {
            $notOnOrAfter = Utils::xsDateTimeToTimestamp($conditions->getAttribute('NotOnOrAfter'));
            if ($this->notOnOrAfter === null || $this->notOnOrAfter > $notOnOrAfter) {
                $this->notOnOrAfter = $notOnOrAfter;
            }
        }

        for ($node = $conditions->firstChild; $node !== null; $node = $node->nextSibling) {
            if ($node instanceof \DOMText) {
                continue;
            }
            if ($node->namespaceURI !== Constants::NS_SAML) {
                throw new \Exception('Unknown namespace of condition: ' . var_export($node->namespaceURI, true));
            }
            switch ($node->localName) {
                case 'AudienceRestriction':
                    $audiences = Utils::extractStrings($node, Constants::NS_SAML, 'Audience');
                    if ($this->validAudiences === null) {
                        /* The first (and probably last) AudienceRestriction element. */
                        $this->validAudiences = $audiences;
                    } else {
                        /*
                         * The set of AudienceRestriction are ANDed together, so we need
                         * the subset that are present in all of them.
                         */
                        $this->validAudiences = array_intersect($this->validAudiences, $audiences);
                    }
                    break;
                case 'OneTimeUse':
                    /* Currently ignored. */
                    break;
                case 'ProxyRestriction':
                    /* Currently ignored. */
                    break;
                default:
                    throw new \Exception('Unknown condition: ' . var_export($node->localName, true));
            }
        }
    }

    private function parseAuthnStatement(\DOMElement $xml)
    {
        $authnStatements = Utils::xpQuery($xml, './saml_assertion:AuthnStatement');
        if (empty($authnStatements)) {
            $this->authnInstant = null;

            return;
        } elseif (count($authnStatements) > 1) {
            throw new \Exception('More than one <saml:AuthnStatement> in <saml:Assertion> not supported.');
        }
        $authnStatement = $authnStatements[0];

        if (!$authnStatement->hasAttribute('AuthnInstant')) {
            throw new \Exception('Missing required AuthnInstant attribute on <saml:AuthnStatement>.');
        }
        $this->authnInstant = Utils::xsDateTimeToTimestamp($authnStatement->getAttribute('AuthnInstant'));

        if ($authnStatement->hasAttribute('SessionNotOnOrAfter')) {
            $this->sessionNotOnOrAfter = Utils::xsDateTimeToTimestamp($authnStatement->getAttribute('SessionNotOnOrAfter'));
        }

        if ($authnStatement->hasAttribute('SessionIndex')) {
            $this->sessionIndex = $authnStatement->getAttribute('SessionIndex');
        }

        $this->parseAuthnContext($authnStatement);
    }

    private function parseAuthnContext(\DOMElement $authnStatementEl)
    {
        // Get the AuthnContext element
        $authnContexts = Utils::xpQuery($authnStatementEl, './saml_assertion:AuthnContext');
        if (count($authnContexts) > 1) {
            throw new \Exception('More than one <saml:AuthnContext> in <saml:AuthnStatement>.');
        } elseif (empty($authnContexts)) {
            throw new \Exception('Missing required <saml:AuthnContext> in <saml:AuthnStatement>.');
        }
        $authnContextEl = $authnContexts[0];

        // Get the AuthnContextDeclRef (if available)
        $authnContextDeclRefs = Utils::xpQuery($authnContextEl, './saml_assertion:AuthnContextDeclRef');
        if (count($authnContextDeclRefs) > 1) {
            throw new \Exception(
                'More than one <saml:AuthnContextDeclRef> found?'
            );
        } elseif (count($authnContextDeclRefs) === 1) {
            $this->setAuthnContextDeclRef(trim($authnContextDeclRefs[0]->textContent));
        }

        // Get the AuthnContextDecl (if available)
        $authnContextDecls = Utils::xpQuery($authnContextEl, './saml_assertion:AuthnContextDecl');
        if (count($authnContextDecls) > 1) {
            throw new \Exception(
                'More than one <saml:AuthnContextDecl> found?'
            );
        } elseif (count($authnContextDecls) === 1) {
            $this->setAuthnContextDecl(new Chunk($authnContextDecls[0]));
        }

