freebsd-dev/sys/netinet6/ip6_output.c
Alexander V. Chernikov 1fe201c322 Simplify the way of attaching IPv6 link-layer header.
Problem description:
How do we currently perform layer 2 resolution and header imposition:

For IPv4 we have the following chain:
  ip_output() -> (ether|atm|whatever)_output() -> arpresolve()

Lookup is done in proper place (link-layer output routine) and it is possible
  to provide cached lle data.

For IPv6 situation is more complex:
  ip6_output() -> nd6_output() -> nd6_output_ifp() -> (whatever)_output() ->
    nd6_storelladdr()

We have ip6_ouput() which calls nd6_output() instead of link output routine.
nd6_output() does the following:
  * checks if lle exists, creates it if needed (similar to arpresolve())
  * performes lle state transitions (similar to arpresolve())
  * calls nd6_output_ifp() which pushes packets to link output routine along
    with running SeND/MAC hooks regardless of lle state
    (e.g. works as run-hooks placeholder).

After that, iface output routine like ether_output() calls nd6_storelladdr()
  which performs lle lookup once again.

As a result, we perform lookup twice for each outgoing packet for most types
  of interfaces. We also need to maintain runtime-checked table of 'nd6-free'
  interfaces (see nd6_need_cache()).

Fix this behavior by eliminating first ND lookup. To be more specific:
  * make all nd6_output() consumers use nd6_output_ifp() instead
  * rename nd6_output[_slow]() to nd6_resolve_[slow]()
  * convert nd6_resolve() and nd6_resolve_slow() to arpresolve() semantics,
    e.g. copy L2 address to buffer instead of pushing packet towards lower
    layers
  * Make all nd6_storelladdr() users use nd6_resolve()
  * eliminate nd6_storelladdr()

The resulting callchain is the following:
  ip6_output() -> nd6_output_ifp() -> (whatever)_output() -> nd6_resolve()

Error handling:
Currently sending packet to non-existing la results in ip6_<output|forward>
  -> nd6_output() -> nd6_output _lle() which returns 0.
In new scenario packet is propagated to <ether|whatever>_output() ->
  nd6_resolve() which will return EWOULDBLOCK, and that result
  will be converted to 0.

(And EWOULDBLOCK is actually used by IB/TOE code).

Sponsored by:		Yandex LLC
Differential Revision:	https://reviews.freebsd.org/D1469
2015-09-16 14:26:28 +00:00

2998 lines
75 KiB
C

/*-
* 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.
*
* $KAME: ip6_output.c,v 1.279 2002/01/26 06:12:30 jinmei Exp $
*/
/*-
* 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)ip_output.c 8.3 (Berkeley) 1/21/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipfw.h"
#include "opt_ipsec.h"
#include "opt_sctp.h"
#include "opt_route.h"
#include "opt_rss.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/errno.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/syslog.h>
#include <sys/ucred.h>
#include <machine/in_cksum.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/netisr.h>
#include <net/route.h>
#include <net/pfil.h>
#include <net/rss_config.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/ip_var.h>
#include <netinet6/in6_var.h>
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include <netinet6/ip6_var.h>
#include <netinet/in_pcb.h>
#include <netinet/tcp_var.h>
#include <netinet6/nd6.h>
#include <netinet6/in6_rss.h>
#ifdef IPSEC
#include <netipsec/ipsec.h>
#include <netipsec/ipsec6.h>
#include <netipsec/key.h>
#include <netinet6/ip6_ipsec.h>
#endif /* IPSEC */
#ifdef SCTP
#include <netinet/sctp.h>
#include <netinet/sctp_crc32.h>
#endif
#include <netinet6/ip6protosw.h>
#include <netinet6/scope6_var.h>
#ifdef FLOWTABLE
#include <net/flowtable.h>
#endif
extern int in6_mcast_loop;
struct ip6_exthdrs {
struct mbuf *ip6e_ip6;
struct mbuf *ip6e_hbh;
struct mbuf *ip6e_dest1;
struct mbuf *ip6e_rthdr;
struct mbuf *ip6e_dest2;
};
static int ip6_pcbopt(int, u_char *, int, struct ip6_pktopts **,
struct ucred *, int);
static int ip6_pcbopts(struct ip6_pktopts **, struct mbuf *,
struct socket *, struct sockopt *);
static int ip6_getpcbopt(struct ip6_pktopts *, int, struct sockopt *);
static int ip6_setpktopt(int, u_char *, int, struct ip6_pktopts *,
struct ucred *, int, int, int);
static int ip6_copyexthdr(struct mbuf **, caddr_t, int);
static int ip6_insertfraghdr(struct mbuf *, struct mbuf *, int,
struct ip6_frag **);
static int ip6_insert_jumboopt(struct ip6_exthdrs *, u_int32_t);
static int ip6_splithdr(struct mbuf *, struct ip6_exthdrs *);
static int ip6_getpmtu(struct route_in6 *, struct route_in6 *,
struct ifnet *, struct in6_addr *, u_long *, int *, u_int);
static int copypktopts(struct ip6_pktopts *, struct ip6_pktopts *, int);
/*
* Make an extension header from option data. hp is the source, and
* mp is the destination.
*/
#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 (/*CONSTCOND*/ 0)
/*
* Form a chain of extension headers.
* m is the extension header mbuf
* mp is the previous mbuf in the chain
* p is the next header
* i is the type of option.
*/
#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 (/*CONSTCOND*/ 0)
void
in6_delayed_cksum(struct mbuf *m, uint32_t plen, u_short offset)
{
u_short csum;
csum = in_cksum_skip(m, offset + plen, offset);
if (m->m_pkthdr.csum_flags & CSUM_UDP_IPV6 && csum == 0)
csum = 0xffff;
offset += m->m_pkthdr.csum_data; /* checksum offset */
if (offset + sizeof(u_short) > m->m_len) {
printf("%s: delayed m_pullup, m->len: %d plen %u off %u "
"csum_flags=%b\n", __func__, m->m_len, plen, offset,
(int)m->m_pkthdr.csum_flags, CSUM_BITS);
/*
* XXX this should not happen, but if it does, the correct
* behavior may be to insert the checksum in the appropriate
* next mbuf in the chain.
*/
return;
}
*(u_short *)(m->m_data + offset) = csum;
}
int
ip6_fragment(struct ifnet *ifp, struct mbuf *m0, int hlen, u_char nextproto,
int mtu, uint32_t id)
{
struct mbuf *m, **mnext, *m_frgpart;
struct ip6_hdr *ip6, *mhip6;
struct ip6_frag *ip6f;
int off;
int error;
int tlen = m0->m_pkthdr.len;
m = m0;
ip6 = mtod(m, struct ip6_hdr *);
mnext = &m->m_nextpkt;
for (off = hlen; off < tlen; off += mtu) {
m = m_gethdr(M_NOWAIT, MT_DATA);
if (!m) {
IP6STAT_INC(ip6s_odropped);
return (ENOBUFS);
}
m->m_flags = m0->m_flags & M_COPYFLAGS;
*mnext = m;
mnext = &m->m_nextpkt;
m->m_data += max_linkhdr;
mhip6 = mtod(m, struct ip6_hdr *);
*mhip6 = *ip6;
m->m_len = sizeof(*mhip6);
error = ip6_insertfraghdr(m0, m, hlen, &ip6f);
if (error) {
IP6STAT_INC(ip6s_odropped);
return (error);
}
ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
if (off + mtu >= tlen)
mtu = tlen - off;
else
ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
mhip6->ip6_plen = htons((u_short)(mtu + hlen +
sizeof(*ip6f) - sizeof(struct ip6_hdr)));
if ((m_frgpart = m_copy(m0, off, mtu)) == 0) {
IP6STAT_INC(ip6s_odropped);
return (ENOBUFS);
}
m_cat(m, m_frgpart);
m->m_pkthdr.len = mtu + hlen + sizeof(*ip6f);
m->m_pkthdr.fibnum = m0->m_pkthdr.fibnum;
m->m_pkthdr.rcvif = NULL;
ip6f->ip6f_reserved = 0;
ip6f->ip6f_ident = id;
ip6f->ip6f_nxt = nextproto;
IP6STAT_INC(ip6s_ofragments);
in6_ifstat_inc(ifp, ifs6_out_fragcreat);
}
return (0);
}
/*
* 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.
* If route_in6 ro is present and has ro_rt initialized, route lookup would be
* skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
* then result of route lookup is stored in ro->ro_rt.
