From dfeba6556304bc6ee712b484a9730cf998d4a4d7 Mon Sep 17 00:00:00 2001
From: Ed Kellett <e@kellett.im>
Date: Sat, 24 Apr 2021 12:15:20 +0100
Subject: [PATCH] Add channel::ip_bans_through_vhost

---
 doc/reference.conf | 3 +++
 include/s_conf.h   | 1 +
 ircd/match.c       | 6 ++++--
 ircd/newconf.c     | 1 +
 ircd/s_conf.c      | 1 +
 modules/m_info.c   | 5 +++++
 6 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/doc/reference.conf b/doc/reference.conf
index 4bfd49f5..702e4325 100644
--- a/doc/reference.conf
+++ b/doc/reference.conf
@@ -794,6 +794,9 @@ channel {
 	 * as PRIVMSG @#channel when sent to clients.
 	 */
 	opmod_send_statusmsg = no;
+
+	/* ip_bans_through_vhost: should channel IP bans see through dynamic spoofed hosts? */
+	ip_bans_through_vhost = yes;
 };
 
 
diff --git a/include/s_conf.h b/include/s_conf.h
index 8f7a1855..ae1ef15e 100644
--- a/include/s_conf.h
+++ b/include/s_conf.h
@@ -285,6 +285,7 @@ struct config_channel_entry
 	int displayed_usercount;
 	int strip_topic_colors;
 	int opmod_send_statusmsg;
+	int ip_bans_through_vhost;
 };
 
 struct config_server_hide
diff --git a/ircd/match.c b/ircd/match.c
index 38641866..429387ca 100644
--- a/ircd/match.c
+++ b/ircd/match.c
@@ -22,6 +22,7 @@
 #include "client.h"
 #include "ircd.h"
 #include "match.h"
+#include "s_conf.h"
 #include "s_assert.h"
 
 /*
@@ -622,6 +623,7 @@ int ircncmp(const char *s1, const char *s2, int n)
 
 void matchset_for_client(struct Client *who, struct matchset *m)
 {
+	bool hide_ip = IsIPSpoof(who) || (!ConfigChannel.ip_bans_through_vhost && IsDynSpoof(who));
 	unsigned hostn = 0;
 	unsigned ipn = 0;
 
@@ -629,7 +631,7 @@ void matchset_for_client(struct Client *who, struct matchset *m)
 
 	sprintf(m->host[hostn++], "%s!%s@%s", who->name, who->username, who->host);
 
-	if (!IsIPSpoof(who))
+	if (!hide_ip)
 	{
 		sprintf(m->ip[ipn++], "%s!%s@%s", who->name, who->username, who->sockhost);
 	}
@@ -648,7 +650,7 @@ void matchset_for_client(struct Client *who, struct matchset *m)
 			sprintf(m->host[hostn++], "%s!%s@%s", who->name, who->username, who->localClient->mangledhost);
 		}
 	}
-	if (!IsIPSpoof(who) && GET_SS_FAMILY(&who->localClient->ip) == AF_INET6 &&
+	if (!hide_ip && GET_SS_FAMILY(&who->localClient->ip) == AF_INET6 &&
 			rb_ipv4_from_ipv6((const struct sockaddr_in6 *)&who->localClient->ip, &ip4))
 	{
 		int n = sprintf(m->ip[ipn++], "%s!%s@", who->name, who->username);
diff --git a/ircd/newconf.c b/ircd/newconf.c
index b9a329c9..22cc983b 100644
--- a/ircd/newconf.c
+++ b/ircd/newconf.c
@@ -2744,6 +2744,7 @@ static struct ConfEntry conf_channel_table[] =
 	{ "displayed_usercount",	CF_INT, NULL, 0, &ConfigChannel.displayed_usercount	},
 	{ "strip_topic_colors",	CF_YESNO, NULL, 0, &ConfigChannel.strip_topic_colors	},
 	{ "opmod_send_statusmsg", CF_YESNO, NULL, 0, &ConfigChannel.opmod_send_statusmsg	},
+	{ "ip_bans_through_vhost", CF_YESNO, NULL, 0, &ConfigChannel.ip_bans_through_vhost	},
 	{ "\0", 		0, 	  NULL, 0, NULL }
 };
 
diff --git a/ircd/s_conf.c b/ircd/s_conf.c
index c84047e4..a35d64a8 100644
--- a/ircd/s_conf.c
+++ b/ircd/s_conf.c
@@ -808,6 +808,7 @@ set_default_conf(void)
 	ConfigChannel.disable_local_channels = false;
 	ConfigChannel.displayed_usercount = 3;
 	ConfigChannel.opmod_send_statusmsg = false;
+	ConfigChannel.ip_bans_through_vhost= true;
 
 	ConfigChannel.autochanmodes = MODE_TOPICLIMIT | MODE_NOPRIVMSGS;
 
diff --git a/modules/m_info.c b/modules/m_info.c
index 11ab1db9..d1b286f6 100644
--- a/modules/m_info.c
+++ b/modules/m_info.c
@@ -581,6 +581,11 @@ static struct InfoStruct info_table[] = {
 		"Send messages to @#channel if affected by +z",
 		INFO_INTBOOL_YN(&ConfigChannel.opmod_send_statusmsg),
 	},
+	{
+		"ip_bans_through_vhost",
+		"Channel IP bans see through dynamic spoofs",
+		INFO_INTBOOL_YN(&ConfigChannel.ip_bans_through_vhost),
+	},
 	{
 		"hide_opers",
 		"Hide all opers from unprivileged users",