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) )
36 ( 143990, std::make_pair(uint256("0x00000000001ff5c3940a9f73ad4a990f64955179bde0f743c76dbf0031429efc"), 1418953493) )
39 // TestNet has no checkpoints
40 static MapCheckpoints mapCheckpointsTestnet =
41 boost::assign::map_list_of
42 ( 0, std::make_pair(hashGenesisBlockTestNet, 1360105017) )
45 bool CheckHardened(int nHeight, const uint256& hash)
47 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
49 MapCheckpoints::const_iterator i = checkpoints.find(nHeight);
50 if (i == checkpoints.end()) return true;
51 return hash == i->second.first;
54 int GetTotalBlocksEstimate()
56 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
58 return checkpoints.rbegin()->first;
61 int GetLastCheckpointTime()
63 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
65 return checkpoints.rbegin()->second.second;
68 CBlockIndex* GetLastCheckpoint(const std::map<uint256, CBlockIndex*>& mapBlockIndex)
70 MapCheckpoints& checkpoints = (fTestNet ? mapCheckpointsTestnet : mapCheckpoints);
72 BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, checkpoints)
74 const uint256& hash = i.second.first;
75 std::map<uint256, CBlockIndex*>::const_iterator t = mapBlockIndex.find(hash);
76 if (t != mapBlockIndex.end())
82 // ppcoin: synchronized checkpoint (centrally broadcasted)
83 uint256 hashSyncCheckpoint = 0;
84 uint256 hashPendingCheckpoint = 0;
85 CSyncCheckpoint checkpointMessage;
86 CSyncCheckpoint checkpointMessagePending;
87 uint256 hashInvalidCheckpoint = 0;
88 CCriticalSection cs_hashSyncCheckpoint;
90 // ppcoin: get last synchronized checkpoint
91 CBlockIndex* GetLastSyncCheckpoint()
93 LOCK(cs_hashSyncCheckpoint);
94 if (!mapBlockIndex.count(hashSyncCheckpoint))
95 error("GetSyncCheckpoint: block index missing for current sync-checkpoint %s", hashSyncCheckpoint.ToString().c_str());
97 return mapBlockIndex[hashSyncCheckpoint];
101 // ppcoin: only descendant of current sync-checkpoint is allowed
102 bool ValidateSyncCheckpoint(uint256 hashCheckpoint)
104 if (!mapBlockIndex.count(hashSyncCheckpoint))
105 return error("ValidateSyncCheckpoint: block index missing for current sync-checkpoint %s", hashSyncCheckpoint.ToString().c_str());
106 if (!mapBlockIndex.count(hashCheckpoint))
107 return error("ValidateSyncCheckpoint: block index missing for received sync-checkpoint %s", hashCheckpoint.ToString().c_str());
109 CBlockIndex* pindexSyncCheckpoint = mapBlockIndex[hashSyncCheckpoint];
110 CBlockIndex* pindexCheckpointRecv = mapBlockIndex[hashCheckpoint];
112 if (pindexCheckpointRecv->nHeight <= pindexSyncCheckpoint->nHeight)
114 // Received an older checkpoint, trace back from current checkpoint
115 // to the same height of the received checkpoint to verify
116 // that current checkpoint should be a descendant block
117 CBlockIndex* pindex = pindexSyncCheckpoint;
118 while (pindex->nHeight > pindexCheckpointRecv->nHeight)
119 if (!(pindex = pindex->pprev))
120 return error("ValidateSyncCheckpoint: pprev null - block index structure failure");
121 if (pindex->GetBlockHash() != hashCheckpoint)
123 hashInvalidCheckpoint = hashCheckpoint;
124 return error("ValidateSyncCheckpoint: new sync-checkpoint %s is conflicting with current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
126 return false; // ignore older checkpoint
129 // Received checkpoint should be a descendant block of the current
130 // checkpoint. Trace back to the same height of current checkpoint
132 CBlockIndex* pindex = pindexCheckpointRecv;
133 while (pindex->nHeight > pindexSyncCheckpoint->nHeight)
134 if (!(pindex = pindex->pprev))
135 return error("ValidateSyncCheckpoint: pprev2 null - block index structure failure");
136 if (pindex->GetBlockHash() != hashSyncCheckpoint)
