diff options
Diffstat (limited to 'src/main.cpp')
| -rw-r--r-- | src/main.cpp | 61 |
1 files changed, 34 insertions, 27 deletions
diff --git a/src/main.cpp b/src/main.cpp index e06c519ee2..336a5a9a86 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -72,6 +72,7 @@ const string strMessageMagic = "Bitcoin Signed Message:\n"; // Internal stuff namespace { + struct CBlockIndexWorkComparator { bool operator()(CBlockIndex *pa, CBlockIndex *pb) { @@ -120,7 +121,8 @@ namespace { }; map<uint256, pair<NodeId, list<QueuedBlock>::iterator> > mapBlocksInFlight; map<uint256, pair<NodeId, list<uint256>::iterator> > mapBlocksToDownload; -} + +} // anon namespace ////////////////////////////////////////////////////////////////////////////// // @@ -130,6 +132,7 @@ namespace { // These functions dispatch to one or all registered wallets namespace { + struct CMainSignals { // Notifies listeners of updated transaction data (transaction, and optionally the block it is found in. boost::signals2::signal<void (const CTransaction &, const CBlock *)> SyncTransaction; @@ -144,7 +147,8 @@ struct CMainSignals { // Tells listeners to broadcast their data. boost::signals2::signal<void ()> Broadcast; } g_signals; -} + +} // anon namespace void RegisterWallet(CWalletInterface* pwalletIn) { g_signals.SyncTransaction.connect(boost::bind(&CWalletInterface::SyncTransaction, pwalletIn, _1, _2)); @@ -274,7 +278,6 @@ void MarkBlockAsReceived(const uint256 &hash, NodeId nodeFrom = -1) { state->nLastBlockReceive = GetTimeMicros(); mapBlocksInFlight.erase(itInFlight); } - } // Requires cs_main. @@ -310,7 +313,7 @@ void MarkBlockAsInFlight(NodeId nodeid, const uint256 &hash) { mapBlocksInFlight[hash] = std::make_pair(nodeid, it); } -} +} // anon namespace bool GetNodeStateStats(NodeId nodeid, CNodeStateStats &stats) { LOCK(cs_main); @@ -488,7 +491,7 @@ bool IsStandardTx(const CTransaction& tx, string& reason) // Treat non-final transactions as non-standard to prevent a specific type // of double-spend attack, as well as DoS attacks. (if the transaction // can't be mined, the attacker isn't expending resources broadcasting it) - // Basically we don't want to propagate transactions that can't included in + // Basically we don't want to propagate transactions that can't be included in // the next block. // // However, IsFinalTx() is confusing... Without arguments, it uses @@ -521,7 +524,7 @@ bool IsStandardTx(const CTransaction& tx, string& reason) { // Biggest 'standard' txin is a 15-of-15 P2SH multisig with compressed // keys. (remember the 520 byte limit on redeemScript size) That works - // out to a (15*(33+1))+3=513 byte redeemScript, 513+1+15*(73+1)=1624 + // out to a (15*(33+1))+3=513 byte redeemScript, 513+1+15*(73+1)+3=1627 // bytes of scriptSig, which we round off to 1650 bytes for some minor // future-proofing. That's also enough to spend a 20-of-20 // CHECKMULTISIG scriptPubKey, though such a scriptPubKey is not @@ -583,15 +586,13 @@ bool IsFinalTx(const CTransaction &tx, int nBlockHeight, int64_t nBlockTime) } // -// Check transaction inputs, and make sure any -// pay-to-script-hash transactions are evaluating IsStandard scripts +// Check transaction inputs to mitigate two +// potential denial-of-service attacks: // -// Why bother? To avoid denial-of-service attacks; an attacker -// can submit a standard HASH... OP_EQUAL transaction, -// which will get accepted into blocks. The redemption -// script can be anything; an attacker could use a very -// expensive-to-check-upon-redemption script like: -// DUP CHECKSIG DROP ... repeated 100 times... OP_1 +// 1. scriptSigs with extra data stuffed into them, +// not consumed by scriptPubKey (or P2SH script) +// 2. P2SH scripts with a crazy number of expensive +// CHECKSIG/CHECKMULTISIG operations // bool AreInputsStandard(const CTransaction& tx, CCoinsViewCache& mapInputs) { @@ -615,8 +616,9 @@ bool AreInputsStandard(const CTransaction& tx, CCoinsViewCache& mapInputs) // Transactions with extra stuff in their scriptSigs are // non-standard. Note that this EvalScript() call will // be quick, because if there are any operations - // beside "push data" in the scriptSig the - // IsStandard() call returns false + // beside "push data" in the scriptSig + // IsStandard() will have already returned false + // and this method isn't called. vector<vector<unsigned char> > stack; if (!EvalScript(stack, tx.vin[i].scriptSig, tx, i, false, 0)) return false; @@ -628,16 +630,20 @@ bool AreInputsStandard(const CTransaction& tx, CCoinsViewCache& mapInputs) CScript subscript(stack.back().begin(), stack.back().end()); vector<vector<unsigned char> > vSolutions2; txnouttype whichType2; - if (!Solver(subscript, whichType2, vSolutions2)) - return false; - if (whichType2 == TX_SCRIPTHASH) - return false; - - int tmpExpected; - tmpExpected = ScriptSigArgsExpected(whichType2, vSolutions2); - if (tmpExpected < 0) - return false; - nArgsExpected += tmpExpected; + if (Solver(subscript, whichType2, vSolutions2)) + { + int tmpExpected = ScriptSigArgsExpected(whichType2, vSolutions2); + if (tmpExpected < 0) + return false; + nArgsExpected += tmpExpected; + } + else + { + // Any other Script with less than 15 sigops OK: + unsigned int sigops = subscript.GetSigOpCount(true); + // ... extra data left on the stack after execution is OK, too: + return (sigops <= MAX_P2SH_SIGOPS); + } } if (stack.size() != (unsigned int)nArgsExpected) @@ -3649,7 +3655,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv) if (pindex) pindex = chainActive.Next(pindex); int nLimit = 500; - LogPrint("net", "getblocks %d to %s limit %d\n", (pindex ? pindex->nHeight : -1), hashStop.ToString(), nLimit); + LogPrint("net", "getblocks %d to %s limit %d\n", (pindex ? pindex->nHeight : -1), hashStop==uint256(0) ? "end" : hashStop.ToString(), nLimit); for (; pindex; pindex = chainActive.Next(pindex)) { if (pindex->GetBlockHash() == hashStop) @@ -4038,6 +4044,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv) else { // Ignore unknown commands for extensibility + LogPrint("net", "Unknown command \"%s\" from peer=%d\n", SanitizeString(strCommand), pfrom->id); } |