I preparation for TSO in software, cleanup the fragment code. Use

if_output_ml() to send mbuf lists to interfaces.  This can be used
for TSO, fragments, ARP and ND6.  Rename variable fml to ml.  In
pf_route6() split the if else block.  Put the safety check (hlen +
firstlen < tlen) into ip_fragment().  It makes the code correct in
case the packet is too short to be fragmented.  This should not
happen, but other functions also have this logic.
No functional change.  OK sashan@

diff --git a/sys/net/if.c b/sys/net/if.c
index 4534ed5..e9ea77f 100644 (file)
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if.c,v 1.694 2023/04/26 19:54:35 mvs Exp $    */
+/*     $OpenBSD: if.c,v 1.695 2023/05/07 16:23:23 bluhm Exp $  */
 /*     $NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $  */
 
 /*
@@ -761,27 +761,6 @@ if_enqueue_ifq(struct ifnet *ifp, struct mbuf *m)
        return (0);
 }
 
-void
-if_mqoutput(struct ifnet *ifp, struct mbuf_queue *mq, unsigned int *total,
-    struct sockaddr *dst, struct rtentry *rt)
-{
-       struct mbuf_list ml;
-       struct mbuf *m;
-       unsigned int len;
-
-       mq_delist(mq, &ml);
-       len = ml_len(&ml);
-       while ((m = ml_dequeue(&ml)) != NULL)
-               ifp->if_output(ifp, m, rt_key(rt), rt);
-
-       /* XXXSMP we also discard if other CPU enqueues */
-       if (mq_len(mq) > 0) {
-               /* mbuf is back in queue. Discard. */
-               atomic_sub_int(total, len + mq_purge(mq));
-       } else
-               atomic_sub_int(total, len);
-}
-
 void
 if_input(struct ifnet *ifp, struct mbuf_list *ml)
 {
@@ -843,6 +822,46 @@ if_input_local(struct ifnet *ifp, struct mbuf *m, sa_family_t af)
        return (0);
 }
 
+int
+if_output_ml(struct ifnet *ifp, struct mbuf_list *ml,
+    struct sockaddr *dst, struct rtentry *rt)
+{
+       struct mbuf *m;
+       int error = 0;
+
+       while ((m = ml_dequeue(ml)) != NULL) {
+               error = ifp->if_output(ifp, m, dst, rt);
+               if (error)
+                       break;
+       }
+       if (error)
+               ml_purge(ml);
+
+       return error;
+}
+
+int
+if_output_mq(struct ifnet *ifp, struct mbuf_queue *mq, unsigned int *total,
+    struct sockaddr *dst, struct rtentry *rt)
+{
+       struct mbuf_list ml;
+       unsigned int len;
+       int error;
+
+       mq_delist(mq, &ml);
+       len = ml_len(&ml);
+       error = if_output_ml(ifp, &ml, dst, rt);
+
+       /* XXXSMP we also discard if other CPU enqueues */
+       if (mq_len(mq) > 0) {
+               /* mbuf is back in queue. Discard. */
+               atomic_sub_int(total, len + mq_purge(mq));
+       } else
+               atomic_sub_int(total, len);
+
+       return error;
+}
+
 int
 if_output_local(struct ifnet *ifp, struct mbuf *m, sa_family_t af)
 {

diff --git a/sys/net/if_bridge.c b/sys/net/if_bridge.c
index a202556..463ca9c 100644 (file)
--- a/sys/net/if_bridge.c
+++ b/sys/net/if_bridge.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_bridge.c,v 1.365 2023/02/27 09:35:32 jan Exp $     */
+/*     $OpenBSD: if_bridge.c,v 1.366 2023/05/07 16:23:23 bluhm Exp $   */
 
 /*
  * Copyright (c) 1999, 2000 Jason L. Wright (jason@thought.net)
@@ -1826,7 +1826,7 @@ bridge_fragment(struct ifnet *brifp, struct ifnet *ifp, struct ether_header *eh,
     struct mbuf *m)
 {
        struct llc llc;
-       struct mbuf_list fml;
+       struct mbuf_list ml;
        int error = 0;
        int hassnap = 0;
        u_int16_t etype;
@@ -1884,11 +1884,11 @@ bridge_fragment(struct ifnet *brifp, struct ifnet *ifp, struct ether_header *eh,
                return;
        }
 