*
* type of "mtu": rt_mtu is u_long, ifnet.ifr_mtu is int, and
* nd_ifinfo.linkmtu is u_int32_t. so we use u_long to hold largest one,
* which is rt_mtu.
*
* ifpp - XXX: just for statistics
*/
/*
* XXX TODO: no flowid is assigned for outbound flows?
*/
int
ip6_output(struct mbuf *m0, struct ip6_pktopts *opt,
struct route_in6 *ro, int flags, struct ip6_moptions *im6o,
struct ifnet **ifpp, struct inpcb *inp)
{
struct ip6_hdr *ip6;
struct ifnet *ifp, *origifp;
struct mbuf *m = m0;
struct mbuf *mprev = NULL;
int hlen, tlen, len;
struct route_in6 ip6route;
struct rtentry *rt = NULL;
struct sockaddr_in6 *dst, src_sa, dst_sa;
struct in6_addr odst;
int error = 0;
struct in6_ifaddr *ia = NULL;
u_long mtu;
int alwaysfrag, dontfrag;
u_int32_t optlen = 0, plen = 0, unfragpartlen = 0;
struct ip6_exthdrs exthdrs;
struct in6_addr finaldst, src0, dst0;
u_int32_t zone;
struct route_in6 *ro_pmtu = NULL;
int hdrsplit = 0;
int sw_csum, tso;
int needfiblookup;
uint32_t fibnum;
struct m_tag *fwd_tag = NULL;
uint32_t id;
ip6 = mtod(m, struct ip6_hdr *);
if (ip6 == NULL) {
printf ("ip6 is NULL");
goto bad;
}
if (inp != NULL) {
M_SETFIB(m, inp->inp_inc.inc_fibnum);
if ((flags & IP_NODEFAULTFLOWID) == 0) {
/* unconditionally set flowid */
m->m_pkthdr.flowid = inp->inp_flowid;
M_HASHTYPE_SET(m, inp->inp_flowtype);
}
}
finaldst = ip6->ip6_dst;
bzero(&exthdrs, sizeof(exthdrs));
if (opt) {
/* Hop-by-Hop options header */
MAKE_EXTHDR(opt->ip6po_hbh, &exthdrs.ip6e_hbh);
/* Destination options header(1st part) */
if (opt->ip6po_rthdr) {
/*
* Destination options header(1st part)
* This only makes sense with a routing header.
* See Section 9.2 of RFC 3542.
* Disabling this part just for MIP6 convenience is
* a bad idea. We need to think carefully about a
* way to make the advanced API coexist with MIP6
* options, which might automatically be inserted in
* the kernel.
*/
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
/*
* IPSec checking which handles several cases.
* FAST IPSEC: We re-injected the packet.
* XXX: need scope argument.
*/
switch(ip6_ipsec_output(&m, inp, &error))
{
case 1: /* Bad packet */
goto freehdrs;
case -1: /* IPSec done */
goto done;
case 0: /* No IPSec */
default:
break;
}
#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 (done in ip6_ipsec_output) */
if (exthdrs.ip6e_dest2)
optlen += exthdrs.ip6e_dest2->m_len;
/*
* If there is at least one extension header,
* separate IP6 header from the payload.
*/
if (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;
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("assumption failed: hdr not split");
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;
}
/*
* 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, discard the packet.
*/
if (exthdrs.ip6e_rthdr) {
error = EINVAL;
goto bad;
}
/* Source address validation */
if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src) &&
(flags & IPV6_UNSPECSRC) == 0) {
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 (ro == 0) {
ro = &ip6route;
bzero((caddr_t)ro, sizeof(*ro));
}
ro_pmtu = ro;
if (opt && opt->ip6po_rthdr)
ro = &opt->ip6po_route;
dst = (struct sockaddr_in6 *)&ro->ro_dst;
#ifdef FLOWTABLE
if (ro->ro_rt == NULL)
(void )flowtable_lookup(AF_INET6, m, (struct route *)ro);
#endif
fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
again:
/*
* 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_multicast_hlim;
else
ip6->ip6_hlim = V_ip6_defmcasthlim;
}
/* adjust pointer */
ip6 = mtod(m, struct ip6_hdr *);
if (ro->ro_rt && fwd_tag == NULL) {
rt = ro->ro_rt;
ifp = ro->ro_rt->rt_ifp;
} else {
if (fwd_tag == NULL) {
bzero(&dst_sa, sizeof(dst_sa));
dst_sa.sin6_family = AF_INET6;
dst_sa.sin6_len = sizeof(dst_sa);
dst_sa.sin6_addr = ip6->ip6_dst;
}
error = in6_selectroute_fib(&dst_sa, opt, im6o, ro, &ifp,
&rt, fibnum);
if (error != 0) {
if (ifp != NULL)
in6_ifstat_inc(ifp, ifs6_out_discard);
goto bad;
}
}
if (rt == NULL) {
/*
* If in6_selectroute() does not return a route entry,
* dst may not have been updated.
*/
*dst = dst_sa; /* XXX */
}
/*
* then rt (for unicast) and ifp must be non-NULL valid values.
*/
if ((flags & IPV6_FORWARDING) == 0) {
/* XXX: the FORWARDING flag can be set for mrouting. */
in6_ifstat_inc(ifp, ifs6_out_request);
}
if (rt != NULL) {
ia = (struct in6_ifaddr *)(rt->rt_ifa);
counter_u64_add(rt->rt_pksent, 1);
}
/*
* The outgoing interface must be in the zone of source and
* destination addresses.
*/
origifp = ifp;
src0 = ip6->ip6_src;
if (in6_setscope(&src0, origifp, &zone))
goto badscope;
bzero(&src_sa, sizeof(src_sa));
src_sa.sin6_family = AF_INET6;
src_sa.sin6_len = sizeof(src_sa);
src_sa.sin6_addr = ip6->ip6_src;
if (sa6_recoverscope(&src_sa) || zone != src_sa.sin6_scope_id)
goto badscope;
dst0 = ip6->ip6_dst;
if (in6_setscope(&dst0, origifp, &zone))
goto badscope;
/* re-initialize to be sure */
bzero(&dst_sa, sizeof(dst_sa));
dst_sa.sin6_family = AF_INET6;
dst_sa.sin6_len = sizeof(dst_sa);
dst_sa.sin6_addr = ip6->ip6_dst;
if (sa6_recoverscope(&dst_sa) || zone != dst_sa.sin6_scope_id) {
goto badscope;
}
/* We should use ia_ifp to support the case of
* sending packets to an address of our own.
*/
if (ia != NULL && ia->ia_ifp)
ifp = ia->ia_ifp;
/* scope check is done. */
goto routefound;
badscope:
IP6STAT_INC(ip6s_badscope);
in6_ifstat_inc(origifp, ifs6_out_discard);
if (error == 0)
error = EHOSTUNREACH; /* XXX */
goto bad;
routefound:
if (rt && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
if (opt && opt->ip6po_nextroute.ro_rt) {
/*
* The nexthop is explicitly specified by the
* application. We assume the next hop is an IPv6
* address.
*/
dst = (struct sockaddr_in6 *)opt->ip6po_nexthop;
}
else if ((rt->rt_flags & RTF_GATEWAY))
dst = (struct sockaddr_in6 *)rt->rt_gateway;
}
if (!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
m->m_flags &= ~(M_BCAST | M_MCAST); /* just in case */
} else {
m->m_flags = (m->m_flags & ~M_BCAST) | M_MCAST;
in6_ifstat_inc(ifp, ifs6_out_mcast);
/*
* Confirm that the outgoing interface supports multicast.
*/
if (!(ifp->if_flags & IFF_MULTICAST)) {
IP6STAT_INC(ip6s_noroute);
in6_ifstat_inc(ifp, ifs6_out_discard);
error = ENETUNREACH;
goto bad;
}
if ((im6o == NULL && in6_mcast_loop) ||
(im6o && im6o->im6o_multicast_loop)) {
/*
* Loop back multicast datagram if not expressly
* forbidden to do so, even if we have not joined
* the address; protocols will filter it later,
* thus deferring a hash lookup and lock acquisition
* at the expense of an m_copym().
*/
ip6_mloopback(ifp, m);
} 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 (V_ip6_mrouter && (flags & IPV6_FORWARDING) == 0) {
/*
* XXX: ip6_mforward expects that rcvif is NULL
* when it is called from the originating path.
