| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "net/cert/cert_verify_proc_nss.h" |
| |
| #include <cert.h> |
| #include <nss.h> |
| #include <prerror.h> |
| #include <secerr.h> |
| #include <sechash.h> |
| #include <sslerr.h> |
| |
| #include <memory> |
| #include <string> |
| #include <vector> |
| |
| #include "base/logging.h" |
| #include "base/macros.h" |
| #include "base/sha1.h" |
| #include "build/build_config.h" |
| #include "crypto/nss_util.h" |
| #include "crypto/scoped_nss_types.h" |
| #include "crypto/sha2.h" |
| #include "net/base/net_errors.h" |
| #include "net/cert/asn1_util.h" |
| #include "net/cert/cert_status_flags.h" |
| #include "net/cert/cert_verifier.h" |
| #include "net/cert/cert_verify_result.h" |
| #include "net/cert/crl_set.h" |
| #include "net/cert/ev_root_ca_metadata.h" |
| #include "net/cert/x509_certificate.h" |
| #include "net/cert/x509_util_nss.h" |
| |
| #include <dlfcn.h> |
| |
| namespace net { |
| |
| namespace { |
| |
| typedef std::unique_ptr< |
| CERTCertificatePolicies, |
| crypto::NSSDestroyer<CERTCertificatePolicies, |
| CERT_DestroyCertificatePoliciesExtension>> |
| ScopedCERTCertificatePolicies; |
| |
| typedef std::unique_ptr< |
| CERTCertList, |
| crypto::NSSDestroyer<CERTCertList, CERT_DestroyCertList>> |
| ScopedCERTCertList; |
| |
| // ScopedCERTValOutParam manages destruction of values in the CERTValOutParam |
| // array that cvout points to. cvout must be initialized as passed to |
| // CERT_PKIXVerifyCert, so that the array must be terminated with |
| // cert_po_end type. |
| // When it goes out of scope, it destroys values of cert_po_trustAnchor |
| // and cert_po_certList types, but doesn't release the array itself. |
| class ScopedCERTValOutParam { |
| public: |
| explicit ScopedCERTValOutParam(CERTValOutParam* cvout) : cvout_(cvout) {} |
| |
| ~ScopedCERTValOutParam() { |
| Clear(); |
| } |
| |
| // Free the internal resources, but do not release the array itself. |
| void Clear() { |
| if (cvout_ == NULL) |
| return; |
| for (CERTValOutParam *p = cvout_; p->type != cert_po_end; p++) { |
| switch (p->type) { |
| case cert_po_trustAnchor: |
| if (p->value.pointer.cert) { |
| CERT_DestroyCertificate(p->value.pointer.cert); |
| p->value.pointer.cert = NULL; |
| } |
| break; |
| case cert_po_certList: |
| if (p->value.pointer.chain) { |
| CERT_DestroyCertList(p->value.pointer.chain); |
| p->value.pointer.chain = NULL; |
| } |
| break; |
| default: |
| break; |
| } |
| } |
| } |
| |
| private: |
| CERTValOutParam* cvout_; |
| |
| DISALLOW_COPY_AND_ASSIGN(ScopedCERTValOutParam); |
| }; |
| |
| // Map PORT_GetError() return values to our network error codes. |
| int MapSecurityError(int err) { |
| switch (err) { |
| case PR_DIRECTORY_LOOKUP_ERROR: // DNS lookup error. |
| return ERR_NAME_NOT_RESOLVED; |
| case SEC_ERROR_INVALID_ARGS: |
| return ERR_INVALID_ARGUMENT; |
| case SSL_ERROR_BAD_CERT_DOMAIN: |
| return ERR_CERT_COMMON_NAME_INVALID; |
| case SEC_ERROR_INVALID_TIME: |
| case SEC_ERROR_EXPIRED_CERTIFICATE: |
| case SEC_ERROR_EXPIRED_ISSUER_CERTIFICATE: |
| return ERR_CERT_DATE_INVALID; |
| case SEC_ERROR_UNKNOWN_ISSUER: |
| case SEC_ERROR_UNTRUSTED_ISSUER: |
| case SEC_ERROR_CA_CERT_INVALID: |
| case SEC_ERROR_APPLICATION_CALLBACK_ERROR: // Rejected by |
| // chain_verify_callback. |
| return ERR_CERT_AUTHORITY_INVALID; |
| // TODO(port): map ERR_CERT_NO_REVOCATION_MECHANISM. |
| case SEC_ERROR_OCSP_BAD_HTTP_RESPONSE: |
| case SEC_ERROR_OCSP_SERVER_ERROR: |
| return ERR_CERT_UNABLE_TO_CHECK_REVOCATION; |
| case SEC_ERROR_REVOKED_CERTIFICATE: |
| case SEC_ERROR_UNTRUSTED_CERT: // Treat as revoked. |
| return ERR_CERT_REVOKED; |
| case SEC_ERROR_CERT_NOT_IN_NAME_SPACE: |
| return ERR_CERT_NAME_CONSTRAINT_VIOLATION; |
| case SEC_ERROR_BAD_DER: |
| case SEC_ERROR_BAD_SIGNATURE: |
| case SEC_ERROR_CERT_NOT_VALID: |
| // TODO(port): add an ERR_CERT_WRONG_USAGE error code. |
| case SEC_ERROR_CERT_USAGES_INVALID: |
| case SEC_ERROR_INADEQUATE_KEY_USAGE: // Key usage. |
| case SEC_ERROR_INADEQUATE_CERT_TYPE: // Extended key usage and whether |
| // the certificate is a CA. |
| case SEC_ERROR_POLICY_VALIDATION_FAILED: |
| case SEC_ERROR_PATH_LEN_CONSTRAINT_INVALID: |
| case SEC_ERROR_UNKNOWN_CRITICAL_EXTENSION: |
| case SEC_ERROR_EXTENSION_VALUE_INVALID: |
| return ERR_CERT_INVALID; |
| case SEC_ERROR_CERT_SIGNATURE_ALGORITHM_DISABLED: |
| return ERR_CERT_WEAK_SIGNATURE_ALGORITHM; |
| default: |
| LOG(WARNING) << "Unknown error " << err << " mapped to net::ERR_FAILED"; |
| return ERR_FAILED; |
| } |
| } |
| |
