/* $NetBSD: ip6_input.c,v 1.227 2022/10/28 05:18:39 ozaki-r Exp $ */
/* $KAME: ip6_input.c,v 1.188 2001/03/29 05:34:31 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. 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
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ip6_input.c,v 1.227 2022/10/28 05:18:39 ozaki-r Exp $");
#ifdef _KERNEL_OPT
#include "opt_gateway.h"
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include "opt_net_mpsafe.h"
#endif
#include <sys/param.h>
#include <sys/systm.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>
#include <sys/proc.h>
#include <sys/sysctl.h>
#include <sys/cprng.h>
#include <sys/percpu.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <net/pktqueue.h>
#include <net/pfil.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#ifdef INET
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/ip_icmp.h>
#endif /* INET */
#include <netinet/ip6.h>
#include <netinet/portalgo.h>
#include <netinet6/in6_var.h>
#include <netinet6/ip6_var.h>
#include <netinet6/ip6_private.h>
#include <netinet6/in6_pcb.h>
#include <netinet/icmp6.h>
#include <netinet6/scope6_var.h>
#include <netinet6/in6_ifattach.h>
#include <netinet6/nd6.h>
#ifdef IPSEC
#include <netipsec/ipsec.h>
#include <netipsec/ipsec6.h>
#include <netipsec/key.h>
#endif /* IPSEC */
#include <netinet6/ip6protosw.h>
#include "faith.h"
extern struct domain inet6domain;
u_char ip6_protox[IPPROTO_MAX];
pktqueue_t *ip6_pktq __read_mostly;
pfil_head_t *inet6_pfil_hook;
percpu_t *ip6stat_percpu;
percpu_t *ip6_forward_rt_percpu __cacheline_aligned;
static void ip6intr(void *);
static void ip6_input(struct mbuf *, struct ifnet *);
static bool ip6_badaddr(struct ip6_hdr *);
static struct m_tag *ip6_setdstifaddr(struct mbuf *, const struct in6_ifaddr *);
static struct m_tag *ip6_addaux(struct mbuf *);
static struct m_tag *ip6_findaux(struct mbuf *);
static void ip6_delaux(struct mbuf *);
static int ip6_process_hopopts(struct mbuf *, u_int8_t *, int, u_int32_t *,
u_int32_t *);
static struct mbuf *ip6_pullexthdr(struct mbuf *, size_t, int);
static void sysctl_net_inet6_ip6_setup(struct sysctllog **);
#ifdef NET_MPSAFE
#define SOFTNET_LOCK() mutex_enter(softnet_lock)
#define SOFTNET_UNLOCK() mutex_exit(softnet_lock)
#else
#define SOFTNET_LOCK() KASSERT(mutex_owned(softnet_lock))
#define SOFTNET_UNLOCK() KASSERT(mutex_owned(softnet_lock))
#endif
/* Ensure that non packed structures are the desired size. */
__CTASSERT(sizeof(struct ip6_hdr) == 40);
__CTASSERT(sizeof(struct ip6_ext) == 2);
__CTASSERT(sizeof(struct ip6_hbh) == 2);
__CTASSERT(sizeof(struct ip6_dest) == 2);
__CTASSERT(sizeof(struct ip6_opt) == 2);
__CTASSERT(sizeof(struct ip6_opt_jumbo) == 6);
__CTASSERT(sizeof(struct ip6_opt_nsap) == 4);
__CTASSERT(sizeof(struct ip6_opt_tunnel) == 3);
__CTASSERT(sizeof(struct ip6_opt_router) == 4);
__CTASSERT(sizeof(struct ip6_rthdr) == 4);
__CTASSERT(sizeof(struct ip6_rthdr0) == 8);
__CTASSERT(sizeof(struct ip6_frag) == 8);
/*
* IP6 initialization: fill in IP6 protocol switch table.
* All protocols not implemented in kernel go to raw IP6 protocol handler.
*/
void
ip6_init(void)
{
const struct ip6protosw *pr;
int i;
in6_init();
ip6_pktq = pktq_create(IFQ_MAXLEN, ip6intr, NULL);
KASSERT(ip6_pktq != NULL);
sysctl_net_inet6_ip6_setup(NULL);
pr = (const 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 = (const struct ip6protosw *)inet6domain.dom_protosw;
pr < (const 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;
scope6_init();
addrsel_policy_init();
nd6_init();
frag6_init();
#ifdef GATEWAY
ip6flow_init(ip6_hashsize);
#endif
/* Register our Packet Filter hook. */
inet6_pfil_hook = pfil_head_create(PFIL_TYPE_AF, (void *)AF_INET6);
KASSERT(inet6_pfil_hook != NULL);
ip6stat_percpu = percpu_alloc(sizeof(uint64_t) * IP6_NSTATS);
ip6_forward_rt_percpu = rtcache_percpu_alloc();
}
/*
* IP6 input interrupt handling. Just pass the packet to ip6_input.
*/
static void
ip6intr(void *arg __unused)
{
struct mbuf *m;
SOFTNET_KERNEL_LOCK_UNLESS_NET_MPSAFE();
while ((m = pktq_dequeue(ip6_pktq)) != NULL) {
struct psref psref;
struct ifnet *rcvif = m_get_rcvif_psref(m, &psref);
if (rcvif == NULL) {
IP6_STATINC(IP6_STAT_IFDROP);
m_freem(m);
continue;
}
/*
* Drop the packet if IPv6 is disabled on the interface.
