The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


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FreeBSD/Linux Kernel Cross Reference
sys/netinet6/icmp6.c

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    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: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun 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_icmp.c   8.2 (Berkeley) 1/4/94
   61  */
   62 
   63 #include <sys/cdefs.h>
   64 __FBSDID("$FreeBSD: releng/8.3/sys/netinet6/icmp6.c 229638 2012-01-05 19:56:54Z jhb $");
   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/domain.h>
   72 #include <sys/jail.h>
   73 #include <sys/kernel.h>
   74 #include <sys/lock.h>
   75 #include <sys/malloc.h>
   76 #include <sys/mbuf.h>
   77 #include <sys/proc.h>
   78 #include <sys/protosw.h>
   79 #include <sys/signalvar.h>
   80 #include <sys/socket.h>
   81 #include <sys/socketvar.h>
   82 #include <sys/sx.h>
   83 #include <sys/syslog.h>
   84 #include <sys/systm.h>
   85 #include <sys/time.h>
   86 
   87 #include <net/if.h>
   88 #include <net/if_dl.h>
   89 #include <net/if_llatbl.h>
   90 #include <net/if_types.h>
   91 #include <net/route.h>
   92 #include <net/vnet.h>
   93 
   94 #include <netinet/in.h>
   95 #include <netinet/in_pcb.h>
   96 #include <netinet/in_var.h>
   97 #include <netinet/ip6.h>
   98 #include <netinet/icmp6.h>
   99 #include <netinet/tcp_var.h>
  100 
  101 #include <netinet6/in6_ifattach.h>
  102 #include <netinet6/in6_pcb.h>
  103 #include <netinet6/ip6protosw.h>
  104 #include <netinet6/ip6_var.h>
  105 #include <netinet6/scope6_var.h>
  106 #include <netinet6/mld6_var.h>
  107 #include <netinet6/nd6.h>
  108 
  109 #ifdef IPSEC
  110 #include <netipsec/ipsec.h>
  111 #include <netipsec/key.h>
  112 #endif
  113 
  114 extern struct domain inet6domain;
  115 
  116 VNET_DEFINE(struct icmp6stat, icmp6stat);
  117 
  118 VNET_DECLARE(struct inpcbinfo, ripcbinfo);
  119 VNET_DECLARE(struct inpcbhead, ripcb);
  120 VNET_DECLARE(int, icmp6errppslim);
  121 static VNET_DEFINE(int, icmp6errpps_count) = 0;
  122 static VNET_DEFINE(struct timeval, icmp6errppslim_last);
  123 VNET_DECLARE(int, icmp6_nodeinfo);
  124 
  125 #define V_ripcbinfo                     VNET(ripcbinfo)
  126 #define V_ripcb                         VNET(ripcb)
  127 #define V_icmp6errppslim                VNET(icmp6errppslim)
  128 #define V_icmp6errpps_count             VNET(icmp6errpps_count)
  129 #define V_icmp6errppslim_last           VNET(icmp6errppslim_last)
  130 #define V_icmp6_nodeinfo                VNET(icmp6_nodeinfo)
  131 
  132 static void icmp6_errcount(struct icmp6errstat *, int, int);
  133 static int icmp6_rip6_input(struct mbuf **, int);
  134 static int icmp6_ratelimit(const struct in6_addr *, const int, const int);
  135 static const char *icmp6_redirect_diag __P((struct in6_addr *,
  136         struct in6_addr *, struct in6_addr *));
  137 static struct mbuf *ni6_input(struct mbuf *, int);
  138 static struct mbuf *ni6_nametodns(const char *, int, int);
  139 static int ni6_dnsmatch(const char *, int, const char *, int);
  140 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *,
  141                           struct ifnet **, struct in6_addr *));
  142 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
  143                                 struct ifnet *, int));
  144 static int icmp6_notify_error(struct mbuf **, int, int, int);
  145 
  146 /*
  147  * Kernel module interface for updating icmp6stat.  The argument is an index
  148  * into icmp6stat treated as an array of u_quad_t.  While this encodes the
  149  * general layout of icmp6stat into the caller, it doesn't encode its
  150  * location, so that future changes to add, for example, per-CPU stats
  151  * support won't cause binary compatibility problems for kernel modules.
  152  */
  153 void
  154 kmod_icmp6stat_inc(int statnum)
  155 {
  156 
  157         (*((u_quad_t *)&V_icmp6stat + statnum))++;
  158 }
  159 
  160 static void
  161 icmp6_errcount(struct icmp6errstat *stat, int type, int code)
  162 {
  163         switch (type) {
  164         case ICMP6_DST_UNREACH:
  165                 switch (code) {
  166                 case ICMP6_DST_UNREACH_NOROUTE:
  167                         stat->icp6errs_dst_unreach_noroute++;
  168                         return;
  169                 case ICMP6_DST_UNREACH_ADMIN:
  170                         stat->icp6errs_dst_unreach_admin++;
  171                         return;
  172                 case ICMP6_DST_UNREACH_BEYONDSCOPE:
  173                         stat->icp6errs_dst_unreach_beyondscope++;
  174                         return;
  175                 case ICMP6_DST_UNREACH_ADDR:
  176                         stat->icp6errs_dst_unreach_addr++;
  177                         return;
  178                 case ICMP6_DST_UNREACH_NOPORT:
  179                         stat->icp6errs_dst_unreach_noport++;
  180                         return;
  181                 }
  182                 break;
  183         case ICMP6_PACKET_TOO_BIG:
  184                 stat->icp6errs_packet_too_big++;
  185                 return;
  186         case ICMP6_TIME_EXCEEDED:
  187                 switch (code) {
  188                 case ICMP6_TIME_EXCEED_TRANSIT:
  189                         stat->icp6errs_time_exceed_transit++;
  190                         return;
  191                 case ICMP6_TIME_EXCEED_REASSEMBLY:
  192                         stat->icp6errs_time_exceed_reassembly++;
  193                         return;
  194                 }
  195                 break;
  196         case ICMP6_PARAM_PROB:
  197                 switch (code) {
  198                 case ICMP6_PARAMPROB_HEADER:
  199                         stat->icp6errs_paramprob_header++;
  200                         return;
  201                 case ICMP6_PARAMPROB_NEXTHEADER:
  202                         stat->icp6errs_paramprob_nextheader++;
  203                         return;
  204                 case ICMP6_PARAMPROB_OPTION:
  205                         stat->icp6errs_paramprob_option++;
  206                         return;
  207                 }
  208                 break;
  209         case ND_REDIRECT:
  210                 stat->icp6errs_redirect++;
  211                 return;
  212         }
  213         stat->icp6errs_unknown++;
  214 }
  215 
  216 /*
  217  * A wrapper function for icmp6_error() necessary when the erroneous packet
  218  * may not contain enough scope zone information.
  219  */
  220 void
  221 icmp6_error2(struct mbuf *m, int type, int code, int param,
  222     struct ifnet *ifp)
  223 {
  224         struct ip6_hdr *ip6;
  225 
  226         if (ifp == NULL)
  227                 return;
  228 
  229 #ifndef PULLDOWN_TEST
  230         IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
  231 #else
  232         if (m->m_len < sizeof(struct ip6_hdr)) {
  233                 m = m_pullup(m, sizeof(struct ip6_hdr));
  234                 if (m == NULL)
  235                         return;
  236         }
  237 #endif
  238 
  239         ip6 = mtod(m, struct ip6_hdr *);
  240 
  241         if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0)
  242                 return;
  243         if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
  244                 return;
  245 
  246         icmp6_error(m, type, code, param);
  247 }
  248 
  249 /*
  250  * Generate an error packet of type error in response to bad IP6 packet.
  251  */
  252 void
  253 icmp6_error(struct mbuf *m, int type, int code, int param)
  254 {
  255         struct ip6_hdr *oip6, *nip6;
  256         struct icmp6_hdr *icmp6;
  257         u_int preplen;
  258         int off;
  259         int nxt;
  260 
  261         ICMP6STAT_INC(icp6s_error);
  262 
  263         /* count per-type-code statistics */
  264         icmp6_errcount(&V_icmp6stat.icp6s_outerrhist, type, code);
  265 
  266 #ifdef M_DECRYPTED      /*not openbsd*/
  267         if (m->m_flags & M_DECRYPTED) {
  268                 ICMP6STAT_INC(icp6s_canterror);
  269                 goto freeit;
  270         }
  271 #endif
  272 
  273 #ifndef PULLDOWN_TEST
  274         IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
  275 #else
  276         if (m->m_len < sizeof(struct ip6_hdr)) {
  277                 m = m_pullup(m, sizeof(struct ip6_hdr));
  278                 if (m == NULL)
  279                         return;
  280         }
  281 #endif
  282         oip6 = mtod(m, struct ip6_hdr *);
  283 
  284         /*
  285          * If the destination address of the erroneous packet is a multicast
  286          * address, or the packet was sent using link-layer multicast,
  287          * we should basically suppress sending an error (RFC 2463, Section
  288          * 2.4).
  289          * We have two exceptions (the item e.2 in that section):
  290          * - the Packet Too Big message can be sent for path MTU discovery.
  291          * - the Parameter Problem Message that can be allowed an icmp6 error
  292          *   in the option type field.  This check has been done in
  293          *   ip6_unknown_opt(), so we can just check the type and code.
  294          */
  295         if ((m->m_flags & (M_BCAST|M_MCAST) ||
  296              IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
  297             (type != ICMP6_PACKET_TOO_BIG &&
  298              (type != ICMP6_PARAM_PROB ||
  299               code != ICMP6_PARAMPROB_OPTION)))
  300                 goto freeit;
  301 
  302         /*
  303          * RFC 2463, 2.4 (e.5): source address check.
  304          * XXX: the case of anycast source?
  305          */
  306         if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
  307             IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
  308                 goto freeit;
  309 
  310         /*
  311          * If we are about to send ICMPv6 against ICMPv6 error/redirect,
  312          * don't do it.
  313          */
  314         nxt = -1;
  315         off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
  316         if (off >= 0 && nxt == IPPROTO_ICMPV6) {
  317                 struct icmp6_hdr *icp;
  318 
  319 #ifndef PULLDOWN_TEST
  320                 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
  321                 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
  322 #else
  323                 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
  324                         sizeof(*icp));
  325                 if (icp == NULL) {
  326                         ICMP6STAT_INC(icp6s_tooshort);
  327                         return;
  328                 }
  329 #endif
  330                 if (icp->icmp6_type < ICMP6_ECHO_REQUEST ||
  331                     icp->icmp6_type == ND_REDIRECT) {
  332                         /*
  333                          * ICMPv6 error
  334                          * Special case: for redirect (which is
  335                          * informational) we must not send icmp6 error.
  336                          */
  337                         ICMP6STAT_INC(icp6s_canterror);
  338                         goto freeit;
  339                 } else {
  340                         /* ICMPv6 informational - send the error */
  341                 }
  342         } else {
  343                 /* non-ICMPv6 - send the error */
  344         }
  345 
  346         oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
  347 
  348         /* Finally, do rate limitation check. */
  349         if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
  350                 ICMP6STAT_INC(icp6s_toofreq);
  351                 goto freeit;
  352         }
  353 
  354         /*
  355          * OK, ICMP6 can be generated.
  356          */
  357 
  358         if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
  359                 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
  360 
  361         preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
  362         M_PREPEND(m, preplen, M_DONTWAIT);
  363         if (m && m->m_len < preplen)
  364                 m = m_pullup(m, preplen);
  365         if (m == NULL) {
  366                 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__));
  367                 return;
  368         }
  369 
  370         nip6 = mtod(m, struct ip6_hdr *);
  371         nip6->ip6_src  = oip6->ip6_src;
  372         nip6->ip6_dst  = oip6->ip6_dst;
  373 
  374         in6_clearscope(&oip6->ip6_src);
  375         in6_clearscope(&oip6->ip6_dst);
  376 
  377         icmp6 = (struct icmp6_hdr *)(nip6 + 1);
  378         icmp6->icmp6_type = type;
  379         icmp6->icmp6_code = code;
  380         icmp6->icmp6_pptr = htonl((u_int32_t)param);
  381 
  382         /*
  383          * icmp6_reflect() is designed to be in the input path.
  384          * icmp6_error() can be called from both input and output path,
  385          * and if we are in output path rcvif could contain bogus value.
  386          * clear m->m_pkthdr.rcvif for safety, we should have enough scope
  387          * information in ip header (nip6).
  388          */
  389         m->m_pkthdr.rcvif = NULL;
  390 
  391         ICMP6STAT_INC(icp6s_outhist[type]);
  392         icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */
  393 
  394         return;
  395 
  396   freeit:
  397         /*
  398          * If we can't tell whether or not we can generate ICMP6, free it.
  399          */
  400         m_freem(m);
  401 }
  402 
  403 /*
  404  * Process a received ICMP6 message.
