git.oblomov.eu Git - wine/blob - dlls/crypt32/chain.c

   1 /*
   2  * Copyright 2006 Juan Lang
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  17  *
  18  */
  19 #include <stdarg.h>
  20 #define NONAMELESSUNION
  21 #include "windef.h"
  22 #include "winbase.h"
  23 #define CERT_CHAIN_PARA_HAS_EXTRA_FIELDS
  24 #define CERT_REVOCATION_PARA_HAS_EXTRA_FIELDS
  25 #include "wincrypt.h"
  26 #include "wine/debug.h"
  27 #include "wine/unicode.h"
  28 #include "crypt32_private.h"
  29
  30 WINE_DEFAULT_DEBUG_CHANNEL(crypt);
  31 WINE_DECLARE_DEBUG_CHANNEL(chain);
  32
  33 #define DEFAULT_CYCLE_MODULUS 7
  34
  35 static HCERTCHAINENGINE CRYPT_defaultChainEngine;
  36
  37 /* This represents a subset of a certificate chain engine:  it doesn't include
  38  * the "hOther" store described by MSDN, because I'm not sure how that's used.
  39  * It also doesn't include the "hTrust" store, because I don't yet implement
  40  * CTLs or complex certificate chains.
  41  */
  42 typedef struct _CertificateChainEngine
  43 {
  44     LONG       ref;
  45     HCERTSTORE hRoot;
  46     HCERTSTORE hWorld;
  47     DWORD      dwFlags;
  48     DWORD      dwUrlRetrievalTimeout;
  49     DWORD      MaximumCachedCertificates;
  50     DWORD      CycleDetectionModulus;
  51 } CertificateChainEngine, *PCertificateChainEngine;
  52
  53 static inline void CRYPT_AddStoresToCollection(HCERTSTORE collection,
  54  DWORD cStores, HCERTSTORE *stores)
  55 {
  56     DWORD i;
  57
  58     for (i = 0; i < cStores; i++)
  59         CertAddStoreToCollection(collection, stores[i], 0, 0);
  60 }
  61
  62 static inline void CRYPT_CloseStores(DWORD cStores, HCERTSTORE *stores)
  63 {
  64     DWORD i;
  65
  66     for (i = 0; i < cStores; i++)
  67         CertCloseStore(stores[i], 0);
  68 }
  69
  70 static const WCHAR rootW[] = { 'R','o','o','t',0 };
  71
  72 /* Finds cert in store by comparing the cert's hashes. */
  73 static PCCERT_CONTEXT CRYPT_FindCertInStore(HCERTSTORE store,
  74  PCCERT_CONTEXT cert)
  75 {
  76     PCCERT_CONTEXT matching = NULL;
  77     BYTE hash[20];
  78     DWORD size = sizeof(hash);
  79
  80     if (CertGetCertificateContextProperty(cert, CERT_HASH_PROP_ID, hash, &size))
  81     {
  82         CRYPT_HASH_BLOB blob = { sizeof(hash), hash };
  83
  84         matching = CertFindCertificateInStore(store, cert->dwCertEncodingType,
  85          0, CERT_FIND_SHA1_HASH, &blob, NULL);
  86     }
  87     return matching;
  88 }
  89
  90 static BOOL CRYPT_CheckRestrictedRoot(HCERTSTORE store)
  91 {
  92     BOOL ret = TRUE;
  93
  94     if (store)
  95     {
  96         HCERTSTORE rootStore = CertOpenSystemStoreW(0, rootW);
  97         PCCERT_CONTEXT cert = NULL, check;
  98
  99         do {
 100             cert = CertEnumCertificatesInStore(store, cert);
 101             if (cert)
 102             {
 103                 if (!(check = CRYPT_FindCertInStore(rootStore, cert)))
 104                     ret = FALSE;
 105                 else
 106                     CertFreeCertificateContext(check);
 107             }
 108         } while (ret && cert);
 109         if (cert)
 110             CertFreeCertificateContext(cert);
 111         CertCloseStore(rootStore, 0);
 112     }
 113     return ret;
 114 }
 115
 116 HCERTCHAINENGINE CRYPT_CreateChainEngine(HCERTSTORE root,
 117  PCERT_CHAIN_ENGINE_CONFIG pConfig)
 118 {
 119     static const WCHAR caW[] = { 'C','A',0 };
 120     static const WCHAR myW[] = { 'M','y',0 };
 121     static const WCHAR trustW[] = { 'T','r','u','s','t',0 };
 122     PCertificateChainEngine engine =
 123      CryptMemAlloc(sizeof(CertificateChainEngine));
 124
 125     if (engine)
 126     {
 127         HCERTSTORE worldStores[4];
 128
 129         engine->ref = 1;
 130         engine->hRoot = root;
 131         engine->hWorld = CertOpenStore(CERT_STORE_PROV_COLLECTION, 0, 0,
 132          CERT_STORE_CREATE_NEW_FLAG, NULL);
 133         worldStores[0] = CertDuplicateStore(engine->hRoot);
 134         worldStores[1] = CertOpenSystemStoreW(0, caW);
 135         worldStores[2] = CertOpenSystemStoreW(0, myW);
 136         worldStores[3] = CertOpenSystemStoreW(0, trustW);
 137         CRYPT_AddStoresToCollection(engine->hWorld,
 138          sizeof(worldStores) / sizeof(worldStores[0]), worldStores);
 139         CRYPT_AddStoresToCollection(engine->hWorld,
 140          pConfig->cAdditionalStore, pConfig->rghAdditionalStore);
 141         CRYPT_CloseStores(sizeof(worldStores) / sizeof(worldStores[0]),
 142          worldStores);
 143         engine->dwFlags = pConfig->dwFlags;
 144         engine->dwUrlRetrievalTimeout = pConfig->dwUrlRetrievalTimeout;
 145         engine->MaximumCachedCertificates =
 146          pConfig->MaximumCachedCertificates;
 147         if (pConfig->CycleDetectionModulus)
 148             engine->CycleDetectionModulus = pConfig->CycleDetectionModulus;
 149         else
 150             engine->CycleDetectionModulus = DEFAULT_CYCLE_MODULUS;
 151     }
 152     return engine;
 153 }
 154
 155 BOOL WINAPI CertCreateCertificateChainEngine(PCERT_CHAIN_ENGINE_CONFIG pConfig,
 156  HCERTCHAINENGINE *phChainEngine)
 157 {
 158     BOOL ret;
 159
 160     TRACE("(%p, %p)\n", pConfig, phChainEngine);
 161
 162     if (pConfig->cbSize != sizeof(*pConfig))
 163     {
 164         SetLastError(E_INVALIDARG);
 165         return FALSE;
 166     }
 167     *phChainEngine = NULL;
 168     ret = CRYPT_CheckRestrictedRoot(pConfig->hRestrictedRoot);
 169     if (ret)
 170     {
 171         HCERTSTORE root;
 172         HCERTCHAINENGINE engine;
 173
 174         if (pConfig->hRestrictedRoot)
 175             root = CertDuplicateStore(pConfig->hRestrictedRoot);
 176         else
 177             root = CertOpenSystemStoreW(0, rootW);
 178         engine = CRYPT_CreateChainEngine(root, pConfig);
 179         if (engine)
 180         {
 181             *phChainEngine = engine;
 182             ret = TRUE;
 183         }
 184         else
 185             ret = FALSE;
 186     }
 187     return ret;
 188 }
 189
 190 VOID WINAPI CertFreeCertificateChainEngine(HCERTCHAINENGINE hChainEngine)
 191 {
 192     PCertificateChainEngine engine = (PCertificateChainEngine)hChainEngine;
 193
 194     TRACE("(%p)\n", hChainEngine);
 195
 196     if (engine && InterlockedDecrement(&engine->ref) == 0)
 197     {
 198         CertCloseStore(engine->hWorld, 0);
 199         CertCloseStore(engine->hRoot, 0);
 200         CryptMemFree(engine);
 201     }
 202 }
 203
 204 static HCERTCHAINENGINE CRYPT_GetDefaultChainEngine(void)
 205 {
 206     if (!CRYPT_defaultChainEngine)
 207     {
 208         CERT_CHAIN_ENGINE_CONFIG config = { 0 };
 209         HCERTCHAINENGINE engine;
 210
 211         config.cbSize = sizeof(config);
 212         CertCreateCertificateChainEngine(&config, &engine);
 213         InterlockedCompareExchangePointer(&CRYPT_defaultChainEngine, engine,
 214          NULL);
 215         if (CRYPT_defaultChainEngine != engine)
 216             CertFreeCertificateChainEngine(engine);
 217     }
 218     return CRYPT_defaultChainEngine;
 219 }
 220
 221 void default_chain_engine_free(void)
 222 {
 223     CertFreeCertificateChainEngine(CRYPT_defaultChainEngine);
 224 }
 225
 226 typedef struct _CertificateChain
 227 {
 228     CERT_CHAIN_CONTEXT context;
 229     HCERTSTORE world;
 230     LONG ref;
 231 } CertificateChain, *PCertificateChain;
 232
 233 static BOOL CRYPT_IsCertificateSelfSigned(PCCERT_CONTEXT cert)
 234 {
 235     PCERT_EXTENSION ext;
 236     DWORD size;
 237     BOOL ret;
 238
 239     if ((ext = CertFindExtension(szOID_AUTHORITY_KEY_IDENTIFIER2,
 240      cert->pCertInfo->cExtension, cert->pCertInfo->rgExtension)))
 241     {
 242         CERT_AUTHORITY_KEY_ID2_INFO *info;
 243
 244         ret = CryptDecodeObjectEx(cert->dwCertEncodingType,
 245          X509_AUTHORITY_KEY_ID2, ext->Value.pbData, ext->Value.cbData,
 246          CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG, NULL,
 247          &info, &size);
 248         if (ret)
 249         {
 250             if (info->AuthorityCertIssuer.cAltEntry &&
 251              info->AuthorityCertSerialNumber.cbData)
 252             {
 253                 PCERT_ALT_NAME_ENTRY directoryName = NULL;
 254                 DWORD i;
 255
 256                 for (i = 0; !directoryName &&
 257                  i < info->AuthorityCertIssuer.cAltEntry; i++)
 258                     if (info->AuthorityCertIssuer.rgAltEntry[i].dwAltNameChoice
 259                      == CERT_ALT_NAME_DIRECTORY_NAME)
 260                         directoryName =
 261                          &info->AuthorityCertIssuer.rgAltEntry[i];
 262                 if (directoryName)
 263                 {
 264                     ret = CertCompareCertificateName(cert->dwCertEncodingType,
 265                      &directoryName->u.DirectoryName, &cert->pCertInfo->Issuer)
 266                      && CertCompareIntegerBlob(&info->AuthorityCertSerialNumber,
 267                      &cert->pCertInfo->SerialNumber);
 268                 }
 269                 else
 270                 {
 271                     FIXME("no supported name type in authority key id2\n");
 272                     ret = FALSE;
 273                 }
 274             }
 275             else if (info->KeyId.cbData)
 276             {
 277                 ret = CertGetCertificateContextProperty(cert,
 278                  CERT_KEY_IDENTIFIER_PROP_ID, NULL, &size);
 279                 if (ret && size == info->KeyId.cbData)
 280                 {
 281                     LPBYTE buf = CryptMemAlloc(size);
 282
 283                     if (buf)
 284                     {
 285                         CertGetCertificateContextProperty(cert,
 286                          CERT_KEY_IDENTIFIER_PROP_ID, buf, &size);
 287                         ret = !memcmp(buf, info->KeyId.pbData, size);
 288                         CryptMemFree(buf);
 289                     }
 290                 }
 291                 else
 292                     ret = FALSE;
 293             }
 294             LocalFree(info);
 295         }
 296     }
 297     else if ((ext = CertFindExtension(szOID_AUTHORITY_KEY_IDENTIFIER,
 298      cert->pCertInfo->cExtension, cert->pCertInfo->rgExtension)))
 299     {
 300         CERT_AUTHORITY_KEY_ID_INFO *info;
 301
 302         ret = CryptDecodeObjectEx(cert->dwCertEncodingType,
 303          X509_AUTHORITY_KEY_ID, ext->Value.pbData, ext->Value.cbData,
 304          CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG, NULL,
 305          &info, &size);
 306         if (ret)
 307         {
 308             if (info->CertIssuer.cbData && info->CertSerialNumber.cbData)
 309             {
 310                 ret = CertCompareCertificateName(cert->dwCertEncodingType,
 311                  &info->CertIssuer, &cert->pCertInfo->Issuer) &&
 312                  CertCompareIntegerBlob(&info->CertSerialNumber,
 313                  &cert->pCertInfo->SerialNumber);
 314             }
 315             else if (info->KeyId.cbData)
 316             {
 317                 ret = CertGetCertificateContextProperty(cert,
 318                  CERT_KEY_IDENTIFIER_PROP_ID, NULL, &size);
 319                 if (ret && size == info->KeyId.cbData)
 320                 {
 321                     LPBYTE buf = CryptMemAlloc(size);
 322
 323                     if (buf)
 324                     {
 325                         CertGetCertificateContextProperty(cert,
 326                          CERT_KEY_IDENTIFIER_PROP_ID, buf, &size);
 327                         ret = !memcmp(buf, info->KeyId.pbData, size);
 328                         CryptMemFree(buf);
 329                     }
 330                     else
 331                         ret = FALSE;
 332                 }
 333                 else
 334                     ret = FALSE;
 335             }
 336             else
 337                 ret = FALSE;
 338             LocalFree(info);
 339         }
 340     }
 341     else
 342         ret = CertCompareCertificateName(cert->dwCertEncodingType,
 343          &cert->pCertInfo->Subject, &cert->pCertInfo->Issuer);
 344     return ret;
 345 }
 346
 347 static void CRYPT_FreeChainElement(PCERT_CHAIN_ELEMENT element)
 348 {
 349     CertFreeCertificateContext(element->pCertContext);
 350     CryptMemFree(element);
 351 }
 352
 353 static void CRYPT_CheckSimpleChainForCycles(PCERT_SIMPLE_CHAIN chain)
 354 {
 355     DWORD i, j, cyclicCertIndex = 0;
 356
 357     /* O(n^2) - I don't think there's a faster way */
 358     for (i = 0; !cyclicCertIndex && i < chain->cElement; i++)
 359         for (j = i + 1; !cyclicCertIndex && j < chain->cElement; j++)
 360             if (CertCompareCertificate(X509_ASN_ENCODING,
 361              chain->rgpElement[i]->pCertContext->pCertInfo,
 362              chain->rgpElement[j]->pCertContext->pCertInfo))
 363                 cyclicCertIndex = j;
 364     if (cyclicCertIndex)
 365     {
 366         chain->rgpElement[cyclicCertIndex]->TrustStatus.dwErrorStatus
 367          |= CERT_TRUST_IS_CYCLIC | CERT_TRUST_INVALID_BASIC_CONSTRAINTS;
 368         /* Release remaining certs */
 369         for (i = cyclicCertIndex + 1; i < chain->cElement; i++)
 370             CRYPT_FreeChainElement(chain->rgpElement[i]);
 371         /* Truncate chain */
 372         chain->cElement = cyclicCertIndex + 1;
 373     }
 374 }
 375
 376 /* Checks whether the chain is cyclic by examining the last element's status */
 377 static inline BOOL CRYPT_IsSimpleChainCyclic(const CERT_SIMPLE_CHAIN *chain)
 378 {
 379     if (chain->cElement)
 380         return chain->rgpElement[chain->cElement - 1]->TrustStatus.dwErrorStatus
 381          & CERT_TRUST_IS_CYCLIC;
 382     else
 383         return FALSE;
 384 }
 385
 386 static inline void CRYPT_CombineTrustStatus(CERT_TRUST_STATUS *chainStatus,
 387  const CERT_TRUST_STATUS *elementStatus)
 388 {
 389     /* Any error that applies to an element also applies to a chain.. */
 390     chainStatus->dwErrorStatus |= elementStatus->dwErrorStatus;
 391     /* but the bottom nibble of an element's info status doesn't apply to the
 392      * chain.
 393      */
 394     chainStatus->dwInfoStatus |= (elementStatus->dwInfoStatus & 0xfffffff0);
 395 }
 396
 397 static BOOL CRYPT_AddCertToSimpleChain(const CertificateChainEngine *engine,
 398  PCERT_SIMPLE_CHAIN chain, PCCERT_CONTEXT cert, DWORD subjectInfoStatus)
 399 {
 400     BOOL ret = FALSE;
 401     PCERT_CHAIN_ELEMENT element = CryptMemAlloc(sizeof(CERT_CHAIN_ELEMENT));
 402
 403     if (element)
 404     {
 405         if (!chain->cElement)
 406             chain->rgpElement = CryptMemAlloc(sizeof(PCERT_CHAIN_ELEMENT));
 407         else
 408             chain->rgpElement = CryptMemRealloc(chain->rgpElement,
 409              (chain->cElement + 1) * sizeof(PCERT_CHAIN_ELEMENT));
 410         if (chain->rgpElement)
 411         {
 412             chain->rgpElement[chain->cElement++] = element;
 413             memset(element, 0, sizeof(CERT_CHAIN_ELEMENT));
 414             element->cbSize = sizeof(CERT_CHAIN_ELEMENT);
 415             element->pCertContext = CertDuplicateCertificateContext(cert);
 416             if (chain->cElement > 1)
 417                 chain->rgpElement[chain->cElement - 2]->TrustStatus.dwInfoStatus
 418                  = subjectInfoStatus;
 419             /* FIXME: initialize the rest of element */
 420             if (!(chain->cElement % engine->CycleDetectionModulus))
 421             {
 422                 CRYPT_CheckSimpleChainForCycles(chain);
 423                 /* Reinitialize the element pointer in case the chain is
 424                  * cyclic, in which case the chain is truncated.
 425                  */
 426                 element = chain->rgpElement[chain->cElement - 1];
 427             }
 428             CRYPT_CombineTrustStatus(&chain->TrustStatus,
 429              &element->TrustStatus);
 430             ret = TRUE;
 431         }
 432         else
 433             CryptMemFree(element);
 434     }
 435     return ret;
 436 }
 437
 438 static void CRYPT_FreeSimpleChain(PCERT_SIMPLE_CHAIN chain)
 439 {
 440     DWORD i;
 441
 442     for (i = 0; i < chain->cElement; i++)
 443         CRYPT_FreeChainElement(chain->rgpElement[i]);
 444     CryptMemFree(chain->rgpElement);
 445     CryptMemFree(chain);
 446 }
 447
 448 static void CRYPT_CheckTrustedStatus(HCERTSTORE hRoot,
 449  PCERT_CHAIN_ELEMENT rootElement)
 450 {
 451     PCCERT_CONTEXT trustedRoot = CRYPT_FindCertInStore(hRoot,
 452      rootElement->pCertContext);
 453
 454     if (!trustedRoot)
 455         rootElement->TrustStatus.dwErrorStatus |=
 456          CERT_TRUST_IS_UNTRUSTED_ROOT;
 457     else
 458         CertFreeCertificateContext(trustedRoot);
 459 }
 460
 461 static void CRYPT_CheckRootCert(HCERTCHAINENGINE hRoot,
 462  PCERT_CHAIN_ELEMENT rootElement)
 463 {
 464     PCCERT_CONTEXT root = rootElement->pCertContext;
 465
 466     if (!CryptVerifyCertificateSignatureEx(0, root->dwCertEncodingType,
 467      CRYPT_VERIFY_CERT_SIGN_SUBJECT_CERT, (void *)root,
 468      CRYPT_VERIFY_CERT_SIGN_ISSUER_CERT, (void *)root, 0, NULL))
 469     {
 470         TRACE_(chain)("Last certificate's signature is invalid\n");
 471         rootElement->TrustStatus.dwErrorStatus |=
 472          CERT_TRUST_IS_NOT_SIGNATURE_VALID;
 473     }
 474     CRYPT_CheckTrustedStatus(hRoot, rootElement);
 475 }
 476
 477 /* Decodes a cert's basic constraints extension (either szOID_BASIC_CONSTRAINTS
 478  * or szOID_BASIC_CONSTRAINTS2, whichever is present) into a
 479  * CERT_BASIC_CONSTRAINTS2_INFO.  If it neither extension is present, sets
 480  * constraints->fCA to defaultIfNotSpecified.
 481  * Returns FALSE if the extension is present but couldn't be decoded.
