shibsp/handler/impl/SAML2LogoutInitiator.cpp

   1 /**
   2  * Licensed to the University Corporation for Advanced Internet
   3  * Development, Inc. (UCAID) under one or more contributor license
   4  * agreements. See the NOTICE file distributed with this work for
   5  * additional information regarding copyright ownership.
   6  *
   7  * UCAID licenses this file to you under the Apache License,
   8  * Version 2.0 (the "License"); you may not use this file except
   9  * in compliance with the License. You may obtain a copy of the
  10  * License at
  11  *
  12  * http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  * Unless required by applicable law or agreed to in writing,
  15  * software distributed under the License is distributed on an
  16  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
  17  * either express or implied. See the License for the specific
  18  * language governing permissions and limitations under the License.
  19  */
  20
  21 /**
  22  * SAML2LogoutInitiator.cpp
  23  *
  24  * Triggers SP-initiated logout for SAML 2.0 sessions.
  25  */
  26
  27 #include "internal.h"
  28 #include "exceptions.h"
  29 #include "Application.h"
  30 #include "ServiceProvider.h"
  31 #include "SessionCache.h"
  32 #include "handler/AbstractHandler.h"
  33 #include "handler/LogoutInitiator.h"
  34
  35 #ifndef SHIBSP_LITE
  36 # include "binding/SOAPClient.h"
  37 # include "metadata/MetadataProviderCriteria.h"
  38 # include "security/SecurityPolicy.h"
  39 # include <boost/algorithm/string.hpp>
  40 # include <boost/iterator/indirect_iterator.hpp>
  41 # include <saml/exceptions.h>
  42 # include <saml/SAMLConfig.h>
  43 # include <saml/saml2/core/Protocols.h>
  44 # include <saml/saml2/binding/SAML2SOAPClient.h>
  45 # include <saml/saml2/metadata/EndpointManager.h>
  46 # include <saml/saml2/metadata/Metadata.h>
  47 # include <saml/saml2/metadata/MetadataCredentialCriteria.h>
  48 using namespace opensaml::saml2;
  49 using namespace opensaml::saml2p;
  50 using namespace opensaml::saml2md;
  51 using namespace opensaml;
  52 #else
  53 # include "lite/SAMLConstants.h"
  54 #endif
  55
  56 using namespace shibsp;
  57 using namespace xmltooling;
  58 using namespace boost;
  59 using namespace std;
  60
  61 namespace shibsp {
  62
  63 #if defined (_MSC_VER)
  64     #pragma warning( push )
  65     #pragma warning( disable : 4250 )
  66 #endif
  67
  68     class SHIBSP_DLLLOCAL SAML2LogoutInitiator : public AbstractHandler, public LogoutInitiator
  69     {
  70     public:
  71         SAML2LogoutInitiator(const DOMElement* e, const char* appId);
  72         virtual ~SAML2LogoutInitiator() {}
  73
  74         void init(const char* location);    // encapsulates actions that need to run either in the c'tor or setParent
  75
  76         void setParent(const PropertySet* parent);
  77         void receive(DDF& in, ostream& out);
  78         pair<bool,long> run(SPRequest& request, bool isHandler=true) const;
  79
  80         const XMLCh* getProtocolFamily() const {
  81             return samlconstants::SAML20P_NS;
  82         }
  83
  84     private:
  85         pair<bool,long> doRequest(
  86             const Application& application, const HTTPRequest& request, HTTPResponse& httpResponse, Session* session
  87             ) const;
  88
  89         string m_appId;
  90         auto_ptr_char m_protocol;
  91 #ifndef SHIBSP_LITE
  92         auto_ptr<LogoutRequest> buildRequest(
  93             const Application& application, const Session& session, const RoleDescriptor& role, const MessageEncoder* encoder=nullptr
  94             ) const;
  95
  96         LogoutEvent* newLogoutEvent(
  97             const Application& application, const HTTPRequest* request=nullptr, const Session* session=nullptr
  98             ) const {
  99             LogoutEvent* e = LogoutHandler::newLogoutEvent(application, request, session);
 100             if (e)
 101                 e->m_protocol = m_protocol.get();
 102             return e;
 103         }
 104
 105         bool m_async;
 106         vector<string> m_bindings;
 107         map< string,boost::shared_ptr<MessageEncoder> > m_encoders;
 108 #endif
 109     };
 110
 111 #if defined (_MSC_VER)
 112     #pragma warning( pop )
 113 #endif
 114
 115     Handler* SHIBSP_DLLLOCAL SAML2LogoutInitiatorFactory(const pair<const DOMElement*,const char*>& p)
 116     {
 117         return new SAML2LogoutInitiator(p.first, p.second);
 118     }
 119 };
 120
 121 SAML2LogoutInitiator::SAML2LogoutInitiator(const DOMElement* e, const char* appId)
 122     : AbstractHandler(e, Category::getInstance(SHIBSP_LOGCAT ".LogoutInitiator.SAML2")), m_appId(appId), m_protocol(samlconstants::SAML20P_NS)
 123 #ifndef SHIBSP_LITE
 124         ,m_async(true)
 125 #endif
 126 {
 127     // If Location isn't set, defer initialization until the setParent call.
