diff --git a/src/core_read.cpp b/src/core_read.cpp index a8d667e3b..463871d17 100644 --- a/src/core_read.cpp +++ b/src/core_read.cpp @@ -88,10 +88,32 @@ CScript ParseScript(const std::string& s) return result; } +// Check that all of the input and output scripts of a transaction contains valid opcodes +bool CheckTxScriptsSanity(const CMutableTransaction& tx) +{ + // Check input scripts for non-coinbase txs + if (!CTransaction(tx).IsCoinBase()) { + for (unsigned int i = 0; i < tx.vin.size(); i++) { + if (!tx.vin[i].scriptSig.HasValidOps() || tx.vin[i].scriptSig.size() > MAX_SCRIPT_SIZE) { + return false; + } + } + } + // Check output scripts + for (unsigned int i = 0; i < tx.vout.size(); i++) { + if (!tx.vout[i].scriptPubKey.HasValidOps() || tx.vout[i].scriptPubKey.size() > MAX_SCRIPT_SIZE) { + return false; + } + } + + return true; +} + bool DecodeHexTx(CMutableTransaction& tx, const std::string& strHexTx, bool fTryNoWitness) { - if (!IsHex(strHexTx)) + if (!IsHex(strHexTx)) { return false; + } std::vector txData(ParseHex(strHexTx)); @@ -99,7 +121,7 @@ bool DecodeHexTx(CMutableTransaction& tx, const std::string& strHexTx, bool fTry CDataStream ssData(txData, SER_NETWORK, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS); try { ssData >> tx; - if (ssData.eof()) { + if (ssData.eof() && CheckTxScriptsSanity(tx)) { return true; } } @@ -111,8 +133,9 @@ bool DecodeHexTx(CMutableTransaction& tx, const std::string& strHexTx, bool fTry CDataStream ssData(txData, SER_NETWORK, PROTOCOL_VERSION); try { ssData >> tx; - if (!ssData.empty()) + if (!ssData.empty()) { return false; + } } catch (const std::exception&) { return false; diff --git a/src/script/script.cpp b/src/script/script.cpp index a71fee19c..a10b619f7 100644 --- a/src/script/script.cpp +++ b/src/script/script.cpp @@ -273,7 +273,8 @@ bool CScript::HasValidOps() const CScript::const_iterator it = begin(); while (it < end()) { opcodetype opcode; - if (!GetOp(it, opcode) || opcode > 0xb9) { + std::vector item; + if (!GetOp(it, opcode, item) || opcode > MAX_OPCODE || item.size() > MAX_SCRIPT_ELEMENT_SIZE) { return false; } } diff --git a/src/script/script.h b/src/script/script.h index 25b80ef62..23706b982 100644 --- a/src/script/script.h +++ b/src/script/script.h @@ -190,6 +190,9 @@ enum opcodetype OP_INVALIDOPCODE = 0xff, }; +// Maximum value that an opcode can be +static const unsigned int MAX_OPCODE = OP_NOP10; + const char* GetOpName(opcodetype opcode); class scriptnum_error : public std::runtime_error