*/
if ((ND_IFINFO(rcvif)->flags & ND6_IFF_IFDISABLED)) {
m_put_rcvif_psref(rcvif, &psref);
IP6_STATINC(IP6_STAT_IFDROP);
m_freem(m);
continue;
}
ip6_input(m, rcvif);
m_put_rcvif_psref(rcvif, &psref);
}
SOFTNET_KERNEL_UNLOCK_UNLESS_NET_MPSAFE();
}
static void
ip6_input(struct mbuf *m, struct ifnet *rcvif)
{
struct ip6_hdr *ip6;
int hit, off = sizeof(struct ip6_hdr), nest;
u_int32_t plen;
u_int32_t rtalert = ~0;
int nxt, ours = 0, rh_present = 0, frg_present;
struct ifnet *deliverifp = NULL;
int srcrt = 0;
struct rtentry *rt = NULL;
union {
struct sockaddr dst;
struct sockaddr_in6 dst6;
} u;
struct route *ro;
KASSERT(rcvif != NULL);
/*
* make sure we don't have onion peering information into m_tag.
*/
ip6_delaux(m);
/*
* mbuf statistics
*/
if (m->m_flags & M_EXT) {
if (m->m_next)
IP6_STATINC(IP6_STAT_MEXT2M);
else
IP6_STATINC(IP6_STAT_MEXT1);
} else {
#define M2MMAX 32
if (m->m_next) {
if (m->m_flags & M_LOOP)
/*XXX*/ IP6_STATINC(IP6_STAT_M2M + lo0ifp->if_index);
else if (rcvif->if_index < M2MMAX)
IP6_STATINC(IP6_STAT_M2M + rcvif->if_index);
else
IP6_STATINC(IP6_STAT_M2M);
} else
IP6_STATINC(IP6_STAT_M1);
#undef M2MMAX
}
in6_ifstat_inc(rcvif, ifs6_in_receive);
IP6_STATINC(IP6_STAT_TOTAL);
/*
* If the IPv6 header is not aligned, slurp it up into a new
* mbuf with space for link headers, in the event we forward
* it. Otherwise, if it is aligned, make sure the entire base
* IPv6 header is in the first mbuf of the chain.
*/
if (M_GET_ALIGNED_HDR(&m, struct ip6_hdr, true) != 0) {
/* XXXJRT new stat, please */
IP6_STATINC(IP6_STAT_TOOSMALL);
in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
return;
}
ip6 = mtod(m, struct ip6_hdr *);
if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
IP6_STATINC(IP6_STAT_BADVERS);
in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
goto bad;
}
if (ip6_badaddr(ip6)) {
IP6_STATINC(IP6_STAT_BADSCOPE);
in6_ifstat_inc(rcvif, ifs6_in_addrerr);
goto bad;
}
/*
* Assume that we can create a fast-forward IP flow entry
* based on this packet.
*/
m->m_flags |= M_CANFASTFWD;
/*
* Run through list of hooks for input packets. If there are any
* filters which require that additional packets in the flow are
* not fast-forwarded, they must clear the M_CANFASTFWD flag.
* Note that filters must _never_ set this flag, as another filter
* in the list may have previously cleared it.
*
* Don't call hooks if the packet has already been processed by
* IPsec (encapsulated, tunnel mode).
*/
#if defined(IPSEC)
if (!ipsec_used || !ipsec_skip_pfil(m))
#else
if (1)
#endif
{
struct in6_addr odst;
int error;
odst = ip6->ip6_dst;
error = pfil_run_hooks(inet6_pfil_hook, &m, rcvif, PFIL_IN);
if (error != 0 || m == NULL) {
IP6_STATINC(IP6_STAT_PFILDROP_IN);
return;
}
if (m->m_len < sizeof(struct ip6_hdr)) {
if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) {
IP6_STATINC(IP6_STAT_TOOSMALL);
in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
return;
}
}
ip6 = mtod(m, struct ip6_hdr *);
srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst);
}
IP6_STATINC(IP6_STAT_NXTHIST + ip6->ip6_nxt);
#ifdef ALTQ
if (altq_input != NULL) {
SOFTNET_LOCK();
if ((*altq_input)(m, AF_INET6) == 0) {
SOFTNET_UNLOCK();
/* packet is dropped by traffic conditioner */
return;
}
SOFTNET_UNLOCK();
}
#endif
/*
* Disambiguate address scope zones (if there is ambiguity).
* We first make sure that the original source or destination address
* is not in our internal form for scoped addresses. Such addresses
* are not necessarily invalid spec-wise, but we cannot accept them due
* to the usage conflict.
* in6_setscope() then also checks and rejects the cases where src or
* dst are the loopback address and the receiving interface
* is not loopback.
*/
if (__predict_false(
m_makewritable(&m, 0, sizeof(struct ip6_hdr), M_DONTWAIT))) {
IP6_STATINC(IP6_STAT_IDROPPED);
goto bad;
}
ip6 = mtod(m, struct ip6_hdr *);
if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) {
IP6_STATINC(IP6_STAT_BADSCOPE); /* XXX */
goto bad;
}
if (in6_setscope(&ip6->ip6_src, rcvif, NULL) ||
in6_setscope(&ip6->ip6_dst, rcvif, NULL)) {
IP6_STATINC(IP6_STAT_BADSCOPE);
goto bad;
}
ro = rtcache_percpu_getref(ip6_forward_rt_percpu);
/*
* Multicast check
*/
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
bool ingroup;
in6_ifstat_inc(rcvif, ifs6_in_mcast);
/*
* See if we belong to the destination multicast group on the
* arrival interface.
*/
ingroup = in6_multi_group(&ip6->ip6_dst, rcvif);
if (ingroup) {
ours = 1;
} else if (!ip6_mrouter) {
uint64_t *ip6s = IP6_STAT_GETREF();
ip6s[IP6_STAT_NOTMEMBER]++;
ip6s[IP6_STAT_CANTFORWARD]++;
IP6_STAT_PUTREF();
in6_ifstat_inc(rcvif, ifs6_in_discard);
goto bad_unref;
}
deliverifp = rcvif;
goto hbhcheck;
}
sockaddr_in6_init(&u.dst6, &ip6->ip6_dst, 0, 0, 0);
/*
* Unicast check
*/
rt = rtcache_lookup2(ro, &u.dst, 1, &hit);
if (hit)
IP6_STATINC(IP6_STAT_FORWARD_CACHEHIT);
else
IP6_STATINC(IP6_STAT_FORWARD_CACHEMISS);
/*
* 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.
