freebsd-nq/sys/netinet6/ip6_output.c
Randall Stewart 1966e5b5a1 The proper fix for the delayed SCTP checksum is to
have the delayed function take an argument as to the offset
to the SCTP header. This allows it to work for V4 and V6.
This of course means changing all callers of the function
to either pass the header len, if they have it, or create
it (ip_hl << 2 or sizeof(ip6_hdr)).
PR:		144529
MFC after:	2 weeks
2010-03-12 22:58:52 +00:00

2926 lines
72 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_ipsec.h"
#include "opt_sctp.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 <net/if.h>
#include <net/netisr.h>
#include <net/route.h>
#include <net/pfil.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_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>
#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>
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 __P((int, u_char *, int, struct ip6_pktopts **,
struct ucred *, int));
static int ip6_pcbopts __P((struct ip6_pktopts **, struct mbuf *,
struct socket *, struct sockopt *));
static int ip6_getpcbopt(struct ip6_pktopts *, int, struct sockopt *);
static int ip6_setpktopt __P((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 __P((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 __P((struct route_in6 *, struct route_in6 *,
struct ifnet *, struct in6_addr *, u_long *, 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)
/*
* 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_rmx.rmx_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_rmx.rmx_mtu.
*
* ifpp - XXX: just for statistics
*/
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, *mhip6;
struct ifnet *ifp, *origifp;
struct mbuf *m = m0;
struct mbuf *mprev = NULL;
int hlen, tlen, len, off;
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 needipsec = 0;
#ifdef SCTP
int sw_csum;
#endif
#ifdef IPSEC
struct ipsec_output_state state;
struct ip6_rthdr *rh = NULL;
int needipsectun = 0;
int segleft_org = 0;
struct secpolicy *sp = NULL;
#endif /* IPSEC */
ip6 = mtod(m, struct ip6_hdr *);
if (ip6 == NULL) {
printf ("ip6 is NULL");
goto bad;
}
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);
}
/*
* IPSec checking which handles several cases.
* FAST IPSEC: We re-injected the packet.
*/
#ifdef IPSEC
switch(ip6_ipsec_output(&m, inp, &flags, &error, &ifp, &sp))
{
case 1: /* Bad packet */
goto freehdrs;
case -1: /* Do IPSec */
needipsec = 1;
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. 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 ((needipsec || 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);
#ifdef IPSEC
if (!needipsec)
goto skip_ipsec2;
/*
* pointers after IPsec headers are not valid any more.
* other pointers need a great care too.
* (IPsec routines should not mangle mbufs prior to AH/ESP)
*/
exthdrs.ip6e_dest2 = NULL;
if (exthdrs.ip6e_rthdr) {
rh = mtod(exthdrs.ip6e_rthdr, struct ip6_rthdr *);
segleft_org = rh->ip6r_segleft;
rh->ip6r_segleft = 0;
}
bzero(&state, sizeof(state));
state.m = m;
error = ipsec6_output_trans(&state, nexthdrp, mprev, sp, flags,
&needipsectun);
m = state.m;
if (error == EJUSTRETURN) {
/*
* We had a SP with a level of 'use' and no SA. We
* will just continue to process the packet without
* IPsec processing.
*/
;
} else if (error) {
/* mbuf is already reclaimed in ipsec6_output_trans. */
m = NULL;
switch (error) {
case EHOSTUNREACH:
case ENETUNREACH:
case EMSGSIZE:
case ENOBUFS:
case ENOMEM:
break;
default:
printf("[%s:%d] (ipsec): error code %d\n",
__func__, __LINE__, error);
/* FALLTHROUGH */
case ENOENT:
/* don't show these error codes to the user */
error = 0;
break;
}
goto bad;
} else if (!needipsectun) {
/*
* In the FAST IPSec case we have already
* re-injected the packet and it has been freed
* by the ipsec_done() function. So, just clean
* up after ourselves.
*/
m = NULL;
goto done;
}
if (exthdrs.ip6e_rthdr) {
/* ah6_output doesn't modify mbuf chain */
rh->ip6r_segleft = segleft_org;
}
skip_ipsec2:;
#endif /* IPSEC */
/*
* 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;
V_ip6stat.ip6s_badscope++;
goto bad;
}
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) {
error = EOPNOTSUPP;
V_ip6stat.ip6s_badscope++;
goto bad;
}
V_ip6stat.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;
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;
}
#ifdef IPSEC
/*
* We may re-inject packets into the stack here.
*/
if (needipsec && needipsectun) {
struct ipsec_output_state state;
/*
* All the extension headers will become inaccessible
* (since they can be encrypted).
* Don't panic, we need no more updates to extension headers
* on inner IPv6 packet (since they are now encapsulated).
