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 GenericRequest& request,
72 const XMLObject& message,
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 if (!metadataProvider || !role || !trustEngine) {
84 log.debug("ignoring message, no metadata supplied");
88 const char* signature = request.getParameter("Signature");
90 log.debug("ignoring unsigned message");
94 const char* sigAlgorithm = request.getParameter("SigAlg");
96 log.error("SigAlg parameter not found, no way to verify the signature");
101 log.debug("extracting issuer from message");
102 pair<saml2::Issuer*,const XMLCh*> issuerInfo = getIssuerAndProtocol(message);
104 auto_ptr<saml2::Issuer> issuer(issuerInfo.first);
105 if (!issuerInfo.first || !issuerInfo.second ||
106 (issuer->getFormat() && !XMLString::equals(issuer->getFormat(), saml2::NameIDType::ENTITY))) {
107 log.warn("issuer identity not estabished, or was not an entityID");
111 log.debug("searching metadata for message issuer...");
112 const EntityDescriptor* entity = metadataProvider->getEntityDescriptor(issuer->getName());
114 auto_ptr_char temp(issuer->getName());
115 log.warn("no metadata found, can't establish identity of issuer (%s)", temp.get());
119 log.debug("matched message issuer against metadata, searching for applicable role...");
120 const RoleDescriptor* roledesc=entity->getRoleDescriptor(*role, issuerInfo.second);
122 log.warn("unable to find compatible role (%s) in metadata", role->toString().c_str());
128 const HTTPRequest& httpRequest = dynamic_cast<const HTTPRequest&>(request);
129 if (!strcmp(httpRequest.getMethod(), "GET")) {
130 // We have to construct a string containing the signature input by accessing the
131 // request directly. We can't use the decoded parameters because we need the raw
132 // data and URL-encoding isn't canonical.
133 pch = httpRequest.getQueryString();
134 if (!appendParameter(input, pch, "SAMLRequest="))
135 appendParameter(input, pch, "SAMLResponse=");
136 appendParameter(input, pch, "RelayState=");
137 appendParameter(input, pch, "SigAlg=");
140 // With POST, the input string is concatenated from the decoded form controls.
141 // GET should be this way too, but I messed up the spec, sorry.
142 pch = httpRequest.getParameter("SAMLRequest");
144 input = string("SAMLRequest=") + pch;
146 pch = httpRequest.getParameter("SAMLResponse");
147 input = string("SAMLResponse=") + pch;
149 pch = httpRequest.getParameter("RelayState");
151 input = input + "&RelayState=" + pch;
152 input = input + "&SigAlg=" + sigAlgorithm;
155 // Check for KeyInfo, but defensively (we might be able to run without it).
156 KeyInfo* keyInfo=NULL;
157 pch = request.getParameter("KeyInfo");
160 istringstream kstrm(pch);
161 DOMDocument* doc = XMLToolingConfig::getConfig().getParser().parse(kstrm);
162 XercesJanitor<DOMDocument> janitor(doc);
163 XMLObject* kxml = XMLObjectBuilder::buildOneFromElement(doc->getDocumentElement(), true);
165 if (!(keyInfo=dynamic_cast<KeyInfo*>(kxml)))
168 catch (XMLToolingException& ex) {
169 log.warn("Failed to load KeyInfo from message: %s", ex.what());
173 auto_ptr<KeyInfo> kjanitor(keyInfo);
174 auto_ptr_XMLCh alg(sigAlgorithm);
176 if (!trustEngine->validate(alg.get(), signature, keyInfo, input.c_str(), input.length(), *roledesc, metadataProvider->getKeyResolver())) {
177 log.error("unable to verify signature on message with supplied trust engine");
181 if (log.isDebugEnabled()) {
182 auto_ptr_char iname(entity->getEntityID());
183 log.debug("message from (%s), signature verified", iname.get());
186 ret.first = issuer.release();
187 ret.second = roledesc;
191 log.warn("caught a bad_cast while extracting issuer");
196 pair<saml2::Issuer*,const XMLCh*> SimpleSigningRule::getIssuerAndProtocol(const XMLObject& message) const
198 // We just let any bad casts throw here.
200 // Shortcuts some of the casting.
201 const XMLCh* ns = message.getElementQName().getNamespaceURI();
203 if (XMLString::equals(ns, samlconstants::SAML20P_NS)) {
204 // 2.0 namespace should be castable to a specialized 2.0 root.
205 const saml2::RootObject& root = dynamic_cast<const saml2::RootObject&>(message);
206 saml2::Issuer* issuer = root.getIssuer();
207 if (issuer && issuer->getName())
208 return make_pair(issuer->cloneIssuer(), samlconstants::SAML20P_NS);
210 // No issuer in the message, so we have to try the Response approach.
211 const vector<saml2::Assertion*>& assertions = dynamic_cast<const saml2p::Response&>(message).getAssertions();
212 if (!assertions.empty()) {
213 issuer = assertions.front()->getIssuer();
214 if (issuer && issuer->getName())
215 return make_pair(issuer->cloneIssuer(), samlconstants::SAML20P_NS);
219 return pair<saml2::Issuer*,const XMLCh*>(NULL,NULL);