lnd/lnwallet/btcwallet/psbt_test.go
2022-01-06 13:24:32 +01:00

338 lines
8.9 KiB
Go

package btcwallet
import (
"bytes"
"crypto/sha256"
"encoding/hex"
"fmt"
"testing"
"github.com/btcsuite/btcd/btcec"
"github.com/btcsuite/btcd/chaincfg"
"github.com/btcsuite/btcd/txscript"
"github.com/btcsuite/btcd/wire"
"github.com/btcsuite/btcutil"
"github.com/btcsuite/btcutil/psbt"
"github.com/btcsuite/btcwallet/waddrmgr"
"github.com/lightningnetwork/lnd/input"
"github.com/lightningnetwork/lnd/keychain"
"github.com/stretchr/testify/require"
)
var (
netParams = &chaincfg.RegressionNetParams
testValue int64 = 345678
testCSVTimeout uint32 = 2016
testCommitSecretBytes, _ = hex.DecodeString(
"9f1f0db609718cf70c580aec6a0e570c3f086ec85a2a6119295b1d64240d" +
"aca5",
)
testCommitSecret, testCommitPoint = btcec.PrivKeyFromBytes(
btcec.S256(), testCommitSecretBytes,
)
remoteRevocationBasePubKeyBytes, _ = hex.DecodeString(
"02baf067bfd1a6cf7229c7c459b106d384ad33e948ea1d561f2034475ff1" +
"7359fb",
)
remoteRevocationBasePubKey, _ = btcec.ParsePubKey(
remoteRevocationBasePubKeyBytes, btcec.S256(),
)
testTweakSingle, _ = hex.DecodeString(
"020143a30cf6b71ca2af01efbd1758a04b4c7f5c2299f2ea63a8a6b58107" +
"63b1ed",
)
)
// testInputType is a type that represents different types of inputs that are
// signed within a PSBT.
type testInputType uint8
const (
plainP2WKH testInputType = 0
tweakedP2WKH testInputType = 1
nestedP2WKH testInputType = 2
singleKeyP2WSH testInputType = 3
singleKeyDoubleTweakedP2WSH testInputType = 4
)
func (i testInputType) keyPath() []uint32 {
switch i {
case nestedP2WKH:
return []uint32{
hardenedKey(waddrmgr.KeyScopeBIP0049Plus.Purpose),
hardenedKey(0),
hardenedKey(0),
0, 0,
}
case singleKeyP2WSH:
return []uint32{
hardenedKey(keychain.BIP0043Purpose),
hardenedKey(netParams.HDCoinType),
hardenedKey(uint32(keychain.KeyFamilyPaymentBase)),
0, 7,
}
case singleKeyDoubleTweakedP2WSH:
return []uint32{
hardenedKey(keychain.BIP0043Purpose),
hardenedKey(netParams.HDCoinType),
hardenedKey(uint32(keychain.KeyFamilyDelayBase)),
0, 9,
}
default:
return []uint32{
hardenedKey(waddrmgr.KeyScopeBIP0084.Purpose),
hardenedKey(0),
hardenedKey(0),
0, 0,
}
}
}
func (i testInputType) output(t *testing.T,
privKey *btcec.PrivateKey) (*wire.TxOut, []byte) {
var (
addr btcutil.Address
witnessScript []byte
err error
)
switch i {
case plainP2WKH:
h := btcutil.Hash160(privKey.PubKey().SerializeCompressed())
addr, err = btcutil.NewAddressWitnessPubKeyHash(h, netParams)
require.NoError(t, err)
case tweakedP2WKH:
privKey = input.TweakPrivKey(privKey, testTweakSingle)
h := btcutil.Hash160(privKey.PubKey().SerializeCompressed())
addr, err = btcutil.NewAddressWitnessPubKeyHash(h, netParams)
require.NoError(t, err)
case nestedP2WKH:
h := btcutil.Hash160(privKey.PubKey().SerializeCompressed())
witnessAddr, err := btcutil.NewAddressWitnessPubKeyHash(
h, netParams,
)
require.NoError(t, err)
witnessProgram, err := txscript.PayToAddrScript(witnessAddr)
require.NoError(t, err)
addr, err = btcutil.NewAddressScriptHash(
witnessProgram, netParams,
)
require.NoError(t, err)
case singleKeyP2WSH:
// We're simulating a delay-to-self script which we're going to
// spend through the time lock path. We don't actually need to
// know the private key of the remote revocation base key.
revokeKey := input.DeriveRevocationPubkey(
remoteRevocationBasePubKey, testCommitPoint,
)
witnessScript, err = input.CommitScriptToSelf(
testCSVTimeout, privKey.PubKey(), revokeKey,
)
require.NoError(t, err)
h := sha256.Sum256(witnessScript)
addr, err = btcutil.NewAddressWitnessScriptHash(h[:], netParams)
require.NoError(t, err)
case singleKeyDoubleTweakedP2WSH:
// We're simulating breaching a remote party's delay-to-self
// output which we're going to spend through the revocation
// path. In that case the self key is the other party's self key
// and, we only know the revocation base private key and commit
// secret.