*
* We don't explicitly match ip6_dst against an interface here. It
* is already done in rtcache_lookup2: rt->rt_ifp->if_type will be
* IFT_LOOP if the packet is for us.
*
* 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 (rt != NULL &&
(rt->rt_flags & (RTF_HOST|RTF_GATEWAY)) == RTF_HOST &&
rt->rt_ifp->if_type == IFT_LOOP) {
struct in6_ifaddr *ia6 = (struct in6_ifaddr *)rt->rt_ifa;
int addrok;
if (ia6->ia6_flags & IN6_IFF_ANYCAST)
m->m_flags |= M_ANYCAST6;
/*
* packets to a tentative, duplicated, or somehow invalid
* address must not be accepted.
*/
if (ia6->ia6_flags & IN6_IFF_NOTREADY)
addrok = 0;
else if (ia6->ia6_flags & IN6_IFF_DETACHED &&
!IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src))
{
/* Allow internal traffic to DETACHED addresses */
struct sockaddr_in6 sin6;
int s;
memset(&sin6, 0, sizeof(sin6));
sin6.sin6_family = AF_INET6;
sin6.sin6_len = sizeof(sin6);
sin6.sin6_addr = ip6->ip6_src;
s = pserialize_read_enter();
addrok = (ifa_ifwithaddr(sin6tosa(&sin6)) != NULL);
pserialize_read_exit(s);
} else
addrok = 1;
if (addrok) {
/* this address is ready */
ours = 1;
deliverifp = ia6->ia_ifp; /* correct? */
goto hbhcheck;
} else {
/* address is not ready, so discard the packet. */
char ip6bufs[INET6_ADDRSTRLEN];
char ip6bufd[INET6_ADDRSTRLEN];
nd6log(LOG_INFO, "packet to an unready address %s->%s\n",
IN6_PRINT(ip6bufs, &ip6->ip6_src),
IN6_PRINT(ip6bufd, &ip6->ip6_dst));
IP6_STATINC(IP6_STAT_IDROPPED);
goto bad_unref;
}
}
/*
* FAITH (Firewall Aided Internet Translator)
*/
#if defined(NFAITH) && 0 < NFAITH
if (ip6_keepfaith) {
if (rt != NULL && rt->rt_ifp != NULL &&
rt->rt_ifp->if_type == IFT_FAITH) {
/* XXX do we need more sanity checks? */
ours = 1;
deliverifp = rt->rt_ifp; /* faith */
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) {
IP6_STATINC(IP6_STAT_CANTFORWARD);
in6_ifstat_inc(rcvif, ifs6_in_discard);
goto bad_unref;
}
hbhcheck:
/*
* Record address information into m_tag, if we don't have one yet.
* Note that we are unable to record it, if the address is not listed
* as our interface address (e.g. multicast addresses, addresses
* within FAITH prefixes and such).
*/
if (deliverifp && ip6_getdstifaddr(m) == NULL) {
struct in6_ifaddr *ia6;
int s = pserialize_read_enter();
ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst);
/* Depends on ip6_setdstifaddr never sleep */
if (ia6 != NULL && ip6_setdstifaddr(m, ia6) == NULL) {
/*
* XXX maybe we should drop the packet here,
* as we could not provide enough information
* to the upper layers.
*/
}
pserialize_read_exit(s);
}
/*
* 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) {
struct ip6_hbh *hbh;
if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) {
/* m already freed */
in6_ifstat_inc(rcvif, ifs6_in_discard);
rtcache_unref(rt, ro);
rtcache_percpu_putref(ip6_forward_rt_percpu);
return;
}
/* adjust pointer */
ip6 = mtod(m, struct ip6_hdr *);
/*
* if the payload length field is 0 and the next header field
* indicates Hop-by-Hop Options header, then a Jumbo Payload
* option MUST be included.
*/
if (ip6->ip6_plen == 0 && plen == 0) {
/*
* Note that if a valid jumbo payload option is
* contained, ip6_hopopts_input() must set a valid
* (non-zero) payload length to the variable plen.
*/
IP6_STATINC(IP6_STAT_BADOPTIONS);
in6_ifstat_inc(rcvif, ifs6_in_discard);
in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
(char *)&ip6->ip6_plen - (char *)ip6);
rtcache_unref(rt, ro);
rtcache_percpu_putref(ip6_forward_rt_percpu);
return;
}
IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
sizeof(struct ip6_hbh));
if (hbh == NULL) {
IP6_STATINC(IP6_STAT_TOOSHORT);
rtcache_unref(rt, ro);
rtcache_percpu_putref(ip6_forward_rt_percpu);
return;
}
KASSERT(ACCESSIBLE_POINTER(hbh, struct ip6_hdr));
nxt = hbh->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 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) {
IP6_STATINC(IP6_STAT_TOOSHORT);
in6_ifstat_inc(rcvif, ifs6_in_truncated);
goto bad_unref;
}
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 != NULL) {
int error;
SOFTNET_LOCK();
error = ip6_mforward(ip6, rcvif, m);
SOFTNET_UNLOCK();
if (error != 0) {
rtcache_unref(rt, ro);
rtcache_percpu_putref(ip6_forward_rt_percpu);
IP6_STATINC(IP6_STAT_CANTFORWARD);
goto bad;
}
}
if (!ours) {
IP6_STATINC(IP6_STAT_CANTFORWARD);
goto bad_unref;
}
} else if (!ours) {
rtcache_unref(rt, ro);
rtcache_percpu_putref(ip6_forward_rt_percpu);
ip6_forward(m, srcrt, rcvif);
return;
}
ip6 = mtod(m, struct ip6_hdr *);
/*
* Malicious party may be able to use IPv4 mapped addr to confuse
* tcp/udp stack and bypass security checks (act as if it was from
* 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious.
