1/* $NetBSD: if_gre.c,v 1.42 2002/08/14 00:23:27 itojun Exp $ */
| 1/* $NetBSD: if_gre.c,v 1.42 2002/08/14 00:23:27 itojun Exp $ */
|
2/* $FreeBSD: head/sys/net/if_gre.c 109623 2003-01-21 08:56:16Z alfred $ */
| 2/* $FreeBSD: head/sys/net/if_gre.c 111119 2003-02-19 05:47:46Z imp $ */
|
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_ns.h"
52
53#include <sys/param.h>
54#include <sys/kernel.h>
55#include <sys/malloc.h>
56#include <sys/mbuf.h>
57#include <sys/protosw.h>
58#include <sys/socket.h>
59#include <sys/sockio.h>
60#include <sys/sysctl.h>
61#include <sys/systm.h>
62
63#include <net/ethernet.h>
64#include <net/if.h>
65#include <net/if_types.h>
66#include <net/route.h>
67
68#ifdef INET
69#include <netinet/in.h>
70#include <netinet/in_systm.h>
71#include <netinet/in_var.h>
72#include <netinet/ip.h>
73#include <netinet/ip_gre.h>
74#include <netinet/ip_var.h>
75#include <netinet/ip_encap.h>
76#else
77#error "Huh? if_gre without inet?"
78#endif
79
80#include <net/bpf.h>
81
82#include <net/net_osdep.h>
83#include <net/if_gre.h>
84
85/*
86 * It is not easy to calculate the right value for a GRE MTU.
87 * We leave this task to the admin and use the same default that
88 * other vendors use.
89 */
90#define GREMTU 1476
91
92#define GRENAME "gre"
93
94static MALLOC_DEFINE(M_GRE, GRENAME, "Generic Routing Encapsulation");
95
96struct gre_softc_head gre_softc_list;
97
98static int gre_clone_create(struct if_clone *, int);
99static void gre_clone_destroy(struct ifnet *);
100static int gre_ioctl(struct ifnet *, u_long, caddr_t);
101static int gre_output(struct ifnet *, struct mbuf *, struct sockaddr *,
102 struct rtentry *rt);
103
104static struct if_clone gre_cloner =
105 IF_CLONE_INITIALIZER("gre", gre_clone_create, gre_clone_destroy, 0, IF_MAXUNIT);
106
107static int gre_compute_route(struct gre_softc *sc);
108
109static void greattach(void);
110
111#ifdef INET
112extern struct domain inetdomain;
113static const struct protosw in_gre_protosw =
114{ SOCK_RAW, &inetdomain, IPPROTO_GRE, PR_ATOMIC|PR_ADDR,
115 (pr_input_t*)gre_input, (pr_output_t*)rip_output, rip_ctlinput, rip_ctloutput,
116 0,
117 0, 0, 0, 0,
118 &rip_usrreqs
119};
120static const struct protosw in_mobile_protosw =
121{ SOCK_RAW, &inetdomain, IPPROTO_MOBILE, PR_ATOMIC|PR_ADDR,
122 (pr_input_t*)gre_mobile_input, (pr_output_t*)rip_output, rip_ctlinput, rip_ctloutput,
123 0,
124 0, 0, 0, 0,
125 &rip_usrreqs
126};
127#endif
128
129SYSCTL_DECL(_net_link);
130SYSCTL_NODE(_net_link, IFT_OTHER, gre, CTLFLAG_RW, 0,
131 "Generic Routing Encapsulation");
132#ifndef MAX_GRE_NEST
133/*
134 * This macro controls the default upper limitation on nesting of gre tunnels.
135 * Since, setting a large value to this macro with a careless configuration
136 * may introduce system crash, we don't allow any nestings by default.
137 * If you need to configure nested gre tunnels, you can define this macro
138 * in your kernel configuration file. However, if you do so, please be
139 * careful to configure the tunnels so that it won't make a loop.
140 */
141#define MAX_GRE_NEST 1
142#endif
143static int max_gre_nesting = MAX_GRE_NEST;
144SYSCTL_INT(_net_link_gre, OID_AUTO, max_nesting, CTLFLAG_RW,
145 &max_gre_nesting, 0, "Max nested tunnels");
146
147/* ARGSUSED */
148static void
149greattach(void)
150{
151
152 LIST_INIT(&gre_softc_list);
153 if_clone_attach(&gre_cloner);
154}
155
156static int
157gre_clone_create(ifc, unit)
158 struct if_clone *ifc;
159 int unit;
160{
161 struct gre_softc *sc;
162
| 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_ns.h"
52
53#include <sys/param.h>
54#include <sys/kernel.h>
55#include <sys/malloc.h>
56#include <sys/mbuf.h>
57#include <sys/protosw.h>
58#include <sys/socket.h>
59#include <sys/sockio.h>
60#include <sys/sysctl.h>
61#include <sys/systm.h>
62
63#include <net/ethernet.h>
64#include <net/if.h>
65#include <net/if_types.h>
66#include <net/route.h>
67
68#ifdef INET
69#include <netinet/in.h>
70#include <netinet/in_systm.h>
71#include <netinet/in_var.h>
72#include <netinet/ip.h>
73#include <netinet/ip_gre.h>
74#include <netinet/ip_var.h>
75#include <netinet/ip_encap.h>
76#else
77#error "Huh? if_gre without inet?"
78#endif
79
80#include <net/bpf.h>
81
82#include <net/net_osdep.h>
83#include <net/if_gre.h>
84
85/*
86 * It is not easy to calculate the right value for a GRE MTU.
87 * We leave this task to the admin and use the same default that
88 * other vendors use.