-       error = ip_fragment(m, &fml, ifp, ifp->if_mtu);
+       error = ip_fragment(m, &ml, ifp, ifp->if_mtu);
        if (error)
                return;
 
-       while ((m = ml_dequeue(&fml)) != NULL) {
+       while ((m = ml_dequeue(&ml)) != NULL) {
                if (hassnap) {
                        M_PREPEND(m, LLC_SNAPFRAMELEN, M_DONTWAIT);
                        if (m == NULL) {
@@ -1908,7 +1908,7 @@ bridge_fragment(struct ifnet *brifp, struct ifnet *ifp, struct ether_header *eh,
                        break;
        }
        if (error)
-               ml_purge(&fml);
+               ml_purge(&ml);
        else
                ipstat_inc(ips_fragmented);
 

diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 853dbcc..94480ac 100644 (file)
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_var.h,v 1.125 2023/04/18 22:01:24 mvs Exp $        */
+/*     $OpenBSD: if_var.h,v 1.126 2023/05/07 16:23:23 bluhm Exp $      */
 /*     $NetBSD: if.h,v 1.23 1996/05/07 02:40:27 thorpej Exp $  */
 
 /*
@@ -321,12 +321,14 @@ extern struct ifnet_head ifnetlist;
 void   if_start(struct ifnet *);
 int    if_enqueue(struct ifnet *, struct mbuf *);
 int    if_enqueue_ifq(struct ifnet *, struct mbuf *);
-void   if_mqoutput(struct ifnet *, struct mbuf_queue *, unsigned int *,
-           struct sockaddr *, struct rtentry *);
 void   if_input(struct ifnet *, struct mbuf_list *);
 void   if_vinput(struct ifnet *, struct mbuf *);
 void   if_input_process(struct ifnet *, struct mbuf_list *);
 int    if_input_local(struct ifnet *, struct mbuf *, sa_family_t);
+int    if_output_ml(struct ifnet *, struct mbuf_list *,
+           struct sockaddr *, struct rtentry *);
+int    if_output_mq(struct ifnet *, struct mbuf_queue *, unsigned int *,
+           struct sockaddr *, struct rtentry *);
 int    if_output_local(struct ifnet *, struct mbuf *, sa_family_t);
 void   if_rtrequest_dummy(struct ifnet *, int, struct rtentry *);
 void   p2p_rtrequest(struct ifnet *, int, struct rtentry *);

diff --git a/sys/net/pf.c b/sys/net/pf.c
index 56739a2..e98bda1 100644 (file)
--- a/sys/net/pf.c
+++ b/sys/net/pf.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: pf.c,v 1.1175 2023/05/03 10:32:47 kn Exp $ */
+/*     $OpenBSD: pf.c,v 1.1176 2023/05/07 16:23:23 bluhm Exp $ */
 
 /*
  * Copyright (c) 2001 Daniel Hartmeier
@@ -6466,12 +6466,11 @@ void
 pf_route(struct pf_pdesc *pd, struct pf_state *st)
 {
        struct mbuf             *m0;
-       struct mbuf_list         fml;
+       struct mbuf_list         ml;
        struct sockaddr_in      *dst, sin;
        struct rtentry          *rt = NULL;
        struct ip               *ip;
        struct ifnet            *ifp = NULL;
-       int                      error = 0;
        unsigned int             rtableid;
 
        if (pd->m->m_pkthdr.pf.routed++ > 3) {
@@ -6559,7 +6558,7 @@ pf_route(struct pf_pdesc *pd, struct pf_state *st)
                        ipstat_inc(ips_outswcsum);
                        ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);
                }
-               error = ifp->if_output(ifp, m0, sintosa(dst), rt);
+               ifp->if_output(ifp, m0, sintosa(dst), rt);
                goto done;
        }
 