*
* For SIIT end node behavior, you may want to disable the check.
* However, you will become vulnerable to attacks using IPv4 mapped
* source.
*/
if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
IP6_STATINC(IP6_STAT_BADSCOPE);
in6_ifstat_inc(rcvif, ifs6_in_addrerr);
goto bad_unref;
}
#ifdef IFA_STATS
if (deliverifp != NULL) {
struct in6_ifaddr *ia6;
int s = pserialize_read_enter();
ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst);
if (ia6)
ia6->ia_ifa.ifa_data.ifad_inbytes += m->m_pkthdr.len;
pserialize_read_exit(s);
}
#endif
IP6_STATINC(IP6_STAT_DELIVERED);
in6_ifstat_inc(deliverifp, ifs6_in_deliver);
nest = 0;
if (rt != NULL) {
rtcache_unref(rt, ro);
rt = NULL;
}
rtcache_percpu_putref(ip6_forward_rt_percpu);
rh_present = 0;
frg_present = 0;
while (nxt != IPPROTO_DONE) {
if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) {
IP6_STATINC(IP6_STAT_TOOMANYHDR);
in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
goto bad;
}
M_VERIFY_PACKET(m);
/*
* protection against faulty packet - there should be
* more sanity checks in header chain processing.
*/
if (m->m_pkthdr.len < off) {
IP6_STATINC(IP6_STAT_TOOSHORT);
in6_ifstat_inc(rcvif, ifs6_in_truncated);
goto bad;
}
if (nxt == IPPROTO_ROUTING) {
if (rh_present++) {
in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
IP6_STATINC(IP6_STAT_BADOPTIONS);
goto bad;
}
} else if (nxt == IPPROTO_FRAGMENT) {
if (frg_present++) {
in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
IP6_STATINC(IP6_STAT_BADOPTIONS);
goto bad;
}
}
#ifdef IPSEC
if (ipsec_used) {
/*
* Enforce IPsec policy checking if we are seeing last
* header. Note that we do not visit this with
* protocols with pcb layer code - like udp/tcp/raw ip.
*/
if ((inet6sw[ip6_protox[nxt]].pr_flags
& PR_LASTHDR) != 0) {
int error;
error = ipsec_ip_input_checkpolicy(m, false);
if (error) {
IP6_STATINC(IP6_STAT_IPSECDROP_IN);
goto bad;
}
}
}
#endif
nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt);
}
return;
bad_unref:
rtcache_unref(rt, ro);
rtcache_percpu_putref(ip6_forward_rt_percpu);
bad:
m_freem(m);
return;
}
static bool
ip6_badaddr(struct ip6_hdr *ip6)
{
/* Check against address spoofing/corruption. */
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) ||
IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) {
return true;
}
/*
* The following check is not documented in specs. A malicious
* party may be able to use IPv4 mapped addr to confuse tcp/udp stack
* and bypass security checks (act as if it was from 127.0.0.1 by using
* IPv6 src ::ffff:127.0.0.1). Be cautious.
*
* This check chokes if we are in an SIIT cloud. As none of BSDs
* support IPv4-less kernel compilation, we cannot support SIIT
* environment at all. So, it makes more sense for us to reject any
* malicious packets for non-SIIT environment, than try to do a
* partial support for SIIT environment.
*/
if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
return true;
}
/*
* Reject packets with IPv4-compatible IPv6 addresses (RFC4291).
*/
if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) ||
IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) {
return true;
}
return false;
}
/*
* set/grab in6_ifaddr correspond to IPv6 destination address.
*/
static struct m_tag *
ip6_setdstifaddr(struct mbuf *m, const struct in6_ifaddr *ia)
{
struct m_tag *mtag;
struct ip6aux *ip6a;
mtag = ip6_addaux(m);
if (mtag == NULL)
return NULL;
ip6a = (struct ip6aux *)(mtag + 1);
if (in6_setscope(&ip6a->ip6a_src, ia->ia_ifp, &ip6a->ip6a_scope_id)) {
IP6_STATINC(IP6_STAT_BADSCOPE);
return NULL;
}
ip6a->ip6a_src = ia->ia_addr.sin6_addr;
ip6a->ip6a_flags = ia->ia6_flags;
return mtag;
}
const struct ip6aux *
ip6_getdstifaddr(struct mbuf *m)
{
struct m_tag *mtag;
mtag = ip6_findaux(m);
if (mtag != NULL)
return (struct ip6aux *)(mtag + 1);
else
return NULL;
}
/*
* Hop-by-Hop options header processing. If a valid jumbo payload option is
* included, the real payload length will be stored in plenp.
*
* rtalertp - XXX: should be stored more smart way
*/
int
ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp,
struct mbuf **mp, int *offp)
{
struct mbuf *m = *mp;
int off = *offp, hbhlen;
struct ip6_hbh *hbh;
/* validation of the length of the header */
IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m,
sizeof(struct ip6_hdr), sizeof(struct ip6_hbh));
if (hbh == NULL) {
IP6_STATINC(IP6_STAT_TOOSHORT);
return -1;
}
hbhlen = (hbh->ip6h_len + 1) << 3;
IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
hbhlen);
if (hbh == NULL) {
IP6_STATINC(IP6_STAT_TOOSHORT);
return -1;
}
KASSERT(ACCESSIBLE_POINTER(hbh, struct ip6_hdr));
off += hbhlen;
hbhlen -= 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().
*
* The function assumes that hbh header is located right after the IPv6 header
* (RFC2460 p7), opthead is pointer into data content in m, and opthead to
* opthead + hbhlen is located in continuous memory region.