89 */
90#define GREMTU 1476
91
92#define GRENAME "gre"
93
94static MALLOC_DEFINE(M_GRE, GRENAME, "Generic Routing Encapsulation");
95
96struct gre_softc_head gre_softc_list;
97
98static int gre_clone_create(struct if_clone *, int);
99static void gre_clone_destroy(struct ifnet *);
100static int gre_ioctl(struct ifnet *, u_long, caddr_t);
101static int gre_output(struct ifnet *, struct mbuf *, struct sockaddr *,
102 struct rtentry *rt);
103
104static struct if_clone gre_cloner =
105 IF_CLONE_INITIALIZER("gre", gre_clone_create, gre_clone_destroy, 0, IF_MAXUNIT);
106
107static int gre_compute_route(struct gre_softc *sc);
108
109static void greattach(void);
110
111#ifdef INET
112extern struct domain inetdomain;
113static const struct protosw in_gre_protosw =
114{ SOCK_RAW, &inetdomain, IPPROTO_GRE, PR_ATOMIC|PR_ADDR,
115 (pr_input_t*)gre_input, (pr_output_t*)rip_output, rip_ctlinput, rip_ctloutput,
116 0,
117 0, 0, 0, 0,
118 &rip_usrreqs
119};
120static const struct protosw in_mobile_protosw =
121{ SOCK_RAW, &inetdomain, IPPROTO_MOBILE, PR_ATOMIC|PR_ADDR,
122 (pr_input_t*)gre_mobile_input, (pr_output_t*)rip_output, rip_ctlinput, rip_ctloutput,
123 0,
124 0, 0, 0, 0,
125 &rip_usrreqs
126};
127#endif
128
129SYSCTL_DECL(_net_link);
130SYSCTL_NODE(_net_link, IFT_OTHER, gre, CTLFLAG_RW, 0,
131 "Generic Routing Encapsulation");
132#ifndef MAX_GRE_NEST
133/*
134 * This macro controls the default upper limitation on nesting of gre tunnels.
135 * Since, setting a large value to this macro with a careless configuration
136 * may introduce system crash, we don't allow any nestings by default.
137 * If you need to configure nested gre tunnels, you can define this macro
138 * in your kernel configuration file. However, if you do so, please be
139 * careful to configure the tunnels so that it won't make a loop.
140 */
141#define MAX_GRE_NEST 1
142#endif
143static int max_gre_nesting = MAX_GRE_NEST;
144SYSCTL_INT(_net_link_gre, OID_AUTO, max_nesting, CTLFLAG_RW,
145 &max_gre_nesting, 0, "Max nested tunnels");
146
147/* ARGSUSED */
148static void
149greattach(void)
150{
151
152 LIST_INIT(&gre_softc_list);
153 if_clone_attach(&gre_cloner);
154}
155
156static int
157gre_clone_create(ifc, unit)
158 struct if_clone *ifc;
159 int unit;
160{
161 struct gre_softc *sc;
162
|
163 sc = malloc(sizeof(struct gre_softc), M_GRE, 0);
| 163 sc = malloc(sizeof(struct gre_softc), M_GRE, M_WAITOK);
|
164 memset(sc, 0, sizeof(struct gre_softc));
165
166 sc->sc_if.if_name = GRENAME;
167 sc->sc_if.if_softc = sc;
168 sc->sc_if.if_unit = unit;
169 sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
170 sc->sc_if.if_type = IFT_OTHER;
171 sc->sc_if.if_addrlen = 0;
172 sc->sc_if.if_hdrlen = 24; /* IP + GRE */
173 sc->sc_if.if_mtu = GREMTU;
174 sc->sc_if.if_flags = IFF_POINTOPOINT|IFF_MULTICAST;
175 sc->sc_if.if_output = gre_output;
176 sc->sc_if.if_ioctl = gre_ioctl;
177 sc->g_dst.s_addr = sc->g_src.s_addr = INADDR_ANY;
178 sc->g_proto = IPPROTO_GRE;
179 sc->sc_if.if_flags |= IFF_LINK0;
180 sc->encap = NULL;
181 sc->called = 0;
182 if_attach(&sc->sc_if);
183 bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int32_t));
184 LIST_INSERT_HEAD(&gre_softc_list, sc, sc_list);
185 return (0);
186}
187
188static void
189gre_clone_destroy(ifp)
190 struct ifnet *ifp;
191{
192 struct gre_softc *sc = ifp->if_softc;
193
194#ifdef INET
195 if (sc->encap != NULL)
196 encap_detach(sc->encap);
197#endif
198 LIST_REMOVE(sc, sc_list);
199 bpfdetach(ifp);
200 if_detach(ifp);
201 free(sc, M_GRE);
202}
203
204/*
205 * The output routine. Takes a packet and encapsulates it in the protocol
206 * given by sc->g_proto. See also RFC 1701 and RFC 2004
207 */
208static int
209gre_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
210 struct rtentry *rt)
211{
212 int error = 0;
213 struct gre_softc *sc = ifp->if_softc;
214 struct greip *gh;
215 struct ip *ip;
216 u_char osrc;
217 u_short etype = 0;
218 struct mobile_h mob_h;
219
220 /*
221 * gre may cause infinite recursion calls when misconfigured.
222 * We'll prevent this by introducing upper limit.
223 */
224 if (++(sc->called) > max_gre_nesting) {
225 printf("%s: gre_output: recursively called too many "
226 "times(%d)\n", if_name(&sc->sc_if), sc->called);
227 m_freem(m);
228 error = EIO; /* is there better errno? */
229 goto end;
230 }
231
232 if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) == 0 ||
233 sc->g_src.s_addr == INADDR_ANY || sc->g_dst.s_addr == INADDR_ANY) {
234 m_freem(m);
235 error = ENETDOWN;
236 goto end;
237 }
238
239 gh = NULL;
240 ip = NULL;
241 osrc = 0;
242
243 if (ifp->if_bpf) {
244 /* see comment of other if_foo.c files */
245 struct mbuf m0;
246 u_int32_t af = dst->sa_family;
247
248 m0.m_next = m;
249 m0.m_len = 4;
250 m0.m_data = (char *)⁡
251
252 BPF_MTAP(ifp, &m0);
253 }
254
255 m->m_flags &= ~(M_BCAST|M_MCAST);
256
257 if (sc->g_proto == IPPROTO_MOBILE) {
258 if (dst->sa_family == AF_INET) {
259 struct mbuf *m0;
260 int msiz;
261
262 ip = mtod(m, struct ip *);
263
264 /*
265 * RFC2004 specifies that fragmented diagrams shouldn't
266 * be encapsulated.
267 */
268 if ((ip->ip_off & IP_MF) != 0) {
269 _IF_DROP(&ifp->if_snd);
270 m_freem(m);
271 error = EINVAL; /* is there better errno? */
272 goto end;
273 }
274 memset(&mob_h, 0, MOB_H_SIZ_L);
275 mob_h.proto = (ip->ip_p) << 8;
276 mob_h.odst = ip->ip_dst.s_addr;
277 ip->ip_dst.s_addr = sc->g_dst.s_addr;
278
279 /*
280 * If the packet comes from our host, we only change
281 * the destination address in the IP header.