| // Map PORT_GetError() return values to our cert status flags. |
| CertStatus MapCertErrorToCertStatus(int err) { |
| int net_error = MapSecurityError(err); |
| return MapNetErrorToCertStatus(net_error); |
| } |
| |
| // Saves some information about the certificate chain cert_list in |
| // *verify_result. The caller MUST initialize *verify_result before calling |
| // this function. |
| // Note that cert_list[0] is the end entity certificate. |
| void GetCertChainInfo(CERTCertList* cert_list, |
| CERTCertificate* root_cert, |
| CertVerifyResult* verify_result) { |
| DCHECK(cert_list); |
| |
| CERTCertificate* verified_cert = NULL; |
| std::vector<CERTCertificate*> verified_chain; |
| size_t i = 0; |
| for (CERTCertListNode* node = CERT_LIST_HEAD(cert_list); |
| !CERT_LIST_END(node, cert_list); |
| node = CERT_LIST_NEXT(node), ++i) { |
| if (i == 0) { |
| verified_cert = node->cert; |
| } else { |
| // Because of an NSS bug, CERT_PKIXVerifyCert may chain a self-signed |
| // certificate of a root CA to another certificate of the same root CA |
| // key. Detect that error and ignore the root CA certificate. |
| // See https://bugzilla.mozilla.org/show_bug.cgi?id=721288. |
| if (node->cert->isRoot) { |
| // NOTE: isRoot doesn't mean the certificate is a trust anchor. It |
| // means the certificate is self-signed. Here we assume isRoot only |
| // implies the certificate is self-issued. |
| CERTCertListNode* next_node = CERT_LIST_NEXT(node); |
| CERTCertificate* next_cert; |
| if (!CERT_LIST_END(next_node, cert_list)) { |
| next_cert = next_node->cert; |
| } else { |
| next_cert = root_cert; |
| } |
| // Test that |node->cert| is actually a self-signed certificate |
| // whose key is equal to |next_cert|, and not a self-issued |
| // certificate signed by another key of the same CA. |
| if (next_cert && SECITEM_ItemsAreEqual(&node->cert->derPublicKey, |
| &next_cert->derPublicKey)) { |
| continue; |
| } |
| } |
| verified_chain.push_back(node->cert); |
| } |
| } |
| |
| if (root_cert) |
| verified_chain.push_back(root_cert); |
| verify_result->verified_cert = |
| X509Certificate::CreateFromHandle(verified_cert, verified_chain); |
| } |
| |
| // IsKnownRoot returns true if the given certificate is one that we believe |
| // is a standard (as opposed to user-installed) root. |
| bool IsKnownRoot(CERTCertificate* root) { |
| if (!root || !root->slot) |
| return false; |
| |
| // This magic name is taken from |
| // http://bonsai.mozilla.org/cvsblame.cgi?file=mozilla/security/nss/lib/ckfw/builtins/constants.c&rev=1.13&mark=86,89#79 |
| return 0 == strcmp(PK11_GetSlotName(root->slot), |
| "NSS Builtin Objects"); |
| } |
| |
| // Returns true if the given certificate is one of the additional trust anchors. |
| bool IsAdditionalTrustAnchor(CERTCertList* additional_trust_anchors, |
| CERTCertificate* root) { |
| if (!additional_trust_anchors || !root) |
| return false; |
| for (CERTCertListNode* node = CERT_LIST_HEAD(additional_trust_anchors); |
| !CERT_LIST_END(node, additional_trust_anchors); |
| node = CERT_LIST_NEXT(node)) { |
| if (CERT_CompareCerts(node->cert, root)) |
| return true; |
| } |
| return false; |
| } |
| |
| enum CRLSetResult { |
| kCRLSetOk, |
| kCRLSetRevoked, |
| kCRLSetUnknown, |
| }; |
| |
| // CheckRevocationWithCRLSet attempts to check each element of |cert_list| |
| // against |crl_set|. It returns: |
| // kCRLSetRevoked: if any element of the chain is known to have been revoked. |
| // kCRLSetUnknown: if there is no fresh information about the leaf |
| // certificate in the chain or if the CRLSet has expired. |
| // |
| // Only the leaf certificate is considered for coverage because some |
| // intermediates have CRLs with no revocations (after filtering) and |
| // those CRLs are pruned from the CRLSet at generation time. This means |
| // that some EV sites would otherwise take the hit of an OCSP lookup for |
| // no reason. |
| // kCRLSetOk: otherwise. |
| CRLSetResult CheckRevocationWithCRLSet(const CERTCertList* cert_list, |
| CERTCertificate* root, |
| CRLSet* crl_set) { |
| std::vector<CERTCertificate*> certs; |
| |
| if (cert_list) { |
| for (CERTCertListNode* node = CERT_LIST_HEAD(cert_list); |
| !CERT_LIST_END(node, cert_list); |
| node = CERT_LIST_NEXT(node)) { |
| certs.push_back(node->cert); |
| } |
| } |
| if (root) |
| certs.push_back(root); |
| |
| // Set to true if any errors are found, which will cause such chains to not be |
| // treated as covered by the CRLSet. |
| bool error = false; |
