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ip6_input.c
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ip6_input.c
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/*
* 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_input.c 8.2 (Berkeley) 1/4/94
*/
#ifdef __FreeBSD__
#include "opt_ip6fw.h"
#endif
#if (defined(__FreeBSD__) && __FreeBSD__ >= 3) || defined(__NetBSD__)
#include "opt_inet.h"
#ifdef __NetBSD__ /*XXX*/
#include "opt_ipsec.h"
#endif
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3)
#include <sys/proc.h>
#endif
#include <net/if.h>
#include <net/if_types.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <net/netisr.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#ifdef INET
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#endif /*INET*/
#if (defined(__FreeBSD__) && __FreeBSD__ >= 3) || defined(__OpenBSD__)
#include <netinet/in_pcb.h>
#endif
#include <netinet6/in6_var.h>
#include <netinet6/ip6.h>
#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3) && !defined(__OpenBSD__)
#include <netinet6/in6_pcb.h>
#endif
#include <netinet6/ip6_var.h>
#include <netinet6/icmp6.h>
#include <netinet6/in6_ifattach.h>
#include <netinet6/nd6.h>
#include <netinet6/in6_prefix.h>
#ifdef IPV6FIREWALL
#include <netinet6/ip6_fw.h>
#endif
#include <netinet6/ip6protosw.h>
/* we need it for NLOOP. */
#ifndef __bsdi__
#include "loop.h"
#endif
#include "faith.h"
#include "gif.h"
#include "bpfilter.h"
#include <net/net_osdep.h>
#ifdef __OpenBSD__ /*KAME IPSEC*/
#undef IPSEC
#endif
extern struct domain inet6domain;
extern struct ip6protosw inet6sw[];
#if defined(__bsdi__) || defined(__OpenBSD__)
extern struct ifnet loif;
#endif
u_char ip6_protox[IPPROTO_MAX];
static int ip6qmaxlen = IFQ_MAXLEN;
struct in6_ifaddr *in6_ifaddr;
struct ifqueue ip6intrq;
#ifdef __NetBSD__
extern struct ifnet loif[NLOOP];
#endif
int ip6_forward_srcrt; /* XXX */
int ip6_sourcecheck; /* XXX */
int ip6_sourcecheck_interval; /* XXX */
#ifdef IPV6FIREWALL
/* firewall hooks */
ip6_fw_chk_t *ip6_fw_chk_ptr;
ip6_fw_ctl_t *ip6_fw_ctl_ptr;
#endif
struct ip6stat ip6stat;
static void ip6_init2 __P((void *));
static int ip6_hopopts_input __P((u_int32_t *, u_int32_t *, struct mbuf **, int *));
#if defined(PTR)
extern int ip6_protocol_tr;
int ptr_in6 __P((struct mbuf *, struct mbuf **));
extern void ip_forward __P((struct mbuf *, int));
#endif
/*
* IP6 initialization: fill in IP6 protocol switch table.
* All protocols not implemented in kernel go to raw IP6 protocol handler.
*/
void
ip6_init()
{
register struct ip6protosw *pr;
register int i;
struct timeval tv;
pr = (struct ip6protosw *)pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
if (pr == 0)
panic("ip6_init");
for (i = 0; i < IPPROTO_MAX; i++)
ip6_protox[i] = pr - inet6sw;
for (pr = (struct ip6protosw *)inet6domain.dom_protosw;
pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW; pr++)
if (pr->pr_domain->dom_family == PF_INET6 &&
pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
ip6_protox[pr->pr_protocol] = pr - inet6sw;
ip6intrq.ifq_maxlen = ip6qmaxlen;
nd6_init();
frag6_init();
#ifdef IPV6FIREWALL
ip6_fw_init();
#endif
/*
* in many cases, random() here does NOT return random number
* as initialization during bootstrap time occur in fixed order.
*/
microtime(&tv);
ip6_flow_seq = random() ^ tv.tv_usec;
#ifndef __FreeBSD__
ip6_init2((void *)0);
#endif
}
static void
ip6_init2(dummy)
void *dummy;
{
#if !(defined(__bsdi__) || defined(__OpenBSD__))
int i;
#endif
int ret;
/* get EUI64 from somewhere */
ret = in6_ifattach_getifid(NULL);
/*
* to route local address of p2p link to loopback,
* assign loopback address first.