* However, it may not always be the case.
*/
m->m_pkthdr.rcvif = NULL;
if (ip6_mforward(ip6, ifp, m) != 0) {
m_freem(m);
goto done;
}
}
}
/*
* 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;
}
}
/*
* Fill the outgoing inteface to tell the upper layer
* to increment per-interface statistics.
*/
if (ifpp)
*ifpp = ifp;
/* Determine path MTU. */
if ((error = ip6_getpmtu(ro_pmtu, ro, ifp, &finaldst, &mtu,
&alwaysfrag, fibnum)) != 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;
}
}
/*
* clear embedded scope identifiers if necessary.
* in6_clearscope will touch the addresses only when necessary.
*/
in6_clearscope(&ip6->ip6_src);
in6_clearscope(&ip6->ip6_dst);
/*
* 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 dummy; /* XXX unused */
u_int32_t plen = 0; /* XXX: ip6_process will check the value */
#ifdef DIAGNOSTIC
if ((hbh->ip6h_len + 1) << 3 > exthdrs.ip6e_hbh->m_len)
panic("ip6e_hbh is not contiguous");
#endif
/*
* XXX: if we have to send an ICMPv6 error to the sender,
* we need the M_LOOP flag since icmp6_error() expects
* the IPv6 and the hop-by-hop options header are
* contiguous unless the flag is set.
*/
m->m_flags |= M_LOOP;
m->m_pkthdr.rcvif = ifp;
if (ip6_process_hopopts(m, (u_int8_t *)(hbh + 1),
((hbh->ip6h_len + 1) << 3) - sizeof(struct ip6_hbh),
&dummy, &plen) < 0) {
/* m was already freed at this point */
error = EINVAL;/* better error? */
goto done;
}
m->m_flags &= ~M_LOOP; /* XXX */
m->m_pkthdr.rcvif = NULL;
}
/* Jump over all PFIL processing if hooks are not active. */
if (!PFIL_HOOKED(&V_inet6_pfil_hook))
goto passout;
odst = ip6->ip6_dst;
/* Run through list of hooks for output packets. */
error = pfil_run_hooks(&V_inet6_pfil_hook, &m, ifp, PFIL_OUT, inp);
if (error != 0 || m == NULL)
goto done;
ip6 = mtod(m, struct ip6_hdr *);
needfiblookup = 0;
/* See if destination IP address was changed by packet filter. */
if (!IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst)) {
m->m_flags |= M_SKIP_FIREWALL;
/* If destination is now ourself drop to ip6_input(). */
if (in6_localip(&ip6->ip6_dst)) {
m->m_flags |= M_FASTFWD_OURS;
if (m->m_pkthdr.rcvif == NULL)
m->m_pkthdr.rcvif = V_loif;
if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
m->m_pkthdr.csum_flags |=
CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
m->m_pkthdr.csum_data = 0xffff;
}
#ifdef SCTP
if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
#endif
error = netisr_queue(NETISR_IPV6, m);
goto done;
} else
needfiblookup = 1; /* Redo the routing table lookup. */
}
/* See if fib was changed by packet filter. */
if (fibnum != M_GETFIB(m)) {
m->m_flags |= M_SKIP_FIREWALL;
fibnum = M_GETFIB(m);
RO_RTFREE(ro);
needfiblookup = 1;
}
if (needfiblookup)
goto again;
/* See if local, if yes, send it to netisr. */
if (m->m_flags & M_FASTFWD_OURS) {
if (m->m_pkthdr.rcvif == NULL)
m->m_pkthdr.rcvif = V_loif;
if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
m->m_pkthdr.csum_flags |=
CSUM_DATA_VALID_IPV6 | CSUM_PSEUDO_HDR;
m->m_pkthdr.csum_data = 0xffff;
}
#ifdef SCTP
if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6)
m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
#endif
error = netisr_queue(NETISR_IPV6, m);
goto done;
}
/* Or forward to some other address? */
if ((m->m_flags & M_IP6_NEXTHOP) &&
(fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
dst = (struct sockaddr_in6 *)&ro->ro_dst;
bcopy((fwd_tag+1), &dst_sa, sizeof(struct sockaddr_in6));
m->m_flags |= M_SKIP_FIREWALL;
m->m_flags &= ~M_IP6_NEXTHOP;
m_tag_delete(m, fwd_tag);
goto again;
}
passout:
/*
* 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, alwaysfrag == 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
*
* 3: if we always need to attach fragment header (alwaysfrag == 1)
* always fragment
*
* 4: if dontfrag == 1 && alwaysfrag == 1
* error, as we cannot handle this conflicting request
*/
sw_csum = m->m_pkthdr.csum_flags;
if (!hdrsplit) {
tso = ((sw_csum & ifp->if_hwassist & CSUM_TSO) != 0) ? 1 : 0;
sw_csum &= ~ifp->if_hwassist;
} else
tso = 0;
/*
* If we added extension headers, we will not do TSO and calculate the
* checksums ourselves for now.
* XXX-BZ Need a framework to know when the NIC can handle it, even
* with ext. hdrs.
*/
if (sw_csum & CSUM_DELAY_DATA_IPV6) {
sw_csum &= ~CSUM_DELAY_DATA_IPV6;
in6_delayed_cksum(m, plen, sizeof(struct ip6_hdr));
}
#ifdef SCTP
if (sw_csum & CSUM_SCTP_IPV6) {
sw_csum &= ~CSUM_SCTP_IPV6;
sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
}
#endif
m->m_pkthdr.csum_flags &= ifp->if_hwassist;
tlen = m->m_pkthdr.len;
if ((opt && (opt->ip6po_flags & IP6PO_DONTFRAG)) || tso)
dontfrag = 1;
else
dontfrag = 0;
if (dontfrag && alwaysfrag) { /* case 4 */
/* conflicting request - can't transmit */
error = EMSGSIZE;
goto bad;
}
if (dontfrag && tlen > IN6_LINKMTU(ifp) && !tso) { /* case 2-b */
/*
* Even if the DONTFRAG option is specified, we cannot send the
* packet when the data length is larger than the MTU of the
* outgoing interface.
* Notify the error by sending IPV6_PATHMTU ancillary data if
* application wanted to know the MTU value. Also return an
* error code (this is not described in the API spec).
*/
if (inp != NULL)
ip6_notify_pmtu(inp, &dst_sa, (u_int32_t)mtu);
error = EMSGSIZE;
goto bad;
}
/*
* transmit packet without fragmentation
*/
if (dontfrag || (!alwaysfrag && tlen <= mtu)) { /* case 1-a and 2-a */
struct in6_ifaddr *ia6;
ip6 = mtod(m, struct ip6_hdr *);
ia6 = in6_ifawithifp(ifp, &ip6->ip6_src);
if (ia6) {
/* Record statistics for this interface address. */
counter_u64_add(ia6->ia_ifa.ifa_opackets, 1);
counter_u64_add(ia6->ia_ifa.ifa_obytes,
m->m_pkthdr.len);
ifa_free(&ia6->ia_ifa);
}
error = nd6_output_ifp(ifp, origifp, m, dst);
goto done;
}
/*
* try to fragment the packet. case 1-b and 3
*/
if (mtu < IPV6_MMTU) {
/* path MTU cannot be less than IPV6_MMTU */
error = EMSGSIZE;
in6_ifstat_inc(ifp, ifs6_out_fragfail);
goto bad;
} else if (ip6->ip6_plen == 0) {
/* jumbo payload cannot be fragmented */
error = EMSGSIZE;
in6_ifstat_inc(ifp, ifs6_out_fragfail);
goto bad;
} else {
u_char nextproto;
/*
* 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;
len = (mtu - hlen - sizeof(struct ip6_frag)) & ~7;
if (len < 8) {
error = EMSGSIZE;
in6_ifstat_inc(ifp, ifs6_out_fragfail);
goto bad;
}
/*
* If the interface will not calculate checksums on
* fragmented packets, then do it here.
* XXX-BZ handle the hw offloading case. Need flags.
*/
if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
in6_delayed_cksum(m, plen, hlen);
m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
}
#ifdef SCTP
if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
sctp_delayed_cksum(m, hlen);
m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
}
#endif
/*
* 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;
}
/*
* Loop through length of segment after first fragment,
* make new header and copy data of each part and link onto
* chain.
