+/*\r
+ * Copyright 2006 Internet2\r
+ * \r
+ * Licensed under the Apache License, Version 2.0 (the "License");\r
+ * you may not use this file except in compliance with the License.\r
+ * You may obtain a copy of the License at\r
+ *\r
+ * http://www.apache.org/licenses/LICENSE-2.0\r
+ *\r
+ * Unless required by applicable law or agreed to in writing, software\r
+ * distributed under the License is distributed on an "AS IS" BASIS,\r
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
+ * See the License for the specific language governing permissions and\r
+ * limitations under the License.\r
+ */\r
+\r
+/**\r
+ * AbstractPKIXTrustEngine.cpp\r
+ * \r
+ * A trust engine that uses X.509 trust anchors and CRLs associated with a role\r
+ * to perform PKIX validation of signatures and certificates.\r
+ */\r
+\r
+#include "internal.h"\r
+#include "security/AbstractPKIXTrustEngine.h"\r
+#include "signature/SignatureProfileValidator.h"\r
+\r
+#include <openssl/x509_vfy.h>\r
+#include <openssl/x509v3.h>\r
+#include <xmltooling/security/OpenSSLCryptoX509CRL.h>\r
+#include <xmltooling/signature/SignatureValidator.h>\r
+#include <xmltooling/util/NDC.h>\r
+#include <xsec/enc/OpenSSL/OpenSSLCryptoX509.hpp>\r
+#include <log4cpp/Category.hh>\r
+\r
+using namespace opensaml::saml2md;\r
+using namespace opensaml;\r
+using namespace xmlsignature;\r
+using namespace xmltooling;\r
+using namespace log4cpp;\r
+using namespace std;\r
+\r
+AbstractPKIXTrustEngine::AbstractPKIXTrustEngine(const DOMElement* e) : X509TrustEngine(e), m_inlineResolver(NULL)\r
+{\r
+ m_inlineResolver = XMLToolingConfig::getConfig().KeyResolverManager.newPlugin(INLINE_KEY_RESOLVER,NULL);\r
+}\r
+\r
+AbstractPKIXTrustEngine::~AbstractPKIXTrustEngine()\r
+{\r
+ delete m_inlineResolver;\r
+}\r
+\r
+namespace {\r
+ static int SAML_DLLLOCAL error_callback(int ok, X509_STORE_CTX* ctx)\r
+ {\r
+ if (!ok)\r
+ Category::getInstance("OpenSSL").error("path validation failure: %s", X509_verify_cert_error_string(ctx->error));\r
+ return ok;\r
+ }\r
+\r
+ static bool SAML_DLLLOCAL validate(\r
+ X509* EE, STACK_OF(X509)* untrusted, AbstractPKIXTrustEngine::PKIXValidationInfoIterator* pkixInfo\r
+ )\r
+ {\r
+ Category& log=Category::getInstance(SAML_LOGCAT".TrustEngine");\r
+ \r
+ // First we build a stack of CA certs. These objects are all referenced in place.\r
+ log.debug("building CA list from PKIX Validation information");\r
+ \r
+ // We need this for CRL support.\r
+ X509_STORE* store=X509_STORE_new();\r
+ if (!store) {\r
+ log_openssl();\r
+ return false;\r
+ }\r
+ #if (OPENSSL_VERSION_NUMBER >= 0x00907000L)\r
+ X509_STORE_set_flags(store,X509_V_FLAG_CRL_CHECK_ALL);\r
+ #endif\r
+ \r
+ STACK_OF(X509)* CAstack = sk_X509_new_null();\r
+ \r
+ // This contains the state of the validate operation.\r
+ X509_STORE_CTX ctx;\r
+ \r
+ const vector<XSECCryptoX509*>& CAcerts = pkixInfo->getTrustAnchors();\r
+ for (vector<XSECCryptoX509*>::const_iterator i=CAcerts.begin(); i!=CAcerts.end(); ++i) {\r
+ if ((*i)->getProviderName()==DSIGConstants::s_unicodeStrPROVOpenSSL) {\r
+ sk_X509_push(CAstack,static_cast<OpenSSLCryptoX509*>(*i)->getOpenSSLX509());\r
+ }\r
+ }\r
+\r
+ const vector<XSECCryptoX509CRL*>& crls = pkixInfo->getCRLs();\r
