Import EncryptedElementTrait from saml2-library

Author: tvdijen

src/XML/EncryptedElementTrait.php

@@ -0,0 +1,195 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SimpleSAML\XMLSecurity\XML;
+
+use DOMElement;
+use SimpleSAML\Assert\Assert;
+use SimpleSAML\XML\AbstractXMLElement;
+use SimpleSAML\XML\Exception\InvalidDOMElementException;
+use SimpleSAML\XMLSecurity\XML\xenc\EncryptedData;
+use SimpleSAML\XMLSecurity\XML\xenc\EncryptedKey;
+use SimpleSAML\XMLSecurity\XMLSecEnc;
+use SimpleSAML\XMLSecurity\XMLSecurityKey;
+
+/**
+ * Trait aggregating functionality for encrypted elements.
+ *
+ * @package simplesamlphp/saml2
+ */
+trait EncryptedElementTrait
+{
+    /**
+     * The current encrypted ID.
+     *
+     * @var \SimpleSAML\XMLSecurity\XML\xenc\EncryptedData
+     * @psalm-suppress PropertyNotSetInConstructor
+     */
+    protected EncryptedData $encryptedData;
+
+    /**
+     * A list of encrypted keys.
+     *
+     * @var \SimpleSAML\XMLSecurity\XML\xenc\EncryptedKey[]
+     */
+    protected array $encryptedKeys = [];
+
+
+    /**
+     * Constructor for encrypted elements.
+     *
+     * @param \SimpleSAML\XMLSecurity\XML\xenc\EncryptedData $encryptedData The EncryptedData object.
+     * @param \SimpleSAML\XMLSecurity\XML\xenc\EncryptedKey[] $encryptedKeys An array of zero or more EncryptedKey objects.
+     */
+    public function __construct(EncryptedData $encryptedData, array $encryptedKeys)
+    {
+        $this->setEncryptedData($encryptedData);
+        $this->setEncryptedKeys($encryptedKeys);
+    }
+
+
+    /**
+     * Get the EncryptedData object.
+     *
+     * @return \SimpleSAML\XMLSecurity\XML\xenc\EncryptedData
+     */
+    public function getEncryptedData(): EncryptedData
+    {
+        return $this->encryptedData;
+    }
+
+
+    /**
+     * @param \SimpleSAML\XMLSecurity\XML\xenc\EncryptedData $encryptedData
+     */
+    protected function setEncryptedData(EncryptedData $encryptedData): void
+    {
+        $this->encryptedData = $encryptedData;
+    }
+
+
+    /**
+     * Get the array of EncryptedKey objects
+     *
+     * @return \SimpleSAML\XMLSecurity\XML\xenc\EncryptedKey[]
+     */
+    public function getEncryptedKeys(): array
+    {
+        return $this->encryptedKeys;
+    }
+
+
+    /**
+     * @param \SimpleSAML\XMLSecurity\XML\xenc\EncryptedKey[] $encryptedKeys
+     */
+    protected function setEncryptedKeys(array $encryptedKeys): void
+    {
+        Assert::allIsInstanceOf(
+            $encryptedKeys,
+            EncryptedKey::class,
+            'All encrypted keys in <' . $this->getQualifiedName() . '> must be an instance of EncryptedKey.'
+        );
+
+        $this->encryptedKeys = $encryptedKeys;
+    }
+
+
+    /**
+     * Create an encrypted element from a given unencrypted element and a key.
+     *
+     * @param \SimpleSAML\XML\AbstractXMLElement $element
+     * @param \SimpleSAML\XMLSecurity\XMLSecurityKey $key
+     *
+     * @return \SimpleSAML\XMLSecurity\XML\EncryptedElementInterface
+     * @throws \Exception
+     */
+    public static function fromUnencryptedElement(
+        AbstractXMLElement $element,
+        XMLSecurityKey $key
+    ): EncryptedElementInterface {
+        $xml = $element->toXML();
+
+        $enc = new XMLSecEnc();
+        $enc->setNode($xml);
+        $enc->type = XMLSecEnc::Element;
+
+        switch ($key->type) {
+            case XMLSecurityKey::TRIPLEDES_CBC:
+            case XMLSecurityKey::AES128_CBC:
+            case XMLSecurityKey::AES192_CBC:
+            case XMLSecurityKey::AES256_CBC:
+            case XMLSecurityKey::AES128_GCM:
+            case XMLSecurityKey::AES192_GCM:
+            case XMLSecurityKey::AES256_GCM:
+                $symmetricKey = $key;
+                break;
+
+            case XMLSecurityKey::RSA_1_5:
+            case XMLSecurityKey::RSA_SHA1:
+            case XMLSecurityKey::RSA_SHA256:
+            case XMLSecurityKey::RSA_SHA384:
+            case XMLSecurityKey::RSA_SHA512:
+            case XMLSecurityKey::RSA_OAEP:
+            case XMLSecurityKey::RSA_OAEP_MGF1P:
+                $symmetricKey = new XMLSecurityKey(XMLSecurityKey::AES128_CBC);
+                $symmetricKey->generateSessionKey();
+
+                $enc->encryptKey($key, $symmetricKey);
+
+                break;
+
+            default:
+                throw new \Exception('Unknown key type for encryption: ' . $key->type);
+        }
+
+        $dom = $enc->encryptNode($symmetricKey);
+        /** @var \SimpleSAML\XMLSecurity\XML\xenc\EncryptedData $encData */
+        $encData = EncryptedData::fromXML($dom);
+        return new static($encData, []);
+    }
+
+
+    /**
+     * @inheritDoc
+     * @return \SimpleSAML\XMLSecurity\XML\EncryptedElementInterface
+     *
+     * @throws \SimpleSAML\XML\Exception\InvalidDOMElementException if the qualified name of the supplied element is wrong
+     */
+    public static function fromXML(DOMElement $xml): object
+    {
+        Assert::same($xml->localName, AbstractXMLElement::getClassName(static::class), InvalidDOMElementException::class);
+        Assert::same($xml->namespaceURI, static::NS, InvalidDOMElementException::class);
+
+        $ed = EncryptedData::getChildrenOfClass($xml);
+        Assert::count($ed, 1, 'No more or less than one EncryptedData element allowed in ' .
+            AbstractXMLElement::getClassName(static::class) . '.');
+
+        $ek = EncryptedKey::getChildrenOfClass($xml);
+
+        return new static($ed[0], $ek);
+    }
+
+
+    /**
+     * @inheritDoc
+     */
+    public function toXML(DOMElement $parent = null): DOMElement
+    {
+        $e = $this->instantiateParentElement($parent);
+
+        $this->encryptedData->toXML($e);
+
+        foreach ($this->encryptedKeys as $key) {
+            $key->toXML($e);
+        }
+
+        return $e;
+    }
+
+
+    abstract public function instantiateParentElement(DOMElement $parent = null): DOMElement;
+
+
+    abstract public function getQualifiedName(): string;
+}