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>
9 #include "checkpoints.h"
11 #include "txdb-leveldb.h"
17 typedef std::map<int, std::pair<uint256, unsigned int> > MapCheckpoints;
18 typedef std::list<uint256> ListBannedBlocks;
21 // What makes a good checkpoint block?
22 // + Is surrounded by blocks with reasonable timestamps
23 // (no blocks before with a timestamp after, none after with
25 // + Contains no strange transactions
27 static MapCheckpoints mapCheckpoints =
28 boost::assign::map_list_of
29 ( 0, std::make_pair(hashGenesisBlock, 1360105017) )
30 ( 13560, std::make_pair(uint256("0xa1591a0fcbf11f282d671581edb9f0aadcd06fee69761081e0a3245914c13729"), 1364674052) )
31 ( 143990, std::make_pair(uint256("0x00000000001ff5c3940a9f73ad4a990f64955179bde0f743c76dbf0031429efc"), 1418953493) )
32 ( 149000, std::make_pair(uint256("0x7a24acfcadcf43054e7f7d9f273522c0dfc5791ba4006e0273e7521a8d36c525"), 1420872125) )
33 ( 160000, std::make_pair(uint256("0x000000000001cb1133043d38d077c0e93f66c8b2566779f10f182137d1e34a68"), 1425150237) )
34 ( 200000, std::make_pair(uint256("0x0000000000029f8bbf66e6ea6f3e5db55009404aae0fe395a53dd33142b2bff2"), 1441127233) )
35 ( 221047, std::make_pair(uint256("0xa28aef712e7aa0c285bfe29351ca21ed416689139e3063ef770fc826a8b9e9da"), 1449431646) )
36 ( 243100, std::make_pair(uint256("0x000000000006522d1ebc0734cb0e6b83f5d4da0c3cbc72bd91b82016f611c4f0"), 1458215793) )
37 ( 532000, std::make_pair(uint256("0x0000000000018b7eba5e189c41605780c8a855f74144fa837fa05fa4c67b6ba9"), 1569359486) )
38 ( 561108, std::make_pair(uint256("0x2f3cf523ae1022300b4f40073e506d15ef0d6e208f123aed5b93016f81a10e1e"), 1580943827) )
39 ( 712891, std::make_pair(uint256("0xaaafebcb23c1b8ab49f7517b7a34bcc420cc6f284d9ffc672c1f47b5af2b0088"), 1640557462) )
42 static ListBannedBlocks listBanned =
43 boost::assign::list_of
44 // Invalid block #221047 with future timestamp of 2016/02/23 09:24:17 UTC
45 ( uint256("0x46223e5432ceffe650d5729b4bb8479dcdf0ca1e534fa8e69382dc87b42ea94b") )
48 // TestNet has no checkpoints
49 static MapCheckpoints mapCheckpointsTestnet =
50 boost::assign::map_list_of
51 ( 0, std::make_pair(hashGenesisBlockTestNet, 1360105017) )
54 bool CheckHardened(int nHeight, const uint256& hash)
56 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
58 MapCheckpoints::const_iterator i = checkpoints.find(nHeight);
59 if (i == checkpoints.end()) return true;
60 return hash == i->second.first;
63 bool CheckBanned(const uint256 &nHash)
65 if (fTestNet) // Testnet has no banned blocks
67 ListBannedBlocks::const_iterator it = std::find(listBanned.begin(), listBanned.end(), nHash);
68 return it == listBanned.end();
71 int GetTotalBlocksEstimate()
73 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
75 return checkpoints.rbegin()->first;
78 unsigned int GetLastCheckpointTime()
80 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
82 return checkpoints.rbegin()->second.second;
85 CBlockIndex* GetLastCheckpoint(const std::map<uint256, CBlockIndex*>& mapBlockIndex)
87 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
89 BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, checkpoints)
91 const uint256& hash = i.second.first;
92 std::map<uint256, CBlockIndex*>::const_iterator t = mapBlockIndex.find(hash);
93 if (t != mapBlockIndex.end())
99 // ppcoin: synchronized checkpoint (centrally broadcasted)
