move gif_encap from gif_output to gif_start.

the main win is the simplification of bpf in the ouput path.

ok visa@

diff --git a/sys/net/if_gif.c b/sys/net/if_gif.c
index d3c6a42..f613e4d 100644 (file)
--- a/sys/net/if_gif.c
+++ b/sys/net/if_gif.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_gif.c,v 1.107 2018/01/09 15:24:24 bluhm Exp $      */
+/*     $OpenBSD: if_gif.c,v 1.108 2018/01/12 02:25:27 dlg Exp $        */
 /*     $KAME: if_gif.c,v 1.43 2001/02/20 08:51:07 itojun Exp $ */
 
 /*
@@ -175,55 +175,14 @@ gif_start(struct ifnet *ifp)
 
 #if NBPFILTER > 0
                if (ifp->if_bpf) {
-                       int offset;
-                       sa_family_t family;
-                       u_int8_t proto;
-
-                       /* must decapsulate outer header for bpf */
-                       switch (sc->gif_psrc->sa_family) {
-                       case AF_INET:
-                               offset = sizeof(struct ip);
-                               proto = mtod(m, struct ip *)->ip_p;
-                               break;
-#ifdef INET6
-                       case AF_INET6:
-                               offset = sizeof(struct ip6_hdr);
-                               proto = mtod(m, struct ip6_hdr *)->ip6_nxt;
-                               break;
-#endif
-                       default:
-                               proto = 0;
-                               break;
-                       }
-                       switch (proto) {
-                       case IPPROTO_IPV4:
-                               family = AF_INET;
-                               break;
-                       case IPPROTO_IPV6:
-                               family = AF_INET6;
-                               break;
-                       case IPPROTO_ETHERIP:
-                               family = AF_LINK;
-                               offset += sizeof(struct etherip_header);
-                               break;
-                       case IPPROTO_MPLS:
-                               family = AF_MPLS;
-                               break;
-                       default:
-                               offset = 0;
-                               family = sc->gif_psrc->sa_family;
-                               break;
-                       }
-                       m->m_data += offset;
-                       m->m_len -= offset;
-                       m->m_pkthdr.len -= offset;
-                       bpf_mtap_af(ifp->if_bpf, family, m, BPF_DIRECTION_OUT);
-                       m->m_data -= offset;
-                       m->m_len += offset;
-                       m->m_pkthdr.len += offset;
+                       bpf_mtap_af(ifp->if_bpf, m->m_pkthdr.ph_family, m,
+                           BPF_DIRECTION_OUT);
                }
 #endif
 
+               if (gif_encap(ifp, &m, m->m_pkthdr.ph_family) != 0)
+                       continue;
+
                /* XXX we should cache the outgoing route */
 
                switch (sc->gif_psrc->sa_family) {
@@ -294,9 +253,7 @@ gif_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
                goto end;
        }
 
-       error = gif_encap(ifp, &m, dst->sa_family);
-       if (error)
-               goto end;
+       m->m_pkthdr.ph_family = dst->sa_family;
 
        error = if_enqueue(ifp, m);