282 * Else we also need to save and change the source
283 */
284 if (in_hosteq(ip->ip_src, sc->g_src)) {
285 msiz = MOB_H_SIZ_S;
286 } else {
287 mob_h.proto |= MOB_H_SBIT;
288 mob_h.osrc = ip->ip_src.s_addr;
289 ip->ip_src.s_addr = sc->g_src.s_addr;
290 msiz = MOB_H_SIZ_L;
291 }
292 mob_h.proto = htons(mob_h.proto);
293 mob_h.hcrc = gre_in_cksum((u_short *)&mob_h, msiz);
294
295 if ((m->m_data - msiz) < m->m_pktdat) {
296 /* need new mbuf */
| 164 memset(sc, 0, sizeof(struct gre_softc));
165
166 sc->sc_if.if_name = GRENAME;
167 sc->sc_if.if_softc = sc;
168 sc->sc_if.if_unit = unit;
169 sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
170 sc->sc_if.if_type = IFT_OTHER;
171 sc->sc_if.if_addrlen = 0;
172 sc->sc_if.if_hdrlen = 24; /* IP + GRE */
173 sc->sc_if.if_mtu = GREMTU;
174 sc->sc_if.if_flags = IFF_POINTOPOINT|IFF_MULTICAST;
175 sc->sc_if.if_output = gre_output;
176 sc->sc_if.if_ioctl = gre_ioctl;
177 sc->g_dst.s_addr = sc->g_src.s_addr = INADDR_ANY;
178 sc->g_proto = IPPROTO_GRE;
179 sc->sc_if.if_flags |= IFF_LINK0;
180 sc->encap = NULL;
181 sc->called = 0;
182 if_attach(&sc->sc_if);
183 bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int32_t));
184 LIST_INSERT_HEAD(&gre_softc_list, sc, sc_list);
185 return (0);
186}
187
188static void
189gre_clone_destroy(ifp)
190 struct ifnet *ifp;
191{
192 struct gre_softc *sc = ifp->if_softc;
193
194#ifdef INET
195 if (sc->encap != NULL)
196 encap_detach(sc->encap);
197#endif
198 LIST_REMOVE(sc, sc_list);
199 bpfdetach(ifp);
200 if_detach(ifp);
201 free(sc, M_GRE);
202}
203
204/*
205 * The output routine. Takes a packet and encapsulates it in the protocol
206 * given by sc->g_proto. See also RFC 1701 and RFC 2004
207 */
208static int
209gre_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
210 struct rtentry *rt)
211{
212 int error = 0;
213 struct gre_softc *sc = ifp->if_softc;
214 struct greip *gh;
215 struct ip *ip;
216 u_char osrc;
217 u_short etype = 0;
218 struct mobile_h mob_h;
219
220 /*
221 * gre may cause infinite recursion calls when misconfigured.
222 * We'll prevent this by introducing upper limit.
223 */
224 if (++(sc->called) > max_gre_nesting) {
225 printf("%s: gre_output: recursively called too many "
226 "times(%d)\n", if_name(&sc->sc_if), sc->called);
227 m_freem(m);
228 error = EIO; /* is there better errno? */
229 goto end;
230 }
231
232 if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) == 0 ||
233 sc->g_src.s_addr == INADDR_ANY || sc->g_dst.s_addr == INADDR_ANY) {
234 m_freem(m);
235 error = ENETDOWN;
236 goto end;
237 }
238
239 gh = NULL;
240 ip = NULL;
241 osrc = 0;
242
243 if (ifp->if_bpf) {
244 /* see comment of other if_foo.c files */
245 struct mbuf m0;
246 u_int32_t af = dst->sa_family;
247
248 m0.m_next = m;
249 m0.m_len = 4;
250 m0.m_data = (char *)⁡
251
252 BPF_MTAP(ifp, &m0);
253 }
254
255 m->m_flags &= ~(M_BCAST|M_MCAST);
256
257 if (sc->g_proto == IPPROTO_MOBILE) {
258 if (dst->sa_family == AF_INET) {
259 struct mbuf *m0;
260 int msiz;
261
262 ip = mtod(m, struct ip *);
263
264 /*
265 * RFC2004 specifies that fragmented diagrams shouldn't
266 * be encapsulated.
267 */
268 if ((ip->ip_off & IP_MF) != 0) {
269 _IF_DROP(&ifp->if_snd);
270 m_freem(m);
271 error = EINVAL; /* is there better errno? */
272 goto end;
273 }
274 memset(&mob_h, 0, MOB_H_SIZ_L);
275 mob_h.proto = (ip->ip_p) << 8;
276 mob_h.odst = ip->ip_dst.s_addr;
277 ip->ip_dst.s_addr = sc->g_dst.s_addr;
278
279 /*
280 * If the packet comes from our host, we only change
281 * the destination address in the IP header.
