2 * Copyright 2001-2010 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/SecurityPolicy.h"
26 #include "binding/SecurityPolicyRule.h"
27 #include "saml2/core/Assertions.h"
28 #include "saml2/metadata/Metadata.h"
29 #include "saml2/metadata/MetadataCredentialCriteria.h"
30 #include "saml2/metadata/MetadataProvider.h"
32 #include <xercesc/util/Base64.hpp>
33 #include <xmltooling/logging.h>
34 #include <xmltooling/XMLToolingConfig.h>
35 #include <xmltooling/io/HTTPRequest.h>
36 #include <xmltooling/security/SignatureTrustEngine.h>
37 #include <xmltooling/signature/KeyInfo.h>
38 #include <xmltooling/signature/Signature.h>
39 #include <xmltooling/util/ParserPool.h>
41 using namespace opensaml::saml2md;
42 using namespace opensaml;
43 using namespace xmltooling::logging;
44 using namespace xmltooling;
47 using xmlsignature::KeyInfo;
48 using xmlsignature::SignatureException;
51 class SAML_DLLLOCAL SimpleSigningRule : public SecurityPolicyRule
54 SimpleSigningRule(const DOMElement* e);
55 virtual ~SimpleSigningRule() {}
57 const char* getType() const {
58 return SIMPLESIGNING_POLICY_RULE;
60 bool evaluate(const XMLObject& message, const GenericRequest* request, SecurityPolicy& policy) const;
63 // Appends a raw parameter=value pair to the string.
64 static bool appendParameter(string& s, const char* data, const char* name);
69 SecurityPolicyRule* SAML_DLLLOCAL SimpleSigningRuleFactory(const DOMElement* const & e)
71 return new SimpleSigningRule(e);
74 static const XMLCh errorFatal[] = UNICODE_LITERAL_10(e,r,r,o,r,F,a,t,a,l);
77 bool SimpleSigningRule::appendParameter(string& s, const char* data, const char* name)
79 const char* start = strstr(data,name);
84 const char* end = strchr(start,'&');
86 s.append(start, end-start);
92 SimpleSigningRule::SimpleSigningRule(const DOMElement* e) : m_errorFatal(false)
95 const XMLCh* flag = e->getAttributeNS(nullptr, errorFatal);
96 m_errorFatal = (flag && (*flag==chLatin_t || *flag==chDigit_1));
100 bool SimpleSigningRule::evaluate(const XMLObject& message, const GenericRequest* request, SecurityPolicy& policy) const
102 Category& log=Category::getInstance(SAML_LOGCAT".SecurityPolicyRule.SimpleSigning");
104 if (!policy.getIssuerMetadata()) {
105 log.debug("ignoring message, no issuer metadata supplied");
109 const SignatureTrustEngine* sigtrust;
110 if (!(sigtrust=dynamic_cast<const SignatureTrustEngine*>(policy.getTrustEngine()))) {
111 log.debug("ignoring message, no SignatureTrustEngine supplied");
115 const HTTPRequest* httpRequest = dynamic_cast<const HTTPRequest*>(request);
116 if (!request || !httpRequest)
119 const char* signature = request->getParameter("Signature");
123 const char* sigAlgorithm = request->getParameter("SigAlg");
125 log.error("SigAlg parameter not found, no way to verify the signature");
131 if (!strcmp(httpRequest->getMethod(), "GET")) {
132 // We have to construct a string containing the signature input by accessing the
133 // request directly. We can't use the decoded parameters because we need the raw
134 // data and URL-encoding isn't canonical.
136 // NOTE: SimpleSign for GET means Redirect binding, which means we verify over the
137 // base64-encoded message directly.
139 pch = httpRequest->getQueryString();
140 if (!appendParameter(input, pch, "SAMLRequest="))
141 appendParameter(input, pch, "SAMLResponse=");
142 appendParameter(input, pch, "RelayState=");
143 appendParameter(input, pch, "SigAlg=");
146 // With POST, the input string is concatenated from the decoded form controls.
147 // GET should be this way too, but I messed up the spec, sorry.
149 // NOTE: SimpleSign for POST means POST binding, which means we verify over the
150 // base64-decoded XML. This sucks, because we have to decode the base64 directly.
151 // Serializing the XMLObject doesn't guarantee the signature will verify (this is
152 // why XMLSignature exists, and why this isn't really "simpler").
155 pch = httpRequest->getParameter("SAMLRequest");
157 XMLByte* decoded=Base64::decode(reinterpret_cast<const XMLByte*>(pch),&x);
159 log.warn("unable to decode base64 in POST binding message");
162 input = string("SAMLRequest=") + reinterpret_cast<const char*>(decoded);
163 #ifdef OPENSAML_XERCESC_HAS_XMLBYTE_RELEASE
164 XMLString::release(&decoded);
166 XMLString::release((char**)&decoded);
170 pch = httpRequest->getParameter("SAMLResponse");
171 XMLByte* decoded=Base64::decode(reinterpret_cast<const XMLByte*>(pch),&x);
173 log.warn("unable to decode base64 in POST binding message");
176 input = string("SAMLResponse=") + reinterpret_cast<const char*>(decoded);
177 #ifdef OPENSAML_XERCESC_HAS_XMLBYTE_RELEASE
178 XMLString::release(&decoded);
180 XMLString::release((char**)&decoded);
184 pch = httpRequest->getParameter("RelayState");
186 input = input + "&RelayState=" + pch;
187 input = input + "&SigAlg=" + sigAlgorithm;
190 // Check for KeyInfo, but defensively (we might be able to run without it).
191 KeyInfo* keyInfo=nullptr;
192 pch = request->getParameter("KeyInfo");
195 XMLByte* decoded=Base64::decode(reinterpret_cast<const XMLByte*>(pch),&x);
198 istringstream kstrm((char*)decoded);
199 DOMDocument* doc = XMLToolingConfig::getConfig().getParser().parse(kstrm);
200 XercesJanitor<DOMDocument> janitor(doc);
201 XMLObject* kxml = XMLObjectBuilder::buildOneFromElement(doc->getDocumentElement(), true);
203 if (!(keyInfo=dynamic_cast<KeyInfo*>(kxml)))
206 catch (XMLToolingException& ex) {
207 log.warn("Failed to load KeyInfo from message: %s", ex.what());
209 #ifdef OPENSAML_XERCESC_HAS_XMLBYTE_RELEASE
210 XMLString::release(&decoded);
212 XMLString::release((char**)&decoded);
216 log.warn("Failed to load KeyInfo from message: Unable to decode base64-encoded KeyInfo.");
220 auto_ptr<KeyInfo> kjanitor(keyInfo);
221 auto_ptr_XMLCh alg(sigAlgorithm);
223 // Set up criteria object.
224 MetadataCredentialCriteria cc(*(policy.getIssuerMetadata()));
225 cc.setXMLAlgorithm(alg.get());
227 if (!sigtrust->validate(alg.get(), signature, keyInfo, input.c_str(), input.length(), *(policy.getMetadataProvider()), &cc)) {
228 log.error("unable to verify message signature with supplied trust engine");
230 throw SecurityPolicyException("Message was signed, but signature could not be verified.");
234 log.debug("signature verified against message issuer");
235 policy.setAuthenticated(true);