lib/protocol: Remove support for v0.13 hello messages (#5461)

lib/protocol/bep_extensions.go

@@ -17,8 +17,9 @@ import (
 )
 
 const (
-	SyntheticDirectorySize = 128
-	HelloMessageMagic      = uint32(0x2EA7D90B)
+	SyntheticDirectorySize        = 128
+	HelloMessageMagic      uint32 = 0x2EA7D90B
+	Version13HelloMagic    uint32 = 0x9F79BC40 // old
 )
 
 func (m Hello) Magic() uint32 {

lib/protocol/hello.go

@@ -26,12 +26,9 @@ type HelloResult struct {
 }
 
 var (
-	// ErrTooOldVersion12 is returned by ExchangeHello when the other side
-	// speaks the older, incompatible version 0.12 of the protocol.
-	ErrTooOldVersion12 = errors.New("the remote device speaks an older version of the protocol (v0.12) not compatible with this version")
-	// ErrTooOldVersion13 is returned by ExchangeHello when the other side
-	// speaks the older, incompatible version 0.12 of the protocol.
-	ErrTooOldVersion13 = errors.New("the remote device speaks an older version of the protocol (v0.13) not compatible with this version")
+	// ErrTooOldVersion is returned by ExchangeHello when the other side
+	// speaks an older, incompatible version of the protocol.
+	ErrTooOldVersion = errors.New("the remote device speaks an older version of the protocol not compatible with this version")
 	// ErrUnknownMagic is returned by ExchangeHellow when the other side
 	// speaks something entirely unknown.
 	ErrUnknownMagic = errors.New("the remote device speaks an unknown (newer?) version of the protocol")
@@ -48,7 +45,7 @@ func ExchangeHello(c io.ReadWriter, h HelloIntf) (HelloResult, error) {
 // version mismatch that we might want to alert the user about.
 func IsVersionMismatch(err error) bool {
 	switch err {
-	case ErrTooOldVersion12, ErrTooOldVersion13, ErrUnknownMagic:
+	case ErrTooOldVersion, ErrUnknownMagic:
 		return true
 	default:
 		return false
@@ -87,31 +84,11 @@ func readHello(c io.Reader) (HelloResult, error) {
 		}
 		return res, nil
 
-	case Version13HelloMagic:
-		// This is a v0.13 Hello message in XDR format
-		if _, err := io.ReadFull(c, header[:4]); err != nil {
-			return HelloResult{}, err
-		}
-		msgSize := binary.BigEndian.Uint32(header[:4])
-		if msgSize > 1024 {
-			return HelloResult{}, fmt.Errorf("hello message too big")
-		}
-		buf := make([]byte, msgSize)
-		if _, err := io.ReadFull(c, buf); err != nil {
-			return HelloResult{}, err
-		}
-
-		var hello Version13HelloMessage
-		if err := hello.UnmarshalXDR(buf); err != nil {
-			return HelloResult{}, err
-		}
-		res := HelloResult(hello)
-		return res, ErrTooOldVersion13
-
-	case 0x00010001, 0x00010000:
-		// This is the first word of a v0.12 cluster config message.
-		// (Version 0, message ID 1, message type 0, compression enabled or disabled)
-		return HelloResult{}, ErrTooOldVersion12
+	case 0x00010001, 0x00010000, Version13HelloMagic:
+		// This is the first word of an older cluster config message or an
+		// old magic number. (Version 0, message ID 1, message type 0,
+		// compression enabled or disabled)
+		return HelloResult{}, ErrTooOldVersion
 	}
 
 	return HelloResult{}, ErrUnknownMagic

lib/protocol/hello_test.go

@@ -60,126 +60,39 @@ func TestVersion14Hello(t *testing.T) {
 	}
 }
 
-func TestVersion13Hello(t *testing.T) {
-	// Tests that we can send and receive a version 0.13 hello message.
+func TestOldHelloMsgs(t *testing.T) {
+	// Tests that we can correctly identify old/missing/unknown hello
+	// messages.
 