 482  */
 483 static BOOL CRYPT_DecodeBasicConstraints(PCCERT_CONTEXT cert,
 484  CERT_BASIC_CONSTRAINTS2_INFO *constraints, BOOL defaultIfNotSpecified)
 485 {
 486     BOOL ret = TRUE;
 487     PCERT_EXTENSION ext = CertFindExtension(szOID_BASIC_CONSTRAINTS,
 488      cert->pCertInfo->cExtension, cert->pCertInfo->rgExtension);
 489
 490     constraints->fPathLenConstraint = FALSE;
 491     if (ext)
 492     {
 493         CERT_BASIC_CONSTRAINTS_INFO *info;
 494         DWORD size = 0;
 495
 496         ret = CryptDecodeObjectEx(X509_ASN_ENCODING, szOID_BASIC_CONSTRAINTS,
 497          ext->Value.pbData, ext->Value.cbData, CRYPT_DECODE_ALLOC_FLAG,
 498          NULL, &info, &size);
 499         if (ret)
 500         {
 501             if (info->SubjectType.cbData == 1)
 502                 constraints->fCA =
 503                  info->SubjectType.pbData[0] & CERT_CA_SUBJECT_FLAG;
 504             LocalFree(info);
 505         }
 506     }
 507     else
 508     {
 509         ext = CertFindExtension(szOID_BASIC_CONSTRAINTS2,
 510          cert->pCertInfo->cExtension, cert->pCertInfo->rgExtension);
 511         if (ext)
 512         {
 513             DWORD size = sizeof(CERT_BASIC_CONSTRAINTS2_INFO);
 514
 515             ret = CryptDecodeObjectEx(X509_ASN_ENCODING,
 516              szOID_BASIC_CONSTRAINTS2, ext->Value.pbData, ext->Value.cbData,
 517              0, NULL, constraints, &size);
 518         }
 519         else
 520             constraints->fCA = defaultIfNotSpecified;
 521     }
 522     return ret;
 523 }
 524
 525 /* Checks element's basic constraints to see if it can act as a CA, with
 526  * remainingCAs CAs left in this chain.  In general, a cert must include the
 527  * basic constraints extension, with the CA flag asserted, in order to be
 528  * allowed to be a CA.  A V1 or V2 cert, which has no extensions, is also
 529  * allowed to be a CA if it's installed locally (in the engine's world store.)
 530  * This matches the expected usage in RFC 5280, section 4.2.1.9:  a conforming
 531  * CA MUST include the basic constraints extension in all certificates that are
 532  * used to validate digital signatures on certificates.  It also matches
 533  * section 6.1.4(k): "If a certificate is a v1 or v2 certificate, then the
 534  * application MUST either verify that the certificate is a CA certificate
 535  * through out-of-band means or reject the certificate." Rejecting the
 536  * certificate prohibits a large number of commonly used certificates, so
 537  * accepting locally installed ones is a compromise.
 538  * Root certificates are also allowed to be CAs even without a basic
 539  * constraints extension.  This is implied by RFC 5280, section 6.1:  the
 540  * root of a certificate chain's only requirement is that it was used to issue
 541  * the next certificate in the chain.
 542  * Updates chainConstraints with the element's constraints, if:
 543  * 1. chainConstraints doesn't have a path length constraint, or
 544  * 2. element's path length constraint is smaller than chainConstraints's
 545  * Sets *pathLengthConstraintViolated to TRUE if a path length violation
 546  * occurs.
 547  * Returns TRUE if the element can be a CA, and the length of the remaining
 548  * chain is valid.
 549  */
 550 static BOOL CRYPT_CheckBasicConstraintsForCA(PCertificateChainEngine engine,
 551  PCCERT_CONTEXT cert, CERT_BASIC_CONSTRAINTS2_INFO *chainConstraints,
 552  DWORD remainingCAs, BOOL isRoot, BOOL *pathLengthConstraintViolated)
 553 {
 554     BOOL validBasicConstraints, implicitCA = FALSE;
 555     CERT_BASIC_CONSTRAINTS2_INFO constraints;
 556
 557     if (isRoot)
 558         implicitCA = TRUE;
 559     else if (cert->pCertInfo->dwVersion == CERT_V1 ||
 560      cert->pCertInfo->dwVersion == CERT_V2)
 561     {
 562         BYTE hash[20];
 563         DWORD size = sizeof(hash);
 564
 565         if (CertGetCertificateContextProperty(cert, CERT_HASH_PROP_ID,
 566          hash, &size))
 567         {
 568             CRYPT_HASH_BLOB blob = { sizeof(hash), hash };
 569             PCCERT_CONTEXT localCert = CertFindCertificateInStore(
 570              engine->hWorld, cert->dwCertEncodingType, 0, CERT_FIND_SHA1_HASH,
 571              &blob, NULL);
 572
 573             if (localCert)
 574             {
 575                 CertFreeCertificateContext(localCert);
 576                 implicitCA = TRUE;
 577             }
 578         }
 579     }
 580     if ((validBasicConstraints = CRYPT_DecodeBasicConstraints(cert,
 581      &constraints, implicitCA)))
 582     {
 583         chainConstraints->fCA = constraints.fCA;
 584         if (!constraints.fCA)
 585         {
 586             TRACE_(chain)("chain element %d can't be a CA\n", remainingCAs + 1);
 587             validBasicConstraints = FALSE;
 588         }
 589         else if (constraints.fPathLenConstraint)
 590         {
 591             /* If the element has path length constraints, they apply to the
 592              * entire remaining chain.
 593              */
 594             if (!chainConstraints->fPathLenConstraint ||
 595              constraints.dwPathLenConstraint <
 596              chainConstraints->dwPathLenConstraint)
 597             {
 598                 TRACE_(chain)("setting path length constraint to %d\n",
 599                  chainConstraints->dwPathLenConstraint);
 600                 chainConstraints->fPathLenConstraint = TRUE;
 601                 chainConstraints->dwPathLenConstraint =
 602                  constraints.dwPathLenConstraint;
 603             }
 604         }
 605     }
 606     if (chainConstraints->fPathLenConstraint &&
 607      remainingCAs > chainConstraints->dwPathLenConstraint)
 608     {
 609         TRACE_(chain)("remaining CAs %d exceed max path length %d\n",
 610          remainingCAs, chainConstraints->dwPathLenConstraint);
 611         validBasicConstraints = FALSE;
 612         *pathLengthConstraintViolated = TRUE;
 613     }
 614     return validBasicConstraints;
 615 }
 616
 617 static BOOL domain_name_matches(LPCWSTR constraint, LPCWSTR name)
 618 {
 619     BOOL match;
 620
 621     /* RFC 5280, section 4.2.1.10:
 622      * "For URIs, the constraint applies to the host part of the name...
 623      *  When the constraint begins with a period, it MAY be expanded with one
 624      *  or more labels.  That is, the constraint ".example.com" is satisfied by
 625      *  both host.example.com and my.host.example.com.  However, the constraint
 626      *  ".example.com" is not satisfied by "example.com".  When the constraint
 627      *  does not begin with a period, it specifies a host."
 628      * and for email addresses,
 629      * "To indicate all Internet mail addresses on a particular host, the
 630      *  constraint is specified as the host name.  For example, the constraint
 631      *  "example.com" is satisfied by any mail address at the host
 632      *  "example.com".  To specify any address within a domain, the constraint
 633      *  is specified with a leading period (as with URIs)."
 634      */
 635     if (constraint[0] == '.')
 636     {
 637         /* Must be strictly greater than, a name can't begin with '.' */
 638         if (lstrlenW(name) > lstrlenW(constraint))
 639             match = !lstrcmpiW(name + lstrlenW(name) - lstrlenW(constraint),
 640              constraint);
 641         else
 642         {
 643             /* name is too short, no match */
 644             match = FALSE;
 645         }
 646     }
 647     else
 648         match = !lstrcmpiW(name, constraint);
 649      return match;
 650 }
 651
 652 static BOOL url_matches(LPCWSTR constraint, LPCWSTR name,
 653  DWORD *trustErrorStatus)
 654 {
 655     BOOL match = FALSE;
 656
 657     TRACE("%s, %s\n", debugstr_w(constraint), debugstr_w(name));
 658
 659     if (!constraint)
 660         *trustErrorStatus |= CERT_TRUST_INVALID_NAME_CONSTRAINTS;
 661     else if (!name)
 662         ; /* no match */
 663     else
 664     {
 665         LPCWSTR colon, authority_end, at, hostname = NULL;
 666         /* The maximum length for a hostname is 254 in the DNS, see RFC 1034 */
 667         WCHAR hostname_buf[255];
 668
 669         /* RFC 5280: only the hostname portion of the URL is compared.  From
 670          * section 4.2.1.10:
 671          * "For URIs, the constraint applies to the host part of the name.
 672          *  The constraint MUST be specified as a fully qualified domain name
 673          *  and MAY specify a host or a domain."
 674          * The format for URIs is in RFC 2396.
 675          *
 676          * First, remove any scheme that's present. */
 677         colon = strchrW(name, ':');
 678         if (colon && *(colon + 1) == '/' && *(colon + 2) == '/')
 679             name = colon + 3;
 680         /* Next, find the end of the authority component.  (The authority is
 681          * generally just the hostname, but it may contain a username or a port.
 682          * Those are removed next.)
 683          */
 684         authority_end = strchrW(name, '/');
 685         if (!authority_end)
 686             authority_end = strchrW(name, '?');
 687         if (!authority_end)
 688             authority_end = name + strlenW(name);
 689         /* Remove any port number from the authority */
 690         for (colon = authority_end; colon >= name && *colon != ':'; colon--)
 691             ;
 692         if (*colon == ':')
 693             authority_end = colon;
 694         /* Remove any username from the authority */
 695         if ((at = strchrW(name, '@')))
 696             name = at;
 697         /* Ignore any path or query portion of the URL. */
 698         if (*authority_end)
 699         {
 700             if (authority_end - name < sizeof(hostname_buf) /
 701              sizeof(hostname_buf[0]))
 702             {
 703                 memcpy(hostname_buf, name,
 704                  (authority_end - name) * sizeof(WCHAR));
 705                 hostname_buf[authority_end - name] = 0;
 706                 hostname = hostname_buf;
 707             }
 708             /* else: Hostname is too long, not a match */
 709         }
 710         else
 711             hostname = name;
 712         if (hostname)
 713             match = domain_name_matches(constraint, hostname);
 714     }
 715     return match;
 716 }
 717
 718 static BOOL rfc822_name_matches(LPCWSTR constraint, LPCWSTR name,
 719  DWORD *trustErrorStatus)
 720 {
 721     BOOL match = FALSE;
 722     LPCWSTR at;
 723
 724     TRACE("%s, %s\n", debugstr_w(constraint), debugstr_w(name));
 725
 726     if (!constraint)
 727         *trustErrorStatus |= CERT_TRUST_INVALID_NAME_CONSTRAINTS;
 728     else if (!name)
 729         ; /* no match */
 730     else if (strchrW(constraint, '@'))
 731         match = !lstrcmpiW(constraint, name);
 732     else
 733     {
 734         if ((at = strchrW(name, '@')))
 735             match = domain_name_matches(constraint, at + 1);
 736         else
 737             match = !lstrcmpiW(constraint, name);
 738     }
 739     return match;
 740 }
 741
 742 static BOOL dns_name_matches(LPCWSTR constraint, LPCWSTR name,
 743  DWORD *trustErrorStatus)
 744 {
 745     BOOL match = FALSE;
 746
 747     TRACE("%s, %s\n", debugstr_w(constraint), debugstr_w(name));
 748
 749     if (!constraint)
 750         *trustErrorStatus |= CERT_TRUST_INVALID_NAME_CONSTRAINTS;
 751     else if (!name)
 752         ; /* no match */
 753     /* RFC 5280, section 4.2.1.10:
 754      * "DNS name restrictions are expressed as host.example.com.  Any DNS name
 755      *  that can be constructed by simply adding zero or more labels to the
 756      *  left-hand side of the name satisfies the name constraint.  For example,
 757      *  www.host.example.com would satisfy the constraint but host1.example.com
 758      *  would not."
 759      */
 760     else if (lstrlenW(name) == lstrlenW(constraint))
 761         match = !lstrcmpiW(name, constraint);
 762     else if (lstrlenW(name) > lstrlenW(constraint))
 763     {
 764         match = !lstrcmpiW(name + lstrlenW(name) - lstrlenW(constraint),
 765          constraint);
 766         if (match)
 767         {
 768             BOOL dot = FALSE;
 769             LPCWSTR ptr;
 770
 771             /* This only matches if name is a subdomain of constraint, i.e.
 772              * there's a '.' between the beginning of the name and the
 773              * matching portion of the name.
 774              */
 775             for (ptr = name + lstrlenW(name) - lstrlenW(constraint);
 776              !dot && ptr >= name; ptr--)
 777                 if (*ptr == '.')
 778                     dot = TRUE;
 779             match = dot;
 780         }
 781     }
 782     /* else:  name is too short, no match */
 783
 784     return match;
 785 }
 786
 787 static BOOL ip_address_matches(const CRYPT_DATA_BLOB *constraint,
 788  const CRYPT_DATA_BLOB *name, DWORD *trustErrorStatus)
 789 {
 790     BOOL match = FALSE;
 791
 792     TRACE("(%d, %p), (%d, %p)\n", constraint->cbData, constraint->pbData,
 793      name->cbData, name->pbData);
 794
 795     /* RFC5280, section 4.2.1.10, iPAddress syntax: either 8 or 32 bytes, for
 796      * IPv4 or IPv6 addresses, respectively.
 797      */
 798     if (constraint->cbData != sizeof(DWORD) * 2 && constraint->cbData != 32)
 799         *trustErrorStatus |= CERT_TRUST_INVALID_NAME_CONSTRAINTS;
 800     else if (name->cbData == sizeof(DWORD) &&
 801      constraint->cbData == sizeof(DWORD) * 2)
 802     {
 803         DWORD subnet, mask, addr;
 804
 805         memcpy(&subnet, constraint->pbData, sizeof(subnet));
 806         memcpy(&mask, constraint->pbData + sizeof(subnet), sizeof(mask));
 807         memcpy(&addr, name->pbData, sizeof(addr));
 808         /* These are really in big-endian order, but for equality matching we
 809          * don't need to swap to host order
 810          */
 811         match = (subnet & mask) == (addr & mask);
 812     }
 813     else if (name->cbData == 16 && constraint->cbData == 32)
 814     {
 815         const BYTE *subnet, *mask, *addr;
 816         DWORD i;
 817
 818         subnet = constraint->pbData;
 819         mask = constraint->pbData + 16;
 820         addr = name->pbData;
 821         match = TRUE;
 822         for (i = 0; match && i < 16; i++)
 823             if ((subnet[i] & mask[i]) != (addr[i] & mask[i]))
 824                 match = FALSE;
 825     }
 826     /* else: name is wrong size, no match */
 827
 828     return match;
 829 }
 830
 831 static BOOL directory_name_matches(const CERT_NAME_BLOB *constraint,
 832  const CERT_NAME_BLOB *name)
 833 {
 834     CERT_NAME_INFO *constraintName;
 835     DWORD size;
 836     BOOL match = FALSE;
 837
 838     if (CryptDecodeObjectEx(X509_ASN_ENCODING, X509_NAME, constraint->pbData,
 839      constraint->cbData, CRYPT_DECODE_ALLOC_FLAG, NULL, &constraintName, &size))
 840     {
 841         DWORD i;
 842
 843         match = TRUE;
 844         for (i = 0; match && i < constraintName->cRDN; i++)
 845             match = CertIsRDNAttrsInCertificateName(X509_ASN_ENCODING,
 846              CERT_CASE_INSENSITIVE_IS_RDN_ATTRS_FLAG,
 847              (CERT_NAME_BLOB *)name, &constraintName->rgRDN[i]);
 848         LocalFree(constraintName);
 849     }
 850     return match;
 851 }
 852
 853 static BOOL alt_name_matches(const CERT_ALT_NAME_ENTRY *name,
 854  const CERT_ALT_NAME_ENTRY *constraint, DWORD *trustErrorStatus, BOOL *present)
 855 {
 856     BOOL match = FALSE;
 857
 858     if (name->dwAltNameChoice == constraint->dwAltNameChoice)
 859     {
 860         if (present)
 861             *present = TRUE;
 862         switch (constraint->dwAltNameChoice)
 863         {
 864         case CERT_ALT_NAME_RFC822_NAME:
 865             match = rfc822_name_matches(constraint->u.pwszURL,
 866              name->u.pwszURL, trustErrorStatus);
 867             break;
 868         case CERT_ALT_NAME_DNS_NAME:
 869             match = dns_name_matches(constraint->u.pwszURL,
 870              name->u.pwszURL, trustErrorStatus);
 871             break;
 872         case CERT_ALT_NAME_URL:
 873             match = url_matches(constraint->u.pwszURL,
 874              name->u.pwszURL, trustErrorStatus);
 875             break;
 876         case CERT_ALT_NAME_IP_ADDRESS:
 877             match = ip_address_matches(&constraint->u.IPAddress,
 878              &name->u.IPAddress, trustErrorStatus);
 879             break;
 880         case CERT_ALT_NAME_DIRECTORY_NAME:
 881             match = directory_name_matches(&constraint->u.DirectoryName,
 882              &name->u.DirectoryName);
 883             break;
 884         default:
 885             ERR("name choice %d unsupported in this context\n",
 886              constraint->dwAltNameChoice);
 887             *trustErrorStatus |=
 888              CERT_TRUST_HAS_NOT_SUPPORTED_NAME_CONSTRAINT;
 889         }
 890     }
 891     else if (present)
 892         *present = FALSE;
 893     return match;
 894 }
 895
 896 static BOOL alt_name_matches_excluded_name(const CERT_ALT_NAME_ENTRY *name,
 897  const CERT_NAME_CONSTRAINTS_INFO *nameConstraints, DWORD *trustErrorStatus)
 898 {
 899     DWORD i;
 900     BOOL match = FALSE;
 901
 902     for (i = 0; !match && i < nameConstraints->cExcludedSubtree; i++)
 903         match = alt_name_matches(name,
 904          &nameConstraints->rgExcludedSubtree[i].Base, trustErrorStatus, NULL);
 905     return match;
 906 }
 907
 908 static BOOL alt_name_matches_permitted_name(const CERT_ALT_NAME_ENTRY *name,
 909  const CERT_NAME_CONSTRAINTS_INFO *nameConstraints, DWORD *trustErrorStatus,
 910  BOOL *present)
 911 {
 912     DWORD i;
 913     BOOL match = FALSE;
 914
 915     for (i = 0; !match && i < nameConstraints->cPermittedSubtree; i++)
 916         match = alt_name_matches(name,
 917          &nameConstraints->rgPermittedSubtree[i].Base, trustErrorStatus,
 918          present);
 919     return match;
 920 }
 921
 922 static inline PCERT_EXTENSION get_subject_alt_name_ext(const CERT_INFO *cert)
 923 {
 924     PCERT_EXTENSION ext;
 925
 926     ext = CertFindExtension(szOID_SUBJECT_ALT_NAME2,
 927      cert->cExtension, cert->rgExtension);
 928     if (!ext)
 929         ext = CertFindExtension(szOID_SUBJECT_ALT_NAME,
 930          cert->cExtension, cert->rgExtension);
 931     return ext;
 932 }
 933
 934 static void compare_alt_name_with_constraints(const CERT_EXTENSION *altNameExt,
 935  const CERT_NAME_CONSTRAINTS_INFO *nameConstraints, DWORD *trustErrorStatus)
 936 {
 937     CERT_ALT_NAME_INFO *subjectAltName;
 938     DWORD size;
 939
 940     if (CryptDecodeObjectEx(X509_ASN_ENCODING, X509_ALTERNATE_NAME,
 941      altNameExt->Value.pbData, altNameExt->Value.cbData,
 942      CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG, NULL,
 943      &subjectAltName, &size))
 944     {
 945         DWORD i;
 946
 947         for (i = 0; i < subjectAltName->cAltEntry; i++)
 948         {
 949              BOOL nameFormPresent;
 950
 951              /* A name constraint only applies if the name form is present.
 952               * From RFC 5280, section 4.2.1.10:
 953               * "Restrictions apply only when the specified name form is
 954               *  present.  If no name of the type is in the certificate,
 955               *  the certificate is acceptable."
