#include <machine/rtems-bsd-kernel-space.h>
/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting
* Copyright (c) 2016 Andrey V. Elsukov <ae@FreeBSD.org>
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
/*
* IPsec output processing.
*/
#include <rtems/bsd/local/opt_inet.h>
#include <rtems/bsd/local/opt_inet6.h>
#include <rtems/bsd/local/opt_ipsec.h>
#include <rtems/bsd/local/opt_sctp.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/hhook.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/if_enc.h>
#include <net/if_var.h>
#include <net/vnet.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>
#include <netinet6/scope6_var.h>
#endif
#include <netinet/in_pcb.h>
#ifdef INET6
#include <netinet/icmp6.h>
#endif
#ifdef SCTP
#include <netinet/sctp_crc32.h>
#endif
#include <netinet/udp.h>
#include <netipsec/ah.h>
#include <netipsec/esp.h>
#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 <machine/in_cksum.h>
#define IPSEC_OSTAT_INC(proto, name) do { \
if ((proto) == IPPROTO_ESP) \
ESPSTAT_INC(esps_##name); \
else if ((proto) == IPPROTO_AH)\
AHSTAT_INC(ahs_##name); \
else \
IPCOMPSTAT_INC(ipcomps_##name); \
} while (0)
static int ipsec_encap(struct mbuf **mp, struct secasindex *saidx);
#ifdef INET
static struct secasvar *
ipsec4_allocsa(struct mbuf *m, struct secpolicy *sp, u_int *pidx, int *error)
{
struct secasindex *saidx, tmpsaidx;
struct ipsecrequest *isr;
struct sockaddr_in *sin;
struct secasvar *sav;
struct ip *ip;
/*
* Check system global policy controls.
*/
next:
isr = sp->req[*pidx];
if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) ||
(isr->saidx.proto == IPPROTO_AH && !V_ah_enable) ||
(isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
DPRINTF(("%s: IPsec outbound packet dropped due"
" to policy (check your sysctls)\n", __func__));
IPSEC_OSTAT_INC(isr->saidx.proto, pdrops);
*error = EHOSTUNREACH;
return (NULL);
}
/*
* Craft SA index to search for proper SA. Note that
* we only initialize unspecified SA peers for transport
* mode; for tunnel mode they must already be filled in.
*/
if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
saidx = &tmpsaidx;
*saidx = isr->saidx;
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
saidx = &sp->req[*pidx]->saidx;
/*
* Lookup SA and validate it.
*/
sav = key_allocsa_policy(sp, saidx, error);
if (sav == NULL) {
IPSECSTAT_INC(ips_out_nosa);
if (*error != 0)
return (NULL);
if (ipsec_get_reqlevel(sp, *pidx) != IPSEC_LEVEL_REQUIRE) {
/*
* We have no SA and policy that doesn't require
* this IPsec transform, thus we can continue w/o
* IPsec processing, i.e. return EJUSTRETURN.
* But first check if there is some bundled transform.
*/
if (sp->tcount > ++(*pidx))
goto next;
*error = EJUSTRETURN;
}
return (NULL);
}
IPSEC_ASSERT(sav->tdb_xform != NULL, ("SA with NULL tdb_xform"));
return (sav);
}
/*
* IPsec output logic for IPv4.
*/
static int
ipsec4_perform_request(struct mbuf *m, struct secpolicy *sp,
struct inpcb *inp, u_int idx)
{
struct ipsec_ctx_data ctx;
union sockaddr_union *dst;
struct secasvar *sav;
struct ip *ip;
int error, i, off;
IPSEC_ASSERT(idx < sp->tcount, ("Wrong IPsec request index %d", idx));
/*
* We hold the reference to SP. Content of SP couldn't be changed.
* Craft secasindex and do lookup for suitable SA.
* Then do encapsulation if needed and call xform's output.
* We need to store SP in the xform callback parameters.
* In xform callback we will extract SP and it can be used to
* determine next transform. At the end of transform we can
* release reference to SP.
*/
sav = ipsec4_allocsa(m, sp, &idx, &error);
if (sav == NULL) {
if (error == EJUSTRETURN) { /* No IPsec required */
key_freesp(&sp);
return (error);
}
goto bad;
}
/*
* XXXAE: most likely ip_sum at this point is wrong.
