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icmp6.c
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icmp6.c
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/* $NetBSD: icmp6.c,v 1.156 2010/09/12 16:04:57 drochner Exp $ */
/* $KAME: icmp6.c,v 1.217 2001/06/20 15:03:29 jinmei Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Copyright (c) 1982, 1986, 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: icmp6.c,v 1.156 2010/09/12 16:04:57 drochner Exp $");
#include "opt_inet.h"
#include "opt_ipsec.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <sys/domain.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/route.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/ip6_private.h>
#include <netinet/icmp6.h>
#include <netinet6/icmp6_private.h>
#include <netinet6/mld6_var.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/nd6.h>
#include <netinet6/in6_ifattach.h>
#include <netinet6/ip6protosw.h>
#include <netinet6/scope6_var.h>
#ifdef IPSEC
#include <netinet6/ipsec.h>
#include <netkey/key.h>
#endif
#ifdef FAST_IPSEC
#include <netipsec/ipsec.h>
#include <netipsec/key.h>
#endif
#include "faith.h"
#if defined(NFAITH) && 0 < NFAITH
#include <net/if_faith.h>
#endif
#include <net/net_osdep.h>
extern struct domain inet6domain;
percpu_t *icmp6stat_percpu;
extern struct inpcbtable raw6cbtable;
extern int icmp6errppslim;
static int icmp6errpps_count = 0;
static struct timeval icmp6errppslim_last;
extern int icmp6_nodeinfo;
/*
* List of callbacks to notify when Path MTU changes are made.
*/
struct icmp6_mtudisc_callback {
LIST_ENTRY(icmp6_mtudisc_callback) mc_list;
void (*mc_func)(struct in6_addr *);
};
LIST_HEAD(, icmp6_mtudisc_callback) icmp6_mtudisc_callbacks =
LIST_HEAD_INITIALIZER(&icmp6_mtudisc_callbacks);
static struct rttimer_queue *icmp6_mtudisc_timeout_q = NULL;
extern int pmtu_expire;
/* XXX do these values make any sense? */
static int icmp6_mtudisc_hiwat = 1280;
static int icmp6_mtudisc_lowat = 256;
/*
* keep track of # of redirect routes.
*/
static struct rttimer_queue *icmp6_redirect_timeout_q = NULL;
/* XXX experimental, turned off */
static int icmp6_redirect_hiwat = -1;
static int icmp6_redirect_lowat = -1;
static void icmp6_errcount(u_int, int, int);
static int icmp6_rip6_input(struct mbuf **, int);
static int icmp6_ratelimit(const struct in6_addr *, const int, const int);
static const char *icmp6_redirect_diag(struct in6_addr *,
struct in6_addr *, struct in6_addr *);
static struct mbuf *ni6_input(struct mbuf *, int);
static struct mbuf *ni6_nametodns(const char *, int, int);
static int ni6_dnsmatch(const char *, int, const char *, int);
static int ni6_addrs(struct icmp6_nodeinfo *, struct mbuf *,
struct ifnet **, char *);
static int ni6_store_addrs(struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
struct ifnet *, int);
static int icmp6_notify_error(struct mbuf *, int, int, int);
static struct rtentry *icmp6_mtudisc_clone(struct sockaddr *);
static void icmp6_mtudisc_timeout(struct rtentry *, struct rttimer *);
static void icmp6_redirect_timeout(struct rtentry *, struct rttimer *);
static void sysctl_net_inet6_icmp6_setup(struct sysctllog **);
void
icmp6_init(void)
{
sysctl_net_inet6_icmp6_setup(NULL);
mld_init();
icmp6_mtudisc_timeout_q = rt_timer_queue_create(pmtu_expire);
icmp6_redirect_timeout_q = rt_timer_queue_create(icmp6_redirtimeout);
icmp6stat_percpu = percpu_alloc(sizeof(uint64_t) * ICMP6_NSTATS);
}
static void
icmp6_errcount(u_int base, int type, int code)
{
