/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #include "NSSCertDBTrustDomain.h" #include #include "ExtendedValidation.h" #include "NSSErrorsService.h" #include "OCSPRequestor.h" #include "OCSPVerificationTrustDomain.h" #include "cert.h" #include "certdb.h" #include "mozilla/Assertions.h" #include "mozilla/Casting.h" #include "mozilla/PodOperations.h" #include "mozilla/UniquePtr.h" #include "mozilla/Unused.h" #include "nsNSSCertificate.h" #include "nsServiceManagerUtils.h" #include "nsThreadUtils.h" #include "nss.h" #include "pk11pub.h" #include "pkix/Result.h" #include "pkix/pkix.h" #include "pkix/pkixnss.h" #include "prerror.h" #include "prmem.h" #include "prprf.h" #include "secerr.h" #include "CNNICHashWhitelist.inc" #include "StartComAndWoSignData.inc" using namespace mozilla; using namespace mozilla::pkix; extern LazyLogModule gCertVerifierLog; static const uint64_t ServerFailureDelaySeconds = 5 * 60; namespace mozilla { namespace psm { const char BUILTIN_ROOTS_MODULE_DEFAULT_NAME[] = "Builtin Roots Module"; NSSCertDBTrustDomain::NSSCertDBTrustDomain(SECTrustType certDBTrustType, OCSPFetching ocspFetching, OCSPCache& ocspCache, /*optional but shouldn't be*/ void* pinArg, CertVerifier::OcspGetConfig ocspGETConfig, uint32_t certShortLifetimeInDays, unsigned int minRSABits, ValidityCheckingMode validityCheckingMode, CertVerifier::SHA1Mode sha1Mode, NetscapeStepUpPolicy netscapeStepUpPolicy, const NeckoOriginAttributes& originAttributes, UniqueCERTCertList& builtChain) : mCertDBTrustType(certDBTrustType) , mOCSPFetching(ocspFetching) , mOCSPCache(ocspCache) , mPinArg(pinArg) , mOCSPGetConfig(ocspGETConfig) , mCertShortLifetimeInDays(certShortLifetimeInDays) , mMinRSABits(minRSABits) , mValidityCheckingMode(validityCheckingMode) , mSHA1Mode(sha1Mode) , mNetscapeStepUpPolicy(netscapeStepUpPolicy) , mOriginAttributes(originAttributes) , mBuiltChain(builtChain) , mCertBlocklist(do_GetService(NS_CERTBLOCKLIST_CONTRACTID)) , mOCSPStaplingStatus(CertVerifier::OCSP_STAPLING_NEVER_CHECKED) , mSCTListFromCertificate() , mSCTListFromOCSPStapling() { } // If useRoots is true, we only use root certificates in the candidate list. // If useRoots is false, we only use non-root certificates in the list. static Result FindIssuerInner(const UniqueCERTCertList& candidates, bool useRoots, Input encodedIssuerName, TrustDomain::IssuerChecker& checker, /*out*/ bool& keepGoing) { keepGoing = true; for (CERTCertListNode* n = CERT_LIST_HEAD(candidates); !CERT_LIST_END(n, candidates); n = CERT_LIST_NEXT(n)) { bool candidateIsRoot = !!n->cert->isRoot; if (candidateIsRoot != useRoots) { continue; } Input certDER; Result rv = certDER.Init(n->cert->derCert.data, n->cert->derCert.len); if (rv != Success) { continue; // probably too big } const SECItem encodedIssuerNameItem = { siBuffer, const_cast(encodedIssuerName.UnsafeGetData()), encodedIssuerName.GetLength() }; ScopedAutoSECItem nameConstraints; SECStatus srv = CERT_GetImposedNameConstraints(&encodedIssuerNameItem, &nameConstraints); if (srv != SECSuccess) { if (PR_GetError() != SEC_ERROR_EXTENSION_NOT_FOUND) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } // If no imposed name constraints were found, continue without them rv = checker.Check(certDER, nullptr, keepGoing); } else { // Otherwise apply the constraints Input nameConstraintsInput; if (nameConstraintsInput.Init(nameConstraints.data, nameConstraints.len) != Success) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } rv = checker.Check(certDER, &nameConstraintsInput, keepGoing); } if (rv != Success) { return rv; } if (!keepGoing) { break; } } return Success; } Result NSSCertDBTrustDomain::FindIssuer(Input encodedIssuerName, IssuerChecker& checker, Time) { // TODO: NSS seems to be ambiguous between "no potential issuers found" and // "there was an error trying to retrieve the potential issuers." SECItem encodedIssuerNameItem = UnsafeMapInputToSECItem(encodedIssuerName); UniqueCERTCertList candidates(CERT_CreateSubjectCertList(nullptr, CERT_GetDefaultCertDB(), &encodedIssuerNameItem, 0, false)); if (candidates) { // First, try all the root certs; then try all the non-root certs. bool keepGoing; Result rv = FindIssuerInner(candidates, true, encodedIssuerName, checker, keepGoing); if (rv != Success) { return rv; } if (keepGoing) { rv = FindIssuerInner(candidates, false, encodedIssuerName, checker, keepGoing); if (rv != Success) { return rv; } } } return Success; } Result NSSCertDBTrustDomain::GetCertTrust(EndEntityOrCA endEntityOrCA, const CertPolicyId& policy, Input candidateCertDER, /*out*/ TrustLevel& trustLevel) { // XXX: This would be cleaner and more efficient if we could get the trust // information without constructing a CERTCertificate here, but NSS doesn't // expose it in any other easy-to-use fashion. The use of // CERT_NewTempCertificate to get a CERTCertificate shouldn't be a // performance problem because NSS will just find the existing // CERTCertificate in its in-memory cache