NetBSD/sys/netipsec/ipsec_output.c

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/* $NetBSD: ipsec_output.c,v 1.2 2003/08/15 03:42:07 jonathan Exp $ */
/* $FreeBSD: src/sys/netipsec/ipsec_output.c,v 1.3.2.1 2003/01/24 05:11:35 sam Exp $ */
/* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ipsec_output.c,v 1.2 2003/08/15 03:42:07 jonathan Exp $");
/*
* IPsec output processing.
*/
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/errno.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/in_var.h>
#include <netinet/ip_ecn.h>
#ifdef INET6
#include <netinet6/ip6_ecn.h>
#endif
#include <netinet/ip6.h>
#ifdef INET6
#include <netinet6/ip6_var.h>
#endif
#include <netinet/in_pcb.h>
#ifdef INET6
#include <netinet/icmp6.h>
#endif
#include <netipsec/ipsec.h>
#ifdef INET6
#include <netipsec/ipsec6.h>
#endif
#include <netipsec/ah_var.h>
#include <netipsec/esp_var.h>
#include <netipsec/ipcomp_var.h>
#include <netipsec/xform.h>
#include <netipsec/key.h>
#include <netipsec/keydb.h>
#include <netipsec/key_debug.h>
#include <netipsec/ipsec_osdep.h>
int
ipsec_process_done(struct mbuf *m, struct ipsecrequest *isr)
{
struct tdb_ident *tdbi;
struct m_tag *mtag;
struct secasvar *sav;
struct secasindex *saidx;
int error;
IPSEC_SPLASSERT_SOFTNET("ipsec_process_done");
IPSEC_ASSERT(m != NULL, ("ipsec_process_done: null mbuf"));
IPSEC_ASSERT(isr != NULL, ("ipsec_process_done: null ISR"));
sav = isr->sav;
IPSEC_ASSERT(sav != NULL, ("ipsec_process_done: null SA"));
IPSEC_ASSERT(sav->sah != NULL, ("ipsec_process_done: null SAH"));
saidx = &sav->sah->saidx;
switch (saidx->dst.sa.sa_family) {
#ifdef INET
case AF_INET:
/* Fix the header length, for AH processing. */
mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
/* Fix the header length, for AH processing. */
if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) {
error = ENXIO;
goto bad;
}
if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) {
/* No jumbogram support. */
error = ENXIO; /*?*/
goto bad;
}
mtod(m, struct ip6_hdr *)->ip6_plen =
htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
break;
#endif /* INET6 */
default:
DPRINTF(("ipsec_process_done: unknown protocol family %u\n",
saidx->dst.sa.sa_family));
error = ENXIO;
goto bad;
}
/*
* Add a record of what we've done or what needs to be done to the
* packet.
*/
mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE,
sizeof(struct tdb_ident), M_NOWAIT);
if (mtag == NULL) {
DPRINTF(("ipsec_process_done: could not get packet tag\n"));
error = ENOMEM;
goto bad;
}
tdbi = (struct tdb_ident *)(mtag + 1);
tdbi->dst = saidx->dst;
tdbi->proto = saidx->proto;
tdbi->spi = sav->spi;
m_tag_prepend(m, mtag);
/*
* If there's another (bundled) SA to apply, do so.
* Note that this puts a burden on the kernel stack size.
* If this is a problem we'll need to introduce a queue
* to set the packet on so we can unwind the stack before
* doing further processing.
*/
if (isr->next) {
newipsecstat.ips_out_bundlesa++;
return ipsec4_process_packet(m, isr->next, 0, 0);
}
/*
* We're done with IPsec processing, transmit the packet using the
* appropriate network protocol (IP or IPv6). SPD lookup will be
* performed again there.
*/
switch (saidx->dst.sa.sa_family) {
#ifdef INET
struct ip *ip;
case AF_INET:
ip = mtod(m, struct ip *);
#ifdef __FreeBSD__
/* FreeBSD ip_output() expects ip_len, ip_off in host endian */
ip->ip_len = ntohs(ip->ip_len);
ip->ip_off = ntohs(ip->ip_off);
#endif /* __FreeBSD_ */
return ip_output(m, NULL, NULL, IP_RAWOUTPUT,
(struct ip_moptions *)0, (struct inpcb*)0);
#endif /* INET */
#ifdef INET6
case AF_INET6:
/*
* We don't need massage, IPv6 header fields are always in
* net endian.
