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freebsd-dev/sys/netinet6/icmp6.c
itojun 7babc58a35 sync with kame tree as of july00. tons of bug fixes/improvements. 
API changes:
- additional IPv6 ioctls
- IPsec PF_KEY API was changed, it is mandatory to upgrade setkey(8).
  (also syntax change)
2000-07-04 16:35:15 +00:00

2607 lines
66 KiB
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/* $FreeBSD$ */
/* $KAME: icmp6.c,v 1.119 2000/07/03 14:16:46 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/systm.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 <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 <netinet/icmp6.h>
#include <netinet6/mld6_var.h>
#include <netinet/in_pcb.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/nd6.h>
#include <netinet6/in6_ifattach.h>
#include <netinet6/ip6protosw.h>
#ifdef IPSEC
#include <netinet6/ipsec.h>
#ifdef INET6
#include <netinet6/ipsec6.h>
#endif
#include <netkey/key.h>
#endif
#include "faith.h"
#include <net/net_osdep.h>
extern struct domain inet6domain;
extern struct ip6protosw inet6sw[];
extern u_char ip6_protox[];
struct icmp6stat icmp6stat;
extern struct inpcbhead ripcb;
extern struct timeval icmp6errratelim;
static struct timeval icmp6errratelim_last;
extern int icmp6errppslim;
static int icmp6errpps_count = 0;
extern int icmp6_nodeinfo;
static void icmp6_errcount __P((struct icmp6errstat *, int, int));
static int icmp6_rip6_input __P((struct mbuf **, int));
static void icmp6_mtudisc_update __P((struct in6_addr *, struct icmp6_hdr *,
struct mbuf *));
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 *));
#ifndef HAVE_RATECHECK
static int ratecheck __P((struct timeval *, struct timeval *));
#endif
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 **));
static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
struct ifnet *, 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 *);
/*
* Multicast destination check. For unrecognized option errors,
* this check has already done in ip6_unknown_opt(), so we can
* check only for other errors.
*/
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;
/* 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) {
printf("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;
if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src))
oip6->ip6_src.s6_addr16[1] = 0;
if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst))
oip6->ip6_dst.s6_addr16[1] = 0;
icmp6 = (struct icmp6_hdr *)(nip6 + 1);
icmp6->icmp6_type = type;
icmp6->icmp6_code = code;
icmp6->icmp6_pptr = htonl((u_int32_t)param);
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;
struct sockaddr_in6 icmp6src;
#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) {
log(LOG_ERR,
"ICMP6 checksum error(%d|%x) %s\n",
icmp6->icmp6_type,
sum,
ip6_sprintf(&ip6->ip6_src));
icmp6stat.icp6s_checksum++;
goto freeit;
}
#if defined(NFAITH) && 0 < NFAITH
if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type == IFT_FAITH) {
/*
* 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;
}
}
#endif
#ifdef IPSEC
/* drop it if it does not match the default policy */
if (ipsec6_in_reject(m, NULL)) {
ipsecstat.in_polvio++;
goto freeit;
}
#endif
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);
/*
* Prepare an internal mbuf. m_pullup() doesn't
* always copy the length we specified.
*/
if (maxlen >= MCLBYTES) {
#ifdef DIAGNOSTIC
printf("MCLBYTES too small\n");
#endif
/* Give up remote */
m_freem(n0);
break;
}
MGETHDR(n, M_DONTWAIT, n0->m_type);
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;
}
M_COPY_PKTHDR(n, n0);
/*
* 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);
n->m_pkthdr.len = 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));
n->m_pkthdr.len += n0->m_pkthdr.len;
n->m_next = n0;
n0->m_flags &= ~M_PKTHDR;
} 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 MLD6_LISTENER_QUERY:
case MLD6_LISTENER_REPORT:
if (icmp6len < sizeof(struct mld6_hdr))
goto badlen;
if (icmp6->icmp6_type == MLD6_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 MLD6_LISTENER_DONE:
icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone);
if (icmp6len < sizeof(struct mld6_hdr)) /* necessary? */
goto badlen;
break; /* nothing to be done in kernel */
case MLD6_MTRACE_RESP:
case MLD6_MTRACE:
/* XXX: these two are experimental. not officially defind. */
/* 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 (code != 0)
goto badcode;
maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4;
if (maxlen >= MCLBYTES) {
#ifdef DIAGNOSTIC
