Merge pull request #5485

aa279d6 Enforce minRelayTxFee on wallet created tx and add a maxtxfee option. (Gregory Maxwell)

1 files changed, 28 insertions, 19 deletions

diff --git a/src/wallet.cpp b/src/wallet.cpp
index 9b9a1d1735..8504c0a287 100644
--- a/src/wallet.cpp
+++ b/src/wallet.cpp
@@ -26,6 +26,7 @@ using namespace std;
  * Settings
  */
 CFeeRate payTxFee(DEFAULT_TRANSACTION_FEE);
+CAmount maxTxFee = DEFAULT_TRANSACTION_MAXFEE;
 unsigned int nTxConfirmTarget = 1;
 bool bSpendZeroConfChange = true;
 bool fSendFreeTransactions = false;
@@ -1525,27 +1526,32 @@ bool CWallet::CreateTransaction(const vector<pair<CScript, CAmount> >& vecSend,
                 }
                 dPriority = wtxNew.ComputePriority(dPriority, nBytes);
 
-                CAmount nFeeNeeded = GetMinimumFee(nBytes, nTxConfirmTarget, mempool);
+                // Can we complete this as a free transaction?
+                if (fSendFreeTransactions && nBytes <= MAX_FREE_TRANSACTION_CREATE_SIZE)
+                {
+                    // Not enough fee: enough priority?
+                    double dPriorityNeeded = mempool.estimatePriority(nTxConfirmTarget);
+                    // Not enough mempool history to estimate: use hard-coded AllowFree.
+                    if (dPriorityNeeded <= 0 && AllowFree(dPriority))
+                        break;
+
+                    // Small enough, and priority high enough, to send for free
+                    if (dPriorityNeeded > 0 && dPriority >= dPriorityNeeded)
+                        break;
+                }
 
-                if (nFeeRet >= nFeeNeeded)
-                    break; // Done, enough fee included.
+                CAmount nFeeNeeded = GetMinimumFee(nBytes, nTxConfirmTarget, mempool);
 
-                // Too big to send for free? Include more fee and try again:
-                if (!fSendFreeTransactions || nBytes > MAX_FREE_TRANSACTION_CREATE_SIZE)
+                // If we made it here and we aren't even able to meet the relay fee on the next pass, give up
+                // because we must be at the maximum allowed fee.
+                if (nFeeNeeded < ::minRelayTxFee.GetFee(nBytes))
                 {
-                    nFeeRet = nFeeNeeded;
-                    continue;
+                    strFailReason = _("Transaction too large for fee policy");
+                    return false;
                 }
 
-                // Not enough fee: enough priority?
-                double dPriorityNeeded = mempool.estimatePriority(nTxConfirmTarget);
-                // Not enough mempool history to estimate: use hard-coded AllowFree.
-                if (dPriorityNeeded <= 0 && AllowFree(dPriority))
-                    break;
-
-                // Small enough, and priority high enough, to send for free
-                if (dPriorityNeeded > 0 && dPriority >= dPriorityNeeded)
-                    break;
+                if (nFeeRet >= nFeeNeeded)
+                    break; // Done, enough fee included.
 
                 // Include more fee and try again.
                 nFeeRet = nFeeNeeded;
@@ -1617,9 +1623,6 @@ CAmount CWallet::GetMinimumFee(unsigned int nTxBytes, unsigned int nConfirmTarge
 {
     // payTxFee is user-set "I want to pay this much"
     CAmount nFeeNeeded = payTxFee.GetFee(nTxBytes);
-    // prevent user from paying a non-sense fee (like 1 satoshi): 0 < fee < minRelayFee
-    if (nFeeNeeded > 0 && nFeeNeeded < ::minRelayTxFee.GetFee(nTxBytes))
-        nFeeNeeded = ::minRelayTxFee.GetFee(nTxBytes);
     // user selected total at least (default=true)
     if (fPayAtLeastCustomFee && nFeeNeeded > 0 && nFeeNeeded < payTxFee.GetFeePerK())
         nFeeNeeded = payTxFee.GetFeePerK();
@@ -1630,6 +1633,12 @@ CAmount CWallet::GetMinimumFee(unsigned int nTxBytes, unsigned int nConfirmTarge
     // back to a hard-coded fee
     if (nFeeNeeded == 0)
         nFeeNeeded = minTxFee.GetFee(nTxBytes);
+    // prevent user from paying a non-sense fee (like 1 satoshi): 0 < fee < minRelayFee
+    if (nFeeNeeded < ::minRelayTxFee.GetFee(nTxBytes))
+        nFeeNeeded = ::minRelayTxFee.GetFee(nTxBytes);
+    // But always obey the maximum
+    if (nFeeNeeded > maxTxFee)
+        nFeeNeeded = maxTxFee;
     return nFeeNeeded;
 }