*/
m0 = m;
id = htonl(ip6_randomid());
if ((error = ip6_fragment(ifp, m, hlen, nextproto, len, id)))
goto sendorfree;
in6_ifstat_inc(ifp, ifs6_out_fragok);
}
/*
* Remove leading garbages.
*/
sendorfree:
m = m0->m_nextpkt;
m0->m_nextpkt = 0;
m_freem(m0);
for (m0 = m; m; m = m0) {
m0 = m->m_nextpkt;
m->m_nextpkt = 0;
if (error == 0) {
/* Record statistics for this interface address. */
if (ia) {
counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
counter_u64_add(ia->ia_ifa.ifa_obytes,
m->m_pkthdr.len);
}
error = nd6_output_ifp(ifp, origifp, m, dst);
} else
m_freem(m);
}
if (error == 0)
IP6STAT_INC(ip6s_fragmented);
done:
if (ro == &ip6route)
RO_RTFREE(ro);
if (ro_pmtu == &ip6route)
RO_RTFREE(ro_pmtu);
return (error);
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);
/* FALLTHROUGH */
bad:
if (m)
m_freem(m);
goto done;
}
static int
ip6_copyexthdr(struct mbuf **mp, caddr_t hdr, int hlen)
{
struct mbuf *m;
if (hlen > MCLBYTES)
return (ENOBUFS); /* XXX */
if (hlen > MLEN)
m = m_getcl(M_NOWAIT, MT_DATA, 0);
else
m = m_get(M_NOWAIT, MT_DATA);
if (m == NULL)
return (ENOBUFS);
m->m_len = hlen;
if (hdr)
bcopy(hdr, mtod(m, caddr_t), hlen);
*mp = m;
return (0);
}
/*
* Insert jumbo payload option.
*/
static int
ip6_insert_jumboopt(struct ip6_exthdrs *exthdrs, u_int32_t plen)
{
struct mbuf *mopt;
u_char *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) {
mopt = m_get(M_NOWAIT, MT_DATA);
if (mopt == NULL)
return (ENOBUFS);
mopt->m_len = JUMBOOPTLEN;
optbuf = mtod(mopt, u_char *);
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.
*/
n = m_getcl(M_NOWAIT, MT_DATA, 0);
if (n == NULL)
return (ENOBUFS);
n->m_len = oldoptlen + JUMBOOPTLEN;
bcopy(mtod(mopt, caddr_t), mtod(n, caddr_t),
oldoptlen);
optbuf = mtod(n, caddr_t) + oldoptlen;
m_freem(mopt);
mopt = exthdrs->ip6e_hbh = n;
} else {
optbuf = mtod(mopt, u_char *) + mopt->m_len;
mopt->m_len += JUMBOOPTLEN;
}
optbuf[0] = IP6OPT_PADN;
optbuf[1] = 1;
/*
* 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);
bcopy(&v, &optbuf[4], 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.
*/
static 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_NOWAIT);
if (n == 0)
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 (M_WRITABLE(mlast) &&
M_TRAILINGSPACE(mlast) >= sizeof(struct ip6_frag)) {
/* use the trailing space of the last mbuf for the 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;
mfrg = m_get(M_NOWAIT, 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);
}
static int
ip6_getpmtu(struct route_in6 *ro_pmtu, struct route_in6 *ro,
struct ifnet *ifp, struct in6_addr *dst, u_long *mtup,
int *alwaysfragp, u_int fibnum)
{
u_int32_t mtu = 0;
int alwaysfrag = 0;
int error = 0;
if (ro_pmtu != ro) {
/* The first hop and the final destination may differ. */
struct sockaddr_in6 *sa6_dst =
(struct sockaddr_in6 *)&ro_pmtu->ro_dst;
if (ro_pmtu->ro_rt &&
((ro_pmtu->ro_rt->rt_flags & RTF_UP) == 0 ||
!IN6_ARE_ADDR_EQUAL(&sa6_dst->sin6_addr, dst))) {
RTFREE(ro_pmtu->ro_rt);
ro_pmtu->ro_rt = (struct rtentry *)NULL;
}
if (ro_pmtu->ro_rt == NULL) {
bzero(sa6_dst, sizeof(*sa6_dst));
sa6_dst->sin6_family = AF_INET6;
sa6_dst->sin6_len = sizeof(struct sockaddr_in6);
sa6_dst->sin6_addr = *dst;
in6_rtalloc(ro_pmtu, fibnum);
}
}
if (ro_pmtu->ro_rt) {
u_int32_t ifmtu;
struct in_conninfo inc;
bzero(&inc, sizeof(inc));
inc.inc_flags |= INC_ISIPV6;
inc.inc6_faddr = *dst;
if (ifp == NULL)
ifp = ro_pmtu->ro_rt->rt_ifp;
ifmtu = IN6_LINKMTU(ifp);
mtu = tcp_hc_getmtu(&inc);
if (mtu)
mtu = min(mtu, ro_pmtu->ro_rt->rt_mtu);
else
mtu = ro_pmtu->ro_rt->rt_mtu;
if (mtu == 0)
mtu = ifmtu;
else if (mtu < IPV6_MMTU) {
/*
* RFC2460 section 5, last paragraph:
* if we record ICMPv6 too big message with
* mtu < IPV6_MMTU, transmit packets sized IPV6_MMTU
* or smaller, with framgent header attached.
* (fragment header is needed regardless from the
* packet size, for translators to identify packets)
*/
alwaysfrag = 1;
mtu = IPV6_MMTU;
}
} else if (ifp) {
mtu = IN6_LINKMTU(ifp);
} else
error = EHOSTUNREACH; /* XXX */
*mtup = mtu;
if (alwaysfragp)
*alwaysfragp = alwaysfrag;
return (error);
}
/*
* IP6 socket option processing.
*/
int
ip6_ctloutput(struct socket *so, struct sockopt *sopt)
{
int optdatalen, uproto;
void *optdata;
struct inpcb *in6p = sotoinpcb(so);
int error, optval;
int level, op, optname;
int optlen;
struct thread *td;
#ifdef RSS
uint32_t rss_bucket;
int retval;
#endif
level = sopt->sopt_level;
op = sopt->sopt_dir;
optname = sopt->sopt_name;
optlen = sopt->sopt_valsize;
td = sopt->sopt_td;
error = 0;
optval = 0;
uproto = (int)so->so_proto->pr_protocol;
if (level != IPPROTO_IPV6) {
error = EINVAL;
if (sopt->sopt_level == SOL_SOCKET &&
sopt->sopt_dir == SOPT_SET) {
switch (sopt->sopt_name) {
case SO_REUSEADDR:
INP_WLOCK(in6p);
if ((so->so_options & SO_REUSEADDR) != 0)
in6p->inp_flags2 |= INP_REUSEADDR;
else
in6p->inp_flags2 &= ~INP_REUSEADDR;
INP_WUNLOCK(in6p);
error = 0;
break;
case SO_REUSEPORT:
INP_WLOCK(in6p);
if ((so->so_options & SO_REUSEPORT) != 0)
in6p->inp_flags2 |= INP_REUSEPORT;
else
in6p->inp_flags2 &= ~INP_REUSEPORT;
INP_WUNLOCK(in6p);
error = 0;
break;
case SO_SETFIB:
INP_WLOCK(in6p);
in6p->inp_inc.inc_fibnum = so->so_fibnum;
INP_WUNLOCK(in6p);
error = 0;
break;
default:
break;
}
}
} else { /* level == IPPROTO_IPV6 */
switch (op) {
case SOPT_SET:
switch (optname) {
case IPV6_2292PKTOPTIONS:
#ifdef IPV6_PKTOPTIONS
case IPV6_PKTOPTIONS:
#endif
{
struct mbuf *m;
error = soopt_getm(sopt, &m); /* XXX */
if (error != 0)
break;
error = soopt_mcopyin(sopt, m); /* XXX */
if (error != 0)
break;
error = ip6_pcbopts(&in6p->in6p_outputopts,
