// Copyright (c) 2011 The Bitcoin developers
-// Copyright (c) 2011 The PPCoin developers
+// Copyright (c) 2011-2012 The PPCoin developers
// Distributed under the MIT/X11 software license, see the accompanying
// file license.txt or http://www.opensource.org/licenses/mit-license.php.
( 0, hashGenesisBlock )
; // ppcoin: no checkpoint yet; to be created in future releases
- // ppcoin: automatic checkpoint (represented by height of checkpoint)
- int nAutoCheckpoint = 0;
-
bool CheckHardened(int nHeight, const uint256& hash)
{
if (fTestNet) return true; // Testnet has no checkpoints
return hash == i->second;
}
+ int GetTotalBlocksEstimate()
+ {
+ if (fTestNet) return 0;
+
+ return mapCheckpoints.rbegin()->first;
+ }
+
+ CBlockIndex* GetLastCheckpoint(const std::map<uint256, CBlockIndex*>& mapBlockIndex)
+ {
+ if (fTestNet) return NULL;
+
+ int64 nResult;
+ BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, mapCheckpoints)
+ {
+ const uint256& hash = i.second;
+ std::map<uint256, CBlockIndex*>::const_iterator t = mapBlockIndex.find(hash);
+ if (t != mapBlockIndex.end())
+ return t->second;
+ }
+ return NULL;
+ }
+
+ // ppcoin: synchronized checkpoint (centrally broadcasted)
+ uint256 hashSyncCheckpoint;
+ CSyncCheckpoint checkpointMessage;
+ CSyncCheckpoint checkpointMessagePending;
+ uint256 hashInvalidCheckpoint = 0;
+ CCriticalSection cs_hashSyncCheckpoint;
+
+ // ppcoin: only descendant of current sync-checkpoint is allowed
+ bool ValidateSyncCheckpoint(uint256 hashCheckpoint)
+ {
+ if (!mapBlockIndex.count(hashSyncCheckpoint))
+ return error("ValidateSyncCheckpoint: block index missing for current sync-checkpoint %s", hashSyncCheckpoint.ToString().c_str());
+ if (!mapBlockIndex.count(hashCheckpoint))
+ return error("ValidateSyncCheckpoint: block index missing for received sync-checkpoint %s", hashCheckpoint.ToString().c_str());
+
+ CBlockIndex* pindexSyncCheckpoint = mapBlockIndex[hashSyncCheckpoint];
+ CBlockIndex* pindexCheckpointRecv = mapBlockIndex[hashCheckpoint];
+
+ if (pindexCheckpointRecv->nHeight <= pindexSyncCheckpoint->nHeight)
+ {
+ // Received an older checkpoint, trace back from current checkpoint
+ // to the same height of the received checkpoint to verify
+ // that current checkpoint should be a descendant block
+ CBlockIndex* pindex = pindexSyncCheckpoint;
+ while (pindex->nHeight > pindexCheckpointRecv->nHeight)
+ if (!(pindex = pindex->pprev))
+ return error("ValidateSyncCheckpoint: pprev1 null - block index structure failure");
+ if (pindex->GetBlockHash() != hashCheckpoint)
+ {
+ hashInvalidCheckpoint = hashCheckpoint;
+ return error("ValidateSyncCheckpoint: new sync-checkpoint %s is conflicting with current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
+ }
+ return false; // ignore older checkpoint
+ }
+
+ // Received checkpoint should be a descendant block of the current
+ // checkpoint. Trace back to the same height of current checkpoint
+ // to verify.
