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