xmltooling/security/impl/AbstractPKIXTrustEngine.cpp

   1 /**
   2  * Licensed to the University Corporation for Advanced Internet
   3  * Development, Inc. (UCAID) under one or more contributor license
   4  * agreements. See the NOTICE file distributed with this work for
   5  * additional information regarding copyright ownership.
   6  *
   7  * UCAID licenses this file to you under the Apache License,
   8  * Version 2.0 (the "License"); you may not use this file except
   9  * in compliance with the License. You may obtain a copy of the
  10  * License at
  11  *
  12  * http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  * Unless required by applicable law or agreed to in writing,
  15  * software distributed under the License is distributed on an
  16  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
  17  * either express or implied. See the License for the specific
  18  * language governing permissions and limitations under the License.
  19  */
  20
  21 /**
  22  * AbstractPKIXTrustEngine.cpp
  23  *
  24  * A trust engine that uses X.509 trust anchors and CRLs associated with a KeyInfoSource
  25  * to perform PKIX validation of signatures and certificates.
  26  */
  27
  28 #include "internal.h"
  29 #include "logging.h"
  30 #include "security/AbstractPKIXTrustEngine.h"
  31 #include "signature/KeyInfo.h"
  32 #include "signature/Signature.h"
  33 #include "security/CredentialCriteria.h"
  34 #include "security/CredentialResolver.h"
  35 #include "security/KeyInfoResolver.h"
  36 #include "security/OpenSSLCryptoX509CRL.h"
  37 #include "security/SecurityHelper.h"
  38 #include "security/X509Credential.h"
  39 #include "signature/SignatureValidator.h"
  40 #include "util/NDC.h"
  41 #include "util/PathResolver.h"
  42
  43 #include <fstream>
  44 #include <openssl/x509_vfy.h>
  45 #include <openssl/x509v3.h>
  46 #include <xercesc/util/XMLUniDefs.hpp>
  47 #include <xsec/enc/OpenSSL/OpenSSLCryptoX509.hpp>
  48
  49 using namespace xmlsignature;
  50 using namespace xmltooling::logging;
  51 using namespace xmltooling;
  52 using namespace std;
  53
  54
  55 namespace {
  56     static int XMLTOOL_DLLLOCAL error_callback(int ok, X509_STORE_CTX* ctx)
  57     {
  58         if (!ok)
  59             Category::getInstance("OpenSSL").error("path validation failure: %s", X509_verify_cert_error_string(ctx->error));
  60         return ok;
  61     }
  62
  63     static string XMLTOOL_DLLLOCAL X509_NAME_to_string(X509_NAME* n)
  64     {
  65         string s;
  66         BIO* b = BIO_new(BIO_s_mem());
  67         X509_NAME_print_ex(b,n,0,XN_FLAG_RFC2253);
  68         BIO_flush(b);
  69         BUF_MEM* bptr=nullptr;
  70         BIO_get_mem_ptr(b, &bptr);
  71         if (bptr && bptr->length > 0) {
  72             s.append(bptr->data, bptr->length);
  73         }
  74         BIO_free(b);
  75         return s;
  76     }
  77
  78     static time_t XMLTOOL_DLLLOCAL getCRLTime(const ASN1_TIME *a)
  79     {
  80         struct tm t;
  81         memset(&t, 0, sizeof(t));
  82         // RFC 5280, sections 5.1.2.4 and 5.1.2.5 require thisUpdate and nextUpdate
  83         // to be encoded as UTCTime until 2049, and RFC 5280 section 4.1.2.5.1
  84         // further restricts the format to "YYMMDDHHMMSSZ" ("even where the number
  85         // of seconds is zero").
  86         // As long as OpenSSL doesn't provide any API to convert ASN1_TIME values
  87         // time_t, we therefore have to parse it ourselves, unfortunately.
  88         if (sscanf((const char*)a->data, "%2d%2d%2d%2d%2d%2dZ",
  89             &t.tm_year, &t.tm_mon, &t.tm_mday,
  90             &t.tm_hour, &t.tm_min, &t.tm_sec) == 6) {
  91             if (t.tm_year <= 50) {
  92                 // RFC 5280, section 4.1.2.5.1
  93                 t.tm_year += 100;
  94             }
  95             t.tm_mon--;
  96 #if defined(HAVE_TIMEGM)
  97             return timegm(&t);
  98 #else
  99             // Windows, and hopefully most others...?
 100             return mktime(&t) - timezone;
 101 #endif
 102         }
 103         return (time_t)-1;
 104     }
 105
 106     static bool XMLTOOL_DLLLOCAL isFreshCRL(XSECCryptoX509CRL *c, Category* log=nullptr)
 107     {
 108         // eventually, these should be made configurable
 109         #define MIN_SECS_REMAINING 86400
 110         #define MIN_PERCENT_REMAINING 10
 111         if (c) {
 112             const X509_CRL* crl = static_cast<OpenSSLCryptoX509CRL*>(c)->getOpenSSLX509CRL();
 113             time_t thisUpdate = getCRLTime(X509_CRL_get_lastUpdate(crl));
 114             time_t nextUpdate = getCRLTime(X509_CRL_get_nextUpdate(crl));
 115             time_t now = time(nullptr);
 116
 117             if (thisUpdate < 0 || nextUpdate < 0) {
 118                 // we failed to parse at least one of the fields (they were not encoded
 119                 // as required by RFC 5280, actually)
 120                 time_t exp = now + MIN_SECS_REMAINING;
 121                 if (log) {
 122                     log->warn("isFreshCRL (issuer '%s'): improperly encoded thisUpdate or nextUpdate field - falling back to simple time comparison",
 123                               (X509_NAME_to_string(X509_CRL_get_issuer(crl))).c_str());
 124                 }
 125                 return (X509_cmp_time(X509_CRL_get_nextUpdate(crl), &exp) > 0) ? true : false;
 126             }
 127             else {
 128                 if (log && log->isDebugEnabled()) {
 129                     log->debug("isFreshCRL (issuer '%s'): %.0f seconds until nextUpdate (%3.2f%% elapsed since thisUpdate)",
 130                               (X509_NAME_to_string(X509_CRL_get_issuer(crl))).c_str(),
 131                               difftime(nextUpdate, now), (difftime(now, thisUpdate) * 100) / difftime(nextUpdate, thisUpdate));
 132                 }
 133
 134                 // consider it recent enough if there are at least MIN_SECS_REMAINING
 135                 // to the nextUpdate, and at least MIN_PERCENT_REMAINING of its
 136                 // overall "validity" are remaining to the nextUpdate
 137                 return (now + MIN_SECS_REMAINING < nextUpdate) &&
 138                         ((difftime(nextUpdate, now) * 100) / difftime(nextUpdate, thisUpdate) > MIN_PERCENT_REMAINING);
 139             }
 140         }
 141         return false;
 142     }
 143
 144     static XSECCryptoX509CRL* XMLTOOL_DLLLOCAL getRemoteCRLs(const char* cdpuri, Category& log) {
 145         // This is a temporary CRL cache implementation to avoid breaking binary compatibility
 146         // for the library. Caching can't rely on any member objects within the TrustEngine,
 147         // including locks, so we're using the global library lock for the time being.
