[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/netinet6/ip6_input.c

Version: -  FREEBSD  -  FREEBSD10  -  FREEBSD9  -  FREEBSD92  -  FREEBSD91  -  FREEBSD90  -  FREEBSD8  -  FREEBSD82  -  FREEBSD81  -  FREEBSD80  -  FREEBSD7  -  FREEBSD74  -  FREEBSD73  -  FREEBSD72  -  FREEBSD71  -  FREEBSD70  -  FREEBSD6  -  FREEBSD64  -  FREEBSD63  -  FREEBSD62  -  FREEBSD61  -  FREEBSD60  -  FREEBSD5  -  FREEBSD55  -  FREEBSD54  -  FREEBSD53  -  FREEBSD52  -  FREEBSD51  -  FREEBSD50  -  FREEBSD4  -  FREEBSD3  -  FREEBSD22  -  cheribsd  -  linux-2.6  -  linux-2.4.22  -  MK83  -  MK84  -  PLAN9  -  DFBSD  -  NETBSD  -  NETBSD5  -  NETBSD4  -  NETBSD3  -  NETBSD20  -  OPENBSD  -  xnu-517  -  xnu-792  -  xnu-792.6.70  -  xnu-1228  -  xnu-1456.1.26  -  xnu-1699.24.8  -  xnu-2050.18.24  -  OPENSOLARIS  -  minix-3-1-1  -  FREEBSD-LIBC  -  FREEBSD8-LIBC  -  FREEBSD7-LIBC  -  FREEBSD6-LIBC  -  GLIBC27 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
    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. Neither the name of the project nor the names of its contributors
   14  *    may be used to endorse or promote products derived from this software
   15  *    without specific prior written permission.
   16  *
   17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT 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 PROJECT 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  *      $KAME: ip6_input.c,v 1.259 2002/01/21 04:58:09 jinmei Exp $
   30  */
   31 
   32 /*-
   33  * Copyright (c) 1982, 1986, 1988, 1993
   34  *      The Regents of the University of California.  All rights reserved.
   35  *
   36  * Redistribution and use in source and binary forms, with or without
   37  * modification, are permitted provided that the following conditions
   38  * are met:
   39  * 1. Redistributions of source code must retain the above copyright
   40  *    notice, this list of conditions and the following disclaimer.
   41  * 2. Redistributions in binary form must reproduce the above copyright
   42  *    notice, this list of conditions and the following disclaimer in the
   43  *    documentation and/or other materials provided with the distribution.
   44  * 4. Neither the name of the University nor the names of its contributors
   45  *    may be used to endorse or promote products derived from this software
   46  *    without specific prior written permission.
   47  *
   48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   58  * SUCH DAMAGE.
   59  *
   60  *      @(#)ip_input.c  8.2 (Berkeley) 1/4/94
   61  */
   62 
   63 #include <sys/cdefs.h>
   64 __FBSDID("$FreeBSD: releng/8.0/sys/netinet6/ip6_input.c 196671 2009-08-30 22:36:46Z qingli $");
   65 
   66 #include "opt_inet.h"
   67 #include "opt_inet6.h"
   68 #include "opt_ipsec.h"
   69 
   70 #include <sys/param.h>
   71 #include <sys/systm.h>
   72 #include <sys/malloc.h>
   73 #include <sys/mbuf.h>
   74 #include <sys/proc.h>
   75 #include <sys/domain.h>
   76 #include <sys/protosw.h>
   77 #include <sys/socket.h>
   78 #include <sys/socketvar.h>
   79 #include <sys/errno.h>
   80 #include <sys/time.h>
   81 #include <sys/kernel.h>
   82 #include <sys/syslog.h>
   83 
   84 #include <net/if.h>
   85 #include <net/if_types.h>
   86 #include <net/if_dl.h>
   87 #include <net/route.h>
   88 #include <net/netisr.h>
   89 #include <net/pfil.h>
   90 #include <net/vnet.h>
   91 
   92 #include <netinet/in.h>
   93 #include <netinet/in_systm.h>
   94 #include <net/if_llatbl.h>
   95 #ifdef INET
   96 #include <netinet/ip.h>
   97 #include <netinet/ip_icmp.h>
   98 #endif /* INET */
   99 #include <netinet/ip6.h>
  100 #include <netinet6/in6_var.h>
  101 #include <netinet6/ip6_var.h>
  102 #include <netinet/in_pcb.h>
  103 #include <netinet/icmp6.h>
  104 #include <netinet6/scope6_var.h>
  105 #include <netinet6/in6_ifattach.h>
  106 #include <netinet6/nd6.h>
  107 
  108 #ifdef IPSEC
  109 #include <netipsec/ipsec.h>
  110 #include <netinet6/ip6_ipsec.h>
  111 #include <netipsec/ipsec6.h>
  112 #endif /* IPSEC */
  113 
  114 #include <netinet6/ip6protosw.h>
  115 
  116 extern struct domain inet6domain;
  117 
  118 u_char ip6_protox[IPPROTO_MAX];
  119 
  120 static struct netisr_handler ip6_nh = {
  121         .nh_name = "ip6",
  122         .nh_handler = ip6_input,
  123         .nh_proto = NETISR_IPV6,
  124         .nh_policy = NETISR_POLICY_FLOW,
  125 };
  126 
  127 VNET_DEFINE(struct in6_ifaddrhead, in6_ifaddrhead);
  128 VNET_DEFINE(struct ip6stat, ip6stat);
  129 
  130 VNET_DECLARE(struct callout, in6_tmpaddrtimer_ch);
  131 VNET_DECLARE(int, dad_init);
  132 VNET_DECLARE(int, pmtu_expire);
  133 VNET_DECLARE(int, pmtu_probe);
  134 VNET_DECLARE(u_long, rip6_sendspace);
  135 VNET_DECLARE(u_long, rip6_recvspace);
  136 VNET_DECLARE(int, icmp6errppslim);
  137 VNET_DECLARE(int, icmp6_nodeinfo);
  138 VNET_DECLARE(int, udp6_sendspace);
  139 VNET_DECLARE(int, udp6_recvspace);
  140 
  141 #define V_in6_tmpaddrtimer_ch           VNET(in6_tmpaddrtimer_ch)
  142 #define V_dad_init                      VNET(dad_init)
  143 #define V_pmtu_expire                   VNET(pmtu_expire)
  144 #define V_pmtu_probe                    VNET(pmtu_probe)
  145 #define V_rip6_sendspace                VNET(rip6_sendspace)
  146 #define V_rip6_recvspace                VNET(rip6_recvspace)
  147 #define V_icmp6errppslim                VNET(icmp6errppslim)
  148 #define V_icmp6_nodeinfo                VNET(icmp6_nodeinfo)
  149 #define V_udp6_sendspace                VNET(udp6_sendspace)
  150 #define V_udp6_recvspace                VNET(udp6_recvspace)
  151 
  152 struct rwlock in6_ifaddr_lock;
  153 RW_SYSINIT(in6_ifaddr_lock, &in6_ifaddr_lock, "in6_ifaddr_lock");
  154 
  155 struct pfil_head inet6_pfil_hook;
  156 
  157 static void ip6_init2(void *);
  158 static struct ip6aux *ip6_setdstifaddr(struct mbuf *, struct in6_ifaddr *);
  159 static int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *);
  160 #ifdef PULLDOWN_TEST
  161 static struct mbuf *ip6_pullexthdr(struct mbuf *, size_t, int);
  162 #endif
  163 
  164 /*
  165  * IP6 initialization: fill in IP6 protocol switch table.
  166  * All protocols not implemented in kernel go to raw IP6 protocol handler.