m, so, sopt);
m_freem(m); /* XXX */
break;
}
/*
* 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:
case IPV6_RECVRTHDRDSTOPTS:
if (td != NULL) {
error = priv_check(td,
PRIV_NETINET_SETHDROPTS);
if (error)
break;
}
/* FALLTHROUGH */
case IPV6_UNICAST_HOPS:
case IPV6_HOPLIMIT:
case IPV6_RECVPKTINFO:
case IPV6_RECVHOPLIMIT:
case IPV6_RECVRTHDR:
case IPV6_RECVPATHMTU:
case IPV6_RECVTCLASS:
case IPV6_RECVFLOWID:
#ifdef RSS
case IPV6_RECVRSSBUCKETID:
#endif
case IPV6_V6ONLY:
case IPV6_AUTOFLOWLABEL:
case IPV6_BINDANY:
case IPV6_BINDMULTI:
#ifdef RSS
case IPV6_RSS_LISTEN_BUCKET:
#endif
if (optname == IPV6_BINDANY && td != NULL) {
error = priv_check(td,
PRIV_NETINET_BINDANY);
if (error)
break;
}
if (optlen != sizeof(int)) {
error = EINVAL;
break;
}
error = sooptcopyin(sopt, &optval,
sizeof optval, sizeof optval);
if (error)
break;
switch (optname) {
case IPV6_UNICAST_HOPS:
if (optval < -1 || optval >= 256)
error = EINVAL;
else {
/* -1 = kernel default */
in6p->in6p_hops = optval;
if ((in6p->inp_vflag &
INP_IPV4) != 0)
in6p->inp_ip_ttl = optval;
}
break;
#define OPTSET(bit) \
do { \
INP_WLOCK(in6p); \
if (optval) \
in6p->inp_flags |= (bit); \
else \
in6p->inp_flags &= ~(bit); \
INP_WUNLOCK(in6p); \
} while (/*CONSTCOND*/ 0)
#define OPTSET2292(bit) \
do { \
INP_WLOCK(in6p); \
in6p->inp_flags |= IN6P_RFC2292; \
if (optval) \
in6p->inp_flags |= (bit); \
else \
in6p->inp_flags &= ~(bit); \
INP_WUNLOCK(in6p); \
} while (/*CONSTCOND*/ 0)
#define OPTBIT(bit) (in6p->inp_flags & (bit) ? 1 : 0)
#define OPTSET2(bit, val) do { \
INP_WLOCK(in6p); \
if (val) \
in6p->inp_flags2 |= bit; \
else \
in6p->inp_flags2 &= ~bit; \
INP_WUNLOCK(in6p); \
} while (0)
#define OPTBIT2(bit) (in6p->inp_flags2 & (bit) ? 1 : 0)
case IPV6_RECVPKTINFO:
/* cannot mix with RFC2292 */
if (OPTBIT(IN6P_RFC2292)) {
error = EINVAL;
break;
}
OPTSET(IN6P_PKTINFO);
break;
case IPV6_HOPLIMIT:
{
struct ip6_pktopts **optp;
/* cannot mix with RFC2292 */
if (OPTBIT(IN6P_RFC2292)) {
error = EINVAL;
break;
}
optp = &in6p->in6p_outputopts;
error = ip6_pcbopt(IPV6_HOPLIMIT,
(u_char *)&optval, sizeof(optval),
optp, (td != NULL) ? td->td_ucred :
NULL, uproto);
break;
}
case IPV6_RECVHOPLIMIT:
/* cannot mix with RFC2292 */
if (OPTBIT(IN6P_RFC2292)) {
error = EINVAL;
break;
}
OPTSET(IN6P_HOPLIMIT);
break;
case IPV6_RECVHOPOPTS:
/* cannot mix with RFC2292 */
if (OPTBIT(IN6P_RFC2292)) {
error = EINVAL;
break;
}
OPTSET(IN6P_HOPOPTS);
break;
case IPV6_RECVDSTOPTS:
/* cannot mix with RFC2292 */
if (OPTBIT(IN6P_RFC2292)) {
error = EINVAL;
break;
}
OPTSET(IN6P_DSTOPTS);
break;
case IPV6_RECVRTHDRDSTOPTS:
/* cannot mix with RFC2292 */
if (OPTBIT(IN6P_RFC2292)) {
error = EINVAL;
break;
}
OPTSET(IN6P_RTHDRDSTOPTS);
break;
case IPV6_RECVRTHDR:
/* cannot mix with RFC2292 */
if (OPTBIT(IN6P_RFC2292)) {
error = EINVAL;
break;
}
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_RECVFLOWID:
OPTSET2(INP_RECVFLOWID, optval);
break;
#ifdef RSS
case IPV6_RECVRSSBUCKETID:
OPTSET2(INP_RECVRSSBUCKETID, optval);
break;
#endif
case IPV6_V6ONLY:
/*
* make setsockopt(IPV6_V6ONLY)
* available only prior to bind(2).
* see ipng mailing list, Jun 22 2001.
*/
if (in6p->inp_lport ||
!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
error = EINVAL;
break;
}
OPTSET(IN6P_IPV6_V6ONLY);
if (optval)
in6p->inp_vflag &= ~INP_IPV4;
else
in6p->inp_vflag |= INP_IPV4;
break;
case IPV6_RECVTCLASS:
/* cannot mix with RFC2292 XXX */
if (OPTBIT(IN6P_RFC2292)) {
error = EINVAL;
break;
}
OPTSET(IN6P_TCLASS);
break;
case IPV6_AUTOFLOWLABEL:
OPTSET(IN6P_AUTOFLOWLABEL);
break;
case IPV6_BINDANY:
OPTSET(INP_BINDANY);
break;
case IPV6_BINDMULTI:
OPTSET2(INP_BINDMULTI, optval);
break;
#ifdef RSS
case IPV6_RSS_LISTEN_BUCKET:
if ((optval >= 0) &&
(optval < rss_getnumbuckets())) {
in6p->inp_rss_listen_bucket = optval;
OPTSET2(INP_RSS_BUCKET_SET, 1);
} else {
error = EINVAL;
}
break;
#endif
}
break;
case IPV6_TCLASS:
case IPV6_DONTFRAG:
case IPV6_USE_MIN_MTU:
case IPV6_PREFER_TEMPADDR:
if (optlen != sizeof(optval)) {
error = EINVAL;
break;
}
error = sooptcopyin(sopt, &optval,
sizeof optval, sizeof optval);
if (error)
break;
{
struct ip6_pktopts **optp;
optp = &in6p->in6p_outputopts;
error = ip6_pcbopt(optname,
(u_char *)&optval, sizeof(optval),
optp, (td != NULL) ? td->td_ucred :
NULL, uproto);
break;
}
case IPV6_2292PKTINFO:
case IPV6_2292HOPLIMIT:
case IPV6_2292HOPOPTS:
case IPV6_2292DSTOPTS:
case IPV6_2292RTHDR:
/* RFC 2292 */
if (optlen != sizeof(int)) {
error = EINVAL;
break;
}
error = sooptcopyin(sopt, &optval,
sizeof optval, sizeof optval);
if (error)
break;
switch (optname) {
case IPV6_2292PKTINFO:
OPTSET2292(IN6P_PKTINFO);
break;
case IPV6_2292HOPLIMIT:
OPTSET2292(IN6P_HOPLIMIT);
break;
case IPV6_2292HOPOPTS:
/*
* Check super-user privilege.
* See comments for IPV6_RECVHOPOPTS.
*/
if (td != NULL) {
error = priv_check(td,
PRIV_NETINET_SETHDROPTS);
if (error)
return (error);
}
OPTSET2292(IN6P_HOPOPTS);
break;
case IPV6_2292DSTOPTS:
if (td != NULL) {
error = priv_check(td,
PRIV_NETINET_SETHDROPTS);
if (error)
return (error);
}
OPTSET2292(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS); /* XXX */
break;
case IPV6_2292RTHDR:
OPTSET2292(IN6P_RTHDR);
break;
}
break;
case IPV6_PKTINFO:
case IPV6_HOPOPTS:
case IPV6_RTHDR:
case IPV6_DSTOPTS:
case IPV6_RTHDRDSTOPTS:
case IPV6_NEXTHOP:
{
/* new advanced API (RFC3542) */
u_char *optbuf;
u_char optbuf_storage[MCLBYTES];
int optlen;
struct ip6_pktopts **optp;
/* cannot mix with RFC2292 */
if (OPTBIT(IN6P_RFC2292)) {
error = EINVAL;
break;
}
/*
* We only ensure valsize is not too large
* here. Further validation will be done
* later.
