Add channel::only_ascii_channels config option

to restrict channel names to printable ascii only.
Like disable_fake_channels this only applies to joins
by local users; unlike disable_fake_channels it applies
to opers as well.

doc/example.conf

@@ -317,6 +317,7 @@ channel {
 	no_join_on_split = no;
 	burst_topicwho = yes;
 	kick_on_split_riding = no;
+	only_ascii_channels = no;
 };
 
 serverhide {

doc/reference.conf

@@ -733,6 +733,12 @@ channel {
 	 * ratbox-services does.
 	 */
 	kick_on_split_riding = no;
+
+	/* only ascii channels: disable local users joining channels
+	 * containing characters outside the range 33-126 (non-printable
+	 * or non-ASCII).
+	 */
+	only_ascii_channels = no;
 };
 
 

include/s_conf.h

@@ -239,6 +239,7 @@ struct config_channel_entry
 	int default_split_user_count;
 	int burst_topicwho;
 	int kick_on_split_riding;
+	int only_ascii_channels;
 };
 
 struct config_server_hide

modules/core/m_join.c

@@ -990,27 +990,36 @@ do_join_0(struct Client *client_p, struct Client *source_p)
 static int
 check_channel_name_loc(struct Client *source_p, const char *name)
 {
+	const char *p;
+
 	s_assert(name != NULL);
 	if(EmptyString(name))
 		return 0;
 
 	if(ConfigFileEntry.disable_fake_channels && !IsOper(source_p))
 	{
-		for(; *name; ++name)
+		for(p = name; *p; ++p)
 		{
-			if(!IsChanChar(*name) || IsFakeChanChar(*name))
+			if(!IsChanChar(*p) || IsFakeChanChar(*p))
 				return 0;
 		}
 	}
 	else
 	{
-		for(; *name; ++name)
+		for(p = name; *p; ++p)
 		{
-			if(!IsChanChar(*name))
+			if(!IsChanChar(*p))
 				return 0;
 		}
 	}
 
+	if(ConfigChannel.only_ascii_channels)
+	{
+		for(p = name; *p; ++p)
+			if(*p < 33 || *p > 126)
+				return 0;
+	}
+
 	return 1;
 }
 

modules/m_info.c

@@ -542,6 +542,12 @@ static struct InfoStruct info_table[] = {
 		&ConfigChannel.no_join_on_split,
 		"Disallow joining channels when split",
 	},
+	{
+		"only_ascii_channels",
+		OUTPUT_BOOLEAN_YN,
+		&ConfigChannel.only_ascii_channels,
+		"Controls whether non-ASCII is disabled for JOIN"
+	},
 	{
 		"use_except",
 		OUTPUT_BOOLEAN_YN,

src/newconf.c

@@ -2187,6 +2187,7 @@ static struct ConfEntry conf_channel_table[] =
 	{ "max_chans_per_user", CF_INT,   NULL, 0, &ConfigChannel.max_chans_per_user 	},
 	{ "no_create_on_split", CF_YESNO, NULL, 0, &ConfigChannel.no_create_on_split 	},
 	{ "no_join_on_split",	CF_YESNO, NULL, 0, &ConfigChannel.no_join_on_split	},
+	{ "only_ascii_channels", CF_YESNO, NULL, 0, &ConfigChannel.only_ascii_channels },
 	{ "use_except",		CF_YESNO, NULL, 0, &ConfigChannel.use_except		},
 	{ "use_invex",		CF_YESNO, NULL, 0, &ConfigChannel.use_invex		},
 	{ "use_knock",		CF_YESNO, NULL, 0, &ConfigChannel.use_knock		},

src/s_conf.c

@@ -811,6 +811,7 @@ set_default_conf(void)
 	ConfigChannel.max_chans_per_user = 15;
 	ConfigChannel.max_bans = 25;
 	ConfigChannel.max_bans_large = 500;
+	ConfigChannel.only_ascii_channels = NO;
 	ConfigChannel.burst_topicwho = NO;
 	ConfigChannel.kick_on_split_riding = NO;