3
4/*
5 * Copyright (c) 1998 The NetBSD Foundation, Inc.
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to The NetBSD Foundation
9 * by Heiko W.Rupp <hwr@pilhuhn.de>
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the NetBSD
22 * Foundation, Inc. and its contributors.
23 * 4. Neither the name of The NetBSD Foundation nor the names of its
24 * contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
38 */
39
40/*
41 * Encapsulate L3 protocols into IP
42 * See RFC 1701 and 1702 for more details.
43 * If_gre is compatible with Cisco GRE tunnels, so you can
44 * have a NetBSD box as the other end of a tunnel interface of a Cisco
45 * router. See gre(4) for more details.
46 * Also supported: IP in IP encaps (proto 55) as of RFC 2004
47 */
48
49#include "opt_atalk.h"
50#include "opt_inet.h"
51#include "opt_inet6.h"
52
53#include <sys/param.h>
54#include <sys/kernel.h>
55#include <sys/malloc.h>
56#include <sys/module.h>
57#include <sys/mbuf.h>
58#include <sys/protosw.h>
59#include <sys/socket.h>
60#include <sys/sockio.h>
61#include <sys/sysctl.h>
62#include <sys/systm.h>
63
64#include <net/ethernet.h>
65#include <net/if.h>
66#include <net/if_clone.h>
67#include <net/if_types.h>
68#include <net/route.h>
69
70#ifdef INET
71#include <netinet/in.h>
72#include <netinet/in_systm.h>
73#include <netinet/in_var.h>
74#include <netinet/ip.h>
75#include <netinet/ip_gre.h>
76#include <netinet/ip_var.h>
77#include <netinet/ip_encap.h>
78#else
79#error "Huh? if_gre without inet?"
80#endif
81
82#include <net/bpf.h>
83
84#include <net/net_osdep.h>
85#include <net/if_gre.h>
86
87/*
88 * It is not easy to calculate the right value for a GRE MTU.
89 * We leave this task to the admin and use the same default that
90 * other vendors use.
91 */
92#define GREMTU 1476
93
94#define GRENAME "gre"
95
96/*
97 * gre_mtx protects all global variables in if_gre.c.
98 * XXX: gre_softc data not protected yet.
99 */
100struct mtx gre_mtx;
101static MALLOC_DEFINE(M_GRE, GRENAME, "Generic Routing Encapsulation");
102
103struct gre_softc_head gre_softc_list;
104
105static int gre_clone_create(struct if_clone *, int);
106static void gre_clone_destroy(struct ifnet *);
107static int gre_ioctl(struct ifnet *, u_long, caddr_t);
108static int gre_output(struct ifnet *, struct mbuf *, struct sockaddr *,
109 struct rtentry *rt);
110
111IFC_SIMPLE_DECLARE(gre, 0);
112
113static int gre_compute_route(struct gre_softc *sc);
114
115static void greattach(void);
116
117#ifdef INET
118extern struct domain inetdomain;
119static const struct protosw in_gre_protosw =
120{ SOCK_RAW, &inetdomain, IPPROTO_GRE, PR_ATOMIC|PR_ADDR,
121 (pr_input_t*)gre_input, (pr_output_t*)rip_output, rip_ctlinput, rip_ctloutput,
122 0,
123 0, 0, 0, 0,
124 &rip_usrreqs
125};
126static const struct protosw in_mobile_protosw =
127{ SOCK_RAW, &inetdomain, IPPROTO_MOBILE, PR_ATOMIC|PR_ADDR,
128 (pr_input_t*)gre_mobile_input, (pr_output_t*)rip_output, rip_ctlinput, rip_ctloutput,
129 0,
130 0, 0, 0, 0,
131 &rip_usrreqs
132};
133#endif
134
135SYSCTL_DECL(_net_link);
136SYSCTL_NODE(_net_link, IFT_TUNNEL, gre, CTLFLAG_RW, 0,
137 "Generic Routing Encapsulation");
138#ifndef MAX_GRE_NEST
139/*
140 * This macro controls the default upper limitation on nesting of gre tunnels.
141 * Since, setting a large value to this macro with a careless configuration
142 * may introduce system crash, we don't allow any nestings by default.
143 * If you need to configure nested gre tunnels, you can define this macro
144 * in your kernel configuration file. However, if you do so, please be
145 * careful to configure the tunnels so that it won't make a loop.
146 */
147#define MAX_GRE_NEST 1
148#endif
149static int max_gre_nesting = MAX_GRE_NEST;
150SYSCTL_INT(_net_link_gre, OID_AUTO, max_nesting, CTLFLAG_RW,
151 &max_gre_nesting, 0, "Max nested tunnels");
152
153/* ARGSUSED */
154static void
155greattach(void)
156{
157
158 mtx_init(&gre_mtx, "gre_mtx", NULL, MTX_DEF);
159 LIST_INIT(&gre_softc_list);
160 if_clone_attach(&gre_cloner);
161}
162
163static int
164gre_clone_create(ifc, unit)
165 struct if_clone *ifc;
166 int unit;
167{
168 struct gre_softc *sc;
169
170 sc = malloc(sizeof(struct gre_softc), M_GRE, M_WAITOK | M_ZERO);
171
172 if_initname(&sc->sc_if, ifc->ifc_name, unit);
173 sc->sc_if.if_softc = sc;
174 sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
175 sc->sc_if.if_type = IFT_TUNNEL;
176 sc->sc_if.if_addrlen = 0;
177 sc->sc_if.if_hdrlen = 24; /* IP + GRE */
178 sc->sc_if.if_mtu = GREMTU;
179 sc->sc_if.if_flags = IFF_POINTOPOINT|IFF_MULTICAST;
180 sc->sc_if.if_output = gre_output;
181 sc->sc_if.if_ioctl = gre_ioctl;
182 sc->g_dst.s_addr = sc->g_src.s_addr = INADDR_ANY;
183 sc->g_proto = IPPROTO_GRE;
184 sc->sc_if.if_flags |= IFF_LINK0;
185 sc->encap = NULL;
186 sc->called = 0;
187 sc->wccp_ver = WCCP_V1;
188 if_attach(&sc->sc_if);
189 bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int32_t));
190 mtx_lock(&gre_mtx);
191 LIST_INSERT_HEAD(&gre_softc_list, sc, sc_list);
192 mtx_unlock(&gre_mtx);
193 return (0);
194}
195
196static void
197gre_destroy(struct gre_softc *sc)
198{
199
200#ifdef INET
201 if (sc->encap != NULL)
202 encap_detach(sc->encap);
203#endif
204 bpfdetach(&sc->sc_if);
205 if_detach(&sc->sc_if);
206 free(sc, M_GRE);
207}
208
209static void
210gre_clone_destroy(ifp)
211 struct ifnet *ifp;
212{
213 struct gre_softc *sc = ifp->if_softc;
214
215 mtx_lock(&gre_mtx);
216 LIST_REMOVE(sc, sc_list);
217 mtx_unlock(&gre_mtx);
218 gre_destroy(sc);
219}
220
221/*
222 * The output routine. Takes a packet and encapsulates it in the protocol
223 * given by sc->g_proto. See also RFC 1701 and RFC 2004
224 */
225static int
226gre_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
227 struct rtentry *rt)
228{
229 int error = 0;
230 struct gre_softc *sc = ifp->if_softc;
231 struct greip *gh;
232 struct ip *ip;
233 u_int16_t etype = 0;
234 struct mobile_h mob_h;
235
236 /*
237 * gre may cause infinite recursion calls when misconfigured.
