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Linux 5.7.7
[linux/fpc-iii.git] / net / appletalk / ddp.c
blobb41375d4d295d0299d67701d5a4502fd57acb1ad
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * DDP: An implementation of the AppleTalk DDP protocol for
4 * Ethernet 'ELAP'.
5 *
6 * Alan Cox <alan@lxorguk.ukuu.org.uk>
7 *
8 * With more than a little assistance from
9 *
10 * Wesley Craig <netatalk@umich.edu>
11 *
12 * Fixes:
13 * Neil Horman : Added missing device ioctls
14 * Michael Callahan : Made routing work
15 * Wesley Craig : Fix probing to listen to a
16 * passed node id.
17 * Alan Cox : Added send/recvmsg support
18 * Alan Cox : Moved at. to protinfo in
19 * socket.
20 * Alan Cox : Added firewall hooks.
21 * Alan Cox : Supports new ARPHRD_LOOPBACK
22 * Christer Weinigel : Routing and /proc fixes.
23 * Bradford Johnson : LocalTalk.
24 * Tom Dyas : Module support.
25 * Alan Cox : Hooks for PPP (based on the
26 * LocalTalk hook).
27 * Alan Cox : Posix bits
28 * Alan Cox/Mike Freeman : Possible fix to NBP problems
29 * Bradford Johnson : IP-over-DDP (experimental)
30 * Jay Schulist : Moved IP-over-DDP to its own
31 * driver file. (ipddp.c & ipddp.h)
32 * Jay Schulist : Made work as module with
33 * AppleTalk drivers, cleaned it.
34 * Rob Newberry : Added proxy AARP and AARP
35 * procfs, moved probing to AARP
36 * module.
37 * Adrian Sun/
38 * Michael Zuelsdorff : fix for net.0 packets. don't
39 * allow illegal ether/tokentalk
40 * port assignment. we lose a
41 * valid localtalk port as a
42 * result.
43 * Arnaldo C. de Melo : Cleanup, in preparation for
44 * shared skb support 8)
45 * Arnaldo C. de Melo : Move proc stuff to atalk_proc.c,
46 * use seq_file
47 */
48
49 #include <linux/capability.h>
50 #include <linux/module.h>
51 #include <linux/if_arp.h>
52 #include <linux/termios.h> /* For TIOCOUTQ/INQ */
53 #include <linux/compat.h>
54 #include <linux/slab.h>
55 #include <net/datalink.h>
56 #include <net/psnap.h>
57 #include <net/sock.h>
58 #include <net/tcp_states.h>
59 #include <net/route.h>
60 #include <linux/atalk.h>
61 #include <linux/highmem.h>
62
63 struct datalink_proto *ddp_dl, *aarp_dl;
64 static const struct proto_ops atalk_dgram_ops;
65
66 /**************************************************************************\
67 * *
68 * Handlers for the socket list. *
69 * *
70 \**************************************************************************/
71
72 HLIST_HEAD(atalk_sockets);
73 DEFINE_RWLOCK(atalk_sockets_lock);
74
75 static inline void __atalk_insert_socket(struct sock *sk)
76 {
77 sk_add_node(sk, &atalk_sockets);
78 }
79
80 static inline void atalk_remove_socket(struct sock *sk)
81 {
82 write_lock_bh(&atalk_sockets_lock);
83 sk_del_node_init(sk);
84 write_unlock_bh(&atalk_sockets_lock);
85 }
86
87 static struct sock *atalk_search_socket(struct sockaddr_at *to,
88 struct atalk_iface *atif)
89 {
90 struct sock *s;
91
92 read_lock_bh(&atalk_sockets_lock);
93 sk_for_each(s, &atalk_sockets) {
94 struct atalk_sock *at = at_sk(s);
95
96 if (to->sat_port != at->src_port)
97 continue;
98
99 if (to->sat_addr.s_net == ATADDR_ANYNET &&
100 to->sat_addr.s_node == ATADDR_BCAST)
101 goto found;
102
103 if (to->sat_addr.s_net == at->src_net &&
104 (to->sat_addr.s_node == at->src_node ||
105 to->sat_addr.s_node == ATADDR_BCAST ||
106 to->sat_addr.s_node == ATADDR_ANYNODE))
107 goto found;
108
109 /* XXXX.0 -- we got a request for this router. make sure
110 * that the node is appropriately set. */
111 if (to->sat_addr.s_node == ATADDR_ANYNODE &&
112 to->sat_addr.s_net != ATADDR_ANYNET &&
113 atif->address.s_node == at->src_node) {
114 to->sat_addr.s_node = atif->address.s_node;
115 goto found;
116 }
117 }
118 s = NULL;
119 found:
120 read_unlock_bh(&atalk_sockets_lock);
121 return s;
122 }
123
124 /**
125 * atalk_find_or_insert_socket - Try to find a socket matching ADDR
126 * @sk: socket to insert in the list if it is not there already
127 * @sat: address to search for
128 *
129 * Try to find a socket matching ADDR in the socket list, if found then return
130 * it. If not, insert SK into the socket list.
131 *
132 * This entire operation must execute atomically.
133 */
134 static struct sock *atalk_find_or_insert_socket(struct sock *sk,
135 struct sockaddr_at *sat)
136 {
137 struct sock *s;
138 struct atalk_sock *at;
139
140 write_lock_bh(&atalk_sockets_lock);
141 sk_for_each(s, &atalk_sockets) {
142 at = at_sk(s);
143
144 if (at->src_net == sat->sat_addr.s_net &&
145 at->src_node == sat->sat_addr.s_node &&
146 at->src_port == sat->sat_port)
147 goto found;
148 }
149 s = NULL;
150 __atalk_insert_socket(sk); /* Wheee, it's free, assign and insert. */
151 found:
152 write_unlock_bh(&atalk_sockets_lock);
153 return s;
154 }
155
156 static void atalk_destroy_timer(struct timer_list *t)
157 {
158 struct sock *sk = from_timer(sk, t, sk_timer);
159
160 if (sk_has_allocations(sk)) {
161 sk->sk_timer.expires = jiffies + SOCK_DESTROY_TIME;
162 add_timer(&sk->sk_timer);
163 } else
164 sock_put(sk);
165 }
166
167 static inline void atalk_destroy_socket(struct sock *sk)
168 {
169 atalk_remove_socket(sk);
170 skb_queue_purge(&sk->sk_receive_queue);
171
172 if (sk_has_allocations(sk)) {
173 timer_setup(&sk->sk_timer, atalk_destroy_timer, 0);
174 sk->sk_timer.expires = jiffies + SOCK_DESTROY_TIME;
175 add_timer(&sk->sk_timer);
176 } else
177 sock_put(sk);
178 }
179
180 /**************************************************************************\
181 * *
182 * Routing tables for the AppleTalk socket layer. *
183 * *
184 \**************************************************************************/
185
186 /* Anti-deadlock ordering is atalk_routes_lock --> iface_lock -DaveM */
187 struct atalk_route *atalk_routes;
188 DEFINE_RWLOCK(atalk_routes_lock);
189
190 struct atalk_iface *atalk_interfaces;
191 DEFINE_RWLOCK(atalk_interfaces_lock);
192
193 /* For probing devices or in a routerless network */
194 struct atalk_route atrtr_default;
195
196 /* AppleTalk interface control */
197 /*
198 * Drop a device. Doesn't drop any of its routes - that is the caller's
199 * problem. Called when we down the interface or delete the address.
