1 // Copyright (c) 2009-2012 The Bitcoin developers
2 // Distributed under the MIT/X11 software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
5 #include <boost/assign/list_of.hpp> // for 'map_list_of()'
6 #include <boost/foreach.hpp>
8 #include "checkpoints.h"
16 typedef std::map<int, std::pair<uint256, unsigned int> > MapCheckpoints;
19 // What makes a good checkpoint block?
20 // + Is surrounded by blocks with reasonable timestamps
21 // (no blocks before with a timestamp after, none after with
23 // + Contains no strange transactions
25 static MapCheckpoints mapCheckpoints =
26 boost::assign::map_list_of
27 ( 0, std::make_pair(hashGenesisBlock, 1360105017) )
28 ( 9690, std::make_pair(uint256("0x00000000026561450859c46868099e0df6068a538f038cb18988fd8d47dcdaf5"), 1362791423) )
29 ( 13560, std::make_pair(uint256("0xa1591a0fcbf11f282d671581edb9f0aadcd06fee69761081e0a3245914c13729"), 1364674052) )
30 ( 37092, std::make_pair(uint256("0x0000000000a38c2f98556f46793b453e92d8fab2d31c0b93fd08bcf78e56099d"), 1376677203) )
31 ( 44200, std::make_pair(uint256("0xc9bda7232a18b9c1f5ff974a9e5566b2d1879ceb8fc0e9e61fba9038a25b8447"), 1380145962) )
32 ( 65000, std::make_pair(uint256("0xfb2b51a2fd65062c98a7a6053cde46aeaefebb95ba2f680e85a29ee25b1dcf05"), 1388526385) )
33 ( 68600, std::make_pair(uint256("0xb646b0562080ab9411f85d4b2a1ca8b197c67ae170c5e328406871b44233cb06"), 1389867276) )
34 ( 92161, std::make_pair(uint256("0x000000000079090eb31e7fa55487e4e666466253e68b213f44b7977ea7a2eeec"), 1398919969) )
35 ( 98661, std::make_pair(uint256("0x48328dfc0eaffc659723739c6202854d1624449340193bdea3e71ece4ccdd43f"), 1401469019) )
38 // TestNet has no checkpoints
39 static MapCheckpoints mapCheckpointsTestnet =
40 boost::assign::map_list_of
41 ( 0, std::make_pair(hashGenesisBlockTestNet, 1360105017) )
44 bool CheckHardened(int nHeight, const uint256& hash)
46 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
48 MapCheckpoints::const_iterator i = checkpoints.find(nHeight);
49 if (i == checkpoints.end()) return true;
50 return hash == i->second.first;
53 int GetTotalBlocksEstimate()
55 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
57 return checkpoints.rbegin()->first;
60 int GetLastCheckpointTime()
62 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
64 return checkpoints.rbegin()->second.second;
67 CBlockIndex* GetLastCheckpoint(const std::map<uint256, CBlockIndex*>& mapBlockIndex)
69 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
71 BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, checkpoints)
73 const uint256& hash = i.second.first;
74 std::map<uint256, CBlockIndex*>::const_iterator t = mapBlockIndex.find(hash);
75 if (t != mapBlockIndex.end())
81 // ppcoin: synchronized checkpoint (centrally broadcasted)
82 uint256 hashSyncCheckpoint = 0;
83 uint256 hashPendingCheckpoint = 0;
84 CSyncCheckpoint checkpointMessage;
85 CSyncCheckpoint checkpointMessagePending;
86 uint256 hashInvalidCheckpoint = 0;
87 CCriticalSection cs_hashSyncCheckpoint;
89 // ppcoin: get last synchronized checkpoint
90 CBlockIndex* GetLastSyncCheckpoint()
92 LOCK(cs_hashSyncCheckpoint);
93 if (!mapBlockIndex.count(hashSyncCheckpoint))
