Channel

channel/backend.go

@@ -0,0 +1,54 @@
+package channel
+
+import (
+	"crypto/sha256"
+	"perun.network/go-perun/channel"
+	"perun.network/go-perun/wallet"
+	"perun.network/perun-stellar-backend/channel/types"
+	"perun.network/perun-stellar-backend/wire"
+)
+
+type backend struct{}
+
+var Backend = backend{}
+
+func init() {
+	channel.SetBackend(Backend)
+}
+
+func (b backend) CalcID(params *channel.Params) channel.ID {
+	wp := wire.MustMakeParams(*params)
+	bytes, err := wp.MarshalBinary()
+	if err != nil {
+		panic(err)
+	}
+	return sha256.Sum256(bytes)
+}
+
+func (b backend) Sign(account wallet.Account, state *channel.State) (wallet.Sig, error) {
+	bytes, err := EncodeState(state)
+	if err != nil {
+		return nil, err
+	}
+	return account.SignData(bytes)
+}
+
+func (b backend) Verify(addr wallet.Address, state *channel.State, sig wallet.Sig) (bool, error) {
+	bytes, err := EncodeState(state)
+	if err != nil {
+		return false, err
+	}
+	return wallet.VerifySignature(bytes, sig, addr)
+}
+
+func (b backend) NewAsset() channel.Asset {
+	return &types.StellarAsset{}
+}
+
+func EncodeState(state *channel.State) ([]byte, error) {
+	ws, err := wire.MakeState(*state)
+	if err != nil {
+		return nil, err
+	}
+	return ws.MarshalBinary()
+}

channel/test/init.go

@@ -0,0 +1,7 @@
+package test
+
+import "perun.network/go-perun/channel/test"
+
+func init() {
+	test.SetRandomizer(&Randomizer{})
+}

channel/test/randomizer.go

@@ -0,0 +1,23 @@
+package test
+
+import (
+	"github.com/stellar/go/xdr"
+	"math/rand"
+	"perun.network/go-perun/channel"
+	"perun.network/go-perun/channel/test"
+	"perun.network/perun-stellar-backend/channel/types"
+)
+
+type Randomizer struct{}
+
+var _ test.Randomizer = (*Randomizer)(nil)
+
+func (*Randomizer) NewRandomAsset(*rand.Rand) channel.Asset {
+	return NewRandomStellarAsset()
+}
+
+func NewRandomStellarAsset() *types.StellarAsset {
+	var contractID xdr.Hash
+	rand.Read(contractID[:])
+	return types.NewStellarAsset(contractID)
+}