 148         // All other state is kept in the file system.
 149
 150         // minimum number of seconds between re-attempting a download from one particular CRLDP
 151         #define MIN_RETRY_WAIT 60
 152
 153         // The filenames for the CRL cache are based on a hash of the CRL location.
 154         string cdpfile = SecurityHelper::doHash("SHA1", cdpuri, strlen(cdpuri)) + ".crl";
 155         XMLToolingConfig::getConfig().getPathResolver()->resolve(cdpfile, PathResolver::XMLTOOLING_RUN_FILE);
 156         string cdpstaging = cdpfile + ".tmp";
 157         string tsfile = cdpfile + ".ts";
 158
 159         time_t now = time(nullptr);
 160         vector<XSECCryptoX509CRL*> crls;
 161
 162         try {
 163             // While holding the lock, check for a cached copy of the CRL, and remove "expired" ones.
 164             Locker glock(&XMLToolingConfig::getConfig());
 165 #ifdef WIN32
 166             struct _stat stat_buf;
 167             if (_stat(cdpfile.c_str(), &stat_buf) == 0) {
 168 #else
 169             struct stat stat_buf;
 170             if (stat(cdpfile.c_str(), &stat_buf) == 0) {
 171 #endif
 172                 SecurityHelper::loadCRLsFromFile(crls, cdpfile.c_str());
 173                 if (crls.empty() || crls.front()->getProviderName() != DSIGConstants::s_unicodeStrPROVOpenSSL ||
 174                     X509_cmp_time(X509_CRL_get_nextUpdate(static_cast<OpenSSLCryptoX509CRL*>(crls.front())->getOpenSSLX509CRL()), &now) < 0) {
 175                     for_each(crls.begin(), crls.end(), xmltooling::cleanup<XSECCryptoX509CRL>());
 176                     crls.clear();
 177                     remove(cdpfile.c_str());    // may as well delete the local copy
 178                     remove(tsfile.c_str());
 179                     log.info("deleting cached CRL from %s with nextUpdate field in the past", cdpuri);
 180                 }
 181             }
 182         }
 183         catch (exception& ex) {
 184             log.error("exception loading cached copy of CRL from %s: %s", cdpuri, ex.what());
 185         }
 186
 187         if (crls.empty() || !isFreshCRL(crls.front(), &log)) {
 188             bool updateTimestamp = true;
 189             try {
 190                 // If we get here, the cached copy didn't exist yet, or it's time to refresh.
 191                 // To limit the rate of unsuccessful attempts when a CRLDP is unreachable,
 192                 // we remember the timestamp of the last attempt (both successful/unsuccessful).
 193                 // We store this in the file system because of the binary compatibility issue.
 194                 time_t ts = 0;
 195                 try {
 196                     Locker glock(&XMLToolingConfig::getConfig());
 197                     ifstream tssrc(tsfile.c_str());
 198                     if (tssrc)
 199                         tssrc >> ts;
 200                 }
 201                 catch (exception&) {
 202                     ts = 0;
 203                 }
 204
 205                 if (difftime(now, ts) > MIN_RETRY_WAIT) {
 206                     SOAPTransport::Address addr("AbstractPKIXTrustEngine", cdpuri, cdpuri);
 207                     string scheme(addr.m_endpoint, strchr(addr.m_endpoint,':') - addr.m_endpoint);
 208                     auto_ptr<SOAPTransport> soap(XMLToolingConfig::getConfig().SOAPTransportManager.newPlugin(scheme.c_str(), addr));
 209                     soap->send();
 210                     istream& msg = soap->receive();
 211                     Locker glock(&XMLToolingConfig::getConfig());
 212                     ofstream out(cdpstaging.c_str(), fstream::trunc|fstream::binary);
 213                     out << msg.rdbuf();
 214                     out.close();
 215                     SecurityHelper::loadCRLsFromFile(crls, cdpstaging.c_str());
 216                     if (crls.empty() || crls.front()->getProviderName() != DSIGConstants::s_unicodeStrPROVOpenSSL ||
 217                         X509_cmp_time(X509_CRL_get_nextUpdate(static_cast<OpenSSLCryptoX509CRL*>(crls.front())->getOpenSSLX509CRL()), &now) < 0) {
 218                         // The "new" CRL wasn't usable, so get rid of it.
 219                         for_each(crls.begin(), crls.end(), xmltooling::cleanup<XSECCryptoX509CRL>());
 220                         crls.clear();
 221                         remove(cdpstaging.c_str());
 222                         log.error("ignoring CRL retrieved from %s with nextUpdate field in the past", cdpuri);
 223                     }
 224                     else {
 225                         // "Commit" the new CRL. Note that we might add a CRL which doesn't pass
 226                         // isFreshCRL, but that's preferrable over adding none at all.