printf("MCLBYTES too small\n");
#endif
/* 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 (n == NULL) {
/* Give up remote */
break;
}
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);
M_COPY_PKTHDR(n, m); /* just for recvif */
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:
printf("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 (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),
IPPROTO_DONE);
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 IPPROTO_DONE;
}
#endif
bzero(&icmp6src, sizeof(icmp6src));
icmp6src.sin6_len = sizeof(struct sockaddr_in6);
icmp6src.sin6_family = AF_INET6;
icmp6src.sin6_addr = ((struct ip6_hdr *)(icmp6 + 1))->ip6_dst;
/* Detect the upper level protocol */
{
void (*ctlfunc) __P((int, struct sockaddr *, void *));
struct ip6_hdr *eip6 = (struct ip6_hdr *)(icmp6 + 1);
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 inf. 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),
IPPROTO_DONE);
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 IPPROTO_DONE;
}
#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),
IPPROTO_DONE);
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 IPPROTO_DONE;
}
#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,
IPPROTO_DONE);
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 IPPROTO_DONE;
}
#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),
IPPROTO_DONE);
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 IPPROTO_DONE;
}
#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 IPPROTO_DONE;
}
#endif
if (icmp6type == ICMP6_PACKET_TOO_BIG) {
if (finaldst == NULL)
finaldst = &((struct ip6_hdr *)(icmp6 + 1))->ip6_dst;
icmp6_mtudisc_update(finaldst, icmp6, m);
}
ctlfunc = (void (*) __P((int, struct sockaddr *, void *)))
(inet6sw[ip6_protox[nxt]].pr_ctlinput);
if (ctlfunc) {
ip6cp.ip6c_m = m;
ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
ip6cp.ip6c_off = eoff;
(*ctlfunc)(code, (struct sockaddr *)&icmp6src, &ip6cp);
}
}
break;
badcode:
icmp6stat.icp6s_badcode++;
break;
badlen:
icmp6stat.icp6s_badlen++;
break;
}
#ifdef HAVE_NRL_INPCB
rip6_input(&m, offp, IPPROTO_ICMPV6);
#else
icmp6_rip6_input(&m, *offp);
#endif
return IPPROTO_DONE;
freeit:
m_freem(m);
return IPPROTO_DONE;
}
static void
icmp6_mtudisc_update(dst, icmp6, m)
struct in6_addr *dst;
struct icmp6_hdr *icmp6;/* we can assume the validity of the pointer */
struct mbuf *m; /* currently unused but added for scoped addrs */
{
u_int mtu = ntohl(icmp6->icmp6_mtu);
struct rtentry *rt = NULL;
struct sockaddr_in6 sin6;
bzero(&sin6, sizeof(sin6));
sin6.sin6_family = PF_INET6;
sin6.sin6_len = sizeof(struct sockaddr_in6);
sin6.sin6_addr = *dst;
/* 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) {
rt->rt_rmx.rmx_mtu = mtu;
}
}
if (rt)
RTFREE(rt);
}
/*
* Process a Node Information Query packet, (roughly) based on
* draft-ietf-ipngwg-icmp-name-lookups-05.
*
* Spec incompatibilities:
* - IPv6 Subject address handling
* - IPv4 Subject address handling support missing
* - Proxy reply (answer even if it's not for me)
* - "Supported Qtypes" support missing
* - joins NI group address at in6_ifattach() time only, does not cope
* with hostname changes by sethostname(3)
*/
#define hostnamelen strlen(hostname)
#ifndef offsetof /* XXX */
#define offsetof(type, member) ((size_t)(&((type *)0)->member))
#endif
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;
struct ip6_hdr *ip6;
int oldfqdn = 0; /* if 1, return pascal string (03 draft) */
char *subj;
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.
*
* We accept packets with the following IPv6 destination address:
* - Responder's unicast/anycast address,
* - link-local multicast address
* This is a violation to last paragraph in icmp-name-lookups-05
* page 4, which restricts IPv6 destination address of a query to:
* - Responder's unicast/anycast address,
* - NI group address for a name belongs to the Responder, or
* - NI group address for a name for which the Responder is providing
* proxy service.
* (note: NI group address is a link-local multicast address)
*
* We allow any link-local multicast address, since "ping6 -w ff02::1"
* has been really useful for us debugging our network. Also this is
* still questionable if the restriction in spec buy us security at all,
* since RFC2463 permits echo packet to multicast destination.
* Even if we forbid NI query to ff02::1, we can effectively get the
* same result as "ping6 -w ff02::1" by the following steps:
* - run "ping6 ff02::1", then
* - run "ping6 -w" for all addresses replied.
