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) )
41 static ListBannedBlocks listBanned =
42 boost::assign::list_of
43 // Invalid block #221047 with future timestamp of 2016/02/23 09:24:17 UTC
44 ( uint256("0x46223e5432ceffe650d5729b4bb8479dcdf0ca1e534fa8e69382dc87b42ea94b") )
47 // TestNet has no checkpoints
48 static MapCheckpoints mapCheckpointsTestnet =
49 boost::assign::map_list_of
50 ( 0, std::make_pair(hashGenesisBlockTestNet, 1360105017) )
53 bool CheckHardened(int nHeight, const uint256& hash)
55 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
57 MapCheckpoints::const_iterator i = checkpoints.find(nHeight);
58 if (i == checkpoints.end()) return true;
59 return hash == i->second.first;
62 bool CheckBanned(const uint256 &nHash)
64 if (fTestNet) // Testnet has no banned blocks
66 ListBannedBlocks::const_iterator it = std::find(listBanned.begin(), listBanned.end(), nHash);
67 return it == listBanned.end();
70 int GetTotalBlocksEstimate()
72 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
74 return checkpoints.rbegin()->first;
77 unsigned int GetLastCheckpointTime()
79 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
81 return checkpoints.rbegin()->second.second;
84 CBlockIndex* GetLastCheckpoint(const std::map<uint256, CBlockIndex*>& mapBlockIndex)
86 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
88 BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, checkpoints)
90 const uint256& hash = i.second.first;
91 std::map<uint256, CBlockIndex*>::const_iterator t = mapBlockIndex.find(hash);
92 if (t != mapBlockIndex.end())
98 // ppcoin: synchronized checkpoint (centrally broadcasted)
99 uint256 hashSyncCheckpoint = 0;
100 uint256 hashPendingCheckpoint = 0;
101 CSyncCheckpoint checkpointMessage;
102 CSyncCheckpoint checkpointMessagePending;
103 uint256 hashInvalidCheckpoint = 0;
104 CCriticalSection cs_hashSyncCheckpoint;
106 // ppcoin: get last synchronized checkpoint
107 CBlockIndex* GetLastSyncCheckpoint()
109 LOCK(cs_hashSyncCheckpoint);
110 if (!mapBlockIndex.count(hashSyncCheckpoint))
111 error("GetSyncCheckpoint: block index missing for current sync-checkpoint %s", hashSyncCheckpoint.ToString().c_str());
113 return mapBlockIndex[hashSyncCheckpoint];
117 // ppcoin: only descendant of current sync-checkpoint is allowed
118 bool ValidateSyncCheckpoint(uint256 hashCheckpoint)
120 if (!mapBlockIndex.count(hashSyncCheckpoint))
121 return error("ValidateSyncCheckpoint: block index missing for current sync-checkpoint %s", hashSyncCheckpoint.ToString().c_str());
122 if (!mapBlockIndex.count(hashCheckpoint))
123 return error("ValidateSyncCheckpoint: block index missing for received sync-checkpoint %s", hashCheckpoint.ToString().c_str());
125 CBlockIndex* pindexSyncCheckpoint = mapBlockIndex[hashSyncCheckpoint];
126 CBlockIndex* pindexCheckpointRecv = mapBlockIndex[hashCheckpoint];
128 if (pindexCheckpointRecv->nHeight <= pindexSyncCheckpoint->nHeight)
130 // Received an older checkpoint, trace back from current checkpoint
131 // to the same height of the received checkpoint to verify
132 // that current checkpoint should be a descendant block
133 CBlockIndex* pindex = pindexSyncCheckpoint;
134 while (pindex->nHeight > pindexCheckpointRecv->nHeight)
135 if ((pindex = pindex->pprev) == NULL)
136 return error("ValidateSyncCheckpoint: pprev null - block index structure failure");
137 if (pindex->GetBlockHash() != hashCheckpoint)
139 hashInvalidCheckpoint = hashCheckpoint;
140 return error("ValidateSyncCheckpoint: new sync-checkpoint %s is conflicting with current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
142 return false; // ignore older checkpoint
145 // Received checkpoint should be a descendant block of the current
146 // checkpoint. Trace back to the same height of current checkpoint
148 CBlockIndex* pindex = pindexCheckpointRecv;
149 while (pindex->nHeight > pindexSyncCheckpoint->nHeight)
