ether_input: Factor out ether_vlancheck()

diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index 9a74299..4f3cb3b 100644 (file)
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -1415,6 +1415,47 @@ ether_reinput_oncpu(struct ifnet *ifp, struct mbuf *m, int run_bpf)
        ether_input_oncpu(ifp, m);
 }
 
+static __inline boolean_t
+ether_vlancheck(struct mbuf **m0)
+{
+       struct mbuf *m = *m0;
+       struct ether_header *eh;
+       uint16_t ether_type;
+
+       eh = mtod(m, struct ether_header *);
+       ether_type = ntohs(eh->ether_type);
+
+       if (ether_type == ETHERTYPE_VLAN && (m->m_flags & M_VLANTAG) == 0) {
+               /*
+                * Extract vlan tag if hardware does not do it for us
+                */
+               vlan_ether_decap(&m);
+               if (m == NULL)
+                       goto failed;
+
+               eh = mtod(m, struct ether_header *);
+               ether_type = ntohs(eh->ether_type);
+       }
+
+       if (ether_type == ETHERTYPE_VLAN && (m->m_flags & M_VLANTAG)) {
+               /*
+                * To prevent possible dangerous recursion,
+                * we don't do vlan-in-vlan
+                */
+               m->m_pkthdr.rcvif->if_noproto++;
+               goto failed;
+       }
+       KKASSERT(ether_type != ETHERTYPE_VLAN);
+
+       *m0 = m;
+       return TRUE;
+failed:
+       if (m != NULL)
+               m_freem(m);
+       *m0 = NULL;
+       return FALSE;
+}
+
 static void
 ether_input_handler(struct netmsg *nmsg)
 {
@@ -1532,30 +1573,13 @@ ether_input_chain(struct ifnet *ifp, struct mbuf *m, struct mbuf_chain *chain)
                return;
        }
 
-       eh = mtod(m, struct ether_header *);
-
-       if (ntohs(eh->ether_type) == ETHERTYPE_VLAN &&
-           (m->m_flags & M_VLANTAG) == 0) {
-               /*
-                * Extract vlan tag if hardware does not do it for us
-                */
-               vlan_ether_decap(&m);
-               if (m == NULL)
-                       return;
-               eh = mtod(m, struct ether_header *);
-       }
-       ether_type = ntohs(eh->ether_type);
-
-       if ((m->m_flags & M_VLANTAG) && ether_type == ETHERTYPE_VLAN) {
-               /*
-                * To prevent possible dangerous recursion,
-                * we don't do vlan-in-vlan
-                */
-               ifp->if_noproto++;
-               m_freem(m);
+       if (!ether_vlancheck(&m)) {
+               logether(chain_end, ifp);
+               KKASSERT(m == NULL);
                return;
        }
-       KKASSERT(ether_type != ETHERTYPE_VLAN);
+       eh = mtod(m, struct ether_header *);
+       ether_type = ntohs(eh->ether_type);
 
        /*
         * Map ether type to netisr id.