*/
#if defined(__bsdi__) || defined(__OpenBSD__)
in6_ifattach(&loif, IN6_IFT_LOOP, NULL, 0);
#else
for (i = 0; i < NLOOP; i++)
in6_ifattach(&loif[i], IN6_IFT_LOOP, NULL, 0);
#endif
/* attach pseudo interfaces */
if (ret == 0)
in6_ifattach_p2p();
/* nd6_timer_init */
timeout(nd6_timer, (caddr_t)0, hz);
/* router renumbering prefix list maintenance */
timeout(in6_rr_timer, (caddr_t)0, hz);
}
#ifdef __FreeBSD__
/* cheat */
SYSINIT(netinet6init2, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip6_init2, NULL);
#endif
/*
* IP6 input interrupt handling. Just pass the packet to ip6_input.
*/
void
ip6intr()
{
int s;
struct mbuf *m;
for (;;) {
s = splimp();
IF_DEQUEUE(&ip6intrq, m);
splx(s);
if (m == 0)
return;
ip6_input(m);
}
}
#ifdef __FreeBSD__
NETISR_SET(NETISR_IPV6, ip6intr);
#endif
extern struct route_in6 ip6_forward_rt;
void
ip6_input(m)
struct mbuf *m;
{
struct ip6_hdr *ip6;
int off = sizeof(struct ip6_hdr), nest;
u_int32_t plen;
u_int32_t rtalert = ~0;
int nxt, ours = 0;
struct ifnet *deliverifp = NULL;
#ifdef IPSEC
/*
* should the inner packet be considered authentic?
* see comment in ah4_input().
*/
if (m) {
m->m_flags &= ~M_AUTHIPHDR;
m->m_flags &= ~M_AUTHIPDGM;
}
#endif
/*
* mbuf statistics by kazu
*/
if (m->m_flags & M_EXT) {
if (m->m_next)
ip6stat.ip6s_mext2m++;
else
ip6stat.ip6s_mext1++;
} else {
if (m->m_next) {
if (m->m_flags & M_LOOP) {
#if defined(__bsdi__) || defined(__OpenBSD__)
ip6stat.ip6s_m2m[loif.if_index]++; /*XXX*/
#else
ip6stat.ip6s_m2m[loif[0].if_index]++; /*XXX*/
#endif
}
else if (m->m_pkthdr.rcvif->if_index <= 31)
ip6stat.ip6s_m2m[m->m_pkthdr.rcvif->if_index]++;
else
ip6stat.ip6s_m2m[0]++;
} else
ip6stat.ip6s_m1++;
}
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_receive);
ip6stat.ip6s_total++;
IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /*nothing*/);
if (m->m_len < sizeof(struct ip6_hdr)) {
struct ifnet *inifp;
inifp = m->m_pkthdr.rcvif;
if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) {
ip6stat.ip6s_toosmall++;
in6_ifstat_inc(inifp, ifs6_in_hdrerr);
return;
}
}
ip6 = mtod(m, struct ip6_hdr *);
if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
ip6stat.ip6s_badvers++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
goto bad;
}
ip6stat.ip6s_nxthist[ip6->ip6_nxt]++;
#ifdef IPV6FIREWALL
/*
* Check with the firewall...
*/
if (ip6_fw_chk_ptr) {
u_short port = 0;
/* If ipfw says divert, we have to just drop packet */
/* use port as a dummy argument */
if ((*ip6_fw_chk_ptr)(&ip6, NULL, &port, &m)) {
m_freem(m);
m = NULL;
}
if (!m)
return;
}
#endif
/*
* Scope check
*/
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) ||
IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) {
ip6stat.ip6s_badscope++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
goto bad;
}
if (IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) ||
IN6_IS_ADDR_LOOPBACK(&ip6->ip6_dst)) {
if (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) {
ours = 1;
deliverifp = m->m_pkthdr.rcvif;
goto hbhcheck;
} else {
ip6stat.ip6s_badscope++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
goto bad;
}
}
if (m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) {
if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) {
ours = 1;
deliverifp = m->m_pkthdr.rcvif;
goto hbhcheck;
}
} else {
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src))
ip6->ip6_src.s6_addr16[1]
= htons(m->m_pkthdr.rcvif->if_index);
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst))
ip6->ip6_dst.s6_addr16[1]
= htons(m->m_pkthdr.rcvif->if_index);
}
#if defined(PTR)
/*
*
*/
if (ip6_protocol_tr)
{
struct mbuf *m1 = NULL;
switch (ptr_in6(m, &m1))
{
case IPPROTO_IP: goto mcastcheck;
case IPPROTO_IPV4: ip_forward(m1, 0); break;
case IPPROTO_IPV6: ip6_forward(m1, 0); break;
case IPPROTO_MAX: /* discard this packet */
default:
}
if (m != m1)
m_freem(m);
return;
}
mcastcheck:
#endif
/*
* Multicast check
*/
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
struct in6_multi *in6m = 0;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mcast);
/*
* See if we belong to the destination multicast group on the
* arrival interface.