 128     pair<bool,const char*> loc = getString("Location");
 129     if (loc.first) {
 130         init(loc.second);
 131     }
 132 }
 133
 134 void SAML2LogoutInitiator::setParent(const PropertySet* parent)
 135 {
 136     DOMPropertySet::setParent(parent);
 137     pair<bool,const char*> loc = getString("Location");
 138     init(loc.second);
 139 }
 140
 141 void SAML2LogoutInitiator::init(const char* location)
 142 {
 143     if (location) {
 144         string address = m_appId + location + "::run::SAML2LI";
 145         setAddress(address.c_str());
 146     }
 147     else {
 148         m_log.warn("no Location property in SAML2 LogoutInitiator (or parent), can't register as remoted handler");
 149     }
 150
 151 #ifndef SHIBSP_LITE
 152     if (SPConfig::getConfig().isEnabled(SPConfig::OutOfProcess)) {
 153         pair<bool,bool> async = getBool("asynchronous");
 154         m_async = !async.first || async.second;
 155
 156         string dupBindings;
 157         pair<bool,const char*> outgoing = getString("outgoingBindings");
 158         if (outgoing.first) {
 159             dupBindings = outgoing.second;
 160             trim(dupBindings);
 161         }
 162         else {
 163             // No override, so we'll install a default binding precedence.
 164             dupBindings = string(samlconstants::SAML20_BINDING_HTTP_REDIRECT) + ' ' + samlconstants::SAML20_BINDING_HTTP_POST + ' ' +
 165                 samlconstants::SAML20_BINDING_HTTP_POST_SIMPLESIGN + ' ' + samlconstants::SAML20_BINDING_HTTP_ARTIFACT;
 166         }
 167         split(m_bindings, dupBindings, is_space(), algorithm::token_compress_on);
 168         for (vector<string>::const_iterator b = m_bindings.begin(); b != m_bindings.end(); ++b) {
 169             try {
 170                 boost::shared_ptr<MessageEncoder> encoder(
 171                     SAMLConfig::getConfig().MessageEncoderManager.newPlugin(*b, pair<const DOMElement*,const XMLCh*>(getElement(),nullptr))
 172                     );
 173                 if (encoder->isUserAgentPresent() && XMLString::equals(getProtocolFamily(), encoder->getProtocolFamily())) {
 174                     m_encoders[*b] = encoder;
 175                     m_log.debug("supporting outgoing binding (%s)", b->c_str());
 176                 }
 177                 else {
 178                     m_log.warn("skipping outgoing binding (%s), not a SAML 2.0 front-channel mechanism", b->c_str());
 179                 }
 180             }
 181             catch (std::exception& ex) {
 182                 m_log.error("error building MessageEncoder: %s", ex.what());
 183             }
 184         }
 185     }
 186 #endif
 187 }
 188
 189
 190 pair<bool,long> SAML2LogoutInitiator::run(SPRequest& request, bool isHandler) const
 191 {
 192     // Defer to base class for front-channel loop first.
