if_faith.c revision 241610 
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 241610 2012-10-16 13:37:54Z glebius $
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#include <net/vnet.h>
65
66#ifdef	INET
67#include <netinet/in.h>
68#include <netinet/in_systm.h>
69#include <netinet/in_var.h>
70#include <netinet/ip.h>
71#endif
72
73#ifdef INET6
74#ifndef INET
75#include <netinet/in.h>
76#endif
77#include <netinet6/in6_var.h>
78#include <netinet/ip6.h>
79#include <netinet6/ip6_var.h>
80#endif
81
82struct faith_softc {
83	struct ifnet *sc_ifp;
84};
85
86static int faithioctl(struct ifnet *, u_long, caddr_t);
87int faithoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
88	struct route *);
89static void faithrtrequest(int, struct rtentry *, struct rt_addrinfo *);
90#ifdef INET6
91static int faithprefix(struct in6_addr *);
92#endif
93
94static int faithmodevent(module_t, int, void *);
95
96static const char faithname[] = "faith";
97static MALLOC_DEFINE(M_FAITH, faithname, "Firewall Assisted Tunnel Interface");
98
99static int	faith_clone_create(struct if_clone *, int, caddr_t);
100static void	faith_clone_destroy(struct ifnet *);
101static struct if_clone *faith_cloner;
102
103#define	FAITHMTU	1500
104
105static int
106faithmodevent(mod, type, data)
107	module_t mod;
108	int type;
109	void *data;
110{
111
112	switch (type) {
113	case MOD_LOAD:
114		faith_cloner = if_clone_simple(faithname, faith_clone_create,
115		    faith_clone_destroy, 0);
116#ifdef INET6
117		faithprefix_p = faithprefix;
118#endif
119
120		break;
121	case MOD_UNLOAD:
122#ifdef INET6
123		faithprefix_p = NULL;
124#endif
125
126		if_clone_detach(faith_cloner);
127		break;
128	default:
129		return EOPNOTSUPP;
130	}
131	return 0;
132}
133
134static moduledata_t faith_mod = {
135	"if_faith",
136	faithmodevent,
137	0
138};
139
140DECLARE_MODULE(if_faith, faith_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
141MODULE_VERSION(if_faith, 1);
142
143static int
144faith_clone_create(ifc, unit, params)
145	struct if_clone *ifc;
146	int unit;
147	caddr_t params;
148{
149	struct ifnet *ifp;
150	struct faith_softc *sc;
151
152	sc = malloc(sizeof(struct faith_softc), M_FAITH, M_WAITOK | M_ZERO);
153	ifp = sc->sc_ifp = if_alloc(IFT_FAITH);
154	if (ifp == NULL) {
155		free(sc, M_FAITH);
156		return (ENOSPC);
157	}
158
159	ifp->if_softc = sc;
160	if_initname(sc->sc_ifp, faithname, unit);
161
162	ifp->if_mtu = FAITHMTU;
163	/* Change to BROADCAST experimentaly to announce its prefix. */
164	ifp->if_flags = /* IFF_LOOPBACK */ IFF_BROADCAST | IFF_MULTICAST;
165	ifp->if_ioctl = faithioctl;
166	ifp->if_output = faithoutput;
167	ifp->if_hdrlen = 0;
168	ifp->if_addrlen = 0;
169	ifp->if_snd.ifq_maxlen = ifqmaxlen;
170	if_attach(ifp);
171	bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
172	return (0);
173}
174
175static void
176faith_clone_destroy(ifp)
177	struct ifnet *ifp;
178{
179	struct faith_softc *sc = ifp->if_softc;
180
181	bpfdetach(ifp);
182	if_detach(ifp);
183	if_free(ifp);
184	free(sc, M_FAITH);
185}
186
187int
188faithoutput(ifp, m, dst, ro)
189	struct ifnet *ifp;
190	struct mbuf *m;
191	struct sockaddr *dst;
192	struct route *ro;
193{
194	int isr;
195	u_int32_t af;