revokeKey := input.DeriveRevocationPubkey(
privKey.PubKey(), testCommitPoint,
)
witnessScript, err = input.CommitScriptToSelf(
testCSVTimeout, remoteRevocationBasePubKey, revokeKey,
)
require.NoError(t, err)
h := sha256.Sum256(witnessScript)
addr, err = btcutil.NewAddressWitnessScriptHash(h[:], netParams)
require.NoError(t, err)
default:
t.Fatalf("invalid input type")
}
pkScript, err := txscript.PayToAddrScript(addr)
require.NoError(t, err)
return &wire.TxOut{
Value: testValue,
PkScript: pkScript,
}, witnessScript
}
func (i testInputType) decorateInput(t *testing.T, privKey *btcec.PrivateKey,
in *psbt.PInput) {
switch i {
case tweakedP2WKH:
in.Unknowns = []*psbt.Unknown{{
Key: PsbtKeyTypeInputSignatureTweakSingle,
Value: testTweakSingle,
}}
case nestedP2WKH:
h := btcutil.Hash160(privKey.PubKey().SerializeCompressed())
witnessAddr, err := btcutil.NewAddressWitnessPubKeyHash(
h, netParams,
)
require.NoError(t, err)
witnessProgram, err := txscript.PayToAddrScript(witnessAddr)
require.NoError(t, err)
in.RedeemScript = witnessProgram
case singleKeyDoubleTweakedP2WSH:
in.Unknowns = []*psbt.Unknown{{
Key: PsbtKeyTypeInputSignatureTweakDouble,
Value: testCommitSecret.Serialize(),
}}
}
}
func (i testInputType) beforeFinalize(t *testing.T, packet *psbt.Packet) {
in := &packet.Inputs[0]
sigBytes := in.PartialSigs[0].Signature
pubKeyBytes := in.PartialSigs[0].PubKey
var witnessStack wire.TxWitness
switch i {
case singleKeyP2WSH:
witnessStack = make([][]byte, 3)
witnessStack[0] = sigBytes
witnessStack[1] = nil
witnessStack[2] = in.WitnessScript
case singleKeyDoubleTweakedP2WSH:
// Place a 1 as the first item in the evaluated witness stack to
// force script execution to the revocation clause.
witnessStack = make([][]byte, 3)
witnessStack[0] = sigBytes
witnessStack[1] = []byte{1}
witnessStack[2] = in.WitnessScript
default:
witnessStack = make([][]byte, 2)
witnessStack[0] = sigBytes
witnessStack[1] = pubKeyBytes
}
var err error
in.FinalScriptWitness, err = serializeTxWitness(witnessStack)
require.NoError(t, err)
}
// serializeTxWitness return the wire witness stack into raw bytes.
func serializeTxWitness(txWitness wire.TxWitness) ([]byte, error) {
var witnessBytes bytes.Buffer
err := psbt.WriteTxWitness(&witnessBytes, txWitness)
if err != nil {
return nil, fmt.Errorf("error serializing witness: %v", err)
}
return witnessBytes.Bytes(), nil
}
// TestSignPsbt tests the PSBT signing functionality.
func TestSignPsbt(t *testing.T) {
w, cleanup := newTestWallet(t, netParams, seedBytes)
defer cleanup()
testCases := []struct {
name string
inputType testInputType
}{{
name: "plain P2WKH",
inputType: plainP2WKH,
}, {
name: "tweaked P2WKH",
inputType: tweakedP2WKH,
}, {
name: "nested P2WKH",
inputType: nestedP2WKH,
}, {
name: "single key P2WSH",
inputType: singleKeyP2WSH,
}, {
name: "single key double tweaked P2WSH",
inputType: singleKeyDoubleTweakedP2WSH,
}}
for _, tc := range testCases {
tc := tc
// This is the private key we're going to sign with.
privKey, err := w.deriveKeyByBIP32Path(tc.inputType.keyPath())
require.NoError(t, err)
txOut, witnessScript := tc.inputType.output(t, privKey)
// Create the reference transaction that has the input that is
// going to be spent by our PSBT.
refTx := wire.NewMsgTx(2)
refTx.AddTxIn(&wire.TxIn{})
refTx.AddTxOut(txOut)
// Create the unsigned spend transaction that is going to be the
// main content of our PSBT.
spendTx := wire.NewMsgTx(2)
spendTx.LockTime = testCSVTimeout
spendTx.AddTxIn(&wire.TxIn{
PreviousOutPoint: wire.OutPoint{
Hash: refTx.TxHash(),
Index: 0,
},
Sequence: testCSVTimeout,
})
spendTx.AddTxOut(txOut)
// Convert it to a PSBT now and add all required signing
// metadata to it.
packet, err := psbt.NewFromUnsignedTx(spendTx)
require.NoError(t, err)
packet.Inputs[0].WitnessScript = witnessScript
packet.Inputs[0].SighashType = txscript.SigHashAll
packet.Inputs[0].WitnessUtxo = refTx.TxOut[0]
packet.Inputs[0].Bip32Derivation = []*psbt.Bip32Derivation{{
PubKey: privKey.PubKey().SerializeCompressed(),
Bip32Path: tc.inputType.keyPath(),
}}
tc.inputType.decorateInput(t, privKey, &packet.Inputs[0])
// Let the wallet do its job. We expect to be the only signer
// for this PSBT, so we'll be able to finalize it later.
err = w.SignPsbt(packet)
require.NoError(t, err)
// If the witness stack needs to be assembled, give the caller
// the option to do that now.
tc.inputType.beforeFinalize(t, packet)
finalTx, err := psbt.Extract(packet)
require.NoError(t, err)
vm, err := txscript.NewEngine(
refTx.TxOut[0].PkScript, finalTx, 0,
txscript.StandardVerifyFlags, nil, nil,
refTx.TxOut[0].Value,
)
require.NoError(t, err)
require.NoError(t, vm.Execute())
}
}