 193     pair<bool,long> ret = LogoutHandler::run(request, isHandler);
 194     if (ret.first)
 195         return ret;
 196
 197     // At this point we know the front-channel is handled.
 198     // We need the session to do any other work.
 199
 200     Session* session = nullptr;
 201     try {
 202         session = request.getSession(false, true, false);  // don't cache it and ignore all checks
 203         if (!session)
 204             return make_pair(false, 0L);
 205
 206         // We only handle SAML 2.0 sessions.
 207         if (!XMLString::equals(session->getProtocol(), m_protocol.get())) {
 208             session->unlock();
 209             return make_pair(false, 0L);
 210         }
 211     }
 212     catch (std::exception& ex) {
 213         m_log.error("error accessing current session: %s", ex.what());
 214         return make_pair(false, 0L);
 215     }
 216
 217     if (SPConfig::getConfig().isEnabled(SPConfig::OutOfProcess)) {
 218         // When out of process, we run natively.
 219         return doRequest(request.getApplication(), request, request, session);
 220     }
 221     else {
 222         // When not out of process, we remote the request.
 223         session->unlock();
 224         vector<string> headers(1,"Cookie");
 225         DDF out,in = wrap(request,&headers);
 226         DDFJanitor jin(in), jout(out);
 227         out=request.getServiceProvider().getListenerService()->send(in);
 228         return unwrap(request, out);
 229     }
 230 }
 231
 232 void SAML2LogoutInitiator::receive(DDF& in, ostream& out)
 233 {
 234 #ifndef SHIBSP_LITE
 235     // Defer to base class for notifications
 236     if (in["notify"].integer() == 1)
 237         return LogoutHandler::receive(in, out);
 238
 239     // Find application.
 240     const char* aid=in["application_id"].string();
 241     const Application* app=aid ? SPConfig::getConfig().getServiceProvider()->getApplication(aid) : nullptr;
 242     if (!app) {
 243         // Something's horribly wrong.
 244         m_log.error("couldn't find application (%s) for logout", aid ? aid : "(missing)");
 245         throw ConfigurationException("Unable to locate application for logout, deleted?");
 246     }
 247
 248     // Unpack the request.
 249     scoped_ptr<HTTPRequest> req(getRequest(in));
 250
 251     // Set up a response shim.
 252     DDF ret(nullptr);
 253     DDFJanitor jout(ret);
 254     scoped_ptr<HTTPResponse> resp(getResponse(ret));
 255
 256     Session* session = nullptr;
 257     try {
 258          session = app->getServiceProvider().getSessionCache()->find(*app, *req, nullptr, nullptr);
 259     }
 260     catch (std::exception& ex) {
 261         m_log.error("error accessing current session: %s", ex.what());
 262     }
 263
 264     // With no session, we just skip the request and let it fall through to an empty struct return.
 265     if (session) {
 266         if (session->getNameID() && session->getEntityID()) {
 267             // Since we're remoted, the result should either be a throw, which we pass on,
 268             // a false/0 return, which we just return as an empty structure, or a response/redirect,
 269             // which we capture in the facade and send back.
 270             doRequest(*app, *req, *resp, session);
 271         }
 272         else {
 273             session->unlock();
 274             m_log.log(getParent() ? Priority::WARN : Priority::ERROR, "bypassing SAML 2.0 logout, no NameID or issuing entityID found in session");
 275             app->getServiceProvider().getSessionCache()->remove(*app, *req, resp.get());
 276         }
 277     }
 278     out << ret;
 279 #else
 280     throw ConfigurationException("Cannot perform logout using lite version of shibsp library.");
 281 #endif
 282 }
 283
 284 pair<bool,long> SAML2LogoutInitiator::doRequest(
 285     const Application& application, const HTTPRequest& httpRequest, HTTPResponse& httpResponse, Session* session
 286     ) const
 287 {
 288     Locker sessionLocker(session, false);
 289 #ifndef SHIBSP_LITE
 290     scoped_ptr<LogoutEvent> logout_event(newLogoutEvent(application, &httpRequest, session));
 291 #endif
 292
 293     // Do back channel notification.