 227                         log.info("CRL refreshed from %s", cdpuri);
 228                         remove(cdpfile.c_str());
 229                         if (rename(cdpstaging.c_str(), cdpfile.c_str()) != 0)
 230                             log.error("unable to rename CRL staging file");
 231                     }
 232                 }
 233                 else {
 234                     updateTimestamp = false;    // don't update if we're within the backoff window
 235                 }
 236             }
 237             catch (exception& ex) {
 238                 log.error("exception downloading/caching CRL from %s: %s", cdpuri, ex.what());
 239             }
 240
 241             if (updateTimestamp) {
 242                 // update the timestamp file
 243                 Locker glock(&XMLToolingConfig::getConfig());
 244                 ofstream tssink(tsfile.c_str(), fstream::trunc);
 245                 tssink << now;
 246                 tssink.close();
 247             }
 248         }
 249
 250         if (crls.empty())
 251             return nullptr;
 252         for_each(crls.begin() + 1, crls.end(), xmltooling::cleanup<XSECCryptoX509CRL>());
 253         return crls.front();
 254     }
 255
 256     static bool XMLTOOL_DLLLOCAL validate(
 257         X509* EE,
 258         STACK_OF(X509)* untrusted,
 259         AbstractPKIXTrustEngine::PKIXValidationInfoIterator* pkixInfo,
 260         bool useCRL,
 261         bool fullCRLChain,
 262         const vector<XSECCryptoX509CRL*>* inlineCRLs=nullptr,
 263         bool policyMappingInhibit=false,
 264         bool anyPolicyInhibit=false,
 265         const set<string>* policyOIDs=nullptr
 266         )
 267     {
 268         Category& log=Category::getInstance(XMLTOOLING_LOGCAT".TrustEngine");
 269
 270         // First we build a stack of CA certs. These objects are all referenced in place.
 271         log.debug("supplying PKIX Validation information");
 272
 273         // We need this for CRL support.
 274         X509_STORE* store=X509_STORE_new();
 275         if (!store) {
 276             log_openssl();
 277             return false;
 278         }
 279
 280         // PKIX policy checking (cf. RFCs 3280/5280 section 6)
 281         if (policyMappingInhibit || anyPolicyInhibit || (policyOIDs && !policyOIDs->empty())) {
 282 #if (OPENSSL_VERSION_NUMBER < 0x00908000L)
 283             log.error("PKIX policy checking option is configured, but OpenSSL version is less than 0.9.8");
 284             X509_STORE_free(store);
 285             return false;
 286 #else
 287             unsigned long pflags = 0;
 288             X509_VERIFY_PARAM *vpm = X509_VERIFY_PARAM_new();
 289             if (!vpm) {
 290                 log_openssl();
 291                 X509_STORE_free(store);
 292                 return false;
 293             }
 294
 295             // populate the "user-initial-policy-set" input variable
 296             if (policyOIDs && !policyOIDs->empty()) {
 297                 for (set<string>::const_iterator o=policyOIDs->begin(); o!=policyOIDs->end(); o++) {
 298                     ASN1_OBJECT *oid = OBJ_txt2obj(o->c_str(), 1);
 299                     if (oid && X509_VERIFY_PARAM_add0_policy(vpm, oid)) {
 300                         log.debug("OID (%s) added to set of acceptable policies", o->c_str());
 301                     }
 302                     else {
 303                         log_openssl();
 304                         log.error("unable to parse/configure policy OID value (%s)", o->c_str());
 305                         if (oid)
 306                             ASN1_OBJECT_free(oid);
 307                         X509_VERIFY_PARAM_free(vpm);
 308                         X509_STORE_free(store);
 309                         return false;
 310                     }
 311                 }
 312                 // when the user has supplied at least one policy OID, he obviously wants to check
 313                 // for an explicit policy ("initial-explicit-policy")
 314                 pflags |= X509_V_FLAG_EXPLICIT_POLICY;
 315             }
 316
 317             // "initial-policy-mapping-inhibit" input variable
 318             if (policyMappingInhibit)
 319                 pflags |= X509_V_FLAG_INHIBIT_MAP;
 320             // "initial-any-policy-inhibit" input variable
 321             if (anyPolicyInhibit)
 322                 pflags |= X509_V_FLAG_INHIBIT_ANY;
 323
 324             if (!X509_VERIFY_PARAM_set_flags(vpm, pflags) || !X509_STORE_set1_param(store, vpm)) {
 325                 log_openssl();
 326                 log.error("unable to set PKIX policy checking parameters");
 327                 X509_VERIFY_PARAM_free(vpm);
 328                 X509_STORE_free(store);
 329                 return false;
 330             }
 331
 332             X509_VERIFY_PARAM_free(vpm);
 333 #endif
 334         }
 335
 336         // This contains the state of the validate operation.
 337         int count=0;
 338         X509_STORE_CTX ctx;
 339
 340         // AFAICT, EE and untrusted are passed in but not owned by the ctx.
 341 #if (OPENSSL_VERSION_NUMBER >= 0x00907000L)
 342         if (X509_STORE_CTX_init(&ctx,store,EE,untrusted)!=1) {
 343             log_openssl();
 344             log.error("unable to initialize X509_STORE_CTX");
 345             X509_STORE_free(store);
 346             return false;
 347         }
 348 #else
 349         X509_STORE_CTX_init(&ctx,store,EE,untrusted);
 350 #endif
 351
 352         STACK_OF(X509)* CAstack = sk_X509_new_null();
 353         const vector<XSECCryptoX509*>& CAcerts = pkixInfo->getTrustAnchors();
 354         for (vector<XSECCryptoX509*>::const_iterator i=CAcerts.begin(); i!=CAcerts.end(); ++i) {
 355             if ((*i)->getProviderName()==DSIGConstants::s_unicodeStrPROVOpenSSL) {
 356                 sk_X509_push(CAstack,static_cast<OpenSSLCryptoX509*>(*i)->getOpenSSLX509());
 357                 ++count;
 358             }
 359         }
 360         log.debug("supplied (%d) CA certificate(s)", count);
 361
 362         // Seems to be most efficient to just pass in the CA stack.