and return it. SECItem candidateCertDERSECItem = UnsafeMapInputToSECItem(candidateCertDER); UniqueCERTCertificate candidateCert( CERT_NewTempCertificate(CERT_GetDefaultCertDB(), &candidateCertDERSECItem, nullptr, false, true)); if (!candidateCert) { return MapPRErrorCodeToResult(PR_GetError()); } // Check the certificate against the OneCRL cert blocklist if (!mCertBlocklist) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } // The certificate blocklist currently only applies to TLS server // certificates. if (mCertDBTrustType == trustSSL) { bool isCertRevoked; nsresult nsrv = mCertBlocklist->IsCertRevoked( candidateCert->derIssuer.data, candidateCert->derIssuer.len, candidateCert->serialNumber.data, candidateCert->serialNumber.len, candidateCert->derSubject.data, candidateCert->derSubject.len, candidateCert->derPublicKey.data, candidateCert->derPublicKey.len, &isCertRevoked); if (NS_FAILED(nsrv)) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } if (isCertRevoked) { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: certificate is in blocklist")); return Result::ERROR_REVOKED_CERTIFICATE; } } // XXX: CERT_GetCertTrust seems to be abusing SECStatus as a boolean, where // SECSuccess means that there is a trust record and SECFailure means there // is not a trust record. I looked at NSS's internal uses of // CERT_GetCertTrust, and all that code uses the result as a boolean meaning // "We have a trust record." CERTCertTrust trust; if (CERT_GetCertTrust(candidateCert.get(), &trust) == SECSuccess) { uint32_t flags = SEC_GET_TRUST_FLAGS(&trust, mCertDBTrustType); // For DISTRUST, we use the CERTDB_TRUSTED or CERTDB_TRUSTED_CA bit, // because we can have active distrust for either type of cert. Note that // CERTDB_TERMINAL_RECORD means "stop trying to inherit trust" so if the // relevant trust bit isn't set then that means the cert must be considered // distrusted. uint32_t relevantTrustBit = endEntityOrCA == EndEntityOrCA::MustBeCA ? CERTDB_TRUSTED_CA : CERTDB_TRUSTED; if (((flags & (relevantTrustBit|CERTDB_TERMINAL_RECORD))) == CERTDB_TERMINAL_RECORD) { trustLevel = TrustLevel::ActivelyDistrusted; return Success; } // For TRUST, we only use the CERTDB_TRUSTED_CA bit, because Goanna hasn't // needed to consider end-entity certs to be their own trust anchors since // Goanna implemented nsICertOverrideService. // Of course, for this to work as expected, we need to make sure we're // inquiring about the trust of a CA and not an end-entity. If an end-entity // has the CERTDB_TRUSTED_CA bit set, Gecko does not consider it to be a // trust anchor; it must inherit its trust. if (flags & CERTDB_TRUSTED_CA && endEntityOrCA == EndEntityOrCA::MustBeCA) { if (policy.IsAnyPolicy()) { trustLevel = TrustLevel::TrustAnchor; return Success; } if (CertIsAuthoritativeForEVPolicy(candidateCert, policy)) { trustLevel = TrustLevel::TrustAnchor; return Success; } } } trustLevel = TrustLevel::InheritsTrust; return Success; } Result NSSCertDBTrustDomain::DigestBuf(Input item, DigestAlgorithm digestAlg, /*out*/ uint8_t* digestBuf, size_t digestBufLen) { return DigestBufNSS(item, digestAlg, digestBuf, digestBufLen); } static PRIntervalTime OCSPFetchingTypeToTimeoutTime(NSSCertDBTrustDomain::OCSPFetching ocspFetching) { switch (ocspFetching) { case NSSCertDBTrustDomain::FetchOCSPForDVSoftFail: return PR_SecondsToInterval(2); case NSSCertDBTrustDomain::FetchOCSPForEV: case NSSCertDBTrustDomain::FetchOCSPForDVHardFail: return PR_SecondsToInterval(10); // The rest of these are error cases. Assert in debug builds, but return // the default value corresponding to 2 seconds in release builds. case NSSCertDBTrustDomain::NeverFetchOCSP: case NSSCertDBTrustDomain::LocalOnlyOCSPForEV: PR_NOT_REACHED("we should never see this OCSPFetching type here"); break; } PR_NOT_REACHED("we're not handling every OCSPFetching type"); return PR_SecondsToInterval(2); } // Copied and modified from CERT_GetOCSPAuthorityInfoAccessLocation and // CERT_GetGeneralNameByType. Returns a non-Result::Success result on error, // Success with url == nullptr when an OCSP URI was not found, and Success with // url != nullptr when an OCSP URI was found. The output url will be owned // by the arena. static Result GetOCSPAuthorityInfoAccessLocation(const UniquePLArenaPool& arena, Input aiaExtension, /*out*/ char const*& url) { MOZ_ASSERT(arena.get()); if (!arena.get()) { return Result::FATAL_ERROR_INVALID_ARGS; } url = nullptr; SECItem aiaExtensionSECItem = UnsafeMapInputToSECItem(aiaExtension); CERTAuthInfoAccess** aia = CERT_DecodeAuthInfoAccessExtension(arena.get(), &aiaExtensionSECItem); if (!aia) { return Result::ERROR_CERT_BAD_ACCESS_LOCATION; } for (size_t i = 0; aia[i]; ++i) { if (SECOID_FindOIDTag(&aia[i]->method) == SEC_OID_PKIX_OCSP) { // NSS chooses the **last** OCSP URL; we choose the **first** CERTGeneralName* current = aia[i]->location; if (!current) { continue; } do { if (current->type == certURI) { const SECItem& location = current->name.other; // (location.len + 1) must be small enough to fit into a uint32_t, // but we limit it to a smaller bound to reduce OOM risk. if (location.len > 1024 || memchr(location.data, 0, location.len)) { // Reject embedded nulls. (NSS doesn't do this) return Result::ERROR_CERT_BAD_ACCESS_LOCATION; } // Copy the non-null-terminated SECItem into a null-terminated string. char* nullTerminatedURL( static_cast(PORT_ArenaAlloc(arena.get(), location.len + 1))); if (!nullTerminatedURL) { return Result::FATAL_ERROR_NO_MEMORY; } memcpy(nullTerminatedURL, location.data, location.len); nullTerminatedURL[location.len] = 0; url = nullTerminatedURL; return Success; } current = CERT_GetNextGeneralName(current); } while (current != aia[i]->location); } } return Success; } Result NSSCertDBTrustDomain::CheckRevocation(EndEntityOrCA endEntityOrCA, const CertID& certID, Time time, Duration validityDuration, /*optional*/ const Input* stapledOCSPResponse, /*optional*/ const Input* aiaExtension, /*optional*/ const Input* sctExtension) { // Actively distrusted certificates will have already been blocked by // GetCertTrust. // TODO: need to verify that IsRevoked isn't called for trust anchors AND // that that fact is documented in mozillapkix. MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: Top of CheckRevocation\n")); // Bug 991815: The BR allow OCSP for intermediates to be up to one year old. // Since this affects EV there is no reason why DV should be more strict // so all intermediatates are allowed to have OCSP responses up to one year // old. uint16_t maxOCSPLifetimeInDays = 10; if (endEntityOrCA == EndEntityOrCA::MustBeCA) { maxOCSPLifetimeInDays = 365; } // If we have a stapled OCSP response then the verification of that response // determines the result unless the OCSP response is expired. We make an // exception for expired responses because some servers, nginx in particular, // are known to serve expired responses due to bugs. // We keep track of the result of verifying the stapled response but don't // immediately return failure if the response has expired. // // We only set the OCSP stapling status if we're validating the end-entity // certificate. Non-end-entity certificates would always be // OCSP_STAPLING_NONE unless/until we implement multi-stapling. Result stapledOCSPResponseResult = Success; if (stapledOCSPResponse) { PR_ASSERT(endEntityOrCA == EndEntityOrCA::MustBeEndEntity); bool expired; stapledOCSPResponseResult = VerifyAndMaybeCacheEncodedOCSPResponse(certID, time, maxOCSPLifetimeInDays, *stapledOCSPResponse, ResponseWasStapled, expired); if (stapledOCSPResponseResult == Success) { // stapled OCSP response present and good mOCSPStaplingStatus = CertVerifier::OCSP_STAPLING_GOOD; MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: stapled OCSP response: good")); return Success; } if (stapledOCSPResponseResult == Result::ERROR_OCSP_OLD_RESPONSE || expired) { // stapled OCSP response present but expired mOCSPStaplingStatus = CertVerifier::OCSP_STAPLING_EXPIRED; MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: expired stapled OCSP response")); } else { // stapled OCSP response present but invalid for some reason mOCSPStaplingStatus = CertVerifier::OCSP_STAPLING_INVALID; MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: stapled OCSP response: failure")); return stapledOCSPResponseResult; } } else if (endEntityOrCA == EndEntityOrCA::MustBeEndEntity) { // no stapled OCSP response mOCSPStaplingStatus = CertVerifier::OCSP_STAPLING_NONE; MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: no stapled OCSP response")); } Result cachedResponseResult = Success; Time cachedResponseValidThrough(Time::uninitialized); bool cachedResponsePresent = mOCSPCache.Get(certID, mOriginAttributes, cachedResponseResult, cachedResponseValidThrough); if (cachedResponsePresent) { if (cachedResponseResult == Success && cachedResponseValidThrough >= time) { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: cached OCSP response: good")); return Success; } // If we have a cached revoked response, use it. if (cachedResponseResult == Result::ERROR_REVOKED_CERTIFICATE) { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: cached OCSP response: revoked")); return Result::ERROR_REVOKED_CERTIFICATE; } // The cached response may indicate an unknown certificate or it may be // expired. Don't return with either of these statuses yet - we may be // able to fetch a more recent one. MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: cached OCSP response: error %d", cachedResponseResult)); // When a good cached response has expired, it is more convenient // to convert that to an error code and just deal with // cachedResponseResult from here on out. if (cachedResponseResult == Success && cachedResponseValidThrough < time) { cachedResponseResult = Result::ERROR_OCSP_OLD_RESPONSE; } // We may have a cached indication of server failure. Ignore it if // it has expired. if (cachedResponseResult != Success && cachedResponseResult != Result::ERROR_OCSP_UNKNOWN_CERT && cachedResponseResult != Result::ERROR_OCSP_OLD_RESPONSE && cachedResponseValidThrough < time) { cachedResponseResult = Success; cachedResponsePresent = false; } } else { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: no cached OCSP response")); } // At this point, if and only if cachedErrorResult is Success, there was no // cached response. PR_ASSERT((!cachedResponsePresent && cachedResponseResult == Success) || (cachedResponsePresent && cachedResponseResult != Success)); // If we have a fresh OneCRL Blocklist we can skip OCSP for CA certs bool blocklistIsFresh; nsresult nsrv = mCertBlocklist->IsBlocklistFresh(&blocklistIsFresh); if (NS_FAILED(nsrv)) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } // TODO: We still need to handle the fallback for expired responses. But, // if/when we disable OCSP fetching by default, it would be ambiguous whether // security.OCSP.enable==0 means "I want the default" or "I really never want // you to ever fetch OCSP." Duration shortLifetime(mCertShortLifetimeInDays * Time::ONE_DAY_IN_SECONDS); if ((mOCSPFetching == NeverFetchOCSP) || (validityDuration < shortLifetime) || (endEntityOrCA == EndEntityOrCA::MustBeCA && (mOCSPFetching == FetchOCSPForDVHardFail || mOCSPFetching == FetchOCSPForDVSoftFail || blocklistIsFresh))) { // We're not going to be doing any fetching, so if there was a cached // "unknown" response, say so. if (cachedResponseResult == Result::ERROR_OCSP_UNKNOWN_CERT) { return Result::ERROR_OCSP_UNKNOWN_CERT; } // If we're doing hard-fail, we want to know if we have a cached response // that has expired. if (mOCSPFetching == FetchOCSPForDVHardFail && cachedResponseResult == Result::ERROR_OCSP_OLD_RESPONSE) { return Result::ERROR_OCSP_OLD_RESPONSE; } return Success; } if (mOCSPFetching == LocalOnlyOCSPForEV) { if (cachedResponseResult != Success) { return cachedResponseResult; } return Result::ERROR_OCSP_UNKNOWN_CERT; } UniquePLArenaPool arena(PORT_NewArena(DER_DEFAULT_CHUNKSIZE)); if (!arena) { return Result::FATAL_ERROR_NO_MEMORY; } Result rv; const char* url = nullptr; // owned by the arena if (aiaExtension) { rv = GetOCSPAuthorityInfoAccessLocation(arena, *aiaExtension, url); if (rv != Success) { return rv; } } if (!url) { if (mOCSPFetching == FetchOCSPForEV || cachedResponseResult == Result::ERROR_OCSP_UNKNOWN_CERT) { return Result::ERROR_OCSP_UNKNOWN_CERT; } if (cachedResponseResult == Result::ERROR_OCSP_OLD_RESPONSE) { return Result::ERROR_OCSP_OLD_RESPONSE; } if (stapledOCSPResponseResult != Success) { return stapledOCSPResponseResult; } // Nothing to do if we don't have an OCSP responder URI for the cert; just // assume it is good. Note that this is the confusing, but intended, // interpretation of "strict" revocation checking in the face of a // certificate that lacks an OCSP responder URI. return Success; } // Only request a response if we didn't have a cached indication of failure // (don't keep requesting responses from a failing server). Input response; bool attemptedRequest; if (cachedResponseResult == Success || cachedResponseResult == Result::ERROR_OCSP_UNKNOWN_CERT || cachedResponseResult == Result::ERROR_OCSP_OLD_RESPONSE) { uint8_t ocspRequest[OCSP_REQUEST_MAX_LENGTH]; size_t ocspRequestLength; rv = CreateEncodedOCSPRequest(*this, certID, ocspRequest, ocspRequestLength); if (rv != Success) { return rv; } SECItem ocspRequestItem = { siBuffer, ocspRequest, static_cast(ocspRequestLength) }; // Owned by arena SECItem* responseSECItem = nullptr; Result tempRV = DoOCSPRequest(arena, url, mOriginAttributes, &ocspRequestItem, OCSPFetchingTypeToTimeoutTime(mOCSPFetching), mOCSPGetConfig == CertVerifier::ocspGetEnabled, responseSECItem); MOZ_ASSERT((tempRV != Success) || responseSECItem); if (tempRV != Success) { rv = tempRV; } else if (response.Init(responseSECItem->data, responseSECItem->len) != Success) { rv = Result::ERROR_OCSP_MALFORMED_RESPONSE; // too big } attemptedRequest = true; } else { rv = cachedResponseResult; attemptedRequest = false; } if (response.GetLength() == 0) { Result error = rv; if (attemptedRequest) { Time timeout(time); if (timeout.AddSeconds(ServerFailureDelaySeconds) != Success) { return Result::FATAL_ERROR_LIBRARY_FAILURE; // integer overflow } rv = mOCSPCache.Put(certID, mOriginAttributes, error, time, timeout); if (rv != Success) { return rv; } } if (mOCSPFetching != FetchOCSPForDVSoftFail) { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: returning SECFailure after " "OCSP request failure")); return error; } if (cachedResponseResult == Result::ERROR_OCSP_UNKNOWN_CERT) { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: returning SECFailure from cached " "response after OCSP request failure")); return cachedResponseResult; } if (stapledOCSPResponseResult != Success) { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: returning SECFailure from expired " "stapled response after OCSP request failure")); return