*/
IN6_LOOKUP_MULTI(ip6->ip6_dst, m->m_pkthdr.rcvif, in6m);
if (in6m)
ours = 1;
else if (!ip6_mrouter) {
ip6stat.ip6s_notmember++;
ip6stat.ip6s_cantforward++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
goto bad;
}
deliverifp = m->m_pkthdr.rcvif;
goto hbhcheck;
}
/*
* Unicast check
*/
if (ip6_forward_rt.ro_rt == 0 ||
!IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
&ip6_forward_rt.ro_dst.sin6_addr)) {
if (ip6_forward_rt.ro_rt) {
RTFREE(ip6_forward_rt.ro_rt);
ip6_forward_rt.ro_rt = 0;
}
bzero(&ip6_forward_rt.ro_dst, sizeof(struct sockaddr_in6));
ip6_forward_rt.ro_dst.sin6_len = sizeof(struct sockaddr_in6);
ip6_forward_rt.ro_dst.sin6_family = AF_INET6;
ip6_forward_rt.ro_dst.sin6_addr = ip6->ip6_dst;
#if defined(__bsdi__) || defined(__NetBSD__)
rtalloc((struct route *)&ip6_forward_rt);
#endif
#ifdef __FreeBSD__
rtalloc_ign((struct route *)&ip6_forward_rt, RTF_PRCLONING);
#endif
}
#define rt6_key(r) ((struct sockaddr_in6 *)((r)->rt_nodes->rn_key))
/*
* Accept the packet if the forwarding interface to the destination
* according to the routing table is the loopback interface,
* unless the associated route has a gateway.
* Note that this approach causes to accept a packet if there is a
* route to the loopback interface for the destination of the packet.
* But we think it's even useful in some situations, e.g. when using
* a special daemon which wants to intercept the packet.
*/
if (ip6_forward_rt.ro_rt &&
(ip6_forward_rt.ro_rt->rt_flags &
(RTF_HOST|RTF_GATEWAY)) == RTF_HOST &&
#if 0
/*
* The check below is redundant since the comparison of
* the destination and the key of the rtentry has
* already done through looking up the routing table.
*/
IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
&rt6_key(ip6_forward_rt.ro_rt)->sin6_addr) &&
#endif
#if defined(__bsdi__) || defined(__OpenBSD__)
ip6_forward_rt.ro_rt->rt_ifp == &loif
#else
ip6_forward_rt.ro_rt->rt_ifp == &loif[0]
#endif
) {
struct in6_ifaddr *ia6 =
(struct in6_ifaddr *)ip6_forward_rt.ro_rt->rt_ifa;
/* packet to tentative address must not be received */
if (ia6->ia6_flags & IN6_IFF_ANYCAST)
m->m_flags |= M_ANYCAST6;
if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) {
/* this interface is ready */
ours = 1;
deliverifp = ia6->ia_ifp; /* correct? */
goto hbhcheck;
} else {
/* this interface is not ready, fall through */
}
}
/*
* FAITH(Firewall Aided Internet Translator)
*/
#if defined(NFAITH) && 0 < NFAITH
if (ip6_keepfaith) {
if (ip6_forward_rt.ro_rt && ip6_forward_rt.ro_rt->rt_ifp
&& ip6_forward_rt.ro_rt->rt_ifp->if_type == IFT_FAITH) {
/* XXX do we need more sanity checks? */
ours = 1;
deliverifp = ip6_forward_rt.ro_rt->rt_ifp; /*faith*/
goto hbhcheck;
}
}
#endif
#ifdef __OpenBSD__
{
/*
* Last resort: check in6_ifaddr for incoming interface.
* The code is here until I update the "goto ours hack" code above
* working right.
