src/checkpoints.h

   1 // Copyright (c) 2011 The Bitcoin developers
   2 // Copyright (c) 2011-2012 The PPCoin developers
   3 // Distributed under the MIT/X11 software license, see the accompanying
   4 // file license.txt or http://www.opensource.org/licenses/mit-license.php.
   5 #ifndef BITCOIN_CHECKPOINT_H
   6 #define  BITCOIN_CHECKPOINT_H
   7
   8 #include <map>
   9 #include "util.h"
  10
  11 // ppcoin: auto checkpoint min at 8 hours; max at 16 hours
  12 #define AUTO_CHECKPOINT_MIN_SPAN   (60 * 60 * 8)
  13 #define AUTO_CHECKPOINT_MAX_SPAN   (60 * 60 * 16)
  14 #define AUTO_CHECKPOINT_TRUST_SPAN (60 * 60 * 24)
  15
  16 class uint256;
  17 class CBlockIndex;
  18 class CSyncCheckpoint;
  19
  20 //
  21 // Block-chain checkpoints are compiled-in sanity checks.
  22 // They are updated every release or three.
  23 //
  24 namespace Checkpoints
  25 {
  26     // Returns true if block passes checkpoint checks
  27     bool CheckHardened(int nHeight, const uint256& hash);
  28
  29     // Return conservative estimate of total number of blocks, 0 if unknown
  30     int GetTotalBlocksEstimate();
  31
  32     // Returns last CBlockIndex* in mapBlockIndex that is a checkpoint
  33     CBlockIndex* GetLastCheckpoint(const std::map<uint256, CBlockIndex*>& mapBlockIndex);
  34
  35     extern uint256 hashSyncCheckpoint;
  36     extern CSyncCheckpoint checkpointMessage;
  37     extern uint256 hashInvalidCheckpoint;
  38     extern CCriticalSection cs_hashSyncCheckpoint;
  39
  40     CBlockIndex* GetLastSyncCheckpoint();
  41     bool WriteSyncCheckpoint(const uint256& hashCheckpoint);
  42     bool AcceptPendingSyncCheckpoint();
  43     uint256 AutoSelectSyncCheckpoint();
  44     bool CheckSync(const uint256& hashBlock, const CBlockIndex* pindexPrev);
  45     bool WantedByPendingSyncCheckpoint(uint256 hashBlock);
  46     bool ResetSyncCheckpoint();
  47     void AskForPendingSyncCheckpoint(CNode* pfrom);
  48 }
  49
  50 // ppcoin: synchronized checkpoint
  51 class CUnsignedSyncCheckpoint
  52 {
  53 public:
  54     int nVersion;
  55     uint256 hashCheckpoint;      // checkpoint block
  56
  57     IMPLEMENT_SERIALIZE
  58     (
  59         READWRITE(this->nVersion);
  60         nVersion = this->nVersion;
  61         READWRITE(hashCheckpoint);
  62     )
  63
  64     void SetNull()
  65     {
  66         nVersion = 1;
  67         hashCheckpoint = 0;
  68     }
  69
  70     std::string ToString() const
  71     {
  72         return strprintf(
  73                 "CSyncCheckpoint(\n"
  74                 "    nVersion       = %d\n"
  75                 "    hashCheckpoint = %s\n"
  76                 ")\n",
  77             nVersion,
  78             hashCheckpoint.ToString().c_str());
  79     }
  80
  81     void print() const
  82     {
  83         printf("%s", ToString().c_str());
  84     }
  85 };
  86
  87 class CSyncCheckpoint : public CUnsignedSyncCheckpoint
  88 {
  89 public:
  90     static const std::string strMasterPubKey;
  91
  92     std::vector<unsigned char> vchMsg;
  93     std::vector<unsigned char> vchSig;
  94
  95     CSyncCheckpoint()
  96     {
  97         SetNull();
  98     }
  99
 100     IMPLEMENT_SERIALIZE
 101     (
 102         READWRITE(vchMsg);
 103         READWRITE(vchSig);
 104     )
 105
 106     void SetNull()
 107     {
 108         CUnsignedSyncCheckpoint::SetNull();
 109         vchMsg.clear();
 110         vchSig.clear();
 111     }
 112
 113     bool IsNull() const
 114     {
 115         return (hashCheckpoint == 0);
 116     }
 117
 118     uint256 GetHash() const
 119     {
 120         return SerializeHash(*this);
 121     }
 122
 123     bool RelayTo(CNode* pnode) const
 124     {
 125         // returns true if wasn't already sent
 126         if (pnode->hashCheckpointKnown != hashCheckpoint)
 127         {
 128             pnode->hashCheckpointKnown = hashCheckpoint;
 129             pnode->PushMessage("checkpoint", *this);
 130             return true;
 131         }
 132         return false;
 133     }
 134
 135     bool CheckSignature();
 136     bool ProcessSyncCheckpoint(CNode* pfrom);
 137 };
 138
 139 #endif