282 * Else we also need to save and change the source
283 */
284 if (in_hosteq(ip->ip_src, sc->g_src)) {
285 msiz = MOB_H_SIZ_S;
286 } else {
287 mob_h.proto |= MOB_H_SBIT;
288 mob_h.osrc = ip->ip_src.s_addr;
289 ip->ip_src.s_addr = sc->g_src.s_addr;
290 msiz = MOB_H_SIZ_L;
291 }
292 mob_h.proto = htons(mob_h.proto);
293 mob_h.hcrc = gre_in_cksum((u_short *)&mob_h, msiz);
294
295 if ((m->m_data - msiz) < m->m_pktdat) {
296 /* need new mbuf */
|
297 MGETHDR(m0, M_NOWAIT, MT_HEADER);
| 297 MGETHDR(m0, M_DONTWAIT, MT_HEADER);
|
298 if (m0 == NULL) {
299 _IF_DROP(&ifp->if_snd);
300 m_freem(m);
301 error = ENOBUFS;
302 goto end;
303 }
304 m0->m_next = m;
305 m->m_data += sizeof(struct ip);
306 m->m_len -= sizeof(struct ip);
307 m0->m_pkthdr.len = m->m_pkthdr.len + msiz;
308 m0->m_len = msiz + sizeof(struct ip);
309 m0->m_data += max_linkhdr;
310 memcpy(mtod(m0, caddr_t), (caddr_t)ip,
311 sizeof(struct ip));
312 m = m0;
313 } else { /* we have some space left in the old one */
314 m->m_data -= msiz;
315 m->m_len += msiz;
316 m->m_pkthdr.len += msiz;
317 bcopy(ip, mtod(m, caddr_t),
318 sizeof(struct ip));
319 }
320 ip = mtod(m, struct ip *);
321 memcpy((caddr_t)(ip + 1), &mob_h, (unsigned)msiz);
322 ip->ip_len = ntohs(ip->ip_len) + msiz;
323 } else { /* AF_INET */
324 _IF_DROP(&ifp->if_snd);
325 m_freem(m);
326 error = EINVAL;
327 goto end;
328 }
329 } else if (sc->g_proto == IPPROTO_GRE) {
330 switch (dst->sa_family) {
331 case AF_INET:
332 ip = mtod(m, struct ip *);
333 etype = ETHERTYPE_IP;
334 break;
335#ifdef NETATALK
336 case AF_APPLETALK:
337 etype = ETHERTYPE_ATALK;
338 break;
339#endif
340#ifdef NS
341 case AF_NS:
342 etype = ETHERTYPE_NS;
343 break;
344#endif
345 default:
346 _IF_DROP(&ifp->if_snd);
347 m_freem(m);
348 error = EAFNOSUPPORT;
349 goto end;
350 }
| 298 if (m0 == NULL) {
299 _IF_DROP(&ifp->if_snd);
300 m_freem(m);
301 error = ENOBUFS;
302 goto end;
303 }
304 m0->m_next = m;
305 m->m_data += sizeof(struct ip);
306 m->m_len -= sizeof(struct ip);
307 m0->m_pkthdr.len = m->m_pkthdr.len + msiz;
308 m0->m_len = msiz + sizeof(struct ip);
309 m0->m_data += max_linkhdr;
310 memcpy(mtod(m0, caddr_t), (caddr_t)ip,
311 sizeof(struct ip));
312 m = m0;
313 } else { /* we have some space left in the old one */
314 m->m_data -= msiz;
315 m->m_len += msiz;
316 m->m_pkthdr.len += msiz;
317 bcopy(ip, mtod(m, caddr_t),
318 sizeof(struct ip));
319 }
320 ip = mtod(m, struct ip *);
321 memcpy((caddr_t)(ip + 1), &mob_h, (unsigned)msiz);
322 ip->ip_len = ntohs(ip->ip_len) + msiz;
323 } else { /* AF_INET */
324 _IF_DROP(&ifp->if_snd);
325 m_freem(m);
326 error = EINVAL;
327 goto end;
328 }
329 } else if (sc->g_proto == IPPROTO_GRE) {
330 switch (dst->sa_family) {
331 case AF_INET:
332 ip = mtod(m, struct ip *);
333 etype = ETHERTYPE_IP;
334 break;
335#ifdef NETATALK
336 case AF_APPLETALK:
337 etype = ETHERTYPE_ATALK;
338 break;
339#endif
340#ifdef NS
341 case AF_NS:
342 etype = ETHERTYPE_NS;
343 break;
344#endif
345 default:
346 _IF_DROP(&ifp->if_snd);
347 m_freem(m);
348 error = EAFNOSUPPORT;
349 goto end;
350 }
|
351 M_PREPEND(m, sizeof(struct greip), M_NOWAIT);
| 351 M_PREPEND(m, sizeof(struct greip), M_DONTWAIT);
|
352 } else {
353 _IF_DROP(&ifp->if_snd);
354 m_freem(m);
355 error = EINVAL;
356 goto end;
357 }
358
359 if (m == NULL) { /* impossible */
360 _IF_DROP(&ifp->if_snd);
361 error = ENOBUFS;
362 goto end;
363 }
364
365 gh = mtod(m, struct greip *);
366 if (sc->g_proto == IPPROTO_GRE) {
367 /* we don't have any GRE flags for now */
368
369 memset((void *)&gh->gi_g, 0, sizeof(struct gre_h));
370 gh->gi_ptype = htons(etype);
371 }
372
373 gh->gi_pr = sc->g_proto;
374 if (sc->g_proto != IPPROTO_MOBILE) {
375 gh->gi_src = sc->g_src;
376 gh->gi_dst = sc->g_dst;
377 ((struct ip*)gh)->ip_hl = (sizeof(struct ip)) >> 2;
378 ((struct ip*)gh)->ip_ttl = GRE_TTL;
379 ((struct ip*)gh)->ip_tos = ip->ip_tos;
380 ((struct ip*)gh)->ip_id = ip->ip_id;
381 gh->gi_len = m->m_pkthdr.len;
382 }
383
384 ifp->if_opackets++;
385 ifp->if_obytes += m->m_pkthdr.len;
386 /* send it off */
387 error = ip_output(m, NULL, &sc->route, 0, NULL, NULL);
388 end:
389 sc->called = 0;
390 if (error)
391 ifp->if_oerrors++;
392 return (error);
393}
394
395static int
396gre_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
397{
398 struct ifreq *ifr = (struct ifreq *)data;
399 struct if_laddrreq *lifr = (struct if_laddrreq *)data;
400 struct in_aliasreq *aifr = (struct in_aliasreq *)data;
401 struct gre_softc *sc = ifp->if_softc;
402 int s;
403 struct sockaddr_in si;
404 struct sockaddr *sa = NULL;
405 int error;
406 struct sockaddr_in sp, sm, dp, dm;
407
408 error = 0;
409
410 s = splnet();
411 switch (cmd) {
412 case SIOCSIFADDR:
413 ifp->if_flags |= IFF_UP;
414 break;
415 case SIOCSIFDSTADDR:
416 break;
417 case SIOCSIFFLAGS:
418 if ((error = suser(curthread)) != 0)
419 break;
420 if ((ifr->ifr_flags & IFF_LINK0) != 0)
421 sc->g_proto = IPPROTO_GRE;
422 else
423 sc->g_proto = IPPROTO_MOBILE;
424 goto recompute;
425 case SIOCSIFMTU:
426 if ((error = suser(curthread)) != 0)
427 break;
428 if (ifr->ifr_mtu < 576) {
429 error = EINVAL;
430 break;
431 }
432 ifp->if_mtu = ifr->ifr_mtu;
433 break;
434 case SIOCGIFMTU:
435 ifr->ifr_mtu = sc->sc_if.if_mtu;
436 break;
437 case SIOCADDMULTI:
438 case SIOCDELMULTI:
439 if ((error = suser(curthread)) != 0)