94 error("GetSyncCheckpoint: block index missing for current sync-checkpoint %s", hashSyncCheckpoint.ToString().c_str());
96 return mapBlockIndex[hashSyncCheckpoint];
100 // ppcoin: only descendant of current sync-checkpoint is allowed
101 bool ValidateSyncCheckpoint(uint256 hashCheckpoint)
103 if (!mapBlockIndex.count(hashSyncCheckpoint))
104 return error("ValidateSyncCheckpoint: block index missing for current sync-checkpoint %s", hashSyncCheckpoint.ToString().c_str());
105 if (!mapBlockIndex.count(hashCheckpoint))
106 return error("ValidateSyncCheckpoint: block index missing for received sync-checkpoint %s", hashCheckpoint.ToString().c_str());
108 CBlockIndex* pindexSyncCheckpoint = mapBlockIndex[hashSyncCheckpoint];
109 CBlockIndex* pindexCheckpointRecv = mapBlockIndex[hashCheckpoint];
111 if (pindexCheckpointRecv->nHeight <= pindexSyncCheckpoint->nHeight)
113 // Received an older checkpoint, trace back from current checkpoint
114 // to the same height of the received checkpoint to verify
115 // that current checkpoint should be a descendant block
116 CBlockIndex* pindex = pindexSyncCheckpoint;
117 while (pindex->nHeight > pindexCheckpointRecv->nHeight)
118 if (!(pindex = pindex->pprev))
119 return error("ValidateSyncCheckpoint: pprev null - block index structure failure");
120 if (pindex->GetBlockHash() != hashCheckpoint)
122 hashInvalidCheckpoint = hashCheckpoint;
123 return error("ValidateSyncCheckpoint: new sync-checkpoint %s is conflicting with current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
125 return false; // ignore older checkpoint
128 // Received checkpoint should be a descendant block of the current
129 // checkpoint. Trace back to the same height of current checkpoint
131 CBlockIndex* pindex = pindexCheckpointRecv;
132 while (pindex->nHeight > pindexSyncCheckpoint->nHeight)
133 if (!(pindex = pindex->pprev))
134 return error("ValidateSyncCheckpoint: pprev2 null - block index structure failure");
135 if (pindex->GetBlockHash() != hashSyncCheckpoint)
137 hashInvalidCheckpoint = hashCheckpoint;
138 return error("ValidateSyncCheckpoint: new sync-checkpoint %s is not a descendant of current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
143 bool WriteSyncCheckpoint(const uint256& hashCheckpoint)
147 if (!txdb.WriteSyncCheckpoint(hashCheckpoint))
150 return error("WriteSyncCheckpoint(): failed to write to db sync checkpoint %s", hashCheckpoint.ToString().c_str());
152 if (!txdb.TxnCommit())
153 return error("WriteSyncCheckpoint(): failed to commit to db sync checkpoint %s", hashCheckpoint.ToString().c_str());
155 Checkpoints::hashSyncCheckpoint = hashCheckpoint;
159 bool AcceptPendingSyncCheckpoint()
161 LOCK(cs_hashSyncCheckpoint);
162 if (hashPendingCheckpoint != 0 && mapBlockIndex.count(hashPendingCheckpoint))
164 if (!ValidateSyncCheckpoint(hashPendingCheckpoint))
166 hashPendingCheckpoint = 0;
167 checkpointMessagePending.SetNull();
172 CBlockIndex* pindexCheckpoint = mapBlockIndex[hashPendingCheckpoint];
173 if (!pindexCheckpoint->IsInMainChain())
176 if (!block.ReadFromDisk(pindexCheckpoint))
177 return error("AcceptPendingSyncCheckpoint: ReadFromDisk failed for sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