238 * We'll prevent this by introducing upper limit.
239 */
240 if (++(sc->called) > max_gre_nesting) {
241 printf("%s: gre_output: recursively called too many "
242 "times(%d)\n", if_name(&sc->sc_if), sc->called);
243 m_freem(m);
244 error = EIO; /* is there better errno? */
245 goto end;
246 }
247
248 if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) == 0 ||
249 sc->g_src.s_addr == INADDR_ANY || sc->g_dst.s_addr == INADDR_ANY) {
250 m_freem(m);
251 error = ENETDOWN;
252 goto end;
253 }
254
255 gh = NULL;
256 ip = NULL;
257
258 if (ifp->if_bpf) {
259 u_int32_t af = dst->sa_family;
260 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
261 }
262
263 m->m_flags &= ~(M_BCAST|M_MCAST);
264
265 if (sc->g_proto == IPPROTO_MOBILE) {
266 if (dst->sa_family == AF_INET) {
267 struct mbuf *m0;
268 int msiz;
269
270 ip = mtod(m, struct ip *);
271
272 /*
273 * RFC2004 specifies that fragmented diagrams shouldn't
274 * be encapsulated.
275 */
276 if ((ip->ip_off & IP_MF) != 0) {
277 _IF_DROP(&ifp->if_snd);
278 m_freem(m);
279 error = EINVAL; /* is there better errno? */
280 goto end;
281 }
282 memset(&mob_h, 0, MOB_H_SIZ_L);
283 mob_h.proto = (ip->ip_p) << 8;
284 mob_h.odst = ip->ip_dst.s_addr;
285 ip->ip_dst.s_addr = sc->g_dst.s_addr;
286
287 /*
288 * If the packet comes from our host, we only change
289 * the destination address in the IP header.
290 * Else we also need to save and change the source
291 */
292 if (in_hosteq(ip->ip_src, sc->g_src)) {
293 msiz = MOB_H_SIZ_S;
294 } else {
295 mob_h.proto |= MOB_H_SBIT;
296 mob_h.osrc = ip->ip_src.s_addr;
297 ip->ip_src.s_addr = sc->g_src.s_addr;
298 msiz = MOB_H_SIZ_L;
299 }
300 mob_h.proto = htons(mob_h.proto);
301 mob_h.hcrc = gre_in_cksum((u_int16_t *)&mob_h, msiz);
302
303 if ((m->m_data - msiz) < m->m_pktdat) {
304 /* need new mbuf */
305 MGETHDR(m0, M_DONTWAIT, MT_HEADER);
306 if (m0 == NULL) {
307 _IF_DROP(&ifp->if_snd);
308 m_freem(m);
309 error = ENOBUFS;
310 goto end;
311 }
312 m0->m_next = m;
313 m->m_data += sizeof(struct ip);
314 m->m_len -= sizeof(struct ip);
315 m0->m_pkthdr.len = m->m_pkthdr.len + msiz;
316 m0->m_len = msiz + sizeof(struct ip);
317 m0->m_data += max_linkhdr;
318 memcpy(mtod(m0, caddr_t), (caddr_t)ip,
319 sizeof(struct ip));
320 m = m0;
321 } else { /* we have some space left in the old one */
322 m->m_data -= msiz;
323 m->m_len += msiz;
324 m->m_pkthdr.len += msiz;
325 bcopy(ip, mtod(m, caddr_t),
326 sizeof(struct ip));
327 }
328 ip = mtod(m, struct ip *);
329 memcpy((caddr_t)(ip + 1), &mob_h, (unsigned)msiz);
330 ip->ip_len = ntohs(ip->ip_len) + msiz;
331 } else { /* AF_INET */
332 _IF_DROP(&ifp->if_snd);
333 m_freem(m);
334 error = EINVAL;
335 goto end;
336 }
337 } else if (sc->g_proto == IPPROTO_GRE) {
338 switch (dst->sa_family) {
339 case AF_INET:
340 ip = mtod(m, struct ip *);
341 etype = ETHERTYPE_IP;
342 break;
343#ifdef NETATALK
344 case AF_APPLETALK:
345 etype = ETHERTYPE_ATALK;
346 break;
347#endif
348 default:
349 _IF_DROP(&ifp->if_snd);
350 m_freem(m);
351 error = EAFNOSUPPORT;
352 goto end;
353 }
354 M_PREPEND(m, sizeof(struct greip), M_DONTWAIT);
355 } else {
356 _IF_DROP(&ifp->if_snd);
357 m_freem(m);
358 error = EINVAL;
359 goto end;
360 }
361
362 if (m == NULL) { /* mbuf allocation failed */
363 _IF_DROP(&ifp->if_snd);
364 error = ENOBUFS;
365 goto end;
366 }
367
368 gh = mtod(m, struct greip *);
369 if (sc->g_proto == IPPROTO_GRE) {
370 /* we don't have any GRE flags for now */
371 memset((void *)gh, 0, sizeof(struct greip));
372 gh->gi_ptype = htons(etype);
373 }
374
375 gh->gi_pr = sc->g_proto;
376 if (sc->g_proto != IPPROTO_MOBILE) {
377 gh->gi_src = sc->g_src;
378 gh->gi_dst = sc->g_dst;
| 3
4/*
5 * Copyright (c) 1998 The NetBSD Foundation, Inc.
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to The NetBSD Foundation
9 * by Heiko W.Rupp <hwr@pilhuhn.de>
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the NetBSD
22 * Foundation, Inc. and its contributors.
23 * 4. Neither the name of The NetBSD Foundation nor the names of its
24 * contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
38 */
39
40/*
41 * Encapsulate L3 protocols into IP
42 * See RFC 1701 and 1702 for more details.
43 * If_gre is compatible with Cisco GRE tunnels, so you can
44 * have a NetBSD box as the other end of a tunnel interface of a Cisco
45 * router. See gre(4) for more details.
