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c302f5bc07
freebsd/sys/netinet6/icmp6.c
Hajimu UMEMOTO f95d46333d Switch Advanced Sockets API for IPv6 from RFC2292 to RFC3542 
(aka RFC2292bis).  Though I believe this commit doesn't break
backward compatibility againt existing binaries, it breaks
backward compatibility of API.
Now, the applications which use Advanced Sockets API such as
telnet, ping6, mld6query and traceroute6 use RFC3542 API.

Obtained from:	KAME
2003-10-24 18:26:30 +00:00

2795 lines
71 KiB
C
Raw Blame History

/* $FreeBSD$ */
/* $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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 "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include <sys/param.h>
#include <sys/domain.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/signalvar.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sx.h>
#include <sys/syslog.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_pcb.h>
#include <netinet/in_var.h>
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include <netinet6/in6_ifattach.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/ip6protosw.h>
#include <netinet6/ip6_var.h>
#include <netinet6/mld6_var.h>
#include <netinet6/nd6.h>
#ifdef IPSEC
#include <netinet6/ipsec.h>
#include <netkey/key.h>
#endif
#ifdef FAST_IPSEC
#include <netipsec/ipsec.h>
#include <netipsec/key.h>
#define IPSEC
#endif
#include <net/net_osdep.h>
extern struct domain inet6domain;
struct icmp6stat icmp6stat;
extern struct inpcbhead ripcb;
extern int icmp6errppslim;
static int icmp6errpps_count = 0;
static struct timeval icmp6errppslim_last;
extern int icmp6_nodeinfo;
static void icmp6_errcount __P((struct icmp6errstat *, int, int));
static int icmp6_rip6_input __P((struct mbuf **, int));
static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int));
static const char *icmp6_redirect_diag __P((struct in6_addr *,
struct in6_addr *, struct in6_addr *));
static struct mbuf *ni6_input __P((struct mbuf *, int));
static struct mbuf *ni6_nametodns __P((const char *, int, int));
static int ni6_dnsmatch __P((const char *, int, const char *, int));
static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *,
struct ifnet **, char *));
static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
struct ifnet *, int));
static int icmp6_notify_error __P((struct mbuf *, int, int, int));
#ifdef COMPAT_RFC1885
static struct route_in6 icmp6_reflect_rt;
#endif
void
icmp6_init()
{
mld6_init();
}
static void
icmp6_errcount(stat, type, code)
struct icmp6errstat *stat;
int type, code;
{
switch (type) {
case ICMP6_DST_UNREACH:
switch (code) {
case ICMP6_DST_UNREACH_NOROUTE:
stat->icp6errs_dst_unreach_noroute++;
return;
case ICMP6_DST_UNREACH_ADMIN:
stat->icp6errs_dst_unreach_admin++;
return;
case ICMP6_DST_UNREACH_BEYONDSCOPE:
stat->icp6errs_dst_unreach_beyondscope++;
return;
case ICMP6_DST_UNREACH_ADDR:
stat->icp6errs_dst_unreach_addr++;
return;
case ICMP6_DST_UNREACH_NOPORT:
stat->icp6errs_dst_unreach_noport++;
return;
}
break;
case ICMP6_PACKET_TOO_BIG:
stat->icp6errs_packet_too_big++;
return;
case ICMP6_TIME_EXCEEDED:
switch (code) {
case ICMP6_TIME_EXCEED_TRANSIT:
stat->icp6errs_time_exceed_transit++;
return;
case ICMP6_TIME_EXCEED_REASSEMBLY:
stat->icp6errs_time_exceed_reassembly++;
return;
}
break;
case ICMP6_PARAM_PROB:
switch (code) {
case ICMP6_PARAMPROB_HEADER:
stat->icp6errs_paramprob_header++;
return;
case ICMP6_PARAMPROB_NEXTHEADER:
stat->icp6errs_paramprob_nextheader++;
return;
case ICMP6_PARAMPROB_OPTION:
stat->icp6errs_paramprob_option++;
return;
}
break;
case ND_REDIRECT:
stat->icp6errs_redirect++;
return;
}
stat->icp6errs_unknown++;
}
/*
* Generate an error packet of type error in response to bad IP6 packet.
*/
void
icmp6_error(m, type, code, param)
struct mbuf *m;
int type, code, param;
{
struct ip6_hdr *oip6, *nip6;
struct icmp6_hdr *icmp6;
u_int preplen;
int off;
int nxt;
icmp6stat.icp6s_error++;
/* count per-type-code statistics */
icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code);
#ifdef M_DECRYPTED /*not openbsd*/
if (m->m_flags & M_DECRYPTED) {
icmp6stat.icp6s_canterror++;
goto freeit;
}
#endif
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
#else
if (m->m_len < sizeof(struct ip6_hdr)) {
m = m_pullup(m, sizeof(struct ip6_hdr));
if (m == NULL)
return;
}
#endif
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;
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
#else
IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
sizeof(*icp));
if (icp == NULL) {
icmp6stat.icp6s_tooshort++;
return;
}
#endif
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.
*/
icmp6stat.icp6s_canterror++;
goto freeit;
} else {
/* ICMPv6 informational - send the error */
}
} 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)) {
icmp6stat.icp6s_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->m_len < 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 outut 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;
icmp6stat.icp6s_outhist[type]++;
icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */
return;
freeit:
/*
* If we can't tell wheter or not we can generate ICMP6, free it.
*/
m_freem(m);
}
/*
* Process a received ICMP6 message.
*/
int
icmp6_input(mp, offp, proto)
struct mbuf **mp;
int *offp, 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;
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
/* m might change if M_LOOP. So, call mtod after this */
#endif
/*
* Locate icmp6 structure in mbuf, and check
* that not corrupted and of at least minimum length
*/
ip6 = mtod(m, struct ip6_hdr *);
if (icmp6len < sizeof(struct icmp6_hdr)) {
icmp6stat.icp6s_tooshort++;
goto freeit;
}
/*
* calculate the checksum
*/
#ifndef PULLDOWN_TEST
icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
#else
IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
if (icmp6 == NULL) {
icmp6stat.icp6s_tooshort++;
return IPPROTO_DONE;
}
#endif
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)));
icmp6stat.icp6s_checksum++;
goto freeit;
}
if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) {
/*
* Deliver very specific ICMP6 type only.
* This is important to deilver 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;
}
}
icmp6stat.icp6s_inhist[icmp6->icmp6_type]++;
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg);
if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);
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_PARAMPROB;
break;
#endif
case ICMP6_DST_UNREACH_NOPORT:
code = PRC_UNREACH_PORT;
break;
default:
goto badcode;
}
goto deliver;
break;
case ICMP6_PACKET_TOO_BIG:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig);
if (code != 0)
goto badcode;
code = PRC_MSGSIZE;
/*
* Updating the path MTU will be done after examining
* intermediate extension headers.
*/
goto deliver;
break;
case ICMP6_TIME_EXCEEDED:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed);
switch (code) {
case ICMP6_TIME_EXCEED_TRANSIT:
case ICMP6_TIME_EXCEED_REASSEMBLY:
code += PRC_TIMXCEED_INTRANS;
break;
default:
goto badcode;
}
goto deliver;
break;
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;
break;
case ICMP6_ECHO_REQUEST:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo);
if (code != 0)
goto badcode;
if ((n = m_copy(m, 0, M_COPYALL)) == NULL) {
/* Give up remote */
break;
}
if ((n->m_flags & M_EXT) != 0
|| n->m_len < off + sizeof(struct icmp6_hdr)) {
struct mbuf *n0 = n;
const int maxlen = sizeof(*nip6) + sizeof(*nicmp6);
int n0len;
/*
* Prepare an internal mbuf. m_pullup() doesn't
* always copy the length we specified.