440 break;
441 if (ifr == 0) {
442 error = EAFNOSUPPORT;
443 break;
444 }
445 switch (ifr->ifr_addr.sa_family) {
446#ifdef INET
447 case AF_INET:
448 break;
449#endif
450 default:
451 error = EAFNOSUPPORT;
452 break;
453 }
454 break;
455 case GRESPROTO:
456 if ((error = suser(curthread)) != 0)
457 break;
458 sc->g_proto = ifr->ifr_flags;
459 switch (sc->g_proto) {
460 case IPPROTO_GRE:
461 ifp->if_flags |= IFF_LINK0;
462 break;
463 case IPPROTO_MOBILE:
464 ifp->if_flags &= ~IFF_LINK0;
465 break;
466 default:
467 error = EPROTONOSUPPORT;
468 break;
469 }
470 goto recompute;
471 case GREGPROTO:
472 ifr->ifr_flags = sc->g_proto;
473 break;
474 case GRESADDRS:
475 case GRESADDRD:
476 if ((error = suser(curthread)) != 0)
477 break;
478 /*
479 * set tunnel endpoints, compute a less specific route
480 * to the remote end and mark if as up
481 */
482 sa = &ifr->ifr_addr;
483 if (cmd == GRESADDRS)
484 sc->g_src = (satosin(sa))->sin_addr;
485 if (cmd == GRESADDRD)
486 sc->g_dst = (satosin(sa))->sin_addr;
487 recompute:
488#ifdef INET
489 if (sc->encap != NULL) {
490 encap_detach(sc->encap);
491 sc->encap = NULL;
492 }
493#endif
494 if ((sc->g_src.s_addr != INADDR_ANY) &&
495 (sc->g_dst.s_addr != INADDR_ANY)) {
496 bzero(&sp, sizeof(sp));
497 bzero(&sm, sizeof(sm));
498 bzero(&dp, sizeof(dp));
499 bzero(&dm, sizeof(dm));
500 sp.sin_len = sm.sin_len = dp.sin_len = dm.sin_len =
501 sizeof(struct sockaddr_in);
502 sp.sin_family = sm.sin_family = dp.sin_family =
503 dm.sin_family = AF_INET;
504 sp.sin_addr = sc->g_src;
505 dp.sin_addr = sc->g_dst;
506 sm.sin_addr.s_addr = dm.sin_addr.s_addr =
507 INADDR_BROADCAST;
508#ifdef INET
509 sc->encap = encap_attach(AF_INET, sc->g_proto,
510 sintosa(&sp), sintosa(&sm), sintosa(&dp),
511 sintosa(&dm), (sc->g_proto == IPPROTO_GRE) ?
512 &in_gre_protosw : &in_mobile_protosw, sc);
513 if (sc->encap == NULL)
514 printf("%s: unable to attach encap\n",
515 if_name(&sc->sc_if));
516#endif
517 if (sc->route.ro_rt != 0) /* free old route */
518 RTFREE(sc->route.ro_rt);
519 if (gre_compute_route(sc) == 0)
520 ifp->if_flags |= IFF_RUNNING;
521 else
522 ifp->if_flags &= ~IFF_RUNNING;
523 }
524 break;
525 case GREGADDRS:
526 memset(&si, 0, sizeof(si));
527 si.sin_family = AF_INET;
528 si.sin_len = sizeof(struct sockaddr_in);
529 si.sin_addr.s_addr = sc->g_src.s_addr;
530 sa = sintosa(&si);
531 ifr->ifr_addr = *sa;
532 break;
533 case GREGADDRD:
534 memset(&si, 0, sizeof(si));
535 si.sin_family = AF_INET;
536 si.sin_len = sizeof(struct sockaddr_in);
537 si.sin_addr.s_addr = sc->g_dst.s_addr;
538 sa = sintosa(&si);
539 ifr->ifr_addr = *sa;
540 break;
541 case SIOCSIFPHYADDR:
542 if ((error = suser(curthread)) != 0)
543 break;
544 if (aifr->ifra_addr.sin_family != AF_INET ||
545 aifr->ifra_dstaddr.sin_family != AF_INET) {
546 error = EAFNOSUPPORT;
547 break;
548 }
549 if (aifr->ifra_addr.sin_len != sizeof(si) ||
550 aifr->ifra_dstaddr.sin_len != sizeof(si)) {
551 error = EINVAL;
552 break;
553 }
554 sc->g_src = aifr->ifra_addr.sin_addr;
555 sc->g_dst = aifr->ifra_dstaddr.sin_addr;
556 goto recompute;
557 case SIOCSLIFPHYADDR:
558 if ((error = suser(curthread)) != 0)
559 break;
560 if (lifr->addr.ss_family != AF_INET ||
561 lifr->dstaddr.ss_family != AF_INET) {
562 error = EAFNOSUPPORT;
563 break;
564 }
565 if (lifr->addr.ss_len != sizeof(si) ||
566 lifr->dstaddr.ss_len != sizeof(si)) {
567 error = EINVAL;
568 break;
569 }
570 sc->g_src = (satosin((struct sockadrr *)&lifr->addr))->sin_addr;
571 sc->g_dst =
572 (satosin((struct sockadrr *)&lifr->dstaddr))->sin_addr;
573 goto recompute;
574 case SIOCDIFPHYADDR:
575 if ((error = suser(curthread)) != 0)
576 break;
577 sc->g_src.s_addr = INADDR_ANY;
578 sc->g_dst.s_addr = INADDR_ANY;
579 goto recompute;
580 case SIOCGLIFPHYADDR:
581 if (sc->g_src.s_addr == INADDR_ANY ||
582 sc->g_dst.s_addr == INADDR_ANY) {
583 error = EADDRNOTAVAIL;
584 break;
585 }
586 memset(&si, 0, sizeof(si));
587 si.sin_family = AF_INET;
588 si.sin_len = sizeof(struct sockaddr_in);
589 si.sin_addr.s_addr = sc->g_src.s_addr;
590 memcpy(&lifr->addr, &si, sizeof(si));
591 si.sin_addr.s_addr = sc->g_dst.s_addr;
592 memcpy(&lifr->dstaddr, &si, sizeof(si));
593 break;
594 case SIOCGIFPSRCADDR:
595 if (sc->g_src.s_addr == INADDR_ANY) {
596 error = EADDRNOTAVAIL;
597 break;
598 }
599 memset(&si, 0, sizeof(si));
600 si.sin_family = AF_INET;
601 si.sin_len = sizeof(struct sockaddr_in);
602 si.sin_addr.s_addr = sc->g_src.s_addr;
603 bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr));
604 break;
605 case SIOCGIFPDSTADDR:
606 if (sc->g_dst.s_addr == INADDR_ANY) {
607 error = EADDRNOTAVAIL;
608 break;
609 }
610 memset(&si, 0, sizeof(si));
611 si.sin_family = AF_INET;
612 si.sin_len = sizeof(struct sockaddr_in);
613 si.sin_addr.s_addr = sc->g_dst.s_addr;
614 bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr));
615 break;
616 default:
617 error = EINVAL;
618 break;
619 }
620
621 splx(s);
622 return (error);
623}
624
625/*
626 * computes a route to our destination that is not the one
627 * which would be taken by ip_output(), as this one will loop back to
628 * us. If the interface is p2p as a--->b, then a routing entry exists
629 * If we now send a packet to b (e.g. ping b), this will come down here
630 * gets src=a, dst=b tacked on and would from ip_ouput() sent back to
631 * if_gre.
