Golang curve25519.ScalarBaseMult函數代碼示例

func TestStreamData(t *testing.T) {
	var serverPrivate, clientPrivate, serverPublic, clientPublic [32]byte

	randBytes(serverPrivate[:])
	randBytes(clientPrivate[:])
	curve25519.ScalarBaseMult(&serverPublic, &serverPrivate)
	curve25519.ScalarBaseMult(&clientPublic, &clientPrivate)

	x, y := NewBiDiPipe()
	client := NewClient(x, &clientPrivate, &clientPublic, &serverPublic)
	server := NewServer(y, &serverPrivate)

	clientComplete := make(chan bool)
	go func() {
		defer x.Close()
		err := client.Handshake()
		if err != nil {
			panic(err)
		}
		if _, err = client.Write(nil); err != nil {
			panic(err)
		}
		if _, err = client.Write([]byte("hello")); err != nil {
			panic(err)
		}
		if _, err = client.Write([]byte("world")); err != nil {
			panic(err)
		}
		if _, err = client.Write(make([]byte, 20*1024)); err != nil {
			panic(err)
		}
		close(clientComplete)
	}()

	serverComplete := make(chan bool)
	go func() {
		defer y.Close()
		err := server.Handshake()
		if err != nil {
			panic(err)
		}

		h := sha256.New()
		if _, err := io.Copy(h, server); err != nil {
			panic(err)
		}
		if h.Sum(nil)[0] != 0xec {
			panic("bad data received")
		}
		close(serverComplete)
	}()

	<-clientComplete
	<-serverComplete
}

// FillKeyExchange sets elements of kx with key exchange information from the
// ratchet.
func (r *Ratchet) FillKeyExchange(kx *pond.KeyExchange) error {
	if r.kxPrivate0 == nil || r.kxPrivate1 == nil {
		return errors.New("ratchet: handshake already complete")
	}

	var public0, public1 [32]byte
	curve25519.ScalarBaseMult(&public0, r.kxPrivate0)
	curve25519.ScalarBaseMult(&public1, r.kxPrivate1)

	kx.Dh = public0[:]
	kx.Dh1 = public1[:]

	return nil
}

func TestBox(t *testing.T) {
	var privateKey1, privateKey2 [32]byte
	for i := range privateKey1[:] {
		privateKey1[i] = 1
	}
	for i := range privateKey2[:] {
		privateKey2[i] = 2
	}

	var publicKey1 [32]byte
	curve25519.ScalarBaseMult(&publicKey1, &privateKey1)
	var message [64]byte
	for i := range message[:] {
		message[i] = 3
	}

	var nonce [24]byte
	for i := range nonce[:] {
		nonce[i] = 4
	}

	box := Seal(nil, message[:], &nonce, &publicKey1, &privateKey2)

	// expected was generated using the C implementation of NaCl.
	expected, _ := hex.DecodeString("78ea30b19d2341ebbdba54180f821eec265cf86312549bea8a37652a8bb94f07b78a73ed1708085e6ddd0e943bbdeb8755079a37eb31d86163ce241164a47629c0539f330b4914cd135b3855bc2a2dfc")

	if !bytes.Equal(box, expected) {
		t.Fatalf("box didn't match, got\n%x\n, expected\n%x", box, expected)
	}
}

func UnmarshalKeyExchange(rand io.Reader, meetingPlace MeetingPlace, serialised []byte) (*KeyExchange, error) {
	var p panda_proto.KeyExchange
	if err := proto.Unmarshal(serialised, &p); err != nil {
		return nil, err
	}

	sharedSecret, ok := newSharedSecret(p.SharedSecret)
	if !ok {
		return nil, errors.New("panda: invalid shared secret in serialised key exchange")
	}

	kx := &KeyExchange{
		rand:         rand,
		meetingPlace: meetingPlace,
		status:       p.GetStatus(),
		sharedSecret: sharedSecret,
		serialised:   serialised,
		kxBytes:      p.KeyExchangeBytes,
		message1:     p.Message1,
		message2:     p.Message2,
	}

	copy(kx.key[:], p.Key)
	copy(kx.meeting1[:], p.Meeting1)
	copy(kx.meeting2[:], p.Meeting2)
	copy(kx.sharedKey[:], p.SharedKey)
	copy(kx.dhPrivate[:], p.DhPrivate)
	curve25519.ScalarBaseMult(&kx.dhPublic, &kx.dhPrivate)

	return kx, nil
}

func (c *client) dialServer(server string, useRandomIdentity bool) (*transport.Conn, error) {
	identity := &c.identity
	identityPublic := &c.identityPublic
	if useRandomIdentity {
		var randomIdentity [32]byte
		c.randBytes(randomIdentity[:])

