func (this *Session) HandlePacket(packet packet.Packet) (err error) {
switch this.state {
case STATE_DISCONNECTED:
if packet.Id() == minecraft.PACKET_SERVER_HANDSHAKE {
handshakePacket := packet.(*minecraft.PacketServerHandshake)
this.protocolVersion = handshakePacket.ProtocolVersion
this.serverAddress = handshakePacket.ServerAddress
supportedVersion := false
for _, version := range minecraft.Versions {
if version != this.protocolVersion {
continue
}
supportedVersion = true
break
}
if handshakePacket.State == 1 {
if !supportedVersion {
this.protocolVersion = minecraft.Versions[0]
}
this.pipeline.Replace("registry", minecraft.StatusPacketServerCodec)
this.state = STATE_STATUS
} else if handshakePacket.State == 2 {
if !supportedVersion {
err = errors.New("Protocol version does not match")
return
}
this.protocol17 = this.protocolVersion < minecraft.Versions[0]
if this.protocol17 {
this.pipeline.Replace("registry", minecraft.LoginPacketServerCodec17)
} else {
this.pipeline.Replace("registry", minecraft.LoginPacketServerCodec)
}
this.state = STATE_LOGIN
} else {
err = errors.New("Unexpected state")
return
}
} else {
err = errors.New("Unexpected packet")
return
}
case STATE_STATUS:
if packet.Id() == minecraft.PACKET_SERVER_STATUS_REQUEST {
samplePath := this.server.router.RouteSample(this.serverAddress)
sampleTxt, sampleErr := ioutil.ReadFile(samplePath)
sample := make([]map[string]interface{}, 0)
if sampleErr == nil {
lines := strings.Split(string(sampleTxt), "\n")
for _, line := range lines {
line = strings.Replace(line, "\r", "", -1)
if len(strings.TrimSpace(line)) == 0 {
continue
}
entry := make(map[string]interface{})
entry["name"] = minecraft.Colorize(line)
entry["id"] = "00000000-0000-0000-0000-000000000000"
sample = append(sample, entry)
}
}
icons := this.server.router.RouteIcons(this.serverAddress)
iconPath := icons[RandomInt(len(icons))]
icon, iconErr := ioutil.ReadFile(iconPath)
var iconString string
if iconErr == nil {
iconString = "data:image/png;base64," + base64.StdEncoding.EncodeToString(icon)
}
version := make(map[string]interface{})
version["name"] = minecraft.STRING_VERSION
version["protocol"] = this.protocolVersion
players := make(map[string]interface{})
if this.server.SyncMaxPlayers() {
players["max"] = this.server.connect.MaxPlayers()
} else {
players["max"] = this.server.MaxPlayers()
}
players["online"] = this.server.connect.Players()
players["sample"] = sample
description := make(map[string]interface{})
motds := this.server.router.RouteMotds(this.serverAddress)
motd := motds[RandomInt(len(motds))]
description["text"] = minecraft.Colorize(motd)
response := make(map[string]interface{})
response["version"] = version
response["players"] = players
response["description"] = description
if iconString != "" {
response["favicon"] = iconString
}
var marshalled []byte
marshalled, err = json.Marshal(response)
if err != nil {
return
}
err = this.Write(minecraft.NewPacketClientStatusResponse(string(marshalled)))
if err != nil {
return
}
this.state = STATE_STATUS_PING
} else {
err = errors.New("Unexpected packet")
return
}
case STATE_STATUS_PING:
if packet.Id() == minecraft.PACKET_SERVER_STATUS_PING {
err = this.Write(minecraft.NewPacketClientStatusPing(packet.(*minecraft.PacketServerStatusPing).Time))
if err != nil {
return
}
this.conn.Close()
} else {
err = errors.New("Unexpected packet")
return
}
case STATE_LOGIN:
if packet.Id() == minecraft.PACKET_SERVER_LOGIN_START {
this.name = packet.(*minecraft.PacketServerLoginStart).Name
if this.server.Authenticate() {
this.serverId, err = GenSalt()
if err != nil {
return
}
this.publicKey, err = x509.MarshalPKIXPublicKey(&this.server.privateKey.PublicKey)