*/
if (maxlen >= MCLBYTES) {
/* Give up remote */
m_freem(n0);
break;
}
MGETHDR(n, M_DONTWAIT, n0->m_type);
n0len = n0->m_pkthdr.len; /* save for use below */
if (n)
M_MOVE_PKTHDR(n, n0);
if (n && maxlen >= MHLEN) {
MCLGET(n, M_DONTWAIT);
if ((n->m_flags & M_EXT) == 0) {
m_free(n);
n = NULL;
}
}
if (n == NULL) {
/* Give up remote */
m_freem(n0);
break;
}
/*
* 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));
noff = sizeof(struct ip6_hdr);
/* new mbuf contains only ipv6+icmpv6 headers */
n->m_len = noff + sizeof(struct icmp6_hdr);
/*
* Adjust mbuf. ip6_plen will be adjusted in
* ip6_output().
*/
m_adj(n0, off + sizeof(struct icmp6_hdr));
/* recalculate complete packet size */
n->m_pkthdr.len = n0len + (noff - off);
n->m_next = n0;
} else {
nip6 = mtod(n, struct ip6_hdr *);
nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off);
noff = off;
}
nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
nicmp6->icmp6_code = 0;
if (n) {
icmp6stat.icp6s_reflect++;
icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++;
icmp6_reflect(n, noff);
}
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 */
mld6_input(m, off);
m = NULL;
goto freeit;
}
mld6_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;
#define hostnamelen strlen(hostname)
if (mode == FQDN) {
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
IPPROTO_DONE);
#endif
n = m_copy(m, 0, M_COPYALL);
if (n)
n = ni6_input(n, off);
/* XXX meaningless if n == NULL */
noff = sizeof(struct ip6_hdr);
} else {
u_char *p;
int maxlen, maxhlen;
if ((icmp6_nodeinfo & 5) != 5)
break;
if (code != 0)
goto badcode;
maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4;
if (maxlen >= MCLBYTES) {
/* Give up remote */
break;
}
MGETHDR(n, M_DONTWAIT, m->m_type);
if (n && maxlen > MHLEN) {
MCLGET(n, M_DONTWAIT);
if ((n->m_flags & M_EXT) == 0) {
m_free(n);
n = NULL;
}
}
if (!m_dup_pkthdr(n, m, M_DONTWAIT)) {
/*
* Previous code did a blind M_COPY_PKTHDR
* and said "just for rcvif". If true, then
* we could tolerate the dup failing (due to
* the deep copy of the tag chain). For now
* be conservative and just fail.
*/
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) - 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);
bzero(p, 4);
bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */
noff = sizeof(struct ip6_hdr);
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) {
icmp6stat.icp6s_reflect++;
icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++;
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:
icmp6stat.icp6s_badcode++;
break;
badlen:
icmp6stat.icp6s_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(m, off, icmp6len, code)
struct mbuf *m;
int off, icmp6len, 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)) {
icmp6stat.icp6s_tooshort++;
goto freeit;
}
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off,
sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1);
icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
#else
IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
sizeof(*icmp6) + sizeof(struct ip6_hdr));
if (icmp6 == NULL) {
icmp6stat.icp6s_tooshort++;
return (-1);
}
#endif
eip6 = (struct ip6_hdr *)(icmp6 + 1);
/* Detect the upper level protocol */
{
void (*ctlfunc) __P((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:
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, 0,
eoff + sizeof(struct ip6_ext), -1);
eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff);
#else
IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
eoff, sizeof(*eh));
if (eh == NULL) {
icmp6stat.icp6s_tooshort++;
return (-1);
}
#endif
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).
*/
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1);
rth = (struct ip6_rthdr *)
(mtod(m, caddr_t) + eoff);
#else
IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m,
eoff, sizeof(*rth));
if (rth == NULL) {
icmp6stat.icp6s_tooshort++;
return (-1);
}
#endif
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;
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1);
rth0 = (struct ip6_rthdr0 *)
(mtod(m, caddr_t) + eoff);
#else
IP6_EXTHDR_GET(rth0,
struct ip6_rthdr0 *, m,
eoff, rthlen);
if (rth0 == NULL) {
icmp6stat.icp6s_tooshort++;
return (-1);
}
#endif
/* 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:
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, 0, eoff +
sizeof(struct ip6_frag), -1);
fh = (struct ip6_frag *)(mtod(m, caddr_t) +
eoff);
#else
IP6_EXTHDR_GET(fh, struct ip6_frag *, m,
eoff, sizeof(*fh));
if (fh == NULL) {
icmp6stat.icp6s_tooshort++;
return (-1);
}
#endif
/*
* Data after a fragment header is meaningless
* unless it is the first fragment, but
* we'll go to the notify label for path MTU
* discovery.
*/
if (fh->ip6f_offlg & IP6F_OFF_MASK)
goto notify;
eoff += sizeof(struct ip6_frag);
nxt = fh->ip6f_nxt;
break;
default:
/*
* This case includes ESP and the No Next
* Header. In such cases going to the notify
* label does not have any meaning
* (i.e. ctlfunc will be NULL), but we go
* anyway since we might have to update
* path MTU information.
*/
goto notify;
}
}
notify:
#ifndef PULLDOWN_TEST
icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
#else
IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
sizeof(*icmp6) + sizeof(struct ip6_hdr));
if (icmp6 == NULL) {
icmp6stat.icp6s_tooshort++;
return (-1);
}
#endif
/*
* retrieve parameters from the inner IPv6 header, and convert
* them into sockaddr structures.
* XXX: there is no guarantee that the source or destination
* addresses of the inner packet are in the same scope as
* the addresses of the icmp packet. But there is no other
* way to determine the zone.
*/
eip6 = (struct ip6_hdr *)(icmp6 + 1);
bzero(&icmp6dst, sizeof(icmp6dst));
icmp6dst.sin6_len = sizeof(struct sockaddr_in6);
icmp6dst.sin6_family = AF_INET6;
if (finaldst == NULL)
icmp6dst.sin6_addr = eip6->ip6_dst;
else
icmp6dst.sin6_addr = *finaldst;
if (in6_addr2zoneid(m->m_pkthdr.rcvif, &icmp6dst.sin6_addr,
&icmp6dst.sin6_scope_id))
goto freeit;
if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst,
NULL, NULL)) {
/* should be impossbile */
nd6log((LOG_DEBUG,
"icmp6_notify_error: in6_embedscope failed\n"));
goto freeit;
}
/*
* retrieve parameters from the inner IPv6 header, and convert
* them into sockaddr structures.
