feature(wire/net/simple & backend/sim/wire): change wire implementati…

…on to fit new interface + add tests for authentification

Signed-off-by: Minh Huy Tran <[email protected]>

backend/sim/wire/account.go

@@ -30,6 +30,11 @@ func (acc *Account) Address() wire.Address {
 	return acc.addr
 }
 
+// Sign signs the given message with the account's private key.
+func (acc *Account) Sign(msg []byte) ([]byte, error) {
+	return []byte("Authenticate"), nil
+}
+
 // NewRandomAccount generates a new random account.
 func NewRandomAccount(rng *rand.Rand) *Account {
 	return &Account{

backend/sim/wire/address.go

@@ -16,6 +16,7 @@ package wire
 
 import (
 	"bytes"
+	"errors"
 	"math/rand"
 
 	"perun.network/go-perun/wire"
@@ -62,6 +63,14 @@ func (a Address) Cmp(b wire.Address) int {
 	return bytes.Compare(a[:], bTyped[:])
 }
 
+// Verify verifies a signature.
+func (a Address) Verify(msg, sig []byte) error {
+	if !bytes.Equal(sig, []byte("Authenticate")) {
+		return errors.New("invalid signature")
+	}
+	return nil
+}
+
 // NewRandomAddress returns a new random peer address.
 func NewRandomAddress(rng *rand.Rand) *Address {
 	addr := Address{}

go.mod

@@ -9,14 +9,13 @@ require (
 	go.uber.org/goleak v1.1.11
 	golang.org/x/crypto v0.0.0-20210322153248-0c34fe9e7dc2
 	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c
-	google.golang.org/protobuf v1.23.0
+	google.golang.org/protobuf v1.32.0
 	polycry.pt/poly-go v0.0.0-20220222131629-aa4bdbaab60b
 )
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/golang/snappy v0.0.4 // indirect
-	github.com/google/go-cmp v0.5.4 // indirect
 	github.com/kr/text v0.2.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/stretchr/objx v0.1.1 // indirect

go.sum

@@ -12,13 +12,14 @@ github.com/golang/protobuf v1.4.0-rc.2/go.mod h1:LlEzMj4AhA7rCAGe4KMBDvJI+AwstrU
 github.com/golang/protobuf v1.4.0-rc.4.0.20200313231945-b860323f09d0/go.mod h1:WU3c8KckQ9AFe+yFwt9sWVRKCVIyN9cPHBJSNnbL67w=
 github.com/golang/protobuf v1.4.0/go.mod h1:jodUvKwWbYaEsadDk5Fwe5c77LiNKVO9IDvqG2KuDX0=
 github.com/golang/protobuf v1.4.2/go.mod h1:oDoupMAO8OvCJWAcko0GGGIgR6R6ocIYbsSw735rRwI=
+github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
 github.com/golang/snappy v0.0.4 h1:yAGX7huGHXlcLOEtBnF4w7FQwA26wojNCwOYAEhLjQM=
 github.com/golang/snappy v0.0.4/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
 github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
 github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/google/go-cmp v0.5.4 h1:L8R9j+yAqZuZjsqh/z+F1NCffTKKLShY6zXTItVIZ8M=
-github.com/google/go-cmp v0.5.4/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
+github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pretty v0.2.1 h1:Fmg33tUaq4/8ym9TJN1x7sLJnHVwhP33CNkpYV/7rwI=
@@ -114,8 +115,10 @@ google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ
 google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=
 google.golang.org/protobuf v1.20.1-0.20200309200217-e05f789c0967/go.mod h1:A+miEFZTKqfCUM6K7xSMQL9OKL/b6hQv+e19PK+JZNE=
 google.golang.org/protobuf v1.21.0/go.mod h1:47Nbq4nVaFHyn7ilMalzfO3qCViNmqZ2kzikPIcrTAo=
-google.golang.org/protobuf v1.23.0 h1:4MY060fB1DLGMB/7MBTLnwQUY6+F09GEiz6SsrNqyzM=
 google.golang.org/protobuf v1.23.0/go.mod h1:EGpADcykh3NcUnDUJcl1+ZksZNG86OlYog2l/sGQquU=
+google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
+google.golang.org/protobuf v1.32.0 h1:pPC6BG5ex8PDFnkbrGU3EixyhKcQ2aDuBS36lqK/C7I=
+google.golang.org/protobuf v1.32.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=

wire/net/simple/account.go

@@ -15,31 +15,52 @@
 package simple
 
 import (
+	"crypto"
+	crypto_rand "crypto/rand"
+	"crypto/rsa"
+	"crypto/sha256"
 	"math/rand"
 
+	"github.com/pkg/errors"
 	"perun.network/go-perun/wire"
 )
 
 // Account is a wire account.
 type Account struct {
-	addr wire.Address
-}
-
-// NewAccount creates a new account.
-func NewAccount(addr *Address) *Account {
-	return &Account{
-		addr: addr,
-	}
+	addr       wire.Address
+	privateKey *rsa.PrivateKey
 }
 
 // Address returns the account's address.
 func (acc *Account) Address() wire.Address {
 	return acc.addr
 }
 