channel/types/asset.go

@@ -0,0 +1,108 @@
+package types
+
+import (
+	"errors"
+	"github.com/stellar/go/keypair"
+	"github.com/stellar/go/xdr"
+	"perun.network/go-perun/channel"
+)
+
+const HashLenXdr = 32
+
+type StellarAsset struct {
+	contractID xdr.Hash
+}
+
+func (s StellarAsset) ContractID() xdr.Hash {
+	return s.contractID
+}
+
+func NewStellarAsset(contractID xdr.Hash) *StellarAsset {
+	return &StellarAsset{contractID: contractID}
+}
+
+func (s StellarAsset) MarshalBinary() (data []byte, err error) {
+	return s.contractID.MarshalBinary()
+}
+
+func (s *StellarAsset) UnmarshalBinary(data []byte) error {
+	var addr [HashLenXdr]byte
+	copy(addr[:], data)
+	err := s.contractID.UnmarshalBinary(data)
+	if err != nil {
+		return errors.New("could not unmarshal contract id")
+	}
+	return nil
+}
+
+func (s StellarAsset) Equal(asset channel.Asset) bool {
+	_, ok := asset.(*StellarAsset)
+	return ok
+}
+
+func (s StellarAsset) MakeScAddress() (xdr.ScAddress, error) {
+	hash := s.contractID
+	scvAddr, err := MakeContractAddress(hash)
+	if err != nil {
+		return xdr.ScAddress{}, errors.New("could not generate contract address")
+	}
+	return scvAddr, nil
+}
+
+func (s *StellarAsset) FromScAddress(address xdr.ScAddress) error {
+	addrType := address.Type
+	if addrType != xdr.ScAddressTypeScAddressTypeContract {
+		return errors.New("invalid address type")
+	}
+
+	s.contractID = *address.ContractId
+	return nil
+}
+
+func NewStellarAssetFromScAddress(address xdr.ScAddress) (*StellarAsset, error) {
+	s := &StellarAsset{}
+	err := s.FromScAddress(address)
+	if err != nil {
+		return nil, err
+	}
+	return s, nil
+}
+
+func MustStellarAsset(asset channel.Asset) *StellarAsset {
+	p, ok := asset.(*StellarAsset)
+	if !ok {
+		panic("Asset has invalid type")
+	}
+	return p
+}
+
+func ToStellarAsset(asset channel.Asset) (*StellarAsset, error) {
+	p, ok := asset.(*StellarAsset)
+	if !ok {
+		return nil, errors.New("asset has invalid type")
+	}
+	return p, nil
+}
+
+func MakeAccountAddress(kp keypair.KP) (xdr.ScAddress, error) {
+	accountId, err := xdr.AddressToAccountId(kp.Address())
+	if err != nil {
+		return xdr.ScAddress{}, err
+	}
+	return xdr.NewScAddress(xdr.ScAddressTypeScAddressTypeAccount, accountId)
+}
+
+func MakeContractAddress(contractID xdr.Hash) (xdr.ScAddress, error) {
+	return xdr.NewScAddress(xdr.ScAddressTypeScAddressTypeContract, contractID)
+}
+
+func ToAccountAddress(address xdr.ScAddress) (keypair.FromAddress, error) {
+	if address.Type != xdr.ScAddressTypeScAddressTypeAccount {
+		return keypair.FromAddress{}, errors.New("invalid address type")
+	}
+	kp, err := keypair.ParseAddress(address.AccountId.Address())
+	if err != nil {
+		return keypair.FromAddress{}, err
+	}
+	return *kp, nil
+}

channel/types/asset_test.go

@@ -0,0 +1,35 @@
+package types_test
+
+import (
+	"github.com/stellar/go/keypair"
+	"github.com/stellar/go/xdr"
+	"github.com/stretchr/testify/require"
+	"perun.network/perun-stellar-backend/channel/types"
+
+	"testing"
+)
+
+func TestMarshalAndUnmarshalBinary(t *testing.T) {
+	var hash xdr.Hash
+	copy(hash[:], []byte("testhashfortestingonly!testhash"))
+
+	asset := types.NewStellarAsset(hash)
+
+	data, err := asset.MarshalBinary()
+	require.NoError(t, err)
+
+	newAsset := &types.StellarAsset{}
+	err = newAsset.UnmarshalBinary(data)
+	require.NoError(t, err)
+
+	require.Equal(t, asset.ContractID().HexString(), newAsset.ContractID().HexString(), "Mismatched ContractID. Expected %x, got %x", asset.ContractID(), newAsset.ContractID())
+}
+
+func TestMakeAccountAddress(t *testing.T) {
+	kp, _ := keypair.Random()
+
+	address, err := types.MakeAccountAddress(kp)
+	require.NoError(t, err)
+
+	require.Equal(t, xdr.ScAddressTypeScAddressTypeAccount, address.Type, "Expected account address type, got %v", address.Type)
+}

go.mod

@@ -2,18 +2,19 @@ module perun.network/perun-stellar-backend
 
 go 1.19
 
-require github.com/stellar/go v0.0.0-20230718034032-95c2976a11f2
+require github.com/stellar/go v0.0.0-20230905170723-6e18a2f2f583
 
