1 /*-
2 * Copyright (c) 1984, 1985, 1986, 1987, 1993
3 * The Regents of the University of California.
4 * Copyright (c) 2004-2009 Robert N. M. Watson
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 4. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * Copyright (c) 1995, Mike Mitchell
32 * All rights reserved.
33 *
34 * Redistribution and use in source and binary forms, with or without
35 * modification, are permitted provided that the following conditions
36 * are met:
37 * 1. Redistributions of source code must retain the above copyright
38 * notice, this list of conditions and the following disclaimer.
39 * 2. Redistributions in binary form must reproduce the above copyright
40 * notice, this list of conditions and the following disclaimer in the
41 * documentation and/or other materials provided with the distribution.
42 * 3. All advertising materials mentioning features or use of this software
43 * must display the following acknowledgement:
44 * This product includes software developed by the University of
45 * California, Berkeley and its contributors.
46 * 4. Neither the name of the University nor the names of its contributors
47 * may be used to endorse or promote products derived from this software
48 * without specific prior written permission.
49 *
50 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60 * SUCH DAMAGE.
61 *
62 * @(#)ipx_input.c
63 */
64
65 #include <sys/cdefs.h>
66 __FBSDID("$FreeBSD$");
67
68 #include <sys/param.h>
69 #include <sys/systm.h>
70 #include <sys/mbuf.h>
71 #include <sys/protosw.h>
72 #include <sys/socket.h>
73 #include <sys/kernel.h>
74 #include <sys/random.h>
75 #include <sys/lock.h>
76 #include <sys/rwlock.h>
77 #include <sys/sysctl.h>
78
79 #include <net/if.h>
80 #include <net/route.h>
81 #include <net/netisr.h>
82
83 #include <netipx/ipx.h>
84 #include <netipx/spx.h>
85 #include <netipx/ipx_if.h>
86 #include <netipx/ipx_pcb.h>
87 #include <netipx/ipx_var.h>
88
89 int ipxcksum = 0;
90 SYSCTL_INT(_net_ipx_ipx, OID_AUTO, checksum, CTLFLAG_RW,
91 &ipxcksum, 0, "Compute ipx checksum");
92
93 static int ipxprintfs = 0; /* printing forwarding information */
94 SYSCTL_INT(_net_ipx_ipx, OID_AUTO, ipxprintfs, CTLFLAG_RW,
95 &ipxprintfs, 0, "Printing forwarding information");
96
97 static int ipxforwarding = 0;
98 SYSCTL_INT(_net_ipx_ipx, OID_AUTO, ipxforwarding, CTLFLAG_RW,
99 &ipxforwarding, 0, "Enable ipx forwarding");
100
101 static int ipxnetbios = 0;
102 SYSCTL_INT(_net_ipx, OID_AUTO, ipxnetbios, CTLFLAG_RW,
103 &ipxnetbios, 0, "Propagate netbios over ipx");
104
105 static int ipx_do_route(struct ipx_addr *src, struct route *ro);
106 static void ipx_undo_route(struct route *ro);
107 static void ipx_forward(struct mbuf *m);
108 static void ipxintr(struct mbuf *m);
109
110 const union ipx_net ipx_zeronet;
111
112 const union ipx_net ipx_broadnet = { .s_net[0] = 0xffff,
113 .s_net[1] = 0xffff };
114 const union ipx_host ipx_broadhost = { .s_host[0] = 0xffff,
115 .s_host[1] = 0xffff,
116 .s_host[2] = 0xffff };
117
118 struct ipxstat ipxstat;
119 struct sockaddr_ipx ipx_netmask, ipx_hostmask;
120
121 /*
122 * IPX protocol control block (pcb) lists.
123 */
124 struct mtx ipxpcb_list_mtx;
125 struct ipxpcbhead ipxpcb_list;
126 struct ipxpcbhead ipxrawpcb_list;
127
128 static struct netisr_handler ipx_nh = {
129 .nh_name = "ipx",
130 .nh_handler = ipxintr,
131 .nh_proto = NETISR_IPX,
132 .nh_policy = NETISR_POLICY_SOURCE,
133 };
134
135 long ipx_pexseq; /* Locked with ipxpcb_list_mtx. */
136
137 /*
138 * IPX initialization.