+ CBlockIndex* pindex = pindexCheckpointRecv;
+ while (pindex->nHeight > pindexSyncCheckpoint->nHeight)
+ if (!(pindex = pindex->pprev))
+ return error("ValidateSyncCheckpoint: pprev2 null - block index structure failure");
+ if (pindex->GetBlockHash() != hashSyncCheckpoint)
+ {
+ hashInvalidCheckpoint = hashCheckpoint;
+ return error("ValidateSyncCheckpoint: new sync-checkpoint %s is not a descendant of current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
+ }
+ return true;
+ }
+
+ bool AcceptPendingSyncCheckpoint()
+ {
+ CRITICAL_BLOCK(cs_hashSyncCheckpoint)
+ {
+ if ((!checkpointMessagePending.IsNull()) && mapBlockIndex.count(checkpointMessagePending.hashCheckpoint))
+ {
+ if (!ValidateSyncCheckpoint(checkpointMessagePending.hashCheckpoint))
+ {
+ checkpointMessagePending.SetNull();
+ return false;
+ }
+
+ CTxDB txdb;
+ CBlockIndex* pindexCheckpoint = mapBlockIndex[checkpointMessagePending.hashCheckpoint];
+ if (!pindexCheckpoint->IsInMainChain())
+ {
+ txdb.TxnBegin();
+ if (!Reorganize(txdb, pindexCheckpoint))
+ {
+ txdb.TxnAbort();
+ hashInvalidCheckpoint = checkpointMessagePending.hashCheckpoint;
+ return error("ProcessSyncCheckpoint: Reorganize failed for sync checkpoint %s", checkpointMessagePending.hashCheckpoint.ToString().c_str());
+ }
+ }
+
+ txdb.TxnBegin();
+ if (!txdb.WriteSyncCheckpoint(checkpointMessagePending.hashCheckpoint))
+ {
+ txdb.TxnAbort();
+ return error("AcceptPendingSyncCheckpoint() : failed to write to db sync checkpoint %s\n", checkpointMessagePending.hashCheckpoint.ToString().c_str());
+ }
+ if (!txdb.TxnCommit())
+ return error("AcceptPendingSyncCheckpoint() : failed to commit to db sync checkpoint %s\n", checkpointMessagePending.hashCheckpoint.ToString().c_str());
+ txdb.Close();
+
+ hashSyncCheckpoint = checkpointMessagePending.hashCheckpoint;
+ checkpointMessage = checkpointMessagePending;
+ checkpointMessagePending.SetNull();
+ printf("AcceptPendingSyncCheckpoint : sync-checkpoint at %s\n", hashSyncCheckpoint.ToString().c_str());
+ // relay the checkpoint
+ CRITICAL_BLOCK(cs_hashSyncCheckpoint)
+ BOOST_FOREACH(CNode* pnode, vNodes)
+ checkpointMessage.RelayTo(pnode);
+ return true;
+ }
+ }
+
+ return false;
+ }
+
+ uint256 AutoSelectSyncCheckpoint()
+ {
+ // select block roughly 8 hours ago
+ CBlockIndex *pindex = mapBlockIndex[hashSyncCheckpoint];
+ while (pindex->pnext && pindex->pnext->GetBlockTime() + AUTO_CHECKPOINT_MIN_SPAN <= GetAdjustedTime())
+ pindex = pindex->pnext;
+ return pindex->GetBlockHash();
+ }
+
+ // Check against synchronized checkpoint
+ bool CheckSync(const uint256& hashBlock, const CBlockIndex* pindexPrev)
+ {
+ if (fTestNet) return true; // Testnet has no checkpoints
+ int nHeight = pindexPrev->nHeight + 1;
+
+ CRITICAL_BLOCK(cs_hashSyncCheckpoint)
+ {
+ // sync-checkpoint should always be accepted block
+ assert(mapBlockIndex.count(hashSyncCheckpoint));
+ const CBlockIndex* pindexSync = mapBlockIndex[hashSyncCheckpoint];
+
+ if (nHeight > pindexSync->nHeight)
+ {
+ // trace back to same height as sync-checkpoint
+ const CBlockIndex* pindex = pindexPrev;