 294     vector<string> sessions(1, session->getID());
 295     if (!notifyBackChannel(application, httpRequest.getRequestURL(), sessions, false)) {
 296 #ifndef SHIBSP_LITE
 297         if (logout_event) {
 298             logout_event->m_logoutType = LogoutEvent::LOGOUT_EVENT_PARTIAL;
 299             application.getServiceProvider().getTransactionLog()->write(*logout_event);
 300         }
 301 #endif
 302         sessionLocker.assign();
 303         session = nullptr;
 304         application.getServiceProvider().getSessionCache()->remove(application, httpRequest, &httpResponse);
 305         return sendLogoutPage(application, httpRequest, httpResponse, "partial");
 306     }
 307
 308 #ifndef SHIBSP_LITE
 309     pair<bool,long> ret = make_pair(false, 0L);
 310     try {
 311         // With a session in hand, we can create a LogoutRequest message, if we can find a compatible endpoint.
 312         MetadataProvider* m = application.getMetadataProvider();
 313         Locker metadataLocker(m);
 314         MetadataProviderCriteria mc(application, session->getEntityID(), &IDPSSODescriptor::ELEMENT_QNAME, samlconstants::SAML20P_NS);
 315         pair<const EntityDescriptor*,const RoleDescriptor*> entity = m->getEntityDescriptor(mc);
 316         if (!entity.first) {
 317             throw MetadataException(
 318                 "Unable to locate metadata for identity provider ($entityID)", namedparams(1, "entityID", session->getEntityID())
 319                 );
 320         }
 321         else if (!entity.second) {
 322             throw MetadataException(
 323                 "Unable to locate SAML 2.0 IdP role for identity provider ($entityID).", namedparams(1, "entityID", session->getEntityID())
 324                 );
 325         }
 326
 327         const IDPSSODescriptor* role = dynamic_cast<const IDPSSODescriptor*>(entity.second);
 328         if (role->getSingleLogoutServices().empty()) {
 329             throw MetadataException(
 330                 "No SingleLogoutService endpoints in metadata for identity provider ($entityID).", namedparams(1, "entityID", session->getEntityID())
 331                 );
 332         }
 333
 334         const EndpointType* ep = nullptr;
 335         const MessageEncoder* encoder = nullptr;
 336         for (vector<string>::const_iterator b = m_bindings.begin(); b != m_bindings.end(); ++b) {
 337             auto_ptr_XMLCh wideb(b->c_str());
 338             ep = EndpointManager<SingleLogoutService>(role->getSingleLogoutServices()).getByBinding(wideb.get());
 339             if (ep) {
 340                 map< string,boost::shared_ptr<MessageEncoder> >::const_iterator enc = m_encoders.find(*b);
 341                 if (enc != m_encoders.end())
 342                     encoder = enc->second.get();
 343                 break;
 344             }
 345         }
 346         if (!ep || !encoder) {
 347             m_log.debug("no compatible front channel SingleLogoutService, trying back channel...");
 348             shibsp::SecurityPolicy policy(application);
 349             shibsp::SOAPClient soaper(policy);
 350             MetadataCredentialCriteria mcc(*role);
 351
 352             LogoutResponse* logoutResponse = nullptr;
 353             scoped_ptr<StatusResponseType> srt;
 354             auto_ptr_XMLCh binding(samlconstants::SAML20_BINDING_SOAP);
 355             const vector<SingleLogoutService*>& endpoints = role->getSingleLogoutServices();
 356             for (indirect_iterator<vector<SingleLogoutService*>::const_iterator> epit = make_indirect_iterator(endpoints.begin());
 357                     !logoutResponse && epit != make_indirect_iterator(endpoints.end()); ++epit) {
 358                 try {
 359                     if (!XMLString::equals(epit->getBinding(), binding.get()))
 360                         continue;
 361                     auto_ptr<LogoutRequest> msg(buildRequest(application, *session, *role));
 362
 363                     // Log the request.