200 */
201 static void atif_drop_device(struct net_device *dev)
202 {
203 struct atalk_iface **iface = &atalk_interfaces;
204 struct atalk_iface *tmp;
205
206 write_lock_bh(&atalk_interfaces_lock);
207 while ((tmp = *iface) != NULL) {
208 if (tmp->dev == dev) {
209 *iface = tmp->next;
210 dev_put(dev);
211 kfree(tmp);
212 dev->atalk_ptr = NULL;
213 } else
214 iface = &tmp->next;
215 }
216 write_unlock_bh(&atalk_interfaces_lock);
217 }
218
219 static struct atalk_iface *atif_add_device(struct net_device *dev,
220 struct atalk_addr *sa)
221 {
222 struct atalk_iface *iface = kzalloc(sizeof(*iface), GFP_KERNEL);
223
224 if (!iface)
225 goto out;
226
227 dev_hold(dev);
228 iface->dev = dev;
229 dev->atalk_ptr = iface;
230 iface->address = *sa;
231 iface->status = 0;
232
233 write_lock_bh(&atalk_interfaces_lock);
234 iface->next = atalk_interfaces;
235 atalk_interfaces = iface;
236 write_unlock_bh(&atalk_interfaces_lock);
237 out:
238 return iface;
239 }
240
241 /* Perform phase 2 AARP probing on our tentative address */
242 static int atif_probe_device(struct atalk_iface *atif)
243 {
244 int netrange = ntohs(atif->nets.nr_lastnet) -
245 ntohs(atif->nets.nr_firstnet) + 1;
246 int probe_net = ntohs(atif->address.s_net);
247 int probe_node = atif->address.s_node;
248 int netct, nodect;
249
250 /* Offset the network we start probing with */
251 if (probe_net == ATADDR_ANYNET) {
252 probe_net = ntohs(atif->nets.nr_firstnet);
253 if (netrange)
254 probe_net += jiffies % netrange;
255 }
256 if (probe_node == ATADDR_ANYNODE)
257 probe_node = jiffies & 0xFF;
258
259 /* Scan the networks */
260 atif->status |= ATIF_PROBE;
261 for (netct = 0; netct <= netrange; netct++) {
262 /* Sweep the available nodes from a given start */
263 atif->address.s_net = htons(probe_net);
264 for (nodect = 0; nodect < 256; nodect++) {
265 atif->address.s_node = (nodect + probe_node) & 0xFF;
266 if (atif->address.s_node > 0 &&
267 atif->address.s_node < 254) {
268 /* Probe a proposed address */
269 aarp_probe_network(atif);
270
271 if (!(atif->status & ATIF_PROBE_FAIL)) {
272 atif->status &= ~ATIF_PROBE;
273 return 0;
274 }
275 }
276 atif->status &= ~ATIF_PROBE_FAIL;
277 }
278 probe_net++;
279 if (probe_net > ntohs(atif->nets.nr_lastnet))
280 probe_net = ntohs(atif->nets.nr_firstnet);
281 }
282 atif->status &= ~ATIF_PROBE;
283
284 return -EADDRINUSE; /* Network is full... */
285 }
286
287
288 /* Perform AARP probing for a proxy address */
289 static int atif_proxy_probe_device(struct atalk_iface *atif,
290 struct atalk_addr *proxy_addr)
291 {
292 int netrange = ntohs(atif->nets.nr_lastnet) -
293 ntohs(atif->nets.nr_firstnet) + 1;
294 /* we probe the interface's network */
295 int probe_net = ntohs(atif->address.s_net);
296 int probe_node = ATADDR_ANYNODE; /* we'll take anything */
297 int netct, nodect;
298
299 /* Offset the network we start probing with */
300 if (probe_net == ATADDR_ANYNET) {
301 probe_net = ntohs(atif->nets.nr_firstnet);
302 if (netrange)
303 probe_net += jiffies % netrange;
304 }
305
306 if (probe_node == ATADDR_ANYNODE)
307 probe_node = jiffies & 0xFF;
308
309 /* Scan the networks */
310 for (netct = 0; netct <= netrange; netct++) {
311 /* Sweep the available nodes from a given start */
312 proxy_addr->s_net = htons(probe_net);
313 for (nodect = 0; nodect < 256; nodect++) {
314 proxy_addr->s_node = (nodect + probe_node) & 0xFF;
315 if (proxy_addr->s_node > 0 &&
316 proxy_addr->s_node < 254) {
317 /* Tell AARP to probe a proposed address */
318 int ret = aarp_proxy_probe_network(atif,
319 proxy_addr);
320
321 if (ret != -EADDRINUSE)
322 return ret;
323 }
324 }
325 probe_net++;
326 if (probe_net > ntohs(atif->nets.nr_lastnet))
327 probe_net = ntohs(atif->nets.nr_firstnet);
328 }
329
330 return -EADDRINUSE; /* Network is full... */
331 }
332
333
334 struct atalk_addr *atalk_find_dev_addr(struct net_device *dev)
335 {
336 struct atalk_iface *iface = dev->atalk_ptr;
337 return iface ? &iface->address : NULL;
338 }
339
340 static struct atalk_addr *atalk_find_primary(void)
341 {
342 struct atalk_iface *fiface = NULL;
343 struct atalk_addr *retval;
344 struct atalk_iface *iface;
345
346 /*
347 * Return a point-to-point interface only if
348 * there is no non-ptp interface available.
349 */
350 read_lock_bh(&atalk_interfaces_lock);
351 for (iface = atalk_interfaces; iface; iface = iface->next) {
352 if (!fiface && !(iface->dev->flags & IFF_LOOPBACK))
353 fiface = iface;
354 if (!(iface->dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT))) {
355 retval = &iface->address;
356 goto out;
357 }
358 }
359
360 if (fiface)
361 retval = &fiface->address;
362 else if (atalk_interfaces)
363 retval = &atalk_interfaces->address;
364 else
365 retval = NULL;
366 out:
367 read_unlock_bh(&atalk_interfaces_lock);
368 return retval;
369 }
370
371 /*
372 * Find a match for 'any network' - ie any of our interfaces with that
373 * node number will do just nicely.
374 */
375 static struct atalk_iface *atalk_find_anynet(int node, struct net_device *dev)
376 {
377 struct atalk_iface *iface = dev->atalk_ptr;
378
379 if (!iface || iface->status & ATIF_PROBE)
380 goto out_err;
381
382 if (node != ATADDR_BCAST &&
383 iface->address.s_node != node &&
384 node != ATADDR_ANYNODE)
385 goto out_err;
386 out:
387 return iface;
388 out_err:
389 iface = NULL;
390 goto out;
391 }
392
393 /* Find a match for a specific network:node pair */
394 static struct atalk_iface *atalk_find_interface(__be16 net, int node)
395 {
396 struct atalk_iface *iface;
397
398 read_lock_bh(&atalk_interfaces_lock);
399 for (iface = atalk_interfaces; iface; iface = iface->next) {
400 if ((node == ATADDR_BCAST ||
401 node == ATADDR_ANYNODE ||
402 iface->address.s_node == node) &&
403 iface->address.s_net == net &&
404 !(iface->status & ATIF_PROBE))
405 break;
406
407 /* XXXX.0 -- net.0 returns the iface associated with net */
408 if (node == ATADDR_ANYNODE && net != ATADDR_ANYNET &&
409 ntohs(iface->nets.nr_firstnet) <= ntohs(net) &&
410 ntohs(net) <= ntohs(iface->nets.nr_lastnet))
411 break;
412 }
413 read_unlock_bh(&atalk_interfaces_lock);
414 return iface;
415 }
416
417
418 /*
419 * Find a route for an AppleTalk packet. This ought to get cached in
420 * the socket (later on...). We know about host routes and the fact
421 * that a route must be direct to broadcast.
422 */
423 static struct atalk_route *atrtr_find(struct atalk_addr *target)
424 {
425 /*
426 * we must search through all routes unless we find a
427 * host route, because some host routes might overlap
428 * network routes
429 */
430 struct atalk_route *net_route = NULL;
431 struct atalk_route *r;
432
433 read_lock_bh(&atalk_routes_lock);
434 for (r = atalk_routes; r; r = r->next) {
435 if (!(r->flags & RTF_UP))
436 continue;
437
438 if (r->target.s_net == target->s_net) {
439 if (r->flags & RTF_HOST) {
440 /*
441 * if this host route is for the target,
442 * the we're done
443 */
444 if (r->target.s_node == target->s_node)
445 goto out;
446 } else
447 /*
448 * this route will work if there isn't a
449 * direct host route, so cache it
450 */
451 net_route = r;
452 }
453 }
454
455 /*
456 * if we found a network route but not a direct host
457 * route, then return it
458 */
459 if (net_route)
460 r = net_route;
461 else if (atrtr_default.dev)
462 r = &atrtr_default;
463 else /* No route can be found */
464 r = NULL;
465 out:
466 read_unlock_bh(&atalk_routes_lock);
467 return r;
468 }
469
470
471 /*
472 * Given an AppleTalk network, find the device to use. This can be
473 * a simple lookup.
474 */
475 struct net_device *atrtr_get_dev(struct atalk_addr *sa)
476 {
477 struct atalk_route *atr = atrtr_find(sa);
478 return atr ? atr->dev : NULL;
479 }
480
481 /* Set up a default router */
482 static void atrtr_set_default(struct net_device *dev)
483 {
484 atrtr_default.dev = dev;
485 atrtr_default.flags = RTF_UP;
486 atrtr_default.gateway.s_net = htons(0);
487 atrtr_default.gateway.s_node = 0;
488 }
489
490 /*
491 * Add a router. Basically make sure it looks valid and stuff the
492 * entry in the list. While it uses netranges we always set them to one
493 * entry to work like netatalk.