*
* IPv6 [ESP|AH] IPv6 [extension headers] payload
*/
bzero(&exthdrs, sizeof(exthdrs));
exthdrs.ip6e_ip6 = m;
bzero(&state, sizeof(state));
state.m = m;
state.ro = (struct route *)ro;
state.dst = (struct sockaddr *)dst;
error = ipsec6_output_tunnel(&state, sp, flags);
m = state.m;
ro = (struct route_in6 *)state.ro;
dst = (struct sockaddr_in6 *)state.dst;
if (error == EJUSTRETURN) {
/*
* We had a SP with a level of 'use' and no SA. We
* will just continue to process the packet without
* IPsec processing.
*/
;
} else if (error) {
/* mbuf is already reclaimed in ipsec6_output_tunnel. */
m0 = m = NULL;
m = NULL;
switch (error) {
case EHOSTUNREACH:
case ENETUNREACH:
case EMSGSIZE:
case ENOBUFS:
case ENOMEM:
break;
default:
printf("[%s:%d] (ipsec): error code %d\n",
__func__, __LINE__, error);
/* FALLTHROUGH */
case ENOENT:
/* don't show these error codes to the user */
error = 0;
break;
}
goto bad;
} else {
/*
* In the FAST IPSec case we have already
* re-injected the packet and it has been freed
* by the ipsec_done() function. So, just clean
* up after ourselves.
*/
m = NULL;
goto done;
}
exthdrs.ip6e_ip6 = m;
}
#endif /* IPSEC */
/* adjust pointer */
ip6 = mtod(m, struct ip6_hdr *);
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 ((error = in6_selectroute(&dst_sa, opt, im6o, ro,
&ifp, &rt)) != 0) {
switch (error) {
case EHOSTUNREACH:
V_ip6stat.ip6s_noroute++;
break;
case EADDRNOTAVAIL:
default:
break; /* XXX statistics? */
}
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);
rt->rt_use++;
}
/*
* 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:
V_ip6stat.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)) {
V_ip6stat.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, dst);
} 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 is not always the case, since
* some versions of MGETHDR() does not
* initialize the field.
*/
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)) != 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 continuous");
#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
* continuous 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 *);
/* 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_localaddr(&ip6->ip6_dst)) {
if (m->m_pkthdr.rcvif == NULL)
m->m_pkthdr.rcvif = V_loif;
if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
m->m_pkthdr.csum_flags |=
CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
m->m_pkthdr.csum_data = 0xffff;
}
m->m_pkthdr.csum_flags |=
CSUM_IP_CHECKED | CSUM_IP_VALID;
#ifdef SCTP
if (m->m_pkthdr.csum_flags & CSUM_SCTP)
m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
#endif
error = netisr_queue(NETISR_IPV6, m);
goto done;
} else
goto again; /* Redo the routing table lookup. */
}
/* XXX: IPFIREWALL_FORWARD */
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
*/
#ifdef SCTP
sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist;
if (sw_csum & CSUM_SCTP) {
sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
sw_csum &= ~CSUM_SCTP;
}
#endif
tlen = m->m_pkthdr.len;
if (opt && (opt->ip6po_flags & IP6PO_DONTFRAG))
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)) { /* 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 as
* well as returning an error code (the latter is not described
* in the API spec.)