46 * Also supported: IP in IP encaps (proto 55) as of RFC 2004
47 */
48
49#include "opt_atalk.h"
50#include "opt_inet.h"
51#include "opt_inet6.h"
52
53#include <sys/param.h>
54#include <sys/kernel.h>
55#include <sys/malloc.h>
56#include <sys/module.h>
57#include <sys/mbuf.h>
58#include <sys/protosw.h>
59#include <sys/socket.h>
60#include <sys/sockio.h>
61#include <sys/sysctl.h>
62#include <sys/systm.h>
63
64#include <net/ethernet.h>
65#include <net/if.h>
66#include <net/if_clone.h>
67#include <net/if_types.h>
68#include <net/route.h>
69
70#ifdef INET
71#include <netinet/in.h>
72#include <netinet/in_systm.h>
73#include <netinet/in_var.h>
74#include <netinet/ip.h>
75#include <netinet/ip_gre.h>
76#include <netinet/ip_var.h>
77#include <netinet/ip_encap.h>
78#else
79#error "Huh? if_gre without inet?"
80#endif
81
82#include <net/bpf.h>
83
84#include <net/net_osdep.h>
85#include <net/if_gre.h>
86
87/*
88 * It is not easy to calculate the right value for a GRE MTU.
89 * We leave this task to the admin and use the same default that
90 * other vendors use.
91 */
92#define GREMTU 1476
93
94#define GRENAME "gre"
95
96/*
97 * gre_mtx protects all global variables in if_gre.c.
98 * XXX: gre_softc data not protected yet.
99 */
100struct mtx gre_mtx;
101static MALLOC_DEFINE(M_GRE, GRENAME, "Generic Routing Encapsulation");
102
103struct gre_softc_head gre_softc_list;
104
105static int gre_clone_create(struct if_clone *, int);
106static void gre_clone_destroy(struct ifnet *);
107static int gre_ioctl(struct ifnet *, u_long, caddr_t);
108static int gre_output(struct ifnet *, struct mbuf *, struct sockaddr *,
109 struct rtentry *rt);
110
111IFC_SIMPLE_DECLARE(gre, 0);
112
113static int gre_compute_route(struct gre_softc *sc);
114
115static void greattach(void);
116
117#ifdef INET
118extern struct domain inetdomain;
119static const struct protosw in_gre_protosw =
120{ SOCK_RAW, &inetdomain, IPPROTO_GRE, PR_ATOMIC|PR_ADDR,
121 (pr_input_t*)gre_input, (pr_output_t*)rip_output, rip_ctlinput, rip_ctloutput,
122 0,
123 0, 0, 0, 0,
124 &rip_usrreqs
125};
126static const struct protosw in_mobile_protosw =
127{ SOCK_RAW, &inetdomain, IPPROTO_MOBILE, PR_ATOMIC|PR_ADDR,
128 (pr_input_t*)gre_mobile_input, (pr_output_t*)rip_output, rip_ctlinput, rip_ctloutput,
129 0,
130 0, 0, 0, 0,
131 &rip_usrreqs
132};
133#endif
134
135SYSCTL_DECL(_net_link);
136SYSCTL_NODE(_net_link, IFT_TUNNEL, gre, CTLFLAG_RW, 0,
137 "Generic Routing Encapsulation");
138#ifndef MAX_GRE_NEST
139/*
140 * This macro controls the default upper limitation on nesting of gre tunnels.
141 * Since, setting a large value to this macro with a careless configuration
142 * may introduce system crash, we don't allow any nestings by default.
143 * If you need to configure nested gre tunnels, you can define this macro
144 * in your kernel configuration file. However, if you do so, please be
145 * careful to configure the tunnels so that it won't make a loop.
146 */
147#define MAX_GRE_NEST 1
148#endif
149static int max_gre_nesting = MAX_GRE_NEST;
150SYSCTL_INT(_net_link_gre, OID_AUTO, max_nesting, CTLFLAG_RW,
151 &max_gre_nesting, 0, "Max nested tunnels");
152
153/* ARGSUSED */
154static void
155greattach(void)
156{
157
158 mtx_init(&gre_mtx, "gre_mtx", NULL, MTX_DEF);
159 LIST_INIT(&gre_softc_list);
160 if_clone_attach(&gre_cloner);
161}
162
163static int
164gre_clone_create(ifc, unit)
165 struct if_clone *ifc;
166 int unit;
167{
168 struct gre_softc *sc;
169
170 sc = malloc(sizeof(struct gre_softc), M_GRE, M_WAITOK | M_ZERO);
171
172 if_initname(&sc->sc_if, ifc->ifc_name, unit);
173 sc->sc_if.if_softc = sc;
174 sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
175 sc->sc_if.if_type = IFT_TUNNEL;
176 sc->sc_if.if_addrlen = 0;
177 sc->sc_if.if_hdrlen = 24; /* IP + GRE */
178 sc->sc_if.if_mtu = GREMTU;
179 sc->sc_if.if_flags = IFF_POINTOPOINT|IFF_MULTICAST;
180 sc->sc_if.if_output = gre_output;
181 sc->sc_if.if_ioctl = gre_ioctl;
182 sc->g_dst.s_addr = sc->g_src.s_addr = INADDR_ANY;
183 sc->g_proto = IPPROTO_GRE;
184 sc->sc_if.if_flags |= IFF_LINK0;
185 sc->encap = NULL;
186 sc->called = 0;
187 sc->wccp_ver = WCCP_V1;
188 if_attach(&sc->sc_if);
189 bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int32_t));
190 mtx_lock(&gre_mtx);
191 LIST_INSERT_HEAD(&gre_softc_list, sc, sc_list);
192 mtx_unlock(&gre_mtx);
193 return (0);
194}
195
196static void
197gre_destroy(struct gre_softc *sc)
198{
199
200#ifdef INET
201 if (sc->encap != NULL)
202 encap_detach(sc->encap);
203#endif
204 bpfdetach(&sc->sc_if);
205 if_detach(&sc->sc_if);
206 free(sc, M_GRE);
207}
208
209static void
210gre_clone_destroy(ifp)
211 struct ifnet *ifp;
212{
213 struct gre_softc *sc = ifp->if_softc;
214
215 mtx_lock(&gre_mtx);
216 LIST_REMOVE(sc, sc_list);
217 mtx_unlock(&gre_mtx);
218 gre_destroy(sc);
219}
220
221/*
222 * The output routine. Takes a packet and encapsulates it in the protocol
223 * given by sc->g_proto. See also RFC 1701 and RFC 2004
224 */
225static int
226gre_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
227 struct rtentry *rt)
228{
229 int error = 0;
230 struct gre_softc *sc = ifp->if_softc;
231 struct greip *gh;
232 struct ip *ip;
233 u_int16_t etype = 0;
234 struct mobile_h mob_h;
235
236 /*
237 * gre may cause infinite recursion calls when misconfigured.
238 * We'll prevent this by introducing upper limit.
