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20d2eee84a
freebsd-skq/sys/netinet6/icmp6.c
shin 50ba589c66 IPSEC support in the kernel. 
pr_input() routines prototype is also changed to support IPSEC and IPV6
chained protocol headers.

Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project
1999-12-22 19:13:38 +00:00

1854 lines
48 KiB
C
Raw Blame History

/*
* 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.
*
* $FreeBSD$
*/
/*
* 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_ipsec.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <sys/domain.h>
#include <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 <netinet6/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/icmp6.h>
#include <netinet6/mld6_var.h>
#include <netinet/in_pcb.h>
#include <netinet6/nd6.h>
#include <netinet6/in6_ifattach.h>
#include <netinet6/ip6protosw.h>
#ifdef IPSEC
#include <netinet6/ipsec.h>
#include <netinet6/ah.h>
#include <netinet6/ipsec6.h>
#include <netinet6/ah6.h>
#include <netkey/key.h>
#ifdef IPSEC_DEBUG
#include <netkey/key_debug.h>
#else
#define KEYDEBUG(lev,arg)
#endif
#endif /* IPSEC */
#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 u_int icmp6errratelim;
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 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
static struct timeval icmp6_nextsend = {0, 0};
void
icmp6_init()
{
mld6_init();
}
/*
* 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 prep;
int off;
u_char nxt;
icmp6stat.icp6s_error++;
if (m->m_flags & M_DECRYPTED)
goto freeit;
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 the erroneous packet is also an ICMP error, discard it.
*/
IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
off = sizeof(struct ip6_hdr);
nxt = oip6->ip6_nxt;
while(1) { /* XXX: should avoid inf. loop explicitly? */
struct ip6_ext *ip6e;
struct icmp6_hdr *icp;
switch(nxt) {
case IPPROTO_IPV6:
case IPPROTO_IPV4:
case IPPROTO_UDP:
case IPPROTO_TCP:
case IPPROTO_ESP:
case IPPROTO_FRAGMENT:
/*
* ICMPv6 error must not be fragmented.
* XXX: but can we trust the sender?
*/
default:
/* What if unknown header followed by ICMP error? */
goto generate;
case IPPROTO_ICMPV6:
IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
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 */
goto generate;
}
case IPPROTO_HOPOPTS:
case IPPROTO_DSTOPTS:
case IPPROTO_ROUTING:
case IPPROTO_AH:
IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct ip6_ext), );
ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off);
if (nxt == IPPROTO_AH)
off += (ip6e->ip6e_len + 2) << 2;
else
off += (ip6e->ip6e_len + 1) << 3;
nxt = ip6e->ip6e_nxt;
break;
}
}
freeit:
/*
* If we can't tell wheter or not we can generate ICMP6, free it.
*/
m_freem(m);
return;
generate:
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);
prep = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
M_PREPEND(m, prep, M_DONTWAIT);
if (m && m->m_len < prep)
m = m_pullup(m, prep);
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*/
}
/*
* 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;
IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
/* m might change if M_LOOP. So, call mtod after this */
/*
* 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
*/
icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
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);
case ICMP6_DST_UNREACH_ADDR:
code = PRC_UNREACH_HOST;
break;
case ICMP6_DST_UNREACH_NOTNEIGHBOR:
code = PRC_UNREACH_SRCFAIL;
break;
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;
{
u_int mtu = ntohl(icmp6->icmp6_mtu);
struct rtentry *rt = NULL;
struct sockaddr_in6 sin6;
code = PRC_MSGSIZE;
bzero(&sin6, sizeof(sin6));
sin6.sin6_family = PF_INET6;
sin6.sin6_len = sizeof(struct sockaddr_in6);
sin6.sin6_addr = ((struct ip6_hdr *)(icmp6 + 1))->ip6_dst;
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);
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) {
int gap, move;
struct mbuf *n0 = n;
/*
* Prepare an internal mbuf. m_pullup() doesn't
* always copy the length we specified.
*/
MGETHDR(n, M_DONTWAIT, n0->m_type);
if (n == NULL) {
/* Give up remote */
m_freem(n0);
break;
}
M_COPY_PKTHDR(n, n0);
n0->m_flags &= ~M_PKTHDR;
n->m_next = 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));
/*
* Adjust mbuf. ip6_plen will be adjusted.