*/
static int
ip6_process_hopopts(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;
u_int32_t jumboplen;
const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh);
for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) {
switch (*opt) {
case IP6OPT_PAD1:
optlen = 1;
break;
case IP6OPT_PADN:
if (hbhlen < IP6OPT_MINLEN) {
IP6_STATINC(IP6_STAT_TOOSMALL);
goto bad;
}
optlen = *(opt + 1) + 2;
break;
case IP6OPT_RTALERT:
/* XXX may need check for alignment */
if (hbhlen < IP6OPT_RTALERT_LEN) {
IP6_STATINC(IP6_STAT_TOOSMALL);
goto bad;
}
if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) {
IP6_STATINC(IP6_STAT_BADOPTIONS);
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
erroff + opt + 1 - opthead);
return (-1);
}
optlen = IP6OPT_RTALERT_LEN;
memcpy((void *)&rtalert_val, (void *)(opt + 2), 2);
*rtalertp = ntohs(rtalert_val);
break;
case IP6OPT_JUMBO:
/* XXX may need check for alignment */
if (hbhlen < IP6OPT_JUMBO_LEN) {
IP6_STATINC(IP6_STAT_TOOSMALL);
goto bad;
}
if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) {
IP6_STATINC(IP6_STAT_BADOPTIONS);
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
erroff + opt + 1 - opthead);
return (-1);
}
optlen = IP6OPT_JUMBO_LEN;
/*
* IPv6 packets that have non 0 payload length
* must not contain a jumbo payload option.
*/
ip6 = mtod(m, struct ip6_hdr *);
if (ip6->ip6_plen) {
IP6_STATINC(IP6_STAT_BADOPTIONS);
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
erroff + opt - opthead);
return (-1);
}
/*
* We may see jumbolen in unaligned location, so
* we'd need to perform memcpy().
*/
memcpy(&jumboplen, opt + 2, sizeof(jumboplen));
jumboplen = (u_int32_t)htonl(jumboplen);
#if 1
/*
* if there are multiple jumbo payload options,
* *plenp will be non-zero and the packet will be
* rejected.
* the behavior may need some debate in ipngwg -
* multiple options does not make sense, however,
* there's no explicit mention in specification.
*/
if (*plenp != 0) {
IP6_STATINC(IP6_STAT_BADOPTIONS);
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
erroff + opt + 2 - opthead);
return (-1);
}
#endif
/*
* jumbo payload length must be larger than 65535.
*/
if (jumboplen <= IPV6_MAXPACKET) {
IP6_STATINC(IP6_STAT_BADOPTIONS);
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
erroff + opt + 2 - opthead);
return (-1);
}
*plenp = jumboplen;
break;
default: /* unknown option */
if (hbhlen < IP6OPT_MINLEN) {
IP6_STATINC(IP6_STAT_TOOSMALL);
goto bad;
}
optlen = ip6_unknown_opt(opt, m,
erroff + opt - opthead);
if (optlen == -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(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 */
IP6_STATINC(IP6_STAT_BADOPTIONS);
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off);
return (-1);
case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */
IP6_STATINC(IP6_STAT_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);
}
void
ip6_savecontrol(struct inpcb *inp, struct mbuf **mp,
struct ip6_hdr *ip6, struct mbuf *m)
{
struct socket *so = inp->inp_socket;
#ifdef RFC2292
#define IS2292(x, y) ((inp->inp_flags & IN6P_RFC2292) ? (x) : (y))
#else
#define IS2292(x, y) (y)
#endif
KASSERT(m->m_flags & M_PKTHDR);
if (SOOPT_TIMESTAMP(so->so_options))
mp = sbsavetimestamp(so->so_options, mp);
/* some OSes call this logic with IPv4 packet, for SO_TIMESTAMP */
if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION)
return;
/* RFC 2292 sec. 5 */
if ((inp->inp_flags & IN6P_PKTINFO) != 0) {
struct in6_pktinfo pi6;
memcpy(&pi6.ipi6_addr, &ip6->ip6_dst, sizeof(struct in6_addr));
in6_clearscope(&pi6.ipi6_addr); /* XXX */
pi6.ipi6_ifindex = m->m_pkthdr.rcvif_index;
*mp = sbcreatecontrol(&pi6, sizeof(pi6),
IS2292(IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6);
if (*mp)
mp = &(*mp)->m_next;
}
if (inp->inp_flags & IN6P_HOPLIMIT) {
int hlim = ip6->ip6_hlim & 0xff;
*mp = sbcreatecontrol(&hlim, sizeof(hlim),
IS2292(IPV6_2292HOPLIMIT, IPV6_HOPLIMIT), IPPROTO_IPV6);
if (*mp)
mp = &(*mp)->m_next;
}
if ((inp->inp_flags & IN6P_TCLASS) != 0) {
u_int32_t flowinfo;
int tclass;
flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK);
flowinfo >>= 20;
tclass = flowinfo & 0xff;
*mp = sbcreatecontrol(&tclass, sizeof(tclass),
IPV6_TCLASS, IPPROTO_IPV6);
if (*mp)
mp = &(*mp)->m_next;
}
/*
* IPV6_HOPOPTS socket option. Recall that we required super-user
* privilege for the option (see ip6_ctloutput), but it might be too
* strict, since there might be some hop-by-hop options which can be
* returned to normal user.
* See also RFC3542 section 8 (or RFC2292 section 6).
*/
if ((inp->inp_flags & IN6P_HOPOPTS) != 0) {
/*
* 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 *xip6 = mtod(m, struct ip6_hdr *);
if (xip6->ip6_nxt == IPPROTO_HOPOPTS) {
struct ip6_hbh *hbh;
int hbhlen;
struct mbuf *ext;
ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr),
xip6->ip6_nxt);
if (ext == NULL) {
IP6_STATINC(IP6_STAT_TOOSHORT);
return;
}
hbh = mtod(ext, struct ip6_hbh *);
hbhlen = (hbh->ip6h_len + 1) << 3;
if (hbhlen != ext->m_len) {
m_freem(ext);
IP6_STATINC(IP6_STAT_TOOSHORT);
return;
}
/*
* 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.