494 */
495 static int atrtr_create(struct rtentry *r, struct net_device *devhint)
496 {
497 struct sockaddr_at *ta = (struct sockaddr_at *)&r->rt_dst;
498 struct sockaddr_at *ga = (struct sockaddr_at *)&r->rt_gateway;
499 struct atalk_route *rt;
500 struct atalk_iface *iface, *riface;
501 int retval = -EINVAL;
502
503 /*
504 * Fixme: Raise/Lower a routing change semaphore for these
505 * operations.
506 */
507
508 /* Validate the request */
509 if (ta->sat_family != AF_APPLETALK ||
510 (!devhint && ga->sat_family != AF_APPLETALK))
511 goto out;
512
513 /* Now walk the routing table and make our decisions */
514 write_lock_bh(&atalk_routes_lock);
515 for (rt = atalk_routes; rt; rt = rt->next) {
516 if (r->rt_flags != rt->flags)
517 continue;
518
519 if (ta->sat_addr.s_net == rt->target.s_net) {
520 if (!(rt->flags & RTF_HOST))
521 break;
522 if (ta->sat_addr.s_node == rt->target.s_node)
523 break;
524 }
525 }
526
527 if (!devhint) {
528 riface = NULL;
529
530 read_lock_bh(&atalk_interfaces_lock);
531 for (iface = atalk_interfaces; iface; iface = iface->next) {
532 if (!riface &&
533 ntohs(ga->sat_addr.s_net) >=
534 ntohs(iface->nets.nr_firstnet) &&
535 ntohs(ga->sat_addr.s_net) <=
536 ntohs(iface->nets.nr_lastnet))
537 riface = iface;
538
539 if (ga->sat_addr.s_net == iface->address.s_net &&
540 ga->sat_addr.s_node == iface->address.s_node)
541 riface = iface;
542 }
543 read_unlock_bh(&atalk_interfaces_lock);
544
545 retval = -ENETUNREACH;
546 if (!riface)
547 goto out_unlock;
548
549 devhint = riface->dev;
550 }
551
552 if (!rt) {
553 rt = kzalloc(sizeof(*rt), GFP_ATOMIC);
554
555 retval = -ENOBUFS;
556 if (!rt)
557 goto out_unlock;
558
559 rt->next = atalk_routes;
560 atalk_routes = rt;
561 }
562
563 /* Fill in the routing entry */
564 rt->target = ta->sat_addr;
565 dev_hold(devhint);
566 rt->dev = devhint;
567 rt->flags = r->rt_flags;
568 rt->gateway = ga->sat_addr;
569
570 retval = 0;
571 out_unlock:
572 write_unlock_bh(&atalk_routes_lock);
573 out:
574 return retval;
575 }
576
577 /* Delete a route. Find it and discard it */
578 static int atrtr_delete(struct atalk_addr *addr)
579 {
580 struct atalk_route **r = &atalk_routes;
581 int retval = 0;
582 struct atalk_route *tmp;
583
584 write_lock_bh(&atalk_routes_lock);
585 while ((tmp = *r) != NULL) {
586 if (tmp->target.s_net == addr->s_net &&
587 (!(tmp->flags&RTF_GATEWAY) ||
588 tmp->target.s_node == addr->s_node)) {
589 *r = tmp->next;
590 dev_put(tmp->dev);
591 kfree(tmp);
592 goto out;
593 }
594 r = &tmp->next;
595 }
596 retval = -ENOENT;
597 out:
598 write_unlock_bh(&atalk_routes_lock);
599 return retval;
600 }
601
602 /*
603 * Called when a device is downed. Just throw away any routes
604 * via it.
605 */
606 static void atrtr_device_down(struct net_device *dev)
607 {
608 struct atalk_route **r = &atalk_routes;
609 struct atalk_route *tmp;
610
611 write_lock_bh(&atalk_routes_lock);
612 while ((tmp = *r) != NULL) {
613 if (tmp->dev == dev) {
614 *r = tmp->next;
615 dev_put(dev);
616 kfree(tmp);
617 } else
618 r = &tmp->next;
619 }
620 write_unlock_bh(&atalk_routes_lock);
621
622 if (atrtr_default.dev == dev)
623 atrtr_set_default(NULL);
624 }
625
626 /* Actually down the interface */
627 static inline void atalk_dev_down(struct net_device *dev)
628 {
629 atrtr_device_down(dev); /* Remove all routes for the device */
630 aarp_device_down(dev); /* Remove AARP entries for the device */
631 atif_drop_device(dev); /* Remove the device */
632 }
633
634 /*
635 * A device event has occurred. Watch for devices going down and
636 * delete our use of them (iface and route).
637 */
638 static int ddp_device_event(struct notifier_block *this, unsigned long event,
639 void *ptr)
640 {
641 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
642
643 if (!net_eq(dev_net(dev), &init_net))
644 return NOTIFY_DONE;
645
646 if (event == NETDEV_DOWN)
647 /* Discard any use of this */
648 atalk_dev_down(dev);
649
650 return NOTIFY_DONE;
651 }
652
653 /* ioctl calls. Shouldn't even need touching */
654 /* Device configuration ioctl calls */
655 static int atif_ioctl(int cmd, void __user *arg)
656 {
657 static char aarp_mcast[6] = { 0x09, 0x00, 0x00, 0xFF, 0xFF, 0xFF };
658 struct ifreq atreq;
659 struct atalk_netrange *nr;
660 struct sockaddr_at *sa;
661 struct net_device *dev;
662 struct atalk_iface *atif;
663 int ct;
664 int limit;
665 struct rtentry rtdef;
666 int add_route;
667
668 if (copy_from_user(&atreq, arg, sizeof(atreq)))
669 return -EFAULT;
670
671 dev = __dev_get_by_name(&init_net, atreq.ifr_name);
672 if (!dev)
673 return -ENODEV;
674
675 sa = (struct sockaddr_at *)&atreq.ifr_addr;
676 atif = atalk_find_dev(dev);
677
678 switch (cmd) {
679 case SIOCSIFADDR:
680 if (!capable(CAP_NET_ADMIN))
681 return -EPERM;
682 if (sa->sat_family != AF_APPLETALK)
683 return -EINVAL;
684 if (dev->type != ARPHRD_ETHER &&
685 dev->type != ARPHRD_LOOPBACK &&
686 dev->type != ARPHRD_LOCALTLK &&
687 dev->type != ARPHRD_PPP)
688 return -EPROTONOSUPPORT;
689
690 nr = (struct atalk_netrange *)&sa->sat_zero[0];
691 add_route = 1;
692
693 /*
694 * if this is a point-to-point iface, and we already
695 * have an iface for this AppleTalk address, then we
696 * should not add a route
697 */
698 if ((dev->flags & IFF_POINTOPOINT) &&
699 atalk_find_interface(sa->sat_addr.s_net,
700 sa->sat_addr.s_node)) {
701 printk(KERN_DEBUG "AppleTalk: point-to-point "
702 "interface added with "
703 "existing address\n");
704 add_route = 0;
705 }
706
707 /*
708 * Phase 1 is fine on LocalTalk but we don't do
709 * EtherTalk phase 1. Anyone wanting to add it go ahead.
710 */
711 if (dev->type == ARPHRD_ETHER && nr->nr_phase != 2)
712 return -EPROTONOSUPPORT;
713 if (sa->sat_addr.s_node == ATADDR_BCAST ||
714 sa->sat_addr.s_node == 254)
715 return -EINVAL;
716 if (atif) {
717 /* Already setting address */
718 if (atif->status & ATIF_PROBE)
719 return -EBUSY;
720
721 atif->address.s_net = sa->sat_addr.s_net;
722 atif->address.s_node = sa->sat_addr.s_node;
723 atrtr_device_down(dev); /* Flush old routes */
724 } else {
725 atif = atif_add_device(dev, &sa->sat_addr);
726 if (!atif)
727 return -ENOMEM;
728 }
729 atif->nets = *nr;
730
731 /*
732 * Check if the chosen address is used. If so we
733 * error and atalkd will try another.
