+/*
+ * Copyright 2001-2006 Internet2
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Encrypter.cpp
+ *
+ * Methods for encrypting XMLObjects and other data.
+ */
+
+#include "internal.h"
+#include "encryption/Decrypter.h"
+
+#include <log4cpp/Category.hh>
+#include <xsec/enc/XSECCryptoException.hpp>
+#include <xsec/framework/XSECException.hpp>
+#include <xsec/framework/XSECAlgorithmMapper.hpp>
+#include <xsec/framework/XSECAlgorithmHandler.hpp>
+#include <xsec/xenc/XENCEncryptedData.hpp>
+#include <xsec/xenc/XENCEncryptedKey.hpp>
+
+using namespace xmlencryption;
+using namespace xmlsignature;
+using namespace xmltooling;
+using namespace std;
+
+Decrypter::~Decrypter()
+{
+ XMLToolingInternalConfig::getInternalConfig().m_xsecProvider->releaseCipher(m_cipher);
+ delete m_resolver;
+ delete m_KEKresolver;
+}
+
+DOMDocumentFragment* Decrypter::decryptData(EncryptedData* encryptedData)
+{
+ if (encryptedData->getDOM()==NULL)
+ throw DecryptionException("The object must be marshalled before decryption.");
+
+ // We can reuse the cipher object if the document hasn't changed.
+
+ if (m_cipher && m_cipher->getDocument()!=encryptedData->getDOM()->getOwnerDocument()) {
+ XMLToolingInternalConfig::getInternalConfig().m_xsecProvider->releaseCipher(m_cipher);
+ m_cipher=NULL;
+ }
+
+ if (!m_cipher)
+ m_cipher=XMLToolingInternalConfig::getInternalConfig().m_xsecProvider->newCipher(encryptedData->getDOM()->getOwnerDocument());
+
+ try {
+ // Resolve decryption key.
+ XSECCryptoKey* key=NULL;
+ if (m_resolver)
+ key=m_resolver->resolveKey(encryptedData->getKeyInfo());
+ if (!key) {
+ // See if there's an encrypted key present. We'll need the algorithm...
+ const XMLCh* algorithm=
+ encryptedData->getEncryptionMethod() ? encryptedData->getEncryptionMethod()->getAlgorithm() : NULL;
+ if (!algorithm)
+ throw DecryptionException("No EncryptionMethod/@Algorithm set, key decryption cannot proceed.");
+
+ if (encryptedData->getKeyInfo()) {
+ const vector<XMLObject*>& others=const_cast<const KeyInfo*>(encryptedData->getKeyInfo())->getOthers();
+ for (vector<XMLObject*>::const_iterator i=others.begin(); i!=others.end(); i++) {
+ EncryptedKey* encKey=dynamic_cast<EncryptedKey*>(*i);
+ if (encKey) {
+ try {
+ key=decryptKey(encKey, algorithm);
+ }
+ catch (DecryptionException& e) {
+ log4cpp::Category::getInstance(XMLTOOLING_LOGCAT".Decrypter").warn(e.what());
+ }
+ }
+ }
+ }
+
+ if (!key)
+ throw DecryptionException("Unable to resolve a decryption key.");
+ }
+
+ m_cipher->setKey(key);
+ DOMNode* ret=m_cipher->decryptElementDetached(encryptedData->getDOM());
+ if (ret->getNodeType()!=DOMNode::DOCUMENT_FRAGMENT_NODE) {
+ ret->release();
+ throw DecryptionException("Decryption operation did not result in DocumentFragment.");
+ }
+ return static_cast<DOMDocumentFragment*>(ret);
+ }
+ catch(XSECException& e) {
+ auto_ptr_char temp(e.getMsg());
+ throw DecryptionException(string("XMLSecurity exception while decrypting: ") + temp.get());
+ }
+ catch(XSECCryptoException& e) {
+ throw DecryptionException(string("XMLSecurity exception while decrypting: ") + e.getMsg());
+ }
+}
+
+XSECCryptoKey* Decrypter::decryptKey(EncryptedKey* encryptedKey, const XMLCh* algorithm)
+{
+ if (encryptedKey->getDOM()==NULL)
+ throw DecryptionException("The object must be marshalled before decryption.");
+
+ // We can reuse the cipher object if the document hasn't changed.
+
+ if (m_cipher && m_cipher->getDocument()!=encryptedKey->getDOM()->getOwnerDocument()) {
+ XMLToolingInternalConfig::getInternalConfig().m_xsecProvider->releaseCipher(m_cipher);
+ m_cipher=NULL;
+ }
+
+ if (!m_cipher)
+ m_cipher=XMLToolingInternalConfig::getInternalConfig().m_xsecProvider->newCipher(encryptedKey->getDOM()->getOwnerDocument());
+
+ try {
+ // Resolve key decryption key.
+ XSECCryptoKey* key=NULL;
+ if (m_KEKresolver)
+ key=m_KEKresolver->resolveKey(encryptedKey->getKeyInfo());
+ if (!key)
+ throw DecryptionException("Unable to resolve a key decryption key.");
+ m_cipher->setKEK(key);
+
+ XMLByte buffer[1024];
+ int keySize = m_cipher->decryptKey(encryptedKey->getDOM(), buffer, 1024);
+ if (keySize > 0) {
+ // Try to map the key.
+ XSECAlgorithmHandler* handler = XSECPlatformUtils::g_algorithmMapper->mapURIToHandler(algorithm);
+ if (handler != NULL)
+ return handler->createKeyForURI(algorithm, buffer, keySize);
+ throw DecryptionException("Unrecognized algorithm, could not build object around decrypted key.");
+ }
+ throw DecryptionException("Unable to decrypt key.");
+ }
+ catch(XSECException& e) {
+ auto_ptr_char temp(e.getMsg());
+ throw DecryptionException(string("XMLSecurity exception while decrypting: ") + temp.get());
+ }
+ catch(XSECCryptoException& e) {
+ throw DecryptionException(string("XMLSecurity exception while decrypting: ") + e.getMsg());
+ }
+}
projects / shibboleth / cpp-xmltooling.git / commitdiff