139 */
140
141 void
ipx_init(void)142 ipx_init(void)
143 {
144
145 read_random(&ipx_pexseq, sizeof ipx_pexseq);
146
147 LIST_INIT(&ipxpcb_list);
148 LIST_INIT(&ipxrawpcb_list);
149 TAILQ_INIT(&ipx_ifaddrhead);
150
151 IPX_LIST_LOCK_INIT();
152 IPX_IFADDR_LOCK_INIT();
153
154 ipx_netmask.sipx_len = 6;
155 ipx_netmask.sipx_addr.x_net = ipx_broadnet;
156
157 ipx_hostmask.sipx_len = 12;
158 ipx_hostmask.sipx_addr.x_net = ipx_broadnet;
159 ipx_hostmask.sipx_addr.x_host = ipx_broadhost;
160
161 netisr_register(&ipx_nh);
162 }
163
164 /*
165 * IPX input routine. Pass to next level.
166 */
167 static void
ipxintr(struct mbuf * m)168 ipxintr(struct mbuf *m)
169 {
170 struct ipx *ipx;
171 struct ipxpcb *ipxp;
172 struct ipx_ifaddr *ia;
173 int len;
174
175 /*
176 * If no IPX addresses have been set yet but the interfaces
177 * are receiving, can't do anything with incoming packets yet.
178 */
179 if (TAILQ_EMPTY(&ipx_ifaddrhead)) {
180 m_freem(m);
181 return;
182 }
183
184 ipxstat.ipxs_total++;
185
186 if ((m->m_flags & M_EXT || m->m_len < sizeof(struct ipx)) &&
187 (m = m_pullup(m, sizeof(struct ipx))) == NULL) {
188 ipxstat.ipxs_toosmall++;
189 return;
190 }
191
192 /*
193 * Give any raw listeners a crack at the packet
194 */
195 IPX_LIST_LOCK();
196 LIST_FOREACH(ipxp, &ipxrawpcb_list, ipxp_list) {
197 struct mbuf *m1 = m_copy(m, 0, (int)M_COPYALL);
198 if (m1 != NULL) {
199 IPX_LOCK(ipxp);
200 ipx_input(m1, ipxp);
201 IPX_UNLOCK(ipxp);
202 }
203 }
204 IPX_LIST_UNLOCK();
205
206 ipx = mtod(m, struct ipx *);
207 len = ntohs(ipx->ipx_len);
208 /*
209 * Check that the amount of data in the buffers
210 * is as at least much as the IPX header would have us expect.
211 * Trim mbufs if longer than we expect.
212 * Drop packet if shorter than we expect.
213 */
214 if (m->m_pkthdr.len < len) {
215 ipxstat.ipxs_tooshort++;
216 m_freem(m);
217 return;
218 }
219 if (m->m_pkthdr.len > len) {
220 if (m->m_len == m->m_pkthdr.len) {
221 m->m_len = len;
222 m->m_pkthdr.len = len;
223 } else
224 m_adj(m, len - m->m_pkthdr.len);
225 }
226 if (ipxcksum && ipx->ipx_sum != 0xffff) {
227 if (ipx->ipx_sum != ipx_cksum(m, len)) {
228 ipxstat.ipxs_badsum++;
229 m_freem(m);
230 return;
231 }
232 }
233
234 /*
235 * Propagated (Netbios) packets (type 20) has to be handled
236 * different. :-(
237 */
238 if (ipx->ipx_pt == IPXPROTO_NETBIOS) {
239 if (ipxnetbios) {
240 ipx_output_type20(m);
241 return;
242 } else {
243 m_freem(m);
244 return;
245 }
246 }
247
248 /*
249 * Is this a directed broadcast?
