1/* $NetBSD: ip_gre.c,v 1.29 2003/09/05 23:02:43 itojun Exp $ */
| 1/* $NetBSD: ip_gre.c,v 1.29 2003/09/05 23:02:43 itojun Exp $ */
|
2/* $FreeBSD: head/sys/netinet/ip_gre.c 147256 2005-06-10 16:49:24Z brooks $ */
| 2/* $FreeBSD: head/sys/netinet/ip_gre.c 148613 2005-08-01 08:14:21Z bz $ */
|
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 *
| 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 * IPv6-over-GRE contributed by Gert Doering <gert@greenie.muc.de>
12 *
|
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 * deencapsulate tunneled packets and send them on
42 * output half is in net/if_gre.[ch]
43 * This currently handles IPPROTO_GRE, IPPROTO_MOBILE
44 */
45
46#include "opt_inet.h"
47#include "opt_atalk.h"
| 13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. All advertising materials mentioning features or use of this software
22 * must display the following acknowledgement:
23 * This product includes software developed by the NetBSD
24 * Foundation, Inc. and its contributors.
25 * 4. Neither the name of The NetBSD Foundation nor the names of its
26 * contributors may be used to endorse or promote products derived
27 * from this software without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
30 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
31 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
32 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
33 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
34 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
35 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
36 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
37 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
38 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
39 * POSSIBILITY OF SUCH DAMAGE.
40 */
41
42/*
43 * deencapsulate tunneled packets and send them on
44 * output half is in net/if_gre.[ch]
45 * This currently handles IPPROTO_GRE, IPPROTO_MOBILE
46 */
47
48#include "opt_inet.h"
49#include "opt_atalk.h"
|
| 50#include "opt_inet6.h"
|
48
49#include <sys/param.h>
50#include <sys/systm.h>
51#include <sys/mbuf.h>
52#include <sys/socket.h>
53#include <sys/socketvar.h>
54#include <sys/protosw.h>
55#include <sys/errno.h>
56#include <sys/time.h>
57#include <sys/kernel.h>
58#include <sys/syslog.h>
59#include <net/bpf.h>
60#include <net/ethernet.h>
61#include <net/if.h>
62#include <net/netisr.h>
63#include <net/route.h>
64#include <net/raw_cb.h>
65
66#ifdef INET
67#include <netinet/in.h>
68#include <netinet/in_var.h>
69#include <netinet/in_systm.h>
70#include <netinet/ip.h>
71#include <netinet/ip_var.h>
72#include <netinet/ip_gre.h>
73#include <machine/in_cksum.h>
74#else
75#error ip_gre input without IP?
76#endif
77
78#ifdef NETATALK
79#include <netatalk/at.h>
80#include <netatalk/at_var.h>
81#include <netatalk/at_extern.h>
82#endif
83
84/* Needs IP headers. */
85#include <net/if_gre.h>
86
87#include <machine/stdarg.h>
88
89#if 1
90void gre_inet_ntoa(struct in_addr in); /* XXX */
91#endif
92
93static struct gre_softc *gre_lookup(struct mbuf *, u_int8_t);
94
95static int gre_input2(struct mbuf *, int, u_char);
96
97/*
98 * De-encapsulate a packet and feed it back through ip input (this
99 * routine is called whenever IP gets a packet with proto type
100 * IPPROTO_GRE and a local destination address).
101 * This really is simple
102 */
103void
104#if __STDC__
105gre_input(struct mbuf *m, ...)
106#else
107gre_input(m, va_alist)
108 struct mbuf *m;
109 va_dcl
110#endif
111{
112 int off, ret, proto;
113 va_list ap;
114
115 va_start(ap, m);
116 off = va_arg(ap, int);
117 va_end(ap);
118 proto = (mtod(m, struct ip *))->ip_p;
119
120 ret = gre_input2(m, off, proto);
121 /*
122 * ret == 0 : packet not processed, meaning that
123 * no matching tunnel that is up is found.
124 * we inject it to raw ip socket to see if anyone picks it up.
125 */
126 if (ret == 0)
127 rip_input(m, off);
128}
129
130/*
131 * decapsulate.
132 * Does the real work and is called from gre_input() (above)
133 * returns 0 if packet is not yet processed
134 * and 1 if it needs no further processing
135 * proto is the protocol number of the "calling" foo_input()
136 * routine.
