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/* $OpenBSD: ip6_output.c,v 1.291 2024/04/17 20:48:51 bluhm Exp $ */
/* $KAME: ip6_output.c,v 1.172 2001/03/25 09:55:56 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, 1990, 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_output.c 8.3 (Berkeley) 1/21/94
*/
#include "pf.h"
#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/errno.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_enc.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet/udp.h>
#include <netinet/tcp.h>
#include <netinet/ip_var.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
#include <netinet/udp_var.h>
#include <netinet6/in6_var.h>
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/nd6.h>
#include <crypto/idgen.h>
#if NPF > 0
#include <net/pfvar.h>
#endif
#ifdef IPSEC
#include <netinet/ip_ipsp.h>
#include <netinet/ip_ah.h>
#include <netinet/ip_esp.h>
#ifdef ENCDEBUG
#define DPRINTF(fmt, args...) \
do { \
if (encdebug) \
printf("%s: " fmt "\n", __func__, ## args); \
} while (0)
#else
#define DPRINTF(fmt, args...) \
do { } while (0)
#endif
#endif /* IPSEC */
struct ip6_exthdrs {
struct mbuf *ip6e_ip6;
struct mbuf *ip6e_hbh;
struct mbuf *ip6e_dest1;
struct mbuf *ip6e_rthdr;
struct mbuf *ip6e_dest2;
};
int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **, int, int);
int ip6_getpcbopt(struct ip6_pktopts *, int, struct mbuf *);
int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *, int, int, int);
int ip6_setmoptions(int, struct ip6_moptions **, struct mbuf *, unsigned int);
int ip6_getmoptions(int, struct ip6_moptions *, struct mbuf *);
int ip6_copyexthdr(struct mbuf **, caddr_t, int);
int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
struct ip6_frag **);
int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
int ip6_getpmtu(struct rtentry *, struct ifnet *, u_long *);
int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *);
static __inline u_int16_t __attribute__((__unused__))
in6_cksum_phdr(const struct in6_addr *, const struct in6_addr *,
u_int32_t, u_int32_t);
void in6_delayed_cksum(struct mbuf *, u_int8_t);
int ip6_output_ipsec_pmtu_update(struct tdb *, struct route *,
struct in6_addr *, int, int, int);
/* Context for non-repeating IDs */
struct idgen32_ctx ip6_id_ctx;
/*
* IP6 output. The packet in mbuf chain m contains a skeletal IP6
* header (with pri, len, nxt, hlim, src, dst).
* This function may modify ver and hlim only.
* The mbuf chain containing the packet will be freed.
* The mbuf opt, if present, will not be freed.
*
* type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int.
* We use u_long to hold largest one, * which is rt_mtu.
*/
int
ip6_output(struct mbuf *m, struct ip6_pktopts *opt, struct route *ro,
int flags, struct ip6_moptions *im6o, const struct ipsec_level *seclevel)
{
struct ip6_hdr *ip6;
struct ifnet *ifp = NULL;
struct mbuf_list ml;
int hlen, tlen;
struct route iproute;
struct rtentry *rt = NULL;
struct sockaddr_in6 *dst;
int error = 0;
u_long mtu;
int dontfrag;
u_int16_t src_scope, dst_scope;
u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
struct ip6_exthdrs exthdrs;
struct in6_addr finaldst;
struct route *ro_pmtu = NULL;
int hdrsplit = 0;
u_int8_t sproto = 0;
u_char nextproto;
#ifdef IPSEC
struct tdb *tdb = NULL;
#endif /* IPSEC */
ip6 = mtod(m, struct ip6_hdr *);
finaldst = ip6->ip6_dst;
#define MAKE_EXTHDR(hp, mp) \
do { \
if (hp) { \
struct ip6_ext *eh = (struct ip6_ext *)(hp); \
error = ip6_copyexthdr((mp), (caddr_t)(hp), \
((eh)->ip6e_len + 1) << 3); \
if (error) \
goto freehdrs; \
} \
} while (0)
bzero(&exthdrs, sizeof(exthdrs));
if (opt) {
/* Hop-by-Hop options header */
MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
/* Destination options header(1st part) */
MAKE_EXTHDR(opt->ip6po_dest1, &exthdrs.ip6e_dest1);
/* Routing header */
MAKE_EXTHDR(opt->ip6po_rthdr, &exthdrs.ip6e_rthdr);
/* Destination options header(2nd part) */
MAKE_EXTHDR(opt->ip6po_dest2, &exthdrs.ip6e_dest2);
}
#ifdef IPSEC
if (ipsec_in_use || seclevel != NULL) {
error = ip6_output_ipsec_lookup(m, seclevel, &tdb);
if (error) {
/*
* -EINVAL is used to indicate that the packet should
* be silently dropped, typically because we've asked
* key management for an SA.
*/
if (error == -EINVAL) /* Should silently drop packet */
error = 0;
goto freehdrs;
}
}
#endif /* IPSEC */
/*
* Calculate the total length of the extension header chain.
* Keep the length of the unfragmentable part for fragmentation.
*/
optlen = 0;
if (exthdrs.ip6e_hbh) optlen += exthdrs.ip6e_hbh->m_len;
if (exthdrs.ip6e_dest1) optlen += exthdrs.ip6e_dest1->m_len;
if (exthdrs.ip6e_rthdr) optlen += exthdrs.ip6e_rthdr->m_len;
unfragpartlen = optlen + sizeof(struct ip6_hdr);
/* NOTE: we don't add AH/ESP length here. do that later. */
if (exthdrs.ip6e_dest2) optlen += exthdrs.ip6e_dest2->m_len;
/*
* If we need IPsec, or there is at least one extension header,
* separate IP6 header from the payload.
*/
if ((sproto || optlen) && !hdrsplit) {
if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
m = NULL;
goto freehdrs;
}
m = exthdrs.ip6e_ip6;
hdrsplit++;
}
/* adjust pointer */
ip6 = mtod(m, struct ip6_hdr *);
/* adjust mbuf packet header length */
m->m_pkthdr.len += optlen;
plen = m->m_pkthdr.len - sizeof(*ip6);
/* If this is a jumbo payload, insert a jumbo payload option. */
if (plen > IPV6_MAXPACKET) {
if (!hdrsplit) {
if ((error = ip6_splithdr(m, &exthdrs)) != 0) {
m = NULL;
goto freehdrs;
}
m = exthdrs.ip6e_ip6;
hdrsplit++;
}
/* adjust pointer */
ip6 = mtod(m, struct ip6_hdr *);
if ((error = ip6_insert_jumboopt(&exthdrs, plen)) != 0)
goto freehdrs;
ip6->ip6_plen = 0;
} else
ip6->ip6_plen = htons(plen);
/*
* Concatenate headers and fill in next header fields.
* Here we have, on "m"
* IPv6 payload
* and we insert headers accordingly. Finally, we should be getting:
* IPv6 hbh dest1 rthdr ah* [esp* dest2 payload]
*
* during the header composing process, "m" points to IPv6 header.
* "mprev" points to an extension header prior to esp.
*/
{
u_char *nexthdrp = &ip6->ip6_nxt;
struct mbuf *mprev = m;
/*
* we treat dest2 specially. this makes IPsec processing
* much easier. the goal here is to make mprev point the
* mbuf prior to dest2.
*
* result: IPv6 dest2 payload
* m and mprev will point to IPv6 header.
*/
if (exthdrs.ip6e_dest2) {
if (!hdrsplit)
panic("%s: assumption failed: hdr not split",
__func__);
exthdrs.ip6e_dest2->m_next = m->m_next;
m->m_next = exthdrs.ip6e_dest2;
*mtod(exthdrs.ip6e_dest2, u_char *) = ip6->ip6_nxt;
ip6->ip6_nxt = IPPROTO_DSTOPTS;
}
#define MAKE_CHAIN(m, mp, p, i)\
do {\
if (m) {\
if (!hdrsplit) \
panic("assumption failed: hdr not split"); \
*mtod((m), u_char *) = *(p);\
*(p) = (i);\
p = mtod((m), u_char *);\
(m)->m_next = (mp)->m_next;\
(mp)->m_next = (m);\
(mp) = (m);\
}\
} while (0)
/*
* result: IPv6 hbh dest1 rthdr dest2 payload
* m will point to IPv6 header. mprev will point to the
* extension header prior to dest2 (rthdr in the above case).
*/
MAKE_CHAIN(exthdrs.ip6e_hbh, mprev, nexthdrp, IPPROTO_HOPOPTS);
MAKE_CHAIN(exthdrs.ip6e_dest1, mprev, nexthdrp,
IPPROTO_DSTOPTS);
MAKE_CHAIN(exthdrs.ip6e_rthdr, mprev, nexthdrp,
IPPROTO_ROUTING);
}
/*
* If there is a routing header, replace the destination address field
* with the first hop of the routing header.
*/
if (exthdrs.ip6e_rthdr) {
struct ip6_rthdr *rh;
struct ip6_rthdr0 *rh0;
struct in6_addr *addr;
rh = (struct ip6_rthdr *)(mtod(exthdrs.ip6e_rthdr,
struct ip6_rthdr *));
switch (rh->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
rh0 = (struct ip6_rthdr0 *)rh;
addr = (struct in6_addr *)(rh0 + 1);
ip6->ip6_dst = addr[0];
bcopy(&addr[1], &addr[0],
sizeof(struct in6_addr) * (rh0->ip6r0_segleft - 1));
addr[rh0->ip6r0_segleft - 1] = finaldst;
break;
default: /* is it possible? */
error = EINVAL;
goto bad;
}
}
/* Source address validation */
if (!(flags & IPV6_UNSPECSRC) &&
IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
/*
* XXX: we can probably assume validation in the caller, but
* we explicitly check the address here for safety.
*/
error = EOPNOTSUPP;
ip6stat_inc(ip6s_badscope);
goto bad;
}
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
error = EOPNOTSUPP;
ip6stat_inc(ip6s_badscope);
goto bad;
}
ip6stat_inc(ip6s_localout);
/*
* Route packet.
*/
#if NPF > 0
reroute:
#endif
/* initialize cached route */
if (ro == NULL) {
ro = &iproute;
ro->ro_rt = NULL;
}
ro_pmtu = ro;
if (opt && opt->ip6po_rthdr)
ro = &opt->ip6po_route;
dst = &ro->ro_dstsin6;
/*
* if specified, try to fill in the traffic class field.
* do not override if a non-zero value is already set.
* we check the diffserv field and the ecn field separately.