@@ -6575,19 +6574,10 @@ pf_route(struct pf_pdesc *pd, struct pf_state *st)
                goto bad;
        }
 
-       error = ip_fragment(m0, &fml, ifp, ifp->if_mtu);
-       if (error)
+       if (ip_fragment(m0, &ml, ifp, ifp->if_mtu) ||
+           if_output_ml(ifp, &ml, sintosa(dst), rt))
                goto done;
-
-       while ((m0 = ml_dequeue(&fml)) != NULL) {
-               error = ifp->if_output(ifp, m0, sintosa(dst), rt);
-               if (error)
-                       break;
-       }
-       if (error)
-               ml_purge(&fml);
-       else
-               ipstat_inc(ips_fragmented);
+       ipstat_inc(ips_fragmented);
 
 done:
        if_put(ifp);
@@ -6695,16 +6685,20 @@ pf_route6(struct pf_pdesc *pd, struct pf_state *st)
         */
        if ((mtag = m_tag_find(m0, PACKET_TAG_PF_REASSEMBLED, NULL))) {
                (void) pf_refragment6(&m0, mtag, dst, ifp, rt);
-       } else if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu) {
+               goto done;
+       }
+
+       if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu) {
                ifp->if_output(ifp, m0, sin6tosa(dst), rt);
-       } else {
-               ip6stat_inc(ip6s_cantfrag);
-               if (st->rt != PF_DUPTO)
-                       pf_send_icmp(m0, ICMP6_PACKET_TOO_BIG, 0,
-                           ifp->if_mtu, pd->af, st->rule.ptr, pd->rdomain);
-               goto bad;
+               goto done;
        }
 
+       ip6stat_inc(ip6s_cantfrag);
+       if (st->rt != PF_DUPTO)
+               pf_send_icmp(m0, ICMP6_PACKET_TOO_BIG, 0,
+                   ifp->if_mtu, pd->af, st->rule.ptr, pd->rdomain);
+       goto bad;
+
 done:
        if_put(ifp);
        rtfree(rt);

diff --git a/sys/net/pf_norm.c b/sys/net/pf_norm.c
index db2f575..7ab4c00 100644 (file)
--- a/sys/net/pf_norm.c
+++ b/sys/net/pf_norm.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: pf_norm.c,v 1.226 2022/11/06 18:05:05 dlg Exp $ */
+/*     $OpenBSD: pf_norm.c,v 1.227 2023/05/07 16:23:23 bluhm Exp $ */
 
 /*
  * Copyright 2001 Niels Provos <provos@citi.umich.edu>
@@ -954,7 +954,7 @@ pf_refragment6(struct mbuf **m0, struct m_tag *mtag, struct sockaddr_in6 *dst,
     struct ifnet *ifp, struct rtentry *rt)
 {
        struct mbuf             *m = *m0;
-       struct mbuf_list         fml;
+       struct mbuf_list         ml;
        struct pf_fragment_tag  *ftag = (struct pf_fragment_tag *)(mtag + 1);
        u_int32_t                mtu;
        u_int16_t                hdrlen, extoff, maxlen;
@@ -997,14 +997,14 @@ pf_refragment6(struct mbuf **m0, struct m_tag *mtag, struct sockaddr_in6 *dst,
         * we drop the packet.
         */
        mtu = hdrlen + sizeof(struct ip6_frag) + maxlen;
-       error = ip6_fragment(m, &fml, hdrlen, proto, mtu);
+       error = ip6_fragment(m, &ml, hdrlen, proto, mtu);
        *m0 = NULL;     /* ip6_fragment() has consumed original packet. */
        if (error) {
                DPFPRINTF(LOG_NOTICE, "refragment error %d", error);
                return (PF_DROP);
        }
 