  405  */
  406 int
  407 icmp6_input(struct mbuf **mp, int *offp, int proto)
  408 {
  409         struct mbuf *m = *mp, *n;
  410         struct ifnet *ifp;
  411         struct ip6_hdr *ip6, *nip6;
  412         struct icmp6_hdr *icmp6, *nicmp6;
  413         int off = *offp;
  414         int icmp6len = m->m_pkthdr.len - *offp;
  415         int code, sum, noff;
  416         char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
  417 
  418         ifp = m->m_pkthdr.rcvif;
  419 
  420 #ifndef PULLDOWN_TEST
  421         IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
  422         /* m might change if M_LOOP.  So, call mtod after this */
  423 #endif
  424 
  425         /*
  426          * Locate icmp6 structure in mbuf, and check
  427          * that not corrupted and of at least minimum length
  428          */
  429 
  430         ip6 = mtod(m, struct ip6_hdr *);
  431         if (icmp6len < sizeof(struct icmp6_hdr)) {
  432                 ICMP6STAT_INC(icp6s_tooshort);
  433                 goto freeit;
  434         }
  435 
  436         /*
  437          * Check multicast group membership.
  438          * Note: SSM filters are not applied for ICMPv6 traffic.
  439          */
  440         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
  441                 struct in6_multi        *inm;
  442 
  443                 inm = in6m_lookup(ifp, &ip6->ip6_dst);
  444                 if (inm == NULL) {
  445                         IP6STAT_INC(ip6s_notmember);
  446                         in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
  447                         goto freeit;
  448                 }
  449         }
  450 
  451         /*
  452          * calculate the checksum
  453          */
  454 #ifndef PULLDOWN_TEST
  455         icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
  456 #else
  457         IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
  458         if (icmp6 == NULL) {
  459                 ICMP6STAT_INC(icp6s_tooshort);
  460                 return IPPROTO_DONE;
  461         }
  462 #endif
  463         code = icmp6->icmp6_code;
  464 
  465         if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
  466                 nd6log((LOG_ERR,
  467                     "ICMP6 checksum error(%d|%x) %s\n",
  468                     icmp6->icmp6_type, sum,
  469                     ip6_sprintf(ip6bufs, &ip6->ip6_src)));
  470                 ICMP6STAT_INC(icp6s_checksum);
  471                 goto freeit;
  472         }
  473 
  474         if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) {
  475                 /*
  476                  * Deliver very specific ICMP6 type only.
  477                  * This is important to deliver TOOBIG.  Otherwise PMTUD
  478                  * will not work.
  479                  */
  480                 switch (icmp6->icmp6_type) {
  481                 case ICMP6_DST_UNREACH:
  482                 case ICMP6_PACKET_TOO_BIG:
  483                 case ICMP6_TIME_EXCEEDED:
  484                         break;
  485                 default:
  486                         goto freeit;
  487                 }
  488         }
  489 
  490         ICMP6STAT_INC(icp6s_inhist[icmp6->icmp6_type]);
  491         icmp6_ifstat_inc(ifp, ifs6_in_msg);
  492         if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
  493                 icmp6_ifstat_inc(ifp, ifs6_in_error);
  494 
  495         switch (icmp6->icmp6_type) {
  496         case ICMP6_DST_UNREACH:
  497                 icmp6_ifstat_inc(ifp, ifs6_in_dstunreach);
  498                 switch (code) {
  499                 case ICMP6_DST_UNREACH_NOROUTE:
  500                         code = PRC_UNREACH_NET;
  501                         break;
  502                 case ICMP6_DST_UNREACH_ADMIN:
  503                         icmp6_ifstat_inc(ifp, ifs6_in_adminprohib);
  504                         code = PRC_UNREACH_PROTOCOL; /* is this a good code? */
  505                         break;
  506                 case ICMP6_DST_UNREACH_ADDR:
  507                         code = PRC_HOSTDEAD;
  508                         break;
  509                 case ICMP6_DST_UNREACH_BEYONDSCOPE:
  510                         /* I mean "source address was incorrect." */
  511                         code = PRC_PARAMPROB;
  512                         break;
  513                 case ICMP6_DST_UNREACH_NOPORT:
  514                         code = PRC_UNREACH_PORT;
  515                         break;
  516                 default:
  517                         goto badcode;
  518                 }
  519                 goto deliver;
  520                 break;
  521 
  522         case ICMP6_PACKET_TOO_BIG:
  523                 icmp6_ifstat_inc(ifp, ifs6_in_pkttoobig);
  524 
  525                 /* validation is made in icmp6_mtudisc_update */
  526 
  527                 code = PRC_MSGSIZE;
  528 
  529                 /*
  530                  * Updating the path MTU will be done after examining
  531                  * intermediate extension headers.
  532                  */
  533                 goto deliver;
  534                 break;
  535 
  536         case ICMP6_TIME_EXCEEDED:
  537                 icmp6_ifstat_inc(ifp, ifs6_in_timeexceed);
  538                 switch (code) {
  539                 case ICMP6_TIME_EXCEED_TRANSIT:
  540                         code = PRC_TIMXCEED_INTRANS;
  541                         break;
  542                 case ICMP6_TIME_EXCEED_REASSEMBLY:
  543                         code = PRC_TIMXCEED_REASS;
  544                         break;
  545                 default:
  546                         goto badcode;
  547                 }
  548                 goto deliver;
  549                 break;
  550 
  551         case ICMP6_PARAM_PROB:
  552                 icmp6_ifstat_inc(ifp, ifs6_in_paramprob);
  553                 switch (code) {
  554                 case ICMP6_PARAMPROB_NEXTHEADER:
  555                         code = PRC_UNREACH_PROTOCOL;
  556                         break;
  557                 case ICMP6_PARAMPROB_HEADER:
  558                 case ICMP6_PARAMPROB_OPTION:
  559                         code = PRC_PARAMPROB;
  560                         break;
  561                 default:
  562                         goto badcode;
  563                 }
  564                 goto deliver;
  565                 break;
  566 
  567         case ICMP6_ECHO_REQUEST:
  568                 icmp6_ifstat_inc(ifp, ifs6_in_echo);
  569                 if (code != 0)
  570                         goto badcode;
  571                 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) {
  572                         /* Give up remote */
  573                         break;
  574                 }
  575                 if ((n->m_flags & M_EXT) != 0
  576                  || n->m_len < off + sizeof(struct icmp6_hdr)) {
  577                         struct mbuf *n0 = n;
  578                         const int maxlen = sizeof(*nip6) + sizeof(*nicmp6);
  579                         int n0len;
  580 
  581                         MGETHDR(n, M_DONTWAIT, n0->m_type);
  582                         n0len = n0->m_pkthdr.len;       /* save for use below */
  583                         if (n)
  584                                 M_MOVE_PKTHDR(n, n0);
  585                         if (n && maxlen >= MHLEN) {
  586                                 MCLGET(n, M_DONTWAIT);
  587                                 if ((n->m_flags & M_EXT) == 0) {
  588                                         m_free(n);
  589                                         n = NULL;
  590                                 }
  591                         }
  592                         if (n == NULL) {
  593                                 /* Give up remote */
  594                                 m_freem(n0);
  595                                 break;
  596                         }
  597                         /*
  598                          * Copy IPv6 and ICMPv6 only.
  599                          */
  600                         nip6 = mtod(n, struct ip6_hdr *);
  601                         bcopy(ip6, nip6, sizeof(struct ip6_hdr));
  602                         nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
  603                         bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
  604                         noff = sizeof(struct ip6_hdr);
  605                         /* new mbuf contains only ipv6+icmpv6 headers */
  606                         n->m_len = noff + sizeof(struct icmp6_hdr);
  607                         /*
  608                          * Adjust mbuf.  ip6_plen will be adjusted in
  609                          * ip6_output().
  610                          */
  611                         m_adj(n0, off + sizeof(struct icmp6_hdr));
  612                         /* recalculate complete packet size */
  613                         n->m_pkthdr.len = n0len + (noff - off);
  614                         n->m_next = n0;
  615                 } else {
  616                         nip6 = mtod(n, struct ip6_hdr *);
  617                         IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off,
  618                             sizeof(*nicmp6));
  619                         noff = off;
  620                 }
  621                 nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
  622                 nicmp6->icmp6_code = 0;
  623                 if (n) {
  624                         ICMP6STAT_INC(icp6s_reflect);
  625                         ICMP6STAT_INC(icp6s_outhist[ICMP6_ECHO_REPLY]);
  626                         icmp6_reflect(n, noff);
  627                 }
  628                 break;
  629 
  630         case ICMP6_ECHO_REPLY:
  631                 icmp6_ifstat_inc(ifp, ifs6_in_echoreply);
  632                 if (code != 0)
  633                         goto badcode;
  634                 break;
  635 
  636         case MLD_LISTENER_QUERY:
  637         case MLD_LISTENER_REPORT:
  638         case MLD_LISTENER_DONE:
  639         case MLDV2_LISTENER_REPORT:
  640                 /*
  641                  * Drop MLD traffic which is not link-local, has a hop limit
  642                  * of greater than 1 hop, or which does not have the
  643                  * IPv6 HBH Router Alert option.
  644                  * As IPv6 HBH options are stripped in ip6_input() we must
  645                  * check an mbuf header flag.
  646                  * XXX Should we also sanity check that these messages
  647                  * were directed to a link-local multicast prefix?
  648                  */
  649                 if ((ip6->ip6_hlim != 1) || (m->m_flags & M_RTALERT_MLD) == 0)
  650                         goto freeit;
  651                 if (mld_input(m, off, icmp6len) != 0)
  652                         return (IPPROTO_DONE);
  653                 /* m stays. */
  654                 break;
  655 
  656         case ICMP6_WRUREQUEST:  /* ICMP6_FQDN_QUERY */
  657             {
  658                 enum { WRU, FQDN } mode;
  659 
  660                 if (!V_icmp6_nodeinfo)
  661                         break;
  662 
  663                 if (icmp6len == sizeof(struct icmp6_hdr) + 4)
  664                         mode = WRU;
  665                 else if (icmp6len >= sizeof(struct icmp6_nodeinfo))
  666                         mode = FQDN;
  667                 else
  668                         goto badlen;
  669 
  670                 if (mode == FQDN) {
  671 #ifndef PULLDOWN_TEST
  672                         IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
  673                             IPPROTO_DONE);
  674 #endif
  675                         n = m_copy(m, 0, M_COPYALL);
  676                         if (n)
  677                                 n = ni6_input(n, off);
  678                         /* XXX meaningless if n == NULL */
  679                         noff = sizeof(struct ip6_hdr);
  680                 } else {
  681                         struct prison *pr;
  682                         u_char *p;
  683                         int maxlen, maxhlen, hlen;
  684 
  685                         /*
  686                          * XXX: this combination of flags is pointless,
  687                          * but should we keep this for compatibility?
  688                          */
  689                         if ((V_icmp6_nodeinfo & 5) != 5)
  690                                 break;
  691 
  692                         if (code != 0)
  693                                 goto badcode;
  694                         maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4;
  695                         if (maxlen >= MCLBYTES) {
  696                                 /* Give up remote */
  697                                 break;
  698                         }
  699                         MGETHDR(n, M_DONTWAIT, m->m_type);
  700                         if (n && maxlen > MHLEN) {
  701                                 MCLGET(n, M_DONTWAIT);
  702                                 if ((n->m_flags & M_EXT) == 0) {
  703                                         m_free(n);
  704                                         n = NULL;
  705                                 }
  706                         }
  707                         if (n && !m_dup_pkthdr(n, m, M_DONTWAIT)) {
  708                                 /*
  709                                  * Previous code did a blind M_COPY_PKTHDR
  710                                  * and said "just for rcvif".  If true, then
  711                                  * we could tolerate the dup failing (due to
  712                                  * the deep copy of the tag chain).  For now
  713                                  * be conservative and just fail.
  714                                  */
  715                                 m_free(n);
  716                                 n = NULL;
  717                         }
  718                         if (n == NULL) {
  719                                 /* Give up remote */
  720                                 break;
  721                         }
  722                         n->m_pkthdr.rcvif = NULL;
  723                         n->m_len = 0;
  724                         maxhlen = M_TRAILINGSPACE(n) - maxlen;
  725                         pr = curthread->td_ucred->cr_prison;
  726                         mtx_lock(&pr->pr_mtx);
  727                         hlen = strlen(pr->pr_hostname);
  728                         if (maxhlen > hlen)
  729                                 maxhlen = hlen;
  730                         /*
  731                          * Copy IPv6 and ICMPv6 only.