  167  */
  168 void
  169 ip6_init(void)
  170 {
  171         struct ip6protosw *pr;
  172         int i;
  173 
  174         V_in6_maxmtu = 0;
  175 #ifdef IP6_AUTO_LINKLOCAL
  176         V_ip6_auto_linklocal = IP6_AUTO_LINKLOCAL;
  177 #else
  178         V_ip6_auto_linklocal = 1;       /* enable by default */
  179 #endif
  180         TUNABLE_INT_FETCH("net.inet6.ip6.auto_linklocal",
  181             &V_ip6_auto_linklocal);
  182 
  183 #ifndef IPV6FORWARDING
  184 #ifdef GATEWAY6
  185 #define IPV6FORWARDING  1       /* forward IP6 packets not for us */
  186 #else
  187 #define IPV6FORWARDING  0       /* don't forward IP6 packets not for us */
  188 #endif /* GATEWAY6 */
  189 #endif /* !IPV6FORWARDING */
  190 
  191 #ifndef IPV6_SENDREDIRECTS
  192 #define IPV6_SENDREDIRECTS      1
  193 #endif
  194 
  195         V_ip6_forwarding = IPV6FORWARDING; /* act as router? */
  196         V_ip6_sendredirects = IPV6_SENDREDIRECTS;
  197         V_ip6_defhlim = IPV6_DEFHLIM;
  198         V_ip6_defmcasthlim = IPV6_DEFAULT_MULTICAST_HOPS;
  199         V_ip6_accept_rtadv = 0;  /* "IPV6FORWARDING ? 0 : 1" is dangerous */
  200         V_ip6_log_interval = 5;
  201         V_ip6_hdrnestlimit = 15; /* How many header options will we process? */
  202         V_ip6_dad_count = 1;     /* DupAddrDetectionTransmits */
  203         V_ip6_auto_flowlabel = 1;
  204         V_ip6_use_deprecated = 1;/* allow deprecated addr (RFC2462 5.5.4) */
  205         V_ip6_rr_prune = 5;      /* router renumbering prefix
  206                                   * walk list every 5 sec. */
  207         V_ip6_mcast_pmtu = 0;    /* enable pMTU discovery for multicast? */
  208         V_ip6_v6only = 1;
  209         V_ip6_keepfaith = 0;
  210         V_ip6_log_time = (time_t)0L;
  211 #ifdef IPSTEALTH
  212         V_ip6stealth = 0;
  213 #endif
  214         V_nd6_onlink_ns_rfc4861 = 0; /* allow 'on-link' nd6 NS (RFC 4861) */
  215 
  216         V_pmtu_expire = 60*10;
  217         V_pmtu_probe = 60*2;
  218 
  219         /* raw IP6 parameters */
  220         /*
  221          * Nominal space allocated to a raw ip socket.
  222          */
  223 #define RIPV6SNDQ       8192
  224 #define RIPV6RCVQ       8192
  225         V_rip6_sendspace = RIPV6SNDQ;
  226         V_rip6_recvspace = RIPV6RCVQ;
  227 
  228         /* ICMPV6 parameters */
  229         V_icmp6_rediraccept = 1;        /* accept and process redirects */
  230         V_icmp6_redirtimeout = 10 * 60; /* 10 minutes */
  231         V_icmp6errppslim = 100;         /* 100pps */
  232         /* control how to respond to NI queries */
  233         V_icmp6_nodeinfo = (ICMP6_NODEINFO_FQDNOK|ICMP6_NODEINFO_NODEADDROK);
  234 
  235         /* UDP on IP6 parameters */
  236         V_udp6_sendspace = 9216;        /* really max datagram size */
  237         V_udp6_recvspace = 40 * (1024 + sizeof(struct sockaddr_in6));
  238                                         /* 40 1K datagrams */
  239         V_dad_init = 0;
  240 
  241         TAILQ_INIT(&V_in6_ifaddrhead);
  242 
  243         scope6_init();
  244         addrsel_policy_init();
  245         nd6_init();
  246         frag6_init();
  247 
  248         V_ip6_desync_factor = arc4random() % MAX_TEMP_DESYNC_FACTOR;
  249 
  250         /* Skip global initialization stuff for non-default instances. */
  251         if (!IS_DEFAULT_VNET(curvnet))
  252                 return;
  253 
  254 #ifdef DIAGNOSTIC
  255         if (sizeof(struct protosw) != sizeof(struct ip6protosw))
  256                 panic("sizeof(protosw) != sizeof(ip6protosw)");
  257 #endif
  258         pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
  259         if (pr == NULL)
  260                 panic("ip6_init");
  261 
  262         /* Initialize the entire ip6_protox[] array to IPPROTO_RAW. */
  263         for (i = 0; i < IPPROTO_MAX; i++)
  264                 ip6_protox[i] = pr - inet6sw;
  265         /*
  266          * Cycle through IP protocols and put them into the appropriate place
  267          * in ip6_protox[].
  268          */
  269         for (pr = (struct ip6protosw *)inet6domain.dom_protosw;
  270             pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++)
  271                 if (pr->pr_domain->dom_family == PF_INET6 &&
  272                     pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) {
  273                         /* Be careful to only index valid IP protocols. */
  274                         if (pr->pr_protocol < IPPROTO_MAX)
  275                                 ip6_protox[pr->pr_protocol] = pr - inet6sw;
  276                 }
  277 
  278         /* Initialize packet filter hooks. */
  279         inet6_pfil_hook.ph_type = PFIL_TYPE_AF;
  280         inet6_pfil_hook.ph_af = AF_INET6;
  281         if ((i = pfil_head_register(&inet6_pfil_hook)) != 0)
  282                 printf("%s: WARNING: unable to register pfil hook, "
  283                         "error %d\n", __func__, i);
  284 
  285         netisr_register(&ip6_nh);
  286 }
  287 
  288 #ifdef VIMAGE
  289 void
  290 ip6_destroy()
  291 {
  292 
  293         nd6_destroy();
  294         callout_drain(&V_in6_tmpaddrtimer_ch);
  295 }
  296 #endif
  297 
  298 static int
  299 ip6_init2_vnet(const void *unused __unused)
  300 {
  301 
  302         /* nd6_timer_init */
  303         callout_init(&V_nd6_timer_ch, 0);
  304         callout_reset(&V_nd6_timer_ch, hz, nd6_timer, curvnet);
  305 
  306         /* timer for regeneranation of temporary addresses randomize ID */
  307         callout_init(&V_in6_tmpaddrtimer_ch, 0);
  308         callout_reset(&V_in6_tmpaddrtimer_ch,
  309                       (V_ip6_temp_preferred_lifetime - V_ip6_desync_factor -
  310                        V_ip6_temp_regen_advance) * hz,
  311                       in6_tmpaddrtimer, curvnet);
  312 
  313         return (0);
  314 }
  315 
  316 static void
  317 ip6_init2(void *dummy)
  318 {
  319 
  320         ip6_init2_vnet(NULL);
  321 }
  322 
  323 /* cheat */
  324 /* This must be after route_init(), which is now SI_ORDER_THIRD */
  325 SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ip6_init2, NULL);
  326 
  327 void
  328 ip6_input(struct mbuf *m)
  329 {
  330         struct ip6_hdr *ip6;
  331         int off = sizeof(struct ip6_hdr), nest;
  332         u_int32_t plen;
  333         u_int32_t rtalert = ~0;
  334         int nxt, ours = 0;
  335         struct ifnet *deliverifp = NULL, *ifp = NULL;
  336         struct in6_addr odst;
  337         struct route_in6 rin6;
  338         int srcrt = 0;
  339         struct llentry *lle = NULL;
  340         struct sockaddr_in6 dst6, *dst;
  341 
  342         bzero(&rin6, sizeof(struct route_in6));
  343 #ifdef IPSEC
  344         /*
  345          * should the inner packet be considered authentic?
  346          * see comment in ah4_input().
  347          * NB: m cannot be NULL when passed to the input routine
  348          */
  349 
  350         m->m_flags &= ~M_AUTHIPHDR;
  351         m->m_flags &= ~M_AUTHIPDGM;
  352 
  353 #endif /* IPSEC */
  354 
  355         /*
  356          * make sure we don't have onion peering information into m_tag.
  357          */
  358         ip6_delaux(m);
  359 
  360         /*
  361          * mbuf statistics
  362          */
  363         if (m->m_flags & M_EXT) {
  364                 if (m->m_next)
  365                         V_ip6stat.ip6s_mext2m++;
  366                 else
  367                         V_ip6stat.ip6s_mext1++;
  368         } else {
  369 #define M2MMAX  (sizeof(V_ip6stat.ip6s_m2m)/sizeof(V_ip6stat.ip6s_m2m[0]))
  370                 if (m->m_next) {
  371                         if (m->m_flags & M_LOOP) {
  372                                 V_ip6stat.ip6s_m2m[V_loif->if_index]++;
  373                         } else if (m->m_pkthdr.rcvif->if_index < M2MMAX)
  374                                 V_ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++;
  375                         else
  376                                 V_ip6stat.ip6s_m2m[0]++;
  377                 } else
  378                         V_ip6stat.ip6s_m1++;
  379 #undef M2MMAX
  380         }
  381 
  382         /* drop the packet if IPv6 operation is disabled on the IF */
  383         if ((ND_IFINFO(m->m_pkthdr.rcvif)->flags & ND6_IFF_IFDISABLED)) {
  384                 m_freem(m);
  385                 return;
  386         }
  387 
  388         in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive);
  389         V_ip6stat.ip6s_total++;
  390 
  391 #ifndef PULLDOWN_TEST
  392         /*
  393          * L2 bridge code and some other code can return mbuf chain
  394          * that does not conform to KAME requirement.  too bad.