137 */
138static int
139gre_input2(struct mbuf *m ,int hlen, u_char proto)
140{
141 struct greip *gip;
142 int isr;
143 struct gre_softc *sc;
144 u_int16_t flags;
| 51
52#include <sys/param.h>
53#include <sys/systm.h>
54#include <sys/mbuf.h>
55#include <sys/socket.h>
56#include <sys/socketvar.h>
57#include <sys/protosw.h>
58#include <sys/errno.h>
59#include <sys/time.h>
60#include <sys/kernel.h>
61#include <sys/syslog.h>
62#include <net/bpf.h>
63#include <net/ethernet.h>
64#include <net/if.h>
65#include <net/netisr.h>
66#include <net/route.h>
67#include <net/raw_cb.h>
68
69#ifdef INET
70#include <netinet/in.h>
71#include <netinet/in_var.h>
72#include <netinet/in_systm.h>
73#include <netinet/ip.h>
74#include <netinet/ip_var.h>
75#include <netinet/ip_gre.h>
76#include <machine/in_cksum.h>
77#else
78#error ip_gre input without IP?
79#endif
80
81#ifdef NETATALK
82#include <netatalk/at.h>
83#include <netatalk/at_var.h>
84#include <netatalk/at_extern.h>
85#endif
86
87/* Needs IP headers. */
88#include <net/if_gre.h>
89
90#include <machine/stdarg.h>
91
92#if 1
93void gre_inet_ntoa(struct in_addr in); /* XXX */
94#endif
95
96static struct gre_softc *gre_lookup(struct mbuf *, u_int8_t);
97
98static int gre_input2(struct mbuf *, int, u_char);
99
100/*
101 * De-encapsulate a packet and feed it back through ip input (this
102 * routine is called whenever IP gets a packet with proto type
103 * IPPROTO_GRE and a local destination address).
104 * This really is simple
105 */
106void
107#if __STDC__
108gre_input(struct mbuf *m, ...)
109#else
110gre_input(m, va_alist)
111 struct mbuf *m;
112 va_dcl
113#endif
114{
115 int off, ret, proto;
116 va_list ap;
117
118 va_start(ap, m);
119 off = va_arg(ap, int);
120 va_end(ap);
121 proto = (mtod(m, struct ip *))->ip_p;
122
123 ret = gre_input2(m, off, proto);
124 /*
125 * ret == 0 : packet not processed, meaning that
126 * no matching tunnel that is up is found.
127 * we inject it to raw ip socket to see if anyone picks it up.
128 */
129 if (ret == 0)
130 rip_input(m, off);
131}
132
133/*
134 * decapsulate.
135 * Does the real work and is called from gre_input() (above)
136 * returns 0 if packet is not yet processed
137 * and 1 if it needs no further processing
138 * proto is the protocol number of the "calling" foo_input()
139 * routine.
140 */
141static int
142gre_input2(struct mbuf *m ,int hlen, u_char proto)
143{
144 struct greip *gip;
145 int isr;
146 struct gre_softc *sc;
147 u_int16_t flags;
|
| 148 u_int32_t af;
|
145
146 if ((sc = gre_lookup(m, proto)) == NULL) {
147 /* No matching tunnel or tunnel is down. */
148 return (0);
149 }
150
151 if (m->m_len < sizeof(*gip)) {
152 m = m_pullup(m, sizeof(*gip));
153 if (m == NULL)
154 return (ENOBUFS);
155 }
156 gip = mtod(m, struct greip *);
157
158 GRE2IFP(sc)->if_ipackets++;
159 GRE2IFP(sc)->if_ibytes += m->m_pkthdr.len;
160
161 switch (proto) {
162 case IPPROTO_GRE:
163 hlen += sizeof(struct gre_h);
164
165 /* process GRE flags as packet can be of variable len */
166 flags = ntohs(gip->gi_flags);
167
168 /* Checksum & Offset are present */
169 if ((flags & GRE_CP) | (flags & GRE_RP))
170 hlen += 4;
171 /* We don't support routing fields (variable length) */