  732                          */
  733                         nip6 = mtod(n, struct ip6_hdr *);
  734                         bcopy(ip6, nip6, sizeof(struct ip6_hdr));
  735                         nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
  736                         bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
  737                         p = (u_char *)(nicmp6 + 1);
  738                         bzero(p, 4);
  739                         /* meaningless TTL */
  740                         bcopy(pr->pr_hostname, p + 4, maxhlen);
  741                         mtx_unlock(&pr->pr_mtx);
  742                         noff = sizeof(struct ip6_hdr);
  743                         n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
  744                                 sizeof(struct icmp6_hdr) + 4 + maxhlen;
  745                         nicmp6->icmp6_type = ICMP6_WRUREPLY;
  746                         nicmp6->icmp6_code = 0;
  747                 }
  748                 if (n) {
  749                         ICMP6STAT_INC(icp6s_reflect);
  750                         ICMP6STAT_INC(icp6s_outhist[ICMP6_WRUREPLY]);
  751                         icmp6_reflect(n, noff);
  752                 }
  753                 break;
  754             }
  755 
  756         case ICMP6_WRUREPLY:
  757                 if (code != 0)
  758                         goto badcode;
  759                 break;
  760 
  761         case ND_ROUTER_SOLICIT:
  762                 icmp6_ifstat_inc(ifp, ifs6_in_routersolicit);
  763                 if (code != 0)
  764                         goto badcode;
  765                 if (icmp6len < sizeof(struct nd_router_solicit))
  766                         goto badlen;
  767                 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
  768                         /* give up local */
  769                         nd6_rs_input(m, off, icmp6len);
  770                         m = NULL;
  771                         goto freeit;
  772                 }
  773                 nd6_rs_input(n, off, icmp6len);
  774                 /* m stays. */
  775                 break;
  776 
  777         case ND_ROUTER_ADVERT:
  778                 icmp6_ifstat_inc(ifp, ifs6_in_routeradvert);
  779                 if (code != 0)
  780                         goto badcode;
  781                 if (icmp6len < sizeof(struct nd_router_advert))
  782                         goto badlen;
  783                 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
  784                         /* give up local */
  785                         nd6_ra_input(m, off, icmp6len);
  786                         m = NULL;
  787                         goto freeit;
  788                 }
  789                 nd6_ra_input(n, off, icmp6len);
  790                 /* m stays. */
  791                 break;
  792 
  793         case ND_NEIGHBOR_SOLICIT:
  794                 icmp6_ifstat_inc(ifp, ifs6_in_neighborsolicit);
  795                 if (code != 0)
  796                         goto badcode;
  797                 if (icmp6len < sizeof(struct nd_neighbor_solicit))
  798                         goto badlen;
  799                 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
  800                         /* give up local */
  801                         nd6_ns_input(m, off, icmp6len);
  802                         m = NULL;
  803                         goto freeit;
  804                 }
  805                 nd6_ns_input(n, off, icmp6len);
  806                 /* m stays. */
  807                 break;
  808 
  809         case ND_NEIGHBOR_ADVERT:
  810                 icmp6_ifstat_inc(ifp, ifs6_in_neighboradvert);
  811                 if (code != 0)
  812                         goto badcode;
  813                 if (icmp6len < sizeof(struct nd_neighbor_advert))
  814                         goto badlen;
  815                 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
  816                         /* give up local */
  817                         nd6_na_input(m, off, icmp6len);
  818                         m = NULL;
  819                         goto freeit;
  820                 }
  821                 nd6_na_input(n, off, icmp6len);
  822                 /* m stays. */
  823                 break;
  824 
  825         case ND_REDIRECT:
  826                 icmp6_ifstat_inc(ifp, ifs6_in_redirect);
  827                 if (code != 0)
  828                         goto badcode;
  829                 if (icmp6len < sizeof(struct nd_redirect))
  830                         goto badlen;
  831                 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
  832                         /* give up local */
  833                         icmp6_redirect_input(m, off);
  834                         m = NULL;
  835                         goto freeit;
  836                 }
  837                 icmp6_redirect_input(n, off);
  838                 /* m stays. */
  839                 break;
  840 
  841         case ICMP6_ROUTER_RENUMBERING:
  842                 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
  843                     code != ICMP6_ROUTER_RENUMBERING_RESULT)
  844                         goto badcode;
  845                 if (icmp6len < sizeof(struct icmp6_router_renum))
  846                         goto badlen;
  847                 break;
  848 
  849         default:
  850                 nd6log((LOG_DEBUG,
  851                     "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
  852                     icmp6->icmp6_type, ip6_sprintf(ip6bufs, &ip6->ip6_src),
  853                     ip6_sprintf(ip6bufd, &ip6->ip6_dst),
  854                     ifp ? ifp->if_index : 0));
  855                 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
  856                         /* ICMPv6 error: MUST deliver it by spec... */
  857                         code = PRC_NCMDS;
  858                         /* deliver */
  859                 } else {
  860                         /* ICMPv6 informational: MUST not deliver */
  861                         break;
  862                 }
  863         deliver:
  864                 if (icmp6_notify_error(&m, off, icmp6len, code) != 0) {
  865                         /* In this case, m should've been freed. */
  866                         return (IPPROTO_DONE);
  867                 }
  868                 break;
  869 
  870         badcode:
  871                 ICMP6STAT_INC(icp6s_badcode);
  872                 break;
  873 
  874         badlen:
  875                 ICMP6STAT_INC(icp6s_badlen);
  876                 break;
  877         }
  878 
  879         /* deliver the packet to appropriate sockets */
  880         icmp6_rip6_input(&m, *offp);
  881 
  882         return IPPROTO_DONE;
  883 
  884  freeit:
  885         m_freem(m);
  886         return IPPROTO_DONE;
  887 }
  888 
  889 static int
  890 icmp6_notify_error(struct mbuf **mp, int off, int icmp6len, int code)
  891 {
  892         struct mbuf *m = *mp;
  893         struct icmp6_hdr *icmp6;
  894         struct ip6_hdr *eip6;
  895         u_int32_t notifymtu;
  896         struct sockaddr_in6 icmp6src, icmp6dst;
  897 
  898         if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
  899                 ICMP6STAT_INC(icp6s_tooshort);
  900                 goto freeit;
  901         }
  902 #ifndef PULLDOWN_TEST
  903         IP6_EXTHDR_CHECK(m, off,
  904             sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1);
  905         icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
  906 #else
  907         IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
  908             sizeof(*icmp6) + sizeof(struct ip6_hdr));
  909         if (icmp6 == NULL) {
  910                 ICMP6STAT_INC(icp6s_tooshort);
  911                 return (-1);
  912         }
  913 #endif
  914         eip6 = (struct ip6_hdr *)(icmp6 + 1);
  915 
  916         /* Detect the upper level protocol */
  917         {
  918                 void (*ctlfunc)(int, struct sockaddr *, void *);
  919                 u_int8_t nxt = eip6->ip6_nxt;
  920                 int eoff = off + sizeof(struct icmp6_hdr) +
  921                     sizeof(struct ip6_hdr);
  922                 struct ip6ctlparam ip6cp;
  923                 struct in6_addr *finaldst = NULL;
  924                 int icmp6type = icmp6->icmp6_type;
  925                 struct ip6_frag *fh;
  926                 struct ip6_rthdr *rth;
  927                 struct ip6_rthdr0 *rth0;
  928                 int rthlen;
  929 
  930                 while (1) { /* XXX: should avoid infinite loop explicitly? */
  931                         struct ip6_ext *eh;
  932 
  933                         switch (nxt) {
  934                         case IPPROTO_HOPOPTS:
  935                         case IPPROTO_DSTOPTS:
  936                         case IPPROTO_AH:
  937 #ifndef PULLDOWN_TEST
  938                                 IP6_EXTHDR_CHECK(m, 0,
  939                                     eoff + sizeof(struct ip6_ext), -1);
  940                                 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff);
  941 #else
  942                                 IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
  943                                     eoff, sizeof(*eh));
  944                                 if (eh == NULL) {
  945                                         ICMP6STAT_INC(icp6s_tooshort);
  946                                         return (-1);
  947                                 }
  948 #endif
  949 
  950                                 if (nxt == IPPROTO_AH)
  951                                         eoff += (eh->ip6e_len + 2) << 2;
  952                                 else
  953                                         eoff += (eh->ip6e_len + 1) << 3;
  954                                 nxt = eh->ip6e_nxt;
  955                                 break;
  956                         case IPPROTO_ROUTING:
  957                                 /*
  958                                  * When the erroneous packet contains a
  959                                  * routing header, we should examine the
  960                                  * header to determine the final destination.
  961                                  * Otherwise, we can't properly update
  962                                  * information that depends on the final
  963                                  * destination (e.g. path MTU).
  964                                  */
  965 #ifndef PULLDOWN_TEST
  966                                 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1);
  967                                 rth = (struct ip6_rthdr *)
  968                                     (mtod(m, caddr_t) + eoff);
  969 #else
  970                                 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m,
  971                                     eoff, sizeof(*rth));
  972                                 if (rth == NULL) {
  973                                         ICMP6STAT_INC(icp6s_tooshort);
  974                                         return (-1);
  975                                 }
  976 #endif
  977                                 rthlen = (rth->ip6r_len + 1) << 3;
  978                                 /*
  979                                  * XXX: currently there is no
  980                                  * officially defined type other
  981                                  * than type-0.
  982                                  * Note that if the segment left field
  983                                  * is 0, all intermediate hops must
  984                                  * have been passed.
  985                                  */
  986                                 if (rth->ip6r_segleft &&
  987                                     rth->ip6r_type == IPV6_RTHDR_TYPE_0) {
  988                                         int hops;
  989 
  990 #ifndef PULLDOWN_TEST
  991                                         IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1);
  992                                         rth0 = (struct ip6_rthdr0 *)
  993                                             (mtod(m, caddr_t) + eoff);
  994 #else
  995                                         IP6_EXTHDR_GET(rth0,
  996                                             struct ip6_rthdr0 *, m,
  997                                             eoff, rthlen);
  998                                         if (rth0 == NULL) {
  999                                                 ICMP6STAT_INC(icp6s_tooshort);
 1000                                                 return (-1);
 1001                                         }
 1002 #endif
 1003                                         /* just ignore a bogus header */
 1004                                         if ((rth0->ip6r0_len % 2) == 0 &&
 1005                                             (hops = rth0->ip6r0_len/2))
 1006                                                 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1);
 1007                                 }
 1008                                 eoff += rthlen;
 1009                                 nxt = rth->ip6r_nxt;
 1010                                 break;
 1011                         case IPPROTO_FRAGMENT:
 1012 #ifndef PULLDOWN_TEST
 1013                                 IP6_EXTHDR_CHECK(m, 0, eoff +
 1014                                     sizeof(struct ip6_frag), -1);
 1015                                 fh = (struct ip6_frag *)(mtod(m, caddr_t) +
 1016                                     eoff);
 1017 #else
 1018                                 IP6_EXTHDR_GET(fh, struct ip6_frag *, m,
 1019                                     eoff, sizeof(*fh));
 1020                                 if (fh == NULL) {
 1021                                         ICMP6STAT_INC(icp6s_tooshort);
 1022                                         return (-1);
 1023                                 }
 1024 #endif
 1025                                 /*
 1026                                  * Data after a fragment header is meaningless
 1027                                  * unless it is the first fragment, but
 1028                                  * we'll go to the notify label for path MTU
 1029                                  * discovery.
 1030                                  */
 1031                                 if (fh->ip6f_offlg & IP6F_OFF_MASK)
 1032                                         goto notify;
 1033 
 1034                                 eoff += sizeof(struct ip6_frag);
 1035                                 nxt = fh->ip6f_nxt;
 1036                                 break;
 1037                         default:
 1038                                 /*
 1039                                  * This case includes ESP and the No Next
 1040                                  * Header.  In such cases going to the notify
 1041                                  * label does not have any meaning
 1042                                  * (i.e. ctlfunc will be NULL), but we go
 1043                                  * anyway since we might have to update
 1044                                  * path MTU information.
 1045                                  */
 1046                                 goto notify;
 1047                         }
 1048                 }
 1049           notify:
 1050 #ifndef PULLDOWN_TEST
 1051                 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
 1052 #else
 1053                 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
 1054                     sizeof(*icmp6) + sizeof(struct ip6_hdr));
 1055                 if (icmp6 == NULL) {
 1056                         ICMP6STAT_INC(icp6s_tooshort);
 1057                         return (-1);
 1058                 }
 1059 #endif
 1060 
 1061                 /*
 1062                  * retrieve parameters from the inner IPv6 header, and convert
 1063                  * them into sockaddr structures.
 1064                  * XXX: there is no guarantee that the source or destination
 1065                  * addresses of the inner packet are in the same scope as
 1066                  * the addresses of the icmp packet.  But there is no other
 1067                  * way to determine the zone.