        // Get the AuthnContextClassRef (if available)
        $authnContextClassRefs = Utils::xpQuery($authnContextEl, './saml_assertion:AuthnContextClassRef');
        if (count($authnContextClassRefs) > 1) {
            throw new \Exception('More than one <saml:AuthnContextClassRef> in <saml:AuthnContext>.');
        } elseif (count($authnContextClassRefs) === 1) {
            $this->setAuthnContextClassRef(trim($authnContextClassRefs[0]->textContent));
        }

        // Constraint from XSD: MUST have one of the three
        if (empty($this->authnContextClassRef) && empty($this->authnContextDecl) && empty($this->authnContextDeclRef)) {
            throw new \Exception(
                'Missing either <saml:AuthnContextClassRef> or <saml:AuthnContextDeclRef> or <saml:AuthnContextDecl>'
            );
        }

        $this->AuthenticatingAuthority = Utils::extractStrings(
            $authnContextEl,
            Constants::NS_SAML,
            'AuthenticatingAuthority'
        );
    }

    private function parseAttributes(\DOMElement $xml)
    {
        $firstAttribute = true;
        $attributes = Utils::xpQuery($xml, './saml_assertion:AttributeStatement/saml_assertion:Attribute');
        foreach ($attributes as $attribute) {
            if (!$attribute->hasAttribute('Name')) {
                throw new \Exception('Missing name on <saml:Attribute> element.');
            }
            $name = $attribute->getAttribute('Name');

            if ($attribute->hasAttribute('NameFormat')) {
                $nameFormat = $attribute->getAttribute('NameFormat');
            } else {
                $nameFormat = Constants::NAMEFORMAT_UNSPECIFIED;
            }

            if ($firstAttribute) {
                $this->nameFormat = $nameFormat;
                $firstAttribute = false;
            } else {
                if ($this->nameFormat !== $nameFormat) {
                    $this->nameFormat = Constants::NAMEFORMAT_UNSPECIFIED;
                }
            }

            if (!array_key_exists($name, $this->attributes)) {
                $this->attributes[$name] = array();
                $this->attributesValueTypes[$name] = array();
            }

            $this->parseAttributeValue($attribute, $name);
        }
    }

    private function parseAttributeValue($attribute, $attributeName)
    {
        $values = Utils::xpQuery($attribute, './saml_assertion:AttributeValue');

        if ($attributeName === Constants::EPTI_URN_MACE || $attributeName === Constants::EPTI_URN_OID) {
            foreach ($values as $index => $eptiAttributeValue) {
                $eptiNameId = Utils::xpQuery($eptiAttributeValue, './saml_assertion:NameID');

                if (count($eptiNameId) !== 1) {
                    throw new RuntimeException(sprintf(
                        'A "%s" (EPTI) attribute value must be a NameID, none found for value no. "%d"',
                        $attributeName,
                        $index
                    ));
                }

                $this->attributes[$attributeName][] = new XML\saml\NameID($eptiNameId[0]);
            }

            return;
        }

        foreach ($values as $value) {
            $hasNonTextChildElements = false;
            foreach ($value->childNodes as $childNode) {
                if ($childNode->nodeType !== XML_TEXT_NODE) {
                    $hasNonTextChildElements = true;
                    break;
                }
            }

            $type = $value->getAttribute('xsi:type');
            if ($type === '') {
                $type = null;
            }
            $this->attributesValueTypes[$attributeName][] = $type;

            if ($hasNonTextChildElements) {
                $this->attributes[$attributeName][] = $value->childNodes;
                continue;
            }
            
            if ($type === 'xs:integer') {
                $this->attributes[$attributeName][] = (int)$value->textContent;
            } else {
                $this->attributes[$attributeName][] = trim($value->textContent);
            }
        }
    }

    private function parseEncryptedAttributes(\DOMElement $xml)
    {
        $this->encryptedAttributes = Utils::xpQuery(
            $xml,
            './saml_assertion:AttributeStatement/saml_assertion:EncryptedAttribute'
        );
    }

    private function parseSignature(\DOMElement $xml)
    {
        $signatureMethod = Utils::xpQuery($xml, './ds:Signature/ds:SignedInfo/ds:SignatureMethod/@Algorithm');