  395          * XXX: fails to join if interface MTU > MCLBYTES.  jumbogram?
  396          */
  397         if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) {
  398                 struct mbuf *n;
  399 
  400                 MGETHDR(n, M_DONTWAIT, MT_HEADER);
  401                 if (n)
  402                         M_MOVE_PKTHDR(n, m);
  403                 if (n && n->m_pkthdr.len > MHLEN) {
  404                         MCLGET(n, M_DONTWAIT);
  405                         if ((n->m_flags & M_EXT) == 0) {
  406                                 m_freem(n);
  407                                 n = NULL;
  408                         }
  409                 }
  410                 if (n == NULL) {
  411                         m_freem(m);
  412                         return; /* ENOBUFS */
  413                 }
  414 
  415                 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t));
  416                 n->m_len = n->m_pkthdr.len;
  417                 m_freem(m);
  418                 m = n;
  419         }
  420         IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /* nothing */);
  421 #endif
  422 
  423         if (m->m_len < sizeof(struct ip6_hdr)) {
  424                 struct ifnet *inifp;
  425                 inifp = m->m_pkthdr.rcvif;
  426                 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) {
  427                         V_ip6stat.ip6s_toosmall++;
  428                         in6_ifstat_inc(inifp, ifs6_in_hdrerr);
  429                         return;
  430                 }
  431         }
  432 
  433         ip6 = mtod(m, struct ip6_hdr *);
  434 
  435         if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
  436                 V_ip6stat.ip6s_badvers++;
  437                 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
  438                 goto bad;
  439         }
  440 
  441         V_ip6stat.ip6s_nxthist[ip6->ip6_nxt]++;
  442 
  443         /*
  444          * Check against address spoofing/corruption.
  445          */
  446         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) ||
  447             IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) {
  448                 /*
  449                  * XXX: "badscope" is not very suitable for a multicast source.
  450                  */
  451                 V_ip6stat.ip6s_badscope++;
  452                 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
  453                 goto bad;
  454         }
  455         if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) &&
  456             !(m->m_flags & M_LOOP)) {
  457                 /*
  458                  * In this case, the packet should come from the loopback
  459                  * interface.  However, we cannot just check the if_flags,
  460                  * because ip6_mloopback() passes the "actual" interface
  461                  * as the outgoing/incoming interface.
  462                  */
  463                 V_ip6stat.ip6s_badscope++;
  464                 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
  465                 goto bad;
  466         }
  467 
  468 #ifdef ALTQ
  469         if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) {
  470                 /* packet is dropped by traffic conditioner */
  471                 return;
  472         }
  473 #endif
  474         /*
  475          * The following check is not documented in specs.  A malicious
  476          * party may be able to use IPv4 mapped addr to confuse tcp/udp stack
  477          * and bypass security checks (act as if it was from 127.0.0.1 by using
  478          * IPv6 src ::ffff:127.0.0.1).  Be cautious.
  479          *
  480          * This check chokes if we are in an SIIT cloud.  As none of BSDs
  481          * support IPv4-less kernel compilation, we cannot support SIIT
  482          * environment at all.  So, it makes more sense for us to reject any
  483          * malicious packets for non-SIIT environment, than try to do a
  484          * partial support for SIIT environment.
  485          */
  486         if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
  487             IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
  488                 V_ip6stat.ip6s_badscope++;
  489                 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
  490                 goto bad;
  491         }
  492 #if 0
  493         /*
  494          * Reject packets with IPv4 compatible addresses (auto tunnel).
  495          *
  496          * The code forbids auto tunnel relay case in RFC1933 (the check is
  497          * stronger than RFC1933).  We may want to re-enable it if mech-xx
  498          * is revised to forbid relaying case.
  499          */
  500         if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) ||
  501             IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) {
  502                 V_ip6stat.ip6s_badscope++;
  503                 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
  504                 goto bad;
  505         }
  506 #endif
  507 
  508         /*
  509          * Run through list of hooks for input packets.
  510          *
  511          * NB: Beware of the destination address changing
  512          *     (e.g. by NAT rewriting).  When this happens,
  513          *     tell ip6_forward to do the right thing.
  514          */
  515         odst = ip6->ip6_dst;
  516 
  517         /* Jump over all PFIL processing if hooks are not active. */
  518         if (!PFIL_HOOKED(&inet6_pfil_hook))
  519                 goto passin;
  520 
  521         if (pfil_run_hooks(&inet6_pfil_hook, &m, m->m_pkthdr.rcvif, PFIL_IN, NULL))
  522                 return;
  523         if (m == NULL)                  /* consumed by filter */
  524                 return;
  525         ip6 = mtod(m, struct ip6_hdr *);
  526         srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst);
  527 
  528 passin:
  529         /*
  530          * Disambiguate address scope zones (if there is ambiguity).
  531          * We first make sure that the original source or destination address
  532          * is not in our internal form for scoped addresses.  Such addresses
  533          * are not necessarily invalid spec-wise, but we cannot accept them due
  534          * to the usage conflict.
  535          * in6_setscope() then also checks and rejects the cases where src or
  536          * dst are the loopback address and the receiving interface
  537          * is not loopback.
  538          */
  539         if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) {
  540                 V_ip6stat.ip6s_badscope++; /* XXX */
  541                 goto bad;
  542         }
  543         if (in6_setscope(&ip6->ip6_src, m->m_pkthdr.rcvif, NULL) ||
  544             in6_setscope(&ip6->ip6_dst, m->m_pkthdr.rcvif, NULL)) {
  545                 V_ip6stat.ip6s_badscope++;
  546                 goto bad;
  547         }
  548 
  549         /*
  550          * Multicast check. Assume packet is for us to avoid
  551          * prematurely taking locks.
  552          */
  553         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
  554                 ours = 1;
  555                 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast);
  556                 deliverifp = m->m_pkthdr.rcvif;
  557                 goto hbhcheck;
  558         }
  559 
  560         /*
  561          *  Unicast check
  562          */
  563 
  564         bzero(&dst6, sizeof(dst6));
  565         dst6.sin6_family = AF_INET6;
  566         dst6.sin6_len = sizeof(struct sockaddr_in6);
  567         dst6.sin6_addr = ip6->ip6_dst;
  568         ifp = m->m_pkthdr.rcvif;
  569         IF_AFDATA_LOCK(ifp);
  570         lle = lla_lookup(LLTABLE6(ifp), 0,
  571              (struct sockaddr *)&dst6);
  572         IF_AFDATA_UNLOCK(ifp);
  573         if ((lle != NULL) && (lle->la_flags & LLE_IFADDR)) {
  574                 ours = 1;
  575                 deliverifp = ifp;
  576                 LLE_RUNLOCK(lle);
  577                 goto hbhcheck;
  578         }
  579         if (lle != NULL)
  580                 LLE_RUNLOCK(lle);
  581 
  582         dst = &rin6.ro_dst;
  583         dst->sin6_len = sizeof(struct sockaddr_in6);
  584         dst->sin6_family = AF_INET6;
  585         dst->sin6_addr = ip6->ip6_dst;
  586         rin6.ro_rt = rtalloc1((struct sockaddr *)dst, 0, 0);
  587         if (rin6.ro_rt)
  588                 RT_UNLOCK(rin6.ro_rt);
  589 
  590 #define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key))
  591 
  592         /*
  593          * Accept the packet if the forwarding interface to the destination
  594          * according to the routing table is the loopback interface,
  595          * unless the associated route has a gateway.
  596          * Note that this approach causes to accept a packet if there is a
  597          * route to the loopback interface for the destination of the packet.
  598          * But we think it's even useful in some situations, e.g. when using
  599          * a special daemon which wants to intercept the packet.
  600          *
  601          * XXX: some OSes automatically make a cloned route for the destination
  602          * of an outgoing packet.  If the outgoing interface of the packet
  603          * is a loopback one, the kernel would consider the packet to be
  604          * accepted, even if we have no such address assinged on the interface.