 1068                  */
 1069                 eip6 = (struct ip6_hdr *)(icmp6 + 1);
 1070 
 1071                 bzero(&icmp6dst, sizeof(icmp6dst));
 1072                 icmp6dst.sin6_len = sizeof(struct sockaddr_in6);
 1073                 icmp6dst.sin6_family = AF_INET6;
 1074                 if (finaldst == NULL)
 1075                         icmp6dst.sin6_addr = eip6->ip6_dst;
 1076                 else
 1077                         icmp6dst.sin6_addr = *finaldst;
 1078                 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL))
 1079                         goto freeit;
 1080                 bzero(&icmp6src, sizeof(icmp6src));
 1081                 icmp6src.sin6_len = sizeof(struct sockaddr_in6);
 1082                 icmp6src.sin6_family = AF_INET6;
 1083                 icmp6src.sin6_addr = eip6->ip6_src;
 1084                 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL))
 1085                         goto freeit;
 1086                 icmp6src.sin6_flowinfo =
 1087                     (eip6->ip6_flow & IPV6_FLOWLABEL_MASK);
 1088 
 1089                 if (finaldst == NULL)
 1090                         finaldst = &eip6->ip6_dst;
 1091                 ip6cp.ip6c_m = m;
 1092                 ip6cp.ip6c_icmp6 = icmp6;
 1093                 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
 1094                 ip6cp.ip6c_off = eoff;
 1095                 ip6cp.ip6c_finaldst = finaldst;
 1096                 ip6cp.ip6c_src = &icmp6src;
 1097                 ip6cp.ip6c_nxt = nxt;
 1098 
 1099                 if (icmp6type == ICMP6_PACKET_TOO_BIG) {
 1100                         notifymtu = ntohl(icmp6->icmp6_mtu);
 1101                         ip6cp.ip6c_cmdarg = (void *)&notifymtu;
 1102                         icmp6_mtudisc_update(&ip6cp, 1);        /*XXX*/
 1103                 }
 1104 
 1105                 ctlfunc = (void (*)(int, struct sockaddr *, void *))
 1106                     (inet6sw[ip6_protox[nxt]].pr_ctlinput);
 1107                 if (ctlfunc) {
 1108                         (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst,
 1109                             &ip6cp);
 1110                 }
 1111         }
 1112         *mp = m;
 1113         return (0);
 1114 
 1115   freeit:
 1116         m_freem(m);
 1117         return (-1);
 1118 }
 1119 
 1120 void
 1121 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated)
 1122 {
 1123         struct in6_addr *dst = ip6cp->ip6c_finaldst;
 1124         struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6;
 1125         struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */
 1126         u_int mtu = ntohl(icmp6->icmp6_mtu);
 1127         struct in_conninfo inc;
 1128 
 1129 #if 0
 1130         /*
 1131          * RFC2460 section 5, last paragraph.
 1132          * even though minimum link MTU for IPv6 is IPV6_MMTU,
 1133          * we may see ICMPv6 too big with mtu < IPV6_MMTU
 1134          * due to packet translator in the middle.
 1135          * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for
 1136          * special handling.
 1137          */
 1138         if (mtu < IPV6_MMTU)
 1139                 return;
 1140 #endif
 1141 
 1142         /*
 1143          * we reject ICMPv6 too big with abnormally small value.
 1144          * XXX what is the good definition of "abnormally small"?
 1145          */
 1146         if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8)
 1147                 return;
 1148 
 1149         if (!validated)
 1150                 return;
 1151 
 1152         /*
 1153          * In case the suggested mtu is less than IPV6_MMTU, we
 1154          * only need to remember that it was for above mentioned
 1155          * "alwaysfrag" case.
 1156          * Try to be as close to the spec as possible.
 1157          */
 1158         if (mtu < IPV6_MMTU)
 1159                 mtu = IPV6_MMTU - 8;
 1160 
 1161         bzero(&inc, sizeof(inc));
 1162         inc.inc_flags |= INC_ISIPV6;
 1163         inc.inc6_faddr = *dst;
 1164         if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL))
 1165                 return;
 1166 
 1167         if (mtu < tcp_maxmtu6(&inc, NULL)) {
 1168                 tcp_hc_updatemtu(&inc, mtu);
 1169                 ICMP6STAT_INC(icp6s_pmtuchg);
 1170         }
 1171 }
 1172 
 1173 /*
 1174  * Process a Node Information Query packet, based on
 1175  * draft-ietf-ipngwg-icmp-name-lookups-07.
 1176  *
 1177  * Spec incompatibilities:
 1178  * - IPv6 Subject address handling
 1179  * - IPv4 Subject address handling support missing
 1180  * - Proxy reply (answer even if it's not for me)
 1181  * - joins NI group address at in6_ifattach() time only, does not cope
 1182  *   with hostname changes by sethostname(3)
 1183  */
 1184 static struct mbuf *
 1185 ni6_input(struct mbuf *m, int off)
 1186 {
 1187         struct icmp6_nodeinfo *ni6, *nni6;
 1188         struct mbuf *n = NULL;
 1189         struct prison *pr;
 1190         u_int16_t qtype;
 1191         int subjlen;
 1192         int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
 1193         struct ni_reply_fqdn *fqdn;
 1194         int addrs;              /* for NI_QTYPE_NODEADDR */
 1195         struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
 1196         struct in6_addr in6_subj; /* subject address */
 1197         struct ip6_hdr *ip6;
 1198         int oldfqdn = 0;        /* if 1, return pascal string (03 draft) */
 1199         char *subj = NULL;
 1200         struct in6_ifaddr *ia6 = NULL;
 1201 
 1202         ip6 = mtod(m, struct ip6_hdr *);
 1203 #ifndef PULLDOWN_TEST
 1204         ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
 1205 #else
 1206         IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
 1207         if (ni6 == NULL) {
 1208                 /* m is already reclaimed */
 1209                 return (NULL);
 1210         }
 1211 #endif
 1212 
 1213         /*
 1214          * Validate IPv6 source address.
 1215          * The default configuration MUST be to refuse answering queries from
 1216          * global-scope addresses according to RFC4602.
 1217          * Notes:
 1218          *  - it's not very clear what "refuse" means; this implementation
 1219          *    simply drops it.
 1220          *  - it's not very easy to identify global-scope (unicast) addresses
 1221          *    since there are many prefixes for them.  It should be safer
 1222          *    and in practice sufficient to check "all" but loopback and
 1223          *    link-local (note that site-local unicast was deprecated and
 1224          *    ULA is defined as global scope-wise)
 1225          */
 1226         if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_GLOBALOK) == 0 &&
 1227             !IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) &&
 1228             !IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src))
 1229                 goto bad;
 1230 
 1231         /*
 1232          * Validate IPv6 destination address.
 1233          *
 1234          * The Responder must discard the Query without further processing
 1235          * unless it is one of the Responder's unicast or anycast addresses, or
 1236          * a link-local scope multicast address which the Responder has joined.
 1237          * [RFC4602, Section 5.]
 1238          */
 1239         if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
 1240                 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst))
 1241                         goto bad;
 1242                 /* else it's a link-local multicast, fine */
 1243         } else {                /* unicast or anycast */
 1244                 if ((ia6 = ip6_getdstifaddr(m)) == NULL)
 1245                         goto bad; /* XXX impossible */
 1246 
 1247                 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) &&
 1248                     !(V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK)) {
 1249                         ifa_free(&ia6->ia_ifa);
 1250                         nd6log((LOG_DEBUG, "ni6_input: ignore node info to "
 1251                                 "a temporary address in %s:%d",
 1252                                __FILE__, __LINE__));
 1253                         goto bad;
 1254                 }
 1255                 ifa_free(&ia6->ia_ifa);
 1256         }
 1257 
 1258         /* validate query Subject field. */
 1259         qtype = ntohs(ni6->ni_qtype);
 1260         subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
 1261         switch (qtype) {
 1262         case NI_QTYPE_NOOP:
 1263         case NI_QTYPE_SUPTYPES:
 1264                 /* 07 draft */
 1265                 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0)
 1266                         break;
 1267                 /* FALLTHROUGH */
 1268         case NI_QTYPE_FQDN:
 1269         case NI_QTYPE_NODEADDR:
 1270         case NI_QTYPE_IPV4ADDR:
 1271                 switch (ni6->ni_code) {
 1272                 case ICMP6_NI_SUBJ_IPV6:
 1273 #if ICMP6_NI_SUBJ_IPV6 != 0
 1274                 case 0:
 1275 #endif
 1276                         /*
 1277                          * backward compatibility - try to accept 03 draft
 1278                          * format, where no Subject is present.
 1279                          */
 1280                         if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 &&
 1281                             subjlen == 0) {
 1282                                 oldfqdn++;
 1283                                 break;
 1284                         }
 1285 #if ICMP6_NI_SUBJ_IPV6 != 0
 1286                         if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6)
 1287                                 goto bad;
 1288 #endif
 1289 
 1290                         if (subjlen != sizeof(struct in6_addr))
 1291                                 goto bad;
 1292 
 1293                         /*
 1294                          * Validate Subject address.
 1295                          *
 1296                          * Not sure what exactly "address belongs to the node"
 1297                          * means in the spec, is it just unicast, or what?
 1298                          *
 1299                          * At this moment we consider Subject address as
 1300                          * "belong to the node" if the Subject address equals
 1301                          * to the IPv6 destination address; validation for
 1302                          * IPv6 destination address should have done enough
 1303                          * check for us.
 1304                          *
 1305                          * We do not do proxy at this moment.
 1306                          */
 1307                         /* m_pulldown instead of copy? */
 1308                         m_copydata(m, off + sizeof(struct icmp6_nodeinfo),
 1309                             subjlen, (caddr_t)&in6_subj);
 1310                         if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL))
 1311                                 goto bad;
 1312 
 1313                         subj = (char *)&in6_subj;
 1314                         if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj))
 1315                                 break;
 1316 
 1317                         /*
 1318                          * XXX if we are to allow other cases, we should really
 1319                          * be careful about scope here.
 1320                          * basically, we should disallow queries toward IPv6
 1321                          * destination X with subject Y,
 1322                          * if scope(X) > scope(Y).
 1323                          * if we allow scope(X) > scope(Y), it will result in
 1324                          * information leakage across scope boundary.
 1325                          */
 1326                         goto bad;
 1327 
 1328                 case ICMP6_NI_SUBJ_FQDN:
 1329                         /*
 1330                          * Validate Subject name with gethostname(3).
 1331                          *
 1332                          * The behavior may need some debate, since:
 1333                          * - we are not sure if the node has FQDN as
 1334                          *   hostname (returned by gethostname(3)).
 1335                          * - the code does wildcard match for truncated names.
 1336                          *   however, we are not sure if we want to perform
 1337                          *   wildcard match, if gethostname(3) side has
 1338                          *   truncated hostname.
 1339                          */
 1340                         pr = curthread->td_ucred->cr_prison;
 1341                         mtx_lock(&pr->pr_mtx);
 1342                         n = ni6_nametodns(pr->pr_hostname,
 1343                             strlen(pr->pr_hostname), 0);
 1344                         mtx_unlock(&pr->pr_mtx);
 1345                         if (!n || n->m_next || n->m_len == 0)
 1346                                 goto bad;
 1347                         IP6_EXTHDR_GET(subj, char *, m,
 1348                             off + sizeof(struct icmp6_nodeinfo), subjlen);
 1349                         if (subj == NULL)
 1350                                 goto bad;
 1351                         if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *),
 1352                             n->m_len)) {
 1353                                 goto bad;
 1354                         }
 1355                         m_freem(n);
 1356                         n = NULL;
 1357                         break;
 1358 
 1359                 case ICMP6_NI_SUBJ_IPV4:        /* XXX: to be implemented? */
 1360                 default:
 1361                         goto bad;
 1362                 }
 1363                 break;
 1364         }
 1365 
 1366         /* refuse based on configuration.  XXX ICMP6_NI_REFUSED? */
 1367         switch (qtype) {
 1368         case NI_QTYPE_FQDN:
 1369                 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_FQDNOK) == 0)
 1370                         goto bad;
 1371                 break;
 1372         case NI_QTYPE_NODEADDR:
 1373         case NI_QTYPE_IPV4ADDR:
 1374                 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_NODEADDROK) == 0)
 1375                         goto bad;
 1376                 break;
 1377         }
 1378 
 1379         /* guess reply length */
 1380         switch (qtype) {
 1381         case NI_QTYPE_NOOP:
 1382                 break;          /* no reply data */
 1383         case NI_QTYPE_SUPTYPES:
 1384                 replylen += sizeof(u_int32_t);
 1385                 break;
 1386         case NI_QTYPE_FQDN:
 1387                 /* XXX will append an mbuf */
 1388                 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
 1389                 break;
 1390         case NI_QTYPE_NODEADDR:
 1391                 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj);
 1392                 if ((replylen += addrs * (sizeof(struct in6_addr) +
 1393                     sizeof(u_int32_t))) > MCLBYTES)
 1394                         replylen = MCLBYTES; /* XXX: will truncate pkt later */
 1395                 break;
 1396         case NI_QTYPE_IPV4ADDR:
 1397                 /* unsupported - should respond with unknown Qtype? */
 1398                 break;
 1399         default:
 1400                 /*
 1401                  * XXX: We must return a reply with the ICMP6 code
 1402                  * `unknown Qtype' in this case.  However we regard the case
 1403                  * as an FQDN query for backward compatibility.
 1404                  * Older versions set a random value to this field,
 1405                  * so it rarely varies in the defined qtypes.
 1406                  * But the mechanism is not reliable...
 1407                  * maybe we should obsolete older versions.
 1408                  */
 1409                 qtype = NI_QTYPE_FQDN;
 1410                 /* XXX will append an mbuf */
 1411                 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
 1412                 oldfqdn++;
 1413                 break;
 1414         }
 1415 
 1416         /* allocate an mbuf to reply. */
 1417         MGETHDR(n, M_DONTWAIT, m->m_type);
 1418         if (n == NULL) {
 1419                 m_freem(m);
 1420                 return (NULL);
 1421         }
 1422         M_MOVE_PKTHDR(n, m); /* just for recvif */
 1423         if (replylen > MHLEN) {
 1424                 if (replylen > MCLBYTES) {
 1425                         /*
 1426                          * XXX: should we try to allocate more? But MCLBYTES
 1427                          * is probably much larger than IPV6_MMTU...
