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 AcceptPendingSyncCheckpoint();
  42     uint256 AutoSelectSyncCheckpoint();
  43     bool CheckSync(const uint256& hashBlock, const CBlockIndex* pindexPrev);
  44     bool WantedByPendingSyncCheckpoint(uint256 hashBlock);
  45 }
  46
  47 // ppcoin: synchronized checkpoint
  48 class CUnsignedSyncCheckpoint
  49 {
  50 public:
  51     int nVersion;
  52     uint256 hashCheckpoint;      // checkpoint block
  53
  54     IMPLEMENT_SERIALIZE
  55     (
  56         READWRITE(this->nVersion);
  57         nVersion = this->nVersion;
  58         READWRITE(hashCheckpoint);
  59     )
  60
  61     void SetNull()
  62     {
  63         nVersion = 1;
  64         hashCheckpoint = 0;
  65     }
  66
  67     std::string ToString() const
  68     {
  69         return strprintf(
  70                 "CSyncCheckpoint(\n"
  71                 "    nVersion       = %d\n"
  72                 "    hashCheckpoint = %s\n"
  73                 ")\n",
  74             nVersion,
  75             hashCheckpoint.ToString().c_str());
  76     }
  77
  78     void print() const
  79     {
  80         printf("%s", ToString().c_str());
  81     }
  82 };
  83
  84 class CSyncCheckpoint : public CUnsignedSyncCheckpoint
  85 {
  86 public:
  87     static const std::string strMasterPubKey;
  88
  89     std::vector<unsigned char> vchMsg;
  90     std::vector<unsigned char> vchSig;
  91
  92     CSyncCheckpoint()
  93     {
  94         SetNull();
  95     }
  96
  97     IMPLEMENT_SERIALIZE
  98     (
  99         READWRITE(vchMsg);
 100         READWRITE(vchSig);
 101     )
 102
 103     void SetNull()
 104     {
 105         CUnsignedSyncCheckpoint::SetNull();
 106         vchMsg.clear();
 107         vchSig.clear();
 108     }
 109
 110     bool IsNull() const
 111     {
 112         return (hashCheckpoint == 0);
 113     }
 114
 115     uint256 GetHash() const
 116     {
 117         return SerializeHash(*this);
 118     }
 119
 120     bool RelayTo(CNode* pnode) const
 121     {
 122         // returns true if wasn't already sent
 123         if (pnode->hashCheckpointKnown != hashCheckpoint)
 124         {
 125             pnode->hashCheckpointKnown = hashCheckpoint;
 126             pnode->PushMessage("checkpoint", *this);
 127             return true;
 128         }
 129         return false;
 130     }
 131
 132     bool CheckSignature();
 133     bool ProcessSyncCheckpoint(CNode* pfrom);
 134 };
 135
 136 #endif