*/
if (opt && opt->ip6po_tclass >= 0) {
int mask = 0;
if ((ip6->ip6_flow & htonl(0xfc << 20)) == 0)
mask |= 0xfc;
if ((ip6->ip6_flow & htonl(0x03 << 20)) == 0)
mask |= 0x03;
if (mask != 0)
ip6->ip6_flow |=
htonl((opt->ip6po_tclass & mask) << 20);
}
/* fill in or override the hop limit field, if necessary. */
if (opt && opt->ip6po_hlim != -1)
ip6->ip6_hlim = opt->ip6po_hlim & 0xff;
else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
if (im6o != NULL)
ip6->ip6_hlim = im6o->im6o_hlim;
else
ip6->ip6_hlim = ip6_defmcasthlim;
}
#ifdef IPSEC
if (tdb != NULL) {
/*
* XXX what should we do if ip6_hlim == 0 and the
* packet gets tunneled?
*/
/*
* if we are source-routing, do not attempt to tunnel the
* packet just because ip6_dst is different from what tdb has.
* XXX
*/
error = ip6_output_ipsec_send(tdb, m, ro,
exthdrs.ip6e_rthdr ? 1 : 0, 0);
goto done;
}
#endif /* IPSEC */
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
struct in6_pktinfo *pi = NULL;
/*
* If the caller specify the outgoing interface
* explicitly, use it.
*/
if (opt != NULL && (pi = opt->ip6po_pktinfo) != NULL)
ifp = if_get(pi->ipi6_ifindex);
if (ifp == NULL && im6o != NULL)
ifp = if_get(im6o->im6o_ifidx);
}
if (ifp == NULL) {
rt = in6_selectroute(&ip6->ip6_dst, opt, ro,
m->m_pkthdr.ph_rtableid);
if (rt == NULL) {
ip6stat_inc(ip6s_noroute);
error = EHOSTUNREACH;
goto bad;
}
if (ISSET(rt->rt_flags, RTF_LOCAL))
ifp = if_get(rtable_loindex(m->m_pkthdr.ph_rtableid));
else
ifp = if_get(rt->rt_ifidx);
/*
* We aren't using rtisvalid() here because the UP/DOWN state
* machine is broken with some Ethernet drivers like em(4).
* As a result we might try to use an invalid cached route
* entry while an interface is being detached.
*/
if (ifp == NULL) {
ip6stat_inc(ip6s_noroute);
error = EHOSTUNREACH;
goto bad;
}
} else {
route6_cache(ro, &ip6->ip6_dst, NULL, m->m_pkthdr.ph_rtableid);
}
if (rt && (rt->rt_flags & RTF_GATEWAY) &&
!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst))
dst = satosin6(rt->rt_gateway);
if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
/* Unicast */
m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
} else {
/* Multicast */
m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
/*
* Confirm that the outgoing interface supports multicast.
*/
if ((ifp->if_flags & IFF_MULTICAST) == 0) {
ip6stat_inc(ip6s_noroute);
error = ENETUNREACH;
goto bad;
}
if ((im6o == NULL || im6o->im6o_loop) &&
in6_hasmulti(&ip6->ip6_dst, ifp)) {
/*
* If we belong to the destination multicast group
* on the outgoing interface, and the caller did not
* forbid loopback, loop back a copy.
* Can't defer TCP/UDP checksumming, do the
* computation now.
*/
in6_proto_cksum_out(m, NULL);
ip6_mloopback(ifp, m, dst);
}
#ifdef MROUTING
else {
/*
* If we are acting as a multicast router, perform
* multicast forwarding as if the packet had just
* arrived on the interface to which we are about
* to send. The multicast forwarding function
* recursively calls this function, using the
* IPV6_FORWARDING flag to prevent infinite recursion.
*
* Multicasts that are looped back by ip6_mloopback(),
* above, will be forwarded by the ip6_input() routine,
* if necessary.
*/
if (ip6_mforwarding && ip6_mrouter[ifp->if_rdomain] &&
(flags & IPV6_FORWARDING) == 0) {
if (ip6_mforward(ip6, ifp, m) != 0) {
m_freem(m);
goto done;
}
}
}
#endif
/*
* Multicasts with a hoplimit of zero may be looped back,
* above, but must not be transmitted on a network.
* Also, multicasts addressed to the loopback interface
* are not sent -- the above call to ip6_mloopback() will
* loop back a copy if this host actually belongs to the
* destination group on the loopback interface.
*/
if (ip6->ip6_hlim == 0 || (ifp->if_flags & IFF_LOOPBACK) ||
IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst)) {
m_freem(m);
goto done;
}
}
/*
* If this packet is going through a loopback interface we won't
* be able to restore its scope ID using the interface index.
*/
if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) {
if (ifp->if_flags & IFF_LOOPBACK)
src_scope = ip6->ip6_src.s6_addr16[1];
ip6->ip6_src.s6_addr16[1] = 0;
}
if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) {
if (ifp->if_flags & IFF_LOOPBACK)
dst_scope = ip6->ip6_dst.s6_addr16[1];
ip6->ip6_dst.s6_addr16[1] = 0;
}
/* Determine path MTU. */
if ((error = ip6_getpmtu(ro_pmtu->ro_rt, ifp, &mtu)) != 0)
goto bad;
/*
* The caller of this function may specify to use the minimum MTU
* in some cases.
* An advanced API option (IPV6_USE_MIN_MTU) can also override MTU
* setting. The logic is a bit complicated; by default, unicast
* packets will follow path MTU while multicast packets will be sent at
* the minimum MTU. If IP6PO_MINMTU_ALL is specified, all packets
* including unicast ones will be sent at the minimum MTU. Multicast
* packets will always be sent at the minimum MTU unless
* IP6PO_MINMTU_DISABLE is explicitly specified.
* See RFC 3542 for more details.
*/
if (mtu > IPV6_MMTU) {
if ((flags & IPV6_MINMTU))
mtu = IPV6_MMTU;
else if (opt && opt->ip6po_minmtu == IP6PO_MINMTU_ALL)
mtu = IPV6_MMTU;
else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && (opt == NULL ||
opt->ip6po_minmtu != IP6PO_MINMTU_DISABLE)) {
mtu = IPV6_MMTU;
}
}
/*
* If the outgoing packet contains a hop-by-hop options header,
* it must be examined and processed even by the source node.
* (RFC 2460, section 4.)
*/
if (exthdrs.ip6e_hbh) {
struct ip6_hbh *hbh = mtod(exthdrs.ip6e_hbh, struct ip6_hbh *);
u_int32_t rtalert; /* returned value is ignored */
u_int32_t plen = 0; /* no more than 1 jumbo payload option! */
m->m_pkthdr.ph_ifidx = ifp->if_index;
if (ip6_process_hopopts(&m, (u_int8_t *)(hbh + 1),
((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
&rtalert, &plen) < 0) {
/* m was already freed at this point */
error = EINVAL;/* better error? */
goto done;
}
m->m_pkthdr.ph_ifidx = 0;
}
#if NPF > 0
if (pf_test(AF_INET6, PF_OUT, ifp, &m) != PF_PASS) {
error = EACCES;
m_freem(m);
goto done;
}
if (m == NULL)
goto done;
ip6 = mtod(m, struct ip6_hdr *);
if ((m->m_pkthdr.pf.flags & (PF_TAG_REROUTE | PF_TAG_GENERATED)) ==
(PF_TAG_REROUTE | PF_TAG_GENERATED)) {
/* already rerun the route lookup, go on */
m->m_pkthdr.pf.flags &= ~(PF_TAG_GENERATED | PF_TAG_REROUTE);
} else if (m->m_pkthdr.pf.flags & PF_TAG_REROUTE) {
/* tag as generated to skip over pf_test on rerun */
m->m_pkthdr.pf.flags |= PF_TAG_GENERATED;
finaldst = ip6->ip6_dst;
if (ro == &iproute)
rtfree(ro->ro_rt);
ro = NULL;
if_put(ifp); /* drop reference since destination changed */
ifp = NULL;
goto reroute;
}
#endif
/*
* If the packet is not going on the wire it can be destined
* to any local address. In this case do not clear its scopes
* to let ip6_input() find a matching local route.
*/
if (ifp->if_flags & IFF_LOOPBACK) {
if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src))
ip6->ip6_src.s6_addr16[1] = src_scope;
if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst))
ip6->ip6_dst.s6_addr16[1] = dst_scope;
}
/*
* Send the packet to the outgoing interface.
* If necessary, do IPv6 fragmentation before sending.
*
* the logic here is rather complex:
* 1: normal case (dontfrag == 0)
* 1-a: send as is if tlen <= path mtu
* 1-b: fragment if tlen > path mtu
*
* 2: if user asks us not to fragment (dontfrag == 1)
* 2-a: send as is if tlen <= interface mtu
* 2-b: error if tlen > interface mtu
*/
tlen = ISSET(m->m_pkthdr.csum_flags, M_TCP_TSO) ?
m->m_pkthdr.ph_mss : m->m_pkthdr.len;
if (ISSET(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT)) {
CLR(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT);
dontfrag = 1;
} else if (opt && ISSET(opt->ip6po_flags, IP6PO_DONTFRAG))
dontfrag = 1;
else
dontfrag = 0;
if (dontfrag && tlen > ifp->if_mtu) { /* case 2-b */
#ifdef IPSEC
if (ip_mtudisc)
ipsec_adjust_mtu(m, mtu);
#endif
error = EMSGSIZE;
goto bad;
}
/*
* transmit packet without fragmentation
*/
if (dontfrag || tlen <= mtu) { /* case 1-a and 2-a */
error = if_output_tso(ifp, &m, sin6tosa(dst), ro->ro_rt,
ifp->if_mtu);
if (error || m == NULL)
goto done;
goto bad; /* should not happen */
}
/*
* try to fragment the packet. case 1-b
*/
if (mtu < IPV6_MMTU) {
/* path MTU cannot be less than IPV6_MMTU */
error = EMSGSIZE;
goto bad;
} else if (ip6->ip6_plen == 0) {
/* jumbo payload cannot be fragmented */
error = EMSGSIZE;
goto bad;
}
/*
* Too large for the destination or interface;
* fragment if possible.
* Must be able to put at least 8 bytes per fragment.
*/
hlen = unfragpartlen;
if (mtu > IPV6_MAXPACKET)
mtu = IPV6_MAXPACKET;
/*
* If we are doing fragmentation, we can't defer TCP/UDP
* checksumming; compute the checksum and clear the flag.
*/
in6_proto_cksum_out(m, NULL);
/*
* Change the next header field of the last header in the
* unfragmentable part.