138 hashInvalidCheckpoint = hashCheckpoint;
139 return error("ValidateSyncCheckpoint: new sync-checkpoint %s is not a descendant of current sync-checkpoint %s", hashCheckpoint.ToString().c_str(), hashSyncCheckpoint.ToString().c_str());
144 bool WriteSyncCheckpoint(const uint256& hashCheckpoint)
148 if (!txdb.WriteSyncCheckpoint(hashCheckpoint))
151 return error("WriteSyncCheckpoint(): failed to write to db sync checkpoint %s", hashCheckpoint.ToString().c_str());
153 if (!txdb.TxnCommit())
154 return error("WriteSyncCheckpoint(): failed to commit to db sync checkpoint %s", hashCheckpoint.ToString().c_str());
160 Checkpoints::hashSyncCheckpoint = hashCheckpoint;
164 bool AcceptPendingSyncCheckpoint()
166 LOCK(cs_hashSyncCheckpoint);
167 if (hashPendingCheckpoint != 0 && mapBlockIndex.count(hashPendingCheckpoint))
169 if (!ValidateSyncCheckpoint(hashPendingCheckpoint))
171 hashPendingCheckpoint = 0;
172 checkpointMessagePending.SetNull();
177 CBlockIndex* pindexCheckpoint = mapBlockIndex[hashPendingCheckpoint];
178 if (!pindexCheckpoint->IsInMainChain())
181 if (!block.ReadFromDisk(pindexCheckpoint))
182 return error("AcceptPendingSyncCheckpoint: ReadFromDisk failed for sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
183 if (!block.SetBestChain(txdb, pindexCheckpoint))
185 hashInvalidCheckpoint = hashPendingCheckpoint;
186 return error("AcceptPendingSyncCheckpoint: SetBestChain failed for sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
193 if (!WriteSyncCheckpoint(hashPendingCheckpoint))
194 return error("AcceptPendingSyncCheckpoint(): failed to write sync checkpoint %s", hashPendingCheckpoint.ToString().c_str());
195 hashPendingCheckpoint = 0;
196 checkpointMessage = checkpointMessagePending;
197 checkpointMessagePending.SetNull();
198 printf("AcceptPendingSyncCheckpoint : sync-checkpoint at %s\n", hashSyncCheckpoint.ToString().c_str());
199 // relay the checkpoint
200 if (!checkpointMessage.IsNull())
202 BOOST_FOREACH(CNode* pnode, vNodes)
203 checkpointMessage.RelayTo(pnode);
210 // Automatically select a suitable sync-checkpoint
211 uint256 AutoSelectSyncCheckpoint()
213 const CBlockIndex *pindex = pindexBest;
214 // Search backward for a block within max span and maturity window
215 while (pindex->pprev && (pindex->GetBlockTime() + CHECKPOINT_MAX_SPAN > pindexBest->GetBlockTime() || pindex->nHeight + 8 > pindexBest->nHeight))
216 pindex = pindex->pprev;
217 return pindex->GetBlockHash();
220 // Check against synchronized checkpoint
221 bool CheckSync(const uint256& hashBlock, const CBlockIndex* pindexPrev)
223 if (fTestNet) return true; // Testnet has no checkpoints
224 int nHeight = pindexPrev->nHeight + 1;
226 LOCK(cs_hashSyncCheckpoint);
227 // sync-checkpoint should always be accepted block
228 assert(mapBlockIndex.count(hashSyncCheckpoint));
229 const CBlockIndex* pindexSync = mapBlockIndex[hashSyncCheckpoint];
231 if (nHeight > pindexSync->nHeight)
233 // trace back to same height as sync-checkpoint
234 const CBlockIndex* pindex = pindexPrev;
235 while (pindex->nHeight > pindexSync->nHeight)
236 if (!(pindex = pindex->pprev))
237 return error("CheckSync: pprev null - block index structure failure");
238 if (pindex->nHeight < pindexSync->nHeight || pindex->GetBlockHash() != hashSyncCheckpoint)
239 return false; // only descendant of sync-checkpoint can pass check
241 if (nHeight == pindexSync->nHeight && hashBlock != hashSyncCheckpoint)
242 return false; // same height with sync-checkpoint
243 if (nHeight < pindexSync->nHeight && !mapBlockIndex.count(hashBlock))
244 return false; // lower height than sync-checkpoint
248 bool WantedByPendingSyncCheckpoint(uint256 hashBlock)
250 LOCK(cs_hashSyncCheckpoint);
251 if (hashPendingCheckpoint == 0)
253 if (hashBlock == hashPendingCheckpoint)
