The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/netinet/ip_fastfwd.c

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    1 /*-
    2  * Copyright (c) 2003 Andre Oppermann, Internet Business Solutions AG
    3  * All rights reserved.
    4  *
    5  * Redistribution and use in source and binary forms, with or without
    6  * modification, are permitted provided that the following conditions
    7  * are met:
    8  * 1. Redistributions of source code must retain the above copyright
    9  *    notice, this list of conditions and the following disclaimer.
   10  * 2. Redistributions in binary form must reproduce the above copyright
   11  *    notice, this list of conditions and the following disclaimer in the
   12  *    documentation and/or other materials provided with the distribution.
   13  * 3. The name of the author may not be used to endorse or promote
   14  *    products derived from this software without specific prior written
   15  *    permission.
   16  *
   17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   27  * SUCH DAMAGE.
   28  */
   29 
   30 /*
   31  * ip_fastforward gets its speed from processing the forwarded packet to
   32  * completion (if_output on the other side) without any queues or netisr's.
   33  * The receiving interface DMAs the packet into memory, the upper half of
   34  * driver calls ip_fastforward, we do our routing table lookup and directly
   35  * send it off to the outgoing interface, which DMAs the packet to the
   36  * network card. The only part of the packet we touch with the CPU is the
   37  * IP header (unless there are complex firewall rules touching other parts
   38  * of the packet, but that is up to you). We are essentially limited by bus
   39  * bandwidth and how fast the network card/driver can set up receives and
   40  * transmits.
   41  *
   42  * We handle basic errors, IP header errors, checksum errors,
   43  * destination unreachable, fragmentation and fragmentation needed and
   44  * report them via ICMP to the sender.
   45  *
   46  * Else if something is not pure IPv4 unicast forwarding we fall back to
   47  * the normal ip_input processing path. We should only be called from
   48  * interfaces connected to the outside world.
   49  *
   50  * Firewalling is fully supported including divert, ipfw fwd and ipfilter
   51  * ipnat and address rewrite.
   52  *
   53  * IPSEC is not supported if this host is a tunnel broker. IPSEC is
   54  * supported for connections to/from local host.
   55  *
   56  * We try to do the least expensive (in CPU ops) checks and operations
   57  * first to catch junk with as little overhead as possible.
   58  * 
   59  * We take full advantage of hardware support for IP checksum and
   60  * fragmentation offloading.
   61  *
   62  * We don't do ICMP redirect in the fast forwarding path. I have had my own
   63  * cases where two core routers with Zebra routing suite would send millions
   64  * ICMP redirects to connected hosts if the destination router was not the
   65  * default gateway. In one case it was filling the routing table of a host
   66  * with approximately 300.000 cloned redirect entries until it ran out of
   67  * kernel memory. However the networking code proved very robust and it didn't
   68  * crash or fail in other ways.
   69  */
   70 
   71 /*
   72  * Many thanks to Matt Thomas of NetBSD for basic structure of ip_flow.c which
   73  * is being followed here.
   74  */
   75 
   76 #include <sys/cdefs.h>
   77 __FBSDID("$FreeBSD: releng/8.2/sys/netinet/ip_fastfwd.c 216356 2010-12-10 14:06:50Z bz $");
   78 
   79 #include "opt_ipfw.h"
   80 #include "opt_ipstealth.h"
   81 
   82 #include <sys/param.h>
   83 #include <sys/systm.h>
   84 #include <sys/kernel.h>
   85 #include <sys/malloc.h>
   86 #include <sys/mbuf.h>
   87 #include <sys/protosw.h>
   88 #include <sys/socket.h>
   89 #include <sys/sysctl.h>
   90 
   91 #include <net/pfil.h>
   92 #include <net/if.h>
   93 #include <net/if_types.h>
   94 #include <net/if_var.h>
   95 #include <net/if_dl.h>
   96 #include <net/route.h>
   97 #include <net/vnet.h>
   98 
   99 #include <netinet/in.h>
  100 #include <netinet/in_systm.h>
  101 #include <netinet/in_var.h>
  102 #include <netinet/ip.h>
  103 #include <netinet/ip_var.h>
  104 #include <netinet/ip_icmp.h>
  105 #include <netinet/ip_options.h>
  106 
  107 #include <machine/in_cksum.h>
  108 
  109 static VNET_DEFINE(int, ipfastforward_active);
  110 #define V_ipfastforward_active          VNET(ipfastforward_active)
  111 
  112 SYSCTL_VNET_INT(_net_inet_ip, OID_AUTO, fastforwarding, CTLFLAG_RW,
  113     &VNET_NAME(ipfastforward_active), 0, "Enable fast IP forwarding");
  114 
  115 static struct sockaddr_in *
  116 ip_findroute(struct route *ro, struct in_addr dest, struct mbuf *m)
  117 {
  118         struct sockaddr_in *dst;
  119         struct rtentry *rt;
  120 
  121         /*
  122          * Find route to destination.