172 if (flags & GRE_RP)
173 return (0);
174 if (flags & GRE_KP)
175 hlen += 4;
176 if (flags & GRE_SP)
177 hlen += 4;
178
179 switch (ntohs(gip->gi_ptype)) { /* ethertypes */
180 case WCCP_PROTOCOL_TYPE:
181 if (sc->wccp_ver == WCCP_V2)
182 hlen += 4;
183 /* FALLTHROUGH */
184 case ETHERTYPE_IP: /* shouldn't need a schednetisr(), */
185 isr = NETISR_IP;/* as we are in ip_input */
| 149
150 if ((sc = gre_lookup(m, proto)) == NULL) {
151 /* No matching tunnel or tunnel is down. */
152 return (0);
153 }
154
155 if (m->m_len < sizeof(*gip)) {
156 m = m_pullup(m, sizeof(*gip));
157 if (m == NULL)
158 return (ENOBUFS);
159 }
160 gip = mtod(m, struct greip *);
161
162 GRE2IFP(sc)->if_ipackets++;
163 GRE2IFP(sc)->if_ibytes += m->m_pkthdr.len;
164
165 switch (proto) {
166 case IPPROTO_GRE:
167 hlen += sizeof(struct gre_h);
168
169 /* process GRE flags as packet can be of variable len */
170 flags = ntohs(gip->gi_flags);
171
172 /* Checksum & Offset are present */
173 if ((flags & GRE_CP) | (flags & GRE_RP))
174 hlen += 4;
175 /* We don't support routing fields (variable length) */
176 if (flags & GRE_RP)
177 return (0);
178 if (flags & GRE_KP)
179 hlen += 4;
180 if (flags & GRE_SP)
181 hlen += 4;
182
183 switch (ntohs(gip->gi_ptype)) { /* ethertypes */
184 case WCCP_PROTOCOL_TYPE:
185 if (sc->wccp_ver == WCCP_V2)
186 hlen += 4;
187 /* FALLTHROUGH */
188 case ETHERTYPE_IP: /* shouldn't need a schednetisr(), */
189 isr = NETISR_IP;/* as we are in ip_input */
|
| 190 af = AF_INET;
|
186 break;
| 191 break;
|
| 192#ifdef INET6
193 case ETHERTYPE_IPV6:
194 isr = NETISR_IPV6;
195 af = AF_INET6;
196 break;
197#endif
|
187#ifdef NETATALK
188 case ETHERTYPE_ATALK:
189 isr = NETISR_ATALK1;
| 198#ifdef NETATALK
199 case ETHERTYPE_ATALK:
200 isr = NETISR_ATALK1;
|
| 201 af = AF_APPLETALK;
|
190 break;
191#endif
| 202 break;
203#endif
|
192 case ETHERTYPE_IPV6:
193 /* FALLTHROUGH */
| |
194 default: /* others not yet supported */
195 return (0);
196 }
197 break;
198 default:
199 /* others not yet supported */
200 return (0);
201 }
202
203 if (hlen > m->m_pkthdr.len) {
204 m_freem(m);
205 return (EINVAL);
206 }
207 /* Unlike NetBSD, in FreeBSD m_adj() adjusts m->m_pkthdr.len as well */
208 m_adj(m, hlen);
209
210 if (GRE2IFP(sc)->if_bpf) {
| 204 default: /* others not yet supported */
205 return (0);
206 }
207 break;
208 default:
209 /* others not yet supported */
210 return (0);
211 }
212
213 if (hlen > m->m_pkthdr.len) {
214 m_freem(m);
215 return (EINVAL);
216 }
217 /* Unlike NetBSD, in FreeBSD m_adj() adjusts m->m_pkthdr.len as well */
218 m_adj(m, hlen);
219
220 if (GRE2IFP(sc)->if_bpf) {
|
211 u_int32_t af = AF_INET;
| |
212 bpf_mtap2(GRE2IFP(sc)->if_bpf, &af, sizeof(af), m);
213 }
214
215 m->m_pkthdr.rcvif = GRE2IFP(sc);
216
217 netisr_dispatch(isr, m);
218
219 return (1); /* packet is done, no further processing needed */
220}
221
222/*
223 * input routine for IPPRPOTO_MOBILE
224 * This is a little bit diffrent from the other modes, as the
225 * encapsulating header was not prepended, but instead inserted
226 * between IP header and payload
227 */
228
229void
230#if __STDC__
231gre_mobile_input(struct mbuf *m, ...)