* Note: this constraint is removed in RFC3542.
*/
*mp = sbcreatecontrol(hbh, hbhlen,
IS2292(IPV6_2292HOPOPTS, IPV6_HOPOPTS),
IPPROTO_IPV6);
if (*mp)
mp = &(*mp)->m_next;
m_freem(ext);
}
}
/* IPV6_DSTOPTS and IPV6_RTHDR socket options */
if (inp->inp_flags & (IN6P_DSTOPTS | IN6P_RTHDR)) {
struct ip6_hdr *xip6 = mtod(m, struct ip6_hdr *);
int nxt = xip6->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.
*/
for (;;) { /* is explicit loop prevention necessary? */
struct ip6_ext *ip6e = NULL;
int elen;
struct mbuf *ext = NULL;
/*
* if it is not an extension header, don't try to
* pull it from the chain.
*/
switch (nxt) {
case IPPROTO_DSTOPTS:
case IPPROTO_ROUTING:
case IPPROTO_HOPOPTS:
case IPPROTO_AH: /* is it possible? */
break;
default:
goto loopend;
}
ext = ip6_pullexthdr(m, off, nxt);
if (ext == NULL) {
IP6_STATINC(IP6_STAT_TOOSHORT);
return;
}
ip6e = mtod(ext, struct ip6_ext *);
if (nxt == IPPROTO_AH)
elen = (ip6e->ip6e_len + 2) << 2;
else
elen = (ip6e->ip6e_len + 1) << 3;
if (elen != ext->m_len) {
m_freem(ext);
IP6_STATINC(IP6_STAT_TOOSHORT);
return;
}
KASSERT(ACCESSIBLE_POINTER(ip6e, struct ip6_hdr));
switch (nxt) {
case IPPROTO_DSTOPTS:
if (!(inp->inp_flags & IN6P_DSTOPTS))
break;
*mp = sbcreatecontrol(ip6e, elen,
IS2292(IPV6_2292DSTOPTS, IPV6_DSTOPTS),
IPPROTO_IPV6);
if (*mp)
mp = &(*mp)->m_next;
break;
case IPPROTO_ROUTING:
if (!(inp->inp_flags & IN6P_RTHDR))
break;
*mp = sbcreatecontrol(ip6e, elen,
IS2292(IPV6_2292RTHDR, IPV6_RTHDR),
IPPROTO_IPV6);
if (*mp)
mp = &(*mp)->m_next;
break;
case IPPROTO_HOPOPTS:
case IPPROTO_AH: /* is it possible? */
break;
default:
/*
* other cases have been filtered in the above.
* none will visit this case. here we supply
* the code just in case (nxt overwritten or
* other cases).
*/
m_freem(ext);
goto loopend;
}
/* proceed with the next header. */
off += elen;
nxt = ip6e->ip6e_nxt;
ip6e = NULL;
m_freem(ext);
ext = NULL;
}
loopend:
;
}
}
#undef IS2292
void
ip6_notify_pmtu(struct inpcb *inp, const struct sockaddr_in6 *dst,
uint32_t *mtu)
{
struct socket *so;
struct mbuf *m_mtu;
struct ip6_mtuinfo mtuctl;
so = inp->inp_socket;
if (mtu == NULL)
return;
KASSERT(so != NULL);
memset(&mtuctl, 0, sizeof(mtuctl)); /* zero-clear for safety */
mtuctl.ip6m_mtu = *mtu;
mtuctl.ip6m_addr = *dst;
if (sa6_recoverscope(&mtuctl.ip6m_addr))
return;
if ((m_mtu = sbcreatecontrol(&mtuctl, sizeof(mtuctl),
IPV6_PATHMTU, IPPROTO_IPV6)) == NULL)
return;
if (sbappendaddr(&so->so_rcv, (const struct sockaddr *)dst, NULL, m_mtu)
== 0) {
soroverflow(so);
m_freem(m_mtu);
} else
sorwakeup(so);
return;
}
/*
* pull single extension header from mbuf chain. returns single mbuf that
* contains the result, or NULL on error.
*/
static struct mbuf *
ip6_pullexthdr(struct mbuf *m, size_t off, int nxt)
{
struct ip6_ext ip6e;
size_t elen;
struct mbuf *n;
if (off + sizeof(ip6e) > m->m_pkthdr.len)
return NULL;
m_copydata(m, off, sizeof(ip6e), (void *)&ip6e);
if (nxt == IPPROTO_AH)
elen = (ip6e.ip6e_len + 2) << 2;
else
elen = (ip6e.ip6e_len + 1) << 3;
if (off + elen > m->m_pkthdr.len)
return NULL;
MGET(n, M_DONTWAIT, MT_DATA);
if (n && elen >= MLEN) {
MCLGET(n, M_DONTWAIT);
if ((n->m_flags & M_EXT) == 0) {
m_free(n);
n = NULL;
}
}
if (!n)
return NULL;
n->m_len = 0;
if (elen >= M_TRAILINGSPACE(n)) {
m_free(n);
return NULL;
}
m_copydata(m, off, elen, mtod(n, void *));
n->m_len = elen;
return n;
}
/*
* Get offset to the previous header followed by the header
* currently processed.