*/
return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
#endif /* INET6 */
}
panic("ipsec_process_done");
bad:
m_freem(m);
KEY_FREESAV(&sav);
return (error);
}
static struct ipsecrequest *
ipsec_nextisr(
struct mbuf *m,
struct ipsecrequest *isr,
int af,
struct secasindex *saidx,
int *error
)
{
#define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \
isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++)
struct secasvar *sav;
IPSEC_SPLASSERT_SOFTNET("ipsec_nextisr");
IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
("ipsec_nextisr: invalid address family %u", af));
again:
/*
* Craft SA index to search for proper SA. Note that
* we only fillin unspecified SA peers for transport
* mode; for tunnel mode they must already be filled in.
*/
*saidx = isr->saidx;
if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
/* Fillin unspecified SA peers only for transport mode */
if (af == AF_INET) {
struct sockaddr_in *sin;
struct ip *ip = mtod(m, struct ip *);
if (saidx->src.sa.sa_len == 0) {
sin = &saidx->src.sin;
sin->sin_len = sizeof(*sin);
sin->sin_family = AF_INET;
sin->sin_port = IPSEC_PORT_ANY;
sin->sin_addr = ip->ip_src;
}
if (saidx->dst.sa.sa_len == 0) {
sin = &saidx->dst.sin;
sin->sin_len = sizeof(*sin);
sin->sin_family = AF_INET;
sin->sin_port = IPSEC_PORT_ANY;
sin->sin_addr = ip->ip_dst;
}
} else {
struct sockaddr_in6 *sin6;
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
if (saidx->src.sin6.sin6_len == 0) {
sin6 = (struct sockaddr_in6 *)&saidx->src;
sin6->sin6_len = sizeof(*sin6);
sin6->sin6_family = AF_INET6;
sin6->sin6_port = IPSEC_PORT_ANY;
sin6->sin6_addr = ip6->ip6_src;
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
/* fix scope id for comparing SPD */
sin6->sin6_addr.s6_addr16[1] = 0;
sin6->sin6_scope_id =
ntohs(ip6->ip6_src.s6_addr16[1]);
}
}
if (saidx->dst.sin6.sin6_len == 0) {
sin6 = (struct sockaddr_in6 *)&saidx->dst;
sin6->sin6_len = sizeof(*sin6);
sin6->sin6_family = AF_INET6;
sin6->sin6_port = IPSEC_PORT_ANY;
sin6->sin6_addr = ip6->ip6_dst;
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
/* fix scope id for comparing SPD */
sin6->sin6_addr.s6_addr16[1] = 0;
sin6->sin6_scope_id =
ntohs(ip6->ip6_dst.s6_addr16[1]);
}
}
}
}
/*
* Lookup SA and validate it.
*/
*error = key_checkrequest(isr, saidx);
if (*error != 0) {
/*
* IPsec processing is required, but no SA found.
* I assume that key_acquire() had been called
* to get/establish the SA. Here I discard
* this packet because it is responsibility for
* upper layer to retransmit the packet.
*/
newipsecstat.ips_out_nosa++;
goto bad;
}
sav = isr->sav;
if (sav == NULL) { /* XXX valid return */
IPSEC_ASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE,
("ipsec_nextisr: no SA found, but required; level %u",
ipsec_get_reqlevel(isr)));
isr = isr->next;
if (isr == NULL) {
/*XXXstatistic??*/
*error = EINVAL; /*XXX*/
return isr;
}
goto again;
}
/*
* Check system global policy controls.
*/
if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) ||
(isr->saidx.proto == IPPROTO_AH && !ah_enable) ||
(isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) {
DPRINTF(("ipsec_nextisr: IPsec outbound packet dropped due"
" to policy (check your sysctls)\n"));
IPSEC_OSTAT(espstat.esps_pdrops, ahstat.ahs_pdrops,
ipcompstat.ipcomps_pdrops);
*error = EHOSTUNREACH;
goto bad;
}
/*
* Sanity check the SA contents for the caller
* before they invoke the xform output method.
*/
if (sav->tdb_xform == NULL) {
DPRINTF(("ipsec_nextisr: no transform for SA\n"));
IPSEC_OSTAT(espstat.esps_noxform, ahstat.ahs_noxform,
ipcompstat.ipcomps_noxform);
*error = EHOSTUNREACH;
goto bad;
}
return isr;
bad:
IPSEC_ASSERT(*error != 0, ("ipsec_nextisr: error return w/ no error code"));
return NULL;
#undef IPSEC_OSTAT
}
#ifdef INET
/*
* IPsec output logic for IPv4.
