Splited encoding per object type, added public methods for serialization

bson/encoding_privatekey.go

@@ -0,0 +1,79 @@
+// Package bson provides functions for serialization and deserialization between
+// paillier objects and BSON
+package bson
+
+import (
+	"fmt"
+
+	"github.com/keep-network/paillier"
+	"gopkg.in/mgo.v2/bson"
+)
+
+type PrivateKey paillier.PrivateKey
+
+// Serializes PrivateKey to BSON
+func SerializePrivateKey(key *paillier.PrivateKey) ([]byte, error) {
+	return bson.Marshal(toSerializablePrivateKey(key))
+}
+
+// Deserializes BSON to PrivateKey
+func DeserializePrivateKey(data []byte) (*paillier.PrivateKey, error) {
+	serializable := new(PrivateKey)
+	if err := bson.Unmarshal(data, serializable); err != nil {
+		return nil, err
+	}
+
+	return toOriginalPrivateKey(serializable), nil
+}
+
+// Changes original PrivateKey to serializable PrivateKey
+func toSerializablePrivateKey(key *paillier.PrivateKey) *PrivateKey {
+	serializable := PrivateKey(*key)
+	return &serializable
+}
+
+// Changes serializable PrivateKey to original PrivateKey
+func toOriginalPrivateKey(serializable *PrivateKey) *paillier.PrivateKey {
+	original := paillier.PrivateKey(*serializable)
+	return &original
+}
+
+type dbPrivateKey struct {
+	N      string `bson:",omitempty"`
+	Lambda string `bson:",omitempty"`
+	Mu     string `bson:",omitempty"`
+}
+
+func (privateKey *PrivateKey) GetBSON() (interface{}, error) {
+	m := make(map[string]string)
+
+	if privateKey.N != nil {
+		m["n"] = fmt.Sprintf("%x", privateKey.N)
+	}
+	if privateKey.Lambda != nil {
+		m["lambda"] = fmt.Sprintf("%x", privateKey.Lambda)
+	}
+	return m, nil
+}
+
+func (privateKey *PrivateKey) SetBSON(raw bson.Raw) error {
+	var err error = nil
+	c := new(dbPrivateKey)
+	raw.Unmarshal(c)
+
+	if c.N != "" {
+		privateKey.N, err = fromHex(c.N)
+		if err != nil {
+			return err
+		}
+	}
+
+	if c.Lambda != "" {
+		privateKey.Lambda, err = fromHex(c.Lambda)
+		if err != nil {
+			return err
+		}
+	}
+
+	return err
+}