239 */
240 if (++(sc->called) > max_gre_nesting) {
241 printf("%s: gre_output: recursively called too many "
242 "times(%d)\n", if_name(&sc->sc_if), sc->called);
243 m_freem(m);
244 error = EIO; /* is there better errno? */
245 goto end;
246 }
247
248 if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) == 0 ||
249 sc->g_src.s_addr == INADDR_ANY || sc->g_dst.s_addr == INADDR_ANY) {
250 m_freem(m);
251 error = ENETDOWN;
252 goto end;
253 }
254
255 gh = NULL;
256 ip = NULL;
257
258 if (ifp->if_bpf) {
259 u_int32_t af = dst->sa_family;
260 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
261 }
262
263 m->m_flags &= ~(M_BCAST|M_MCAST);
264
265 if (sc->g_proto == IPPROTO_MOBILE) {
266 if (dst->sa_family == AF_INET) {
267 struct mbuf *m0;
268 int msiz;
269
270 ip = mtod(m, struct ip *);
271
272 /*
273 * RFC2004 specifies that fragmented diagrams shouldn't
274 * be encapsulated.
275 */
276 if ((ip->ip_off & IP_MF) != 0) {
277 _IF_DROP(&ifp->if_snd);
278 m_freem(m);
279 error = EINVAL; /* is there better errno? */
280 goto end;
281 }
282 memset(&mob_h, 0, MOB_H_SIZ_L);
283 mob_h.proto = (ip->ip_p) << 8;
284 mob_h.odst = ip->ip_dst.s_addr;
285 ip->ip_dst.s_addr = sc->g_dst.s_addr;
286
287 /*
288 * If the packet comes from our host, we only change
289 * the destination address in the IP header.
290 * Else we also need to save and change the source
291 */
292 if (in_hosteq(ip->ip_src, sc->g_src)) {
293 msiz = MOB_H_SIZ_S;
294 } else {
295 mob_h.proto |= MOB_H_SBIT;
296 mob_h.osrc = ip->ip_src.s_addr;
297 ip->ip_src.s_addr = sc->g_src.s_addr;
298 msiz = MOB_H_SIZ_L;
299 }
300 mob_h.proto = htons(mob_h.proto);
301 mob_h.hcrc = gre_in_cksum((u_int16_t *)&mob_h, msiz);
302
303 if ((m->m_data - msiz) < m->m_pktdat) {
304 /* need new mbuf */
305 MGETHDR(m0, M_DONTWAIT, MT_HEADER);
306 if (m0 == NULL) {
307 _IF_DROP(&ifp->if_snd);
308 m_freem(m);
309 error = ENOBUFS;
310 goto end;
311 }
312 m0->m_next = m;
313 m->m_data += sizeof(struct ip);
314 m->m_len -= sizeof(struct ip);
315 m0->m_pkthdr.len = m->m_pkthdr.len + msiz;
316 m0->m_len = msiz + sizeof(struct ip);
317 m0->m_data += max_linkhdr;
318 memcpy(mtod(m0, caddr_t), (caddr_t)ip,
319 sizeof(struct ip));
320 m = m0;
321 } else { /* we have some space left in the old one */
322 m->m_data -= msiz;
323 m->m_len += msiz;
324 m->m_pkthdr.len += msiz;
325 bcopy(ip, mtod(m, caddr_t),
326 sizeof(struct ip));
327 }
328 ip = mtod(m, struct ip *);
329 memcpy((caddr_t)(ip + 1), &mob_h, (unsigned)msiz);
330 ip->ip_len = ntohs(ip->ip_len) + msiz;
331 } else { /* AF_INET */
332 _IF_DROP(&ifp->if_snd);
333 m_freem(m);
334 error = EINVAL;
335 goto end;
336 }
337 } else if (sc->g_proto == IPPROTO_GRE) {
338 switch (dst->sa_family) {
339 case AF_INET:
340 ip = mtod(m, struct ip *);
341 etype = ETHERTYPE_IP;
342 break;
343#ifdef NETATALK
344 case AF_APPLETALK:
345 etype = ETHERTYPE_ATALK;
346 break;
347#endif
348 default:
349 _IF_DROP(&ifp->if_snd);
350 m_freem(m);
351 error = EAFNOSUPPORT;
352 goto end;
353 }
354 M_PREPEND(m, sizeof(struct greip), M_DONTWAIT);
355 } else {
356 _IF_DROP(&ifp->if_snd);
357 m_freem(m);
358 error = EINVAL;
359 goto end;
360 }
361
362 if (m == NULL) { /* mbuf allocation failed */
363 _IF_DROP(&ifp->if_snd);
364 error = ENOBUFS;
365 goto end;
366 }
367
368 gh = mtod(m, struct greip *);
369 if (sc->g_proto == IPPROTO_GRE) {
370 /* we don't have any GRE flags for now */
371 memset((void *)gh, 0, sizeof(struct greip));
372 gh->gi_ptype = htons(etype);
373 }
374
375 gh->gi_pr = sc->g_proto;
376 if (sc->g_proto != IPPROTO_MOBILE) {
377 gh->gi_src = sc->g_src;
378 gh->gi_dst = sc->g_dst;
|
379 ((struct ip*)gh)->ip_hl = (sizeof(struct ip)) >> 2;
380 ((struct ip*)gh)->ip_ttl = GRE_TTL;
381 ((struct ip*)gh)->ip_tos = ip->ip_tos;
382 ((struct ip*)gh)->ip_id = ip->ip_id;
383 gh->gi_len = m->m_pkthdr.len;
384 }
385
386 ifp->if_opackets++;
387 ifp->if_obytes += m->m_pkthdr.len;
388 /*
389 * Send it off and with IP_FORWARD flag to prevent it from
390 * overwriting the ip_id again. ip_id is already set to the
391 * ip_id of the encapsulated packet.
