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/* $FreeBSD$ */
/* $OpenBSD: ip_ipip.c,v 1.25 2002/06/10 18:04:55 itojun Exp $ */
/*-
* The authors of this code are John Ioannidis (ji@tla.org),
* Angelos D. Keromytis (kermit@csd.uch.gr) and
* Niels Provos (provos@physnet.uni-hamburg.de).
*
* The original version of this code was written by John Ioannidis
* for BSD/OS in Athens, Greece, in November 1995.
*
* Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
* by Angelos D. Keromytis.
*
* Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
* and Niels Provos.
*
* Additional features in 1999 by Angelos D. Keromytis.
*
* Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis,
* Angelos D. Keromytis and Niels Provos.
* Copyright (c) 2001, Angelos D. Keromytis.
*
* Permission to use, copy, and modify this software with or without fee
* is hereby granted, provided that this entire notice is included in
* all copies of any software which is or includes a copy or
* modification of this software.
* You may use this code under the GNU public license if you so wish. Please
* contribute changes back to the authors under this freer than GPL license
* so that we may further the use of strong encryption without limitations to
* all.
*
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
* MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
* PURPOSE.
*/
/*
* IP-inside-IP processing
*/
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_enc.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/kernel.h>
#include <sys/protosw.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/pfil.h>
#include <net/route.h>
#include <net/netisr.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/ip_ecn.h>
#include <netinet/ip_var.h>
#include <netipsec/ipsec.h>
#include <netipsec/xform.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netipsec/ipsec6.h>
#include <netinet6/ip6_ecn.h>
#include <netinet6/in6_var.h>
#include <netinet6/scope6_var.h>
#endif
#include <netipsec/key.h>
#include <netipsec/key_debug.h>
int
ipip_output(struct mbuf *m, struct ipsecrequest *isr, struct mbuf **mp,
int skip, int protoff)
{
struct secasvar *sav;
u_int8_t tp, otos;
struct secasindex *saidx;
int error;
#if defined(INET) || defined(INET6)
u_int8_t itos;
#endif
#ifdef INET
struct ip *ipo;
#endif /* INET */
#ifdef INET6
struct ip6_hdr *ip6, *ip6o;
#endif /* INET6 */
sav = isr->sav;
IPSEC_ASSERT(sav != NULL, ("null SA"));
IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
/* XXX Deal with empty TDB source/destination addresses. */
m_copydata(m, 0, 1, &tp);
tp = (tp >> 4) & 0xff; /* Get the IP version number. */
saidx = &sav->sah->saidx;
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) {
DPRINTF(("%s: unspecified tunnel endpoint "
"address in SA %s/%08lx\n", __func__,
ipsec_address(&saidx->dst),
(u_long) ntohl(sav->spi)));
error = EINVAL;
goto bad;
}
M_PREPEND(m, sizeof(struct ip), M_NOWAIT);
if (m == 0) {
DPRINTF(("%s: M_PREPEND failed\n", __func__));
error = ENOBUFS;
goto bad;
}
ipo = mtod(m, struct ip *);
ipo->ip_v = IPVERSION;
ipo->ip_hl = 5;
ipo->ip_len = htons(m->m_pkthdr.len);
ipo->ip_ttl = V_ip_defttl;
ipo->ip_sum = 0;
ipo->ip_src = saidx->src.sin.sin_addr;
ipo->ip_dst = saidx->dst.sin.sin_addr;
ipo->ip_id = ip_newid();
/* If the inner protocol is IP... */
switch (tp) {
case IPVERSION:
/* Save ECN notification */
m_copydata(m, sizeof(struct ip) +
offsetof(struct ip, ip_tos),
sizeof(u_int8_t), (caddr_t) &itos);
ipo->ip_p = IPPROTO_IPIP;
/*
* We should be keeping tunnel soft-state and
* send back ICMPs if needed.