+ for (vector<XSECCryptoX509CRL*>::const_iterator j=crls.begin(); j!=crls.end(); ++j) {\r
+ if ((*j)->getProviderName()==DSIGConstants::s_unicodeStrPROVOpenSSL) {\r
+ // owned by store\r
+ X509_STORE_add_crl(\r
+ store,\r
+ X509_CRL_dup(static_cast<OpenSSLCryptoX509CRL*>(*j)->getOpenSSLX509CRL())\r
+ );\r
+ }\r
+ }\r
+ \r
+ // AFAICT, EE and untrusted are passed in but not owned by the ctx.\r
+ #if (OPENSSL_VERSION_NUMBER >= 0x00907000L)\r
+ if (X509_STORE_CTX_init(&ctx,store,EE,untrusted)!=1) {\r
+ log_openssl();\r
+ log.error("unable to initialize X509_STORE_CTX");\r
+ sk_X509_free(CAstack);\r
+ X509_STORE_free(store);\r
+ return false;\r
+ }\r
+ #else\r
+ X509_STORE_CTX_init(&ctx,store,EE,untrusted);\r
+ #endif\r
+ \r
+ // Seems to be most efficient to just pass in the CA stack.\r
+ X509_STORE_CTX_trusted_stack(&ctx,CAstack);\r
+ X509_STORE_CTX_set_depth(&ctx,100); // we check the depth down below\r
+ X509_STORE_CTX_set_verify_cb(&ctx,error_callback);\r
+ \r
+ int ret=X509_verify_cert(&ctx);\r
+ if (ret==1) {\r
+ // Now see if the depth was acceptable by counting the number of intermediates.\r
+ int depth=sk_X509_num(ctx.chain)-2;\r
+ if (pkixInfo->getVerificationDepth() < depth) {\r
+ log.error(\r
+ "certificate chain was too long (%d intermediates, only %d allowed)",\r
+ (depth==-1) ? 0 : depth,\r
+ pkixInfo->getVerificationDepth()\r
+ );\r
+ ret=0;\r
+ }\r
+ }\r
+ \r
+ // Clean up...\r
+ X509_STORE_CTX_cleanup(&ctx);\r
+ X509_STORE_free(store);\r
+ sk_X509_free(CAstack);\r
+ \r
+ if (ret==1) {\r
+ log.info("successfully validated certificate chain");\r
+ return true;\r
+ }\r
+ \r
+ return false;\r
+ }\r
+};\r
+\r
+bool AbstractPKIXTrustEngine::checkEntityNames(XSECCryptoX509* certEE, const RoleDescriptor& role) const\r
+{\r
+ Category& log=Category::getInstance(SAML_LOGCAT".TrustEngine");\r
+ \r
+ // Build a list of acceptable names. Transcode the possible key "names" to UTF-8.\r
+ // For some simple cases, this should handle UTF-8 encoded DNs in certificates.\r
+ vector<string> keynames;\r
+ const vector<KeyDescriptor*>& keydescs=role.getKeyDescriptors();\r
+ for (vector<KeyDescriptor*>::const_iterator kd_i=keydescs.begin(); kd_i!=keydescs.end(); ++kd_i) {\r
+ const XMLCh* use=(*kd_i)->getUse();\r
+ const KeyInfo* keyInfo = (*kd_i)->getKeyInfo();\r
+ if (keyInfo && use && XMLString::equals(use,KeyDescriptor::KEYTYPE_ENCRYPTION))\r
+ continue;\r
+ const vector<KeyName*>& knames=keyInfo->getKeyNames();\r
+ for (vector<KeyName*>::const_iterator kn_i=knames.begin(); kn_i!=knames.end(); ++kn_i) {\r
+ const XMLCh* n=(*kn_i)->getName();\r
+ if (n && *n) {\r
+ char* kn=toUTF8(n);\r
+ keynames.push_back(kn);\r
+ delete[] kn;\r
+ }\r
+ }\r
+ }\r
+ \r
+ EntityDescriptor* parent=dynamic_cast<EntityDescriptor*>(role.getParent());\r
+ if (parent) {\r
+ const XMLCh* eid=parent->getEntityID();\r
+ if (eid && *eid) {\r
+ char* kn=toUTF8(eid);\r
+ keynames.push_back(kn);\r
+ delete[] kn;\r
+ }\r
+ }\r
+ \r
+ char buf[256];\r
+ X509* x=static_cast<OpenSSLCryptoX509*>(certEE)->getOpenSSLX509();\r
+ X509_NAME* subject=X509_get_subject_name(x);\r
+ if (subject) {\r
+ // One way is a direct match to the subject DN.\r
