net/cert/crl_set.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef NET_CERT_CRL_SET_H_
   6 #define NET_CERT_CRL_SET_H_
   7
   8 #include <map>
   9 #include <string>
  10 #include <utility>
  11 #include <vector>
  12
  13 #include "base/memory/ref_counted.h"
  14 #include "base/strings/string_piece.h"
  15 #include "net/base/net_export.h"
  16 #include "net/cert/x509_cert_types.h"
  17
  18 namespace base {
  19 class DictionaryValue;
  20 }
  21
  22 namespace net {
  23
  24 // A CRLSet is a structure that lists the serial numbers of revoked
  25 // certificates from a number of issuers where issuers are identified by the
  26 // SHA256 of their SubjectPublicKeyInfo.
  27 class NET_EXPORT CRLSet : public base::RefCountedThreadSafe<CRLSet> {
  28  public:
  29   enum Result {
  30     REVOKED,  // the certificate should be rejected.
  31     UNKNOWN,  // the CRL for the certificate is not included in the set.
  32     GOOD,     // the certificate is not listed.
  33   };
  34
  35   // Parse parses the bytes in |data| and, on success, puts a new CRLSet in
  36   // |out_crl_set| and returns true.
  37   static bool Parse(base::StringPiece data,
  38                     scoped_refptr<CRLSet>* out_crl_set);
  39
  40   // CheckSPKI checks whether the given SPKI has been listed as blocked.
  41   //   spki_hash: the SHA256 of the SubjectPublicKeyInfo of the certificate.
  42   Result CheckSPKI(const base::StringPiece& spki_hash) const;
  43
  44   // CheckSerial returns the information contained in the set for a given
  45   // certificate:
  46   //   serial_number: the serial number of the certificate
  47   //   issuer_spki_hash: the SHA256 of the SubjectPublicKeyInfo of the CRL
  48   //       signer
  49   Result CheckSerial(
  50       const base::StringPiece& serial_number,
  51       const base::StringPiece& issuer_spki_hash) const;
  52
  53   // IsExpired returns true iff the current time is past the NotAfter time
  54   // specified in the CRLSet.
  55   bool IsExpired() const;
  56
  57   // ApplyDelta returns a new CRLSet in |out_crl_set| that is the result of
  58   // updating the current CRL set with the delta information in |delta_bytes|.
  59   bool ApplyDelta(const base::StringPiece& delta_bytes,
  60                   scoped_refptr<CRLSet>* out_crl_set);
  61
  62   // GetIsDeltaUpdate extracts the header from |bytes|, sets *is_delta to
  63   // whether |bytes| is a delta CRL set or not and returns true. In the event
  64   // of a parse error, it returns false.
  65   static bool GetIsDeltaUpdate(const base::StringPiece& bytes, bool *is_delta);
  66
  67   // Serialize returns a string of bytes suitable for passing to Parse. Parsing
  68   // and serializing a CRLSet is a lossless operation - the resulting bytes
  69   // will be equal.
  70   std::string Serialize() const;
  71
  72   // sequence returns the sequence number of this CRL set. CRL sets generated
  73   // by the same source are given strictly monotonically increasing sequence
  74   // numbers.
  75   uint32 sequence() const;
  76
  77   // CRLList contains a list of (issuer SPKI hash, revoked serial numbers)
  78   // pairs.
  79   typedef std::vector< std::pair<std::string, std::vector<std::string> > >
  80       CRLList;
  81
  82   // crls returns the internal state of this CRLSet. It should only be used in
  83   // testing.
  84   const CRLList& crls() const;
  85
  86   // EmptyCRLSetForTesting returns a valid, but empty, CRLSet for unit tests.
  87   static CRLSet* EmptyCRLSetForTesting();
  88
  89   // ExpiredCRLSetForTesting returns a expired, empty CRLSet for unit tests.
  90   static CRLSet* ExpiredCRLSetForTesting();
  91
  92   // ForTesting returns a CRLSet for testing. If |is_expired| is true, calling
  93   // IsExpired on the result will return true. If |issuer_spki| is not NULL,
  94   // the CRLSet will cover certificates issued by that SPKI. If |serial_number|
  95   // is not emtpy, then that big-endian serial number will be considered to
  96   // have been revoked by |issuer_spki|.
  97   static CRLSet* ForTesting(bool is_expired,
  98                             const SHA256HashValue* issuer_spki,
  99                             const std::string& serial_number);
 100
 101  private:
 102   CRLSet();
 103   ~CRLSet();
 104
 105   friend class base::RefCountedThreadSafe<CRLSet>;
 106
 107   // CopyBlockedSPKIsFromHeader sets |blocked_spkis_| to the list of values
 108   // from "BlockedSPKIs" in |header_dict|.
 109   bool CopyBlockedSPKIsFromHeader(base::DictionaryValue* header_dict);
 110
 111   uint32 sequence_;
 112   CRLList crls_;
 113   // not_after_ contains the time, in UNIX epoch seconds, after which the
 114   // CRLSet should be considered stale, or 0 if no such time was given.
 115   uint64 not_after_;
 116   // crls_index_by_issuer_ maps from issuer SPKI hashes to the index in |crls_|
 117   // where the information for that issuer can be found. We have both |crls_|
 118   // and |crls_index_by_issuer_| because, when applying a delta update, we need
 119   // to identify a CRL by index.
 120   std::map<std::string, size_t> crls_index_by_issuer_;
 121   // blocked_spkis_ contains the SHA256 hashes of SPKIs which are to be blocked
 122   // no matter where in a certificate chain they might appear.
 123   std::vector<std::string> blocked_spkis_;
 124 };
 125
 126 }  // namespace net
 127
 128 #endif  // NET_CERT_CRL_SET_H_