switch (type) {
case ICMP6_DST_UNREACH:
switch (code) {
case ICMP6_DST_UNREACH_NOROUTE:
ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_NOROUTE);
return;
case ICMP6_DST_UNREACH_ADMIN:
ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_ADMIN);
return;
case ICMP6_DST_UNREACH_BEYONDSCOPE:
ICMP6_STATINC(base +
ICMP6_ERRSTAT_DST_UNREACH_BEYONDSCOPE);
return;
case ICMP6_DST_UNREACH_ADDR:
ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_ADDR);
return;
case ICMP6_DST_UNREACH_NOPORT:
ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_NOPORT);
return;
}
break;
case ICMP6_PACKET_TOO_BIG:
ICMP6_STATINC(base + ICMP6_ERRSTAT_PACKET_TOO_BIG);
return;
case ICMP6_TIME_EXCEEDED:
switch (code) {
case ICMP6_TIME_EXCEED_TRANSIT:
ICMP6_STATINC(base + ICMP6_ERRSTAT_TIME_EXCEED_TRANSIT);
return;
case ICMP6_TIME_EXCEED_REASSEMBLY:
ICMP6_STATINC(base +
ICMP6_ERRSTAT_TIME_EXCEED_REASSEMBLY);
return;
}
break;
case ICMP6_PARAM_PROB:
switch (code) {
case ICMP6_PARAMPROB_HEADER:
ICMP6_STATINC(base + ICMP6_ERRSTAT_PARAMPROB_HEADER);
return;
case ICMP6_PARAMPROB_NEXTHEADER:
ICMP6_STATINC(base +
ICMP6_ERRSTAT_PARAMPROB_NEXTHEADER);
return;
case ICMP6_PARAMPROB_OPTION:
ICMP6_STATINC(base + ICMP6_ERRSTAT_PARAMPROB_OPTION);
return;
}
break;
case ND_REDIRECT:
ICMP6_STATINC(base + ICMP6_ERRSTAT_REDIRECT);
return;
}
ICMP6_STATINC(base + ICMP6_ERRSTAT_UNKNOWN);
}
/*
* Register a Path MTU Discovery callback.
*/
void
icmp6_mtudisc_callback_register(void (*func)(struct in6_addr *))
{
struct icmp6_mtudisc_callback *mc;
for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL;
mc = LIST_NEXT(mc, mc_list)) {
if (mc->mc_func == func)
return;
}
mc = malloc(sizeof(*mc), M_PCB, M_NOWAIT);
if (mc == NULL)
panic("icmp6_mtudisc_callback_register");
mc->mc_func = func;
LIST_INSERT_HEAD(&icmp6_mtudisc_callbacks, mc, mc_list);
}
/*
* A wrapper function for icmp6_error() necessary when the erroneous packet
* may not contain enough scope zone information.
*/
void
icmp6_error2(struct mbuf *m, int type, int code, int param,
struct ifnet *ifp)
{
struct ip6_hdr *ip6;
if (ifp == NULL)
return;
if (m->m_len < sizeof(struct ip6_hdr)) {
m = m_pullup(m, sizeof(struct ip6_hdr));
if (m == NULL)
return;
}
ip6 = mtod(m, struct ip6_hdr *);
if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0)
return;
if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
return;
icmp6_error(m, type, code, param);
}
/*
* Generate an error packet of type error in response to bad IP6 packet.
*/
void
icmp6_error(struct mbuf *m, int type, int code, int param)
{
struct ip6_hdr *oip6, *nip6;
struct icmp6_hdr *icmp6;
u_int preplen;
int off;
int nxt;
ICMP6_STATINC(ICMP6_STAT_ERROR);
/* count per-type-code statistics */
icmp6_errcount(ICMP6_STAT_OUTERRHIST, type, code);
if (m->m_flags & M_DECRYPTED) {
ICMP6_STATINC(ICMP6_STAT_CANTERROR);
goto freeit;
}
if (M_UNWRITABLE(m, sizeof(struct ip6_hdr)) &&
(m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL)
return;
oip6 = mtod(m, struct ip6_hdr *);
/*
* If the destination address of the erroneous packet is a multicast
* address, or the packet was sent using link-layer multicast,
* we should basically suppress sending an error (RFC 2463, Section
* 2.4).
* We have two exceptions (the item e.2 in that section):
* - the Pakcet Too Big message can be sent for path MTU discovery.
* - the Parameter Problem Message that can be allowed an icmp6 error
* in the option type field. This check has been done in
* ip6_unknown_opt(), so we can just check the type and code.
