// Safety limits
unsigned int nSize = ::GetSerializeSize(*this, SER_NETWORK);
- if (GetSigOpCount() > 2 || nSize < 100)
+ // Checking ECDSA signatures is a CPU bottleneck, so to avoid denial-of-service
+ // attacks disallow transactions with more than one SigOp per 34 bytes.
+ // 34 bytes because a TxOut is:
+ // 20-byte address + 8 byte bitcoin amount + 5 bytes of ops + 1 byte script length
+ if (GetSigOpCount() > nSize / 34 || nSize < 100)
return error("AcceptToMemoryPool() : nonstandard transaction");
// Rather not work on nonstandard transactions
int64 n = pcoin->GetCredit();
if (n <= 0)
continue;
- if (n < nTargetValue)
- {
- vValue.push_back(make_pair(n, pcoin));
- nTotalLower += n;
- }
- else if (n == nTargetValue)
+ if (n == nTargetValue)
{
setCoinsRet.insert(pcoin);
return true;
}
+ else if (n < nTargetValue + CENT)
+ {
+ vValue.push_back(make_pair(n, pcoin));
+ nTotalLower += n;
+ }
else if (n < nLowestLarger)
{
nLowestLarger = n;
}
}
- if (nTotalLower < nTargetValue)
+ if (nTotalLower == nTargetValue || nTotalLower == nTargetValue + CENT)
+ {
+ for (int i = 0; i < vValue.size(); ++i)
+ setCoinsRet.insert(vValue[i].second);
+ return true;
+ }
+
+ if (nTotalLower < nTargetValue + (pcoinLowestLarger ? CENT : 0))
{
if (pcoinLowestLarger == NULL)
return false;
return true;
}
+ if (nTotalLower >= nTargetValue + CENT)
+ nTargetValue += CENT;
+
// Solve subset sum by stochastic approximation
sort(vValue.rbegin(), vValue.rend());
vector<char> vfIncluded;
-bool CreateTransaction(CScript scriptPubKey, int64 nValue, CWalletTx& wtxNew, CReserveKey& reservekey, int64& nFeeRet)
+bool CreateTransaction(const vector<pair<CScript, int64> >& vecSend, CWalletTx& wtxNew, CReserveKey& reservekey, int64& nFeeRet)
{
+ int64 nValue = 0;
+ foreach (const PAIRTYPE(CScript, int64)& s, vecSend)
+ {
+ if (nValue < 0)
+ return false;
+ nValue += s.second;
+ }
+ if (vecSend.empty() || nValue < 0)
+ return false;
+
CRITICAL_BLOCK(cs_main)
{
// txdb must be opened before the mapWallet lock
wtxNew.vin.clear();
wtxNew.vout.clear();
wtxNew.fFromMe = true;
- if (nValue < 0)
- return false;
- int64 nValueOut = nValue;
+
int64 nTotalValue = nValue + nFeeRet;
double dPriority = 0;
+ // vouts to the payees
+ foreach (const PAIRTYPE(CScript, int64)& s, vecSend)
+ wtxNew.vout.push_back(CTxOut(s.second, s.first));
// Choose coins to use
set<CWalletTx*> setCoins;
dPriority += (double)nCredit * pcoin->GetDepthInMainChain();
}
- // Fill a vout to the payee
- bool fChangeFirst = GetRand(2);
- if (!fChangeFirst)
- wtxNew.vout.push_back(CTxOut(nValueOut, scriptPubKey));
-
// Fill a vout back to self with any change
int64 nChange = nValueIn - nTotalValue;
if (nChange >= CENT)
// Fill a vout to ourself, using same address type as the payment
CScript scriptChange;
- if (scriptPubKey.GetBitcoinAddressHash160() != 0)
+ if (vecSend[0].first.GetBitcoinAddressHash160() != 0)
scriptChange.SetBitcoinAddress(vchPubKey);
else
scriptChange << vchPubKey << OP_CHECKSIG;
- wtxNew.vout.push_back(CTxOut(nChange, scriptChange));
+
+ // Insert change txn at random position:
+ vector<CTxOut>::iterator position = wtxNew.vout.begin()+GetRandInt(wtxNew.vout.size());
+ wtxNew.vout.insert(position, CTxOut(nChange, scriptChange));
}
else
reservekey.ReturnKey();
- // Fill a vout to the payee
- if (fChangeFirst)
- wtxNew.vout.push_back(CTxOut(nValueOut, scriptPubKey));
-
// Fill vin
foreach(CWalletTx* pcoin, setCoins)
for (int nOut = 0; nOut < pcoin->vout.size(); nOut++)
return true;
}
+bool CreateTransaction(CScript scriptPubKey, int64 nValue, CWalletTx& wtxNew, CReserveKey& reservekey, int64& nFeeRet)
+{
+ vector< pair<CScript, int64> > vecSend;
+ vecSend.push_back(make_pair(scriptPubKey, nValue));
+ return CreateTransaction(vecSend, wtxNew, reservekey, nFeeRet);
+}
+
// Call after CreateTransaction unless you want to abort
bool CommitTransaction(CWalletTx& wtxNew, CReserveKey& reservekey)
{