+ // Seems that the way to do the compare is to write the X509_NAME into a BIO.\r
+ BIO* b = BIO_new(BIO_s_mem());\r
+ BIO* b2 = BIO_new(BIO_s_mem());\r
+ BIO_set_mem_eof_return(b, 0);\r
+ BIO_set_mem_eof_return(b2, 0);\r
+ // The flags give us LDAP order instead of X.500, with a comma separator.\r
+ int len=X509_NAME_print_ex(b,subject,0,XN_FLAG_RFC2253);\r
+ string subjectstr,subjectstr2;\r
+ BIO_flush(b);\r
+ while ((len = BIO_read(b, buf, 255)) > 0) {\r
+ buf[len] = '\0';\r
+ subjectstr+=buf;\r
+ }\r
+ log.infoStream() << "certificate subject: " << subjectstr << CategoryStream::ENDLINE;\r
+ // The flags give us LDAP order instead of X.500, with a comma plus space separator.\r
+ len=X509_NAME_print_ex(b2,subject,0,XN_FLAG_RFC2253 + XN_FLAG_SEP_CPLUS_SPC - XN_FLAG_SEP_COMMA_PLUS);\r
+ BIO_flush(b2);\r
+ while ((len = BIO_read(b2, buf, 255)) > 0) {\r
+ buf[len] = '\0';\r
+ subjectstr2+=buf;\r
+ }\r
+ \r
+ // Check each keyname.\r
+ for (vector<string>::const_iterator n=keynames.begin(); n!=keynames.end(); n++) {\r
+#ifdef HAVE_STRCASECMP\r
+ if (!strcasecmp(n->c_str(),subjectstr.c_str()) || !strcasecmp(n->c_str(),subjectstr2.c_str())) {\r
+#else\r
+ if (!stricmp(n->c_str(),subjectstr.c_str()) || !stricmp(n->c_str(),subjectstr2.c_str())) {\r
+#endif\r
+ log.info("matched full subject DN to a key name (%s)", n->c_str());\r
+ BIO_free(b);\r
+ BIO_free(b2);\r
+ return true;\r
+ }\r
+ }\r
+ BIO_free(b);\r
+ BIO_free(b2);\r
+\r
+ log.debug("unable to match DN, trying TLS subjectAltName match");\r
+ STACK_OF(GENERAL_NAME)* altnames=(STACK_OF(GENERAL_NAME)*)X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);\r
+ if (altnames) {\r
+ int numalts = sk_GENERAL_NAME_num(altnames);\r
+ for (int an=0; an<numalts; an++) {\r
+ const GENERAL_NAME* check = sk_GENERAL_NAME_value(altnames, an);\r
+ if (check->type==GEN_DNS || check->type==GEN_URI) {\r
+ const char* altptr = (char*)ASN1_STRING_data(check->d.ia5);\r
+ const int altlen = ASN1_STRING_length(check->d.ia5);\r
+ \r
+ for (vector<string>::const_iterator n=keynames.begin(); n!=keynames.end(); n++) {\r
+#ifdef HAVE_STRCASECMP\r
+ if ((check->type==GEN_DNS && !strncasecmp(altptr,n->c_str(),altlen))\r
+#else\r
+ if ((check->type==GEN_DNS && !strnicmp(altptr,n->c_str(),altlen))\r
+#endif\r
+ || (check->type==GEN_URI && !strncmp(altptr,n->c_str(),altlen))) {\r
+ log.info("matched DNS/URI subjectAltName to a key name (%s)", n->c_str());\r
+ GENERAL_NAMES_free(altnames);\r
+ return true;\r
+ }\r
+ }\r
+ }\r
+ }\r
+ }\r
+ GENERAL_NAMES_free(altnames);\r
+ \r
+ log.debug("unable to match subjectAltName, trying TLS CN match");\r
+ memset(buf,0,sizeof(buf));\r
+ if (X509_NAME_get_text_by_NID(subject,NID_commonName,buf,255)>0) {\r
+ for (vector<string>::const_iterator n=keynames.begin(); n!=keynames.end(); n++) {\r
+#ifdef HAVE_STRCASECMP\r
+ if (!strcasecmp(buf,n->c_str())) {\r
+#else\r
+ if (!stricmp(buf,n->c_str())) {\r
+#endif\r
+ log.info("matched subject CN to a key name (%s)", n->c_str());\r
+ return true;\r
+ }\r
+ }\r
+ }\r
+ else\r
+ log.warn("no common name in certificate subject");\r
+ }\r
+ else\r
+ log.error("certificate has no subject?!");\r
+ \r
+ return false;\r
+}\r
+\r
+bool AbstractPKIXTrustEngine::validate(\r