        /* Validate the signature element of the message. */
        $sig = Utils::validateElement($xml);
        if ($sig !== false) {
            $this->wasSignedAtConstruction = true;
            $this->certificates = $sig['Certificates'];
            $this->signatureData = $sig;
            $this->signatureMethod = $signatureMethod[0]->value;
        }
    }

    public function validate(XMLSecurityKey $key)
    {
        assert($key->type === \RobRichards\XMLSecLibs\XMLSecurityKey::RSA_SHA1);

        if ($this->signatureData === null) {
            return false;
        }

        Utils::validateSignature($this->signatureData, $key);

        return true;
    }

    public function getId()
    {
        return $this->id;
    }

    public function setId($id)
    {
        assert(is_string($id));

        $this->id = $id;
    }

    public function getIssueInstant()
    {
        return $this->issueInstant;
    }

    public function setIssueInstant($issueInstant)
    {
        assert(is_int($issueInstant));

        $this->issueInstant = $issueInstant;
    }

    public function getIssuer()
    {
        return $this->issuer;
    }

    public function setIssuer($issuer)
    {
        assert(is_string($issuer) || $issuer instanceof XML\saml\Issuer);

        $this->issuer = $issuer;
    }

    public function getNameId()
    {
        if ($this->encryptedNameId !== null) {
            throw new \Exception('Attempted to retrieve encrypted NameID without decrypting it first.');
        }

        return $this->nameId;
    }

    public function setNameId($nameId)
    {
        assert(is_array($nameId) || is_null($nameId) || $nameId instanceof XML\saml\NameID);

        if (is_array($nameId)) {
            $nameId = XML\saml\NameID::fromArray($nameId);
        }
        $this->nameId = $nameId;
    }

    public function isNameIdEncrypted()
    {
        return $this->encryptedNameId !== null;
    }

    public function encryptNameId(XMLSecurityKey $key)
    {
        /* First create a XML representation of the NameID. */
        $doc = DOMDocumentFactory::create();
        $root = $doc->createElement('root');
        $doc->appendChild($root);
        $this->nameId->toXML($root);
        $nameId = $root->firstChild;

        Utils::getContainer()->debugMessage($nameId, 'encrypt');

        /* Encrypt the NameID. */
        $enc = new XMLSecEnc();
        $enc->setNode($nameId);
        // @codingStandardsIgnoreStart
        $enc->type = XMLSecEnc::Element;
        // @codingStandardsIgnoreEnd

        $symmetricKey = new XMLSecurityKey(XMLSecurityKey::AES128_CBC);
        $symmetricKey->generateSessionKey();
        $enc->encryptKey($key, $symmetricKey);

        $this->encryptedNameId = $enc->encryptNode($symmetricKey);
        $this->nameId = null;
    }

    public function decryptNameId(XMLSecurityKey $key, array $blacklist = array())
    {
        if ($this->encryptedNameId === null) {
            /* No NameID to decrypt. */

            return;
        }

        $nameId = Utils::decryptElement($this->encryptedNameId, $key, $blacklist);
        Utils::getContainer()->debugMessage($nameId, 'decrypt');
        $this->nameId = new XML\saml\NameID($nameId);

        $this->encryptedNameId = null;
    }

    public function hasEncryptedAttributes()
    {
        return $this->encryptedAttributes !== null;
    }

    public function decryptAttributes(XMLSecurityKey $key, array $blacklist = array())
    {
        if ($this->encryptedAttributes === null) {
            return;
        }
        $firstAttribute = true;
        $attributes = $this->encryptedAttributes;
        foreach ($attributes as $attributeEnc) {
            /*Decrypt node <EncryptedAttribute>*/
            $attribute = Utils::decryptElement(
                $attributeEnc->getElementsByTagName('EncryptedData')->item(0),
                $key,
                $blacklist
            );

            if (!$attribute->hasAttribute('Name')) {
                throw new \Exception('Missing name on <saml:Attribute> element.');
            }
            $name = $attribute->getAttribute('Name');

            if ($attribute->hasAttribute('NameFormat')) {
                $nameFormat = $attribute->getAttribute('NameFormat');
            } else {
                $nameFormat = Constants::NAMEFORMAT_UNSPECIFIED;
            }

            if ($firstAttribute) {
                $this->nameFormat = $nameFormat;
                $firstAttribute = false;
            } else {
                if ($this->nameFormat !== $nameFormat) {
                    $this->nameFormat = Constants::NAMEFORMAT_UNSPECIFIED;
                }
            }

            if (!array_key_exists($name, $this->attributes)) {
                $this->attributes[$name] = array();
            }