*/
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 (ifa_ifwithaddr((struct sockaddr *)&sin6))
; /*unicast/anycast, fine*/
else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr))
; /*violates spec slightly, see above*/
else
goto bad;
/* guess reply length */
qtype = ntohs(ni6->ni_qtype);
switch (qtype) {
case NI_QTYPE_NOOP:
break; /* no reply data */
case NI_QTYPE_SUPTYPES:
goto bad; /* xxx: to be implemented */
break;
case NI_QTYPE_FQDN:
/* XXX will append a mbuf */
replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
break;
case NI_QTYPE_NODEADDR:
addrs = ni6_addrs(ni6, m, &ifp);
if ((replylen += addrs * sizeof(struct in6_addr)) > MCLBYTES)
replylen = MCLBYTES; /* XXX: we'll truncate 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 a mbuf */
replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
oldfqdn++;
break;
}
/* validate query Subject field. */
subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
switch (qtype) {
case NI_QTYPE_NOOP:
case NI_QTYPE_SUPTYPES:
if (subjlen != 0)
goto bad;
break;
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 (subjlen == 0) {
oldfqdn++;
break;
}
if (subjlen != sizeof(sin6.sin6_addr))
goto bad;
/*
* Validate Subject address.
*
* Not sure what exactly does "address belongs to the
* node" mean 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);
/* XXX kame scope hack */
if (IN6_IS_SCOPE_LINKLOCAL(&sin6.sin6_addr)) {
#ifdef FAKE_LOOPBACK_IF
if ((m->m_flags & M_PKTHDR) != 0 &&
m->m_pkthdr.rcvif) {
sin6.sin6_addr.s6_addr16[1] =
htons(m->m_pkthdr.rcvif->if_index);
}
#else
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
sin6.sin6_addr.s6_addr16[1] =
ip6->ip6_dst.s6_addr16[1];
}
#endif
}
if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &sin6.sin6_addr))
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;
default:
/* should never be here due to "switch (qtype)" above */
goto bad;
}
/* allocate a mbuf to reply. */
MGETHDR(n, M_DONTWAIT, m->m_type);
if (n == NULL) {
m_freem(m);
return(NULL);
}
M_COPY_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_flags = 0;
break;
case NI_QTYPE_SUPTYPES:
goto bad; /* xxx: to be implemented */
break;
case NI_QTYPE_FQDN:
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;
if (n->m_flags & M_EXT)
lenlim = MCLBYTES - sizeof(struct ip6_hdr) -
sizeof(struct icmp6_nodeinfo);
else
lenlim = MHLEN - sizeof(struct ip6_hdr) -
sizeof(struct icmp6_nodeinfo);
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;
nni6->ni_code = ICMP6_NI_SUCESS;
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 */
if (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.
*/
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)
struct icmp6_nodeinfo *ni6;
struct mbuf *m;
struct ifnet **ifpp;
{
register struct ifnet *ifp;
register struct in6_ifaddr *ifa6;
register struct ifaddr *ifa;
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
int addrs = 0, addrsofif, iffound = 0;
for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list))
{
addrsofif = 0;
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 (!(ni6->ni_flags & NI_NODEADDR_FLAG_ALL) &&
IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
&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-05]
* So we don't support NI_NODEADDR_FLAG_COMPAT in
* this function at this moment.