*/
if ((m->m_flags & (M_BCAST|M_MCAST) ||
IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
(type != ICMP6_PACKET_TOO_BIG &&
(type != ICMP6_PARAM_PROB ||
code != ICMP6_PARAMPROB_OPTION)))
goto freeit;
/*
* RFC 2463, 2.4 (e.5): source address check.
* XXX: the case of anycast source?
*/
if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
goto freeit;
/*
* If we are about to send ICMPv6 against ICMPv6 error/redirect,
* don't do it.
*/
nxt = -1;
off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
if (off >= 0 && nxt == IPPROTO_ICMPV6) {
struct icmp6_hdr *icp;
IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
sizeof(*icp));
if (icp == NULL) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
return;
}
if (icp->icmp6_type < ICMP6_ECHO_REQUEST ||
icp->icmp6_type == ND_REDIRECT) {
/*
* ICMPv6 error
* Special case: for redirect (which is
* informational) we must not send icmp6 error.
*/
ICMP6_STATINC(ICMP6_STAT_CANTERROR);
goto freeit;
} else {
/* ICMPv6 informational - send the error */
}
}
#if 0 /* controversial */
else if (off >= 0 && nxt == IPPROTO_ESP) {
/*
* It could be ICMPv6 error inside ESP. Take a safer side,
* don't respond.
*/
ICMP6_STATINC(ICMP6_STAT_CANTERROR);
goto freeit;
}
#endif
else {
/* non-ICMPv6 - send the error */
}
oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
/* Finally, do rate limitation check. */
if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
ICMP6_STATINC(ICMP6_STAT_TOOFREQ);
goto freeit;
}
/*
* OK, ICMP6 can be generated.
*/
if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
M_PREPEND(m, preplen, M_DONTWAIT);
if (m && M_UNWRITABLE(m, preplen))
m = m_pullup(m, preplen);
if (m == NULL) {
nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__));
return;
}
nip6 = mtod(m, struct ip6_hdr *);
nip6->ip6_src = oip6->ip6_src;
nip6->ip6_dst = oip6->ip6_dst;
in6_clearscope(&oip6->ip6_src);
in6_clearscope(&oip6->ip6_dst);
icmp6 = (struct icmp6_hdr *)(nip6 + 1);
icmp6->icmp6_type = type;
icmp6->icmp6_code = code;
icmp6->icmp6_pptr = htonl((u_int32_t)param);
/*
* icmp6_reflect() is designed to be in the input path.
* icmp6_error() can be called from both input and output path,
* and if we are in output path rcvif could contain bogus value.
* clear m->m_pkthdr.rcvif for safety, we should have enough scope
* information in ip header (nip6).
*/
m->m_pkthdr.rcvif = NULL;
ICMP6_STATINC(ICMP6_STAT_OUTHIST + type);
icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */
return;
freeit:
/*
* If we can't tell whether or not we can generate ICMP6, free it.
*/
m_freem(m);
}
/*
* Process a received ICMP6 message.
*/
int
icmp6_input(struct mbuf **mp, int *offp, int proto)
{
struct mbuf *m = *mp, *n;
struct ip6_hdr *ip6, *nip6;
struct icmp6_hdr *icmp6, *nicmp6;
int off = *offp;
int icmp6len = m->m_pkthdr.len - *offp;
int code, sum, noff, i;
#define ICMP6_MAXLEN (sizeof(*nip6) + sizeof(*nicmp6) + 4)
KASSERT(ICMP6_MAXLEN < MCLBYTES);
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg);
/*
* Locate icmp6 structure in mbuf, and check
* that not corrupted and of at least minimum length
*/
if (icmp6len < sizeof(struct icmp6_hdr)) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);
goto freeit;
}
i = off + sizeof(*icmp6);
if ((m->m_len < i || M_READONLY(m)) && (m = m_pullup(m, i)) == 0) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
#if 0 /* m is 0 here */
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);
#endif
goto freeit;
}
ip6 = mtod(m, struct ip6_hdr *);
/*
* calculate the checksum
*/
IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
if (icmp6 == NULL) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
/* m is invalid */
/*icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);*/
return IPPROTO_DONE;
}
KASSERT(IP6_HDR_ALIGNED_P(icmp6));
code = icmp6->icmp6_code;
if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
nd6log((LOG_ERR,
"ICMP6 checksum error(%d|%x) %s\n",
icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src)));
ICMP6_STATINC(ICMP6_STAT_CHECKSUM);
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);
goto freeit;
}
#if defined(NFAITH) && 0 < NFAITH
if (faithprefix(&ip6->ip6_dst)) {
/*
* Deliver very specific ICMP6 type only.