*/
IPSEC_INIT_CTX(&ctx, &m, inp, sav, AF_INET, IPSEC_ENC_BEFORE);
if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_OUT)) != 0)
goto bad;
ip = mtod(m, struct ip *);
dst = &sav->sah->saidx.dst;
/* Do the appropriate encapsulation, if necessary */
if (sp->req[idx]->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
dst->sa.sa_family != AF_INET || /* PF mismatch */
(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)) {
/* Fix IPv4 header checksum and length */
ip->ip_len = htons(m->m_pkthdr.len);
ip->ip_sum = 0;
ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
error = ipsec_encap(&m, &sav->sah->saidx);
if (error != 0) {
DPRINTF(("%s: encapsulation for SPI 0x%08x failed "
"with error %d\n", __func__, ntohl(sav->spi),
error));
/* XXXAE: IPSEC_OSTAT_INC(tunnel); */
goto bad;
}
inp = NULL;
}
IPSEC_INIT_CTX(&ctx, &m, inp, sav, dst->sa.sa_family, IPSEC_ENC_AFTER);
if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_OUT)) != 0)
goto bad;
/*
* Dispatch to the appropriate IPsec transform logic. The
* packet will be returned for transmission after crypto
* processing, etc. are completed.
*
* NB: m & sav are ``passed to caller'' who's responsible for
* reclaiming their resources.
*/
switch(dst->sa.sa_family) {
case AF_INET:
ip = mtod(m, struct ip *);
i = ip->ip_hl << 2;
off = offsetof(struct ip, ip_p);
break;
#ifdef INET6
case AF_INET6:
i = sizeof(struct ip6_hdr);
off = offsetof(struct ip6_hdr, ip6_nxt);
break;
#endif /* INET6 */
default:
DPRINTF(("%s: unsupported protocol family %u\n",
__func__, dst->sa.sa_family));
error = EPFNOSUPPORT;
IPSEC_OSTAT_INC(sav->sah->saidx.proto, nopf);
goto bad;
}
error = (*sav->tdb_xform->xf_output)(m, sp, sav, idx, i, off);
return (error);
bad:
IPSECSTAT_INC(ips_out_inval);
if (m != NULL)
m_freem(m);
if (sav != NULL)
key_freesav(&sav);
key_freesp(&sp);
return (error);
}
int
ipsec4_process_packet(struct mbuf *m, struct secpolicy *sp,
struct inpcb *inp)
{
return (ipsec4_perform_request(m, sp, inp, 0));
}
static int
ipsec4_common_output(struct mbuf *m, struct inpcb *inp, int forwarding)
{
struct secpolicy *sp;
int error;
/* Lookup for the corresponding outbound security policy */
sp = ipsec4_checkpolicy(m, inp, &error, !forwarding);
if (sp == NULL) {
if (error == -EINVAL) {
/* Discarded by policy. */
m_freem(m);
return (EACCES);
}
return (0); /* No IPsec required. */
}
/*
* Usually we have to have tunnel mode IPsec security policy
* when we are forwarding a packet. Otherwise we could not handle
* encrypted replies, because they are not destined for us. But
* some users are doing source address translation for forwarded
* packets, and thus, even if they are forwarded, the replies will
* return back to us.
*/
if (!forwarding) {
/*
* Do delayed checksums now because we send before
* this is done in the normal processing path.
*/
if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
in_delayed_cksum(m);
m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
}
#ifdef SCTP
if (m->m_pkthdr.csum_flags & CSUM_SCTP) {
struct ip *ip = mtod(m, struct ip *);
sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
}
#endif
}
/* NB: callee frees mbuf and releases reference to SP */
error = ipsec4_process_packet(m, sp, inp);
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 and return without error.
*/
return (0);
}
if (error == 0)
return (EINPROGRESS); /* consumed by IPsec */
return (error);
}
/*
* IPSEC_OUTPUT() method implementation for IPv4.
* 0 - no IPsec handling needed
* other values - mbuf consumed by IPsec.
*/
int
ipsec4_output(struct mbuf *m, struct inpcb *inp)
{
/*
* If the packet is resubmitted to ip_output (e.g. after
* AH, ESP, etc. processing), there will be a tag to bypass
* the lookup and related policy checking.
*/
if (m_tag_find(m, PACKET_TAG_IPSEC_OUT_DONE, NULL) != NULL)
return (0);
return (ipsec4_common_output(m, inp, 0));
}
/*
* IPSEC_FORWARD() method implementation for IPv4.