*/
bzero(&icmp6src, sizeof(icmp6src));
icmp6src.sin6_len = sizeof(struct sockaddr_in6);
icmp6src.sin6_family = AF_INET6;
icmp6src.sin6_addr = eip6->ip6_src;
if (in6_addr2zoneid(m->m_pkthdr.rcvif, &icmp6src.sin6_addr,
&icmp6src.sin6_scope_id)) {
goto freeit;
}
if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src,
NULL, NULL)) {
/* should be impossbile */
nd6log((LOG_DEBUG,
"icmp6_notify_error: in6_embedscope failed\n"));
goto freeit;
}
icmp6src.sin6_flowinfo = (eip6->ip6_flow & IPV6_FLOWLABEL_MASK);
if (finaldst == NULL)
finaldst = &eip6->ip6_dst;
ip6cp.ip6c_m = m;
ip6cp.ip6c_icmp6 = icmp6;
ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
ip6cp.ip6c_off = eoff;
ip6cp.ip6c_finaldst = finaldst;
ip6cp.ip6c_src = &icmp6src;
ip6cp.ip6c_nxt = nxt;
if (icmp6type == ICMP6_PACKET_TOO_BIG) {
notifymtu = ntohl(icmp6->icmp6_mtu);
ip6cp.ip6c_cmdarg = (void *)&notifymtu;
icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/
}
ctlfunc = (void (*) __P((int, struct sockaddr *, void *)))
(inet6sw[ip6_protox[nxt]].pr_ctlinput);
if (ctlfunc) {
(void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst,
&ip6cp);
}
}
return (0);
freeit:
m_freem(m);
return (-1);
}
void
icmp6_mtudisc_update(ip6cp, validated)
struct ip6ctlparam *ip6cp;
int validated;
{
struct in6_addr *dst = ip6cp->ip6c_finaldst;
struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6;
struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */
u_int mtu = ntohl(icmp6->icmp6_mtu);
struct rtentry *rt = NULL;
struct sockaddr_in6 sin6;
#if 0
/*
* RFC2460 section 5, last paragraph.
* even though minimum link MTU for IPv6 is IPV6_MMTU,
* we may see ICMPv6 too big with mtu < IPV6_MMTU
* due to packet translator in the middle.
* see ip6_output() and ip6_getpmtu() "alwaysfrag" case for
* special handling.
*/
if (mtu < IPV6_MMTU)
return;
#endif
/*
* we reject ICMPv6 too big with abnormally small value.
* XXX what is the good definition of "abnormally small"?
*/
if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8)
return;
if (!validated)
return;
bzero(&sin6, sizeof(sin6));
sin6.sin6_family = PF_INET6;
sin6.sin6_len = sizeof(struct sockaddr_in6);
sin6.sin6_addr = *dst;
/* XXX normally, this won't happen */
if (IN6_IS_ADDR_LINKLOCAL(dst)) {
sin6.sin6_addr.s6_addr16[1] =
htons(m->m_pkthdr.rcvif->if_index);
}
/* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */
rt = rtalloc1((struct sockaddr *)&sin6, 0,
RTF_CLONING | RTF_PRCLONING);
if (rt && (rt->rt_flags & RTF_HOST) &&
!(rt->rt_rmx.rmx_locks & RTV_MTU)) {
if (mtu < IPV6_MMTU) {
/* xxx */
rt->rt_rmx.rmx_locks |= RTV_MTU;
} else if (mtu < rt->rt_ifp->if_mtu &&
rt->rt_rmx.rmx_mtu > mtu) {
icmp6stat.icp6s_pmtuchg++;
rt->rt_rmx.rmx_mtu = mtu;
}
}
if (rt)
rtfree(rt);
}
/*
* Process a Node Information Query packet, based on
* draft-ietf-ipngwg-icmp-name-lookups-07.
*
* Spec incompatibilities:
* - IPv6 Subject address handling
* - IPv4 Subject address handling support missing
* - Proxy reply (answer even if it's not for me)
* - joins NI group address at in6_ifattach() time only, does not cope
* with hostname changes by sethostname(3)
*/
#define hostnamelen strlen(hostname)
static struct mbuf *
ni6_input(m, off)
struct mbuf *m;
int off;
{
struct icmp6_nodeinfo *ni6, *nni6;
struct mbuf *n = NULL;
u_int16_t qtype;
int subjlen;
int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
struct ni_reply_fqdn *fqdn;
int addrs; /* for NI_QTYPE_NODEADDR */
struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */
struct sockaddr_in6 sin6_d; /* XXX: we should retrieve this from m_aux */
struct ip6_hdr *ip6;
int oldfqdn = 0; /* if 1, return pascal string (03 draft) */
char *subj = NULL;
struct in6_ifaddr *ia6 = NULL;
ip6 = mtod(m, struct ip6_hdr *);
#ifndef PULLDOWN_TEST
ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
#else
IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
if (ni6 == NULL) {
/* m is already reclaimed */
return (NULL);
}
#endif
/*
* Validate IPv6 destination address.
*
* The Responder must discard the Query without further processing
* unless it is one of the Responder's unicast or anycast addresses, or
* a link-local scope multicast address which the Responder has joined.
* [icmp-name-lookups-07, Section 4.]
*/
bzero(&sin6, sizeof(sin6));
sin6.sin6_family = AF_INET6;
sin6.sin6_len = sizeof(struct sockaddr_in6);
bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr));
/* XXX scopeid */
if ((ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)&sin6)) != NULL) {
/* unicast/anycast, fine */
if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
(icmp6_nodeinfo & 4) == 0) {
nd6log((LOG_DEBUG, "ni6_input: ignore node info to "
"a temporary address in %s:%d",
__FILE__, __LINE__));
goto bad;
}
} else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr))
; /* link-local multicast, fine */
else
goto bad;
/* validate query Subject field. */
qtype = ntohs(ni6->ni_qtype);
subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
switch (qtype) {
case NI_QTYPE_NOOP:
case NI_QTYPE_SUPTYPES:
/* 07 draft */
if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0)
break;
/* FALLTHROUGH */
case NI_QTYPE_FQDN:
case NI_QTYPE_NODEADDR:
switch (ni6->ni_code) {
case ICMP6_NI_SUBJ_IPV6:
#if ICMP6_NI_SUBJ_IPV6 != 0
case 0:
#endif
/*
* backward compatibility - try to accept 03 draft
* format, where no Subject is present.
*/
if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 &&
subjlen == 0) {
oldfqdn++;
break;
}
#if ICMP6_NI_SUBJ_IPV6 != 0
if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6)
goto bad;
#endif
if (subjlen != sizeof(sin6.sin6_addr))
goto bad;
/*
* Validate Subject address.
*
* Not sure what exactly "address belongs to the node"
* means in the spec, is it just unicast, or what?
*
* At this moment we consider Subject address as
* "belong to the node" if the Subject address equals
* to the IPv6 destination address; validation for
* IPv6 destination address should have done enough
* check for us.
*
* We do not do proxy at this moment.
*/
/* m_pulldown instead of copy? */
m_copydata(m, off + sizeof(struct icmp6_nodeinfo),
subjlen, (caddr_t)&sin6.sin6_addr);
if (in6_addr2zoneid(m->m_pkthdr.rcvif,
&sin6.sin6_addr, &sin6.sin6_scope_id)) {
goto bad;
}
in6_embedscope(&sin6.sin6_addr, &sin6, NULL, NULL);
bzero(&sin6_d, sizeof(sin6_d));
sin6_d.sin6_family = AF_INET6; /* not used, actually */
sin6_d.sin6_len = sizeof(sin6_d); /* ditto */
sin6_d.sin6_addr = ip6->ip6_dst;
if (in6_addr2zoneid(m->m_pkthdr.rcvif,
&ip6->ip6_dst, &sin6_d.sin6_scope_id)) {
goto bad;
}
in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL);
subj = (char *)&sin6;
if (SA6_ARE_ADDR_EQUAL(&sin6, &sin6_d))
break;
/*
* XXX if we are to allow other cases, we should really
* be careful about scope here.
* basically, we should disallow queries toward IPv6
* destination X with subject Y,
* if scope(X) > scope(Y).
* if we allow scope(X) > scope(Y), it will result in
* information leakage across scope boundary.