250 */
251 if (ipx_hosteqnh(ipx_broadhost,ipx->ipx_dna.x_host)) {
252 if ((!ipx_neteq(ipx->ipx_dna, ipx->ipx_sna)) &&
253 (!ipx_neteqnn(ipx->ipx_dna.x_net, ipx_broadnet)) &&
254 (!ipx_neteqnn(ipx->ipx_sna.x_net, ipx_zeronet)) &&
255 (!ipx_neteqnn(ipx->ipx_dna.x_net, ipx_zeronet)) ) {
256 /*
257 * If it is a broadcast to the net where it was
258 * received from, treat it as ours.
259 */
260 IPX_IFADDR_RLOCK();
261 TAILQ_FOREACH(ia, &ipx_ifaddrhead, ia_link) {
262 if ((ia->ia_ifa.ifa_ifp == m->m_pkthdr.rcvif)
263 && ipx_neteq(ia->ia_addr.sipx_addr,
264 ipx->ipx_dna)) {
265 IPX_IFADDR_RUNLOCK();
266 goto ours;
267 }
268 }
269 IPX_IFADDR_RUNLOCK();
270
271 /*
272 * Look to see if I need to eat this packet.
273 * Algorithm is to forward all young packets
274 * and prematurely age any packets which will
275 * by physically broadcasted.
276 * Any very old packets eaten without forwarding
277 * would die anyway.
278 *
279 * Suggestion of Bill Nesheim, Cornell U.
280 */
281 if (ipx->ipx_tc < IPX_MAXHOPS) {
282 ipx_forward(m);
283 return;
284 }
285 }
286 /*
287 * Is this our packet? If not, forward.
288 */
289 } else {
290 IPX_IFADDR_RLOCK();
291 TAILQ_FOREACH(ia, &ipx_ifaddrhead, ia_link) {
292 if (ipx_hosteq(ipx->ipx_dna, ia->ia_addr.sipx_addr) &&
293 (ipx_neteq(ipx->ipx_dna, ia->ia_addr.sipx_addr) ||
294 ipx_neteqnn(ipx->ipx_dna.x_net, ipx_zeronet)))
295 break;
296 }
297 IPX_IFADDR_RUNLOCK();
298 if (ia == NULL) {
299 ipx_forward(m);
300 return;
301 }
302 }
303 ours:
304 /*
305 * Locate pcb for datagram.
306 */
307 IPX_LIST_LOCK();
308 ipxp = ipx_pcblookup(&ipx->ipx_sna, ipx->ipx_dna.x_port, IPX_WILDCARD);
309 /*
310 * Switch out to protocol's input routine.
311 */
312 if (ipxp != NULL) {
313 ipxstat.ipxs_delivered++;
314 if ((ipxp->ipxp_flags & IPXP_ALL_PACKETS) == 0)
315 switch (ipx->ipx_pt) {
316 case IPXPROTO_SPX:
317 IPX_LOCK(ipxp);
318 /* Will release both locks. */
319 spx_input(m, ipxp);
320 return;
321 }
322 IPX_LOCK(ipxp);
323 ipx_input(m, ipxp);
324 IPX_UNLOCK(ipxp);
325 } else
326 m_freem(m);
327 IPX_LIST_UNLOCK();
328 }
329
330 void
ipx_ctlinput(cmd,arg_as_sa,dummy)331 ipx_ctlinput(cmd, arg_as_sa, dummy)
332 int cmd;
333 struct sockaddr *arg_as_sa; /* XXX should be swapped with dummy */
334 void *dummy;
335 {
336
337 /* Currently, nothing. */
338 }
339
340 /*
341 * Forward a packet. If some error occurs drop the packet. IPX don't
342 * have a way to return errors to the sender.