  123          */
  124         bzero(ro, sizeof(*ro));
  125         dst = (struct sockaddr_in *)&ro->ro_dst;
  126         dst->sin_family = AF_INET;
  127         dst->sin_len = sizeof(*dst);
  128         dst->sin_addr.s_addr = dest.s_addr;
  129         in_rtalloc_ign(ro, 0, M_GETFIB(m));
  130 
  131         /*
  132          * Route there and interface still up?
  133          */
  134         rt = ro->ro_rt;
  135         if (rt && (rt->rt_flags & RTF_UP) &&
  136             (rt->rt_ifp->if_flags & IFF_UP) &&
  137             (rt->rt_ifp->if_drv_flags & IFF_DRV_RUNNING)) {
  138                 if (rt->rt_flags & RTF_GATEWAY)
  139                         dst = (struct sockaddr_in *)rt->rt_gateway;
  140         } else {
  141                 IPSTAT_INC(ips_noroute);
  142                 IPSTAT_INC(ips_cantforward);
  143                 if (rt)
  144                         RTFREE(rt);
  145                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
  146                 return NULL;
  147         }
  148         return dst;
  149 }
  150 
  151 /*
  152  * Try to forward a packet based on the destination address.
  153  * This is a fast path optimized for the plain forwarding case.
  154  * If the packet is handled (and consumed) here then we return 1;
  155  * otherwise 0 is returned and the packet should be delivered
  156  * to ip_input for full processing.
  157  */
  158 struct mbuf *
  159 ip_fastforward(struct mbuf *m)
  160 {
  161         struct ip *ip;
  162         struct mbuf *m0 = NULL;
  163         struct route ro;
  164         struct sockaddr_in *dst = NULL;
  165         struct ifnet *ifp;
  166         struct in_addr odest, dest;
  167         u_short sum, ip_len;
  168         int error = 0;
  169         int hlen, mtu;
  170 #ifdef IPFIREWALL_FORWARD
  171         struct m_tag *fwd_tag;
  172 #endif
  173 
  174         /*
  175          * Are we active and forwarding packets?
  176          */
  177         if (!V_ipfastforward_active || !V_ipforwarding)
  178                 return m;
  179 
  180         M_ASSERTVALID(m);
  181         M_ASSERTPKTHDR(m);
  182 
  183         bzero(&ro, sizeof(ro));
  184 
  185         /*
  186          * Step 1: check for packet drop conditions (and sanity checks)
  187          */
  188 
  189         /*
  190          * Is entire packet big enough?
  191          */
  192         if (m->m_pkthdr.len < sizeof(struct ip)) {
  193                 IPSTAT_INC(ips_tooshort);
  194                 goto drop;
  195         }
  196 
  197         /*
  198          * Is first mbuf large enough for ip header and is header present?
  199          */
  200         if (m->m_len < sizeof (struct ip) &&
  201            (m = m_pullup(m, sizeof (struct ip))) == NULL) {
  202                 IPSTAT_INC(ips_toosmall);
  203                 return NULL;    /* mbuf already free'd */
  204         }
  205 
  206         ip = mtod(m, struct ip *);
  207 
  208         /*
  209          * Is it IPv4?
  210          */
  211         if (ip->ip_v != IPVERSION) {
  212                 IPSTAT_INC(ips_badvers);
  213                 goto drop;
  214         }
  215 
  216         /*
  217          * Is IP header length correct and is it in first mbuf?
  218          */
  219         hlen = ip->ip_hl << 2;
  220         if (hlen < sizeof(struct ip)) { /* minimum header length */
  221                 IPSTAT_INC(ips_badhlen);
  222                 goto drop;
  223         }
  224         if (hlen > m->m_len) {
  225                 if ((m = m_pullup(m, hlen)) == NULL) {
  226                         IPSTAT_INC(ips_badhlen);
  227                         return NULL;    /* mbuf already free'd */
  228                 }
  229                 ip = mtod(m, struct ip *);
  230         }
  231 
  232         /*
  233          * Checksum correct?