  605          * We check the cloned flag of the route entry to reject such cases,
  606          * assuming that route entries for our own addresses are not made by
  607          * cloning (it should be true because in6_addloop explicitly installs
  608          * the host route).  However, we might have to do an explicit check
  609          * while it would be less efficient.  Or, should we rather install a
  610          * reject route for such a case?
  611          */
  612         if (rin6.ro_rt &&
  613             (rin6.ro_rt->rt_flags &
  614              (RTF_HOST|RTF_GATEWAY)) == RTF_HOST &&
  615 #ifdef RTF_WASCLONED
  616             !(rin6.ro_rt->rt_flags & RTF_WASCLONED) &&
  617 #endif
  618 #ifdef RTF_CLONED
  619             !(rin6.ro_rt->rt_flags & RTF_CLONED) &&
  620 #endif
  621 #if 0
  622             /*
  623              * The check below is redundant since the comparison of
  624              * the destination and the key of the rtentry has
  625              * already done through looking up the routing table.
  626              */
  627             IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
  628             &rt6_key(rin6.ro_rt)->sin6_addr)
  629 #endif
  630             rin6.ro_rt->rt_ifp->if_type == IFT_LOOP) {
  631                 int free_ia6 = 0;
  632                 struct in6_ifaddr *ia6;
  633 
  634                 /*
  635                  * found the loopback route to the interface address
  636                  */
  637                 if (rin6.ro_rt->rt_gateway->sa_family == AF_LINK) {
  638                         struct sockaddr_in6 dest6;
  639 
  640                         bzero(&dest6, sizeof(dest6));
  641                         dest6.sin6_family = AF_INET6;
  642                         dest6.sin6_len = sizeof(dest6);
  643                         dest6.sin6_addr = ip6->ip6_dst;
  644                         ia6 = (struct in6_ifaddr *)
  645                             ifa_ifwithaddr((struct sockaddr *)&dest6);
  646                         if (ia6 == NULL)
  647                                 goto bad;
  648                         free_ia6 = 1;
  649                 }
  650                 else
  651                         ia6 = (struct in6_ifaddr *)rin6.ro_rt->rt_ifa;
  652 
  653                 /*
  654                  * record address information into m_tag.
  655                  */
  656                 (void)ip6_setdstifaddr(m, ia6);
  657 
  658                 /*
  659                  * packets to a tentative, duplicated, or somehow invalid
  660                  * address must not be accepted.
  661                  */
  662                 if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) {
  663                         /* this address is ready */
  664                         ours = 1;
  665                         deliverifp = ia6->ia_ifp;       /* correct? */
  666                         /* Count the packet in the ip address stats */
  667                         ia6->ia_ifa.if_ipackets++;
  668                         ia6->ia_ifa.if_ibytes += m->m_pkthdr.len;
  669                         if (ia6 != NULL && free_ia6 != 0)
  670                                 ifa_free(&ia6->ia_ifa);
  671                         goto hbhcheck;
  672                 } else {
  673                         char ip6bufs[INET6_ADDRSTRLEN];
  674                         char ip6bufd[INET6_ADDRSTRLEN];
  675                         /* address is not ready, so discard the packet. */
  676                         nd6log((LOG_INFO,
  677                             "ip6_input: packet to an unready address %s->%s\n",
  678                             ip6_sprintf(ip6bufs, &ip6->ip6_src),
  679                             ip6_sprintf(ip6bufd, &ip6->ip6_dst)));
  680 
  681                         if (ia6 != NULL && free_ia6 != 0)
  682                                 ifa_free(&ia6->ia_ifa);
  683                         goto bad;
  684                 }
  685         }
  686 
  687         /*
  688          * FAITH (Firewall Aided Internet Translator)
  689          */
  690         if (V_ip6_keepfaith) {
  691                 if (rin6.ro_rt && rin6.ro_rt->rt_ifp &&
  692                     rin6.ro_rt->rt_ifp->if_type == IFT_FAITH) {
  693                         /* XXX do we need more sanity checks? */
  694                         ours = 1;
  695                         deliverifp = rin6.ro_rt->rt_ifp; /* faith */
  696                         goto hbhcheck;
  697                 }
  698         }
  699 
  700         /*
  701          * Now there is no reason to process the packet if it's not our own
  702          * and we're not a router.
  703          */
  704         if (!V_ip6_forwarding) {
  705                 V_ip6stat.ip6s_cantforward++;
  706                 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
  707                 goto bad;
  708         }
  709 
  710   hbhcheck:
  711         /*
  712          * record address information into m_tag, if we don't have one yet.
  713          * note that we are unable to record it, if the address is not listed
  714          * as our interface address (e.g. multicast addresses, addresses
  715          * within FAITH prefixes and such).
  716          */
  717         if (deliverifp && !ip6_getdstifaddr(m)) {
  718                 struct in6_ifaddr *ia6;
  719 
  720                 ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst);
  721                 if (ia6) {
  722                         if (!ip6_setdstifaddr(m, ia6)) {
  723                                 /*
  724                                  * XXX maybe we should drop the packet here,
  725                                  * as we could not provide enough information
  726                                  * to the upper layers.
  727                                  */
  728                         }
  729                         ifa_free(&ia6->ia_ifa);
  730                 }
  731         }
  732 
  733         /*
  734          * Process Hop-by-Hop options header if it's contained.
  735          * m may be modified in ip6_hopopts_input().
  736          * If a JumboPayload option is included, plen will also be modified.
  737          */
  738         plen = (u_int32_t)ntohs(ip6->ip6_plen);
  739         if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
  740                 struct ip6_hbh *hbh;
  741 
  742                 if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) {
  743 #if 0   /*touches NULL pointer*/
  744                         in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
  745 #endif
  746                         goto out;       /* m have already been freed */
  747                 }
  748 
  749                 /* adjust pointer */
  750                 ip6 = mtod(m, struct ip6_hdr *);
  751 
  752                 /*
  753                  * if the payload length field is 0 and the next header field
  754                  * indicates Hop-by-Hop Options header, then a Jumbo Payload
  755                  * option MUST be included.
  756                  */
  757                 if (ip6->ip6_plen == 0 && plen == 0) {
  758                         /*
  759                          * Note that if a valid jumbo payload option is
  760                          * contained, ip6_hopopts_input() must set a valid
  761                          * (non-zero) payload length to the variable plen.
  762                          */
  763                         V_ip6stat.ip6s_badoptions++;
  764                         in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
  765                         in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
  766                         icmp6_error(m, ICMP6_PARAM_PROB,
  767                                     ICMP6_PARAMPROB_HEADER,
  768                                     (caddr_t)&ip6->ip6_plen - (caddr_t)ip6);
  769                         goto out;
  770                 }
  771 #ifndef PULLDOWN_TEST
  772                 /* ip6_hopopts_input() ensures that mbuf is contiguous */
  773                 hbh = (struct ip6_hbh *)(ip6 + 1);
  774 #else
  775                 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
  776                         sizeof(struct ip6_hbh));
  777                 if (hbh == NULL) {
  778                         V_ip6stat.ip6s_tooshort++;
  779                         goto out;
  780                 }
  781 #endif
  782                 nxt = hbh->ip6h_nxt;
  783 
  784                 /*
  785                  * If we are acting as a router and the packet contains a
  786                  * router alert option, see if we know the option value.
  787                  * Currently, we only support the option value for MLD, in which
  788                  * case we should pass the packet to the multicast routing
  789                  * daemon.
  790                  */
  791                 if (rtalert != ~0) {
  792                         switch (rtalert) {
  793                         case IP6OPT_RTALERT_MLD:
  794                                 if (V_ip6_forwarding)
  795                                         ours = 1;
  796                                 break;
  797                         default:
  798                                 /*
  799                                  * RFC2711 requires unrecognized values must be
  800                                  * silently ignored.
  801                                  */
  802                                 break;
  803                         }
  804                 }
  805         } else
  806                 nxt = ip6->ip6_nxt;
  807 
  808         /*
  809          * Check that the amount of data in the buffers
  810          * is as at least much as the IPv6 header would have us expect.
  811          * Trim mbufs if longer than we expect.
  812          * Drop packet if shorter than we expect.
  813          */
  814         if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) {
  815                 V_ip6stat.ip6s_tooshort++;
  816                 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
  817                 goto bad;
  818         }
  819         if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) {
  820                 if (m->m_len == m->m_pkthdr.len) {
  821                         m->m_len = sizeof(struct ip6_hdr) + plen;
  822                         m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen;
  823                 } else
  824                         m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len);
  825         }
  826 
  827         /*
  828          * Forward if desirable.