stapledOCSPResponseResult; } MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: returning SECSuccess after " "OCSP request failure")); return Success; // Soft fail -> success :( } // If the response from the network has expired but indicates a revoked // or unknown certificate, PR_GetError() will return the appropriate error. // We actually ignore expired here. bool expired; rv = VerifyAndMaybeCacheEncodedOCSPResponse(certID, time, maxOCSPLifetimeInDays, response, ResponseIsFromNetwork, expired); if (rv == Success || mOCSPFetching != FetchOCSPForDVSoftFail) { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: returning after VerifyEncodedOCSPResponse")); return rv; } if (rv == Result::ERROR_OCSP_UNKNOWN_CERT || rv == Result::ERROR_REVOKED_CERTIFICATE) { return rv; } if (stapledOCSPResponseResult != Success) { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: returning SECFailure from expired stapled " "response after OCSP request verification failure")); return stapledOCSPResponseResult; } MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: end of CheckRevocation")); return Success; // Soft fail -> success :( } Result NSSCertDBTrustDomain::VerifyAndMaybeCacheEncodedOCSPResponse( const CertID& certID, Time time, uint16_t maxLifetimeInDays, Input encodedResponse, EncodedResponseSource responseSource, /*out*/ bool& expired) { Time thisUpdate(Time::uninitialized); Time validThrough(Time::uninitialized); // We use a try and fallback approach which first mandates good signature // digest algorithms, then falls back to SHA-1 if this fails. If a delegated // OCSP response signing certificate was issued with a SHA-1 signature, // verification initially fails. We cache the failure and then re-use that // result even when doing fallback (i.e. when weak signature digest algorithms // should succeed). To address this we use an OCSPVerificationTrustDomain // here, rather than using *this, to ensure verification succeeds for all // allowed signature digest algorithms. OCSPVerificationTrustDomain trustDomain(*this); Result rv = VerifyEncodedOCSPResponse(trustDomain, certID, time, maxLifetimeInDays, encodedResponse, expired, &thisUpdate, &validThrough); // If a response was stapled and expired, we don't want to cache it. Return // early to simplify the logic here. if (responseSource == ResponseWasStapled && expired) { PR_ASSERT(rv != Success); return rv; } // validThrough is only trustworthy if the response successfully verifies // or it indicates a revoked or unknown certificate. // If this isn't the case, store an indication of failure (to prevent // repeatedly requesting a response from a failing server). if (rv != Success && rv != Result::ERROR_REVOKED_CERTIFICATE && rv != Result::ERROR_OCSP_UNKNOWN_CERT) { validThrough = time; if (validThrough.AddSeconds(ServerFailureDelaySeconds) != Success) { return Result::FATAL_ERROR_LIBRARY_FAILURE; // integer overflow } } if (responseSource == ResponseIsFromNetwork || rv == Success || rv == Result::ERROR_REVOKED_CERTIFICATE || rv == Result::ERROR_OCSP_UNKNOWN_CERT) { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: caching OCSP response")); Result putRV = mOCSPCache.Put(certID, mOriginAttributes, rv, thisUpdate, validThrough); if (putRV != Success) { return putRV; } } return rv; } static const uint8_t CNNIC_ROOT_CA_SUBJECT_DATA[] = "\x30\x32\x31\x0B\x30\x09\x06\x03\x55\x04\x06\x13\x02\x43\x4E\x31\x0E\x30" "\x0C\x06\x03\x55\x04\x0A\x13\x05\x43\x4E\x4E\x49\x43\x31\x13\x30\x11\x06" "\x03\x55\x04\x03\x13\x0A\x43\x4E\x4E\x49\x43\x20\x52\x4F\x4F\x54"; static const uint8_t CNNIC_EV_ROOT_CA_SUBJECT_DATA[] = "\x30\x81\x8A\x31\x0B\x30\x09\x06\x03\x55\x04\x06\x13\x02\x43\x4E\x31\x32" "\x30\x30\x06\x03\x55\x04\x0A\x0C\x29\x43\x68\x69\x6E\x61\x20\x49\x6E\x74" "\x65\x72\x6E\x65\x74\x20\x4E\x65\x74\x77\x6F\x72\x6B\x20\x49\x6E\x66\x6F" "\x72\x6D\x61\x74\x69\x6F\x6E\x20\x43\x65\x6E\x74\x65\x72\x31\x47\x30\x45" "\x06\x03\x55\x04\x03\x0C\x3E\x43\x68\x69\x6E\x61\x20\x49\x6E\x74\x65\x72" "\x6E\x65\x74\x20\x4E\x65\x74\x77\x6F\x72\x6B\x20\x49\x6E\x66\x6F\x72\x6D" "\x61\x74\x69\x6F\x6E\x20\x43\x65\x6E\x74\x65\x72\x20\x45\x56\x20\x43\x65" "\x72\x74\x69\x66\x69\x63\x61\x74\x65\x73\x20\x52\x6F\x6F\x74"; class WhitelistedCNNICHashBinarySearchComparator { public: explicit WhitelistedCNNICHashBinarySearchComparator(const uint8_t* aTarget, size_t aTargetLength) : mTarget(aTarget) { MOZ_ASSERT(aTargetLength == CNNIC_WHITELIST_HASH_LEN, "Hashes should be of the same length."); } int operator()(const WhitelistedCNNICHash val) const { return memcmp(mTarget, val.hash, CNNIC_WHITELIST_HASH_LEN); } private: const uint8_t* mTarget; }; static bool CertIsStartComOrWoSign(const CERTCertificate* cert) { for (const DataAndLength& dn : StartComAndWoSignDNs) { if (cert->derSubject.len == dn.len && PodEqual(cert->derSubject.data, dn.data, dn.len)) { return true; } } return false; } // If a certificate in the given chain appears to have been issued by one of // seven roots operated by