*/
struct ifaddr *ifa;
for (ifa = m->m_pkthdr.rcvif->if_addrlist.tqh_first;
ifa;
ifa = ifa->ifa_list.tqe_next) {
if (ifa->ifa_addr == NULL)
continue; /* just for safety */
if (ifa->ifa_addr->sa_family != AF_INET6)
continue;
if (IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ip6->ip6_dst)) {
ours = 1;
deliverifp = ifa->ifa_ifp;
goto hbhcheck;
}
}
}
#endif
/*
* Now there is no reason to process the packet if it's not our own
* and we're not a router.
*/
if (!ip6_forwarding) {
ip6stat.ip6s_cantforward++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
goto bad;
}
hbhcheck:
/*
* Process Hop-by-Hop options header if it's contained.
* m may be modified in ip6_hopopts_input().
* If a JumboPayload option is included, plen will also be modified.
*/
plen = (u_int32_t)ntohs(ip6->ip6_plen);
if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) {
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
return; /* m have already been freed */
}
/* adjust pointer */
ip6 = mtod(m, struct ip6_hdr *);
nxt = ((struct ip6_hbh *)(ip6 + 1))->ip6h_nxt;
/*
* accept the packet if a router alert option is included
* and we act as an IPv6 router.
*/
if (rtalert != ~0 && ip6_forwarding)
ours = 1;
} else
nxt = ip6->ip6_nxt;
/*
* Check that the amount of data in the buffers
* is as at least much as the IPv6 header would have us expect.
* Trim mbufs if longer than we expect.
* Drop packet if shorter than we expect.
*/
if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) {
ip6stat.ip6s_tooshort++;
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
goto bad;
}
if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) {
if (m->m_len == m->m_pkthdr.len) {
m->m_len = sizeof(struct ip6_hdr) + plen;
m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen;
} else
m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len);
}
/*
* Forward if desirable.
*/
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
/*
* If we are acting as a multicast router, all
* incoming multicast packets are passed to the
* kernel-level multicast forwarding function.
* The packet is returned (relatively) intact; if
* ip6_mforward() returns a non-zero value, the packet
* must be discarded, else it may be accepted below.
*/
if (ip6_mrouter && ip6_mforward(ip6, m->m_pkthdr.rcvif, m)) {
ip6stat.ip6s_cantforward++;
m_freem(m);
return;
}
if (!ours) {
m_freem(m);
return;
}
}
else if (!ours) {
ip6_forward(m, 0);
return;
}
/*
* Tell launch routine the next header
*/
ip6stat.ip6s_delivered++;
in6_ifstat_inc(deliverifp, ifs6_in_deliver);
nest = 0;
while (nxt != IPPROTO_DONE) {
if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) {
ip6stat.ip6s_toomanyhdr++;
goto bad;
}
nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt);
}
return;
bad:
m_freem(m);
}
/*
* Hop-by-Hop options header processing. If a valid jumbo payload option is
* included, the real payload length will be stored in plenp.
*/
static int
ip6_hopopts_input(plenp, rtalertp, mp, offp)
u_int32_t *plenp;
u_int32_t *rtalertp; /* XXX: should be stored more smart way */
struct mbuf **mp;
int *offp;
{
register struct mbuf *m = *mp;
int off = *offp, hbhlen;
struct ip6_hbh *hbh;
u_int8_t *opt;
/* validation of the length of the header */
IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1);
hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
hbhlen = (hbh->ip6h_len + 1) << 3;
IP6_EXTHDR_CHECK(m, off, hbhlen, -1);
hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
off += hbhlen;
hbhlen -= sizeof(struct ip6_hbh);
opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh);
if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh),
hbhlen, rtalertp, plenp) < 0)
return(-1);
*offp = off;
*mp = m;
return(0);
}
/*
* Search header for all Hop-by-hop options and process each option.
* This function is separate from ip6_hopopts_input() in order to
* handle a case where the sending node itself process its hop-by-hop
* options header. In such a case, the function is called from ip6_output().