232#else
233gre_mobile_input(m, va_alist)
234 struct mbuf *m;
235 va_dcl
236#endif
237{
238 struct ip *ip;
239 struct mobip_h *mip;
240 struct gre_softc *sc;
241 int hlen;
242 va_list ap;
243 int msiz;
244
245 va_start(ap, m);
246 hlen = va_arg(ap, int);
247 va_end(ap);
248
249 if ((sc = gre_lookup(m, IPPROTO_MOBILE)) == NULL) {
250 /* No matching tunnel or tunnel is down. */
251 m_freem(m);
252 return;
253 }
254
255 if (m->m_len < sizeof(*mip)) {
256 m = m_pullup(m, sizeof(*mip));
257 if (m == NULL)
258 return;
259 }
260 ip = mtod(m, struct ip *);
261 mip = mtod(m, struct mobip_h *);
262
263 GRE2IFP(sc)->if_ipackets++;
264 GRE2IFP(sc)->if_ibytes += m->m_pkthdr.len;
265
266 if (ntohs(mip->mh.proto) & MOB_H_SBIT) {
267 msiz = MOB_H_SIZ_L;
268 mip->mi.ip_src.s_addr = mip->mh.osrc;
269 } else
270 msiz = MOB_H_SIZ_S;
271
272 if (m->m_len < (ip->ip_hl << 2) + msiz) {
273 m = m_pullup(m, (ip->ip_hl << 2) + msiz);
274 if (m == NULL)
275 return;
276 ip = mtod(m, struct ip *);
277 mip = mtod(m, struct mobip_h *);
278 }
279
280 mip->mi.ip_dst.s_addr = mip->mh.odst;
281 mip->mi.ip_p = (ntohs(mip->mh.proto) >> 8);
282
283 if (gre_in_cksum((u_int16_t *)&mip->mh, msiz) != 0) {
284 m_freem(m);
285 return;
286 }
287
288 bcopy((caddr_t)(ip) + (ip->ip_hl << 2) + msiz, (caddr_t)(ip) +
289 (ip->ip_hl << 2), m->m_len - msiz - (ip->ip_hl << 2));
290 m->m_len -= msiz;
291 m->m_pkthdr.len -= msiz;
292
293 /*
294 * On FreeBSD, rip_input() supplies us with ip->ip_len
295 * already converted into host byteorder and also decreases
296 * it by the lengh of IP header, however, ip_input() expects
297 * that this field is in the original format (network byteorder
298 * and full size of IP packet), so that adjust accordingly.
299 */
300 ip->ip_len = htons(ip->ip_len + sizeof(struct ip) - msiz);
301
302 ip->ip_sum = 0;
303 ip->ip_sum = in_cksum(m, (ip->ip_hl << 2));
304
305 if (GRE2IFP(sc)->if_bpf) {
306 u_int32_t af = AF_INET;
307 bpf_mtap2(GRE2IFP(sc)->if_bpf, &af, sizeof(af), m);
308 }
309
310 m->m_pkthdr.rcvif = GRE2IFP(sc);
311
312 netisr_dispatch(NETISR_IP, m);
313}
314
315/*
316 * Find the gre interface associated with our src/dst/proto set.
317 *
318 * XXXRW: Need some sort of drain/refcount mechanism so that the softc
319 * reference remains valid after it's returned from gre_lookup(). Right
320 * now, I'm thinking it should be reference-counted with a gre_dropref()
321 * when the caller is done with the softc. This is complicated by how
322 * to handle destroying the gre softc; probably using a gre_drain() in
323 * in_gre.c during destroy.
324 */
325static struct gre_softc *
326gre_lookup(m, proto)
327 struct mbuf *m;
328 u_int8_t proto;
329{
330 struct ip *ip = mtod(m, struct ip *);
331 struct gre_softc *sc;
332
333 mtx_lock(&gre_mtx);
334 for (sc = LIST_FIRST(&gre_softc_list); sc != NULL;
335 sc = LIST_NEXT(sc, sc_list)) {
336 if ((sc->g_dst.s_addr == ip->ip_src.s_addr) &&
337 (sc->g_src.s_addr == ip->ip_dst.s_addr) &&
338 (sc->g_proto == proto) &&
339 ((GRE2IFP(sc)->if_flags & IFF_UP) != 0)) {
340 mtx_unlock(&gre_mtx);
341 return (sc);
342 }
343 }
344 mtx_unlock(&gre_mtx);
345
346 return (NULL);
347}
| 221 bpf_mtap2(GRE2IFP(sc)->if_bpf, &af, sizeof(af), m);
222 }
223
224 m->m_pkthdr.rcvif = GRE2IFP(sc);
225
226 netisr_dispatch(isr, m);
227
228 return (1); /* packet is done, no further processing needed */
229}
230
231/*
232 * input routine for IPPRPOTO_MOBILE
233 * This is a little bit diffrent from the other modes, as the
234 * encapsulating header was not prepended, but instead inserted
235 * between IP header and payload
236 */
237
238void
239#if __STDC__
240gre_mobile_input(struct mbuf *m, ...)