100 uint256 hashSyncCheckpoint = 0;
101 uint256 hashPendingCheckpoint = 0;
102 CSyncCheckpoint checkpointMessage;
103 CSyncCheckpoint checkpointMessagePending;
104 uint256 hashInvalidCheckpoint = 0;
105 CCriticalSection cs_hashSyncCheckpoint;
107 // ppcoin: get last synchronized checkpoint
108 CBlockIndex* GetLastSyncCheckpoint()
110 LOCK(cs_hashSyncCheckpoint);
111 if (!mapBlockIndex.count(hashSyncCheckpoint))
112 error("GetSyncCheckpoint: block index missing for current sync-checkpoint %s", hashSyncCheckpoint.ToString().c_str());
114 return mapBlockIndex[hashSyncCheckpoint];
118 // ppcoin: only descendant of current sync-checkpoint is allowed
119 bool ValidateSyncCheckpoint(uint256 hashCheckpoint)
121 if (!mapBlockIndex.count(hashSyncCheckpoint))
122 return error("ValidateSyncCheckpoint: block index missing for current sync-checkpoint %s", hashSyncCheckpoint.ToString().c_str());
123 if (!mapBlockIndex.count(hashCheckpoint))
124 return error("ValidateSyncCheckpoint: block index missing for received sync-checkpoint %s", hashCheckpoint.ToString().c_str());
126 CBlockIndex* pindexSyncCheckpoint = mapBlockIndex[hashSyncCheckpoint];
127 CBlockIndex* pindexCheckpointRecv = mapBlockIndex[hashCheckpoint];
129 if (pindexCheckpointRecv->nHeight <= pindexSyncCheckpoint->nHeight)
131 // Received an older checkpoint, trace back from current checkpoint
132 // to the same height of the received checkpoint to verify
133 // that current checkpoint should be a descendant block
134 CBlockIndex* pindex = pindexSyncCheckpoint;
135 while (pindex->nHeight > pindexCheckpointRecv->nHeight)
136 if ((pindex = pindex->pprev) == NULL)
137 return error("ValidateSyncCheckpoint: pprev null - block index structure failure");
138 if (pindex->GetBlockHash() != hashCheckpoint)
140 hashInvalidCheckpoint = hashCheckpoint;
141 return error("ValidateSyncCheckpoint: new sync-checkpoint %s is conflicting with current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
143 return false; // ignore older checkpoint
146 // Received checkpoint should be a descendant block of the current
147 // checkpoint. Trace back to the same height of current checkpoint
149 CBlockIndex* pindex = pindexCheckpointRecv;
150 while (pindex->nHeight > pindexSyncCheckpoint->nHeight)
151 if ((pindex = pindex->pprev) == NULL)
152 return error("ValidateSyncCheckpoint: pprev2 null - block index structure failure");
153 if (pindex->GetBlockHash() != hashSyncCheckpoint)
155 hashInvalidCheckpoint = hashCheckpoint;
156 return error("ValidateSyncCheckpoint: new sync-checkpoint %s is not a descendant of current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
161 bool WriteSyncCheckpoint(const uint256& hashCheckpoint)
165 if (!txdb.WriteSyncCheckpoint(hashCheckpoint))
168 return error("WriteSyncCheckpoint(): failed to write to db sync checkpoint %s", hashCheckpoint.ToString().c_str());
170 if (!txdb.TxnCommit())
171 return error("WriteSyncCheckpoint(): failed to commit to db sync checkpoint %s", hashCheckpoint.ToString().c_str());
173 Checkpoints::hashSyncCheckpoint = hashCheckpoint;
177 bool AcceptPendingSyncCheckpoint()
179 LOCK(cs_hashSyncCheckpoint);
180 if (hashPendingCheckpoint != 0 && mapBlockIndex.count(hashPendingCheckpoint))
182 if (!ValidateSyncCheckpoint(hashPendingCheckpoint))
184 hashPendingCheckpoint = 0;
