Forfeit transactions: signing process (#81)

* sign forfeit transactions

* revert txid + move SignVtxos func

* Fix nolint

* Fix

* fix connectorsToInputArgs function

---------

Co-authored-by: altafan <18440657+altafan@users.noreply.github.com>

asp/go.mod

@@ -5,7 +5,7 @@ go 1.21.0
 replace github.com/ark-network/ark/common => ../common
 
 require (
-	github.com/ark-network/ark/common v0.0.0-00010101000000-000000000000
+	github.com/ark-network/ark/common v0.0.0
 	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0
 	github.com/dgraph-io/badger/v4 v4.1.0
 	github.com/go-co-op/gocron v1.36.0
@@ -18,7 +18,7 @@ require (
 	github.com/stretchr/testify v1.8.4
 	github.com/timshannon/badgerhold/v4 v4.0.3
 	github.com/urfave/cli/v2 v2.26.0
-	github.com/vulpemventures/go-elements v0.5.1
+	github.com/vulpemventures/go-elements v0.5.2
 	google.golang.org/genproto/googleapis/api v0.0.0-20231106174013-bbf56f31fb17
 	google.golang.org/grpc v1.59.0
 	google.golang.org/protobuf v1.31.0

asp/go.sum

@@ -327,8 +327,8 @@ github.com/urfave/cli/v2 v2.26.0 h1:3f3AMg3HpThFNT4I++TKOejZO8yU55t3JnnSr4S4QEI=
 github.com/urfave/cli/v2 v2.26.0/go.mod h1:8qnjx1vcq5s2/wpsqoZFndg2CE5tNFyrTvS6SinrnYQ=
 github.com/vulpemventures/fastsha256 v0.0.0-20160815193821-637e65642941 h1:CTcw80hz/Sw8hqlKX5ZYvBUF5gAHSHwdjXxRf/cjDcI=
 github.com/vulpemventures/fastsha256 v0.0.0-20160815193821-637e65642941/go.mod h1:GXBJykxW2kUcktGdsgyay7uwwWvkljASfljNcT0mbh8=
-github.com/vulpemventures/go-elements v0.5.1 h1:F83n7dScOnAnpyH9VgWLdC68Qcva+2EWVzzNuW2UKak=
-github.com/vulpemventures/go-elements v0.5.1/go.mod h1:aBGuWXHaiAIUIcwqCdtEh2iQ3kJjKwHU9ywvhlcRSeU=
+github.com/vulpemventures/go-elements v0.5.2 h1:vIDzVpRXG5PnlzHA8tCnr2Tn7raIV5cHy7bRyDrbuM4=
+github.com/vulpemventures/go-elements v0.5.2/go.mod h1:aBGuWXHaiAIUIcwqCdtEh2iQ3kJjKwHU9ywvhlcRSeU=
 github.com/vulpemventures/go-secp256k1-zkp v1.1.6 h1:BmsrmXRLUibwa75Qkk8yELjpzCzlAjYFGLiLiOdq7Xo=
 github.com/vulpemventures/go-secp256k1-zkp v1.1.6/go.mod h1:zo7CpgkuPgoe7fAV+inyxsI9IhGmcoFgyD8nqZaPSOM=
 github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77/go.mod h1:aYKd//L2LvnjZzWKhF00oedf4jCCReLcmhLdhm1A27Q=

asp/internal/core/application/service.go

@@ -10,6 +10,7 @@ import (
 	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/internal/core/domain"
 	"github.com/ark-network/ark/internal/core/ports"
+	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/decred/dcrd/dcrec/secp256k1/v4"
 	log "github.com/sirupsen/logrus"
 	"github.com/vulpemventures/go-elements/network"
@@ -62,7 +63,9 @@ func NewService(
 ) (Service, error) {
 	eventsCh := make(chan domain.RoundEvent)
 	paymentRequests := newPaymentsMap(nil)
-	forfeitTxs := newForfeitTxsMap()
+
+	genesisHash, _ := chainhash.NewHashFromStr(onchainNetwork.GenesisBlockHash)
+	forfeitTxs := newForfeitTxsMap(genesisHash)
 	pubkey, err := walletSvc.GetPubkey(context.Background())
 	if err != nil {
 		return nil, fmt.Errorf("failed to fetch pubkey: %s", err)
@@ -169,10 +172,7 @@ func (s *service) FaucetVtxos(ctx context.Context, userPubkey *secp256k1.PublicK
 }
 
 func (s *service) SignVtxos(ctx context.Context, forfeitTxs []string) error {
-	if err := s.forfeitTxs.sign(forfeitTxs); err != nil {
-		return fmt.Errorf("invalid forfeit tx: %s", err)
-	}
-	return nil
+	return s.forfeitTxs.sign(forfeitTxs)
 }
 
 func (s *service) ListVtxos(ctx context.Context, pubkey *secp256k1.PublicKey) ([]domain.Vtxo, error) {

asp/internal/core/application/utils.go

@@ -1,12 +1,17 @@
 package application
 
 import (
+	"bytes"
+	"encoding/hex"
 	"fmt"
 	"sort"
 	"sync"
 	"time"
 
+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/internal/core/domain"
+	"github.com/btcsuite/btcd/btcec/v2/schnorr"
+	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/vulpemventures/go-elements/psetv2"
 )
 