392 */
393 error = ip_output(m, NULL, &sc->route, IP_FORWARDING,
394 (struct ip_moptions *)NULL, (struct inpcb *)NULL);
395 end:
396 sc->called = 0;
397 if (error)
398 ifp->if_oerrors++;
399 return (error);
400}
401
402static int
403gre_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
404{
405 struct ifreq *ifr = (struct ifreq *)data;
406 struct if_laddrreq *lifr = (struct if_laddrreq *)data;
407 struct in_aliasreq *aifr = (struct in_aliasreq *)data;
408 struct gre_softc *sc = ifp->if_softc;
409 int s;
410 struct sockaddr_in si;
411 struct sockaddr *sa = NULL;
412 int error;
413 struct sockaddr_in sp, sm, dp, dm;
414
415 error = 0;
416
417 s = splnet();
418 switch (cmd) {
419 case SIOCSIFADDR:
420 ifp->if_flags |= IFF_UP;
421 break;
422 case SIOCSIFDSTADDR:
423 break;
424 case SIOCSIFFLAGS:
425 if ((error = suser(curthread)) != 0)
426 break;
427 if ((ifr->ifr_flags & IFF_LINK0) != 0)
428 sc->g_proto = IPPROTO_GRE;
429 else
430 sc->g_proto = IPPROTO_MOBILE;
431 if ((ifr->ifr_flags & IFF_LINK2) != 0)
432 sc->wccp_ver = WCCP_V2;
433 else
434 sc->wccp_ver = WCCP_V1;
435 goto recompute;
436 case SIOCSIFMTU:
437 if ((error = suser(curthread)) != 0)
438 break;
439 if (ifr->ifr_mtu < 576) {
440 error = EINVAL;
441 break;
442 }
443 ifp->if_mtu = ifr->ifr_mtu;
444 break;
445 case SIOCGIFMTU:
446 ifr->ifr_mtu = sc->sc_if.if_mtu;
447 break;
448 case SIOCADDMULTI:
449 case SIOCDELMULTI:
450 if ((error = suser(curthread)) != 0)
451 break;
452 if (ifr == 0) {
453 error = EAFNOSUPPORT;
454 break;
455 }
456 switch (ifr->ifr_addr.sa_family) {
457#ifdef INET
458 case AF_INET:
459 break;
460#endif
461 default:
462 error = EAFNOSUPPORT;
463 break;
464 }
465 break;
466 case GRESPROTO:
467 if ((error = suser(curthread)) != 0)
468 break;
469 sc->g_proto = ifr->ifr_flags;
470 switch (sc->g_proto) {
471 case IPPROTO_GRE:
472 ifp->if_flags |= IFF_LINK0;
473 break;
474 case IPPROTO_MOBILE:
475 ifp->if_flags &= ~IFF_LINK0;
476 break;
477 default:
478 error = EPROTONOSUPPORT;
479 break;
480 }
481 goto recompute;
482 case GREGPROTO:
483 ifr->ifr_flags = sc->g_proto;
484 break;
485 case GRESADDRS:
486 case GRESADDRD:
487 if ((error = suser(curthread)) != 0)
488 break;
489 /*
490 * set tunnel endpoints, compute a less specific route
491 * to the remote end and mark if as up
492 */
493 sa = &ifr->ifr_addr;
494 if (cmd == GRESADDRS)
495 sc->g_src = (satosin(sa))->sin_addr;
496 if (cmd == GRESADDRD)
497 sc->g_dst = (satosin(sa))->sin_addr;
498 recompute:
499#ifdef INET
500 if (sc->encap != NULL) {
501 encap_detach(sc->encap);
502 sc->encap = NULL;
503 }
504#endif
505 if ((sc->g_src.s_addr != INADDR_ANY) &&
506 (sc->g_dst.s_addr != INADDR_ANY)) {
507 bzero(&sp, sizeof(sp));
508 bzero(&sm, sizeof(sm));
509 bzero(&dp, sizeof(dp));
510 bzero(&dm, sizeof(dm));
511 sp.sin_len = sm.sin_len = dp.sin_len = dm.sin_len =
512 sizeof(struct sockaddr_in);
513 sp.sin_family = sm.sin_family = dp.sin_family =
514 dm.sin_family = AF_INET;
515 sp.sin_addr = sc->g_src;
516 dp.sin_addr = sc->g_dst;
517 sm.sin_addr.s_addr = dm.sin_addr.s_addr =
518 INADDR_BROADCAST;
519#ifdef INET
520 sc->encap = encap_attach(AF_INET, sc->g_proto,
521 sintosa(&sp), sintosa(&sm), sintosa(&dp),
522 sintosa(&dm), (sc->g_proto == IPPROTO_GRE) ?
523 &in_gre_protosw : &in_mobile_protosw, sc);
524 if (sc->encap == NULL)
525 printf("%s: unable to attach encap\n",
526 if_name(&sc->sc_if));
527#endif
528 if (sc->route.ro_rt != 0) /* free old route */
529 RTFREE(sc->route.ro_rt);
530 if (gre_compute_route(sc) == 0)
531 ifp->if_flags |= IFF_RUNNING;
532 else
533 ifp->if_flags &= ~IFF_RUNNING;
534 }
535 break;
536 case GREGADDRS:
537 memset(&si, 0, sizeof(si));
538 si.sin_family = AF_INET;
539 si.sin_len = sizeof(struct sockaddr_in);
540 si.sin_addr.s_addr = sc->g_src.s_addr;
541 sa = sintosa(&si);
542 ifr->ifr_addr = *sa;
543 break;
544 case GREGADDRD:
545 memset(&si, 0, sizeof(si));
546 si.sin_family = AF_INET;
547 si.sin_len = sizeof(struct sockaddr_in);
548 si.sin_addr.s_addr = sc->g_dst.s_addr;
549 sa = sintosa(&si);
550 ifr->ifr_addr = *sa;
551 break;
552 case SIOCSIFPHYADDR:
553 if ((error = suser(curthread)) != 0)
554 break;
555 if (aifr->ifra_addr.sin_family != AF_INET ||
556 aifr->ifra_dstaddr.sin_family != AF_INET) {
557 error = EAFNOSUPPORT;
558 break;
559 }
560 if (aifr->ifra_addr.sin_len != sizeof(si) ||
561 aifr->ifra_dstaddr.sin_len != sizeof(si)) {
562 error = EINVAL;
563 break;
564 }
565 sc->g_src = aifr->ifra_addr.sin_addr;
566 sc->g_dst = aifr->ifra_dstaddr.sin_addr;
567 goto recompute;
568 case SIOCSLIFPHYADDR:
569 if ((error = suser(curthread)) != 0)
570 break;
571 if (lifr->addr.ss_family != AF_INET ||
572 lifr->dstaddr.ss_family != AF_INET) {
573 error = EAFNOSUPPORT;
574 break;
575 }
576 if (lifr->addr.ss_len != sizeof(si) ||
577 lifr->dstaddr.ss_len != sizeof(si)) {
578 error = EINVAL;
579 break;
580 }
581 sc->g_src = (satosin((struct sockadrr *)&lifr->addr))->sin_addr;
582 sc->g_dst =
583 (satosin((struct sockadrr *)&lifr->dstaddr))->sin_addr;
584 goto recompute;
585 case SIOCDIFPHYADDR:
586 if ((error = suser(curthread)) != 0)
587 break;
588 sc->g_src.s_addr = INADDR_ANY;
589 sc->g_dst.s_addr = INADDR_ANY;
590 goto recompute;
591 case SIOCGLIFPHYADDR:
592 if (sc->g_src.s_addr == INADDR_ANY ||
593 sc->g_dst.s_addr == INADDR_ANY) {
594 error = EADDRNOTAVAIL;
595 break;
596 }
597 memset(&si, 0, sizeof(si));
598 si.sin_family = AF_INET;
599 si.sin_len = sizeof(struct sockaddr_in);
600 si.sin_addr.s_addr = sc->g_src.s_addr;
601 memcpy(&lifr->addr, &si, sizeof(si));
602 si.sin_addr.s_addr = sc->g_dst.s_addr;
603 memcpy(&lifr->dstaddr, &si, sizeof(si));
604 break;
605 case SIOCGIFPSRCADDR:
606#ifdef INET6
607 case SIOCGIFPSRCADDR_IN6:
608#endif
609 if (sc->g_src.s_addr == INADDR_ANY) {
610 error = EADDRNOTAVAIL;
611 break;
612 }
613 memset(&si, 0, sizeof(si));
614 si.sin_family = AF_INET;
615 si.sin_len = sizeof(struct sockaddr_in);
616 si.sin_addr.s_addr = sc->g_src.s_addr;
617 bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr));
618 break;
619 case SIOCGIFPDSTADDR:
620#ifdef INET6
621 case SIOCGIFPDSTADDR_IN6:
622#endif
623 if (sc->g_dst.s_addr == INADDR_ANY) {
624 error = EADDRNOTAVAIL;
625 break;
626 }
627 memset(&si, 0, sizeof(si));
628 si.sin_family = AF_INET;
629 si.sin_len = sizeof(struct sockaddr_in);
630 si.sin_addr.s_addr = sc->g_dst.s_addr;
631 bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr));
632 break;
633 default:
634 error = EINVAL;
635 break;
636 }
637
638 splx(s);
639 return (error);
640}
641
642/*
643 * computes a route to our destination that is not the one
644 * which would be taken by ip_output(), as this one will loop back to
645 * us. If the interface is p2p as a--->b, then a routing entry exists
646 * If we now send a packet to b (e.g. ping b), this will come down here
647 * gets src=a, dst=b tacked on and would from ip_output() sent back to
648 * if_gre.