*/
int
ip6_get_prevhdr(struct mbuf *m, int off)
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
if (off == sizeof(struct ip6_hdr)) {
return offsetof(struct ip6_hdr, ip6_nxt);
} else if (off < sizeof(struct ip6_hdr)) {
panic("%s: off < sizeof(struct ip6_hdr)", __func__);
} else {
int len, nlen, nxt;
struct ip6_ext ip6e;
nxt = ip6->ip6_nxt;
len = sizeof(struct ip6_hdr);
nlen = 0;
while (len < off) {
m_copydata(m, len, sizeof(ip6e), &ip6e);
switch (nxt) {
case IPPROTO_FRAGMENT:
nlen = sizeof(struct ip6_frag);
break;
case IPPROTO_AH:
nlen = (ip6e.ip6e_len + 2) << 2;
break;
default:
nlen = (ip6e.ip6e_len + 1) << 3;
break;
}
len += nlen;
nxt = ip6e.ip6e_nxt;
}
return (len - nlen);
}
}
/*
* get next header offset. m will be retained.
*/
int
ip6_nexthdr(struct mbuf *m, int off, int proto, int *nxtp)
{
struct ip6_hdr ip6;
struct ip6_ext ip6e;
struct ip6_frag fh;
/* just in case */
if (m == NULL)
panic("%s: m == NULL", __func__);
if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off)
return -1;
switch (proto) {
case IPPROTO_IPV6:
/* do not chase beyond intermediate IPv6 headers */
if (off != 0)
return -1;
if (m->m_pkthdr.len < off + sizeof(ip6))
return -1;
m_copydata(m, off, sizeof(ip6), (void *)&ip6);
if (nxtp)
*nxtp = ip6.ip6_nxt;
off += sizeof(ip6);
return off;
case IPPROTO_FRAGMENT:
/*
* terminate parsing if it is not the first fragment,
* it does not make sense to parse through it.
*/
if (m->m_pkthdr.len < off + sizeof(fh))
return -1;
m_copydata(m, off, sizeof(fh), (void *)&fh);
if ((fh.ip6f_offlg & IP6F_OFF_MASK) != 0)
return -1;
if (nxtp)
*nxtp = fh.ip6f_nxt;
off += sizeof(struct ip6_frag);
return off;
case IPPROTO_AH:
if (m->m_pkthdr.len < off + sizeof(ip6e))
return -1;
m_copydata(m, off, sizeof(ip6e), (void *)&ip6e);
if (nxtp)
*nxtp = ip6e.ip6e_nxt;
off += (ip6e.ip6e_len + 2) << 2;
if (m->m_pkthdr.len < off)
return -1;
return off;
case IPPROTO_HOPOPTS:
case IPPROTO_ROUTING:
case IPPROTO_DSTOPTS:
if (m->m_pkthdr.len < off + sizeof(ip6e))
return -1;
m_copydata(m, off, sizeof(ip6e), (void *)&ip6e);
if (nxtp)
*nxtp = ip6e.ip6e_nxt;
off += (ip6e.ip6e_len + 1) << 3;
if (m->m_pkthdr.len < off)
return -1;
return off;
case IPPROTO_NONE:
case IPPROTO_ESP:
case IPPROTO_IPCOMP:
/* give up */
return -1;
default:
return -1;
}
}
/*
* get offset for the last header in the chain. m will be kept untainted.
*/
int
ip6_lasthdr(struct mbuf *m, int off, int proto, int *nxtp)
{
int newoff;
int nxt;
if (!nxtp) {
nxt = -1;
nxtp = &nxt;
}
for (;;) {
newoff = ip6_nexthdr(m, off, proto, nxtp);
if (newoff < 0)
return off;
else if (newoff < off)
return -1; /* invalid */
else if (newoff == off)
return newoff;
off = newoff;
proto = *nxtp;
}
}
static struct m_tag *
ip6_addaux(struct mbuf *m)
{
struct m_tag *mtag;
mtag = m_tag_find(m, PACKET_TAG_INET6);
if (!mtag) {
mtag = m_tag_get(PACKET_TAG_INET6, sizeof(struct ip6aux),
M_NOWAIT);
if (mtag) {
m_tag_prepend(m, mtag);
memset(mtag + 1, 0, sizeof(struct ip6aux));
}
}
return mtag;
}
static struct m_tag *
ip6_findaux(struct mbuf *m)
{
struct m_tag *mtag;
mtag = m_tag_find(m, PACKET_TAG_INET6);
return mtag;
}
static void
ip6_delaux(struct mbuf *m)
{
struct m_tag *mtag;
mtag = m_tag_find(m, PACKET_TAG_INET6);
if (mtag)
m_tag_delete(m, mtag);
}
/*
* System control for IP6
*/
const u_char inet6ctlerrmap[PRC_NCMDS] = {
0, 0, 0, 0,
0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
EMSGSIZE, EHOSTUNREACH, 0, 0,
0, 0, 0, 0,
ENOPROTOOPT
};
extern int sysctl_net_inet6_addrctlpolicy(SYSCTLFN_ARGS);
static int
sysctl_net_inet6_ip6_stats(SYSCTLFN_ARGS)
{
return (NETSTAT_SYSCTL(ip6stat_percpu, IP6_NSTATS));
}
static void
sysctl_net_inet6_ip6_setup(struct sysctllog **clog)
{
const struct sysctlnode *ip6_node;
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "inet6",
SYSCTL_DESCR("PF_INET6 related settings"),
NULL, 0, NULL, 0,
CTL_NET, PF_INET6, CTL_EOL);
sysctl_createv(clog, 0, NULL, &ip6_node,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "ip6",
SYSCTL_DESCR("IPv6 related settings"),
NULL, 0, NULL, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "forwarding",
SYSCTL_DESCR("Enable forwarding of INET6 datagrams"),
NULL, 0, &ip6_forwarding, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_FORWARDING, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "redirect",
SYSCTL_DESCR("Enable sending of ICMPv6 redirect messages"),
NULL, 0, &ip6_sendredirects, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_SENDREDIRECTS, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "hlim",
SYSCTL_DESCR("Hop limit for an INET6 datagram"),
NULL, 0, &ip6_defhlim, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_DEFHLIM, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "maxfragpackets",
SYSCTL_DESCR("Maximum number of fragments to buffer "
"for reassembly"),
NULL, 0, &ip6_maxfragpackets, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_MAXFRAGPACKETS, CTL_EOL);
pktq_sysctl_setup(ip6_pktq, clog, ip6_node, IPV6CTL_IFQ);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "keepfaith",
SYSCTL_DESCR("Activate faith interface"),
NULL, 0, &ip6_keepfaith, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_KEEPFAITH, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "log_interval",
SYSCTL_DESCR("Minimum interval between logging "
"unroutable packets"),
NULL, 0, &ip6_log_interval, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_LOG_INTERVAL, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "hdrnestlimit",
SYSCTL_DESCR("Maximum number of nested IPv6 headers"),
NULL, 0, &ip6_hdrnestlimit, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_HDRNESTLIMIT, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "dad_count",