| // Set to the coverage state of the previous certificate. As the certificates |
| // are iterated over from root to leaf, at the end of the iteration, this |
| // indicates the coverage state of the leaf certificate. |
| bool last_covered = false; |
| |
| // We iterate from the root certificate down to the leaf, keeping track of |
| // the issuer's SPKI at each step. |
| std::string issuer_spki_hash; |
| for (std::vector<CERTCertificate*>::reverse_iterator i = certs.rbegin(); |
| i != certs.rend(); ++i) { |
| CERTCertificate* cert = *i; |
| |
| base::StringPiece der(reinterpret_cast<char*>(cert->derCert.data), |
| cert->derCert.len); |
| |
| base::StringPiece spki; |
| if (!asn1::ExtractSPKIFromDERCert(der, &spki)) { |
| NOTREACHED(); |
| error = true; |
| continue; |
| } |
| const std::string spki_hash = crypto::SHA256HashString(spki); |
| |
| base::StringPiece serial_number = base::StringPiece( |
| reinterpret_cast<char*>(cert->serialNumber.data), |
| cert->serialNumber.len); |
| |
| CRLSet::Result result = crl_set->CheckSPKI(spki_hash); |
| |
| if (result != CRLSet::REVOKED && !issuer_spki_hash.empty()) |
| result = crl_set->CheckSerial(serial_number, issuer_spki_hash); |
| |
| issuer_spki_hash = spki_hash; |
| |
| switch (result) { |
| case CRLSet::REVOKED: |
| return kCRLSetRevoked; |
| case CRLSet::UNKNOWN: |
| last_covered = false; |
| continue; |
| case CRLSet::GOOD: |
| last_covered = true; |
| continue; |
| default: |
| NOTREACHED(); |
| error = true; |
| continue; |
| } |
| } |
| |
| if (error || !last_covered || crl_set->IsExpired()) |
| return kCRLSetUnknown; |
| return kCRLSetOk; |
| } |
| |
| // Arguments for CheckChainRevocationWithCRLSet that are curried within the |
| // CERTChainVerifyCallback's isChainValidArg. |
| struct CheckChainRevocationArgs { |
| // The CRLSet to evaluate against. |
| CRLSet* crl_set = nullptr; |
| |
| // The next callback to invoke, if the CRLSet does not report any errors. |
| CERTChainVerifyCallback* next_callback = nullptr; |
| |
| // Indicates that the application callback failure was due to a CRLSet |
| // revocation, rather than due to |next_callback| rejecting it. This is |
| // used to map the error back to the proper caller-visible error code. |
| bool was_revoked = false; |
| }; |
| |
| SECStatus CheckChainRevocationWithCRLSet(void* is_chain_valid_arg, |
| const CERTCertList* current_chain, |
| PRBool* chain_ok) { |
| CHECK(is_chain_valid_arg); |
| |
| CheckChainRevocationArgs* args = |
| static_cast<CheckChainRevocationArgs*>(is_chain_valid_arg); |
| |
| CRLSetResult crlset_result = kCRLSetUnknown; |
| if (args->crl_set) { |
| crlset_result = |
| CheckRevocationWithCRLSet(current_chain, nullptr, args->crl_set); |
| } |
| |
| if (crlset_result == kCRLSetRevoked) { |
| args->was_revoked = true; |
| *chain_ok = PR_FALSE; |
| return SECSuccess; |
| } |
| args->was_revoked = false; |
| |
| *chain_ok = PR_TRUE; |
| if (!args->next_callback || !args->next_callback->isChainValid) |
| return SECSuccess; |
| |
| return (*args->next_callback->isChainValid)( |
| args->next_callback->isChainValidArg, current_chain, chain_ok); |
| } |
| |
| // Forward declarations. |
| SECStatus RetryPKIXVerifyCertWithWorkarounds( |
| CERTCertificate* cert_handle, int num_policy_oids, |
| bool cert_io_enabled, std::vector<CERTValInParam>* cvin, |
| CERTValOutParam* cvout); |
| SECOidTag GetFirstCertPolicy(CERTCertificate* cert_handle); |
| |
| // Call CERT_PKIXVerifyCert for the cert_handle. |
| // Verification results are stored in an array of CERTValOutParam. |
| // If |hard_fail| is true, and no policy_oids are supplied (eg: EV is NOT being |
| // checked), then the failure to obtain valid CRL/OCSP information for all |
| // certificates that contain CRL/OCSP URLs will cause the certificate to be |
| // treated as if it was revoked. Since failures may be caused by transient |
| // network failures or by malicious attackers, in general, hard_fail should be |
| // false. |
| // If policy_oids is not NULL and num_policy_oids is positive, policies |
| // are also checked. |
| // additional_trust_anchors is an optional list of certificates that can be |
| // trusted as anchors when building a certificate chain. |
| // Caller must initialize cvout before calling this function. |
| SECStatus PKIXVerifyCert(CERTCertificate* cert_handle, |
| bool check_revocation, |
| bool hard_fail, |
| bool cert_io_enabled, |
| const SECOidTag* policy_oids, |
| int num_policy_oids, |
| CERTCertList* additional_trust_anchors, |
| CERTChainVerifyCallback* chain_verify_callback, |