649 * Goal here is to compute a route to b that is less specific than
650 * a-->b. We know that this one exists as in normal operation we have
651 * at least a default route which matches.
652 */
653static int
654gre_compute_route(struct gre_softc *sc)
655{
656 struct route *ro;
657 u_int32_t a, b, c;
658
659 ro = &sc->route;
660
661 memset(ro, 0, sizeof(struct route));
662 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst;
663 ro->ro_dst.sa_family = AF_INET;
664 ro->ro_dst.sa_len = sizeof(ro->ro_dst);
665
666 /*
667 * toggle last bit, so our interface is not found, but a less
668 * specific route. I'd rather like to specify a shorter mask,
669 * but this is not possible. Should work though. XXX
670 * there is a simpler way ...
671 */
672 if ((sc->sc_if.if_flags & IFF_LINK1) == 0) {
673 a = ntohl(sc->g_dst.s_addr);
674 b = a & 0x01;
675 c = a & 0xfffffffe;
676 b = b ^ 0x01;
677 a = b | c;
678 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr.s_addr
679 = htonl(a);
680 }
681
682#ifdef DIAGNOSTIC
683 printf("%s: searching for a route to %s", if_name(&sc->sc_if),
684 inet_ntoa(((struct sockaddr_in *)&ro->ro_dst)->sin_addr));
685#endif
686
687 rtalloc(ro);
688
689 /*
690 * check if this returned a route at all and this route is no
691 * recursion to ourself
692 */
693 if (ro->ro_rt == NULL || ro->ro_rt->rt_ifp->if_softc == sc) {
694#ifdef DIAGNOSTIC
695 if (ro->ro_rt == NULL)
696 printf(" - no route found!\n");
697 else
698 printf(" - route loops back to ourself!\n");
699#endif
700 return EADDRNOTAVAIL;
701 }
702
703 /*
704 * now change it back - else ip_output will just drop
705 * the route and search one to this interface ...
706 */
707 if ((sc->sc_if.if_flags & IFF_LINK1) == 0)
708 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst;
709
710#ifdef DIAGNOSTIC
711 printf(", choosing %s with gateway %s", if_name(ro->ro_rt->rt_ifp),
712 inet_ntoa(((struct sockaddr_in *)(ro->ro_rt->rt_gateway))->sin_addr));
713 printf("\n");
714#endif
715
716 return 0;
717}
718
719/*
720 * do a checksum of a buffer - much like in_cksum, which operates on
721 * mbufs.
722 */
723u_int16_t
724gre_in_cksum(u_int16_t *p, u_int len)
725{
726 u_int32_t sum = 0;
727 int nwords = len >> 1;
728
729 while (nwords-- != 0)
730 sum += *p++;
731
732 if (len & 1) {
733 union {
734 u_short w;
735 u_char c[2];
736 } u;
737 u.c[0] = *(u_char *)p;
738 u.c[1] = 0;
739 sum += u.w;
740 }
741
742 /* end-around-carry */
743 sum = (sum >> 16) + (sum & 0xffff);
744 sum += (sum >> 16);
745 return (~sum);
746}
747
748static int
749gremodevent(module_t mod, int type, void *data)
750{
751 struct gre_softc *sc;
752
753 switch (type) {
754 case MOD_LOAD:
755 greattach();
756 break;
757 case MOD_UNLOAD:
758 if_clone_detach(&gre_cloner);
759
760 mtx_lock(&gre_mtx);
761 while ((sc = LIST_FIRST(&gre_softc_list)) != NULL) {
762 LIST_REMOVE(sc, sc_list);
763 mtx_unlock(&gre_mtx);
764 gre_destroy(sc);
765 mtx_lock(&gre_mtx);
766 }
767 mtx_unlock(&gre_mtx);
768 mtx_destroy(&gre_mtx);
769 break;
770 default:
771 return EOPNOTSUPP;
772 }
773 return 0;
774}
775
776static moduledata_t gre_mod = {
777 "if_gre",
778 gremodevent,
779 0
780};
781
782DECLARE_MODULE(if_gre, gre_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
783MODULE_VERSION(if_gre, 1);
| 380 ((struct ip*)gh)->ip_hl = (sizeof(struct ip)) >> 2;
381 ((struct ip*)gh)->ip_ttl = GRE_TTL;
382 ((struct ip*)gh)->ip_tos = ip->ip_tos;
383 ((struct ip*)gh)->ip_id = ip->ip_id;
384 gh->gi_len = m->m_pkthdr.len;
385 }
386
387 ifp->if_opackets++;
388 ifp->if_obytes += m->m_pkthdr.len;
389 /*
390 * Send it off and with IP_FORWARD flag to prevent it from
391 * overwriting the ip_id again. ip_id is already set to the
392 * ip_id of the encapsulated packet.