  829          */
  830         if (V_ip6_mrouter &&
  831             IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
  832                 /*
  833                  * If we are acting as a multicast router, all
  834                  * incoming multicast packets are passed to the
  835                  * kernel-level multicast forwarding function.
  836                  * The packet is returned (relatively) intact; if
  837                  * ip6_mforward() returns a non-zero value, the packet
  838                  * must be discarded, else it may be accepted below.
  839                  *
  840                  * XXX TODO: Check hlim and multicast scope here to avoid
  841                  * unnecessarily calling into ip6_mforward().
  842                  */
  843                 if (ip6_mforward &&
  844                     ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) {
  845                         IP6STAT_INC(ip6s_cantforward);
  846                         in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
  847                         goto bad;
  848                 }
  849         } else if (!ours) {
  850                 ip6_forward(m, srcrt);
  851                 goto out;
  852         }
  853 
  854         ip6 = mtod(m, struct ip6_hdr *);
  855 
  856         /*
  857          * Malicious party may be able to use IPv4 mapped addr to confuse
  858          * tcp/udp stack and bypass security checks (act as if it was from
  859          * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1).  Be cautious.
  860          *
  861          * For SIIT end node behavior, you may want to disable the check.
  862          * However, you will  become vulnerable to attacks using IPv4 mapped
  863          * source.
  864          */
  865         if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
  866             IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
  867                 V_ip6stat.ip6s_badscope++;
  868                 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
  869                 goto bad;
  870         }
  871 
  872         /*
  873          * Tell launch routine the next header
  874          */
  875         V_ip6stat.ip6s_delivered++;
  876         in6_ifstat_inc(deliverifp, ifs6_in_deliver);
  877         nest = 0;
  878 
  879         while (nxt != IPPROTO_DONE) {
  880                 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) {
  881                         V_ip6stat.ip6s_toomanyhdr++;
  882                         goto bad;
  883                 }
  884 
  885                 /*
  886                  * protection against faulty packet - there should be
  887                  * more sanity checks in header chain processing.
  888                  */
  889                 if (m->m_pkthdr.len < off) {
  890                         V_ip6stat.ip6s_tooshort++;
  891                         in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
  892                         goto bad;
  893                 }
  894 
  895 #ifdef IPSEC
  896                 /*
  897                  * enforce IPsec policy checking if we are seeing last header.
  898                  * note that we do not visit this with protocols with pcb layer
  899                  * code - like udp/tcp/raw ip.
  900                  */
  901                 if (ip6_ipsec_input(m, nxt))
  902                         goto bad;
  903 #endif /* IPSEC */
  904 
  905                 /*
  906                  * Use mbuf flags to propagate Router Alert option to
  907                  * ICMPv6 layer, as hop-by-hop options have been stripped.
  908                  */
  909                 if (nxt == IPPROTO_ICMPV6 && rtalert != ~0)
  910                         m->m_flags |= M_RTALERT_MLD;
  911 
  912                 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt);
  913         }
  914         goto out;
  915 bad:
  916         m_freem(m);
  917 out:
  918         if (rin6.ro_rt)
  919                 RTFREE(rin6.ro_rt);
  920 }
  921 
  922 /*
  923  * set/grab in6_ifaddr correspond to IPv6 destination address.
  924  * XXX backward compatibility wrapper
  925  *
  926  * XXXRW: We should bump the refcount on ia6 before sticking it in the m_tag,
  927  * and then bump it when the tag is copied, and release it when the tag is
  928  * freed.  Unfortunately, m_tags don't support deep copies (yet), so instead
  929  * we just bump the ia refcount when we receive it.  This should be fixed.
  930  */
  931 static struct ip6aux *
  932 ip6_setdstifaddr(struct mbuf *m, struct in6_ifaddr *ia6)
  933 {
  934         struct ip6aux *ip6a;
  935 
  936         ip6a = ip6_addaux(m);
  937         if (ip6a)
  938                 ip6a->ip6a_dstia6 = ia6;
  939         return ip6a;    /* NULL if failed to set */
  940 }
  941 
  942 struct in6_ifaddr *
  943 ip6_getdstifaddr(struct mbuf *m)
  944 {
  945         struct ip6aux *ip6a;
  946         struct in6_ifaddr *ia;
  947 
  948         ip6a = ip6_findaux(m);
  949         if (ip6a) {
  950                 ia = ip6a->ip6a_dstia6;
  951                 ifa_ref(&ia->ia_ifa);
  952                 return ia;
  953         } else
  954                 return NULL;
  955 }
  956 
  957 /*
  958  * Hop-by-Hop options header processing. If a valid jumbo payload option is
  959  * included, the real payload length will be stored in plenp.
  960  *
  961  * rtalertp - XXX: should be stored more smart way
  962  */
  963 static int
  964 ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp,
  965     struct mbuf **mp, int *offp)
  966 {
  967         struct mbuf *m = *mp;
  968         int off = *offp, hbhlen;
  969         struct ip6_hbh *hbh;
  970         u_int8_t *opt;
  971 
  972         /* validation of the length of the header */
  973 #ifndef PULLDOWN_TEST
  974         IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1);
  975         hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
  976         hbhlen = (hbh->ip6h_len + 1) << 3;
  977 
  978         IP6_EXTHDR_CHECK(m, off, hbhlen, -1);
  979         hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
  980 #else
  981         IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m,
  982                 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh));
  983         if (hbh == NULL) {
  984                 V_ip6stat.ip6s_tooshort++;
  985                 return -1;
  986         }
  987         hbhlen = (hbh->ip6h_len + 1) << 3;
  988         IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
  989                 hbhlen);
  990         if (hbh == NULL) {
  991                 V_ip6stat.ip6s_tooshort++;
  992                 return -1;
  993         }
  994 #endif
  995         off += hbhlen;
  996         hbhlen -= sizeof(struct ip6_hbh);
  997         opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh);
  998 
  999         if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh),
 1000                                 hbhlen, rtalertp, plenp) < 0)
 1001                 return (-1);
 1002 
 1003         *offp = off;
 1004         *mp = m;
 1005         return (0);
 1006 }
 1007 
 1008 /*
 1009  * Search header for all Hop-by-hop options and process each option.
 1010  * This function is separate from ip6_hopopts_input() in order to
 1011  * handle a case where the sending node itself process its hop-by-hop
 1012  * options header. In such a case, the function is called from ip6_output().
 1013  *
 1014  * The function assumes that hbh header is located right after the IPv6 header
 1015  * (RFC2460 p7), opthead is pointer into data content in m, and opthead to
 1016  * opthead + hbhlen is located in continuous memory region.
 1017  */
 1018 int
 1019 ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen,
 1020     u_int32_t *rtalertp, u_int32_t *plenp)
 1021 {
 1022         struct ip6_hdr *ip6;
 1023         int optlen = 0;
 1024         u_int8_t *opt = opthead;
 1025         u_int16_t rtalert_val;
 1026         u_int32_t jumboplen;
 1027         const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh);
 1028 
 1029         for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) {
 1030                 switch (*opt) {
 1031                 case IP6OPT_PAD1:
 1032                         optlen = 1;
 1033                         break;
 1034                 case IP6OPT_PADN:
 1035                         if (hbhlen < IP6OPT_MINLEN) {
 1036                                 V_ip6stat.ip6s_toosmall++;
 1037                                 goto bad;
 1038                         }
 1039                         optlen = *(opt + 1) + 2;
 1040                         break;
 1041                 case IP6OPT_ROUTER_ALERT:
 1042                         /* XXX may need check for alignment */
 1043                         if (hbhlen < IP6OPT_RTALERT_LEN) {
 1044                                 V_ip6stat.ip6s_toosmall++;
 1045                                 goto bad;
 1046                         }
 1047                         if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) {
 1048                                 /* XXX stat */
 1049                                 icmp6_error(m, ICMP6_PARAM_PROB,
 1050                                     ICMP6_PARAMPROB_HEADER,
 1051                                     erroff + opt + 1 - opthead);
 1052                                 return (-1);
 1053                         }
 1054                         optlen = IP6OPT_RTALERT_LEN;
 1055                         bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2);
 1056                         *rtalertp = ntohs(rtalert_val);
 1057                         break;
 1058                 case IP6OPT_JUMBO:
 1059                         /* XXX may need check for alignment */
 1060                         if (hbhlen < IP6OPT_JUMBO_LEN) {
 1061                                 V_ip6stat.ip6s_toosmall++;
 1062                                 goto bad;
 1063                         }
 1064                         if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) {
 1065                                 /* XXX stat */
 1066                                 icmp6_error(m, ICMP6_PARAM_PROB,
 1067                                     ICMP6_PARAMPROB_HEADER,
 1068                                     erroff + opt + 1 - opthead);
 1069                                 return (-1);
 1070                         }
 1071                         optlen = IP6OPT_JUMBO_LEN;
 1072 
 1073                         /*
 1074                          * IPv6 packets that have non 0 payload length
 1075                          * must not contain a jumbo payload option.