+ XSECCryptoX509* certEE,\r
+ const vector<XSECCryptoX509*>& certChain,\r
+ const RoleDescriptor& role,\r
+ bool checkName,\r
+ const KeyResolver* keyResolver\r
+ )\r
+{\r
+#ifdef _DEBUG\r
+ NDC ndc("validate");\r
+#endif\r
+ Category& log=Category::getInstance(SAML_LOGCAT".TrustEngine");\r
+\r
+ if (!certEE) {\r
+ log.error("X.509 credential was NULL, unable to perform validation");\r
+ return false;\r
+ }\r
+\r
+ if (checkName) {\r
+ log.debug("checking that the entity certificate name is acceptable");\r
+ if (!checkEntityNames(certEE,role)) {\r
+ log.error("entity certificate name was not acceptable");\r
+ return false;\r
+ }\r
+ }\r
+ \r
+ log.debug("performing certificate path validation...");\r
+\r
+ STACK_OF(X509)* untrusted=sk_X509_new_null();\r
+ for (vector<XSECCryptoX509*>::const_iterator i=certChain.begin(); i!=certChain.end(); ++i) {\r
+ sk_X509_push(untrusted,static_cast<OpenSSLCryptoX509*>(*i)->getOpenSSLX509());\r
+ }\r
+ \r
+ auto_ptr<PKIXValidationInfoIterator> pkix(getPKIXValidationInfoIterator(role));\r
+ while (pkix->next()) {\r
+ if (::validate(static_cast<OpenSSLCryptoX509*>(certEE)->getOpenSSLX509(),untrusted,pkix.get())) {\r
+ sk_X509_free(untrusted);\r
+ return true;\r
+ }\r
+ }\r
+\r
+ sk_X509_free(untrusted);\r
+ log.error("failed to validate certificate chain using supplied PKIX information");\r
+ return false;\r
+}\r
+\r
+bool AbstractPKIXTrustEngine::validate(Signature& sig, const RoleDescriptor& role, const KeyResolver* keyResolver)\r
+{\r
+#ifdef _DEBUG\r
+ NDC ndc("validate");\r
+#endif\r
+ Category& log=Category::getInstance(SAML_LOGCAT".TrustEngine");\r
+\r
+ log.debug("attempting to validate signature profile");\r
+ SignatureProfileValidator sigValidator;\r
+ try {\r
+ sigValidator.validate(&sig);\r
+ log.debug("signature profile validated");\r
+ }\r
+ catch (ValidationException& e) {\r
+ if (log.isDebugEnabled()) {\r
+ log.debug("signature profile failed to validate: %s", e.what());\r
+ }\r
+ return false;\r
+ }\r
+\r
+ // Pull the certificate chain out of the signature using an inline KeyResolver.\r
+ KeyResolver::ResolvedCertificates certs;\r
+ if (0==m_inlineResolver->resolveCertificates(&sig, certs)) {\r
+ log.error("unable to perform PKIX validation, signature does not contain any certificates");\r
+ return false;\r
+ }\r
+\r
+ log.debug("validating signature using certificate from within the signature");\r
+\r
+ // Find and save off a pointer to the certificate that unlocks the object.\r
+ // Most of the time, this will be the first one anyway.\r
+ XSECCryptoX509* certEE=NULL;\r
+ SignatureValidator keyValidator;\r
+ for (vector<XSECCryptoX509*>::const_iterator i=certs.v().begin(); !certEE && i!=certs.v().end(); ++i) {\r
+ try {\r
+ keyValidator.setKey((*i)->clonePublicKey());\r
+ keyValidator.validate(&sig);\r
+ log.info("signature verified with key inside signature, attempting certificate validation...");\r
+ certEE=(*i);\r
+ }\r
+ catch (ValidationException&) {\r
+ // trap failures\r
+ }\r
+ }\r
+ \r
+ if (certEE)\r
+ return validate(certEE,certs.v(),role,true,keyResolver);\r
+ \r
+ log.error("failed to verify signature with embedded certificates");\r
+ return false;\r
+}\r