@@ -136,22 +141,36 @@ type signedTx struct {
 }
 
 type forfeitTxsMap struct {
-	lock       *sync.RWMutex
-	forfeitTxs map[string]*signedTx
+	lock             *sync.RWMutex
+	forfeitTxs       map[string]*signedTx
+	genesisBlockHash *chainhash.Hash
 }
 
-func newForfeitTxsMap() *forfeitTxsMap {
-	return &forfeitTxsMap{&sync.RWMutex{}, make(map[string]*signedTx)}
+func newForfeitTxsMap(genesisBlockHash *chainhash.Hash) *forfeitTxsMap {
+	return &forfeitTxsMap{&sync.RWMutex{}, make(map[string]*signedTx), genesisBlockHash}
 }
 
 func (m *forfeitTxsMap) push(txs []string) {
 	m.lock.Lock()
 	defer m.lock.Unlock()
 
+	faucetTxID, _ := hex.DecodeString(faucetVtxo.Txid)
+
 	for _, tx := range txs {
 		ptx, _ := psetv2.NewPsetFromBase64(tx)
 		utx, _ := ptx.UnsignedTx()
-		m.forfeitTxs[utx.TxHash().String()] = &signedTx{tx, false}
+
+		signed := false
+
+		// find the faucet vtxos, and mark them as signed
+		for _, input := range ptx.Inputs {
+			if bytes.Equal(input.PreviousTxid, faucetTxID) {
+				signed = true
+				break
+			}
+		}
+
+		m.forfeitTxs[utx.TxHash().String()] = &signedTx{tx, signed}
 	}
 }
 
@@ -160,17 +179,50 @@ func (m *forfeitTxsMap) sign(txs []string) error {
 	defer m.lock.Unlock()
 
 	for _, tx := range txs {
-		ptx, err := psetv2.NewPsetFromBase64(tx)
-		if err != nil {
-			return fmt.Errorf("invalid forfeit tx format")
-		}
+		ptx, _ := psetv2.NewPsetFromBase64(tx)
 		utx, _ := ptx.UnsignedTx()
 		txid := utx.TxHash().String()
-		if _, ok := m.forfeitTxs[txid]; !ok {
-			return fmt.Errorf("forfeit tx %s not found", txid)
+
+		if _, ok := m.forfeitTxs[txid]; ok {
+			for index, input := range ptx.Inputs {
+				if len(input.TapScriptSig) > 0 {
+					for _, tapScriptSig := range input.TapScriptSig {
+						leafHash, err := chainhash.NewHash(tapScriptSig.LeafHash)
+						if err != nil {
+							return err
+						}
+
+						preimage, err := common.TaprootPreimage(
+							m.genesisBlockHash,
+							ptx,
+							index,
+							leafHash,
+						)
+						if err != nil {
+							return err
+						}
+
+						sig, err := schnorr.ParseSignature(tapScriptSig.Signature)
+						if err != nil {
+							return err
+						}
+
+						pubkey, err := schnorr.ParsePubKey(tapScriptSig.PubKey)
+						if err != nil {
+							return err
+						}
+
+						if sig.Verify(preimage, pubkey) {
+							m.forfeitTxs[txid].signed = true
+						} else {
+							return fmt.Errorf("invalid signature")
+						}
+					}
+				}
+			}
 		}
-		m.forfeitTxs[txid].signed = true
 	}
+
 	return nil
 }
 

asp/internal/infrastructure/tx-builder/covenant/builder.go

@@ -4,10 +4,12 @@ import (
 	"context"
 	"encoding/hex"
 
+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/internal/core/domain"
 	"github.com/ark-network/ark/internal/core/ports"
 	"github.com/decred/dcrd/dcrec/secp256k1/v4"
 	"github.com/vulpemventures/go-elements/address"
+	"github.com/vulpemventures/go-elements/elementsutil"
 	"github.com/vulpemventures/go-elements/network"
 	"github.com/vulpemventures/go-elements/payment"
 	"github.com/vulpemventures/go-elements/psetv2"
@@ -58,29 +60,11 @@ func getTxid(txStr string) (string, error) {
 }
 
 func (b *txBuilder) GetLeafOutputScript(userPubkey, aspPubkey *secp256k1.PublicKey) ([]byte, error) {
-	unspendableKeyBytes, _ := hex.DecodeString(unspendablePoint)
-	unspendableKey, _ := secp256k1.ParsePubKey(unspendableKeyBytes)
-
-	sweepTaprootLeaf, err := sweepTapLeaf(aspPubkey)
+	outputScript, _, err := b.getLeafTaprootTree(userPubkey, aspPubkey)
 	if err != nil {
 		return nil, err
 	}
-
-	leafScript, err := checksigScript(userPubkey)
-	if err != nil {
-		return nil, err
-	}
-
-	leafTaprootLeaf := taproot.NewBaseTapElementsLeaf(leafScript)
-	leafTaprootTree := taproot.AssembleTaprootScriptTree(leafTaprootLeaf, *sweepTaprootLeaf)
-	root := leafTaprootTree.RootNode.TapHash()
-
-	taprootKey := taproot.ComputeTaprootOutputKey(
-		unspendableKey,
-		root[:],
-	)
-
-	return taprootOutputScript(taprootKey)
+	return outputScript, nil
 }
 