-       while ((m = ml_dequeue(&fml)) != NULL) {
+       while ((m = ml_dequeue(&ml)) != NULL) {
                m->m_pkthdr.pf.flags |= PF_TAG_REFRAGMENTED;
                if (ifp == NULL) {
                        ip6_forward(m, NULL, 0);

diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
index 4ecf82f..fbf8113 100644 (file)
--- a/sys/netinet/if_ether.c
+++ b/sys/netinet/if_ether.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_ether.c,v 1.263 2023/04/25 16:24:25 bluhm Exp $    */
+/*     $OpenBSD: if_ether.c,v 1.264 2023/05/07 16:23:23 bluhm Exp $    */
 /*     $NetBSD: if_ether.c,v 1.31 1996/05/11 12:59:58 mycroft Exp $    */
 
 /*
@@ -723,7 +723,7 @@ arpcache(struct ifnet *ifp, struct ether_arp *ea, struct rtentry *rt)
 
        la->la_asked = 0;
        la->la_refreshed = 0;
-       if_mqoutput(ifp, &la->la_mq, &la_hold_total, rt_key(rt), rt);
+       if_output_mq(ifp, &la->la_mq, &la_hold_total, rt_key(rt), rt);
 
        return (0);
 }

diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c
index b0c6ed7..c44ad8a 100644 (file)
--- a/sys/netinet/ip_output.c
+++ b/sys/netinet/ip_output.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: ip_output.c,v 1.382 2022/08/12 17:04:16 bluhm Exp $   */
+/*     $OpenBSD: ip_output.c,v 1.383 2023/05/07 16:23:23 bluhm Exp $   */
 /*     $NetBSD: ip_output.c,v 1.28 1996/02/13 23:43:07 christos Exp $  */
 
 /*
@@ -104,7 +104,7 @@ ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
 {
        struct ip *ip;
        struct ifnet *ifp = NULL;
-       struct mbuf_list fml;
+       struct mbuf_list ml;
        int hlen = sizeof (struct ip);
        int error = 0;
        struct route iproute;
@@ -505,19 +505,10 @@ sendit:
                goto bad;
        }
 
-       error = ip_fragment(m, &fml, ifp, mtu);
-       if (error)
+       if ((error = ip_fragment(m, &ml, ifp, mtu)) ||
+           (error = if_output_ml(ifp, &ml, sintosa(dst), ro->ro_rt)))
                goto done;
-
-       while ((m = ml_dequeue(&fml)) != NULL) {
-               error = ifp->if_output(ifp, m, sintosa(dst), ro->ro_rt);
-               if (error)
-                       break;
-       }
-       if (error)
-               ml_purge(&fml);
-       else
-               ipstat_inc(ips_fragmented);
+       ipstat_inc(ips_fragmented);
 
 done:
        if (ro == &iproute && ro->ro_rt)
@@ -677,16 +668,15 @@ ip_output_ipsec_send(struct tdb *tdb, struct mbuf *m, struct route *ro, int fwd)
 #endif /* IPSEC */
 
 int
-ip_fragment(struct mbuf *m0, struct mbuf_list *fml, struct ifnet *ifp,
+ip_fragment(struct mbuf *m0, struct mbuf_list *ml, struct ifnet *ifp,
     u_long mtu)
 {
-       struct mbuf *m;
        struct ip *ip;
        int firstlen, hlen, tlen, len, off;
        int error;
 
-       ml_init(fml);
-       ml_enqueue(fml, m0);
+       ml_init(ml);
+       ml_enqueue(ml, m0);
 
        ip = mtod(m0, struct ip *);
        hlen = ip->ip_hl << 2;
@@ -705,10 +695,11 @@ ip_fragment(struct mbuf *m0, struct mbuf_list *fml, struct ifnet *ifp,
        in_proto_cksum_out(m0, NULL);
 
        /*
-        * Loop through length of segment after first fragment,
+        * Loop through length of payload after first fragment,
         * make new header and copy data of each part and link onto chain.
         */
        for (off = hlen + firstlen; off < tlen; off += len) {
+               struct mbuf *m;
                struct ip *mhip;
                int mhlen;
 