| CERTValOutParam* cvout) { |
| bool use_crl = check_revocation; |
| bool use_ocsp = check_revocation; |
| |
| PRUint64 revocation_method_flags = |
| CERT_REV_M_DO_NOT_TEST_USING_THIS_METHOD | |
| CERT_REV_M_ALLOW_NETWORK_FETCHING | |
| CERT_REV_M_IGNORE_IMPLICIT_DEFAULT_SOURCE | |
| CERT_REV_M_IGNORE_MISSING_FRESH_INFO | |
| CERT_REV_M_STOP_TESTING_ON_FRESH_INFO; |
| PRUint64 revocation_method_independent_flags = |
| CERT_REV_MI_TEST_ALL_LOCAL_INFORMATION_FIRST; |
| if (check_revocation && policy_oids && num_policy_oids > 0) { |
| // EV verification requires revocation checking. Consider the certificate |
| // revoked if we don't have revocation info. |
| // TODO(wtc): Add a bool parameter to expressly specify we're doing EV |
| // verification or we want strict revocation flags. |
| revocation_method_flags |= CERT_REV_M_REQUIRE_INFO_ON_MISSING_SOURCE; |
| revocation_method_independent_flags |= |
| CERT_REV_MI_REQUIRE_SOME_FRESH_INFO_AVAILABLE; |
| } else if (check_revocation && hard_fail) { |
| revocation_method_flags |= CERT_REV_M_FAIL_ON_MISSING_FRESH_INFO; |
| revocation_method_independent_flags |= |
| CERT_REV_MI_REQUIRE_SOME_FRESH_INFO_AVAILABLE; |
| } else { |
| revocation_method_flags |= CERT_REV_M_SKIP_TEST_ON_MISSING_SOURCE; |
| revocation_method_independent_flags |= |
| CERT_REV_MI_NO_OVERALL_INFO_REQUIREMENT; |
| } |
| PRUint64 method_flags[2]; |
| method_flags[cert_revocation_method_crl] = revocation_method_flags; |
| method_flags[cert_revocation_method_ocsp] = revocation_method_flags; |
| |
| if (use_crl) { |
| method_flags[cert_revocation_method_crl] |= |
| CERT_REV_M_TEST_USING_THIS_METHOD; |
| } |
| if (use_ocsp) { |
| method_flags[cert_revocation_method_ocsp] |= |
| CERT_REV_M_TEST_USING_THIS_METHOD; |
| } |
| |
| CERTRevocationMethodIndex preferred_revocation_methods[1]; |
| if (use_ocsp) { |
| preferred_revocation_methods[0] = cert_revocation_method_ocsp; |
| } else { |
| preferred_revocation_methods[0] = cert_revocation_method_crl; |
| } |
| |
| CERTRevocationFlags revocation_flags; |
| revocation_flags.leafTests.number_of_defined_methods = |
| arraysize(method_flags); |
| revocation_flags.leafTests.cert_rev_flags_per_method = method_flags; |
| revocation_flags.leafTests.number_of_preferred_methods = |
| arraysize(preferred_revocation_methods); |
| revocation_flags.leafTests.preferred_methods = preferred_revocation_methods; |
| revocation_flags.leafTests.cert_rev_method_independent_flags = |
| revocation_method_independent_flags; |
| |
| revocation_flags.chainTests.number_of_defined_methods = |
| arraysize(method_flags); |
| revocation_flags.chainTests.cert_rev_flags_per_method = method_flags; |
| revocation_flags.chainTests.number_of_preferred_methods = |
| arraysize(preferred_revocation_methods); |
| revocation_flags.chainTests.preferred_methods = preferred_revocation_methods; |
| revocation_flags.chainTests.cert_rev_method_independent_flags = |
| revocation_method_independent_flags; |
| |
| |
| std::vector<CERTValInParam> cvin; |
| cvin.reserve(7); |
| CERTValInParam in_param; |
| in_param.type = cert_pi_revocationFlags; |
| in_param.value.pointer.revocation = &revocation_flags; |
| cvin.push_back(in_param); |
| if (policy_oids && num_policy_oids > 0) { |
| in_param.type = cert_pi_policyOID; |
| in_param.value.arraySize = num_policy_oids; |
| in_param.value.array.oids = policy_oids; |
| cvin.push_back(in_param); |
| } |
| if (additional_trust_anchors) { |
| in_param.type = cert_pi_trustAnchors; |
| in_param.value.pointer.chain = additional_trust_anchors; |
| cvin.push_back(in_param); |
| in_param.type = cert_pi_useOnlyTrustAnchors; |
| in_param.value.scalar.b = PR_FALSE; |
| cvin.push_back(in_param); |
| } |
| if (chain_verify_callback) { |
| in_param.type = cert_pi_chainVerifyCallback; |
| in_param.value.pointer.chainVerifyCallback = chain_verify_callback; |
| cvin.push_back(in_param); |
| } |
| in_param.type = cert_pi_end; |
| cvin.push_back(in_param); |
| |
| SECStatus rv = CERT_PKIXVerifyCert(cert_handle, certificateUsageSSLServer, |
| &cvin[0], cvout, NULL); |
| if (rv != SECSuccess) { |
| rv = RetryPKIXVerifyCertWithWorkarounds(cert_handle, num_policy_oids, |
| cert_io_enabled, &cvin, cvout); |
| } |
| return rv; |
| } |
| |
| // PKIXVerifyCert calls this function to work around some bugs in |
| // CERT_PKIXVerifyCert. All the arguments of this function are either the |
| // arguments or local variables of PKIXVerifyCert. |
| SECStatus RetryPKIXVerifyCertWithWorkarounds( |
| CERTCertificate* cert_handle, int num_policy_oids, |