 require (
-	github.com/stretchr/testify v1.7.0
+	github.com/stellar/go-xdr v0.0.0-20211103144802-8017fc4bdfee
+	github.com/stretchr/testify v1.8.1
 	perun.network/go-perun v0.10.6
 	polycry.pt/poly-go v0.0.0-20220222131629-aa4bdbaab60b
 )
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/kr/pretty v0.3.1 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/stellar/go-xdr v0.0.0-20211103144802-8017fc4bdfee // indirect
-	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -1,33 +1,44 @@
+github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/hpcloud/tail v1.0.0 h1:nfCOvKYfkgYP8hkirhJocXT2+zOD8yUNjXaWfTlyFKI=
-github.com/kr/pretty v0.2.0 h1:s5hAObm+yFO5uHYt5dYjxi2rXrsnmRpJx4OYvIWUaQs=
+github.com/fsnotify/fsnotify v1.6.0 h1:n+5WquG0fcWoWp6xPWfHdbskMCQaFnG6PfBrh1Ky4HY=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
+github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
-github.com/onsi/ginkgo v1.7.0 h1:WSHQ+IS43OoUrWtD1/bbclrwK8TTH5hzp+umCiuxHgs=
-github.com/onsi/gomega v1.4.3 h1:RE1xgDvH7imwFD45h+u2SgIfERHlS2yNG4DObb5BSKU=
+github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/nxadm/tail v1.4.8 h1:nPr65rt6Y5JFSKQO7qToXr7pePgD6Gwiw05lkbyAQTE=
+github.com/onsi/ginkgo v1.16.5 h1:8xi0RTUf59SOSfEtZMvwTvXYMzG4gV23XVHOZiXNtnE=
+github.com/onsi/gomega v1.27.10 h1:naR28SdDFlqrG6kScpT8VWpu1xWY5nJRCF3XaYyBjhI=
+github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/stellar/go v0.0.0-20230718034032-95c2976a11f2 h1:puur8PRJFs+o3CFEUf5FF/w3kOVAd1bvK9PU9jr3ouA=
-github.com/stellar/go v0.0.0-20230718034032-95c2976a11f2/go.mod h1:iTkyf5zUHlaIjZjyxaLLXLv+YHqg3etsqn8AOQ+DvG8=
+github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
+github.com/rogpeppe/go-internal v1.11.0 h1:cWPaGQEPrBb5/AsnsZesgZZ9yb1OQ+GOISoDNXVBh4M=
+github.com/stellar/go v0.0.0-20230905170723-6e18a2f2f583 h1:oC7naR8IBqtWV/b+G91gTOe+jR52+GpkXhCxEyYawYY=
+github.com/stellar/go v0.0.0-20230905170723-6e18a2f2f583/go.mod h1:5/qoLl0pexA5OPi0BZvDsOc3532CJlHuRg1dnBxbsGg=
 github.com/stellar/go-xdr v0.0.0-20211103144802-8017fc4bdfee h1:fbVs0xmXpBvVS4GBeiRmAE3Le70ofAqFMch1GTiq/e8=
 github.com/stellar/go-xdr v0.0.0-20211103144802-8017fc4bdfee/go.mod h1:yoxyU/M8nl9LKeWIoBrbDPQ7Cy+4jxRcWcOayZ4BMps=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
-github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
+github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 github.com/xdrpp/goxdr v0.1.1 h1:E1B2c6E8eYhOVyd7yEpOyopzTPirUeF6mVOfXfGyJyc=
-golang.org/x/net v0.0.0-20220722155237-a158d28d115b h1:PxfKdU9lEEDYjdIzOtC4qFWgkU2rGHdKlKowJSMN9h0=
-golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f h1:v4INt8xihDGvnrfjMDVXGxw9wrfxYyCjk0KbXjhR55s=
-golang.org/x/text v0.3.8 h1:nAL+RVCQ9uMn3vJZbV+MRnydTJFPf8qqY42YiA6MrqY=
+golang.org/x/net v0.14.0 h1:BONx9s002vGdD9umnlX1Po8vOZmrgH34qlHcD1MfK14=
+golang.org/x/sys v0.11.0 h1:eG7RXZHdqOJ1i+0lgLgCpSXAp6M3LYlAo6osgSi0xOM=
+golang.org/x/text v0.12.0 h1:k+n5B8goJNdU7hSvEtMUz3d1Q6D/XW4COJSJR6fN0mc=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
-gopkg.in/fsnotify.v1 v1.4.7 h1:xOHLXZwVvI9hhs+cLKq5+I5onOuwQLhQwiu63xxlHs4=
 gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 h1:uRGJdciOHaEIrze2W8Q3AKkepLTh2hOroT7a+7czfdQ=
-gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 perun.network/go-perun v0.10.6 h1:uj1e33yfCSfE75DK/uwjNp+TwvGG85Qhi6HuYQ9EPrQ=
 perun.network/go-perun v0.10.6/go.mod h1:BGBZC3npkX457u87pjDd0NEIXr1a4dsH4H/YpLdGGe8=
 polycry.pt/poly-go v0.0.0-20220222131629-aa4bdbaab60b h1:BJsSrLQ3kLRNYXNqly//IYeXlVmAhpI5wYbg2WD1wR0=