185 checkpointMessagePending.SetNull();
190 CBlockIndex* pindexCheckpoint = mapBlockIndex[hashPendingCheckpoint];
191 if (!pindexCheckpoint->IsInMainChain())
194 if (!block.ReadFromDisk(pindexCheckpoint))
195 return error("AcceptPendingSyncCheckpoint: ReadFromDisk failed for sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
196 if (!block.SetBestChain(txdb, pindexCheckpoint))
198 hashInvalidCheckpoint = hashPendingCheckpoint;
199 return error("AcceptPendingSyncCheckpoint: SetBestChain failed for sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
203 if (!WriteSyncCheckpoint(hashPendingCheckpoint))
204 return error("AcceptPendingSyncCheckpoint(): failed to write sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
205 hashPendingCheckpoint = 0;
206 checkpointMessage = checkpointMessagePending;
207 checkpointMessagePending.SetNull();
208 printf("AcceptPendingSyncCheckpoint : sync-checkpoint at %s\n", hashSyncCheckpoint.ToString().c_str());
209 // relay the checkpoint
210 if (!checkpointMessage.IsNull())
212 for (std::vector<CNode*>::iterator it = vNodes.begin(); it != vNodes.end(); ++it)
213 checkpointMessage.RelayTo(*it);
220 // Automatically select a suitable sync-checkpoint
221 uint256 AutoSelectSyncCheckpoint()
223 const CBlockIndex *pindex = pindexBest;
224 // Search backward for a block within max span and maturity window
225 while (pindex->pprev && (pindex->GetBlockTime() + CHECKPOINT_MAX_SPAN > pindexBest->GetBlockTime() || pindex->nHeight + 8 > pindexBest->nHeight))
226 pindex = pindex->pprev;
227 return pindex->GetBlockHash();
230 // Check against synchronized checkpoint
231 bool CheckSync(const uint256& hashBlock, const CBlockIndex* pindexPrev)
233 if (fTestNet) return true; // Testnet has no checkpoints
234 int nHeight = pindexPrev->nHeight + 1;
236 LOCK(cs_hashSyncCheckpoint);
237 // sync-checkpoint should always be accepted block
238 assert(mapBlockIndex.count(hashSyncCheckpoint));
239 const CBlockIndex* pindexSync = mapBlockIndex[hashSyncCheckpoint];
241 if (nHeight > pindexSync->nHeight)
243 // trace back to same height as sync-checkpoint
244 const CBlockIndex* pindex = pindexPrev;
245 while (pindex->nHeight > pindexSync->nHeight)
246 if ((pindex = pindex->pprev) == NULL)
247 return error("CheckSync: pprev null - block index structure failure");
248 if (pindex->nHeight < pindexSync->nHeight || pindex->GetBlockHash() != hashSyncCheckpoint)
249 return false; // only descendant of sync-checkpoint can pass check
251 if (nHeight == pindexSync->nHeight && hashBlock != hashSyncCheckpoint)
252 return false; // same height with sync-checkpoint
253 if (nHeight < pindexSync->nHeight && !mapBlockIndex.count(hashBlock))
254 return false; // lower height than sync-checkpoint
258 bool WantedByPendingSyncCheckpoint(uint256 hashBlock)
260 LOCK(cs_hashSyncCheckpoint);
261 if (hashPendingCheckpoint == 0)
263 if (hashBlock == hashPendingCheckpoint)
265 if (mapOrphanBlocks.count(hashPendingCheckpoint)
266 && hashBlock == WantedByOrphan(mapOrphanBlocks[hashPendingCheckpoint]))
271 // ppcoin: reset synchronized checkpoint to last hardened checkpoint
272 bool ResetSyncCheckpoint()
274 LOCK(cs_hashSyncCheckpoint);
275 const uint256& hash = mapCheckpoints.rbegin()->second.first;
276 if (mapBlockIndex.count(hash) && !mapBlockIndex[hash]->IsInMainChain())
278 // checkpoint block accepted but not yet in main chain