 956               */
 957             if (alt_name_matches_excluded_name(
 958              &subjectAltName->rgAltEntry[i], nameConstraints,
 959              trustErrorStatus))
 960             {
 961                 TRACE_(chain)("subject alternate name form %d excluded\n",
 962                  subjectAltName->rgAltEntry[i].dwAltNameChoice);
 963                 *trustErrorStatus |=
 964                  CERT_TRUST_HAS_EXCLUDED_NAME_CONSTRAINT;
 965             }
 966             nameFormPresent = FALSE;
 967             if (!alt_name_matches_permitted_name(
 968              &subjectAltName->rgAltEntry[i], nameConstraints,
 969              trustErrorStatus, &nameFormPresent) && nameFormPresent)
 970             {
 971                 TRACE_(chain)("subject alternate name form %d not permitted\n",
 972                  subjectAltName->rgAltEntry[i].dwAltNameChoice);
 973                 *trustErrorStatus |=
 974                  CERT_TRUST_HAS_NOT_PERMITTED_NAME_CONSTRAINT;
 975             }
 976         }
 977         LocalFree(subjectAltName);
 978     }
 979     else
 980         *trustErrorStatus |=
 981          CERT_TRUST_INVALID_EXTENSION | CERT_TRUST_INVALID_NAME_CONSTRAINTS;
 982 }
 983
 984 static BOOL rfc822_attr_matches_excluded_name(const CERT_RDN_ATTR *attr,
 985  const CERT_NAME_CONSTRAINTS_INFO *nameConstraints, DWORD *trustErrorStatus)
 986 {
 987     DWORD i;
 988     BOOL match = FALSE;
 989
 990     for (i = 0; !match && i < nameConstraints->cExcludedSubtree; i++)
 991     {
 992         const CERT_ALT_NAME_ENTRY *constraint =
 993          &nameConstraints->rgExcludedSubtree[i].Base;
 994
 995         if (constraint->dwAltNameChoice == CERT_ALT_NAME_RFC822_NAME)
 996             match = rfc822_name_matches(constraint->u.pwszRfc822Name,
 997              (LPCWSTR)attr->Value.pbData, trustErrorStatus);
 998     }
 999     return match;
1000 }
1001
1002 static BOOL rfc822_attr_matches_permitted_name(const CERT_RDN_ATTR *attr,
1003  const CERT_NAME_CONSTRAINTS_INFO *nameConstraints, DWORD *trustErrorStatus,
1004  BOOL *present)
1005 {
1006     DWORD i;
1007     BOOL match = FALSE;
1008
1009     for (i = 0; !match && i < nameConstraints->cPermittedSubtree; i++)
1010     {
1011         const CERT_ALT_NAME_ENTRY *constraint =
1012          &nameConstraints->rgPermittedSubtree[i].Base;
1013
1014         if (constraint->dwAltNameChoice == CERT_ALT_NAME_RFC822_NAME)
1015         {
1016             *present = TRUE;
1017             match = rfc822_name_matches(constraint->u.pwszRfc822Name,
1018              (LPCWSTR)attr->Value.pbData, trustErrorStatus);
1019         }
1020     }
1021     return match;
1022 }
1023
1024 static void compare_subject_with_email_constraints(
1025  const CERT_NAME_BLOB *subjectName,
1026  const CERT_NAME_CONSTRAINTS_INFO *nameConstraints, DWORD *trustErrorStatus)
1027 {
1028     CERT_NAME_INFO *name;
1029     DWORD size;
1030
1031     if (CryptDecodeObjectEx(X509_ASN_ENCODING, X509_UNICODE_NAME,
1032      subjectName->pbData, subjectName->cbData,
1033      CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG, NULL, &name, &size))
1034     {
1035         DWORD i, j;
1036
1037         for (i = 0; i < name->cRDN; i++)
1038             for (j = 0; j < name->rgRDN[i].cRDNAttr; j++)
1039                 if (!strcmp(name->rgRDN[i].rgRDNAttr[j].pszObjId,
1040                  szOID_RSA_emailAddr))
1041                 {
1042                     BOOL nameFormPresent;
1043
1044                     /* A name constraint only applies if the name form is
1045                      * present.  From RFC 5280, section 4.2.1.10:
1046                      * "Restrictions apply only when the specified name form is
1047                      *  present.  If no name of the type is in the certificate,
1048                      *  the certificate is acceptable."
1049                      */
1050                     if (rfc822_attr_matches_excluded_name(
1051                      &name->rgRDN[i].rgRDNAttr[j], nameConstraints,
1052                      trustErrorStatus))
1053                     {
1054                         TRACE_(chain)(
1055                          "email address in subject name is excluded\n");
1056                         *trustErrorStatus |=
1057                          CERT_TRUST_HAS_EXCLUDED_NAME_CONSTRAINT;
1058                     }
1059                     nameFormPresent = FALSE;
1060                     if (!rfc822_attr_matches_permitted_name(
1061                      &name->rgRDN[i].rgRDNAttr[j], nameConstraints,
1062                      trustErrorStatus, &nameFormPresent) && nameFormPresent)
1063                     {
1064                         TRACE_(chain)(
1065                          "email address in subject name is not permitted\n");
1066                         *trustErrorStatus |=
1067                          CERT_TRUST_HAS_NOT_PERMITTED_NAME_CONSTRAINT;
1068                     }
1069                 }
1070         LocalFree(name);
1071     }
1072     else
1073         *trustErrorStatus |=
1074          CERT_TRUST_INVALID_EXTENSION | CERT_TRUST_INVALID_NAME_CONSTRAINTS;
1075 }
1076
1077 static BOOL CRYPT_IsEmptyName(const CERT_NAME_BLOB *name)
1078 {
1079     BOOL empty;
1080
1081     if (!name->cbData)
1082         empty = TRUE;
1083     else if (name->cbData == 2 && name->pbData[1] == 0)
1084     {
1085         /* An empty sequence is also empty */
1086         empty = TRUE;
1087     }
1088     else
1089         empty = FALSE;
1090     return empty;
1091 }
1092
1093 static void compare_subject_with_constraints(const CERT_NAME_BLOB *subjectName,
1094  const CERT_NAME_CONSTRAINTS_INFO *nameConstraints, DWORD *trustErrorStatus)
1095 {
1096     BOOL hasEmailConstraint = FALSE;
1097     DWORD i;
1098
1099     /* In general, a subject distinguished name only matches a directory name
1100      * constraint.  However, an exception exists for email addresses.
1101      * From RFC 5280, section 4.2.1.6:
1102      * "Legacy implementations exist where an electronic mail address is
1103      *  embedded in the subject distinguished name as an emailAddress
1104      *  attribute [RFC2985]."
1105      * If an email address constraint exists, check that constraint separately.
1106      */
1107     for (i = 0; !hasEmailConstraint && i < nameConstraints->cExcludedSubtree;
1108      i++)
1109         if (nameConstraints->rgExcludedSubtree[i].Base.dwAltNameChoice ==
1110          CERT_ALT_NAME_RFC822_NAME)
1111             hasEmailConstraint = TRUE;
1112     for (i = 0; !hasEmailConstraint && i < nameConstraints->cPermittedSubtree;
1113      i++)
1114         if (nameConstraints->rgPermittedSubtree[i].Base.dwAltNameChoice ==
1115          CERT_ALT_NAME_RFC822_NAME)
1116             hasEmailConstraint = TRUE;
1117     if (hasEmailConstraint)
1118         compare_subject_with_email_constraints(subjectName, nameConstraints,
1119          trustErrorStatus);
1120     for (i = 0; i < nameConstraints->cExcludedSubtree; i++)
1121     {
1122         CERT_ALT_NAME_ENTRY *constraint =
1123          &nameConstraints->rgExcludedSubtree[i].Base;
1124
1125         if (constraint->dwAltNameChoice == CERT_ALT_NAME_DIRECTORY_NAME &&
1126          directory_name_matches(&constraint->u.DirectoryName, subjectName))
1127         {
1128             TRACE_(chain)("subject name is excluded\n");
1129             *trustErrorStatus |=
1130              CERT_TRUST_HAS_EXCLUDED_NAME_CONSTRAINT;
1131         }
1132     }
1133     /* RFC 5280, section 4.2.1.10:
1134      * "Restrictions apply only when the specified name form is present.
1135      *  If no name of the type is in the certificate, the certificate is
1136      *  acceptable."
1137      * An empty name can't have the name form present, so don't check it.
1138      */
1139     if (nameConstraints->cPermittedSubtree && !CRYPT_IsEmptyName(subjectName))
1140     {
1141         BOOL match = FALSE, hasDirectoryConstraint = FALSE;
1142
1143         for (i = 0; !match && i < nameConstraints->cPermittedSubtree; i++)
1144         {
1145             CERT_ALT_NAME_ENTRY *constraint =
1146              &nameConstraints->rgPermittedSubtree[i].Base;
1147
1148             if (constraint->dwAltNameChoice == CERT_ALT_NAME_DIRECTORY_NAME)
1149             {
1150                 hasDirectoryConstraint = TRUE;
1151                 match = directory_name_matches(&constraint->u.DirectoryName,
1152                  subjectName);
1153             }
1154         }
1155         if (hasDirectoryConstraint && !match)
1156         {
1157             TRACE_(chain)("subject name is not permitted\n");
1158             *trustErrorStatus |= CERT_TRUST_HAS_NOT_PERMITTED_NAME_CONSTRAINT;
1159         }
1160     }
1161 }
1162
1163 static void CRYPT_CheckNameConstraints(
1164  const CERT_NAME_CONSTRAINTS_INFO *nameConstraints, const CERT_INFO *cert,
1165  DWORD *trustErrorStatus)
1166 {
1167     CERT_EXTENSION *ext = get_subject_alt_name_ext(cert);
1168
1169     if (ext)
1170         compare_alt_name_with_constraints(ext, nameConstraints,
1171          trustErrorStatus);
1172     /* Name constraints apply to the subject alternative name as well as the
1173      * subject name.  From RFC 5280, section 4.2.1.10:
1174      * "Restrictions apply to the subject distinguished name and apply to
1175      *  subject alternative names."
1176      */
1177     compare_subject_with_constraints(&cert->Subject, nameConstraints,
1178      trustErrorStatus);
1179 }
1180
1181 /* Gets cert's name constraints, if any.  Free with LocalFree. */
1182 static CERT_NAME_CONSTRAINTS_INFO *CRYPT_GetNameConstraints(CERT_INFO *cert)
1183 {
1184     CERT_NAME_CONSTRAINTS_INFO *info = NULL;
1185
1186     CERT_EXTENSION *ext;
1187
1188     if ((ext = CertFindExtension(szOID_NAME_CONSTRAINTS, cert->cExtension,
1189      cert->rgExtension)))
1190     {
1191         DWORD size;
1192
1193         CryptDecodeObjectEx(X509_ASN_ENCODING, X509_NAME_CONSTRAINTS,
1194          ext->Value.pbData, ext->Value.cbData,
1195          CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG, NULL, &info,
1196          &size);
1197     }
1198     return info;
1199 }
1200
1201 static BOOL CRYPT_IsValidNameConstraint(const CERT_NAME_CONSTRAINTS_INFO *info)
1202 {
1203     DWORD i;
1204     BOOL ret = TRUE;
1205
1206     /* Make sure at least one permitted or excluded subtree is present.  From
1207      * RFC 5280, section 4.2.1.10:
1208      * "Conforming CAs MUST NOT issue certificates where name constraints is an
1209      *  empty sequence.  That is, either the permittedSubtrees field or the
1210      *  excludedSubtrees MUST be present."
1211      */
1212     if (!info->cPermittedSubtree && !info->cExcludedSubtree)
1213     {
1214         WARN_(chain)("constraints contain no permitted nor excluded subtree\n");
1215         ret = FALSE;
1216     }
1217     /* Check that none of the constraints specifies a minimum or a maximum.
1218      * See RFC 5280, section 4.2.1.10:
1219      * "Within this profile, the minimum and maximum fields are not used with
1220      *  any name forms, thus, the minimum MUST be zero, and maximum MUST be
1221      *  absent.  However, if an application encounters a critical name
1222      *  constraints extension that specifies other values for minimum or
1223      *  maximum for a name form that appears in a subsequent certificate, the
1224      *  application MUST either process these fields or reject the
1225      *  certificate."
1226      * Since it gives no guidance as to how to process these fields, we
1227      * reject any name constraint that contains them.
1228      */
1229     for (i = 0; ret && i < info->cPermittedSubtree; i++)
1230         if (info->rgPermittedSubtree[i].dwMinimum ||
1231          info->rgPermittedSubtree[i].fMaximum)
1232         {
1233             TRACE_(chain)("found a minimum or maximum in permitted subtrees\n");
1234             ret = FALSE;
1235         }
1236     for (i = 0; ret && i < info->cExcludedSubtree; i++)
1237         if (info->rgExcludedSubtree[i].dwMinimum ||
1238          info->rgExcludedSubtree[i].fMaximum)
1239         {
1240             TRACE_(chain)("found a minimum or maximum in excluded subtrees\n");
1241             ret = FALSE;
1242         }
1243     return ret;
1244 }
1245
1246 static void CRYPT_CheckChainNameConstraints(PCERT_SIMPLE_CHAIN chain)
1247 {
1248     int i, j;
1249
1250     /* Microsoft's implementation appears to violate RFC 3280:  according to
1251      * MSDN, the various CERT_TRUST_*_NAME_CONSTRAINT errors are set if a CA's
1252      * name constraint is violated in the end cert.  According to RFC 3280,
1253      * the constraints should be checked against every subsequent certificate
1254      * in the chain, not just the end cert.
1255      * Microsoft's implementation also sets the name constraint errors on the
1256      * certs whose constraints were violated, not on the certs that violated
1257      * them.
1258      * In order to be error-compatible with Microsoft's implementation, while
1259      * still adhering to RFC 3280, I use a O(n ^ 2) algorithm to check name
1260      * constraints.
1261      */
1262     for (i = chain->cElement - 1; i > 0; i--)
1263     {
1264         CERT_NAME_CONSTRAINTS_INFO *nameConstraints;
1265
1266         if ((nameConstraints = CRYPT_GetNameConstraints(
1267          chain->rgpElement[i]->pCertContext->pCertInfo)))
1268         {
1269             if (!CRYPT_IsValidNameConstraint(nameConstraints))
1270                 chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
1271                  CERT_TRUST_HAS_NOT_SUPPORTED_NAME_CONSTRAINT;
1272             else
1273             {
1274                 for (j = i - 1; j >= 0; j--)
1275                 {
1276                     DWORD errorStatus = 0;
1277
1278                     /* According to RFC 3280, self-signed certs don't have name
1279                      * constraints checked unless they're the end cert.
1280                      */
1281                     if (j == 0 || !CRYPT_IsCertificateSelfSigned(
1282                      chain->rgpElement[j]->pCertContext))
1283                     {
1284                         CRYPT_CheckNameConstraints(nameConstraints,
1285                          chain->rgpElement[j]->pCertContext->pCertInfo,
1286                          &errorStatus);
1287                         if (errorStatus)
1288                         {
1289                             chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
1290                              errorStatus;
1291                             CRYPT_CombineTrustStatus(&chain->TrustStatus,
1292                              &chain->rgpElement[i]->TrustStatus);
1293                         }
1294                         else
1295                             chain->rgpElement[i]->TrustStatus.dwInfoStatus |=
1296                              CERT_TRUST_HAS_VALID_NAME_CONSTRAINTS;
1297                     }
1298                 }
1299             }
1300             LocalFree(nameConstraints);
1301         }
1302     }
1303 }
1304
1305 static LPWSTR name_value_to_str(const CERT_NAME_BLOB *name)
1306 {
1307     DWORD len = cert_name_to_str_with_indent(X509_ASN_ENCODING, 0, name,
1308      CERT_SIMPLE_NAME_STR, NULL, 0);
1309     LPWSTR str = NULL;
1310
1311     if (len)
1312     {
1313         str = CryptMemAlloc(len * sizeof(WCHAR));
1314         if (str)
1315             cert_name_to_str_with_indent(X509_ASN_ENCODING, 0, name,
1316              CERT_SIMPLE_NAME_STR, str, len);
1317     }
1318     return str;
1319 }
1320
1321 static void dump_alt_name_entry(const CERT_ALT_NAME_ENTRY *entry)
1322 {
1323     LPWSTR str;
1324
1325     switch (entry->dwAltNameChoice)
1326     {
1327     case CERT_ALT_NAME_OTHER_NAME:
1328         TRACE_(chain)("CERT_ALT_NAME_OTHER_NAME, oid = %s\n",
1329          debugstr_a(entry->u.pOtherName->pszObjId));
1330          break;
1331     case CERT_ALT_NAME_RFC822_NAME:
1332         TRACE_(chain)("CERT_ALT_NAME_RFC822_NAME: %s\n",
1333          debugstr_w(entry->u.pwszRfc822Name));
1334         break;
1335     case CERT_ALT_NAME_DNS_NAME:
1336         TRACE_(chain)("CERT_ALT_NAME_DNS_NAME: %s\n",
1337          debugstr_w(entry->u.pwszDNSName));
1338         break;
1339     case CERT_ALT_NAME_DIRECTORY_NAME:
1340         str = name_value_to_str(&entry->u.DirectoryName);
1341         TRACE_(chain)("CERT_ALT_NAME_DIRECTORY_NAME: %s\n", debugstr_w(str));
1342         CryptMemFree(str);
1343         break;
1344     case CERT_ALT_NAME_URL:
1345         TRACE_(chain)("CERT_ALT_NAME_URL: %s\n", debugstr_w(entry->u.pwszURL));
1346         break;
1347     case CERT_ALT_NAME_IP_ADDRESS:
1348         TRACE_(chain)("CERT_ALT_NAME_IP_ADDRESS: %d bytes\n",
1349          entry->u.IPAddress.cbData);
1350         break;
1351     case CERT_ALT_NAME_REGISTERED_ID:
1352         TRACE_(chain)("CERT_ALT_NAME_REGISTERED_ID: %s\n",
1353          debugstr_a(entry->u.pszRegisteredID));
1354         break;
1355     default:
1356         TRACE_(chain)("dwAltNameChoice = %d\n", entry->dwAltNameChoice);
1357     }
1358 }
1359
1360 static void dump_alt_name(LPCSTR type, const CERT_EXTENSION *ext)
1361 {
1362     CERT_ALT_NAME_INFO *name;
1363     DWORD size;
1364
1365     TRACE_(chain)("%s:\n", type);
1366     if (CryptDecodeObjectEx(X509_ASN_ENCODING, X509_ALTERNATE_NAME,
1367      ext->Value.pbData, ext->Value.cbData,
1368      CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG, NULL, &name, &size))
1369     {
1370         DWORD i;
1371
1372         TRACE_(chain)("%d alt name entries:\n", name->cAltEntry);
1373         for (i = 0; i < name->cAltEntry; i++)
1374             dump_alt_name_entry(&name->rgAltEntry[i]);
1375         LocalFree(name);
1376     }
1377 }
1378
1379 static void dump_basic_constraints(const CERT_EXTENSION *ext)
1380 {
1381     CERT_BASIC_CONSTRAINTS_INFO *info;
1382     DWORD size = 0;
1383
1384     if (CryptDecodeObjectEx(X509_ASN_ENCODING, szOID_BASIC_CONSTRAINTS,
1385      ext->Value.pbData, ext->Value.cbData, CRYPT_DECODE_ALLOC_FLAG,
1386      NULL, &info, &size))
1387     {
1388         TRACE_(chain)("SubjectType: %02x\n", info->SubjectType.pbData[0]);
1389         TRACE_(chain)("%s path length constraint\n",
1390          info->fPathLenConstraint ? "has" : "doesn't have");
1391         TRACE_(chain)("path length=%d\n", info->dwPathLenConstraint);
1392         LocalFree(info);
1393     }
1394 }
1395
1396 static void dump_basic_constraints2(const CERT_EXTENSION *ext)
1397 {
1398     CERT_BASIC_CONSTRAINTS2_INFO constraints;
1399     DWORD size = sizeof(CERT_BASIC_CONSTRAINTS2_INFO);
1400
1401     if (CryptDecodeObjectEx(X509_ASN_ENCODING,
1402      szOID_BASIC_CONSTRAINTS2, ext->Value.pbData, ext->Value.cbData,
1403      0, NULL, &constraints, &size))
1404     {
1405         TRACE_(chain)("basic constraints:\n");
1406         TRACE_(chain)("can%s be a CA\n", constraints.fCA ? "" : "not");
1407         TRACE_(chain)("%s path length constraint\n",
1408          constraints.fPathLenConstraint ? "has" : "doesn't have");
1409         TRACE_(chain)("path length=%d\n", constraints.dwPathLenConstraint);
1410     }
1411 }
1412
1413 static void dump_key_usage(const CERT_EXTENSION *ext)
1414 {
1415     CRYPT_BIT_BLOB usage;
1416     DWORD size = sizeof(usage);
1417
1418     if (CryptDecodeObjectEx(X509_ASN_ENCODING, X509_BITS, ext->Value.pbData,
1419      ext->Value.cbData, CRYPT_DECODE_NOCOPY_FLAG, NULL, &usage, &size))
1420     {
1421 #define trace_usage_bit(bits, bit) \
1422  if ((bits) & (bit)) TRACE_(chain)("%s\n", #bit)
1423         if (usage.cbData)
1424         {
1425             trace_usage_bit(usage.pbData[0], CERT_DIGITAL_SIGNATURE_KEY_USAGE);
1426             trace_usage_bit(usage.pbData[0], CERT_NON_REPUDIATION_KEY_USAGE);
1427             trace_usage_bit(usage.pbData[0], CERT_KEY_ENCIPHERMENT_KEY_USAGE);
1428             trace_usage_bit(usage.pbData[0], CERT_DATA_ENCIPHERMENT_KEY_USAGE);
1429             trace_usage_bit(usage.pbData[0], CERT_KEY_AGREEMENT_KEY_USAGE);
1430             trace_usage_bit(usage.pbData[0], CERT_KEY_CERT_SIGN_KEY_USAGE);
1431             trace_usage_bit(usage.pbData[0], CERT_CRL_SIGN_KEY_USAGE);
1432             trace_usage_bit(usage.pbData[0], CERT_ENCIPHER_ONLY_KEY_USAGE);
1433         }
1434 #undef trace_usage_bit
1435         if (usage.cbData > 1 && usage.pbData[1] & CERT_DECIPHER_ONLY_KEY_USAGE)
1436             TRACE_(chain)("CERT_DECIPHER_ONLY_KEY_USAGE\n");
1437     }
1438 }
1439
1440 static void dump_general_subtree(const CERT_GENERAL_SUBTREE *subtree)
1441 {
1442     dump_alt_name_entry(&subtree->Base);
1443     TRACE_(chain)("dwMinimum = %d, fMaximum = %d, dwMaximum = %d\n",
1444      subtree->dwMinimum, subtree->fMaximum, subtree->dwMaximum);
1445 }
1446
1447 static void dump_name_constraints(const CERT_EXTENSION *ext)
1448 {
1449     CERT_NAME_CONSTRAINTS_INFO *nameConstraints;
1450     DWORD size;
1451
1452     if (CryptDecodeObjectEx(X509_ASN_ENCODING, X509_NAME_CONSTRAINTS,
1453      ext->Value.pbData, ext->Value.cbData,
1454      CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG, NULL, &nameConstraints,
1455      &size))
1456     {
1457         DWORD i;
1458
1459         TRACE_(chain)("%d permitted subtrees:\n",
1460          nameConstraints->cPermittedSubtree);
1461         for (i = 0; i < nameConstraints->cPermittedSubtree; i++)
1462             dump_general_subtree(&nameConstraints->rgPermittedSubtree[i]);
1463         TRACE_(chain)("%d excluded subtrees:\n",
1464          nameConstraints->cExcludedSubtree);
1465         for (i = 0; i < nameConstraints->cExcludedSubtree; i++)
1466             dump_general_subtree(&nameConstraints->rgExcludedSubtree[i]);
1467         LocalFree(nameConstraints);
1468     }
1469 }
1470
1471 static void dump_cert_policies(const CERT_EXTENSION *ext)
1472 {
1473     CERT_POLICIES_INFO *policies;
1474     DWORD size;
1475
1476     if (CryptDecodeObjectEx(X509_ASN_ENCODING, X509_CERT_POLICIES,
1477      ext->Value.pbData, ext->Value.cbData, CRYPT_DECODE_ALLOC_FLAG, NULL,
1478      &policies, &size))
1479     {
1480         DWORD i, j;
1481
1482         TRACE_(chain)("%d policies:\n", policies->cPolicyInfo);
1483         for (i = 0; i < policies->cPolicyInfo; i++)
1484         {
1485             TRACE_(chain)("policy identifier: %s\n",
1486              debugstr_a(policies->rgPolicyInfo[i].pszPolicyIdentifier));
1487             TRACE_(chain)("%d policy qualifiers:\n",
1488              policies->rgPolicyInfo[i].cPolicyQualifier);
1489             for (j = 0; j < policies->rgPolicyInfo[i].cPolicyQualifier; j++)
1490                 TRACE_(chain)("%s\n", debugstr_a(
1491                  policies->rgPolicyInfo[i].rgPolicyQualifier[j].