 // BuildForfeitTxs implements ports.TxBuilder.
@@ -119,17 +103,46 @@ func (b *txBuilder) BuildForfeitTxs(
 		return nil, nil, err
 	}
 
+	lbtc, _ := elementsutil.AssetHashToBytes(b.net.AssetID)
+
 	forfeitTxs = make([]string, 0)
+
 	for _, payment := range payments {
 		for _, vtxo := range payment.Inputs {
+			vtxoAmount, err := elementsutil.ValueToBytes(vtxo.Amount)
+			if err != nil {
+				return nil, nil, err
+			}
+
+			pubkeyBytes, err := hex.DecodeString(vtxo.Pubkey)
+			if err != nil {
+				return nil, nil, err
+			}
+
+			vtxoPubkey, err := secp256k1.ParsePubKey(pubkeyBytes)
+			if err != nil {
+				return nil, nil, err
+			}
+
+			vtxoOutputScript, vtxoTaprootTree, err := b.getLeafTaprootTree(vtxoPubkey, aspPubkey)
+			if err != nil {
+				return nil, nil, err
+			}
+
 			for _, connector := range connectorsAsInputs {
 				forfeitTx, err := createForfeitTx(
-					connector,
+					connector.input,
+					connector.witnessUtxo,
 					psetv2.InputArgs{
 						Txid:    vtxo.Txid,
 						TxIndex: vtxo.VOut,
 					},
-					vtxo.Amount,
+					&transaction.TxOutput{
+						Asset:  lbtc,
+						Value:  vtxoAmount,
+						Script: vtxoOutputScript,
+					},
+					vtxoTaprootTree,
 					aspScript,
 					*b.net,
 				)
@@ -140,6 +153,7 @@ func (b *txBuilder) BuildForfeitTxs(
 				forfeitTxs = append(forfeitTxs, forfeitTx)
 			}
 		}
+
 	}
 
 	return connectors, forfeitTxs, nil
@@ -211,45 +225,79 @@ func (b *txBuilder) BuildPoolTx(
 	return
 }
 
-func connectorsToInputArgs(connectors []string) ([]psetv2.InputArgs, error) {
-	inputs := make([]psetv2.InputArgs, 0, len(connectors)+1)
+func (b *txBuilder) getLeafTaprootTree(userPubkey, aspPubkey *secp256k1.PublicKey) ([]byte, *taproot.IndexedElementsTapScriptTree, error) {
+	sweepTaprootLeaf, err := sweepTapLeaf(aspPubkey)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	vtxoLeaf, err := common.VtxoScript(userPubkey)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	leafTaprootTree := taproot.AssembleTaprootScriptTree(*vtxoLeaf, *sweepTaprootLeaf)
+	root := leafTaprootTree.RootNode.TapHash()
+
+	unspendableKeyBytes, _ := hex.DecodeString(unspendablePoint)
+	unspendableKey, _ := secp256k1.ParsePubKey(unspendableKeyBytes)
+
+	taprootKey := taproot.ComputeTaprootOutputKey(
+		unspendableKey,
+		root[:],
+	)
+
+	outputScript, err := taprootOutputScript(taprootKey)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return outputScript, leafTaprootTree, nil
+}
+
+type inputWithWitnessUtxo struct {
+	input       psetv2.InputArgs
+	witnessUtxo *transaction.TxOutput
+}
+
+func connectorsToInputArgs(connectors []string) ([]inputWithWitnessUtxo, error) {
+	inputs := make([]inputWithWitnessUtxo, 0, len(connectors)+1)
 	for i, psetb64 := range connectors {
-		txID, err := getTxID(psetb64)
+		pset, err := psetv2.NewPsetFromBase64(psetb64)
 		if err != nil {
 			return nil, err
 		}
 
+		utx, err := pset.UnsignedTx()
+		if err != nil {
+			return nil, err
+		}
+
+		txID := utx.TxHash().String()
+
 		input := psetv2.InputArgs{
 			Txid:    txID,
 			TxIndex: 0,
 		}
-		inputs = append(inputs, input)
+		inputs = append(inputs, inputWithWitnessUtxo{
+			input:       input,
+			witnessUtxo: utx.Outputs[0],
+		})
 
-		if i == len(connectors)-1 {
+		if i == len(connectors)-1 && len(utx.Outputs) > 1 {
 			input := psetv2.InputArgs{
 				Txid:    txID,
 				TxIndex: 1,
 			}
-			inputs = append(inputs, input)
+			inputs = append(inputs, inputWithWitnessUtxo{
+				input:       input,
+				witnessUtxo: utx.Outputs[1],
+			})
 		}
 	}
 	return inputs, nil
 }
 
-func getTxID(psetBase64 string) (string, error) {
-	pset, err := psetv2.NewPsetFromBase64(psetBase64)
-	if err != nil {
-		return "", err
-	}
-
-	utx, err := pset.UnsignedTx()
-	if err != nil {
-		return "", err
-	}
-
-	return utx.TxHash().String(), nil
-}
-
 func numberOfVTXOs(payments []domain.Payment) uint64 {
 	var sum uint64
 	for _, payment := range payments {

asp/internal/infrastructure/tx-builder/covenant/builder_test.go

@@ -300,14 +300,14 @@ func TestBuildCongestionTree(t *testing.T) {
 func TestBuildForfeitTxs(t *testing.T) {
 	builder := txbuilder.NewTxBuilder(network.Liquid)
 