            $this->parseAttributeValue($attribute, $name);
        }
    }

    public function getNotBefore()
    {
        return $this->notBefore;
    }

    public function setNotBefore($notBefore)
    {
        assert(is_int($notBefore) || is_null($notBefore));

        $this->notBefore = $notBefore;
    }

    public function getNotOnOrAfter()
    {
        return $this->notOnOrAfter;
    }

    public function setNotOnOrAfter($notOnOrAfter)
    {
        assert(is_int($notOnOrAfter) || is_null($notOnOrAfter));

        $this->notOnOrAfter = $notOnOrAfter;
    }

    public function setEncryptedAttributes($ea)
    {
        $this->requiredEncAttributes = $ea;
    }

    public function getValidAudiences()
    {
        return $this->validAudiences;
    }

    public function setValidAudiences(array $validAudiences = null)
    {
        $this->validAudiences = $validAudiences;
    }

    public function getAuthnInstant()
    {
        return $this->authnInstant;
    }


    public function setAuthnInstant($authnInstant)
    {
        assert(is_int($authnInstant) || is_null($authnInstant));

        $this->authnInstant = $authnInstant;
    }

    public function getSessionNotOnOrAfter()
    {
        return $this->sessionNotOnOrAfter;
    }

    public function setSessionNotOnOrAfter($sessionNotOnOrAfter)
    {
        assert(is_int($sessionNotOnOrAfter) || is_null($sessionNotOnOrAfter));

        $this->sessionNotOnOrAfter = $sessionNotOnOrAfter;
    }

    public function getSessionIndex()
    {
        return $this->sessionIndex;
    }

    public function setSessionIndex($sessionIndex)
    {
        assert(is_string($sessionIndex) || is_null($sessionIndex));

        $this->sessionIndex = $sessionIndex;
    }

    public function getAuthnContext()
    {
        if (!empty($this->authnContextClassRef)) {
            return $this->authnContextClassRef;
        }
        if (!empty($this->authnContextDeclRef)) {
            return $this->authnContextDeclRef;
        }
        return null;
    }

    public function setAuthnContext($authnContext)
    {
        $this->setAuthnContextClassRef($authnContext);
    }

    public function getAuthnContextClassRef()
    {
        return $this->authnContextClassRef;
    }

    public function setAuthnContextClassRef($authnContextClassRef)
    {
        assert(is_string($authnContextClassRef) || is_null($authnContextClassRef));

        $this->authnContextClassRef = $authnContextClassRef;
    }

    public function setAuthnContextDecl(Chunk $authnContextDecl)
    {
        if (!empty($this->authnContextDeclRef)) {
            throw new \Exception(
                'AuthnContextDeclRef is already registered! May only have either a Decl or a DeclRef, not both!'
            );
        }

        $this->authnContextDecl = $authnContextDecl;
    }

    public function getAuthnContextDecl()
    {
        return $this->authnContextDecl;
    }

    public function setAuthnContextDeclRef($authnContextDeclRef)
    {
        if (!empty($this->authnContextDecl)) {
            throw new \Exception(
                'AuthnContextDecl is already registered! May only have either a Decl or a DeclRef, not both!'
            );
        }

        $this->authnContextDeclRef = $authnContextDeclRef;
    }

    public function getAuthnContextDeclRef()
    {
        return $this->authnContextDeclRef;
    }

    public function getAuthenticatingAuthority()
    {
        return $this->AuthenticatingAuthority;
    }

    public function setAuthenticatingAuthority($authenticatingAuthority)
    {
        $this->AuthenticatingAuthority = $authenticatingAuthority;
    }

    public function getAttributes()
    {
        return $this->attributes;
    }

    public function setAttributes(array $attributes)
    {
        $this->attributes = $attributes;
    }

    public function getAttributesValueTypes()
    {
        return $this->attributesValueTypes;
    }

    public function setAttributesValueTypes(array $attributesValueTypes)
    {
        $this->attributesValueTypes = $attributesValueTypes;
    }

    public function getAttributeNameFormat()
    {
        return $this->nameFormat;
    }

    public function setAttributeNameFormat($nameFormat)
    {
        assert(is_string($nameFormat));