 363         X509_STORE_CTX_trusted_stack(&ctx,CAstack);
 364         X509_STORE_CTX_set_depth(&ctx,100);    // we check the depth down below
 365         X509_STORE_CTX_set_verify_cb(&ctx,error_callback);
 366
 367         // Do a first pass verify. If CRLs aren't used, this is the only pass.
 368         int ret=X509_verify_cert(&ctx);
 369         if (ret==1) {
 370             // Now see if the depth was acceptable by counting the number of intermediates.
 371             int depth=sk_X509_num(ctx.chain)-2;
 372             if (pkixInfo->getVerificationDepth() < depth) {
 373                 log.error(
 374                     "certificate chain was too long (%d intermediates, only %d allowed)",
 375                     (depth==-1) ? 0 : depth,
 376                     pkixInfo->getVerificationDepth()
 377                     );
 378                 ret=0;
 379             }
 380         }
 381
 382         if (useCRL) {
 383 #if (OPENSSL_VERSION_NUMBER >= 0x00907000L)
 384             // When we add CRLs, we have to be sure the nextUpdate hasn't passed, because OpenSSL won't accept
 385             // the CRL in that case. If we end up not adding a CRL for a particular link in the chain, the
 386             // validation will fail (if the fullChain option was set).
 387             set<string> crlissuers;
 388             time_t now = time(nullptr);
 389             if (inlineCRLs) {
 390                 for (vector<XSECCryptoX509CRL*>::const_iterator j=inlineCRLs->begin(); j!=inlineCRLs->end(); ++j) {
 391                     if ((*j)->getProviderName()==DSIGConstants::s_unicodeStrPROVOpenSSL &&
 392                         (X509_cmp_time(X509_CRL_get_nextUpdate(static_cast<OpenSSLCryptoX509CRL*>(*j)->getOpenSSLX509CRL()), &now) > 0)) {
 393                         // owned by store
 394                         X509_STORE_add_crl(store, X509_CRL_dup(static_cast<OpenSSLCryptoX509CRL*>(*j)->getOpenSSLX509CRL()));
 395                         string crlissuer(X509_NAME_to_string(X509_CRL_get_issuer(static_cast<OpenSSLCryptoX509CRL*>(*j)->getOpenSSLX509CRL())));
 396                         if (!crlissuer.empty()) {
 397                             log.debug("added inline CRL issued by (%s)", crlissuer.c_str());
 398                             crlissuers.insert(crlissuer);
 399                         }
 400                     }
 401                 }
 402             }
 403             const vector<XSECCryptoX509CRL*>& crls = pkixInfo->getCRLs();
 404             for (vector<XSECCryptoX509CRL*>::const_iterator j=crls.begin(); j!=crls.end(); ++j) {
 405                 if ((*j)->getProviderName()==DSIGConstants::s_unicodeStrPROVOpenSSL &&
 406                     (X509_cmp_time(X509_CRL_get_nextUpdate(static_cast<OpenSSLCryptoX509CRL*>(*j)->getOpenSSLX509CRL()), &now) > 0)) {
 407                     // owned by store
 408                     X509_STORE_add_crl(store, X509_CRL_dup(static_cast<OpenSSLCryptoX509CRL*>(*j)->getOpenSSLX509CRL()));
 409                     string crlissuer(X509_NAME_to_string(X509_CRL_get_issuer(static_cast<OpenSSLCryptoX509CRL*>(*j)->getOpenSSLX509CRL())));
 410                     if (!crlissuer.empty()) {
 411                         log.debug("added CRL issued by (%s)", crlissuer.c_str());
 412                         crlissuers.insert(crlissuer);
 413                     }
 414                 }
 415             }
 416
 417             for (int i = 0; i < sk_X509_num(untrusted); ++i) {
 418                 X509 *cert = sk_X509_value(untrusted, i);
 419                 string crlissuer(X509_NAME_to_string(X509_get_issuer_name(cert)));
 420                 if (crlissuers.count(crlissuer)) {
 421                    // We already have a CRL for this cert, so skip CRLDP processing for this one.
 422                    continue;
 423                 }
 424
 425                 bool foundUsableCDP = false;
 426                 STACK_OF(DIST_POINT)* dps = (STACK_OF(DIST_POINT)*)X509_get_ext_d2i(cert, NID_crl_distribution_points, nullptr, nullptr);
 427                 for (int ii = 0; !foundUsableCDP && ii < sk_DIST_POINT_num(dps); ++ii) {
 428                     DIST_POINT* dp = sk_DIST_POINT_value(dps, ii);
 429                     if (!dp->distpoint || dp->distpoint->type != 0)
 430                         continue;
 431                     for (int iii = 0; !foundUsableCDP && iii < sk_GENERAL_NAME_num(dp->distpoint->name.fullname); ++iii) {
 432                         GENERAL_NAME* gen = sk_GENERAL_NAME_value(dp->distpoint->name.fullname, iii);
 433                         // Only consider HTTP URIs, and stop after the first one we find.