-	expected := Version13HelloMessage{
-		DeviceName:    "test device",
-		ClientName:    "syncthing",
-		ClientVersion: "v0.13.5",
+	cases := []struct {
+		msg string
+		err error
+	}{
+		{"00010001", ErrTooOldVersion}, // v12
+		{"9F79BC40", ErrTooOldVersion}, // v13
+		{"12345678", ErrUnknownMagic},
 	}
-	msgBuf := expected.MustMarshalXDR()
 
-	hdrBuf := make([]byte, 8)
-	binary.BigEndian.PutUint32(hdrBuf, Version13HelloMagic)
-	binary.BigEndian.PutUint32(hdrBuf[4:], uint32(len(msgBuf)))
+	for _, tc := range cases {
+		msg, _ := hex.DecodeString(tc.msg)
 
-	outBuf := new(bytes.Buffer)
-	outBuf.Write(hdrBuf)
-	outBuf.Write(msgBuf)
+		outBuf := new(bytes.Buffer)
+		outBuf.Write(msg)
 
-	inBuf := new(bytes.Buffer)
+		inBuf := new(bytes.Buffer)
 
-	conn := &readWriter{outBuf, inBuf}
-
-	send := Version13HelloMessage{
-		DeviceName:    "this device",
-		ClientName:    "other client",
-		ClientVersion: "v0.13.6",
-	}
-
-	res, err := ExchangeHello(conn, send)
-	if err != ErrTooOldVersion13 {
-		t.Errorf("unexpected error %v != ErrTooOldVersion13", err)
-	}
-
-	if res.ClientName != expected.ClientName {
-		t.Errorf("incorrect ClientName %q != expected %q", res.ClientName, expected.ClientName)
-	}
-	if res.ClientVersion != expected.ClientVersion {
-		t.Errorf("incorrect ClientVersion %q != expected %q", res.ClientVersion, expected.ClientVersion)
-	}
-	if res.DeviceName != expected.DeviceName {
-		t.Errorf("incorrect DeviceName %q != expected %q", res.DeviceName, expected.DeviceName)
-	}
-}
+		conn := &readWriter{outBuf, inBuf}
 
-func TestVersion12Hello(t *testing.T) {
-	// Tests that we can correctly interpret the lack of a hello message
-	// from a v0.12 client.
-
-	// This is the typical v0.12 connection start - our message header for a
-	// ClusterConfig message and then the cluster config message data. Taken
-	// from a protocol dump of a recent v0.12 client.
-	msg, _ := hex.DecodeString(spaceRe.ReplaceAllString(`
-	00010001
-	0000014a
-	7802000070000000027332000100a00973796e637468696e670e00b000000876
-	302e31322e32352400b00000000764656661756c741e00f01603000000204794
-	03ffdef496b5f5e5bc9c0a15221e70073164509fa30761af63094f6f945c3800
-	2073312f00f20b0001000000157463703a2f2f3132372e302e302e313a323230
-	301f00012400080500003000001000f1122064516fb94d24e7b637d20d9846eb
-	aeffb09556ef3968c8276fefc3fe24c144c2640002c0000034000f640002021f
-	00004f00090400003000001100f11220dff67945f05bdab4270acd6057f1eacf
-	a3ac93cade07ce6a89384c181ad6b80e640010332b000fc80007021f00012400
-	080500046400041400f21f2dc2af5c5f28e38384295f2fc2af2052c3a46b736d
-	c3b67267c3a57320e58aa8e4bd9c20d090d0b4d180d0b5d18136001f026c01b8
-	90000000000000000000`, ``))
-
-	outBuf := new(bytes.Buffer)
-	outBuf.Write(msg)
-
-	inBuf := new(bytes.Buffer)
-
-	conn := &readWriter{outBuf, inBuf}
-
-	send := Version13HelloMessage{
-		DeviceName:    "this device",
-		ClientName:    "other client",
-		ClientVersion: "v0.13.6",
-	}
-
-	_, err := ExchangeHello(conn, send)
-	if err != ErrTooOldVersion12 {
-		t.Errorf("unexpected error %v != ErrTooOldVersion12", err)
-	}
-}
-
-func TestUnknownHello(t *testing.T) {
-	// Tests that we react correctly to a completely unknown magic number.
-
-	// This is an unknown magic follow byte some message data.
-	msg, _ := hex.DecodeString(spaceRe.ReplaceAllString(`
-	12345678
-	0000014a
-	7802000070000000027332000100a00973796e637468696e670e00b000000876
-	302e31322e32352400b00000000764656661756c741e00f01603000000204794
-	03ffdef496b5f5e5bc9c0a15221e70073164509fa30761af63094f6f945c3800
-	2073312f00f20b0001000000157463703a2f2f3132372e302e302e313a323230
-	301f00012400080500003000001000f1122064516fb94d24e7b637d20d9846eb
-	aeffb09556ef3968c8276fefc3fe24c144c2640002c0000034000f640002021f
-	00004f00090400003000001100f11220dff67945f05bdab4270acd6057f1eacf
-	a3ac93cade07ce6a89384c181ad6b80e640010332b000fc80007021f00012400
-	080500046400041400f21f2dc2af5c5f28e38384295f2fc2af2052c3a46b736d
-	c3b67267c3a57320e58aa8e4bd9c20d090d0b4d180d0b5d18136001f026c01b8
-	90000000000000000000`, ``))
-
-	outBuf := new(bytes.Buffer)
-	outBuf.Write(msg)
-
-	inBuf := new(bytes.Buffer)
-
-	conn := &readWriter{outBuf, inBuf}
-
-	send := Version13HelloMessage{
-		DeviceName:    "this device",
-		ClientName:    "other client",
-		ClientVersion: "v0.13.6",
-	}
+		send := &Hello{
+			DeviceName:    "this device",
+			ClientName:    "other client",
+			ClientVersion: "v1.0.0",
+		}
 