        $this->nameFormat = $nameFormat;
    }

    public function getSubjectConfirmation()
    {
        return $this->SubjectConfirmation;
    }

    public function setSubjectConfirmation(array $SubjectConfirmation)
    {
        $this->SubjectConfirmation = $SubjectConfirmation;
    }

    public function getSignatureKey()
    {
        return $this->signatureKey;
    }

    public function setSignatureKey(XMLSecurityKey $signatureKey = null)
    {
        $this->signatureKey = $signatureKey;
    }

    public function getEncryptionKey()
    {
        return $this->encryptionKey;
    }

    public function setEncryptionKey(XMLSecurityKey $Key = null)
    {
        $this->encryptionKey = $Key;
    }

    public function setCertificates(array $certificates)
    {
        $this->certificates = $certificates;
    }

    public function getCertificates()
    {
        return $this->certificates;
    }

    public function getWasSignedAtConstruction()
    {
        return $this->wasSignedAtConstruction;
    }

    public function getSignatureMethod()
    {
        return $this->signatureMethod;
    }

    public function toXML(\DOMNode $parentElement = null)
    {
        if ($parentElement === null) {
            $document = DOMDocumentFactory::create();
            $parentElement = $document;
        } else {
            $document = $parentElement->ownerDocument;
        }

        $root = $document->createElementNS(Constants::NS_SAML, 'saml:' . 'Assertion');
        $parentElement->appendChild($root);

        /* Ugly hack to add another namespace declaration to the root element. */
        $root->setAttributeNS(Constants::NS_SAMLP, 'samlp:tmp', 'tmp');
        $root->removeAttributeNS(Constants::NS_SAMLP, 'tmp');
        $root->setAttributeNS(Constants::NS_XSI, 'xsi:tmp', 'tmp');
        $root->removeAttributeNS(Constants::NS_XSI, 'tmp');
        $root->setAttributeNS(Constants::NS_XS, 'xs:tmp', 'tmp');
        $root->removeAttributeNS(Constants::NS_XS, 'tmp');

        $root->setAttribute('ID', $this->id);
        $root->setAttribute('Version', '2.0');
        $root->setAttribute('IssueInstant', gmdate('Y-m-d\TH:i:s\Z', $this->issueInstant));

        if (is_string($this->issuer)) {
            $issuer = Utils::addString($root, Constants::NS_SAML, 'saml:Issuer', $this->issuer);
        } elseif ($this->issuer instanceof XML\saml\Issuer) {
            $issuer = $this->issuer->toXML($root);
        }

        $this->addSubject($root);
        $this->addConditions($root);
        $this->addAuthnStatement($root);
        if ($this->requiredEncAttributes === false) {
            $this->addAttributeStatement($root);
        } else {
            $this->addEncryptedAttributeStatement($root);
        }

        if ($this->signatureKey !== null) {
            Utils::insertSignature($this->signatureKey, $this->certificates, $root, $issuer->nextSibling);
        }

        return $root;
    }

    private function addSubject(\DOMElement $root)
    {
        if ($this->nameId === null && $this->encryptedNameId === null) {
            /* We don't have anything to create a Subject node for. */

            return;
        }

        $subject = $root->ownerDocument->createElementNS(Constants::NS_SAML, 'saml:Subject');
        $root->appendChild($subject);

        if ($this->encryptedNameId === null) {
            $this->nameId->toXML($subject);
        } else {
            $eid = $subject->ownerDocument->createElementNS(Constants::NS_SAML, 'saml:' . 'EncryptedID');
            $subject->appendChild($eid);
            $eid->appendChild($subject->ownerDocument->importNode($this->encryptedNameId, true));
        }

        foreach ($this->SubjectConfirmation as $sc) {
            $sc->toXML($subject);
        }
    }


    private function addConditions(\DOMElement $root)
    {
        $document = $root->ownerDocument;

