basic capability negotiation

- multi-prefix is supported as an example

irc/channel.go

@@ -54,18 +54,26 @@ func (channel *Channel) ClientIsOperator(client *Client) bool {
 	return client.flags[Operator] || channel.members.HasMode(client, ChannelOperator)
 }
 
-func (channel *Channel) Nicks() []string {
+func (channel *Channel) Nicks(target *Client) []string {
+	isMultiPrefix := (target != nil) && target.capabilities[MultiPrefix]
 	nicks := make([]string, len(channel.members))
 	i := 0
 	for client, modes := range channel.members {
-		switch {
+		if isMultiPrefix {
-		case modes[ChannelOperator]:
+			if modes[ChannelOperator] {
-			nicks[i] = "@" + client.Nick()
+				nicks[i] += "@"
-		case modes[Voice]:
-			nicks[i] = "+" + client.Nick()
-		default:
-			nicks[i] = client.Nick()
 			}
+			if modes[Voice] {
+				nicks[i] += "+"
+			}
+		} else {
+			if modes[ChannelOperator] {
+				nicks[i] += "@"
+			} else if modes[Voice] {
+				nicks[i] += "+"
+			}
+		}
+		nicks[i] += client.Nick()
 		i += 1
 	}
 	return nicks

irc/client.go

@@ -13,7 +13,10 @@ func IsNickname(nick string) bool {
 
 type Client struct {
 	atime        time.Time
+	authorized   bool
 	awayMessage  string
+	capabilities CapabilitySet
+	capState     CapState
 	channels     ChannelSet
 	commands     chan editableCommand
 	ctime        time.Time
@@ -36,11 +39,13 @@ func NewClient(server *Server, conn net.Conn) *Client {
 	now := time.Now()
 	client := &Client{
 		atime:        now,
+		capState:     CapNone,
+		capabilities: make(CapabilitySet),
 		channels:     make(ChannelSet),
 		commands:     make(chan editableCommand),
 		ctime:        now,
 		flags:        make(map[UserMode]bool),
-		phase:    server.InitPhase(),
+		phase:        Registration,
 		server:       server,
 	}
 	client.socket = NewSocket(conn, client.commands)
@@ -68,6 +73,12 @@ func (client *Client) run() {
 	}
 }
 
+func (client *Client) connectionTimeout() {
+	client.commands <- &QuitCommand{
+		message: "connection timeout",
+	}
+}
+
 //
 // idle timer goroutine
 //
@@ -76,14 +87,6 @@ func (client *Client) connectionIdle() {
 	client.server.idle <- client
 }
 
-//
-// quit timer goroutine
-//
-
-func (client *Client) connectionTimeout() {
-	client.server.timeout <- client
-}
-
 //
 // server goroutine
 //

irc/commands.go

@@ -706,20 +706,35 @@ func NewOperCommand(args []string) (editableCommand, error) {
 	return cmd, nil
 }
 
-// TODO
 type CapCommand struct {
 	BaseCommand
+	subCommand CapSubCommand
 	args       []string
 }
 
 func (msg *CapCommand) String() string {
-	return fmt.Sprintf("CAP(args=%s)", msg.args)
+	return fmt.Sprintf("CAP(subCommand=%s, args=%s)", msg.subCommand, msg.args)
+}
+
+func (msg *CapCommand) Capabilities() []Capability {
+	strs := strings.Split(msg.args[0], " ")
+	caps := make([]Capability, len(strs))
+	for index, str := range strs {
+		caps[index] = Capability(str)
+	}
+	return caps
 }
 
 func NewCapCommand(args []string) (editableCommand, error) {
-	return &CapCommand{
+	if len(args) < 1 {
-		args: args,
+		return nil, NotEnoughArgsError
-	}, nil
+	}
+
+	cmd := &CapCommand{
+		subCommand: CapSubCommand(args[0]),
+		args:       args[1:],
+	}
+	return cmd, nil
 }
 
 // HAPROXY support

irc/constants.go

@@ -155,6 +155,7 @@ const (
 	ERR_TOOMANYTARGETS    NumericCode = 407
 	ERR_NOSUCHSERVICE     NumericCode = 408
 	ERR_NOORIGIN          NumericCode = 409
+	ERR_INVALIDCAPCMD     NumericCode = 410
 	ERR_NORECIPIENT       NumericCode = 411
 	ERR_NOTEXTTOSEND      NumericCode = 412
 	ERR_NOTOPLEVEL        NumericCode = 413
@@ -200,6 +201,14 @@ const (
 	ERR_UMODEUNKNOWNFLAG  NumericCode = 501
 	ERR_USERSDONTMATCH    NumericCode = 502
 