*/
goto bad;
case ICMP6_NI_SUBJ_FQDN:
/*
* Validate Subject name with gethostname(3).
*
* The behavior may need some debate, since:
* - we are not sure if the node has FQDN as
* hostname (returned by gethostname(3)).
* - the code does wildcard match for truncated names.
* however, we are not sure if we want to perform
* wildcard match, if gethostname(3) side has
* truncated hostname.
*/
n = ni6_nametodns(hostname, hostnamelen, 0);
if (!n || n->m_next || n->m_len == 0)
goto bad;
IP6_EXTHDR_GET(subj, char *, m,
off + sizeof(struct icmp6_nodeinfo), subjlen);
if (subj == NULL)
goto bad;
if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *),
n->m_len)) {
goto bad;
}
m_freem(n);
n = NULL;
break;
case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */
default:
goto bad;
}
break;
}
/* refuse based on configuration. XXX ICMP6_NI_REFUSED? */
switch (qtype) {
case NI_QTYPE_FQDN:
if ((icmp6_nodeinfo & 1) == 0)
goto bad;
break;
case NI_QTYPE_NODEADDR:
if ((icmp6_nodeinfo & 2) == 0)
goto bad;
break;
}
/* guess reply length */
switch (qtype) {
case NI_QTYPE_NOOP:
break; /* no reply data */
case NI_QTYPE_SUPTYPES:
replylen += sizeof(u_int32_t);
break;
case NI_QTYPE_FQDN:
/* XXX will append an mbuf */
replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
break;
case NI_QTYPE_NODEADDR:
addrs = ni6_addrs(ni6, m, &ifp, subj);
if ((replylen += addrs * (sizeof(struct in6_addr) +
sizeof(u_int32_t))) > MCLBYTES)
replylen = MCLBYTES; /* XXX: will truncate pkt later */
break;
default:
/*
* XXX: We must return a reply with the ICMP6 code
* `unknown Qtype' in this case. However we regard the case
* as an FQDN query for backward compatibility.
* Older versions set a random value to this field,
* so it rarely varies in the defined qtypes.
* But the mechanism is not reliable...
* maybe we should obsolete older versions.
*/
qtype = NI_QTYPE_FQDN;
/* XXX will append an mbuf */
replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
oldfqdn++;
break;
}
/* allocate an mbuf to reply. */
MGETHDR(n, M_DONTWAIT, m->m_type);
if (n == NULL) {
m_freem(m);
return (NULL);
}
M_MOVE_PKTHDR(n, m); /* just for recvif */
if (replylen > MHLEN) {
if (replylen > MCLBYTES) {
/*
* XXX: should we try to allocate more? But MCLBYTES
* is probably much larger than IPV6_MMTU...
*/
goto bad;
}
MCLGET(n, M_DONTWAIT);
if ((n->m_flags & M_EXT) == 0) {
goto bad;
}
}
n->m_pkthdr.len = n->m_len = replylen;
/* copy mbuf header and IPv6 + Node Information base headers */
bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
/* qtype dependent procedure */
switch (qtype) {
case NI_QTYPE_NOOP:
nni6->ni_code = ICMP6_NI_SUCCESS;
nni6->ni_flags = 0;
break;
case NI_QTYPE_SUPTYPES:
{
u_int32_t v;
nni6->ni_code = ICMP6_NI_SUCCESS;
nni6->ni_flags = htons(0x0000); /* raw bitmap */
/* supports NOOP, SUPTYPES, FQDN, and NODEADDR */
v = (u_int32_t)htonl(0x0000000f);
bcopy(&v, nni6 + 1, sizeof(u_int32_t));
break;
}
case NI_QTYPE_FQDN:
nni6->ni_code = ICMP6_NI_SUCCESS;
fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo));
nni6->ni_flags = 0; /* XXX: meaningless TTL */
fqdn->ni_fqdn_ttl = 0; /* ditto. */
/*
* XXX do we really have FQDN in variable "hostname"?
*/
n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn);
if (n->m_next == NULL)
goto bad;
/* XXX we assume that n->m_next is not a chain */
if (n->m_next->m_next != NULL)
goto bad;
n->m_pkthdr.len += n->m_next->m_len;
break;
case NI_QTYPE_NODEADDR:
{
int lenlim, copied;
nni6->ni_code = ICMP6_NI_SUCCESS;
n->m_pkthdr.len = n->m_len =
sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
lenlim = M_TRAILINGSPACE(n);
copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
/* XXX: reset mbuf length */
n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
sizeof(struct icmp6_nodeinfo) + copied;
break;
}
default:
break; /* XXX impossible! */
}
nni6->ni_type = ICMP6_NI_REPLY;
m_freem(m);
return (n);
bad:
m_freem(m);
if (n)
m_freem(n);
return (NULL);
}
#undef hostnamelen
/*
* make a mbuf with DNS-encoded string. no compression support.
*
* XXX names with less than 2 dots (like "foo" or "foo.section") will be
* treated as truncated name (two \0 at the end). this is a wild guess.
*/
static struct mbuf *
ni6_nametodns(name, namelen, old)
const char *name;
int namelen;
int old; /* return pascal string if non-zero */
{
struct mbuf *m;
char *cp, *ep;
const char *p, *q;
int i, len, nterm;
if (old)
len = namelen + 1;
else
len = MCLBYTES;
/* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */
MGET(m, M_DONTWAIT, MT_DATA);
if (m && len > MLEN) {
MCLGET(m, M_DONTWAIT);
if ((m->m_flags & M_EXT) == 0)
goto fail;
}
if (!m)
goto fail;
m->m_next = NULL;
if (old) {
m->m_len = len;
*mtod(m, char *) = namelen;
bcopy(name, mtod(m, char *) + 1, namelen);
return m;
} else {
m->m_len = 0;
cp = mtod(m, char *);
ep = mtod(m, char *) + M_TRAILINGSPACE(m);
/* if not certain about my name, return empty buffer */
if (namelen == 0)
return m;
/*
* guess if it looks like shortened hostname, or FQDN.
* shortened hostname needs two trailing "\0".
*/
i = 0;
for (p = name; p < name + namelen; p++) {
if (*p && *p == '.')
i++;
}
if (i < 2)
nterm = 2;
else
nterm = 1;
p = name;
while (cp < ep && p < name + namelen) {
i = 0;
for (q = p; q < name + namelen && *q && *q != '.'; q++)
i++;
/* result does not fit into mbuf */
if (cp + i + 1 >= ep)
goto fail;
/*
* DNS label length restriction, RFC1035 page 8.
* "i == 0" case is included here to avoid returning
* 0-length label on "foo..bar".
*/
if (i <= 0 || i >= 64)
goto fail;
*cp++ = i;
bcopy(p, cp, i);
cp += i;
p = q;
if (p < name + namelen && *p == '.')
p++;
}
/* termination */
if (cp + nterm >= ep)
goto fail;
while (nterm-- > 0)
*cp++ = '\0';
m->m_len = cp - mtod(m, char *);
return m;
}
panic("should not reach here");
/* NOTREACHED */
fail:
if (m)
m_freem(m);
return NULL;
}
/*
* check if two DNS-encoded string matches. takes care of truncated
* form (with \0\0 at the end). no compression support.