*/
int
ipsec4_process_packet(
struct mbuf *m,
struct ipsecrequest *isr,
int flags,
int tunalready)
{
struct secasindex saidx;
struct secasvar *sav;
struct ip *ip;
int s, error, i, off;
IPSEC_ASSERT(m != NULL, ("ipsec4_process_packet: null mbuf"));
IPSEC_ASSERT(isr != NULL, ("ipsec4_process_packet: null isr"));
s = splsoftnet(); /* insure SA contents don't change */
isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error);
if (isr == NULL)
goto bad;
sav = isr->sav;
if (!tunalready) {
union sockaddr_union *dst = &sav->sah->saidx.dst;
int setdf;
/*
* Collect IP_DF state from the outer header.
*/
if (dst->sa.sa_family == AF_INET) {
if (m->m_len < sizeof (struct ip) &&
(m = m_pullup(m, sizeof (struct ip))) == NULL) {
error = ENOBUFS;
goto bad;
}
ip = mtod(m, struct ip *);
/* Honor system-wide control of how to handle IP_DF */
switch (ip4_ipsec_dfbit) {
case 0: /* clear in outer header */
case 1: /* set in outer header */
setdf = ip4_ipsec_dfbit;
break;
default: /* propagate to outer header */
setdf = ntohs(ip->ip_off & IP_DF);
break;
}
} else {
ip = NULL; /* keep compiler happy */
setdf = 0;
}
/* Do the appropriate encapsulation, if necessary */
if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
dst->sa.sa_family != AF_INET || /* PF mismatch */
#if 0
(sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */
sav->tdb_xform->xf_type == XF_IP4 || /* ditto */
#endif
(dst->sa.sa_family == AF_INET && /* Proxy */
dst->sin.sin_addr.s_addr != INADDR_ANY &&
dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) {
struct mbuf *mp;
/* Fix IPv4 header checksum and length */
if (m->m_len < sizeof (struct ip) &&
(m = m_pullup(m, sizeof (struct ip))) == NULL) {
error = ENOBUFS;
goto bad;
}
ip = mtod(m, struct ip *);
ip->ip_len = htons(m->m_pkthdr.len);
ip->ip_sum = 0;
#ifdef _IP_VHL
if (ip->ip_vhl == IP_VHL_BORING)
ip->ip_sum = in_cksum_hdr(ip);
else
ip->ip_sum = in_cksum(m,
_IP_VHL_HL(ip->ip_vhl) << 2);
#else
ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
#endif
/* Encapsulate the packet */
error = ipip_output(m, isr, &mp, 0, 0);
if (mp == NULL && !error) {
/* Should never happen. */
DPRINTF(("ipsec4_process_packet: ipip_output "
"returns no mbuf and no error!"));
error = EFAULT;
}
if (error) {
if (mp)
m_freem(mp);
goto bad;
}
m = mp, mp = NULL;
/*
* ipip_output clears IP_DF in the new header. If
* we need to propagate IP_DF from the outer header,
* then we have to do it here.
*
* XXX shouldn't assume what ipip_output does.
*/
if (dst->sa.sa_family == AF_INET && setdf) {
if (m->m_len < sizeof (struct ip) &&
(m = m_pullup(m, sizeof (struct ip))) == NULL) {
error = ENOBUFS;
goto bad;
}
ip = mtod(m, struct ip *);
ip->ip_off = ntohs(ip->ip_off);
ip->ip_off |= IP_DF;
ip->ip_off = htons(ip->ip_off);
}
}
}
/*
* Dispatch to the appropriate IPsec transform logic. The
* packet will be returned for transmission after crypto
* processing, etc. are completed. For encapsulation we
* bypass this call because of the explicit call done above
* (necessary to deal with IP_DF handling for IPv4).
*
* NB: m & sav are ``passed to caller'' who's reponsible for
* for reclaiming their resources.
*/
if (sav->tdb_xform->xf_type != XF_IP4) {
ip = mtod(m, struct ip *);
i = ip->ip_hl << 2;
off = offsetof(struct ip, ip_p);
error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off);
} else {
error = ipsec_process_done(m, isr);
}
splx(s);
return error;
bad:
splx(s);
if (m)
m_freem(m);
return error;
}
#endif
#ifdef INET6
/*
* Chop IP6 header from the payload.