255 if (mapOrphanBlocks.count(hashPendingCheckpoint)
256 && hashBlock == WantedByOrphan(mapOrphanBlocks[hashPendingCheckpoint]))
261 // ppcoin: reset synchronized checkpoint to last hardened checkpoint
262 bool ResetSyncCheckpoint()
264 LOCK(cs_hashSyncCheckpoint);
265 const uint256& hash = mapCheckpoints.rbegin()->second.first;
266 if (mapBlockIndex.count(hash) && !mapBlockIndex[hash]->IsInMainChain())
268 // checkpoint block accepted but not yet in main chain
269 printf("ResetSyncCheckpoint: SetBestChain to hardened checkpoint %s\n", hash.ToString().c_str());
272 if (!block.ReadFromDisk(mapBlockIndex[hash]))
273 return error("ResetSyncCheckpoint: ReadFromDisk failed for hardened checkpoint %s", hash.ToString().c_str());
274 if (!block.SetBestChain(txdb, mapBlockIndex[hash]))
276 return error("ResetSyncCheckpoint: SetBestChain failed for hardened checkpoint %s", hash.ToString().c_str());
284 else if(!mapBlockIndex.count(hash))
286 // checkpoint block not yet accepted
287 hashPendingCheckpoint = hash;
288 checkpointMessagePending.SetNull();
289 printf("ResetSyncCheckpoint: pending for sync-checkpoint %s\n", hashPendingCheckpoint.ToString().c_str());
292 BOOST_REVERSE_FOREACH(const MapCheckpoints::value_type& i, mapCheckpoints)
294 const uint256& hash = i.second.first;
295 if (mapBlockIndex.count(hash) && mapBlockIndex[hash]->IsInMainChain())
297 if (!WriteSyncCheckpoint(hash))
298 return error("ResetSyncCheckpoint: failed to write sync checkpoint %s", hash.ToString().c_str());
299 printf("ResetSyncCheckpoint: sync-checkpoint reset to %s\n", hashSyncCheckpoint.ToString().c_str());
307 void AskForPendingSyncCheckpoint(CNode* pfrom)
309 LOCK(cs_hashSyncCheckpoint);
310 if (pfrom && hashPendingCheckpoint != 0 && (!mapBlockIndex.count(hashPendingCheckpoint)) && (!mapOrphanBlocks.count(hashPendingCheckpoint)))
311 pfrom->AskFor(CInv(MSG_BLOCK, hashPendingCheckpoint));
314 bool SetCheckpointPrivKey(std::string strPrivKey)
316 // Test signing a sync-checkpoint with genesis block
317 CSyncCheckpoint checkpoint;
318 checkpoint.hashCheckpoint = !fTestNet ? hashGenesisBlock : hashGenesisBlockTestNet;
319 CDataStream sMsg(SER_NETWORK, PROTOCOL_VERSION);
320 sMsg << (CUnsignedSyncCheckpoint)checkpoint;
321 checkpoint.vchMsg = std::vector<unsigned char>(sMsg.begin(), sMsg.end());
323 std::vector<unsigned char> vchPrivKey = ParseHex(strPrivKey);
325 key.SetPrivKey(CPrivKey(vchPrivKey.begin(), vchPrivKey.end())); // if key is not correct openssl may crash
326 if (!key.Sign(Hash(checkpoint.vchMsg.begin(), checkpoint.vchMsg.end()), checkpoint.vchSig))
329 // Test signing successful, proceed
330 CSyncCheckpoint::strMasterPrivKey = strPrivKey;
334 bool SendSyncCheckpoint(uint256 hashCheckpoint)
336 CSyncCheckpoint checkpoint;
337 checkpoint.hashCheckpoint = hashCheckpoint;
338 CDataStream sMsg(SER_NETWORK, PROTOCOL_VERSION);
339 sMsg << (CUnsignedSyncCheckpoint)checkpoint;
340 checkpoint.vchMsg = std::vector<unsigned char>(sMsg.begin(), sMsg.end());
342 if (CSyncCheckpoint::strMasterPrivKey.empty())
343 return error("SendSyncCheckpoint: Checkpoint master key unavailable.");
344 std::vector<unsigned char> vchPrivKey = ParseHex(CSyncCheckpoint::strMasterPrivKey);
346 key.SetPrivKey(CPrivKey(vchPrivKey.begin(), vchPrivKey.end())); // if key is not correct openssl may crash
347 if (!key.Sign(Hash(checkpoint.vchMsg.begin(), checkpoint.vchMsg.end()), checkpoint.vchSig))
348 return error("SendSyncCheckpoint: Unable to sign checkpoint, check private key?");
350 if(!checkpoint.ProcessSyncCheckpoint(NULL))
352 printf("WARNING: SendSyncCheckpoint: Failed to process checkpoint.\n");
359 BOOST_FOREACH(CNode* pnode, vNodes)
360 checkpoint.RelayTo(pnode);
365 // Is the sync-checkpoint outside maturity window?