*/
noff = sizeof(struct ip6_hdr);
n->m_len = noff + sizeof(struct icmp6_hdr);
move = off + sizeof(struct icmp6_hdr);
n0->m_len -= move;
n0->m_data += move;
gap = off - noff;
n->m_pkthdr.len -= gap;
} 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);
IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
mld6_input(m, 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 the userland daemon */
case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */
{
enum { WRU, FQDN } mode;
if (code != 0)
goto badcode;
if (icmp6len == sizeof(struct icmp6_hdr) + 4)
mode = WRU;
else if (icmp6len >= sizeof(struct icmp6_hdr) + 8) /* XXX */
mode = FQDN;
else
goto badlen;
#define hostnamelen strlen(hostname)
if (mode == FQDN) {
IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
IPPROTO_DONE);
n = ni6_input(m, off);
noff = sizeof(struct ip6_hdr);
} else {
u_char *p;
MGETHDR(n, M_DONTWAIT, m->m_type);
if (n == NULL) {
/* Give up remote */
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));
p = (u_char *)(nicmp6 + 1);
bzero(p, 4);
bcopy(hostname, p + 4, hostnamelen);
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 + hostnamelen;
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;
IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
nd6_rs_input(m, 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;
IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
nd6_ra_input(m, 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;
IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
nd6_ns_input(m, 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;
IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
nd6_na_input(m, 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;
icmp6_redirect_input(m, 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;
}
IP6_EXTHDR_CHECK(m, off,
sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr),
IPPROTO_DONE);
icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
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;
while (1) { /* XXX: should avoid inf. loop explicitly? */
struct ip6_ext *eh;
switch(nxt) {
case IPPROTO_ESP:
case IPPROTO_NONE:
goto passit;
case IPPROTO_HOPOPTS:
case IPPROTO_DSTOPTS:
case IPPROTO_ROUTING:
case IPPROTO_AH:
case IPPROTO_FRAGMENT:
IP6_EXTHDR_CHECK(m, 0, eoff +
sizeof(struct ip6_ext),
IPPROTO_DONE);
eh = (struct ip6_ext *)(mtod(m, caddr_t)
+ eoff);
if (nxt == IPPROTO_AH)
eoff += (eh->ip6e_len + 2) << 2;
else if (nxt == IPPROTO_FRAGMENT)
eoff += sizeof(struct ip6_frag);
else
eoff += (eh->ip6e_len + 1) << 3;
nxt = eh->ip6e_nxt;
break;
default:
goto notify;
}
}
notify:
icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
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;
}
passit:
icmp6_rip6_input(&m, *offp);
return IPPROTO_DONE;
freeit:
m_freem(m);
return IPPROTO_DONE;
}
/*
* Process a Node Information Query
*/
#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 =
(struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off), *nni6;
struct mbuf *n = NULL;
u_int16_t qtype = ntohs(ni6->ni_qtype);
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 */
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:
replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_name) +
hostnamelen;
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;
replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_name) +
hostnamelen;
break;
}
/* allocate a mbuf to reply. */
MGETHDR(n, M_DONTWAIT, m->m_type);
if (n == NULL)
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(mtod(m, caddr_t) + off, (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:
if (hostnamelen > 255) { /* XXX: rare case, but may happen */
printf("ni6_input: "
"hostname length(%d) is too large for reply\n",
hostnamelen);
goto bad;
}
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. */
fqdn->ni_fqdn_namelen = hostnamelen;
bcopy(hostname, &fqdn->ni_fqdn_name[0], hostnamelen);
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;
return(n);
bad:
if (n)
m_freem(n);
return(NULL);
}
#undef hostnamelen
/*
* 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;
TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
{
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;
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))
{
TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
{
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;
/* this is assumed to be safe. */
icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
bzero(&rip6src, sizeof(rip6src));
rip6src.sin6_len = sizeof(struct sockaddr_in6);
rip6src.sin6_family = AF_INET6;
rip6src.sin6_addr = ip6->ip6_src;
if (IN6_IS_SCOPE_LINKLOCAL(&rip6src.sin6_addr))
rip6src.sin6_addr.s6_addr16[1] = 0;
if (m->m_pkthdr.rcvif) {
if (IN6_IS_SCOPE_LINKLOCAL(&rip6src.sin6_addr))
rip6src.sin6_scope_id = m->m_pkthdr.rcvif->if_index;
else
rip6src.sin6_scope_id = 0;
} else
rip6src.sin6_scope_id = 0;
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 *)&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.
* The caller MUST check if the destination is multicast or not.