| bool cert_io_enabled, std::vector<CERTValInParam>* cvin, |
| CERTValOutParam* cvout) { |
| // We call this function when the first CERT_PKIXVerifyCert call in |
| // PKIXVerifyCert failed, so we initialize |rv| to SECFailure. |
| SECStatus rv = SECFailure; |
| int nss_error = PORT_GetError(); |
| CERTValInParam in_param; |
| |
| // If we get SEC_ERROR_UNKNOWN_ISSUER, we may be missing an intermediate |
| // CA certificate, so we retry with cert_pi_useAIACertFetch. |
| // cert_pi_useAIACertFetch has several bugs in its error handling and |
| // error reporting (NSS bug 528743), so we don't use it by default. |
| // Note: When building a certificate chain, CERT_PKIXVerifyCert may |
| // incorrectly pick a CA certificate with the same subject name as the |
| // missing intermediate CA certificate, and fail with the |
| // SEC_ERROR_BAD_SIGNATURE error (NSS bug 524013), so we also retry with |
| // cert_pi_useAIACertFetch on SEC_ERROR_BAD_SIGNATURE. |
| if (cert_io_enabled && |
| (nss_error == SEC_ERROR_UNKNOWN_ISSUER || |
| nss_error == SEC_ERROR_BAD_SIGNATURE)) { |
| DCHECK_EQ(cvin->back().type, cert_pi_end); |
| cvin->pop_back(); |
| in_param.type = cert_pi_useAIACertFetch; |
| in_param.value.scalar.b = PR_TRUE; |
| cvin->push_back(in_param); |
| in_param.type = cert_pi_end; |
| cvin->push_back(in_param); |
| rv = CERT_PKIXVerifyCert(cert_handle, certificateUsageSSLServer, |
| &(*cvin)[0], cvout, NULL); |
| if (rv == SECSuccess) |
| return rv; |
| int new_nss_error = PORT_GetError(); |
| if (new_nss_error == SEC_ERROR_INVALID_ARGS || |
| new_nss_error == SEC_ERROR_UNKNOWN_AIA_LOCATION_TYPE || |
| new_nss_error == SEC_ERROR_BAD_INFO_ACCESS_LOCATION || |
| new_nss_error == SEC_ERROR_BAD_HTTP_RESPONSE || |
| new_nss_error == SEC_ERROR_BAD_LDAP_RESPONSE || |
| !IS_SEC_ERROR(new_nss_error)) { |
| // Use the original error code because of cert_pi_useAIACertFetch's |
| // bad error reporting. |
| PORT_SetError(nss_error); |
| return rv; |
| } |
| nss_error = new_nss_error; |
| } |
| |
| // If an intermediate CA certificate has requireExplicitPolicy in its |
| // policyConstraints extension, CERT_PKIXVerifyCert fails with |
| // SEC_ERROR_POLICY_VALIDATION_FAILED because we didn't specify any |
| // certificate policy (NSS bug 552775). So we retry with the certificate |
| // policy found in the server certificate. |
| if (nss_error == SEC_ERROR_POLICY_VALIDATION_FAILED && |
| num_policy_oids == 0) { |
| SECOidTag policy = GetFirstCertPolicy(cert_handle); |
| if (policy != SEC_OID_UNKNOWN) { |
| DCHECK_EQ(cvin->back().type, cert_pi_end); |
| cvin->pop_back(); |
| in_param.type = cert_pi_policyOID; |
| in_param.value.arraySize = 1; |
| in_param.value.array.oids = &policy; |
| cvin->push_back(in_param); |
| in_param.type = cert_pi_end; |
| cvin->push_back(in_param); |
| rv = CERT_PKIXVerifyCert(cert_handle, certificateUsageSSLServer, |
| &(*cvin)[0], cvout, NULL); |
| if (rv != SECSuccess) { |
| // Use the original error code. |
| PORT_SetError(nss_error); |
| } |
| } |
| } |
| |
| return rv; |
| } |
| |
| // Decodes the certificatePolicies extension of the certificate. Returns |
| // NULL if the certificate doesn't have the extension or the extension can't |
| // be decoded. The returned value must be freed with a |
| // CERT_DestroyCertificatePoliciesExtension call. |
| CERTCertificatePolicies* DecodeCertPolicies( |
| CERTCertificate* cert_handle) { |
| SECItem policy_ext; |
| SECStatus rv = CERT_FindCertExtension(cert_handle, |
| SEC_OID_X509_CERTIFICATE_POLICIES, |
| &policy_ext); |
| if (rv != SECSuccess) |
| return NULL; |
| CERTCertificatePolicies* policies = |
| CERT_DecodeCertificatePoliciesExtension(&policy_ext); |
| SECITEM_FreeItem(&policy_ext, PR_FALSE); |
| return policies; |
| } |
| |
| // Returns the OID tag for the first certificate policy in the certificate's |
| // certificatePolicies extension. Returns SEC_OID_UNKNOWN if the certificate |
| // has no certificate policy. |
| SECOidTag GetFirstCertPolicy(CERTCertificate* cert_handle) { |
| ScopedCERTCertificatePolicies policies(DecodeCertPolicies(cert_handle)); |
| if (!policies.get()) |
| return SEC_OID_UNKNOWN; |
| |
| CERTPolicyInfo* policy_info = policies->policyInfos[0]; |
| if (!policy_info) |
| return SEC_OID_UNKNOWN; |
| if (policy_info->oid != SEC_OID_UNKNOWN) |
| return policy_info->oid; |
| |
| // The certificate policy is unknown to NSS. We need to create a dynamic |
| // OID tag for the policy. |
| SECOidData od; |
| od.oid.len = policy_info->policyID.len; |
| od.oid.data = policy_info->policyID.data; |
