if_faith.c revision 152209 
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 152209 2005-11-08 20:08:34Z thompsa $
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_ifp;
87};
88
89static int faithioctl(struct ifnet *, u_long, caddr_t);
90int faithoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
91	struct rtentry *);
92static void faithrtrequest(int, struct rtentry *, struct rt_addrinfo *);
93#ifdef INET6
94static int faithprefix(struct in6_addr *);
95#endif
96
97static int faithmodevent(module_t, int, void *);
98
99static MALLOC_DEFINE(M_FAITH, FAITHNAME, "Firewall Assisted Tunnel Interface");
100
101static int	faith_clone_create(struct if_clone *, int);
102static void	faith_clone_destroy(struct ifnet *);
103
104IFC_SIMPLE_DECLARE(faith, 0);
105
106#define	FAITHMTU	1500
107
108static int
109faithmodevent(mod, type, data)
110	module_t mod;
111	int type;
112	void *data;
113{
114
115	switch (type) {
116	case MOD_LOAD:
117		if_clone_attach(&faith_cloner);
118
119#ifdef INET6
120		faithprefix_p = faithprefix;
121#endif
122
123		break;
124	case MOD_UNLOAD:
125#ifdef INET6
126		faithprefix_p = NULL;
127#endif
128
129		if_clone_detach(&faith_cloner);
130		break;
131	default:
132		return EOPNOTSUPP;
133	}
134	return 0;
135}
136
137static moduledata_t faith_mod = {
138	"if_faith",
139	faithmodevent,
140	0
141};
142
143DECLARE_MODULE(if_faith, faith_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
144MODULE_VERSION(if_faith, 1);
145
146static int
147faith_clone_create(ifc, unit)
148	struct if_clone *ifc;
149	int unit;
150{
151	struct ifnet *ifp;
152	struct faith_softc *sc;
153
154	sc = malloc(sizeof(struct faith_softc), M_FAITH, M_WAITOK | M_ZERO);
155	ifp = sc->sc_ifp = if_alloc(IFT_FAITH);
156	if (ifp == NULL) {
157		free(sc, M_FAITH);
158		return (ENOSPC);
159	}
160
161	ifp->if_softc = sc;
162	if_initname(sc->sc_ifp, ifc->ifc_name, unit);
163
164	ifp->if_mtu = FAITHMTU;
165	/* Change to BROADCAST experimentaly to announce its prefix. */
166	ifp->if_flags = /* IFF_LOOPBACK */ IFF_BROADCAST | IFF_MULTICAST;
167	ifp->if_ioctl = faithioctl;
168	ifp->if_output = faithoutput;
169	ifp->if_hdrlen = 0;
170	ifp->if_addrlen = 0;
171	ifp->if_snd.ifq_maxlen = ifqmaxlen;
172	if_attach(ifp);
173	bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
174	return (0);
175}
176
177static void
178faith_clone_destroy(ifp)
179	struct ifnet *ifp;
180{
181	struct faith_softc *sc = ifp->if_softc;
182
183	bpfdetach(ifp);
184	if_detach(ifp);
185	if_free(ifp);
186	free(sc, M_FAITH);
187}
188
189int
190faithoutput(ifp, m, dst, rt)
191	struct ifnet *ifp;
192	struct mbuf *m;
193	struct sockaddr *dst;
194	struct rtentry *rt;
195{
196	int isr;
197	u_int32_t af;
198
199	M_ASSERTPKTHDR(m);
200
201	/* BPF writes need to be handled specially. */
202	if (dst->sa_family == AF_UNSPEC) {
203		bcopy(dst->sa_data, &af, sizeof(af));
204		dst->sa_family = af;
205	}
206
207	if (ifp->if_bpf) {
208		af = dst->sa_family;
209		bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
210	}
211
212	if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
213		m_freem(m);
214		return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
215		        rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
216	}
217	ifp->if_opackets++;
218	ifp->if_obytes += m->m_pkthdr.len;
219	switch (dst->sa_family) {
220#ifdef INET
221	case AF_INET:
222		isr = NETISR_IP;
223		break;
224#endif
225#ifdef INET6
226	case AF_INET6:
227		isr = NETISR_IPV6;
228		break;
229#endif
230	default:
231		m_freem(m);
232		return EAFNOSUPPORT;
233	}
234
235	/* XXX do we need more sanity checks? */
236
237	m->m_pkthdr.rcvif = ifp;
238	ifp->if_ipackets++;
239	ifp->if_ibytes += m->m_pkthdr.len;
240	netisr_dispatch(isr, m);
241	return (0);
242}
243
244/* ARGSUSED */
245static void
246faithrtrequest(cmd, rt, info)
247	int cmd;
248	struct rtentry *rt;
249	struct rt_addrinfo *info;
250{
251	RT_LOCK_ASSERT(rt);
252	rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu;
253}
254
255/*
256 * Process an ioctl request.
257 */
258/* ARGSUSED */
259static int
260faithioctl(ifp, cmd, data)
261	struct ifnet *ifp;
262	u_long cmd;
263	caddr_t data;
264{
265	struct ifaddr *ifa;
266	struct ifreq *ifr = (struct ifreq *)data;
267	int error = 0;
268
269	switch (cmd) {
270
271	case SIOCSIFADDR:
272		ifp->if_flags |= IFF_UP;
273		ifp->if_drv_flags |= IFF_DRV_RUNNING;
274		ifa = (struct ifaddr *)data;
275		ifa->ifa_rtrequest = faithrtrequest;
276		/*
277		 * Everything else is done at a higher level.
278		 */
279		break;
280
281	case SIOCADDMULTI:
282	case SIOCDELMULTI:
283		if (ifr == 0) {
284			error = EAFNOSUPPORT;		/* XXX */
285			break;
286		}
287		switch (ifr->ifr_addr.sa_family) {
288#ifdef INET
289		case AF_INET:
290			break;
291#endif
292#ifdef INET6
293		case AF_INET6:
294			break;
295#endif
296
297		default:
298			error = EAFNOSUPPORT;
299			break;
300		}
301		break;
302
303#ifdef SIOCSIFMTU
304	case SIOCSIFMTU:
305		ifp->if_mtu = ifr->ifr_mtu;
306		break;
307#endif
308
309	case SIOCSIFFLAGS:
310		break;
311
312	default:
313		error = EINVAL;
314	}
315	return (error);
316}
317
318#ifdef INET6
319/*
320 * XXX could be slow
321 * XXX could be layer violation to call sys/net from sys/netinet6
322 */
323static int
324faithprefix(in6)
325	struct in6_addr *in6;
326{
327	struct rtentry *rt;
328	struct sockaddr_in6 sin6;
329	int ret;
330
331	if (ip6_keepfaith == 0)
332		return 0;
333
334	bzero(&sin6, sizeof(sin6));
335	sin6.sin6_family = AF_INET6;
336	sin6.sin6_len = sizeof(struct sockaddr_in6);
337	sin6.sin6_addr = *in6;
338	rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL);
339	if (rt && rt->rt_ifp && rt->rt_ifp->if_type == IFT_FAITH &&
340	    (rt->rt_ifp->if_flags & IFF_UP) != 0)
341		ret = 1;
342	else
343		ret = 0;
344	if (rt)
345		RTFREE_LOCKED(rt);
346	return ret;
347}
348#endif
349