150 if ((pindex = pindex->pprev) == NULL)
151 return error("ValidateSyncCheckpoint: pprev2 null - block index structure failure");
152 if (pindex->GetBlockHash() != hashSyncCheckpoint)
154 hashInvalidCheckpoint = hashCheckpoint;
155 return error("ValidateSyncCheckpoint: new sync-checkpoint %s is not a descendant of current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
160 bool WriteSyncCheckpoint(const uint256& hashCheckpoint)
164 if (!txdb.WriteSyncCheckpoint(hashCheckpoint))
167 return error("WriteSyncCheckpoint(): failed to write to db sync checkpoint %s", hashCheckpoint.ToString().c_str());
169 if (!txdb.TxnCommit())
170 return error("WriteSyncCheckpoint(): failed to commit to db sync checkpoint %s", hashCheckpoint.ToString().c_str());
172 Checkpoints::hashSyncCheckpoint = hashCheckpoint;
176 bool AcceptPendingSyncCheckpoint()
178 LOCK(cs_hashSyncCheckpoint);
179 if (hashPendingCheckpoint != 0 && mapBlockIndex.count(hashPendingCheckpoint))
181 if (!ValidateSyncCheckpoint(hashPendingCheckpoint))
183 hashPendingCheckpoint = 0;
184 checkpointMessagePending.SetNull();
189 CBlockIndex* pindexCheckpoint = mapBlockIndex[hashPendingCheckpoint];
190 if (!pindexCheckpoint->IsInMainChain())
193 if (!block.ReadFromDisk(pindexCheckpoint))
194 return error("AcceptPendingSyncCheckpoint: ReadFromDisk failed for sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
195 if (!block.SetBestChain(txdb, pindexCheckpoint))
197 hashInvalidCheckpoint = hashPendingCheckpoint;
198 return error("AcceptPendingSyncCheckpoint: SetBestChain failed for sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
202 if (!WriteSyncCheckpoint(hashPendingCheckpoint))
203 return error("AcceptPendingSyncCheckpoint(): failed to write sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
204 hashPendingCheckpoint = 0;
205 checkpointMessage = checkpointMessagePending;
206 checkpointMessagePending.SetNull();
207 printf("AcceptPendingSyncCheckpoint : sync-checkpoint at %s\n", hashSyncCheckpoint.ToString().c_str());
208 // relay the checkpoint
209 if (!checkpointMessage.IsNull())
211 for (std::vector<CNode*>::iterator it = vNodes.begin(); it != vNodes.end(); ++it)
212 checkpointMessage.RelayTo(*it);
219 // Automatically select a suitable sync-checkpoint
220 uint256 AutoSelectSyncCheckpoint()
222 const CBlockIndex *pindex = pindexBest;
223 // Search backward for a block within max span and maturity window
224 while (pindex->pprev && (pindex->GetBlockTime() + CHECKPOINT_MAX_SPAN > pindexBest->GetBlockTime() || pindex->nHeight + 8 > pindexBest->nHeight))
225 pindex = pindex->pprev;
226 return pindex->GetBlockHash();
229 // Check against synchronized checkpoint
230 bool CheckSync(const uint256& hashBlock, const CBlockIndex* pindexPrev)
232 if (fTestNet) return true; // Testnet has no checkpoints
233 int nHeight = pindexPrev->nHeight + 1;
235 LOCK(cs_hashSyncCheckpoint);
236 // sync-checkpoint should always be accepted block
237 assert(mapBlockIndex.count(hashSyncCheckpoint));
238 const CBlockIndex* pindexSync = mapBlockIndex[hashSyncCheckpoint];
240 if (nHeight > pindexSync->nHeight)
242 // trace back to same height as sync-checkpoint
243 const CBlockIndex* pindex = pindexPrev;
244 while (pindex->nHeight > pindexSync->nHeight)
245 if ((pindex = pindex->pprev) == NULL)
246 return error("CheckSync: pprev null - block index structure failure");
247 if (pindex->nHeight < pindexSync->nHeight || pindex->GetBlockHash() != hashSyncCheckpoint)
248 return false; // only descendant of sync-checkpoint can pass check
250 if (nHeight == pindexSync->nHeight && hashBlock != hashSyncCheckpoint)
251 return false; // same height with sync-checkpoint
252 if (nHeight < pindexSync->nHeight && !mapBlockIndex.count(hashBlock))
253 return false; // lower height than sync-checkpoint
257 bool WantedByPendingSyncCheckpoint(uint256 hashBlock)