734 */
735
736 if (!(dev->flags & IFF_LOOPBACK) &&
737 !(dev->flags & IFF_POINTOPOINT) &&
738 atif_probe_device(atif) < 0) {
739 atif_drop_device(dev);
740 return -EADDRINUSE;
741 }
742
743 /* Hey it worked - add the direct routes */
744 sa = (struct sockaddr_at *)&rtdef.rt_gateway;
745 sa->sat_family = AF_APPLETALK;
746 sa->sat_addr.s_net = atif->address.s_net;
747 sa->sat_addr.s_node = atif->address.s_node;
748 sa = (struct sockaddr_at *)&rtdef.rt_dst;
749 rtdef.rt_flags = RTF_UP;
750 sa->sat_family = AF_APPLETALK;
751 sa->sat_addr.s_node = ATADDR_ANYNODE;
752 if (dev->flags & IFF_LOOPBACK ||
753 dev->flags & IFF_POINTOPOINT)
754 rtdef.rt_flags |= RTF_HOST;
755
756 /* Routerless initial state */
757 if (nr->nr_firstnet == htons(0) &&
758 nr->nr_lastnet == htons(0xFFFE)) {
759 sa->sat_addr.s_net = atif->address.s_net;
760 atrtr_create(&rtdef, dev);
761 atrtr_set_default(dev);
762 } else {
763 limit = ntohs(nr->nr_lastnet);
764 if (limit - ntohs(nr->nr_firstnet) > 4096) {
765 printk(KERN_WARNING "Too many routes/"
766 "iface.\n");
767 return -EINVAL;
768 }
769 if (add_route)
770 for (ct = ntohs(nr->nr_firstnet);
771 ct <= limit; ct++) {
772 sa->sat_addr.s_net = htons(ct);
773 atrtr_create(&rtdef, dev);
774 }
775 }
776 dev_mc_add_global(dev, aarp_mcast);
777 return 0;
778
779 case SIOCGIFADDR:
780 if (!atif)
781 return -EADDRNOTAVAIL;
782
783 sa->sat_family = AF_APPLETALK;
784 sa->sat_addr = atif->address;
785 break;
786
787 case SIOCGIFBRDADDR:
788 if (!atif)
789 return -EADDRNOTAVAIL;
790
791 sa->sat_family = AF_APPLETALK;
792 sa->sat_addr.s_net = atif->address.s_net;
793 sa->sat_addr.s_node = ATADDR_BCAST;
794 break;
795
796 case SIOCATALKDIFADDR:
797 case SIOCDIFADDR:
798 if (!capable(CAP_NET_ADMIN))
799 return -EPERM;
800 if (sa->sat_family != AF_APPLETALK)
801 return -EINVAL;
802 atalk_dev_down(dev);
803 break;
804
805 case SIOCSARP:
806 if (!capable(CAP_NET_ADMIN))
807 return -EPERM;
808 if (sa->sat_family != AF_APPLETALK)
809 return -EINVAL;
810 /*
811 * for now, we only support proxy AARP on ELAP;
812 * we should be able to do it for LocalTalk, too.
813 */
814 if (dev->type != ARPHRD_ETHER)
815 return -EPROTONOSUPPORT;
816
817 /*
818 * atif points to the current interface on this network;
819 * we aren't concerned about its current status (at
820 * least for now), but it has all the settings about
821 * the network we're going to probe. Consequently, it
822 * must exist.
823 */
824 if (!atif)
825 return -EADDRNOTAVAIL;
826
827 nr = (struct atalk_netrange *)&(atif->nets);
828 /*
829 * Phase 1 is fine on Localtalk but we don't do
830 * Ethertalk phase 1. Anyone wanting to add it go ahead.
831 */
832 if (dev->type == ARPHRD_ETHER && nr->nr_phase != 2)
833 return -EPROTONOSUPPORT;
834
835 if (sa->sat_addr.s_node == ATADDR_BCAST ||
836 sa->sat_addr.s_node == 254)
837 return -EINVAL;
838
839 /*
840 * Check if the chosen address is used. If so we
841 * error and ATCP will try another.
842 */
843 if (atif_proxy_probe_device(atif, &(sa->sat_addr)) < 0)
844 return -EADDRINUSE;
845
846 /*
847 * We now have an address on the local network, and
848 * the AARP code will defend it for us until we take it
849 * down. We don't set up any routes right now, because
850 * ATCP will install them manually via SIOCADDRT.
851 */
852 break;
853
854 case SIOCDARP:
855 if (!capable(CAP_NET_ADMIN))
856 return -EPERM;
857 if (sa->sat_family != AF_APPLETALK)
858 return -EINVAL;
859 if (!atif)
860 return -EADDRNOTAVAIL;
861
862 /* give to aarp module to remove proxy entry */
863 aarp_proxy_remove(atif->dev, &(sa->sat_addr));
864 return 0;
865 }
866
867 return copy_to_user(arg, &atreq, sizeof(atreq)) ? -EFAULT : 0;
868 }
869
870 /* Routing ioctl() calls */
871 static int atrtr_ioctl(unsigned int cmd, void __user *arg)
872 {
873 struct rtentry rt;
874
875 if (copy_from_user(&rt, arg, sizeof(rt)))
876 return -EFAULT;
877
878 switch (cmd) {
879 case SIOCDELRT:
880 if (rt.rt_dst.sa_family != AF_APPLETALK)
881 return -EINVAL;
882 return atrtr_delete(&((struct sockaddr_at *)
883 &rt.rt_dst)->sat_addr);
884
885 case SIOCADDRT: {
886 struct net_device *dev = NULL;
887 if (rt.rt_dev) {
888 char name[IFNAMSIZ];
889 if (copy_from_user(name, rt.rt_dev, IFNAMSIZ-1))
890 return -EFAULT;
891 name[IFNAMSIZ-1] = '\0';
892 dev = __dev_get_by_name(&init_net, name);
893 if (!dev)
894 return -ENODEV;
895 }
896 return atrtr_create(&rt, dev);
897 }
898 }
899 return -EINVAL;
900 }
901
902 /**************************************************************************\
903 * *
904 * Handling for system calls applied via the various interfaces to an *
905 * AppleTalk socket object. *
906 * *
907 \**************************************************************************/
908
909 /*
910 * Checksum: This is 'optional'. It's quite likely also a good
911 * candidate for assembler hackery 8)
912 */
913 static unsigned long atalk_sum_partial(const unsigned char *data,
914 int len, unsigned long sum)
915 {
916 /* This ought to be unwrapped neatly. I'll trust gcc for now */
917 while (len--) {
918 sum += *data++;
919 sum = rol16(sum, 1);
920 }
921 return sum;
922 }
923
924 /* Checksum skb data -- similar to skb_checksum */
925 static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset,
926 int len, unsigned long sum)
927 {
928 int start = skb_headlen(skb);
929 struct sk_buff *frag_iter;
930 int i, copy;
931
932 /* checksum stuff in header space */
933 if ((copy = start - offset) > 0) {
934 if (copy > len)
935 copy = len;
936 sum = atalk_sum_partial(skb->data + offset, copy, sum);
937 if ((len -= copy) == 0)
938 return sum;
939
940 offset += copy;
941 }
942
943 /* checksum stuff in frags */
944 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
945 int end;
946 const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
947 WARN_ON(start > offset + len);
948
949 end = start + skb_frag_size(frag);
950 if ((copy = end - offset) > 0) {
951 u8 *vaddr;
952
953 if (copy > len)
954 copy = len;
955 vaddr = kmap_atomic(skb_frag_page(frag));
956 sum = atalk_sum_partial(vaddr + skb_frag_off(frag) +
957 offset - start, copy, sum);
958 kunmap_atomic(vaddr);
959
960 if (!(len -= copy))
961 return sum;
962 offset += copy;
963 }
964 start = end;
965 }
966
967 skb_walk_frags(skb, frag_iter) {
968 int end;
969
970 WARN_ON(start > offset + len);
971
972 end = start + frag_iter->len;
973 if ((copy = end - offset) > 0) {
974 if (copy > len)
975 copy = len;
976 sum = atalk_sum_skb(frag_iter, offset - start,
977 copy, sum);
978 if ((len -= copy) == 0)
979 return sum;
980 offset += copy;
981 }
982 start = end;
983 }
984
985 BUG_ON(len > 0);
986
987 return sum;
988 }
989
990 static __be16 atalk_checksum(const struct sk_buff *skb, int len)
991 {
992 unsigned long sum;
993
994 /* skip header 4 bytes */
995 sum = atalk_sum_skb(skb, 4, len-4, 0);
996
997 /* Use 0xFFFF for 0. 0 itself means none */
998 return sum ? htons((unsigned short)sum) : htons(0xFFFF);
999 }
1000
1001 static struct proto ddp_proto = {
1002 .name = "DDP",
1003 .owner = THIS_MODULE,
1004 .obj_size = sizeof(struct atalk_sock),
1005 };
1006
1007 /*
1008 * Create a socket. Initialise the socket, blank the addresses
1009 * set the state.