 364                     if (logout_event) {
 365                         logout_event->m_logoutType = LogoutEvent::LOGOUT_EVENT_UNKNOWN;
 366                         logout_event->m_saml2Request = msg.get();
 367                         application.getServiceProvider().getTransactionLog()->write(*logout_event);
 368                         logout_event->m_saml2Request = nullptr;
 369                     }
 370
 371                     auto_ptr_char dest(epit->getLocation());
 372                     SAML2SOAPClient client(soaper, false);
 373                     client.sendSAML(msg.release(), application.getId(), mcc, dest.get());
 374                     srt.reset(client.receiveSAML());
 375                     if (!(logoutResponse = dynamic_cast<LogoutResponse*>(srt.get()))) {
 376                         break;
 377                     }
 378                 }
 379                 catch (std::exception& ex) {
 380                     m_log.error("error sending LogoutRequest message: %s", ex.what());
 381                     soaper.reset();
 382                 }
 383             }
 384
 385             // No answer at all?
 386             if (!logoutResponse) {
 387                 if (endpoints.empty())
 388                     m_log.info("IdP doesn't support single logout protocol over a compatible binding");
 389                 else
 390                     m_log.warn("IdP didn't respond to logout request");
 391
 392                 // Log the end result.
 393                 if (logout_event) {
 394                     logout_event->m_logoutType = LogoutEvent::LOGOUT_EVENT_PARTIAL;
 395                     application.getServiceProvider().getTransactionLog()->write(*logout_event);
 396                 }
 397
 398                 ret = sendLogoutPage(application, httpRequest, httpResponse, "partial");
 399             }
 400             else {
 401                 // Check the status, looking for non-success or a partial logout code.
 402                 const StatusCode* sc = logoutResponse->getStatus() ? logoutResponse->getStatus()->getStatusCode() : nullptr;
 403                 bool partial = (!sc || !XMLString::equals(sc->getValue(), StatusCode::SUCCESS));
 404                 if (!partial && sc->getStatusCode()) {
 405                     // Success, but still need to check for partial.
 406                     partial = XMLString::equals(sc->getStatusCode()->getValue(), StatusCode::PARTIAL_LOGOUT);
 407                 }
 408
 409                 // Log the end result.
 410                 if (logout_event) {
 411                     logout_event->m_logoutType = partial ? LogoutEvent::LOGOUT_EVENT_PARTIAL : LogoutEvent::LOGOUT_EVENT_GLOBAL;
 412                     logout_event->m_saml2Response = logoutResponse;
 413                     application.getServiceProvider().getTransactionLog()->write(*logout_event);
 414                 }
 415
 416                 if (partial)
 417                     ret = sendLogoutPage(application, httpRequest, httpResponse, "partial");
 418                 else {
 419                     const char* returnloc = httpRequest.getParameter("return");
 420                     if (returnloc) {
 421                         // Relative URLs get promoted, absolutes get validated.
 422                         if (*returnloc == '/') {
 423                             string loc(returnloc);
 424                             httpRequest.absolutize(loc);
 425                             ret.second = httpResponse.sendRedirect(loc.c_str());
 426                         }
 427                         else {
 428                             application.limitRedirect(httpRequest, returnloc);
 429                             ret.second = httpResponse.sendRedirect(returnloc);
 430                         }
 431                         ret.first = true;
 432                     }
 433                     else {
 434                         ret = sendLogoutPage(application, httpRequest, httpResponse, "global");
 435                     }
 436                 }
 437             }
 438
 439             if (session) {
 440                 sessionLocker.assign();
 441                 session = nullptr;
 442                 application.getServiceProvider().getSessionCache()->remove(application, httpRequest, &httpResponse);
 443             }
 444
 445             return ret;
 446         }
 447
 448         // Save off return location as RelayState.
 449         string relayState;
 450         const char* returnloc = httpRequest.getParameter("return");
 451         if (returnloc) {
 452             application.limitRedirect(httpRequest, returnloc);
 453             relayState = returnloc;
 454             httpRequest.absolutize(relayState);
 455             cleanRelayState(application, httpRequest, httpResponse);
 456             preserveRelayState(application, httpResponse, relayState);
 457         }
 458
 459         auto_ptr<LogoutRequest> msg(buildRequest(application, *session, *role, encoder));
 460         msg->setDestination(ep->getLocation());
 461
 462         // Log the request.