+	CAP_LS    CapSubCommand = "LS"
+	CAP_LIST  CapSubCommand = "LIST"
+	CAP_REQ   CapSubCommand = "REQ"
+	CAP_ACK   CapSubCommand = "ACK"
+	CAP_NAK   CapSubCommand = "NAK"
+	CAP_CLEAR CapSubCommand = "CLEAR"
+	CAP_END   CapSubCommand = "END"
+
 	Add    ModeOp = '+'
 	List   ModeOp = '='
 	Remove ModeOp = '-'
@@ -230,10 +239,28 @@ const (
 	Secret          ChannelMode = 's' // flag, deprecated
 	UserLimit       ChannelMode = 'l' // flag arg
 	Voice           ChannelMode = 'v' // arg
+
+	MultiPrefix Capability = "multi-prefix"
+	SASL        Capability = "sasl"
+
+	Disable CapModifier = '-'
+	Ack     CapModifier = '~'
+	Sticky  CapModifier = '='
+)
+
+var (
+	SupportedCapabilities = CapabilitySet{
+		MultiPrefix: true,
+	}
 )
 
 const (
-	Authorization Phase = iota
 	Registration Phase = iota
 	Normal       Phase = iota
 )
+
+const (
+	CapNone        CapState = iota
+	CapNegotiating CapState = iota
+	CapNegotiated  CapState = iota
+)

irc/reply.go

@@ -240,13 +240,21 @@ func (target *Client) RplWhoReply(channel *Channel, client *Client) {
 
 	if channel != nil {
 		channelName = channel.name
-
+		if target.capabilities[MultiPrefix] {
+			if channel.members[client][ChannelOperator] {
+				flags += "@"
+			}
+			if channel.members[client][Voice] {
+				flags += "+"
+			}
+		} else {
 			if channel.members[client][ChannelOperator] {
 				flags += "@"
 			} else if channel.members[client][Voice] {
 				flags += "+"
 			}
 		}
+	}
 	target.NumericReply(RPL_WHOREPLY,
 		"%s %s %s %s %s %s :%d %s", channelName, client.username, client.hostname,
 		client.server.name, client.Nick(), flags, client.hops, client.realname)
@@ -360,7 +368,7 @@ func (target *Client) RplListEnd(server *Server) {
 }
 
 func (target *Client) RplNamReply(channel *Channel) {
-	target.MultilineReply(channel.Nicks(), RPL_NAMREPLY,
+	target.MultilineReply(channel.Nicks(target), RPL_NAMREPLY,
 		"= %s :%s", channel)
 }
 
@@ -502,3 +510,8 @@ func (target *Client) ErrChannelIsFull(channel *Channel) {
 	target.NumericReply(ERR_CHANNELISFULL,
 		"%s :Cannot join channel (+l)", channel)
 }
+
+func (target *Client) ErrInvalidCapCmd(subCommand CapSubCommand) {
+	target.NumericReply(ERR_INVALIDCAPCMD,
+		"%s :Invalid CAP subcommand", subCommand)
+}

irc/server.go

@@ -32,7 +32,6 @@ type Server struct {
 	operators map[string][]byte
 	password  []byte
 	signals   chan os.Signal
-	timeout   chan *Client
 }
 
 func NewServer(config *Config) *Server {
@@ -54,7 +53,6 @@ func NewServer(config *Config) *Server {
 		operators: config.OperatorsMap(),
 		password:  config.PasswordBytes(),
 		signals:   make(chan os.Signal, 1),
-		timeout:   make(chan *Client, 16),
 	}
 
 	signal.Notify(server.signals, os.Interrupt, os.Kill)
@@ -101,14 +99,6 @@ func (server *Server) processCommand(cmd Command) {
 	}
 
 	switch client.phase {
-	case Authorization:
-		authCmd, ok := cmd.(AuthServerCommand)
-		if !ok {
-			client.Quit("unexpected command")
-			return
-		}
-		authCmd.HandleAuthServer(server)
-
 	case Registration:
 		regCmd, ok := cmd.(RegServerCommand)
 		if !ok {
@@ -117,7 +107,7 @@ func (server *Server) processCommand(cmd Command) {
 		}
 		regCmd.HandleRegServer(server)
 
-	default:
+	case Normal:
 		srvCmd, ok := cmd.(ServerCommand)
 		if !ok {
 			client.ErrUnknownCommand(cmd.Code())
@@ -155,20 +145,10 @@ func (server *Server) Run() {
 
 		case client := <-server.idle:
 			client.Idle()
-
-		case client := <-server.timeout:
-			client.Quit("connection timeout")
 		}
 	}
 }
 
-func (server *Server) InitPhase() Phase {
-	if server.password == nil {
-		return Registration
-	}
-	return Authorization
-}
-
 func newListener(config ListenerConfig) (net.Listener, error) {
 	if config.IsTLS() {
 		certificate, err := tls.LoadX509KeyPair(config.Certificate, config.Key)
@@ -237,7 +217,7 @@ func (s *Server) GenerateGuestNick() string {
 //
 
 func (s *Server) tryRegister(c *Client) {
-	if c.HasNick() && c.HasUsername() {
+	if c.HasNick() && c.HasUsername() && (c.capState != CapNegotiating) {
 		c.Register()
 		c.RplWelcome()
 		c.RplYourHost()
@@ -297,18 +277,10 @@ func (s *Server) Nick() string {
 }
 