  234          */
  235         if (m->m_pkthdr.csum_flags & CSUM_IP_CHECKED)
  236                 sum = !(m->m_pkthdr.csum_flags & CSUM_IP_VALID);
  237         else {
  238                 if (hlen == sizeof(struct ip))
  239                         sum = in_cksum_hdr(ip);
  240                 else
  241                         sum = in_cksum(m, hlen);
  242         }
  243         if (sum) {
  244                 IPSTAT_INC(ips_badsum);
  245                 goto drop;
  246         }
  247 
  248         /*
  249          * Remember that we have checked the IP header and found it valid.
  250          */
  251         m->m_pkthdr.csum_flags |= (CSUM_IP_CHECKED | CSUM_IP_VALID);
  252 
  253         ip_len = ntohs(ip->ip_len);
  254 
  255         /*
  256          * Is IP length longer than packet we have got?
  257          */
  258         if (m->m_pkthdr.len < ip_len) {
  259                 IPSTAT_INC(ips_tooshort);
  260                 goto drop;
  261         }
  262 
  263         /*
  264          * Is packet longer than IP header tells us? If yes, truncate packet.
  265          */
  266         if (m->m_pkthdr.len > ip_len) {
  267                 if (m->m_len == m->m_pkthdr.len) {
  268                         m->m_len = ip_len;
  269                         m->m_pkthdr.len = ip_len;
  270                 } else
  271                         m_adj(m, ip_len - m->m_pkthdr.len);
  272         }
  273 
  274         /*
  275          * Is packet from or to 127/8?
  276          */
  277         if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
  278             (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
  279                 IPSTAT_INC(ips_badaddr);
  280                 goto drop;
  281         }
  282 
  283 #ifdef ALTQ
  284         /*
  285          * Is packet dropped by traffic conditioner?
  286          */
  287         if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0)
  288                 goto drop;
  289 #endif
  290 
  291         /*
  292          * Step 2: fallback conditions to normal ip_input path processing
  293          */
  294 
  295         /*
  296          * Only IP packets without options
  297          */
  298         if (ip->ip_hl != (sizeof(struct ip) >> 2)) {
  299                 if (ip_doopts == 1)
  300                         return m;
  301                 else if (ip_doopts == 2) {
  302                         icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_FILTER_PROHIB,
  303                                 0, 0);
  304                         return NULL;    /* mbuf already free'd */
  305                 }
  306                 /* else ignore IP options and continue */
  307         }
  308 
  309         /*
  310          * Only unicast IP, not from loopback, no L2 or IP broadcast,
  311          * no multicast, no INADDR_ANY
  312          *
  313          * XXX: Probably some of these checks could be direct drop
  314          * conditions.  However it is not clear whether there are some
  315          * hacks or obscure behaviours which make it neccessary to
  316          * let ip_input handle it.  We play safe here and let ip_input
  317          * deal with it until it is proven that we can directly drop it.
  318          */
  319         if ((m->m_flags & (M_BCAST|M_MCAST)) ||
  320             (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) ||
  321             ntohl(ip->ip_src.s_addr) == (u_long)INADDR_BROADCAST ||
  322             ntohl(ip->ip_dst.s_addr) == (u_long)INADDR_BROADCAST ||
  323             IN_MULTICAST(ntohl(ip->ip_src.s_addr)) ||
  324             IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
  325             IN_LINKLOCAL(ntohl(ip->ip_src.s_addr)) ||
  326             IN_LINKLOCAL(ntohl(ip->ip_dst.s_addr)) ||
  327             ip->ip_src.s_addr == INADDR_ANY ||
  328             ip->ip_dst.s_addr == INADDR_ANY )
  329                 return m;
  330 
  331         /*
  332          * Is it for a local address on this host?
  333          */
  334         if (in_localip(ip->ip_dst))
  335                 return m;
  336 
  337         IPSTAT_INC(ips_total);
  338 
  339         /*
  340          * Step 3: incoming packet firewall processing
  341          */
  342 
  343         /*
  344          * Convert to host representation
  345          */
  346         ip->ip_len = ntohs(ip->ip_len);
  347         ip->ip_off = ntohs(ip->ip_off);
  348 
  349         odest.s_addr = dest.s_addr = ip->ip_dst.s_addr;
  350 
  351         /*
  352          * Run through list of ipfilter hooks for input packets
  353          */
  354         if (!PFIL_HOOKED(&V_inet_pfil_hook))
  355                 goto passin;
  356 
  357         if (pfil_run_hooks(
  358             &V_inet_pfil_hook, &m, m->m_pkthdr.rcvif, PFIL_IN, NULL) ||
  359             m == NULL)
  360                 goto drop;
  361 
  362         M_ASSERTVALID(m);
  363         M_ASSERTPKTHDR(m);
  364 
  365         ip = mtod(m, struct ip *);      /* m may have changed by pfil hook */
  366         dest.s_addr = ip->ip_dst.s_addr;
  367 
  368         /*
  369          * Destination address changed?
