Add ed25519 support

related to fabric pull request #3343,
regarding adding ed25519 support. Since the
bccsp folder was moved to fabric-lib-go,
I am moving the related changes here.

Signed-off-by: Johann Westphall <johannwestphall@gmail.com>

bccsp/opts.go

@@ -22,6 +22,9 @@ const (
 	// ECDSAReRand ECDSA key re-randomization
 	ECDSAReRand = "ECDSA_RERAND"
 
+	// ED25519 Algorithm
+	ED25519 = "ED25519"
+
 	// RSA at the default security level.
 	// Each BCCSP may or may not support default security level. If not supported than
 	// an error will be returned.
@@ -90,6 +93,21 @@ func (opts *ECDSAKeyGenOpts) Ephemeral() bool {
 	return opts.Temporary
 }
 
+type ED25519KeyGenOpts struct {
+	Temporary bool
+}
+
+// Algorithm returns the key generation algorithm identifier (to be used).
+func (opts *ED25519KeyGenOpts) Algorithm() string {
+	return ED25519
+}
+
+// Ephemeral returns true if the key to generate has to be ephemeral,
+// false otherwise.
+func (opts *ED25519KeyGenOpts) Ephemeral() bool {
+	return opts.Temporary
+}
+
 // ECDSAPKIXPublicKeyImportOpts contains options for ECDSA public key importation in PKIX format
 type ECDSAPKIXPublicKeyImportOpts struct {
 	Temporary bool
@@ -139,6 +157,38 @@ func (opts *ECDSAGoPublicKeyImportOpts) Ephemeral() bool {
 	return opts.Temporary
 }
 
+// ED25519PrivateKeyImportOpts contains options for ED25519 key importation from ed25519.PublicKey
+type ED25519PrivateKeyImportOpts struct {
+	Temporary bool
+}
+
+// Algorithm returns the key importation algorithm identifier (to be used).
+func (opts *ED25519PrivateKeyImportOpts) Algorithm() string {
+	return ED25519
+}
+
+// Ephemeral returns true if the key to generate has to be ephemeral,
+// false otherwise.
+func (opts *ED25519PrivateKeyImportOpts) Ephemeral() bool {
+	return opts.Temporary
+}
+
+// ED25519GoPublicKeyImportOpts contains options for ED25519 key importation from ed25519.PublicKey
+type ED25519GoPublicKeyImportOpts struct {
+	Temporary bool
+}
+
+// Algorithm returns the key importation algorithm identifier (to be used).
+func (opts *ED25519GoPublicKeyImportOpts) Algorithm() string {
+	return ED25519
+}
+
+// Ephemeral returns true if the key to generate has to be ephemeral,
+// false otherwise.
+func (opts *ED25519GoPublicKeyImportOpts) Ephemeral() bool {
+	return opts.Temporary
+}
+
 // ECDSAReRandKeyOpts contains options for ECDSA key re-randomization.
 type ECDSAReRandKeyOpts struct {
 	Temporary bool

bccsp/signer/signer.go

@@ -61,9 +61,16 @@ func (s *bccspCryptoSigner) Public() crypto.PublicKey {
 	return s.pk
 }
 
-// Sign signs digest with the private key, possibly using entropy from rand.
+// Sign signs digest or the full message with the private key,
+// possibly using entropy from rand.
 // For an (EC)DSA key, it should be a DER-serialised, ASN.1 signature
-// structure.
+// structure.For an ED25519 key, it should be a signature compatible
+// to the with the RFC 8032.
+//
+// If (EC)DSA signature, the hash must be passed as the "digestOrMsg"
+// parameter. Golang requires the full message to sign with the
+// built-in ED25519 library. Therefore, the full message must be
+// passed as the "digestOrMsg" parameter.
 //
 // Hash implements the SignerOpts interface and, in most cases, one can
 // simply pass in the hash function used as opts. Sign may also attempt
@@ -73,6 +80,6 @@ func (s *bccspCryptoSigner) Public() crypto.PublicKey {
 // Note that when a signature of a hash of a larger message is needed,
 // the caller is responsible for hashing the larger message and passing
 // the hash (as digest) and the hash function (as opts) to Sign.
-func (s *bccspCryptoSigner) Sign(rand io.Reader, digest []byte, opts crypto.SignerOpts) ([]byte, error) {
-	return s.csp.Sign(s.key, digest, opts)
+func (s *bccspCryptoSigner) Sign(rand io.Reader, digestOrMsg []byte, opts crypto.SignerOpts) ([]byte, error) {
+	return s.csp.Sign(s.key, digestOrMsg, opts)
 }