* 0 - no IPsec handling needed
* other values - mbuf consumed by IPsec.
*/
int
ipsec4_forward(struct mbuf *m)
{
/*
* Check if this packet has an active inbound SP and needs to be
* dropped instead of forwarded.
*/
if (ipsec4_in_reject(m, NULL) != 0) {
m_freem(m);
return (EACCES);
}
return (ipsec4_common_output(m, NULL, 1));
}
#endif
#ifdef INET6
static int
in6_sa_equal_addrwithscope(const struct sockaddr_in6 *sa,
const struct in6_addr *ia)
{
struct in6_addr ia2;
if (IN6_IS_SCOPE_LINKLOCAL(&sa->sin6_addr)) {
memcpy(&ia2, &sa->sin6_addr, sizeof(ia2));
ia2.s6_addr16[1] = htons(sa->sin6_scope_id);
return (IN6_ARE_ADDR_EQUAL(ia, &ia2));
}
return (IN6_ARE_ADDR_EQUAL(&sa->sin6_addr, ia));
}
static struct secasvar *
ipsec6_allocsa(struct mbuf *m, struct secpolicy *sp, u_int *pidx, int *error)
{
struct secasindex *saidx, tmpsaidx;
struct ipsecrequest *isr;
struct sockaddr_in6 *sin6;
struct secasvar *sav;
struct ip6_hdr *ip6;
/*
* Check system global policy controls.
*/
next:
isr = sp->req[*pidx];
if ((isr->saidx.proto == IPPROTO_ESP && !V_esp_enable) ||
(isr->saidx.proto == IPPROTO_AH && !V_ah_enable) ||
(isr->saidx.proto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
DPRINTF(("%s: IPsec outbound packet dropped due"
" to policy (check your sysctls)\n", __func__));
IPSEC_OSTAT_INC(isr->saidx.proto, pdrops);
*error = EHOSTUNREACH;
return (NULL);
}
/*
* 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.
*/
if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) {
saidx = &tmpsaidx;
*saidx = isr->saidx;
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]);
}
}
} else
saidx = &sp->req[*pidx]->saidx;
/*
* Lookup SA and validate it.
*/
sav = key_allocsa_policy(sp, saidx, error);
if (sav == NULL) {
IPSEC6STAT_INC(ips_out_nosa);
if (*error != 0)
return (NULL);
if (ipsec_get_reqlevel(sp, *pidx) != IPSEC_LEVEL_REQUIRE) {
/*
* We have no SA and policy that doesn't require
* this IPsec transform, thus we can continue w/o
* IPsec processing, i.e. return EJUSTRETURN.
* But first check if there is some bundled transform.
*/
if (sp->tcount > ++(*pidx))
goto next;
*error = EJUSTRETURN;
}
return (NULL);
}
IPSEC_ASSERT(sav->tdb_xform != NULL, ("SA with NULL tdb_xform"));
return (sav);
}
/*
* IPsec output logic for IPv6.
