Allow clients to specify an upstream name in their username

downstream.go

@@ -58,6 +58,7 @@ type downstreamConn struct {
 	nick       string
 	username   string
 	realname   string
+	upstream   *Upstream
 }
 
 func newDownstreamConn(srv *Server, netConn net.Conn) *downstreamConn {
@@ -97,13 +98,38 @@ func (dc *downstreamConn) marshalChannel(uc *upstreamConn, name string) string {
 	return name
 }
 
-func (dc *downstreamConn) unmarshalChannel(name string) (*upstreamConn, string, error) {
+func (dc *downstreamConn) forEachUpstream(f func(*upstreamConn)) {
-	// TODO: extract network name from channel name
+	dc.user.forEachUpstream(func(uc *upstreamConn) {
-	ch, err := dc.user.getChannel(name)
+		if dc.upstream != nil && uc.upstream != dc.upstream {
-	if err != nil {
+			return
-		return nil, "", err
 		}
-	return ch.conn, ch.Name, nil
+		f(uc)
+	})
+}
+
+func (dc *downstreamConn) unmarshalChannel(name string) (*upstreamConn, string, error) {
+	// TODO: extract network name from channel name if dc.upstream == nil
+	var channel *upstreamChannel
+	var err error
+	dc.forEachUpstream(func(uc *upstreamConn) {
+		if err != nil {
+			return
+		}
+		if ch, ok := uc.channels[name]; ok {
+			if channel != nil {
+				err = fmt.Errorf("ambiguous channel name %q", name)
+			} else {
+				channel = ch
+			}
+		}
+	})
+	if channel == nil {
+		return nil, "", ircError{&irc.Message{
+			Command: irc.ERR_NOSUCHCHANNEL,
+			Params:  []string{name, "No such channel"},
+		}}
+	}
+	return channel.conn, channel.Name, nil
 }
 
 func (dc *downstreamConn) marshalNick(uc *upstreamConn, nick string) string {
@@ -274,9 +300,18 @@ func (dc *downstreamConn) handleMessageUnregistered(msg *irc.Message) error {
 }
 
 func (dc *downstreamConn) register() error {
-	u := dc.srv.getUser(strings.TrimPrefix(dc.username, "~"))
+	username := strings.TrimPrefix(dc.username, "~")
+	var network string
+	if i := strings.LastIndexAny(username, "/@"); i >= 0 {
+		network = username[i+1:]
+	}
+	if i := strings.IndexAny(username, "/@"); i >= 0 {
+		username = username[:i]
+	}
+
+	u := dc.srv.getUser(username)
 	if u == nil {
-		dc.logger.Printf("failed authentication: unknown username %q", dc.username)
+		dc.logger.Printf("failed authentication: unknown username %q", username)
 		dc.SendMessage(&irc.Message{
 			Prefix:  dc.srv.prefix(),
 			Command: irc.ERR_PASSWDMISMATCH,
@@ -285,6 +320,19 @@ func (dc *downstreamConn) register() error {
 		return nil
 	}
 
+	if network != "" {
+		dc.upstream = dc.srv.getUpstream(network)
+		if dc.upstream == nil {
+			dc.logger.Printf("failed registration: unknown upstream %q", network)
+			dc.SendMessage(&irc.Message{
+				Prefix:  dc.srv.prefix(),
+				Command: irc.ERR_PASSWDMISMATCH,
+				Params:  []string{"*", fmt.Sprintf("Unknown upstream server %q", network)},
+			})
+			return nil
+		}
+	}
+
 	dc.registered = true
 	dc.user = u
 
@@ -319,7 +367,7 @@ func (dc *downstreamConn) register() error {
 		Params:  []string{dc.nick, "No MOTD"},
 	})
 
-	u.forEachUpstream(func(uc *upstreamConn) {
+	dc.forEachUpstream(func(uc *upstreamConn) {
 		// TODO: fix races accessing upstream connection data
 		for _, ch := range uc.channels {
 			if ch.complete {
@@ -327,8 +375,7 @@ func (dc *downstreamConn) register() error {
 			}
 		}
 
