internal/ethapi, accounts/abi/bind: cap highest gas limit by account …

…balance for 1559 fee parameters (ethereum#23309)

* internal/ethapi/api: cap highest gas limit by account balance for 1559 fee parameters

* accounts/abi/bind: port gas limit cap for 1559 parameters to simulated backend

* accounts/abi/bind: add test for 1559 gas estimates for the simulated backend

* internal/ethapi/api: fix comment

* accounts/abi/bind/backends, internal/ethapi: unify naming style

Co-authored-by: Péter Szilágyi <peterke@gmail.com>

accounts/abi/bind/backends/simulated.go

@@ -488,8 +488,19 @@ func (b *SimulatedBackend) EstimateGas(ctx context.Context, call ethereum.CallMs
 	} else {
 		hi = b.pendingBlock.GasLimit()
 	}
+	// Normalize the max fee per gas the call is willing to spend.
+	var feeCap *big.Int
+	if call.GasPrice != nil && (call.GasFeeCap != nil || call.GasTipCap != nil) {
+		return 0, errors.New("both gasPrice and (maxFeePerGas or maxPriorityFeePerGas) specified")
+	} else if call.GasPrice != nil {
+		feeCap = call.GasPrice
+	} else if call.GasFeeCap != nil {
+		feeCap = call.GasFeeCap
+	} else {
+		feeCap = common.Big0
+	}
 	// Recap the highest gas allowance with account's balance.
-	if call.GasPrice != nil && call.GasPrice.BitLen() != 0 {
+	if feeCap.BitLen() != 0 {
 		balance := b.pendingState.GetBalance(call.From) // from can't be nil
 		available := new(big.Int).Set(balance)
 		if call.Value != nil {
@@ -498,14 +509,14 @@ func (b *SimulatedBackend) EstimateGas(ctx context.Context, call ethereum.CallMs
 			}
 			available.Sub(available, call.Value)
 		}
-		allowance := new(big.Int).Div(available, call.GasPrice)
+		allowance := new(big.Int).Div(available, feeCap)
 		if allowance.IsUint64() && hi > allowance.Uint64() {
 			transfer := call.Value
 			if transfer == nil {
 				transfer = new(big.Int)
 			}
 			log.Warn("Gas estimation capped by limited funds", "original", hi, "balance", balance,
-				"sent", transfer, "gasprice", call.GasPrice, "fundable", allowance)
+				"sent", transfer, "feecap", feeCap, "fundable", allowance)
 			hi = allowance.Uint64()
 		}
 	}

accounts/abi/bind/backends/simulated_test.go

@@ -580,6 +580,26 @@ func TestEstimateGasWithPrice(t *testing.T) {
 			Value:    big.NewInt(100000000000),
 			Data:     nil,
 		}, 21000, errors.New("gas required exceeds allowance (10999)")}, // 10999=(2.2ether-1000wei)/(2e14)
+
+		{"EstimateEIP1559WithHighFees", ethereum.CallMsg{
+			From:      addr,
+			To:        &addr,
+			Gas:       0,
+			GasFeeCap: big.NewInt(1e14), // maxgascost = 2.1ether
+			GasTipCap: big.NewInt(1),
+			Value:     big.NewInt(1e17), // the remaining balance for fee is 2.1ether
+			Data:      nil,
+		}, params.TxGas, nil},
+
+		{"EstimateEIP1559WithSuperHighFees", ethereum.CallMsg{
+			From:      addr,
+			To:        &addr,
+			Gas:       0,
+			GasFeeCap: big.NewInt(1e14), // maxgascost = 2.1ether
+			GasTipCap: big.NewInt(1),
+			Value:     big.NewInt(1e17 + 1), // the remaining balance for fee is 2.1ether
+			Data:      nil,
+		}, params.TxGas, errors.New("gas required exceeds allowance (20999)")}, // 20999=(2.2ether-0.1ether-1wei)/(1e14)
 	}
 	for i, c := range cases {
 		got, err := sim.EstimateGas(context.Background(), c.message)
@@ -592,6 +612,9 @@ func TestEstimateGasWithPrice(t *testing.T) {
 			}
 			continue
 		}
+		if c.expectError == nil && err != nil {
+			t.Fatalf("test %d: didn't expect error, got %v", i, err)
+		}
 		if got != c.expect {
 			t.Fatalf("test %d: gas estimation mismatch, want %d, got %d", i, c.expect, got)
 		}

internal/ethapi/api.go

@@ -477,7 +477,7 @@ func (s *PrivateAccountAPI) SignTransaction(ctx context.Context, args Transactio
 	if args.Nonce == nil {
 		return nil, fmt.Errorf("nonce not specified")
 	}
-	// Before actually sign the transaction, ensure the transaction fee is reasonable.
+	// Before actually signing the transaction, ensure the transaction fee is reasonable.
 	tx := args.toTransaction()
 	if err := checkTxFee(tx.GasPrice(), tx.Gas(), s.b.RPCTxFeeCap()); err != nil {
 		return nil, err
@@ -1008,8 +1008,19 @@ func DoEstimateGas(ctx context.Context, b Backend, args TransactionArgs, blockNr
 		}
 		hi = block.GasLimit()
 	}
+	// Normalize the max fee per gas the call is willing to spend.
+	var feeCap *big.Int
+	if args.GasPrice != nil && (args.MaxFeePerGas != nil || args.MaxPriorityFeePerGas != nil) {
+		return 0, errors.New("both gasPrice and (maxFeePerGas or maxPriorityFeePerGas) specified")
+	} else if args.GasPrice != nil {
+		feeCap = args.GasPrice.ToInt()
+	} else if args.MaxFeePerGas != nil {
+		feeCap = args.MaxFeePerGas.ToInt()
+	} else {
+		feeCap = common.Big0
+	}
 	// Recap the highest gas limit with account's available balance.
-	if args.GasPrice != nil && args.GasPrice.ToInt().BitLen() != 0 {
+	if feeCap.BitLen() != 0 {
 		state, _, err := b.StateAndHeaderByNumberOrHash(ctx, blockNrOrHash)
 		if err != nil {
 			return 0, err
@@ -1022,7 +1033,7 @@ func DoEstimateGas(ctx context.Context, b Backend, args TransactionArgs, blockNr
 			}
 			available.Sub(available, args.Value.ToInt())
 		}
-		allowance := new(big.Int).Div(available, args.GasPrice.ToInt())
+		allowance := new(big.Int).Div(available, feeCap)
 
 		// If the allowance is larger than maximum uint64, skip checking
 		if allowance.IsUint64() && hi > allowance.Uint64() {
@@ -1031,7 +1042,7 @@ func DoEstimateGas(ctx context.Context, b Backend, args TransactionArgs, blockNr
 				transfer = new(hexutil.Big)
 			}
 			log.Warn("Gas estimation capped by limited funds", "original", hi, "balance", balance,
-				"sent", transfer.ToInt(), "gasprice", args.GasPrice.ToInt(), "fundable", allowance)
+				"sent", transfer.ToInt(), "maxFeePerGas", feeCap, "fundable", allowance)
 			hi = allowance.Uint64()
 		}
 	}