if err != nil {
return
}
this.verifyToken, err = RandomBytes(4)
if err != nil {
return
}
err = this.Write(minecraft.NewPacketClientLoginEncryptRequest(this.serverId, this.publicKey, this.verifyToken))
if err != nil {
return
}
this.state = STATE_LOGIN_ENCRYPT
} else {
this.profile = auth.GameProfile{
Id: GenNameUUID("OfflinePlayer:" + this.name),
Properties: make([]auth.GameProfileProperty, 0),
}
this.SetAuthenticated(true)
}
} else {
err = errors.New("Unexpected packet")
return
}
case STATE_LOGIN_ENCRYPT:
if packet.Id() == minecraft.PACKET_SERVER_LOGIN_ENCRYPT_RESPONSE {
loginEncryptResponsePacket := packet.(*minecraft.PacketServerLoginEncryptResponse)
var sharedSecret []byte
sharedSecret, err = rsa.DecryptPKCS1v15(rand.Reader, this.server.privateKey, loginEncryptResponsePacket.SharedSecret)
if err != nil {
return
}
var verifyToken []byte
verifyToken, err = rsa.DecryptPKCS1v15(rand.Reader, this.server.privateKey, loginEncryptResponsePacket.VerifyToken)
if err != nil {
return
}
if bytes.Compare(this.verifyToken, verifyToken) != 0 {
err = errors.New("Verify token does not match")
return
}
err = this.SetEncryption(sharedSecret)
if err != nil {
return
}
var authErr error
this.profile, authErr = auth.Authenticate(this.name, this.serverId, sharedSecret, this.publicKey)
if authErr != nil {
this.SetAuthenticated(false)
fmt.Println("Proxy server, failed to authorize:", this.name, "ip:", this.remoteIp, "err:", authErr)
} else {
this.SetAuthenticated(true)
fmt.Println("Proxy server, authorized:", this.name, "ip:", this.remoteIp)
}
} else {
err = errors.New("Unexpected packet")
return
}
case STATE_CONNECTED:
if packet.Id() == minecraft.PACKET_SERVER_CLIENT_SETTINGS {
this.clientSettings = packet
}
if packet.Id() == minecraft.PACKET_SERVER_PLUGIN_MESSAGE {
pluginMessagePacket := packet.(*minecraft.PacketServerPluginMessage)
if pluginMessagePacket.Channel == "REGISTER" {
for _, channelBytes := range bytes.Split(pluginMessagePacket.Data[:], []byte{0}) {
channel := string(channelBytes)
if _, ok := this.pluginChannels[channel]; ok {
continue
}
if len(this.pluginChannels) >= 128 {
break
}
this.pluginChannels[channel] = struct{}{}
}
} else if pluginMessagePacket.Channel == "UNREGISTER" {
for _, channelBytes := range bytes.Split(pluginMessagePacket.Data[:], []byte{0}) {
channel := string(channelBytes)
delete(this.pluginChannels, channel)
}
}
}
if this.redirecting {
break
}
if genericPacket, ok := packet.(*minecraft.PacketGeneric); ok {
genericPacket.SwapEntities(this.clientEntityId, this.serverEntityId, false, this.protocol17)
}
this.outBridge.Write(packet)
}
return
}
func (this *Session) HandlePacket(packet packet.Packet) (err error) {
switch this.state {
case STATE_DISCONNECTED:
if packet.Id() == minecraft.PACKET_SERVER_HANDSHAKE {
handshakePacket := packet.(*minecraft.PacketServerHandshake)
this.serverAddress = handshakePacket.ServerAddress
if handshakePacket.State == 1 {
this.codec.SetEncodeCodec(minecraft.StatusPacketClientCodec)
this.codec.SetDecodeCodec(minecraft.StatusPacketServerCodec)
this.state = STATE_STATUS
} else if handshakePacket.State == 2 {
if handshakePacket.ProtocolVersion != minecraft.VERSION {
err = errors.New("Protocol version does not match")
return
}
this.codec.SetEncodeCodec(minecraft.LoginPacketClientCodec)
this.codec.SetDecodeCodec(minecraft.LoginPacketServerCodec)
this.state = STATE_LOGIN
} else {
err = errors.New("Unexpected state")
return
}
} else {
err = errors.New("Unexpected packet")
return
}
case STATE_STATUS:
if packet.Id() == minecraft.PACKET_SERVER_STATUS_REQUEST {
favicon, faviconErr := ioutil.ReadFile("server-icon.png")
var faviconString string
if faviconErr == nil {