632 * Goal here is to compute a route to b that is less specific than
633 * a-->b. We know that this one exists as in normal operation we have
634 * at least a default route which matches.
635 */
636static int
637gre_compute_route(struct gre_softc *sc)
638{
639 struct route *ro;
640 u_int32_t a, b, c;
641
642 ro = &sc->route;
643
644 memset(ro, 0, sizeof(struct route));
645 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst;
646 ro->ro_dst.sa_family = AF_INET;
647 ro->ro_dst.sa_len = sizeof(ro->ro_dst);
648
649 /*
650 * toggle last bit, so our interface is not found, but a less
651 * specific route. I'd rather like to specify a shorter mask,
652 * but this is not possible. Should work though. XXX
653 * there is a simpler way ...
654 */
655 if ((sc->sc_if.if_flags & IFF_LINK1) == 0) {
656 a = ntohl(sc->g_dst.s_addr);
657 b = a & 0x01;
658 c = a & 0xfffffffe;
659 b = b ^ 0x01;
660 a = b | c;
661 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr.s_addr
662 = htonl(a);
663 }
664
665#ifdef DIAGNOSTIC
666 printf("%s: searching a route to %s", if_name(&sc->sc_if),
667 inet_ntoa(((struct sockaddr_in *)&ro->ro_dst)->sin_addr));
668#endif
669
670 rtalloc(ro);
671
672 /*
673 * check if this returned a route at all and this route is no
674 * recursion to ourself
675 */
676 if (ro->ro_rt == NULL || ro->ro_rt->rt_ifp->if_softc == sc) {
677#ifdef DIAGNOSTIC
678 if (ro->ro_rt == NULL)
679 printf(" - no route found!\n");
680 else
681 printf(" - route loops back to ourself!\n");
682#endif
683 return EADDRNOTAVAIL;
684 }
685
686 /*
687 * now change it back - else ip_output will just drop
688 * the route and search one to this interface ...
689 */
690 if ((sc->sc_if.if_flags & IFF_LINK1) == 0)
691 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst;
692
693#ifdef DIAGNOSTIC
694 printf(", choosing %s with gateway %s", if_name(ro->ro_rt->rt_ifp),
695 inet_ntoa(((struct sockaddr_in *)(ro->ro_rt->rt_gateway))->sin_addr));
696 printf("\n");
697#endif
698
699 return 0;
700}
701
702/*
703 * do a checksum of a buffer - much like in_cksum, which operates on
704 * mbufs.
705 */
706u_short
707gre_in_cksum(u_short *p, u_int len)
708{
709 u_int sum = 0;
710 int nwords = len >> 1;
711
712 while (nwords-- != 0)
713 sum += *p++;
714
715 if (len & 1) {
716 union {
717 u_short w;
718 u_char c[2];
719 } u;
720 u.c[0] = *(u_char *)p;
721 u.c[1] = 0;
722 sum += u.w;
723 }
724
725 /* end-around-carry */
726 sum = (sum >> 16) + (sum & 0xffff);
727 sum += (sum >> 16);
728 return (~sum);
729}
730
731static int
732gremodevent(module_t mod, int type, void *data)
733{
734
735 switch (type) {
736 case MOD_LOAD:
737 greattach();
738 break;
739 case MOD_UNLOAD:
740 if_clone_detach(&gre_cloner);
741
742 while (!LIST_EMPTY(&gre_softc_list))
743 gre_clone_destroy(&LIST_FIRST(&gre_softc_list)->sc_if);
744 break;
745 }
746 return 0;
747}
748
749static moduledata_t gre_mod = {
750 "if_gre",
751 gremodevent,
752 0
753};
754
755DECLARE_MODULE(if_gre, gre_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
756MODULE_VERSION(if_gre, 1);
| 352 } else {
353 _IF_DROP(&ifp->if_snd);
354 m_freem(m);
355 error = EINVAL;
356 goto end;
357 }
358
359 if (m == NULL) { /* impossible */
360 _IF_DROP(&ifp->if_snd);
361 error = ENOBUFS;
362 goto end;
363 }
364
365 gh = mtod(m, struct greip *);
366 if (sc->g_proto == IPPROTO_GRE) {
367 /* we don't have any GRE flags for now */
368
369 memset((void *)&gh->gi_g, 0, sizeof(struct gre_h));
370 gh->gi_ptype = htons(etype);
371 }
372
373 gh->gi_pr = sc->g_proto;
374 if (sc->g_proto != IPPROTO_MOBILE) {
375 gh->gi_src = sc->g_src;
376 gh->gi_dst = sc->g_dst;
377 ((struct ip*)gh)->ip_hl = (sizeof(struct ip)) >> 2;
378 ((struct ip*)gh)->ip_ttl = GRE_TTL;
379 ((struct ip*)gh)->ip_tos = ip->ip_tos;
380 ((struct ip*)gh)->ip_id = ip->ip_id;
381 gh->gi_len = m->m_pkthdr.len;
382 }
383
384 ifp->if_opackets++;
385 ifp->if_obytes += m->m_pkthdr.len;
386 /* send it off */
387 error = ip_output(m, NULL, &sc->route, 0, NULL, NULL);
388 end:
389 sc->called = 0;
390 if (error)
391 ifp->if_oerrors++;
392 return (error);
393}
394
395static int
396gre_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
397{
398 struct ifreq *ifr = (struct ifreq *)data;
399 struct if_laddrreq *lifr = (struct if_laddrreq *)data;
400 struct in_aliasreq *aifr = (struct in_aliasreq *)data;
401 struct gre_softc *sc = ifp->if_softc;
402 int s;
403 struct sockaddr_in si;
404 struct sockaddr *sa = NULL;
405 int error;
406 struct sockaddr_in sp, sm, dp, dm;
407
408 error = 0;
409
410 s = splnet();
