[src/netbsd-8]: src/sys Pull up following revision(s) (requested by roy in ti...

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

details:   https://anonhg.NetBSD.org/src/rev/9b5a2ab067f6
branches:  netbsd-8
changeset: 850778:9b5a2ab067f6
user:      snj <snj%NetBSD.org@localhost>
date:      Sat Jul 01 08:56:06 2017 +0000

description:
Pull up following revision(s) (requested by roy in ticket #77):
        sys/net/if.h: revision 1.240
        sys/netinet/if_arp.c: revision 1.253
        sys/net/if.c: revision 1.395
Introduce if_get_bylla to find an interface with the active
local link address.
--
Use if_get_bylla() instead of just looking at the lla of the interface
the address belongs to.
This allows any ARP message we receieved from another interface to
be correctly dropped.
While here, move the protocol length check higher up the food chain.

diffstat:

 sys/net/if.c         |  31 +++++++++++++++++++++++++++----
 sys/net/if.h         |   3 ++-
 sys/netinet/if_arp.c |  23 ++++++++++++-----------
 3 files changed, 41 insertions(+), 16 deletions(-)

diffs (134 lines):

diff -r c9f494004ce4 -r 9b5a2ab067f6 sys/net/if.c
--- a/sys/net/if.c      Sat Jul 01 08:54:08 2017 +0000
+++ b/sys/net/if.c      Sat Jul 01 08:56:06 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if.c,v 1.394 2017/06/01 02:45:14 chs Exp $     */
+/*     $NetBSD: if.c,v 1.394.2.1 2017/07/01 08:56:06 snj Exp $ */
 
 /*-
  * Copyright (c) 1999, 2000, 2001, 2008 The NetBSD Foundation, Inc.
@@ -90,7 +90,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if.c,v 1.394 2017/06/01 02:45:14 chs Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if.c,v 1.394.2.1 2017/07/01 08:56:06 snj Exp $");
 
 #if defined(_KERNEL_OPT)
 #include "opt_inet.h"
@@ -2599,8 +2599,8 @@
 }
 
 /*
- * Release a reference of an ifnet object given by if_get or
- * if_get_byindex.
+ * Release a reference of an ifnet object given by if_get, if_get_byindex
+ * or if_get_bylla.
  */
 void
 if_put(const struct ifnet *ifp, struct psref *psref)
@@ -2643,6 +2643,29 @@
        return ifp;
 }
 
+ifnet_t *
+if_get_bylla(const void *lla, unsigned char lla_len, struct psref *psref)
+{
+       ifnet_t *ifp;
+       int s;
+
+       s = pserialize_read_enter();
+       IFNET_READER_FOREACH(ifp) {
+               if (if_is_deactivated(ifp))
+                       continue;
+               if (ifp->if_addrlen != lla_len)
+                       continue;
+               if (memcmp(lla, CLLADDR(ifp->if_sadl), lla_len) == 0) {
+                       psref_acquire(psref, &ifp->if_psref,
+                           ifnet_psref_class);
+                       break;
+               }
+       }
+       pserialize_read_exit(s);
+
+       return ifp;
+}
+
 /*
  * Note that it's safe only if the passed ifp is guaranteed to not be freed,
  * for example using pserialize or the ifp is already held or some other
diff -r c9f494004ce4 -r 9b5a2ab067f6 sys/net/if.h
--- a/sys/net/if.h      Sat Jul 01 08:54:08 2017 +0000
+++ b/sys/net/if.h      Sat Jul 01 08:56:06 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if.h,v 1.239 2017/05/19 08:53:51 ozaki-r Exp $ */
+/*     $NetBSD: if.h,v 1.239.2.1 2017/07/01 08:56:06 snj Exp $ */
 
 /*-
  * Copyright (c) 1999, 2000, 2001 The NetBSD Foundation, Inc.
@@ -974,6 +974,7 @@
 struct ifnet *if_get(const char *, struct psref *);
 ifnet_t *if_byindex(u_int);
 ifnet_t *if_get_byindex(u_int, struct psref *);
+ifnet_t *if_get_bylla(const void *, unsigned char, struct psref *);
 void   if_put(const struct ifnet *, struct psref *);
 void   if_acquire(struct ifnet *, struct psref *);
 #define        if_release      if_put
diff -r c9f494004ce4 -r 9b5a2ab067f6 sys/netinet/if_arp.c
--- a/sys/netinet/if_arp.c      Sat Jul 01 08:54:08 2017 +0000
+++ b/sys/netinet/if_arp.c      Sat Jul 01 08:56:06 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_arp.c,v 1.250 2017/05/18 06:33:11 ozaki-r Exp $     */
+/*     $NetBSD: if_arp.c,v 1.250.2.1 2017/07/01 08:56:06 snj Exp $     */
 
 /*-
  * Copyright (c) 1998, 2000, 2008 The NetBSD Foundation, Inc.
@@ -68,7 +68,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.250 2017/05/18 06:33:11 ozaki-r Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.250.2.1 2017/07/01 08:56:06 snj Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_ddb.h"
@@ -1020,6 +1020,16 @@
        ah = mtod(m, struct arphdr *);
        op = ntohs(ah->ar_op);
 
+       if (ah->ar_pln != sizeof(struct in_addr))
+               goto out;
+
+       ifp = if_get_bylla(ar_sha(ah), ah->ar_hln, &psref);
+       if (ifp) {
+               if_put(ifp, &psref);
+               ARP_STATINC(ARP_STAT_RCVLOCALSHA);
+               goto out;       /* it's from me, ignore it. */
+       }
+
        rcvif = ifp = m_get_rcvif_psref(m, &psref);
        if (__predict_false(rcvif == NULL))
                goto drop;
@@ -1041,9 +1051,6 @@
                break;
        }
 
-       if (ah->ar_pln != sizeof(struct in_addr))
-               goto drop;
-
        memcpy(&isaddr, ar_spa(ah), sizeof(isaddr));
        memcpy(&itaddr, ar_tpa(ah), sizeof(itaddr));
 
@@ -1130,12 +1137,6 @@
        myaddr = ia->ia_addr.sin_addr;
 
        /* XXX checks for bridge case? */
-       if (!memcmp(ar_sha(ah), CLLADDR(ifp->if_sadl), ifp->if_addrlen)) {
-               ARP_STATINC(ARP_STAT_RCVLOCALSHA);
-               goto out;       /* it's from me, ignore it. */
-       }
-
-       /* XXX checks for bridge case? */
        if (!memcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) {
                ARP_STATINC(ARP_STAT_RCVBCASTSHA);
                log(LOG_ERR,