* This function is usually called with a unicast destination which
* can be safely the source of the reply packet. But some exceptions
* exist(e.g. ECHOREPLY, PATCKET_TOOBIG, "10" in OPTION type).
* ``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 = mtod(m, struct ip6_hdr *);
struct icmp6_hdr *icmp6;
struct in6_ifaddr *ia;
struct in6_addr t, *src = 0;
int plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
int type, code;
struct ifnet *outif = NULL;
#ifdef COMPAT_RFC1885
int mtu = IPV6_MMTU;
struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst;
#endif
/*
* If there are extra headers between IPv6 and ICMPv6, strip
* off that header first.
*/
if (off != sizeof(struct ip6_hdr)) {
size_t siz;
/* sanity checks */
if (off < sizeof(struct ip6_hdr)) {
printf("sanity fail: off=%x, sizeof(ip6)=%x in %s:%d\n",
(unsigned int)off,
(unsigned int)sizeof(struct ip6_hdr),
__FILE__, __LINE__);
goto bad;
}
siz = off - sizeof(struct ip6_hdr);
if (plen < siz) {
printf("sanity fail: siz=%x, payloadlen=%x in %s:%d\n",
(unsigned int)siz, plen, __FILE__, __LINE__);
goto bad;
}
IP6_EXTHDR_CHECK(m, 0, off, /*nothing*/);
IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), /*nothing*/);
ovbcopy((caddr_t)ip6,
(caddr_t)(mtod(m, u_char *) + siz),
sizeof(struct ip6_hdr));
m->m_data += siz;
m->m_len -= siz;
m->m_pkthdr.len -= siz;
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_nxt = IPPROTO_ICMPV6;
plen -= siz;
}
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.
*/
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) == 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)
/*
* We have not multicast routing yet. So this case matches
* to our multicast, our anycast or not to our unicast.
* Select a source address which has the same scope.
*/
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;
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 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();
}
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 = (struct nd_redirect *)((caddr_t)ip6 + off);
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 = nd_rd->nd_rd_target;
struct in6_addr reddst6 = nd_rd->nd_rd_dst;
union nd_opts ndopts;
if (!m || !ifp)
return;
/* XXX if we are router, we don't update route by icmp6 redirect */
if (ip6_forwarding)
return;
if (!icmp6_rediraccept)
return;
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));
return;
}
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);
return;
}
{
/* 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);
return;
}
} else {
log(LOG_ERR,
"ICMP6 redirect rejected; "
"no route found for redirect dst: %s\n",
icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
return;
}
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));
return;
}
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));
return;
}
/* 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));
return;
}
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
}
}
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;
/* 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 *);
if (nd6_is_addr_neighbor(&sip6->ip6_src, 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)
*/
MGETHDR(m, M_DONTWAIT, MT_HEADER);
if (!m)
goto fail;
if (MHLEN < IPV6_MMTU)
MCLGET(m, M_DONTWAIT);
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))
goto fail;
{
/* get ip6 linklocal address for ifp(my outgoing interface). */
struct in6_ifaddr *ia = in6ifa_ifpforlinklocal(ifp);
if (ia == 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;
/* 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;
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)) {
nd_opt = (struct nd_opt_hdr *)p;
nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
len = 2 + ifp->if_addrlen;
len = (len + 7) & ~7; /*round by 8*/
nd_opt->nd_opt_len = len >> 3;
p += len;
lladdr = (char *)(nd_opt + 1);
bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen);
}
}
nolladdropt:;
m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
/* just to be safe */
if (m0->m_flags & M_DECRYPTED)
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 (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... */
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.
*/
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);
}
/*
* 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 */
{
struct timeval tp;
long sec_diff, usec_diff;
/* If we are not doing rate limitation, it is always okay to send */
if (!icmp6errratelim)
return 0;
microtime(&tp);
tp.tv_sec = time_second;
if (tp.tv_sec < icmp6_nextsend.tv_sec
|| (tp.tv_sec == icmp6_nextsend.tv_sec
&& tp.tv_usec < icmp6_nextsend.tv_usec)) {
/* The packet is subject to rate limit */
return 1;
}
sec_diff = icmp6errratelim / 1000000;
usec_diff = icmp6errratelim % 1000000;
icmp6_nextsend.tv_sec = tp.tv_sec + sec_diff;
if ((tp.tv_usec = tp.tv_usec + usec_diff) >= 1000000) {
icmp6_nextsend.tv_sec++;
icmp6_nextsend.tv_usec -= 1000000;
}
/* it is okay to send this */
return 0;
}
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