178 if (!block.SetBestChain(txdb, pindexCheckpoint))
180 hashInvalidCheckpoint = hashPendingCheckpoint;
181 return error("AcceptPendingSyncCheckpoint: SetBestChain failed for sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
185 if (!WriteSyncCheckpoint(hashPendingCheckpoint))
186 return error("AcceptPendingSyncCheckpoint(): failed to write sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
187 hashPendingCheckpoint = 0;
188 checkpointMessage = checkpointMessagePending;
189 checkpointMessagePending.SetNull();
190 printf("AcceptPendingSyncCheckpoint : sync-checkpoint at %s\n", hashSyncCheckpoint.ToString().c_str());
191 // relay the checkpoint
192 if (!checkpointMessage.IsNull())
194 BOOST_FOREACH(CNode* pnode, vNodes)
195 checkpointMessage.RelayTo(pnode);
202 // Automatically select a suitable sync-checkpoint
203 uint256 AutoSelectSyncCheckpoint()
205 const CBlockIndex *pindex = pindexBest;
206 // Search backward for a block within max span and maturity window
207 while (pindex->pprev && (pindex->GetBlockTime() + CHECKPOINT_MAX_SPAN > pindexBest->GetBlockTime() || pindex->nHeight + 8 > pindexBest->nHeight))
208 pindex = pindex->pprev;
209 return pindex->GetBlockHash();
212 // Check against synchronized checkpoint
213 bool CheckSync(const uint256& hashBlock, const CBlockIndex* pindexPrev)
215 if (fTestNet) return true; // Testnet has no checkpoints
216 int nHeight = pindexPrev->nHeight + 1;
218 LOCK(cs_hashSyncCheckpoint);
219 // sync-checkpoint should always be accepted block
220 assert(mapBlockIndex.count(hashSyncCheckpoint));
221 const CBlockIndex* pindexSync = mapBlockIndex[hashSyncCheckpoint];
223 if (nHeight > pindexSync->nHeight)
225 // trace back to same height as sync-checkpoint
226 const CBlockIndex* pindex = pindexPrev;
227 while (pindex->nHeight > pindexSync->nHeight)
228 if (!(pindex = pindex->pprev))
229 return error("CheckSync: pprev null - block index structure failure");
230 if (pindex->nHeight < pindexSync->nHeight || pindex->GetBlockHash() != hashSyncCheckpoint)
231 return false; // only descendant of sync-checkpoint can pass check
233 if (nHeight == pindexSync->nHeight && hashBlock != hashSyncCheckpoint)
234 return false; // same height with sync-checkpoint
235 if (nHeight < pindexSync->nHeight && !mapBlockIndex.count(hashBlock))
236 return false; // lower height than sync-checkpoint
240 bool WantedByPendingSyncCheckpoint(uint256 hashBlock)
242 LOCK(cs_hashSyncCheckpoint);
243 if (hashPendingCheckpoint == 0)
245 if (hashBlock == hashPendingCheckpoint)
247 if (mapOrphanBlocks.count(hashPendingCheckpoint)
248 && hashBlock == WantedByOrphan(mapOrphanBlocks[hashPendingCheckpoint]))
253 // ppcoin: reset synchronized checkpoint to last hardened checkpoint
254 bool ResetSyncCheckpoint()
256 LOCK(cs_hashSyncCheckpoint);
257 const uint256& hash = mapCheckpoints.rbegin()->second.first;
258 if (mapBlockIndex.count(hash) && !mapBlockIndex[hash]->IsInMainChain())
260 // checkpoint block accepted but not yet in main chain
261 printf("ResetSyncCheckpoint: SetBestChain to hardened checkpoint %s\n", hash.ToString().c_str());