* XXX upper/lowercase match (see RFC2065)
*/
static int
ni6_dnsmatch(a, alen, b, blen)
const char *a;
int alen;
const char *b;
int blen;
{
const char *a0, *b0;
int l;
/* simplest case - need validation? */
if (alen == blen && bcmp(a, b, alen) == 0)
return 1;
a0 = a;
b0 = b;
/* termination is mandatory */
if (alen < 2 || blen < 2)
return 0;
if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0')
return 0;
alen--;
blen--;
while (a - a0 < alen && b - b0 < blen) {
if (a - a0 + 1 > alen || b - b0 + 1 > blen)
return 0;
if ((signed char)a[0] < 0 || (signed char)b[0] < 0)
return 0;
/* we don't support compression yet */
if (a[0] >= 64 || b[0] >= 64)
return 0;
/* truncated case */
if (a[0] == 0 && a - a0 == alen - 1)
return 1;
if (b[0] == 0 && b - b0 == blen - 1)
return 1;
if (a[0] == 0 || b[0] == 0)
return 0;
if (a[0] != b[0])
return 0;
l = a[0];
if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen)
return 0;
if (bcmp(a + 1, b + 1, l) != 0)
return 0;
a += 1 + l;
b += 1 + l;
}
if (a - a0 == alen && b - b0 == blen)
return 1;
else
return 0;
}
/*
* calculate the number of addresses to be returned in the node info reply.
*/
static int
ni6_addrs(ni6, m, ifpp, subj)
struct icmp6_nodeinfo *ni6;
struct mbuf *m;
struct ifnet **ifpp;
char *subj;
{
struct ifnet *ifp;
struct in6_ifaddr *ifa6;
struct ifaddr *ifa;
struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */
int addrs = 0, addrsofif, iffound = 0;
int niflags = ni6->ni_flags;
if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) {
switch (ni6->ni_code) {
case ICMP6_NI_SUBJ_IPV6:
if (subj == NULL) /* must be impossible... */
return (0);
subj_ip6 = (struct sockaddr_in6 *)subj;
break;
default:
/*
* XXX: we only support IPv6 subject address for
* this Qtype.
*/
return (0);
}
}
IFNET_RLOCK();
for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
addrsofif = 0;
TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
if (ifa->ifa_addr->sa_family != AF_INET6)
continue;
ifa6 = (struct in6_ifaddr *)ifa;
if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 &&
IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr,
&ifa6->ia_addr.sin6_addr))
iffound = 1;
/*
* IPv4-mapped addresses can only be returned by a
* Node Information proxy, since they represent
* addresses of IPv4-only nodes, which perforce do
* not implement this protocol.
* [icmp-name-lookups-07, Section 5.4]
* So we don't support NI_NODEADDR_FLAG_COMPAT in
* this function at this moment.
*/
/* What do we have to do about ::1? */
switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
case IPV6_ADDR_SCOPE_LINKLOCAL:
if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
continue;
break;
case IPV6_ADDR_SCOPE_SITELOCAL:
if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
continue;
break;
case IPV6_ADDR_SCOPE_GLOBAL:
if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
continue;
break;
default:
continue;
}
/*
* check if anycast is okay.
* XXX: just experimental. not in the spec.
*/
if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
(niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
continue; /* we need only unicast addresses */
if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
(icmp6_nodeinfo & 4) == 0) {
continue;
}
addrsofif++; /* count the address */
}
if (iffound) {
*ifpp = ifp;
IFNET_RUNLOCK();
return (addrsofif);
}
addrs += addrsofif;
}
IFNET_RUNLOCK();
return (addrs);
}
static int
ni6_store_addrs(ni6, nni6, ifp0, resid)
struct icmp6_nodeinfo *ni6, *nni6;
struct ifnet *ifp0;
int resid;
{
struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet);
struct in6_ifaddr *ifa6;
struct ifaddr *ifa;
struct ifnet *ifp_dep = NULL;
int copied = 0, allow_deprecated = 0;
u_char *cp = (u_char *)(nni6 + 1);
int niflags = ni6->ni_flags;
u_int32_t ltime;
if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL))
return (0); /* needless to copy */
IFNET_RLOCK();
again:
for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
for (ifa = ifp->if_addrlist.tqh_first; ifa;
ifa = ifa->ifa_list.tqe_next) {
if (ifa->ifa_addr->sa_family != AF_INET6)
continue;
ifa6 = (struct in6_ifaddr *)ifa;
if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 &&
allow_deprecated == 0) {
/*
* prefererred address should be put before
* deprecated addresses.
*/
/* record the interface for later search */
if (ifp_dep == NULL)
ifp_dep = ifp;
continue;
} else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 &&
allow_deprecated != 0)
continue; /* we now collect deprecated addrs */
/* What do we have to do about ::1? */
switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
case IPV6_ADDR_SCOPE_LINKLOCAL:
if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
continue;
break;
case IPV6_ADDR_SCOPE_SITELOCAL:
if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
continue;
break;
case IPV6_ADDR_SCOPE_GLOBAL:
if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
continue;
break;
default:
continue;
}
/*
* check if anycast is okay.
* XXX: just experimental. not in the spec.
*/
if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
(niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
continue;
if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 &&
(icmp6_nodeinfo & 4) == 0) {
continue;
}
/* now we can copy the address */
if (resid < sizeof(struct in6_addr) +
sizeof(u_int32_t)) {
/*
* We give up much more copy.
* Set the truncate flag and return.
*/
nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE;
IFNET_RUNLOCK();
return (copied);
}
/*
* Set the TTL of the address.
* The TTL value should be one of the following
* according to the specification:
*
* 1. The remaining lifetime of a DHCP lease on the
* address, or
* 2. The remaining Valid Lifetime of a prefix from
* which the address was derived through Stateless
* Autoconfiguration.
*
* Note that we currently do not support stateful
* address configuration by DHCPv6, so the former
* case can't happen.
*/
if (ifa6->ia6_lifetime.ia6t_expire == 0)
ltime = ND6_INFINITE_LIFETIME;
else {
if (ifa6->ia6_lifetime.ia6t_expire >
time_second)
ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second);
else
ltime = 0;
}
bcopy(&ltime, cp, sizeof(u_int32_t));
cp += sizeof(u_int32_t);
/* copy the address itself */
bcopy(&ifa6->ia_addr.sin6_addr, cp,
sizeof(struct in6_addr));
in6_clearscope((struct in6_addr *)cp); /* XXX */
cp += sizeof(struct in6_addr);
resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t));
copied += (sizeof(struct in6_addr) + sizeof(u_int32_t));
}
if (ifp0) /* we need search only on the specified IF */
break;
}
if (allow_deprecated == 0 && ifp_dep != NULL) {
ifp = ifp_dep;
allow_deprecated = 1;
goto again;
}
IFNET_RUNLOCK();
return (copied);
}
/*
* XXX almost dup'ed code with rip6_input.