279 printf("ResetSyncCheckpoint: SetBestChain to hardened checkpoint %s\n", hash.ToString().c_str());
282 if (!block.ReadFromDisk(mapBlockIndex[hash]))
283 return error("ResetSyncCheckpoint: ReadFromDisk failed for hardened checkpoint %s", hash.ToString().c_str());
284 if (!block.SetBestChain(txdb, mapBlockIndex[hash]))
286 return error("ResetSyncCheckpoint: SetBestChain failed for hardened checkpoint %s", hash.ToString().c_str());
289 else if(!mapBlockIndex.count(hash))
291 // checkpoint block not yet accepted
292 hashPendingCheckpoint = hash;
293 checkpointMessagePending.SetNull();
294 printf("ResetSyncCheckpoint: pending for sync-checkpoint %s\n", hashPendingCheckpoint.ToString().c_str());
297 BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, mapCheckpoints)
299 const uint256& hash = i.second.first;
300 if (mapBlockIndex.count(hash) && mapBlockIndex[hash]->IsInMainChain())
302 if (!WriteSyncCheckpoint(hash))
303 return error("ResetSyncCheckpoint: failed to write sync checkpoint %s", hash.ToString().c_str());
304 printf("ResetSyncCheckpoint: sync-checkpoint reset to %s\n", hashSyncCheckpoint.ToString().c_str());
312 void AskForPendingSyncCheckpoint(CNode* pfrom)
314 LOCK(cs_hashSyncCheckpoint);
315 if (pfrom && hashPendingCheckpoint != 0 && (!mapBlockIndex.count(hashPendingCheckpoint)) && (!mapOrphanBlocks.count(hashPendingCheckpoint)))
316 pfrom->AskFor(CInv(MSG_BLOCK, hashPendingCheckpoint));
319 bool SetCheckpointPrivKey(std::string strPrivKey)
321 // Test signing a sync-checkpoint with genesis block
322 CSyncCheckpoint checkpoint;
323 checkpoint.hashCheckpoint = !fTestNet ? hashGenesisBlock : hashGenesisBlockTestNet;
324 CDataStream sMsg(SER_NETWORK, PROTOCOL_VERSION);
325 sMsg << (CUnsignedSyncCheckpoint)checkpoint;
326 checkpoint.vchMsg = std::vector<unsigned char>(sMsg.begin(), sMsg.end());
328 std::vector<unsigned char> vchPrivKey = ParseHex(strPrivKey);
330 key.SetPrivKey(CPrivKey(vchPrivKey.begin(), vchPrivKey.end())); // if key is not correct openssl may crash
331 if (!key.Sign(Hash(checkpoint.vchMsg.begin(), checkpoint.vchMsg.end()), checkpoint.vchSig))
334 // Test signing successful, proceed
335 CSyncCheckpoint::strMasterPrivKey = strPrivKey;
339 bool SendSyncCheckpoint(uint256 hashCheckpoint)
341 CSyncCheckpoint checkpoint;
342 checkpoint.hashCheckpoint = hashCheckpoint;
343 CDataStream sMsg(SER_NETWORK, PROTOCOL_VERSION);
344 sMsg << (CUnsignedSyncCheckpoint)checkpoint;
345 checkpoint.vchMsg = std::vector<unsigned char>(sMsg.begin(), sMsg.end());
347 if (CSyncCheckpoint::strMasterPrivKey.empty())
348 return error("SendSyncCheckpoint: Checkpoint master key unavailable.");
349 std::vector<unsigned char> vchPrivKey = ParseHex(CSyncCheckpoint::strMasterPrivKey);
351 key.SetPrivKey(CPrivKey(vchPrivKey.begin(), vchPrivKey.end())); // if key is not correct openssl may crash
352 if (!key.Sign(Hash(checkpoint.vchMsg.begin(), checkpoint.vchMsg.end()), checkpoint.vchSig))
353 return error("SendSyncCheckpoint: Unable to sign checkpoint, check private key?");
355 if(!checkpoint.ProcessSyncCheckpoint(NULL))
357 printf("WARNING: SendSyncCheckpoint: Failed to process checkpoint.\n");
364 for (std::vector<CNode*>::iterator it = vNodes.begin(); it != vNodes.end(); ++it)
365 checkpoint.RelayTo(*it);
370 // Is the sync-checkpoint outside maturity window?