 463         if (logout_event) {
 464             logout_event->m_logoutType = LogoutEvent::LOGOUT_EVENT_UNKNOWN;
 465             logout_event->m_saml2Request = msg.get();
 466             application.getServiceProvider().getTransactionLog()->write(*logout_event);
 467         }
 468
 469         auto_ptr_char dest(ep->getLocation());
 470         ret.second = sendMessage(*encoder, msg.get(), relayState.c_str(), dest.get(), role, application, httpResponse, true);
 471         ret.first = true;
 472         msg.release();  // freed by encoder
 473
 474         if (session) {
 475             sessionLocker.assign();
 476             session = nullptr;
 477             application.getServiceProvider().getSessionCache()->remove(application, httpRequest, &httpResponse);
 478         }
 479     }
 480     catch (MetadataException& mex) {
 481         // Less noise for IdPs that don't support logout (i.e. most)
 482         m_log.info("unable to issue SAML 2.0 logout request: %s", mex.what());
 483     }
 484     catch (std::exception& ex) {
 485         m_log.error("error issuing SAML 2.0 logout request: %s", ex.what());
 486     }
 487
 488     return ret;
 489 #else
 490     throw ConfigurationException("Cannot perform logout using lite version of shibsp library.");
 491 #endif
 492 }
 493
 494 #ifndef SHIBSP_LITE
 495
 496 auto_ptr<LogoutRequest> SAML2LogoutInitiator::buildRequest(
 497     const Application& application, const Session& session, const RoleDescriptor& role, const MessageEncoder* encoder
 498     ) const
 499 {
 500     const PropertySet* relyingParty = application.getRelyingParty(dynamic_cast<EntityDescriptor*>(role.getParent()));
 501
 502     auto_ptr<LogoutRequest> msg(LogoutRequestBuilder::buildLogoutRequest());
 503     Issuer* issuer = IssuerBuilder::buildIssuer();
 504     msg->setIssuer(issuer);
 505     issuer->setName(relyingParty->getXMLString("entityID").second);
 506     auto_ptr_XMLCh index(session.getSessionIndex());
 507     if (index.get() && *index.get()) {
 508         SessionIndex* si = SessionIndexBuilder::buildSessionIndex();
 509         msg->getSessionIndexs().push_back(si);
 510         si->setSessionIndex(index.get());
 511     }
 512
 513     const NameID* nameid = session.getNameID();
 514     pair<bool,const char*> flag = relyingParty->getString("encryption");
 515     if (flag.first &&
 516         (!strcmp(flag.second, "true") || (encoder && !strcmp(flag.second, "front")) || (!encoder && !strcmp(flag.second, "back")))) {
 517         auto_ptr<EncryptedID> encrypted(EncryptedIDBuilder::buildEncryptedID());
 518         MetadataCredentialCriteria mcc(role);
 519         encrypted->encrypt(
 520             *nameid,
 521             *(application.getMetadataProvider()),
 522             mcc,
 523             encoder ? encoder->isCompact() : false,
 524             relyingParty->getXMLString("encryptionAlg").second
 525             );
 526         msg->setEncryptedID(encrypted.get());
 527         encrypted.release();
 528     }
 529     else {
 530         msg->setNameID(nameid->cloneNameID());
 531     }
 532
 533     XMLCh* msgid = SAMLConfig::getConfig().generateIdentifier();
 534     msg->setID(msgid);
 535     XMLString::release(&msgid);
 536     msg->setIssueInstant(time(nullptr));
 537
 538     if (m_async && encoder) {
 539         msg->setExtensions(saml2p::ExtensionsBuilder::buildExtensions());
 540         msg->getExtensions()->getUnknownXMLObjects().push_back(AsynchronousBuilder::buildAsynchronous());
 541     }
 542
 543     return msg;
 544 }
 545
 546 #endif