259 LOCK(cs_hashSyncCheckpoint);
260 if (hashPendingCheckpoint == 0)
262 if (hashBlock == hashPendingCheckpoint)
264 if (mapOrphanBlocks.count(hashPendingCheckpoint)
265 && hashBlock == WantedByOrphan(mapOrphanBlocks[hashPendingCheckpoint]))
270 // ppcoin: reset synchronized checkpoint to last hardened checkpoint
271 bool ResetSyncCheckpoint()
273 LOCK(cs_hashSyncCheckpoint);
274 const uint256& hash = mapCheckpoints.rbegin()->second.first;
275 if (mapBlockIndex.count(hash) && !mapBlockIndex[hash]->IsInMainChain())
277 // checkpoint block accepted but not yet in main chain
278 printf("ResetSyncCheckpoint: SetBestChain to hardened checkpoint %s\n", hash.ToString().c_str());
281 if (!block.ReadFromDisk(mapBlockIndex[hash]))
282 return error("ResetSyncCheckpoint: ReadFromDisk failed for hardened checkpoint %s", hash.ToString().c_str());
283 if (!block.SetBestChain(txdb, mapBlockIndex[hash]))
285 return error("ResetSyncCheckpoint: SetBestChain failed for hardened checkpoint %s", hash.ToString().c_str());
288 else if(!mapBlockIndex.count(hash))
290 // checkpoint block not yet accepted
291 hashPendingCheckpoint = hash;
292 checkpointMessagePending.SetNull();
293 printf("ResetSyncCheckpoint: pending for sync-checkpoint %s\n", hashPendingCheckpoint.ToString().c_str());
296 BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, mapCheckpoints)
298 const uint256& hash = i.second.first;
299 if (mapBlockIndex.count(hash) && mapBlockIndex[hash]->IsInMainChain())
301 if (!WriteSyncCheckpoint(hash))
302 return error("ResetSyncCheckpoint: failed to write sync checkpoint %s", hash.ToString().c_str());
303 printf("ResetSyncCheckpoint: sync-checkpoint reset to %s\n", hashSyncCheckpoint.ToString().c_str());
311 void AskForPendingSyncCheckpoint(CNode* pfrom)
313 LOCK(cs_hashSyncCheckpoint);
314 if (pfrom && hashPendingCheckpoint != 0 && (!mapBlockIndex.count(hashPendingCheckpoint)) && (!mapOrphanBlocks.count(hashPendingCheckpoint)))
315 pfrom->AskFor(CInv(MSG_BLOCK, hashPendingCheckpoint));
318 bool SetCheckpointPrivKey(std::string strPrivKey)
320 // Test signing a sync-checkpoint with genesis block
321 CSyncCheckpoint checkpoint;
322 checkpoint.hashCheckpoint = !fTestNet ? hashGenesisBlock : hashGenesisBlockTestNet;
323 CDataStream sMsg(SER_NETWORK, PROTOCOL_VERSION);
324 sMsg << (CUnsignedSyncCheckpoint)checkpoint;
325 checkpoint.vchMsg = std::vector<unsigned char>(sMsg.begin(), sMsg.end());
327 std::vector<unsigned char> vchPrivKey = ParseHex(strPrivKey);
329 key.SetPrivKey(CPrivKey(vchPrivKey.begin(), vchPrivKey.end())); // if key is not correct openssl may crash
330 if (!key.Sign(Hash(checkpoint.vchMsg.begin(), checkpoint.vchMsg.end()), checkpoint.vchSig))
333 // Test signing successful, proceed
334 CSyncCheckpoint::strMasterPrivKey = strPrivKey;
338 bool SendSyncCheckpoint(uint256 hashCheckpoint)
340 CSyncCheckpoint checkpoint;
341 checkpoint.hashCheckpoint = hashCheckpoint;
342 CDataStream sMsg(SER_NETWORK, PROTOCOL_VERSION);
343 sMsg << (CUnsignedSyncCheckpoint)checkpoint;
344 checkpoint.vchMsg = std::vector<unsigned char>(sMsg.begin(), sMsg.end());
346 if (CSyncCheckpoint::strMasterPrivKey.empty())
347 return error("SendSyncCheckpoint: Checkpoint master key unavailable.");
348 std::vector<unsigned char> vchPrivKey = ParseHex(CSyncCheckpoint::strMasterPrivKey);
350 key.SetPrivKey(CPrivKey(vchPrivKey.begin(), vchPrivKey.end())); // if key is not correct openssl may crash
351 if (!key.Sign(Hash(checkpoint.vchMsg.begin(), checkpoint.vchMsg.end()), checkpoint.vchSig))
352 return error("SendSyncCheckpoint: Unable to sign checkpoint, check private key?");
354 if(!checkpoint.ProcessSyncCheckpoint(NULL))
356 printf("WARNING: SendSyncCheckpoint: Failed to process checkpoint.\n");
363 for (std::vector<CNode*>::iterator it = vNodes.begin(); it != vNodes.end(); ++it)
364 checkpoint.RelayTo(*it);
369 // Is the sync-checkpoint outside maturity window?