+ while (pindex->nHeight > pindexSync->nHeight)
+ if (!(pindex = pindex->pprev))
+ return error("CheckSync: pprev null - block index structure failure");
+ if (pindex->nHeight < pindexSync->nHeight || pindex->GetBlockHash() != hashSyncCheckpoint)
+ return false; // only descendant of sync-checkpoint can pass check
+ }
+ if (nHeight == pindexSync->nHeight && hashBlock != hashSyncCheckpoint)
+ return false; // same height with sync-checkpoint
+ if (nHeight < pindexSync->nHeight && !mapBlockIndex.count(hashBlock))
+ return false; // lower height than sync-checkpoint
+ }
+ return true;
+ }
+
+ bool IsPendingSyncCheckpoint(uint256 hashBlock)
+ {
+ CRITICAL_BLOCK(cs_hashSyncCheckpoint)
+ return ((!checkpointMessagePending.IsNull()) && hashBlock == checkpointMessagePending.hashCheckpoint);
+ }
+
+ // ppcoin: automatic checkpoint (represented by height of checkpoint)
+ int nAutoCheckpoint = 0;
+ int nBranchPoint = 0; // branch point to alternative branch
+
// ppcoin: check automatic checkpoint
// To pass the check:
// - All ancestors (including the block itself) have block index already
if (pindex->nHeight >= nAutoCheckpoint)
return true;
else
+ {
+ nBranchPoint = pindex->nHeight;
return error("Checkpoints: new block on alternative branch at height=%d before auto checkpoint at height=%d", pindex->nHeight, nAutoCheckpoint);
+ }
}
else
pindex = pindex->pprev;
return error("Checkpoints: failed to find any ancestor on main chain for the new block - internal error");
}
- // ppcoin: get next auto checkpoint in the chain
+ // ppcoin: get next chain checkpoint
int GetNextChainCheckpoint(const CBlockIndex *pindexLast)
{
CBigNum bnTarget;
CBigNum bnTargetMax = 0; // max target of all blocks since checkpoint
CBigNum bnTargetMin = 0; // min target of all candidate checkpoints
- int nMinTargetHeight = 0; // min target height since checkpoint
+ int nMinTargetHeight = 0; // min target height of candidate checkpoints
int nCheckpointMin = 0; // minimum candidate checkpoint
int nCheckpointMax = 0; // maximum candidate checkpoint
int nDepth = pindexLast->nHeight - pindexLast->nCheckpoint;
if (bnTargetMin * 100 > bnTargetMax * 90)
return nCheckpointMax;
if (bnTarget * 100 > bnTargetMax * 90)
- return std::min(nCheckpointMax, nMinTargetHeight);
+ return nMinTargetHeight;
else
return nCheckpointMin;
}
+ // ppcoin: get next auto checkpoint from the new chain checkpoint
+ int GetNextAutoCheckpoint(int nCheckpoint)
+ {
+ return (std::max(nAutoCheckpoint, nCheckpoint));
+ }
+
// ppcoin: advance to next automatic checkpoint
void AdvanceAutoCheckpoint(int nCheckpoint)
{
- nAutoCheckpoint = std::max(nAutoCheckpoint, nCheckpoint);
+ nAutoCheckpoint = GetNextAutoCheckpoint(nCheckpoint);
printf("Checkpoints: auto checkpoint now at height=%d\n", nAutoCheckpoint);
}
- int GetTotalBlocksEstimate()
+ // ppcoin: reset auto checkpoint
+ bool ResetAutoCheckpoint(int nCheckpoint)
{
- if (fTestNet) return 0;
+ if (nCheckpoint <= 0 || nCheckpoint > nBestHeight)
+ return error("ResetAutoCheckpoint() : new checkpoint invalid");
+ if (nCheckpoint >= nAutoCheckpoint)