*/
static int
ipsec6_perform_request(struct mbuf *m, struct secpolicy *sp,
struct inpcb *inp, u_int idx)
{
struct ipsec_ctx_data ctx;
union sockaddr_union *dst;
struct secasvar *sav;
struct ip6_hdr *ip6;
int error, i, off;
IPSEC_ASSERT(idx < sp->tcount, ("Wrong IPsec request index %d", idx));
sav = ipsec6_allocsa(m, sp, &idx, &error);
if (sav == NULL) {
if (error == EJUSTRETURN) { /* No IPsec required */
key_freesp(&sp);
return (error);
}
goto bad;
}
/* Fix IP length in case if it is not set yet. */
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6));
IPSEC_INIT_CTX(&ctx, &m, inp, sav, AF_INET6, IPSEC_ENC_BEFORE);
if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_OUT)) != 0)
goto bad;
ip6 = mtod(m, struct ip6_hdr *); /* pfil can change mbuf */
dst = &sav->sah->saidx.dst;
/* Do the appropriate encapsulation, if necessary */
if (sp->req[idx]->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */
dst->sa.sa_family != AF_INET6 || /* PF mismatch */
((dst->sa.sa_family == AF_INET6) &&
(!IN6_IS_ADDR_UNSPECIFIED(&dst->sin6.sin6_addr)) &&
(!in6_sa_equal_addrwithscope(&dst->sin6, &ip6->ip6_dst)))) {
if (m->m_pkthdr.len - sizeof(*ip6) > IPV6_MAXPACKET) {
/* No jumbogram support. */
error = ENXIO; /*XXX*/
goto bad;
}
error = ipsec_encap(&m, &sav->sah->saidx);
if (error != 0) {
DPRINTF(("%s: encapsulation for SPI 0x%08x failed "
"with error %d\n", __func__, ntohl(sav->spi),
error));
/* XXXAE: IPSEC_OSTAT_INC(tunnel); */
goto bad;
}
inp = NULL;
}
IPSEC_INIT_CTX(&ctx, &m, inp, sav, dst->sa.sa_family, IPSEC_ENC_AFTER);
if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_OUT)) != 0)
goto bad;
switch(dst->sa.sa_family) {
#ifdef INET
case AF_INET:
{
struct ip *ip;
ip = mtod(m, struct ip *);
i = ip->ip_hl << 2;
off = offsetof(struct ip, ip_p);
}
break;
#endif /* AF_INET */
case AF_INET6:
i = sizeof(struct ip6_hdr);
off = offsetof(struct ip6_hdr, ip6_nxt);
break;
default:
DPRINTF(("%s: unsupported protocol family %u\n",
__func__, dst->sa.sa_family));
error = EPFNOSUPPORT;
IPSEC_OSTAT_INC(sav->sah->saidx.proto, nopf);
goto bad;
}
error = (*sav->tdb_xform->xf_output)(m, sp, sav, idx, i, off);
return (error);
bad:
IPSEC6STAT_INC(ips_out_inval);
if (m != NULL)
m_freem(m);
if (sav != NULL)
key_freesav(&sav);
key_freesp(&sp);
return (error);
}
int
ipsec6_process_packet(struct mbuf *m, struct secpolicy *sp,
struct inpcb *inp)
{
return (ipsec6_perform_request(m, sp, inp, 0));
}
static int
ipsec6_common_output(struct mbuf *m, struct inpcb *inp, int forwarding)
{
struct secpolicy *sp;
int error;
/* Lookup for the corresponding outbound security policy */
sp = ipsec6_checkpolicy(m, inp, &error, !forwarding);
if (sp == NULL) {
if (error == -EINVAL) {
/* Discarded by policy. */
m_freem(m);
return (EACCES);
}
return (0); /* No IPsec required. */
}
if (!forwarding) {
/*
* Do delayed checksums now because we send before
* this is done in the normal processing path.
*/
if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6) {
in6_delayed_cksum(m, m->m_pkthdr.len -
sizeof(struct ip6_hdr), sizeof(struct ip6_hdr));
m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
}
#ifdef SCTP
if (m->m_pkthdr.csum_flags & CSUM_SCTP_IPV6) {
sctp_delayed_cksum(m, sizeof(struct ip6_hdr));
m->m_pkthdr.csum_flags &= ~CSUM_SCTP_IPV6;
}
#endif
}
/* NB: callee frees mbuf and releases reference to SP */
error = ipsec6_process_packet(m, sp, inp);
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 and return without error.
*/
return (0);
}
if (error == 0)
return (EINPROGRESS); /* consumed by IPsec */
return (error);
}
/*
* IPSEC_OUTPUT() method implementation for IPv6.
* 0 - no IPsec handling needed
* other values - mbuf consumed by IPsec.
*/
int
ipsec6_output(struct mbuf *m, struct inpcb *inp)
{
/*
* If the packet is resubmitted to ip_output (e.g. after
* AH, ESP, etc. processing), there will be a tag to bypass
* the lookup and related policy checking.
*/
if (m_tag_find(m, PACKET_TAG_IPSEC_OUT_DONE, NULL) != NULL)
return (0);
return (ipsec6_common_output(m, inp, 0));
}
/*
* IPSEC_FORWARD() method implementation for IPv6.
* 0 - no IPsec handling needed
* other values - mbuf consumed by IPsec.
*/
int
ipsec6_forward(struct mbuf *m)
{
/*
* Check if this packet has an active inbound SP and needs to be
* dropped instead of forwarded.