264 if (!block.ReadFromDisk(mapBlockIndex[hash]))
265 return error("ResetSyncCheckpoint: ReadFromDisk failed for hardened checkpoint %s", hash.ToString().c_str());
266 if (!block.SetBestChain(txdb, mapBlockIndex[hash]))
268 return error("ResetSyncCheckpoint: SetBestChain failed for hardened checkpoint %s", hash.ToString().c_str());
271 else if(!mapBlockIndex.count(hash))
273 // checkpoint block not yet accepted
274 hashPendingCheckpoint = hash;
275 checkpointMessagePending.SetNull();
276 printf("ResetSyncCheckpoint: pending for sync-checkpoint %s\n", hashPendingCheckpoint.ToString().c_str());
279 BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, mapCheckpoints)
281 const uint256& hash = i.second.first;
282 if (mapBlockIndex.count(hash) && mapBlockIndex[hash]->IsInMainChain())
284 if (!WriteSyncCheckpoint(hash))
285 return error("ResetSyncCheckpoint: failed to write sync checkpoint %s", hash.ToString().c_str());
286 printf("ResetSyncCheckpoint: sync-checkpoint reset to %s\n", hashSyncCheckpoint.ToString().c_str());
294 void AskForPendingSyncCheckpoint(CNode* pfrom)
296 LOCK(cs_hashSyncCheckpoint);
297 if (pfrom && hashPendingCheckpoint != 0 && (!mapBlockIndex.count(hashPendingCheckpoint)) && (!mapOrphanBlocks.count(hashPendingCheckpoint)))
298 pfrom->AskFor(CInv(MSG_BLOCK, hashPendingCheckpoint));
301 bool SetCheckpointPrivKey(std::string strPrivKey)
303 // Test signing a sync-checkpoint with genesis block
304 CSyncCheckpoint checkpoint;
305 checkpoint.hashCheckpoint = !fTestNet ? hashGenesisBlock : hashGenesisBlockTestNet;
306 CDataStream sMsg(SER_NETWORK, PROTOCOL_VERSION);
307 sMsg << (CUnsignedSyncCheckpoint)checkpoint;
308 checkpoint.vchMsg = std::vector<unsigned char>(sMsg.begin(), sMsg.end());
310 std::vector<unsigned char> vchPrivKey = ParseHex(strPrivKey);
312 key.SetPrivKey(CPrivKey(vchPrivKey.begin(), vchPrivKey.end())); // if key is not correct openssl may crash
313 if (!key.Sign(Hash(checkpoint.vchMsg.begin(), checkpoint.vchMsg.end()), checkpoint.vchSig))
316 // Test signing successful, proceed
317 CSyncCheckpoint::strMasterPrivKey = strPrivKey;
321 bool SendSyncCheckpoint(uint256 hashCheckpoint)
323 CSyncCheckpoint checkpoint;
324 checkpoint.hashCheckpoint = hashCheckpoint;
325 CDataStream sMsg(SER_NETWORK, PROTOCOL_VERSION);
326 sMsg << (CUnsignedSyncCheckpoint)checkpoint;
327 checkpoint.vchMsg = std::vector<unsigned char>(sMsg.begin(), sMsg.end());
329 if (CSyncCheckpoint::strMasterPrivKey.empty())
330 return error("SendSyncCheckpoint: Checkpoint master key unavailable.");
331 std::vector<unsigned char> vchPrivKey = ParseHex(CSyncCheckpoint::strMasterPrivKey);
333 key.SetPrivKey(CPrivKey(vchPrivKey.begin(), vchPrivKey.end())); // if key is not correct openssl may crash
334 if (!key.Sign(Hash(checkpoint.vchMsg.begin(), checkpoint.vchMsg.end()), checkpoint.vchSig))
335 return error("SendSyncCheckpoint: Unable to sign checkpoint, check private key?");
337 if(!checkpoint.ProcessSyncCheckpoint(NULL))
339 printf("WARNING: SendSyncCheckpoint: Failed to process checkpoint.\n");
346 BOOST_FOREACH(CNode* pnode, vNodes)
347 checkpoint.RelayTo(pnode);
352 // Is the sync-checkpoint outside maturity window?