371 bool IsMatureSyncCheckpoint()
373 LOCK(cs_hashSyncCheckpoint);
374 // sync-checkpoint should always be accepted block
375 assert(mapBlockIndex.count(hashSyncCheckpoint));
376 const CBlockIndex* pindexSync = mapBlockIndex[hashSyncCheckpoint];
377 return (nBestHeight >= pindexSync->nHeight + nCoinbaseMaturity ||
378 pindexSync->GetBlockTime() + nStakeMinAge < GetAdjustedTime());
382 // ppcoin: sync-checkpoint master key
383 const std::string CSyncCheckpoint::strMasterPubKey = "04a51b735f816de4ec3f891d5b38bbc91e1f7245c7c08d17990760b86b4d8fc3910a850ffecf73bfa8886f01739a0c4c4322201282d07b6e48ce931cc92af94850";
385 std::string CSyncCheckpoint::strMasterPrivKey = "";
387 // ppcoin: verify signature of sync-checkpoint message
388 bool CSyncCheckpoint::CheckSignature()
390 CPubKey key(ParseHex(CSyncCheckpoint::strMasterPubKey));
391 if (!key.Verify(Hash(vchMsg.begin(), vchMsg.end()), vchSig))
392 return error("CSyncCheckpoint::CheckSignature() : verify signature failed");
394 // Now unserialize the data
395 CDataStream sMsg(vchMsg, SER_NETWORK, PROTOCOL_VERSION);
396 sMsg >> *(CUnsignedSyncCheckpoint*)this;
400 // process synchronized checkpoint
401 bool CSyncCheckpoint::ProcessSyncCheckpoint(CNode* pfrom)
403 if (!CheckSignature())
406 LOCK(Checkpoints::cs_hashSyncCheckpoint);
407 if (!mapBlockIndex.count(hashCheckpoint))
409 // We haven't received the checkpoint chain, keep the checkpoint as pending
410 Checkpoints::hashPendingCheckpoint = hashCheckpoint;
411 Checkpoints::checkpointMessagePending = *this;
412 printf("ProcessSyncCheckpoint: pending for sync-checkpoint %s\n", hashCheckpoint.ToString().c_str());
413 // Ask this guy to fill in what we're missing
416 pfrom->PushGetBlocks(pindexBest, hashCheckpoint);
417 // ask directly as well in case rejected earlier by duplicate
418 // proof-of-stake because getblocks may not get it this time
419 pfrom->AskFor(CInv(MSG_BLOCK, mapOrphanBlocks.count(hashCheckpoint)? WantedByOrphan(mapOrphanBlocks[hashCheckpoint]) : hashCheckpoint));
424 if (!Checkpoints::ValidateSyncCheckpoint(hashCheckpoint))
428 CBlockIndex* pindexCheckpoint = mapBlockIndex[hashCheckpoint];
429 if (!pindexCheckpoint->IsInMainChain())
431 // checkpoint chain received but not yet main chain
433 if (!block.ReadFromDisk(pindexCheckpoint))
434 return error("ProcessSyncCheckpoint: ReadFromDisk failed for sync checkpoint %s", hashCheckpoint.ToString().c_str());
435 if (!block.SetBestChain(txdb, pindexCheckpoint))
437 Checkpoints::hashInvalidCheckpoint = hashCheckpoint;
438 return error("ProcessSyncCheckpoint: SetBestChain failed for sync checkpoint %s", hashCheckpoint.ToString().c_str());
442 if (!Checkpoints::WriteSyncCheckpoint(hashCheckpoint))
443 return error("ProcessSyncCheckpoint(): failed to write sync checkpoint %s", hashCheckpoint.ToString().c_str());
444 Checkpoints::checkpointMessage = *this;
445 Checkpoints::hashPendingCheckpoint = 0;
446 Checkpoints::checkpointMessagePending.SetNull();
447 printf("ProcessSyncCheckpoint: sync-checkpoint at %s\n", hashCheckpoint.ToString().c_str());