-	// TODO
-	poolTx, err := createTestPoolTx(1000, 2)
+	// TODO: replace with fixture.
+	poolTxHex, err := createTestPoolTx(1000, 2)
 	require.NoError(t, err)
 
-	tx, err := transaction.NewTxFromHex(poolTx)
+	poolTx, err := transaction.NewTxFromHex(poolTxHex)
 	require.NoError(t, err)
 
-	poolTxID := tx.TxHash().String()
+	poolTxid := poolTx.TxHash().String()
 
 	fixtures := []struct {
 		payments                []domain.Payment
@@ -363,7 +363,7 @@ func TestBuildForfeitTxs(t *testing.T) {
 
 	for _, f := range fixtures {
 		connectors, forfeitTxs, err := builder.BuildForfeitTxs(
-			key, poolTx, f.payments,
+			key, poolTxHex, f.payments,
 		)
 		require.NoError(t, err)
 		require.Len(t, connectors, f.expectedNumOfConnectors)
@@ -381,7 +381,7 @@ func TestBuildForfeitTxs(t *testing.T) {
 			require.Len(t, pset.Inputs, 1)
 			require.Len(t, pset.Outputs, 2)
 
-			expectedInputTxid := poolTxID
+			expectedInputTxid := poolTxid
 			expectedInputVout := uint32(1)
 			if i > 0 {
 				tx, err := connectorsPsets[i-1].UnsignedTx()
@@ -406,7 +406,7 @@ func TestBuildForfeitTxs(t *testing.T) {
 		// each forfeit tx should have 2 inputs and 2 outputs
 		for _, pset := range forfeitTxsPsets {
 			require.Len(t, pset.Inputs, 2)
-			require.Len(t, pset.Outputs, 1)
+			require.Len(t, pset.Outputs, 2)
 		}
 	}
 }

asp/internal/infrastructure/tx-builder/covenant/forfeit.go

@@ -1,14 +1,23 @@
 package txbuilder
 
 import (
+	"encoding/hex"
+
+	"github.com/btcsuite/btcd/txscript"
+	"github.com/decred/dcrd/dcrec/secp256k1/v4"
+	"github.com/vulpemventures/go-elements/elementsutil"
 	"github.com/vulpemventures/go-elements/network"
 	"github.com/vulpemventures/go-elements/psetv2"
+	"github.com/vulpemventures/go-elements/taproot"
+	"github.com/vulpemventures/go-elements/transaction"
 )
 
 func createForfeitTx(
 	connectorInput psetv2.InputArgs,
+	connectorWitnessUtxo *transaction.TxOutput,
 	vtxoInput psetv2.InputArgs,
-	vtxoAmount uint64,
+	vtxoWitnessUtxo *transaction.TxOutput,
+	vtxoTaprootTree *taproot.IndexedElementsTapScriptTree,
 	aspScript []byte,
 	net network.Network,
 ) (forfeitTx string, err error) {
@@ -22,7 +31,42 @@ func createForfeitTx(
 		return "", err
 	}
 
-	err = updater.AddInputs([]psetv2.InputArgs{connectorInput, vtxoInput})
+	if err = updater.AddInputs([]psetv2.InputArgs{connectorInput, vtxoInput}); err != nil {
+		return "", err
+	}
+
+	if err = updater.AddInWitnessUtxo(0, connectorWitnessUtxo); err != nil {
+		return "", err
+	}
+
+	if err := updater.AddInSighashType(0, txscript.SigHashAll); err != nil {
+		return "", err
+	}
+
+	if err = updater.AddInWitnessUtxo(1, vtxoWitnessUtxo); err != nil {
+		return "", err
+	}
+
+	if err := updater.AddInSighashType(1, txscript.SigHashDefault); err != nil {
+		return "", err
+	}
+
+	unspendableKeyBytes, _ := hex.DecodeString(unspendablePoint)
+	unspendableKey, _ := secp256k1.ParsePubKey(unspendableKeyBytes)
+
+	for _, proof := range vtxoTaprootTree.LeafMerkleProofs {
+		tapScript := psetv2.NewTapLeafScript(proof, unspendableKey)
+		if err := updater.AddInTapLeafScript(1, tapScript); err != nil {
+			return "", err
+		}
+	}
+
+	vtxoAmount, err := elementsutil.ValueFromBytes(vtxoWitnessUtxo.Value)
+	if err != nil {
+		return "", err
+	}
+
+	connectorAmount, err := elementsutil.ValueFromBytes(connectorWitnessUtxo.Value)
 	if err != nil {
 		return "", err
 	}
@@ -30,9 +74,13 @@ func createForfeitTx(
 	err = updater.AddOutputs([]psetv2.OutputArgs{
 		{
 			Asset:  net.AssetID,
-			Amount: vtxoAmount,
+			Amount: vtxoAmount + connectorAmount - 30,
 			Script: aspScript,
 		},
+		{
+			Asset:  net.AssetID,
+			Amount: 30,
+		},
 	})
 	if err != nil {
 		return "", err

asp/internal/interface/grpc/handlers/utils.go

@@ -18,7 +18,7 @@ func parseTxs(txs []string) ([]string, error) {
 	}
 	for _, tx := range txs {
 		if _, err := psetv2.NewPsetFromBase64(tx); err != nil {
-			return nil, fmt.Errorf("invalid tx format")
+			return nil, fmt.Errorf("invalid tx format %s", err)
 		}
 	}
 	return txs, nil