 1428                          */
 1429                         goto bad;
 1430                 }
 1431                 MCLGET(n, M_DONTWAIT);
 1432                 if ((n->m_flags & M_EXT) == 0) {
 1433                         goto bad;
 1434                 }
 1435         }
 1436         n->m_pkthdr.len = n->m_len = replylen;
 1437 
 1438         /* copy mbuf header and IPv6 + Node Information base headers */
 1439         bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
 1440         nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
 1441         bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
 1442 
 1443         /* qtype dependent procedure */
 1444         switch (qtype) {
 1445         case NI_QTYPE_NOOP:
 1446                 nni6->ni_code = ICMP6_NI_SUCCESS;
 1447                 nni6->ni_flags = 0;
 1448                 break;
 1449         case NI_QTYPE_SUPTYPES:
 1450         {
 1451                 u_int32_t v;
 1452                 nni6->ni_code = ICMP6_NI_SUCCESS;
 1453                 nni6->ni_flags = htons(0x0000); /* raw bitmap */
 1454                 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */
 1455                 v = (u_int32_t)htonl(0x0000000f);
 1456                 bcopy(&v, nni6 + 1, sizeof(u_int32_t));
 1457                 break;
 1458         }
 1459         case NI_QTYPE_FQDN:
 1460                 nni6->ni_code = ICMP6_NI_SUCCESS;
 1461                 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
 1462                     sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo));
 1463                 nni6->ni_flags = 0; /* XXX: meaningless TTL */
 1464                 fqdn->ni_fqdn_ttl = 0;  /* ditto. */
 1465                 /*
 1466                  * XXX do we really have FQDN in hostname?
 1467                  */
 1468                 pr = curthread->td_ucred->cr_prison;
 1469                 mtx_lock(&pr->pr_mtx);
 1470                 n->m_next = ni6_nametodns(pr->pr_hostname,
 1471                     strlen(pr->pr_hostname), oldfqdn);
 1472                 mtx_unlock(&pr->pr_mtx);
 1473                 if (n->m_next == NULL)
 1474                         goto bad;
 1475                 /* XXX we assume that n->m_next is not a chain */
 1476                 if (n->m_next->m_next != NULL)
 1477                         goto bad;
 1478                 n->m_pkthdr.len += n->m_next->m_len;
 1479                 break;
 1480         case NI_QTYPE_NODEADDR:
 1481         {
 1482                 int lenlim, copied;
 1483 
 1484                 nni6->ni_code = ICMP6_NI_SUCCESS;
 1485                 n->m_pkthdr.len = n->m_len =
 1486                     sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
 1487                 lenlim = M_TRAILINGSPACE(n);
 1488                 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
 1489                 /* XXX: reset mbuf length */
 1490                 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
 1491                     sizeof(struct icmp6_nodeinfo) + copied;
 1492                 break;
 1493         }
 1494         default:
 1495                 break;          /* XXX impossible! */
 1496         }
 1497 
 1498         nni6->ni_type = ICMP6_NI_REPLY;
 1499         m_freem(m);
 1500         return (n);
 1501 
 1502   bad:
 1503         m_freem(m);
 1504         if (n)
 1505                 m_freem(n);
 1506         return (NULL);
 1507 }
 1508 
 1509 /*
 1510  * make a mbuf with DNS-encoded string.  no compression support.
 1511  *
 1512  * XXX names with less than 2 dots (like "foo" or "foo.section") will be
 1513  * treated as truncated name (two \0 at the end).  this is a wild guess.
 1514  *
 1515  * old - return pascal string if non-zero
 1516  */
 1517 static struct mbuf *
 1518 ni6_nametodns(const char *name, int namelen, int old)
 1519 {
 1520         struct mbuf *m;
 1521         char *cp, *ep;
 1522         const char *p, *q;
 1523         int i, len, nterm;
 1524 
 1525         if (old)
 1526                 len = namelen + 1;
 1527         else
 1528                 len = MCLBYTES;
 1529 
 1530         /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */
 1531         MGET(m, M_DONTWAIT, MT_DATA);
 1532         if (m && len > MLEN) {
 1533                 MCLGET(m, M_DONTWAIT);
 1534                 if ((m->m_flags & M_EXT) == 0)
 1535                         goto fail;
 1536         }
 1537         if (!m)
 1538                 goto fail;
 1539         m->m_next = NULL;
 1540 
 1541         if (old) {
 1542                 m->m_len = len;
 1543                 *mtod(m, char *) = namelen;
 1544                 bcopy(name, mtod(m, char *) + 1, namelen);
 1545                 return m;
 1546         } else {
 1547                 m->m_len = 0;
 1548                 cp = mtod(m, char *);
 1549                 ep = mtod(m, char *) + M_TRAILINGSPACE(m);
 1550 
 1551                 /* if not certain about my name, return empty buffer */
 1552                 if (namelen == 0)
 1553                         return m;
 1554 
 1555                 /*
 1556                  * guess if it looks like shortened hostname, or FQDN.
 1557                  * shortened hostname needs two trailing "\0".
 1558                  */
 1559                 i = 0;
 1560                 for (p = name; p < name + namelen; p++) {
 1561                         if (*p && *p == '.')
 1562                                 i++;
 1563                 }
 1564                 if (i < 2)
 1565                         nterm = 2;
 1566                 else
 1567                         nterm = 1;
 1568 
 1569                 p = name;
 1570                 while (cp < ep && p < name + namelen) {
 1571                         i = 0;
 1572                         for (q = p; q < name + namelen && *q && *q != '.'; q++)
 1573                                 i++;
 1574                         /* result does not fit into mbuf */
 1575                         if (cp + i + 1 >= ep)
 1576                                 goto fail;
 1577                         /*
 1578                          * DNS label length restriction, RFC1035 page 8.
 1579                          * "i == 0" case is included here to avoid returning
 1580                          * 0-length label on "foo..bar".
 1581                          */
 1582                         if (i <= 0 || i >= 64)
 1583                                 goto fail;
 1584                         *cp++ = i;
 1585                         bcopy(p, cp, i);
 1586                         cp += i;
 1587                         p = q;
 1588                         if (p < name + namelen && *p == '.')
 1589                                 p++;
 1590                 }
 1591                 /* termination */
 1592                 if (cp + nterm >= ep)
 1593                         goto fail;
 1594                 while (nterm-- > 0)
 1595                         *cp++ = '\0';
 1596                 m->m_len = cp - mtod(m, char *);
 1597                 return m;
 1598         }
 1599 
 1600         panic("should not reach here");
 1601         /* NOTREACHED */
 1602 
 1603  fail:
 1604         if (m)
 1605                 m_freem(m);
 1606         return NULL;
 1607 }
 1608 
 1609 /*
 1610  * check if two DNS-encoded string matches.  takes care of truncated
 1611  * form (with \0\0 at the end).  no compression support.
 1612  * XXX upper/lowercase match (see RFC2065)
 1613  */
 1614 static int
 1615 ni6_dnsmatch(const char *a, int alen, const char *b, int blen)
 1616 {
 1617         const char *a0, *b0;
 1618         int l;
 1619 
 1620         /* simplest case - need validation? */
 1621         if (alen == blen && bcmp(a, b, alen) == 0)
 1622                 return 1;
 1623 
 1624         a0 = a;
 1625         b0 = b;
 1626 
 1627         /* termination is mandatory */
 1628         if (alen < 2 || blen < 2)
 1629                 return 0;
 1630         if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0')
 1631                 return 0;
 1632         alen--;
 1633         blen--;
 1634 
 1635         while (a - a0 < alen && b - b0 < blen) {
 1636                 if (a - a0 + 1 > alen || b - b0 + 1 > blen)
 1637                         return 0;
 1638 
 1639                 if ((signed char)a[0] < 0 || (signed char)b[0] < 0)
 1640                         return 0;
 1641                 /* we don't support compression yet */
 1642                 if (a[0] >= 64 || b[0] >= 64)
 1643                         return 0;
 1644 
 1645                 /* truncated case */
 1646                 if (a[0] == 0 && a - a0 == alen - 1)
 1647                         return 1;
 1648                 if (b[0] == 0 && b - b0 == blen - 1)
 1649                         return 1;
 1650                 if (a[0] == 0 || b[0] == 0)
 1651                         return 0;
 1652 
 1653                 if (a[0] != b[0])
 1654                         return 0;
 1655                 l = a[0];
 1656                 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen)
 1657                         return 0;
 1658                 if (bcmp(a + 1, b + 1, l) != 0)
 1659                         return 0;
 1660 
 1661                 a += 1 + l;
 1662                 b += 1 + l;
 1663         }
 1664 
 1665         if (a - a0 == alen && b - b0 == blen)
 1666                 return 1;
 1667         else
 1668                 return 0;
 1669 }
 1670 
 1671 /*
 1672  * calculate the number of addresses to be returned in the node info reply.
 1673  */
 1674 static int
 1675 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp,
 1676     struct in6_addr *subj)
 1677 {
 1678         struct ifnet *ifp;
 1679         struct in6_ifaddr *ifa6;
 1680         struct ifaddr *ifa;
 1681         int addrs = 0, addrsofif, iffound = 0;
 1682         int niflags = ni6->ni_flags;
 1683 
 1684         if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) {
 1685                 switch (ni6->ni_code) {
 1686                 case ICMP6_NI_SUBJ_IPV6:
 1687                         if (subj == NULL) /* must be impossible... */
 1688                                 return (0);
 1689                         break;
 1690                 default:
 1691                         /*
 1692                          * XXX: we only support IPv6 subject address for
 1693                          * this Qtype.
 1694                          */
 1695                         return (0);
 1696                 }
 1697         }
 1698 
 1699         IFNET_RLOCK_NOSLEEP();
 1700         for (ifp = TAILQ_FIRST(&V_ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
 1701                 addrsofif = 0;
 1702                 IF_ADDR_LOCK(ifp);
 1703                 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 1704                         if (ifa->ifa_addr->sa_family != AF_INET6)
 1705                                 continue;
 1706                         ifa6 = (struct in6_ifaddr *)ifa;
 1707 
 1708                         if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 &&
 1709                             IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr))
 1710                                 iffound = 1;
 1711 
 1712                         /*
 1713                          * IPv4-mapped addresses can only be returned by a
 1714                          * Node Information proxy, since they represent
 1715                          * addresses of IPv4-only nodes, which perforce do
 1716                          * not implement this protocol.
 1717                          * [icmp-name-lookups-07, Section 5.4]
 1718                          * So we don't support NI_NODEADDR_FLAG_COMPAT in
 1719                          * this function at this moment.
 1720                          */
 1721 
 1722                         /* What do we have to do about ::1? */
 1723                         switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
 1724                         case IPV6_ADDR_SCOPE_LINKLOCAL:
 1725                                 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
 1726                                         continue;
 1727                                 break;
 1728                         case IPV6_ADDR_SCOPE_SITELOCAL:
 1729                                 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
 1730                                         continue;
 1731                                 break;
 1732                         case IPV6_ADDR_SCOPE_GLOBAL:
 1733                                 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
 1734                                         continue;
 1735                                 break;
 1736                         default:
 1737                                 continue;
 1738                         }
 1739 
 1740                         /*
 1741                          * check if anycast is okay.
 1742                          * XXX: just experimental.  not in the spec.
 1743                          */
 1744                         if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
 1745                             (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
 1746                                 continue; /* we need only unicast addresses */
 1747                         if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
 1748                             (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) {
 1749                                 continue;
 1750                         }
 1751                         addrsofif++; /* count the address */
 1752                 }
 1753                 IF_ADDR_UNLOCK(ifp);
 1754                 if (iffound) {
 1755                         *ifpp = ifp;
 1756                         IFNET_RUNLOCK_NOSLEEP();
 1757                         return (addrsofif);
 1758                 }
 1759 
 1760                 addrs += addrsofif;
 1761         }
 1762         IFNET_RUNLOCK_NOSLEEP();
 1763 
 1764         return (addrs);
 1765 }
 1766 
 1767 static int
 1768 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6,
 1769     struct ifnet *ifp0, int resid)
 1770 {
 1771         struct ifnet *ifp;
 1772         struct in6_ifaddr *ifa6;
 1773         struct ifaddr *ifa;
 1774         struct ifnet *ifp_dep = NULL;
 1775         int copied = 0, allow_deprecated = 0;
 1776         u_char *cp = (u_char *)(nni6 + 1);
 1777         int niflags = ni6->ni_flags;
 1778         u_int32_t ltime;
 1779 
 1780         if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL))
 1781                 return (0);     /* needless to copy */
 1782 
 1783         IFNET_RLOCK_NOSLEEP();
 1784         ifp = ifp0 ? ifp0 : TAILQ_FIRST(&V_ifnet);
 1785   again:
 1786 
 1787         for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
 1788                 IF_ADDR_LOCK(ifp);
 1789                 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 1790                         if (ifa->ifa_addr->sa_family != AF_INET6)
 1791                                 continue;
 1792                         ifa6 = (struct in6_ifaddr *)ifa;
 1793 
 1794                         if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 &&
 1795                             allow_deprecated == 0) {
 1796                                 /*
 1797                                  * prefererred address should be put before
 1798                                  * deprecated addresses.