1010 */
1011 static int atalk_create(struct net *net, struct socket *sock, int protocol,
1012 int kern)
1013 {
1014 struct sock *sk;
1015 int rc = -ESOCKTNOSUPPORT;
1016
1017 if (!net_eq(net, &init_net))
1018 return -EAFNOSUPPORT;
1019
1020 /*
1021 * We permit SOCK_DGRAM and RAW is an extension. It is trivial to do
1022 * and gives you the full ELAP frame. Should be handy for CAP 8)
1023 */
1024 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
1025 goto out;
1026
1027 rc = -EPERM;
1028 if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
1029 goto out;
1030
1031 rc = -ENOMEM;
1032 sk = sk_alloc(net, PF_APPLETALK, GFP_KERNEL, &ddp_proto, kern);
1033 if (!sk)
1034 goto out;
1035 rc = 0;
1036 sock->ops = &atalk_dgram_ops;
1037 sock_init_data(sock, sk);
1038
1039 /* Checksums on by default */
1040 sock_set_flag(sk, SOCK_ZAPPED);
1041 out:
1042 return rc;
1043 }
1044
1045 /* Free a socket. No work needed */
1046 static int atalk_release(struct socket *sock)
1047 {
1048 struct sock *sk = sock->sk;
1049
1050 if (sk) {
1051 sock_hold(sk);
1052 lock_sock(sk);
1053
1054 sock_orphan(sk);
1055 sock->sk = NULL;
1056 atalk_destroy_socket(sk);
1057
1058 release_sock(sk);
1059 sock_put(sk);
1060 }
1061 return 0;
1062 }
1063
1064 /**
1065 * atalk_pick_and_bind_port - Pick a source port when one is not given
1066 * @sk: socket to insert into the tables
1067 * @sat: address to search for
1068 *
1069 * Pick a source port when one is not given. If we can find a suitable free
1070 * one, we insert the socket into the tables using it.
1071 *
1072 * This whole operation must be atomic.
1073 */
1074 static int atalk_pick_and_bind_port(struct sock *sk, struct sockaddr_at *sat)
1075 {
1076 int retval;
1077
1078 write_lock_bh(&atalk_sockets_lock);
1079
1080 for (sat->sat_port = ATPORT_RESERVED;
1081 sat->sat_port < ATPORT_LAST;
1082 sat->sat_port++) {
1083 struct sock *s;
1084
1085 sk_for_each(s, &atalk_sockets) {
1086 struct atalk_sock *at = at_sk(s);
1087
1088 if (at->src_net == sat->sat_addr.s_net &&
1089 at->src_node == sat->sat_addr.s_node &&
1090 at->src_port == sat->sat_port)
1091 goto try_next_port;
1092 }
1093
1094 /* Wheee, it's free, assign and insert. */
1095 __atalk_insert_socket(sk);
1096 at_sk(sk)->src_port = sat->sat_port;
1097 retval = 0;
1098 goto out;
1099
1100 try_next_port:;
1101 }
1102
1103 retval = -EBUSY;
1104 out:
1105 write_unlock_bh(&atalk_sockets_lock);
1106 return retval;
1107 }
1108
1109 static int atalk_autobind(struct sock *sk)
1110 {
1111 struct atalk_sock *at = at_sk(sk);
1112 struct sockaddr_at sat;
1113 struct atalk_addr *ap = atalk_find_primary();
1114 int n = -EADDRNOTAVAIL;
1115
1116 if (!ap || ap->s_net == htons(ATADDR_ANYNET))
1117 goto out;
1118
1119 at->src_net = sat.sat_addr.s_net = ap->s_net;
1120 at->src_node = sat.sat_addr.s_node = ap->s_node;
1121
1122 n = atalk_pick_and_bind_port(sk, &sat);
1123 if (!n)
1124 sock_reset_flag(sk, SOCK_ZAPPED);
1125 out:
1126 return n;
1127 }
1128
1129 /* Set the address 'our end' of the connection */
1130 static int atalk_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
1131 {
1132 struct sockaddr_at *addr = (struct sockaddr_at *)uaddr;
1133 struct sock *sk = sock->sk;
1134 struct atalk_sock *at = at_sk(sk);
1135 int err;
1136
1137 if (!sock_flag(sk, SOCK_ZAPPED) ||
1138 addr_len != sizeof(struct sockaddr_at))
1139 return -EINVAL;
1140
1141 if (addr->sat_family != AF_APPLETALK)
1142 return -EAFNOSUPPORT;
1143
1144 lock_sock(sk);
1145 if (addr->sat_addr.s_net == htons(ATADDR_ANYNET)) {
1146 struct atalk_addr *ap = atalk_find_primary();
1147
1148 err = -EADDRNOTAVAIL;
1149 if (!ap)
1150 goto out;
1151
1152 at->src_net = addr->sat_addr.s_net = ap->s_net;
1153 at->src_node = addr->sat_addr.s_node = ap->s_node;
1154 } else {
1155 err = -EADDRNOTAVAIL;
1156 if (!atalk_find_interface(addr->sat_addr.s_net,
1157 addr->sat_addr.s_node))
1158 goto out;
1159
1160 at->src_net = addr->sat_addr.s_net;
1161 at->src_node = addr->sat_addr.s_node;
1162 }
1163
1164 if (addr->sat_port == ATADDR_ANYPORT) {
1165 err = atalk_pick_and_bind_port(sk, addr);
1166
1167 if (err < 0)
1168 goto out;
1169 } else {
1170 at->src_port = addr->sat_port;
1171
1172 err = -EADDRINUSE;
1173 if (atalk_find_or_insert_socket(sk, addr))
1174 goto out;
1175 }
1176
1177 sock_reset_flag(sk, SOCK_ZAPPED);
1178 err = 0;
1179 out:
1180 release_sock(sk);
1181 return err;
1182 }
1183
1184 /* Set the address we talk to */
1185 static int atalk_connect(struct socket *sock, struct sockaddr *uaddr,
1186 int addr_len, int flags)
1187 {
1188 struct sock *sk = sock->sk;
1189 struct atalk_sock *at = at_sk(sk);
1190 struct sockaddr_at *addr;
1191 int err;
1192
1193 sk->sk_state = TCP_CLOSE;
1194 sock->state = SS_UNCONNECTED;
1195
1196 if (addr_len != sizeof(*addr))
1197 return -EINVAL;
1198
1199 addr = (struct sockaddr_at *)uaddr;
1200
1201 if (addr->sat_family != AF_APPLETALK)
1202 return -EAFNOSUPPORT;
1203
1204 if (addr->sat_addr.s_node == ATADDR_BCAST &&
1205 !sock_flag(sk, SOCK_BROADCAST)) {
1206 #if 1
1207 pr_warn("atalk_connect: %s is broken and did not set SO_BROADCAST.\n",
1208 current->comm);
1209 #else
1210 return -EACCES;
1211 #endif
1212 }
1213
1214 lock_sock(sk);
1215 err = -EBUSY;
1216 if (sock_flag(sk, SOCK_ZAPPED))
1217 if (atalk_autobind(sk) < 0)
1218 goto out;
1219
1220 err = -ENETUNREACH;
1221 if (!atrtr_get_dev(&addr->sat_addr))
1222 goto out;
1223
1224 at->dest_port = addr->sat_port;
1225 at->dest_net = addr->sat_addr.s_net;
1226 at->dest_node = addr->sat_addr.s_node;
1227
1228 sock->state = SS_CONNECTED;
1229 sk->sk_state = TCP_ESTABLISHED;
1230 err = 0;
1231 out:
1232 release_sock(sk);
1233 return err;
1234 }
1235
1236 /*
1237 * Find the name of an AppleTalk socket. Just copy the right
1238 * fields into the sockaddr.