        $conditions = $document->createElementNS(Constants::NS_SAML, 'saml:Conditions');
        $root->appendChild($conditions);

        if ($this->notBefore !== null) {
            $conditions->setAttribute('NotBefore', gmdate('Y-m-d\TH:i:s\Z', $this->notBefore));
        }
        if ($this->notOnOrAfter !== null) {
            $conditions->setAttribute('NotOnOrAfter', gmdate('Y-m-d\TH:i:s\Z', $this->notOnOrAfter));
        }

        if ($this->validAudiences !== null) {
            $ar = $document->createElementNS(Constants::NS_SAML, 'saml:AudienceRestriction');
            $conditions->appendChild($ar);

            Utils::addStrings($ar, Constants::NS_SAML, 'saml:Audience', false, $this->validAudiences);
        }
    }


    private function addAuthnStatement(\DOMElement $root)
    {
        if ($this->authnInstant === null ||
            (
                $this->authnContextClassRef === null &&
                $this->authnContextDecl === null &&
                $this->authnContextDeclRef === null
            )
        ) {
            /* No authentication context or AuthnInstant => no authentication statement. */

            return;
        }

        $document = $root->ownerDocument;

        $authnStatementEl = $document->createElementNS(Constants::NS_SAML, 'saml:AuthnStatement');
        $root->appendChild($authnStatementEl);

        $authnStatementEl->setAttribute('AuthnInstant', gmdate('Y-m-d\TH:i:s\Z', $this->authnInstant));

        if ($this->sessionNotOnOrAfter !== null) {
            $authnStatementEl->setAttribute('SessionNotOnOrAfter', gmdate('Y-m-d\TH:i:s\Z', $this->sessionNotOnOrAfter));
        }
        if ($this->sessionIndex !== null) {
            $authnStatementEl->setAttribute('SessionIndex', $this->sessionIndex);
        }

        $authnContextEl = $document->createElementNS(Constants::NS_SAML, 'saml:AuthnContext');
        $authnStatementEl->appendChild($authnContextEl);

        if (!empty($this->authnContextClassRef)) {
            Utils::addString(
                $authnContextEl,
                Constants::NS_SAML,
                'saml:AuthnContextClassRef',
                $this->authnContextClassRef
            );
        }
        if (!empty($this->authnContextDecl)) {
            $this->authnContextDecl->toXML($authnContextEl);
        }
        if (!empty($this->authnContextDeclRef)) {
            Utils::addString(
                $authnContextEl,
                Constants::NS_SAML,
                'saml:AuthnContextDeclRef',
                $this->authnContextDeclRef
            );
        }

        Utils::addStrings(
            $authnContextEl,
            Constants::NS_SAML,
            'saml:AuthenticatingAuthority',
            false,
            $this->AuthenticatingAuthority
        );
    }


    private function addAttributeStatement(\DOMElement $root)
    {
        if (empty($this->attributes)) {
            return;
        }

        $document = $root->ownerDocument;

        $attributeStatement = $document->createElementNS(Constants::NS_SAML, 'saml:AttributeStatement');
        $root->appendChild($attributeStatement);

        foreach ($this->attributes as $name => $values) {
            $attribute = $document->createElementNS(Constants::NS_SAML, 'saml:Attribute');
            $attributeStatement->appendChild($attribute);
            $attribute->setAttribute('Name', $name);

            if ($this->nameFormat !== Constants::NAMEFORMAT_UNSPECIFIED) {
                $attribute->setAttribute('NameFormat', $this->nameFormat);
            }

            // make sure eduPersonTargetedID can be handled properly as a NameID
            if ($name === Constants::EPTI_URN_MACE || $name === Constants::EPTI_URN_OID) {
                foreach ($values as $eptiValue) {
                    $attributeValue = $document->createElementNS(Constants::NS_SAML, 'saml:AttributeValue');
                    $attribute->appendChild($attributeValue);
                    if ($eptiValue instanceof XML\saml\NameID) {
                        $eptiValue->toXML($attributeValue);
                    } elseif ($eptiValue instanceof \DOMNodeList) {
                        $node = $root->ownerDocument->importNode($eptiValue->item(0), true);
                        $attributeValue->appendChild($node);
                    } else {
                        $attributeValue->textContent = $eptiValue;
                    }
                }

                continue;
            }

            // get value type(s) for the current attribute
            if (is_array($this->attributesValueTypes) && array_key_exists($name, $this->attributesValueTypes)) {
                $valueTypes = $this->attributesValueTypes[$name];
                if (is_array($valueTypes) && count($valueTypes) != count($values)) {
                    throw new \Exception('Array of value types and array of values have different size for attribute '. var_export($name, true));
                }
            } else {
                // if no type(s), default behaviour
                $valueTypes = null;
            }

