2 * Copyright 2001-2006 Internet2
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
18 * SimpleSigningRule.cpp
20 * Blob-oriented signature checking SecurityPolicyRule
24 #include "exceptions.h"
25 #include "binding/HTTPRequest.h"
26 #include "binding/SimpleSigningRule.h"
27 #include "saml2/core/Protocols.h"
28 #include "saml2/metadata/Metadata.h"
29 #include "saml2/metadata/MetadataProvider.h"
31 #include <log4cpp/Category.hh>
32 #include <xmltooling/util/NDC.h>
33 #include <xmltooling/util/ReplayCache.h>
34 #include <xsec/enc/XSECCryptoException.hpp>
35 #include <xsec/enc/XSECCryptoProvider.hpp>
36 #include <xsec/framework/XSECException.hpp>
38 using namespace opensaml::saml2md;
39 using namespace opensaml;
40 using namespace xmltooling;
41 using namespace log4cpp;
44 using xmlsignature::KeyInfo;
47 SecurityPolicyRule* SAML_DLLLOCAL SimpleSigningRuleFactory(const DOMElement* const & e)
49 return new SimpleSigningRule(e);
52 // Appends a raw parameter=value pair to the string.
53 static bool appendParameter(string& s, const char* data, const char* name)
55 const char* start = strstr(data,name);
60 const char* end = strchr(start,'&');
62 s.append(start, end-start);
70 pair<saml2::Issuer*,const RoleDescriptor*> SimpleSigningRule::evaluate(
71 const XMLObject& message,
72 const GenericRequest* request,
73 const MetadataProvider* metadataProvider,
75 const TrustEngine* trustEngine
78 Category& log=Category::getInstance(SAML_LOGCAT".SecurityPolicyRule.SimpleSigning");
79 log.debug("evaluating simple signing policy");
81 pair<saml2::Issuer*,const RoleDescriptor*> ret = pair<saml2::Issuer*,const RoleDescriptor*>(NULL,NULL);
83 const HTTPRequest* httpRequest = dynamic_cast<const HTTPRequest*>(request);
84 if (!request || !httpRequest) {
85 log.debug("ignoring message, no HTTP protocol request available");
89 if (!metadataProvider || !role || !trustEngine) {
90 log.debug("ignoring message, no metadata supplied");
94 const char* signature = request->getParameter("Signature");
96 log.debug("ignoring unsigned message");
100 const char* sigAlgorithm = request->getParameter("SigAlg");
102 log.error("SigAlg parameter not found, no way to verify the signature");
107 log.debug("extracting issuer from message");
108 pair<saml2::Issuer*,const XMLCh*> issuerInfo = getIssuerAndProtocol(message);
110 auto_ptr<saml2::Issuer> issuer(issuerInfo.first);
111 if (!issuerInfo.first || !issuerInfo.second ||
112 (issuer->getFormat() && !XMLString::equals(issuer->getFormat(), saml2::NameIDType::ENTITY))) {
113 log.warn("issuer identity not estabished, or was not an entityID");
117 log.debug("searching metadata for message issuer...");
118 const EntityDescriptor* entity = metadataProvider->getEntityDescriptor(issuer->getName());
120 auto_ptr_char temp(issuer->getName());
121 log.warn("no metadata found, can't establish identity of issuer (%s)", temp.get());
125 log.debug("matched message issuer against metadata, searching for applicable role...");
126 const RoleDescriptor* roledesc=entity->getRoleDescriptor(*role, issuerInfo.second);
128 log.warn("unable to find compatible role (%s) in metadata", role->toString().c_str());
134 if (!strcmp(httpRequest->getMethod(), "GET")) {
135 // We have to construct a string containing the signature input by accessing the
136 // request directly. We can't use the decoded parameters because we need the raw
137 // data and URL-encoding isn't canonical.
138 pch = httpRequest->getQueryString();
139 if (!appendParameter(input, pch, "SAMLRequest="))
140 appendParameter(input, pch, "SAMLResponse=");
141 appendParameter(input, pch, "RelayState=");
142 appendParameter(input, pch, "SigAlg=");
145 // With POST, the input string is concatenated from the decoded form controls.
146 // GET should be this way too, but I messed up the spec, sorry.
147 pch = httpRequest->getParameter("SAMLRequest");
149 input = string("SAMLRequest=") + pch;
151 pch = httpRequest->getParameter("SAMLResponse");
152 input = string("SAMLResponse=") + pch;
154 pch = httpRequest->getParameter("RelayState");
156 input = input + "&RelayState=" + pch;
157 input = input + "&SigAlg=" + sigAlgorithm;
160 // Check for KeyInfo, but defensively (we might be able to run without it).
161 KeyInfo* keyInfo=NULL;
162 pch = request->getParameter("KeyInfo");
165 istringstream kstrm(pch);
166 DOMDocument* doc = XMLToolingConfig::getConfig().getParser().parse(kstrm);
167 XercesJanitor<DOMDocument> janitor(doc);
168 XMLObject* kxml = XMLObjectBuilder::buildOneFromElement(doc->getDocumentElement(), true);
170 if (!(keyInfo=dynamic_cast<KeyInfo*>(kxml)))
173 catch (XMLToolingException& ex) {
174 log.warn("Failed to load KeyInfo from message: %s", ex.what());
178 auto_ptr<KeyInfo> kjanitor(keyInfo);
179 auto_ptr_XMLCh alg(sigAlgorithm);
181 if (!trustEngine->validate(alg.get(), signature, keyInfo, input.c_str(), input.length(), *roledesc, metadataProvider->getKeyResolver())) {
182 log.error("unable to verify signature on message with supplied trust engine");
186 if (log.isDebugEnabled()) {
187 auto_ptr_char iname(entity->getEntityID());
188 log.debug("message from (%s), signature verified", iname.get());
191 ret.first = issuer.release();
192 ret.second = roledesc;
196 log.warn("caught a bad_cast while extracting issuer");
201 pair<saml2::Issuer*,const XMLCh*> SimpleSigningRule::getIssuerAndProtocol(const XMLObject& message) const
203 // We just let any bad casts throw here.
205 // Shortcuts some of the casting.
206 const XMLCh* ns = message.getElementQName().getNamespaceURI();
208 if (XMLString::equals(ns, samlconstants::SAML20P_NS)) {
209 // 2.0 namespace should be castable to a specialized 2.0 root.
210 const saml2::RootObject& root = dynamic_cast<const saml2::RootObject&>(message);
211 saml2::Issuer* issuer = root.getIssuer();
212 if (issuer && issuer->getName())
213 return make_pair(issuer->cloneIssuer(), samlconstants::SAML20P_NS);
215 // No issuer in the message, so we have to try the Response approach.
216 const vector<saml2::Assertion*>& assertions = dynamic_cast<const saml2p::Response&>(message).getAssertions();
217 if (!assertions.empty()) {
218 issuer = assertions.front()->getIssuer();
219 if (issuer && issuer->getName())
220 return make_pair(issuer->cloneIssuer(), samlconstants::SAML20P_NS);
224 return pair<saml2::Issuer*,const XMLCh*>(NULL,NULL);