@@ -717,8 +708,7 @@ ip_fragment(struct mbuf *m0, struct mbuf_list *fml, struct ifnet *ifp,
                        error = ENOBUFS;
                        goto bad;
                }
-               ml_enqueue(fml, m);
-
+               ml_enqueue(ml, m);
                if ((error = m_dup_pkthdr(m, m0, M_DONTWAIT)) != 0)
                        goto bad;
                m->m_data += max_linkhdr;
@@ -762,25 +752,26 @@ ip_fragment(struct mbuf *m0, struct mbuf_list *fml, struct ifnet *ifp,
         * Update first fragment by trimming what's been copied out
         * and updating header, then send each fragment (in order).
         */
-       m = m0;
-       m_adj(m, hlen + firstlen - tlen);
-       ip->ip_off |= htons(IP_MF);
-       ip->ip_len = htons(m->m_pkthdr.len);
+       if (hlen + firstlen < tlen) {
+               m_adj(m0, hlen + firstlen - tlen);
+               ip->ip_off |= htons(IP_MF);
+       }
+       ip->ip_len = htons(m0->m_pkthdr.len);
 
        ip->ip_sum = 0;
-       if (in_ifcap_cksum(m, ifp, IFCAP_CSUM_IPv4))
-               m->m_pkthdr.csum_flags |= M_IPV4_CSUM_OUT;
+       if (in_ifcap_cksum(m0, ifp, IFCAP_CSUM_IPv4))
+               m0->m_pkthdr.csum_flags |= M_IPV4_CSUM_OUT;
        else {
                ipstat_inc(ips_outswcsum);
-               ip->ip_sum = in_cksum(m, hlen);
+               ip->ip_sum = in_cksum(m0, hlen);
        }
 
-       ipstat_add(ips_ofragments, ml_len(fml));
+       ipstat_add(ips_ofragments, ml_len(ml));
        return (0);
 
 bad:
        ipstat_inc(ips_odropped);
-       ml_purge(fml);
+       ml_purge(ml);
        return (error);
 }
 

diff --git a/sys/netinet6/ip6_output.c b/sys/netinet6/ip6_output.c
index 07e13d5..6fe0f1c 100644 (file)
--- a/sys/netinet6/ip6_output.c
+++ b/sys/netinet6/ip6_output.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: ip6_output.c,v 1.272 2022/11/12 02:50:59 kn Exp $     */
+/*     $OpenBSD: ip6_output.c,v 1.273 2023/05/07 16:23:24 bluhm Exp $  */
 /*     $KAME: ip6_output.c,v 1.172 2001/03/25 09:55:56 itojun Exp $    */
 
 /*
@@ -165,7 +165,7 @@ ip6_output(struct mbuf *m, struct ip6_pktopts *opt, struct route_in6 *ro,
 {
        struct ip6_hdr *ip6;
        struct ifnet *ifp = NULL;
-       struct mbuf_list fml;
+       struct mbuf_list ml;
        int hlen, tlen;
        struct route_in6 ip6route;
        struct rtentry *rt = NULL;
@@ -751,19 +751,10 @@ reroute:
                ip6->ip6_nxt = IPPROTO_FRAGMENT;
        }
 
-       error = ip6_fragment(m, &fml, hlen, nextproto, mtu);
-       if (error)
+       if ((error = ip6_fragment(m, &ml, hlen, nextproto, mtu)) ||
+           (error = if_output_ml(ifp, &ml, sin6tosa(dst), ro->ro_rt)))
                goto done;
-
-       while ((m = ml_dequeue(&fml)) != NULL) {
-               error = ifp->if_output(ifp, m, sin6tosa(dst), ro->ro_rt);
-               if (error)
-                       break;
-       }
-       if (error)
-               ml_purge(&fml);
-       else
-               ip6stat_inc(ip6s_fragmented);
+       ip6stat_inc(ip6s_fragmented);
 
 done:
        if (ro == &ip6route && ro->ro_rt) {
@@ -789,16 +780,15 @@ bad:
 }
 
 int
-ip6_fragment(struct mbuf *m0, struct mbuf_list *fml, int hlen,
-    u_char nextproto, u_long mtu)
+ip6_fragment(struct mbuf *m0, struct mbuf_list *ml, int hlen, u_char nextproto,
+    u_long mtu)
 {
-       struct mbuf *m;
        struct ip6_hdr *ip6;
        u_int32_t id;
        int tlen, len, off;
        int error;
 
