sweep: account for all script types in craftSweepTx

With this change, transactions created via craftSweepTx will be
standard. Previously, p2wsh/p2pkh scripts passed in via SendCoins would
be weighted as p2wpkh scripts. With a feerate of 1 sat/vbyte,
transactions returned would be non-standard. Luckily, the critical
sweeper subsystem only used p2wpkh scripts so this only affected
callers from the rpcserver.

Also added is an integration test that fails if SendCoins manages
to generate a non-standard transaction. All script types are now
accounted for in getWeightEstimate, which now errors if an unknown
script type is passed in.

lntest/itest/lnd_nonstd_sweep_test.go

@@ -0,0 +1,147 @@
+package itest
+
+import (
+	"context"
+	"testing"
+
+	"github.com/btcsuite/btcd/btcutil"
+	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lntest"
+	"github.com/stretchr/testify/require"
+)
+
+func testNonstdSweep(net *lntest.NetworkHarness, t *harnessTest) {
+	p2shAddr, err := btcutil.NewAddressScriptHash(
+		make([]byte, 1), harnessNetParams,
+	)
+	require.NoError(t.t, err)
+
+	p2pkhAddr, err := btcutil.NewAddressPubKeyHash(
+		make([]byte, 20), harnessNetParams,
+	)
+	require.NoError(t.t, err)
+
+	p2wshAddr, err := btcutil.NewAddressWitnessScriptHash(
+		make([]byte, 32), harnessNetParams,
+	)
+	require.NoError(t.t, err)
+
+	p2wkhAddr, err := btcutil.NewAddressWitnessPubKeyHash(
+		make([]byte, 20), harnessNetParams,
+	)
+	require.NoError(t.t, err)
+
+	p2trAddr, err := btcutil.NewAddressTaproot(
+		make([]byte, 32), harnessNetParams,
+	)
+	require.NoError(t.t, err)
+
+	tests := []struct {
+		name    string
+		address string
+	}{
+		{
+			name:    "p2sh SendCoins standardness",
+			address: p2shAddr.EncodeAddress(),
+		},
+		{
+			name:    "p2pkh SendCoins standardness",
+			address: p2pkhAddr.EncodeAddress(),
+		},
+		{
+			name:    "p2wsh SendCoins standardness",
+			address: p2wshAddr.EncodeAddress(),
+		},
+		{
+			name:    "p2wkh SendCoins standardness",
+			address: p2wkhAddr.EncodeAddress(),
+		},
+		{
+			name:    "p2tr SendCoins standardness",
+			address: p2trAddr.EncodeAddress(),
+		},
+	}
+
+	for _, test := range tests {
+		test := test
+		success := t.t.Run(test.name, func(t *testing.T) {
+			h := newHarnessTest(t, net)
+
+			testNonStdSweepInner(net, h, test.address)
+		})
+		if !success {
+			break
+		}
+	}
+}
+
+func testNonStdSweepInner(net *lntest.NetworkHarness, t *harnessTest,
+	address string) {
+
+	ctxb := context.Background()
+
+	carol := net.NewNode(t.t, "carol", nil)
+
+	// Give Carol a UTXO so SendCoins will behave as expected.
+	net.SendCoins(t.t, btcutil.SatoshiPerBitcoin, carol)
+
+	// Set the fee estimate to 1sat/vbyte.
+	net.SetFeeEstimate(250)
+
+	// Make Carol call SendCoins with the SendAll flag and the created
+	// address.
+	sendReq := &lnrpc.SendCoinsRequest{
+		Addr:        address,
+		SatPerVbyte: 1,
+		SendAll:     true,
+	}
+
+	ctxt, cancel := context.WithTimeout(ctxb, defaultTimeout)
+	defer cancel()
+
+	// If a non-standard transaction was created, then this SendCoins call
+	// will fail.
+	_, err := carol.SendCoins(ctxt, sendReq)
+	require.NoError(t.t, err)
+
+	// Fetch the txid so we can grab the raw transaction.
+	txid, err := waitForTxInMempool(net.Miner.Client, minerMempoolTimeout)
+	require.NoError(t.t, err)
+
+	tx, err := net.Miner.Client.GetRawTransaction(txid)
+	require.NoError(t.t, err)
+
+	msgTx := tx.MsgTx()
+
+	// Fetch the fee of the transaction.
+	var (
+		inputVal  int
+		outputVal int
+		fee       int
+	)
+
+	for _, inp := range msgTx.TxIn {
+		// Fetch the previous outpoint's value.
+		prevOut := inp.PreviousOutPoint
+
+		ptx, err := net.Miner.Client.GetRawTransaction(&prevOut.Hash)
+		require.NoError(t.t, err)
+
+		pout := ptx.MsgTx().TxOut[prevOut.Index]
+		inputVal += int(pout.Value)
+	}
+
+	for _, outp := range msgTx.TxOut {
+		outputVal += int(outp.Value)
+	}
+
+	fee = inputVal - outputVal
+
+	// Fetch the vsize of the transaction so we can determine if the
+	// transaction pays >= 1 sat/vbyte.
+	rawTx, err := net.Miner.Client.GetRawTransactionVerbose(txid)
+	require.NoError(t.t, err)
+
+	// Require fee >= vbytes.
+	require.True(t.t, fee >= int(rawTx.Vsize))
+}

lntest/itest/lnd_test_list_on_test.go

@@ -427,4 +427,8 @@ var allTestCases = []*testCase{
 		name: "scid alias upgrade",
 		test: testOptionScidUpgrade,
 	},
+	{
+		name: "nonstd sweep",
+		test: testNonstdSweep,
+	},
 }