 434 #ifdef HAVE_STRCASECMP
 435                         if (gen->type == GEN_URI && (!strncasecmp((const char*)gen->d.ia5->data, "http:", 5))) {
 436 #else
 437                         if (gen->type == GEN_URI && (!strnicmp((const char*)gen->d.ia5->data, "http:", 5))) {
 438 #endif
 439                             const char* cdpuri = (const char*)gen->d.ia5->data;
 440                             auto_ptr<XSECCryptoX509CRL> crl(getRemoteCRLs(cdpuri, log));
 441                             if (crl.get() && crl->getProviderName()==DSIGConstants::s_unicodeStrPROVOpenSSL &&
 442                                 (isFreshCRL(crl.get()) || (ii == sk_DIST_POINT_num(dps)-1 && iii == sk_GENERAL_NAME_num(dp->distpoint->name.fullname)-1))) {
 443                                 // owned by store
 444                                 X509_STORE_add_crl(store, X509_CRL_dup(static_cast<OpenSSLCryptoX509CRL*>(crl.get())->getOpenSSLX509CRL()));
 445                                 log.debug("added CRL issued by (%s)", crlissuer.c_str());
 446                                 crlissuers.insert(crlissuer);
 447                                 foundUsableCDP = true;
 448                             }
 449                         }
 450                     }
 451                 }
 452                 sk_DIST_POINT_free(dps);
 453             }
 454
 455             // Do a second pass verify with CRLs in place.
 456             X509_STORE_CTX_set_flags(&ctx, fullCRLChain ? (X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL) : (X509_V_FLAG_CRL_CHECK));
 457             ret=X509_verify_cert(&ctx);
 458 #else
 459             log.warn("CRL checking is enabled, but OpenSSL version is too old");
 460             ret = 0;
 461 #endif
 462         }
 463
 464         // Clean up...
 465         X509_STORE_CTX_cleanup(&ctx);
 466         X509_STORE_free(store);
 467         sk_X509_free(CAstack);
 468
 469         if (ret==1) {
 470             log.debug("successfully validated certificate chain");
 471             return true;
 472         }
 473
 474         return false;
 475     }
 476
 477     static XMLCh fullCRLChain[] =                   UNICODE_LITERAL_12(f,u,l,l,C,R,L,C,h,a,i,n);
 478     static XMLCh checkRevocation[] =        UNICODE_LITERAL_15(c,h,e,c,k,R,e,v,o,c,a,t,i,o,n);
 479     static XMLCh policyMappingInhibit[] =   UNICODE_LITERAL_20(p,o,l,i,c,y,M,a,p,p,i,n,g,I,n,h,i,b,i,t);
 480     static XMLCh anyPolicyInhibit[] =       UNICODE_LITERAL_16(a,n,y,P,o,l,i,c,y,I,n,h,i,b,i,t);
 481     static XMLCh PolicyOID[] =                      UNICODE_LITERAL_9(P,o,l,i,c,y,O,I,D);
 482     static XMLCh TrustedName[] =                    UNICODE_LITERAL_11(T,r,u,s,t,e,d,N,a,m,e);
 483 };
 484
 485 AbstractPKIXTrustEngine::PKIXValidationInfoIterator::PKIXValidationInfoIterator()
 486 {
 487 }
 488
 489 AbstractPKIXTrustEngine::PKIXValidationInfoIterator::~PKIXValidationInfoIterator()
 490 {
 491 }
 492
 493 AbstractPKIXTrustEngine::AbstractPKIXTrustEngine(const xercesc::DOMElement* e)
 494         : TrustEngine(e),
 495                 m_checkRevocation(XMLHelper::getAttrString(e, nullptr, checkRevocation)),
 496                 m_fullCRLChain(XMLHelper::getAttrBool(e, false, fullCRLChain)),
 497                 m_policyMappingInhibit(XMLHelper::getAttrBool(e, false, policyMappingInhibit)),
 498                 m_anyPolicyInhibit(XMLHelper::getAttrBool(e, false, anyPolicyInhibit))
 499 {
 500     if (m_fullCRLChain) {
 501         Category::getInstance(XMLTOOLING_LOGCAT".TrustEngine.PKIX").warn(
 502             "fullCRLChain option is deprecated, setting checkRevocation to \"fullChain\""
 503             );
 504         m_checkRevocation = "fullChain";
 505     }
 506     else if (m_checkRevocation == "fullChain") {
 507         m_fullCRLChain = true; // in case anything's using this
 508     }
 509
 510     xercesc::DOMElement* c = XMLHelper::getFirstChildElement(e);
 511     while (c) {
 512         if (c->hasChildNodes()) {
 513             auto_ptr_char v(c->getTextContent());
 514             if (v.get() && *v.get()) {
 515                 if (XMLString::equals(c->getLocalName(), PolicyOID))
 516                     m_policyOIDs.insert(v.get());
 517                 else if (XMLString::equals(c->getLocalName(), TrustedName))
 518                     m_trustedNames.insert(v.get());
 519             }
 520         }
 521         c = XMLHelper::getNextSiblingElement(c);
 522     }
 523 }
 524
 525 AbstractPKIXTrustEngine::~AbstractPKIXTrustEngine()
 526 {
 527 }
 528
 529 bool AbstractPKIXTrustEngine::checkEntityNames(
 530     X509* certEE, const CredentialResolver& credResolver, const CredentialCriteria& criteria
 531     ) const
 532 {
 533     Category& log=Category::getInstance(XMLTOOLING_LOGCAT".TrustEngine.PKIX");
 534
 535     // We resolve to a set of trusted credentials.
 536     vector<const Credential*> creds;
 537     credResolver.resolve(creds,&criteria);
 538
 539     // Build a list of acceptable names.
 540     set<string> trustednames = m_trustedNames;
 541     if (log.isDebugEnabled()) {
 542         for (set<string>::const_iterator n=m_trustedNames.begin(); n!=m_trustedNames.end(); n++) {
 543             log.debug("adding to list of trusted names (%s)", n->c_str());
 544         }
 545     }
 546     if (criteria.getPeerName()) {
 547         trustednames.insert(criteria.getPeerName());
 548         log.debug("adding to list of trusted names (%s)", criteria.getPeerName());
 549     }
 550     for (vector<const Credential*>::const_iterator cred = creds.begin(); cred!=creds.end(); ++cred) {
 551         trustednames.insert((*cred)->getKeyNames().begin(), (*cred)->getKeyNames().end());
 552         if (log.isDebugEnabled()) {
 553             for (set<string>::const_iterator n=(*cred)->getKeyNames().begin(); n!=(*cred)->getKeyNames().end(); n++) {
 554                 log.debug("adding to list of trusted names (%s)", n->c_str());
 555             }
 556         }
 557     }
 558
 559     X509_NAME* subject=X509_get_subject_name(certEE);
 560     if (subject) {
 561         // One way is a direct match to the subject DN.
