if_faith.c revision 191148 
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 191148 2009-04-16 20:30:28Z kmacy $
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#include <sys/vimage.h>
58
59#include <net/if.h>
60#include <net/if_clone.h>
61#include <net/if_types.h>
62#include <net/netisr.h>
63#include <net/route.h>
64#include <net/bpf.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#include <netinet6/vinet6.h>
81#endif
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 route *);
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, caddr_t);
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, params)
148	struct if_clone *ifc;
149	int unit;
150	caddr_t params;
151{
152	struct ifnet *ifp;
153	struct faith_softc *sc;
154
155	sc = malloc(sizeof(struct faith_softc), M_FAITH, M_WAITOK | M_ZERO);
156	ifp = sc->sc_ifp = if_alloc(IFT_FAITH);
157	if (ifp == NULL) {
158		free(sc, M_FAITH);
159		return (ENOSPC);
160	}
161
162	ifp->if_softc = sc;
163	if_initname(sc->sc_ifp, ifc->ifc_name, unit);
164
165	ifp->if_mtu = FAITHMTU;
166	/* Change to BROADCAST experimentaly to announce its prefix. */
167	ifp->if_flags = /* IFF_LOOPBACK */ IFF_BROADCAST | IFF_MULTICAST;
168	ifp->if_ioctl = faithioctl;
169	ifp->if_output = faithoutput;
170	ifp->if_hdrlen = 0;
171	ifp->if_addrlen = 0;
172	ifp->if_snd.ifq_maxlen = ifqmaxlen;
173	if_attach(ifp);
174	bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
175	return (0);
176}
177
178static void
179faith_clone_destroy(ifp)
180	struct ifnet *ifp;
181{
182	struct faith_softc *sc = ifp->if_softc;
183
184	bpfdetach(ifp);
185	if_detach(ifp);
186	if_free(ifp);
187	free(sc, M_FAITH);
188}
189
190int
191faithoutput(ifp, m, dst, ro)
192	struct ifnet *ifp;
193	struct mbuf *m;
194	struct sockaddr *dst;
195	struct route *ro;
196{
197	int isr;
198	u_int32_t af;
199	struct rtentry *rt = NULL;
200
201	M_ASSERTPKTHDR(m);
202
203	if (ro != NULL)
204		rt = ro->ro_rt;
205	/* BPF writes need to be handled specially. */
206	if (dst->sa_family == AF_UNSPEC) {
207		bcopy(dst->sa_data, &af, sizeof(af));
208		dst->sa_family = af;
209	}
210
211	if (bpf_peers_present(ifp->if_bpf)) {
212		af = dst->sa_family;
213		bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
214	}
215
216	if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
217		m_freem(m);
218		return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
219		        rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
220	}
221	ifp->if_opackets++;
222	ifp->if_obytes += m->m_pkthdr.len;
223	switch (dst->sa_family) {
224#ifdef INET
225	case AF_INET:
226		isr = NETISR_IP;
227		break;
228#endif
229#ifdef INET6
230	case AF_INET6:
231		isr = NETISR_IPV6;
232		break;
233#endif
234	default:
235		m_freem(m);
236		return EAFNOSUPPORT;
237	}
238
239	/* XXX do we need more sanity checks? */
240
241	m->m_pkthdr.rcvif = ifp;
242	ifp->if_ipackets++;
243	ifp->if_ibytes += m->m_pkthdr.len;
244	netisr_dispatch(isr, m);
245	return (0);
246}
247
248/* ARGSUSED */
249static void
250faithrtrequest(cmd, rt, info)
251	int cmd;
252	struct rtentry *rt;
253	struct rt_addrinfo *info;
254{
255	RT_LOCK_ASSERT(rt);
256	rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu;
257}
258
259/*
260 * Process an ioctl request.
261 */
262/* ARGSUSED */
263static int
264faithioctl(ifp, cmd, data)
265	struct ifnet *ifp;
266	u_long cmd;
267	caddr_t data;
268{
269	struct ifaddr *ifa;
270	struct ifreq *ifr = (struct ifreq *)data;
271	int error = 0;
272
273	switch (cmd) {
274
275	case SIOCSIFADDR:
276		ifp->if_flags |= IFF_UP;
277		ifp->if_drv_flags |= IFF_DRV_RUNNING;
278		ifa = (struct ifaddr *)data;
279		ifa->ifa_rtrequest = faithrtrequest;
280		/*
281		 * Everything else is done at a higher level.
282		 */
283		break;
284
285	case SIOCADDMULTI:
286	case SIOCDELMULTI:
287		if (ifr == 0) {
288			error = EAFNOSUPPORT;		/* XXX */
289			break;
290		}
291		switch (ifr->ifr_addr.sa_family) {
292#ifdef INET
293		case AF_INET:
294			break;
295#endif
296#ifdef INET6
297		case AF_INET6:
298			break;
299#endif
300
301		default:
302			error = EAFNOSUPPORT;
303			break;
304		}
305		break;
306
307#ifdef SIOCSIFMTU
308	case SIOCSIFMTU:
309		ifp->if_mtu = ifr->ifr_mtu;
310		break;
311#endif
312
313	case SIOCSIFFLAGS:
314		break;
315
316	default:
317		error = EINVAL;
318	}
319	return (error);
320}
321
322#ifdef INET6
323/*
324 * XXX could be slow
325 * XXX could be layer violation to call sys/net from sys/netinet6
326 */
327static int
328faithprefix(in6)
329	struct in6_addr *in6;
330{
331	INIT_VNET_INET6(curvnet);
332	struct rtentry *rt;
333	struct sockaddr_in6 sin6;
334	int ret;
335
336	if (V_ip6_keepfaith == 0)
337		return 0;
338
339	bzero(&sin6, sizeof(sin6));
340	sin6.sin6_family = AF_INET6;
341	sin6.sin6_len = sizeof(struct sockaddr_in6);
342	sin6.sin6_addr = *in6;
343	rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL);
344	if (rt && rt->rt_ifp && rt->rt_ifp->if_type == IFT_FAITH &&
345	    (rt->rt_ifp->if_flags & IFF_UP) != 0)
346		ret = 1;
347	else
348		ret = 0;
349	if (rt)
350		RTFREE_LOCKED(rt);
351	return ret;
352}
353#endif
354