            $vidx = -1;
            foreach ($values as $value) {
                $vidx++;

                // try to get type from current types
                $type = null;
                if (!is_null($valueTypes)) {
                    if (is_array($valueTypes)) {
                        $type = $valueTypes[$vidx];
                    } else {
                        $type = $valueTypes;
                    }
                }

                // if no type get from types, use default behaviour
                if (is_null($type)) {
                    if (is_string($value)) {
                        $type = 'xs:string';
                    } elseif (is_int($value)) {
                        $type = 'xs:integer';
                    } else {
                        $type = null;
                    }
                }

                $attributeValue = $document->createElementNS(Constants::NS_SAML, 'saml:AttributeValue');
                $attribute->appendChild($attributeValue);
                if ($type !== null) {
                    $attributeValue->setAttributeNS(Constants::NS_XSI, 'xsi:type', $type);
                }
                if (is_null($value)) {
                    $attributeValue->setAttributeNS(Constants::NS_XSI, 'xsi:nil', 'true');
                }

                if ($value instanceof \DOMNodeList) {
                    for ($i = 0; $i < $value->length; $i++) {
                        $node = $document->importNode($value->item($i), true);
                        $attributeValue->appendChild($node);
                    }
                } else {
                    $attributeValue->appendChild($document->createTextNode($value));
                }
            }
        }
    }


    private function addEncryptedAttributeStatement(\DOMElement $root)
    {
        if ($this->requiredEncAttributes === false) {
            return;
        }

        $document = $root->ownerDocument;

        $attributeStatement = $document->createElementNS(Constants::NS_SAML, 'saml:AttributeStatement');
        $root->appendChild($attributeStatement);

        foreach ($this->attributes as $name => $values) {
            $document2 = DOMDocumentFactory::create();
            $attribute = $document2->createElementNS(Constants::NS_SAML, 'saml:Attribute');
            $attribute->setAttribute('Name', $name);
            $document2->appendChild($attribute);

            if ($this->nameFormat !== Constants::NAMEFORMAT_UNSPECIFIED) {
                $attribute->setAttribute('NameFormat', $this->nameFormat);
            }

            foreach ($values as $value) {
                if (is_string($value)) {
                    $type = 'xs:string';
                } elseif (is_int($value)) {
                    $type = 'xs:integer';
                } else {
                    $type = null;
                }

                $attributeValue = $document2->createElementNS(Constants::NS_SAML, 'saml:AttributeValue');
                $attribute->appendChild($attributeValue);
                if ($type !== null) {
                    $attributeValue->setAttributeNS(Constants::NS_XSI, 'xsi:type', $type);
                }

                if ($value instanceof \DOMNodeList) {
                    for ($i = 0; $i < $value->length; $i++) {
                        $node = $document2->importNode($value->item($i), true);
                        $attributeValue->appendChild($node);
                    }
                } else {
                    $attributeValue->appendChild($document2->createTextNode($value));
                }
            }
            /*Once the attribute nodes are built, the are encrypted*/
            $EncAssert = new XMLSecEnc();
            $EncAssert->setNode($document2->documentElement);
            $EncAssert->type = 'http://www.w3.org/2001/04/xmlenc#Element';
            /*
             * Attributes are encrypted with a session key and this one with
             * $EncryptionKey
             */
            $symmetricKey = new XMLSecurityKey(XMLSecurityKey::AES256_CBC);
            $symmetricKey->generateSessionKey();
            $EncAssert->encryptKey($this->encryptionKey, $symmetricKey);
            $EncrNode = $EncAssert->encryptNode($symmetricKey);

            $EncAttribute = $document->createElementNS(Constants::NS_SAML, 'saml:EncryptedAttribute');
            $attributeStatement->appendChild($EncAttribute);
            $n = $document->importNode($EncrNode, true);
            $EncAttribute->appendChild($n);
        }
    }
}