 562         // Seems that the way to do the compare is to write the X509_NAME into a BIO.
 563         BIO* b = BIO_new(BIO_s_mem());
 564         BIO* b2 = BIO_new(BIO_s_mem());
 565         // The flags give us LDAP order instead of X.500, with a comma separator.
 566         X509_NAME_print_ex(b,subject,0,XN_FLAG_RFC2253);
 567         BIO_flush(b);
 568         // The flags give us LDAP order instead of X.500, with a comma plus space separator.
 569         X509_NAME_print_ex(b2,subject,0,XN_FLAG_RFC2253 + XN_FLAG_SEP_CPLUS_SPC - XN_FLAG_SEP_COMMA_PLUS);
 570         BIO_flush(b2);
 571
 572         BUF_MEM* bptr=nullptr;
 573         BUF_MEM* bptr2=nullptr;
 574         BIO_get_mem_ptr(b, &bptr);
 575         BIO_get_mem_ptr(b2, &bptr2);
 576
 577         if (bptr && bptr->length > 0 && log.isDebugEnabled()) {
 578             string subjectstr(bptr->data, bptr->length);
 579             log.debug("certificate subject: %s", subjectstr.c_str());
 580         }
 581
 582         // Check each keyname.
 583         for (set<string>::const_iterator n=trustednames.begin(); bptr && bptr2 && n!=trustednames.end(); n++) {
 584 #ifdef HAVE_STRCASECMP
 585             if ((n->length() == bptr->length && !strncasecmp(n->c_str(), bptr->data, bptr->length)) ||
 586                 (n->length() == bptr2->length && !strncasecmp(n->c_str(), bptr2->data, bptr2->length))) {
 587 #else
 588             if ((n->length() == bptr->length && !strnicmp(n->c_str(), bptr->data, bptr->length)) ||
 589                 (n->length() == bptr2->length && !strnicmp(n->c_str(), bptr2->data, bptr2->length))) {
 590 #endif
 591                 log.debug("matched full subject DN to a key name (%s)", n->c_str());
 592                 BIO_free(b);
 593                 BIO_free(b2);
 594                 return true;
 595             }
 596         }
 597         BIO_free(b);
 598         BIO_free(b2);
 599
 600         log.debug("unable to match DN, trying TLS subjectAltName match");
 601         STACK_OF(GENERAL_NAME)* altnames=(STACK_OF(GENERAL_NAME)*)X509_get_ext_d2i(certEE, NID_subject_alt_name, nullptr, nullptr);
 602         if (altnames) {
 603             int numalts = sk_GENERAL_NAME_num(altnames);
 604             for (int an=0; an<numalts; an++) {
 605                 const GENERAL_NAME* check = sk_GENERAL_NAME_value(altnames, an);
 606                 if (check->type==GEN_DNS || check->type==GEN_URI) {
 607                     const char* altptr = (char*)ASN1_STRING_data(check->d.ia5);
 608                     const int altlen = ASN1_STRING_length(check->d.ia5);
 609                     for (set<string>::const_iterator n=trustednames.begin(); n!=trustednames.end(); n++) {
 610 #ifdef HAVE_STRCASECMP
 611                         if ((check->type==GEN_DNS && n->length()==altlen && !strncasecmp(altptr,n->c_str(),altlen))
 612 #else
 613                         if ((check->type==GEN_DNS && n->length()==altlen && !strnicmp(altptr,n->c_str(),altlen))
 614 #endif
 615                                 || (check->type==GEN_URI && n->length()==altlen && !strncmp(altptr,n->c_str(),altlen))) {
 616                             log.debug("matched DNS/URI subjectAltName to a key name (%s)", n->c_str());
 617                             GENERAL_NAMES_free(altnames);
 618                             return true;
 619                         }
 620                     }
 621                 }
 622             }
 623         }
 624         GENERAL_NAMES_free(altnames);
 625
 626         log.debug("unable to match subjectAltName, trying TLS CN match");
 627
 628         // Fetch the last CN RDN.
 629         char* peer_CN = nullptr;
 630         int j,i = -1;
 631         while ((j=X509_NAME_get_index_by_NID(subject, NID_commonName, i)) >= 0)
 632             i = j;
 633         if (i >= 0) {
 634             ASN1_STRING* tmp = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(subject, i));
 635             // Copied in from libcurl.