*/
if (exthdrs.ip6e_rthdr) {
nextproto = *mtod(exthdrs.ip6e_rthdr, u_char *);
*mtod(exthdrs.ip6e_rthdr, u_char *) = IPPROTO_FRAGMENT;
} else if (exthdrs.ip6e_dest1) {
nextproto = *mtod(exthdrs.ip6e_dest1, u_char *);
*mtod(exthdrs.ip6e_dest1, u_char *) = IPPROTO_FRAGMENT;
} else if (exthdrs.ip6e_hbh) {
nextproto = *mtod(exthdrs.ip6e_hbh, u_char *);
*mtod(exthdrs.ip6e_hbh, u_char *) = IPPROTO_FRAGMENT;
} else {
nextproto = ip6->ip6_nxt;
ip6->ip6_nxt = IPPROTO_FRAGMENT;
}
if ((error = ip6_fragment(m, &ml, hlen, nextproto, mtu)) ||
(error = if_output_ml(ifp, &ml, sin6tosa(dst), ro->ro_rt)))
goto done;
ip6stat_inc(ip6s_fragmented);
goto done;
freehdrs:
m_freem(exthdrs.ip6e_hbh); /* m_freem will check if mbuf is 0 */
m_freem(exthdrs.ip6e_dest1);
m_freem(exthdrs.ip6e_rthdr);
m_freem(exthdrs.ip6e_dest2);
bad:
m_freem(m);
done:
if (ro == &iproute)
rtfree(ro->ro_rt);
else if (ro_pmtu == &iproute)
rtfree(ro_pmtu->ro_rt);
if_put(ifp);
#ifdef IPSEC
tdb_unref(tdb);
#endif /* IPSEC */
return (error);
}
int
ip6_fragment(struct mbuf *m0, struct mbuf_list *ml, int hlen, u_char nextproto,
u_long mtu)
{
struct ip6_hdr *ip6;
u_int32_t id;
int tlen, len, off;
int error;
ml_init(ml);
ip6 = mtod(m0, struct ip6_hdr *);
tlen = m0->m_pkthdr.len;
len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
if (len < 8) {
error = EMSGSIZE;
goto bad;
}
id = htonl(ip6_randomid());
/*
* Loop through length of payload,
* make new header and copy data of each part and link onto chain.
*/
for (off = hlen; off < tlen; off += len) {
struct mbuf *m;
struct mbuf *mlast;
struct ip6_hdr *mhip6;
struct ip6_frag *ip6f;
MGETHDR(m, M_DONTWAIT, MT_HEADER);
if (m == NULL) {
error = ENOBUFS;
goto bad;
}
ml_enqueue(ml, m);
if ((error = m_dup_pkthdr(m, m0, M_DONTWAIT)) != 0)
goto bad;
m->m_data += max_linkhdr;
mhip6 = mtod(m, struct ip6_hdr *);
*mhip6 = *ip6;
m->m_len = sizeof(struct ip6_hdr);
if ((error = ip6_insertfraghdr(m0, m, hlen, &ip6f)) != 0)
goto bad;
ip6f->ip6f_offlg = htons((off - hlen) & ~7);
if (off + len >= tlen)
len = tlen - off;
else
ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
m->m_pkthdr.len = hlen + sizeof(struct ip6_frag) + len;
mhip6->ip6_plen = htons(m->m_pkthdr.len -
sizeof(struct ip6_hdr));
for (mlast = m; mlast->m_next; mlast = mlast->m_next)
;
mlast->m_next = m_copym(m0, off, len, M_DONTWAIT);
if (mlast->m_next == NULL) {
error = ENOBUFS;
goto bad;
}
ip6f->ip6f_reserved = 0;
ip6f->ip6f_ident = id;
ip6f->ip6f_nxt = nextproto;
}
ip6stat_add(ip6s_ofragments, ml_len(ml));
m_freem(m0);
return (0);
bad:
ip6stat_inc(ip6s_odropped);
ml_purge(ml);
m_freem(m0);
return (error);
}
int
ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
{
struct mbuf *m;
if (hlen > MCLBYTES)
return (ENOBUFS); /* XXX */
MGET(m, M_DONTWAIT, MT_DATA);
if (!m)
return (ENOBUFS);
if (hlen > MLEN) {
MCLGET(m, M_DONTWAIT);
if ((m->m_flags & M_EXT) == 0) {
m_free(m);
return (ENOBUFS);
}
}
m->m_len = hlen;
if (hdr)
memcpy(mtod(m, caddr_t), hdr, hlen);
*mp = m;
return (0);
}
/*
* Insert jumbo payload option.
*/
int
ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
{
struct mbuf *mopt;
u_int8_t *optbuf;
u_int32_t v;
#define JUMBOOPTLEN 8 /* length of jumbo payload option and padding */
/*
* If there is no hop-by-hop options header, allocate new one.
* If there is one but it doesn't have enough space to store the
* jumbo payload option, allocate a cluster to store the whole options.
* Otherwise, use it to store the options.
*/
if (exthdrs->ip6e_hbh == 0) {
MGET(mopt, M_DONTWAIT, MT_DATA);
if (mopt == NULL)
return (ENOBUFS);
mopt->m_len = JUMBOOPTLEN;
optbuf = mtod(mopt, u_int8_t *);
optbuf[1] = 0; /* = ((JUMBOOPTLEN) >> 3) - 1 */
exthdrs->ip6e_hbh = mopt;
} else {
struct ip6_hbh *hbh;
mopt = exthdrs->ip6e_hbh;
if (m_trailingspace(mopt) < JUMBOOPTLEN) {
/*
* XXX assumption:
* - exthdrs->ip6e_hbh is not referenced from places
* other than exthdrs.
* - exthdrs->ip6e_hbh is not an mbuf chain.
*/
int oldoptlen = mopt->m_len;
struct mbuf *n;
/*
* XXX: give up if the whole (new) hbh header does
* not fit even in an mbuf cluster.
*/
if (oldoptlen + JUMBOOPTLEN > MCLBYTES)
return (ENOBUFS);
/*
* As a consequence, we must always prepare a cluster
* at this point.
*/
MGET(n, M_DONTWAIT, MT_DATA);
if (n) {
MCLGET(n, M_DONTWAIT);
if ((n->m_flags & M_EXT) == 0) {
m_freem(n);
n = NULL;
}
}
if (!n)
return (ENOBUFS);
n->m_len = oldoptlen + JUMBOOPTLEN;
memcpy(mtod(n, caddr_t), mtod(mopt, caddr_t),
oldoptlen);
optbuf = mtod(n, u_int8_t *) + oldoptlen;
m_freem(mopt);
mopt = exthdrs->ip6e_hbh = n;
} else {
optbuf = mtod(mopt, u_int8_t *) + mopt->m_len;
mopt->m_len += JUMBOOPTLEN;
}
optbuf[0] = IP6OPT_PADN;
optbuf[1] = 0;
/*
* Adjust the header length according to the pad and
* the jumbo payload option.
*/
hbh = mtod(mopt, struct ip6_hbh *);
hbh->ip6h_len += (JUMBOOPTLEN >> 3);
}
/* fill in the option. */
optbuf[2] = IP6OPT_JUMBO;
optbuf[3] = 4;
v = (u_int32_t)htonl(plen + JUMBOOPTLEN);
memcpy(&optbuf[4], &v, sizeof(u_int32_t));
/* finally, adjust the packet header length */
exthdrs->ip6e_ip6->m_pkthdr.len += JUMBOOPTLEN;
return (0);
#undef JUMBOOPTLEN
}
/*
* Insert fragment header and copy unfragmentable header portions.
*/
int
ip6_insertfraghdr(struct mbuf *m0, struct mbuf *m, int hlen,
struct ip6_frag **frghdrp)
{
struct mbuf *n, *mlast;
if (hlen > sizeof(struct ip6_hdr)) {
n = m_copym(m0, sizeof(struct ip6_hdr),
hlen - sizeof(struct ip6_hdr), M_DONTWAIT);
if (n == NULL)
return (ENOBUFS);
m->m_next = n;
} else
n = m;
/* Search for the last mbuf of unfragmentable part. */
for (mlast = n; mlast->m_next; mlast = mlast->m_next)
;
if ((mlast->m_flags & M_EXT) == 0 &&
m_trailingspace(mlast) >= sizeof(struct ip6_frag)) {
/* use the trailing space of the last mbuf for fragment hdr */
*frghdrp = (struct ip6_frag *)(mtod(mlast, caddr_t) +
mlast->m_len);
mlast->m_len += sizeof(struct ip6_frag);
m->m_pkthdr.len += sizeof(struct ip6_frag);
} else {
/* allocate a new mbuf for the fragment header */
struct mbuf *mfrg;
MGET(mfrg, M_DONTWAIT, MT_DATA);
if (mfrg == NULL)
return (ENOBUFS);
mfrg->m_len = sizeof(struct ip6_frag);
*frghdrp = mtod(mfrg, struct ip6_frag *);
mlast->m_next = mfrg;
}
return (0);
}
int
ip6_getpmtu(struct rtentry *rt, struct ifnet *ifp, u_long *mtup)
{
u_int32_t mtu = 0;
int error = 0;
if (rt != NULL) {
mtu = rt->rt_mtu;
if (mtu == 0)
mtu = ifp->if_mtu;
else if (mtu < IPV6_MMTU) {
/* RFC8021 IPv6 Atomic Fragments Considered Harmful */
mtu = IPV6_MMTU;
} else if (mtu > ifp->if_mtu) {
/*
* The MTU on the route is larger than the MTU on
* the interface! This shouldn't happen, unless the
* MTU of the interface has been changed after the
* interface was brought up. Change the MTU in the
* route to match the interface MTU (as long as the
* field isn't locked).
*/
mtu = ifp->if_mtu;
if (!(rt->rt_locks & RTV_MTU))
rt->rt_mtu = mtu;
}
} else {
mtu = ifp->if_mtu;
}
*mtup = mtu;
return (error);
}
/*
* IP6 socket option processing.
*/
int
ip6_ctloutput(int op, struct socket *so, int level, int optname,
struct mbuf *m)
{
int privileged, optdatalen, uproto;
void *optdata;
struct inpcb *inp = sotoinpcb(so);
int error, optval;
struct proc *p = curproc; /* For IPsec and rdomain */
u_int rtableid, rtid = 0;
error = optval = 0;
privileged = (inp->inp_socket->so_state & SS_PRIV);
uproto = (int)so->so_proto->pr_protocol;
if (level != IPPROTO_IPV6)
return (EINVAL);
rtableid = p->p_p->ps_rtableid;
switch (op) {
case PRCO_SETOPT:
switch (optname) {
/*
* Use of some Hop-by-Hop options or some
* Destination options, might require special
* privilege. That is, normal applications
* (without special privilege) might be forbidden
* from setting certain options in outgoing packets,
* and might never see certain options in received
* packets. [RFC 2292 Section 6]
* KAME specific note:
* KAME prevents non-privileged users from sending or
* receiving ANY hbh/dst options in order to avoid
* overhead of parsing options in the kernel.