wallet/account.go

@@ -6,6 +6,7 @@ import (
 	"github.com/stellar/go/keypair"
 	"math/rand"
 	"perun.network/go-perun/wallet"
+	"perun.network/perun-stellar-backend/wallet/types"
 )
 
 // Account is used for signing channel state.
@@ -40,9 +41,28 @@ func NewRandomAccount(rng *rand.Rand) (*Account, *keypair.Full, error) {
 	return acc, kp, nil
 }
 
+func NewRandomAddress(rng *rand.Rand) wallet.Address {
+	kp, err := keypair.Random()
+	if err != nil {
+		panic(err)
+	}
+	acc, err := NewRandomAccountWithAddress(rng, kp.FromAddress())
+	if err != nil {
+		panic(err)
+	}
+
+	addr := acc.Address()
+
+	return addr
+}
+
 // Address returns the Participant this account belongs to.
 func (a Account) Address() wallet.Address {
-	return NewParticipant(a.ParticipantAddress, a.privateKey.Public().(ed25519.PublicKey))
+	return types.NewParticipant(a.ParticipantAddress, a.privateKey.Public().(ed25519.PublicKey))
+}
+
+func (a Account) Participant() *types.Participant {
+	return types.NewParticipant(a.ParticipantAddress, a.privateKey.Public().(ed25519.PublicKey))
 }
 
 // SignData signs the given data with the account's private key.

wallet/backend.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"io"
 	"perun.network/go-perun/wallet"
+	"perun.network/perun-stellar-backend/wallet/types"
 )
 
 // SignatureLength is the length of a signature in bytes.
@@ -19,7 +20,7 @@ func init() {
 }
 
 func (b backend) NewAddress() wallet.Address {
-	return &Participant{}
+	return &types.Participant{}
 }
 
 // DecodeSig decodes a signature of length SignatureLength from the reader.
@@ -32,7 +33,7 @@ func (b backend) DecodeSig(reader io.Reader) (wallet.Sig, error) {
 }
 
 func (b backend) VerifySignature(msg []byte, sig wallet.Sig, a wallet.Address) (bool, error) {
-	p, ok := a.(*Participant)
+	p, ok := a.(*types.Participant)
 	if !ok {
 		return false, errors.New("Participant has invalid type")
 	}

wallet/test/init.go

@@ -0,0 +1,10 @@
+package test
+
+import (
+	"perun.network/go-perun/wallet/test"
+	_ "perun.network/perun-stellar-backend/channel/test"
+)
+
+func init() {
+	test.SetRandomizer(&Randomizer{})
+}