#include <machine/rtems-bsd-kernel-space.h>
/*-
* SPDX-License-Identifier: BSD-2-Clause-NetBSD
*
* Copyright (c) 1998 The NetBSD Foundation, Inc.
* Copyright (c) 2014, 2018 Andrey V. Elsukov <ae@FreeBSD.org>
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Heiko W.Rupp <hwr@pilhuhn.de>
*
* IPv6-over-GRE contributed by Gert Doering <gert@greenie.muc.de>
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*
* $NetBSD: ip_gre.c,v 1.29 2003/09/05 23:02:43 itojun Exp $
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <rtems/bsd/local/opt_inet.h>
#include <rtems/bsd/local/opt_inet6.h>
#include <sys/param.h>
#include <sys/jail.h>
#include <sys/systm.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/ip_encap.h>
#include <netinet/ip_var.h>
#ifdef INET6
#include <netinet/ip6.h>
#endif
#include <net/if_gre.h>
#define GRE_TTL 30
VNET_DEFINE(int, ip_gre_ttl) = GRE_TTL;
#define V_ip_gre_ttl VNET(ip_gre_ttl)
SYSCTL_INT(_net_inet_ip, OID_AUTO, grettl, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(ip_gre_ttl), 0, "Default TTL value for encapsulated packets");
VNET_DEFINE_STATIC(struct gre_list *, ipv4_hashtbl) = NULL;
VNET_DEFINE_STATIC(struct gre_list *, ipv4_srchashtbl) = NULL;
#define V_ipv4_hashtbl VNET(ipv4_hashtbl)
#define V_ipv4_srchashtbl VNET(ipv4_srchashtbl)
#define GRE_HASH(src, dst) (V_ipv4_hashtbl[\
in_gre_hashval((src), (dst)) & (GRE_HASH_SIZE - 1)])
#define GRE_SRCHASH(src) (V_ipv4_srchashtbl[\
fnv_32_buf(&(src), sizeof(src), FNV1_32_INIT) & (GRE_HASH_SIZE - 1)])
#define GRE_HASH_SC(sc) GRE_HASH((sc)->gre_oip.ip_src.s_addr,\
(sc)->gre_oip.ip_dst.s_addr)
static uint32_t
in_gre_hashval(in_addr_t src, in_addr_t dst)
{
uint32_t ret;
ret = fnv_32_buf(&src, sizeof(src), FNV1_32_INIT);
return (fnv_32_buf(&dst, sizeof(dst), ret));
}
static int
in_gre_checkdup(const struct gre_softc *sc, in_addr_t src, in_addr_t dst)
{
struct gre_softc *tmp;
if (sc->gre_family == AF_INET &&
sc->gre_oip.ip_src.s_addr == src &&
sc->gre_oip.ip_dst.s_addr == dst)
return (EEXIST);
CK_LIST_FOREACH(tmp, &GRE_HASH(src, dst), chain) {
if (tmp == sc)
continue;
if (tmp->gre_oip.ip_src.s_addr == src &&
tmp->gre_oip.ip_dst.s_addr == dst)
return (EADDRNOTAVAIL);
}
return (0);
}
static int
in_gre_lookup(const struct mbuf *m, int off, int proto, void **arg)
{
const struct ip *ip;
struct gre_softc *sc;
if (V_ipv4_hashtbl == NULL)
return (0);
MPASS(in_epoch(net_epoch_preempt));
ip = mtod(m, const struct ip *);
CK_LIST_FOREACH(sc, &GRE_HASH(ip->ip_dst.s_addr,
ip->ip_src.s_addr), chain) {
/*
* This is an inbound packet, its ip_dst is source address
* in softc.
*/
if (sc->gre_oip.ip_src.s_addr == ip->ip_dst.s_addr &&
sc->gre_oip.ip_dst.s_addr == ip->ip_src.s_addr) {
if ((GRE2IFP(sc)->if_flags & IFF_UP) == 0)
return (0);
*arg = sc;
return (ENCAP_DRV_LOOKUP);
}
}
return (0);
}
/*
* Check that ingress address belongs to local host.
*/
static void
in_gre_set_running(struct gre_softc *sc)
{
if (in_localip(sc->gre_oip.ip_src))
GRE2IFP(sc)->if_drv_flags |= IFF_DRV_RUNNING;
else
GRE2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
}
/*
* ifaddr_event handler.
* Clear IFF_DRV_RUNNING flag when ingress address disappears to prevent
* source address spoofing.