bccsp/sw/ed25519.go

@@ -0,0 +1,40 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+package sw
+
+import (
+	"crypto/ed25519"
+
+	"github.com/hyperledger/fabric-lib-go/bccsp"
+)
+
+func signED25519(k *ed25519.PrivateKey, msg []byte, opts bccsp.SignerOpts) ([]byte, error) {
+	signature := ed25519.Sign(*k, msg)
+	return signature, nil
+}
+
+func verifyED25519(k *ed25519.PublicKey, signature, msg []byte, opts bccsp.SignerOpts) (bool, error) {
+	return ed25519.Verify(*k, msg, signature), nil
+}
+
+type ed25519Signer struct{}
+
+func (s *ed25519Signer) Sign(k bccsp.Key, msg []byte, opts bccsp.SignerOpts) ([]byte, error) {
+	return signED25519(k.(*ed25519PrivateKey).privKey, msg, opts)
+}
+
+type ed25519PrivateKeyVerifier struct{}
+
+func (v *ed25519PrivateKeyVerifier) Verify(k bccsp.Key, signature, msg []byte, opts bccsp.SignerOpts) (bool, error) {
+	castedKey, _ := (k.(*ed25519PrivateKey).privKey.Public()).(ed25519.PublicKey)
+	return verifyED25519(&castedKey, signature, msg, opts)
+}
+
+type ed25519PublicKeyKeyVerifier struct{}
+
+func (v *ed25519PublicKeyKeyVerifier) Verify(k bccsp.Key, signature, msg []byte, opts bccsp.SignerOpts) (bool, error) {
+	return verifyED25519(k.(*ed25519PublicKey).pubKey, signature, msg, opts)
+}

bccsp/sw/ed25519_test.go

@@ -0,0 +1,138 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package sw
+
+import (
+	"crypto/ed25519"
+	"crypto/rand"
+	"crypto/sha256"
+	"crypto/x509"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestVerifyED25519(t *testing.T) {
+	t.Parallel()
+
+	// Generate a key
+	_, lowLevelKey, err := ed25519.GenerateKey(rand.Reader)
+	require.NoError(t, err)
+
+	msg := []byte("hello world")
+	sigma, err := signED25519(&lowLevelKey, msg, nil)
+	require.NoError(t, err)
+
+	castedKey, _ := lowLevelKey.Public().(ed25519.PublicKey)
+	valid, err := verifyED25519(&castedKey, sigma, msg, nil)
+	require.NoError(t, err)
+	require.True(t, valid)
+}
+
+func TestEd25519SignerSign(t *testing.T) {
+	t.Parallel()
+
+	signer := &ed25519Signer{}
+	verifierPrivateKey := &ed25519PrivateKeyVerifier{}
+	verifierPublicKey := &ed25519PublicKeyKeyVerifier{}
+
+	// Generate a key
+	_, lowLevelKey, err := ed25519.GenerateKey(rand.Reader)
+	require.NoError(t, err)
+	k := &ed25519PrivateKey{&lowLevelKey}
+	pk, err := k.PublicKey()
+	require.NoError(t, err)
+
+	// Sign
+	msg := []byte("Hello World")
+	sigma, err := signer.Sign(k, msg, nil)
+	require.NoError(t, err)
+	require.NotNil(t, sigma)
+
+	// Verify
+	castedKey, _ := lowLevelKey.Public().(ed25519.PublicKey)
+	valid, err := verifyED25519(&castedKey, sigma, msg, nil)
+	require.NoError(t, err)
+	require.True(t, valid)
+
+	valid, err = verifierPrivateKey.Verify(k, sigma, msg, nil)
+	require.NoError(t, err)
+	require.True(t, valid)
+
+	valid, err = verifierPublicKey.Verify(pk, sigma, msg, nil)
+	require.NoError(t, err)
+	require.True(t, valid)
+}
+
+func TestEd25519PrivateKey(t *testing.T) {
+	t.Parallel()
+
+	_, lowLevelKey, err := ed25519.GenerateKey(rand.Reader)
+	require.NoError(t, err)
+	k := &ed25519PrivateKey{&lowLevelKey}
+
+	require.False(t, k.Symmetric())
+	require.True(t, k.Private())
+
+	_, err = k.Bytes()
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "Not supported.")
+
+	k.privKey = nil
+	ski := k.SKI()
+	require.Nil(t, ski)
+
+	k.privKey = &lowLevelKey
+	ski = k.SKI()
+	raw := k.privKey.Public().(ed25519.PublicKey)
+	hash := sha256.New()
+	hash.Write(raw)
+	ski2 := hash.Sum(nil)
+	require.Equal(t, ski2, ski, "SKI is not computed in the right way.")
+
+	pk, err := k.PublicKey()
+	require.NoError(t, err)
+	require.NotNil(t, pk)
+	ed25519PK, ok := pk.(*ed25519PublicKey)
+	require.True(t, ok)
+	castedKey, _ := lowLevelKey.Public().(ed25519.PublicKey)
+	require.Equal(t, &castedKey, ed25519PK.pubKey)
+}
+
+func TestEd25519PublicKey(t *testing.T) {
+	t.Parallel()
+
+	_, lowLevelKey, err := ed25519.GenerateKey(rand.Reader)
+	require.NoError(t, err)
+	castedKey, _ := lowLevelKey.Public().(ed25519.PublicKey)
+	k := &ed25519PublicKey{&castedKey}
+
+	require.False(t, k.Symmetric())
+	require.False(t, k.Private())
+
+	k.pubKey = nil
+	ski := k.SKI()
+	require.Nil(t, ski)
+
+	k.pubKey = &castedKey
+	ski = k.SKI()
+	raw := *(k.pubKey)
+	hash := sha256.New()
+	hash.Write(raw)
+	ski2 := hash.Sum(nil)
+	require.Equal(t, ski, ski2, "SKI is not computed in the right way.")
+
+	pk, err := k.PublicKey()
+	require.NoError(t, err)
+	require.Equal(t, k, pk)
+
+	bytes, err := k.Bytes()
+	require.NoError(t, err)
+	bytes2, err := x509.MarshalPKIXPublicKey(*k.pubKey)
+	require.NoError(t, err)
+	require.Equal(t, bytes2, bytes, "bytes are not computed in the right way.")
+}