*/
m_copydata(m, sizeof(struct ip) +
offsetof(struct ip, ip_off),
sizeof(u_int16_t), (caddr_t) &ipo->ip_off);
ipo->ip_off = ntohs(ipo->ip_off);
ipo->ip_off &= ~(IP_DF | IP_MF | IP_OFFMASK);
ipo->ip_off = htons(ipo->ip_off);
break;
#ifdef INET6
case (IPV6_VERSION >> 4):
{
u_int32_t itos32;
/* Save ECN notification. */
m_copydata(m, sizeof(struct ip) +
offsetof(struct ip6_hdr, ip6_flow),
sizeof(u_int32_t), (caddr_t) &itos32);
itos = ntohl(itos32) >> 20;
ipo->ip_p = IPPROTO_IPV6;
ipo->ip_off = 0;
break;
}
#endif /* INET6 */
default:
goto nofamily;
}
otos = 0;
ip_ecn_ingress(ECN_ALLOWED, &otos, &itos);
ipo->ip_tos = otos;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (IN6_IS_ADDR_UNSPECIFIED(&saidx->dst.sin6.sin6_addr) ||
saidx->src.sa.sa_family != AF_INET6 ||
IN6_IS_ADDR_UNSPECIFIED(&saidx->src.sin6.sin6_addr)) {
DPRINTF(("%s: unspecified tunnel endpoint "
"address in SA %s/%08lx\n", __func__,
ipsec_address(&saidx->dst),
(u_long) ntohl(sav->spi)));
error = ENOBUFS;
goto bad;
}
/* scoped address handling */
ip6 = mtod(m, struct ip6_hdr *);
in6_clearscope(&ip6->ip6_src);
in6_clearscope(&ip6->ip6_dst);
M_PREPEND(m, sizeof(struct ip6_hdr), M_NOWAIT);
if (m == 0) {
DPRINTF(("%s: M_PREPEND failed\n", __func__));
error = ENOBUFS;
goto bad;
}
/* Initialize IPv6 header */
ip6o = mtod(m, struct ip6_hdr *);
ip6o->ip6_flow = 0;
ip6o->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6o->ip6_vfc |= IPV6_VERSION;
ip6o->ip6_hlim = IPV6_DEFHLIM;
ip6o->ip6_dst = saidx->dst.sin6.sin6_addr;
ip6o->ip6_src = saidx->src.sin6.sin6_addr;
ip6o->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6));
switch (tp) {
#ifdef INET
case IPVERSION:
/* Save ECN notification */
m_copydata(m, sizeof(struct ip6_hdr) +
offsetof(struct ip, ip_tos), sizeof(u_int8_t),
(caddr_t) &itos);
/* This is really IPVERSION. */
ip6o->ip6_nxt = IPPROTO_IPIP;
break;
#endif /* INET */
case (IPV6_VERSION >> 4):
{
u_int32_t itos32;
/* Save ECN notification. */
m_copydata(m, sizeof(struct ip6_hdr) +
offsetof(struct ip6_hdr, ip6_flow),
sizeof(u_int32_t), (caddr_t) &itos32);
itos = ntohl(itos32) >> 20;
ip6o->ip6_nxt = IPPROTO_IPV6;
break;
}
default:
goto nofamily;
}
otos = 0;
ip_ecn_ingress(V_ip6_ipsec_ecn, &otos, &itos);
ip6o->ip6_flow |= htonl((u_int32_t) otos << 20);
break;
#endif /* INET6 */
default:
nofamily:
DPRINTF(("%s: unsupported protocol family %u\n", __func__,
saidx->dst.sa.sa_family));
error = EAFNOSUPPORT; /* XXX diffs from openbsd */
goto bad;
}
*mp = m;
return (0);
bad:
if (m)
m_freem(m);
*mp = NULL;
return (error);
}
static int
ipe4_init(struct secasvar *sav, struct xformsw *xsp)
{
sav->tdb_xform = xsp;
return 0;
}
static int
ipe4_zeroize(struct secasvar *sav)
{
sav->tdb_xform = NULL;
return 0;
}
static int
ipe4_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
{
/* This is a rather serious mistake, so no conditional printing. */
printf("%s: should never be called\n", __func__);
if (m)
m_freem(m);
return EOPNOTSUPP;
}
static struct xformsw ipe4_xformsw = {
XF_IP4, 0, "IPv4 Simple Encapsulation",
ipe4_init, ipe4_zeroize, ipe4_input, ipip_output,
};
static void
ipe4_attach(void)
{
xform_register(&ipe4_xformsw);
}
SYSINIT(ipe4_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ipe4_attach, NULL);
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