security/ct/CTLogVerifier.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef CTLogVerifier_h
   8 #define CTLogVerifier_h
   9
  10 #include <memory>
  11
  12 #include "CTLog.h"
  13 #include "CTUtils.h"
  14 #include "SignedCertificateTimestamp.h"
  15 #include "mozpkix/Input.h"
  16 #include "mozpkix/Result.h"
  17 #include "mozpkix/pkix.h"
  18
  19 namespace mozilla {
  20 namespace ct {
  21
  22 // Verifies Signed Certificate Timestamps (SCTs) provided by a specific log
  23 // using the public key of that log. Assumes the SCT being verified
  24 // matches the log by log key ID and signature parameters (an error is returned
  25 // otherwise).
  26 // The verification functions return Success if the provided SCT has passed
  27 // verification, ERROR_BAD_SIGNATURE if failed verification, or other result
  28 // on error.
  29 class CTLogVerifier {
  30  public:
  31   CTLogVerifier();
  32
  33   // Initializes the verifier with log-specific information. Only the public
  34   // key is used for verification, other parameters are purely informational.
  35   // |subjectPublicKeyInfo| is a DER-encoded SubjectPublicKeyInfo.
  36   // |operatorId| The numeric ID of the log operator as assigned at
  37   // https://www.certificate-transparency.org/known-logs .
  38   // |logStatus| Either "Included" or "Disqualified".
  39   // |disqualificationTime| Disqualification timestamp (for disqualified logs).
  40   // An error is returned if |subjectPublicKeyInfo| refers to an unsupported
  41   // public key.
  42   pkix::Result Init(pkix::Input subjectPublicKeyInfo,
  43                     CTLogOperatorId operatorId, CTLogStatus logStatus,
  44                     uint64_t disqualificationTime);
  45
  46   // Returns the log's key ID, which is a SHA256 hash of its public key.
  47   // See RFC 6962, Section 3.2.
  48   const Buffer& keyId() const { return mKeyId; }
  49
  50   CTLogOperatorId operatorId() const { return mOperatorId; }
  51   bool isDisqualified() const { return mDisqualified; }
  52   uint64_t disqualificationTime() const { return mDisqualificationTime; }
  53
  54   // Verifies that |sct| contains a valid signature for |entry|.
  55   // |sct| must be signed by the verifier's log.
  56   pkix::Result Verify(const LogEntry& entry,
  57                       const SignedCertificateTimestamp& sct);
  58
  59   // Returns true if the signature and hash algorithms in |signature|
  60   // match those of the log.
  61   bool SignatureParametersMatch(const DigitallySigned& signature);
  62
  63  private:
  64   // Performs the underlying verification using the log's public key. Note
  65   // that |signature| contains the raw signature data (i.e. without any
  66   // DigitallySigned struct encoding).
  67   // Returns Success if passed verification, ERROR_BAD_SIGNATURE if failed
  68   // verification, or other result on error.
  69   pkix::Result VerifySignature(pkix::Input data, pkix::Input signature);
  70   pkix::Result VerifySignature(const Buffer& data, const Buffer& signature);
  71
  72   // mPublicECKey works around an architectural deficiency in NSS. In the case
  73   // of EC, if we don't create, import, and cache this key, NSS will import and
  74   // verify it every signature verification, which is slow. For RSA, this is
  75   // unused and will be null.
  76   UniqueSECKEYPublicKey mPublicECKey;
  77   Buffer mSubjectPublicKeyInfo;
  78   Buffer mKeyId;
  79   DigitallySigned::SignatureAlgorithm mSignatureAlgorithm;
  80   CTLogOperatorId mOperatorId;
  81   bool mDisqualified;
  82   uint64_t mDisqualificationTime;
  83 };
  84
  85 }  // namespace ct
  86 }  // namespace mozilla
  87
  88 #endif  // CTLogVerifier_h