*/
if (ifa6->ia6_flags & IN6_IFF_ANYCAST)
continue; /* we need only unicast addresses */
if ((ni6->ni_flags & (NI_NODEADDR_FLAG_LINKLOCAL |
NI_NODEADDR_FLAG_SITELOCAL |
NI_NODEADDR_FLAG_GLOBAL)) == 0)
continue;
/* What do we have to do about ::1? */
switch(in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
case IPV6_ADDR_SCOPE_LINKLOCAL:
if (ni6->ni_flags & NI_NODEADDR_FLAG_LINKLOCAL)
addrsofif++;
break;
case IPV6_ADDR_SCOPE_SITELOCAL:
if (ni6->ni_flags & NI_NODEADDR_FLAG_SITELOCAL)
addrsofif++;
break;
case IPV6_ADDR_SCOPE_GLOBAL:
if (ni6->ni_flags & NI_NODEADDR_FLAG_GLOBAL)
addrsofif++;
break;
default:
continue;
}
}
if (iffound) {
*ifpp = ifp;
return(addrsofif);
}
addrs += addrsofif;
}
return(addrs);
}
static int
ni6_store_addrs(ni6, nni6, ifp0, resid)
struct icmp6_nodeinfo *ni6, *nni6;
struct ifnet *ifp0;
int resid;
{
register struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet);
register struct in6_ifaddr *ifa6;
register struct ifaddr *ifa;
int docopy, copied = 0;
u_char *cp = (u_char *)(nni6 + 1);
if (ifp0 == NULL && !(ni6->ni_flags & NI_NODEADDR_FLAG_ALL))
return(0); /* needless to copy */
for (; ifp; ifp = TAILQ_NEXT(ifp, if_list))
{
for (ifa = ifp->if_addrlist.tqh_first; ifa;
ifa = ifa->ifa_list.tqe_next)
{
docopy = 0;
if (ifa->ifa_addr->sa_family != AF_INET6)
continue;
ifa6 = (struct in6_ifaddr *)ifa;
if (ifa6->ia6_flags & IN6_IFF_ANYCAST) {
/* just experimental. not in the spec. */
if (ni6->ni_flags & NI_NODEADDR_FLAG_ANYCAST)
docopy = 1;
else
continue;
}
else { /* unicast address */
if (ni6->ni_flags & NI_NODEADDR_FLAG_ANYCAST)
continue;
else
docopy = 1;
}
/* What do we have to do about ::1? */
switch(in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
case IPV6_ADDR_SCOPE_LINKLOCAL:
if (ni6->ni_flags & NI_NODEADDR_FLAG_LINKLOCAL)
docopy = 1;
break;
case IPV6_ADDR_SCOPE_SITELOCAL:
if (ni6->ni_flags & NI_NODEADDR_FLAG_SITELOCAL)
docopy = 1;
break;
case IPV6_ADDR_SCOPE_GLOBAL:
if (ni6->ni_flags & NI_NODEADDR_FLAG_GLOBAL)
docopy = 1;
break;
default:
continue;
}
if (docopy) {
if (resid < sizeof(struct in6_addr)) {
/*
* We give up much more copy.
* Set the truncate flag and return.
*/
nni6->ni_flags |=
NI_NODEADDR_FLAG_TRUNCATE;
return(copied);
}
bcopy(&ifa6->ia_addr.sin6_addr, cp,
sizeof(struct in6_addr));
/* XXX: KAME link-local hack; remove ifindex */
if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr))
((struct in6_addr *)cp)->s6_addr16[1] = 0;
cp += sizeof(struct in6_addr);
resid -= sizeof(struct in6_addr);
copied += sizeof(struct in6_addr);
}
}
if (ifp0) /* we need search only on the specified IF */
break;
}
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;
register struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
register struct in6pcb *in6p;
struct in6pcb *last = NULL;
struct sockaddr_in6 rip6src;
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(&rip6src, sizeof(rip6src));
rip6src.sin6_len = sizeof(struct sockaddr_in6);
rip6src.sin6_family = AF_INET6;
/* KAME hack: recover scopeid */
(void)in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif);
LIST_FOREACH(in6p, &ripcb, inp_list)
{
if ((in6p->inp_vflag & INP_IPV6) == NULL)
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 *)&rip6src,
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 *)&rip6src, 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;
#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)) {
printf("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 hack for link-local addresses */
if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst))
ip6->ip6_dst.s6_addr16[1] =
htons(m->m_pkthdr.rcvif->if_index);
if (IN6_IS_ADDR_LINKLOCAL(&t))
t.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index);
#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 would 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 ourseleves.
*/
src = &t;
}
if (src == 0)
/*
* This case matches to multicasts, our anycast, or unicasts
* that we do not own. Select a source address which has the
* same scope.
* XXX: for (non link-local) multicast addresses, this might
* not be a good choice.