370 bool IsMatureSyncCheckpoint()
372 LOCK(cs_hashSyncCheckpoint);
373 // sync-checkpoint should always be accepted block
374 assert(mapBlockIndex.count(hashSyncCheckpoint));
375 const CBlockIndex* pindexSync = mapBlockIndex[hashSyncCheckpoint];
376 return (nBestHeight >= pindexSync->nHeight + nCoinbaseMaturity ||
377 pindexSync->GetBlockTime() + nStakeMinAge < GetAdjustedTime());
381 // ppcoin: sync-checkpoint master key
382 const std::string CSyncCheckpoint::strMasterPubKey = "04a51b735f816de4ec3f891d5b38bbc91e1f7245c7c08d17990760b86b4d8fc3910a850ffecf73bfa8886f01739a0c4c4322201282d07b6e48ce931cc92af94850";
384 std::string CSyncCheckpoint::strMasterPrivKey = "";
386 // ppcoin: verify signature of sync-checkpoint message
387 bool CSyncCheckpoint::CheckSignature()
389 CPubKey key(ParseHex(CSyncCheckpoint::strMasterPubKey));
390 if (!key.Verify(Hash(vchMsg.begin(), vchMsg.end()), vchSig))
391 return error("CSyncCheckpoint::CheckSignature() : verify signature failed");
393 // Now unserialize the data
394 CDataStream sMsg(vchMsg, SER_NETWORK, PROTOCOL_VERSION);
395 sMsg >> *(CUnsignedSyncCheckpoint*)this;
399 // process synchronized checkpoint
400 bool CSyncCheckpoint::ProcessSyncCheckpoint(CNode* pfrom)
402 if (!CheckSignature())
405 LOCK(Checkpoints::cs_hashSyncCheckpoint);
406 if (!mapBlockIndex.count(hashCheckpoint))
408 // We haven't received the checkpoint chain, keep the checkpoint as pending
409 Checkpoints::hashPendingCheckpoint = hashCheckpoint;
410 Checkpoints::checkpointMessagePending = *this;
411 printf("ProcessSyncCheckpoint: pending for sync-checkpoint %s\n", hashCheckpoint.ToString().c_str());
412 // Ask this guy to fill in what we're missing
415 pfrom->PushGetBlocks(pindexBest, hashCheckpoint);
416 // ask directly as well in case rejected earlier by duplicate
417 // proof-of-stake because getblocks may not get it this time
418 pfrom->AskFor(CInv(MSG_BLOCK, mapOrphanBlocks.count(hashCheckpoint)? WantedByOrphan(mapOrphanBlocks[hashCheckpoint]) : hashCheckpoint));
423 if (!Checkpoints::ValidateSyncCheckpoint(hashCheckpoint))
427 CBlockIndex* pindexCheckpoint = mapBlockIndex[hashCheckpoint];
428 if (!pindexCheckpoint->IsInMainChain())
430 // checkpoint chain received but not yet main chain
432 if (!block.ReadFromDisk(pindexCheckpoint))
433 return error("ProcessSyncCheckpoint: ReadFromDisk failed for sync checkpoint %s", hashCheckpoint.ToString().c_str());
434 if (!block.SetBestChain(txdb, pindexCheckpoint))
436 Checkpoints::hashInvalidCheckpoint = hashCheckpoint;
437 return error("ProcessSyncCheckpoint: SetBestChain failed for sync checkpoint %s", hashCheckpoint.ToString().c_str());
441 if (!Checkpoints::WriteSyncCheckpoint(hashCheckpoint))
442 return error("ProcessSyncCheckpoint(): failed to write sync checkpoint %s", hashCheckpoint.ToString().c_str());
443 Checkpoints::checkpointMessage = *this;
444 Checkpoints::hashPendingCheckpoint = 0;
445 Checkpoints::checkpointMessagePending.SetNull();
446 printf("ProcessSyncCheckpoint: sync-checkpoint at %s\n", hashCheckpoint.ToString().c_str());