366 bool IsMatureSyncCheckpoint()
368 LOCK(cs_hashSyncCheckpoint);
369 // sync-checkpoint should always be accepted block
370 assert(mapBlockIndex.count(hashSyncCheckpoint));
371 const CBlockIndex* pindexSync = mapBlockIndex[hashSyncCheckpoint];
372 return (nBestHeight >= pindexSync->nHeight + nCoinbaseMaturity ||
373 pindexSync->GetBlockTime() + nStakeMinAge < GetAdjustedTime());
377 // ppcoin: sync-checkpoint master key
378 const std::string CSyncCheckpoint::strMasterPubKey = "04a51b735f816de4ec3f891d5b38bbc91e1f7245c7c08d17990760b86b4d8fc3910a850ffecf73bfa8886f01739a0c4c4322201282d07b6e48ce931cc92af94850";
380 std::string CSyncCheckpoint::strMasterPrivKey = "";
382 // ppcoin: verify signature of sync-checkpoint message
383 bool CSyncCheckpoint::CheckSignature()
386 if (!key.SetPubKey(ParseHex(CSyncCheckpoint::strMasterPubKey)))
387 return error("CSyncCheckpoint::CheckSignature() : SetPubKey failed");
388 if (!key.Verify(Hash(vchMsg.begin(), vchMsg.end()), vchSig))
389 return error("CSyncCheckpoint::CheckSignature() : verify signature failed");
391 // Now unserialize the data
392 CDataStream sMsg(vchMsg, SER_NETWORK, PROTOCOL_VERSION);
393 sMsg >> *(CUnsignedSyncCheckpoint*)this;
397 // process synchronized checkpoint
398 bool CSyncCheckpoint::ProcessSyncCheckpoint(CNode* pfrom)
400 if (!CheckSignature())
403 LOCK(Checkpoints::cs_hashSyncCheckpoint);
404 if (!mapBlockIndex.count(hashCheckpoint))
406 // We haven't received the checkpoint chain, keep the checkpoint as pending
407 Checkpoints::hashPendingCheckpoint = hashCheckpoint;
408 Checkpoints::checkpointMessagePending = *this;
409 printf("ProcessSyncCheckpoint: pending for sync-checkpoint %s\n", hashCheckpoint.ToString().c_str());
410 // Ask this guy to fill in what we're missing
413 pfrom->PushGetBlocks(pindexBest, hashCheckpoint);
414 // ask directly as well in case rejected earlier by duplicate
415 // proof-of-stake because getblocks may not get it this time
416 pfrom->AskFor(CInv(MSG_BLOCK, mapOrphanBlocks.count(hashCheckpoint)? WantedByOrphan(mapOrphanBlocks[hashCheckpoint]) : hashCheckpoint));
421 if (!Checkpoints::ValidateSyncCheckpoint(hashCheckpoint))
425 CBlockIndex* pindexCheckpoint = mapBlockIndex[hashCheckpoint];
426 if (!pindexCheckpoint->IsInMainChain())
428 // checkpoint chain received but not yet main chain
430 if (!block.ReadFromDisk(pindexCheckpoint))
431 return error("ProcessSyncCheckpoint: ReadFromDisk failed for sync checkpoint %s", hashCheckpoint.ToString().c_str());
432 if (!block.SetBestChain(txdb, pindexCheckpoint))
434 Checkpoints::hashInvalidCheckpoint = hashCheckpoint;
435 return error("ProcessSyncCheckpoint: SetBestChain failed for sync checkpoint %s", hashCheckpoint.ToString().c_str());
443 if (!Checkpoints::WriteSyncCheckpoint(hashCheckpoint))
444 return error("ProcessSyncCheckpoint(): failed to write sync checkpoint %s", hashCheckpoint.ToString().c_str());
445 Checkpoints::checkpointMessage = *this;
446 Checkpoints::hashPendingCheckpoint = 0;
447 Checkpoints::checkpointMessagePending.SetNull();
448 printf("ProcessSyncCheckpoint: sync-checkpoint at %s\n", hashCheckpoint.ToString().c_str());