List of unconditionally banned blocks.
[novacoin.git] / src / checkpoints.cpp
index c690b26..095def3 100644 (file)
@@ -4,16 +4,18 @@
 
 #include <boost/assign/list_of.hpp> // for 'map_list_of()'
 #include <boost/foreach.hpp>
+#include <algorithm>
 
 #include "checkpoints.h"
 
-#include "db.h"
+#include "txdb.h"
 #include "main.h"
 #include "uint256.h"
 
 namespace Checkpoints
 {
-    typedef std::map<int, uint256> MapCheckpoints;
+    typedef std::map<int, std::pair<uint256, unsigned int> > MapCheckpoints;
+    typedef std::list<uint256> ListBannedBlocks;
 
     //
     // What makes a good checkpoint block?
@@ -24,18 +26,25 @@ namespace Checkpoints
     //
     static MapCheckpoints mapCheckpoints =
         boost::assign::map_list_of
-        ( 0, hashGenesisBlock )
-        ( 6000, uint256("0x000000000945e3c9d8e15df834e802521eb79f9ceb4191a27bdfadad4b777f4a"))
-        ( 9690, uint256("0x00000000026561450859c46868099e0df6068a538f038cb18988fd8d47dcdaf5"))
-        ( 13560, uint256("0xa1591a0fcbf11f282d671581edb9f0aadcd06fee69761081e0a3245914c13729"))
-        ( 14189, uint256("0x00000000020f76474d2522b19c7bfafc43ba6ecbabae54293bcd9546159c8c1d"))
-        ( 19600, uint256("0x252ae08d6df4bc7220c1dcdaed7b8a6e78bab05a60173511e8f565a3a38ce3c3"))
-        ( 21800, uint256("0x64bdeb35023f240ed01beaa082f840f2d4cc6defccbbcda1260de87e58296b37"))
-        ;
-
+        ( 0,     std::make_pair(hashGenesisBlock, 1360105017) )
+        ( 13560, std::make_pair(uint256("0xa1591a0fcbf11f282d671581edb9f0aadcd06fee69761081e0a3245914c13729"), 1364674052) )
+        ( 143990, std::make_pair(uint256("0x00000000001ff5c3940a9f73ad4a990f64955179bde0f743c76dbf0031429efc"), 1418953493) )
+        ( 149000, std::make_pair(uint256("0x7a24acfcadcf43054e7f7d9f273522c0dfc5791ba4006e0273e7521a8d36c525"), 1420872125) )
+        ( 160000, std::make_pair(uint256("0x000000000001cb1133043d38d077c0e93f66c8b2566779f10f182137d1e34a68"), 1425150237) )
+        ( 200000, std::make_pair(uint256("0x0000000000029f8bbf66e6ea6f3e5db55009404aae0fe395a53dd33142b2bff2"), 1441127233) )
+        ( 221047, std::make_pair(uint256("0xa28aef712e7aa0c285bfe29351ca21ed416689139e3063ef770fc826a8b9e9da"), 1449431646) )
+    ;
+    
+    static ListBannedBlocks listBanned =
+        boost::assign::list_of
+        // Invalid block #221047 with future timestamp of 2016/02/23 09:24:17 UTC
+        ( uint256("0x46223e5432ceffe650d5729b4bb8479dcdf0ca1e534fa8e69382dc87b42ea94b") )
+    ;
+
+    // TestNet has no checkpoints
     static MapCheckpoints mapCheckpointsTestnet =
         boost::assign::map_list_of
-        ( 0, hashGenesisBlockTestNet )
+        ( 0, std::make_pair(hashGenesisBlockTestNet, 1360105017) )
         ;
 
     bool CheckHardened(int nHeight, const uint256& hash)
@@ -44,7 +53,15 @@ namespace Checkpoints
 
         MapCheckpoints::const_iterator i = checkpoints.find(nHeight);
         if (i == checkpoints.end()) return true;
-        return hash == i->second;
+        return hash == i->second.first;
+    }
+
+    bool CheckBanned(const uint256 &nHash)
+    {
+        if (fTestNet) // Testnet has no banned blocks
+            return true;
+        ListBannedBlocks::const_iterator it = std::find(listBanned.begin(), listBanned.end(), nHash);
+        return it == listBanned.end();
     }
 
     int GetTotalBlocksEstimate()
@@ -54,13 +71,20 @@ namespace Checkpoints
         return checkpoints.rbegin()->first;
     }
 
+    unsigned int GetLastCheckpointTime()
+    {
+        MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
+
+        return checkpoints.rbegin()->second.second;
+    }
+
     CBlockIndex* GetLastCheckpoint(const std::map<uint256, CBlockIndex*>& mapBlockIndex)
     {
         MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
 
         BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, checkpoints)
         {
-            const uint256& hash = i.second;
+            const uint256& hash = i.second.first;
             std::map<uint256, CBlockIndex*>::const_iterator t = mapBlockIndex.find(hash);
             if (t != mapBlockIndex.end())
                 return t->second;
@@ -106,7 +130,7 @@ namespace Checkpoints
             CBlockIndex* pindex = pindexSyncCheckpoint;
             while (pindex->nHeight > pindexCheckpointRecv->nHeight)
                 if (!(pindex = pindex->pprev))
-                    return error("ValidateSyncCheckpoint: pprev1 null - block index structure failure");
+                    return error("ValidateSyncCheckpoint: pprev null - block index structure failure");
             if (pindex->GetBlockHash() != hashCheckpoint)
             {
                 hashInvalidCheckpoint = hashCheckpoint;
@@ -141,7 +165,10 @@ namespace Checkpoints
         }
         if (!txdb.TxnCommit())
             return error("WriteSyncCheckpoint(): failed to commit to db sync checkpoint %s", hashCheckpoint.ToString().c_str());
+
+#ifndef USE_LEVELDB
         txdb.Close();
+#endif
 
         Checkpoints::hashSyncCheckpoint = hashCheckpoint;
         return true;
@@ -172,8 +199,10 @@ namespace Checkpoints
                     return error("AcceptPendingSyncCheckpoint: SetBestChain failed for sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
                 }
             }
-            txdb.Close();
 
+#ifndef USE_LEVELDB
+            txdb.Close();
+#endif
             if (!WriteSyncCheckpoint(hashPendingCheckpoint))
                 return error("AcceptPendingSyncCheckpoint(): failed to write sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
             hashPendingCheckpoint = 0;
@@ -194,14 +223,10 @@ namespace Checkpoints
     // Automatically select a suitable sync-checkpoint 
     uint256 AutoSelectSyncCheckpoint()
     {
-        // Proof-of-work blocks are immediately checkpointed
-        // to defend against 51% attack which rejects other miners block 
-
-        // Select the last proof-of-work block
-        const CBlockIndex *pindex = GetLastBlockIndex(pindexBest, false);
-        // Search forward for a block within max span and maturity window
-        while (pindex->pnext && (pindex->GetBlockTime() + CHECKPOINT_MAX_SPAN <= pindexBest->GetBlockTime() || pindex->nHeight + std::min(6, nCoinbaseMaturity - 20) <= pindexBest->nHeight))
-            pindex = pindex->pnext;
+        const CBlockIndex *pindex = pindexBest;
+        // Search backward for a block within max span and maturity window
+        while (pindex->pprev && (pindex->GetBlockTime() + CHECKPOINT_MAX_SPAN > pindexBest->GetBlockTime() || pindex->nHeight + 8 > pindexBest->nHeight))
+            pindex = pindex->pprev;
         return pindex->GetBlockHash();
     }
 
@@ -250,7 +275,7 @@ namespace Checkpoints
     bool ResetSyncCheckpoint()
     {
         LOCK(cs_hashSyncCheckpoint);
-        const uint256& hash = mapCheckpoints.rbegin()->second;
+        const uint256& hash = mapCheckpoints.rbegin()->second.first;
         if (mapBlockIndex.count(hash) && !mapBlockIndex[hash]->IsInMainChain())
         {
             // checkpoint block accepted but not yet in main chain
@@ -263,7 +288,11 @@ namespace Checkpoints
             {
                 return error("ResetSyncCheckpoint: SetBestChain failed for hardened checkpoint %s", hash.ToString().c_str());
             }
+
+#ifndef USE_LEVELDB
             txdb.Close();
+#endif
+
         }
         else if(!mapBlockIndex.count(hash))
         {
@@ -275,7 +304,7 @@ namespace Checkpoints
 
         BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, mapCheckpoints)
         {
-            const uint256& hash = i.second;
+            const uint256& hash = i.second.first;
             if (mapBlockIndex.count(hash) && mapBlockIndex[hash]->IsInMainChain())
             {
                 if (!WriteSyncCheckpoint(hash))
@@ -356,16 +385,6 @@ namespace Checkpoints
         return (nBestHeight >= pindexSync->nHeight + nCoinbaseMaturity ||
                 pindexSync->GetBlockTime() + nStakeMinAge < GetAdjustedTime());
     }
-
-    // Is the sync-checkpoint too old?
-    bool IsSyncCheckpointTooOld(unsigned int nSeconds)
-    {
-        LOCK(cs_hashSyncCheckpoint);
-        // sync-checkpoint should always be accepted block
-        assert(mapBlockIndex.count(hashSyncCheckpoint));
-        const CBlockIndex* pindexSync = mapBlockIndex[hashSyncCheckpoint];
-        return (pindexSync->GetBlockTime() + nSeconds < GetAdjustedTime());
-    }
 }
 
 // ppcoin: sync-checkpoint master key
@@ -388,7 +407,7 @@ bool CSyncCheckpoint::CheckSignature()
     return true;
 }
 
-// ppcoin: process synchronized checkpoint
+// process synchronized checkpoint
 bool CSyncCheckpoint::ProcessSyncCheckpoint(CNode* pfrom)
 {
     if (!CheckSignature())
@@ -429,7 +448,10 @@ bool CSyncCheckpoint::ProcessSyncCheckpoint(CNode* pfrom)
             return error("ProcessSyncCheckpoint: SetBestChain failed for sync checkpoint %s", hashCheckpoint.ToString().c_str());
         }
     }
+
+#ifndef USE_LEVELDB
     txdb.Close();
+#endif
 
     if (!Checkpoints::WriteSyncCheckpoint(hashCheckpoint))
         return error("ProcessSyncCheckpoint(): failed to write sync checkpoint %s", hashCheckpoint.ToString().c_str());