fix #964

conventional.yaml

@@ -491,6 +491,10 @@ channels:
         # how many channels can each account register?
         max-channels-per-account: 15
 
+    # as a crude countermeasure against spambots, connections younger than this value
+    # will get an empty response to /LIST (a time period of 0 disables)
+    list-delay: 0s
+
 # operator classes
 oper-classes:
     # local operator

irc/config.go

@@ -550,6 +550,7 @@ type Config struct {
 			OperatorOnly          bool `yaml:"operator-only"`
 			MaxChannelsPerAccount int  `yaml:"max-channels-per-account"`
 		}
+		ListDelay time.Duration `yaml:"list-delay"`
 	}
 
 	OperClasses map[string]*OperClassConfig `yaml:"oper-classes"`

irc/handlers.go

@@ -1408,6 +1408,14 @@ func languageHandler(server *Server, client *Client, msg ircmsg.IrcMessage, rb *
 
 // LIST [<channel>{,<channel>}] [<elistcond>{,<elistcond>}]
 func listHandler(server *Server, client *Client, msg ircmsg.IrcMessage, rb *ResponseBuffer) bool {
+	config := server.Config()
+	if time.Since(client.ctime) < config.Channels.ListDelay && client.Account() == "" {
+		remaining := time.Until(client.ctime.Add(config.Channels.ListDelay))
+		csNotice(rb, fmt.Sprintf(client.t("This server requires that you wait %v after connecting before you can use /LIST. You have %v left."), config.Channels.ListDelay, remaining))
+		rb.Add(nil, server.name, RPL_LISTEND, client.nick, client.t("End of LIST"))
+		return false
+	}
+
 	// get channels
 	var channels []string
 	for _, param := range msg.Params {

oragono.yaml

@@ -512,6 +512,10 @@ channels:
         # how many channels can each account register?
         max-channels-per-account: 15
 
+    # as a crude countermeasure against spambots, connections younger than this value
+    # will get an empty response to /LIST (a time period of 0 disables)
+    list-delay: 0s
+
 # operator classes
 oper-classes:
     # local operator