 1799                                  */
 1800 
 1801                                 /* record the interface for later search */
 1802                                 if (ifp_dep == NULL)
 1803                                         ifp_dep = ifp;
 1804 
 1805                                 continue;
 1806                         } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 &&
 1807                             allow_deprecated != 0)
 1808                                 continue; /* we now collect deprecated addrs */
 1809 
 1810                         /* What do we have to do about ::1? */
 1811                         switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
 1812                         case IPV6_ADDR_SCOPE_LINKLOCAL:
 1813                                 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
 1814                                         continue;
 1815                                 break;
 1816                         case IPV6_ADDR_SCOPE_SITELOCAL:
 1817                                 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
 1818                                         continue;
 1819                                 break;
 1820                         case IPV6_ADDR_SCOPE_GLOBAL:
 1821                                 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
 1822                                         continue;
 1823                                 break;
 1824                         default:
 1825                                 continue;
 1826                         }
 1827 
 1828                         /*
 1829                          * check if anycast is okay.
 1830                          * XXX: just experimental.  not in the spec.
 1831                          */
 1832                         if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
 1833                             (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
 1834                                 continue;
 1835                         if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
 1836                             (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) {
 1837                                 continue;
 1838                         }
 1839 
 1840                         /* now we can copy the address */
 1841                         if (resid < sizeof(struct in6_addr) +
 1842                             sizeof(u_int32_t)) {
 1843                                 IF_ADDR_UNLOCK(ifp);
 1844                                 /*
 1845                                  * We give up much more copy.
 1846                                  * Set the truncate flag and return.
 1847                                  */
 1848                                 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE;
 1849                                 IFNET_RUNLOCK_NOSLEEP();
 1850                                 return (copied);
 1851                         }
 1852 
 1853                         /*
 1854                          * Set the TTL of the address.
 1855                          * The TTL value should be one of the following
 1856                          * according to the specification:
 1857                          *
 1858                          * 1. The remaining lifetime of a DHCP lease on the
 1859                          *    address, or
 1860                          * 2. The remaining Valid Lifetime of a prefix from
 1861                          *    which the address was derived through Stateless
 1862                          *    Autoconfiguration.
 1863                          *
 1864                          * Note that we currently do not support stateful
 1865                          * address configuration by DHCPv6, so the former
 1866                          * case can't happen.
 1867                          */
 1868                         if (ifa6->ia6_lifetime.ia6t_expire == 0)
 1869                                 ltime = ND6_INFINITE_LIFETIME;
 1870                         else {
 1871                                 if (ifa6->ia6_lifetime.ia6t_expire >
 1872                                     time_second)
 1873                                         ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second);
 1874                                 else
 1875                                         ltime = 0;
 1876                         }
 1877 
 1878                         bcopy(&ltime, cp, sizeof(u_int32_t));
 1879                         cp += sizeof(u_int32_t);
 1880 
 1881                         /* copy the address itself */
 1882                         bcopy(&ifa6->ia_addr.sin6_addr, cp,
 1883                             sizeof(struct in6_addr));
 1884                         in6_clearscope((struct in6_addr *)cp); /* XXX */
 1885                         cp += sizeof(struct in6_addr);
 1886 
 1887                         resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t));
 1888                         copied += (sizeof(struct in6_addr) + sizeof(u_int32_t));
 1889                 }
 1890                 IF_ADDR_UNLOCK(ifp);
 1891                 if (ifp0)       /* we need search only on the specified IF */
 1892                         break;
 1893         }
 1894 
 1895         if (allow_deprecated == 0 && ifp_dep != NULL) {
 1896                 ifp = ifp_dep;
 1897                 allow_deprecated = 1;
 1898 
 1899                 goto again;
 1900         }
 1901 
 1902         IFNET_RUNLOCK_NOSLEEP();
 1903 
 1904         return (copied);
 1905 }
 1906 
 1907 /*
 1908  * XXX almost dup'ed code with rip6_input.
 1909  */
 1910 static int
 1911 icmp6_rip6_input(struct mbuf **mp, int off)
 1912 {
 1913         struct mbuf *m = *mp;
 1914         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
 1915         struct inpcb *in6p;
 1916         struct inpcb *last = NULL;
 1917         struct sockaddr_in6 fromsa;
 1918         struct icmp6_hdr *icmp6;
 1919         struct mbuf *opts = NULL;
 1920 
 1921 #ifndef PULLDOWN_TEST
 1922         /* this is assumed to be safe. */
 1923         icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
 1924 #else
 1925         IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
 1926         if (icmp6 == NULL) {
 1927                 /* m is already reclaimed */
 1928                 return (IPPROTO_DONE);
 1929         }
 1930 #endif
 1931 
 1932         /*
 1933          * XXX: the address may have embedded scope zone ID, which should be
 1934          * hidden from applications.
 1935          */
 1936         bzero(&fromsa, sizeof(fromsa));
 1937         fromsa.sin6_family = AF_INET6;
 1938         fromsa.sin6_len = sizeof(struct sockaddr_in6);
 1939         fromsa.sin6_addr = ip6->ip6_src;
 1940         if (sa6_recoverscope(&fromsa)) {
 1941                 m_freem(m);
 1942                 return (IPPROTO_DONE);
 1943         }
 1944 
 1945         INP_INFO_RLOCK(&V_ripcbinfo);
 1946         LIST_FOREACH(in6p, &V_ripcb, inp_list) {
 1947                 if ((in6p->inp_vflag & INP_IPV6) == 0)
 1948                         continue;
 1949                 if (in6p->inp_ip_p != IPPROTO_ICMPV6)
 1950                         continue;
 1951                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
 1952                    !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
 1953                         continue;
 1954                 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
 1955                    !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
 1956                         continue;
 1957                 INP_RLOCK(in6p);
 1958                 if (ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
 1959                     in6p->in6p_icmp6filt)) {
 1960                         INP_RUNLOCK(in6p);
 1961                         continue;
 1962                 }
 1963                 if (last != NULL) {
 1964                         struct  mbuf *n = NULL;
 1965 
 1966                         /*
 1967                          * Recent network drivers tend to allocate a single
 1968                          * mbuf cluster, rather than to make a couple of
 1969                          * mbufs without clusters.  Also, since the IPv6 code
 1970                          * path tries to avoid m_pullup(), it is highly
 1971                          * probable that we still have an mbuf cluster here
 1972                          * even though the necessary length can be stored in an
 1973                          * mbuf's internal buffer.
 1974                          * Meanwhile, the default size of the receive socket
 1975                          * buffer for raw sockets is not so large.  This means
 1976                          * the possibility of packet loss is relatively higher
 1977                          * than before.  To avoid this scenario, we copy the
 1978                          * received data to a separate mbuf that does not use
 1979                          * a cluster, if possible.
 1980                          * XXX: it is better to copy the data after stripping
 1981                          * intermediate headers.
 1982                          */
 1983                         if ((m->m_flags & M_EXT) && m->m_next == NULL &&
 1984                             m->m_len <= MHLEN) {
 1985                                 MGET(n, M_DONTWAIT, m->m_type);
 1986                                 if (n != NULL) {
 1987                                         if (m_dup_pkthdr(n, m, M_NOWAIT)) {
 1988                                                 bcopy(m->m_data, n->m_data,
 1989                                                       m->m_len);
 1990                                                 n->m_len = m->m_len;
 1991                                         } else {
 1992                                                 m_free(n);
 1993                                                 n = NULL;
 1994                                         }
 1995                                 }
 1996                         }
 1997                         if (n != NULL ||
 1998                             (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
 1999                                 if (last->inp_flags & INP_CONTROLOPTS)
 2000                                         ip6_savecontrol(last, n, &opts);
 2001                                 /* strip intermediate headers */
 2002                                 m_adj(n, off);
 2003                                 SOCKBUF_LOCK(&last->inp_socket->so_rcv);
 2004                                 if (sbappendaddr_locked(
 2005                                     &last->inp_socket->so_rcv,
 2006                                     (struct sockaddr *)&fromsa, n, opts)
 2007                                     == 0) {
 2008                                         /* should notify about lost packet */
 2009                                         m_freem(n);
 2010                                         if (opts) {
 2011                                                 m_freem(opts);
 2012                                         }
 2013                                         SOCKBUF_UNLOCK(
 2014                                             &last->inp_socket->so_rcv);
 2015                                 } else
 2016                                         sorwakeup_locked(last->inp_socket);
 2017                                 opts = NULL;
 2018                         }
 2019                         INP_RUNLOCK(last);
 2020                 }
 2021                 last = in6p;
 2022         }
 2023         INP_INFO_RUNLOCK(&V_ripcbinfo);
 2024         if (last != NULL) {
 2025                 if (last->inp_flags & INP_CONTROLOPTS)
 2026                         ip6_savecontrol(last, m, &opts);
 2027                 /* strip intermediate headers */
 2028                 m_adj(m, off);
 2029 
 2030                 /* avoid using mbuf clusters if possible (see above) */
 2031                 if ((m->m_flags & M_EXT) && m->m_next == NULL &&
 2032                     m->m_len <= MHLEN) {
 2033                         struct mbuf *n;
 2034 
 2035                         MGET(n, M_DONTWAIT, m->m_type);
 2036                         if (n != NULL) {
 2037                                 if (m_dup_pkthdr(n, m, M_NOWAIT)) {
 2038                                         bcopy(m->m_data, n->m_data, m->m_len);
 2039                                         n->m_len = m->m_len;
 2040 
 2041                                         m_freem(m);
 2042                                         m = n;
 2043                                 } else {
 2044                                         m_freem(n);
 2045                                         n = NULL;
 2046                                 }
 2047                         }
 2048                 }
 2049                 SOCKBUF_LOCK(&last->inp_socket->so_rcv);
 2050                 if (sbappendaddr_locked(&last->inp_socket->so_rcv,
 2051                     (struct sockaddr *)&fromsa, m, opts) == 0) {
 2052                         m_freem(m);
 2053                         if (opts)
 2054                                 m_freem(opts);
 2055                         SOCKBUF_UNLOCK(&last->inp_socket->so_rcv);
 2056                 } else
 2057                         sorwakeup_locked(last->inp_socket);
 2058                 INP_RUNLOCK(last);
 2059         } else {
 2060                 m_freem(m);
 2061                 IP6STAT_DEC(ip6s_delivered);
 2062         }
 2063         return IPPROTO_DONE;
 2064 }
 2065 
 2066 /*
 2067  * Reflect the ip6 packet back to the source.
 2068  * OFF points to the icmp6 header, counted from the top of the mbuf.
 2069  */
 2070 void
 2071 icmp6_reflect(struct mbuf *m, size_t off)
 2072 {
 2073         struct ip6_hdr *ip6;
 2074         struct icmp6_hdr *icmp6;
 2075         struct in6_ifaddr *ia = NULL;
 2076         int plen;
 2077         int type, code;
 2078         struct ifnet *outif = NULL;
 2079         struct in6_addr origdst, src, *srcp = NULL;
 2080 
 2081         /* too short to reflect */
 2082         if (off < sizeof(struct ip6_hdr)) {
 2083                 nd6log((LOG_DEBUG,
 2084                     "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
 2085                     (u_long)off, (u_long)sizeof(struct ip6_hdr),
 2086                     __FILE__, __LINE__));
 2087                 goto bad;
 2088         }
 2089 
 2090         /*
 2091          * If there are extra headers between IPv6 and ICMPv6, strip
 2092          * off that header first.
 2093          */
 2094 #ifdef DIAGNOSTIC
 2095         if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN)
 2096                 panic("assumption failed in icmp6_reflect");
 2097 #endif
 2098         if (off > sizeof(struct ip6_hdr)) {
 2099                 size_t l;
 2100                 struct ip6_hdr nip6;
 2101 
 2102                 l = off - sizeof(struct ip6_hdr);
 2103                 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
 2104                 m_adj(m, l);
 2105                 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
 2106                 if (m->m_len < l) {
 2107                         if ((m = m_pullup(m, l)) == NULL)
 2108                                 return;
 2109                 }
 2110                 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
 2111         } else /* off == sizeof(struct ip6_hdr) */ {
 2112                 size_t l;
 2113                 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
 2114                 if (m->m_len < l) {
 2115                         if ((m = m_pullup(m, l)) == NULL)
 2116                                 return;
 2117                 }
 2118         }
 2119         plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
 2120         ip6 = mtod(m, struct ip6_hdr *);
 2121         ip6->ip6_nxt = IPPROTO_ICMPV6;
 2122         icmp6 = (struct icmp6_hdr *)(ip6 + 1);
 2123         type = icmp6->icmp6_type; /* keep type for statistics */
 2124         code = icmp6->icmp6_code; /* ditto. */
 2125 
 2126         origdst = ip6->ip6_dst;
 2127         /*
 2128          * ip6_input() drops a packet if its src is multicast.
 2129          * So, the src is never multicast.
 2130          */
 2131         ip6->ip6_dst = ip6->ip6_src;
 2132 
 2133         /*
 2134          * If the incoming packet was addressed directly to us (i.e. unicast),
 2135          * use dst as the src for the reply.
 2136          * The IN6_IFF_NOTREADY case should be VERY rare, but is possible
 2137          * (for example) when we encounter an error while forwarding procedure
 2138          * destined to a duplicated address of ours.
 2139          * Note that ip6_getdstifaddr() may fail if we are in an error handling
 2140          * procedure of an outgoing packet of our own, in which case we need
 2141          * to search in the ifaddr list.
