Beispiel #1
0
// Tests whether a message can be signed, and wrapped in plain-text.
func TestMessageCleartextSignRecover(t *testing.T) {
	key, err := crypto.GenerateKey()
	if err != nil {
		t.Fatalf("failed to create crypto key: %v", err)
	}
	payload := []byte("hello world")

	msg := NewMessage(payload)
	if _, err := msg.Wrap(DefaultPoW, Options{
		From: key,
	}); err != nil {
		t.Fatalf("failed to sign message: %v", err)
	}
	if msg.Flags&signatureFlag != signatureFlag {
		t.Fatalf("signature flag mismatch: have %d, want %d", msg.Flags&signatureFlag, signatureFlag)
	}
	if bytes.Compare(msg.Payload, payload) != 0 {
		t.Fatalf("payload mismatch after signing: have 0x%x, want 0x%x", msg.Payload, payload)
	}

	pubKey := msg.Recover()
	if pubKey == nil {
		t.Fatalf("failed to recover public key")
	}
	p1 := elliptic.Marshal(crypto.S256(), key.PublicKey.X, key.PublicKey.Y)
	p2 := elliptic.Marshal(crypto.S256(), pubKey.X, pubKey.Y)
	if !bytes.Equal(p1, p2) {
		t.Fatalf("public key mismatch: have 0x%x, want 0x%x", p2, p1)
	}
}
Beispiel #2
0
// Tests whether a message can be properly signed and encrypted.
func TestMessageFullCrypto(t *testing.T) {
	fromKey, err := crypto.GenerateKey()
	if err != nil {
		t.Fatalf("failed to create sender crypto key: %v", err)
	}
	toKey, err := crypto.GenerateKey()
	if err != nil {
		t.Fatalf("failed to create recipient crypto key: %v", err)
	}

	payload := []byte("hello world")
	msg := NewMessage(payload)
	envelope, err := msg.Wrap(DefaultPoW, Options{
		From: fromKey,
		To:   &toKey.PublicKey,
	})
	if err != nil {
		t.Fatalf("failed to encrypt message: %v", err)
	}
	if msg.Flags&signatureFlag != signatureFlag {
		t.Fatalf("signature flag mismatch: have %d, want %d", msg.Flags&signatureFlag, signatureFlag)
	}
	if len(msg.Signature) == 0 {
		t.Fatalf("no signature found for signed message")
	}

	out, err := envelope.Open(toKey)
	if err != nil {
		t.Fatalf("failed to open encrypted message: %v", err)
	}
	if !bytes.Equal(out.Payload, payload) {
		t.Error("payload mismatch: have 0x%x, want 0x%x", out.Payload, payload)
	}

	pubKey := out.Recover()
	if pubKey == nil {
		t.Fatalf("failed to recover public key")
	}
	p1 := elliptic.Marshal(crypto.S256(), fromKey.PublicKey.X, fromKey.PublicKey.Y)
	p2 := elliptic.Marshal(crypto.S256(), pubKey.X, pubKey.Y)
	if !bytes.Equal(p1, p2) {
		t.Fatalf("public key mismatch: have 0x%x, want 0x%x", p2, p1)
	}
}
Beispiel #3
0
func decodeAuthMsg(prv *ecdsa.PrivateKey, token []byte, auth []byte) (*encHandshake, error) {
	var err error
	h := new(encHandshake)
	// generate random keypair for session
	h.randomPrivKey, err = ecies.GenerateKey(rand.Reader, crypto.S256(), nil)
	if err != nil {
		return nil, err
	}
	// generate random nonce
	h.respNonce = make([]byte, shaLen)
	if _, err = rand.Read(h.respNonce); err != nil {
		return nil, err
	}

	msg, err := crypto.Decrypt(prv, auth)
	if err != nil {
		return nil, fmt.Errorf("could not decrypt auth message (%v)", err)
	}

	// decode message parameters
	// signature || sha3(ecdhe-random-pubk) || pubk || nonce || token-flag
	h.initNonce = msg[authMsgLen-shaLen-1 : authMsgLen-1]
	copy(h.remoteID[:], msg[sigLen+shaLen:sigLen+shaLen+pubLen])
	rpub, err := h.remoteID.Pubkey()
	if err != nil {
		return nil, fmt.Errorf("bad remoteID: %#v", err)
	}
	h.remotePub = ecies.ImportECDSAPublic(rpub)

	// recover remote random pubkey from signed message.
	if token == nil {
		// TODO: it is an error if the initiator has a token and we don't. check that.

		// no session token means we need to generate shared secret.
		// ecies shared secret is used as initial session token for new peers.
		// generate shared key from prv and remote pubkey.
		if token, err = h.ecdhShared(prv); err != nil {
			return nil, err
		}
	}
	signedMsg := xor(token, h.initNonce)
	remoteRandomPub, err := secp256k1.RecoverPubkey(signedMsg, msg[:sigLen])
	if err != nil {
		return nil, err
	}

	// validate the sha3 of recovered pubkey
	remoteRandomPubMAC := msg[sigLen : sigLen+shaLen]
	shaRemoteRandomPub := crypto.Sha3(remoteRandomPub[1:])
	if !bytes.Equal(remoteRandomPubMAC, shaRemoteRandomPub) {
		return nil, fmt.Errorf("sha3 of recovered ephemeral pubkey does not match checksum in auth message")
	}

	h.remoteRandomPub, _ = importPublicKey(remoteRandomPub)
	return h, nil
}
Beispiel #4
0
// Pubkey returns the public key represented by the node ID.
// It returns an error if the ID is not a point on the curve.
func (id NodeID) Pubkey() (*ecdsa.PublicKey, error) {
	p := &ecdsa.PublicKey{Curve: crypto.S256(), X: new(big.Int), Y: new(big.Int)}
	half := len(id) / 2
	p.X.SetBytes(id[:half])
	p.Y.SetBytes(id[half:])
	if !p.Curve.IsOnCurve(p.X, p.Y) {
		return nil, errors.New("not a point on the S256 curve")
	}
	return p, nil
}
Beispiel #5
0
func newInitiatorHandshake(remoteID discover.NodeID) (*encHandshake, error) {
	rpub, err := remoteID.Pubkey()
	if err != nil {
		return nil, fmt.Errorf("bad remoteID: %v", err)
	}
	// generate random initiator nonce
	n := make([]byte, shaLen)
	if _, err := rand.Read(n); err != nil {
		return nil, err
	}
	// generate random keypair to use for signing
	randpriv, err := ecies.GenerateKey(rand.Reader, crypto.S256(), nil)
	if err != nil {
		return nil, err
	}
	h := &encHandshake{
		initiator:     true,
		remoteID:      remoteID,
		remotePub:     ecies.ImportECDSAPublic(rpub),
		initNonce:     n,
		randomPrivKey: randpriv,
	}
	return h, nil
}