*/
error = sooptcopyin(sopt, optbuf_storage,
sizeof(optbuf_storage), 0);
if (error)
break;
optlen = sopt->sopt_valsize;
optbuf = optbuf_storage;
optp = &in6p->in6p_outputopts;
error = ip6_pcbopt(optname, optbuf, optlen,
optp, (td != NULL) ? td->td_ucred : NULL,
uproto);
break;
}
#undef OPTSET
case IPV6_MULTICAST_IF:
case IPV6_MULTICAST_HOPS:
case IPV6_MULTICAST_LOOP:
case IPV6_JOIN_GROUP:
case IPV6_LEAVE_GROUP:
case IPV6_MSFILTER:
case MCAST_BLOCK_SOURCE:
case MCAST_UNBLOCK_SOURCE:
case MCAST_JOIN_GROUP:
case MCAST_LEAVE_GROUP:
case MCAST_JOIN_SOURCE_GROUP:
case MCAST_LEAVE_SOURCE_GROUP:
error = ip6_setmoptions(in6p, sopt);
break;
case IPV6_PORTRANGE:
error = sooptcopyin(sopt, &optval,
sizeof optval, sizeof optval);
if (error)
break;
INP_WLOCK(in6p);
switch (optval) {
case IPV6_PORTRANGE_DEFAULT:
in6p->inp_flags &= ~(INP_LOWPORT);
in6p->inp_flags &= ~(INP_HIGHPORT);
break;
case IPV6_PORTRANGE_HIGH:
in6p->inp_flags &= ~(INP_LOWPORT);
in6p->inp_flags |= INP_HIGHPORT;
break;
case IPV6_PORTRANGE_LOW:
in6p->inp_flags &= ~(INP_HIGHPORT);
in6p->inp_flags |= INP_LOWPORT;
break;
default:
error = EINVAL;
break;
}
INP_WUNLOCK(in6p);
break;
#ifdef IPSEC
case IPV6_IPSEC_POLICY:
{
caddr_t req;
struct mbuf *m;
if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
break;
if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
break;
req = mtod(m, caddr_t);
error = ipsec_set_policy(in6p, optname, req,
m->m_len, (sopt->sopt_td != NULL) ?
sopt->sopt_td->td_ucred : NULL);
m_freem(m);
break;
}
#endif /* IPSEC */
default:
error = ENOPROTOOPT;
break;
}
break;
case SOPT_GET:
switch (optname) {
case IPV6_2292PKTOPTIONS:
#ifdef IPV6_PKTOPTIONS
case IPV6_PKTOPTIONS:
#endif
/*
* RFC3542 (effectively) deprecated the
* semantics of the 2292-style pktoptions.
* Since it was not reliable in nature (i.e.,
* applications had to expect the lack of some
* information after all), it would make sense
* to simplify this part by always returning
* empty data.
*/
sopt->sopt_valsize = 0;
break;
case IPV6_RECVHOPOPTS:
case IPV6_RECVDSTOPTS:
case IPV6_RECVRTHDRDSTOPTS:
case IPV6_UNICAST_HOPS:
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_BINDANY:
case IPV6_FLOWID:
case IPV6_FLOWTYPE:
case IPV6_RECVFLOWID:
#ifdef RSS
case IPV6_RSSBUCKETID:
case IPV6_RECVRSSBUCKETID:
#endif
switch (optname) {
case IPV6_RECVHOPOPTS:
optval = OPTBIT(IN6P_HOPOPTS);
break;
case IPV6_RECVDSTOPTS:
optval = OPTBIT(IN6P_DSTOPTS);
break;
case IPV6_RECVRTHDRDSTOPTS:
optval = OPTBIT(IN6P_RTHDRDSTOPTS);
break;
case IPV6_UNICAST_HOPS:
optval = in6p->in6p_hops;
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 = OPTBIT(IN6P_IPV6_V6ONLY);
break;
case IPV6_PORTRANGE:
{
int flags;
flags = in6p->inp_flags;
if (flags & INP_HIGHPORT)
optval = IPV6_PORTRANGE_HIGH;
else if (flags & INP_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_BINDANY:
optval = OPTBIT(INP_BINDANY);
break;
case IPV6_FLOWID:
optval = in6p->inp_flowid;
break;
case IPV6_FLOWTYPE:
optval = in6p->inp_flowtype;
break;
case IPV6_RECVFLOWID:
optval = OPTBIT2(INP_RECVFLOWID);
break;
#ifdef RSS
case IPV6_RSSBUCKETID:
retval =
rss_hash2bucket(in6p->inp_flowid,
in6p->inp_flowtype,
&rss_bucket);
if (retval == 0)
optval = rss_bucket;
else
error = EINVAL;
break;
case IPV6_RECVRSSBUCKETID:
optval = OPTBIT2(INP_RECVRSSBUCKETID);
break;
#endif
case IPV6_BINDMULTI:
optval = OPTBIT2(INP_BINDMULTI);
break;
}
if (error)
break;
error = sooptcopyout(sopt, &optval,
sizeof optval);
break;
case IPV6_PATHMTU:
{
u_long pmtu = 0;
struct ip6_mtuinfo mtuinfo;
struct route_in6 sro;
bzero(&sro, sizeof(sro));
if (!(so->so_state & SS_ISCONNECTED))
return (ENOTCONN);
/*
* XXX: we dot not consider the case of source
* routing, or optional information to specify
* the outgoing interface.
*/
error = ip6_getpmtu(&sro, NULL, NULL,
&in6p->in6p_faddr, &pmtu, NULL,
so->so_fibnum);
if (sro.ro_rt)
RTFREE(sro.ro_rt);
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);
error = sooptcopyout(sopt, optdata,
optdatalen);
break;
}
case IPV6_2292PKTINFO:
case IPV6_2292HOPLIMIT:
case IPV6_2292HOPOPTS:
case IPV6_2292RTHDR:
case IPV6_2292DSTOPTS:
switch (optname) {
case IPV6_2292PKTINFO:
optval = OPTBIT(IN6P_PKTINFO);
break;
case IPV6_2292HOPLIMIT:
optval = OPTBIT(IN6P_HOPLIMIT);
break;
case IPV6_2292HOPOPTS:
optval = OPTBIT(IN6P_HOPOPTS);
break;
case IPV6_2292RTHDR:
optval = OPTBIT(IN6P_RTHDR);
break;
case IPV6_2292DSTOPTS:
optval = OPTBIT(IN6P_DSTOPTS|IN6P_RTHDRDSTOPTS);
break;
}
error = sooptcopyout(sopt, &optval,
sizeof optval);
break;
case IPV6_PKTINFO:
case IPV6_HOPOPTS:
case IPV6_RTHDR:
case IPV6_DSTOPTS:
case IPV6_RTHDRDSTOPTS:
case IPV6_NEXTHOP:
case IPV6_TCLASS:
case IPV6_DONTFRAG:
case IPV6_USE_MIN_MTU:
case IPV6_PREFER_TEMPADDR:
error = ip6_getpcbopt(in6p->in6p_outputopts,
optname, sopt);
break;
case IPV6_MULTICAST_IF:
case IPV6_MULTICAST_HOPS:
case IPV6_MULTICAST_LOOP:
case IPV6_MSFILTER:
error = ip6_getmoptions(in6p, sopt);
break;
#ifdef IPSEC
case IPV6_IPSEC_POLICY:
{
caddr_t req = NULL;
size_t len = 0;
struct mbuf *m = NULL;
struct mbuf **mp = &m;
size_t ovalsize = sopt->sopt_valsize;
caddr_t oval = (caddr_t)sopt->sopt_val;
error = soopt_getm(sopt, &m); /* XXX */
if (error != 0)
break;
error = soopt_mcopyin(sopt, m); /* XXX */
if (error != 0)
break;
sopt->sopt_valsize = ovalsize;
sopt->sopt_val = oval;
if (m) {
req = mtod(m, caddr_t);
len = m->m_len;
}
error = ipsec_get_policy(in6p, req, len, mp);
if (error == 0)
error = soopt_mcopyout(sopt, m); /* XXX */
if (error == 0 && m)
m_freem(m);
break;
}
#endif /* IPSEC */
default:
error = ENOPROTOOPT;
break;
}
break;
}
}
return (error);
}
int
ip6_raw_ctloutput(struct socket *so, struct sockopt *sopt)
{
int error = 0, optval, optlen;
const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
struct inpcb *in6p = sotoinpcb(so);
int level, op, optname;
level = sopt->sopt_level;
op = sopt->sopt_dir;
optname = sopt->sopt_name;
optlen = sopt->sopt_valsize;
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 SOPT_SET:
if (optlen != sizeof(int)) {
error = EINVAL;
break;
}
error = sooptcopyin(sopt, &optval, sizeof(optval),
sizeof(optval));
if (error)
break;
if ((optval % 2) != 0) {
/* the API assumes even offset values */
error = EINVAL;
} else if (so->so_proto->pr_protocol ==
IPPROTO_ICMPV6) {
if (optval != icmp6off)
error = EINVAL;
} else
in6p->in6p_cksum = optval;
break;
case SOPT_GET:
if (so->so_proto->pr_protocol == IPPROTO_ICMPV6)
optval = icmp6off;
else
optval = in6p->in6p_cksum;
error = sooptcopyout(sopt, &optval, sizeof(optval));
break;
default:
error = EINVAL;
break;
}
break;
default:
error = ENOPROTOOPT;
break;
}
return (error);
}
/*
* Set up IP6 options in pcb for insertion in output packets or
* specifying behavior of outgoing packets.