1239 */
1240 static int atalk_getname(struct socket *sock, struct sockaddr *uaddr,
1241 int peer)
1242 {
1243 struct sockaddr_at sat;
1244 struct sock *sk = sock->sk;
1245 struct atalk_sock *at = at_sk(sk);
1246 int err;
1247
1248 lock_sock(sk);
1249 err = -ENOBUFS;
1250 if (sock_flag(sk, SOCK_ZAPPED))
1251 if (atalk_autobind(sk) < 0)
1252 goto out;
1253
1254 memset(&sat, 0, sizeof(sat));
1255
1256 if (peer) {
1257 err = -ENOTCONN;
1258 if (sk->sk_state != TCP_ESTABLISHED)
1259 goto out;
1260
1261 sat.sat_addr.s_net = at->dest_net;
1262 sat.sat_addr.s_node = at->dest_node;
1263 sat.sat_port = at->dest_port;
1264 } else {
1265 sat.sat_addr.s_net = at->src_net;
1266 sat.sat_addr.s_node = at->src_node;
1267 sat.sat_port = at->src_port;
1268 }
1269
1270 sat.sat_family = AF_APPLETALK;
1271 memcpy(uaddr, &sat, sizeof(sat));
1272 err = sizeof(struct sockaddr_at);
1273
1274 out:
1275 release_sock(sk);
1276 return err;
1277 }
1278
1279 #if IS_ENABLED(CONFIG_IPDDP)
1280 static __inline__ int is_ip_over_ddp(struct sk_buff *skb)
1281 {
1282 return skb->data[12] == 22;
1283 }
1284
1285 static int handle_ip_over_ddp(struct sk_buff *skb)
1286 {
1287 struct net_device *dev = __dev_get_by_name(&init_net, "ipddp0");
1288 struct net_device_stats *stats;
1289
1290 /* This needs to be able to handle ipddp"N" devices */
1291 if (!dev) {
1292 kfree_skb(skb);
1293 return NET_RX_DROP;
1294 }
1295
1296 skb->protocol = htons(ETH_P_IP);
1297 skb_pull(skb, 13);
1298 skb->dev = dev;
1299 skb_reset_transport_header(skb);
1300
1301 stats = netdev_priv(dev);
1302 stats->rx_packets++;
1303 stats->rx_bytes += skb->len + 13;
1304 return netif_rx(skb); /* Send the SKB up to a higher place. */
1305 }
1306 #else
1307 /* make it easy for gcc to optimize this test out, i.e. kill the code */
1308 #define is_ip_over_ddp(skb) 0
1309 #define handle_ip_over_ddp(skb) 0
1310 #endif
1311
1312 static int atalk_route_packet(struct sk_buff *skb, struct net_device *dev,
1313 struct ddpehdr *ddp, __u16 len_hops, int origlen)
1314 {
1315 struct atalk_route *rt;
1316 struct atalk_addr ta;
1317
1318 /*
1319 * Don't route multicast, etc., packets, or packets sent to "this
1320 * network"
1321 */
1322 if (skb->pkt_type != PACKET_HOST || !ddp->deh_dnet) {
1323 /*
1324 * FIXME:
1325 *
1326 * Can it ever happen that a packet is from a PPP iface and
1327 * needs to be broadcast onto the default network?
1328 */
1329 if (dev->type == ARPHRD_PPP)
1330 printk(KERN_DEBUG "AppleTalk: didn't forward broadcast "
1331 "packet received from PPP iface\n");
1332 goto free_it;
1333 }
1334
1335 ta.s_net = ddp->deh_dnet;
1336 ta.s_node = ddp->deh_dnode;
1337
1338 /* Route the packet */
1339 rt = atrtr_find(&ta);
1340 /* increment hops count */
1341 len_hops += 1 << 10;
1342 if (!rt || !(len_hops & (15 << 10)))
1343 goto free_it;
1344
1345 /* FIXME: use skb->cb to be able to use shared skbs */
1346
1347 /*
1348 * Route goes through another gateway, so set the target to the
1349 * gateway instead.
1350 */
1351
1352 if (rt->flags & RTF_GATEWAY) {
1353 ta.s_net = rt->gateway.s_net;
1354 ta.s_node = rt->gateway.s_node;
1355 }
1356
1357 /* Fix up skb->len field */
1358 skb_trim(skb, min_t(unsigned int, origlen,
1359 (rt->dev->hard_header_len +
1360 ddp_dl->header_length + (len_hops & 1023))));
1361
1362 /* FIXME: use skb->cb to be able to use shared skbs */
1363 ddp->deh_len_hops = htons(len_hops);
1364
1365 /*
1366 * Send the buffer onwards
1367 *
1368 * Now we must always be careful. If it's come from LocalTalk to
1369 * EtherTalk it might not fit
1370 *
1371 * Order matters here: If a packet has to be copied to make a new
1372 * headroom (rare hopefully) then it won't need unsharing.
1373 *
1374 * Note. ddp-> becomes invalid at the realloc.
1375 */
1376 if (skb_headroom(skb) < 22) {
1377 /* 22 bytes - 12 ether, 2 len, 3 802.2 5 snap */
1378 struct sk_buff *nskb = skb_realloc_headroom(skb, 32);
1379 kfree_skb(skb);
1380 skb = nskb;
1381 } else
1382 skb = skb_unshare(skb, GFP_ATOMIC);
1383
1384 /*
1385 * If the buffer didn't vanish into the lack of space bitbucket we can
1386 * send it.
1387 */
1388 if (skb == NULL)
1389 goto drop;
1390
1391 if (aarp_send_ddp(rt->dev, skb, &ta, NULL) == NET_XMIT_DROP)
1392 return NET_RX_DROP;
1393 return NET_RX_SUCCESS;
1394 free_it:
1395 kfree_skb(skb);
1396 drop:
1397 return NET_RX_DROP;
1398 }
1399
1400 /**
1401 * atalk_rcv - Receive a packet (in skb) from device dev
1402 * @skb - packet received
1403 * @dev - network device where the packet comes from
1404 * @pt - packet type
1405 *
1406 * Receive a packet (in skb) from device dev. This has come from the SNAP
1407 * decoder, and on entry skb->transport_header is the DDP header, skb->len
1408 * is the DDP header, skb->len is the DDP length. The physical headers
1409 * have been extracted. PPP should probably pass frames marked as for this
1410 * layer. [ie ARPHRD_ETHERTALK]
1411 */
1412 static int atalk_rcv(struct sk_buff *skb, struct net_device *dev,
1413 struct packet_type *pt, struct net_device *orig_dev)
1414 {
1415 struct ddpehdr *ddp;
1416 struct sock *sock;
1417 struct atalk_iface *atif;
1418 struct sockaddr_at tosat;
1419 int origlen;
1420 __u16 len_hops;
1421
1422 if (!net_eq(dev_net(dev), &init_net))
1423 goto drop;
1424
1425 /* Don't mangle buffer if shared */
1426 if (!(skb = skb_share_check(skb, GFP_ATOMIC)))
1427 goto out;
1428
1429 /* Size check and make sure header is contiguous */
1430 if (!pskb_may_pull(skb, sizeof(*ddp)))
1431 goto drop;
1432
1433 ddp = ddp_hdr(skb);
1434
1435 len_hops = ntohs(ddp->deh_len_hops);
1436
1437 /* Trim buffer in case of stray trailing data */
1438 origlen = skb->len;
1439 skb_trim(skb, min_t(unsigned int, skb->len, len_hops & 1023));
1440
1441 /*
1442 * Size check to see if ddp->deh_len was crap
1443 * (Otherwise we'll detonate most spectacularly
1444 * in the middle of atalk_checksum() or recvmsg()).
1445 */
1446 if (skb->len < sizeof(*ddp) || skb->len < (len_hops & 1023)) {
1447 pr_debug("AppleTalk: dropping corrupted frame (deh_len=%u, "
1448 "skb->len=%u)\n", len_hops & 1023, skb->len);
1449 goto drop;
1450 }
1451
1452 /*
1453 * Any checksums. Note we don't do htons() on this == is assumed to be
1454 * valid for net byte orders all over the networking code...
1455 */
1456 if (ddp->deh_sum &&
1457 atalk_checksum(skb, len_hops & 1023) != ddp->deh_sum)
1458 /* Not a valid AppleTalk frame - dustbin time */
1459 goto drop;
1460
1461 /* Check the packet is aimed at us */
1462 if (!ddp->deh_dnet) /* Net 0 is 'this network' */
1463 atif = atalk_find_anynet(ddp->deh_dnode, dev);
1464 else
1465 atif = atalk_find_interface(ddp->deh_dnet, ddp->deh_dnode);
1466
1467 if (!atif) {
1468 /* Not ours, so we route the packet via the correct
1469 * AppleTalk iface
1470 */
1471 return atalk_route_packet(skb, dev, ddp, len_hops, origlen);
1472 }
1473
1474 /* if IP over DDP is not selected this code will be optimized out */
1475 if (is_ip_over_ddp(skb))
1476 return handle_ip_over_ddp(skb);
1477 /*
1478 * Which socket - atalk_search_socket() looks for a *full match*
1479 * of the <net, node, port> tuple.
1480 */
1481 tosat.sat_addr.s_net = ddp->deh_dnet;
1482 tosat.sat_addr.s_node = ddp->deh_dnode;
1483 tosat.sat_port = ddp->deh_dport;
1484
1485 sock = atalk_search_socket(&tosat, atif);
1486 if (!sock) /* But not one of our sockets */
1487 goto drop;
1488
1489 /* Queue packet (standard) */
1490 if (sock_queue_rcv_skb(sock, skb) < 0)
1491 goto drop;
1492
1493 return NET_RX_SUCCESS;
1494
1495 drop:
1496 kfree_skb(skb);
1497 out:
1498 return NET_RX_DROP;
1499
1500 }
1501
1502 /*
1503 * Receive a LocalTalk frame. We make some demands on the caller here.
1504 * Caller must provide enough headroom on the packet to pull the short
1505 * header and append a long one.