353 bool IsMatureSyncCheckpoint()
355 LOCK(cs_hashSyncCheckpoint);
356 // sync-checkpoint should always be accepted block
357 assert(mapBlockIndex.count(hashSyncCheckpoint));
358 const CBlockIndex* pindexSync = mapBlockIndex[hashSyncCheckpoint];
359 return (nBestHeight >= pindexSync->nHeight + nCoinbaseMaturity ||
360 pindexSync->GetBlockTime() + nStakeMinAge < GetAdjustedTime());
364 // ppcoin: sync-checkpoint master key
365 const std::string CSyncCheckpoint::strMasterPubKey = "04a51b735f816de4ec3f891d5b38bbc91e1f7245c7c08d17990760b86b4d8fc3910a850ffecf73bfa8886f01739a0c4c4322201282d07b6e48ce931cc92af94850";
367 std::string CSyncCheckpoint::strMasterPrivKey = "";
369 // ppcoin: verify signature of sync-checkpoint message
370 bool CSyncCheckpoint::CheckSignature()
373 if (!key.SetPubKey(ParseHex(CSyncCheckpoint::strMasterPubKey)))
374 return error("CSyncCheckpoint::CheckSignature() : SetPubKey failed");
375 if (!key.Verify(Hash(vchMsg.begin(), vchMsg.end()), vchSig))
376 return error("CSyncCheckpoint::CheckSignature() : verify signature failed");
378 // Now unserialize the data
379 CDataStream sMsg(vchMsg, SER_NETWORK, PROTOCOL_VERSION);
380 sMsg >> *(CUnsignedSyncCheckpoint*)this;
384 // ppcoin: process synchronized checkpoint
385 bool CSyncCheckpoint::ProcessSyncCheckpoint(CNode* pfrom)
387 if (!CheckSignature())
390 LOCK(Checkpoints::cs_hashSyncCheckpoint);
391 if (!mapBlockIndex.count(hashCheckpoint))
393 // We haven't received the checkpoint chain, keep the checkpoint as pending
394 Checkpoints::hashPendingCheckpoint = hashCheckpoint;
395 Checkpoints::checkpointMessagePending = *this;
396 printf("ProcessSyncCheckpoint: pending for sync-checkpoint %s\n", hashCheckpoint.ToString().c_str());
397 // Ask this guy to fill in what we're missing
400 pfrom->PushGetBlocks(pindexBest, hashCheckpoint);
401 // ask directly as well in case rejected earlier by duplicate
402 // proof-of-stake because getblocks may not get it this time
403 pfrom->AskFor(CInv(MSG_BLOCK, mapOrphanBlocks.count(hashCheckpoint)? WantedByOrphan(mapOrphanBlocks[hashCheckpoint]) : hashCheckpoint));
408 if (!Checkpoints::ValidateSyncCheckpoint(hashCheckpoint))
412 CBlockIndex* pindexCheckpoint = mapBlockIndex[hashCheckpoint];
413 if (!pindexCheckpoint->IsInMainChain())
415 // checkpoint chain received but not yet main chain
417 if (!block.ReadFromDisk(pindexCheckpoint))
418 return error("ProcessSyncCheckpoint: ReadFromDisk failed for sync checkpoint %s", hashCheckpoint.ToString().c_str());
419 if (!block.SetBestChain(txdb, pindexCheckpoint))
421 Checkpoints::hashInvalidCheckpoint = hashCheckpoint;
422 return error("ProcessSyncCheckpoint: SetBestChain failed for sync checkpoint %s", hashCheckpoint.ToString().c_str());
426 if (!Checkpoints::WriteSyncCheckpoint(hashCheckpoint))
427 return error("ProcessSyncCheckpoint(): failed to write sync checkpoint %s", hashCheckpoint.ToString().c_str());
428 Checkpoints::checkpointMessage = *this;
429 Checkpoints::hashPendingCheckpoint = 0;
430 Checkpoints::checkpointMessagePending.SetNull();
431 printf("ProcessSyncCheckpoint: sync-checkpoint at %s\n", hashCheckpoint.ToString().c_str());