| od.offset = SEC_OID_UNKNOWN; |
| // NSS doesn't allow us to pass an empty description, so I use a hardcoded, |
| // default description here. The description doesn't need to be unique for |
| // each OID. |
| od.desc = "a certificate policy"; |
| od.mechanism = CKM_INVALID_MECHANISM; |
| od.supportedExtension = INVALID_CERT_EXTENSION; |
| return SECOID_AddEntry(&od); |
| } |
| |
| HashValue CertPublicKeyHashSHA1(CERTCertificate* cert) { |
| HashValue hash(HASH_VALUE_SHA1); |
| SECStatus rv = HASH_HashBuf(HASH_AlgSHA1, hash.data(), |
| cert->derPublicKey.data, cert->derPublicKey.len); |
| DCHECK_EQ(SECSuccess, rv); |
| return hash; |
| } |
| |
| HashValue CertPublicKeyHashSHA256(CERTCertificate* cert) { |
| HashValue hash(HASH_VALUE_SHA256); |
| SECStatus rv = HASH_HashBuf(HASH_AlgSHA256, hash.data(), |
| cert->derPublicKey.data, cert->derPublicKey.len); |
| DCHECK_EQ(rv, SECSuccess); |
| return hash; |
| } |
| |
| void AppendPublicKeyHashes(CERTCertList* cert_list, |
| CERTCertificate* root_cert, |
| HashValueVector* hashes) { |
| for (CERTCertListNode* node = CERT_LIST_HEAD(cert_list); |
| !CERT_LIST_END(node, cert_list); |
| node = CERT_LIST_NEXT(node)) { |
| hashes->push_back(CertPublicKeyHashSHA1(node->cert)); |
| hashes->push_back(CertPublicKeyHashSHA256(node->cert)); |
| } |
| if (root_cert) { |
| hashes->push_back(CertPublicKeyHashSHA1(root_cert)); |
| hashes->push_back(CertPublicKeyHashSHA256(root_cert)); |
| } |
| } |
| |
| // Returns true if |cert_handle| contains a policy OID that is an EV policy |
| // OID according to |metadata|, storing the resulting policy OID in |
| // |*ev_policy_oid|. A true return is not sufficient to establish that a |
| // certificate is EV, but a false return is sufficient to establish the |
| // certificate cannot be EV. |
| bool IsEVCandidate(EVRootCAMetadata* metadata, |
| CERTCertificate* cert_handle, |
| SECOidTag* ev_policy_oid) { |
| *ev_policy_oid = SEC_OID_UNKNOWN; |
| DCHECK(cert_handle); |
| ScopedCERTCertificatePolicies policies(DecodeCertPolicies(cert_handle)); |
| if (!policies.get()) |
| return false; |
| |
| CERTPolicyInfo** policy_infos = policies->policyInfos; |
| while (*policy_infos != NULL) { |
| CERTPolicyInfo* policy_info = *policy_infos++; |
| // If the Policy OID is unknown, that implicitly means it has not been |
| // registered as an EV policy. |
| if (policy_info->oid == SEC_OID_UNKNOWN) |
| continue; |
| if (metadata->IsEVPolicyOID(policy_info->oid)) { |
| *ev_policy_oid = policy_info->oid; |
| |
| // De-prioritize the CA/Browser forum Extended Validation policy |
| // (2.23.140.1.1). See crbug.com/705285. |
| if (!EVRootCAMetadata::IsCaBrowserForumEvOid(policy_info->oid)) |
| break; |
| } |
| } |
| |
| return *ev_policy_oid != SEC_OID_UNKNOWN; |
| } |
| |
| // Studied Mozilla's code (esp. security/manager/ssl/src/nsIdentityChecking.cpp |
| // and nsNSSCertHelper.cpp) to learn how to verify EV certificate. |
| // TODO(wtc): A possible optimization is that we get the trust anchor from |
| // the first PKIXVerifyCert call. We look up the EV policy for the trust |
| // anchor. If the trust anchor has no EV policy, we know the cert isn't EV. |
| // Otherwise, we pass just that EV policy (as opposed to all the EV policies) |
| // to the second PKIXVerifyCert call. |
| bool VerifyEV(CERTCertificate* cert_handle, |
| int flags, |
| CRLSet* crl_set, |
| bool rev_checking_enabled, |
| EVRootCAMetadata* metadata, |
| SECOidTag ev_policy_oid, |
| CERTCertList* additional_trust_anchors, |
| CERTChainVerifyCallback* chain_verify_callback) { |
| CERTValOutParam cvout[3]; |
| int cvout_index = 0; |
| cvout[cvout_index].type = cert_po_certList; |
| cvout[cvout_index].value.pointer.chain = NULL; |
| int cvout_cert_list_index = cvout_index; |
| cvout_index++; |
| cvout[cvout_index].type = cert_po_trustAnchor; |
| cvout[cvout_index].value.pointer.cert = NULL; |
| int cvout_trust_anchor_index = cvout_index; |
| cvout_index++; |
| cvout[cvout_index].type = cert_po_end; |
| ScopedCERTValOutParam scoped_cvout(cvout); |
| |
| SECStatus status = PKIXVerifyCert( |
| cert_handle, |
| rev_checking_enabled, |
| true, /* hard fail is implied in EV. */ |
| flags & CertVerifier::VERIFY_CERT_IO_ENABLED, |
| &ev_policy_oid, |
| 1, |
| additional_trust_anchors, |
| chain_verify_callback, |
| cvout); |
| if (status != SECSuccess) |
| return false; |
| |
| CERTCertificate* root_ca = |
| cvout[cvout_trust_anchor_index].value.pointer.cert; |
| if (root_ca == NULL) |
| return false; |
| |