common/go.mod

@@ -6,14 +6,16 @@ require (
 	github.com/btcsuite/btcd v0.23.1
 	github.com/btcsuite/btcd/btcec/v2 v2.3.2
 	github.com/btcsuite/btcd/btcutil v1.1.3
+	github.com/btcsuite/btcd/chaincfg/chainhash v1.0.1
 	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0
 	github.com/stretchr/testify v1.8.0
 )
 
 require (
-	github.com/btcsuite/btcd/chaincfg/chainhash v1.0.1 // indirect
+	github.com/btcsuite/btcd/btcutil/psbt v1.1.4 // indirect
 	github.com/btcsuite/btclog v0.0.0-20170628155309-84c8d2346e9f // indirect
 	github.com/decred/dcrd/crypto/blake256 v1.0.1 // indirect
+	github.com/vulpemventures/fastsha256 v0.0.0-20160815193821-637e65642941 // indirect
 	golang.org/x/crypto v0.0.0-20220525230936-793ad666bf5e // indirect
 	golang.org/x/sys v0.0.0-20220608164250-635b8c9b7f68 // indirect
 )
@@ -21,6 +23,6 @@ require (
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/vulpemventures/go-elements v0.5.1
+	github.com/vulpemventures/go-elements v0.5.2
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

common/go.sum

@@ -76,8 +76,8 @@ github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO
 github.com/syndtr/goleveldb v1.0.1-0.20210819022825-2ae1ddf74ef7/go.mod h1:q4W45IWZaF22tdD+VEXcAWRA037jwmWEB5VWYORlTpc=
 github.com/vulpemventures/fastsha256 v0.0.0-20160815193821-637e65642941 h1:CTcw80hz/Sw8hqlKX5ZYvBUF5gAHSHwdjXxRf/cjDcI=
 github.com/vulpemventures/fastsha256 v0.0.0-20160815193821-637e65642941/go.mod h1:GXBJykxW2kUcktGdsgyay7uwwWvkljASfljNcT0mbh8=
-github.com/vulpemventures/go-elements v0.5.1 h1:F83n7dScOnAnpyH9VgWLdC68Qcva+2EWVzzNuW2UKak=
-github.com/vulpemventures/go-elements v0.5.1/go.mod h1:aBGuWXHaiAIUIcwqCdtEh2iQ3kJjKwHU9ywvhlcRSeU=
+github.com/vulpemventures/go-elements v0.5.2 h1:vIDzVpRXG5PnlzHA8tCnr2Tn7raIV5cHy7bRyDrbuM4=
+github.com/vulpemventures/go-elements v0.5.2/go.mod h1:aBGuWXHaiAIUIcwqCdtEh2iQ3kJjKwHU9ywvhlcRSeU=
 github.com/vulpemventures/go-secp256k1-zkp v1.1.6 h1:BmsrmXRLUibwa75Qkk8yELjpzCzlAjYFGLiLiOdq7Xo=
 github.com/vulpemventures/go-secp256k1-zkp v1.1.6/go.mod h1:zo7CpgkuPgoe7fAV+inyxsI9IhGmcoFgyD8nqZaPSOM=
 golang.org/x/crypto v0.0.0-20170930174604-9419663f5a44/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=

common/taproot.go

@@ -0,0 +1,48 @@
+package common
+
+import (
+	"fmt"
+
+	"github.com/btcsuite/btcd/chaincfg/chainhash"
+	"github.com/vulpemventures/go-elements/psetv2"
+)
+
+// TaprootPreimage computes the hash for witness v1 input of a pset
+// it implicitly assumes that the pset has witnessUtxo fields populated
+func TaprootPreimage(
+	genesisBlockHash *chainhash.Hash,
+	pset *psetv2.Pset,
+	inputIndex int,
+	leafHash *chainhash.Hash,
+) ([]byte, error) {
+	prevoutScripts := make([][]byte, 0)
+	prevoutAssets := make([][]byte, 0)
+	prevoutValues := make([][]byte, 0)
+
+	for i, input := range pset.Inputs {
+		if input.WitnessUtxo == nil {
+			return nil, fmt.Errorf("missing witness utxo on input #%d", i)
+		}
+
+		prevoutScripts = append(prevoutScripts, input.WitnessUtxo.Script)
+		prevoutAssets = append(prevoutAssets, input.WitnessUtxo.Asset)
+		prevoutValues = append(prevoutValues, input.WitnessUtxo.Value)
+	}
+
+	utx, err := pset.UnsignedTx()
+	if err != nil {
+		return nil, err
+	}
+
+	preimage := utx.HashForWitnessV1(
+		inputIndex,
+		prevoutScripts,
+		prevoutAssets,
+		prevoutValues,
+		pset.Inputs[inputIndex].SigHashType,
+		genesisBlockHash,
+		leafHash,
+		nil,
+	)
+	return preimage[:], nil
+}

noah/common.go

@@ -9,13 +9,16 @@ import (
 	"io"
 	"net/http"
 	"syscall"
+	"time"
 
 	arkv1 "github.com/ark-network/ark/api-spec/protobuf/gen/ark/v1"
 	"github.com/ark-network/ark/common"
+	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/decred/dcrd/dcrec/secp256k1/v4"
 	"github.com/urfave/cli/v2"
 	"github.com/vulpemventures/go-elements/network"
 	"github.com/vulpemventures/go-elements/payment"
+	"github.com/vulpemventures/go-elements/psetv2"
 	"golang.org/x/term"
 )
 
