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 }
  48
  49 // ppcoin: synchronized checkpoint
  50 class CUnsignedSyncCheckpoint
  51 {
  52 public:
  53     int nVersion;
  54     uint256 hashCheckpoint;      // checkpoint block
  55
  56     IMPLEMENT_SERIALIZE
  57     (
  58         READWRITE(this->nVersion);
  59         nVersion = this->nVersion;
  60         READWRITE(hashCheckpoint);
  61     )
  62
  63     void SetNull()
  64     {
  65         nVersion = 1;
  66         hashCheckpoint = 0;
  67     }
  68
  69     std::string ToString() const
  70     {
  71         return strprintf(
  72                 "CSyncCheckpoint(\n"
  73                 "    nVersion       = %d\n"
  74                 "    hashCheckpoint = %s\n"
  75                 ")\n",
  76             nVersion,
  77             hashCheckpoint.ToString().c_str());
  78     }
  79
  80     void print() const
  81     {
  82         printf("%s", ToString().c_str());
  83     }
  84 };
  85
  86 class CSyncCheckpoint : public CUnsignedSyncCheckpoint
  87 {
  88 public:
  89     static const std::string strMasterPubKey;
  90
  91     std::vector<unsigned char> vchMsg;
  92     std::vector<unsigned char> vchSig;
  93
  94     CSyncCheckpoint()
  95     {
  96         SetNull();
  97     }
  98
  99     IMPLEMENT_SERIALIZE
 100     (
 101         READWRITE(vchMsg);
 102         READWRITE(vchSig);
 103     )
 104
 105     void SetNull()
 106     {
 107         CUnsignedSyncCheckpoint::SetNull();
 108         vchMsg.clear();
 109         vchSig.clear();
 110     }
 111
 112     bool IsNull() const
 113     {
 114         return (hashCheckpoint == 0);
 115     }
 116
 117     uint256 GetHash() const
 118     {
 119         return SerializeHash(*this);
 120     }
 121
 122     bool RelayTo(CNode* pnode) const
 123     {
 124         // returns true if wasn't already sent
 125         if (pnode->hashCheckpointKnown != hashCheckpoint)
 126         {
 127             pnode->hashCheckpointKnown = hashCheckpoint;
 128             pnode->PushMessage("checkpoint", *this);
 129             return true;
 130         }
 131         return false;
 132     }
 133
 134     bool CheckSignature();
 135     bool ProcessSyncCheckpoint(CNode* pfrom);
 136 };
 137
 138 #endif