 636             /* In OpenSSL 0.9.7d and earlier, ASN1_STRING_to_UTF8 fails if the input
 637                is already UTF-8 encoded. We check for this case and copy the raw
 638                string manually to avoid the problem. */
 639             if(tmp && ASN1_STRING_type(tmp) == V_ASN1_UTF8STRING) {
 640                 j = ASN1_STRING_length(tmp);
 641                 if(j >= 0) {
 642                     peer_CN = (char*)OPENSSL_malloc(j + 1);
 643                     memcpy(peer_CN, ASN1_STRING_data(tmp), j);
 644                     peer_CN[j] = '\0';
 645                 }
 646             }
 647             else /* not a UTF8 name */ {
 648                 j = ASN1_STRING_to_UTF8(reinterpret_cast<unsigned char**>(&peer_CN), tmp);
 649             }
 650
 651             for (set<string>::const_iterator n=trustednames.begin(); n!=trustednames.end(); n++) {
 652 #ifdef HAVE_STRCASECMP
 653                 if (n->length() == j && !strncasecmp(peer_CN, n->c_str(), j)) {
 654 #else
 655                 if (n->length() == j && !strnicmp(peer_CN, n->c_str(), j)) {
 656 #endif
 657                     log.debug("matched subject CN to a key name (%s)", n->c_str());
 658                     if(peer_CN)
 659                         OPENSSL_free(peer_CN);
 660                     return true;
 661                 }
 662             }
 663             if(peer_CN)
 664                 OPENSSL_free(peer_CN);
 665         }
 666         else {
 667             log.warn("no common name in certificate subject");
 668         }
 669     }
 670     else {
 671         log.error("certificate has no subject?!");
 672     }
 673
 674     return false;
 675 }
 676
 677 bool AbstractPKIXTrustEngine::validateWithCRLs(
 678     X509* certEE,
 679     STACK_OF(X509)* certChain,
 680     const CredentialResolver& credResolver,
 681     CredentialCriteria* criteria,
 682     const std::vector<XSECCryptoX509CRL*>* inlineCRLs
 683     ) const
 684 {
 685 #ifdef _DEBUG
 686     NDC ndc("validateWithCRLs");
 687 #endif
 688     Category& log=Category::getInstance(XMLTOOLING_LOGCAT".TrustEngine.PKIX");
 689
 690     if (!certEE) {
 691         log.error("X.509 credential was NULL, unable to perform validation");
 692         return false;
 693     }
 694
 695     if (criteria && criteria->getPeerName() && *(criteria->getPeerName())) {
 696         log.debug("checking that the certificate name is acceptable");
 697         if (criteria && criteria->getUsage()==Credential::UNSPECIFIED_CREDENTIAL)
 698             criteria->setUsage(Credential::SIGNING_CREDENTIAL);
 699         if (!checkEntityNames(certEE,credResolver,*criteria)) {
 700             log.error("certificate name was not acceptable");
 701             return false;
 702         }
 703     }
 704     else if (!m_trustedNames.empty()) {
 705         log.debug("checking that the certificate name is acceptable");
 706         CredentialCriteria cc;
 707         cc.setUsage(Credential::SIGNING_CREDENTIAL);
 708         if (!checkEntityNames(certEE,credResolver,cc)) {
 709             log.error("certificate name was not acceptable");
 710             return false;
 711         }
 712     }
 713
 714     log.debug("performing certificate path validation...");
 715
 716     auto_ptr<PKIXValidationInfoIterator> pkix(getPKIXValidationInfoIterator(credResolver, criteria));
 717     while (pkix->next()) {
 718         if (::validate(
 719                                 certEE,
 720                                 certChain,
 721                                 pkix.get(),
 722                                 (m_checkRevocation=="entityOnly" || m_checkRevocation=="fullChain"),
 723                                 (m_checkRevocation=="fullChain"),
 724                                 (m_checkRevocation=="entityOnly" || m_checkRevocation=="fullChain") ? inlineCRLs : nullptr,
 725                                 m_policyMappingInhibit,
 726                                 m_anyPolicyInhibit,
 727                                 &m_policyOIDs
 728                                 )) {
 729             return true;
 730         }
 731     }
 732
 733     log.debug("failed to validate certificate chain using supplied PKIX information");
 734     return false;
 735 }
 736
 737 bool AbstractPKIXTrustEngine::validate(
 738     X509* certEE,
 739     STACK_OF(X509)* certChain,
 740     const CredentialResolver& credResolver,
 741     CredentialCriteria* criteria
 742     ) const
 743 {
 744     return validateWithCRLs(certEE,certChain,credResolver,criteria);
 745 }
 746
 747 bool AbstractPKIXTrustEngine::validate(
 748     XSECCryptoX509* certEE,
 749     const vector<XSECCryptoX509*>& certChain,
 750     const CredentialResolver& credResolver,
 751     CredentialCriteria* criteria
 752     ) const
 753 {
 754 #ifdef _DEBUG
 755         NDC ndc("validate");
 756 #endif
 757     if (!certEE) {
 758         Category::getInstance(XMLTOOLING_LOGCAT".TrustEngine.PKIX").error("X.509 credential was NULL, unable to perform validation");
 759         return false;
 760     }
 761     else if (certEE->getProviderName()!=DSIGConstants::s_unicodeStrPROVOpenSSL) {
 762         Category::getInstance(XMLTOOLING_LOGCAT".TrustEngine.PKIX").error("only the OpenSSL XSEC provider is supported");
 763         return false;
 764     }
 765
 766     STACK_OF(X509)* untrusted=sk_X509_new_null();
 767     for (vector<XSECCryptoX509*>::const_iterator i=certChain.begin(); i!=certChain.end(); ++i)
 768         sk_X509_push(untrusted,static_cast<OpenSSLCryptoX509*>(*i)->getOpenSSLX509());
 769
 770     bool ret = validate(static_cast<OpenSSLCryptoX509*>(certEE)->getOpenSSLX509(), untrusted, credResolver, criteria);
 771     sk_X509_free(untrusted);
 772     return ret;
 773 }
 774
 775 bool AbstractPKIXTrustEngine::validate(
 776     Signature& sig,
 777     const CredentialResolver& credResolver,
 778     CredentialCriteria* criteria
 779     ) const
 780 {
 781 #ifdef _DEBUG
 782     NDC ndc("validate");
 783 #endif
 784     Category& log=Category::getInstance(XMLTOOLING_LOGCAT".TrustEngine.PKIX");
 785
 786     const KeyInfoResolver* inlineResolver = m_keyInfoResolver;
 787     if (!inlineResolver)
 788         inlineResolver = XMLToolingConfig::getConfig().getKeyInfoResolver();
 789     if (!inlineResolver) {
 790         log.error("unable to perform PKIX validation, no KeyInfoResolver available");
 791         return false;
 792     }
 793
 794     // Pull the certificate chain out of the signature.
