if_faith.c revision 131675 
1/*	$KAME: if_faith.c,v 1.23 2001/12/17 13:55:29 sumikawa Exp $	*/
2
3/*
4 * Copyright (c) 1982, 1986, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 4. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * $FreeBSD: head/sys/net/if_faith.c 131675 2004-07-06 03:34:16Z bms $
32 */
33/*
34 * derived from
35 *	@(#)if_loop.c	8.1 (Berkeley) 6/10/93
36 * Id: if_loop.c,v 1.22 1996/06/19 16:24:10 wollman Exp
37 */
38
39/*
40 * Loopback interface driver for protocol testing and timing.
41 */
42#include "opt_inet.h"
43#include "opt_inet6.h"
44
45#include <sys/param.h>
46#include <sys/systm.h>
47#include <sys/kernel.h>
48#include <sys/mbuf.h>
49#include <sys/module.h>
50#include <sys/socket.h>
51#include <sys/errno.h>
52#include <sys/sockio.h>
53#include <sys/time.h>
54#include <sys/queue.h>
55#include <sys/types.h>
56#include <sys/malloc.h>
57
58#include <net/if.h>
59#include <net/if_clone.h>
60#include <net/if_types.h>
61#include <net/netisr.h>
62#include <net/route.h>
63#include <net/bpf.h>
64
65#ifdef	INET
66#include <netinet/in.h>
67#include <netinet/in_systm.h>
68#include <netinet/in_var.h>
69#include <netinet/ip.h>
70#endif
71
72#ifdef INET6
73#ifndef INET
74#include <netinet/in.h>
75#endif
76#include <netinet6/in6_var.h>
77#include <netinet/ip6.h>
78#include <netinet6/ip6_var.h>
79#endif
80
81#include <net/net_osdep.h>
82
83#define FAITHNAME	"faith"
84
85struct faith_softc {
86	struct ifnet sc_if;	/* must be first */
87	LIST_ENTRY(faith_softc) sc_list;
88};
89
90static int faithioctl(struct ifnet *, u_long, caddr_t);
91int faithoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
92	struct rtentry *);
93static void faithrtrequest(int, struct rtentry *, struct rt_addrinfo *);
94#ifdef INET6
95static int faithprefix(struct in6_addr *);
96#endif
97
98static int faithmodevent(module_t, int, void *);
99
100static struct mtx faith_mtx;
101static MALLOC_DEFINE(M_FAITH, FAITHNAME, "Firewall Assisted Tunnel Interface");
102static LIST_HEAD(, faith_softc) faith_softc_list;
103
104static int	faith_clone_create(struct if_clone *, int);
105static void	faith_clone_destroy(struct ifnet *);
106static void	faith_destroy(struct faith_softc *);
107
108IFC_SIMPLE_DECLARE(faith, 0);
109
110#define	FAITHMTU	1500
111
112static int
113faithmodevent(mod, type, data)
114	module_t mod;
115	int type;
116	void *data;
117{
118	struct faith_softc *sc;
119
120	switch (type) {
121	case MOD_LOAD:
122		mtx_init(&faith_mtx, "faith_mtx", NULL, MTX_DEF);
123		LIST_INIT(&faith_softc_list);
124		if_clone_attach(&faith_cloner);
125
126#ifdef INET6
127		faithprefix_p = faithprefix;
128#endif
129
130		break;
131	case MOD_UNLOAD:
132#ifdef INET6
133		faithprefix_p = NULL;
134#endif
135
136		if_clone_detach(&faith_cloner);
137
138		mtx_lock(&faith_mtx);
139		while ((sc = LIST_FIRST(&faith_softc_list)) != NULL) {
140			LIST_REMOVE(sc, sc_list);
141			mtx_unlock(&faith_mtx);
142			faith_destroy(sc);
143			mtx_lock(&faith_mtx);
144		}
145		mtx_unlock(&faith_mtx);
146		mtx_destroy(&faith_mtx);
147		break;
148	}
149	return 0;
150}
151
152static moduledata_t faith_mod = {
153	"if_faith",
154	faithmodevent,
155	0
156};
157
158DECLARE_MODULE(if_faith, faith_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
159MODULE_VERSION(if_faith, 1);
160
161static int
162faith_clone_create(ifc, unit)
163	struct if_clone *ifc;
164	int unit;
165{
166	struct faith_softc *sc;
167
168	sc = malloc(sizeof(struct faith_softc), M_FAITH, M_WAITOK | M_ZERO);
169
170	sc->sc_if.if_softc = sc;
171	if_initname(&sc->sc_if, ifc->ifc_name, unit);
172
173	sc->sc_if.if_mtu = FAITHMTU;
174	/* Change to BROADCAST experimentaly to announce its prefix. */
175	sc->sc_if.if_flags = /* IFF_LOOPBACK */ IFF_BROADCAST | IFF_MULTICAST;
176	sc->sc_if.if_ioctl = faithioctl;
177	sc->sc_if.if_output = faithoutput;
178	sc->sc_if.if_type = IFT_FAITH;
179	sc->sc_if.if_hdrlen = 0;
180	sc->sc_if.if_addrlen = 0;
181	sc->sc_if.if_snd.ifq_maxlen = ifqmaxlen;
