diff mbox series

[Openvpn-devel,v4] Remove unused function check_subnet_conflict

Message ID 20250309165500.21796-1-gert@greenie.muc.de
State New
Headers show
Series [Openvpn-devel,v4] Remove unused function check_subnet_conflict | expand

Commit Message

Gert Doering March 9, 2025, 4:55 p.m. UTC 
From: Frank Lichtenheld <frank@lichtenheld.com>

This has been #if 0 for over a decade. Let's just
remove this.

Change-Id: If570253e57371e4126b0e8aa4c349e2051cb8b00
Signed-off-by: Frank Lichtenheld <frank@lichtenheld.com>
Acked-by: Gert Doering <gert@greenie.muc.de>
---

This change was reviewed on Gerrit and approved by at least one
developer. I request to merge it to master.

Gerrit URL: https://gerrit.openvpn.net/c/openvpn/+/863
This mail reflects revision 4 of this Change.

Acked-by according to Gerrit (reflected above):
Gert Doering <gert@greenie.muc.de>

Comments

Gert Doering March 9, 2025, 5:01 p.m. UTC | #1 
Haven't tested this (beyond "does it compile") as there is not much to
test - the function called is completely #if 0'ed, and there are no side
effects in the calls.

I'm a bit sad to see it go (the idea behind it is useful), but it did not
work the way it was written, was not adjusted to recent updates, and should
propably need to take IPv6 into account - so quite a project.  But if
someone wants to bring it back and make it useful, be by guest ;-)

Your patch has been applied to the master branch.

commit 536809792da2e4f540015f032ab656680021be03
Author: Frank Lichtenheld
Date:   Sun Mar 9 17:55:00 2025 +0100

     Remove unused function check_subnet_conflict

     Signed-off-by: Frank Lichtenheld <frank@lichtenheld.com>
     Acked-by: Gert Doering <gert@greenie.muc.de>
     Message-Id: <20250309165500.21796-1-gert@greenie.muc.de>
     URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg31083.html
     Signed-off-by: Gert Doering <gert@greenie.muc.de>


--
kind regards,

Gert Doering
diff mbox series

Patch

diff --git a/src/openvpn/route.c b/src/openvpn/route.c
index 245b15b..dbdc01d 100644
--- a/src/openvpn/route.c
+++ b/src/openvpn/route.c
@@ -1218,7 +1218,6 @@ 
 
         for (r = rl->routes; r; r = r->next)
         {
-            check_subnet_conflict(r->network, r->netmask, "route");
             if (flags & ROUTE_DELETE_FIRST)
             {
                 delete_route(r, tt, flags, &rl->rgi, es, ctx);
diff --git a/src/openvpn/tun.c b/src/openvpn/tun.c
index 4817f45..de54e89 100644
--- a/src/openvpn/tun.c
+++ b/src/openvpn/tun.c
@@ -626,44 +626,6 @@ 
     gc_free(&gc);
 }
 
-/*
- * Issue a warning if ip/netmask (on the virtual IP network) conflicts with
- * the settings on the local LAN.  This is designed to flag issues where
- * (for example) the OpenVPN server LAN is running on 192.168.1.x, but then
- * an OpenVPN client tries to connect from a public location that is also running
- * off of a router set to 192.168.1.x.
- */
-void
-check_subnet_conflict(const in_addr_t ip,
-                      const in_addr_t netmask,
-                      const char *prefix)
-{
-#if 0 /* too many false positives */
-    struct gc_arena gc = gc_new();
-    in_addr_t lan_gw = 0;
-    in_addr_t lan_netmask = 0;
-
-    if (get_default_gateway(&lan_gw, &lan_netmask) && lan_netmask)
-    {
-        const in_addr_t lan_network = lan_gw & lan_netmask;
-        const in_addr_t network = ip & netmask;
-
-        /* do the two subnets defined by network/netmask and lan_network/lan_netmask intersect? */
-        if ((network & lan_netmask) == lan_network
-            || (lan_network & netmask) == network)
-        {
-            msg(M_WARN, "WARNING: potential %s subnet conflict between local LAN [%s/%s] and remote VPN [%s/%s]",
-                prefix,
-                print_in_addr_t(lan_network, 0, &gc),
-                print_in_addr_t(lan_netmask, 0, &gc),
-                print_in_addr_t(network, 0, &gc),
-                print_in_addr_t(netmask, 0, &gc));
-        }
-    }
-    gc_free(&gc);
-#endif /* if 0 */
-}
-
 void
 warn_on_use_of_common_subnets(openvpn_net_ctx_t *ctx)
 {
@@ -922,15 +884,6 @@ 
                                      tt->remote_netmask);
                 }
             }
-
-            if (!tun_p2p)
-            {
-                check_subnet_conflict(tt->local, tt->remote_netmask, "TUN/TAP adapter");
-            }
-            else
-            {
-                check_subnet_conflict(tt->local, IPV4_NETMASK_HOST, "TUN/TAP adapter");
-            }
         }
 
 #ifdef _WIN32
diff --git a/src/openvpn/tun.h b/src/openvpn/tun.h
index ccba0bc..b616f5d 100644
--- a/src/openvpn/tun.h
+++ b/src/openvpn/tun.h
@@ -355,10 +355,6 @@ 
 
 bool is_tun_p2p(const struct tuntap *tt);
 
-void check_subnet_conflict(const in_addr_t ip,
-                           const in_addr_t netmask,
-                           const char *prefix);
-
 void warn_on_use_of_common_subnets(openvpn_net_ctx_t *ctx);
 
 /**