1506 */
1507 static int ltalk_rcv(struct sk_buff *skb, struct net_device *dev,
1508 struct packet_type *pt, struct net_device *orig_dev)
1509 {
1510 if (!net_eq(dev_net(dev), &init_net))
1511 goto freeit;
1512
1513 /* Expand any short form frames */
1514 if (skb_mac_header(skb)[2] == 1) {
1515 struct ddpehdr *ddp;
1516 /* Find our address */
1517 struct atalk_addr *ap = atalk_find_dev_addr(dev);
1518
1519 if (!ap || skb->len < sizeof(__be16) || skb->len > 1023)
1520 goto freeit;
1521
1522 /* Don't mangle buffer if shared */
1523 if (!(skb = skb_share_check(skb, GFP_ATOMIC)))
1524 return 0;
1525
1526 /*
1527 * The push leaves us with a ddephdr not an shdr, and
1528 * handily the port bytes in the right place preset.
1529 */
1530 ddp = skb_push(skb, sizeof(*ddp) - 4);
1531
1532 /* Now fill in the long header */
1533
1534 /*
1535 * These two first. The mac overlays the new source/dest
1536 * network information so we MUST copy these before
1537 * we write the network numbers !
1538 */
1539
1540 ddp->deh_dnode = skb_mac_header(skb)[0]; /* From physical header */
1541 ddp->deh_snode = skb_mac_header(skb)[1]; /* From physical header */
1542
1543 ddp->deh_dnet = ap->s_net; /* Network number */
1544 ddp->deh_snet = ap->s_net;
1545 ddp->deh_sum = 0; /* No checksum */
1546 /*
1547 * Not sure about this bit...
1548 */
1549 /* Non routable, so force a drop if we slip up later */
1550 ddp->deh_len_hops = htons(skb->len + (DDP_MAXHOPS << 10));
1551 }
1552 skb_reset_transport_header(skb);
1553
1554 return atalk_rcv(skb, dev, pt, orig_dev);
1555 freeit:
1556 kfree_skb(skb);
1557 return 0;
1558 }
1559
1560 static int atalk_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1561 {
1562 struct sock *sk = sock->sk;
1563 struct atalk_sock *at = at_sk(sk);
1564 DECLARE_SOCKADDR(struct sockaddr_at *, usat, msg->msg_name);
1565 int flags = msg->msg_flags;
1566 int loopback = 0;
1567 struct sockaddr_at local_satalk, gsat;
1568 struct sk_buff *skb;
1569 struct net_device *dev;
1570 struct ddpehdr *ddp;
1571 int size;
1572 struct atalk_route *rt;
1573 int err;
1574
1575 if (flags & ~(MSG_DONTWAIT|MSG_CMSG_COMPAT))
1576 return -EINVAL;
1577
1578 if (len > DDP_MAXSZ)
1579 return -EMSGSIZE;
1580
1581 lock_sock(sk);
1582 if (usat) {
1583 err = -EBUSY;
1584 if (sock_flag(sk, SOCK_ZAPPED))
1585 if (atalk_autobind(sk) < 0)
1586 goto out;
1587
1588 err = -EINVAL;
1589 if (msg->msg_namelen < sizeof(*usat) ||
1590 usat->sat_family != AF_APPLETALK)
1591 goto out;
1592
1593 err = -EPERM;
1594 /* netatalk didn't implement this check */
1595 if (usat->sat_addr.s_node == ATADDR_BCAST &&
1596 !sock_flag(sk, SOCK_BROADCAST)) {
1597 goto out;
1598 }
1599 } else {
1600 err = -ENOTCONN;
1601 if (sk->sk_state != TCP_ESTABLISHED)
1602 goto out;
1603 usat = &local_satalk;
1604 usat->sat_family = AF_APPLETALK;
1605 usat->sat_port = at->dest_port;
1606 usat->sat_addr.s_node = at->dest_node;
1607 usat->sat_addr.s_net = at->dest_net;
1608 }
1609
1610 /* Build a packet */
1611 SOCK_DEBUG(sk, "SK %p: Got address.\n", sk);
1612
1613 /* For headers */
1614 size = sizeof(struct ddpehdr) + len + ddp_dl->header_length;
1615
1616 if (usat->sat_addr.s_net || usat->sat_addr.s_node == ATADDR_ANYNODE) {
1617 rt = atrtr_find(&usat->sat_addr);
1618 } else {
1619 struct atalk_addr at_hint;
1620
1621 at_hint.s_node = 0;
1622 at_hint.s_net = at->src_net;
1623
1624 rt = atrtr_find(&at_hint);
1625 }
1626 err = -ENETUNREACH;
1627 if (!rt)
1628 goto out;
1629
1630 dev = rt->dev;
1631
1632 SOCK_DEBUG(sk, "SK %p: Size needed %d, device %s\n",
1633 sk, size, dev->name);
1634
1635 size += dev->hard_header_len;
1636 release_sock(sk);
1637 skb = sock_alloc_send_skb(sk, size, (flags & MSG_DONTWAIT), &err);
1638 lock_sock(sk);
1639 if (!skb)
1640 goto out;
1641
1642 skb_reserve(skb, ddp_dl->header_length);
1643 skb_reserve(skb, dev->hard_header_len);
1644 skb->dev = dev;
1645
1646 SOCK_DEBUG(sk, "SK %p: Begin build.\n", sk);
1647
1648 ddp = skb_put(skb, sizeof(struct ddpehdr));
1649 ddp->deh_len_hops = htons(len + sizeof(*ddp));
1650 ddp->deh_dnet = usat->sat_addr.s_net;
1651 ddp->deh_snet = at->src_net;
1652 ddp->deh_dnode = usat->sat_addr.s_node;
1653 ddp->deh_snode = at->src_node;
1654 ddp->deh_dport = usat->sat_port;
1655 ddp->deh_sport = at->src_port;
1656
1657 SOCK_DEBUG(sk, "SK %p: Copy user data (%zd bytes).\n", sk, len);
1658
1659 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1660 if (err) {
1661 kfree_skb(skb);
1662 err = -EFAULT;
1663 goto out;
1664 }
1665
1666 if (sk->sk_no_check_tx)
1667 ddp->deh_sum = 0;
1668 else
1669 ddp->deh_sum = atalk_checksum(skb, len + sizeof(*ddp));
1670
1671 /*
1672 * Loopback broadcast packets to non gateway targets (ie routes
1673 * to group we are in)
1674 */
1675 if (ddp->deh_dnode == ATADDR_BCAST &&
1676 !(rt->flags & RTF_GATEWAY) && !(dev->flags & IFF_LOOPBACK)) {
1677 struct sk_buff *skb2 = skb_copy(skb, GFP_KERNEL);
1678
1679 if (skb2) {
1680 loopback = 1;
1681 SOCK_DEBUG(sk, "SK %p: send out(copy).\n", sk);
1682 /*
1683 * If it fails it is queued/sent above in the aarp queue
1684 */
1685 aarp_send_ddp(dev, skb2, &usat->sat_addr, NULL);
1686 }
1687 }
1688
1689 if (dev->flags & IFF_LOOPBACK || loopback) {
1690 SOCK_DEBUG(sk, "SK %p: Loop back.\n", sk);
1691 /* loop back */
1692 skb_orphan(skb);
1693 if (ddp->deh_dnode == ATADDR_BCAST) {
1694 struct atalk_addr at_lo;
1695
1696 at_lo.s_node = 0;
1697 at_lo.s_net = 0;
1698
1699 rt = atrtr_find(&at_lo);
1700 if (!rt) {
1701 kfree_skb(skb);
1702 err = -ENETUNREACH;
1703 goto out;
1704 }
1705 dev = rt->dev;
1706 skb->dev = dev;
1707 }
1708 ddp_dl->request(ddp_dl, skb, dev->dev_addr);
1709 } else {
1710 SOCK_DEBUG(sk, "SK %p: send out.\n", sk);
1711 if (rt->flags & RTF_GATEWAY) {
1712 gsat.sat_addr = rt->gateway;
1713 usat = &gsat;
1714 }
1715
1716 /*
1717 * If it fails it is queued/sent above in the aarp queue
1718 */
1719 aarp_send_ddp(dev, skb, &usat->sat_addr, NULL);
1720 }
1721 SOCK_DEBUG(sk, "SK %p: Done write (%zd).\n", sk, len);
1722
1723 out:
1724 release_sock(sk);
1725 return err ? : len;
1726 }
1727
1728 static int atalk_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1729 int flags)
1730 {
1731 struct sock *sk = sock->sk;
1732 struct ddpehdr *ddp;
1733 int copied = 0;
1734 int offset = 0;
1735 int err = 0;
1736 struct sk_buff *skb;
1737
1738 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1739 flags & MSG_DONTWAIT, &err);
1740 lock_sock(sk);
1741
1742 if (!skb)
1743 goto out;
1744
1745 /* FIXME: use skb->cb to be able to use shared skbs */
1746 ddp = ddp_hdr(skb);
1747 copied = ntohs(ddp->deh_len_hops) & 1023;
1748
1749 if (sk->sk_type != SOCK_RAW) {
1750 offset = sizeof(*ddp);
1751 copied -= offset;
1752 }
1753
1754 if (copied > size) {
1755 copied = size;
1756 msg->msg_flags |= MSG_TRUNC;
1757 }
1758 err = skb_copy_datagram_msg(skb, offset, msg, copied);
1759
1760 if (!err && msg->msg_name) {
1761 DECLARE_SOCKADDR(struct sockaddr_at *, sat, msg->msg_name);
1762 sat->sat_family = AF_APPLETALK;
1763 sat->sat_port = ddp->deh_sport;
1764 sat->sat_addr.s_node = ddp->deh_snode;
1765 sat->sat_addr.s_net = ddp->deh_snet;
1766 msg->msg_namelen = sizeof(*sat);
1767 }
1768
1769 skb_free_datagram(sk, skb); /* Free the datagram. */
1770
1771 out:
1772 release_sock(sk);
1773 return err ? : copied;
1774 }
1775
1776
1777 /*
1778 * AppleTalk ioctl calls.