@@ -85,6 +88,7 @@ func privateKeyFromPassword() (*secp256k1.PrivateKey, error) {
 	if err != nil {
 		return nil, err
 	}
+	fmt.Println("key unlocked")
 
 	cypher := NewAES128Cypher()
 	privateKeyBytes, err := cypher.Decrypt(encryptedPrivateKey, password)
@@ -333,3 +337,125 @@ func printJSON(resp interface{}) error {
 	fmt.Println(string(jsonBytes))
 	return nil
 }
+
+func handleRoundStream(
+	ctx *cli.Context,
+	client arkv1.ArkServiceClient,
+	paymentID string,
+	vtxosToSign []vtxo,
+	secKey *secp256k1.PrivateKey,
+) (poolTxID string, err error) {
+	stream, err := client.GetEventStream(ctx.Context, &arkv1.GetEventStreamRequest{})
+	if err != nil {
+		return "", err
+	}
+
+	var pingStop func()
+	pingReq := &arkv1.PingRequest{
+		PaymentId: paymentID,
+	}
+	for pingStop == nil {
+		pingStop = ping(ctx, client, pingReq)
+	}
+
+	defer pingStop()
+
+	for {
+		event, err := stream.Recv()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return "", err
+		}
+
+		if event.GetRoundFailed() != nil {
+			pingStop()
+			return "", fmt.Errorf("round failed: %s", event.GetRoundFailed().GetReason())
+		}
+
+		if event.GetRoundFinalization() != nil {
+			// stop pinging as soon as we receive some forfeit txs
+			pingStop()
+			forfeits := event.GetRoundFinalization().GetForfeitTxs()
+			signedForfeits := make([]string, 0)
+
+			fmt.Println("signing forfeit txs...")
+
+			explorer := NewExplorer()
+
+			for _, forfeit := range forfeits {
+				pset, err := psetv2.NewPsetFromBase64(forfeit)
+				if err != nil {
+					return "", err
+				}
+
+				for _, input := range pset.Inputs {
+					inputTxid := chainhash.Hash(input.PreviousTxid).String()
+
+					for _, coin := range vtxosToSign {
+						// check if it contains one of the input to sign
+						if inputTxid == coin.txid {
+							if err := signPset(pset, explorer, secKey); err != nil {
+								return "", err
+							}
+
+							signedPset, err := pset.ToBase64()
+							if err != nil {
+								return "", err
+							}
+
+							signedForfeits = append(signedForfeits, signedPset)
+						}
+					}
+				}
+			}
+
+			// if no forfeit txs have been signed, start pinging again and wait for the next round
+			if len(signedForfeits) == 0 {
+				fmt.Println("no forfeit txs to sign, waiting for the next round...")
+				pingStop = nil
+				for pingStop == nil {
+					pingStop = ping(ctx, client, pingReq)
+				}
+				continue
+			}
+
+			fmt.Printf("%d forfeit txs signed, finalizing payment...\n", len(signedForfeits))
+			_, err = client.FinalizePayment(ctx.Context, &arkv1.FinalizePaymentRequest{
+				SignedForfeitTxs: signedForfeits,
+			})
+			if err != nil {
+				return "", err
+			}
+
+			continue
+		}
+
+		if event.GetRoundFinalized() != nil {
+			return event.GetRoundFinalized().GetPoolTxid(), nil
+		}
+	}
+
+	return "", fmt.Errorf("stream closed unexpectedly")
+}
+
+// send 1 ping message every 5 seconds to signal to the ark service that we are still alive
+// returns a function that can be used to stop the pinging
+func ping(ctx *cli.Context, client arkv1.ArkServiceClient, req *arkv1.PingRequest) func() {
+	_, err := client.Ping(ctx.Context, req)
+	if err != nil {
+		return nil
+	}
+
+	ticker := time.NewTicker(5 * time.Second)
+
+	go func(t *time.Ticker) {
+		for range t.C {
+			// nolint
+			client.Ping(ctx.Context, req)
+		}
+	}(ticker)
+
+	return ticker.Stop
+}

noah/go.mod

@@ -8,7 +8,7 @@ replace github.com/ark-network/ark => ../asp
 
 require (
 	github.com/ark-network/ark v0.0.0-00010101000000-000000000000
-	github.com/ark-network/ark/common v0.0.0-00010101000000-000000000000
+	github.com/ark-network/ark/common v0.0.0
 	github.com/btcsuite/btcd v0.23.4
 	github.com/btcsuite/btcd/btcec/v2 v2.3.2
 	github.com/btcsuite/btcd/chaincfg/chainhash v1.0.3
@@ -31,7 +31,7 @@ require (
 	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.18.1 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
-	github.com/vulpemventures/go-elements v0.5.1
+	github.com/vulpemventures/go-elements v0.5.2
 	github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 // indirect
 	golang.org/x/net v0.19.0 // indirect
 	golang.org/x/sys v0.15.0 // indirect