-       ml_init(fml);
+       ml_init(ml);
 
        ip6 = mtod(m0, struct ip6_hdr *);
        tlen = m0->m_pkthdr.len;
@@ -810,10 +800,11 @@ ip6_fragment(struct mbuf *m0, struct mbuf_list *fml, int hlen,
        id = htonl(ip6_randomid());
 
        /*
-        * Loop through length of segment,
+        * Loop through length of payload,
         * make new header and copy data of each part and link onto chain.
         */
        for (off = hlen; off < tlen; off += len) {
+               struct mbuf *m;
                struct mbuf *mlast;
                struct ip6_hdr *mhip6;
                struct ip6_frag *ip6f;
@@ -823,8 +814,7 @@ ip6_fragment(struct mbuf *m0, struct mbuf_list *fml, int hlen,
                        error = ENOBUFS;
                        goto bad;
                }
-               ml_enqueue(fml, m);
-
+               ml_enqueue(ml, m);
                if ((error = m_dup_pkthdr(m, m0, M_DONTWAIT)) != 0)
                        goto bad;
                m->m_data += max_linkhdr;
@@ -856,13 +846,13 @@ ip6_fragment(struct mbuf *m0, struct mbuf_list *fml, int hlen,
                ip6f->ip6f_nxt = nextproto;
        }
 
-       ip6stat_add(ip6s_ofragments, ml_len(fml));
+       ip6stat_add(ip6s_ofragments, ml_len(ml));
        m_freem(m0);
        return (0);
 
 bad:
        ip6stat_inc(ip6s_odropped);
-       ml_purge(fml);
+       ml_purge(ml);
        m_freem(m0);
        return (error);
 }

diff --git a/sys/netinet6/nd6.c b/sys/netinet6/nd6.c
index 47efb5c..5dc07a6 100644 (file)
--- a/sys/netinet6/nd6.c
+++ b/sys/netinet6/nd6.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: nd6.c,v 1.275 2023/05/04 06:56:56 bluhm Exp $ */
+/*     $OpenBSD: nd6.c,v 1.276 2023/05/07 16:23:24 bluhm Exp $ */
 /*     $KAME: nd6.c,v 1.280 2002/06/08 19:52:07 itojun Exp $   */
 
 /*
@@ -1181,7 +1181,7 @@ fail:
                         * meaningless.
                         */
                        nd6_llinfo_settimer(ln, nd6_gctimer);
-                       if_mqoutput(ifp, &ln->ln_mq, &ln_hold_total,
+                       if_output_mq(ifp, &ln->ln_mq, &ln_hold_total,
                            rt_key(rt), rt);
                } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) {
                        /* probe right away */

diff --git a/sys/netinet6/nd6_nbr.c b/sys/netinet6/nd6_nbr.c
index 583dc16..30b8ffe 100644 (file)
--- a/sys/netinet6/nd6_nbr.c
+++ b/sys/netinet6/nd6_nbr.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: nd6_nbr.c,v 1.148 2023/05/04 06:56:56 bluhm Exp $     */
+/*     $OpenBSD: nd6_nbr.c,v 1.149 2023/05/07 16:23:24 bluhm Exp $     */
 /*     $KAME: nd6_nbr.c,v 1.61 2001/02/10 16:06:14 jinmei Exp $        */
 
 /*
@@ -851,7 +851,7 @@ nd6_na_input(struct mbuf *m, int off, int icmp6len)
        }
        rt->rt_flags &= ~RTF_REJECT;
        ln->ln_asked = 0;
-       if_mqoutput(ifp, &ln->ln_mq, &ln_hold_total, rt_key(rt), rt);
+       if_output_mq(ifp, &ln->ln_mq, &ln_hold_total, rt_key(rt), rt);
 
  freeit:
        rtfree(rt);