1492                  pszPolicyQualifierId));
1493         }
1494         LocalFree(policies);
1495     }
1496 }
1497
1498 static void dump_enhanced_key_usage(const CERT_EXTENSION *ext)
1499 {
1500     CERT_ENHKEY_USAGE *usage;
1501     DWORD size;
1502
1503     if (CryptDecodeObjectEx(X509_ASN_ENCODING, X509_ENHANCED_KEY_USAGE,
1504      ext->Value.pbData, ext->Value.cbData, CRYPT_DECODE_ALLOC_FLAG, NULL,
1505      &usage, &size))
1506     {
1507         DWORD i;
1508
1509         TRACE_(chain)("%d usages:\n", usage->cUsageIdentifier);
1510         for (i = 0; i < usage->cUsageIdentifier; i++)
1511             TRACE_(chain)("%s\n", usage->rgpszUsageIdentifier[i]);
1512         LocalFree(usage);
1513     }
1514 }
1515
1516 static void dump_netscape_cert_type(const CERT_EXTENSION *ext)
1517 {
1518     CRYPT_BIT_BLOB usage;
1519     DWORD size = sizeof(usage);
1520
1521     if (CryptDecodeObjectEx(X509_ASN_ENCODING, X509_BITS, ext->Value.pbData,
1522      ext->Value.cbData, CRYPT_DECODE_NOCOPY_FLAG, NULL, &usage, &size))
1523     {
1524 #define trace_cert_type_bit(bits, bit) \
1525  if ((bits) & (bit)) TRACE_(chain)("%s\n", #bit)
1526         if (usage.cbData)
1527         {
1528             trace_cert_type_bit(usage.pbData[0],
1529              NETSCAPE_SSL_CLIENT_AUTH_CERT_TYPE);
1530             trace_cert_type_bit(usage.pbData[0],
1531              NETSCAPE_SSL_SERVER_AUTH_CERT_TYPE);
1532             trace_cert_type_bit(usage.pbData[0], NETSCAPE_SMIME_CERT_TYPE);
1533             trace_cert_type_bit(usage.pbData[0], NETSCAPE_SIGN_CERT_TYPE);
1534             trace_cert_type_bit(usage.pbData[0], NETSCAPE_SSL_CA_CERT_TYPE);
1535             trace_cert_type_bit(usage.pbData[0], NETSCAPE_SMIME_CA_CERT_TYPE);
1536             trace_cert_type_bit(usage.pbData[0], NETSCAPE_SIGN_CA_CERT_TYPE);
1537         }
1538 #undef trace_cert_type_bit
1539     }
1540 }
1541
1542 static void dump_extension(const CERT_EXTENSION *ext)
1543 {
1544     TRACE_(chain)("%s (%scritical)\n", debugstr_a(ext->pszObjId),
1545      ext->fCritical ? "" : "not ");
1546     if (!strcmp(ext->pszObjId, szOID_SUBJECT_ALT_NAME))
1547         dump_alt_name("subject alt name", ext);
1548     else  if (!strcmp(ext->pszObjId, szOID_ISSUER_ALT_NAME))
1549         dump_alt_name("issuer alt name", ext);
1550     else if (!strcmp(ext->pszObjId, szOID_BASIC_CONSTRAINTS))
1551         dump_basic_constraints(ext);
1552     else if (!strcmp(ext->pszObjId, szOID_KEY_USAGE))
1553         dump_key_usage(ext);
1554     else if (!strcmp(ext->pszObjId, szOID_SUBJECT_ALT_NAME2))
1555         dump_alt_name("subject alt name 2", ext);
1556     else if (!strcmp(ext->pszObjId, szOID_ISSUER_ALT_NAME2))
1557         dump_alt_name("issuer alt name 2", ext);
1558     else if (!strcmp(ext->pszObjId, szOID_BASIC_CONSTRAINTS2))
1559         dump_basic_constraints2(ext);
1560     else if (!strcmp(ext->pszObjId, szOID_NAME_CONSTRAINTS))
1561         dump_name_constraints(ext);
1562     else if (!strcmp(ext->pszObjId, szOID_CERT_POLICIES))
1563         dump_cert_policies(ext);
1564     else if (!strcmp(ext->pszObjId, szOID_ENHANCED_KEY_USAGE))
1565         dump_enhanced_key_usage(ext);
1566     else if (!strcmp(ext->pszObjId, szOID_NETSCAPE_CERT_TYPE))
1567         dump_netscape_cert_type(ext);
1568 }
1569
1570 static LPCWSTR filetime_to_str(const FILETIME *time)
1571 {
1572     static WCHAR date[80];
1573     WCHAR dateFmt[80]; /* sufficient for all versions of LOCALE_SSHORTDATE */
1574     SYSTEMTIME sysTime;
1575
1576     if (!time) return NULL;
1577
1578     GetLocaleInfoW(LOCALE_SYSTEM_DEFAULT, LOCALE_SSHORTDATE, dateFmt,
1579      sizeof(dateFmt) / sizeof(dateFmt[0]));
1580     FileTimeToSystemTime(time, &sysTime);
1581     GetDateFormatW(LOCALE_SYSTEM_DEFAULT, 0, &sysTime, dateFmt, date,
1582      sizeof(date) / sizeof(date[0]));
1583     return date;
1584 }
1585
1586 static void dump_element(PCCERT_CONTEXT cert)
1587 {
1588     LPWSTR name = NULL;
1589     DWORD len, i;
1590
1591     TRACE_(chain)("%p: version %d\n", cert, cert->pCertInfo->dwVersion);
1592     len = CertGetNameStringW(cert, CERT_NAME_SIMPLE_DISPLAY_TYPE,
1593      CERT_NAME_ISSUER_FLAG, NULL, NULL, 0);
1594     name = CryptMemAlloc(len * sizeof(WCHAR));
1595     if (name)
1596     {
1597         CertGetNameStringW(cert, CERT_NAME_SIMPLE_DISPLAY_TYPE,
1598          CERT_NAME_ISSUER_FLAG, NULL, name, len);
1599         TRACE_(chain)("issued by %s\n", debugstr_w(name));
1600         CryptMemFree(name);
1601     }
1602     len = CertGetNameStringW(cert, CERT_NAME_SIMPLE_DISPLAY_TYPE, 0, NULL,
1603      NULL, 0);
1604     name = CryptMemAlloc(len * sizeof(WCHAR));
1605     if (name)
1606     {
1607         CertGetNameStringW(cert, CERT_NAME_SIMPLE_DISPLAY_TYPE, 0, NULL,
1608          name, len);
1609         TRACE_(chain)("issued to %s\n", debugstr_w(name));
1610         CryptMemFree(name);
1611     }
1612     TRACE_(chain)("valid from %s to %s\n",
1613      debugstr_w(filetime_to_str(&cert->pCertInfo->NotBefore)),
1614      debugstr_w(filetime_to_str(&cert->pCertInfo->NotAfter)));
1615     TRACE_(chain)("%d extensions\n", cert->pCertInfo->cExtension);
1616     for (i = 0; i < cert->pCertInfo->cExtension; i++)
1617         dump_extension(&cert->pCertInfo->rgExtension[i]);
1618 }
1619
1620 static BOOL CRYPT_KeyUsageValid(PCertificateChainEngine engine,
1621  PCCERT_CONTEXT cert, BOOL isRoot, BOOL isCA, DWORD index)
1622 {
1623     PCERT_EXTENSION ext;
1624     BOOL ret;
1625     BYTE usageBits = 0;
1626
1627     ext = CertFindExtension(szOID_KEY_USAGE, cert->pCertInfo->cExtension,
1628      cert->pCertInfo->rgExtension);
1629     if (ext)
1630     {
1631         CRYPT_BIT_BLOB usage;
1632         DWORD size = sizeof(usage);
1633
1634         ret = CryptDecodeObjectEx(cert->dwCertEncodingType, X509_BITS,
1635          ext->Value.pbData, ext->Value.cbData, CRYPT_DECODE_NOCOPY_FLAG, NULL,
1636          &usage, &size);
1637         if (!ret)
1638             return FALSE;
1639         else if (usage.cbData > 2)
1640         {
1641             /* The key usage extension only defines 9 bits => no more than 2
1642              * bytes are needed to encode all known usages.
1643              */
1644             return FALSE;
1645         }
1646         else
1647         {
1648             /* The only bit relevant to chain validation is the keyCertSign
1649              * bit, which is always in the least significant byte of the
1650              * key usage bits.
1651              */
1652             usageBits = usage.pbData[usage.cbData - 1];
1653         }
1654     }
1655     if (isCA)
1656     {
1657         if (!ext)
1658         {
1659             /* MS appears to violate RFC 5280, section 4.2.1.3 (Key Usage)
1660              * here.  Quoting the RFC:
1661              * "This [key usage] extension MUST appear in certificates that
1662              * contain public keys that are used to validate digital signatures
1663              * on other public key certificates or CRLs."
1664              * MS appears to accept certs that do not contain key usage
1665              * extensions as CA certs.  V1 and V2 certificates did not have
1666              * extensions, and many root certificates are V1 certificates, so
1667              * perhaps this is prudent.  On the other hand, MS also accepts V3
1668              * certs without key usage extensions.  We are more restrictive:
1669              * we accept locally installed V1 or V2 certs as CA certs.
1670              * We also accept a lack of key usage extension on root certs,
1671              * which is implied in RFC 5280, section 6.1:  the trust anchor's
1672              * only requirement is that it was used to issue the next
1673              * certificate in the chain.
1674              */
1675             if (isRoot)
1676                 ret = TRUE;
1677             else if (cert->pCertInfo->dwVersion == CERT_V1 ||
1678              cert->pCertInfo->dwVersion == CERT_V2)
1679             {
1680                 PCCERT_CONTEXT localCert = CRYPT_FindCertInStore(
1681                  engine->hWorld, cert);
1682
1683                 ret = localCert != NULL;
1684                 CertFreeCertificateContext(localCert);
1685             }
1686             else
1687                 ret = FALSE;
1688             if (!ret)
1689                 WARN_(chain)("no key usage extension on a CA cert\n");
1690         }
1691         else
1692         {
1693             if (!(usageBits & CERT_KEY_CERT_SIGN_KEY_USAGE))
1694             {
1695                 WARN_(chain)("keyCertSign not asserted on a CA cert\n");
1696                 ret = FALSE;
1697             }
1698             else
1699                 ret = TRUE;
1700         }
1701     }
1702     else
1703     {
1704         if (ext && (usageBits & CERT_KEY_CERT_SIGN_KEY_USAGE))
1705         {
1706             WARN_(chain)("keyCertSign asserted on a non-CA cert\n");
1707             ret = FALSE;
1708         }
1709         else
1710             ret = TRUE;
1711     }
1712     return ret;
1713 }
1714
1715 static BOOL CRYPT_CriticalExtensionsSupported(PCCERT_CONTEXT cert)
1716 {
1717     BOOL ret = TRUE;
1718     DWORD i;
1719
1720     for (i = 0; ret && i < cert->pCertInfo->cExtension; i++)
1721     {
1722         if (cert->pCertInfo->rgExtension[i].fCritical)
1723         {
1724             LPCSTR oid = cert->pCertInfo->rgExtension[i].pszObjId;
1725
1726             if (!strcmp(oid, szOID_BASIC_CONSTRAINTS))
1727                 ret = TRUE;
1728             else if (!strcmp(oid, szOID_BASIC_CONSTRAINTS2))
1729                 ret = TRUE;
1730             else if (!strcmp(oid, szOID_NAME_CONSTRAINTS))
1731                 ret = TRUE;
1732             else if (!strcmp(oid, szOID_KEY_USAGE))
1733                 ret = TRUE;
1734             else if (!strcmp(oid, szOID_SUBJECT_ALT_NAME))
1735                 ret = TRUE;
1736             else if (!strcmp(oid, szOID_SUBJECT_ALT_NAME2))
1737                 ret = TRUE;
1738             else if (!strcmp(oid, szOID_ENHANCED_KEY_USAGE))
1739                 ret = TRUE;
1740             else
1741             {
1742                 FIXME("unsupported critical extension %s\n",
1743                  debugstr_a(oid));
1744                 ret = FALSE;
1745             }
1746         }
1747     }
1748     return ret;
1749 }
1750
1751 static BOOL CRYPT_IsCertVersionValid(PCCERT_CONTEXT cert)
1752 {
1753     BOOL ret = TRUE;
1754
1755     /* Checks whether the contents of the cert match the cert's version. */
1756     switch (cert->pCertInfo->dwVersion)
1757     {
1758     case CERT_V1:
1759         /* A V1 cert may not contain unique identifiers.  See RFC 5280,
1760          * section 4.1.2.8:
1761          * "These fields MUST only appear if the version is 2 or 3 (Section
1762          *  4.1.2.1).  These fields MUST NOT appear if the version is 1."
1763          */
1764         if (cert->pCertInfo->IssuerUniqueId.cbData ||
1765          cert->pCertInfo->SubjectUniqueId.cbData)
1766             ret = FALSE;
1767         /* A V1 cert may not contain extensions.  See RFC 5280, section 4.1.2.9:
1768          * "This field MUST only appear if the version is 3 (Section 4.1.2.1)."
1769          */
1770         if (cert->pCertInfo->cExtension)
1771             ret = FALSE;
1772         break;
1773     case CERT_V2:
1774         /* A V2 cert may not contain extensions.  See RFC 5280, section 4.1.2.9:
1775          * "This field MUST only appear if the version is 3 (Section 4.1.2.1)."
1776          */
1777         if (cert->pCertInfo->cExtension)
1778             ret = FALSE;
1779         break;
1780     case CERT_V3:
1781         /* Do nothing, all fields are allowed for V3 certs */
1782         break;
1783     default:
1784         WARN_(chain)("invalid cert version %d\n", cert->pCertInfo->dwVersion);
1785         ret = FALSE;
1786     }
1787     return ret;
1788 }
1789
1790 static void CRYPT_CheckSimpleChain(PCertificateChainEngine engine,
1791  PCERT_SIMPLE_CHAIN chain, LPFILETIME time)
1792 {
1793     PCERT_CHAIN_ELEMENT rootElement = chain->rgpElement[chain->cElement - 1];
1794     int i;
1795     BOOL pathLengthConstraintViolated = FALSE;
1796     CERT_BASIC_CONSTRAINTS2_INFO constraints = { FALSE, FALSE, 0 };
1797
1798     TRACE_(chain)("checking chain with %d elements for time %s\n",
1799      chain->cElement, debugstr_w(filetime_to_str(time)));
1800     for (i = chain->cElement - 1; i >= 0; i--)
1801     {
1802         BOOL isRoot;
1803
1804         if (TRACE_ON(chain))
1805             dump_element(chain->rgpElement[i]->pCertContext);
1806         if (i == chain->cElement - 1)
1807             isRoot = CRYPT_IsCertificateSelfSigned(
1808              chain->rgpElement[i]->pCertContext);
1809         else
1810             isRoot = FALSE;
1811         if (!CRYPT_IsCertVersionValid(chain->rgpElement[i]->pCertContext))
1812         {
1813             /* MS appears to accept certs whose versions don't match their
1814              * contents, so there isn't an appropriate error code.
1815              */
1816             chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
1817              CERT_TRUST_INVALID_EXTENSION;
1818         }
1819         if (CertVerifyTimeValidity(time,
1820          chain->rgpElement[i]->pCertContext->pCertInfo) != 0)
1821             chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
1822              CERT_TRUST_IS_NOT_TIME_VALID;
1823         if (i != 0)
1824         {
1825             /* Check the signature of the cert this issued */
1826             if (!CryptVerifyCertificateSignatureEx(0, X509_ASN_ENCODING,
1827              CRYPT_VERIFY_CERT_SIGN_SUBJECT_CERT,
1828              (void *)chain->rgpElement[i - 1]->pCertContext,
1829              CRYPT_VERIFY_CERT_SIGN_ISSUER_CERT,
1830              (void *)chain->rgpElement[i]->pCertContext, 0, NULL))
1831                 chain->rgpElement[i - 1]->TrustStatus.dwErrorStatus |=
1832                  CERT_TRUST_IS_NOT_SIGNATURE_VALID;
1833             /* Once a path length constraint has been violated, every remaining
1834              * CA cert's basic constraints is considered invalid.