*/
static int
icmp6_rip6_input(mp, off)
struct mbuf **mp;
int off;
{
struct mbuf *m = *mp;
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct in6pcb *in6p;
struct in6pcb *last = NULL;
struct sockaddr_in6 fromsa;
struct icmp6_hdr *icmp6;
struct mbuf *opts = NULL;
#ifndef PULLDOWN_TEST
/* this is assumed to be safe. */
icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
#else
IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
if (icmp6 == NULL) {
/* m is already reclaimed */
return (IPPROTO_DONE);
}
#endif
bzero(&fromsa, sizeof(fromsa));
fromsa.sin6_len = sizeof(struct sockaddr_in6);
fromsa.sin6_family = AF_INET6;
/* KAME hack: recover scopeid */
(void)in6_recoverscope(&fromsa, &ip6->ip6_src, m->m_pkthdr.rcvif);
LIST_FOREACH(in6p, &ripcb, inp_list) {
if ((in6p->inp_vflag & INP_IPV6) == 0)
continue;
if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6)
continue;
if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
!IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
continue;
if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
continue;
if (in6p->in6p_icmp6filt
&& ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
in6p->in6p_icmp6filt))
continue;
if (last) {
struct mbuf *n;
if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
if (last->in6p_flags & IN6P_CONTROLOPTS)
ip6_savecontrol(last, &opts, ip6, n);
/* strip intermediate headers */
m_adj(n, off);
if (sbappendaddr(&last->in6p_socket->so_rcv,
(struct sockaddr *)&fromsa, n, opts)
== 0) {
/* should notify about lost packet */
m_freem(n);
if (opts) {
m_freem(opts);
}
} else
sorwakeup(last->in6p_socket);
opts = NULL;
}
}
last = in6p;
}
if (last) {
if (last->in6p_flags & IN6P_CONTROLOPTS)
ip6_savecontrol(last, &opts, ip6, m);
/* strip intermediate headers */
m_adj(m, off);
if (sbappendaddr(&last->in6p_socket->so_rcv,
(struct sockaddr *)&fromsa, m, opts) == 0) {
m_freem(m);
if (opts)
m_freem(opts);
} else
sorwakeup(last->in6p_socket);
} else {
m_freem(m);
ip6stat.ip6s_delivered--;
}
return IPPROTO_DONE;
}
/*
* Reflect the ip6 packet back to the source.
* OFF points to the icmp6 header, counted from the top of the mbuf.
*/
void
icmp6_reflect(m, off)
struct mbuf *m;
size_t off;
{
struct ip6_hdr *ip6;
struct icmp6_hdr *icmp6;
struct in6_ifaddr *ia;
struct in6_addr t, *src = 0;
int plen;
int type, code;
struct ifnet *outif = NULL;
struct sockaddr_in6 sa6_src, sa6_dst;
#ifdef COMPAT_RFC1885
int mtu = IPV6_MMTU;
struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst;
#endif
/* too short to reflect */
if (off < sizeof(struct ip6_hdr)) {
nd6log((LOG_DEBUG,
"sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
(u_long)off, (u_long)sizeof(struct ip6_hdr),
__FILE__, __LINE__));
goto bad;
}
/*
* If there are extra headers between IPv6 and ICMPv6, strip
* off that header first.
*/
#ifdef DIAGNOSTIC
if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN)
panic("assumption failed in icmp6_reflect");
#endif
if (off > sizeof(struct ip6_hdr)) {
size_t l;
struct ip6_hdr nip6;
l = off - sizeof(struct ip6_hdr);
m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
m_adj(m, l);
l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
if (m->m_len < l) {
if ((m = m_pullup(m, l)) == NULL)
return;
}
bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
} else /* off == sizeof(struct ip6_hdr) */ {
size_t l;
l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
if (m->m_len < l) {
if ((m = m_pullup(m, l)) == NULL)
return;
}
}
plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_nxt = IPPROTO_ICMPV6;
icmp6 = (struct icmp6_hdr *)(ip6 + 1);
type = icmp6->icmp6_type; /* keep type for statistics */
code = icmp6->icmp6_code; /* ditto. */
t = ip6->ip6_dst;
/*
* ip6_input() drops a packet if its src is multicast.
* So, the src is never multicast.
*/
ip6->ip6_dst = ip6->ip6_src;
/*
* XXX: make sure to embed scope zone information, using
* already embedded IDs or the received interface (if any).
* Note that rcvif may be NULL.
* TODO: scoped routing case (XXX).
*/
bzero(&sa6_src, sizeof(sa6_src));
sa6_src.sin6_family = AF_INET6;
sa6_src.sin6_len = sizeof(sa6_src);
sa6_src.sin6_addr = ip6->ip6_dst;
in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif);
in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL);
bzero(&sa6_dst, sizeof(sa6_dst));
sa6_dst.sin6_family = AF_INET6;
sa6_dst.sin6_len = sizeof(sa6_dst);
sa6_dst.sin6_addr = t;
in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif);
in6_embedscope(&t, &sa6_dst, NULL, NULL);
#ifdef COMPAT_RFC1885
/*
* xxx guess MTU
* RFC 1885 requires that echo reply should be truncated if it
* does not fit in with (return) path MTU, but the description was
* removed in the new spec.
*/
if (icmp6_reflect_rt.ro_rt == 0 ||
! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) {
if (icmp6_reflect_rt.ro_rt) {
RTFREE(icmp6_reflect_rt.ro_rt);
icmp6_reflect_rt.ro_rt = 0;
}
bzero(sin6, sizeof(*sin6));
sin6->sin6_family = PF_INET6;
sin6->sin6_len = sizeof(struct sockaddr_in6);
sin6->sin6_addr = ip6->ip6_dst;
rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt,
RTF_PRCLONING);
}
if (icmp6_reflect_rt.ro_rt == 0)
goto bad;
if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST)
&& mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu)
mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu;
if (mtu < m->m_pkthdr.len) {
plen -= (m->m_pkthdr.len - mtu);
m_adj(m, mtu - m->m_pkthdr.len);
}
#endif
/*
* If the incoming packet was addressed directly to us (i.e. unicast),
* use dst as the src for the reply.
* The IN6_IFF_NOTREADY case should be VERY rare, but is possible
* (for example) when we encounter an error while forwarding procedure
* destined to a duplicated address of ours.
*/
for (ia = in6_ifaddr; ia; ia = ia->ia_next)
if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) &&
(ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) {
src = &t;
break;
}
if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) {
/*
* This is the case if the dst is our link-local address
* and the sender is also ourselves.
*/
src = &t;
}
if (src == 0) {
int e;
struct route_in6 ro;
/*
* This case matches to multicasts, our anycast, or unicasts
* that we do not own. Select a source address based on the
* source address of the erroneous packet.
