BCCSP-based crypto.Signer

This change-set introduced a crypto.Signer implementation based on BCCSP.
This is needed to be able to sign x509 certificates using the BCCSP.
This change-set comes in the context of:
https://jira.hyperledger.org/browse/FAB-354

Change-Id: I3adaf716bd513f6447f0d65c23ec71b06d5dcdda
Signed-off-by: Angelo De Caro <[email protected]>

Author: adecaro

core/crypto/bccsp/signer/signer.go

@@ -0,0 +1,103 @@
+/*
+Copyright IBM Corp. 2016 All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+		 http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package signer
+
+import (
+	"crypto"
+	"errors"
+	"fmt"
+	"io"
+
+	"github.com/hyperledger/fabric/core/crypto/bccsp"
+	"github.com/hyperledger/fabric/core/crypto/primitives"
+)
+
+// CryptoSigner is the BCCSP-based implementation of a crypto.Signer
+type CryptoSigner struct {
+	csp bccsp.BCCSP
+	key bccsp.Key
+	pk  interface{}
+}
+
+// Init initializes this CryptoSigner.
+func (s *CryptoSigner) Init(csp bccsp.BCCSP, key bccsp.Key) error {
+	// Validate arguments
+	if csp == nil {
+		return errors.New("Invalid BCCSP. Nil.")
+	}
+	if key == nil {
+		return errors.New("Invalid Key. Nil.")
+	}
+	if key.Symmetric() {
+		return errors.New("Invalid Key. Symmetric.")
+	}
+
+	// Marshall the bccsp public key as a crypto.PublicKey
+	pub, err := key.PublicKey()
+	if err != nil {
+		return fmt.Errorf("Failed getting public key [%s]", err)
+	}
+
+	raw, err := pub.Bytes()
+	if err != nil {
+		return fmt.Errorf("Failed marshalling public key [%s]", err)
+	}
+
+	pk, err := primitives.DERToPublicKey(raw)
+	if err != nil {
+		return fmt.Errorf("Failed marshalling public key [%s]", err)
+	}
+
+	// Init fields
+	s.csp = csp
+	s.key = key
+	s.pk = pk
+
+	return nil
+
+}
+
+// Public returns the public key corresponding to the opaque,
+// private key.
+func (s *CryptoSigner) Public() crypto.PublicKey {
+	return s.pk
+}
+
+// Sign signs digest with the private key, possibly using entropy from
+// rand. For an RSA key, the resulting signature should be either a
+// PKCS#1 v1.5 or PSS signature (as indicated by opts). For an (EC)DSA
+// key, it should be a DER-serialised, ASN.1 signature structure.
+//
+// Hash implements the SignerOpts interface and, in most cases, one can
+// simply pass in the hash function used as opts. Sign may also attempt
+// to type assert opts to other types in order to obtain algorithm
+// specific values. See the documentation in each package for details.
+//
+// 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 *CryptoSigner) Sign(rand io.Reader, digest []byte, opts crypto.SignerOpts) (signature []byte, err error) {
+	if opts == nil {
+		return s.csp.Sign(s.key, digest, nil)
+	}
+
+	so, ok := opts.(bccsp.SignerOpts)
+	if !ok {
+		return nil, errors.New("Invalid opts type. Expecting bccsp.SignerOpts")
+	}
+
+	return s.csp.Sign(s.key, digest, so)
+}

core/crypto/bccsp/signer/signer_test.go

@@ -0,0 +1,110 @@
+/*
+Copyright IBM Corp. 2016 All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+		 http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package signer
+
+import (
+	"crypto/rand"
+	"os"
+	"testing"
+
+	"github.com/hyperledger/fabric/core/crypto/bccsp"
+	"github.com/hyperledger/fabric/core/crypto/bccsp/sw"
+	"github.com/hyperledger/fabric/core/crypto/primitives"
+	"github.com/spf13/viper"
+)
+
+var (
+	swBCCSPInstance bccsp.BCCSP
+)
+
+func getBCCSP(t *testing.T) bccsp.BCCSP {
+	if swBCCSPInstance == nil {
+		primitives.InitSecurityLevel("SHA2", 256)
+		viper.Set("security.bccsp.default.keyStorePath", os.TempDir())
+
+		var err error
+		swBCCSPInstance, err = sw.New()
+		if err != nil {
+			t.Fatalf("Failed initializing key store [%s]", err)
+		}
+	}
+
+	return swBCCSPInstance
+}
+
+func TestInit(t *testing.T) {
+	csp := getBCCSP(t)
+
+	k, err := csp.KeyGen(&bccsp.ECDSAKeyGenOpts{Temporary: true})
+	if err != nil {
+		t.Fatalf("Failed generating ECDSA key [%s]", err)
+	}
+
+	signer := &CryptoSigner{}
+	err = signer.Init(csp, k)
+	if err != nil {
+		t.Fatalf("Failed initializing CryptoSigner [%s]", err)
+	}
+}
+
+func TestPublic(t *testing.T) {
+	csp := getBCCSP(t)
+
+	k, err := csp.KeyGen(&bccsp.ECDSAKeyGenOpts{Temporary: true})
+	if err != nil {
+		t.Fatalf("Failed generating ECDSA key [%s]", err)
+	}
+
+	signer := &CryptoSigner{}
+	err = signer.Init(csp, k)
+	if err != nil {
+		t.Fatalf("Failed initializing CryptoSigner [%s]", err)
+	}
+
+	pk := signer.Public()
+	if pk == nil {
+		t.Fatal("Failed getting PublicKey. Nil.")
+	}
+}
+
+func TestSign(t *testing.T) {
+	csp := getBCCSP(t)
+
+	k, err := csp.KeyGen(&bccsp.ECDSAKeyGenOpts{Temporary: true})
+	if err != nil {
+		t.Fatalf("Failed generating ECDSA key [%s]", err)
+	}
+
+	signer := &CryptoSigner{}
+	err = signer.Init(csp, k)
+	if err != nil {
+		t.Fatalf("Failed initializing CryptoSigner [%s]", err)
+	}
+
+	msg := []byte("Hello World")
+	signature, err := signer.Sign(rand.Reader, primitives.Hash(msg), nil)
+	if err != nil {
+		t.Fatalf("Failed generating ECDSA signature [%s]", err)
+	}
+
+	valid, err := csp.Verify(k, signature, primitives.Hash(msg))
+	if err != nil {
+		t.Fatalf("Failed verifying ECDSA signature [%s]", err)
+	}
+	if !valid {
+		t.Fatal("Failed verifying ECDSA signature. Signature not valid.")
+	}
+}