*/
u_int32_t mtu32;
struct ip6ctlparam ip6cp;
mtu32 = (u_int32_t)mtu;
bzero(&ip6cp, sizeof(ip6cp));
ip6cp.ip6c_cmdarg = (void *)&mtu32;
pfctlinput2(PRC_MSGSIZE, (struct sockaddr *)&ro_pmtu->ro_dst,
(void *)&ip6cp);
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. */
ia6->ia_ifa.if_opackets++;
ia6->ia_ifa.if_obytes += m->m_pkthdr.len;
ifa_free(&ia6->ia_ifa);
}
error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
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 {
struct mbuf **mnext, *m_frgpart;
struct ip6_frag *ip6f;
u_int32_t id = htonl(ip6_randomid());
u_char nextproto;
int qslots = ifp->if_snd.ifq_maxlen - ifp->if_snd.ifq_len;
/*
* 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;
}
/*
* Verify that we have any chance at all of being able to queue
* the packet or packet fragments
*/
if (qslots <= 0 || ((u_int)qslots * (mtu - hlen)
< tlen /* - hlen */)) {
error = ENOBUFS;
V_ip6stat.ip6s_odropped++;
goto bad;
}
mnext = &m->m_nextpkt;
/*
* 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;
for (off = hlen; off < tlen; off += len) {
MGETHDR(m, M_DONTWAIT, MT_HEADER);
if (!m) {
error = ENOBUFS;
V_ip6stat.ip6s_odropped++;
goto sendorfree;
}
m->m_pkthdr.rcvif = NULL;
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) {
V_ip6stat.ip6s_odropped++;
goto sendorfree;
}
ip6f->ip6f_offlg = htons((u_short)((off - hlen) & ~7));
if (off + len >= tlen)
len = tlen - off;
else
ip6f->ip6f_offlg |= IP6F_MORE_FRAG;
mhip6->ip6_plen = htons((u_short)(len + hlen +
sizeof(*ip6f) - sizeof(struct ip6_hdr)));
if ((m_frgpart = m_copy(m0, off, len)) == 0) {
error = ENOBUFS;
V_ip6stat.ip6s_odropped++;
goto sendorfree;
}
m_cat(m, m_frgpart);
m->m_pkthdr.len = len + hlen + sizeof(*ip6f);
m->m_pkthdr.rcvif = NULL;
ip6f->ip6f_reserved = 0;
ip6f->ip6f_ident = id;
ip6f->ip6f_nxt = nextproto;
V_ip6stat.ip6s_ofragments++;
in6_ifstat_inc(ifp, ifs6_out_fragcreat);
}
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) {
ia->ia_ifa.if_opackets++;
ia->ia_ifa.if_obytes += m->m_pkthdr.len;
}
error = nd6_output(ifp, origifp, m, dst, ro->ro_rt);
} else
m_freem(m);
}
if (error == 0)
V_ip6stat.ip6s_fragmented++;
done:
if (ro == &ip6route && ro->ro_rt) { /* brace necessary for RTFREE */
RTFREE(ro->ro_rt);
} else if (ro_pmtu == &ip6route && ro_pmtu->ro_rt) {
RTFREE(ro_pmtu->ro_rt);
}
#ifdef IPSEC
if (sp != NULL)
KEY_FREESP(&sp);
#endif
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 */
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)
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) {
MGET(mopt, M_DONTWAIT, MT_DATA);
if (mopt == 0)
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.
*/
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;
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_DONTWAIT);
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 ((mlast->m_flags & M_EXT) == 0 &&
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;
MGET(mfrg, M_DONTWAIT, MT_DATA);
if (mfrg == 0)
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_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;
rtalloc((struct route *)ro_pmtu);
}
}
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_rmx.rmx_mtu);
else
mtu = ro_pmtu->ro_rt->rt_rmx.rmx_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 (mtu > ifmtu) {
/*
* 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 = ifmtu;
ro_pmtu->ro_rt->rt_rmx.rmx_mtu = mtu;
}
} 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;
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) {
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_FAITH:
case IPV6_RECVPKTINFO:
case IPV6_RECVHOPLIMIT:
case IPV6_RECVRTHDR:
case IPV6_RECVPATHMTU:
case IPV6_RECVTCLASS:
case IPV6_V6ONLY:
case IPV6_AUTOFLOWLABEL:
case IPV6_BINDANY:
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 { \
if (optval) \
in6p->inp_flags |= (bit); \
else \
in6p->inp_flags &= ~(bit); \
} while (/*CONSTCOND*/ 0)
#define OPTSET2292(bit) \
do { \
in6p->inp_flags |= IN6P_RFC2292; \
if (optval) \
in6p->inp_flags |= (bit); \
else \
in6p->inp_flags &= ~(bit); \
} while (/*CONSTCOND*/ 0)
#define OPTBIT(bit) (in6p->inp_flags & (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_FAITH:
OPTSET(INP_FAITH);
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 (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;
}
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;
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;
}
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_FAITH:
case IPV6_V6ONLY:
case IPV6_PORTRANGE:
case IPV6_RECVTCLASS:
case IPV6_AUTOFLOWLABEL:
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_FAITH:
optval = OPTBIT(INP_FAITH);
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;
}
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);
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;
}
} else { /* level != IPPROTO_IPV6 */
error = EINVAL;
}
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:
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_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;
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);
}
/* validate the interface index if specified. */
if (pktinfo->ipi6_ifindex > V_if_index ||
pktinfo->ipi6_ifindex < 0) {
return (ENXIO);
}
if (pktinfo->ipi6_ifindex) {
ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
if (ifp == NULL)
return (ENXIO);
}
/*
* 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, struct mbuf *m, struct sockaddr_in6 *dst)
{
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 ((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 *);
/*
* 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);
(void)if_simloop(ifp, copym, dst->sin6_family, 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)) {
MGETHDR(mh, M_DONTWAIT, MT_HEADER);
if (mh == 0) {
m_freem(m);
return ENOBUFS;
}
M_MOVE_PKTHDR(mh, m);
MH_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
}