 1076                          */
 1077                         ip6 = mtod(m, struct ip6_hdr *);
 1078                         if (ip6->ip6_plen) {
 1079                                 V_ip6stat.ip6s_badoptions++;
 1080                                 icmp6_error(m, ICMP6_PARAM_PROB,
 1081                                     ICMP6_PARAMPROB_HEADER,
 1082                                     erroff + opt - opthead);
 1083                                 return (-1);
 1084                         }
 1085 
 1086                         /*
 1087                          * We may see jumbolen in unaligned location, so
 1088                          * we'd need to perform bcopy().
 1089                          */
 1090                         bcopy(opt + 2, &jumboplen, sizeof(jumboplen));
 1091                         jumboplen = (u_int32_t)htonl(jumboplen);
 1092 
 1093 #if 1
 1094                         /*
 1095                          * if there are multiple jumbo payload options,
 1096                          * *plenp will be non-zero and the packet will be
 1097                          * rejected.
 1098                          * the behavior may need some debate in ipngwg -
 1099                          * multiple options does not make sense, however,
 1100                          * there's no explicit mention in specification.
 1101                          */
 1102                         if (*plenp != 0) {
 1103                                 V_ip6stat.ip6s_badoptions++;
 1104                                 icmp6_error(m, ICMP6_PARAM_PROB,
 1105                                     ICMP6_PARAMPROB_HEADER,
 1106                                     erroff + opt + 2 - opthead);
 1107                                 return (-1);
 1108                         }
 1109 #endif
 1110 
 1111                         /*
 1112                          * jumbo payload length must be larger than 65535.
 1113                          */
 1114                         if (jumboplen <= IPV6_MAXPACKET) {
 1115                                 V_ip6stat.ip6s_badoptions++;
 1116                                 icmp6_error(m, ICMP6_PARAM_PROB,
 1117                                     ICMP6_PARAMPROB_HEADER,
 1118                                     erroff + opt + 2 - opthead);
 1119                                 return (-1);
 1120                         }
 1121                         *plenp = jumboplen;
 1122 
 1123                         break;
 1124                 default:                /* unknown option */
 1125                         if (hbhlen < IP6OPT_MINLEN) {
 1126                                 V_ip6stat.ip6s_toosmall++;
 1127                                 goto bad;
 1128                         }
 1129                         optlen = ip6_unknown_opt(opt, m,
 1130                             erroff + opt - opthead);
 1131                         if (optlen == -1)
 1132                                 return (-1);
 1133                         optlen += 2;
 1134                         break;
 1135                 }
 1136         }
 1137 
 1138         return (0);
 1139 
 1140   bad:
 1141         m_freem(m);
 1142         return (-1);
 1143 }
 1144 
 1145 /*
 1146  * Unknown option processing.
 1147  * The third argument `off' is the offset from the IPv6 header to the option,
 1148  * which is necessary if the IPv6 header the and option header and IPv6 header
 1149  * is not continuous in order to return an ICMPv6 error.
 1150  */
 1151 int
 1152 ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off)
 1153 {
 1154         struct ip6_hdr *ip6;
 1155 
 1156         switch (IP6OPT_TYPE(*optp)) {
 1157         case IP6OPT_TYPE_SKIP: /* ignore the option */
 1158                 return ((int)*(optp + 1));
 1159         case IP6OPT_TYPE_DISCARD:       /* silently discard */
 1160                 m_freem(m);
 1161                 return (-1);
 1162         case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */
 1163                 V_ip6stat.ip6s_badoptions++;
 1164                 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off);
 1165                 return (-1);
 1166         case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */
 1167                 V_ip6stat.ip6s_badoptions++;
 1168                 ip6 = mtod(m, struct ip6_hdr *);
 1169                 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
 1170                     (m->m_flags & (M_BCAST|M_MCAST)))
 1171                         m_freem(m);
 1172                 else
 1173                         icmp6_error(m, ICMP6_PARAM_PROB,
 1174                                     ICMP6_PARAMPROB_OPTION, off);
 1175                 return (-1);
 1176         }
 1177 
 1178         m_freem(m);             /* XXX: NOTREACHED */
 1179         return (-1);
 1180 }
 1181 
 1182 /*
 1183  * Create the "control" list for this pcb.
 1184  * These functions will not modify mbuf chain at all.
 1185  *
 1186  * With KAME mbuf chain restriction:
 1187  * The routine will be called from upper layer handlers like tcp6_input().
 1188  * Thus the routine assumes that the caller (tcp6_input) have already
 1189  * called IP6_EXTHDR_CHECK() and all the extension headers are located in the
 1190  * very first mbuf on the mbuf chain.
 1191  *
 1192  * ip6_savecontrol_v4 will handle those options that are possible to be
 1193  * set on a v4-mapped socket.
 1194  * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those
 1195  * options and handle the v6-only ones itself.
 1196  */
 1197 struct mbuf **
 1198 ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp,
 1199     int *v4only)
 1200 {
 1201         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
 1202 
 1203 #ifdef SO_TIMESTAMP
 1204         if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) {
 1205                 struct timeval tv;
 1206 
 1207                 microtime(&tv);
 1208                 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
 1209                     SCM_TIMESTAMP, SOL_SOCKET);
 1210                 if (*mp)
 1211                         mp = &(*mp)->m_next;
 1212         }
 1213 #endif
 1214 
 1215         if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
 1216                 if (v4only != NULL)
 1217                         *v4only = 1;
 1218                 return (mp);
 1219         }
 1220 
 1221 #define IS2292(inp, x, y)       (((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y))
 1222         /* RFC 2292 sec. 5 */
 1223         if ((inp->inp_flags & IN6P_PKTINFO) != 0) {
 1224                 struct in6_pktinfo pi6;
 1225 
 1226                 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr));
 1227                 in6_clearscope(&pi6.ipi6_addr); /* XXX */
 1228                 pi6.ipi6_ifindex =
 1229                     (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0;
 1230 
 1231                 *mp = sbcreatecontrol((caddr_t) &pi6,
 1232                     sizeof(struct in6_pktinfo),
 1233                     IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6);
 1234                 if (*mp)
 1235                         mp = &(*mp)->m_next;
 1236         }
 1237 
 1238         if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) {
 1239                 int hlim = ip6->ip6_hlim & 0xff;
 1240 
 1241                 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int),
 1242                     IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT),
 1243                     IPPROTO_IPV6);
 1244                 if (*mp)
 1245                         mp = &(*mp)->m_next;
 1246         }
 1247 
 1248         if (v4only != NULL)
 1249                 *v4only = 0;
 1250         return (mp);
 1251 }
 1252 
 1253 void
 1254 ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp)
 1255 {
 1256         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
 1257         int v4only = 0;
 1258 
 1259         mp = ip6_savecontrol_v4(in6p, m, mp, &v4only);
 1260         if (v4only)
 1261                 return;
 1262 
 1263         if ((in6p->inp_flags & IN6P_TCLASS) != 0) {
 1264                 u_int32_t flowinfo;
 1265                 int tclass;
 1266 
 1267                 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK);
 1268                 flowinfo >>= 20;
 1269 
 1270                 tclass = flowinfo & 0xff;
 1271                 *mp = sbcreatecontrol((caddr_t) &tclass, sizeof(tclass),
 1272                     IPV6_TCLASS, IPPROTO_IPV6);
 1273                 if (*mp)
 1274                         mp = &(*mp)->m_next;
 1275         }
 1276 
 1277         /*
 1278          * IPV6_HOPOPTS socket option.  Recall that we required super-user
 1279          * privilege for the option (see ip6_ctloutput), but it might be too
 1280          * strict, since there might be some hop-by-hop options which can be
 1281          * returned to normal user.
 1282          * See also RFC 2292 section 6 (or RFC 3542 section 8).
 1283          */
 1284         if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) {
 1285                 /*
 1286                  * Check if a hop-by-hop options header is contatined in the
 1287                  * received packet, and if so, store the options as ancillary
 1288                  * data. Note that a hop-by-hop options header must be
 1289                  * just after the IPv6 header, which is assured through the
 1290                  * IPv6 input processing.
