Merge pull request #915 from sipa/nooverwritetx
Do not allow overwriting unspent transactions
This commit is contained in:
commit
f2e81bad33
26
src/main.cpp
26
src/main.cpp
@ -976,8 +976,10 @@ bool CTransaction::DisconnectInputs(CTxDB& txdb)
|
||||
}
|
||||
|
||||
// Remove transaction from index
|
||||
if (!txdb.EraseTxIndex(*this))
|
||||
return error("DisconnectInputs() : EraseTxPos failed");
|
||||
// This can fail if a duplicate of this transaction was in a chain that got
|
||||
// reorganized away. This is only possible if this transaction was completely
|
||||
// spent, so erasing it would be a no-op anway.
|
||||
txdb.EraseTxIndex(*this);
|
||||
|
||||
return true;
|
||||
}
|
||||
@ -1256,6 +1258,26 @@ bool CBlock::ConnectBlock(CTxDB& txdb, CBlockIndex* pindex)
|
||||
if (!CheckBlock())
|
||||
return false;
|
||||
|
||||
// Do not allow blocks that contain transactions which 'overwrite' older transactions,
|
||||
// unless those are already completely spent.
|
||||
// If such overwrites are allowed, coinbases and transactions depending upon those
|
||||
// can be duplicated to remove the ability to spend the first instance -- even after
|
||||
// being sent to another address.
|
||||
// See BIP30 and http://r6.ca/blog/20120206T005236Z.html for more information.
|
||||
// This logic is not necessary for memory pool transactions, as AcceptToMemoryPool
|
||||
// already refuses previously-known transaction id's entirely.
|
||||
// This rule applies to all blocks whose timestamp is after March 15, 2012, 0:00 UTC.
|
||||
// On testnet it is enabled as of februari 20, 2012, 0:00 UTC.
|
||||
if (pindex->nTime > 1331769600 || (fTestNet && pindex->nTime > 1329696000))
|
||||
BOOST_FOREACH(CTransaction& tx, vtx)
|
||||
{
|
||||
CTxIndex txindexOld;
|
||||
if (txdb.ReadTxIndex(tx.GetHash(), txindexOld))
|
||||
BOOST_FOREACH(CDiskTxPos &pos, txindexOld.vSpent)
|
||||
if (pos.IsNull())
|
||||
return false;
|
||||
}
|
||||
|
||||
// To avoid being on the short end of a block-chain split,
|
||||
// don't do secondary validation of pay-to-script-hash transactions
|
||||
// until blocks with timestamps after paytoscripthashtime (see init.cpp for default).
|
||||
|
Loading…
Reference in New Issue
Block a user