-		// TODO: let clients specify the ring buffer name in their username
+		historyName := dc.username
-		historyName := ""
 
 		var seqPtr *uint64
 		if firstDownstream {
@@ -376,7 +423,7 @@ func (dc *downstreamConn) handleMessageRegistered(msg *irc.Message) error {
 			Params:  []string{dc.nick, "You may not reregister"},
 		}}
 	case "NICK":
-		dc.user.forEachUpstream(func(uc *upstreamConn) {
+		dc.forEachUpstream(func(uc *upstreamConn) {
 			uc.SendMessage(msg)
 		})
 	case "JOIN", "PART":
@@ -448,7 +495,7 @@ func (dc *downstreamConn) handleMessageRegistered(msg *irc.Message) error {
 			}
 
 			if modeStr != "" {
-				dc.user.forEachUpstream(func(uc *upstreamConn) {
+				dc.forEachUpstream(func(uc *upstreamConn) {
 					uc.SendMessage(&irc.Message{
 						Command: "MODE",
 						Params:  []string{uc.nick, modeStr},

server.go

@@ -82,13 +82,16 @@ func (u *user) forEachDownstream(f func(dc *downstreamConn)) {
 	u.lock.Unlock()
 }
 
-func (u *user) getChannel(name string) (*upstreamChannel, error) {
+func (u *user) getChannel(name string, upstream *Upstream) (*upstreamChannel, error) {
 	var channel *upstreamChannel
 	var err error
 	u.forEachUpstream(func(uc *upstreamConn) {
 		if err != nil {
 			return
 		}
+		if upstream != nil && uc.upstream != upstream {
+			return
+		}
 		if ch, ok := uc.channels[name]; ok {
 			if channel != nil {
 				err = fmt.Errorf("ambiguous channel name %q", name)
@@ -196,6 +199,15 @@ func (s *Server) getUser(name string) *user {
 	return u
 }
 
+func (s *Server) getUpstream(name string) *Upstream {
+	for i, upstream := range s.Upstreams {
+		if upstream.Addr == name {
+			return &s.Upstreams[i]
+		}
+	}
+	return nil
+}
+
 func (s *Server) Serve(ln net.Listener) error {
 	for {
 		netConn, err := ln.Accept()

upstream.go

@@ -100,6 +100,15 @@ func (uc *upstreamConn) Close() error {
 	return nil
 }
 
+func (uc *upstreamConn) forEachDownstream(f func(*downstreamConn)) {
+	uc.user.forEachDownstream(func(dc *downstreamConn) {
+		if dc.upstream != nil && dc.upstream != uc.upstream {
+			return
+		}
+		f(dc)
+	})
+}
+
 func (uc *upstreamConn) getChannel(name string) (*upstreamChannel, error) {
 	ch, ok := uc.channels[name]
 	if !ok {
@@ -140,7 +149,7 @@ func (uc *upstreamConn) handleMessage(msg *irc.Message) error {
 				return err
 			}
 
-			uc.user.forEachDownstream(func(dc *downstreamConn) {
+			uc.forEachDownstream(func(dc *downstreamConn) {
 				dc.SendMessage(&irc.Message{
 					Prefix:  dc.marshalUserPrefix(uc, msg.Prefix),
 					Command: "MODE",
@@ -210,7 +219,7 @@ func (uc *upstreamConn) handleMessage(msg *irc.Message) error {
 				ch.Members[msg.Prefix.Name] = 0
 			}
 
-			uc.user.forEachDownstream(func(dc *downstreamConn) {
+			uc.forEachDownstream(func(dc *downstreamConn) {
 				dc.SendMessage(&irc.Message{
 					Prefix:  dc.marshalUserPrefix(uc, msg.Prefix),
 					Command: "JOIN",
@@ -240,7 +249,7 @@ func (uc *upstreamConn) handleMessage(msg *irc.Message) error {
 				delete(ch.Members, msg.Prefix.Name)
 			}
 
-			uc.user.forEachDownstream(func(dc *downstreamConn) {
+			uc.forEachDownstream(func(dc *downstreamConn) {
 				dc.SendMessage(&irc.Message{
 					Prefix:  dc.marshalUserPrefix(uc, msg.Prefix),
 					Command: "PART",
@@ -326,7 +335,7 @@ func (uc *upstreamConn) handleMessage(msg *irc.Message) error {
 		}
 		ch.complete = true
 
-		uc.user.forEachDownstream(func(dc *downstreamConn) {
+		uc.forEachDownstream(func(dc *downstreamConn) {
 			forwardChannel(dc, ch)
 		})
 	case "PRIVMSG":