 1291                  */
 1292                 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
 1293                         struct ip6_hbh *hbh;
 1294                         int hbhlen = 0;
 1295 #ifdef PULLDOWN_TEST
 1296                         struct mbuf *ext;
 1297 #endif
 1298 
 1299 #ifndef PULLDOWN_TEST
 1300                         hbh = (struct ip6_hbh *)(ip6 + 1);
 1301                         hbhlen = (hbh->ip6h_len + 1) << 3;
 1302 #else
 1303                         ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr),
 1304                             ip6->ip6_nxt);
 1305                         if (ext == NULL) {
 1306                                 V_ip6stat.ip6s_tooshort++;
 1307                                 return;
 1308                         }
 1309                         hbh = mtod(ext, struct ip6_hbh *);
 1310                         hbhlen = (hbh->ip6h_len + 1) << 3;
 1311                         if (hbhlen != ext->m_len) {
 1312                                 m_freem(ext);
 1313                                 V_ip6stat.ip6s_tooshort++;
 1314                                 return;
 1315                         }
 1316 #endif
 1317 
 1318                         /*
 1319                          * XXX: We copy the whole header even if a
 1320                          * jumbo payload option is included, the option which
 1321                          * is to be removed before returning according to
 1322                          * RFC2292.
 1323                          * Note: this constraint is removed in RFC3542
 1324                          */
 1325                         *mp = sbcreatecontrol((caddr_t)hbh, hbhlen,
 1326                             IS2292(in6p, IPV6_2292HOPOPTS, IPV6_HOPOPTS),
 1327                             IPPROTO_IPV6);
 1328                         if (*mp)
 1329                                 mp = &(*mp)->m_next;
 1330 #ifdef PULLDOWN_TEST
 1331                         m_freem(ext);
 1332 #endif
 1333                 }
 1334         }
 1335 
 1336         if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) {
 1337                 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);
 1338 
 1339                 /*
 1340                  * Search for destination options headers or routing
 1341                  * header(s) through the header chain, and stores each
 1342                  * header as ancillary data.
 1343                  * Note that the order of the headers remains in
 1344                  * the chain of ancillary data.
 1345                  */
 1346                 while (1) {     /* is explicit loop prevention necessary? */
 1347                         struct ip6_ext *ip6e = NULL;
 1348                         int elen;
 1349 #ifdef PULLDOWN_TEST
 1350                         struct mbuf *ext = NULL;
 1351 #endif
 1352 
 1353                         /*
 1354                          * if it is not an extension header, don't try to
 1355                          * pull it from the chain.
 1356                          */
 1357                         switch (nxt) {
 1358                         case IPPROTO_DSTOPTS:
 1359                         case IPPROTO_ROUTING:
 1360                         case IPPROTO_HOPOPTS:
 1361                         case IPPROTO_AH: /* is it possible? */
 1362                                 break;
 1363                         default:
 1364                                 goto loopend;
 1365                         }
 1366 
 1367 #ifndef PULLDOWN_TEST
 1368                         if (off + sizeof(*ip6e) > m->m_len)
 1369                                 goto loopend;
 1370                         ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off);
 1371                         if (nxt == IPPROTO_AH)
 1372                                 elen = (ip6e->ip6e_len + 2) << 2;
 1373                         else
 1374                                 elen = (ip6e->ip6e_len + 1) << 3;
 1375                         if (off + elen > m->m_len)
 1376                                 goto loopend;
 1377 #else
 1378                         ext = ip6_pullexthdr(m, off, nxt);
 1379                         if (ext == NULL) {
 1380                                 V_ip6stat.ip6s_tooshort++;
 1381                                 return;
 1382                         }
 1383                         ip6e = mtod(ext, struct ip6_ext *);
 1384                         if (nxt == IPPROTO_AH)
 1385                                 elen = (ip6e->ip6e_len + 2) << 2;
 1386                         else
 1387                                 elen = (ip6e->ip6e_len + 1) << 3;
 1388                         if (elen != ext->m_len) {
 1389                                 m_freem(ext);
 1390                                 V_ip6stat.ip6s_tooshort++;
 1391                                 return;
 1392                         }
 1393 #endif
 1394 
 1395                         switch (nxt) {
 1396                         case IPPROTO_DSTOPTS:
 1397                                 if (!(in6p->inp_flags & IN6P_DSTOPTS))
 1398                                         break;
 1399 
 1400                                 *mp = sbcreatecontrol((caddr_t)ip6e, elen,
 1401                                     IS2292(in6p,
 1402                                         IPV6_2292DSTOPTS, IPV6_DSTOPTS),
 1403                                     IPPROTO_IPV6);
 1404                                 if (*mp)
 1405                                         mp = &(*mp)->m_next;
 1406                                 break;
 1407                         case IPPROTO_ROUTING:
 1408                                 if (!in6p->inp_flags & IN6P_RTHDR)
 1409                                         break;
 1410 
 1411                                 *mp = sbcreatecontrol((caddr_t)ip6e, elen,
 1412                                     IS2292(in6p, IPV6_2292RTHDR, IPV6_RTHDR),
 1413                                     IPPROTO_IPV6);
 1414                                 if (*mp)
 1415                                         mp = &(*mp)->m_next;
 1416                                 break;
 1417                         case IPPROTO_HOPOPTS:
 1418                         case IPPROTO_AH: /* is it possible? */
 1419                                 break;
 1420 
 1421                         default:
 1422                                 /*
 1423                                  * other cases have been filtered in the above.
 1424                                  * none will visit this case.  here we supply
 1425                                  * the code just in case (nxt overwritten or
 1426                                  * other cases).
 1427                                  */
 1428 #ifdef PULLDOWN_TEST
 1429                                 m_freem(ext);
 1430 #endif
 1431                                 goto loopend;
 1432 
 1433                         }
 1434 
 1435                         /* proceed with the next header. */
 1436                         off += elen;
 1437                         nxt = ip6e->ip6e_nxt;
 1438                         ip6e = NULL;
 1439 #ifdef PULLDOWN_TEST
 1440                         m_freem(ext);
 1441                         ext = NULL;
 1442 #endif
 1443                 }
 1444           loopend:
 1445                 ;
 1446         }
 1447 }
 1448 #undef IS2292
 1449 
 1450 void
 1451 ip6_notify_pmtu(struct inpcb *in6p, struct sockaddr_in6 *dst, u_int32_t *mtu)
 1452 {
 1453         struct socket *so;
 1454         struct mbuf *m_mtu;
 1455         struct ip6_mtuinfo mtuctl;
 1456 
 1457         so =  in6p->inp_socket;
 1458 
 1459         if (mtu == NULL)
 1460                 return;
 1461 
 1462 #ifdef DIAGNOSTIC
 1463         if (so == NULL)         /* I believe this is impossible */
 1464                 panic("ip6_notify_pmtu: socket is NULL");
 1465 #endif
 1466 
 1467         bzero(&mtuctl, sizeof(mtuctl)); /* zero-clear for safety */
 1468         mtuctl.ip6m_mtu = *mtu;
 1469         mtuctl.ip6m_addr = *dst;
 1470         if (sa6_recoverscope(&mtuctl.ip6m_addr))
 1471                 return;
 1472 
 1473         if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl),
 1474             IPV6_PATHMTU, IPPROTO_IPV6)) == NULL)
 1475                 return;
 1476 
 1477         if (sbappendaddr(&so->so_rcv, (struct sockaddr *)dst, NULL, m_mtu)
 1478             == 0) {
 1479                 m_freem(m_mtu);
 1480                 /* XXX: should count statistics */
 1481         } else
 1482                 sorwakeup(so);
 1483 
 1484         return;
 1485 }
 1486 
 1487 #ifdef PULLDOWN_TEST
 1488 /*
 1489  * pull single extension header from mbuf chain.  returns single mbuf that
 1490  * contains the result, or NULL on error.