241#else
242gre_mobile_input(m, va_alist)
243 struct mbuf *m;
244 va_dcl
245#endif
246{
247 struct ip *ip;
248 struct mobip_h *mip;
249 struct gre_softc *sc;
250 int hlen;
251 va_list ap;
252 int msiz;
253
254 va_start(ap, m);
255 hlen = va_arg(ap, int);
256 va_end(ap);
257
258 if ((sc = gre_lookup(m, IPPROTO_MOBILE)) == NULL) {
259 /* No matching tunnel or tunnel is down. */
260 m_freem(m);
261 return;
262 }
263
264 if (m->m_len < sizeof(*mip)) {
265 m = m_pullup(m, sizeof(*mip));
266 if (m == NULL)
267 return;
268 }
269 ip = mtod(m, struct ip *);
270 mip = mtod(m, struct mobip_h *);
271
272 GRE2IFP(sc)->if_ipackets++;
273 GRE2IFP(sc)->if_ibytes += m->m_pkthdr.len;
274
275 if (ntohs(mip->mh.proto) & MOB_H_SBIT) {
276 msiz = MOB_H_SIZ_L;
277 mip->mi.ip_src.s_addr = mip->mh.osrc;
278 } else
279 msiz = MOB_H_SIZ_S;
280
281 if (m->m_len < (ip->ip_hl << 2) + msiz) {
282 m = m_pullup(m, (ip->ip_hl << 2) + msiz);
283 if (m == NULL)
284 return;
285 ip = mtod(m, struct ip *);
286 mip = mtod(m, struct mobip_h *);
287 }
288
289 mip->mi.ip_dst.s_addr = mip->mh.odst;
290 mip->mi.ip_p = (ntohs(mip->mh.proto) >> 8);
291
292 if (gre_in_cksum((u_int16_t *)&mip->mh, msiz) != 0) {
293 m_freem(m);
294 return;
295 }
296
297 bcopy((caddr_t)(ip) + (ip->ip_hl << 2) + msiz, (caddr_t)(ip) +
298 (ip->ip_hl << 2), m->m_len - msiz - (ip->ip_hl << 2));
299 m->m_len -= msiz;
300 m->m_pkthdr.len -= msiz;
301
302 /*
303 * On FreeBSD, rip_input() supplies us with ip->ip_len
304 * already converted into host byteorder and also decreases
305 * it by the lengh of IP header, however, ip_input() expects
306 * that this field is in the original format (network byteorder
307 * and full size of IP packet), so that adjust accordingly.
308 */
309 ip->ip_len = htons(ip->ip_len + sizeof(struct ip) - msiz);
310
311 ip->ip_sum = 0;
312 ip->ip_sum = in_cksum(m, (ip->ip_hl << 2));
313
314 if (GRE2IFP(sc)->if_bpf) {
315 u_int32_t af = AF_INET;
316 bpf_mtap2(GRE2IFP(sc)->if_bpf, &af, sizeof(af), m);
317 }
318
319 m->m_pkthdr.rcvif = GRE2IFP(sc);
320
321 netisr_dispatch(NETISR_IP, m);
322}
323
324/*
325 * Find the gre interface associated with our src/dst/proto set.
326 *
327 * XXXRW: Need some sort of drain/refcount mechanism so that the softc
328 * reference remains valid after it's returned from gre_lookup(). Right
329 * now, I'm thinking it should be reference-counted with a gre_dropref()
330 * when the caller is done with the softc. This is complicated by how
331 * to handle destroying the gre softc; probably using a gre_drain() in
332 * in_gre.c during destroy.
333 */
334static struct gre_softc *
335gre_lookup(m, proto)
336 struct mbuf *m;
337 u_int8_t proto;
338{
339 struct ip *ip = mtod(m, struct ip *);
340 struct gre_softc *sc;
341
342 mtx_lock(&gre_mtx);
343 for (sc = LIST_FIRST(&gre_softc_list); sc != NULL;
344 sc = LIST_NEXT(sc, sc_list)) {
345 if ((sc->g_dst.s_addr == ip->ip_src.s_addr) &&
346 (sc->g_src.s_addr == ip->ip_dst.s_addr) &&
347 (sc->g_proto == proto) &&
348 ((GRE2IFP(sc)->if_flags & IFF_UP) != 0)) {
349 mtx_unlock(&gre_mtx);
350 return (sc);
351 }
352 }
353 mtx_unlock(&gre_mtx);
354
355 return (NULL);
356}
|