* This is important to deliver TOOBIG. Otherwise PMTUD
* will not work.
*/
switch (icmp6->icmp6_type) {
case ICMP6_DST_UNREACH:
case ICMP6_PACKET_TOO_BIG:
case ICMP6_TIME_EXCEEDED:
break;
default:
goto freeit;
}
}
#endif
ICMP6_STATINC(ICMP6_STAT_INHIST + icmp6->icmp6_type);
switch (icmp6->icmp6_type) {
case ICMP6_DST_UNREACH:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach);
switch (code) {
case ICMP6_DST_UNREACH_NOROUTE:
code = PRC_UNREACH_NET;
break;
case ICMP6_DST_UNREACH_ADMIN:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib);
code = PRC_UNREACH_PROTOCOL; /* is this a good code? */
break;
case ICMP6_DST_UNREACH_ADDR:
code = PRC_HOSTDEAD;
break;
#ifdef COMPAT_RFC1885
case ICMP6_DST_UNREACH_NOTNEIGHBOR:
code = PRC_UNREACH_SRCFAIL;
break;
#else
case ICMP6_DST_UNREACH_BEYONDSCOPE:
/* I mean "source address was incorrect." */
code = PRC_UNREACH_NET;
break;
#endif
case ICMP6_DST_UNREACH_NOPORT:
code = PRC_UNREACH_PORT;
break;
default:
goto badcode;
}
goto deliver;
case ICMP6_PACKET_TOO_BIG:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig);
/*
* MTU is checked in icmp6_mtudisc.
*/
code = PRC_MSGSIZE;
/*
* Updating the path MTU will be done after examining
* intermediate extension headers.
*/
goto deliver;
case ICMP6_TIME_EXCEEDED:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed);
switch (code) {
case ICMP6_TIME_EXCEED_TRANSIT:
code = PRC_TIMXCEED_INTRANS;
break;
case ICMP6_TIME_EXCEED_REASSEMBLY:
code = PRC_TIMXCEED_REASS;
break;
default:
goto badcode;
}
goto deliver;
case ICMP6_PARAM_PROB:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob);
switch (code) {
case ICMP6_PARAMPROB_NEXTHEADER:
code = PRC_UNREACH_PROTOCOL;
break;
case ICMP6_PARAMPROB_HEADER:
case ICMP6_PARAMPROB_OPTION:
code = PRC_PARAMPROB;
break;
default:
goto badcode;
}
goto deliver;
case ICMP6_ECHO_REQUEST:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo);
if (code != 0)
goto badcode;
/*
* Copy mbuf to send to two data paths: userland socket(s),
* and to the querier (echo reply).
* m: a copy for socket, n: a copy for querier
*
* If the first mbuf is shared, or the first mbuf is too short,
* copy the first part of the data into a fresh mbuf.
* Otherwise, we will wrongly overwrite both copies.
*/
if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
/* Give up local */
n = m;
m = NULL;
} else if (M_READONLY(n) ||
n->m_len < off + sizeof(struct icmp6_hdr)) {
struct mbuf *n0 = n;
/*
* Prepare an internal mbuf. m_pullup() doesn't
* always copy the length we specified.