*/
if (ipsec6_in_reject(m, NULL) != 0) {
m_freem(m);
return (EACCES);
}
return (ipsec6_common_output(m, NULL, 1));
}
#endif /* INET6 */
int
ipsec_process_done(struct mbuf *m, struct secpolicy *sp, struct secasvar *sav,
u_int idx)
{
struct xform_history *xh;
struct secasindex *saidx;
struct m_tag *mtag;
int error;
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(("%s: unknown protocol family %u\n", __func__,
saidx->dst.sa.sa_family));
error = ENXIO;
goto bad;
}
/*
* Add a record of what we've done to the packet.
*/
mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, sizeof(*xh), M_NOWAIT);
if (mtag == NULL) {
DPRINTF(("%s: could not get packet tag\n", __func__));
error = ENOMEM;
goto bad;
}
xh = (struct xform_history *)(mtag + 1);
xh->dst = saidx->dst;
xh->proto = saidx->proto;
xh->mode = saidx->mode;
xh->spi = sav->spi;
m_tag_prepend(m, mtag);
key_sa_recordxfer(sav, m); /* record data transfer */
/*
* 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 (++idx < sp->tcount) {
switch (saidx->dst.sa.sa_family) {
#ifdef INET
case AF_INET:
key_freesav(&sav);
IPSECSTAT_INC(ips_out_bundlesa);
return (ipsec4_perform_request(m, sp, NULL, idx));
/* NOTREACHED */
#endif
#ifdef INET6
case AF_INET6:
key_freesav(&sav);
IPSEC6STAT_INC(ips_out_bundlesa);
return (ipsec6_perform_request(m, sp, NULL, idx));
/* NOTREACHED */
#endif /* INET6 */
default:
DPRINTF(("%s: unknown protocol family %u\n", __func__,
saidx->dst.sa.sa_family));
error = EPFNOSUPPORT;
goto bad;
}
}
key_freesp(&sp), sp = NULL; /* Release reference to SP */
#ifdef INET
/*
* Do UDP encapsulation if SA requires it.
*/
if (sav->natt != NULL) {
error = udp_ipsec_output(m, sav);
if (error != 0)
goto bad;
}
#endif /* INET */
/*
* We're done with IPsec processing, transmit the packet using the
* appropriate network protocol (IP or IPv6).
*/
switch (saidx->dst.sa.sa_family) {
#ifdef INET
case AF_INET:
key_freesav(&sav);
return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL);
#endif /* INET */
#ifdef INET6
case AF_INET6:
key_freesav(&sav);
return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
#endif /* INET6 */
}
panic("ipsec_process_done");
bad:
m_freem(m);
key_freesav(&sav);
if (sp != NULL)
key_freesp(&sp);
return (error);
}
/*
* ipsec_prepend() is optimized version of M_PREPEND().
* ipsec_encap() is called by IPsec output routine for tunnel mode SA.
* It is expected that after IP encapsulation some IPsec transform will
* be performed. Each IPsec transform inserts its variable length header
* just after outer IP header using m_makespace(). If given mbuf has not
* enough free space at the beginning, we allocate new mbuf and reserve
* some space at the beginning and at the end.
* This helps avoid allocating of new mbuf and data copying in m_makespace(),
* we place outer header in the middle of mbuf's data with reserved leading
* and trailing space:
* [ LEADINGSPACE ][ Outer IP header ][ TRAILINGSPACE ]
* LEADINGSPACE will be used to add ethernet header, TRAILINGSPACE will
* be used to inject AH/ESP/IPCOMP header.
*/
#define IPSEC_TRAILINGSPACE (sizeof(struct udphdr) +/* NAT-T */ \
max(sizeof(struct newesp) + EALG_MAX_BLOCK_LEN, /* ESP + IV */ \
sizeof(struct newah) + HASH_MAX_LEN /* AH + ICV */))
static struct mbuf *
ipsec_prepend(struct mbuf *m, int len, int how)
{
struct mbuf *n;
M_ASSERTPKTHDR(m);
IPSEC_ASSERT(len < MHLEN, ("wrong length"));
if (M_LEADINGSPACE(m) >= len) {
/* No need to allocate new mbuf. */
m->m_data -= len;
m->m_len += len;
m->m_pkthdr.len += len;
return (m);
}
n = m_gethdr(how, m->m_type);
if (n == NULL) {
m_freem(m);
return (NULL);
}
m_move_pkthdr(n, m);
n->m_next = m;
if (len + IPSEC_TRAILINGSPACE < M_SIZE(n))
m_align(n, len + IPSEC_TRAILINGSPACE);
n->m_len = len;
n->m_pkthdr.len += len;
return (n);
}
static int
ipsec_encap(struct mbuf **mp, struct secasindex *saidx)
{
#ifdef INET6
struct ip6_hdr *ip6;
#endif
struct ip *ip;
int setdf;
uint8_t itos, proto;
ip = mtod(*mp, struct ip *);
switch (ip->ip_v) {
#ifdef INET
case IPVERSION:
proto = IPPROTO_IPIP;
/*
* Collect IP_DF state from the inner header
* and honor system-wide control of how to handle it.