343 */
344
345 static struct route ipx_droute;
346 static struct route ipx_sroute;
347
348 static void
ipx_forward(struct mbuf * m)349 ipx_forward(struct mbuf *m)
350 {
351 struct ipx *ipx = mtod(m, struct ipx *);
352 int error;
353 int agedelta = 1;
354 int flags = IPX_FORWARDING;
355 int ok_there = 0;
356 int ok_back = 0;
357
358 if (ipxforwarding == 0) {
359 /* can't tell difference between net and host */
360 ipxstat.ipxs_cantforward++;
361 m_freem(m);
362 goto cleanup;
363 }
364 ipx->ipx_tc++;
365 if (ipx->ipx_tc > IPX_MAXHOPS) {
366 ipxstat.ipxs_cantforward++;
367 m_freem(m);
368 goto cleanup;
369 }
370
371 if ((ok_there = ipx_do_route(&ipx->ipx_dna,&ipx_droute)) == 0) {
372 ipxstat.ipxs_noroute++;
373 m_freem(m);
374 goto cleanup;
375 }
376 /*
377 * Here we think about forwarding broadcast packets,
378 * so we try to insure that it doesn't go back out
379 * on the interface it came in on. Also, if we
380 * are going to physically broadcast this, let us
381 * age the packet so we can eat it safely the second time around.
382 */
383 if (ipx->ipx_dna.x_host.c_host[0] & 0x1) {
384 struct ipx_ifaddr *ia;
385 struct ifnet *ifp;
386
387 IPX_IFADDR_RLOCK();
388 ia = ipx_iaonnetof(&ipx->ipx_dna);
389 if (ia != NULL) {
390 /* I'm gonna hafta eat this packet */
391 agedelta += IPX_MAXHOPS - ipx->ipx_tc;
392 ipx->ipx_tc = IPX_MAXHOPS;
393 }
394 IPX_IFADDR_RUNLOCK();
395 if ((ok_back = ipx_do_route(&ipx->ipx_sna,&ipx_sroute)) == 0) {
396 /* error = ENETUNREACH; He'll never get it! */
397 ipxstat.ipxs_noroute++;
398 m_freem(m);
399 goto cleanup;
400 }
401 if (ipx_droute.ro_rt &&
402 (ifp = ipx_droute.ro_rt->rt_ifp) &&
403 ipx_sroute.ro_rt &&
404 (ifp != ipx_sroute.ro_rt->rt_ifp)) {
405 flags |= IPX_ALLOWBROADCAST;
406 } else {
407 ipxstat.ipxs_noroute++;
408 m_freem(m);
409 goto cleanup;
410 }
411 }
412 /*
413 * We don't need to recompute checksum because ipx_tc field
414 * is ignored by checksum calculation routine, however
415 * it may be desirable to reset checksum if ipxcksum == 0
416 */
417 #if 0
418 if (!ipxcksum)
419 ipx->ipx_sum = 0xffff;
420 #endif
421
422 error = ipx_outputfl(m, &ipx_droute, flags);
423 if (error == 0) {
424 ipxstat.ipxs_forward++;
425
426 if (ipxprintfs) {
427 printf("forward: ");
428 ipx_printhost(&ipx->ipx_sna);
429 printf(" to ");
430 ipx_printhost(&ipx->ipx_dna);
431 printf(" hops %d\n", ipx->ipx_tc);
432 }
433 }
434 cleanup:
435 if (ok_there)
436 ipx_undo_route(&ipx_droute);
437 if (ok_back)
438 ipx_undo_route(&ipx_sroute);
439 }
440
441 static int
ipx_do_route(struct ipx_addr * src,struct route * ro)442 ipx_do_route(struct ipx_addr *src, struct route *ro)
443 {
444 struct sockaddr_ipx *dst;
445
446 bzero((caddr_t)ro, sizeof(*ro));
447 dst = (struct sockaddr_ipx *)&ro->ro_dst;
448
449 dst->sipx_len = sizeof(*dst);
450 dst->sipx_family = AF_IPX;
451 dst->sipx_addr = *src;
452 dst->sipx_addr.x_port = 0;
453 rtalloc_ign(ro, 0);
454 if (ro->ro_rt == NULL || ro->ro_rt->rt_ifp == NULL) {
455 return (0);
456 }
457 counter_u64_add(ro->ro_rt->rt_pksent, 1);
458 return (1);
459 }
460
461 static void
ipx_undo_route(struct route * ro)462 ipx_undo_route(struct route *ro)
463 {
464
465 if (ro->ro_rt != NULL) {
466 RTFREE(ro->ro_rt);
467 }
468 }
469