add travis, add go.mod go.sum, update babyjub hex encoders to avoid

importing go-iden3

babyjub/babyjub_test.go

@@ -1,11 +1,11 @@
 package babyjub
 
 import (
-	// "fmt"
 	"encoding/hex"
-	"github.com/stretchr/testify/assert"
 	"math/big"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestAdd1(t *testing.T) {

babyjub/eddsa.go

@@ -2,11 +2,9 @@ package babyjub
 
 import (
 	"crypto/rand"
-	// "encoding/hex"
-	// "fmt"
-	common3 "github.com/iden3/go-iden3/common"
-	"github.com/iden3/go-iden3/crypto/mimc7"
-	// "golang.org/x/crypto/blake2b"
+
+	"github.com/iden3/go-iden3-crypto/mimc7"
+
 	"math/big"
 )
 
@@ -78,17 +76,17 @@ type PublicKey Point
 
 func (pk PublicKey) MarshalText() ([]byte, error) {
 	pkc := pk.Compress()
-	return common3.Hex(pkc[:]).MarshalText()
+	return Hex(pkc[:]).MarshalText()
 }
 
 func (pk PublicKey) String() string {
 	pkc := pk.Compress()
-	return common3.Hex(pkc[:]).String()
+	return Hex(pkc[:]).String()
 }
 
 func (pk *PublicKey) UnmarshalText(h []byte) error {
 	var pkc PublicKeyComp
-	if err := common3.HexDecodeInto(pkc[:], h); err != nil {
+	if err := HexDecodeInto(pkc[:], h); err != nil {
 		return err
 	}
 	pkd, err := pkc.Decompress()
@@ -108,9 +106,9 @@ func (p *PublicKey) Point() *Point {
 // point.
 type PublicKeyComp [32]byte
 
-func (buf PublicKeyComp) MarshalText() ([]byte, error)  { return common3.Hex(buf[:]).MarshalText() }
-func (buf PublicKeyComp) String() string                { return common3.Hex(buf[:]).String() }
-func (buf *PublicKeyComp) UnmarshalText(h []byte) error { return common3.HexDecodeInto(buf[:], h) }
+func (buf PublicKeyComp) MarshalText() ([]byte, error)  { return Hex(buf[:]).MarshalText() }
+func (buf PublicKeyComp) String() string                { return Hex(buf[:]).String() }
+func (buf *PublicKeyComp) UnmarshalText(h []byte) error { return HexDecodeInto(buf[:], h) }
 
 func (p *PublicKey) Compress() PublicKeyComp {
 	return PublicKeyComp((*Point)(p).Compress())
@@ -134,9 +132,9 @@ type Signature struct {
 // SignatureComp represents a compressed EdDSA signature.
 type SignatureComp [64]byte
 
-func (buf SignatureComp) MarshalText() ([]byte, error)  { return common3.Hex(buf[:]).MarshalText() }
-func (buf SignatureComp) String() string                { return common3.Hex(buf[:]).String() }
-func (buf *SignatureComp) UnmarshalText(h []byte) error { return common3.HexDecodeInto(buf[:], h) }
+func (buf SignatureComp) MarshalText() ([]byte, error)  { return Hex(buf[:]).MarshalText() }
+func (buf SignatureComp) String() string                { return Hex(buf[:]).String() }
+func (buf *SignatureComp) UnmarshalText(h []byte) error { return HexDecodeInto(buf[:], h) }
 
 // Compress an EdDSA signature by concatenating the compression of
 // the point R8 and the Little-Endian encoding of S.

babyjub/eddsa_test.go

@@ -7,7 +7,6 @@ import (
 
 	"github.com/stretchr/testify/assert"
 
-	// "golang.org/x/crypto/blake2b"
 	"math/big"
 	"testing"
 )

babyjub/helpers.go

@@ -1,8 +1,13 @@
 package babyjub
 
 import (
-	"github.com/dchest/blake512" // I have personally reviewed that this module doesn't do anything suspicious
+	"bytes"
+	"encoding/hex"
+	"fmt"
 	"math/big"
+	"strings"
+
+	"github.com/dchest/blake512" // I have personally reviewed that this module doesn't do anything suspicious
 )
 
 // SwapEndianness swaps the endianness of the value encoded in xs.  If xs is
@@ -37,3 +42,47 @@ func Blake512(m []byte) []byte {
 	h.Write(m[:])
 	return h.Sum(nil)
 }
+
+// Hex is a byte slice type that can be marshalled and unmarshaled in hex
+type Hex []byte
+
+// MarshalText encodes buf as hex
+func (buf Hex) MarshalText() ([]byte, error) {
+	return []byte(hex.EncodeToString(buf)), nil
+}
+
+// String encodes buf as hex
+func (buf Hex) String() string {
+	return hex.EncodeToString(buf)
+}
+
+// HexEncode encodes an array of bytes into a string in hex.
+func HexEncode(bs []byte) string {
+	return fmt.Sprintf("0x%s", hex.EncodeToString(bs))
+}
+
+// HexDecode decodes a hex string into an array of bytes.
+func HexDecode(h string) ([]byte, error) {
+	if strings.HasPrefix(h, "0x") {
+		h = h[2:]
+	}
+	return hex.DecodeString(h)
+}
+
+// HexDecodeInto decodes a hex string into an array of bytes (dst), verifying
+// that the decoded array has the same length as dst.
+func HexDecodeInto(dst []byte, h []byte) error {
+	if bytes.HasPrefix(h, []byte("0x")) {
+		h = h[2:]
+	}
+	if len(h)/2 != len(dst) {
+		return fmt.Errorf("expected %v bytes in hex string, got %v", len(dst), len(h)/2)
+	}
+	n, err := hex.Decode(dst, h)
+	if err != nil {
+		return err
+	} else if n != len(dst) {
+		return fmt.Errorf("expected %v bytes when decoding hex string, got %v", len(dst), n)
+	}
+	return nil
+}