393 */
394 error = ip_output(m, NULL, &sc->route, IP_FORWARDING,
395 (struct ip_moptions *)NULL, (struct inpcb *)NULL);
396 end:
397 sc->called = 0;
398 if (error)
399 ifp->if_oerrors++;
400 return (error);
401}
402
403static int
404gre_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
405{
406 struct ifreq *ifr = (struct ifreq *)data;
407 struct if_laddrreq *lifr = (struct if_laddrreq *)data;
408 struct in_aliasreq *aifr = (struct in_aliasreq *)data;
409 struct gre_softc *sc = ifp->if_softc;
410 int s;
411 struct sockaddr_in si;
412 struct sockaddr *sa = NULL;
413 int error;
414 struct sockaddr_in sp, sm, dp, dm;
415
416 error = 0;
417
418 s = splnet();
419 switch (cmd) {
420 case SIOCSIFADDR:
421 ifp->if_flags |= IFF_UP;
422 break;
423 case SIOCSIFDSTADDR:
424 break;
425 case SIOCSIFFLAGS:
426 if ((error = suser(curthread)) != 0)
427 break;
428 if ((ifr->ifr_flags & IFF_LINK0) != 0)
429 sc->g_proto = IPPROTO_GRE;
430 else
431 sc->g_proto = IPPROTO_MOBILE;
432 if ((ifr->ifr_flags & IFF_LINK2) != 0)
433 sc->wccp_ver = WCCP_V2;
434 else
435 sc->wccp_ver = WCCP_V1;
436 goto recompute;
437 case SIOCSIFMTU:
438 if ((error = suser(curthread)) != 0)
439 break;
440 if (ifr->ifr_mtu < 576) {
441 error = EINVAL;
442 break;
443 }
444 ifp->if_mtu = ifr->ifr_mtu;
445 break;
446 case SIOCGIFMTU:
447 ifr->ifr_mtu = sc->sc_if.if_mtu;
448 break;
449 case SIOCADDMULTI:
450 case SIOCDELMULTI:
451 if ((error = suser(curthread)) != 0)
452 break;
453 if (ifr == 0) {
454 error = EAFNOSUPPORT;
455 break;
456 }
457 switch (ifr->ifr_addr.sa_family) {
458#ifdef INET
459 case AF_INET:
460 break;
461#endif
462 default:
463 error = EAFNOSUPPORT;
464 break;
465 }
466 break;
467 case GRESPROTO:
468 if ((error = suser(curthread)) != 0)
469 break;
470 sc->g_proto = ifr->ifr_flags;
471 switch (sc->g_proto) {
472 case IPPROTO_GRE:
473 ifp->if_flags |= IFF_LINK0;
474 break;
475 case IPPROTO_MOBILE:
476 ifp->if_flags &= ~IFF_LINK0;
477 break;
478 default:
479 error = EPROTONOSUPPORT;
480 break;
481 }
482 goto recompute;
483 case GREGPROTO:
484 ifr->ifr_flags = sc->g_proto;
485 break;
486 case GRESADDRS:
487 case GRESADDRD:
488 if ((error = suser(curthread)) != 0)
489 break;
490 /*
491 * set tunnel endpoints, compute a less specific route
492 * to the remote end and mark if as up
493 */
494 sa = &ifr->ifr_addr;
495 if (cmd == GRESADDRS)
496 sc->g_src = (satosin(sa))->sin_addr;
497 if (cmd == GRESADDRD)
498 sc->g_dst = (satosin(sa))->sin_addr;
499 recompute:
500#ifdef INET
501 if (sc->encap != NULL) {
502 encap_detach(sc->encap);
503 sc->encap = NULL;
504 }
505#endif
506 if ((sc->g_src.s_addr != INADDR_ANY) &&
507 (sc->g_dst.s_addr != INADDR_ANY)) {
508 bzero(&sp, sizeof(sp));
509 bzero(&sm, sizeof(sm));
510 bzero(&dp, sizeof(dp));
511 bzero(&dm, sizeof(dm));
512 sp.sin_len = sm.sin_len = dp.sin_len = dm.sin_len =
513 sizeof(struct sockaddr_in);
514 sp.sin_family = sm.sin_family = dp.sin_family =
515 dm.sin_family = AF_INET;
516 sp.sin_addr = sc->g_src;
517 dp.sin_addr = sc->g_dst;
518 sm.sin_addr.s_addr = dm.sin_addr.s_addr =
519 INADDR_BROADCAST;
520#ifdef INET
521 sc->encap = encap_attach(AF_INET, sc->g_proto,
522 sintosa(&sp), sintosa(&sm), sintosa(&dp),
523 sintosa(&dm), (sc->g_proto == IPPROTO_GRE) ?
524 &in_gre_protosw : &in_mobile_protosw, sc);
525 if (sc->encap == NULL)
526 printf("%s: unable to attach encap\n",
527 if_name(&sc->sc_if));
528#endif
529 if (sc->route.ro_rt != 0) /* free old route */
530 RTFREE(sc->route.ro_rt);
531 if (gre_compute_route(sc) == 0)
532 ifp->if_flags |= IFF_RUNNING;
533 else
534 ifp->if_flags &= ~IFF_RUNNING;
535 }
536 break;
537 case GREGADDRS:
538 memset(&si, 0, sizeof(si));
539 si.sin_family = AF_INET;
540 si.sin_len = sizeof(struct sockaddr_in);
541 si.sin_addr.s_addr = sc->g_src.s_addr;
542 sa = sintosa(&si);
543 ifr->ifr_addr = *sa;
544 break;
545 case GREGADDRD:
546 memset(&si, 0, sizeof(si));
547 si.sin_family = AF_INET;
548 si.sin_len = sizeof(struct sockaddr_in);
549 si.sin_addr.s_addr = sc->g_dst.s_addr;
550 sa = sintosa(&si);
551 ifr->ifr_addr = *sa;
552 break;
553 case SIOCSIFPHYADDR:
554 if ((error = suser(curthread)) != 0)
555 break;
556 if (aifr->ifra_addr.sin_family != AF_INET ||
557 aifr->ifra_dstaddr.sin_family != AF_INET) {
558 error = EAFNOSUPPORT;
559 break;
560 }
561 if (aifr->ifra_addr.sin_len != sizeof(si) ||
562 aifr->ifra_dstaddr.sin_len != sizeof(si)) {
563 error = EINVAL;
564 break;
565 }
566 sc->g_src = aifr->ifra_addr.sin_addr;
567 sc->g_dst = aifr->ifra_dstaddr.sin_addr;
568 goto recompute;
569 case SIOCSLIFPHYADDR:
570 if ((error = suser(curthread)) != 0)
571 break;
572 if (lifr->addr.ss_family != AF_INET ||
573 lifr->dstaddr.ss_family != AF_INET) {
574 error = EAFNOSUPPORT;
575 break;
576 }
577 if (lifr->addr.ss_len != sizeof(si) ||
578 lifr->dstaddr.ss_len != sizeof(si)) {
579 error = EINVAL;
580 break;
581 }
582 sc->g_src = (satosin((struct sockadrr *)&lifr->addr))->sin_addr;
583 sc->g_dst =
584 (satosin((struct sockadrr *)&lifr->dstaddr))->sin_addr;
585 goto recompute;
586 case SIOCDIFPHYADDR:
587 if ((error = suser(curthread)) != 0)