*/
if ((n = m_dup(n0, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
/* Give up local */
n = m;
m = NULL;
}
m_freem(n0);
}
IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off,
sizeof(*nicmp6));
nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
nicmp6->icmp6_code = 0;
if (n) {
uint64_t *icmp6s = ICMP6_STAT_GETREF();
icmp6s[ICMP6_STAT_REFLECT]++;
icmp6s[ICMP6_STAT_OUTHIST + ICMP6_ECHO_REPLY]++;
ICMP6_STAT_PUTREF();
icmp6_reflect(n, off);
}
if (!m)
goto freeit;
break;
case ICMP6_ECHO_REPLY:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply);
if (code != 0)
goto badcode;
break;
case MLD_LISTENER_QUERY:
case MLD_LISTENER_REPORT:
if (icmp6len < sizeof(struct mld_hdr))
goto badlen;
if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery);
else
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport);
if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
/* give up local */
mld_input(m, off);
m = NULL;
goto freeit;
}
mld_input(n, off);
/* m stays. */
break;
case MLD_LISTENER_DONE:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone);
if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */
goto badlen;
break; /* nothing to be done in kernel */
case MLD_MTRACE_RESP:
case MLD_MTRACE:
/* XXX: these two are experimental. not officially defined. */
/* XXX: per-interface statistics? */
break; /* just pass it to applications */
case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */
{
enum { WRU, FQDN } mode;
if (!icmp6_nodeinfo)
break;
if (icmp6len == sizeof(struct icmp6_hdr) + 4)
mode = WRU;
else if (icmp6len >= sizeof(struct icmp6_nodeinfo))
mode = FQDN;
else
goto badlen;
if (mode == FQDN) {
n = m_copym(m, 0, M_COPYALL, M_DONTWAIT);
if (n)
n = ni6_input(n, off);
/* XXX meaningless if n == NULL */
noff = sizeof(struct ip6_hdr);
} else {
u_char *p;
int maxhlen;
if ((icmp6_nodeinfo & 5) != 5)
break;
if (code != 0)
goto badcode;
MGETHDR(n, M_DONTWAIT, m->m_type);
if (n && ICMP6_MAXLEN > MHLEN) {
MCLGET(n, M_DONTWAIT);
if ((n->m_flags & M_EXT) == 0) {
m_free(n);
n = NULL;
}
}
if (n == NULL) {
/* Give up remote */
break;
}
n->m_pkthdr.rcvif = NULL;
n->m_len = 0;
maxhlen = M_TRAILINGSPACE(n) - ICMP6_MAXLEN;
if (maxhlen > hostnamelen)
maxhlen = hostnamelen;
/*
* Copy IPv6 and ICMPv6 only.
*/
nip6 = mtod(n, struct ip6_hdr *);
bcopy(ip6, nip6, sizeof(struct ip6_hdr));
nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
p = (u_char *)(nicmp6 + 1);
memset(p, 0, 4);
bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */
noff = sizeof(struct ip6_hdr);
M_COPY_PKTHDR(n, m); /* just for rcvif */
n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
sizeof(struct icmp6_hdr) + 4 + maxhlen;
nicmp6->icmp6_type = ICMP6_WRUREPLY;
nicmp6->icmp6_code = 0;
}
#undef hostnamelen
if (n) {
uint64_t *icmp6s = ICMP6_STAT_GETREF();
icmp6s[ICMP6_STAT_REFLECT]++;
icmp6s[ICMP6_STAT_OUTHIST + ICMP6_WRUREPLY]++;
ICMP6_STAT_PUTREF();
icmp6_reflect(n, noff);
}
break;
}
case ICMP6_WRUREPLY:
if (code != 0)
goto badcode;
break;
case ND_ROUTER_SOLICIT:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit);
if (code != 0)
goto badcode;
if (icmp6len < sizeof(struct nd_router_solicit))
goto badlen;
if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
/* give up local */
nd6_rs_input(m, off, icmp6len);
m = NULL;
goto freeit;
}
nd6_rs_input(n, off, icmp6len);
/* m stays. */
break;
case ND_ROUTER_ADVERT:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert);
if (code != 0)
goto badcode;
if (icmp6len < sizeof(struct nd_router_advert))
goto badlen;
if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
/* give up local */
nd6_ra_input(m, off, icmp6len);
m = NULL;
goto freeit;
}
nd6_ra_input(n, off, icmp6len);
/* m stays. */
break;
case ND_NEIGHBOR_SOLICIT:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit);
if (code != 0)
goto badcode;
if (icmp6len < sizeof(struct nd_neighbor_solicit))
goto badlen;
if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
/* give up local */
nd6_ns_input(m, off, icmp6len);
m = NULL;
goto freeit;
}
nd6_ns_input(n, off, icmp6len);
/* m stays. */
break;
case ND_NEIGHBOR_ADVERT:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert);
if (code != 0)
goto badcode;