SYSCTL_DESCR("Number of Duplicate Address Detection "
"probes to send"),
NULL, 0, &ip6_dad_count, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_DAD_COUNT, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "auto_flowlabel",
SYSCTL_DESCR("Assign random IPv6 flow labels"),
NULL, 0, &ip6_auto_flowlabel, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_AUTO_FLOWLABEL, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "defmcasthlim",
SYSCTL_DESCR("Default multicast hop limit"),
NULL, 0, &ip6_defmcasthlim, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_DEFMCASTHLIM, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_STRING, "kame_version",
SYSCTL_DESCR("KAME Version"),
NULL, 0, __UNCONST(__KAME_VERSION), 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_KAME_VERSION, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "use_deprecated",
SYSCTL_DESCR("Allow use of deprecated addresses as "
"source addresses"),
NULL, 0, &ip6_use_deprecated, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_USE_DEPRECATED, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT
#ifndef INET6_BINDV6ONLY
|CTLFLAG_READWRITE,
#endif
CTLTYPE_INT, "v6only",
SYSCTL_DESCR("Disallow PF_INET6 sockets from connecting "
"to PF_INET sockets"),
NULL, 0, &ip6_v6only, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_V6ONLY, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "anonportmin",
SYSCTL_DESCR("Lowest ephemeral port number to assign"),
sysctl_net_inet_ip_ports, 0, &ip6_anonportmin, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_ANONPORTMIN, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "anonportmax",
SYSCTL_DESCR("Highest ephemeral port number to assign"),
sysctl_net_inet_ip_ports, 0, &ip6_anonportmax, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_ANONPORTMAX, CTL_EOL);
#ifndef IPNOPRIVPORTS
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "lowportmin",
SYSCTL_DESCR("Lowest privileged ephemeral port number "
"to assign"),
sysctl_net_inet_ip_ports, 0, &ip6_lowportmin, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_LOWPORTMIN, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "lowportmax",
SYSCTL_DESCR("Highest privileged ephemeral port number "
"to assign"),
sysctl_net_inet_ip_ports, 0, &ip6_lowportmax, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_LOWPORTMAX, CTL_EOL);
#endif /* IPNOPRIVPORTS */
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "auto_linklocal",
SYSCTL_DESCR("Default value of per-interface flag for "
"adding an IPv6 link-local address to "
"interfaces when attached"),
NULL, 0, &ip6_auto_linklocal, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_AUTO_LINKLOCAL, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READONLY,
CTLTYPE_STRUCT, "addctlpolicy",
SYSCTL_DESCR("Return the current address control"
" policy"),
sysctl_net_inet6_addrctlpolicy, 0, NULL, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_ADDRCTLPOLICY, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "prefer_tempaddr",
SYSCTL_DESCR("Prefer temporary address as source "
"address"),
NULL, 0, &ip6_prefer_tempaddr, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "maxfrags",
SYSCTL_DESCR("Maximum fragments in reassembly queue"),
NULL, 0, &ip6_maxfrags, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_MAXFRAGS, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_STRUCT, "stats",
SYSCTL_DESCR("IPv6 statistics"),
sysctl_net_inet6_ip6_stats, 0, NULL, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_STATS, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "use_defaultzone",
SYSCTL_DESCR("Whether to use the default scope zones"),
NULL, 0, &ip6_use_defzone, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_USE_DEFAULTZONE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "mcast_pmtu",
SYSCTL_DESCR("Enable pMTU discovery for multicast packet"),
NULL, 0, &ip6_mcast_pmtu, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
CTL_CREATE, CTL_EOL);
/* anonportalgo RFC6056 subtree */
const struct sysctlnode *portalgo_node;
sysctl_createv(clog, 0, NULL, &portalgo_node,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "anonportalgo",
SYSCTL_DESCR("Anonymous port algorithm selection (RFC 6056)"),
NULL, 0, NULL, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6, CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, &portalgo_node, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_STRING, "available",
SYSCTL_DESCR("available algorithms"),
sysctl_portalgo_available, 0, NULL, PORTALGO_MAXLEN,
CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, &portalgo_node, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_STRING, "selected",
SYSCTL_DESCR("selected algorithm"),
sysctl_portalgo_selected6, 0, NULL, PORTALGO_MAXLEN,
CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, &portalgo_node, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_STRUCT, "reserve",
SYSCTL_DESCR("bitmap of reserved ports"),
sysctl_portalgo_reserve6, 0, NULL, 0,
CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "neighborgcthresh",
SYSCTL_DESCR("Maximum number of entries in neighbor"
" cache"),
NULL, 1, &ip6_neighborgcthresh, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "maxdynroutes",
SYSCTL_DESCR("Maximum number of routes created via"
" redirect"),
NULL, 1, &ip6_maxdynroutes, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "param_rt_msg",
SYSCTL_DESCR("How to send parameter changing"
" routing message"),
NULL, 0, &ip6_param_rt_msg, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
CTL_CREATE, CTL_EOL);
}
void
ip6_statinc(u_int stat)
{
KASSERT(stat < IP6_NSTATS);
IP6_STATINC(stat);
}