*/
bzero(&ro, sizeof(ro));
src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e);
if (ro.ro_rt)
RTFREE(ro.ro_rt); /* XXX: we could use this */
if (src == NULL) {
nd6log((LOG_DEBUG,
"icmp6_reflect: source can't be determined: "
"dst=%s, error=%d\n",
ip6_sprintf(&sa6_src.sin6_addr), e));
goto bad;
}
}
ip6->ip6_src = *src;
ip6->ip6_flow = 0;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
ip6->ip6_nxt = IPPROTO_ICMPV6;
if (outif)
ip6->ip6_hlim = ND_IFINFO(outif)->chlim;
else if (m->m_pkthdr.rcvif) {
/* XXX: This may not be the outgoing interface */
ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim;
} else
ip6->ip6_hlim = ip6_defhlim;
icmp6->icmp6_cksum = 0;
icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
sizeof(struct ip6_hdr), plen);
/*
* XXX option handling
*/
m->m_flags &= ~(M_BCAST|M_MCAST);
#ifdef COMPAT_RFC1885
ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL);
#else
ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
#endif
if (outif)
icmp6_ifoutstat_inc(outif, type, code);
return;
bad:
m_freem(m);
return;
}
void
icmp6_fasttimo()
{
mld6_fasttimeo();
}
static const char *
icmp6_redirect_diag(src6, dst6, tgt6)
struct in6_addr *src6;
struct in6_addr *dst6;
struct in6_addr *tgt6;
{
static char buf[1024];
snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6));
return buf;
}
void
icmp6_redirect_input(m, off)
struct mbuf *m;
int off;
{
struct ifnet *ifp = m->m_pkthdr.rcvif;
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct nd_redirect *nd_rd;
int icmp6len = ntohs(ip6->ip6_plen);
char *lladdr = NULL;
int lladdrlen = 0;
u_char *redirhdr = NULL;
int redirhdrlen = 0;
struct rtentry *rt = NULL;
int is_router;
int is_onlink;
struct in6_addr src6 = ip6->ip6_src;
struct in6_addr redtgt6;
struct in6_addr reddst6;
union nd_opts ndopts;
if (!m || !ifp)
return;
/* XXX if we are router, we don't update route by icmp6 redirect */
if (ip6_forwarding)
goto freeit;
if (!icmp6_rediraccept)
goto freeit;
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, icmp6len,);
nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
#else
IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len);
if (nd_rd == NULL) {
icmp6stat.icp6s_tooshort++;
return;
}
#endif
redtgt6 = nd_rd->nd_rd_target;
reddst6 = nd_rd->nd_rd_dst;
if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
redtgt6.s6_addr16[1] = htons(ifp->if_index);
if (IN6_IS_ADDR_LINKLOCAL(&reddst6))
reddst6.s6_addr16[1] = htons(ifp->if_index);
/* validation */
if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
nd6log((LOG_ERR,
"ICMP6 redirect sent from %s rejected; "
"must be from linklocal\n",
ip6_sprintf(&src6)));
goto bad;
}
if (ip6->ip6_hlim != 255) {
nd6log((LOG_ERR,
"ICMP6 redirect sent from %s rejected; "
"hlim=%d (must be 255)\n",
ip6_sprintf(&src6), ip6->ip6_hlim));
goto bad;
}
{
/* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
struct sockaddr_in6 sin6;
struct in6_addr *gw6;
bzero(&sin6, sizeof(sin6));
sin6.sin6_family = AF_INET6;
sin6.sin6_len = sizeof(struct sockaddr_in6);
bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6));
rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL);
if (rt) {
if (rt->rt_gateway == NULL ||
rt->rt_gateway->sa_family != AF_INET6) {
nd6log((LOG_ERR,
"ICMP6 redirect rejected; no route "
"with inet6 gateway found for redirect dst: %s\n",
icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
RTFREE_LOCKED(rt);
goto bad;
}
gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
nd6log((LOG_ERR,
"ICMP6 redirect rejected; "
"not equal to gw-for-src=%s (must be same): "
"%s\n",
ip6_sprintf(gw6),
icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
RTFREE_LOCKED(rt);
goto bad;
}
} else {
nd6log((LOG_ERR,
"ICMP6 redirect rejected; "
"no route found for redirect dst: %s\n",
icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
goto bad;
}
RTFREE_LOCKED(rt);
rt = NULL;
}
if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
nd6log((LOG_ERR,
"ICMP6 redirect rejected; "
"redirect dst must be unicast: %s\n",
icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
goto bad;
}
is_router = is_onlink = 0;
if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
is_router = 1; /* router case */
if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
is_onlink = 1; /* on-link destination case */
if (!is_router && !is_onlink) {
nd6log((LOG_ERR,
"ICMP6 redirect rejected; "
"neither router case nor onlink case: %s\n",
icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
goto bad;
}
/* validation passed */
icmp6len -= sizeof(*nd_rd);
nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
if (nd6_options(&ndopts) < 0) {
nd6log((LOG_INFO, "icmp6_redirect_input: "
"invalid ND option, rejected: %s\n",
icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
/* nd6_options have incremented stats */
goto freeit;
}
if (ndopts.nd_opts_tgt_lladdr) {
lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
}
if (ndopts.nd_opts_rh) {
redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len;
redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */
}
if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
nd6log((LOG_INFO,
"icmp6_redirect_input: lladdrlen mismatch for %s "
"(if %d, icmp6 packet %d): %s\n",
ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2,
icmp6_redirect_diag(&src6, &reddst6, &redtgt6)));
goto bad;
}
/* RFC 2461 8.3 */
nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
if (!is_onlink) { /* better router case. perform rtredirect. */
/* perform rtredirect */
struct sockaddr_in6 sdst;
struct sockaddr_in6 sgw;
struct sockaddr_in6 ssrc;
bzero(&sdst, sizeof(sdst));
bzero(&sgw, sizeof(sgw));
bzero(&ssrc, sizeof(ssrc));
sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
sizeof(struct sockaddr_in6);
bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw,
(struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST,
(struct sockaddr *)&ssrc);
}
/* finally update cached route in each socket via pfctlinput */
{
struct sockaddr_in6 sdst;
bzero(&sdst, sizeof(sdst));
sdst.sin6_family = AF_INET6;
sdst.sin6_len = sizeof(struct sockaddr_in6);
bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
#ifdef IPSEC
key_sa_routechange((struct sockaddr *)&sdst);
#endif
}
freeit:
m_freem(m);
return;
bad:
icmp6stat.icp6s_badredirect++;
m_freem(m);
}
void
icmp6_redirect_output(m0, rt)
struct mbuf *m0;
struct rtentry *rt;
{
struct ifnet *ifp; /* my outgoing interface */
struct in6_addr *ifp_ll6;
struct in6_addr *router_ll6;
struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */
struct mbuf *m = NULL; /* newly allocated one */
struct ip6_hdr *ip6; /* m as struct ip6_hdr */
struct nd_redirect *nd_rd;
size_t maxlen;
u_char *p;
struct ifnet *outif = NULL;
struct sockaddr_in6 src_sa;
icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0);
/* if we are not router, we don't send icmp6 redirect */
if (!ip6_forwarding || ip6_accept_rtadv)
goto fail;
/* sanity check */
if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp))
goto fail;
/*
* Address check:
* the source address must identify a neighbor, and
* the destination address must not be a multicast address
* [RFC 2461, sec 8.2]
*/
sip6 = mtod(m0, struct ip6_hdr *);
bzero(&src_sa, sizeof(src_sa));
src_sa.sin6_family = AF_INET6;
src_sa.sin6_len = sizeof(src_sa);
src_sa.sin6_addr = sip6->ip6_src;
/* we don't currently use sin6_scope_id, but eventually use it */
if (in6_addr2zoneid(ifp, &sip6->ip6_src, &src_sa.sin6_scope_id))
goto fail;
if (nd6_is_addr_neighbor(&src_sa, ifp) == 0)
goto fail;
if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
goto fail; /* what should we do here? */
/* rate limit */
if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
goto fail;
/*
* Since we are going to append up to 1280 bytes (= IPV6_MMTU),
* we almost always ask for an mbuf cluster for simplicity.
* (MHLEN < IPV6_MMTU is almost always true)
*/
#if IPV6_MMTU >= MCLBYTES
# error assumption failed about IPV6_MMTU and MCLBYTES
#endif
MGETHDR(m, M_DONTWAIT, MT_HEADER);
if (m && IPV6_MMTU >= MHLEN)
MCLGET(m, M_DONTWAIT);
if (!m)
goto fail;
m->m_pkthdr.rcvif = NULL;
m->m_len = 0;
maxlen = M_TRAILINGSPACE(m);
maxlen = min(IPV6_MMTU, maxlen);
/* just for safety */
if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) +
((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) {
goto fail;
}
{
/* get ip6 linklocal address for ifp(my outgoing interface). */
struct in6_ifaddr *ia;
if ((ia = in6ifa_ifpforlinklocal(ifp,
IN6_IFF_NOTREADY|
IN6_IFF_ANYCAST)) == NULL)
goto fail;
ifp_ll6 = &ia->ia_addr.sin6_addr;
}
/* get ip6 linklocal address for the router. */
if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
struct sockaddr_in6 *sin6;
sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
router_ll6 = &sin6->sin6_addr;
if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
router_ll6 = (struct in6_addr *)NULL;
} else
router_ll6 = (struct in6_addr *)NULL;
/* ip6 */
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_flow = 0;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
/* ip6->ip6_plen will be set later */
ip6->ip6_nxt = IPPROTO_ICMPV6;
ip6->ip6_hlim = 255;
/* ip6->ip6_src must be linklocal addr for my outgoing if. */
bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
/* ND Redirect */
nd_rd = (struct nd_redirect *)(ip6 + 1);
nd_rd->nd_rd_type = ND_REDIRECT;
nd_rd->nd_rd_code = 0;
nd_rd->nd_rd_reserved = 0;
if (rt->rt_flags & RTF_GATEWAY) {
/*
* nd_rd->nd_rd_target must be a link-local address in
* better router cases.