-	_, err := ExchangeHello(conn, send)
-	if err != ErrUnknownMagic {
-		t.Errorf("unexpected error %v != ErrUnknownMagic", err)
+		_, err := ExchangeHello(conn, send)
+		if err != tc.err {
+			t.Errorf("unexpected error %v != %v", err, tc.err)
+		}
 	}
 }
 

lib/protocol/hello_v0.13.go

@@ -1,24 +0,0 @@
-// Copyright (C) 2016 The Protocol Authors.
-
-//go:generate -command genxdr go run ../../repos/xdr/cmd/genxdr/main.go
-//go:generate genxdr -o hello_v0.13_xdr.go hello_v0.13.go
-
-package protocol
-
-var (
-	Version13HelloMagic uint32 = 0x9F79BC40
-)
-
-type Version13HelloMessage struct {
-	DeviceName    string // max:64
-	ClientName    string // max:64
-	ClientVersion string // max:64
-}
-
-func (m Version13HelloMessage) Magic() uint32 {
-	return Version13HelloMagic
-}
-
-func (m Version13HelloMessage) Marshal() ([]byte, error) {
-	return m.MarshalXDR()
-}

lib/protocol/hello_v0.13_xdr.go

@@ -1,85 +0,0 @@
-// ************************************************************
-// This file is automatically generated by genxdr. Do not edit.
-// ************************************************************
-
-package protocol
-
-import (
-	"github.com/calmh/xdr"
-)
-
-/*
-
-Version13HelloMessage Structure:
-
- 0                   1                   2                   3
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-/                                                               /
-\              Device Name (length + padded data)               \
-/                                                               /
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-/                                                               /
-\              Client Name (length + padded data)               \
-/                                                               /
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-/                                                               /
-\             Client Version (length + padded data)             \
-/                                                               /
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
-
-struct Version13HelloMessage {
-	string DeviceName<64>;
-	string ClientName<64>;
-	string ClientVersion<64>;
-}
-
-*/
-
-func (o Version13HelloMessage) XDRSize() int {
-	return 4 + len(o.DeviceName) + xdr.Padding(len(o.DeviceName)) +
-		4 + len(o.ClientName) + xdr.Padding(len(o.ClientName)) +
-		4 + len(o.ClientVersion) + xdr.Padding(len(o.ClientVersion))
-}
-
-func (o Version13HelloMessage) MarshalXDR() ([]byte, error) {
-	buf := make([]byte, o.XDRSize())
-	m := &xdr.Marshaller{Data: buf}
-	return buf, o.MarshalXDRInto(m)
-}
-
-func (o Version13HelloMessage) MustMarshalXDR() []byte {
-	bs, err := o.MarshalXDR()
-	if err != nil {
-		panic(err)
-	}
-	return bs
-}
-
-func (o Version13HelloMessage) MarshalXDRInto(m *xdr.Marshaller) error {
-	if l := len(o.DeviceName); l > 64 {
-		return xdr.ElementSizeExceeded("DeviceName", l, 64)
-	}
-	m.MarshalString(o.DeviceName)
-	if l := len(o.ClientName); l > 64 {
-		return xdr.ElementSizeExceeded("ClientName", l, 64)
-	}
-	m.MarshalString(o.ClientName)
-	if l := len(o.ClientVersion); l > 64 {
-		return xdr.ElementSizeExceeded("ClientVersion", l, 64)
-	}
-	m.MarshalString(o.ClientVersion)
-	return m.Error
-}
-
-func (o *Version13HelloMessage) UnmarshalXDR(bs []byte) error {
-	u := &xdr.Unmarshaller{Data: bs}
-	return o.UnmarshalXDRFrom(u)
-}
-func (o *Version13HelloMessage) UnmarshalXDRFrom(u *xdr.Unmarshaller) error {
-	o.DeviceName = u.UnmarshalStringMax(64)
-	o.ClientName = u.UnmarshalStringMax(64)
-	o.ClientVersion = u.UnmarshalStringMax(64)
-	return u.Error
-}