New syncronized checkpoints policy: no immediate PoW block checkpointing.

[novacoin.git] / src / checkpoints.cpp

diff --git a/src/checkpoints.cpp b/src/checkpoints.cpp
index 2439d04..a64243a 100644 (file)
--- a/src/checkpoints.cpp
+++ b/src/checkpoints.cpp
@@ -43,6 +43,8 @@ namespace Checkpoints
         ( 9690, initCheckpoint(uint256("0x00000000026561450859c46868099e0df6068a538f038cb18988fd8d47dcdaf5"), 1362791423) )
         ( 13560, initCheckpoint(uint256("0xa1591a0fcbf11f282d671581edb9f0aadcd06fee69761081e0a3245914c13729"), 1364674052) )
         ( 37092, initCheckpoint(uint256("0x0000000000a38c2f98556f46793b453e92d8fab2d31c0b93fd08bcf78e56099d"), 1376677203) )
+        ( 44200, initCheckpoint(uint256("0xc9bda7232a18b9c1f5ff974a9e5566b2d1879ceb8fc0e9e61fba9038a25b8447"), 1380145962) )
+        ( 65000, initCheckpoint(uint256("0xfb2b51a2fd65062c98a7a6053cde46aeaefebb95ba2f680e85a29ee25b1dcf05"), 1388526385) )
     ;
 
     // TestNet has no checkpoints
@@ -126,7 +128,7 @@ 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;
@@ -219,14 +221,10 @@ 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();
     }