		var randomIdentityPublic [32]byte
		curve25519.ScalarBaseMult(&randomIdentityPublic, &randomIdentity)

		identity = &randomIdentity
		identityPublic = &randomIdentityPublic
	}

	serverIdentity, host, err := parseServer(server, c.testing)
	if err != nil {
		return nil, err
	}
	var tor proxy.Dialer
	if c.testing {
		tor = proxy.Direct
	} else {
		tor = c.torDialer()
	}
	rawConn, err := tor.Dial("tcp", host)
	if err != nil {
		return nil, err
	}
	conn := transport.NewClient(rawConn, identity, identityPublic, serverIdentity)
	if err := conn.Handshake(); err != nil {
		return nil, err
	}
	return conn, nil
}

func NewTestServer(setup func(dir string)) *TestServer {
	listener, err := net.ListenTCP("tcp", &net.TCPAddr{IP: net.IPv4(127, 0, 0, 1)})
	if err != nil {
		panic(err)
	}

	dir, err := ioutil.TempDir("", "servertest")
	if err != nil {
		panic(err)
	}

	if setup != nil {
		setup(dir)
	}

	testServer := &TestServer{
		listener: listener,
		addr:     listener.Addr().(*net.TCPAddr),
		dir:      dir,
		server:   NewServer(dir, true),
	}
	io.ReadFull(rand.Reader, testServer.identity[:])
	curve25519.ScalarBaseMult(&testServer.identityPublic, &testServer.identity)

	go testServer.Loop()
	return testServer
}

// GenerateKey returns an appropriate private and public key pair
// for securing messages.
func GenerateKey() (priv *[PrivateKeySize]byte, pub *[PublicKeySize]byte, ok bool) {
	var priv1 [32]byte
	var priv2 [32]byte
	var pub1 [32]byte
	var pub2 [32]byte

	_, err := io.ReadFull(PRNG, priv1[:])
	if err != nil {
		return
	}

	_, err = io.ReadFull(PRNG, priv2[:])
	if err != nil {
		return
	}

	h := sha3.NewKeccak384()
	h.Write(priv1[:])
	digest := h.Sum(nil)
	copy(priv1[:], digest)
	priv1[0] &= 248
	priv1[31] &= 127
	priv1[31] |= 64

	h.Reset()
	h.Write(priv2[:])
	digest = h.Sum(nil)
	copy(priv2[:], digest)
	priv2[0] &= 248
	priv2[31] &= 127
	priv2[31] |= 64

	curve25519.ScalarBaseMult(&pub1, &priv1)
	curve25519.ScalarBaseMult(&pub2, &priv2)
	priv = new([PrivateKeySize]byte)
	copy(priv[:32], priv1[:])
	copy(priv[32:], priv2[:])

	pub = new([PublicKeySize]byte)
	copy(pub[:32], pub1[:])
	copy(pub[32:], pub2[:])
	secretbox.Zero(priv1[:])
	secretbox.Zero(priv2[:])

	ok = true
	return
}

// Pubkey returns the associated public key for the supplied private key.
func (k *Private) Pubkey() *Public {
	var pub [32]byte
	priv := [32]byte(*k)

	// Performs ScalarBaseMult on the supplied private key, returning the public key
	curve25519.ScalarBaseMult(&pub, &priv)
	public := Public(pub)
	return &public
}

func (c *client) doCreateAccount() error {
	_, _, err := parseServer(c.server, c.dev)
	if err != nil {
		return err
	}

	if !c.dev {
		// Check that Tor is running.
		testConn, err := net.Dial("tcp", c.torAddress)
		if err != nil {
			return errors.New("Failed to connect to local Tor: " + err.Error())
		}
		testConn.Close()
	}

	c.ui.Actions() <- SetText{name: "status", text: "Generating keys..."}
	c.ui.Signal()

	c.randBytes(c.identity[:])
	curve25519.ScalarBaseMult(&c.identityPublic, &c.identity)

	c.ui.Actions() <- SetText{name: "status", text: "Connecting..."}
	c.ui.Signal()

	conn, err := c.dialServer(c.server, false)
	if err != nil {
		return err
	}
	defer conn.Close()

	c.ui.Actions() <- SetText{name: "status", text: "Requesting new account..."}
	c.ui.Signal()

	c.generation = uint32(c.randId())

	request := new(pond.Request)
	request.NewAccount = &pond.NewAccount{
		Generation: proto.Uint32(c.generation),
		Group:      c.groupPriv.Group.Marshal(),
	}
	if err := conn.WriteProto(request); err != nil {
		return err
	}

	reply := new(pond.Reply)
	if err := conn.ReadProto(reply); err != nil {
		return err
	}
	if err := replyToError(reply); err != nil {
		return err
	}

	c.ui.Actions() <- SetText{name: "status", text: "Done"}
	c.ui.Signal()