411 switch (cmd) {
412 case SIOCSIFADDR:
413 ifp->if_flags |= IFF_UP;
414 break;
415 case SIOCSIFDSTADDR:
416 break;
417 case SIOCSIFFLAGS:
418 if ((error = suser(curthread)) != 0)
419 break;
420 if ((ifr->ifr_flags & IFF_LINK0) != 0)
421 sc->g_proto = IPPROTO_GRE;
422 else
423 sc->g_proto = IPPROTO_MOBILE;
424 goto recompute;
425 case SIOCSIFMTU:
426 if ((error = suser(curthread)) != 0)
427 break;
428 if (ifr->ifr_mtu < 576) {
429 error = EINVAL;
430 break;
431 }
432 ifp->if_mtu = ifr->ifr_mtu;
433 break;
434 case SIOCGIFMTU:
435 ifr->ifr_mtu = sc->sc_if.if_mtu;
436 break;
437 case SIOCADDMULTI:
438 case SIOCDELMULTI:
439 if ((error = suser(curthread)) != 0)
440 break;
441 if (ifr == 0) {
442 error = EAFNOSUPPORT;
443 break;
444 }
445 switch (ifr->ifr_addr.sa_family) {
446#ifdef INET
447 case AF_INET:
448 break;
449#endif
450 default:
451 error = EAFNOSUPPORT;
452 break;
453 }
454 break;
455 case GRESPROTO:
456 if ((error = suser(curthread)) != 0)
457 break;
458 sc->g_proto = ifr->ifr_flags;
459 switch (sc->g_proto) {
460 case IPPROTO_GRE:
461 ifp->if_flags |= IFF_LINK0;
462 break;
463 case IPPROTO_MOBILE:
464 ifp->if_flags &= ~IFF_LINK0;
465 break;
466 default:
467 error = EPROTONOSUPPORT;
468 break;
469 }
470 goto recompute;
471 case GREGPROTO:
472 ifr->ifr_flags = sc->g_proto;
473 break;
474 case GRESADDRS:
475 case GRESADDRD:
476 if ((error = suser(curthread)) != 0)
477 break;
478 /*
479 * set tunnel endpoints, compute a less specific route
480 * to the remote end and mark if as up
481 */
482 sa = &ifr->ifr_addr;
483 if (cmd == GRESADDRS)
484 sc->g_src = (satosin(sa))->sin_addr;
485 if (cmd == GRESADDRD)
486 sc->g_dst = (satosin(sa))->sin_addr;
487 recompute:
488#ifdef INET
489 if (sc->encap != NULL) {
490 encap_detach(sc->encap);
491 sc->encap = NULL;
492 }
493#endif
494 if ((sc->g_src.s_addr != INADDR_ANY) &&
495 (sc->g_dst.s_addr != INADDR_ANY)) {
496 bzero(&sp, sizeof(sp));
497 bzero(&sm, sizeof(sm));
498 bzero(&dp, sizeof(dp));
499 bzero(&dm, sizeof(dm));
500 sp.sin_len = sm.sin_len = dp.sin_len = dm.sin_len =
501 sizeof(struct sockaddr_in);
502 sp.sin_family = sm.sin_family = dp.sin_family =
503 dm.sin_family = AF_INET;
504 sp.sin_addr = sc->g_src;
505 dp.sin_addr = sc->g_dst;
506 sm.sin_addr.s_addr = dm.sin_addr.s_addr =
507 INADDR_BROADCAST;
508#ifdef INET
509 sc->encap = encap_attach(AF_INET, sc->g_proto,
510 sintosa(&sp), sintosa(&sm), sintosa(&dp),
511 sintosa(&dm), (sc->g_proto == IPPROTO_GRE) ?
512 &in_gre_protosw : &in_mobile_protosw, sc);
513 if (sc->encap == NULL)
514 printf("%s: unable to attach encap\n",
515 if_name(&sc->sc_if));
516#endif
517 if (sc->route.ro_rt != 0) /* free old route */
518 RTFREE(sc->route.ro_rt);
519 if (gre_compute_route(sc) == 0)
520 ifp->if_flags |= IFF_RUNNING;
521 else
522 ifp->if_flags &= ~IFF_RUNNING;
523 }
524 break;
525 case GREGADDRS:
526 memset(&si, 0, sizeof(si));
527 si.sin_family = AF_INET;
528 si.sin_len = sizeof(struct sockaddr_in);
529 si.sin_addr.s_addr = sc->g_src.s_addr;
530 sa = sintosa(&si);
531 ifr->ifr_addr = *sa;
532 break;
533 case GREGADDRD:
534 memset(&si, 0, sizeof(si));
535 si.sin_family = AF_INET;
536 si.sin_len = sizeof(struct sockaddr_in);
537 si.sin_addr.s_addr = sc->g_dst.s_addr;
538 sa = sintosa(&si);
539 ifr->ifr_addr = *sa;
540 break;
541 case SIOCSIFPHYADDR:
542 if ((error = suser(curthread)) != 0)
543 break;
544 if (aifr->ifra_addr.sin_family != AF_INET ||
545 aifr->ifra_dstaddr.sin_family != AF_INET) {
546 error = EAFNOSUPPORT;
547 break;
548 }
549 if (aifr->ifra_addr.sin_len != sizeof(si) ||
550 aifr->ifra_dstaddr.sin_len != sizeof(si)) {
551 error = EINVAL;
552 break;
553 }
554 sc->g_src = aifr->ifra_addr.sin_addr;
555 sc->g_dst = aifr->ifra_dstaddr.sin_addr;
556 goto recompute;
557 case SIOCSLIFPHYADDR:
558 if ((error = suser(curthread)) != 0)
559 break;
560 if (lifr->addr.ss_family != AF_INET ||
561 lifr->dstaddr.ss_family != AF_INET) {
562 error = EAFNOSUPPORT;
563 break;
564 }
565 if (lifr->addr.ss_len != sizeof(si) ||
566 lifr->dstaddr.ss_len != sizeof(si)) {
567 error = EINVAL;
568 break;
569 }
570 sc->g_src = (satosin((struct sockadrr *)&lifr->addr))->sin_addr;
571 sc->g_dst =
572 (satosin((struct sockadrr *)&lifr->dstaddr))->sin_addr;
573 goto recompute;
574 case SIOCDIFPHYADDR:
575 if ((error = suser(curthread)) != 0)
576 break;
577 sc->g_src.s_addr = INADDR_ANY;
578 sc->g_dst.s_addr = INADDR_ANY;
579 goto recompute;
580 case SIOCGLIFPHYADDR:
581 if (sc->g_src.s_addr == INADDR_ANY ||
582 sc->g_dst.s_addr == INADDR_ANY) {