 795     X509Credential* x509cred;
 796     auto_ptr<Credential> cred(inlineResolver->resolve(&sig,X509Credential::RESOLVE_CERTS|X509Credential::RESOLVE_CRLS));
 797     if (!cred.get() || !(x509cred=dynamic_cast<X509Credential*>(cred.get()))) {
 798         log.error("unable to perform PKIX validation, signature does not contain any certificates");
 799         return false;
 800     }
 801     const vector<XSECCryptoX509*>& certs = x509cred->getEntityCertificateChain();
 802     if (certs.empty()) {
 803         log.error("unable to perform PKIX validation, signature does not contain any certificates");
 804         return false;
 805     }
 806
 807     log.debug("validating signature using certificate from within the signature");
 808
 809     // Find and save off a pointer to the certificate that unlocks the object.
 810     // Most of the time, this will be the first one anyway.
 811     XSECCryptoX509* certEE=nullptr;
 812     SignatureValidator keyValidator;
 813     for (vector<XSECCryptoX509*>::const_iterator i=certs.begin(); !certEE && i!=certs.end(); ++i) {
 814         try {
 815             auto_ptr<XSECCryptoKey> key((*i)->clonePublicKey());
 816             keyValidator.setKey(key.get());
 817             keyValidator.validate(&sig);
 818             log.debug("signature verified with key inside signature, attempting certificate validation...");
 819             certEE=(*i);
 820         }
 821         catch (ValidationException& ex) {
 822             log.debug(ex.what());
 823         }
 824     }
 825
 826     if (!certEE) {
 827         log.debug("failed to verify signature with embedded certificates");
 828         return false;
 829     }
 830     else if (certEE->getProviderName()!=DSIGConstants::s_unicodeStrPROVOpenSSL) {
 831         log.error("only the OpenSSL XSEC provider is supported");
 832         return false;
 833     }
 834
 835     STACK_OF(X509)* untrusted=sk_X509_new_null();
 836     for (vector<XSECCryptoX509*>::const_iterator i=certs.begin(); i!=certs.end(); ++i)
 837         sk_X509_push(untrusted,static_cast<OpenSSLCryptoX509*>(*i)->getOpenSSLX509());
 838     const vector<XSECCryptoX509CRL*>& crls = x509cred->getCRLs();
 839     bool ret = validateWithCRLs(static_cast<OpenSSLCryptoX509*>(certEE)->getOpenSSLX509(), untrusted, credResolver, criteria, &crls);
 840     sk_X509_free(untrusted);
 841     return ret;
 842 }
 843
 844 bool AbstractPKIXTrustEngine::validate(
 845     const XMLCh* sigAlgorithm,
 846     const char* sig,
 847     KeyInfo* keyInfo,
 848     const char* in,
 849     unsigned int in_len,
 850     const CredentialResolver& credResolver,
 851     CredentialCriteria* criteria
 852     ) const
 853 {
 854 #ifdef _DEBUG
 855     NDC ndc("validate");
 856 #endif
 857     Category& log=Category::getInstance(XMLTOOLING_LOGCAT".TrustEngine.PKIX");
 858
 859     if (!keyInfo) {
 860         log.error("unable to perform PKIX validation, KeyInfo not present");
 861         return false;
 862     }
 863
 864     const KeyInfoResolver* inlineResolver = m_keyInfoResolver;
 865     if (!inlineResolver)
 866         inlineResolver = XMLToolingConfig::getConfig().getKeyInfoResolver();
 867     if (!inlineResolver) {
 868         log.error("unable to perform PKIX validation, no KeyInfoResolver available");
 869         return false;
 870     }
 871
 872     // Pull the certificate chain out of the signature.
 873     X509Credential* x509cred;
 874     auto_ptr<Credential> cred(inlineResolver->resolve(keyInfo,X509Credential::RESOLVE_CERTS));
 875     if (!cred.get() || !(x509cred=dynamic_cast<X509Credential*>(cred.get()))) {
 876         log.error("unable to perform PKIX validation, KeyInfo does not contain any certificates");
 877         return false;
 878     }
 879     const vector<XSECCryptoX509*>& certs = x509cred->getEntityCertificateChain();
 880     if (certs.empty()) {
 881         log.error("unable to perform PKIX validation, KeyInfo does not contain any certificates");
 882         return false;
 883     }
 884
 885     log.debug("validating signature using certificate from within KeyInfo");
 886
 887     // Find and save off a pointer to the certificate that unlocks the object.
 888     // Most of the time, this will be the first one anyway.
 889     XSECCryptoX509* certEE=nullptr;
 890     for (vector<XSECCryptoX509*>::const_iterator i=certs.begin(); !certEE && i!=certs.end(); ++i) {
 891         try {
 892             auto_ptr<XSECCryptoKey> key((*i)->clonePublicKey());
 893             if (Signature::verifyRawSignature(key.get(), sigAlgorithm, sig, in, in_len)) {
 894                 log.debug("signature verified with key inside signature, attempting certificate validation...");
 895                 certEE=(*i);
 896             }
 897         }
 898         catch (SignatureException& ex) {
 899             log.debug(ex.what());
 900         }
 901     }
 902
 903     if (!certEE) {
 904         log.debug("failed to verify signature with embedded certificates");
 905         return false;
 906     }
 907     else if (certEE->getProviderName()!=DSIGConstants::s_unicodeStrPROVOpenSSL) {
 908         log.error("only the OpenSSL XSEC provider is supported");
 909         return false;
 910     }
 911
 912     STACK_OF(X509)* untrusted=sk_X509_new_null();
 913     for (vector<XSECCryptoX509*>::const_iterator i=certs.begin(); i!=certs.end(); ++i)
 914         sk_X509_push(untrusted,static_cast<OpenSSLCryptoX509*>(*i)->getOpenSSLX509());
 915     const vector<XSECCryptoX509CRL*>& crls = x509cred->getCRLs();
 916     bool ret = validateWithCRLs(static_cast<OpenSSLCryptoX509*>(certEE)->getOpenSSLX509(), untrusted, credResolver, criteria, &crls);
 917     sk_X509_free(untrusted);
 918     return ret;
 919 }