noah/go.sum

@@ -82,8 +82,6 @@ github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 h1:Jamvg5psRI
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
-github.com/savsgio/gotils v0.0.0-20230208104028-c358bd845dee h1:8Iv5m6xEo1NR1AvpV+7XmhI4r39LGNzwUL4YpMuL5vk=
-github.com/savsgio/gotils v0.0.0-20230208104028-c358bd845dee/go.mod h1:qwtSXrKuJh/zsFQ12yEE89xfCrGKK63Rr7ctU/uCo4g=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
@@ -93,8 +91,8 @@ github.com/urfave/cli/v2 v2.26.0 h1:3f3AMg3HpThFNT4I++TKOejZO8yU55t3JnnSr4S4QEI=
 github.com/urfave/cli/v2 v2.26.0/go.mod h1:8qnjx1vcq5s2/wpsqoZFndg2CE5tNFyrTvS6SinrnYQ=
 github.com/vulpemventures/fastsha256 v0.0.0-20160815193821-637e65642941 h1:CTcw80hz/Sw8hqlKX5ZYvBUF5gAHSHwdjXxRf/cjDcI=
 github.com/vulpemventures/fastsha256 v0.0.0-20160815193821-637e65642941/go.mod h1:GXBJykxW2kUcktGdsgyay7uwwWvkljASfljNcT0mbh8=
-github.com/vulpemventures/go-elements v0.5.1 h1:F83n7dScOnAnpyH9VgWLdC68Qcva+2EWVzzNuW2UKak=
-github.com/vulpemventures/go-elements v0.5.1/go.mod h1:aBGuWXHaiAIUIcwqCdtEh2iQ3kJjKwHU9ywvhlcRSeU=
+github.com/vulpemventures/go-elements v0.5.2 h1:vIDzVpRXG5PnlzHA8tCnr2Tn7raIV5cHy7bRyDrbuM4=
+github.com/vulpemventures/go-elements v0.5.2/go.mod h1:aBGuWXHaiAIUIcwqCdtEh2iQ3kJjKwHU9ywvhlcRSeU=
 github.com/vulpemventures/go-secp256k1-zkp v1.1.6 h1:BmsrmXRLUibwa75Qkk8yELjpzCzlAjYFGLiLiOdq7Xo=
 github.com/vulpemventures/go-secp256k1-zkp v1.1.6/go.mod h1:zo7CpgkuPgoe7fAV+inyxsI9IhGmcoFgyD8nqZaPSOM=
 github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 h1:bAn7/zixMGCfxrRTfdpNzjtPYqr8smhKouy9mxVdGPU=

noah/redeem.go

@@ -3,7 +3,6 @@ package main
 import (
 	"bufio"
 	"fmt"
-	"io"
 	"log"
 	"math"
 	"os"
@@ -11,7 +10,6 @@ import (
 	"time"
 
 	arkv1 "github.com/ark-network/ark/api-spec/protobuf/gen/ark/v1"
-	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/urfave/cli/v2"
 	"github.com/vulpemventures/go-elements/address"
 	"github.com/vulpemventures/go-elements/psetv2"
@@ -132,6 +130,11 @@ func collaborativeRedeem(ctx *cli.Context, addr string, amount uint64) error {
 		})
 	}
 
+	secKey, err := privateKeyFromPassword()
+	if err != nil {
+		return err
+	}
+
 	registerResponse, err := client.RegisterPayment(ctx.Context, &arkv1.RegisterPaymentRequest{
 		Inputs: inputs,
 	})
@@ -147,81 +150,21 @@ func collaborativeRedeem(ctx *cli.Context, addr string, amount uint64) error {
 		return err
 	}
 
-	stream, err := client.GetEventStream(ctx.Context, &arkv1.GetEventStreamRequest{})
+	poolTxID, err := handleRoundStream(
+		ctx,
+		client,
+		registerResponse.GetId(),
+		selectedCoins,
+		secKey,
+	)
 	if err != nil {
 		return err
 	}
 
-	var pingStop func()
-	pingReq := &arkv1.PingRequest{
-		PaymentId: registerResponse.GetId(),
-	}
-	for pingStop == nil {
-		pingStop = ping(ctx, client, pingReq)
-	}
-
-	for {
-		event, err := stream.Recv()
-		if err == io.EOF {
-			break
-		}
-		if err != nil {
-			return err
-		}
-
-		if event.GetRoundFailed() != nil {
-			return fmt.Errorf("round failed: %s", event.GetRoundFailed().GetReason())
-		}
-
-		if event.GetRoundFinalization() != nil {
-			// stop pinging as soon as we receive some forfeit txs
-			pingStop()
-			forfeits := event.GetRoundFinalization().GetForfeitTxs()
-			signedForfeits := make([]string, 0)
-
-			for _, forfeit := range forfeits {
-				pset, err := psetv2.NewPsetFromBase64(forfeit)
-				if err != nil {
-					return err
-				}
-
-				// check if it contains one of the input to sign
-				for _, input := range pset.Inputs {
-					inputTxid := chainhash.Hash(input.PreviousTxid).String()
-
-					for _, coin := range selectedCoins {
-						if inputTxid == coin.txid {
-							// TODO: sign the vtxo input
-							signedForfeits = append(signedForfeits, forfeit)
-						}
-					}
-				}
-			}
-
-			// if no forfeit txs have been signed, start pinging again and wait for the next round
-			if len(signedForfeits) == 0 {
-				pingStop = nil
-				for pingStop == nil {
-					pingStop = ping(ctx, client, pingReq)
-				}
-				continue
-			}
-
-			_, err := client.FinalizePayment(ctx.Context, &arkv1.FinalizePaymentRequest{
-				SignedForfeitTxs: signedForfeits,
-			})
-			if err != nil {
-				return err
-			}
-
-			continue
-		}
-
-		if event.GetRoundFinalized() != nil {
-			return printJSON(map[string]interface{}{
-				"pool_txid": event.GetRoundFinalized().GetPoolTxid(),
-			})
-		}
+	if err := printJSON(map[string]interface{}{
+		"pool_txid": poolTxID,
+	}); err != nil {
+		return err
 	}
 