 1491  */
 1492 static struct mbuf *
 1493 ip6_pullexthdr(struct mbuf *m, size_t off, int nxt)
 1494 {
 1495         struct ip6_ext ip6e;
 1496         size_t elen;
 1497         struct mbuf *n;
 1498 
 1499 #ifdef DIAGNOSTIC
 1500         switch (nxt) {
 1501         case IPPROTO_DSTOPTS:
 1502         case IPPROTO_ROUTING:
 1503         case IPPROTO_HOPOPTS:
 1504         case IPPROTO_AH: /* is it possible? */
 1505                 break;
 1506         default:
 1507                 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt);
 1508         }
 1509 #endif
 1510 
 1511         m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
 1512         if (nxt == IPPROTO_AH)
 1513                 elen = (ip6e.ip6e_len + 2) << 2;
 1514         else
 1515                 elen = (ip6e.ip6e_len + 1) << 3;
 1516 
 1517         MGET(n, M_DONTWAIT, MT_DATA);
 1518         if (n && elen >= MLEN) {
 1519                 MCLGET(n, M_DONTWAIT);
 1520                 if ((n->m_flags & M_EXT) == 0) {
 1521                         m_free(n);
 1522                         n = NULL;
 1523                 }
 1524         }
 1525         if (!n)
 1526                 return NULL;
 1527 
 1528         n->m_len = 0;
 1529         if (elen >= M_TRAILINGSPACE(n)) {
 1530                 m_free(n);
 1531                 return NULL;
 1532         }
 1533 
 1534         m_copydata(m, off, elen, mtod(n, caddr_t));
 1535         n->m_len = elen;
 1536         return n;
 1537 }
 1538 #endif
 1539 
 1540 /*
 1541  * Get pointer to the previous header followed by the header
 1542  * currently processed.
 1543  * XXX: This function supposes that
 1544  *      M includes all headers,
 1545  *      the next header field and the header length field of each header
 1546  *      are valid, and
 1547  *      the sum of each header length equals to OFF.
 1548  * Because of these assumptions, this function must be called very
 1549  * carefully. Moreover, it will not be used in the near future when
 1550  * we develop `neater' mechanism to process extension headers.
 1551  */
 1552 char *
 1553 ip6_get_prevhdr(struct mbuf *m, int off)
 1554 {
 1555         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
 1556 
 1557         if (off == sizeof(struct ip6_hdr))
 1558                 return (&ip6->ip6_nxt);
 1559         else {
 1560                 int len, nxt;
 1561                 struct ip6_ext *ip6e = NULL;
 1562 
 1563                 nxt = ip6->ip6_nxt;
 1564                 len = sizeof(struct ip6_hdr);
 1565                 while (len < off) {
 1566                         ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len);
 1567 
 1568                         switch (nxt) {
 1569                         case IPPROTO_FRAGMENT:
 1570                                 len += sizeof(struct ip6_frag);
 1571                                 break;
 1572                         case IPPROTO_AH:
 1573                                 len += (ip6e->ip6e_len + 2) << 2;
 1574                                 break;
 1575                         default:
 1576                                 len += (ip6e->ip6e_len + 1) << 3;
 1577                                 break;
 1578                         }
 1579                         nxt = ip6e->ip6e_nxt;
 1580                 }
 1581                 if (ip6e)
 1582                         return (&ip6e->ip6e_nxt);
 1583                 else
 1584                         return NULL;
 1585         }
 1586 }
 1587 
 1588 /*
 1589  * get next header offset.  m will be retained.
 1590  */
 1591 int
 1592 ip6_nexthdr(struct mbuf *m, int off, int proto, int *nxtp)
 1593 {
 1594         struct ip6_hdr ip6;
 1595         struct ip6_ext ip6e;
 1596         struct ip6_frag fh;
 1597 
 1598         /* just in case */
 1599         if (m == NULL)
 1600                 panic("ip6_nexthdr: m == NULL");
 1601         if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off)
 1602                 return -1;
 1603 
 1604         switch (proto) {
 1605         case IPPROTO_IPV6:
 1606                 if (m->m_pkthdr.len < off + sizeof(ip6))
 1607                         return -1;
 1608                 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6);
 1609                 if (nxtp)
 1610                         *nxtp = ip6.ip6_nxt;
 1611                 off += sizeof(ip6);
 1612                 return off;
 1613 
 1614         case IPPROTO_FRAGMENT:
 1615                 /*
 1616                  * terminate parsing if it is not the first fragment,
 1617                  * it does not make sense to parse through it.
 1618                  */
 1619                 if (m->m_pkthdr.len < off + sizeof(fh))
 1620                         return -1;
 1621                 m_copydata(m, off, sizeof(fh), (caddr_t)&fh);
 1622                 /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */
 1623                 if (fh.ip6f_offlg & IP6F_OFF_MASK)
 1624                         return -1;
 1625                 if (nxtp)
 1626                         *nxtp = fh.ip6f_nxt;
 1627                 off += sizeof(struct ip6_frag);
 1628                 return off;
 1629 
 1630         case IPPROTO_AH:
 1631                 if (m->m_pkthdr.len < off + sizeof(ip6e))
 1632                         return -1;
 1633                 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
 1634                 if (nxtp)
 1635                         *nxtp = ip6e.ip6e_nxt;
 1636                 off += (ip6e.ip6e_len + 2) << 2;
 1637                 return off;
 1638 
 1639         case IPPROTO_HOPOPTS:
 1640         case IPPROTO_ROUTING:
 1641         case IPPROTO_DSTOPTS:
 1642                 if (m->m_pkthdr.len < off + sizeof(ip6e))
 1643                         return -1;
 1644                 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
 1645                 if (nxtp)
 1646                         *nxtp = ip6e.ip6e_nxt;
 1647                 off += (ip6e.ip6e_len + 1) << 3;
 1648                 return off;
 1649 
 1650         case IPPROTO_NONE:
 1651         case IPPROTO_ESP:
 1652         case IPPROTO_IPCOMP:
 1653                 /* give up */
 1654                 return -1;
 1655 
 1656         default:
 1657                 return -1;
 1658         }
 1659 
 1660         return -1;
 1661 }
 1662 
 1663 /*
 1664  * get offset for the last header in the chain.  m will be kept untainted.
 1665  */
 1666 int
 1667 ip6_lasthdr(struct mbuf *m, int off, int proto, int *nxtp)
 1668 {
 1669         int newoff;
 1670         int nxt;
 1671 
 1672         if (!nxtp) {
 1673                 nxt = -1;
 1674                 nxtp = &nxt;
 1675         }
 1676         while (1) {
 1677                 newoff = ip6_nexthdr(m, off, proto, nxtp);
 1678                 if (newoff < 0)
 1679                         return off;
 1680                 else if (newoff < off)
 1681                         return -1;      /* invalid */
 1682                 else if (newoff == off)
 1683                         return newoff;
 1684 
 1685                 off = newoff;
 1686                 proto = *nxtp;
 1687         }
 1688 }
 1689 
 1690 struct ip6aux *
 1691 ip6_addaux(struct mbuf *m)
 1692 {
 1693         struct m_tag *mtag;
 1694 
 1695         mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL);
 1696         if (!mtag) {
 1697                 mtag = m_tag_get(PACKET_TAG_IPV6_INPUT, sizeof(struct ip6aux),
 1698                     M_NOWAIT);
 1699                 if (mtag) {
 1700                         m_tag_prepend(m, mtag);
 1701                         bzero(mtag + 1, sizeof(struct ip6aux));
 1702                 }
 1703         }
 1704         return mtag ? (struct ip6aux *)(mtag + 1) : NULL;
 1705 }
 1706 
 1707 struct ip6aux *
 1708 ip6_findaux(struct mbuf *m)
 1709 {
 1710         struct m_tag *mtag;
 1711 
 1712         mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL);
 1713         return mtag ? (struct ip6aux *)(mtag + 1) : NULL;
 1714 }
 1715 
 1716 void
 1717 ip6_delaux(struct mbuf *m)
 1718 {
 1719         struct m_tag *mtag;
 1720 
 1721         mtag = m_tag_find(m, PACKET_TAG_IPV6_INPUT, NULL);
 1722         if (mtag)
 1723                 m_tag_delete(m, mtag);
 1724 }
 1725 
 1726 /*
 1727  * System control for IP6
 1728  */
 1729 
 1730 u_char  inet6ctlerrmap[PRC_NCMDS] = {
 1731         0,              0,              0,              0,
 1732         0,              EMSGSIZE,       EHOSTDOWN,      EHOSTUNREACH,
 1733         EHOSTUNREACH,   EHOSTUNREACH,   ECONNREFUSED,   ECONNREFUSED,
 1734         EMSGSIZE,       EHOSTUNREACH,   0,              0,
 1735         0,              0,              0,              0,
 1736         ENOPROTOOPT
 1737 };

Cache object: 224a0b682ad6338b0aaa45dbd961f29e


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.