	return nil
}

// GetKeyExchangeMaterial returns key exchange information from the
// ratchet.
func (r *Ratchet) GetKeyExchangeMaterial() (kx *KeyExchange, err error) {
	if r.kxPrivate0 == nil || r.kxPrivate1 == nil {
		return new(KeyExchange), errors.New("ratchet: handshake already complete")
	}

	var public0, public1, myIdentity [32]byte
	curve25519.ScalarBaseMult(&public0, r.kxPrivate0)
	curve25519.ScalarBaseMult(&public1, r.kxPrivate1)
	curve25519.ScalarBaseMult(&myIdentity, &r.myIdentityPrivate)

	kx = &KeyExchange{
		IdentityPublic: toSlice(myIdentity),
		Dh:             toSlice(public0),
		Dh1:            toSlice(public1),
	}

	return
}

func TestHandshake(t *testing.T) {
	var serverPrivate, clientPrivate, serverPublic, clientPublic [32]byte

	randBytes(serverPrivate[:])
	randBytes(clientPrivate[:])
	curve25519.ScalarBaseMult(&serverPublic, &serverPrivate)
	curve25519.ScalarBaseMult(&clientPublic, &clientPrivate)

	clientError, serverError := runHandshake(&clientPrivate, &clientPublic, &serverPrivate, &serverPublic)
	if clientError != nil || serverError != nil {
		t.Fatalf("handshake failed: client:'%s' server:'%s'", clientError, serverError)
	}

	serverPublic[0] ^= 0x40
	clientError, serverError = runHandshake(&clientPrivate, &clientPublic, &serverPrivate, &serverPublic)
	if clientError == nil && serverError == nil {
		t.Fatal("bad handshake succeeded")
	}
}

func pairedRatchet() (a, b *Ratchet) {
	var privA, pubA, privB, pubB [32]byte
	io.ReadFull(rand.Reader, privA[:])
	io.ReadFull(rand.Reader, privB[:])
	curve25519.ScalarBaseMult(&pubA, &privA)
	curve25519.ScalarBaseMult(&pubB, &privB)

	// These are the "Ed25519" public keys for the two parties. Of course,
	// they're not actually valid Ed25519 keys but that doesn't matter
	// here.
	var aSigningPublic, bSigningPublic [32]byte
	io.ReadFull(rand.Reader, aSigningPublic[:])
	io.ReadFull(rand.Reader, bSigningPublic[:])

	a, b = New(rand.Reader), New(rand.Reader)
	a.Now = nowFunc
	b.Now = nowFunc
	a.MyIdentityPrivate = &privA
	b.MyIdentityPrivate = &privB
	a.TheirIdentityPublic = &pubB
	b.TheirIdentityPublic = &pubA
	a.MySigningPublic = &aSigningPublic
	b.MySigningPublic = &bSigningPublic
	a.TheirSigningPublic = &bSigningPublic
	b.TheirSigningPublic = &aSigningPublic

	kxA, kxB := new(pond.KeyExchange), new(pond.KeyExchange)
	if err := a.FillKeyExchange(kxA); err != nil {
		panic(err)
	}
	if err := b.FillKeyExchange(kxB); err != nil {
		panic(err)
	}
	if err := a.CompleteKeyExchange(kxB, true); err != nil {
		panic(err)
	}
	if err := b.CompleteKeyExchange(kxA, true); err != nil {
		panic(err)
	}

	return
}

func (e *curve25519ECDH) GenerateKey(rand io.Reader) (crypto.PrivateKey, crypto.PublicKey, error) {
	var pub, priv [32]byte
	var err error

	_, err = io.ReadFull(rand, priv[:])
	if err != nil {
		return nil, nil, err
	}

	curve25519.ScalarBaseMult(&pub, &priv)
	return &priv, &pub, nil
}

// GenerateKey generates a new public/private key pair suitable for use with
// Seal and Open.
func GenerateKey(rand io.Reader) (publicKey, privateKey *[32]byte, err error) {
	publicKey = new([32]byte)
	privateKey = new([32]byte)
	_, err = io.ReadFull(rand, privateKey[:])
	if err != nil {
		publicKey = nil
		privateKey = nil
		return
	}

	curve25519.ScalarBaseMult(publicKey, privateKey)
	return
}

func (noise255) GenerateKey(random io.Reader) (Key, error) {
	var pubKey, privKey [32]byte
	if random == nil {
		random = rand.Reader
	}
	if _, err := io.ReadFull(random, privKey[:]); err != nil {
		return Key{}, err
	}
	privKey[0] &= 248
	privKey[31] &= 127
	privKey[31] |= 64
	curve25519.ScalarBaseMult(&pubKey, &privKey)
	return Key{Private: privKey[:], Public: pubKey[:]}, nil
}