 	return nil

noah/send.go

@@ -4,14 +4,10 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
-	"io"
-	"time"
 
 	arkv1 "github.com/ark-network/ark/api-spec/protobuf/gen/ark/v1"
 	"github.com/ark-network/ark/common"
-	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/urfave/cli/v2"
-	"github.com/vulpemventures/go-elements/psetv2"
 )
 
 type receiver struct {
@@ -133,6 +129,11 @@ func sendAction(ctx *cli.Context) error {
 		})
 	}
 
+	secKey, err := privateKeyFromPassword()
+	if err != nil {
+		return err
+	}
+
 	registerResponse, err := client.RegisterPayment(ctx.Context, &arkv1.RegisterPaymentRequest{
 		Inputs: inputs,
 	})
@@ -148,102 +149,22 @@ func sendAction(ctx *cli.Context) error {
 		return err
 	}
 
-	stream, err := client.GetEventStream(ctx.Context, &arkv1.GetEventStreamRequest{})
+	poolTxID, err := handleRoundStream(
+		ctx,
+		client,
+		registerResponse.GetId(),
+		selectedCoins,
+		secKey,
+	)
 	if err != nil {
 		return err
 	}
 
-	var pingStop func()
-	pingReq := &arkv1.PingRequest{
-		PaymentId: registerResponse.GetId(),
-	}
-	for pingStop == nil {
-		pingStop = ping(ctx, client, pingReq)
-	}
-
-	for {
-		event, err := stream.Recv()
-		if err == io.EOF {
-			break
-		}
-		if err != nil {
-			return err
-		}
-
-		if event.GetRoundFailed() != nil {
-			return fmt.Errorf("round failed: %s", event.GetRoundFailed().GetReason())
-		}
-
-		if event.GetRoundFinalization() != nil {
-			// stop pinging as soon as we receive some forfeit txs
-			pingStop()
-			forfeits := event.GetRoundFinalization().GetForfeitTxs()
-			signedForfeits := make([]string, 0)
-
-			for _, forfeit := range forfeits {
-				pset, err := psetv2.NewPsetFromBase64(forfeit)
-				if err != nil {
-					return err
-				}
-
-				// check if it contains one of the input to sign
-				for _, input := range pset.Inputs {
-					inputTxid := chainhash.Hash(input.PreviousTxid).String()
-
-					for _, coin := range selectedCoins {
-						if inputTxid == coin.txid {
-							// TODO: sign the vtxo input
-							signedForfeits = append(signedForfeits, forfeit)
-						}
-					}
-				}
-			}
-
-			// if no forfeit txs have been signed, start pinging again and wait for the next round
-			if len(signedForfeits) == 0 {
-				pingStop = nil
-				for pingStop == nil {
-					pingStop = ping(ctx, client, pingReq)
-				}
-				continue
-			}
-
-			_, err := client.FinalizePayment(ctx.Context, &arkv1.FinalizePaymentRequest{
-				SignedForfeitTxs: signedForfeits,
-			})
-			if err != nil {
-				return err
-			}
-
-			continue
-		}
-
-		if event.GetRoundFinalized() != nil {
-			return printJSON(map[string]interface{}{
-				"pool_txid": event.GetRoundFinalized().GetPoolTxid(),
-			})
-		}
+	if err := printJSON(map[string]interface{}{
+		"pool_txid": poolTxID,
+	}); err != nil {
+		return err
 	}
 
 	return nil
 }
-
-// send 1 ping message every 5 seconds to signal to the ark service that we are still alive
-// returns a function that can be used to stop the pinging
-func ping(ctx *cli.Context, client arkv1.ArkServiceClient, req *arkv1.PingRequest) func() {
-	_, err := client.Ping(ctx.Context, req)
-	if err != nil {
-		return nil
-	}
-
-	ticker := time.NewTicker(5 * time.Second)
-
-	go func(t *time.Ticker) {
-		for range t.C {
-			// nolint
-			client.Ping(ctx.Context, req)
-		}
-	}(ticker)
-
-	return ticker.Stop
-}

noah/signer.go

@@ -125,10 +125,7 @@ func signPset(
 			continue
 		}
 
-		pubkey, err := getWalletPublicKey()
-		if err != nil {
-			return err
-		}
+		pubkey := prvKey.PubKey()
 
 		vtxoLeaf, err := common.VtxoScript(pubkey)
 		if err != nil {
@@ -174,8 +171,6 @@ func signPset(
 					if err := signer.SignTaprootInputTapscriptSig(i, tapScriptSig); err != nil {
 						return err
 					}
-
-					continue
 				}
 			}
 		}