freebsd-dev/sys/netinet6/in6_gif.c
Pedro F. Giffuni 51369649b0 sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00

233 lines
6.3 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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: in6_gif.c,v 1.49 2001/05/14 14:02:17 itojun Exp $
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/rmlock.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/queue.h>
#include <sys/syslog.h>
#include <sys/sysctl.h>
#include <sys/protosw.h>
#include <sys/malloc.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#ifdef INET
#include <netinet/ip.h>
#endif
#include <netinet/ip_encap.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_var.h>
#endif
#include <netinet/ip_ecn.h>
#ifdef INET6
#include <netinet6/ip6_ecn.h>
#include <netinet6/in6_fib.h>
#endif
#include <net/if_gif.h>
#define GIF_HLIM 30
static VNET_DEFINE(int, ip6_gif_hlim) = GIF_HLIM;
#define V_ip6_gif_hlim VNET(ip6_gif_hlim)
SYSCTL_DECL(_net_inet6_ip6);
SYSCTL_INT(_net_inet6_ip6, IPV6CTL_GIF_HLIM, gifhlim, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(ip6_gif_hlim), 0, "");
static int in6_gif_input(struct mbuf **, int *, int);
extern struct domain inet6domain;
static struct protosw in6_gif_protosw = {
.pr_type = SOCK_RAW,
.pr_domain = &inet6domain,
.pr_protocol = 0, /* IPPROTO_IPV[46] */
.pr_flags = PR_ATOMIC|PR_ADDR,
.pr_input = in6_gif_input,
.pr_output = rip6_output,
.pr_ctloutput = rip6_ctloutput,
.pr_usrreqs = &rip6_usrreqs
};
int
in6_gif_output(struct ifnet *ifp, struct mbuf *m, int proto, uint8_t ecn)
{
GIF_RLOCK_TRACKER;
struct gif_softc *sc = ifp->if_softc;
struct ip6_hdr *ip6;
int len;
/* prepend new IP header */
len = sizeof(struct ip6_hdr);
#ifndef __NO_STRICT_ALIGNMENT
if (proto == IPPROTO_ETHERIP)
len += ETHERIP_ALIGN;
#endif
M_PREPEND(m, len, M_NOWAIT);
if (m == NULL)
return (ENOBUFS);
#ifndef __NO_STRICT_ALIGNMENT
if (proto == IPPROTO_ETHERIP) {
len = mtod(m, vm_offset_t) & 3;
KASSERT(len == 0 || len == ETHERIP_ALIGN,
("in6_gif_output: unexpected misalignment"));
m->m_data += len;
m->m_len -= ETHERIP_ALIGN;
}
#endif
ip6 = mtod(m, struct ip6_hdr *);
GIF_RLOCK(sc);
if (sc->gif_family != AF_INET6) {
m_freem(m);
GIF_RUNLOCK(sc);
return (ENETDOWN);
}
bcopy(sc->gif_ip6hdr, ip6, sizeof(struct ip6_hdr));
GIF_RUNLOCK(sc);
ip6->ip6_flow |= htonl((uint32_t)ecn << 20);
ip6->ip6_nxt = proto;
ip6->ip6_hlim = V_ip6_gif_hlim;
/*
* force fragmentation to minimum MTU, to avoid path MTU discovery.
* it is too painful to ask for resend of inner packet, to achieve
* path MTU discovery for encapsulated packets.
*/
return (ip6_output(m, 0, NULL, IPV6_MINMTU, 0, NULL, NULL));
}
static int
in6_gif_input(struct mbuf **mp, int *offp, int proto)
{
struct mbuf *m = *mp;
struct ifnet *gifp;
struct gif_softc *sc;
struct ip6_hdr *ip6;
uint8_t ecn;
sc = encap_getarg(m);
if (sc == NULL) {
m_freem(m);
IP6STAT_INC(ip6s_nogif);
return (IPPROTO_DONE);
}
gifp = GIF2IFP(sc);
if ((gifp->if_flags & IFF_UP) != 0) {
ip6 = mtod(m, struct ip6_hdr *);
ecn = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
m_adj(m, *offp);
gif_input(m, gifp, proto, ecn);
} else {
m_freem(m);
IP6STAT_INC(ip6s_nogif);
}
return (IPPROTO_DONE);
}
/*
* we know that we are in IFF_UP, outer address available, and outer family
* matched the physical addr family. see gif_encapcheck().
*/
int
in6_gif_encapcheck(const struct mbuf *m, int off, int proto, void *arg)
{
const struct ip6_hdr *ip6;
struct gif_softc *sc;
int ret;
/* sanity check done in caller */
sc = (struct gif_softc *)arg;
GIF_RLOCK_ASSERT(sc);
/*
* Check for address match. Note that the check is for an incoming
* packet. We should compare the *source* address in our configuration
* and the *destination* address of the packet, and vice versa.
*/
ip6 = mtod(m, const struct ip6_hdr *);
if (!IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_src, &ip6->ip6_dst))
return (0);
ret = 128;
if (!IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_dst, &ip6->ip6_src)) {
if ((sc->gif_options & GIF_IGNORE_SOURCE) == 0)
return (0);
} else
ret += 128;
/* ingress filters on outer source */
if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0) {
struct nhop6_basic nh6;
/* XXX empty scope id */
if (fib6_lookup_nh_basic(sc->gif_fibnum, &ip6->ip6_src, 0, 0, 0,
&nh6) != 0)
return (0);
if (nh6.nh_ifp != m->m_pkthdr.rcvif)
return (0);
}
return (ret);
}
int
in6_gif_attach(struct gif_softc *sc)
{
KASSERT(sc->gif_ecookie == NULL, ("gif_ecookie isn't NULL"));
sc->gif_ecookie = encap_attach_func(AF_INET6, -1, gif_encapcheck,
(void *)&in6_gif_protosw, sc);
if (sc->gif_ecookie == NULL)
return (EEXIST);
return (0);
}