*/
static struct mbuf *
ipsec6_splithdr(struct mbuf *m)
{
struct mbuf *mh;
struct ip6_hdr *ip6;
int hlen;
IPSEC_ASSERT(m->m_len >= sizeof (struct ip6_hdr),
("ipsec6_splithdr: first mbuf too short, len %u", m->m_len));
ip6 = mtod(m, struct ip6_hdr *);
hlen = sizeof(struct ip6_hdr);
if (m->m_len > hlen) {
MGETHDR(mh, M_DONTWAIT, MT_HEADER);
if (!mh) {
m_freem(m);
return NULL;
}
M_MOVE_PKTHDR(mh, m);
MH_ALIGN(mh, hlen);
m->m_len -= hlen;
m->m_data += hlen;
mh->m_next = m;
m = mh;
m->m_len = hlen;
bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen);
} else if (m->m_len < hlen) {
m = m_pullup(m, hlen);
if (!m)
return NULL;
}
return m;
}
/*
* IPsec output logic for IPv6, transport mode.
*/
int
ipsec6_output_trans(
struct ipsec_output_state *state,
u_char *nexthdrp,
struct mbuf *mprev,
struct secpolicy *sp,
int flags,
int *tun)
{
struct ipsecrequest *isr;
struct secasindex saidx;
int error = 0;
struct mbuf *m;
IPSEC_ASSERT(state != NULL, ("ipsec6_output: null state"));
IPSEC_ASSERT(state->m != NULL, ("ipsec6_output: null m"));
IPSEC_ASSERT(nexthdrp != NULL, ("ipsec6_output: null nexthdrp"));
IPSEC_ASSERT(mprev != NULL, ("ipsec6_output: null mprev"));
IPSEC_ASSERT(sp != NULL, ("ipsec6_output: null sp"));
IPSEC_ASSERT(tun != NULL, ("ipsec6_output: null tun"));
KEYDEBUG(KEYDEBUG_IPSEC_DATA,
printf("ipsec6_output_trans: applyed SP\n");
kdebug_secpolicy(sp));
isr = sp->req;
if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
/* the rest will be handled by ipsec6_output_tunnel() */
*tun = 1; /* need tunnel-mode processing */
return 0;
}
*tun = 0;
m = state->m;
isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
if (isr == NULL) {
#ifdef notdef
/* XXX should notification be done for all errors ? */
/*
* Notify the fact that the packet is discarded
* to ourselves. I believe this is better than
* just silently discarding. (jinmei@kame.net)
* XXX: should we restrict the error to TCP packets?
* XXX: should we directly notify sockets via
* pfctlinputs?
*/
icmp6_error(m, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_ADMIN, 0);
m = NULL; /* NB: icmp6_error frees mbuf */
#endif
goto bad;
}
return (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
sizeof (struct ip6_hdr),
offsetof(struct ip6_hdr, ip6_nxt));
bad:
if (m)
m_freem(m);
state->m = NULL;
return error;
}
static int
ipsec6_encapsulate(struct mbuf *m, struct secasvar *sav)
{
struct ip6_hdr *oip6;
struct ip6_hdr *ip6;
size_t plen;
/* can't tunnel between different AFs */
if (sav->sah->saidx.src.sa.sa_family != AF_INET6 ||
sav->sah->saidx.dst.sa.sa_family != AF_INET6) {
m_freem(m);
return EINVAL;
}
IPSEC_ASSERT(m->m_len != sizeof (struct ip6_hdr),
("ipsec6_encapsulate: mbuf wrong size; len %u", m->m_len));
/*
* grow the mbuf to accomodate the new IPv6 header.