+ return error("ResetAutoCheckpoint() : new checkpoint not earlier than current auto checkpoint");
+ CTxDB txdb;
+ txdb.TxnBegin();
+ if (!txdb.WriteAutoCheckpoint(nCheckpoint, true))
+ return error("ResetAutoCheckpoint() : database write failed");
+ if (!txdb.TxnCommit())
+ return error("ResetAutoCheckpoint() : database commit failed");
+ nAutoCheckpoint = nCheckpoint;
+ nBranchPoint = 0; // clear branch point
- return mapCheckpoints.rbegin()->first;
+ // clear ban list to accept alternative branches
+ CRITICAL_BLOCK(cs_vNodes)
+ {
+ BOOST_FOREACH(CNode* pnode, vNodes)
+ pnode->ClearBanned();
+ }
+
+ return true;
}
+}
- CBlockIndex* GetLastCheckpoint(const std::map<uint256, CBlockIndex*>& mapBlockIndex)
+// ppcoin: process synchronized checkpoint
+bool CSyncCheckpoint::ProcessSyncCheckpoint(CNode* pfrom)
+{
+ if (!CheckSignature())
+ return false;
+
+ CRITICAL_BLOCK(Checkpoints::cs_hashSyncCheckpoint)
{
- if (fTestNet) return NULL;
+ if (!mapBlockIndex.count(hashCheckpoint))
+ {
+ // We haven't received the checkpoint chain, keep the checkpoint as pending
+ Checkpoints::checkpointMessagePending = *this;
+ printf("ProcessSyncCheckpoint: pending for sync-checkpoint %s\n", hashCheckpoint.ToString().c_str());
+ // Ask this guy to fill in what we're missing
+ if (pfrom)
+ {
+ pfrom->PushGetBlocks(pindexBest, hashCheckpoint);
+ // ask directly as well in case rejected earlier by duplicate
+ // proof-of-stake because getblocks may not get it this time
+ pfrom->AskFor(CInv(MSG_BLOCK, mapOrphanBlocks.count(hashCheckpoint)? GetOrphanRoot(mapOrphanBlocks[hashCheckpoint]) : hashCheckpoint));
+ }
+ return false;
+ }
- int64 nResult;
- BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, mapCheckpoints)
+ if (!Checkpoints::ValidateSyncCheckpoint(hashCheckpoint))
+ return false;
+
+ CTxDB txdb;
+ CBlockIndex* pindexCheckpoint = mapBlockIndex[hashCheckpoint];
+ if (!pindexCheckpoint->IsInMainChain())
{
- const uint256& hash = i.second;
- std::map<uint256, CBlockIndex*>::const_iterator t = mapBlockIndex.find(hash);
- if (t != mapBlockIndex.end())
- return t->second;
+ // checkpoint chain received but not yet main chain
+ txdb.TxnBegin();
+ if (!Reorganize(txdb, pindexCheckpoint))
+ {
+ txdb.TxnAbort();
+ Checkpoints::hashInvalidCheckpoint = hashCheckpoint;
+ return error("ProcessSyncCheckpoint: Reorganize failed for sync checkpoint %s", hashCheckpoint.ToString().c_str());
+ }
}
- return NULL;
+
+ txdb.TxnBegin();
+ if (!txdb.WriteSyncCheckpoint(hashCheckpoint))
+ {
+ txdb.TxnAbort();
+ return error("ProcessSyncCheckpoint(): failed to write to db sync checkpoint %s", hashCheckpoint.ToString().c_str());
+ }
+ if (!txdb.TxnCommit())
+ return error("ProcessSyncCheckpoint(): failed to commit to db sync checkpoint %s", hashCheckpoint.ToString().c_str());
+ txdb.Close();
+
+ Checkpoints::hashSyncCheckpoint = hashCheckpoint;
+ Checkpoints::checkpointMessage = *this;
+ Checkpoints::checkpointMessagePending.SetNull();
+ printf("ProcessSyncCheckpoint: sync-checkpoint at %s\n", hashCheckpoint.ToString().c_str());
}
+ return true;
}
git://git.novaco.in / novacoin.git / blobdiff