*/
if (!router_ll6)
goto fail;
bcopy(router_ll6, &nd_rd->nd_rd_target,
sizeof(nd_rd->nd_rd_target));
bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
sizeof(nd_rd->nd_rd_dst));
} else {
/* make sure redtgt == reddst */
bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
sizeof(nd_rd->nd_rd_target));
bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
sizeof(nd_rd->nd_rd_dst));
}
p = (u_char *)(nd_rd + 1);
if (!router_ll6)
goto nolladdropt;
{
/* target lladdr option */
struct rtentry *rt_router = NULL;
int len;
struct sockaddr_dl *sdl;
struct nd_opt_hdr *nd_opt;
char *lladdr;
rt_router = nd6_lookup(router_ll6, 0, ifp);
if (!rt_router)
goto nolladdropt;
len = sizeof(*nd_opt) + ifp->if_addrlen;
len = (len + 7) & ~7; /* round by 8 */
/* safety check */
if (len + (p - (u_char *)ip6) > maxlen)
goto nolladdropt;
if (!(rt_router->rt_flags & RTF_GATEWAY) &&
(rt_router->rt_flags & RTF_LLINFO) &&
(rt_router->rt_gateway->sa_family == AF_LINK) &&
(sdl = (struct sockaddr_dl *)rt_router->rt_gateway) &&
sdl->sdl_alen) {
nd_opt = (struct nd_opt_hdr *)p;
nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
nd_opt->nd_opt_len = len >> 3;
lladdr = (char *)(nd_opt + 1);
bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen);
p += len;
}
}
nolladdropt:;
m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
/* just to be safe */
#ifdef M_DECRYPTED /*not openbsd*/
if (m0->m_flags & M_DECRYPTED)
goto noredhdropt;
#endif
if (p - (u_char *)ip6 > maxlen)
goto noredhdropt;
{
/* redirected header option */
int len;
struct nd_opt_rd_hdr *nd_opt_rh;
/*
* compute the maximum size for icmp6 redirect header option.
* XXX room for auth header?
*/
len = maxlen - (p - (u_char *)ip6);
len &= ~7;
/* This is just for simplicity. */
if (m0->m_pkthdr.len != m0->m_len) {
if (m0->m_next) {
m_freem(m0->m_next);
m0->m_next = NULL;
}
m0->m_pkthdr.len = m0->m_len;
}
/*
* Redirected header option spec (RFC2461 4.6.3) talks nothing
* about padding/truncate rule for the original IP packet.
* From the discussion on IPv6imp in Feb 1999,
* the consensus was:
* - "attach as much as possible" is the goal
* - pad if not aligned (original size can be guessed by
* original ip6 header)
* Following code adds the padding if it is simple enough,
* and truncates if not.
*/
if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
panic("assumption failed in %s:%d", __FILE__,
__LINE__);
if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
/* not enough room, truncate */
m0->m_pkthdr.len = m0->m_len = len -
sizeof(*nd_opt_rh);
} else {
/* enough room, pad or truncate */
size_t extra;
extra = m0->m_pkthdr.len % 8;
if (extra) {
/* pad if easy enough, truncate if not */
if (8 - extra <= M_TRAILINGSPACE(m0)) {
/* pad */
m0->m_len += (8 - extra);
m0->m_pkthdr.len += (8 - extra);
} else {
/* truncate */
m0->m_pkthdr.len -= extra;
m0->m_len -= extra;
}
}
len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
m0->m_pkthdr.len = m0->m_len = len -
sizeof(*nd_opt_rh);
}
nd_opt_rh = (struct nd_opt_rd_hdr *)p;
bzero(nd_opt_rh, sizeof(*nd_opt_rh));
nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
nd_opt_rh->nd_opt_rh_len = len >> 3;
p += sizeof(*nd_opt_rh);
m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
/* connect m0 to m */
m_tag_delete_chain(m0, NULL);
m0->m_flags &= ~M_PKTHDR;
m->m_next = m0;
m->m_pkthdr.len = m->m_len + m0->m_len;
m0 = NULL;
}
noredhdropt:;
if (m0) {
m_freem(m0);
m0 = NULL;
}
/* XXX: clear embedded link IDs in the inner header */
in6_clearscope(&sip6->ip6_src);
in6_clearscope(&sip6->ip6_dst);
in6_clearscope(&nd_rd->nd_rd_target);
in6_clearscope(&nd_rd->nd_rd_dst);
ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
nd_rd->nd_rd_cksum = 0;
nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6,
sizeof(*ip6), ntohs(ip6->ip6_plen));
/* send the packet to outside... */
ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL);
if (outif) {
icmp6_ifstat_inc(outif, ifs6_out_msg);
icmp6_ifstat_inc(outif, ifs6_out_redirect);
}
icmp6stat.icp6s_outhist[ND_REDIRECT]++;
return;
fail:
if (m)
m_freem(m);
if (m0)
m_freem(m0);
}
/*
* ICMPv6 socket option processing.
*/
int
icmp6_ctloutput(so, sopt)
struct socket *so;
struct sockopt *sopt;
{
int error = 0;
int optlen;
struct inpcb *inp = sotoinpcb(so);
int level, op, optname;
if (sopt) {
level = sopt->sopt_level;
op = sopt->sopt_dir;
optname = sopt->sopt_name;
optlen = sopt->sopt_valsize;
} else
level = op = optname = optlen = 0;
if (level != IPPROTO_ICMPV6) {
return EINVAL;
}
switch (op) {
case PRCO_SETOPT:
switch (optname) {
case ICMP6_FILTER:
{
struct icmp6_filter *p;
if (optlen != sizeof(*p)) {
error = EMSGSIZE;
break;
}
if (inp->in6p_icmp6filt == NULL) {
error = EINVAL;
break;
}
error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen,
optlen);
break;
}
default:
error = ENOPROTOOPT;
break;
}
break;
case PRCO_GETOPT:
switch (optname) {
case ICMP6_FILTER:
{
if (inp->in6p_icmp6filt == NULL) {
error = EINVAL;
break;
}
error = sooptcopyout(sopt, inp->in6p_icmp6filt,
sizeof(struct icmp6_filter));
break;
}
default:
error = ENOPROTOOPT;
break;
}
break;
}
return (error);
}
/*
* Perform rate limit check.
* Returns 0 if it is okay to send the icmp6 packet.
* Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
* limitation.
*
* XXX per-destination/type check necessary?
*/
static int
icmp6_ratelimit(dst, type, code)
const struct in6_addr *dst; /* not used at this moment */
const int type; /* not used at this moment */
const int code; /* not used at this moment */
{
int ret;
ret = 0; /* okay to send */
/* PPS limit */
if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count,
icmp6errppslim)) {
/* The packet is subject to rate limit */
ret++;
}
return ret;
}
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