196	struct rtentry *rt = NULL;
197
198	M_ASSERTPKTHDR(m);
199
200	if (ro != NULL)
201		rt = ro->ro_rt;
202	/* BPF writes need to be handled specially. */
203	if (dst->sa_family == AF_UNSPEC) {
204		bcopy(dst->sa_data, &af, sizeof(af));
205		dst->sa_family = af;
206	}
207
208	if (bpf_peers_present(ifp->if_bpf)) {
209		af = dst->sa_family;
210		bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
211	}
212
213	if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
214		m_freem(m);
215		return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
216		        rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
217	}
218	ifp->if_opackets++;
219	ifp->if_obytes += m->m_pkthdr.len;
220	switch (dst->sa_family) {
221#ifdef INET
222	case AF_INET:
223		isr = NETISR_IP;
224		break;
225#endif
226#ifdef INET6
227	case AF_INET6:
228		isr = NETISR_IPV6;
229		break;
230#endif
231	default:
232		m_freem(m);
233		return EAFNOSUPPORT;
234	}
235
236	/* XXX do we need more sanity checks? */
237
238	m->m_pkthdr.rcvif = ifp;
239	ifp->if_ipackets++;
240	ifp->if_ibytes += m->m_pkthdr.len;
241	netisr_dispatch(isr, m);
242	return (0);
243}
244
245/* ARGSUSED */
246static void
247faithrtrequest(cmd, rt, info)
248	int cmd;
249	struct rtentry *rt;
250	struct rt_addrinfo *info;
251{
252	RT_LOCK_ASSERT(rt);
253	rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu;
254}
255
256/*
257 * Process an ioctl request.
258 */
259/* ARGSUSED */
260static int
261faithioctl(ifp, cmd, data)
262	struct ifnet *ifp;
263	u_long cmd;
264	caddr_t data;
265{
266	struct ifaddr *ifa;
267	struct ifreq *ifr = (struct ifreq *)data;
268	int error = 0;
269
270	switch (cmd) {
271
272	case SIOCSIFADDR:
273		ifp->if_flags |= IFF_UP;
274		ifp->if_drv_flags |= IFF_DRV_RUNNING;
275		ifa = (struct ifaddr *)data;
276		ifa->ifa_rtrequest = faithrtrequest;
277		/*
278		 * Everything else is done at a higher level.
279		 */
280		break;
281
282	case SIOCADDMULTI:
283	case SIOCDELMULTI:
284		if (ifr == 0) {
285			error = EAFNOSUPPORT;		/* XXX */
286			break;
287		}
288		switch (ifr->ifr_addr.sa_family) {
289#ifdef INET
290		case AF_INET:
291			break;
292#endif
293#ifdef INET6
294		case AF_INET6:
295			break;
296#endif
297
298		default:
299			error = EAFNOSUPPORT;
300			break;
301		}
302		break;
303
304#ifdef SIOCSIFMTU
305	case SIOCSIFMTU:
306		ifp->if_mtu = ifr->ifr_mtu;
307		break;
308#endif
309
310	case SIOCSIFFLAGS:
311		break;
312
313	default:
314		error = EINVAL;
315	}
316	return (error);
317}
318
319#ifdef INET6
320/*
321 * XXX could be slow
322 * XXX could be layer violation to call sys/net from sys/netinet6
323 */
324static int
325faithprefix(in6)
326	struct in6_addr *in6;
327{
328	struct rtentry *rt;
329	struct sockaddr_in6 sin6;
330	int ret;
331
332	if (V_ip6_keepfaith == 0)
333		return 0;
334
335	bzero(&sin6, sizeof(sin6));
336	sin6.sin6_family = AF_INET6;
337	sin6.sin6_len = sizeof(struct sockaddr_in6);
338	sin6.sin6_addr = *in6;
339	rt = in6_rtalloc1((struct sockaddr *)&sin6, 0, 0UL, RT_DEFAULT_FIB);
340	if (rt && rt->rt_ifp && rt->rt_ifp->if_type == IFT_FAITH &&
341	    (rt->rt_ifp->if_flags & IFF_UP) != 0)
342		ret = 1;
343	else
344		ret = 0;
345	if (rt)
346		RTFREE_LOCKED(rt);
347	return ret;
348}
349#endif
350