tolerate miner fees within 5x of each other

core/src/main/java/haveno/core/support/dispute/arbitration/ArbitrationManager.java

@@ -487,10 +487,8 @@ public final class ArbitrationManager extends DisputeManager<ArbitrationDisputeL
                 log.warn("Could not recreate dispute payout tx to verify fee: {}\n", e.getMessage(), e);
             }
             if (feeEstimateTx != null) {
-                BigInteger feeEstimate = feeEstimateTx.getFee();
+                HavenoUtils.verifyMinerFee(feeEstimateTx.getFee(), arbitratorSignedPayoutTx.getFee());
-                double feeDiff = arbitratorSignedPayoutTx.getFee().subtract(feeEstimate).abs().doubleValue() / feeEstimate.doubleValue();
+                log.info("Dispute payout tx fee {} is within tolerance");
-                if (feeDiff > XmrWalletService.MINER_FEE_TOLERANCE) throw new RuntimeException("Miner fee is not within " + (XmrWalletService.MINER_FEE_TOLERANCE * 100) + "% of estimated fee, expected " + feeEstimate + " but was " + arbitratorSignedPayoutTx.getFee());
-                log.info("Payout tx fee {} is within tolerance, diff %={}", arbitratorSignedPayoutTx.getFee(), feeDiff);
             }
         } else {
             disputeTxSet.setMultisigTxHex(trade.getPayoutTxHex());

core/src/main/java/haveno/core/trade/HavenoUtils.java

@@ -96,6 +96,7 @@ public class HavenoUtils {
     public static final double MAKER_FEE_PCT = 0.0015; // 0.15%
     public static final double TAKER_FEE_PCT = 0.0075; // 0.75%
     public static final double MAKER_FEE_FOR_TAKER_WITHOUT_DEPOSIT_PCT = MAKER_FEE_PCT + TAKER_FEE_PCT; // customize maker's fee when no deposit or fee from taker
+    public static final double MINER_FEE_TOLERANCE_FACTOR = 5.0; // miner fees must be within 5x of each other
 
     // other configuration
     public static final long LOG_POLL_ERROR_PERIOD_MS = 1000 * 60 * 4; // log poll errors up to once every 4 minutes
@@ -650,4 +651,16 @@ public class HavenoUtils {
             }
         }).start();
     }
+
+    public static void verifyMinerFee(BigInteger expected, BigInteger actual) {
+        BigInteger max = expected.max(actual);
+        BigInteger min = expected.min(actual);
+        if (min.compareTo(BigInteger.ZERO) <= 0) {
+            throw new IllegalArgumentException("Miner fees must be greater than zero");
+        }
+        double factor = divide(max, min);
+        if (factor > MINER_FEE_TOLERANCE_FACTOR) {
+            throw new IllegalArgumentException("Miner fees are not within " + MINER_FEE_TOLERANCE_FACTOR + "x of each other. Expected=" + expected + ", actual=" + actual + ", factor=" + factor);
+        }
+    }
 }

core/src/main/java/haveno/core/trade/Trade.java

@@ -1457,10 +1457,8 @@ public abstract class Trade extends XmrWalletBase implements Tradable, Model {
                 log.info("Creating fee estimate tx for {} {}", getClass().getSimpleName(), getId());
                 saveWallet(); // save wallet before creating fee estimate tx
                 MoneroTxWallet feeEstimateTx = createPayoutTx();
-                BigInteger feeEstimate = feeEstimateTx.getFee();
+                HavenoUtils.verifyMinerFee(feeEstimateTx.getFee(), payoutTx.getFee());
-                double feeDiff = payoutTx.getFee().subtract(feeEstimate).abs().doubleValue() / feeEstimate.doubleValue(); // TODO: use BigDecimal?
+                log.info("Payout tx fee {} is within tolerance");
-                if (feeDiff > XmrWalletService.MINER_FEE_TOLERANCE) throw new IllegalArgumentException("Miner fee is not within " + (XmrWalletService.MINER_FEE_TOLERANCE * 100) + "% of estimated fee, expected " + feeEstimate + " but was " + payoutTx.getFee());
-                log.info("Payout tx fee {} is within tolerance, diff %={}", payoutTx.getFee(), feeDiff);
             }
 
             // set signed payout tx hex

core/src/main/java/haveno/core/xmr/wallet/XmrWalletService.java

@@ -110,7 +110,6 @@ public class XmrWalletService extends XmrWalletBase {
     public static final String MONERO_BINS_DIR = Config.appDataDir().getAbsolutePath();
     public static final String MONERO_WALLET_RPC_NAME = Utilities.isWindows() ? "monero-wallet-rpc.exe" : "monero-wallet-rpc";
     public static final String MONERO_WALLET_RPC_PATH = MONERO_BINS_DIR + File.separator + MONERO_WALLET_RPC_NAME;
-    public static final double MINER_FEE_TOLERANCE = 0.25; // miner fee must be within percent of estimated fee
     public static final MoneroTxPriority PROTOCOL_FEE_PRIORITY = MoneroTxPriority.DEFAULT;
     public static final int MONERO_LOG_LEVEL = -1; // monero library log level, -1 to disable
     private static final MoneroNetworkType MONERO_NETWORK_TYPE = getMoneroNetworkType();
@@ -767,9 +766,8 @@ public class XmrWalletService extends XmrWalletBase {
 
                 // verify miner fee
                 BigInteger minerFeeEstimate = getFeeEstimate(tx.getWeight());
-                double minerFeeDiff = tx.getFee().subtract(minerFeeEstimate).abs().doubleValue() / minerFeeEstimate.doubleValue();
+                HavenoUtils.verifyMinerFee(minerFeeEstimate, tx.getFee());
-                if (minerFeeDiff > MINER_FEE_TOLERANCE) throw new RuntimeException("Miner fee is not within " + (MINER_FEE_TOLERANCE * 100) + "% of estimated fee, expected " + minerFeeEstimate + " but was " + tx.getFee() + ", diff%=" + minerFeeDiff);
+                log.info("Trade miner fee {} is within tolerance");
-                log.info("Trade miner fee {} is within tolerance, diff%={}", tx.getFee(), minerFeeDiff);
 
                 // verify proof to fee address
                 BigInteger actualTradeFee = BigInteger.ZERO;