*/
case IPV6_RECVHOPOPTS:
case IPV6_RECVDSTOPTS:
if (!privileged) {
error = EPERM;
break;
}
/* FALLTHROUGH */
case IPV6_UNICAST_HOPS:
case IPV6_MINHOPCOUNT:
case IPV6_HOPLIMIT:
case IPV6_RECVPKTINFO:
case IPV6_RECVHOPLIMIT:
case IPV6_RECVRTHDR:
case IPV6_RECVPATHMTU:
case IPV6_RECVTCLASS:
case IPV6_V6ONLY:
case IPV6_AUTOFLOWLABEL:
case IPV6_RECVDSTPORT:
if (m == NULL || m->m_len != sizeof(int)) {
error = EINVAL;
break;
}
optval = *mtod(m, int *);
switch (optname) {
case IPV6_UNICAST_HOPS:
if (optval < -1 || optval >= 256)
error = EINVAL;
else {
/* -1 = kernel default */
inp->inp_hops = optval;
}
break;
case IPV6_MINHOPCOUNT:
if (optval < 0 || optval > 255)
error = EINVAL;
else
inp->inp_ip6_minhlim = optval;
break;
#define OPTSET(bit) \
do { \
if (optval) \
inp->inp_flags |= (bit); \
else \
inp->inp_flags &= ~(bit); \
} while (/*CONSTCOND*/ 0)
#define OPTBIT(bit) (inp->inp_flags & (bit) ? 1 : 0)
case IPV6_RECVPKTINFO:
OPTSET(IN6P_PKTINFO);
break;
case IPV6_HOPLIMIT:
{
struct ip6_pktopts **optp;
optp = &inp->inp_outputopts6;
error = ip6_pcbopt(IPV6_HOPLIMIT,
(u_char *)&optval, sizeof(optval), optp,
privileged, uproto);
break;
}
case IPV6_RECVHOPLIMIT:
OPTSET(IN6P_HOPLIMIT);
break;
case IPV6_RECVHOPOPTS:
OPTSET(IN6P_HOPOPTS);
break;
case IPV6_RECVDSTOPTS:
OPTSET(IN6P_DSTOPTS);
break;
case IPV6_RECVRTHDR:
OPTSET(IN6P_RTHDR);
break;
case IPV6_RECVPATHMTU:
/*
* We ignore this option for TCP
* sockets.
* (RFC3542 leaves this case
* unspecified.)
*/
if (uproto != IPPROTO_TCP)
OPTSET(IN6P_MTU);
break;
case IPV6_V6ONLY:
/*
* make setsockopt(IPV6_V6ONLY)
* available only prior to bind(2).
* see ipng mailing list, Jun 22 2001.
*/
if (inp->inp_lport || !IN6_IS_ADDR_UNSPECIFIED(
&inp->inp_laddr6)) {
error = EINVAL;
break;
}
/* No support for IPv4-mapped addresses. */
if (!optval)
error = EINVAL;
else
error = 0;
break;
case IPV6_RECVTCLASS:
OPTSET(IN6P_TCLASS);
break;
case IPV6_AUTOFLOWLABEL:
OPTSET(IN6P_AUTOFLOWLABEL);
break;
case IPV6_RECVDSTPORT:
OPTSET(IN6P_RECVDSTPORT);
break;
}
break;
case IPV6_TCLASS:
case IPV6_DONTFRAG:
case IPV6_USE_MIN_MTU:
if (m == NULL || m->m_len != sizeof(optval)) {
error = EINVAL;
break;
}
optval = *mtod(m, int *);
{
struct ip6_pktopts **optp;
optp = &inp->inp_outputopts6;
error = ip6_pcbopt(optname, (u_char *)&optval,
sizeof(optval), optp, privileged, uproto);
break;
}
case IPV6_PKTINFO:
case IPV6_HOPOPTS:
case IPV6_RTHDR:
case IPV6_DSTOPTS:
case IPV6_RTHDRDSTOPTS:
{
/* new advanced API (RFC3542) */
u_char *optbuf;
int optbuflen;
struct ip6_pktopts **optp;
if (m && m->m_next) {
error = EINVAL; /* XXX */
break;
}
if (m) {
optbuf = mtod(m, u_char *);
optbuflen = m->m_len;
} else {
optbuf = NULL;
optbuflen = 0;
}
optp = &inp->inp_outputopts6;
error = ip6_pcbopt(optname, optbuf, optbuflen, optp,
privileged, uproto);
break;
}
#undef OPTSET
case IPV6_MULTICAST_IF:
case IPV6_MULTICAST_HOPS:
case IPV6_MULTICAST_LOOP:
case IPV6_JOIN_GROUP:
case IPV6_LEAVE_GROUP:
error = ip6_setmoptions(optname,
&inp->inp_moptions6,
m, inp->inp_rtableid);
break;
case IPV6_PORTRANGE:
if (m == NULL || m->m_len != sizeof(int)) {
error = EINVAL;
break;
}
optval = *mtod(m, int *);
switch (optval) {
case IPV6_PORTRANGE_DEFAULT:
inp->inp_flags &= ~(IN6P_LOWPORT);
inp->inp_flags &= ~(IN6P_HIGHPORT);
break;
case IPV6_PORTRANGE_HIGH:
inp->inp_flags &= ~(IN6P_LOWPORT);
inp->inp_flags |= IN6P_HIGHPORT;
break;
case IPV6_PORTRANGE_LOW:
inp->inp_flags &= ~(IN6P_HIGHPORT);
inp->inp_flags |= IN6P_LOWPORT;
break;
default:
error = EINVAL;
break;
}
break;
case IPSEC6_OUTSA:
error = EINVAL;
break;
case IPV6_AUTH_LEVEL:
case IPV6_ESP_TRANS_LEVEL:
case IPV6_ESP_NETWORK_LEVEL:
case IPV6_IPCOMP_LEVEL:
#ifndef IPSEC
error = EINVAL;
#else
if (m == NULL || m->m_len != sizeof(int)) {
error = EINVAL;
break;
}
optval = *mtod(m, int *);
if (optval < IPSEC_LEVEL_BYPASS ||
optval > IPSEC_LEVEL_UNIQUE) {
error = EINVAL;
break;
}
switch (optname) {
case IPV6_AUTH_LEVEL:
if (optval < IPSEC_AUTH_LEVEL_DEFAULT &&
suser(p)) {
error = EACCES;
break;
}
inp->inp_seclevel.sl_auth = optval;
break;
case IPV6_ESP_TRANS_LEVEL:
if (optval < IPSEC_ESP_TRANS_LEVEL_DEFAULT &&
suser(p)) {
error = EACCES;
break;
}
inp->inp_seclevel.sl_esp_trans = optval;
break;
case IPV6_ESP_NETWORK_LEVEL:
if (optval < IPSEC_ESP_NETWORK_LEVEL_DEFAULT &&
suser(p)) {
error = EACCES;
break;
}
inp->inp_seclevel.sl_esp_network = optval;
break;
case IPV6_IPCOMP_LEVEL:
if (optval < IPSEC_IPCOMP_LEVEL_DEFAULT &&
suser(p)) {
error = EACCES;
break;
}
inp->inp_seclevel.sl_ipcomp = optval;
break;
}
#endif
break;
case SO_RTABLE:
if (m == NULL || m->m_len < sizeof(u_int)) {
error = EINVAL;
break;
}
rtid = *mtod(m, u_int *);
if (inp->inp_rtableid == rtid)
break;
/* needs privileges to switch when already set */
if (rtableid != rtid && rtableid != 0 &&
(error = suser(p)) != 0)
break;
error = in_pcbset_rtableid(inp, rtid);
break;
case IPV6_PIPEX:
if (m != NULL && m->m_len == sizeof(int))
inp->inp_pipex = *mtod(m, int *);
else
error = EINVAL;
break;
default:
error = ENOPROTOOPT;
break;
}
break;
case PRCO_GETOPT:
switch (optname) {
case IPV6_RECVHOPOPTS:
case IPV6_RECVDSTOPTS:
case IPV6_UNICAST_HOPS:
case IPV6_MINHOPCOUNT:
case IPV6_RECVPKTINFO:
case IPV6_RECVHOPLIMIT:
case IPV6_RECVRTHDR:
case IPV6_RECVPATHMTU:
case IPV6_V6ONLY:
case IPV6_PORTRANGE:
case IPV6_RECVTCLASS:
case IPV6_AUTOFLOWLABEL:
case IPV6_RECVDSTPORT:
switch (optname) {
case IPV6_RECVHOPOPTS:
optval = OPTBIT(IN6P_HOPOPTS);
break;
case IPV6_RECVDSTOPTS:
optval = OPTBIT(IN6P_DSTOPTS);
break;
case IPV6_UNICAST_HOPS:
optval = inp->inp_hops;
break;
case IPV6_MINHOPCOUNT:
optval = inp->inp_ip6_minhlim;
break;
case IPV6_RECVPKTINFO:
optval = OPTBIT(IN6P_PKTINFO);
break;
case IPV6_RECVHOPLIMIT:
optval = OPTBIT(IN6P_HOPLIMIT);
break;
case IPV6_RECVRTHDR:
optval = OPTBIT(IN6P_RTHDR);
break;
case IPV6_RECVPATHMTU:
optval = OPTBIT(IN6P_MTU);
break;
case IPV6_V6ONLY:
optval = 1;
break;
case IPV6_PORTRANGE:
{
int flags;
flags = inp->inp_flags;
if (flags & IN6P_HIGHPORT)
optval = IPV6_PORTRANGE_HIGH;
else if (flags & IN6P_LOWPORT)
optval = IPV6_PORTRANGE_LOW;
else
optval = 0;
break;
}
case IPV6_RECVTCLASS:
optval = OPTBIT(IN6P_TCLASS);
break;
case IPV6_AUTOFLOWLABEL:
optval = OPTBIT(IN6P_AUTOFLOWLABEL);
break;
case IPV6_RECVDSTPORT:
optval = OPTBIT(IN6P_RECVDSTPORT);
break;
}
if (error)
break;
m->m_len = sizeof(int);
*mtod(m, int *) = optval;
break;
case IPV6_PATHMTU:
{
u_long pmtu = 0;
struct ip6_mtuinfo mtuinfo;
struct ifnet *ifp;
struct rtentry *rt;
if (!(so->so_state & SS_ISCONNECTED))
return (ENOTCONN);
rt = in6_pcbrtentry(inp);
if (!rtisvalid(rt))
return (EHOSTUNREACH);
ifp = if_get(rt->rt_ifidx);
if (ifp == NULL)
return (EHOSTUNREACH);
/*
* XXX: we dot not consider the case of source
* routing, or optional information to specify
* the outgoing interface.