 //
-// authorization commands
+// registration commands
 //
 
-func (msg *ProxyCommand) HandleAuthServer(server *Server) {
+func (msg *PassCommand) HandleRegServer(server *Server) {
-	msg.Client().hostname = msg.hostname
-}
-
-func (msg *CapCommand) HandleAuthServer(server *Server) {
-	// TODO
-}
-
-func (msg *PassCommand) HandleAuthServer(server *Server) {
 	client := msg.Client()
 	if msg.err != nil {
 		client.ErrPasswdMismatch()
@@ -316,27 +288,62 @@ func (msg *PassCommand) HandleAuthServer(server *Server) {
 		return
 	}
 
-	client.phase = Registration
+	client.authorized = true
 }
 
-func (msg *QuitCommand) HandleAuthServer(server *Server) {
-	msg.Client().Quit(msg.message)
-}
-
-//
-// registration commands
-//
-
 func (msg *ProxyCommand) HandleRegServer(server *Server) {
 	msg.Client().hostname = msg.hostname
 }
 
 func (msg *CapCommand) HandleRegServer(server *Server) {
-	// TODO
+	client := msg.Client()
+
+	switch msg.subCommand {
+	case CAP_LS:
+		client.capState = CapNegotiating
+		client.Reply(fmt.Sprintf("CAP LS :%d", MultiPrefix))
+
+	case CAP_LIST:
+		client.Reply(fmt.Sprintf("CAP LIST :%s", client.capabilities))
+
+	case CAP_REQ:
+		client.capState = CapNegotiating
+		caps := msg.Capabilities()
+		if (len(caps) != 1) && (caps[0] != MultiPrefix) {
+			client.Reply("CAP NAK :" + msg.args[0])
+			return
+		}
+		for _, capability := range caps {
+			client.capabilities[capability] = true
+		}
+		client.Reply("CAP ACK :" + msg.args[0])
+
+	case CAP_CLEAR:
+		for capability := range client.capabilities {
+			delete(client.capabilities, capability)
+		}
+		client.Reply("CAP ACK :")
+
+	case CAP_END:
+		client.capState = CapNegotiated
+		server.tryRegister(client)
+
+	default:
+		client.ErrInvalidCapCmd(msg.subCommand)
+	}
 }
 
 func (m *NickCommand) HandleRegServer(s *Server) {
 	client := m.Client()
+	if !client.authorized {
+		client.ErrPasswdMismatch()
+		client.Quit("bad password")
+		return
+	}
+
+	if client.capState == CapNegotiating {
+		client.capState = CapNegotiated
+	}
 
 	if m.nickname == "" {
 		client.ErrNoNicknameGiven()
@@ -358,11 +365,22 @@ func (m *NickCommand) HandleRegServer(s *Server) {
 }
 
 func (msg *RFC1459UserCommand) HandleRegServer(server *Server) {
+	client := msg.Client()
+	if !client.authorized {
+		client.ErrPasswdMismatch()
+		client.Quit("bad password")
+		return
+	}
 	msg.HandleRegServer2(server)
 }
 
 func (msg *RFC2812UserCommand) HandleRegServer(server *Server) {
 	client := msg.Client()
+	if !client.authorized {
+		client.ErrPasswdMismatch()
+		client.Quit("bad password")
+		return
+	}
 	flags := msg.Flags()
 	if len(flags) > 0 {
 		for _, mode := range msg.Flags() {
@@ -375,6 +393,9 @@ func (msg *RFC2812UserCommand) HandleRegServer(server *Server) {
 
 func (msg *UserCommand) HandleRegServer2(server *Server) {
 	client := msg.Client()
+	if client.capState == CapNegotiating {
+		client.capState = CapNegotiated
+	}
 	client.username, client.realname = msg.username, msg.realname
 	server.tryRegister(client)
 }

irc/types.go

@@ -10,6 +10,25 @@ import (
 // simple types
 //
 
+type CapSubCommand string
+
+type Capability string
+
+type CapModifier rune
+
+type CapState uint
+
+type CapabilitySet map[Capability]bool
+
+func (set CapabilitySet) String() string {
+	strs := make([]string, len(set))
+	index := 0
+	for capability := range set {
+		strs[index] = string(capability)
+	}
+	return strings.Join(strs, " ")
+}
+
 // a string with wildcards
 type Mask string
 
@@ -24,7 +43,7 @@ func (op ModeOp) String() string {
 type UserMode rune
 
 func (mode UserMode) String() string {
-	return fmt.Sprintf("%c", mode)
+	return string(mode)
 }
 
 type Phase uint
@@ -49,7 +68,7 @@ func (code NumericCode) String() string {
 type ChannelMode rune
 
 func (mode ChannelMode) String() string {
-	return fmt.Sprintf("%c", mode)
+	return string(mode)
 }
 
 type ChannelNameMap map[string]*Channel