  370          */
  371         if (odest.s_addr != dest.s_addr) {
  372                 /*
  373                  * Is it now for a local address on this host?
  374                  */
  375                 if (in_localip(dest))
  376                         goto forwardlocal;
  377                 /*
  378                  * Go on with new destination address
  379                  */
  380         }
  381 #ifdef IPFIREWALL_FORWARD
  382         if (m->m_flags & M_FASTFWD_OURS) {
  383                 /*
  384                  * ipfw changed it for a local address on this host.
  385                  */
  386                 goto forwardlocal;
  387         }
  388 #endif /* IPFIREWALL_FORWARD */
  389 
  390 passin:
  391         /*
  392          * Step 4: decrement TTL and look up route
  393          */
  394 
  395         /*
  396          * Check TTL
  397          */
  398 #ifdef IPSTEALTH
  399         if (!V_ipstealth) {
  400 #endif
  401         if (ip->ip_ttl <= IPTTLDEC) {
  402                 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, 0, 0);
  403                 return NULL;    /* mbuf already free'd */
  404         }
  405 
  406         /*
  407          * Decrement the TTL and incrementally change the IP header checksum.
  408          * Don't bother doing this with hw checksum offloading, it's faster
  409          * doing it right here.
  410          */
  411         ip->ip_ttl -= IPTTLDEC;
  412         if (ip->ip_sum >= (u_int16_t) ~htons(IPTTLDEC << 8))
  413                 ip->ip_sum -= ~htons(IPTTLDEC << 8);
  414         else
  415                 ip->ip_sum += htons(IPTTLDEC << 8);
  416 #ifdef IPSTEALTH
  417         }
  418 #endif
  419 
  420         /*
  421          * Find route to destination.
  422          */
  423         if ((dst = ip_findroute(&ro, dest, m)) == NULL)
  424                 return NULL;    /* icmp unreach already sent */
  425         ifp = ro.ro_rt->rt_ifp;
  426 
  427         /*
  428          * Immediately drop blackholed traffic, and directed broadcasts
  429          * for either the all-ones or all-zero subnet addresses on
  430          * locally attached networks.
  431          */
  432         if ((ro.ro_rt->rt_flags & (RTF_BLACKHOLE|RTF_BROADCAST)) != 0)
  433                 goto drop;
  434 
  435         /*
  436          * Step 5: outgoing firewall packet processing
  437          */
  438 
  439         /*
  440          * Run through list of hooks for output packets.
  441          */
  442         if (!PFIL_HOOKED(&V_inet_pfil_hook))
  443                 goto passout;
  444 
  445         if (pfil_run_hooks(&V_inet_pfil_hook, &m, ifp, PFIL_OUT, NULL) || m == NULL) {
  446                 goto drop;
  447         }
  448 
  449         M_ASSERTVALID(m);
  450         M_ASSERTPKTHDR(m);
  451 
  452         ip = mtod(m, struct ip *);
  453         dest.s_addr = ip->ip_dst.s_addr;
  454 
  455         /*
  456          * Destination address changed?
  457          */
  458 #ifndef IPFIREWALL_FORWARD
  459         if (odest.s_addr != dest.s_addr) {
  460 #else
  461         fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
  462         if (odest.s_addr != dest.s_addr || fwd_tag != NULL) {
  463 #endif /* IPFIREWALL_FORWARD */
  464                 /*
  465                  * Is it now for a local address on this host?
  466                  */
  467 #ifndef IPFIREWALL_FORWARD
  468                 if (in_localip(dest)) {
  469 #else
  470                 if (m->m_flags & M_FASTFWD_OURS || in_localip(dest)) {
  471 #endif /* IPFIREWALL_FORWARD */
  472 forwardlocal:
  473                         /*
  474                          * Return packet for processing by ip_input().
  475                          * Keep host byte order as expected at ip_input's
  476                          * "ours"-label.