182	if_attach(&sc->sc_if);
183	bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int));
184	mtx_lock(&faith_mtx);
185	LIST_INSERT_HEAD(&faith_softc_list, sc, sc_list);
186	mtx_unlock(&faith_mtx);
187	return (0);
188}
189
190static void
191faith_destroy(struct faith_softc *sc)
192{
193
194	bpfdetach(&sc->sc_if);
195	if_detach(&sc->sc_if);
196	free(sc, M_FAITH);
197}
198
199static void
200faith_clone_destroy(ifp)
201	struct ifnet *ifp;
202{
203	struct faith_softc *sc = (void *) ifp;
204
205	mtx_lock(&faith_mtx);
206	LIST_REMOVE(sc, sc_list);
207	mtx_unlock(&faith_mtx);
208
209	faith_destroy(sc);
210}
211
212int
213faithoutput(ifp, m, dst, rt)
214	struct ifnet *ifp;
215	struct mbuf *m;
216	struct sockaddr *dst;
217	struct rtentry *rt;
218{
219	int isr;
220
221	M_ASSERTPKTHDR(m);
222
223	/* BPF write needs to be handled specially */
224	if (dst->sa_family == AF_UNSPEC) {
225		dst->sa_family = *(mtod(m, int *));
226		m->m_len -= sizeof(int);
227		m->m_pkthdr.len -= sizeof(int);
228		m->m_data += sizeof(int);
229	}
230
231	if (ifp->if_bpf) {
232		u_int32_t af = dst->sa_family;
233		bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
234	}
235
236	if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
237		m_freem(m);
238		return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
239		        rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
240	}
241	ifp->if_opackets++;
242	ifp->if_obytes += m->m_pkthdr.len;
243	switch (dst->sa_family) {
244#ifdef INET
245	case AF_INET:
246		isr = NETISR_IP;
247		break;
248#endif
249#ifdef INET6
250	case AF_INET6:
251		isr = NETISR_IPV6;
252		break;
253#endif
254	default:
255		m_freem(m);
256		return EAFNOSUPPORT;
257	}
258
259	/* XXX do we need more sanity checks? */
260
261	m->m_pkthdr.rcvif = ifp;
262	ifp->if_ipackets++;
263	ifp->if_ibytes += m->m_pkthdr.len;
264	netisr_dispatch(isr, m);
265	return (0);
266}
267
268/* ARGSUSED */
269static void
270faithrtrequest(cmd, rt, info)
271	int cmd;
272	struct rtentry *rt;
273	struct rt_addrinfo *info;
274{
275	RT_LOCK_ASSERT(rt);
276	if (rt)
277		rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu;
278}
279
280/*
281 * Process an ioctl request.
282 */
283/* ARGSUSED */
284static int
285faithioctl(ifp, cmd, data)
286	struct ifnet *ifp;
287	u_long cmd;
288	caddr_t data;
289{
290	struct ifaddr *ifa;
291	struct ifreq *ifr = (struct ifreq *)data;
292	int error = 0;
293
294	switch (cmd) {
295
296	case SIOCSIFADDR:
297		ifp->if_flags |= IFF_UP | IFF_RUNNING;
298		ifa = (struct ifaddr *)data;
299		ifa->ifa_rtrequest = faithrtrequest;
300		/*
301		 * Everything else is done at a higher level.
302		 */
303		break;
304
305	case SIOCADDMULTI:
306	case SIOCDELMULTI:
307		if (ifr == 0) {
308			error = EAFNOSUPPORT;		/* XXX */
309			break;
310		}
311		switch (ifr->ifr_addr.sa_family) {
312#ifdef INET
313		case AF_INET:
314			break;
315#endif
316#ifdef INET6
317		case AF_INET6:
318			break;
319#endif
320
321		default:
322			error = EAFNOSUPPORT;
323			break;
324		}
325		break;
326
327#ifdef SIOCSIFMTU
328	case SIOCSIFMTU:
329		ifp->if_mtu = ifr->ifr_mtu;
330		break;
331#endif
332
333	case SIOCSIFFLAGS:
334		break;
335
336	default:
337		error = EINVAL;
338	}
339	return (error);
340}
341
342#ifdef INET6
343/*
344 * XXX could be slow
345 * XXX could be layer violation to call sys/net from sys/netinet6
346 */
347static int
348faithprefix(in6)
349	struct in6_addr *in6;
350{
351	struct rtentry *rt;
352	struct sockaddr_in6 sin6;
353	int ret;
354
355	if (ip6_keepfaith == 0)
356		return 0;
357
358	bzero(&sin6, sizeof(sin6));
359	sin6.sin6_family = AF_INET6;
360	sin6.sin6_len = sizeof(struct sockaddr_in6);
361	sin6.sin6_addr = *in6;
362	rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL);
363	if (rt && rt->rt_ifp && rt->rt_ifp->if_type == IFT_FAITH &&
364	    (rt->rt_ifp->if_flags & IFF_UP) != 0)
365		ret = 1;
366	else
367		ret = 0;
368	if (rt)
369		RTFREE_LOCKED(rt);
370	return ret;
371}
372#endif
373