*/
static int
ip6_pcbopts(struct ip6_pktopts **pktopt, struct mbuf *m,
struct socket *so, struct sockopt *sopt)
{
struct ip6_pktopts *opt = *pktopt;
int error = 0;
struct thread *td = sopt->sopt_td;
/* turn off any old options. */
if (opt) {
#ifdef DIAGNOSTIC
if (opt->ip6po_pktinfo || opt->ip6po_nexthop ||
opt->ip6po_hbh || opt->ip6po_dest1 || opt->ip6po_dest2 ||
opt->ip6po_rhinfo.ip6po_rhi_rthdr)
printf("ip6_pcbopts: all specified options are cleared.\n");
#endif
ip6_clearpktopts(opt, -1);
} else
opt = malloc(sizeof(*opt), M_IP6OPT, M_WAITOK);
*pktopt = NULL;
if (!m || m->m_len == 0) {
/*
* Only turning off any previous options, regardless of
* whether the opt is just created or given.
*/
free(opt, M_IP6OPT);
return (0);
}
/* set options specified by user. */
if ((error = ip6_setpktopts(m, opt, NULL, (td != NULL) ?
td->td_ucred : NULL, so->so_proto->pr_protocol)) != 0) {
ip6_clearpktopts(opt, -1); /* XXX: discard all options */
free(opt, M_IP6OPT);
return (error);
}
*pktopt = opt;
return (0);
}
/*
* 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;
opt->ip6po_prefer_tempaddr = IP6PO_TEMPADDR_SYSTEM;
}
static int
ip6_pcbopt(int optname, u_char *buf, int len, struct ip6_pktopts **pktopt,
struct ucred *cred, 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, cred, 1, 0, uproto));
}
static int
ip6_getpcbopt(struct ip6_pktopts *pktopt, int optname, struct sockopt *sopt)
{
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;
int defpreftemp = IP6PO_TEMPADDR_SYSTEM;
switch (optname) {
case IPV6_PKTINFO:
optdata = (void *)&null_pktinfo;
if (pktopt && pktopt->ip6po_pktinfo) {
bcopy(pktopt->ip6po_pktinfo, &null_pktinfo,
sizeof(null_pktinfo));
in6_clearscope(&null_pktinfo.ipi6_addr);
} else {
/* XXX: we don't have to do this every time... */
bzero(&null_pktinfo, sizeof(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_NEXTHOP:
if (pktopt && pktopt->ip6po_nexthop) {
optdata = (void *)pktopt->ip6po_nexthop;
optdatalen = pktopt->ip6po_nexthop->sa_len;
}
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;
case IPV6_PREFER_TEMPADDR:
if (pktopt)
optdata = (void *)&pktopt->ip6po_prefer_tempaddr;
else
optdata = (void *)&defpreftemp;
optdatalen = sizeof(int);
break;
default: /* should not happen */
#ifdef DIAGNOSTIC
panic("ip6_getpcbopt: unexpected option\n");
#endif
return (ENOPROTOOPT);
}
error = sooptcopyout(sopt, optdata, optdatalen);
return (error);
}
void
ip6_clearpktopts(struct ip6_pktopts *pktopt, int optname)
{
if (pktopt == NULL)
return;
if (optname == -1 || optname == IPV6_PKTINFO) {
if (pktopt->ip6po_pktinfo)
free(pktopt->ip6po_pktinfo, M_IP6OPT);
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_NEXTHOP) {
if (pktopt->ip6po_nextroute.ro_rt) {
RTFREE(pktopt->ip6po_nextroute.ro_rt);
pktopt->ip6po_nextroute.ro_rt = NULL;
}
if (pktopt->ip6po_nexthop)
free(pktopt->ip6po_nexthop, M_IP6OPT);
pktopt->ip6po_nexthop = NULL;
}
if (optname == -1 || optname == IPV6_HOPOPTS) {
if (pktopt->ip6po_hbh)
free(pktopt->ip6po_hbh, M_IP6OPT);
pktopt->ip6po_hbh = NULL;
}
if (optname == -1 || optname == IPV6_RTHDRDSTOPTS) {
if (pktopt->ip6po_dest1)
free(pktopt->ip6po_dest1, M_IP6OPT);
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);
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);
pktopt->ip6po_dest2 = NULL;
}
}
#define PKTOPT_EXTHDRCPY(type) \
do {\
if (src->type) {\
int hlen = (((struct ip6_ext *)src->type)->ip6e_len + 1) << 3;\
dst->type = malloc(hlen, M_IP6OPT, canwait);\
if (dst->type == NULL && canwait == M_NOWAIT)\
goto bad;\
bcopy(src->type, dst->type, hlen);\
}\
} while (/*CONSTCOND*/ 0)
static int
copypktopts(struct ip6_pktopts *dst, struct ip6_pktopts *src, int canwait)
{
if (dst == NULL || src == NULL) {
printf("ip6_clearpktopts: invalid argument\n");
return (EINVAL);
}
dst->ip6po_hlim = src->ip6po_hlim;
dst->ip6po_tclass = src->ip6po_tclass;
dst->ip6po_flags = src->ip6po_flags;
dst->ip6po_minmtu = src->ip6po_minmtu;
dst->ip6po_prefer_tempaddr = src->ip6po_prefer_tempaddr;
if (src->ip6po_pktinfo) {
dst->ip6po_pktinfo = malloc(sizeof(*dst->ip6po_pktinfo),
M_IP6OPT, canwait);
if (dst->ip6po_pktinfo == NULL)
goto bad;
*dst->ip6po_pktinfo = *src->ip6po_pktinfo;
}
if (src->ip6po_nexthop) {
dst->ip6po_nexthop = malloc(src->ip6po_nexthop->sa_len,
M_IP6OPT, canwait);
if (dst->ip6po_nexthop == NULL)
goto bad;
bcopy(src->ip6po_nexthop, dst->ip6po_nexthop,
src->ip6po_nexthop->sa_len);
}
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
struct ip6_pktopts *
ip6_copypktopts(struct ip6_pktopts *src, int canwait)
{
int error;
struct ip6_pktopts *dst;
dst = malloc(sizeof(*dst), M_IP6OPT, canwait);
if (dst == NULL)
return (NULL);
ip6_initpktopts(dst);
if ((error = copypktopts(dst, src, canwait)) != 0) {
free(dst, M_IP6OPT);
return (NULL);
}
return (dst);
}
void
ip6_freepcbopts(struct ip6_pktopts *pktopt)
{
if (pktopt == NULL)
return;
ip6_clearpktopts(pktopt, -1);
free(pktopt, M_IP6OPT);
}
/*
* Set IPv6 outgoing packet options based on advanced API.
*/
int
ip6_setpktopts(struct mbuf *control, struct ip6_pktopts *opt,
struct ip6_pktopts *stickyopt, struct ucred *cred, int uproto)
{
struct cmsghdr *cm = 0;
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, M_NOWAIT)) != 0)
return (error);
}
/*
* XXX: Currently, we assume all the optional information is stored
* in a single mbuf.
*/
if (control->m_next)
return (EINVAL);
for (; control->m_len > 0; control->m_data += CMSG_ALIGN(cm->cmsg_len),
control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
int error;
if (control->m_len < CMSG_LEN(0))
return (EINVAL);
cm = mtod(control, struct cmsghdr *);
if (cm->cmsg_len == 0 || cm->cmsg_len > control->m_len)
return (EINVAL);
if (cm->cmsg_level != IPPROTO_IPV6)
continue;
error = ip6_setpktopt(cm->cmsg_type, CMSG_DATA(cm),
cm->cmsg_len - CMSG_LEN(0), opt, cred, 0, 1, uproto);
if (error)
return (error);
}
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.