588 break;
589 sc->g_src.s_addr = INADDR_ANY;
590 sc->g_dst.s_addr = INADDR_ANY;
591 goto recompute;
592 case SIOCGLIFPHYADDR:
593 if (sc->g_src.s_addr == INADDR_ANY ||
594 sc->g_dst.s_addr == INADDR_ANY) {
595 error = EADDRNOTAVAIL;
596 break;
597 }
598 memset(&si, 0, sizeof(si));
599 si.sin_family = AF_INET;
600 si.sin_len = sizeof(struct sockaddr_in);
601 si.sin_addr.s_addr = sc->g_src.s_addr;
602 memcpy(&lifr->addr, &si, sizeof(si));
603 si.sin_addr.s_addr = sc->g_dst.s_addr;
604 memcpy(&lifr->dstaddr, &si, sizeof(si));
605 break;
606 case SIOCGIFPSRCADDR:
607#ifdef INET6
608 case SIOCGIFPSRCADDR_IN6:
609#endif
610 if (sc->g_src.s_addr == INADDR_ANY) {
611 error = EADDRNOTAVAIL;
612 break;
613 }
614 memset(&si, 0, sizeof(si));
615 si.sin_family = AF_INET;
616 si.sin_len = sizeof(struct sockaddr_in);
617 si.sin_addr.s_addr = sc->g_src.s_addr;
618 bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr));
619 break;
620 case SIOCGIFPDSTADDR:
621#ifdef INET6
622 case SIOCGIFPDSTADDR_IN6:
623#endif
624 if (sc->g_dst.s_addr == INADDR_ANY) {
625 error = EADDRNOTAVAIL;
626 break;
627 }
628 memset(&si, 0, sizeof(si));
629 si.sin_family = AF_INET;
630 si.sin_len = sizeof(struct sockaddr_in);
631 si.sin_addr.s_addr = sc->g_dst.s_addr;
632 bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr));
633 break;
634 default:
635 error = EINVAL;
636 break;
637 }
638
639 splx(s);
640 return (error);
641}
642
643/*
644 * computes a route to our destination that is not the one
645 * which would be taken by ip_output(), as this one will loop back to
646 * us. If the interface is p2p as a--->b, then a routing entry exists
647 * If we now send a packet to b (e.g. ping b), this will come down here
648 * gets src=a, dst=b tacked on and would from ip_output() sent back to
649 * if_gre.
650 * Goal here is to compute a route to b that is less specific than
651 * a-->b. We know that this one exists as in normal operation we have
652 * at least a default route which matches.
653 */
654static int
655gre_compute_route(struct gre_softc *sc)
656{
657 struct route *ro;
658 u_int32_t a, b, c;
659
660 ro = &sc->route;
661
662 memset(ro, 0, sizeof(struct route));
663 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst;
664 ro->ro_dst.sa_family = AF_INET;
665 ro->ro_dst.sa_len = sizeof(ro->ro_dst);
666
667 /*
668 * toggle last bit, so our interface is not found, but a less
669 * specific route. I'd rather like to specify a shorter mask,
670 * but this is not possible. Should work though. XXX
671 * there is a simpler way ...
672 */
673 if ((sc->sc_if.if_flags & IFF_LINK1) == 0) {
674 a = ntohl(sc->g_dst.s_addr);
675 b = a & 0x01;
676 c = a & 0xfffffffe;
677 b = b ^ 0x01;
678 a = b | c;
679 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr.s_addr
680 = htonl(a);
681 }
682
683#ifdef DIAGNOSTIC
684 printf("%s: searching for a route to %s", if_name(&sc->sc_if),
685 inet_ntoa(((struct sockaddr_in *)&ro->ro_dst)->sin_addr));
686#endif
687
688 rtalloc(ro);
689
690 /*
691 * check if this returned a route at all and this route is no
692 * recursion to ourself
693 */
694 if (ro->ro_rt == NULL || ro->ro_rt->rt_ifp->if_softc == sc) {
695#ifdef DIAGNOSTIC
696 if (ro->ro_rt == NULL)
697 printf(" - no route found!\n");
698 else
699 printf(" - route loops back to ourself!\n");
700#endif
701 return EADDRNOTAVAIL;
702 }
703
704 /*
705 * now change it back - else ip_output will just drop
706 * the route and search one to this interface ...
707 */
708 if ((sc->sc_if.if_flags & IFF_LINK1) == 0)
709 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst;
710
711#ifdef DIAGNOSTIC
712 printf(", choosing %s with gateway %s", if_name(ro->ro_rt->rt_ifp),
713 inet_ntoa(((struct sockaddr_in *)(ro->ro_rt->rt_gateway))->sin_addr));
714 printf("\n");
715#endif
716
717 return 0;
718}
719
720/*
721 * do a checksum of a buffer - much like in_cksum, which operates on
722 * mbufs.
723 */
724u_int16_t
725gre_in_cksum(u_int16_t *p, u_int len)
726{
727 u_int32_t sum = 0;
728 int nwords = len >> 1;
729
730 while (nwords-- != 0)
731 sum += *p++;
732
733 if (len & 1) {
734 union {
735 u_short w;
736 u_char c[2];
737 } u;
738 u.c[0] = *(u_char *)p;
739 u.c[1] = 0;
740 sum += u.w;
741 }
742
743 /* end-around-carry */
744 sum = (sum >> 16) + (sum & 0xffff);
745 sum += (sum >> 16);
746 return (~sum);
747}
748
749static int
750gremodevent(module_t mod, int type, void *data)
751{
752 struct gre_softc *sc;
753
754 switch (type) {
755 case MOD_LOAD:
756 greattach();
757 break;
758 case MOD_UNLOAD:
759 if_clone_detach(&gre_cloner);
760
761 mtx_lock(&gre_mtx);
762 while ((sc = LIST_FIRST(&gre_softc_list)) != NULL) {
763 LIST_REMOVE(sc, sc_list);
764 mtx_unlock(&gre_mtx);
765 gre_destroy(sc);
766 mtx_lock(&gre_mtx);
767 }
768 mtx_unlock(&gre_mtx);
769 mtx_destroy(&gre_mtx);
770 break;
771 default:
772 return EOPNOTSUPP;
773 }
774 return 0;
775}
776
777static moduledata_t gre_mod = {
778 "if_gre",
779 gremodevent,
780 0
781};
782
783DECLARE_MODULE(if_gre, gre_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
784MODULE_VERSION(if_gre, 1);
|