*/
error = ip6_getpmtu(rt, ifp, &pmtu);
if_put(ifp);
if (error)
break;
if (pmtu > IPV6_MAXPACKET)
pmtu = IPV6_MAXPACKET;
bzero(&mtuinfo, sizeof(mtuinfo));
mtuinfo.ip6m_mtu = (u_int32_t)pmtu;
optdata = (void *)&mtuinfo;
optdatalen = sizeof(mtuinfo);
if (optdatalen > MCLBYTES)
return (EMSGSIZE); /* XXX */
if (optdatalen > MLEN)
MCLGET(m, M_WAIT);
m->m_len = optdatalen;
bcopy(optdata, mtod(m, void *), optdatalen);
break;
}
case IPV6_PKTINFO:
case IPV6_HOPOPTS:
case IPV6_RTHDR:
case IPV6_DSTOPTS:
case IPV6_RTHDRDSTOPTS:
case IPV6_TCLASS:
case IPV6_DONTFRAG:
case IPV6_USE_MIN_MTU:
error = ip6_getpcbopt(inp->inp_outputopts6,
optname, m);
break;
case IPV6_MULTICAST_IF:
case IPV6_MULTICAST_HOPS:
case IPV6_MULTICAST_LOOP:
case IPV6_JOIN_GROUP:
case IPV6_LEAVE_GROUP:
error = ip6_getmoptions(optname,
inp->inp_moptions6, m);
break;
case IPSEC6_OUTSA:
error = EINVAL;
break;
case IPV6_AUTH_LEVEL:
case IPV6_ESP_TRANS_LEVEL:
case IPV6_ESP_NETWORK_LEVEL:
case IPV6_IPCOMP_LEVEL:
#ifndef IPSEC
m->m_len = sizeof(int);
*mtod(m, int *) = IPSEC_LEVEL_NONE;
#else
m->m_len = sizeof(int);
switch (optname) {
case IPV6_AUTH_LEVEL:
optval = inp->inp_seclevel.sl_auth;
break;
case IPV6_ESP_TRANS_LEVEL:
optval =
inp->inp_seclevel.sl_esp_trans;
break;
case IPV6_ESP_NETWORK_LEVEL:
optval =
inp->inp_seclevel.sl_esp_network;
break;
case IPV6_IPCOMP_LEVEL:
optval = inp->inp_seclevel.sl_ipcomp;
break;
}
*mtod(m, int *) = optval;
#endif
break;
case SO_RTABLE:
m->m_len = sizeof(u_int);
*mtod(m, u_int *) = inp->inp_rtableid;
break;
case IPV6_PIPEX:
m->m_len = sizeof(int);
*mtod(m, int *) = inp->inp_pipex;
break;
default:
error = ENOPROTOOPT;
break;
}
break;
}
return (error);
}
int
ip6_raw_ctloutput(int op, struct socket *so, int level, int optname,
struct mbuf *m)
{
int error = 0, optval;
const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
struct inpcb *inp = sotoinpcb(so);
if (level != IPPROTO_IPV6)
return (EINVAL);
switch (optname) {
case IPV6_CHECKSUM:
/*
* For ICMPv6 sockets, no modification allowed for checksum
* offset, permit "no change" values to help existing apps.
*
* RFC3542 says: "An attempt to set IPV6_CHECKSUM
* for an ICMPv6 socket will fail."
* The current behavior does not meet RFC3542.
*/
switch (op) {
case PRCO_SETOPT:
if (m == NULL || m->m_len != sizeof(int)) {
error = EINVAL;
break;
}
optval = *mtod(m, int *);
if (optval < -1 ||
(optval > 0 && (optval % 2) != 0)) {
/*
* The API assumes non-negative even offset
* values or -1 as a special value.
*/
error = EINVAL;
} else if (so->so_proto->pr_protocol ==
IPPROTO_ICMPV6) {
if (optval != icmp6off)
error = EINVAL;
} else
inp->inp_cksum6 = optval;
break;
case PRCO_GETOPT:
if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
optval = icmp6off;
else
optval = inp->inp_cksum6;
m->m_len = sizeof(int);
*mtod(m, int *) = optval;
break;
default:
error = EINVAL;
break;
}
break;
default:
error = ENOPROTOOPT;
break;
}
return (error);
}
/*
* initialize ip6_pktopts. beware that there are non-zero default values in
* the struct.
*/
void
ip6_initpktopts(struct ip6_pktopts *opt)
{
bzero(opt, sizeof(*opt));
opt->ip6po_hlim = -1; /* -1 means default hop limit */
opt->ip6po_tclass = -1; /* -1 means default traffic class */
opt->ip6po_minmtu = IP6PO_MINMTU_MCASTONLY;
}
int
ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
int priv, int uproto)
{
struct ip6_pktopts *opt;
if (*pktopt == NULL) {
*pktopt = malloc(sizeof(struct ip6_pktopts), M_IP6OPT,
M_WAITOK);
ip6_initpktopts(*pktopt);
}
opt = *pktopt;
return (ip6_setpktopt(optname, buf, len, opt, priv, 1, uproto));
}
int
ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct mbuf *m)
{
void *optdata = NULL;
int optdatalen = 0;
struct ip6_ext *ip6e;
int error = 0;
struct in6_pktinfo null_pktinfo;
int deftclass = 0, on;
int defminmtu = IP6PO_MINMTU_MCASTONLY;
switch (optname) {
case IPV6_PKTINFO:
if (pktopt && pktopt->ip6po_pktinfo)
optdata = (void *)pktopt->ip6po_pktinfo;
else {
/* XXX: we don't have to do this every time... */
bzero(&null_pktinfo, sizeof(null_pktinfo));
optdata = (void *)&null_pktinfo;
}
optdatalen = sizeof(struct in6_pktinfo);
break;
case IPV6_TCLASS:
if (pktopt && pktopt->ip6po_tclass >= 0)
optdata = (void *)&pktopt->ip6po_tclass;
else
optdata = (void *)&deftclass;
optdatalen = sizeof(int);
break;
case IPV6_HOPOPTS:
if (pktopt && pktopt->ip6po_hbh) {
optdata = (void *)pktopt->ip6po_hbh;
ip6e = (struct ip6_ext *)pktopt->ip6po_hbh;
optdatalen = (ip6e->ip6e_len + 1) << 3;
}
break;
case IPV6_RTHDR:
if (pktopt && pktopt->ip6po_rthdr) {
optdata = (void *)pktopt->ip6po_rthdr;
ip6e = (struct ip6_ext *)pktopt->ip6po_rthdr;
optdatalen = (ip6e->ip6e_len + 1) << 3;
}
break;
case IPV6_RTHDRDSTOPTS:
if (pktopt && pktopt->ip6po_dest1) {
optdata = (void *)pktopt->ip6po_dest1;
ip6e = (struct ip6_ext *)pktopt->ip6po_dest1;
optdatalen = (ip6e->ip6e_len + 1) << 3;
}
break;
case IPV6_DSTOPTS:
if (pktopt && pktopt->ip6po_dest2) {
optdata = (void *)pktopt->ip6po_dest2;
ip6e = (struct ip6_ext *)pktopt->ip6po_dest2;
optdatalen = (ip6e->ip6e_len + 1) << 3;
}
break;
case IPV6_USE_MIN_MTU:
if (pktopt)
optdata = (void *)&pktopt->ip6po_minmtu;
else
optdata = (void *)&defminmtu;
optdatalen = sizeof(int);
break;
case IPV6_DONTFRAG:
if (pktopt && ((pktopt->ip6po_flags) & IP6PO_DONTFRAG))
on = 1;
else
on = 0;
optdata = (void *)&on;
optdatalen = sizeof(on);
break;
default: /* should not happen */
#ifdef DIAGNOSTIC
panic("%s: unexpected option", __func__);
#endif
return (ENOPROTOOPT);
}
if (optdatalen > MCLBYTES)
return (EMSGSIZE); /* XXX */
if (optdatalen > MLEN)
MCLGET(m, M_WAIT);
m->m_len = optdatalen;
if (optdatalen)
bcopy(optdata, mtod(m, void *), optdatalen);
return (error);
}
void
ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
{
if (optname == -1 || optname == IPV6_PKTINFO) {
if (pktopt->ip6po_pktinfo)
free(pktopt->ip6po_pktinfo, M_IP6OPT, 0);
pktopt->ip6po_pktinfo = NULL;
}
if (optname == -1 || optname == IPV6_HOPLIMIT)
pktopt->ip6po_hlim = -1;
if (optname == -1 || optname == IPV6_TCLASS)
pktopt->ip6po_tclass = -1;
if (optname == -1 || optname == IPV6_HOPOPTS) {
if (pktopt->ip6po_hbh)
free(pktopt->ip6po_hbh, M_IP6OPT, 0);
pktopt->ip6po_hbh = NULL;
}
if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
if (pktopt->ip6po_dest1)
free(pktopt->ip6po_dest1, M_IP6OPT, 0);
pktopt->ip6po_dest1 = NULL;
}
if (optname == -1 || optname == IPV6_RTHDR) {
if (pktopt->ip6po_rhinfo.ip6po_rhi_rthdr)
free(pktopt->ip6po_rhinfo.ip6po_rhi_rthdr, M_IP6OPT, 0);
pktopt->ip6po_rhinfo.ip6po_rhi_rthdr = NULL;
if (pktopt->ip6po_route.ro_rt) {
rtfree(pktopt->ip6po_route.ro_rt);
pktopt->ip6po_route.ro_rt = NULL;
}
}
if (optname == -1 || optname == IPV6_DSTOPTS) {
if (pktopt->ip6po_dest2)
free(pktopt->ip6po_dest2, M_IP6OPT, 0);
pktopt->ip6po_dest2 = NULL;
}
}
#define PKTOPT_EXTHDRCPY(type) \
do {\
if (src->type) {\
size_t hlen;\
hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
dst->type = malloc(hlen, M_IP6OPT, M_NOWAIT);\
if (dst->type == NULL)\
goto bad;\
memcpy(dst->type, src->type, hlen);\
}\
} while (/*CONSTCOND*/ 0)
int
copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src)
{
dst->ip6po_hlim = src->ip6po_hlim;
dst->ip6po_tclass = src->ip6po_tclass;
dst->ip6po_flags = src->ip6po_flags;
if (src->ip6po_pktinfo) {
dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
M_IP6OPT, M_NOWAIT);
if (dst->ip6po_pktinfo == NULL)
goto bad;
*dst->ip6po_pktinfo = *src->ip6po_pktinfo;
}
PKTOPT_EXTHDRCPY(ip6po_hbh);
PKTOPT_EXTHDRCPY(ip6po_dest1);
PKTOPT_EXTHDRCPY(ip6po_dest2);
PKTOPT_EXTHDRCPY(ip6po_rthdr); /* not copy the cached route */
return (0);
bad:
ip6_clearpktopts(dst, -1);
return (ENOBUFS);
}
#undef PKTOPT_EXTHDRCPY
void
ip6_freepcbopts(struct ip6_pktopts *pktopt)
{
if (pktopt == NULL)
return;
ip6_clearpktopts(pktopt, -1);
free(pktopt, M_IP6OPT, 0);
}
/*
* Set the IP6 multicast options in response to user setsockopt().