1835              */
1836             if (pathLengthConstraintViolated)
1837                 chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
1838                  CERT_TRUST_INVALID_BASIC_CONSTRAINTS;
1839             else if (!CRYPT_CheckBasicConstraintsForCA(engine,
1840              chain->rgpElement[i]->pCertContext, &constraints, i - 1, isRoot,
1841              &pathLengthConstraintViolated))
1842                 chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
1843                  CERT_TRUST_INVALID_BASIC_CONSTRAINTS;
1844             else if (constraints.fPathLenConstraint &&
1845              constraints.dwPathLenConstraint)
1846             {
1847                 /* This one's valid - decrement max length */
1848                 constraints.dwPathLenConstraint--;
1849             }
1850         }
1851         else
1852         {
1853             /* Check whether end cert has a basic constraints extension */
1854             if (!CRYPT_DecodeBasicConstraints(
1855              chain->rgpElement[i]->pCertContext, &constraints, FALSE))
1856                 chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
1857                  CERT_TRUST_INVALID_BASIC_CONSTRAINTS;
1858         }
1859         if (!CRYPT_KeyUsageValid(engine, chain->rgpElement[i]->pCertContext,
1860          isRoot, constraints.fCA, i))
1861             chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
1862              CERT_TRUST_IS_NOT_VALID_FOR_USAGE;
1863         if (CRYPT_IsSimpleChainCyclic(chain))
1864         {
1865             /* If the chain is cyclic, then the path length constraints
1866              * are violated, because the chain is infinitely long.
1867              */
1868             pathLengthConstraintViolated = TRUE;
1869             chain->TrustStatus.dwErrorStatus |=
1870              CERT_TRUST_IS_PARTIAL_CHAIN |
1871              CERT_TRUST_INVALID_BASIC_CONSTRAINTS;
1872         }
1873         /* Check whether every critical extension is supported */
1874         if (!CRYPT_CriticalExtensionsSupported(
1875          chain->rgpElement[i]->pCertContext))
1876             chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
1877              CERT_TRUST_INVALID_EXTENSION;
1878         CRYPT_CombineTrustStatus(&chain->TrustStatus,
1879          &chain->rgpElement[i]->TrustStatus);
1880     }
1881     CRYPT_CheckChainNameConstraints(chain);
1882     if (CRYPT_IsCertificateSelfSigned(rootElement->pCertContext))
1883     {
1884         rootElement->TrustStatus.dwInfoStatus |=
1885          CERT_TRUST_IS_SELF_SIGNED | CERT_TRUST_HAS_NAME_MATCH_ISSUER;
1886         CRYPT_CheckRootCert(engine->hRoot, rootElement);
1887     }
1888     CRYPT_CombineTrustStatus(&chain->TrustStatus, &rootElement->TrustStatus);
1889 }
1890
1891 static PCCERT_CONTEXT CRYPT_GetIssuer(HCERTSTORE store, PCCERT_CONTEXT subject,
1892  PCCERT_CONTEXT prevIssuer, DWORD *infoStatus)
1893 {
1894     PCCERT_CONTEXT issuer = NULL;
1895     PCERT_EXTENSION ext;
1896     DWORD size;
1897
1898     *infoStatus = 0;
1899     if ((ext = CertFindExtension(szOID_AUTHORITY_KEY_IDENTIFIER,
1900      subject->pCertInfo->cExtension, subject->pCertInfo->rgExtension)))
1901     {
1902         CERT_AUTHORITY_KEY_ID_INFO *info;
1903         BOOL ret;
1904
1905         ret = CryptDecodeObjectEx(subject->dwCertEncodingType,
1906          X509_AUTHORITY_KEY_ID, ext->Value.pbData, ext->Value.cbData,
1907          CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG, NULL,
1908          &info, &size);
1909         if (ret)
1910         {
1911             CERT_ID id;
1912
1913             if (info->CertIssuer.cbData && info->CertSerialNumber.cbData)
1914             {
1915                 id.dwIdChoice = CERT_ID_ISSUER_SERIAL_NUMBER;
1916                 memcpy(&id.u.IssuerSerialNumber.Issuer, &info->CertIssuer,
1917                  sizeof(CERT_NAME_BLOB));
1918                 memcpy(&id.u.IssuerSerialNumber.SerialNumber,
1919                  &info->CertSerialNumber, sizeof(CRYPT_INTEGER_BLOB));
1920                 issuer = CertFindCertificateInStore(store,
1921                  subject->dwCertEncodingType, 0, CERT_FIND_CERT_ID, &id,
1922                  prevIssuer);
1923                 if (issuer)
1924                 {
1925                     TRACE_(chain)("issuer found by issuer/serial number\n");
1926                     *infoStatus = CERT_TRUST_HAS_EXACT_MATCH_ISSUER;
1927                 }
1928             }
1929             else if (info->KeyId.cbData)
1930             {
1931                 id.dwIdChoice = CERT_ID_KEY_IDENTIFIER;
1932                 memcpy(&id.u.KeyId, &info->KeyId, sizeof(CRYPT_HASH_BLOB));
1933                 issuer = CertFindCertificateInStore(store,
1934                  subject->dwCertEncodingType, 0, CERT_FIND_CERT_ID, &id,
1935                  prevIssuer);
1936                 if (issuer)
1937                 {
1938                     TRACE_(chain)("issuer found by key id\n");
1939                     *infoStatus = CERT_TRUST_HAS_KEY_MATCH_ISSUER;
1940                 }
1941             }
1942             LocalFree(info);
1943         }
1944     }
1945     else if ((ext = CertFindExtension(szOID_AUTHORITY_KEY_IDENTIFIER2,
1946      subject->pCertInfo->cExtension, subject->pCertInfo->rgExtension)))
1947     {
1948         CERT_AUTHORITY_KEY_ID2_INFO *info;
1949         BOOL ret;
1950
1951         ret = CryptDecodeObjectEx(subject->dwCertEncodingType,
1952          X509_AUTHORITY_KEY_ID2, ext->Value.pbData, ext->Value.cbData,
1953          CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG, NULL,
1954          &info, &size);
1955         if (ret)
1956         {
1957             CERT_ID id;
1958
1959             if (info->AuthorityCertIssuer.cAltEntry &&
1960              info->AuthorityCertSerialNumber.cbData)
1961             {
1962                 PCERT_ALT_NAME_ENTRY directoryName = NULL;
1963                 DWORD i;
1964
1965                 for (i = 0; !directoryName &&
1966                  i < info->AuthorityCertIssuer.cAltEntry; i++)
1967                     if (info->AuthorityCertIssuer.rgAltEntry[i].dwAltNameChoice
1968                      == CERT_ALT_NAME_DIRECTORY_NAME)
1969                         directoryName =
1970                          &info->AuthorityCertIssuer.rgAltEntry[i];
1971                 if (directoryName)
1972                 {
1973                     id.dwIdChoice = CERT_ID_ISSUER_SERIAL_NUMBER;
1974                     memcpy(&id.u.IssuerSerialNumber.Issuer,
1975                      &directoryName->u.DirectoryName, sizeof(CERT_NAME_BLOB));
1976                     memcpy(&id.u.IssuerSerialNumber.SerialNumber,
1977                      &info->AuthorityCertSerialNumber,
1978                      sizeof(CRYPT_INTEGER_BLOB));
1979                     issuer = CertFindCertificateInStore(store,
1980                      subject->dwCertEncodingType, 0, CERT_FIND_CERT_ID, &id,
1981                      prevIssuer);
1982                     if (issuer)
1983                     {
1984                         TRACE_(chain)("issuer found by directory name\n");
1985                         *infoStatus = CERT_TRUST_HAS_EXACT_MATCH_ISSUER;
1986                     }
1987                 }
1988                 else
1989                     FIXME("no supported name type in authority key id2\n");
1990             }
1991             else if (info->KeyId.cbData)
1992             {
1993                 id.dwIdChoice = CERT_ID_KEY_IDENTIFIER;
1994                 memcpy(&id.u.KeyId, &info->KeyId, sizeof(CRYPT_HASH_BLOB));
1995                 issuer = CertFindCertificateInStore(store,
1996                  subject->dwCertEncodingType, 0, CERT_FIND_CERT_ID, &id,
1997                  prevIssuer);
1998                 if (issuer)
1999                 {
2000                     TRACE_(chain)("issuer found by key id\n");
2001                     *infoStatus = CERT_TRUST_HAS_KEY_MATCH_ISSUER;
2002                 }
2003             }
2004             LocalFree(info);
2005         }
2006     }
2007     else
2008     {
2009         issuer = CertFindCertificateInStore(store,
2010          subject->dwCertEncodingType, 0, CERT_FIND_SUBJECT_NAME,
2011          &subject->pCertInfo->Issuer, prevIssuer);
2012         TRACE_(chain)("issuer found by name\n");
2013         *infoStatus = CERT_TRUST_HAS_NAME_MATCH_ISSUER;
2014     }
2015     return issuer;
2016 }
2017
2018 /* Builds a simple chain by finding an issuer for the last cert in the chain,
2019  * until reaching a self-signed cert, or until no issuer can be found.
2020  */
2021 static BOOL CRYPT_BuildSimpleChain(const CertificateChainEngine *engine,
2022  HCERTSTORE world, PCERT_SIMPLE_CHAIN chain)
2023 {
2024     BOOL ret = TRUE;
2025     PCCERT_CONTEXT cert = chain->rgpElement[chain->cElement - 1]->pCertContext;
2026
2027     while (ret && !CRYPT_IsSimpleChainCyclic(chain) &&
2028      !CRYPT_IsCertificateSelfSigned(cert))
2029     {
2030         PCCERT_CONTEXT issuer = CRYPT_GetIssuer(world, cert, NULL,
2031          &chain->rgpElement[chain->cElement - 1]->TrustStatus.dwInfoStatus);
2032
2033         if (issuer)
2034         {
2035             ret = CRYPT_AddCertToSimpleChain(engine, chain, issuer,
2036              chain->rgpElement[chain->cElement - 1]->TrustStatus.dwInfoStatus);
2037             /* CRYPT_AddCertToSimpleChain add-ref's the issuer, so free it to
2038              * close the enumeration that found it
2039              */
2040             CertFreeCertificateContext(issuer);
2041             cert = issuer;
2042         }
2043         else
2044         {
2045             TRACE_(chain)("Couldn't find issuer, halting chain creation\n");
2046             chain->TrustStatus.dwErrorStatus |= CERT_TRUST_IS_PARTIAL_CHAIN;
2047             break;
2048         }
2049     }
2050     return ret;
2051 }
2052
2053 static BOOL CRYPT_GetSimpleChainForCert(PCertificateChainEngine engine,
2054  HCERTSTORE world, PCCERT_CONTEXT cert, LPFILETIME pTime,
2055  PCERT_SIMPLE_CHAIN *ppChain)
2056 {
2057     BOOL ret = FALSE;
2058     PCERT_SIMPLE_CHAIN chain;
2059
2060     TRACE("(%p, %p, %p, %p)\n", engine, world, cert, pTime);
2061
2062     chain = CryptMemAlloc(sizeof(CERT_SIMPLE_CHAIN));
2063     if (chain)
2064     {
2065         memset(chain, 0, sizeof(CERT_SIMPLE_CHAIN));
2066         chain->cbSize = sizeof(CERT_SIMPLE_CHAIN);
2067         ret = CRYPT_AddCertToSimpleChain(engine, chain, cert, 0);
2068         if (ret)
2069         {
2070             ret = CRYPT_BuildSimpleChain(engine, world, chain);
2071             if (ret)
2072                 CRYPT_CheckSimpleChain(engine, chain, pTime);
2073         }
2074         if (!ret)
2075         {
2076             CRYPT_FreeSimpleChain(chain);
2077             chain = NULL;
2078         }
2079         *ppChain = chain;
2080     }
2081     return ret;
2082 }
2083
2084 static BOOL CRYPT_BuildCandidateChainFromCert(HCERTCHAINENGINE hChainEngine,
2085  PCCERT_CONTEXT cert, LPFILETIME pTime, HCERTSTORE hAdditionalStore,
2086  PCertificateChain *ppChain)
2087 {
2088     PCertificateChainEngine engine = (PCertificateChainEngine)hChainEngine;
2089     PCERT_SIMPLE_CHAIN simpleChain = NULL;
2090     HCERTSTORE world;
2091     BOOL ret;
2092
2093     world = CertOpenStore(CERT_STORE_PROV_COLLECTION, 0, 0,
2094      CERT_STORE_CREATE_NEW_FLAG, NULL);
2095     CertAddStoreToCollection(world, engine->hWorld, 0, 0);
2096     if (hAdditionalStore)
2097         CertAddStoreToCollection(world, hAdditionalStore, 0, 0);
2098     /* FIXME: only simple chains are supported for now, as CTLs aren't
2099      * supported yet.
2100      */
2101     if ((ret = CRYPT_GetSimpleChainForCert(engine, world, cert, pTime,
2102      &simpleChain)))
2103     {
2104         PCertificateChain chain = CryptMemAlloc(sizeof(CertificateChain));
2105
2106         if (chain)
2107         {
2108             chain->ref = 1;
2109             chain->world = world;
2110             chain->context.cbSize = sizeof(CERT_CHAIN_CONTEXT);
2111             chain->context.TrustStatus = simpleChain->TrustStatus;
2112             chain->context.cChain = 1;
2113             chain->context.rgpChain = CryptMemAlloc(sizeof(PCERT_SIMPLE_CHAIN));
2114             chain->context.rgpChain[0] = simpleChain;
2115             chain->context.cLowerQualityChainContext = 0;
2116             chain->context.rgpLowerQualityChainContext = NULL;
2117             chain->context.fHasRevocationFreshnessTime = FALSE;
2118             chain->context.dwRevocationFreshnessTime = 0;
2119         }
2120         else
2121             ret = FALSE;
2122         *ppChain = chain;
2123     }
2124     return ret;
2125 }
2126
2127 /* Makes and returns a copy of chain, up to and including element iElement. */
2128 static PCERT_SIMPLE_CHAIN CRYPT_CopySimpleChainToElement(
2129  const CERT_SIMPLE_CHAIN *chain, DWORD iElement)
2130 {
2131     PCERT_SIMPLE_CHAIN copy = CryptMemAlloc(sizeof(CERT_SIMPLE_CHAIN));
2132
2133     if (copy)
2134     {
2135         memset(copy, 0, sizeof(CERT_SIMPLE_CHAIN));
2136         copy->cbSize = sizeof(CERT_SIMPLE_CHAIN);
2137         copy->rgpElement =
2138          CryptMemAlloc((iElement + 1) * sizeof(PCERT_CHAIN_ELEMENT));
2139         if (copy->rgpElement)
2140         {
2141             DWORD i;
2142             BOOL ret = TRUE;
2143
2144             memset(copy->rgpElement, 0,
2145              (iElement + 1) * sizeof(PCERT_CHAIN_ELEMENT));
2146             for (i = 0; ret && i <= iElement; i++)
2147             {
2148                 PCERT_CHAIN_ELEMENT element =
2149                  CryptMemAlloc(sizeof(CERT_CHAIN_ELEMENT));
2150
2151                 if (element)
2152                 {
2153                     *element = *chain->rgpElement[i];
2154                     element->pCertContext = CertDuplicateCertificateContext(
2155                      chain->rgpElement[i]->pCertContext);
2156                     /* Reset the trust status of the copied element, it'll get
2157                      * rechecked after the new chain is done.
2158                      */
2159                     memset(&element->TrustStatus, 0, sizeof(CERT_TRUST_STATUS));
2160                     copy->rgpElement[copy->cElement++] = element;
2161                 }
2162                 else
2163                     ret = FALSE;
2164             }
2165             if (!ret)
2166             {
2167                 for (i = 0; i <= iElement; i++)
2168                     CryptMemFree(copy->rgpElement[i]);
2169                 CryptMemFree(copy->rgpElement);
2170                 CryptMemFree(copy);
2171                 copy = NULL;
2172             }
2173         }
2174         else
2175         {
2176             CryptMemFree(copy);
2177             copy = NULL;
2178         }
2179     }
2180     return copy;
2181 }
2182
2183 static void CRYPT_FreeLowerQualityChains(PCertificateChain chain)
2184 {
2185     DWORD i;
2186
2187     for (i = 0; i < chain->context.cLowerQualityChainContext; i++)
2188         CertFreeCertificateChain(chain->context.rgpLowerQualityChainContext[i]);
2189     CryptMemFree(chain->context.rgpLowerQualityChainContext);
2190     chain->context.cLowerQualityChainContext = 0;
2191     chain->context.rgpLowerQualityChainContext = NULL;
2192 }
2193
2194 static void CRYPT_FreeChainContext(PCertificateChain chain)
2195 {
2196     DWORD i;
2197
2198     CRYPT_FreeLowerQualityChains(chain);
2199     for (i = 0; i < chain->context.cChain; i++)
2200         CRYPT_FreeSimpleChain(chain->context.rgpChain[i]);
2201     CryptMemFree(chain->context.rgpChain);
2202     CertCloseStore(chain->world, 0);
2203     CryptMemFree(chain);
2204 }
2205
2206 /* Makes and returns a copy of chain, up to and including element iElement of
2207  * simple chain iChain.
2208  */
2209 static PCertificateChain CRYPT_CopyChainToElement(PCertificateChain chain,
2210  DWORD iChain, DWORD iElement)
2211 {
2212     PCertificateChain copy = CryptMemAlloc(sizeof(CertificateChain));
2213
2214     if (copy)
2215     {
2216         copy->ref = 1;
2217         copy->world = CertDuplicateStore(chain->world);
2218         copy->context.cbSize = sizeof(CERT_CHAIN_CONTEXT);
2219         /* Leave the trust status of the copied chain unset, it'll get
2220          * rechecked after the new chain is done.