*/
int
ip6_process_hopopts(m, opthead, hbhlen, rtalertp, plenp)
struct mbuf *m;
u_int8_t *opthead;
int hbhlen;
u_int32_t *rtalertp;
u_int32_t *plenp;
{
struct ip6_hdr *ip6;
int optlen = 0;
u_int8_t *opt = opthead;
u_int16_t rtalert_val;
for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) {
switch(*opt) {
case IP6OPT_PAD1:
optlen = 1;
break;
case IP6OPT_PADN:
if (hbhlen < IP6OPT_MINLEN) {
ip6stat.ip6s_toosmall++;
goto bad;
}
optlen = *(opt + 1) + 2;
break;
case IP6OPT_RTALERT:
/* XXX may need check for alignment */
if (hbhlen < IP6OPT_RTALERT_LEN) {
ip6stat.ip6s_toosmall++;
goto bad;
}
if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2)
/* XXX: should we discard the packet? */
log(LOG_ERR, "length of router alert opt is inconsitent(%d)",
*(opt + 1));
optlen = IP6OPT_RTALERT_LEN;
bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2);
*rtalertp = ntohs(rtalert_val);
break;
case IP6OPT_JUMBO:
/* XXX may need check for alignment */
if (hbhlen < IP6OPT_JUMBO_LEN) {
ip6stat.ip6s_toosmall++;
goto bad;
}
if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2)
/* XXX: should we discard the packet? */
log(LOG_ERR, "length of jumbopayload opt "
"is inconsistent(%d)",
*(opt + 1));
optlen = IP6OPT_JUMBO_LEN;
/*
* We can simply cast because of the alignment
* requirement of the jumbo payload option.
*/
#if 0
*plenp = ntohl(*(u_int32_t *)(opt + 2));
#else
bcopy(opt + 2, plenp, sizeof(*plenp));
*plenp = htonl(*plenp);
#endif
if (*plenp <= IPV6_MAXPACKET) {
/*
* jumbo payload length must be larger
* than 65535
*/
ip6stat.ip6s_badoptions++;
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
sizeof(struct ip6_hdr) +
sizeof(struct ip6_hbh) +
opt + 2 - opthead);
return(-1);
}
ip6 = mtod(m, struct ip6_hdr *);
if (ip6->ip6_plen) {
/*
* IPv6 packets that have non 0 payload length
* must not contain a jumbo paylod option.
*/
ip6stat.ip6s_badoptions++;
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
sizeof(struct ip6_hdr) +
sizeof(struct ip6_hbh) +
opt - opthead);
return(-1);
}
break;
default: /* unknown option */
if (hbhlen < IP6OPT_MINLEN) {
ip6stat.ip6s_toosmall++;
goto bad;
}
if ((optlen = ip6_unknown_opt(opt, m,
sizeof(struct ip6_hdr) +
sizeof(struct ip6_hbh) +
opt - opthead)) == -1)
return(-1);
optlen += 2;
break;
}
}
return(0);
bad:
m_freem(m);
return(-1);
}
/*
* Unknown option processing.
* The third argument `off' is the offset from the IPv6 header to the option,
* which is necessary if the IPv6 header the and option header and IPv6 header
* is not continuous in order to return an ICMPv6 error.
*/
int
ip6_unknown_opt(optp, m, off)
u_int8_t *optp;
struct mbuf *m;
int off;
{
struct ip6_hdr *ip6;
switch(IP6OPT_TYPE(*optp)) {
case IP6OPT_TYPE_SKIP: /* ignore the option */
return((int)*(optp + 1));
case IP6OPT_TYPE_DISCARD: /* silently discard */
m_freem(m);
return(-1);
case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */
ip6stat.ip6s_badoptions++;
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off);
return(-1);
case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */
ip6stat.ip6s_badoptions++;
ip6 = mtod(m, struct ip6_hdr *);
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
(m->m_flags & (M_BCAST|M_MCAST)))
m_freem(m);
else
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_OPTION, off);
return(-1);
}
m_freem(m); /* XXX: NOTREACHED */
return(-1);
}
/*
* Create the "control" list for this pcb
*/
void
ip6_savecontrol(in6p, mp, ip6, m)
#if (defined(__FreeBSD__) && __FreeBSD__ >= 3) || defined(HAVE_NRL_INPCB)
register struct inpcb *in6p;
#else
register struct in6pcb *in6p;
#endif