if (icmp6len < sizeof(struct nd_neighbor_advert))
goto badlen;
if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
/* give up local */
nd6_na_input(m, off, icmp6len);
m = NULL;
goto freeit;
}
nd6_na_input(n, off, icmp6len);
/* m stays. */
break;
case ND_REDIRECT:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect);
if (code != 0)
goto badcode;
if (icmp6len < sizeof(struct nd_redirect))
goto badlen;
if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
/* give up local */
icmp6_redirect_input(m, off);
m = NULL;
goto freeit;
}
icmp6_redirect_input(n, off);
/* m stays. */
break;
case ICMP6_ROUTER_RENUMBERING:
if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
code != ICMP6_ROUTER_RENUMBERING_RESULT)
goto badcode;
if (icmp6len < sizeof(struct icmp6_router_renum))
goto badlen;
break;
default:
nd6log((LOG_DEBUG,
"icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src),
ip6_sprintf(&ip6->ip6_dst),
m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0));
if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
/* ICMPv6 error: MUST deliver it by spec... */
code = PRC_NCMDS;
/* deliver */
} else {
/* ICMPv6 informational: MUST not deliver */
break;
}
deliver:
if (icmp6_notify_error(m, off, icmp6len, code)) {
/* In this case, m should've been freed. */
return (IPPROTO_DONE);
}
break;
badcode:
ICMP6_STATINC(ICMP6_STAT_BADCODE);
break;
badlen:
ICMP6_STATINC(ICMP6_STAT_BADLEN);
break;
}
/* deliver the packet to appropriate sockets */
icmp6_rip6_input(&m, *offp);
return IPPROTO_DONE;
freeit:
m_freem(m);
return IPPROTO_DONE;
}
static int
icmp6_notify_error(struct mbuf *m, int off, int icmp6len, int code)
{
struct icmp6_hdr *icmp6;
struct ip6_hdr *eip6;
u_int32_t notifymtu;
struct sockaddr_in6 icmp6src, icmp6dst;
if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
goto freeit;
}
IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
sizeof(*icmp6) + sizeof(struct ip6_hdr));
if (icmp6 == NULL) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
return (-1);
}
eip6 = (struct ip6_hdr *)(icmp6 + 1);
/* Detect the upper level protocol */
{
void (*ctlfunc)(int, struct sockaddr *, void *);
u_int8_t nxt = eip6->ip6_nxt;
int eoff = off + sizeof(struct icmp6_hdr) +
sizeof(struct ip6_hdr);
struct ip6ctlparam ip6cp;
struct in6_addr *finaldst = NULL;
int icmp6type = icmp6->icmp6_type;
struct ip6_frag *fh;
struct ip6_rthdr *rth;
struct ip6_rthdr0 *rth0;
int rthlen;
while (1) { /* XXX: should avoid infinite loop explicitly? */
struct ip6_ext *eh;
switch (nxt) {
case IPPROTO_HOPOPTS:
case IPPROTO_DSTOPTS:
case IPPROTO_AH:
IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
eoff, sizeof(*eh));
if (eh == NULL) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
return (-1);
}
if (nxt == IPPROTO_AH)
eoff += (eh->ip6e_len + 2) << 2;
else
eoff += (eh->ip6e_len + 1) << 3;
nxt = eh->ip6e_nxt;
break;
case IPPROTO_ROUTING:
/*
* When the erroneous packet contains a
* routing header, we should examine the
* header to determine the final destination.
* Otherwise, we can't properly update
* information that depends on the final
* destination (e.g. path MTU).
*/
IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m,
eoff, sizeof(*rth));
if (rth == NULL) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
return (-1);
}
rthlen = (rth->ip6r_len + 1) << 3;
/*
* XXX: currently there is no
* officially defined type other
* than type-0.
* Note that if the segment left field
* is 0, all intermediate hops must
* have been passed.
*/
if (rth->ip6r_segleft &&
rth->ip6r_type == IPV6_RTHDR_TYPE_0) {
int hops;
IP6_EXTHDR_GET(rth0,
struct ip6_rthdr0 *, m,
eoff, rthlen);
if (rth0 == NULL) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
return (-1);
}
/* just ignore a bogus header */
if ((rth0->ip6r0_len % 2) == 0 &&
(hops = rth0->ip6r0_len/2))
finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1);
}
eoff += rthlen;
nxt = rth->ip6r_nxt;
break;
case IPPROTO_FRAGMENT:
IP6_EXTHDR_GET(fh, struct ip6_frag *, m,
eoff, sizeof(*fh));
if (fh == NULL) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
return (-1);
}
/*
* Data after a fragment header is meaningless
* unless it is the first fragment, but