| // This second PKIXVerifyCert call could have found a different certification |
| // path and one or more of the certificates on this new path, that weren't on |
| // the old path, might have been revoked. |
| if (crl_set) { |
| CRLSetResult crl_set_result = CheckRevocationWithCRLSet( |
| cvout[cvout_cert_list_index].value.pointer.chain, |
| cvout[cvout_trust_anchor_index].value.pointer.cert, |
| crl_set); |
| if (crl_set_result == kCRLSetRevoked) |
| return false; |
| } |
| |
| SHA1HashValue weak_fingerprint; |
| base::SHA1HashBytes(root_ca->derCert.data, root_ca->derCert.len, |
| weak_fingerprint.data); |
| return metadata->HasEVPolicyOID(weak_fingerprint, ev_policy_oid); |
| } |
| |
| CERTCertList* CertificateListToCERTCertList(const CertificateList& list) { |
| CERTCertList* result = CERT_NewCertList(); |
| for (size_t i = 0; i < list.size(); ++i) { |
| CERTCertificate* cert = list[i]->os_cert_handle(); |
| CERT_AddCertToListTail(result, CERT_DupCertificate(cert)); |
| } |
| return result; |
| } |
| |
| } // namespace |
| |
| CertVerifyProcNSS::CertVerifyProcNSS() |
| : cache_ocsp_response_from_side_channel_( |
| reinterpret_cast<CacheOCSPResponseFromSideChannelFunction>( |
| dlsym(RTLD_DEFAULT, "CERT_CacheOCSPResponseFromSideChannel"))) |
| { |
| } |
| |
| CertVerifyProcNSS::~CertVerifyProcNSS() {} |
| |
| bool CertVerifyProcNSS::SupportsAdditionalTrustAnchors() const { |
| return true; |
| } |
| |
| bool CertVerifyProcNSS::SupportsOCSPStapling() const { |
| return cache_ocsp_response_from_side_channel_; |
| } |
| |
| int CertVerifyProcNSS::VerifyInternalImpl( |
| X509Certificate* cert, |
| const std::string& hostname, |
| const std::string& ocsp_response, |
| int flags, |
| CRLSet* crl_set, |
| const CertificateList& additional_trust_anchors, |
| CERTChainVerifyCallback* chain_verify_callback, |
| CertVerifyResult* verify_result) { |
| CERTCertificate* cert_handle = cert->os_cert_handle(); |
| |
| if (!ocsp_response.empty() && cache_ocsp_response_from_side_channel_) { |
| // Note: NSS uses a thread-safe global hash table, so this call will |
| // affect any concurrent verification operations on |cert| or copies of |
| // the same certificate. This is an unavoidable limitation of NSS's OCSP |
| // API. |
| SECItem ocsp_response_item; |
| ocsp_response_item.data = reinterpret_cast<unsigned char*>( |
| const_cast<char*>(ocsp_response.data())); |
| ocsp_response_item.len = ocsp_response.size(); |
| cache_ocsp_response_from_side_channel_(CERT_GetDefaultCertDB(), cert_handle, |
| PR_Now(), &ocsp_response_item, |
| nullptr); |
| } |
| |
| // Setup a callback to call into CheckChainRevocationWithCRLSet with the |
| // current CRLSet. If the CRLSet revokes a given chain, |was_revoked| |
| // will be set to true. |
| // The same callback and args are used for every invocation of |
| // PKIXVerifyCert, as CheckChainRevocationWithCRLSet handles resetting |
| // |was_revoked| as necessary. |
| CheckChainRevocationArgs check_chain_revocation_args; |
| check_chain_revocation_args.crl_set = crl_set; |
| check_chain_revocation_args.next_callback = chain_verify_callback; |
| |
| CERTChainVerifyCallback crlset_callback; |
| memset(&crlset_callback, 0, sizeof(crlset_callback)); |
| crlset_callback.isChainValid = &CheckChainRevocationWithCRLSet; |
| crlset_callback.isChainValidArg = |
| static_cast<void*>(&check_chain_revocation_args); |
| |
| // Make sure that the cert is valid now. |
| SECCertTimeValidity validity = CERT_CheckCertValidTimes( |
| cert_handle, PR_Now(), PR_TRUE); |
| if (validity != secCertTimeValid) |
| verify_result->cert_status |= CERT_STATUS_DATE_INVALID; |
| |
| CERTValOutParam cvout[3]; |
| int cvout_index = 0; |
| cvout[cvout_index].type = cert_po_certList; |
| cvout[cvout_index].value.pointer.chain = NULL; |
| int cvout_cert_list_index = cvout_index; |
| cvout_index++; |
| cvout[cvout_index].type = cert_po_trustAnchor; |
| cvout[cvout_index].value.pointer.cert = NULL; |
| int cvout_trust_anchor_index = cvout_index; |
| cvout_index++; |
| cvout[cvout_index].type = cert_po_end; |
| ScopedCERTValOutParam scoped_cvout(cvout); |
| |
| EVRootCAMetadata* metadata = EVRootCAMetadata::GetInstance(); |
| SECOidTag ev_policy_oid = SEC_OID_UNKNOWN; |
| bool is_ev_candidate = |
| (flags & CertVerifier::VERIFY_EV_CERT) && |
| IsEVCandidate(metadata, cert_handle, &ev_policy_oid); |
| bool cert_io_enabled = flags & CertVerifier::VERIFY_CERT_IO_ENABLED; |
| bool check_revocation = |
| cert_io_enabled && |
| (flags & CertVerifier::VERIFY_REV_CHECKING_ENABLED); |
| if (check_revocation) |