register struct mbuf **mp;
register struct ip6_hdr *ip6;
register struct mbuf *m;
{
#ifdef __OpenBSD__
# define in6p_flags inp_flags
#endif
#if defined(__NetBSD__) || (defined(__FreeBSD__) && __FreeBSD__ >= 3)
struct proc *p = curproc; /* XXX */
#endif
#ifdef __bsdi__
# define sbcreatecontrol so_cmsg
#endif
int privileged;
privileged = 0;
#if defined(__NetBSD__) || (defined(__FreeBSD__) && __FreeBSD__ >= 3)
if (p && !suser(p->p_ucred, &p->p_acflag))
privileged++;
#else
#ifdef HAVE_NRL_INPCB
if ((in6p->inp_socket->so_state & SS_PRIV) != 0)
privileged++;
#else
if ((in6p->in6p_socket->so_state & SS_PRIV) != 0)
privileged++;
#endif
#endif
#ifdef SO_TIMESTAMP
if (in6p->in6p_socket->so_options & SO_TIMESTAMP) {
struct timeval tv;
microtime(&tv);
*mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
SCM_TIMESTAMP, SOL_SOCKET);
if (*mp)
mp = &(*mp)->m_next;
}
#endif
if (in6p->in6p_flags & IN6P_RECVDSTADDR) {
*mp = sbcreatecontrol((caddr_t) &ip6->ip6_dst,
sizeof(struct in6_addr), IPV6_RECVDSTADDR,
IPPROTO_IPV6);
if (*mp)
mp = &(*mp)->m_next;
}
#ifdef noyet
/* options were tossed above */
if (in6p->in6p_flags & IN6P_RECVOPTS)
/* broken */
/* ip6_srcroute doesn't do what we want here, need to fix */
if (in6p->in6p_flags & IPV6P_RECVRETOPTS)
/* broken */
#endif
/* RFC 2292 sec. 5 */
if (in6p->in6p_flags & IN6P_PKTINFO) {
struct in6_pktinfo pi6;
bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr));
if (IN6_IS_SCOPE_LINKLOCAL(&pi6.ipi6_addr))
pi6.ipi6_addr.s6_addr16[1] = 0;
pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif)
? m->m_pkthdr.rcvif->if_index
: 0;
*mp = sbcreatecontrol((caddr_t) &pi6,
sizeof(struct in6_pktinfo), IPV6_PKTINFO,
IPPROTO_IPV6);
if (*mp)
mp = &(*mp)->m_next;
}
if (in6p->in6p_flags & IN6P_HOPLIMIT) {
int hlim = ip6->ip6_hlim & 0xff;
*mp = sbcreatecontrol((caddr_t) &hlim,
sizeof(int), IPV6_HOPLIMIT, IPPROTO_IPV6);
if (*mp)
mp = &(*mp)->m_next;
}
/* IN6P_NEXTHOP - for outgoing packet only */
/*
* IPV6_HOPOPTS socket option. We require super-user privilege
* for the option, but it might be too strict, since there might
* be some hop-by-hop options which can be returned to normal user.
* See RFC 2292 section 6.
*/
if ((in6p->in6p_flags & IN6P_HOPOPTS) && privileged) {
/*
* Check if a hop-by-hop options header is contatined in the
* received packet, and if so, store the options as ancillary
* data. Note that a hop-by-hop options header must be
* just after the IPv6 header, which fact is assured through
* the IPv6 input processing.
*/
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
struct ip6_hbh *hbh = (struct ip6_hbh *)(ip6 + 1);
/*
* XXX: We copy whole the header even if a jumbo
* payload option is included, which option is to
* be removed before returning in the RFC 2292.
* But it's too painful operation...
*/
*mp = sbcreatecontrol((caddr_t)hbh,
(hbh->ip6h_len + 1) << 3,
IPV6_HOPOPTS, IPPROTO_IPV6);
if (*mp)
mp = &(*mp)->m_next;
}
}
/* IPV6_DSTOPTS and IPV6_RTHDR socket options */
if (in6p->in6p_flags & (IN6P_DSTOPTS | IN6P_RTHDR)) {
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);;
/*
* Search for destination options headers or routing
* header(s) through the header chain, and stores each
* header as ancillary data.
* Note that the order of the headers remains in
* the chain of ancillary data.
*/
while(1) { /* is explicit loop prevention necessary? */
struct ip6_ext *ip6e =
(struct ip6_ext *)(mtod(m, caddr_t) + off);
switch(nxt) {
case IPPROTO_DSTOPTS:
if (!in6p->in6p_flags & IN6P_DSTOPTS)
break;
/*
* We also require super-user privilege for
* the option.
* See the comments on IN6_HOPOPTS.
*/