2221          */
2222         memset(&copy->context.TrustStatus, 0, sizeof(CERT_TRUST_STATUS));
2223         copy->context.cLowerQualityChainContext = 0;
2224         copy->context.rgpLowerQualityChainContext = NULL;
2225         copy->context.fHasRevocationFreshnessTime = FALSE;
2226         copy->context.dwRevocationFreshnessTime = 0;
2227         copy->context.rgpChain = CryptMemAlloc(
2228          (iChain + 1) * sizeof(PCERT_SIMPLE_CHAIN));
2229         if (copy->context.rgpChain)
2230         {
2231             BOOL ret = TRUE;
2232             DWORD i;
2233
2234             memset(copy->context.rgpChain, 0,
2235              (iChain + 1) * sizeof(PCERT_SIMPLE_CHAIN));
2236             if (iChain)
2237             {
2238                 for (i = 0; ret && iChain && i < iChain - 1; i++)
2239                 {
2240                     copy->context.rgpChain[i] =
2241                      CRYPT_CopySimpleChainToElement(chain->context.rgpChain[i],
2242                      chain->context.rgpChain[i]->cElement - 1);
2243                     if (!copy->context.rgpChain[i])
2244                         ret = FALSE;
2245                 }
2246             }
2247             else
2248                 i = 0;
2249             if (ret)
2250             {
2251                 copy->context.rgpChain[i] =
2252                  CRYPT_CopySimpleChainToElement(chain->context.rgpChain[i],
2253                  iElement);
2254                 if (!copy->context.rgpChain[i])
2255                     ret = FALSE;
2256             }
2257             if (!ret)
2258             {
2259                 CRYPT_FreeChainContext(copy);
2260                 copy = NULL;
2261             }
2262             else
2263                 copy->context.cChain = iChain + 1;
2264         }
2265         else
2266         {
2267             CryptMemFree(copy);
2268             copy = NULL;
2269         }
2270     }
2271     return copy;
2272 }
2273
2274 static PCertificateChain CRYPT_BuildAlternateContextFromChain(
2275  HCERTCHAINENGINE hChainEngine, LPFILETIME pTime, HCERTSTORE hAdditionalStore,
2276  PCertificateChain chain)
2277 {
2278     PCertificateChainEngine engine = (PCertificateChainEngine)hChainEngine;
2279     PCertificateChain alternate;
2280
2281     TRACE("(%p, %p, %p, %p)\n", hChainEngine, pTime, hAdditionalStore, chain);
2282
2283     /* Always start with the last "lower quality" chain to ensure a consistent
2284      * order of alternate creation:
2285      */
2286     if (chain->context.cLowerQualityChainContext)
2287         chain = (PCertificateChain)chain->context.rgpLowerQualityChainContext[
2288          chain->context.cLowerQualityChainContext - 1];
2289     /* A chain with only one element can't have any alternates */
2290     if (chain->context.cChain <= 1 && chain->context.rgpChain[0]->cElement <= 1)
2291         alternate = NULL;
2292     else
2293     {
2294         DWORD i, j, infoStatus;
2295         PCCERT_CONTEXT alternateIssuer = NULL;
2296
2297         alternate = NULL;
2298         for (i = 0; !alternateIssuer && i < chain->context.cChain; i++)
2299             for (j = 0; !alternateIssuer &&
2300              j < chain->context.rgpChain[i]->cElement - 1; j++)
2301             {
2302                 PCCERT_CONTEXT subject =
2303                  chain->context.rgpChain[i]->rgpElement[j]->pCertContext;
2304                 PCCERT_CONTEXT prevIssuer = CertDuplicateCertificateContext(
2305                  chain->context.rgpChain[i]->rgpElement[j + 1]->pCertContext);
2306
2307                 alternateIssuer = CRYPT_GetIssuer(prevIssuer->hCertStore,
2308                  subject, prevIssuer, &infoStatus);
2309             }
2310         if (alternateIssuer)
2311         {
2312             i--;
2313             j--;
2314             alternate = CRYPT_CopyChainToElement(chain, i, j);
2315             if (alternate)
2316             {
2317                 BOOL ret = CRYPT_AddCertToSimpleChain(engine,
2318                  alternate->context.rgpChain[i], alternateIssuer, infoStatus);
2319
2320                 /* CRYPT_AddCertToSimpleChain add-ref's the issuer, so free it
2321                  * to close the enumeration that found it
2322                  */
2323                 CertFreeCertificateContext(alternateIssuer);
2324                 if (ret)
2325                 {
2326                     ret = CRYPT_BuildSimpleChain(engine, alternate->world,
2327                      alternate->context.rgpChain[i]);
2328                     if (ret)
2329                         CRYPT_CheckSimpleChain(engine,
2330                          alternate->context.rgpChain[i], pTime);
2331                     CRYPT_CombineTrustStatus(&alternate->context.TrustStatus,
2332                      &alternate->context.rgpChain[i]->TrustStatus);
2333                 }
2334                 if (!ret)
2335                 {
2336                     CRYPT_FreeChainContext(alternate);
2337                     alternate = NULL;
2338                 }
2339             }
2340         }
2341     }
2342     TRACE("%p\n", alternate);
2343     return alternate;
2344 }
2345
2346 #define CHAIN_QUALITY_SIGNATURE_VALID   0x16
2347 #define CHAIN_QUALITY_TIME_VALID        8
2348 #define CHAIN_QUALITY_COMPLETE_CHAIN    4
2349 #define CHAIN_QUALITY_BASIC_CONSTRAINTS 2
2350 #define CHAIN_QUALITY_TRUSTED_ROOT      1
2351
2352 #define CHAIN_QUALITY_HIGHEST \
2353  CHAIN_QUALITY_SIGNATURE_VALID | CHAIN_QUALITY_TIME_VALID | \
2354  CHAIN_QUALITY_COMPLETE_CHAIN | CHAIN_QUALITY_BASIC_CONSTRAINTS | \
2355  CHAIN_QUALITY_TRUSTED_ROOT
2356
2357 #define IS_TRUST_ERROR_SET(TrustStatus, bits) \
2358  (TrustStatus)->dwErrorStatus & (bits)
2359
2360 static DWORD CRYPT_ChainQuality(const CertificateChain *chain)
2361 {
2362     DWORD quality = CHAIN_QUALITY_HIGHEST;
2363
2364     if (IS_TRUST_ERROR_SET(&chain->context.TrustStatus,
2365      CERT_TRUST_IS_UNTRUSTED_ROOT))
2366         quality &= ~CHAIN_QUALITY_TRUSTED_ROOT;
2367     if (IS_TRUST_ERROR_SET(&chain->context.TrustStatus,
2368      CERT_TRUST_INVALID_BASIC_CONSTRAINTS))
2369         quality &= ~CHAIN_QUALITY_BASIC_CONSTRAINTS;
2370     if (IS_TRUST_ERROR_SET(&chain->context.TrustStatus,
2371      CERT_TRUST_IS_PARTIAL_CHAIN))
2372         quality &= ~CHAIN_QUALITY_COMPLETE_CHAIN;
2373     if (IS_TRUST_ERROR_SET(&chain->context.TrustStatus,
2374      CERT_TRUST_IS_NOT_TIME_VALID | CERT_TRUST_IS_NOT_TIME_NESTED))
2375         quality &= ~CHAIN_QUALITY_TIME_VALID;
2376     if (IS_TRUST_ERROR_SET(&chain->context.TrustStatus,
2377      CERT_TRUST_IS_NOT_SIGNATURE_VALID))
2378         quality &= ~CHAIN_QUALITY_SIGNATURE_VALID;
2379     return quality;
2380 }
2381
2382 /* Chooses the highest quality chain among chain and its "lower quality"
2383  * alternate chains.  Returns the highest quality chain, with all other
2384  * chains as lower quality chains of it.
2385  */
2386 static PCertificateChain CRYPT_ChooseHighestQualityChain(
2387  PCertificateChain chain)
2388 {
2389     DWORD i;
2390
2391     /* There are always only two chains being considered:  chain, and an
2392      * alternate at chain->rgpLowerQualityChainContext[i].  If the alternate
2393      * has a higher quality than chain, the alternate gets assigned the lower
2394      * quality contexts, with chain taking the alternate's place among the
2395      * lower quality contexts.
2396      */
2397     for (i = 0; i < chain->context.cLowerQualityChainContext; i++)
2398     {
2399         PCertificateChain alternate =
2400          (PCertificateChain)chain->context.rgpLowerQualityChainContext[i];
2401
2402         if (CRYPT_ChainQuality(alternate) > CRYPT_ChainQuality(chain))
2403         {
2404             alternate->context.cLowerQualityChainContext =
2405              chain->context.cLowerQualityChainContext;
2406             alternate->context.rgpLowerQualityChainContext =
2407              chain->context.rgpLowerQualityChainContext;
2408             alternate->context.rgpLowerQualityChainContext[i] =
2409              (PCCERT_CHAIN_CONTEXT)chain;
2410             chain->context.cLowerQualityChainContext = 0;
2411             chain->context.rgpLowerQualityChainContext = NULL;
2412             chain = alternate;
2413         }
2414     }
2415     return chain;
2416 }
2417
2418 static BOOL CRYPT_AddAlternateChainToChain(PCertificateChain chain,
2419  const CertificateChain *alternate)
2420 {
2421     BOOL ret;
2422
2423     if (chain->context.cLowerQualityChainContext)
2424         chain->context.rgpLowerQualityChainContext =
2425          CryptMemRealloc(chain->context.rgpLowerQualityChainContext,
2426          (chain->context.cLowerQualityChainContext + 1) *
2427          sizeof(PCCERT_CHAIN_CONTEXT));
2428     else
2429         chain->context.rgpLowerQualityChainContext =
2430          CryptMemAlloc(sizeof(PCCERT_CHAIN_CONTEXT));
2431     if (chain->context.rgpLowerQualityChainContext)
2432     {
2433         chain->context.rgpLowerQualityChainContext[
2434          chain->context.cLowerQualityChainContext++] =
2435          (PCCERT_CHAIN_CONTEXT)alternate;
2436         ret = TRUE;
2437     }
2438     else
2439         ret = FALSE;
2440     return ret;
2441 }
2442
2443 static PCERT_CHAIN_ELEMENT CRYPT_FindIthElementInChain(
2444  const CERT_CHAIN_CONTEXT *chain, DWORD i)
2445 {
2446     DWORD j, iElement;
2447     PCERT_CHAIN_ELEMENT element = NULL;
2448
2449     for (j = 0, iElement = 0; !element && j < chain->cChain; j++)
2450     {
2451         if (iElement + chain->rgpChain[j]->cElement < i)
2452             iElement += chain->rgpChain[j]->cElement;
2453         else
2454             element = chain->rgpChain[j]->rgpElement[i - iElement];
2455     }
2456     return element;
2457 }
2458
2459 typedef struct _CERT_CHAIN_PARA_NO_EXTRA_FIELDS {
2460     DWORD            cbSize;
2461     CERT_USAGE_MATCH RequestedUsage;
2462 } CERT_CHAIN_PARA_NO_EXTRA_FIELDS, *PCERT_CHAIN_PARA_NO_EXTRA_FIELDS;
2463
2464 static void CRYPT_VerifyChainRevocation(PCERT_CHAIN_CONTEXT chain,
2465  LPFILETIME pTime, const CERT_CHAIN_PARA *pChainPara, DWORD chainFlags)
2466 {
2467     DWORD cContext;
2468
2469     if (chainFlags & CERT_CHAIN_REVOCATION_CHECK_END_CERT)
2470         cContext = 1;
2471     else if ((chainFlags & CERT_CHAIN_REVOCATION_CHECK_CHAIN) ||
2472      (chainFlags & CERT_CHAIN_REVOCATION_CHECK_CHAIN_EXCLUDE_ROOT))
2473     {
2474         DWORD i;
2475
2476         for (i = 0, cContext = 0; i < chain->cChain; i++)
2477         {
2478             if (i < chain->cChain - 1 ||
2479              chainFlags & CERT_CHAIN_REVOCATION_CHECK_CHAIN)
2480                 cContext += chain->rgpChain[i]->cElement;
2481             else
2482                 cContext += chain->rgpChain[i]->cElement - 1;
2483         }
2484     }
2485     else
2486         cContext = 0;
2487     if (cContext)
2488     {
2489         PCCERT_CONTEXT *contexts =
2490          CryptMemAlloc(cContext * sizeof(PCCERT_CONTEXT));
2491
2492         if (contexts)
2493         {
2494             DWORD i, j, iContext, revocationFlags;
2495             CERT_REVOCATION_PARA revocationPara = { sizeof(revocationPara), 0 };
2496             CERT_REVOCATION_STATUS revocationStatus =
2497              { sizeof(revocationStatus), 0 };
2498             BOOL ret;
2499
2500             for (i = 0, iContext = 0; iContext < cContext && i < chain->cChain;
2501              i++)
2502             {
2503                 for (j = 0; iContext < cContext &&
2504                  j < chain->rgpChain[i]->cElement; j++)
2505                     contexts[iContext++] =
2506                      chain->rgpChain[i]->rgpElement[j]->pCertContext;
2507             }
2508             revocationFlags = CERT_VERIFY_REV_CHAIN_FLAG;
2509             if (chainFlags & CERT_CHAIN_REVOCATION_CHECK_CACHE_ONLY)
2510                 revocationFlags |= CERT_VERIFY_CACHE_ONLY_BASED_REVOCATION;
2511             if (chainFlags & CERT_CHAIN_REVOCATION_ACCUMULATIVE_TIMEOUT)
2512                 revocationFlags |= CERT_VERIFY_REV_ACCUMULATIVE_TIMEOUT_FLAG;
2513             revocationPara.pftTimeToUse = pTime;
2514             if (pChainPara->cbSize == sizeof(CERT_CHAIN_PARA))
2515             {
2516                 revocationPara.dwUrlRetrievalTimeout =
2517                  pChainPara->dwUrlRetrievalTimeout;
2518                 revocationPara.fCheckFreshnessTime =
2519                  pChainPara->fCheckRevocationFreshnessTime;
2520                 revocationPara.dwFreshnessTime =
2521                  pChainPara->dwRevocationFreshnessTime;
2522             }
2523             ret = CertVerifyRevocation(X509_ASN_ENCODING,
2524              CERT_CONTEXT_REVOCATION_TYPE, cContext, (void **)contexts,
2525              revocationFlags, &revocationPara, &revocationStatus);
2526             if (!ret)
2527             {
2528                 PCERT_CHAIN_ELEMENT element =
2529                  CRYPT_FindIthElementInChain(chain, revocationStatus.dwIndex);
2530                 DWORD error;
2531
2532                 switch (revocationStatus.dwError)
2533                 {
2534                 case CRYPT_E_NO_REVOCATION_CHECK:
2535                 case CRYPT_E_NO_REVOCATION_DLL:
2536                 case CRYPT_E_NOT_IN_REVOCATION_DATABASE:
2537                     /* If the revocation status is unknown, it's assumed to be
2538                      * offline too.
2539                      */
2540                     error = CERT_TRUST_REVOCATION_STATUS_UNKNOWN |
2541                      CERT_TRUST_IS_OFFLINE_REVOCATION;
2542                     break;
2543                 case CRYPT_E_REVOCATION_OFFLINE:
2544                     error = CERT_TRUST_IS_OFFLINE_REVOCATION;
2545                     break;
2546                 case CRYPT_E_REVOKED:
2547                     error = CERT_TRUST_IS_REVOKED;
2548                     break;
2549                 default:
2550                     WARN("unmapped error %08x\n", revocationStatus.dwError);
2551                     error = 0;
2552                 }
2553                 if (element)
2554                 {
2555                     /* FIXME: set element's pRevocationInfo member */
2556                     element->TrustStatus.dwErrorStatus |= error;
2557                 }
2558                 chain->TrustStatus.dwErrorStatus |= error;
2559             }
2560             CryptMemFree(contexts);
2561         }
2562     }
2563 }
2564
2565 static void CRYPT_CheckUsages(PCERT_CHAIN_CONTEXT chain,
2566  const CERT_CHAIN_PARA *pChainPara)
2567 {
2568     if (pChainPara->cbSize >= sizeof(CERT_CHAIN_PARA_NO_EXTRA_FIELDS) &&
2569      pChainPara->RequestedUsage.Usage.cUsageIdentifier)
2570     {
2571         PCCERT_CONTEXT endCert;
2572         PCERT_EXTENSION ext;
2573         BOOL validForUsage;
2574
2575         /* A chain, if created, always includes the end certificate */
2576         endCert = chain->rgpChain[0]->rgpElement[0]->pCertContext;
2577         /* The extended key usage extension specifies how a certificate's
2578          * public key may be used.  From RFC 5280, section 4.2.1.12:
2579          * "This extension indicates one or more purposes for which the
2580          *  certified public key may be used, in addition to or in place of the
2581          *  basic purposes indicated in the key usage extension."
2582          * If the extension is present, it only satisfies the requested usage
2583          * if that usage is included in the extension:
2584          * "If the extension is present, then the certificate MUST only be used
2585          *  for one of the purposes indicated."
2586          * There is also the special anyExtendedKeyUsage OID, but it doesn't
2587          * have to be respected:
2588          * "Applications that require the presence of a particular purpose
2589          *  MAY reject certificates that include the anyExtendedKeyUsage OID
2590          *  but not the particular OID expected for the application."
2591          * For now, I'm being more conservative and ignoring the presence of
2592          * the anyExtendedKeyUsage OID.
2593          */
2594         if ((ext = CertFindExtension(szOID_ENHANCED_KEY_USAGE,
2595          endCert->pCertInfo->cExtension, endCert->pCertInfo->rgExtension)))
2596         {
2597             const CERT_ENHKEY_USAGE *requestedUsage =
2598              &pChainPara->RequestedUsage.Usage;
2599             CERT_ENHKEY_USAGE *usage;
2600             DWORD size;
2601
2602             if (CryptDecodeObjectEx(X509_ASN_ENCODING,
2603              X509_ENHANCED_KEY_USAGE, ext->Value.pbData, ext->Value.cbData,
2604              CRYPT_DECODE_ALLOC_FLAG, NULL, &usage, &size))
2605             {
2606                 if (pChainPara->RequestedUsage.dwType == USAGE_MATCH_TYPE_AND)
2607                 {
2608                     DWORD i, j;
2609
2610                     /* For AND matches, all usages must be present */
2611                     validForUsage = TRUE;
2612                     for (i = 0; validForUsage &&
2613                      i < requestedUsage->cUsageIdentifier; i++)
2614                     {
2615                         BOOL match = FALSE;
2616
2617                         for (j = 0; !match && j < usage->cUsageIdentifier; j++)
2618                             match = !strcmp(usage->rgpszUsageIdentifier[j],
2619                              requestedUsage->rgpszUsageIdentifier[i]);
2620                         if (!match)
2621                             validForUsage = FALSE;
2622                     }
2623                 }
2624                 else
2625                 {
2626                     DWORD i, j;
2627
2628                     /* For OR matches, any matching usage suffices */
2629                     validForUsage = FALSE;
2630                     for (i = 0; !validForUsage &&
2631                      i < requestedUsage->cUsageIdentifier; i++)
2632                     {
2633                         for (j = 0; !validForUsage &&
2634                          j < usage->cUsageIdentifier; j++)
2635                             validForUsage =
2636                              !strcmp(usage->rgpszUsageIdentifier[j],
2637                              requestedUsage->rgpszUsageIdentifier[i]);
2638                     }
2639                 }
2640                 LocalFree(usage);
2641             }
2642             else
2643                 validForUsage = FALSE;
2644         }
2645         else
2646         {
2647             /* If the extension isn't present, any interpretation is valid:
2648              * "Certificate using applications MAY require that the extended
2649              *  key usage extension be present and that a particular purpose
2650              *  be indicated in order for the certificate to be acceptable to
2651              *  that application."
2652              * Not all web sites include the extended key usage extension, so
2653              * accept chains without it.
2654              */
2655             TRACE_(chain)("requested usage from certificate with no usages\n");
2656             validForUsage = TRUE;
2657         }
2658         if (!validForUsage)
2659         {
2660             chain->TrustStatus.dwErrorStatus |=
2661              CERT_TRUST_IS_NOT_VALID_FOR_USAGE;
2662             chain->rgpChain[0]->rgpElement[0]->TrustStatus.dwErrorStatus |=
2663              CERT_TRUST_IS_NOT_VALID_FOR_USAGE;
2664         }
2665     }
2666     if (pChainPara->cbSize >= sizeof(CERT_CHAIN_PARA) &&
2667      pChainPara->RequestedIssuancePolicy.Usage.cUsageIdentifier)
2668         FIXME("unimplemented for RequestedIssuancePolicy\n");
2669 }
2670
2671 static void dump_usage_match(LPCSTR name, const CERT_USAGE_MATCH *usageMatch)
2672 {
2673     if (usageMatch->Usage.cUsageIdentifier)
2674     {
2675         DWORD i;
2676
2677         TRACE_(chain)("%s: %s\n", name,
2678          usageMatch->dwType == USAGE_MATCH_TYPE_AND ? "AND" : "OR");
2679         for (i = 0; i < usageMatch->Usage.cUsageIdentifier; i++)
2680             TRACE_(chain)("%s\n", usageMatch->Usage.rgpszUsageIdentifier[i]);
2681     }
2682 }
2683
2684 static void dump_chain_para(const CERT_CHAIN_PARA *pChainPara)
2685 {
2686     TRACE_(chain)("%d\n", pChainPara->cbSize);
2687     if (pChainPara->cbSize >= sizeof(CERT_CHAIN_PARA_NO_EXTRA_FIELDS))
2688         dump_usage_match("RequestedUsage", &pChainPara->RequestedUsage);
2689     if (pChainPara->cbSize >= sizeof(CERT_CHAIN_PARA))
2690     {
2691         dump_usage_match("RequestedIssuancePolicy",
2692          &pChainPara->RequestedIssuancePolicy);
2693         TRACE_(chain)("%d\n", pChainPara->dwUrlRetrievalTimeout);
2694         TRACE_(chain)("%d\n", pChainPara->fCheckRevocationFreshnessTime);
2695         TRACE_(chain)("%d\n", pChainPara->dwRevocationFreshnessTime);
2696     }
2697 }
2698
2699 BOOL WINAPI CertGetCertificateChain(HCERTCHAINENGINE hChainEngine,
2700  PCCERT_CONTEXT pCertContext, LPFILETIME pTime, HCERTSTORE hAdditionalStore,
2701  PCERT_CHAIN_PARA pChainPara, DWORD dwFlags, LPVOID pvReserved,
2702  PCCERT_CHAIN_CONTEXT* ppChainContext)
2703 {
2704     BOOL ret;
2705     PCertificateChain chain = NULL;
2706
2707     TRACE("(%p, %p, %p, %p, %p, %08x, %p, %p)\n", hChainEngine, pCertContext,
2708      pTime, hAdditionalStore, pChainPara, dwFlags, pvReserved, ppChainContext);
2709
2710     if (ppChainContext)
2711         *ppChainContext = NULL;
2712     if (!pChainPara)
2713     {
2714         SetLastError(E_INVALIDARG);
2715         return FALSE;
2716     }
2717     if (!pCertContext->pCertInfo->SignatureAlgorithm.pszObjId)
2718     {
2719         SetLastError(ERROR_INVALID_DATA);
2720         return FALSE;
2721     }
2722
2723     if (!hChainEngine)
2724         hChainEngine = CRYPT_GetDefaultChainEngine();
2725     if (TRACE_ON(chain))
2726         dump_chain_para(pChainPara);
2727     /* FIXME: what about HCCE_LOCAL_MACHINE? */
2728     ret = CRYPT_BuildCandidateChainFromCert(hChainEngine, pCertContext, pTime,
2729      hAdditionalStore, &chain);
2730     if (ret)
2731     {
2732         PCertificateChain alternate = NULL;
2733         PCERT_CHAIN_CONTEXT pChain;
2734
2735         do {
2736             alternate = CRYPT_BuildAlternateContextFromChain(hChainEngine,
2737              pTime, hAdditionalStore, chain);
2738
2739             /* Alternate contexts are added as "lower quality" contexts of
2740              * chain, to avoid loops in alternate chain creation.
