michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=8 sts=2 et sw=2 tw=80: */
michael@0: /* Copyright 2013 Mozilla Foundation
michael@0:  *
michael@0:  * Licensed under the Apache License, Version 2.0 (the "License");
michael@0:  * you may not use this file except in compliance with the License.
michael@0:  * You may obtain a copy of the License at
michael@0:  *
michael@0:  *     http://www.apache.org/licenses/LICENSE-2.0
michael@0:  *
michael@0:  * Unless required by applicable law or agreed to in writing, software
michael@0:  * distributed under the License is distributed on an "AS IS" BASIS,
michael@0:  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
michael@0:  * See the License for the specific language governing permissions and
michael@0:  * limitations under the License.
michael@0:  */
michael@0: 
michael@0: #include "pkix/pkix.h"
michael@0: 
michael@0: #include <limits>
michael@0: #include <stdint.h>
michael@0: 
michael@0: #include "cert.h"
michael@0: #include "cryptohi.h"
michael@0: #include "prerror.h"
michael@0: #include "secerr.h"
michael@0: 
michael@0: namespace mozilla { namespace pkix {
michael@0: 
michael@0: SECStatus
michael@0: VerifySignedData(const CERTSignedData* sd, const CERTCertificate* cert,
michael@0:                  void* pkcs11PinArg)
michael@0: {
michael@0:   if (!sd || !sd->data.data || !sd->signatureAlgorithm.algorithm.data ||
michael@0:       !sd->signature.data || !cert) {
michael@0:     PR_NOT_REACHED("invalid args to VerifySignedData");
michael@0:     PR_SetError(SEC_ERROR_INVALID_ARGS, 0);
michael@0:     return SECFailure;
michael@0:   }
michael@0: 
michael@0:   // See bug 921585.
michael@0:   if (sd->data.len > static_cast<unsigned int>(std::numeric_limits<int>::max())) {
michael@0:     PR_SetError(SEC_ERROR_INVALID_ARGS, 0);
michael@0:     return SECFailure;
michael@0:   }
michael@0: 
michael@0:   // convert sig->len from bit counts to byte count.
michael@0:   SECItem sig = sd->signature;
michael@0:   DER_ConvertBitString(&sig);
michael@0: 
michael@0:   // Use SECKEY_ExtractPublicKey instead of CERT_ExtractPublicKey because
michael@0:   // CERT_ExtractPublicKey would try to do (EC)DSA parameter inheritance, using
michael@0:   // the classic (wrong) NSS path building logic. We intentionally do not
michael@0:   // support parameter inheritance.
michael@0:   ScopedSECKEYPublicKey
michael@0:     pubKey(SECKEY_ExtractPublicKey(&cert->subjectPublicKeyInfo));
michael@0:   if (!pubKey) {
michael@0:     return SECFailure;
michael@0:   }
michael@0: 
michael@0:   SECOidTag hashAlg;
michael@0:   if (VFY_VerifyDataWithAlgorithmID(sd->data.data, static_cast<int>(sd->data.len),
michael@0:                                     pubKey.get(), &sig, &sd->signatureAlgorithm,
michael@0:                                     &hashAlg, pkcs11PinArg) != SECSuccess) {
michael@0:     return SECFailure;
michael@0:   }
michael@0: 
michael@0:   // TODO: Ideally, we would do this check before we call
michael@0:   // VFY_VerifyDataWithAlgorithmID. But, VFY_VerifyDataWithAlgorithmID gives us
michael@0:   // the hash algorithm so it is more convenient to do things in this order.
michael@0:   uint32_t policy;
michael@0:   if (NSS_GetAlgorithmPolicy(hashAlg, &policy) != SECSuccess) {
michael@0:     return SECFailure;
michael@0:   }
michael@0: 
michael@0:   // XXX: I'm not sure why there isn't NSS_USE_ALG_IN_SSL_SIGNATURE, but there
michael@0:   // isn't. Since we don't know the context in which we're being called, be as
michael@0:   // strict as we can be given the NSS API that is available.
michael@0:   static const uint32_t requiredPolicy = NSS_USE_ALG_IN_CERT_SIGNATURE |
michael@0:                                          NSS_USE_ALG_IN_CMS_SIGNATURE;
michael@0:   if ((policy & requiredPolicy) != requiredPolicy) {
michael@0:     PR_SetError(SEC_ERROR_CERT_SIGNATURE_ALGORITHM_DISABLED, 0);
michael@0:     return SECFailure;
michael@0:   }
michael@0: 
michael@0:   return SECSuccess;
michael@0: }
michael@0: 
michael@0: } } // namespace mozilla::pkix