*/
int
ip6_setmoptions(int optname, struct ip6_moptions **im6op, struct mbuf *m,
unsigned int rtableid)
{
int error = 0;
u_int loop, ifindex;
struct ipv6_mreq *mreq;
struct ifnet *ifp;
struct ip6_moptions *im6o = *im6op;
struct in6_multi_mship *imm;
struct proc *p = curproc; /* XXX */
if (im6o == NULL) {
/*
* No multicast option buffer attached to the pcb;
* allocate one and initialize to default values.
*/
im6o = malloc(sizeof(*im6o), M_IPMOPTS, M_WAITOK);
if (im6o == NULL)
return (ENOBUFS);
*im6op = im6o;
im6o->im6o_ifidx = 0;
im6o->im6o_hlim = ip6_defmcasthlim;
im6o->im6o_loop = IPV6_DEFAULT_MULTICAST_LOOP;
LIST_INIT(&im6o->im6o_memberships);
}
switch (optname) {
case IPV6_MULTICAST_IF:
/*
* Select the interface for outgoing multicast packets.
*/
if (m == NULL || m->m_len != sizeof(u_int)) {
error = EINVAL;
break;
}
memcpy(&ifindex, mtod(m, u_int *), sizeof(ifindex));
if (ifindex != 0) {
ifp = if_get(ifindex);
if (ifp == NULL) {
error = ENXIO; /* XXX EINVAL? */
break;
}
if (ifp->if_rdomain != rtable_l2(rtableid) ||
(ifp->if_flags & IFF_MULTICAST) == 0) {
error = EADDRNOTAVAIL;
if_put(ifp);
break;
}
if_put(ifp);
}
im6o->im6o_ifidx = ifindex;
break;
case IPV6_MULTICAST_HOPS:
{
/*
* Set the IP6 hoplimit for outgoing multicast packets.
*/
int optval;
if (m == NULL || m->m_len != sizeof(int)) {
error = EINVAL;
break;
}
memcpy(&optval, mtod(m, u_int *), sizeof(optval));
if (optval < -1 || optval >= 256)
error = EINVAL;
else if (optval == -1)
im6o->im6o_hlim = ip6_defmcasthlim;
else
im6o->im6o_hlim = optval;
break;
}
case IPV6_MULTICAST_LOOP:
/*
* Set the loopback flag for outgoing multicast packets.
* Must be zero or one.
*/
if (m == NULL || m->m_len != sizeof(u_int)) {
error = EINVAL;
break;
}
memcpy(&loop, mtod(m, u_int *), sizeof(loop));
if (loop > 1) {
error = EINVAL;
break;
}
im6o->im6o_loop = loop;
break;
case IPV6_JOIN_GROUP:
/*
* Add a multicast group membership.
* Group must be a valid IP6 multicast address.
*/
if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
error = EINVAL;
break;
}
mreq = mtod(m, struct ipv6_mreq *);
if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
/*
* We use the unspecified address to specify to accept
* all multicast addresses. Only super user is allowed
* to do this.
*/
if (suser(p))
{
error = EACCES;
break;
}
} else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
error = EINVAL;
break;
}
/*
* If no interface was explicitly specified, choose an
* appropriate one according to the given multicast address.
*/
if (mreq->ipv6mr_interface == 0) {
struct rtentry *rt;
struct sockaddr_in6 dst;
memset(&dst, 0, sizeof(dst));
dst.sin6_len = sizeof(dst);
dst.sin6_family = AF_INET6;
dst.sin6_addr = mreq->ipv6mr_multiaddr;
rt = rtalloc(sin6tosa(&dst), RT_RESOLVE, rtableid);
if (rt == NULL) {
error = EADDRNOTAVAIL;
break;
}
ifp = if_get(rt->rt_ifidx);
rtfree(rt);
} else {
/*
* If the interface is specified, validate it.
*/
ifp = if_get(mreq->ipv6mr_interface);
if (ifp == NULL) {
error = ENXIO; /* XXX EINVAL? */
break;
}
}
/*
* See if we found an interface, and confirm that it
* supports multicast
*/
if (ifp == NULL || ifp->if_rdomain != rtable_l2(rtableid) ||
(ifp->if_flags & IFF_MULTICAST) == 0) {
if_put(ifp);
error = EADDRNOTAVAIL;
break;
}
/*
* Put interface index into the multicast address,
* if the address has link/interface-local scope.
*/
if (IN6_IS_SCOPE_EMBED(&mreq->ipv6mr_multiaddr)) {
mreq->ipv6mr_multiaddr.s6_addr16[1] =
htons(ifp->if_index);
}
/*
* See if the membership already exists.
*/
LIST_FOREACH(imm, &im6o->im6o_memberships, i6mm_chain)
if (imm->i6mm_maddr->in6m_ifidx == ifp->if_index &&
IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
&mreq->ipv6mr_multiaddr))
break;
if (imm != NULL) {
if_put(ifp);
error = EADDRINUSE;
break;
}
/*
* Everything looks good; add a new record to the multicast
* address list for the given interface.
*/
imm = in6_joingroup(ifp, &mreq->ipv6mr_multiaddr, &error);
if_put(ifp);
if (!imm)
break;
LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain);
break;
case IPV6_LEAVE_GROUP:
/*
* Drop a multicast group membership.
* Group must be a valid IP6 multicast address.
*/
if (m == NULL || m->m_len != sizeof(struct ipv6_mreq)) {
error = EINVAL;
break;
}
mreq = mtod(m, struct ipv6_mreq *);
if (IN6_IS_ADDR_UNSPECIFIED(&mreq->ipv6mr_multiaddr)) {
if (suser(p)) {
error = EACCES;
break;
}
} else if (!IN6_IS_ADDR_MULTICAST(&mreq->ipv6mr_multiaddr)) {
error = EINVAL;
break;
}
/*
* Put interface index into the multicast address,
* if the address has link-local scope.
*/
if (IN6_IS_ADDR_MC_LINKLOCAL(&mreq->ipv6mr_multiaddr)) {
mreq->ipv6mr_multiaddr.s6_addr16[1] =
htons(mreq->ipv6mr_interface);
}
/*
* If an interface address was specified, get a pointer
* to its ifnet structure.
*/
if (mreq->ipv6mr_interface == 0)
ifp = NULL;
else {
ifp = if_get(mreq->ipv6mr_interface);
if (ifp == NULL) {
error = ENXIO; /* XXX EINVAL? */
break;
}
}
/*
* Find the membership in the membership list.
*/
LIST_FOREACH(imm, &im6o->im6o_memberships, i6mm_chain) {
if ((ifp == NULL ||
imm->i6mm_maddr->in6m_ifidx == ifp->if_index) &&
IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
&mreq->ipv6mr_multiaddr))
break;
}
if_put(ifp);
if (imm == NULL) {
/* Unable to resolve interface */
error = EADDRNOTAVAIL;
break;
}
/*
* Give up the multicast address record to which the
* membership points.
*/
LIST_REMOVE(imm, i6mm_chain);
in6_leavegroup(imm);
break;
default:
error = EOPNOTSUPP;
break;
}
/*
* If all options have default values, no need to keep the option
* structure.
*/
if (im6o->im6o_ifidx == 0 &&
im6o->im6o_hlim == ip6_defmcasthlim &&
im6o->im6o_loop == IPV6_DEFAULT_MULTICAST_LOOP &&
LIST_EMPTY(&im6o->im6o_memberships)) {
free(*im6op, M_IPMOPTS, sizeof(**im6op));
*im6op = NULL;
}
return (error);
}
/*
* Return the IP6 multicast options in response to user getsockopt().
*/
int
ip6_getmoptions(int optname, struct ip6_moptions *im6o, struct mbuf *m)
{
u_int *hlim, *loop, *ifindex;
switch (optname) {
case IPV6_MULTICAST_IF:
ifindex = mtod(m, u_int *);
m->m_len = sizeof(u_int);
if (im6o == NULL || im6o->im6o_ifidx == 0)
*ifindex = 0;
else
*ifindex = im6o->im6o_ifidx;
return (0);
case IPV6_MULTICAST_HOPS:
hlim = mtod(m, u_int *);
m->m_len = sizeof(u_int);
if (im6o == NULL)
*hlim = ip6_defmcasthlim;
else
*hlim = im6o->im6o_hlim;
return (0);
case IPV6_MULTICAST_LOOP:
loop = mtod(m, u_int *);
m->m_len = sizeof(u_int);
if (im6o == NULL)
*loop = ip6_defmcasthlim;
else
*loop = im6o->im6o_loop;
return (0);
default:
return (EOPNOTSUPP);
}
}
/*
* Discard the IP6 multicast options.
*/
void
ip6_freemoptions(struct ip6_moptions *im6o)
{
struct in6_multi_mship *imm;
if (im6o == NULL)
return;
while (!LIST_EMPTY(&im6o->im6o_memberships)) {
imm = LIST_FIRST(&im6o->im6o_memberships);
LIST_REMOVE(imm, i6mm_chain);
in6_leavegroup(imm);
}
free(im6o, M_IPMOPTS, sizeof(*im6o));
}
/*
* Set IPv6 outgoing packet options based on advanced API.
*/
int
ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
struct ip6_pktopts *stickyopt, int priv, int uproto)
{
u_int clen;
struct cmsghdr *cm = 0;
caddr_t cmsgs;
int error;
if (control == NULL || opt == NULL)
return (EINVAL);
ip6_initpktopts(opt);
if (stickyopt) {
int error;
/*
* If stickyopt is provided, make a local copy of the options
* for this particular packet, then override them by ancillary
* objects.
* XXX: copypktopts() does not copy the cached route to a next
* hop (if any). This is not very good in terms of efficiency,
* but we can allow this since this option should be rarely
* used.