2741              * The highest-quality chain is chosen at the end.
2742              */
2743             if (alternate)
2744                 ret = CRYPT_AddAlternateChainToChain(chain, alternate);
2745         } while (ret && alternate);
2746         chain = CRYPT_ChooseHighestQualityChain(chain);
2747         if (!(dwFlags & CERT_CHAIN_RETURN_LOWER_QUALITY_CONTEXTS))
2748             CRYPT_FreeLowerQualityChains(chain);
2749         pChain = (PCERT_CHAIN_CONTEXT)chain;
2750         if (!pChain->TrustStatus.dwErrorStatus)
2751             CRYPT_VerifyChainRevocation(pChain, pTime, pChainPara, dwFlags);
2752         CRYPT_CheckUsages(pChain, pChainPara);
2753         TRACE_(chain)("error status: %08x\n",
2754          pChain->TrustStatus.dwErrorStatus);
2755         if (ppChainContext)
2756             *ppChainContext = pChain;
2757         else
2758             CertFreeCertificateChain(pChain);
2759     }
2760     TRACE("returning %d\n", ret);
2761     return ret;
2762 }
2763
2764 PCCERT_CHAIN_CONTEXT WINAPI CertDuplicateCertificateChain(
2765  PCCERT_CHAIN_CONTEXT pChainContext)
2766 {
2767     PCertificateChain chain = (PCertificateChain)pChainContext;
2768
2769     TRACE("(%p)\n", pChainContext);
2770
2771     if (chain)
2772         InterlockedIncrement(&chain->ref);
2773     return pChainContext;
2774 }
2775
2776 VOID WINAPI CertFreeCertificateChain(PCCERT_CHAIN_CONTEXT pChainContext)
2777 {
2778     PCertificateChain chain = (PCertificateChain)pChainContext;
2779
2780     TRACE("(%p)\n", pChainContext);
2781
2782     if (chain)
2783     {
2784         if (InterlockedDecrement(&chain->ref) == 0)
2785             CRYPT_FreeChainContext(chain);
2786     }
2787 }
2788
2789 static void find_element_with_error(PCCERT_CHAIN_CONTEXT chain, DWORD error,
2790  LONG *iChain, LONG *iElement)
2791 {
2792     DWORD i, j;
2793
2794     for (i = 0; i < chain->cChain; i++)
2795         for (j = 0; j < chain->rgpChain[i]->cElement; j++)
2796             if (chain->rgpChain[i]->rgpElement[j]->TrustStatus.dwErrorStatus &
2797              error)
2798             {
2799                 *iChain = i;
2800                 *iElement = j;
2801                 return;
2802             }
2803 }
2804
2805 static BOOL WINAPI verify_base_policy(LPCSTR szPolicyOID,
2806  PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
2807  PCERT_CHAIN_POLICY_STATUS pPolicyStatus)
2808 {
2809     pPolicyStatus->lChainIndex = pPolicyStatus->lElementIndex = -1;
2810     if (pChainContext->TrustStatus.dwErrorStatus &
2811      CERT_TRUST_IS_NOT_SIGNATURE_VALID)
2812     {
2813         pPolicyStatus->dwError = TRUST_E_CERT_SIGNATURE;
2814         find_element_with_error(pChainContext,
2815          CERT_TRUST_IS_NOT_SIGNATURE_VALID, &pPolicyStatus->lChainIndex,
2816          &pPolicyStatus->lElementIndex);
2817     }
2818     else if (pChainContext->TrustStatus.dwErrorStatus &
2819      CERT_TRUST_IS_UNTRUSTED_ROOT)
2820     {
2821         pPolicyStatus->dwError = CERT_E_UNTRUSTEDROOT;
2822         find_element_with_error(pChainContext,
2823          CERT_TRUST_IS_UNTRUSTED_ROOT, &pPolicyStatus->lChainIndex,
2824          &pPolicyStatus->lElementIndex);
2825     }
2826     else if (pChainContext->TrustStatus.dwErrorStatus & CERT_TRUST_IS_CYCLIC)
2827     {
2828         pPolicyStatus->dwError = CERT_E_CHAINING;
2829         find_element_with_error(pChainContext, CERT_TRUST_IS_CYCLIC,
2830          &pPolicyStatus->lChainIndex, &pPolicyStatus->lElementIndex);
2831         /* For a cyclic chain, which element is a cycle isn't meaningful */
2832         pPolicyStatus->lElementIndex = -1;
2833     }
2834     else
2835         pPolicyStatus->dwError = NO_ERROR;
2836     return TRUE;
2837 }
2838
2839 static BYTE msTestPubKey1[] = {
2840 0x30,0x47,0x02,0x40,0x81,0x55,0x22,0xb9,0x8a,0xa4,0x6f,0xed,0xd6,0xe7,0xd9,
2841 0x66,0x0f,0x55,0xbc,0xd7,0xcd,0xd5,0xbc,0x4e,0x40,0x02,0x21,0xa2,0xb1,0xf7,
2842 0x87,0x30,0x85,0x5e,0xd2,0xf2,0x44,0xb9,0xdc,0x9b,0x75,0xb6,0xfb,0x46,0x5f,
2843 0x42,0xb6,0x9d,0x23,0x36,0x0b,0xde,0x54,0x0f,0xcd,0xbd,0x1f,0x99,0x2a,0x10,
2844 0x58,0x11,0xcb,0x40,0xcb,0xb5,0xa7,0x41,0x02,0x03,0x01,0x00,0x01 };
2845 static BYTE msTestPubKey2[] = {
2846 0x30,0x47,0x02,0x40,0x9c,0x50,0x05,0x1d,0xe2,0x0e,0x4c,0x53,0xd8,0xd9,0xb5,
2847 0xe5,0xfd,0xe9,0xe3,0xad,0x83,0x4b,0x80,0x08,0xd9,0xdc,0xe8,0xe8,0x35,0xf8,
2848 0x11,0xf1,0xe9,0x9b,0x03,0x7a,0x65,0x64,0x76,0x35,0xce,0x38,0x2c,0xf2,0xb6,
2849 0x71,0x9e,0x06,0xd9,0xbf,0xbb,0x31,0x69,0xa3,0xf6,0x30,0xa0,0x78,0x7b,0x18,
2850 0xdd,0x50,0x4d,0x79,0x1e,0xeb,0x61,0xc1,0x02,0x03,0x01,0x00,0x01 };
2851
2852 static BOOL WINAPI verify_authenticode_policy(LPCSTR szPolicyOID,
2853  PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
2854  PCERT_CHAIN_POLICY_STATUS pPolicyStatus)
2855 {
2856     BOOL ret = verify_base_policy(szPolicyOID, pChainContext, pPolicyPara,
2857      pPolicyStatus);
2858
2859     if (ret && pPolicyStatus->dwError == CERT_E_UNTRUSTEDROOT)
2860     {
2861         CERT_PUBLIC_KEY_INFO msPubKey = { { 0 } };
2862         BOOL isMSTestRoot = FALSE;
2863         PCCERT_CONTEXT failingCert =
2864          pChainContext->rgpChain[pPolicyStatus->lChainIndex]->
2865          rgpElement[pPolicyStatus->lElementIndex]->pCertContext;
2866         DWORD i;
2867         CRYPT_DATA_BLOB keyBlobs[] = {
2868          { sizeof(msTestPubKey1), msTestPubKey1 },
2869          { sizeof(msTestPubKey2), msTestPubKey2 },
2870         };
2871
2872         /* Check whether the root is an MS test root */
2873         for (i = 0; !isMSTestRoot && i < sizeof(keyBlobs) / sizeof(keyBlobs[0]);
2874          i++)
2875         {
2876             msPubKey.PublicKey.cbData = keyBlobs[i].cbData;
2877             msPubKey.PublicKey.pbData = keyBlobs[i].pbData;
2878             if (CertComparePublicKeyInfo(
2879              X509_ASN_ENCODING | PKCS_7_ASN_ENCODING,
2880              &failingCert->pCertInfo->SubjectPublicKeyInfo, &msPubKey))
2881                 isMSTestRoot = TRUE;
2882         }
2883         if (isMSTestRoot)
2884             pPolicyStatus->dwError = CERT_E_UNTRUSTEDTESTROOT;
2885     }
2886     return ret;
2887 }
2888
2889 static BOOL WINAPI verify_basic_constraints_policy(LPCSTR szPolicyOID,
2890  PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
2891  PCERT_CHAIN_POLICY_STATUS pPolicyStatus)
2892 {
2893     pPolicyStatus->lChainIndex = pPolicyStatus->lElementIndex = -1;
2894     if (pChainContext->TrustStatus.dwErrorStatus &
2895      CERT_TRUST_INVALID_BASIC_CONSTRAINTS)
2896     {
2897         pPolicyStatus->dwError = TRUST_E_BASIC_CONSTRAINTS;
2898         find_element_with_error(pChainContext,
2899          CERT_TRUST_INVALID_BASIC_CONSTRAINTS, &pPolicyStatus->lChainIndex,
2900          &pPolicyStatus->lElementIndex);
2901     }
2902     else
2903         pPolicyStatus->dwError = NO_ERROR;
2904     return TRUE;
2905 }
2906
2907 static BOOL match_dns_to_subject_alt_name(PCERT_EXTENSION ext,
2908  LPCWSTR server_name)
2909 {
2910     BOOL matches = FALSE;
2911     CERT_ALT_NAME_INFO *subjectName;
2912     DWORD size;
2913
2914     TRACE_(chain)("%s\n", debugstr_w(server_name));
2915     /* This could be spoofed by the embedded NULL vulnerability, since the
2916      * returned CERT_ALT_NAME_INFO doesn't have a way to indicate the
2917      * encoded length of a name.  Fortunately CryptDecodeObjectEx fails if
2918      * the encoded form of the name contains a NULL.
2919      */
2920     if (CryptDecodeObjectEx(X509_ASN_ENCODING, X509_ALTERNATE_NAME,
2921      ext->Value.pbData, ext->Value.cbData,
2922      CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG, NULL,
2923      &subjectName, &size))
2924     {
2925         DWORD i;
2926
2927         /* RFC 5280 states that multiple instances of each name type may exist,
2928          * in section 4.2.1.6:
2929          * "Multiple name forms, and multiple instances of each name form,
2930          *  MAY be included."
2931          * It doesn't specify the behavior in such cases, but both RFC 2818
2932          * and RFC 2595 explicitly accept a certificate if any name matches.
2933          */
2934         for (i = 0; !matches && i < subjectName->cAltEntry; i++)
2935         {
2936             if (subjectName->rgAltEntry[i].dwAltNameChoice ==
2937              CERT_ALT_NAME_DNS_NAME)
2938             {
2939                 TRACE_(chain)("dNSName: %s\n", debugstr_w(
2940                  subjectName->rgAltEntry[i].u.pwszDNSName));
2941                 if (!strcmpiW(server_name,
2942                  subjectName->rgAltEntry[i].u.pwszDNSName))
2943                     matches = TRUE;
2944             }
2945         }
2946         LocalFree(subjectName);
2947     }
2948     return matches;
2949 }
2950
2951 static BOOL find_matching_domain_component(CERT_NAME_INFO *name,
2952  LPCWSTR component)
2953 {
2954     BOOL matches = FALSE;
2955     DWORD i, j;
2956
2957     for (i = 0; !matches && i < name->cRDN; i++)
2958         for (j = 0; j < name->rgRDN[i].cRDNAttr; j++)
2959             if (!strcmp(szOID_DOMAIN_COMPONENT,
2960              name->rgRDN[i].rgRDNAttr[j].pszObjId))
2961             {
2962                 PCERT_RDN_ATTR attr;
2963
2964                 attr = &name->rgRDN[i].rgRDNAttr[j];
2965                 /* Compare with memicmpW rather than strcmpiW in order to avoid
2966                  * a match with a string with an embedded NULL.  The component
2967                  * must match one domain component attribute's entire string
2968                  * value with a case-insensitive match.
2969                  */
2970                 matches = !memicmpW(component, (LPWSTR)attr->Value.pbData,
2971                  attr->Value.cbData / sizeof(WCHAR));
2972             }
2973     return matches;
2974 }
2975
2976 static BOOL match_domain_component(LPCWSTR allowed_component, DWORD allowed_len,
2977  LPCWSTR server_component, DWORD server_len, BOOL allow_wildcards,
2978  BOOL *see_wildcard)
2979 {
2980     LPCWSTR allowed_ptr, server_ptr;
2981     BOOL matches = TRUE;
2982
2983     *see_wildcard = FALSE;
2984     if (server_len < allowed_len)
2985     {
2986         WARN_(chain)("domain component %s too short for %s\n",
2987          debugstr_wn(server_component, server_len),
2988          debugstr_wn(allowed_component, allowed_len));
2989         /* A domain component can't contain a wildcard character, so a domain
2990          * component shorter than the allowed string can't produce a match.
2991          */
2992         return FALSE;
2993     }
2994     for (allowed_ptr = allowed_component, server_ptr = server_component;
2995          matches && allowed_ptr - allowed_component < allowed_len;
2996          allowed_ptr++, server_ptr++)
2997     {
2998         if (*allowed_ptr == '*')
2999         {
3000             if (allowed_ptr - allowed_component < allowed_len - 1)
3001             {
3002                 WARN_(chain)("non-wildcard characters after wildcard not supported\n");
3003                 matches = FALSE;
3004             }
3005             else if (!allow_wildcards)
3006             {
3007                 WARN_(chain)("wildcard after non-wildcard component\n");
3008                 matches = FALSE;
3009             }
3010             else
3011             {
3012                 /* the preceding characters must have matched, so the rest of
3013                  * the component also matches.
3014                  */
3015                 *see_wildcard = TRUE;
3016                 break;
3017             }
3018         }
3019         matches = tolowerW(*allowed_ptr) == tolowerW(*server_ptr);
3020     }
3021     if (matches && server_ptr - server_component < server_len)
3022     {
3023         /* If there are unmatched characters in the server domain component,
3024          * the server domain only matches if the allowed string ended in a '*'.
3025          */
3026         matches = *allowed_ptr == '*';
3027     }
3028     return matches;
3029 }
3030
3031 static BOOL match_common_name(LPCWSTR server_name, PCERT_RDN_ATTR nameAttr)
3032 {
3033     LPCWSTR allowed = (LPCWSTR)nameAttr->Value.pbData;
3034     LPCWSTR allowed_component = allowed;
3035     DWORD allowed_len = nameAttr->Value.cbData / sizeof(WCHAR);
3036     LPCWSTR server_component = server_name;
3037     DWORD server_len = strlenW(server_name);
3038     BOOL matches = TRUE, allow_wildcards = TRUE;
3039
3040     TRACE_(chain)("CN = %s\n", debugstr_wn(allowed_component, allowed_len));
3041
3042     /* From RFC 2818 (HTTP over TLS), section 3.1:
3043      * "Names may contain the wildcard character * which is considered to match
3044      *  any single domain name component or component fragment. E.g.,
3045      *  *.a.com matches foo.a.com but not bar.foo.a.com. f*.com matches foo.com
3046      *  but not bar.com."
3047      *
3048      * And from RFC 2595 (Using TLS with IMAP, POP3 and ACAP), section 2.4:
3049      * "A "*" wildcard character MAY be used as the left-most name component in
3050      *  the certificate.  For example, *.example.com would match a.example.com,
3051      *  foo.example.com, etc. but would not match example.com."
3052      *
3053      * There are other protocols which use TLS, and none of them is
3054      * authoritative.  This accepts certificates in common usage, e.g.
3055      * *.domain.com matches www.domain.com but not domain.com, and
3056      * www*.domain.com matches www1.domain.com but not mail.domain.com.
3057      */
3058     do {
3059         LPCWSTR allowed_dot, server_dot;
3060
3061         allowed_dot = memchrW(allowed_component, '.',
3062          allowed_len - (allowed_component - allowed));
3063         server_dot = memchrW(server_component, '.',
3064          server_len - (server_component - server_name));
3065         /* The number of components must match */
3066         if ((!allowed_dot && server_dot) || (allowed_dot && !server_dot))
3067         {
3068             if (!allowed_dot)
3069                 WARN_(chain)("%s: too many components for CN=%s\n",
3070                  debugstr_w(server_name), debugstr_wn(allowed, allowed_len));
3071             else
3072                 WARN_(chain)("%s: not enough components for CN=%s\n",
3073                  debugstr_w(server_name), debugstr_wn(allowed, allowed_len));
3074             matches = FALSE;
3075         }
3076         else
3077         {
3078             LPCWSTR allowed_end, server_end;
3079             BOOL has_wildcard;
3080
3081             allowed_end = allowed_dot ? allowed_dot : allowed + allowed_len;
3082             server_end = server_dot ? server_dot : server_name + server_len;
3083             matches = match_domain_component(allowed_component,
3084              allowed_end - allowed_component, server_component,
3085              server_end - server_component, allow_wildcards, &has_wildcard);
3086             /* Once a non-wildcard component is seen, no wildcard components
3087              * may follow
3088              */
3089             if (!has_wildcard)
3090                 allow_wildcards = FALSE;
3091             if (matches)
3092             {
3093                 allowed_component = allowed_dot ? allowed_dot + 1 : allowed_end;
3094                 server_component = server_dot ? server_dot + 1 : server_end;
3095             }
3096         }
3097     } while (matches && allowed_component &&
3098      allowed_component - allowed < allowed_len &&
3099      server_component && server_component - server_name < server_len);
3100     TRACE_(chain)("returning %d\n", matches);
3101     return matches;
3102 }
3103
3104 static BOOL match_dns_to_subject_dn(PCCERT_CONTEXT cert, LPCWSTR server_name)
3105 {
3106     BOOL matches = FALSE;
3107     CERT_NAME_INFO *name;
3108     DWORD size;
3109
3110     TRACE_(chain)("%s\n", debugstr_w(server_name));
3111     if (CryptDecodeObjectEx(X509_ASN_ENCODING, X509_UNICODE_NAME,
3112      cert->pCertInfo->Subject.pbData, cert->pCertInfo->Subject.cbData,
3113      CRYPT_DECODE_ALLOC_FLAG | CRYPT_DECODE_NOCOPY_FLAG, NULL,
3114      &name, &size))
3115     {
3116         /* If the subject distinguished name contains any name components,
3117          * make sure all of them are present.
3118          */
3119         if (CertFindRDNAttr(szOID_DOMAIN_COMPONENT, name))
3120         {
3121             LPCWSTR ptr = server_name;
3122
3123             matches = TRUE;
3124             do {
3125                 LPCWSTR dot = strchrW(ptr, '.'), end;
3126                 /* 254 is the maximum DNS label length, see RFC 1035 */
3127                 WCHAR component[255];
3128                 DWORD len;
3129
3130                 end = dot ? dot : ptr + strlenW(ptr);
3131                 len = end - ptr;
3132                 if (len >= sizeof(component) / sizeof(component[0]))
3133                 {
3134                     WARN_(chain)("domain component %s too long\n",
3135                      debugstr_wn(ptr, len));
3136                     matches = FALSE;
3137                 }
3138                 else
3139                 {
3140                     memcpy(component, ptr, len * sizeof(WCHAR));
3141                     component[len] = 0;
3142                     matches = find_matching_domain_component(name, component);
3143                 }
3144                 ptr = dot ? dot + 1 : end;
3145             } while (matches && ptr && *ptr);
3146         }
3147         else
3148         {
3149             PCERT_RDN_ATTR attr;
3150
3151             /* If the certificate isn't using a DN attribute in the name, make
3152              * make sure the common name matches.