  477                          */
  478                         m->m_flags |= M_FASTFWD_OURS;
  479                         if (ro.ro_rt)
  480                                 RTFREE(ro.ro_rt);
  481                         return m;
  482                 }
  483                 /*
  484                  * Redo route lookup with new destination address
  485                  */
  486 #ifdef IPFIREWALL_FORWARD
  487                 if (fwd_tag) {
  488                         dest.s_addr = ((struct sockaddr_in *)
  489                                     (fwd_tag + 1))->sin_addr.s_addr;
  490                         m_tag_delete(m, fwd_tag);
  491                 }
  492 #endif /* IPFIREWALL_FORWARD */
  493                 RTFREE(ro.ro_rt);
  494                 if ((dst = ip_findroute(&ro, dest, m)) == NULL)
  495                         return NULL;    /* icmp unreach already sent */
  496                 ifp = ro.ro_rt->rt_ifp;
  497         }
  498 
  499 passout:
  500         /*
  501          * Step 6: send off the packet
  502          */
  503 
  504         /*
  505          * Check if route is dampned (when ARP is unable to resolve)
  506          */
  507         if ((ro.ro_rt->rt_flags & RTF_REJECT) &&
  508             (ro.ro_rt->rt_rmx.rmx_expire == 0 ||
  509             time_uptime < ro.ro_rt->rt_rmx.rmx_expire)) {
  510                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
  511                 goto consumed;
  512         }
  513 
  514 #ifndef ALTQ
  515         /*
  516          * Check if there is enough space in the interface queue
  517          */
  518         if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >=
  519             ifp->if_snd.ifq_maxlen) {
  520                 IPSTAT_INC(ips_odropped);
  521                 /* would send source quench here but that is depreciated */
  522                 goto drop;
  523         }
  524 #endif
  525 
  526         /*
  527          * Check if media link state of interface is not down
  528          */
  529         if (ifp->if_link_state == LINK_STATE_DOWN) {
  530                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
  531                 goto consumed;
  532         }
  533 
  534         /*
  535          * Check if packet fits MTU or if hardware will fragment for us
  536          */
  537         if (ro.ro_rt->rt_rmx.rmx_mtu)
  538                 mtu = min(ro.ro_rt->rt_rmx.rmx_mtu, ifp->if_mtu);
  539         else
  540                 mtu = ifp->if_mtu;
  541 
  542         if (ip->ip_len <= mtu ||
  543             (ifp->if_hwassist & CSUM_FRAGMENT && (ip->ip_off & IP_DF) == 0)) {
  544                 /*
  545                  * Restore packet header fields to original values
  546                  */
  547                 ip->ip_len = htons(ip->ip_len);
  548                 ip->ip_off = htons(ip->ip_off);
  549                 /*
  550                  * Send off the packet via outgoing interface
  551                  */
  552                 error = (*ifp->if_output)(ifp, m,
  553                                 (struct sockaddr *)dst, &ro);
  554         } else {
  555                 /*
  556                  * Handle EMSGSIZE with icmp reply needfrag for TCP MTU discovery
  557                  */
  558                 if (ip->ip_off & IP_DF) {
  559                         IPSTAT_INC(ips_cantfrag);
  560                         icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG,
  561                                 0, mtu);
  562                         goto consumed;
  563                 } else {
  564                         /*
  565                          * We have to fragment the packet
  566                          */
  567                         m->m_pkthdr.csum_flags |= CSUM_IP;
  568                         /*
  569                          * ip_fragment expects ip_len and ip_off in host byte
  570                          * order but returns all packets in network byte order
  571                          */
  572                         if (ip_fragment(ip, &m, mtu, ifp->if_hwassist,
  573                                         (~ifp->if_hwassist & CSUM_DELAY_IP))) {
  574                                 goto drop;
  575                         }
  576                         KASSERT(m != NULL, ("null mbuf and no error"));
  577                         /*
  578                          * Send off the fragments via outgoing interface
  579                          */
  580                         error = 0;
  581                         do {
  582                                 m0 = m->m_nextpkt;
  583                                 m->m_nextpkt = NULL;
  584 
  585                                 error = (*ifp->if_output)(ifp, m,
  586                                         (struct sockaddr *)dst, &ro);
  587                                 if (error)
  588                                         break;
  589                         } while ((m = m0) != NULL);
  590                         if (error) {
  591                                 /* Reclaim remaining fragments */
  592                                 for (m = m0; m; m = m0) {
  593                                         m0 = m->m_nextpkt;
  594                                         m_freem(m);
  595                                 }
  596                         } else
  597                                 IPSTAT_INC(ips_fragmented);
  598                 }
  599         }
  600 
  601         if (error != 0)
  602                 IPSTAT_INC(ips_odropped);
  603         else {
  604                 ro.ro_rt->rt_rmx.rmx_pksent++;
  605                 IPSTAT_INC(ips_forward);
  606                 IPSTAT_INC(ips_fastforward);
  607         }
  608 consumed:
  609         RTFREE(ro.ro_rt);
  610         return NULL;
  611 drop:
  612         if (m)
  613                 m_freem(m);
  614         if (ro.ro_rt)
  615                 RTFREE(ro.ro_rt);
  616         return NULL;
  617 }

Cache object: f9de0646c027f0d178eac13a8c4473cd


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