*/
if ((error = copypktopts(opt, stickyopt)) != 0)
return (error);
}
/*
* XXX: Currently, we assume all the optional information is stored
* in a single mbuf.
*/
if (control->m_next)
return (EINVAL);
clen = control->m_len;
cmsgs = mtod(control, caddr_t);
do {
if (clen < CMSG_LEN(0))
return (EINVAL);
cm = (struct cmsghdr *)cmsgs;
if (cm->cmsg_len < CMSG_LEN(0) || cm->cmsg_len > clen ||
CMSG_ALIGN(cm->cmsg_len) > clen)
return (EINVAL);
if (cm->cmsg_level == IPPROTO_IPV6) {
error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
cm->cmsg_len - CMSG_LEN(0), opt, priv, 0, uproto);
if (error)
return (error);
}
clen -= CMSG_ALIGN(cm->cmsg_len);
cmsgs += CMSG_ALIGN(cm->cmsg_len);
} while (clen);
return (0);
}
/*
* Set a particular packet option, as a sticky option or an ancillary data
* item. "len" can be 0 only when it's a sticky option.
*/
int
ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
int priv, int sticky, int uproto)
{
int minmtupolicy;
switch (optname) {
case IPV6_PKTINFO:
{
struct ifnet *ifp = NULL;
struct in6_pktinfo *pktinfo;
if (len != sizeof(struct in6_pktinfo))
return (EINVAL);
pktinfo = (struct in6_pktinfo *)buf;
/*
* An application can clear any sticky IPV6_PKTINFO option by
* doing a "regular" setsockopt with ipi6_addr being
* in6addr_any and ipi6_ifindex being zero.
* [RFC 3542, Section 6]
*/
if (opt->ip6po_pktinfo &&
pktinfo->ipi6_ifindex == 0 &&
IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
ip6_clearpktopts(opt, optname);
break;
}
if (uproto == IPPROTO_TCP &&
sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
return (EINVAL);
}
if (pktinfo->ipi6_ifindex) {
ifp = if_get(pktinfo->ipi6_ifindex);
if (ifp == NULL)
return (ENXIO);
if_put(ifp);
}
/*
* We store the address anyway, and let in6_selectsrc()
* validate the specified address. This is because ipi6_addr
* may not have enough information about its scope zone, and
* we may need additional information (such as outgoing
* interface or the scope zone of a destination address) to
* disambiguate the scope.
* XXX: the delay of the validation may confuse the
* application when it is used as a sticky option.
*/
if (opt->ip6po_pktinfo == NULL) {
opt->ip6po_pktinfo = malloc(sizeof(*pktinfo),
M_IP6OPT, M_NOWAIT);
if (opt->ip6po_pktinfo == NULL)
return (ENOBUFS);
}
bcopy(pktinfo, opt->ip6po_pktinfo, sizeof(*pktinfo));
break;
}
case IPV6_HOPLIMIT:
{
int *hlimp;
/*
* RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
* to simplify the ordering among hoplimit options.
*/
if (sticky)
return (ENOPROTOOPT);
if (len != sizeof(int))
return (EINVAL);
hlimp = (int *)buf;
if (*hlimp < -1 || *hlimp > 255)
return (EINVAL);
opt->ip6po_hlim = *hlimp;
break;
}
case IPV6_TCLASS:
{
int tclass;
if (len != sizeof(int))
return (EINVAL);
tclass = *(int *)buf;
if (tclass < -1 || tclass > 255)
return (EINVAL);
opt->ip6po_tclass = tclass;
break;
}
case IPV6_HOPOPTS:
{
struct ip6_hbh *hbh;
int hbhlen;
/*
* XXX: We don't allow a non-privileged user to set ANY HbH
* options, since per-option restriction has too much
* overhead.
*/
if (!priv)
return (EPERM);
if (len == 0) {
ip6_clearpktopts(opt, IPV6_HOPOPTS);
break; /* just remove the option */
}
/* message length validation */
if (len < sizeof(struct ip6_hbh))
return (EINVAL);
hbh = (struct ip6_hbh *)buf;
hbhlen = (hbh->ip6h_len + 1) << 3;
if (len != hbhlen)
return (EINVAL);
/* turn off the previous option, then set the new option. */
ip6_clearpktopts(opt, IPV6_HOPOPTS);
opt->ip6po_hbh = malloc(hbhlen, M_IP6OPT, M_NOWAIT);
if (opt->ip6po_hbh == NULL)
return (ENOBUFS);
memcpy(opt->ip6po_hbh, hbh, hbhlen);
break;
}
case IPV6_DSTOPTS:
case IPV6_RTHDRDSTOPTS:
{
struct ip6_dest *dest, **newdest = NULL;
int destlen;
if (!priv) /* XXX: see the comment for IPV6_HOPOPTS */
return (EPERM);
if (len == 0) {
ip6_clearpktopts(opt, optname);
break; /* just remove the option */
}
/* message length validation */
if (len < sizeof(struct ip6_dest))
return (EINVAL);
dest = (struct ip6_dest *)buf;
destlen = (dest->ip6d_len + 1) << 3;
if (len != destlen)
return (EINVAL);
/*
* Determine the position that the destination options header
* should be inserted; before or after the routing header.
*/
switch (optname) {
case IPV6_RTHDRDSTOPTS:
newdest = &opt->ip6po_dest1;
break;
case IPV6_DSTOPTS:
newdest = &opt->ip6po_dest2;
break;
}
/* turn off the previous option, then set the new option. */
ip6_clearpktopts(opt, optname);
*newdest = malloc(destlen, M_IP6OPT, M_NOWAIT);
if (*newdest == NULL)
return (ENOBUFS);
memcpy(*newdest, dest, destlen);
break;
}
case IPV6_RTHDR:
{
struct ip6_rthdr *rth;
int rthlen;
if (len == 0) {
ip6_clearpktopts(opt, IPV6_RTHDR);
break; /* just remove the option */
}
/* message length validation */
if (len < sizeof(struct ip6_rthdr))
return (EINVAL);
rth = (struct ip6_rthdr *)buf;
rthlen = (rth->ip6r_len + 1) << 3;
if (len != rthlen)
return (EINVAL);
switch (rth->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
if (rth->ip6r_len == 0) /* must contain one addr */
return (EINVAL);
if (rth->ip6r_len % 2) /* length must be even */
return (EINVAL);
if (rth->ip6r_len / 2 != rth->ip6r_segleft)
return (EINVAL);
break;
default:
return (EINVAL); /* not supported */
}
/* turn off the previous option */
ip6_clearpktopts(opt, IPV6_RTHDR);
opt->ip6po_rthdr = malloc(rthlen, M_IP6OPT, M_NOWAIT);
if (opt->ip6po_rthdr == NULL)
return (ENOBUFS);
memcpy(opt->ip6po_rthdr, rth, rthlen);
break;
}
case IPV6_USE_MIN_MTU:
if (len != sizeof(int))
return (EINVAL);
minmtupolicy = *(int *)buf;
if (minmtupolicy != IP6PO_MINMTU_MCASTONLY &&
minmtupolicy != IP6PO_MINMTU_DISABLE &&
minmtupolicy != IP6PO_MINMTU_ALL) {
return (EINVAL);
}
opt->ip6po_minmtu = minmtupolicy;
break;
case IPV6_DONTFRAG:
if (len != sizeof(int))
return (EINVAL);
if (uproto == IPPROTO_TCP || *(int *)buf == 0) {
/*
* we ignore this option for TCP sockets.
* (RFC3542 leaves this case unspecified.)
*/
opt->ip6po_flags &= ~IP6PO_DONTFRAG;
} else
opt->ip6po_flags |= IP6PO_DONTFRAG;
break;
default:
return (ENOPROTOOPT);
} /* end of switch */
return (0);
}
/*
* Routine called from ip6_output() to loop back a copy of an IP6 multicast
* packet to the input queue of a specified interface.
*/
void
ip6_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in6 *dst)
{
struct mbuf *copym;
struct ip6_hdr *ip6;
/*
* Duplicate the packet.
*/
copym = m_copym(m, 0, M_COPYALL, M_NOWAIT);
if (copym == NULL)
return;
/*
* Make sure to deep-copy IPv6 header portion in case the data
* is in an mbuf cluster, so that we can safely override the IPv6
* header portion later.
*/
if ((copym->m_flags & M_EXT) != 0 ||
copym->m_len < sizeof(struct ip6_hdr)) {
copym = m_pullup(copym, sizeof(struct ip6_hdr));
if (copym == NULL)
return;
}
#ifdef DIAGNOSTIC
if (copym->m_len < sizeof(*ip6)) {
m_freem(copym);
return;
}
#endif
ip6 = mtod(copym, struct ip6_hdr *);
if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src))
ip6->ip6_src.s6_addr16[1] = 0;
if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst))
ip6->ip6_dst.s6_addr16[1] = 0;
if_input_local(ifp, copym, dst->sin6_family);
}
/*
* Chop IPv6 header off from the payload.
*/
int
ip6_splithdr(struct mbuf *m, struct ip6_exthdrs *exthdrs)
{
struct mbuf *mh;
struct ip6_hdr *ip6;
ip6 = mtod(m, struct ip6_hdr *);
if (m->m_len > sizeof(*ip6)) {
MGET(mh, M_DONTWAIT, MT_HEADER);
if (mh == NULL) {
m_freem(m);
return ENOBUFS;
}
M_MOVE_PKTHDR(mh, m);
m_align(mh, sizeof(*ip6));
m->m_len -= sizeof(*ip6);
m->m_data += sizeof(*ip6);
mh->m_next = m;
m = mh;
m->m_len = sizeof(*ip6);
bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(*ip6));
}
exthdrs->ip6e_ip6 = m;
return 0;
}
u_int32_t
ip6_randomid(void)
{
return idgen32(&ip6_id_ctx);
}
void
ip6_randomid_init(void)
{
idgen32_init(&ip6_id_ctx);
}
/*
* Compute significant parts of the IPv6 checksum pseudo-header
* for use in a delayed TCP/UDP checksum calculation.
*/
static __inline u_int16_t __attribute__((__unused__))
in6_cksum_phdr(const struct in6_addr *src, const struct in6_addr *dst,
u_int32_t len, u_int32_t nxt)
{
u_int32_t sum = 0;
const u_int16_t *w;
w = (const u_int16_t *) src;
sum += w[0];
if (!IN6_IS_SCOPE_EMBED(src))
sum += w[1];
sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5];
sum += w[6]; sum += w[7];
w = (const u_int16_t *) dst;
sum += w[0];
if (!IN6_IS_SCOPE_EMBED(dst))
sum += w[1];
sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5];
sum += w[6]; sum += w[7];
sum += (u_int16_t)(len >> 16) + (u_int16_t)(len /*& 0xffff*/);
sum += (u_int16_t)(nxt >> 16) + (u_int16_t)(nxt /*& 0xffff*/);
sum = (u_int16_t)(sum >> 16) + (u_int16_t)(sum /*& 0xffff*/);
if (sum > 0xffff)
sum -= 0xffff;
return (sum);
}
/*
* Process a delayed payload checksum calculation.