*/
switch (V_ip4_ipsec_dfbit) {
case 0: /* clear in outer header */
case 1: /* set in outer header */
setdf = V_ip4_ipsec_dfbit;
break;
default:/* propagate to outer header */
setdf = (ip->ip_off & htons(IP_DF)) != 0;
}
itos = ip->ip_tos;
break;
#endif
#ifdef INET6
case (IPV6_VERSION >> 4):
proto = IPPROTO_IPV6;
ip6 = mtod(*mp, struct ip6_hdr *);
itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
setdf = V_ip4_ipsec_dfbit ? 1: 0;
/* scoped address handling */
in6_clearscope(&ip6->ip6_src);
in6_clearscope(&ip6->ip6_dst);
break;
#endif
default:
return (EAFNOSUPPORT);
}
switch (saidx->dst.sa.sa_family) {
#ifdef INET
case AF_INET:
if (saidx->src.sa.sa_family != AF_INET ||
saidx->src.sin.sin_addr.s_addr == INADDR_ANY ||
saidx->dst.sin.sin_addr.s_addr == INADDR_ANY)
return (EINVAL);
*mp = ipsec_prepend(*mp, sizeof(struct ip), M_NOWAIT);
if (*mp == NULL)
return (ENOBUFS);
ip = mtod(*mp, struct ip *);
ip->ip_v = IPVERSION;
ip->ip_hl = sizeof(struct ip) >> 2;
ip->ip_p = proto;
ip->ip_len = htons((*mp)->m_pkthdr.len);
ip->ip_ttl = V_ip_defttl;
ip->ip_sum = 0;
ip->ip_off = setdf ? htons(IP_DF): 0;
ip->ip_src = saidx->src.sin.sin_addr;
ip->ip_dst = saidx->dst.sin.sin_addr;
ip_ecn_ingress(V_ip4_ipsec_ecn, &ip->ip_tos, &itos);
ip_fillid(ip);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (saidx->src.sa.sa_family != AF_INET6 ||
IN6_IS_ADDR_UNSPECIFIED(&saidx->src.sin6.sin6_addr) ||
IN6_IS_ADDR_UNSPECIFIED(&saidx->dst.sin6.sin6_addr))
return (EINVAL);
*mp = ipsec_prepend(*mp, sizeof(struct ip6_hdr), M_NOWAIT);
if (*mp == NULL)
return (ENOBUFS);
ip6 = mtod(*mp, struct ip6_hdr *);
ip6->ip6_flow = 0;
ip6->ip6_vfc = IPV6_VERSION;
ip6->ip6_hlim = V_ip6_defhlim;
ip6->ip6_nxt = proto;
ip6->ip6_dst = saidx->dst.sin6.sin6_addr;
/* For link-local address embed scope zone id */
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst))
ip6->ip6_dst.s6_addr16[1] =
htons(saidx->dst.sin6.sin6_scope_id & 0xffff);
ip6->ip6_src = saidx->src.sin6.sin6_addr;
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src))
ip6->ip6_src.s6_addr16[1] =
htons(saidx->src.sin6.sin6_scope_id & 0xffff);
ip6->ip6_plen = htons((*mp)->m_pkthdr.len - sizeof(*ip6));
ip_ecn_ingress(V_ip6_ipsec_ecn, &proto, &itos);
ip6->ip6_flow |= htonl((uint32_t)proto << 20);
break;
#endif /* INET6 */
default:
return (EAFNOSUPPORT);
}
(*mp)->m_flags &= ~(M_BCAST | M_MCAST);
return (0);
}