StartCom and WoSign that are not trusted to issue new // certificates, verify that the end-entity has a notBefore date before 21 // October 2016. If the value of notBefore is after this time, the chain is not // valid. // (NB: While there are seven distinct roots being checked for, two of them // share distinguished names, resulting in six distinct distinguished names to // actually look for.) static Result CheckForStartComOrWoSign(const UniqueCERTCertList& certChain) { if (CERT_LIST_EMPTY(certChain)) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } const CERTCertListNode* endEntityNode = CERT_LIST_HEAD(certChain); if (!endEntityNode || !endEntityNode->cert) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } PRTime notBefore; PRTime notAfter; if (CERT_GetCertTimes(endEntityNode->cert, ¬Before, ¬After) != SECSuccess) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } // PRTime is microseconds since the epoch, whereas JS time is milliseconds. // (new Date("2016-10-21T00:00:00Z")).getTime() * 1000 static const PRTime OCTOBER_21_2016 = 1477008000000000; if (notBefore <= OCTOBER_21_2016) { return Success; } for (const CERTCertListNode* node = CERT_LIST_HEAD(certChain); !CERT_LIST_END(node, certChain); node = CERT_LIST_NEXT(node)) { if (!node || !node->cert) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } if (CertIsStartComOrWoSign(node->cert)) { return Result::ERROR_REVOKED_CERTIFICATE; } } return Success; } Result NSSCertDBTrustDomain::IsChainValid(const DERArray& certArray, Time time, const CertPolicyId& requiredPolicy) { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: IsChainValid")); UniqueCERTCertList certList; SECStatus srv = ConstructCERTCertListFromReversedDERArray(certArray, certList); if (srv != SECSuccess) { return MapPRErrorCodeToResult(PR_GetError()); } if (CERT_LIST_EMPTY(certList)) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } Result rv = CheckForStartComOrWoSign(certList); if (rv != Success) { return rv; } // If the certificate appears to have been issued by a CNNIC root, only allow // it if it is on the whitelist. CERTCertListNode* rootNode = CERT_LIST_TAIL(certList); if (!rootNode) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } CERTCertificate* root = rootNode->cert; if (!root) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } if ((root->derSubject.len == sizeof(CNNIC_ROOT_CA_SUBJECT_DATA) - 1 && memcmp(root->derSubject.data, CNNIC_ROOT_CA_SUBJECT_DATA, root->derSubject.len) == 0) || (root->derSubject.len == sizeof(CNNIC_EV_ROOT_CA_SUBJECT_DATA) - 1 && memcmp(root->derSubject.data, CNNIC_EV_ROOT_CA_SUBJECT_DATA, root->derSubject.len) == 0)) { CERTCertListNode* certNode = CERT_LIST_HEAD(certList); if (!certNode) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } CERTCertificate* cert = certNode->cert; if (!cert) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } Digest digest; nsresult nsrv = digest.DigestBuf(SEC_OID_SHA256, cert->derCert.data, cert->derCert.len); if (NS_FAILED(nsrv)) { return Result::FATAL_ERROR_LIBRARY_FAILURE; } const uint8_t* certHash( BitwiseCast(digest.get().data)); size_t certHashLen = digest.get().len; size_t unused; if (!mozilla::BinarySearchIf(WhitelistedCNNICHashes, 0, ArrayLength(WhitelistedCNNICHashes), WhitelistedCNNICHashBinarySearchComparator( certHash, certHashLen), &unused)) { return Result::ERROR_REVOKED_CERTIFICATE; } } bool isBuiltInRoot = false; rv = IsCertBuiltInRoot(root, isBuiltInRoot); if (rv != Success) { return rv; } mBuiltChain = Move(certList); return Success; } Result NSSCertDBTrustDomain::CheckSignatureDigestAlgorithm(DigestAlgorithm aAlg, EndEntityOrCA endEntityOrCA, Time notBefore) { // (new Date("2016-01-01T00:00:00Z")).getTime() / 1000 static const Time JANUARY_FIRST_2016 = TimeFromEpochInSeconds(1451606400); MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("NSSCertDBTrustDomain: CheckSignatureDigestAlgorithm")); if (aAlg == DigestAlgorithm::sha1) { switch (mSHA1Mode) { case CertVerifier::SHA1Mode::Forbidden: MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("SHA-1 certificate rejected")); return Result::ERROR_CERT_SIGNATURE_ALGORITHM_DISABLED; case CertVerifier::SHA1Mode::ImportedRootOrBefore2016: if (JANUARY_FIRST_2016 <= notBefore) { MOZ_LOG(gCertVerifierLog, LogLevel::Debug, ("Post-2015 SHA-1 certificate rejected")); return Result::ERROR_CERT_SIGNATURE_ALGORITHM_DISABLED; } break; case CertVerifier::SHA1Mode::Allowed: // Enforcing that the resulting chain uses an imported root is only // possible at a higher level. This is done in CertVerifier::VerifyCert. case CertVerifier::SHA1Mode::ImportedRoot: default: break; // MSVC warns unless we explicitly handle this now-unused option. case CertVerifier::SHA1Mode::UsedToBeBefore2016ButNowIsForbidden: MOZ_ASSERT_UNREACHABLE("unexpected SHA1Mode type"); return Result::FATAL_ERROR_LIBRARY_FAILURE; } } return Success; } Result NSSCertDBTrustDomain::CheckRSAPublicKeyModulusSizeInBits( EndEntityOrCA /*endEntityOrCA*/, unsigned