*/
void
in6_delayed_cksum(struct mbuf *m, u_int8_t nxt)
{
int nxtp, offset;
u_int16_t csum;
offset = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxtp);
if (offset <= 0 || nxtp != nxt)
/* If the desired next protocol isn't found, punt. */
return;
csum = (u_int16_t)(in6_cksum(m, 0, offset, m->m_pkthdr.len - offset));
switch (nxt) {
case IPPROTO_TCP:
offset += offsetof(struct tcphdr, th_sum);
break;
case IPPROTO_UDP:
offset += offsetof(struct udphdr, uh_sum);
if (csum == 0)
csum = 0xffff;
break;
case IPPROTO_ICMPV6:
offset += offsetof(struct icmp6_hdr, icmp6_cksum);
break;
}
if ((offset + sizeof(u_int16_t)) > m->m_len)
m_copyback(m, offset, sizeof(csum), &csum, M_NOWAIT);
else
*(u_int16_t *)(mtod(m, caddr_t) + offset) = csum;
}
void
in6_proto_cksum_out(struct mbuf *m, struct ifnet *ifp)
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
/* some hw and in6_delayed_cksum need the pseudo header cksum */
if (m->m_pkthdr.csum_flags &
(M_TCP_CSUM_OUT|M_UDP_CSUM_OUT|M_ICMP_CSUM_OUT)) {
int nxt, offset;
u_int16_t csum;
offset = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
if (ISSET(m->m_pkthdr.csum_flags, M_TCP_TSO) &&
in_ifcap_cksum(m, ifp, IFCAP_TSOv6)) {
csum = in6_cksum_phdr(&ip6->ip6_src, &ip6->ip6_dst,
htonl(0), htonl(nxt));
} else {
csum = in6_cksum_phdr(&ip6->ip6_src, &ip6->ip6_dst,
htonl(m->m_pkthdr.len - offset), htonl(nxt));
}
if (nxt == IPPROTO_TCP)
offset += offsetof(struct tcphdr, th_sum);
else if (nxt == IPPROTO_UDP)
offset += offsetof(struct udphdr, uh_sum);
else if (nxt == IPPROTO_ICMPV6)
offset += offsetof(struct icmp6_hdr, icmp6_cksum);
if ((offset + sizeof(u_int16_t)) > m->m_len)
m_copyback(m, offset, sizeof(csum), &csum, M_NOWAIT);
else
*(u_int16_t *)(mtod(m, caddr_t) + offset) = csum;
}
if (m->m_pkthdr.csum_flags & M_TCP_CSUM_OUT) {
if (!ifp || !(ifp->if_capabilities & IFCAP_CSUM_TCPv6) ||
ip6->ip6_nxt != IPPROTO_TCP ||
ifp->if_bridgeidx != 0) {
tcpstat_inc(tcps_outswcsum);
in6_delayed_cksum(m, IPPROTO_TCP);
m->m_pkthdr.csum_flags &= ~M_TCP_CSUM_OUT; /* Clear */
}
} else if (m->m_pkthdr.csum_flags & M_UDP_CSUM_OUT) {
if (!ifp || !(ifp->if_capabilities & IFCAP_CSUM_UDPv6) ||
ip6->ip6_nxt != IPPROTO_UDP ||
ifp->if_bridgeidx != 0) {
udpstat_inc(udps_outswcsum);
in6_delayed_cksum(m, IPPROTO_UDP);
m->m_pkthdr.csum_flags &= ~M_UDP_CSUM_OUT; /* Clear */
}
} else if (m->m_pkthdr.csum_flags & M_ICMP_CSUM_OUT) {
in6_delayed_cksum(m, IPPROTO_ICMPV6);
m->m_pkthdr.csum_flags &= ~M_ICMP_CSUM_OUT; /* Clear */
}
}
#ifdef IPSEC
int
ip6_output_ipsec_lookup(struct mbuf *m, const struct ipsec_level *seclevel,
struct tdb **tdbout)
{
struct tdb *tdb;
struct m_tag *mtag;
struct tdb_ident *tdbi;
int error;
/*
* Check if there was an outgoing SA bound to the flow
* from a transport protocol.
*/
/* Do we have any pending SAs to apply ? */
error = ipsp_spd_lookup(m, AF_INET6, sizeof(struct ip6_hdr),
IPSP_DIRECTION_OUT, NULL, seclevel, &tdb, NULL);
if (error || tdb == NULL) {
*tdbout = NULL;
return error;
}
/* Loop detection */
for (mtag = m_tag_first(m); mtag != NULL; mtag = m_tag_next(m, mtag)) {
if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE)
continue;
tdbi = (struct tdb_ident *)(mtag + 1);
if (tdbi->spi == tdb->tdb_spi &&
tdbi->proto == tdb->tdb_sproto &&
tdbi->rdomain == tdb->tdb_rdomain &&
!memcmp(&tdbi->dst, &tdb->tdb_dst,
sizeof(union sockaddr_union))) {
/* no IPsec needed */
tdb_unref(tdb);
*tdbout = NULL;
return 0;
}
}
*tdbout = tdb;
return 0;
}
int
ip6_output_ipsec_pmtu_update(struct tdb *tdb, struct route *ro,
struct in6_addr *dst, int ifidx, int rtableid, int transportmode)
{
struct rtentry *rt = NULL;
int rt_mtucloned = 0;
/* Find a host route to store the mtu in */
if (ro != NULL)
rt = ro->ro_rt;
/* but don't add a PMTU route for transport mode SAs */
if (transportmode)
rt = NULL;
else if (rt == NULL || (rt->rt_flags & RTF_HOST) == 0) {
struct sockaddr_in6 sin6;
int error;
memset(&sin6, 0, sizeof(sin6));
sin6.sin6_family = AF_INET6;
sin6.sin6_len = sizeof(sin6);
sin6.sin6_addr = *dst;
sin6.sin6_scope_id = in6_addr2scopeid(ifidx, dst);
error = in6_embedscope(dst, &sin6, NULL, NULL);
if (error) {
/* should be impossible */
return error;
}
rt = icmp6_mtudisc_clone(&sin6, rtableid, 1);
rt_mtucloned = 1;
}
DPRINTF("spi %08x mtu %d rt %p cloned %d",
ntohl(tdb->tdb_spi), tdb->tdb_mtu, rt, rt_mtucloned);
if (rt != NULL) {
rt->rt_mtu = tdb->tdb_mtu;
if (ro != NULL && ro->ro_rt != NULL) {
rtfree(ro->ro_rt);
ro->ro_rt = rtalloc(&ro->ro_dstsa, RT_RESOLVE,
rtableid);
}
if (rt_mtucloned)
rtfree(rt);
}
return 0;
}
int
ip6_output_ipsec_send(struct tdb *tdb, struct mbuf *m, struct route *ro,
int tunalready, int fwd)
{
struct mbuf_list ml;
struct ifnet *encif = NULL;
struct ip6_hdr *ip6;
struct in6_addr dst;
u_int len;
int error, ifidx, rtableid, tso = 0;
#if NPF > 0
/*
* Packet filter
*/
if ((encif = enc_getif(tdb->tdb_rdomain, tdb->tdb_tap)) == NULL ||
pf_test(AF_INET6, fwd ? PF_FWD : PF_OUT, encif, &m) != PF_PASS) {
m_freem(m);
return EACCES;
}
if (m == NULL)
return 0;
/*
* PF_TAG_REROUTE handling or not...
* Packet is entering IPsec so the routing is
* already overruled by the IPsec policy.
* Until now the change was not reconsidered.
* What's the behaviour?
*/
#endif
/* Check if we can chop the TCP packet */
ip6 = mtod(m, struct ip6_hdr *);
if (ISSET(m->m_pkthdr.csum_flags, M_TCP_TSO) &&
m->m_pkthdr.ph_mss <= tdb->tdb_mtu) {
tso = 1;
len = m->m_pkthdr.ph_mss;
} else
len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen);
/* Check if we are allowed to fragment */
dst = ip6->ip6_dst;
ifidx = m->m_pkthdr.ph_ifidx;
rtableid = m->m_pkthdr.ph_rtableid;
if (ip_mtudisc && tdb->tdb_mtu &&
len > tdb->tdb_mtu && tdb->tdb_mtutimeout > gettime()) {
int transportmode;
transportmode = (tdb->tdb_dst.sa.sa_family == AF_INET6) &&
(IN6_ARE_ADDR_EQUAL(&tdb->tdb_dst.sin6.sin6_addr, &dst));
error = ip6_output_ipsec_pmtu_update(tdb, ro, &dst, ifidx,
rtableid, transportmode);
if (error) {
ipsecstat_inc(ipsec_odrops);
tdbstat_inc(tdb, tdb_odrops);
m_freem(m);
return error;
}
ipsec_adjust_mtu(m, tdb->tdb_mtu);
m_freem(m);
return EMSGSIZE;
}
/* propagate don't fragment for v6-over-v6 */
if (ip_mtudisc)
SET(m->m_pkthdr.csum_flags, M_IPV6_DF_OUT);
/*
* Clear these -- they'll be set in the recursive invocation
* as needed.
*/
m->m_flags &= ~(M_BCAST | M_MCAST);
if (tso) {
error = tcp_chopper(m, &ml, encif, len);
if (error)
goto done;
} else {
CLR(m->m_pkthdr.csum_flags, M_TCP_TSO);
in6_proto_cksum_out(m, encif);
ml_init(&ml);
ml_enqueue(&ml, m);
}
KERNEL_LOCK();
while ((m = ml_dequeue(&ml)) != NULL) {
/* Callee frees mbuf */
error = ipsp_process_packet(m, tdb, AF_INET6, tunalready);
if (error)
break;
}
KERNEL_UNLOCK();
done:
if (error) {
ml_purge(&ml);
ipsecstat_inc(ipsec_odrops);
tdbstat_inc(tdb, tdb_odrops);
}
if (!error && tso)
tcpstat_inc(tcps_outswtso);
if (ip_mtudisc && error == EMSGSIZE)
ip6_output_ipsec_pmtu_update(tdb, ro, &dst, ifidx, rtableid, 0);
return error;
}
#endif /* IPSEC */
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