Restrict ident length similar to other servers

irc/client.go

@@ -176,12 +176,12 @@ func NewClient(server *Server, conn net.Conn, isTLS bool) {
 		client.Notice(client.t("*** Looking up your username"))
 		resp, err := ident.Query(clientHost, serverPort, clientPort, IdentTimeoutSeconds)
 		if err == nil {
-			username := resp.Identifier
-			cfusername, err := CasefoldName(username)
-			if err == nil {
+			ident := resp.Identifier[:config.Limits.IdentLen-1]
+			if isIdent(ident) {
+				identLower := strings.ToLower(ident) // idents can only be ASCII chars only
 				client.Notice(client.t("*** Found your username"))
-				client.username = username
-				client.usernameCasefolded = cfusername
+				client.username = ident
+				client.usernameCasefolded = identLower
 				// we don't need to updateNickMask here since nickMask is not used for anything yet
 			} else {
 				client.Notice(client.t("*** Got a malformed username, ignoring"))

irc/config.go

@@ -206,12 +206,13 @@ type Limits struct {
 	AwayLen        int           `yaml:"awaylen"`
 	ChanListModes  int           `yaml:"chan-list-modes"`
 	ChannelLen     int           `yaml:"channellen"`
+	IdentLen       int           `yaml:"identlen"`
 	KickLen        int           `yaml:"kicklen"`
+	LineLen        LineLenLimits `yaml:"linelen"`
 	MonitorEntries int           `yaml:"monitor-entries"`
 	NickLen        int           `yaml:"nicklen"`
 	TopicLen       int           `yaml:"topiclen"`
 	WhowasEntries  int           `yaml:"whowas-entries"`
-	LineLen        LineLenLimits `yaml:"linelen"`
 }
 
 // STSConfig controls the STS configuration/
@@ -491,6 +492,10 @@ func LoadConfig(filename string) (config *Config, err error) {
 	if len(config.Server.Listen) == 0 {
 		return nil, ErrNoListenersDefined
 	}
+	//dan: automagically fix identlen until a few releases in the future (from now, 0.12.0), being a newly-introduced limit
+	if config.Limits.IdentLen < 1 {
+		config.Limits.IdentLen = 10
+	}
 	if config.Limits.NickLen < 1 || config.Limits.ChannelLen < 2 || config.Limits.AwayLen < 1 || config.Limits.KickLen < 1 || config.Limits.TopicLen < 1 {
 		return nil, ErrLimitsAreInsane
 	}

irc/handlers.go

@@ -2193,7 +2193,9 @@ func userHandler(server *Server, client *Client, msg ircmsg.IrcMessage, rb *Resp
 		return false
 	}
 
-	err := client.SetNames(msg.Params[0], msg.Params[3])
+	ident := msg.Params[0][:server.Limits().IdentLen-1] // -1 as SetNames adds the ~ at the start for us
+
+	err := client.SetNames(ident, msg.Params[3])
 	if err == errInvalidUsername {
 		rb.Add(nil, server.name, ERR_INVALIDUSERNAME, client.t("Malformed username"))
 	}

oragono.yaml

@@ -415,6 +415,9 @@ limits:
     # nicklen is the max nick length allowed
     nicklen: 32
 
+    # identlen is the max ident length allowed
+    identlen: 10
+
     # channellen is the max channel length allowed
     channellen: 64