 2142          */
 2143         if (!IN6_IS_ADDR_MULTICAST(&origdst)) {
 2144                 if ((ia = ip6_getdstifaddr(m))) {
 2145                         if (!(ia->ia6_flags &
 2146                             (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)))
 2147                                 srcp = &ia->ia_addr.sin6_addr;
 2148                 } else {
 2149                         struct sockaddr_in6 d;
 2150 
 2151                         bzero(&d, sizeof(d));
 2152                         d.sin6_family = AF_INET6;
 2153                         d.sin6_len = sizeof(d);
 2154                         d.sin6_addr = origdst;
 2155                         ia = (struct in6_ifaddr *)
 2156                             ifa_ifwithaddr((struct sockaddr *)&d);
 2157                         if (ia &&
 2158                             !(ia->ia6_flags &
 2159                             (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) {
 2160                                 srcp = &ia->ia_addr.sin6_addr;
 2161                         }
 2162                 }
 2163         }
 2164 
 2165         if (srcp == NULL) {
 2166                 int e;
 2167                 struct sockaddr_in6 sin6;
 2168                 struct route_in6 ro;
 2169 
 2170                 /*
 2171                  * This case matches to multicasts, our anycast, or unicasts
 2172                  * that we do not own.  Select a source address based on the
 2173                  * source address of the erroneous packet.
 2174                  */
 2175                 bzero(&sin6, sizeof(sin6));
 2176                 sin6.sin6_family = AF_INET6;
 2177                 sin6.sin6_len = sizeof(sin6);
 2178                 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */
 2179 
 2180                 bzero(&ro, sizeof(ro));
 2181                 e = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &src);
 2182                 if (ro.ro_rt)
 2183                         RTFREE(ro.ro_rt); /* XXX: we could use this */
 2184                 if (e) {
 2185                         char ip6buf[INET6_ADDRSTRLEN];
 2186                         nd6log((LOG_DEBUG,
 2187                             "icmp6_reflect: source can't be determined: "
 2188                             "dst=%s, error=%d\n",
 2189                             ip6_sprintf(ip6buf, &sin6.sin6_addr), e));
 2190                         goto bad;
 2191                 }
 2192                 srcp = &src;
 2193         }
 2194 
 2195         ip6->ip6_src = *srcp;
 2196         ip6->ip6_flow = 0;
 2197         ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
 2198         ip6->ip6_vfc |= IPV6_VERSION;
 2199         ip6->ip6_nxt = IPPROTO_ICMPV6;
 2200         if (outif)
 2201                 ip6->ip6_hlim = ND_IFINFO(outif)->chlim;
 2202         else if (m->m_pkthdr.rcvif) {
 2203                 /* XXX: This may not be the outgoing interface */
 2204                 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim;
 2205         } else
 2206                 ip6->ip6_hlim = V_ip6_defhlim;
 2207 
 2208         icmp6->icmp6_cksum = 0;
 2209         icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
 2210             sizeof(struct ip6_hdr), plen);
 2211 
 2212         /*
 2213          * XXX option handling
 2214          */
 2215 
 2216         m->m_flags &= ~(M_BCAST|M_MCAST);
 2217 
 2218         ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
 2219         if (outif)
 2220                 icmp6_ifoutstat_inc(outif, type, code);
 2221 
 2222         if (ia != NULL)
 2223                 ifa_free(&ia->ia_ifa);
 2224         return;
 2225 
 2226  bad:
 2227         if (ia != NULL)
 2228                 ifa_free(&ia->ia_ifa);
 2229         m_freem(m);
 2230         return;
 2231 }
 2232 
 2233 void
 2234 icmp6_fasttimo(void)
 2235 {
 2236 
 2237         mld_fasttimo();
 2238 }
 2239 
 2240 void
 2241 icmp6_slowtimo(void)
 2242 {
 2243 
 2244         mld_slowtimo();
 2245 }
 2246 
 2247 static const char *
 2248 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6,
 2249     struct in6_addr *tgt6)
 2250 {
 2251         static char buf[1024];
 2252         char ip6bufs[INET6_ADDRSTRLEN];
 2253         char ip6bufd[INET6_ADDRSTRLEN];
 2254         char ip6buft[INET6_ADDRSTRLEN];
 2255         snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
 2256             ip6_sprintf(ip6bufs, src6), ip6_sprintf(ip6bufd, dst6),
 2257             ip6_sprintf(ip6buft, tgt6));
 2258         return buf;
 2259 }
 2260 
 2261 void
 2262 icmp6_redirect_input(struct mbuf *m, int off)
 2263 {
 2264         struct ifnet *ifp;
 2265         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
 2266         struct nd_redirect *nd_rd;
 2267         int icmp6len = ntohs(ip6->ip6_plen);
 2268         char *lladdr = NULL;
 2269         int lladdrlen = 0;
 2270         struct rtentry *rt = NULL;
 2271         int is_router;
 2272         int is_onlink;
 2273         struct in6_addr src6 = ip6->ip6_src;
 2274         struct in6_addr redtgt6;
 2275         struct in6_addr reddst6;
 2276         union nd_opts ndopts;
 2277         char ip6buf[INET6_ADDRSTRLEN];
 2278 
 2279         if (!m)
 2280                 return;
 2281 
 2282         ifp = m->m_pkthdr.rcvif;
 2283 
 2284         if (!ifp)
 2285                 return;
 2286 
 2287         /* XXX if we are router, we don't update route by icmp6 redirect */
 2288         if (V_ip6_forwarding)
 2289                 goto freeit;
 2290         if (!V_icmp6_rediraccept)
 2291                 goto freeit;
 2292 
 2293 #ifndef PULLDOWN_TEST
 2294         IP6_EXTHDR_CHECK(m, off, icmp6len,);
 2295         nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
 2296 #else
 2297         IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len);
 2298         if (nd_rd == NULL) {
 2299                 ICMP6STAT_INC(icp6s_tooshort);
 2300                 return;
 2301         }
 2302 #endif
 2303         redtgt6 = nd_rd->nd_rd_target;
 2304         reddst6 = nd_rd->nd_rd_dst;
 2305 
 2306         if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) ||
 2307             in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) {
 2308                 goto freeit;
 2309         }
 2310 
 2311         /* validation */
 2312         if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
 2313                 nd6log((LOG_ERR,
 2314                     "ICMP6 redirect sent from %s rejected; "
 2315                     "must be from linklocal\n",
 2316                     ip6_sprintf(ip6buf, &src6)));
 2317                 goto bad;
 2318         }
 2319         if (ip6->ip6_hlim != 255) {
 2320                 nd6log((LOG_ERR,
 2321                     "ICMP6 redirect sent from %s rejected; "
 2322                     "hlim=%d (must be 255)\n",
 2323                     ip6_sprintf(ip6buf, &src6), ip6->ip6_hlim));
 2324                 goto bad;
 2325         }
 2326     {
 2327         /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
 2328         struct sockaddr_in6 sin6;
 2329         struct in6_addr *gw6;
 2330 
 2331         bzero(&sin6, sizeof(sin6));
 2332         sin6.sin6_family = AF_INET6;
 2333         sin6.sin6_len = sizeof(struct sockaddr_in6);
 2334         bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6));
 2335         rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL);
 2336         if (rt) {
 2337                 if (rt->rt_gateway == NULL ||
 2338                     rt->rt_gateway->sa_family != AF_INET6) {
 2339                         nd6log((LOG_ERR,
 2340                             "ICMP6 redirect rejected; no route "
 2341                             "with inet6 gateway found for redirect dst: %s\n",
 2342                             icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
 2343                         RTFREE_LOCKED(rt);
 2344                         goto bad;
 2345                 }
 2346 
 2347                 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
 2348                 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
 2349                         nd6log((LOG_ERR,
 2350                             "ICMP6 redirect rejected; "
 2351                             "not equal to gw-for-src=%s (must be same): "
 2352                             "%s\n",
 2353                             ip6_sprintf(ip6buf, gw6),
 2354                             icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
 2355                         RTFREE_LOCKED(rt);
 2356                         goto bad;
 2357                 }
 2358         } else {
 2359                 nd6log((LOG_ERR,
 2360                     "ICMP6 redirect rejected; "
 2361                     "no route found for redirect dst: %s\n",
 2362                     icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
 2363                 goto bad;
 2364         }
 2365         RTFREE_LOCKED(rt);
 2366         rt = NULL;
 2367     }
 2368         if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
 2369                 nd6log((LOG_ERR,
 2370                     "ICMP6 redirect rejected; "
 2371                     "redirect dst must be unicast: %s\n",
 2372                     icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
 2373                 goto bad;
 2374         }
 2375 
 2376         is_router = is_onlink = 0;
 2377         if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
 2378                 is_router = 1;  /* router case */
 2379         if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
 2380                 is_onlink = 1;  /* on-link destination case */
 2381         if (!is_router && !is_onlink) {
 2382                 nd6log((LOG_ERR,
 2383                     "ICMP6 redirect rejected; "
 2384                     "neither router case nor onlink case: %s\n",
 2385                     icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
 2386                 goto bad;
 2387         }
 2388         /* validation passed */
 2389 
 2390         icmp6len -= sizeof(*nd_rd);
 2391         nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
 2392         if (nd6_options(&ndopts) < 0) {
 2393                 nd6log((LOG_INFO, "icmp6_redirect_input: "
 2394                     "invalid ND option, rejected: %s\n",
 2395                     icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
 2396                 /* nd6_options have incremented stats */
 2397                 goto freeit;
 2398         }
 2399 
 2400         if (ndopts.nd_opts_tgt_lladdr) {
 2401                 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
 2402                 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
 2403         }
 2404 
 2405         if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
 2406                 nd6log((LOG_INFO,
 2407                     "icmp6_redirect_input: lladdrlen mismatch for %s "
 2408                     "(if %d, icmp6 packet %d): %s\n",
 2409                     ip6_sprintf(ip6buf, &redtgt6),
 2410                     ifp->if_addrlen, lladdrlen - 2,
 2411                     icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
 2412                 goto bad;
 2413         }
 2414 
 2415         /* RFC 2461 8.3 */
 2416         nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
 2417             is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
 2418 
 2419         if (!is_onlink) {       /* better router case.  perform rtredirect. */
 2420                 /* perform rtredirect */
 2421                 struct sockaddr_in6 sdst;
 2422                 struct sockaddr_in6 sgw;
 2423                 struct sockaddr_in6 ssrc;
 2424 
 2425                 bzero(&sdst, sizeof(sdst));
 2426                 bzero(&sgw, sizeof(sgw));
 2427                 bzero(&ssrc, sizeof(ssrc));
 2428                 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
 2429                 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
 2430                         sizeof(struct sockaddr_in6);
 2431                 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
 2432                 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
 2433                 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
 2434                 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw,
 2435                     (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST,
 2436                     (struct sockaddr *)&ssrc);
 2437         }
 2438         /* finally update cached route in each socket via pfctlinput */
 2439     {
 2440         struct sockaddr_in6 sdst;
 2441 
 2442         bzero(&sdst, sizeof(sdst));
 2443         sdst.sin6_family = AF_INET6;
 2444         sdst.sin6_len = sizeof(struct sockaddr_in6);
 2445         bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
 2446         pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
 2447 #ifdef IPSEC
 2448         key_sa_routechange((struct sockaddr *)&sdst);
 2449 #endif /* IPSEC */
 2450     }
 2451 
 2452  freeit:
 2453         m_freem(m);
 2454         return;
 2455 
 2456  bad:
 2457         ICMP6STAT_INC(icp6s_badredirect);
 2458         m_freem(m);
 2459 }
 2460 
 2461 void
 2462 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt)
 2463 {
 2464         struct ifnet *ifp;      /* my outgoing interface */
 2465         struct in6_addr *ifp_ll6;
 2466         struct in6_addr *router_ll6;
 2467         struct ip6_hdr *sip6;   /* m0 as struct ip6_hdr */
 2468         struct mbuf *m = NULL;  /* newly allocated one */
 2469         struct ip6_hdr *ip6;    /* m as struct ip6_hdr */
 2470         struct nd_redirect *nd_rd;
 2471         struct llentry *ln = NULL;
 2472         size_t maxlen;
 2473         u_char *p;
 2474         struct ifnet *outif = NULL;
 2475         struct sockaddr_in6 src_sa;
 2476 
 2477         icmp6_errcount(&V_icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0);
 2478 
 2479         /* if we are not router, we don't send icmp6 redirect */
 2480         if (!V_ip6_forwarding)
 2481                 goto fail;
 2482 
 2483         /* sanity check */
 2484         if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp))
 2485                 goto fail;
 2486 
 2487         /*
 2488          * Address check:
 2489          *  the source address must identify a neighbor, and
 2490          *  the destination address must not be a multicast address
 2491          *  [RFC 2461, sec 8.2]
 2492          */
 2493         sip6 = mtod(m0, struct ip6_hdr *);
 2494         bzero(&src_sa, sizeof(src_sa));
 2495         src_sa.sin6_family = AF_INET6;
 2496         src_sa.sin6_len = sizeof(src_sa);
 2497         src_sa.sin6_addr = sip6->ip6_src;
 2498         if (nd6_is_addr_neighbor(&src_sa, ifp) == 0)
 2499                 goto fail;
 2500         if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
 2501                 goto fail;      /* what should we do here? */
 2502 
 2503         /* rate limit */
 2504         if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
 2505                 goto fail;
 2506 
 2507         /*
 2508          * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
 2509          * we almost always ask for an mbuf cluster for simplicity.