*/
static void
in_gre_srcaddr(void *arg __unused, const struct sockaddr *sa,
int event __unused)
{
const struct sockaddr_in *sin;
struct gre_softc *sc;
/* Check that VNET is ready */
if (V_ipv4_hashtbl == NULL)
return;
MPASS(in_epoch(net_epoch_preempt));
sin = (const struct sockaddr_in *)sa;
CK_LIST_FOREACH(sc, &GRE_SRCHASH(sin->sin_addr.s_addr), srchash) {
if (sc->gre_oip.ip_src.s_addr != sin->sin_addr.s_addr)
continue;
in_gre_set_running(sc);
}
}
static void
in_gre_attach(struct gre_softc *sc)
{
sc->gre_hlen = sizeof(struct greip);
sc->gre_oip.ip_v = IPVERSION;
sc->gre_oip.ip_hl = sizeof(struct ip) >> 2;
sc->gre_oip.ip_p = IPPROTO_GRE;
gre_updatehdr(sc, &sc->gre_gihdr->gi_gre);
CK_LIST_INSERT_HEAD(&GRE_HASH_SC(sc), sc, chain);
CK_LIST_INSERT_HEAD(&GRE_SRCHASH(sc->gre_oip.ip_src.s_addr),
sc, srchash);
}
void
in_gre_setopts(struct gre_softc *sc, u_long cmd, uint32_t value)
{
MPASS(cmd == GRESKEY || cmd == GRESOPTS);
/* NOTE: we are protected with gre_ioctl_sx lock */
MPASS(sc->gre_family == AF_INET);
CK_LIST_REMOVE(sc, chain);
CK_LIST_REMOVE(sc, srchash);
GRE_WAIT();
if (cmd == GRESKEY)
sc->gre_key = value;
else
sc->gre_options = value;
in_gre_attach(sc);
}
int
in_gre_ioctl(struct gre_softc *sc, u_long cmd, caddr_t data)
{
struct ifreq *ifr = (struct ifreq *)data;
struct sockaddr_in *dst, *src;
struct ip *ip;
int error;
/* NOTE: we are protected with gre_ioctl_sx lock */
error = EINVAL;
switch (cmd) {
case SIOCSIFPHYADDR:
src = &((struct in_aliasreq *)data)->ifra_addr;
dst = &((struct in_aliasreq *)data)->ifra_dstaddr;
/* sanity checks */
if (src->sin_family != dst->sin_family ||
src->sin_family != AF_INET ||
src->sin_len != dst->sin_len ||
src->sin_len != sizeof(*src))
break;
if (src->sin_addr.s_addr == INADDR_ANY ||
dst->sin_addr.s_addr == INADDR_ANY) {
error = EADDRNOTAVAIL;
break;
}
if (V_ipv4_hashtbl == NULL) {
V_ipv4_hashtbl = gre_hashinit();
V_ipv4_srchashtbl = gre_hashinit();
}
error = in_gre_checkdup(sc, src->sin_addr.s_addr,
dst->sin_addr.s_addr);
if (error == EADDRNOTAVAIL)
break;
if (error == EEXIST) {
/* Addresses are the same. Just return. */
error = 0;
break;
}
ip = malloc(sizeof(struct greip) + 3 * sizeof(uint32_t),
M_GRE, M_WAITOK | M_ZERO);
ip->ip_src.s_addr = src->sin_addr.s_addr;
ip->ip_dst.s_addr = dst->sin_addr.s_addr;
if (sc->gre_family != 0) {
/* Detach existing tunnel first */
CK_LIST_REMOVE(sc, chain);
CK_LIST_REMOVE(sc, srchash);
GRE_WAIT();
free(sc->gre_hdr, M_GRE);
/* XXX: should we notify about link state change? */
}
sc->gre_family = AF_INET;
sc->gre_hdr = ip;
sc->gre_oseq = 0;
sc->gre_iseq = UINT32_MAX;
in_gre_attach(sc);
in_gre_set_running(sc);
break;
case SIOCGIFPSRCADDR:
case SIOCGIFPDSTADDR:
if (sc->gre_family != AF_INET) {
error = EADDRNOTAVAIL;
break;
}
src = (struct sockaddr_in *)&ifr->ifr_addr;
memset(src, 0, sizeof(*src));
src->sin_family = AF_INET;
src->sin_len = sizeof(*src);
src->sin_addr = (cmd == SIOCGIFPSRCADDR) ?
sc->gre_oip.ip_src: sc->gre_oip.ip_dst;
error = prison_if(curthread->td_ucred, (struct sockaddr *)src);
if (error != 0)
memset(src, 0, sizeof(*src));
break;
}
return (error);
}
int
in_gre_output(struct mbuf *m, int af, int hlen)
{
struct greip *gi;
gi = mtod(m, struct greip *);
switch (af) {
case AF_INET:
/*
* gre_transmit() has used M_PREPEND() that doesn't guarantee
* m_data is contiguous more than hlen bytes. Use m_copydata()
* here to avoid m_pullup().
*/
m_copydata(m, hlen + offsetof(struct ip, ip_tos),
sizeof(u_char), &gi->gi_ip.ip_tos);
m_copydata(m, hlen + offsetof(struct ip, ip_id),
sizeof(u_short), (caddr_t)&gi->gi_ip.ip_id);
break;
#ifdef INET6
case AF_INET6:
gi->gi_ip.ip_tos = 0; /* XXX */
ip_fillid(&gi->gi_ip);
break;
#endif
}
gi->gi_ip.ip_ttl = V_ip_gre_ttl;
gi->gi_ip.ip_len = htons(m->m_pkthdr.len);
return (ip_output(m, NULL, NULL, IP_FORWARDING, NULL, NULL));
}
static const struct srcaddrtab *ipv4_srcaddrtab = NULL;
static const struct encaptab *ecookie = NULL;
static const struct encap_config ipv4_encap_cfg = {
.proto = IPPROTO_GRE,
.min_length = sizeof(struct greip) + sizeof(struct ip),
.exact_match = ENCAP_DRV_LOOKUP,
.lookup = in_gre_lookup,
.input = gre_input
};
void
in_gre_init(void)
{
if (!IS_DEFAULT_VNET(curvnet))
return;
ipv4_srcaddrtab = ip_encap_register_srcaddr(in_gre_srcaddr,
NULL, M_WAITOK);
ecookie = ip_encap_attach(&ipv4_encap_cfg, NULL, M_WAITOK);
}
void
in_gre_uninit(void)
{
if (IS_DEFAULT_VNET(curvnet)) {
ip_encap_detach(ecookie);
ip_encap_unregister_srcaddr(ipv4_srcaddrtab);
}
if (V_ipv4_hashtbl != NULL) {
gre_hashdestroy(V_ipv4_hashtbl);
V_ipv4_hashtbl = NULL;
GRE_WAIT();
gre_hashdestroy(V_ipv4_srchashtbl);
}
}
