[src/netbsd-8]: src/sys/net Pull up following revision(s) (requested by tih i...

[martin <martin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/5549100abb00
branches:  netbsd-8
changeset: 851489:5549100abb00
user:      martin <martin%NetBSD.org@localhost>
date:      Sat Mar 17 11:26:44 2018 +0000

description:
Pull up following revision(s) (requested by tih in ticket #638):
        sys/net/if_tun.c: revision 1.143

Add packet filtering to tun(4) interfaces.

Calls to pfil_run_hooks() were missing in if_tun.c.  This meant that
filtering configuration could be added to e.g. /etc/npf.conf, but
would be ignored, because the filter never saw the packets.  This
change adds the required calls.

While here, correct the return value from tun_output(): it's been
returning 0 regardless of any error condition present, but will now
correctly propagate such information upward.

Thanks to maxv for guidance!
OK: christos, martin

diffstat:

 sys/net/if_tun.c |  20 +++++++++++++++-----
 1 files changed, 15 insertions(+), 5 deletions(-)

diffs (56 lines):

diff -r a3bf2de55c71 -r 5549100abb00 sys/net/if_tun.c
--- a/sys/net/if_tun.c  Sat Mar 17 11:23:18 2018 +0000
+++ b/sys/net/if_tun.c  Sat Mar 17 11:26:44 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_tun.c,v 1.139.2.2 2018/01/02 10:20:33 snj Exp $     */
+/*     $NetBSD: if_tun.c,v 1.139.2.3 2018/03/17 11:26:44 martin Exp $  */
 
 /*
  * Copyright (c) 1988, Julian Onions <jpo%cs.nott.ac.uk@localhost>
@@ -19,7 +19,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_tun.c,v 1.139.2.2 2018/01/02 10:20:33 snj Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_tun.c,v 1.139.2.3 2018/03/17 11:26:44 martin Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_inet.h"
@@ -555,6 +555,11 @@
 
        bpf_mtap_af(ifp, dst->sa_family, m0);
 
+       if ((error = pfil_run_hooks(ifp->if_pfil, &m0, ifp, PFIL_OUT)) != 0)
+               goto out;
+       if (m0 == NULL)
+               goto out;
+
        switch(dst->sa_family) {
 #ifdef INET6
        case AF_INET6:
@@ -624,10 +629,10 @@
 
        mutex_exit(&tp->tun_lock);
 out:
-       if (error && m0) {
+       if (error && m0)
                m_freem(m0);
-       }
-       return 0;
+
+       return error;
 }
 
 static void
@@ -941,6 +946,11 @@
 
        bpf_mtap_af(ifp, dst.sa_family, top);
 
+       if ((error = pfil_run_hooks(ifp->if_pfil, &top, ifp, PFIL_IN)) != 0)
+               goto out0;
+       if (top == NULL)
+               goto out0;
+
        mutex_enter(&tp->tun_lock);
        if ((tp->tun_flags & TUN_INITED) == 0) {
                /* Interface was destroyed */