583 error = EADDRNOTAVAIL;
584 break;
585 }
586 memset(&si, 0, sizeof(si));
587 si.sin_family = AF_INET;
588 si.sin_len = sizeof(struct sockaddr_in);
589 si.sin_addr.s_addr = sc->g_src.s_addr;
590 memcpy(&lifr->addr, &si, sizeof(si));
591 si.sin_addr.s_addr = sc->g_dst.s_addr;
592 memcpy(&lifr->dstaddr, &si, sizeof(si));
593 break;
594 case SIOCGIFPSRCADDR:
595 if (sc->g_src.s_addr == INADDR_ANY) {
596 error = EADDRNOTAVAIL;
597 break;
598 }
599 memset(&si, 0, sizeof(si));
600 si.sin_family = AF_INET;
601 si.sin_len = sizeof(struct sockaddr_in);
602 si.sin_addr.s_addr = sc->g_src.s_addr;
603 bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr));
604 break;
605 case SIOCGIFPDSTADDR:
606 if (sc->g_dst.s_addr == INADDR_ANY) {
607 error = EADDRNOTAVAIL;
608 break;
609 }
610 memset(&si, 0, sizeof(si));
611 si.sin_family = AF_INET;
612 si.sin_len = sizeof(struct sockaddr_in);
613 si.sin_addr.s_addr = sc->g_dst.s_addr;
614 bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr));
615 break;
616 default:
617 error = EINVAL;
618 break;
619 }
620
621 splx(s);
622 return (error);
623}
624
625/*
626 * computes a route to our destination that is not the one
627 * which would be taken by ip_output(), as this one will loop back to
628 * us. If the interface is p2p as a--->b, then a routing entry exists
629 * If we now send a packet to b (e.g. ping b), this will come down here
630 * gets src=a, dst=b tacked on and would from ip_ouput() sent back to
631 * if_gre.
632 * Goal here is to compute a route to b that is less specific than
633 * a-->b. We know that this one exists as in normal operation we have
634 * at least a default route which matches.
635 */
636static int
637gre_compute_route(struct gre_softc *sc)
638{
639 struct route *ro;
640 u_int32_t a, b, c;
641
642 ro = &sc->route;
643
644 memset(ro, 0, sizeof(struct route));
645 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst;
646 ro->ro_dst.sa_family = AF_INET;
647 ro->ro_dst.sa_len = sizeof(ro->ro_dst);
648
649 /*
650 * toggle last bit, so our interface is not found, but a less
651 * specific route. I'd rather like to specify a shorter mask,
652 * but this is not possible. Should work though. XXX
653 * there is a simpler way ...
654 */
655 if ((sc->sc_if.if_flags & IFF_LINK1) == 0) {
656 a = ntohl(sc->g_dst.s_addr);
657 b = a & 0x01;
658 c = a & 0xfffffffe;
659 b = b ^ 0x01;
660 a = b | c;
661 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr.s_addr
662 = htonl(a);
663 }
664
665#ifdef DIAGNOSTIC
666 printf("%s: searching a route to %s", if_name(&sc->sc_if),
667 inet_ntoa(((struct sockaddr_in *)&ro->ro_dst)->sin_addr));
668#endif
669
670 rtalloc(ro);
671
672 /*
673 * check if this returned a route at all and this route is no
674 * recursion to ourself
675 */
676 if (ro->ro_rt == NULL || ro->ro_rt->rt_ifp->if_softc == sc) {
677#ifdef DIAGNOSTIC
678 if (ro->ro_rt == NULL)
679 printf(" - no route found!\n");
680 else
681 printf(" - route loops back to ourself!\n");
682#endif
683 return EADDRNOTAVAIL;
684 }
685
686 /*
687 * now change it back - else ip_output will just drop
688 * the route and search one to this interface ...
689 */
690 if ((sc->sc_if.if_flags & IFF_LINK1) == 0)
691 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst;
692
693#ifdef DIAGNOSTIC
694 printf(", choosing %s with gateway %s", if_name(ro->ro_rt->rt_ifp),
695 inet_ntoa(((struct sockaddr_in *)(ro->ro_rt->rt_gateway))->sin_addr));
696 printf("\n");
697#endif
698
699 return 0;
700}
701
702/*
703 * do a checksum of a buffer - much like in_cksum, which operates on
704 * mbufs.
705 */
706u_short
707gre_in_cksum(u_short *p, u_int len)
708{
709 u_int sum = 0;
710 int nwords = len >> 1;
711
712 while (nwords-- != 0)
713 sum += *p++;
714
715 if (len & 1) {
716 union {
717 u_short w;
718 u_char c[2];
719 } u;
720 u.c[0] = *(u_char *)p;
721 u.c[1] = 0;
722 sum += u.w;
723 }
724
725 /* end-around-carry */
726 sum = (sum >> 16) + (sum & 0xffff);
727 sum += (sum >> 16);
728 return (~sum);
729}
730
731static int
732gremodevent(module_t mod, int type, void *data)
733{
734
735 switch (type) {
736 case MOD_LOAD:
737 greattach();
738 break;
739 case MOD_UNLOAD:
740 if_clone_detach(&gre_cloner);
741
742 while (!LIST_EMPTY(&gre_softc_list))
743 gre_clone_destroy(&LIST_FIRST(&gre_softc_list)->sc_if);
744 break;
745 }
746 return 0;
747}
748
749static moduledata_t gre_mod = {
750 "if_gre",
751 gremodevent,
752 0
753};
754
755DECLARE_MODULE(if_gre, gre_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
756MODULE_VERSION(if_gre, 1);
|