+// Sign signs the given message with the account's private key.
+func (acc *Account) Sign(msg []byte) ([]byte, error) {
+	if acc.privateKey == nil {
+		return nil, errors.New("private key is nil")
+	}
+	hashed := sha256.Sum256([]byte(msg))
+	signature, err := rsa.SignPKCS1v15(crypto_rand.Reader, acc.privateKey, crypto.SHA256, hashed[:])
+	if err != nil {
+		return nil, err
+	}
+	return signature, nil
+}
+
 // NewRandomAccount generates a new random account.
 func NewRandomAccount(rng *rand.Rand) *Account {
+	privateKey, err := rsa.GenerateKey(rng, 2048)
+	if err != nil {
+		panic(err)
+	}
+
+	address := NewRandomAddress(rng)
+	address.PublicKey = &privateKey.PublicKey
+
 	return &Account{
-		addr: NewRandomAddress(rng),
+		addr:       address,
+		privateKey: privateKey,
 	}
 }

wire/net/simple/address.go

@@ -16,54 +16,120 @@ package simple
 
 import (
 	"bytes"
+	"crypto"
+	"crypto/rsa"
+	"crypto/sha256"
+	"encoding/binary"
+	"encoding/gob"
 	"math/rand"
 
 	"perun.network/go-perun/wire"
 )
 
 // Address is a wire address.
-type Address string
+type Address struct {
+	Name      string
+	PublicKey *rsa.PublicKey // Public key for verifying signatures
 
-var _ wire.Address = NewAddress("")
+}
+
+var _ wire.Address = (*Address)(nil)
 
 // NewAddress returns a new address.
 func NewAddress(host string) *Address {
-	a := Address(host)
-	return &a
+	return &Address{
+		Name:      host,
+		PublicKey: nil,
+	}
 }
 
 // MarshalBinary marshals the address to binary.
-func (a Address) MarshalBinary() ([]byte, error) {
-	buf := make([]byte, len(a))
-	copy(buf, []byte(a))
-	return buf, nil
+func (a *Address) MarshalBinary() ([]byte, error) {
+	// Initialize a buffer to hold the binary data
+	var buf bytes.Buffer
+
+	// Encode the length of the name string and the name itself
+	nameLen := uint16(len(a.Name))
+	if err := binary.Write(&buf, binary.BigEndian, nameLen); err != nil {
+		return nil, err
+	}
+	if _, err := buf.WriteString(a.Name); err != nil {
+		return nil, err
+	}
+
+	// If the public key is not nil, encode it using gob
+	if a.PublicKey != nil {
+		enc := gob.NewEncoder(&buf)
+		if err := enc.Encode(a.PublicKey); err != nil {
+			return nil, err
+		}
+	}
+
+	// Return the binary representation
+	return buf.Bytes(), nil
 }
 
 // UnmarshalBinary unmarshals an address from binary.
 func (a *Address) UnmarshalBinary(data []byte) error {
-	buf := make([]byte, len(data))
-	copy(buf, data)
-	*a = Address(buf)
+	// Initialize a buffer with the binary data
+	buf := bytes.NewReader(data)
+
+	// Decode the length of the name string
+	var nameLen uint16
+	if err := binary.Read(buf, binary.BigEndian, &nameLen); err != nil {
+		return err
+	}
+
+	// Read the name string from the buffer
+	nameBytes := make([]byte, nameLen)
+	if _, err := buf.Read(nameBytes); err != nil {
+		return err
+	}
+	a.Name = string(nameBytes)
+
+	// If there's remaining data, decode the public key using gob
+	if buf.Len() > 0 {
+		dec := gob.NewDecoder(buf)
+		if err := dec.Decode(&a.PublicKey); err != nil {
+			return err
+		}
+	}
+
 	return nil
 }
 
 // Equal returns whether the two addresses are equal.
-func (a Address) Equal(b wire.Address) bool {
+func (a *Address) Equal(b wire.Address) bool {
 	bTyped, ok := b.(*Address)
 	if !ok {
 		return false
 	}
-	return a == *bTyped
+	if a.PublicKey == nil {
+		return a.Name == bTyped.Name && bTyped.PublicKey == nil
+	}
+
+	return a.Name == bTyped.Name && a.PublicKey.Equal(bTyped.PublicKey)
 }
 
-// Cmp compares the byte representation of two addresses. For `a.Cmp(b)`
-// returns -1 if a < b, 0 if a == b, 1 if a > b.
-func (a Address) Cmp(b wire.Address) int {
+// Cmp compares the byte representation of two addresses.
+func (a *Address) Cmp(b wire.Address) int {
 	bTyped, ok := b.(*Address)
 	if !ok {
 		panic("wrong type")
 	}
-	return bytes.Compare([]byte(a), []byte(*bTyped))
+	if cmp := bytes.Compare([]byte(a.Name), []byte(bTyped.Name)); cmp != 0 {
+		return cmp
+	}
+
+	bytesA, err := a.MarshalBinary()
+	if err != nil {
+		panic(err)
+	}
+	bytesB, err := bTyped.MarshalBinary()
+	if err != nil {
+		panic(err)
+	}
+	return bytes.Compare(bytesA, bytesB)
 }
 
 // NewRandomAddress returns a new random peer address.
@@ -75,6 +141,18 @@ func NewRandomAddress(rng *rand.Rand) *Address {
 		panic(err)
 	}
 
-	a := Address(d)
-	return &a
+	a := &Address{
+		Name: string(d),
+	}
+	return a
+}
+
+// Verify verifies a message signature.
+func (a *Address) Verify(msg []byte, sig []byte) error {
+	hashed := sha256.Sum256(msg)
+	err := rsa.VerifyPKCS1v15(a.PublicKey, crypto.SHA256, hashed[:], sig)
+	if err != nil {
+		return err
+	}
+	return nil
 }