*/
plen = m->m_pkthdr.len;
if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) {
struct mbuf *n;
MGET(n, M_DONTWAIT, MT_DATA);
if (!n) {
m_freem(m);
return ENOBUFS;
}
n->m_len = sizeof(struct ip6_hdr);
n->m_next = m->m_next;
m->m_next = n;
m->m_pkthdr.len += sizeof(struct ip6_hdr);
oip6 = mtod(n, struct ip6_hdr *);
} else {
m->m_next->m_len += sizeof(struct ip6_hdr);
m->m_next->m_data -= sizeof(struct ip6_hdr);
m->m_pkthdr.len += sizeof(struct ip6_hdr);
oip6 = mtod(m->m_next, struct ip6_hdr *);
}
ip6 = mtod(m, struct ip6_hdr *);
ovbcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr));
/* Fake link-local scope-class addresses */
if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src))
oip6->ip6_src.s6_addr16[1] = 0;
if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst))
oip6->ip6_dst.s6_addr16[1] = 0;
/* construct new IPv6 header. see RFC 2401 5.1.2.2 */
/* ECN consideration. */
ip6_ecn_ingress(ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow);
if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr))
ip6->ip6_plen = htons(plen);
else {
/* ip6->ip6_plen will be updated in ip6_output() */
}
ip6->ip6_nxt = IPPROTO_IPV6;
sav->sah->saidx.src.sin6.sin6_addr = ip6->ip6_src;
sav->sah->saidx.dst.sin6.sin6_addr = ip6->ip6_dst;
ip6->ip6_hlim = IPV6_DEFHLIM;
/* XXX Should ip6_src be updated later ? */
return 0;
}
/*
* IPsec output logic for IPv6, tunnel mode.
*/
int
ipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags)
{
struct ip6_hdr *ip6;
struct ipsecrequest *isr;
struct secasindex saidx;
int error;
struct sockaddr_in6* dst6;
struct mbuf *m;
IPSEC_ASSERT(state != NULL, ("ipsec6_output: null state"));
IPSEC_ASSERT(state->m != NULL, ("ipsec6_output: null m"));
IPSEC_ASSERT(sp != NULL, ("ipsec6_output: null sp"));
KEYDEBUG(KEYDEBUG_IPSEC_DATA,
printf("ipsec6_output_tunnel: applyed SP\n");
kdebug_secpolicy(sp));
m = state->m;
/*
* transport mode ipsec (before the 1st tunnel mode) is already
* processed by ipsec6_output_trans().
*/
for (isr = sp->req; isr; isr = isr->next) {
if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
break;
}
isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error);
if (isr == NULL)
goto bad;
/*
* There may be the case that SA status will be changed when
* we are refering to one. So calling splsoftnet().
*/
if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
/*
* build IPsec tunnel.
*/
/* XXX should be processed with other familiy */
if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) {
ipseclog((LOG_ERR, "ipsec6_output_tunnel: "
"family mismatched between inner and outer, spi=%lu\n",
ntohl(isr->sav->spi)));
newipsecstat.ips_out_inval++;
error = EAFNOSUPPORT;
goto bad;
}
m = ipsec6_splithdr(m);
if (!m) {
newipsecstat.ips_out_nomem++;
error = ENOMEM;
goto bad;
}
error = ipsec6_encapsulate(m, isr->sav);
if (error) {
m = NULL;
goto bad;
}
ip6 = mtod(m, struct ip6_hdr *);
state->ro = &isr->sav->sah->sa_route;
state->dst = (struct sockaddr *)&state->ro->ro_dst;
dst6 = (struct sockaddr_in6 *)state->dst;
if (state->ro->ro_rt
&& ((state->ro->ro_rt->rt_flags & RTF_UP) == 0
|| !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) {
RTFREE(state->ro->ro_rt);
state->ro->ro_rt = NULL;
}
if (state->ro->ro_rt == 0) {
bzero(dst6, sizeof(*dst6));
dst6->sin6_family = AF_INET6;
dst6->sin6_len = sizeof(*dst6);
dst6->sin6_addr = ip6->ip6_dst;
rtalloc(state->ro);
}
if (state->ro->ro_rt == 0) {
ip6stat.ip6s_noroute++;
newipsecstat.ips_out_noroute++;
error = EHOSTUNREACH;
goto bad;
}
/* adjust state->dst if tunnel endpoint is offlink */
if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) {
state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway;
dst6 = (struct sockaddr_in6 *)state->dst;
}
}
m = ipsec6_splithdr(m);
if (!m) {
newipsecstat.ips_out_nomem++;
error = ENOMEM;
goto bad;
}
ip6 = mtod(m, struct ip6_hdr *);
return (*isr->sav->tdb_xform->xf_output)(m, isr, NULL,
sizeof (struct ip6_hdr),
offsetof(struct ip6_hdr, ip6_nxt));
bad:
if (m)
m_freem(m);
state->m = NULL;
return error;
}
#endif /*INET6*/