int modulusSizeInBits) { if (modulusSizeInBits < mMinRSABits) { return Result::ERROR_INADEQUATE_KEY_SIZE; } return Success; } Result NSSCertDBTrustDomain::VerifyRSAPKCS1SignedDigest( const SignedDigest& signedDigest, Input subjectPublicKeyInfo) { return VerifyRSAPKCS1SignedDigestNSS(signedDigest, subjectPublicKeyInfo, mPinArg); } Result NSSCertDBTrustDomain::CheckECDSACurveIsAcceptable( EndEntityOrCA /*endEntityOrCA*/, NamedCurve curve) { switch (curve) { case NamedCurve::secp256r1: // fall through case NamedCurve::secp384r1: // fall through case NamedCurve::secp521r1: return Success; } return Result::ERROR_UNSUPPORTED_ELLIPTIC_CURVE; } Result NSSCertDBTrustDomain::VerifyECDSASignedDigest(const SignedDigest& signedDigest, Input subjectPublicKeyInfo) { return VerifyECDSASignedDigestNSS(signedDigest, subjectPublicKeyInfo, mPinArg); } Result NSSCertDBTrustDomain::CheckValidityIsAcceptable(Time notBefore, Time notAfter, EndEntityOrCA endEntityOrCA, KeyPurposeId keyPurpose) { if (endEntityOrCA != EndEntityOrCA::MustBeEndEntity) { return Success; } if (keyPurpose == KeyPurposeId::id_kp_OCSPSigning) { return Success; } Duration DURATION_27_MONTHS_PLUS_SLOP((2 * 365 + 3 * 31 + 7) * Time::ONE_DAY_IN_SECONDS); Duration maxValidityDuration(UINT64_MAX); Duration validityDuration(notBefore, notAfter); switch (mValidityCheckingMode) { case ValidityCheckingMode::CheckingOff: return Success; case ValidityCheckingMode::CheckForEV: // The EV Guidelines say the maximum is 27 months, but we use a slightly // higher limit here to (hopefully) minimize compatibility breakage. maxValidityDuration = DURATION_27_MONTHS_PLUS_SLOP; break; default: PR_NOT_REACHED("We're not handling every ValidityCheckingMode type"); } if (validityDuration > maxValidityDuration) { return Result::ERROR_VALIDITY_TOO_LONG; } return Success; } Result NSSCertDBTrustDomain::NetscapeStepUpMatchesServerAuth(Time notBefore, /*out*/ bool& matches) { // (new Date("2015-08-23T00:00:00Z")).getTime() / 1000 static const Time AUGUST_23_2015 = TimeFromEpochInSeconds(1440288000); // (new Date("2016-08-23T00:00:00Z")).getTime() / 1000 static const Time AUGUST_23_2016 = TimeFromEpochInSeconds(1471910400); switch (mNetscapeStepUpPolicy) { case NetscapeStepUpPolicy::AlwaysMatch: matches = true; return Success; case NetscapeStepUpPolicy::MatchBefore23August2016: matches = notBefore < AUGUST_23_2016; return Success; case NetscapeStepUpPolicy::MatchBefore23August2015: matches = notBefore < AUGUST_23_2015; return Success; case NetscapeStepUpPolicy::NeverMatch: matches = false; return Success; default: MOZ_ASSERT_UNREACHABLE("unhandled NetscapeStepUpPolicy type"); } return Result::FATAL_ERROR_LIBRARY_FAILURE; } void NSSCertDBTrustDomain::ResetAccumulatedState() { mOCSPStaplingStatus = CertVerifier::OCSP_STAPLING_NEVER_CHECKED; mSCTListFromOCSPStapling = nullptr; mSCTListFromCertificate = nullptr; } static Input SECItemToInput(const UniqueSECItem& item) { Input result; if (item) { MOZ_ASSERT(item->type == siBuffer); Result rv = result.Init(item->data, item->len); // As used here, |item| originally comes from an Input, // so there should be no issues converting it back. MOZ_ASSERT(rv == Success); Unused << rv; // suppresses warnings in release builds } return result; } Input NSSCertDBTrustDomain::GetSCTListFromCertificate() const { return SECItemToInput(mSCTListFromCertificate); } Input NSSCertDBTrustDomain::GetSCTListFromOCSPStapling() const { return SECItemToInput(mSCTListFromOCSPStapling); } void NSSCertDBTrustDomain::NoteAuxiliaryExtension(AuxiliaryExtension extension, Input extensionData) { UniqueSECItem* out = nullptr; switch (extension) { case AuxiliaryExtension::EmbeddedSCTList: out = &mSCTListFromCertificate; break; case AuxiliaryExtension::SCTListFromOCSPResponse: out = &mSCTListFromOCSPStapling; break; default: MOZ_ASSERT_UNREACHABLE("unhandled AuxiliaryExtension"); } if (out) { SECItem extensionDataItem = UnsafeMapInputToSECItem(extensionData); out->reset(SECITEM_DupItem(&extensionDataItem)); } } SECStatus InitializeNSS(const nsACString& dir, bool readOnly, bool loadPKCS11Modules) { MOZ_ASSERT(NS_IsMainThread()); // The NSS_INIT_NOROOTINIT flag turns off the loading of the root certs // module by NSS_Initialize because we will load it in InstallLoadableRoots // later. It also allows us to work around a bug in the system NSS in // Ubuntu 8.04, which loads any nonexistent "/libnssckbi.so" as // "/usr/lib/nss/libnssckbi.so". uint32_t flags = NSS_INIT_NOROOTINIT | NSS_INIT_OPTIMIZESPACE; if (readOnly) { flags |= NSS_INIT_READONLY; } if (!loadPKCS11Modules) { flags |= NSS_INIT_NOMODDB; } nsAutoCString dbTypeAndDirectory; #ifdef MOZ_SECURITY_SQLSTORE // Not strictly necessary with current NSS versions, but can't hurt to be explicit. dbTypeAndDirectory.Append("sql:"); #else dbTypeAndDirectory.Append("dbm:"); #endif dbTypeAndDirectory.Append(dir); return ::NSS_Initialize(dbTypeAndDirectory.get(), "", "", SECMOD_DB, flags); } void