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"
30 #include "security/TrustEngine.h"
32 #include <log4cpp/Category.hh>
33 #include <xmltooling/util/NDC.h>
34 #include <xmltooling/util/ReplayCache.h>
35 #include <xsec/enc/XSECCryptoException.hpp>
36 #include <xsec/enc/XSECCryptoProvider.hpp>
37 #include <xsec/framework/XSECException.hpp>
39 using namespace opensaml::saml2md;
40 using namespace opensaml;
41 using namespace xmltooling;
42 using namespace log4cpp;
45 using xmlsignature::KeyInfo;
48 SecurityPolicyRule* SAML_DLLLOCAL SimpleSigningRuleFactory(const DOMElement* const & e)
50 return new SimpleSigningRule(e);
53 // Appends a raw parameter=value pair to the string.
54 static bool appendParameter(string& s, const char* data, const char* name)
56 const char* start = strstr(data,name);
61 const char* end = strchr(start,'&');
63 s.append(start, end-start);
71 pair<saml2::Issuer*,const RoleDescriptor*> SimpleSigningRule::evaluate(
72 const GenericRequest& request,
73 const XMLObject& message,
74 const MetadataProvider* metadataProvider,
76 const opensaml::TrustEngine* trustEngine
79 Category& log=Category::getInstance(SAML_LOGCAT".SecurityPolicyRule.SimpleSigning");
80 log.debug("evaluating simple signing policy");
82 pair<saml2::Issuer*,const RoleDescriptor*> ret = pair<saml2::Issuer*,const RoleDescriptor*>(NULL,NULL);
84 if (!metadataProvider || !role || !trustEngine) {
85 log.debug("ignoring message, no metadata supplied");
89 const char* signature = request.getParameter("Signature");
91 log.debug("ignoring unsigned message");
95 const char* sigAlgorithm = request.getParameter("SigAlg");
97 log.error("SigAlg parameter not found, no way to verify the signature");
102 log.debug("extracting issuer from message");
103 pair<saml2::Issuer*,const XMLCh*> issuerInfo = getIssuerAndProtocol(message);
105 auto_ptr<saml2::Issuer> issuer(issuerInfo.first);
106 if (!issuerInfo.first || !issuerInfo.second ||
107 (issuer->getFormat() && !XMLString::equals(issuer->getFormat(), saml2::NameIDType::ENTITY))) {
108 log.warn("issuer identity not estabished, or was not an entityID");
112 log.debug("searching metadata for message issuer...");
113 const EntityDescriptor* entity = metadataProvider->getEntityDescriptor(issuer->getName());
115 auto_ptr_char temp(issuer->getName());
116 log.warn("no metadata found, can't establish identity of issuer (%s)", temp.get());
120 log.debug("matched message issuer against metadata, searching for applicable role...");
121 const RoleDescriptor* roledesc=entity->getRoleDescriptor(*role, issuerInfo.second);
123 log.warn("unable to find compatible role (%s) in metadata", role->toString().c_str());
129 const HTTPRequest& httpRequest = dynamic_cast<const HTTPRequest&>(request);
130 if (!strcmp(httpRequest.getMethod(), "GET")) {
131 // We have to construct a string containing the signature input by accessing the
132 // request directly. We can't use the decoded parameters because we need the raw
133 // data and URL-encoding isn't canonical.
134 pch = httpRequest.getQueryString();
135 if (!appendParameter(input, pch, "SAMLRequest="))
136 appendParameter(input, pch, "SAMLResponse=");
137 appendParameter(input, pch, "RelayState=");
138 appendParameter(input, pch, "SigAlg=");
141 // With POST, the input string is concatenated from the decoded form controls.
142 // GET should be this way too, but I messed up the spec, sorry.
143 pch = httpRequest.getParameter("SAMLRequest");
145 input = string("SAMLRequest=") + pch;
147 pch = httpRequest.getParameter("SAMLResponse");
148 input = string("SAMLResponse=") + pch;
150 pch = httpRequest.getParameter("RelayState");
152 input = input + "&RelayState=" + pch;
153 input = input + "&SigAlg=" + sigAlgorithm;
156 // Check for KeyInfo, but defensively (we might be able to run without it).
157 KeyInfo* keyInfo=NULL;
158 pch = request.getParameter("KeyInfo");
161 istringstream kstrm(pch);
162 DOMDocument* doc = XMLToolingConfig::getConfig().getParser().parse(kstrm);
163 XercesJanitor<DOMDocument> janitor(doc);
164 XMLObject* kxml = XMLObjectBuilder::buildOneFromElement(doc->getDocumentElement(), true);
166 if (!(keyInfo=dynamic_cast<KeyInfo*>(kxml)))
169 catch (XMLToolingException& ex) {
170 log.warn("Failed to load KeyInfo from message: %s", ex.what());
174 auto_ptr<KeyInfo> kjanitor(keyInfo);
175 auto_ptr_XMLCh alg(sigAlgorithm);
177 if (!trustEngine->validate(alg.get(), signature, keyInfo, input.c_str(), input.length(), *roledesc, metadataProvider->getKeyResolver())) {
178 log.error("unable to verify signature on message with supplied trust engine");
182 if (log.isDebugEnabled()) {
183 auto_ptr_char iname(entity->getEntityID());
184 log.debug("message from (%s), signature verified", iname.get());
187 ret.first = issuer.release();
188 ret.second = roledesc;
192 log.warn("caught a bad_cast while extracting issuer");
197 pair<saml2::Issuer*,const XMLCh*> SimpleSigningRule::getIssuerAndProtocol(const XMLObject& message) const
199 // We just let any bad casts throw here.
201 // Shortcuts some of the casting.
202 const XMLCh* ns = message.getElementQName().getNamespaceURI();
204 if (XMLString::equals(ns, samlconstants::SAML20P_NS)) {
205 // 2.0 namespace should be castable to a specialized 2.0 root.
206 const saml2::RootObject& root = dynamic_cast<const saml2::RootObject&>(message);
207 saml2::Issuer* issuer = root.getIssuer();
208 if (issuer && issuer->getName())
209 return make_pair(issuer->cloneIssuer(), samlconstants::SAML20P_NS);
211 // No issuer in the message, so we have to try the Response approach.
212 const vector<saml2::Assertion*>& assertions = dynamic_cast<const saml2p::Response&>(message).getAssertions();
213 if (!assertions.empty()) {
214 issuer = assertions.front()->getIssuer();
215 if (issuer && issuer->getName())
216 return make_pair(issuer->cloneIssuer(), samlconstants::SAML20P_NS);
220 return pair<saml2::Issuer*,const XMLCh*>(NULL,NULL);