src/checkpoints.h

   1 // Copyright (c) 2009-2012 The Bitcoin developers
   2 // Distributed under the MIT/X11 software license, see the accompanying
   3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   4 #ifndef BITCOIN_CHECKPOINT_H
   5 #define  BITCOIN_CHECKPOINT_H
   6
   7 #include <map>
   8 #include "util.h"
   9 #include "net.h"
  10
  11 // max 1 hour before latest block
  12 static const int64_t CHECKPOINT_MAX_SPAN = nOneHour;
  13
  14 #ifdef WIN32
  15 #undef STRICT
  16 #undef PERMISSIVE
  17 #undef ADVISORY
  18 #endif
  19
  20 class uint256;
  21 class CBlockIndex;
  22 class CSyncCheckpoint;
  23
  24 /** Block-chain checkpoints are compiled-in sanity checks.
  25  * They are updated every release or three.
  26  */
  27 namespace Checkpoints
  28 {
  29     /** Checkpointing mode */
  30     enum CPMode
  31     {
  32         // Scrict checkpoints policy, perform conflicts verification and resolve conflicts
  33         STRICT = 0,
  34         // Advisory checkpoints policy, perform conflicts verification but don't try to resolve them
  35         ADVISORY = 1,
  36         // Permissive checkpoints policy, don't perform any checking
  37         PERMISSIVE = 2
  38     };
  39
  40     // Returns true if block passes checkpoint checks
  41     bool CheckHardened(int nHeight, const uint256& hash);
  42
  43     // Return conservative estimate of total number of blocks, 0 if unknown
  44     int GetTotalBlocksEstimate();
  45
  46     // Returns last CBlockIndex* in mapBlockIndex that is a checkpoint
  47     CBlockIndex* GetLastCheckpoint(const std::map<uint256, CBlockIndex*>& mapBlockIndex);
  48
  49     // Returns last checkpoint timestamp
  50     unsigned int GetLastCheckpointTime();
  51
  52     extern uint256 hashSyncCheckpoint;
  53     extern CSyncCheckpoint checkpointMessage;
  54     extern uint256 hashInvalidCheckpoint;
  55     extern CCriticalSection cs_hashSyncCheckpoint;
  56
  57     CBlockIndex* GetLastSyncCheckpoint();
  58     bool WriteSyncCheckpoint(const uint256& hashCheckpoint);
  59     bool AcceptPendingSyncCheckpoint();
  60     uint256 AutoSelectSyncCheckpoint();
  61     bool CheckSync(const uint256& hashBlock, const CBlockIndex* pindexPrev);
  62     bool WantedByPendingSyncCheckpoint(uint256 hashBlock);
  63     bool ResetSyncCheckpoint();
  64     void AskForPendingSyncCheckpoint(CNode* pfrom);
  65     bool SetCheckpointPrivKey(std::string strPrivKey);
  66     bool SendSyncCheckpoint(uint256 hashCheckpoint);
  67     bool IsMatureSyncCheckpoint();
  68 }
  69
  70 // ppcoin: synchronized checkpoint
  71 class CUnsignedSyncCheckpoint
  72 {
  73 public:
  74     int nVersion;
  75     uint256 hashCheckpoint;      // checkpoint block
  76
  77     IMPLEMENT_SERIALIZE
  78     (
  79         READWRITE(this->nVersion);
  80         nVersion = this->nVersion;
  81         READWRITE(hashCheckpoint);
  82     )
  83
  84     void SetNull()
  85     {
  86         nVersion = 1;
  87         hashCheckpoint = 0;
  88     }
  89
  90     std::string ToString() const
  91     {
  92         return strprintf(
  93                 "CSyncCheckpoint(\n"
  94                 "    nVersion       = %d\n"
  95                 "    hashCheckpoint = %s\n"
  96                 ")\n",
  97             nVersion,
  98             hashCheckpoint.ToString().c_str());
  99     }
 100
 101     void print() const
 102     {
 103         printf("%s", ToString().c_str());
 104     }
 105 };
 106
 107 class CSyncCheckpoint : public CUnsignedSyncCheckpoint
 108 {
 109 public:
 110     static const std::string strMasterPubKey;
 111     static std::string strMasterPrivKey;
 112
 113     std::vector<unsigned char> vchMsg;
 114     std::vector<unsigned char> vchSig;
 115
 116     CSyncCheckpoint()
 117     {
 118         SetNull();
 119     }
 120
 121     IMPLEMENT_SERIALIZE
 122     (
 123         READWRITE(vchMsg);
 124         READWRITE(vchSig);
 125     )
 126
 127     void SetNull()
 128     {
 129         CUnsignedSyncCheckpoint::SetNull();
 130         vchMsg.clear();
 131         vchSig.clear();
 132     }
 133
 134     bool IsNull() const
 135     {
 136         return (hashCheckpoint == 0);
 137     }
 138
 139     uint256 GetHash() const
 140     {
 141         return SerializeHash(*this);
 142     }
 143
 144     bool RelayTo(CNode* pnode) const
 145     {
 146         // returns true if wasn't already sent
 147         if (pnode->hashCheckpointKnown != hashCheckpoint)
 148         {
 149             pnode->hashCheckpointKnown = hashCheckpoint;
 150             pnode->PushMessage("checkpoint", *this);
 151             return true;
 152         }
 153         return false;
 154     }
 155
 156     bool CheckSignature();
 157     bool ProcessSyncCheckpoint(CNode* pfrom);
 158 };
 159
 160 #endif