| verify_result->cert_status |= CERT_STATUS_REV_CHECKING_ENABLED; |
| |
| ScopedCERTCertList trust_anchors; |
| if (!additional_trust_anchors.empty()) { |
| trust_anchors.reset( |
| CertificateListToCERTCertList(additional_trust_anchors)); |
| } |
| |
| SECStatus status = |
| PKIXVerifyCert(cert_handle, check_revocation, false, cert_io_enabled, |
| NULL, 0, trust_anchors.get(), &crlset_callback, cvout); |
| |
| if (status == SECSuccess && |
| (flags & CertVerifier::VERIFY_REV_CHECKING_REQUIRED_LOCAL_ANCHORS) && |
| !IsKnownRoot(cvout[cvout_trust_anchor_index].value.pointer.cert)) { |
| // TODO(rsleevi): Optimize this by supplying the constructed chain to |
| // libpkix via cvin. Omitting for now, due to lack of coverage in upstream |
| // NSS tests for that feature. |
| scoped_cvout.Clear(); |
| verify_result->cert_status |= CERT_STATUS_REV_CHECKING_ENABLED; |
| status = PKIXVerifyCert(cert_handle, true, true, cert_io_enabled, NULL, 0, |
| trust_anchors.get(), &crlset_callback, cvout); |
| } |
| |
| if (status == SECSuccess) { |
| AppendPublicKeyHashes(cvout[cvout_cert_list_index].value.pointer.chain, |
| cvout[cvout_trust_anchor_index].value.pointer.cert, |
| &verify_result->public_key_hashes); |
| |
| verify_result->is_issued_by_known_root = |
| IsKnownRoot(cvout[cvout_trust_anchor_index].value.pointer.cert); |
| verify_result->is_issued_by_additional_trust_anchor = |
| IsAdditionalTrustAnchor( |
| trust_anchors.get(), |
| cvout[cvout_trust_anchor_index].value.pointer.cert); |
| |
| GetCertChainInfo(cvout[cvout_cert_list_index].value.pointer.chain, |
| cvout[cvout_trust_anchor_index].value.pointer.cert, |
| verify_result); |
| } |
| |
| CRLSetResult crl_set_result = kCRLSetUnknown; |
| if (crl_set) { |
| if (status == SECSuccess) { |
| // Reverify the returned chain; NSS should have already called |
| // CheckChainRevocationWithCRLSet prior to returning, but given the |
| // edge cases (self-signed certs that are trusted; cached chains; |
| // unreadable code), this is more about defense in depth than |
| // functional necessity. |
| crl_set_result = CheckRevocationWithCRLSet( |
| cvout[cvout_cert_list_index].value.pointer.chain, |
| cvout[cvout_trust_anchor_index].value.pointer.cert, crl_set); |
| if (crl_set_result == kCRLSetRevoked) { |
| PORT_SetError(SEC_ERROR_REVOKED_CERTIFICATE); |
| status = SECFailure; |
| } |
| } else if (PORT_GetError() == SEC_ERROR_APPLICATION_CALLBACK_ERROR && |
| check_chain_revocation_args.was_revoked) { |
| // If a CRLSet was supplied, and the error was an application callback |
| // error, then it was directed through the CRLSet code and that |
| // particular chain was revoked. |
| PORT_SetError(SEC_ERROR_REVOKED_CERTIFICATE); |
| } |
| } |
| |
| if (status != SECSuccess) { |
| int err = PORT_GetError(); |
| LOG(ERROR) << "CERT_PKIXVerifyCert for " << hostname |
| << " failed err=" << err; |
| // CERT_PKIXVerifyCert rerports the wrong error code for |
| // expired certificates (NSS bug 491174) |
| if (err == SEC_ERROR_CERT_NOT_VALID && |
| (verify_result->cert_status & CERT_STATUS_DATE_INVALID)) |
| err = SEC_ERROR_EXPIRED_CERTIFICATE; |
| CertStatus cert_status = MapCertErrorToCertStatus(err); |
| if (cert_status) { |
| verify_result->cert_status |= cert_status; |
| return MapCertStatusToNetError(verify_result->cert_status); |
| } |
| // |err| is not a certificate error. |
| return MapSecurityError(err); |
| } |
| |
| if (IsCertStatusError(verify_result->cert_status)) |
| return MapCertStatusToNetError(verify_result->cert_status); |
| |
| if ((flags & CertVerifier::VERIFY_EV_CERT) && is_ev_candidate) { |
| check_revocation |= |
| crl_set_result != kCRLSetOk && |
| cert_io_enabled && |
| (flags & CertVerifier::VERIFY_REV_CHECKING_ENABLED_EV_ONLY); |
| if (check_revocation) |
| verify_result->cert_status |= CERT_STATUS_REV_CHECKING_ENABLED; |
| |
| if (VerifyEV(cert_handle, flags, crl_set, check_revocation, metadata, |
| ev_policy_oid, trust_anchors.get(), &crlset_callback)) { |
| verify_result->cert_status |= CERT_STATUS_IS_EV; |
| } |
| } |
| |
| return OK; |
| } |
| |
| int CertVerifyProcNSS::VerifyInternal( |
| X509Certificate* cert, |
| const std::string& hostname, |
| const std::string& ocsp_response, |
| int flags, |
| CRLSet* crl_set, |
| const CertificateList& additional_trust_anchors, |
| CertVerifyResult* verify_result) { |
| return VerifyInternalImpl(cert, hostname, ocsp_response, flags, crl_set, |
| additional_trust_anchors, |
| NULL, // chain_verify_callback |
| verify_result); |
| } |
| |
| } // namespace net |