3153              */
3154             if ((attr = CertFindRDNAttr(szOID_COMMON_NAME, name)))
3155                 matches = match_common_name(server_name, attr);
3156         }
3157         LocalFree(name);
3158     }
3159     return matches;
3160 }
3161
3162 static BOOL WINAPI verify_ssl_policy(LPCSTR szPolicyOID,
3163  PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
3164  PCERT_CHAIN_POLICY_STATUS pPolicyStatus)
3165 {
3166     pPolicyStatus->lChainIndex = pPolicyStatus->lElementIndex = -1;
3167     if (pChainContext->TrustStatus.dwErrorStatus &
3168      CERT_TRUST_IS_NOT_SIGNATURE_VALID)
3169     {
3170         pPolicyStatus->dwError = TRUST_E_CERT_SIGNATURE;
3171         find_element_with_error(pChainContext,
3172          CERT_TRUST_IS_NOT_SIGNATURE_VALID, &pPolicyStatus->lChainIndex,
3173          &pPolicyStatus->lElementIndex);
3174     }
3175     else if (pChainContext->TrustStatus.dwErrorStatus &
3176      CERT_TRUST_IS_UNTRUSTED_ROOT)
3177     {
3178         pPolicyStatus->dwError = CERT_E_UNTRUSTEDROOT;
3179         find_element_with_error(pChainContext,
3180          CERT_TRUST_IS_UNTRUSTED_ROOT, &pPolicyStatus->lChainIndex,
3181          &pPolicyStatus->lElementIndex);
3182     }
3183     else if (pChainContext->TrustStatus.dwErrorStatus & CERT_TRUST_IS_CYCLIC)
3184     {
3185         pPolicyStatus->dwError = CERT_E_UNTRUSTEDROOT;
3186         find_element_with_error(pChainContext,
3187          CERT_TRUST_IS_CYCLIC, &pPolicyStatus->lChainIndex,
3188          &pPolicyStatus->lElementIndex);
3189         /* For a cyclic chain, which element is a cycle isn't meaningful */
3190         pPolicyStatus->lElementIndex = -1;
3191     }
3192     else if (pChainContext->TrustStatus.dwErrorStatus &
3193      CERT_TRUST_IS_NOT_TIME_VALID)
3194     {
3195         pPolicyStatus->dwError = CERT_E_EXPIRED;
3196         find_element_with_error(pChainContext,
3197          CERT_TRUST_IS_NOT_TIME_VALID, &pPolicyStatus->lChainIndex,
3198          &pPolicyStatus->lElementIndex);
3199     }
3200     else
3201         pPolicyStatus->dwError = NO_ERROR;
3202     /* We only need bother checking whether the name in the end certificate
3203      * matches if the chain is otherwise okay.
3204      */
3205     if (!pPolicyStatus->dwError && pPolicyPara &&
3206      pPolicyPara->cbSize >= sizeof(CERT_CHAIN_POLICY_PARA))
3207     {
3208         HTTPSPolicyCallbackData *sslPara = pPolicyPara->pvExtraPolicyPara;
3209
3210         if (sslPara && sslPara->u.cbSize >= sizeof(HTTPSPolicyCallbackData))
3211         {
3212             if (sslPara->dwAuthType == AUTHTYPE_SERVER &&
3213              sslPara->pwszServerName)
3214             {
3215                 PCCERT_CONTEXT cert;
3216                 PCERT_EXTENSION altNameExt;
3217                 BOOL matches;
3218
3219                 cert = pChainContext->rgpChain[0]->rgpElement[0]->pCertContext;
3220                 altNameExt = get_subject_alt_name_ext(cert->pCertInfo);
3221                 /* If the alternate name extension exists, the name it contains
3222                  * is bound to the certificate, so make sure the name matches
3223                  * it.  Otherwise, look for the server name in the subject
3224                  * distinguished name.  RFC5280, section 4.2.1.6:
3225                  * "Whenever such identities are to be bound into a
3226                  *  certificate, the subject alternative name (or issuer
3227                  *  alternative name) extension MUST be used; however, a DNS
3228                  *  name MAY also be represented in the subject field using the
3229                  *  domainComponent attribute."
3230                  */
3231                 if (altNameExt)
3232                     matches = match_dns_to_subject_alt_name(altNameExt,
3233                      sslPara->pwszServerName);
3234                 else
3235                     matches = match_dns_to_subject_dn(cert,
3236                      sslPara->pwszServerName);
3237                 if (!matches)
3238                 {
3239                     pPolicyStatus->dwError = CERT_E_CN_NO_MATCH;
3240                     pPolicyStatus->lChainIndex = 0;
3241                     pPolicyStatus->lElementIndex = 0;
3242                 }
3243             }
3244         }
3245     }
3246     return TRUE;
3247 }
3248
3249 static BYTE msPubKey1[] = {
3250 0x30,0x82,0x01,0x0a,0x02,0x82,0x01,0x01,0x00,0xdf,0x08,0xba,0xe3,0x3f,0x6e,
3251 0x64,0x9b,0xf5,0x89,0xaf,0x28,0x96,0x4a,0x07,0x8f,0x1b,0x2e,0x8b,0x3e,0x1d,
3252 0xfc,0xb8,0x80,0x69,0xa3,0xa1,0xce,0xdb,0xdf,0xb0,0x8e,0x6c,0x89,0x76,0x29,
3253 0x4f,0xca,0x60,0x35,0x39,0xad,0x72,0x32,0xe0,0x0b,0xae,0x29,0x3d,0x4c,0x16,
3254 0xd9,0x4b,0x3c,0x9d,0xda,0xc5,0xd3,0xd1,0x09,0xc9,0x2c,0x6f,0xa6,0xc2,0x60,
3255 0x53,0x45,0xdd,0x4b,0xd1,0x55,0xcd,0x03,0x1c,0xd2,0x59,0x56,0x24,0xf3,0xe5,
3256 0x78,0xd8,0x07,0xcc,0xd8,0xb3,0x1f,0x90,0x3f,0xc0,0x1a,0x71,0x50,0x1d,0x2d,
3257 0xa7,0x12,0x08,0x6d,0x7c,0xb0,0x86,0x6c,0xc7,0xba,0x85,0x32,0x07,0xe1,0x61,
3258 0x6f,0xaf,0x03,0xc5,0x6d,0xe5,0xd6,0xa1,0x8f,0x36,0xf6,0xc1,0x0b,0xd1,0x3e,
3259 0x69,0x97,0x48,0x72,0xc9,0x7f,0xa4,0xc8,0xc2,0x4a,0x4c,0x7e,0xa1,0xd1,0x94,
3260 0xa6,0xd7,0xdc,0xeb,0x05,0x46,0x2e,0xb8,0x18,0xb4,0x57,0x1d,0x86,0x49,0xdb,
3261 0x69,0x4a,0x2c,0x21,0xf5,0x5e,0x0f,0x54,0x2d,0x5a,0x43,0xa9,0x7a,0x7e,0x6a,
3262 0x8e,0x50,0x4d,0x25,0x57,0xa1,0xbf,0x1b,0x15,0x05,0x43,0x7b,0x2c,0x05,0x8d,
3263 0xbd,0x3d,0x03,0x8c,0x93,0x22,0x7d,0x63,0xea,0x0a,0x57,0x05,0x06,0x0a,0xdb,
3264 0x61,0x98,0x65,0x2d,0x47,0x49,0xa8,0xe7,0xe6,0x56,0x75,0x5c,0xb8,0x64,0x08,
3265 0x63,0xa9,0x30,0x40,0x66,0xb2,0xf9,0xb6,0xe3,0x34,0xe8,0x67,0x30,0xe1,0x43,
3266 0x0b,0x87,0xff,0xc9,0xbe,0x72,0x10,0x5e,0x23,0xf0,0x9b,0xa7,0x48,0x65,0xbf,
3267 0x09,0x88,0x7b,0xcd,0x72,0xbc,0x2e,0x79,0x9b,0x7b,0x02,0x03,0x01,0x00,0x01 };
3268 static BYTE msPubKey2[] = {
3269 0x30,0x82,0x01,0x0a,0x02,0x82,0x01,0x01,0x00,0xa9,0x02,0xbd,0xc1,0x70,0xe6,
3270 0x3b,0xf2,0x4e,0x1b,0x28,0x9f,0x97,0x78,0x5e,0x30,0xea,0xa2,0xa9,0x8d,0x25,
3271 0x5f,0xf8,0xfe,0x95,0x4c,0xa3,0xb7,0xfe,0x9d,0xa2,0x20,0x3e,0x7c,0x51,0xa2,
3272 0x9b,0xa2,0x8f,0x60,0x32,0x6b,0xd1,0x42,0x64,0x79,0xee,0xac,0x76,0xc9,0x54,
3273 0xda,0xf2,0xeb,0x9c,0x86,0x1c,0x8f,0x9f,0x84,0x66,0xb3,0xc5,0x6b,0x7a,0x62,
3274 0x23,0xd6,0x1d,0x3c,0xde,0x0f,0x01,0x92,0xe8,0x96,0xc4,0xbf,0x2d,0x66,0x9a,
3275 0x9a,0x68,0x26,0x99,0xd0,0x3a,0x2c,0xbf,0x0c,0xb5,0x58,0x26,0xc1,0x46,0xe7,
3276 0x0a,0x3e,0x38,0x96,0x2c,0xa9,0x28,0x39,0xa8,0xec,0x49,0x83,0x42,0xe3,0x84,
3277 0x0f,0xbb,0x9a,0x6c,0x55,0x61,0xac,0x82,0x7c,0xa1,0x60,0x2d,0x77,0x4c,0xe9,
3278 0x99,0xb4,0x64,0x3b,0x9a,0x50,0x1c,0x31,0x08,0x24,0x14,0x9f,0xa9,0xe7,0x91,
3279 0x2b,0x18,0xe6,0x3d,0x98,0x63,0x14,0x60,0x58,0x05,0x65,0x9f,0x1d,0x37,0x52,
3280 0x87,0xf7,0xa7,0xef,0x94,0x02,0xc6,0x1b,0xd3,0xbf,0x55,0x45,0xb3,0x89,0x80,
3281 0xbf,0x3a,0xec,0x54,0x94,0x4e,0xae,0xfd,0xa7,0x7a,0x6d,0x74,0x4e,0xaf,0x18,
3282 0xcc,0x96,0x09,0x28,0x21,0x00,0x57,0x90,0x60,0x69,0x37,0xbb,0x4b,0x12,0x07,
3283 0x3c,0x56,0xff,0x5b,0xfb,0xa4,0x66,0x0a,0x08,0xa6,0xd2,0x81,0x56,0x57,0xef,
3284 0xb6,0x3b,0x5e,0x16,0x81,0x77,0x04,0xda,0xf6,0xbe,0xae,0x80,0x95,0xfe,0xb0,
3285 0xcd,0x7f,0xd6,0xa7,0x1a,0x72,0x5c,0x3c,0xca,0xbc,0xf0,0x08,0xa3,0x22,0x30,
3286 0xb3,0x06,0x85,0xc9,0xb3,0x20,0x77,0x13,0x85,0xdf,0x02,0x03,0x01,0x00,0x01 };
3287 static BYTE msPubKey3[] = {
3288 0x30,0x82,0x02,0x0a,0x02,0x82,0x02,0x01,0x00,0xf3,0x5d,0xfa,0x80,0x67,0xd4,
3289 0x5a,0xa7,0xa9,0x0c,0x2c,0x90,0x20,0xd0,0x35,0x08,0x3c,0x75,0x84,0xcd,0xb7,
3290 0x07,0x89,0x9c,0x89,0xda,0xde,0xce,0xc3,0x60,0xfa,0x91,0x68,0x5a,0x9e,0x94,
3291 0x71,0x29,0x18,0x76,0x7c,0xc2,0xe0,0xc8,0x25,0x76,0x94,0x0e,0x58,0xfa,0x04,
3292 0x34,0x36,0xe6,0xdf,0xaf,0xf7,0x80,0xba,0xe9,0x58,0x0b,0x2b,0x93,0xe5,0x9d,
3293 0x05,0xe3,0x77,0x22,0x91,0xf7,0x34,0x64,0x3c,0x22,0x91,0x1d,0x5e,0xe1,0x09,
3294 0x90,0xbc,0x14,0xfe,0xfc,0x75,0x58,0x19,0xe1,0x79,0xb7,0x07,0x92,0xa3,0xae,
3295 0x88,0x59,0x08,0xd8,0x9f,0x07,0xca,0x03,0x58,0xfc,0x68,0x29,0x6d,0x32,0xd7,
3296 0xd2,0xa8,0xcb,0x4b,0xfc,0xe1,0x0b,0x48,0x32,0x4f,0xe6,0xeb,0xb8,0xad,0x4f,
3297 0xe4,0x5c,0x6f,0x13,0x94,0x99,0xdb,0x95,0xd5,0x75,0xdb,0xa8,0x1a,0xb7,0x94,
3298 0x91,0xb4,0x77,0x5b,0xf5,0x48,0x0c,0x8f,0x6a,0x79,0x7d,0x14,0x70,0x04,0x7d,
3299 0x6d,0xaf,0x90,0xf5,0xda,0x70,0xd8,0x47,0xb7,0xbf,0x9b,0x2f,0x6c,0xe7,0x05,
3300 0xb7,0xe1,0x11,0x60,0xac,0x79,0x91,0x14,0x7c,0xc5,0xd6,0xa6,0xe4,0xe1,0x7e,
3301 0xd5,0xc3,0x7e,0xe5,0x92,0xd2,0x3c,0x00,0xb5,0x36,0x82,0xde,0x79,0xe1,0x6d,
3302 0xf3,0xb5,0x6e,0xf8,0x9f,0x33,0xc9,0xcb,0x52,0x7d,0x73,0x98,0x36,0xdb,0x8b,
3303 0xa1,0x6b,0xa2,0x95,0x97,0x9b,0xa3,0xde,0xc2,0x4d,0x26,0xff,0x06,0x96,0x67,
3304 0x25,0x06,0xc8,0xe7,0xac,0xe4,0xee,0x12,0x33,0x95,0x31,0x99,0xc8,0x35,0x08,
3305 0x4e,0x34,0xca,0x79,0x53,0xd5,0xb5,0xbe,0x63,0x32,0x59,0x40,0x36,0xc0,0xa5,
3306 0x4e,0x04,0x4d,0x3d,0xdb,0x5b,0x07,0x33,0xe4,0x58,0xbf,0xef,0x3f,0x53,0x64,
3307 0xd8,0x42,0x59,0x35,0x57,0xfd,0x0f,0x45,0x7c,0x24,0x04,0x4d,0x9e,0xd6,0x38,
3308 0x74,0x11,0x97,0x22,0x90,0xce,0x68,0x44,0x74,0x92,0x6f,0xd5,0x4b,0x6f,0xb0,
3309 0x86,0xe3,0xc7,0x36,0x42,0xa0,0xd0,0xfc,0xc1,0xc0,0x5a,0xf9,0xa3,0x61,0xb9,
3310 0x30,0x47,0x71,0x96,0x0a,0x16,0xb0,0x91,0xc0,0x42,0x95,0xef,0x10,0x7f,0x28,
3311 0x6a,0xe3,0x2a,0x1f,0xb1,0xe4,0xcd,0x03,0x3f,0x77,0x71,0x04,0xc7,0x20,0xfc,
3312 0x49,0x0f,0x1d,0x45,0x88,0xa4,0xd7,0xcb,0x7e,0x88,0xad,0x8e,0x2d,0xec,0x45,
3313 0xdb,0xc4,0x51,0x04,0xc9,0x2a,0xfc,0xec,0x86,0x9e,0x9a,0x11,0x97,0x5b,0xde,
3314 0xce,0x53,0x88,0xe6,0xe2,0xb7,0xfd,0xac,0x95,0xc2,0x28,0x40,0xdb,0xef,0x04,
3315 0x90,0xdf,0x81,0x33,0x39,0xd9,0xb2,0x45,0xa5,0x23,0x87,0x06,0xa5,0x55,0x89,
3316 0x31,0xbb,0x06,0x2d,0x60,0x0e,0x41,0x18,0x7d,0x1f,0x2e,0xb5,0x97,0xcb,0x11,
3317 0xeb,0x15,0xd5,0x24,0xa5,0x94,0xef,0x15,0x14,0x89,0xfd,0x4b,0x73,0xfa,0x32,
3318 0x5b,0xfc,0xd1,0x33,0x00,0xf9,0x59,0x62,0x70,0x07,0x32,0xea,0x2e,0xab,0x40,
3319 0x2d,0x7b,0xca,0xdd,0x21,0x67,0x1b,0x30,0x99,0x8f,0x16,0xaa,0x23,0xa8,0x41,
3320 0xd1,0xb0,0x6e,0x11,0x9b,0x36,0xc4,0xde,0x40,0x74,0x9c,0xe1,0x58,0x65,0xc1,
3321 0x60,0x1e,0x7a,0x5b,0x38,0xc8,0x8f,0xbb,0x04,0x26,0x7c,0xd4,0x16,0x40,0xe5,
3322 0xb6,0x6b,0x6c,0xaa,0x86,0xfd,0x00,0xbf,0xce,0xc1,0x35,0x02,0x03,0x01,0x00,
3323 0x01 };
3324
3325 static BOOL WINAPI verify_ms_root_policy(LPCSTR szPolicyOID,
3326  PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
3327  PCERT_CHAIN_POLICY_STATUS pPolicyStatus)
3328 {
3329     BOOL ret = verify_base_policy(szPolicyOID, pChainContext, pPolicyPara,
3330      pPolicyStatus);
3331
3332     if (ret && !pPolicyStatus->dwError)
3333     {
3334         CERT_PUBLIC_KEY_INFO msPubKey = { { 0 } };
3335         BOOL isMSRoot = FALSE;
3336         DWORD i;
3337         CRYPT_DATA_BLOB keyBlobs[] = {
3338          { sizeof(msPubKey1), msPubKey1 },
3339          { sizeof(msPubKey2), msPubKey2 },
3340          { sizeof(msPubKey3), msPubKey3 },
3341         };
3342         PCERT_SIMPLE_CHAIN rootChain =
3343          pChainContext->rgpChain[pChainContext->cChain -1 ];
3344         PCCERT_CONTEXT root =
3345          rootChain->rgpElement[rootChain->cElement - 1]->pCertContext;
3346
3347         for (i = 0; !isMSRoot && i < sizeof(keyBlobs) / sizeof(keyBlobs[0]);
3348          i++)
3349         {
3350             msPubKey.PublicKey.cbData = keyBlobs[i].cbData;
3351             msPubKey.PublicKey.pbData = keyBlobs[i].pbData;
3352             if (CertComparePublicKeyInfo(
3353              X509_ASN_ENCODING | PKCS_7_ASN_ENCODING,
3354              &root->pCertInfo->SubjectPublicKeyInfo, &msPubKey))
3355                 isMSRoot = TRUE;
3356         }
3357         if (isMSRoot)
3358             pPolicyStatus->lChainIndex = pPolicyStatus->lElementIndex = 0;
3359     }
3360     return ret;
3361 }
3362
3363 typedef BOOL (WINAPI *CertVerifyCertificateChainPolicyFunc)(LPCSTR szPolicyOID,
3364  PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
3365  PCERT_CHAIN_POLICY_STATUS pPolicyStatus);
3366
3367 BOOL WINAPI CertVerifyCertificateChainPolicy(LPCSTR szPolicyOID,
3368  PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
3369  PCERT_CHAIN_POLICY_STATUS pPolicyStatus)
3370 {
3371     static HCRYPTOIDFUNCSET set = NULL;
3372     BOOL ret = FALSE;
3373     CertVerifyCertificateChainPolicyFunc verifyPolicy = NULL;
3374     HCRYPTOIDFUNCADDR hFunc = NULL;
3375
3376     TRACE("(%s, %p, %p, %p)\n", debugstr_a(szPolicyOID), pChainContext,
3377      pPolicyPara, pPolicyStatus);
3378
3379     if (!HIWORD(szPolicyOID))
3380     {
3381         switch (LOWORD(szPolicyOID))
3382         {
3383         case LOWORD(CERT_CHAIN_POLICY_BASE):
3384             verifyPolicy = verify_base_policy;
3385             break;
3386         case LOWORD(CERT_CHAIN_POLICY_AUTHENTICODE):
3387             verifyPolicy = verify_authenticode_policy;
3388             break;
3389         case LOWORD(CERT_CHAIN_POLICY_SSL):
3390             verifyPolicy = verify_ssl_policy;
3391             break;
3392         case LOWORD(CERT_CHAIN_POLICY_BASIC_CONSTRAINTS):
3393             verifyPolicy = verify_basic_constraints_policy;
3394             break;
3395         case LOWORD(CERT_CHAIN_POLICY_MICROSOFT_ROOT):
3396             verifyPolicy = verify_ms_root_policy;
3397             break;
3398         default:
3399             FIXME("unimplemented for %d\n", LOWORD(szPolicyOID));
3400         }
3401     }
3402     if (!verifyPolicy)
3403     {
3404         if (!set)
3405             set = CryptInitOIDFunctionSet(
3406              CRYPT_OID_VERIFY_CERTIFICATE_CHAIN_POLICY_FUNC, 0);
3407         CryptGetOIDFunctionAddress(set, X509_ASN_ENCODING, szPolicyOID, 0,
3408          (void **)&verifyPolicy, &hFunc);
3409     }
3410     if (verifyPolicy)
3411         ret = verifyPolicy(szPolicyOID, pChainContext, pPolicyPara,
3412          pPolicyStatus);
3413     if (hFunc)
3414         CryptFreeOIDFunctionAddress(hFunc, 0);
3415     TRACE("returning %d (%08x)\n", ret, pPolicyStatus->dwError);
3416     return ret;
3417 }