*/
if ((ia = in6_ifawithscope(m->m_pkthdr.rcvif, &t)) != 0)
src = &IA6_SIN6(ia)->sin6_addr;
if (src == 0)
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 (m->m_pkthdr.rcvif) {
/* XXX: This may not be the outgoing interface */
ip6->ip6_hlim = nd_ifinfo[m->m_pkthdr.rcvif->if_index].chlim;
}
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 IPSEC
/* Don't lookup socket */
ipsec_setsocket(m, NULL);
#endif /*IPSEC*/
#ifdef COMPAT_RFC1885
ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif);
#else
ip6_output(m, NULL, NULL, 0, NULL, &outif);
#endif
if (outif)
icmp6_ifoutstat_inc(outif, type, code);
return;
bad:
m_freem(m);
return;
}
void
icmp6_fasttimo()
{
mld6_fasttimeo();
/* reset ICMPv6 pps limit */
icmp6errpps_count = 0;
}
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)
register 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)) {
log(LOG_ERR,
"ICMP6 redirect sent from %s rejected; "
"must be from linklocal\n", ip6_sprintf(&src6));
goto freeit;
}
if (ip6->ip6_hlim != 255) {
log(LOG_ERR,
"ICMP6 redirect sent from %s rejected; "
"hlim=%d (must be 255)\n",
ip6_sprintf(&src6), ip6->ip6_hlim);
goto freeit;
}
{
/* 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) {
gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
log(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(rt);
goto freeit;
}
} else {
log(LOG_ERR,
"ICMP6 redirect rejected; "
"no route found for redirect dst: %s\n",
icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
goto freeit;
}
RTFREE(rt);
rt = NULL;
}
if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
log(LOG_ERR,
"ICMP6 redirect rejected; "
"redirect dst must be unicast: %s\n",
icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
goto freeit;
}
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) {
log(LOG_ERR,
"ICMP6 redirect rejected; "
"neither router case nor onlink case: %s\n",
icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
goto freeit;
}
/* validation passed */
icmp6len -= sizeof(*nd_rd);
nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
if (nd6_options(&ndopts) < 0) {
log(LOG_INFO, "icmp6_redirect_input: "
"invalid ND option, rejected: %s\n",
icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
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) {
log(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));
}
/* 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,
(struct rtentry **)NULL);
}
/* 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);
}
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 */
src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src);
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;
maxlen = (m->m_flags & M_EXT) ? MCLBYTES : MHLEN;
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\n", __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->m_next = m0;
m->m_pkthdr.len = m->m_len + m0->m_len;
}
noredhdropt:;
if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src))
sip6->ip6_src.s6_addr16[1] = 0;
if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst))
sip6->ip6_dst.s6_addr16[1] = 0;
#if 0
if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src))
ip6->ip6_src.s6_addr16[1] = 0;
if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst))
ip6->ip6_dst.s6_addr16[1] = 0;
#endif
if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target))
nd_rd->nd_rd_target.s6_addr16[1] = 0;
if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst))
nd_rd->nd_rd_dst.s6_addr16[1] = 0;
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... */
#ifdef IPSEC
/* Don't lookup socket */
ipsec_setsocket(m, NULL);
#endif /*IPSEC*/
ip6_output(m, NULL, NULL, 0, NULL, &outif);
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.
*
* NOTE: for OSes that use NRL inpcb (bsdi4/openbsd), do not forget to modify
* sys/netinet6/raw_ipv6.c:rip6_ctloutput().
*/
int
icmp6_ctloutput(so, sopt)
struct socket *so;
struct sockopt *sopt;
{
int error = 0;
int optlen;
register 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);
}
#ifndef HAVE_RATECHECK
/*
* ratecheck() returns true if it is okay to send. We return
* true if it is not okay to send.
*/
static int
ratecheck(last, limit)
struct timeval *last;
struct timeval *limit;
{
struct timeval tp;
struct timeval nextsend;
microtime(&tp);
tp.tv_sec = time_second;
/* rate limit */
if (last->tv_sec != 0 || last->tv_usec != 0) {
nextsend.tv_sec = last->tv_sec + limit->tv_sec;
nextsend.tv_usec = last->tv_usec + limit->tv_usec;
nextsend.tv_sec += (nextsend.tv_usec / 1000000);
nextsend.tv_usec %= 1000000;
if (nextsend.tv_sec == tp.tv_sec && nextsend.tv_usec <= tp.tv_usec)
;
else if (nextsend.tv_sec <= tp.tv_sec)
;
else {
/* The packet is subject to rate limit */
return 0;
}
}
*last = tp;
return 1;
}
#endif
/*
* 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.
*
* There are two limitations defined:
* - pps limit: ICMPv6 error packet cannot exceed defined packet-per-second.
* we measure it every 0.2 second, since fasttimo works every 0.2 second.
* - rate limit: ICMPv6 error packet cannot appear more than once per
* defined interval.
* In any case, if we perform rate limitation, we'll see jitter in the ICMPv6
* error packets.
*
* 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 */
icmp6errpps_count++;
if (icmp6errppslim && icmp6errpps_count > icmp6errppslim / 5) {
/* The packet is subject to pps limit */
ret++;
}
if (!ratecheck(&icmp6errratelim_last, &icmp6errratelim)) {
/* The packet is subject to rate limit */
ret++;
}
return ret;
}
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