DisableMD5() { NSS_SetAlgorithmPolicy(SEC_OID_MD5, 0, NSS_USE_ALG_IN_CERT_SIGNATURE | NSS_USE_ALG_IN_CMS_SIGNATURE); NSS_SetAlgorithmPolicy(SEC_OID_PKCS1_MD5_WITH_RSA_ENCRYPTION, 0, NSS_USE_ALG_IN_CERT_SIGNATURE | NSS_USE_ALG_IN_CMS_SIGNATURE); NSS_SetAlgorithmPolicy(SEC_OID_PKCS5_PBE_WITH_MD5_AND_DES_CBC, 0, NSS_USE_ALG_IN_CERT_SIGNATURE | NSS_USE_ALG_IN_CMS_SIGNATURE); } SECStatus LoadLoadableRoots(/*optional*/ const char* dir, const char* modNameUTF8) { PR_ASSERT(modNameUTF8); if (!modNameUTF8) { PR_SetError(SEC_ERROR_INVALID_ARGS, 0); return SECFailure; } UniquePtr fullLibraryPath(PR_GetLibraryName(dir, "nssckbi"), PR_FreeLibraryName); if (!fullLibraryPath) { return SECFailure; } // Escape the \ and " characters. nsAutoCString escapedFullLibraryPath(fullLibraryPath.get()); escapedFullLibraryPath.ReplaceSubstring("\\", "\\\\"); escapedFullLibraryPath.ReplaceSubstring("\"", "\\\""); if (escapedFullLibraryPath.IsEmpty()) { return SECFailure; } // If a module exists with the same name, delete it. int modType; SECMOD_DeleteModule(modNameUTF8, &modType); nsAutoCString pkcs11ModuleSpec; pkcs11ModuleSpec.AppendPrintf("name=\"%s\" library=\"%s\"", modNameUTF8, escapedFullLibraryPath.get()); if (pkcs11ModuleSpec.IsEmpty()) { return SECFailure; } UniqueSECMODModule rootsModule( SECMOD_LoadUserModule(const_cast(pkcs11ModuleSpec.get()), nullptr, false)); if (!rootsModule) { return SECFailure; } if (!rootsModule->loaded) { PR_SetError(PR_INVALID_STATE_ERROR, 0); return SECFailure; } return SECSuccess; } void UnloadLoadableRoots(const char* modNameUTF8) { PR_ASSERT(modNameUTF8); UniqueSECMODModule rootsModule(SECMOD_FindModule(modNameUTF8)); if (rootsModule) { SECMOD_UnloadUserModule(rootsModule.get()); } } nsresult DefaultServerNicknameForCert(const CERTCertificate* cert, /*out*/ nsCString& nickname) { MOZ_ASSERT(cert); NS_ENSURE_ARG_POINTER(cert); UniquePORTString baseName(CERT_GetCommonName(&cert->subject)); if (!baseName) { baseName = UniquePORTString(CERT_GetOrgUnitName(&cert->subject)); } if (!baseName) { baseName = UniquePORTString(CERT_GetOrgName(&cert->subject)); } if (!baseName) { baseName = UniquePORTString(CERT_GetLocalityName(&cert->subject)); } if (!baseName) { baseName = UniquePORTString(CERT_GetStateName(&cert->subject)); } if (!baseName) { baseName = UniquePORTString(CERT_GetCountryName(&cert->subject)); } if (!baseName) { return NS_ERROR_FAILURE; } // This function is only used in contexts where a failure to find a suitable // nickname does not block the overall task from succeeding. // As such, we use an arbitrary limit to prevent this nickname searching // process from taking forever. static const uint32_t ARBITRARY_LIMIT = 500; for (uint32_t count = 1; count < ARBITRARY_LIMIT; count++) { nickname = baseName.get(); if (count != 1) { nickname.AppendPrintf(" #%u", count); } if (nickname.IsEmpty()) { return NS_ERROR_FAILURE; } bool conflict = SEC_CertNicknameConflict(nickname.get(), &cert->derSubject, cert->dbhandle); if (!conflict) { return NS_OK; } } return NS_ERROR_FAILURE; } /** * Given a list of certificates representing a verified certificate path from an * end-entity certificate to a trust anchor, imports the intermediate * certificates into the permanent certificate database. This is an attempt to * cope with misconfigured servers that don't include the appropriate * intermediate certificates in the TLS handshake. * * @param certList the verified certificate list */ void SaveIntermediateCerts(const UniqueCERTCertList& certList) { if (!certList) { return; } UniquePK11SlotInfo slot(PK11_GetInternalKeySlot()); if (!slot) { return; } bool isEndEntity = true; for (CERTCertListNode* node = CERT_LIST_HEAD(certList); !CERT_LIST_END(node, certList); node = CERT_LIST_NEXT(node)) { if (isEndEntity) { // Skip the end-entity; we only want to store intermediates isEndEntity = false; continue; } if (node->cert->slot) { // This cert was found on a token; no need to remember it in the permanent // database. continue; } if (node->cert->isperm) { // We don't need to remember certs already stored in perm db. continue; } // No need to save the trust anchor - it's either already a permanent // certificate or it's the Microsoft Family Safety root or an enterprise // root temporarily imported via the child mode or enterprise root features. // We don't want to import these because they're intended to be temporary // (and because importing them happens to reset their trust settings, which // breaks these features). if (node == CERT_LIST_TAIL(certList)) { continue; } nsAutoCString nickname; nsresult rv = DefaultServerNicknameForCert(node->cert, nickname); if (NS_FAILED(rv)) { continue; } // As mentioned in the documentation of this function, we're importing only // to cope with misconfigured servers. As such, we ignore the return value // below, since it doesn't really matter if the import fails. Unused << PK11_ImportCert(slot.get(), node->cert, CK_INVALID_HANDLE, nickname.get(), false); } } } } // namespace mozilla::psm