1779 */
1780 static int atalk_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1781 {
1782 int rc = -ENOIOCTLCMD;
1783 struct sock *sk = sock->sk;
1784 void __user *argp = (void __user *)arg;
1785
1786 switch (cmd) {
1787 /* Protocol layer */
1788 case TIOCOUTQ: {
1789 long amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1790
1791 if (amount < 0)
1792 amount = 0;
1793 rc = put_user(amount, (int __user *)argp);
1794 break;
1795 }
1796 case TIOCINQ: {
1797 /*
1798 * These two are safe on a single CPU system as only
1799 * user tasks fiddle here
1800 */
1801 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
1802 long amount = 0;
1803
1804 if (skb)
1805 amount = skb->len - sizeof(struct ddpehdr);
1806 rc = put_user(amount, (int __user *)argp);
1807 break;
1808 }
1809 /* Routing */
1810 case SIOCADDRT:
1811 case SIOCDELRT:
1812 rc = -EPERM;
1813 if (capable(CAP_NET_ADMIN))
1814 rc = atrtr_ioctl(cmd, argp);
1815 break;
1816 /* Interface */
1817 case SIOCGIFADDR:
1818 case SIOCSIFADDR:
1819 case SIOCGIFBRDADDR:
1820 case SIOCATALKDIFADDR:
1821 case SIOCDIFADDR:
1822 case SIOCSARP: /* proxy AARP */
1823 case SIOCDARP: /* proxy AARP */
1824 rtnl_lock();
1825 rc = atif_ioctl(cmd, argp);
1826 rtnl_unlock();
1827 break;
1828 }
1829
1830 return rc;
1831 }
1832
1833
1834 #ifdef CONFIG_COMPAT
1835 static int atalk_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1836 {
1837 /*
1838 * SIOCATALKDIFADDR is a SIOCPROTOPRIVATE ioctl number, so we
1839 * cannot handle it in common code. The data we access if ifreq
1840 * here is compatible, so we can simply call the native
1841 * handler.
1842 */
1843 if (cmd == SIOCATALKDIFADDR)
1844 return atalk_ioctl(sock, cmd, (unsigned long)compat_ptr(arg));
1845
1846 return -ENOIOCTLCMD;
1847 }
1848 #endif
1849
1850
1851 static const struct net_proto_family atalk_family_ops = {
1852 .family = PF_APPLETALK,
1853 .create = atalk_create,
1854 .owner = THIS_MODULE,
1855 };
1856
1857 static const struct proto_ops atalk_dgram_ops = {
1858 .family = PF_APPLETALK,
1859 .owner = THIS_MODULE,
1860 .release = atalk_release,
1861 .bind = atalk_bind,
1862 .connect = atalk_connect,
1863 .socketpair = sock_no_socketpair,
1864 .accept = sock_no_accept,
1865 .getname = atalk_getname,
1866 .poll = datagram_poll,
1867 .ioctl = atalk_ioctl,
1868 .gettstamp = sock_gettstamp,
1869 #ifdef CONFIG_COMPAT
1870 .compat_ioctl = atalk_compat_ioctl,
1871 #endif
1872 .listen = sock_no_listen,
1873 .shutdown = sock_no_shutdown,
1874 .setsockopt = sock_no_setsockopt,
1875 .getsockopt = sock_no_getsockopt,
1876 .sendmsg = atalk_sendmsg,
1877 .recvmsg = atalk_recvmsg,
1878 .mmap = sock_no_mmap,
1879 .sendpage = sock_no_sendpage,
1880 };
1881
1882 static struct notifier_block ddp_notifier = {
1883 .notifier_call = ddp_device_event,
1884 };
1885
1886 static struct packet_type ltalk_packet_type __read_mostly = {
1887 .type = cpu_to_be16(ETH_P_LOCALTALK),
1888 .func = ltalk_rcv,
1889 };
1890
1891 static struct packet_type ppptalk_packet_type __read_mostly = {
1892 .type = cpu_to_be16(ETH_P_PPPTALK),
1893 .func = atalk_rcv,
1894 };
1895
1896 static unsigned char ddp_snap_id[] = { 0x08, 0x00, 0x07, 0x80, 0x9B };
1897
1898 /* Export symbols for use by drivers when AppleTalk is a module */
1899 EXPORT_SYMBOL(atrtr_get_dev);
1900 EXPORT_SYMBOL(atalk_find_dev_addr);
1901
1902 /* Called by proto.c on kernel start up */
1903 static int __init atalk_init(void)
1904 {
1905 int rc;
1906
1907 rc = proto_register(&ddp_proto, 0);
1908 if (rc)
1909 goto out;
1910
1911 rc = sock_register(&atalk_family_ops);
1912 if (rc)
1913 goto out_proto;
1914
1915 ddp_dl = register_snap_client(ddp_snap_id, atalk_rcv);
1916 if (!ddp_dl) {
1917 pr_crit("Unable to register DDP with SNAP.\n");
1918 rc = -ENOMEM;
1919 goto out_sock;
1920 }
1921
1922 dev_add_pack(&ltalk_packet_type);
1923 dev_add_pack(&ppptalk_packet_type);
1924
1925 rc = register_netdevice_notifier(&ddp_notifier);
1926 if (rc)
1927 goto out_snap;
1928
1929 rc = aarp_proto_init();
1930 if (rc)
1931 goto out_dev;
1932
1933 rc = atalk_proc_init();
1934 if (rc)
1935 goto out_aarp;
1936
1937 rc = atalk_register_sysctl();
1938 if (rc)
1939 goto out_proc;
1940 out:
1941 return rc;
1942 out_proc:
1943 atalk_proc_exit();
1944 out_aarp:
1945 aarp_cleanup_module();
1946 out_dev:
1947 unregister_netdevice_notifier(&ddp_notifier);
1948 out_snap:
1949 dev_remove_pack(&ppptalk_packet_type);
1950 dev_remove_pack(&ltalk_packet_type);
1951 unregister_snap_client(ddp_dl);
1952 out_sock:
1953 sock_unregister(PF_APPLETALK);
1954 out_proto:
1955 proto_unregister(&ddp_proto);
1956 goto out;
1957 }
1958 module_init(atalk_init);
1959
1960 /*
1961 * No explicit module reference count manipulation is needed in the
1962 * protocol. Socket layer sets module reference count for us
1963 * and interfaces reference counting is done
1964 * by the network device layer.
1965 *
1966 * Ergo, before the AppleTalk module can be removed, all AppleTalk
1967 * sockets be closed from user space.
1968 */
1969 static void __exit atalk_exit(void)
1970 {
1971 #ifdef CONFIG_SYSCTL
1972 atalk_unregister_sysctl();
1973 #endif /* CONFIG_SYSCTL */
1974 atalk_proc_exit();
1975 aarp_cleanup_module(); /* General aarp clean-up. */
1976 unregister_netdevice_notifier(&ddp_notifier);
1977 dev_remove_pack(&ltalk_packet_type);
1978 dev_remove_pack(&ppptalk_packet_type);
1979 unregister_snap_client(ddp_dl);
1980 sock_unregister(PF_APPLETALK);
1981 proto_unregister(&ddp_proto);
1982 }
1983 module_exit(atalk_exit);
1984
1985 MODULE_LICENSE("GPL");
1986 MODULE_AUTHOR("Alan Cox <alan@lxorguk.ukuu.org.uk>");
1987 MODULE_DESCRIPTION("AppleTalk 0.20\n");
1988 MODULE_ALIAS_NETPROTO(PF_APPLETALK);
Linux with added FPC-III support