bccsp/sw/ed25519key.go

@@ -0,0 +1,109 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+package sw
+
+import (
+	"crypto/ed25519"
+	"crypto/sha256"
+	"crypto/x509"
+	"errors"
+	"fmt"
+
+	"github.com/hyperledger/fabric-lib-go/bccsp"
+)
+
+type ed25519PrivateKey struct {
+	privKey *ed25519.PrivateKey
+}
+
+// Bytes converts this key to its byte representation,
+// if this operation is allowed.
+func (k *ed25519PrivateKey) Bytes() ([]byte, error) {
+	return nil, errors.New("Not supported.")
+}
+
+// SKI returns the subject key identifier of this key.
+func (k *ed25519PrivateKey) SKI() []byte {
+	if k.privKey == nil {
+		return nil
+	}
+
+	// Marshall the public key
+	raw := k.privKey.Public().(ed25519.PublicKey)
+
+	// Hash it
+	hash := sha256.New()
+	hash.Write(raw)
+	return hash.Sum(nil)
+}
+
+// Symmetric returns true if this key is a symmetric key,
+// false if this key is asymmetric
+func (k *ed25519PrivateKey) Symmetric() bool {
+	return false
+}
+
+// Private returns true if this key is a private key,
+// false otherwise.
+func (k *ed25519PrivateKey) Private() bool {
+	return true
+}
+
+// PublicKey returns the corresponding public key part of an asymmetric public/private key pair.
+// This method returns an error in symmetric key schemes.
+func (k *ed25519PrivateKey) PublicKey() (bccsp.Key, error) {
+	castedKey, ok := k.privKey.Public().(ed25519.PublicKey)
+	if !ok {
+		return nil, errors.New("Error casting ed25519 public key")
+	}
+	return &ed25519PublicKey{&castedKey}, nil
+}
+
+type ed25519PublicKey struct {
+	pubKey *ed25519.PublicKey
+}
+
+// Bytes converts this key to its byte representation,
+// if this operation is allowed.
+func (k *ed25519PublicKey) Bytes() (raw []byte, err error) {
+	raw, err = x509.MarshalPKIXPublicKey(*k.pubKey)
+	if err != nil {
+		return nil, fmt.Errorf("Failed marshalling key [%s]", err)
+	}
+	return
+}
+
+// SKI returns the subject key identifier of this key.
+func (k *ed25519PublicKey) SKI() []byte {
+	if k.pubKey == nil {
+		return nil
+	}
+
+	raw := *(k.pubKey)
+
+	// Hash it
+	hash := sha256.New()
+	hash.Write(raw)
+	return hash.Sum(nil)
+}
+
+// Symmetric returns true if this key is a symmetric key,
+// false if this key is asymmetric
+func (k *ed25519PublicKey) Symmetric() bool {
+	return false
+}
+
+// Private returns true if this key is a private key,
+// false otherwise.
+func (k *ed25519PublicKey) Private() bool {
+	return false
+}
+
+// PublicKey returns the corresponding public key part of an asymmetric public/private key pair.
+// This method returns an error in symmetric key schemes.
+func (k *ed25519PublicKey) PublicKey() (bccsp.Key, error) {
+	return k, nil
+}