faviconString = "data:image/png;base64," + base64.StdEncoding.EncodeToString(favicon)
}
version := make(map[string]interface{})
version["name"] = minecraft.STRING_VERSION
version["protocol"] = minecraft.VERSION
players := make(map[string]interface{})
players["max"] = this.server.Connect().MaxPlayers()
players["online"] = this.server.Connect().Players()
description := make(map[string]interface{})
description["text"] = minecraft.Colorize(this.server.Router().RouteMotd(this.serverAddress))
response := make(map[string]interface{})
response["version"] = version
response["players"] = players
response["description"] = description
if faviconString != "" {
response["favicon"] = faviconString
}
var marshalled []byte
marshalled, err = json.Marshal(response)
if err != nil {
return
}
err = this.Write(&minecraft.PacketClientStatusResponse{string(marshalled)})
if err != nil {
return
}
this.state = STATE_STATUS_PING
} else {
err = errors.New("Unexpected packet")
return
}
case STATE_STATUS_PING:
if packet.Id() == minecraft.PACKET_SERVER_STATUS_PING {
err = this.Write(&minecraft.PacketClientStatusPing{packet.(*minecraft.PacketServerStatusPing).Time})
if err != nil {
return
}
this.conn.Close()
} else {
err = errors.New("Unexpected packet")
return
}
case STATE_LOGIN:
if packet.Id() == minecraft.PACKET_SERVER_LOGIN_START {
this.name = packet.(*minecraft.PacketServerLoginStart).Name
if this.server.Authenticate() {
this.serverId, err = GenSalt()
if err != nil {
return
}
this.publicKey, err = x509.MarshalPKIXPublicKey(&this.server.PrivateKey().PublicKey)
if err != nil {
return
}
this.verifyToken, err = RandomBytes(4)
if err != nil {
return
}
err = this.Write(&minecraft.PacketClientLoginEncryptRequest{this.serverId, this.publicKey, this.verifyToken})
if err != nil {
return
}
this.state = STATE_LOGIN_ENCRYPT
} else {
this.uuid = GenNameUUID("OfflinePlayer:" + this.name)
this.SetAuthenticated(true)
}
} else {
err = errors.New("Unexpected packet")
return
}
case STATE_LOGIN_ENCRYPT:
if packet.Id() == minecraft.PACKET_SERVER_LOGIN_ENCRYPT_RESPONSE {
loginEncryptResponsePacket := packet.(*minecraft.PacketServerLoginEncryptResponse)
var sharedSecret []byte
sharedSecret, err = rsa.DecryptPKCS1v15(rand.Reader, this.server.PrivateKey(), loginEncryptResponsePacket.SharedSecret)
if err != nil {
return
}
var verifyToken []byte
verifyToken, err = rsa.DecryptPKCS1v15(rand.Reader, this.server.PrivateKey(), loginEncryptResponsePacket.VerifyToken)
if err != nil {
return
}
if bytes.Compare(this.verifyToken, verifyToken) != 0 {
err = errors.New("Verify token does not match")
return
}
var block cipher.Block
block, err = aes.NewCipher(sharedSecret)
if err != nil {
return
}
this.connCodec.SetReader(&cipher.StreamReader{
R: this.connCodec.Reader(),
S: minecraft.NewCFB8Decrypter(block, sharedSecret),
})
this.connCodec.SetWriter(&cipher.StreamWriter{
W: this.connCodec.Writer(),
S: minecraft.NewCFB8Encrypter(block, sharedSecret),
})
var authErr error
this.uuid, authErr = auth.Authenticate(this.name, this.serverId, sharedSecret, this.publicKey)
if authErr != nil {
this.SetAuthenticated(false)
fmt.Println("Proxy server, failed to authorize:", this.name, "ip:", this.RemoteIp(), "err:", authErr)
} else {
this.SetAuthenticated(true)
fmt.Println("Proxy server, authorized:", this.name, "ip:", this.RemoteIp())
}
} else {
err = errors.New("Unexpected packet")
return
}
case STATE_CONNECTED:
if packet.Id() == minecraft.PACKET_SERVER_CLIENT_SETTINGS {
this.clientSettings = packet
}
if this.redirecting {
break
}
if genericPacket, ok := packet.(*minecraft.PacketGeneric); ok {
genericPacket.SwapEntities(this.clientEntityId, this.serverEntityId, false)
}
this.outBridge.Write(packet)
}
return
}
