When an interface doesn't have a layer 2 address in6_get_soii_ifid()

failes and then later on a in in6_get_ifid() a layer 2 address is
"borrowed" from from another interface.

Do the "borrowing" in in6_get_soii_ifid(), too so that semantically
opaque interface identifiers work for these kind of interfaces, too.

OK phessler, benno

diff --git a/sys/netinet6/in6_ifattach.c b/sys/netinet6/in6_ifattach.c
index 9aea226..7ea489a 100644 (file)
--- a/sys/netinet6/in6_ifattach.c
+++ b/sys/netinet6/in6_ifattach.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: in6_ifattach.c,v 1.108 2018/07/10 20:43:26 florian Exp $      */
+/*     $OpenBSD: in6_ifattach.c,v 1.109 2018/07/10 20:44:39 florian Exp $      */
 /*     $KAME: in6_ifattach.c,v 1.124 2001/07/18 08:32:51 jinmei Exp $  */
 
 /*
@@ -216,8 +216,9 @@ in6_get_hw_ifid(struct ifnet *ifp, struct in6_addr *in6)
  * in6 - upper 64bits are preserved
  */
 int
-in6_get_soii_ifid(struct ifnet *ifp, struct in6_addr *in6)
+in6_get_soii_ifid(struct ifnet *ifp0, struct in6_addr *in6)
 {
+       struct ifnet *ifp;
        SHA2_CTX ctx;
        u_int8_t digest[SHA512_DIGEST_LENGTH];
        struct in6_addr prefix;
@@ -225,10 +226,25 @@ in6_get_soii_ifid(struct ifnet *ifp, struct in6_addr *in6)
        int dad_counter = 0; /* XXX not used */
        char *addr;
 
-       if (ifp->if_xflags & IFXF_INET6_NOSOII)
+       if (ifp0->if_xflags & IFXF_INET6_NOSOII)
                return -1;
 
-       sdl = ifp->if_sadl;
+       sdl = ifp0->if_sadl;
+
+       if (sdl == NULL || sdl->sdl_alen == 0) {
+               /*
+                * try to get it from some other hardware interface like
+                * in in6_get_ifid()
+                */
+               TAILQ_FOREACH(ifp, &ifnet, if_list) {
+                       if (ifp == ifp0)
+                               continue;
+                       sdl = ifp->if_sadl;
+                       if (sdl != NULL && sdl->sdl_alen != 0)
+                               break;
+               }
+       }
+
        if (sdl == NULL || sdl->sdl_alen == 0)
                return -1;