 2510          * (MHLEN < IPV6_MMTU is almost always true)
 2511          */
 2512 #if IPV6_MMTU >= MCLBYTES
 2513 # error assumption failed about IPV6_MMTU and MCLBYTES
 2514 #endif
 2515         MGETHDR(m, M_DONTWAIT, MT_HEADER);
 2516         if (m && IPV6_MMTU >= MHLEN)
 2517                 MCLGET(m, M_DONTWAIT);
 2518         if (!m)
 2519                 goto fail;
 2520         m->m_pkthdr.rcvif = NULL;
 2521         m->m_len = 0;
 2522         maxlen = M_TRAILINGSPACE(m);
 2523         maxlen = min(IPV6_MMTU, maxlen);
 2524         /* just for safety */
 2525         if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) +
 2526             ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) {
 2527                 goto fail;
 2528         }
 2529 
 2530         {
 2531                 /* get ip6 linklocal address for ifp(my outgoing interface). */
 2532                 struct in6_ifaddr *ia;
 2533                 if ((ia = in6ifa_ifpforlinklocal(ifp,
 2534                                                  IN6_IFF_NOTREADY|
 2535                                                  IN6_IFF_ANYCAST)) == NULL)
 2536                         goto fail;
 2537                 ifp_ll6 = &ia->ia_addr.sin6_addr;
 2538                 /* XXXRW: reference released prematurely. */
 2539                 ifa_free(&ia->ia_ifa);
 2540         }
 2541 
 2542         /* get ip6 linklocal address for the router. */
 2543         if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
 2544                 struct sockaddr_in6 *sin6;
 2545                 sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
 2546                 router_ll6 = &sin6->sin6_addr;
 2547                 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
 2548                         router_ll6 = (struct in6_addr *)NULL;
 2549         } else
 2550                 router_ll6 = (struct in6_addr *)NULL;
 2551 
 2552         /* ip6 */
 2553         ip6 = mtod(m, struct ip6_hdr *);
 2554         ip6->ip6_flow = 0;
 2555         ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
 2556         ip6->ip6_vfc |= IPV6_VERSION;
 2557         /* ip6->ip6_plen will be set later */
 2558         ip6->ip6_nxt = IPPROTO_ICMPV6;
 2559         ip6->ip6_hlim = 255;
 2560         /* ip6->ip6_src must be linklocal addr for my outgoing if. */
 2561         bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
 2562         bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
 2563 
 2564         /* ND Redirect */
 2565         nd_rd = (struct nd_redirect *)(ip6 + 1);
 2566         nd_rd->nd_rd_type = ND_REDIRECT;
 2567         nd_rd->nd_rd_code = 0;
 2568         nd_rd->nd_rd_reserved = 0;
 2569         if (rt->rt_flags & RTF_GATEWAY) {
 2570                 /*
 2571                  * nd_rd->nd_rd_target must be a link-local address in
 2572                  * better router cases.
 2573                  */
 2574                 if (!router_ll6)
 2575                         goto fail;
 2576                 bcopy(router_ll6, &nd_rd->nd_rd_target,
 2577                     sizeof(nd_rd->nd_rd_target));
 2578                 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
 2579                     sizeof(nd_rd->nd_rd_dst));
 2580         } else {
 2581                 /* make sure redtgt == reddst */
 2582                 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
 2583                     sizeof(nd_rd->nd_rd_target));
 2584                 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
 2585                     sizeof(nd_rd->nd_rd_dst));
 2586         }
 2587 
 2588         p = (u_char *)(nd_rd + 1);
 2589 
 2590         if (!router_ll6)
 2591                 goto nolladdropt;
 2592 
 2593         {
 2594                 /* target lladdr option */
 2595                 int len;
 2596                 struct nd_opt_hdr *nd_opt;
 2597                 char *lladdr;
 2598 
 2599                 IF_AFDATA_LOCK(ifp);
 2600                 ln = nd6_lookup(router_ll6, 0, ifp);
 2601                 IF_AFDATA_UNLOCK(ifp);
 2602                 if (ln == NULL)
 2603                         goto nolladdropt;
 2604 
 2605                 len = sizeof(*nd_opt) + ifp->if_addrlen;
 2606                 len = (len + 7) & ~7;   /* round by 8 */
 2607                 /* safety check */
 2608                 if (len + (p - (u_char *)ip6) > maxlen)                         
 2609                         goto nolladdropt;
 2610 
 2611                 if (ln->la_flags & LLE_VALID) {
 2612                         nd_opt = (struct nd_opt_hdr *)p;
 2613                         nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
 2614                         nd_opt->nd_opt_len = len >> 3;
 2615                         lladdr = (char *)(nd_opt + 1);
 2616                         bcopy(&ln->ll_addr, lladdr, ifp->if_addrlen);
 2617                         p += len;
 2618                 }
 2619         }
 2620 nolladdropt:
 2621         if (ln != NULL)
 2622                 LLE_RUNLOCK(ln);
 2623                 
 2624         m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
 2625 
 2626         /* just to be safe */
 2627 #ifdef M_DECRYPTED      /*not openbsd*/
 2628         if (m0->m_flags & M_DECRYPTED)
 2629                 goto noredhdropt;
 2630 #endif
 2631         if (p - (u_char *)ip6 > maxlen)
 2632                 goto noredhdropt;
 2633 
 2634         {
 2635                 /* redirected header option */
 2636                 int len;
 2637                 struct nd_opt_rd_hdr *nd_opt_rh;
 2638 
 2639                 /*
 2640                  * compute the maximum size for icmp6 redirect header option.
 2641                  * XXX room for auth header?
 2642                  */
 2643                 len = maxlen - (p - (u_char *)ip6);
 2644                 len &= ~7;
 2645 
 2646                 /* This is just for simplicity. */
 2647                 if (m0->m_pkthdr.len != m0->m_len) {
 2648                         if (m0->m_next) {
 2649                                 m_freem(m0->m_next);
 2650                                 m0->m_next = NULL;
 2651                         }
 2652                         m0->m_pkthdr.len = m0->m_len;
 2653                 }
 2654 
 2655                 /*
 2656                  * Redirected header option spec (RFC2461 4.6.3) talks nothing
 2657                  * about padding/truncate rule for the original IP packet.
 2658                  * From the discussion on IPv6imp in Feb 1999,
 2659                  * the consensus was:
 2660                  * - "attach as much as possible" is the goal
 2661                  * - pad if not aligned (original size can be guessed by
 2662                  *   original ip6 header)
 2663                  * Following code adds the padding if it is simple enough,
 2664                  * and truncates if not.
 2665                  */
 2666                 if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
 2667                         panic("assumption failed in %s:%d", __FILE__,
 2668                             __LINE__);
 2669 
 2670                 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
 2671                         /* not enough room, truncate */
 2672                         m0->m_pkthdr.len = m0->m_len = len -
 2673                             sizeof(*nd_opt_rh);
 2674                 } else {
 2675                         /* enough room, pad or truncate */
 2676                         size_t extra;
 2677 
 2678                         extra = m0->m_pkthdr.len % 8;
 2679                         if (extra) {
 2680                                 /* pad if easy enough, truncate if not */
 2681                                 if (8 - extra <= M_TRAILINGSPACE(m0)) {
 2682                                         /* pad */
 2683                                         m0->m_len += (8 - extra);
 2684                                         m0->m_pkthdr.len += (8 - extra);
 2685                                 } else {
 2686                                         /* truncate */
 2687                                         m0->m_pkthdr.len -= extra;
 2688                                         m0->m_len -= extra;
 2689                                 }
 2690                         }
 2691                         len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
 2692                         m0->m_pkthdr.len = m0->m_len = len -
 2693                             sizeof(*nd_opt_rh);
 2694                 }
 2695 
 2696                 nd_opt_rh = (struct nd_opt_rd_hdr *)p;
 2697                 bzero(nd_opt_rh, sizeof(*nd_opt_rh));
 2698                 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
 2699                 nd_opt_rh->nd_opt_rh_len = len >> 3;
 2700                 p += sizeof(*nd_opt_rh);
 2701                 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
 2702 
 2703                 /* connect m0 to m */
 2704                 m_tag_delete_chain(m0, NULL);
 2705                 m0->m_flags &= ~M_PKTHDR;
 2706                 m->m_next = m0;
 2707                 m->m_pkthdr.len = m->m_len + m0->m_len;
 2708                 m0 = NULL;
 2709         }
 2710 noredhdropt:;
 2711         if (m0) {
 2712                 m_freem(m0);
 2713                 m0 = NULL;
 2714         }
 2715 
 2716         /* XXX: clear embedded link IDs in the inner header */
 2717         in6_clearscope(&sip6->ip6_src);
 2718         in6_clearscope(&sip6->ip6_dst);
 2719         in6_clearscope(&nd_rd->nd_rd_target);
 2720         in6_clearscope(&nd_rd->nd_rd_dst);
 2721 
 2722         ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
 2723 
 2724         nd_rd->nd_rd_cksum = 0;
 2725         nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6,
 2726             sizeof(*ip6), ntohs(ip6->ip6_plen));
 2727 
 2728         /* send the packet to outside... */
 2729         ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
 2730         if (outif) {
 2731                 icmp6_ifstat_inc(outif, ifs6_out_msg);
 2732                 icmp6_ifstat_inc(outif, ifs6_out_redirect);
 2733         }
 2734         ICMP6STAT_INC(icp6s_outhist[ND_REDIRECT]);
 2735 
 2736         return;
 2737 
 2738 fail:
 2739         if (m)
 2740                 m_freem(m);
 2741         if (m0)
 2742                 m_freem(m0);
 2743 }
 2744 
 2745 /*
 2746  * ICMPv6 socket option processing.
 2747  */
 2748 int
 2749 icmp6_ctloutput(struct socket *so, struct sockopt *sopt)
 2750 {
 2751         int error = 0;
 2752         int optlen;
 2753         struct inpcb *inp = sotoinpcb(so);
 2754         int level, op, optname;
 2755 
 2756         if (sopt) {
 2757                 level = sopt->sopt_level;
 2758                 op = sopt->sopt_dir;
 2759                 optname = sopt->sopt_name;
 2760                 optlen = sopt->sopt_valsize;
 2761         } else
 2762                 level = op = optname = optlen = 0;
 2763 
 2764         if (level != IPPROTO_ICMPV6) {
 2765                 return EINVAL;
 2766         }
 2767 
 2768         switch (op) {
 2769         case PRCO_SETOPT:
 2770                 switch (optname) {
 2771                 case ICMP6_FILTER:
 2772                     {
 2773                         struct icmp6_filter ic6f;
 2774 
 2775                         if (optlen != sizeof(ic6f)) {
 2776                                 error = EMSGSIZE;
 2777                                 break;
 2778                         }
 2779                         error = sooptcopyin(sopt, &ic6f, optlen, optlen);
 2780                         if (error == 0) {
 2781                                 INP_WLOCK(inp);
 2782                                 *inp->in6p_icmp6filt = ic6f;
 2783                                 INP_WUNLOCK(inp);
 2784                         }
 2785                         break;
 2786                     }
 2787 
 2788                 default:
 2789                         error = ENOPROTOOPT;
 2790                         break;
 2791                 }
 2792                 break;
 2793 
 2794         case PRCO_GETOPT:
 2795                 switch (optname) {
 2796                 case ICMP6_FILTER:
 2797                     {
 2798                         struct icmp6_filter ic6f;
 2799 
 2800                         INP_RLOCK(inp);
 2801                         ic6f = *inp->in6p_icmp6filt;
 2802                         INP_RUNLOCK(inp);
 2803                         error = sooptcopyout(sopt, &ic6f, sizeof(ic6f));
 2804                         break;
 2805                     }
 2806 
 2807                 default:
 2808                         error = ENOPROTOOPT;
 2809                         break;
 2810                 }
 2811                 break;
 2812         }
 2813 
 2814         return (error);
 2815 }
 2816 
 2817 /*
 2818  * Perform rate limit check.
 2819  * Returns 0 if it is okay to send the icmp6 packet.
 2820  * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
 2821  * limitation.
 2822  *
 2823  * XXX per-destination/type check necessary?
 2824  *
 2825  * dst - not used at this moment
 2826  * type - not used at this moment
 2827  * code - not used at this moment
 2828  */
 2829 static int
 2830 icmp6_ratelimit(const struct in6_addr *dst, const int type,
 2831     const int code)
 2832 {
 2833         int ret;
 2834 
 2835         ret = 0;        /* okay to send */
 2836 
 2837         /* PPS limit */
 2838         if (!ppsratecheck(&V_icmp6errppslim_last, &V_icmp6errpps_count,
 2839             V_icmp6errppslim)) {
 2840                 /* The packet is subject to rate limit */
 2841                 ret++;
 2842         }
 2843 
 2844         return ret;
 2845 }

Cache object: 7b134af9f53dc17c88bf37b6035b8b34


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