* We have 4 cases of combination of "sticky" and "cmsg":
* "sticky=0, cmsg=0": impossible
* "sticky=0, cmsg=1": RFC2292 or RFC3542 ancillary data
* "sticky=1, cmsg=0": RFC3542 socket option
* "sticky=1, cmsg=1": RFC2292 socket option
*/
static int
ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
struct ucred *cred, int sticky, int cmsg, int uproto)
{
int minmtupolicy, preftemp;
int error;
if (!sticky && !cmsg) {
#ifdef DIAGNOSTIC
printf("ip6_setpktopt: impossible case\n");
#endif
return (EINVAL);
}
/*
* IPV6_2292xxx is for backward compatibility to RFC2292, and should
* not be specified in the context of RFC3542. Conversely,
* RFC3542 types should not be specified in the context of RFC2292.
*/
if (!cmsg) {
switch (optname) {
case IPV6_2292PKTINFO:
case IPV6_2292HOPLIMIT:
case IPV6_2292NEXTHOP:
case IPV6_2292HOPOPTS:
case IPV6_2292DSTOPTS:
case IPV6_2292RTHDR:
case IPV6_2292PKTOPTIONS:
return (ENOPROTOOPT);
}
}
if (sticky && cmsg) {
switch (optname) {
case IPV6_PKTINFO:
case IPV6_HOPLIMIT:
case IPV6_NEXTHOP:
case IPV6_HOPOPTS:
case IPV6_DSTOPTS:
case IPV6_RTHDRDSTOPTS:
case IPV6_RTHDR:
case IPV6_USE_MIN_MTU:
case IPV6_DONTFRAG:
case IPV6_TCLASS:
case IPV6_PREFER_TEMPADDR: /* XXX: not an RFC3542 option */
return (ENOPROTOOPT);
}
}
switch (optname) {
case IPV6_2292PKTINFO:
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 (optname == IPV6_PKTINFO && opt->ip6po_pktinfo &&
pktinfo->ipi6_ifindex == 0 &&
IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
ip6_clearpktopts(opt, optname);
break;
}
if (uproto == IPPROTO_TCP && optname == IPV6_PKTINFO &&
sticky && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
return (EINVAL);
}
if (IN6_IS_ADDR_MULTICAST(&pktinfo->ipi6_addr))
return (EINVAL);
/* validate the interface index if specified. */
if (pktinfo->ipi6_ifindex > V_if_index)
return (ENXIO);
if (pktinfo->ipi6_ifindex) {
ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
if (ifp == NULL)
return (ENXIO);
}
if (ifp != NULL && (
ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED))
return (ENETDOWN);
if (ifp != NULL &&
!IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
struct in6_ifaddr *ia;
in6_setscope(&pktinfo->ipi6_addr, ifp, NULL);
ia = in6ifa_ifpwithaddr(ifp, &pktinfo->ipi6_addr);
if (ia == NULL)
return (EADDRNOTAVAIL);
ifa_free(&ia->ia_ifa);
}
/*
* 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_2292HOPLIMIT:
case IPV6_HOPLIMIT:
{
int *hlimp;
/*
* RFC 3542 deprecated the usage of sticky IPV6_HOPLIMIT
* to simplify the ordering among hoplimit options.
*/
if (optname == IPV6_HOPLIMIT && 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_2292NEXTHOP:
case IPV6_NEXTHOP:
if (cred != NULL) {
error = priv_check_cred(cred,
PRIV_NETINET_SETHDROPTS, 0);
if (error)
return (error);
}
if (len == 0) { /* just remove the option */
ip6_clearpktopts(opt, IPV6_NEXTHOP);
break;
}
/* check if cmsg_len is large enough for sa_len */
if (len < sizeof(struct sockaddr) || len < *buf)
return (EINVAL);
switch (((struct sockaddr *)buf)->sa_family) {
case AF_INET6:
{
struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)buf;
int error;
if (sa6->sin6_len != sizeof(struct sockaddr_in6))
return (EINVAL);
if (IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr) ||
IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
return (EINVAL);
}
if ((error = sa6_embedscope(sa6, V_ip6_use_defzone))
!= 0) {
return (error);
}
break;
}
case AF_LINK: /* should eventually be supported */
default:
return (EAFNOSUPPORT);
}
/* turn off the previous option, then set the new option. */
ip6_clearpktopts(opt, IPV6_NEXTHOP);
opt->ip6po_nexthop = malloc(*buf, M_IP6OPT, M_NOWAIT);
if (opt->ip6po_nexthop == NULL)
return (ENOBUFS);
bcopy(buf, opt->ip6po_nexthop, *buf);
break;
case IPV6_2292HOPOPTS:
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 (cred != NULL) {
error = priv_check_cred(cred,
PRIV_NETINET_SETHDROPTS, 0);
if (error)
return (error);
}
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);
bcopy(hbh, opt->ip6po_hbh, hbhlen);
break;
}
case IPV6_2292DSTOPTS:
case IPV6_DSTOPTS:
case IPV6_RTHDRDSTOPTS:
{
struct ip6_dest *dest, **newdest = NULL;
int destlen;
if (cred != NULL) { /* XXX: see the comment for IPV6_HOPOPTS */
error = priv_check_cred(cred,
PRIV_NETINET_SETHDROPTS, 0);
if (error)
return (error);
}
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_2292DSTOPTS:
/*
* The old advacned API is ambiguous on this point.
* Our approach is to determine the position based
* according to the existence of a routing header.
* Note, however, that this depends on the order of the
* extension headers in the ancillary data; the 1st
* part of the destination options header must appear
* before the routing header in the ancillary data,
* too.
* RFC3542 solved the ambiguity by introducing
* separate ancillary data or option types.
*/
if (opt->ip6po_rthdr == NULL)
newdest = &opt->ip6po_dest1;
else
newdest = &opt->ip6po_dest2;
break;
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);
bcopy(dest, *newdest, destlen);
break;
}
case IPV6_2292RTHDR:
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);
bcopy(rth, opt->ip6po_rthdr, 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;
case IPV6_PREFER_TEMPADDR:
if (len != sizeof(int))
return (EINVAL);
preftemp = *(int *)buf;
if (preftemp != IP6PO_TEMPADDR_SYSTEM &&
preftemp != IP6PO_TEMPADDR_NOTPREFER &&
preftemp != IP6PO_TEMPADDR_PREFER) {
return (EINVAL);
}
opt->ip6po_prefer_tempaddr = preftemp;
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. Note that this
* calls the output routine of the loopback "driver", but with an interface
* pointer that might NOT be &loif -- easier than replicating that code here.
*/
void
ip6_mloopback(struct ifnet *ifp, const struct mbuf *m)
{
struct mbuf *copym;
struct ip6_hdr *ip6;
copym = m_copy(m, 0, M_COPYALL);
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 (!M_WRITABLE(copym) ||
copym->m_len < sizeof(struct ip6_hdr)) {
copym = m_pullup(copym, sizeof(struct ip6_hdr));
if (copym == NULL)
return;
}
ip6 = mtod(copym, struct ip6_hdr *);
/*
* clear embedded scope identifiers if necessary.
* in6_clearscope will touch the addresses only when necessary.
*/
in6_clearscope(&ip6->ip6_src);
in6_clearscope(&ip6->ip6_dst);
if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID_IPV6 |
CSUM_PSEUDO_HDR;
copym->m_pkthdr.csum_data = 0xffff;
}
if_simloop(ifp, copym, AF_INET6, 0);
}
/*
* Chop IPv6 header off from the payload.
*/
static 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)) {
mh = m_gethdr(M_NOWAIT, MT_DATA);
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;
}
/*
* Compute IPv6 extension header length.
*/
int
ip6_optlen(struct inpcb *in6p)
{
int len;
if (!in6p->in6p_outputopts)
return 0;
len = 0;
#define elen(x) \
(((struct ip6_ext *)(x)) ? (((struct ip6_ext *)(x))->ip6e_len + 1) << 3 : 0)
len += elen(in6p->in6p_outputopts->ip6po_hbh);
if (in6p->in6p_outputopts->ip6po_rthdr)
/* dest1 is valid with rthdr only */
len += elen(in6p->in6p_outputopts->ip6po_dest1);
len += elen(in6p->in6p_outputopts->ip6po_rthdr);
len += elen(in6p->in6p_outputopts->ip6po_dest2);
return len;
#undef elen
}