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Move the AreInputsStandard documentation next to its implementation

0.16
esneider 8 years ago
parent
commit
ca67ddf0b7
  1. 33
      src/policy/policy.cpp

33
src/policy/policy.cpp

@ -52,23 +52,6 @@ bool IsDust(const CTxOut& txout, const CFeeRate& dustRelayFeeIn)
return (txout.nValue < GetDustThreshold(txout, dustRelayFeeIn)); return (txout.nValue < GetDustThreshold(txout, dustRelayFeeIn));
} }
/**
* Check transaction inputs to mitigate two
* potential denial-of-service attacks:
*
* 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
*
* 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
*/
bool IsStandard(const CScript& scriptPubKey, txnouttype& whichType, const bool witnessEnabled) bool IsStandard(const CScript& scriptPubKey, txnouttype& whichType, const bool witnessEnabled)
{ {
std::vector<std::vector<unsigned char> > vSolutions; std::vector<std::vector<unsigned char> > vSolutions;
@ -158,6 +141,22 @@ bool IsStandardTx(const CTransaction& tx, std::string& reason, const bool witnes
return true; return true;
} }
/**
* Check transaction inputs to mitigate two
* potential denial-of-service attacks:
*
* 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
*
* 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
*/
bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs) bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs)
{ {
if (tx.IsCoinBase()) if (tx.IsCoinBase())

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