Merge pull request lightningnetwork#17 from cfromknecht/obfuscator-se…

…rialization

Obfuscator Serialization

obfuscation.go

@@ -69,6 +69,18 @@ func (o *OnionErrorEncrypter) EncryptError(initial bool, data []byte) []byte {
 	return onionEncrypt(o.sharedSecret, data)
 }
 
+// Encode writes the encrypter's shared secret to the provided io.Writer.
+func (o *OnionErrorEncrypter) Encode(w io.Writer) error {
+	_, err := w.Write(o.sharedSecret[:])
+	return err
+}
+
+// Decode restores the encrypter's share secret from the provided io.Reader.
+func (o *OnionErrorEncrypter) Decode(r io.Reader) error {
+	_, err := io.ReadFull(r, o.sharedSecret[:])
+	return err
+}
+
 // Circuit is used encapsulate the data which is needed for data deobfuscation.
 type Circuit struct {
 	// SessionKey is the key which have been used during generation of the

obfuscation_test.go

@@ -3,6 +3,7 @@ package sphinx
 import (
 	"bytes"
 	"encoding/hex"
+	"reflect"
 	"testing"
 
 	"github.com/roasbeef/btcd/btcec"
@@ -201,6 +202,21 @@ func TestOnionFailureSpecVector(t *testing.T) {
 			sharedSecret: sharedSecrets[len(sharedSecrets)-1-i],
 		}
 
+		var b bytes.Buffer
+		if err := obfuscator.Encode(&b); err != nil {
+			t.Fatalf("unable to encode obfuscator: %v", err)
+		}
+
+		obfuscator2 := &OnionErrorEncrypter{}
+		obfuscatorReader := bytes.NewReader(b.Bytes())
+		if err := obfuscator2.Decode(obfuscatorReader); err != nil {
+			t.Fatalf("unable to decode obfuscator: %v", err)
+		}
+
+		if !reflect.DeepEqual(obfuscator, obfuscator2) {
+			t.Fatalf("unable to reconstruct obfuscator: %v", err)
+		}
+
 		if !bytes.Equal(expectedSharedSecret, obfuscator.sharedSecret[:]) {
 			t.Fatalf("shared secret not match with spec: expected "+
 				"%x, got %x", expectedSharedSecret,