1 // SPDX-License-Identifier: GPL-2.0-only
2 /* net/atm/clip.c - RFC1577 Classical IP over ATM */
3
4 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
5
6 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
7
8 #include <linux/string.h>
9 #include <linux/errno.h>
10 #include <linux/kernel.h> /* for UINT_MAX */
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/netdevice.h>
14 #include <linux/skbuff.h>
15 #include <linux/wait.h>
16 #include <linux/timer.h>
17 #include <linux/if_arp.h> /* for some manifest constants */
18 #include <linux/notifier.h>
19 #include <linux/atm.h>
20 #include <linux/atmdev.h>
21 #include <linux/atmclip.h>
22 #include <linux/atmarp.h>
23 #include <linux/capability.h>
24 #include <linux/ip.h> /* for net/route.h */
25 #include <linux/in.h> /* for struct sockaddr_in */
26 #include <linux/if.h> /* for IFF_UP */
27 #include <linux/inetdevice.h>
28 #include <linux/bitops.h>
29 #include <linux/poison.h>
30 #include <linux/proc_fs.h>
31 #include <linux/seq_file.h>
32 #include <linux/rcupdate.h>
33 #include <linux/jhash.h>
34 #include <linux/slab.h>
35 #include <net/route.h> /* for struct rtable and routing */
36 #include <net/icmp.h> /* icmp_send */
37 #include <net/arp.h>
38 #include <linux/param.h> /* for HZ */
39 #include <linux/uaccess.h>
40 #include <asm/byteorder.h> /* for htons etc. */
41 #include <linux/atomic.h>
42
43 #include "common.h"
44 #include "resources.h"
45 #include <net/atmclip.h>
46
47 static struct net_device *clip_devs;
48 static struct atm_vcc *atmarpd;
49 static struct timer_list idle_timer;
50 static const struct neigh_ops clip_neigh_ops;
51
to_atmarpd(enum atmarp_ctrl_type type,int itf,__be32 ip)52 static int to_atmarpd(enum atmarp_ctrl_type type, int itf, __be32 ip)
53 {
54 struct sock *sk;
55 struct atmarp_ctrl *ctrl;
56 struct sk_buff *skb;
57
58 pr_debug("(%d)\n", type);
59 if (!atmarpd)
60 return -EUNATCH;
61 skb = alloc_skb(sizeof(struct atmarp_ctrl), GFP_ATOMIC);
62 if (!skb)
63 return -ENOMEM;
64 ctrl = skb_put(skb, sizeof(struct atmarp_ctrl));
65 ctrl->type = type;
66 ctrl->itf_num = itf;
67 ctrl->ip = ip;
68 atm_force_charge(atmarpd, skb->truesize);
69
70 sk = sk_atm(atmarpd);
71 skb_queue_tail(&sk->sk_receive_queue, skb);
72 sk->sk_data_ready(sk);
73 return 0;
74 }
75
link_vcc(struct clip_vcc * clip_vcc,struct atmarp_entry * entry)76 static void link_vcc(struct clip_vcc *clip_vcc, struct atmarp_entry *entry)
77 {
78 pr_debug("%p to entry %p (neigh %p)\n", clip_vcc, entry, entry->neigh);
79 clip_vcc->entry = entry;
80 clip_vcc->xoff = 0; /* @@@ may overrun buffer by one packet */
81 clip_vcc->next = entry->vccs;
82 entry->vccs = clip_vcc;
83 entry->neigh->used = jiffies;
84 }
85
unlink_clip_vcc(struct clip_vcc * clip_vcc)86 static void unlink_clip_vcc(struct clip_vcc *clip_vcc)
87 {
88 struct atmarp_entry *entry = clip_vcc->entry;
89 struct clip_vcc **walk;
90
91 if (!entry) {
92 pr_err("!clip_vcc->entry (clip_vcc %p)\n", clip_vcc);
93 return;
94 }
95 netif_tx_lock_bh(entry->neigh->dev); /* block clip_start_xmit() */
96 entry->neigh->used = jiffies;
97 for (walk = &entry->vccs; *walk; walk = &(*walk)->next)
98 if (*walk == clip_vcc) {
99 int error;
100
101 *walk = clip_vcc->next; /* atomic */
102 clip_vcc->entry = NULL;
103 if (clip_vcc->xoff)
104 netif_wake_queue(entry->neigh->dev);
105 if (entry->vccs)
106 goto out;
107 entry->expires = jiffies - 1;
108 /* force resolution or expiration */
109 error = neigh_update(entry->neigh, NULL, NUD_NONE,
110 NEIGH_UPDATE_F_ADMIN, 0);
111 if (error)
112 pr_err("neigh_update failed with %d\n", error);
113 goto out;
114 }
115 pr_err("ATMARP: failed (entry %p, vcc 0x%p)\n", entry, clip_vcc);
116 out:
117 netif_tx_unlock_bh(entry->neigh->dev);
118 }
119
120 /* The neighbour entry n->lock is held. */
neigh_check_cb(struct neighbour * n)121 static int neigh_check_cb(struct neighbour *n)
122 {
123 struct atmarp_entry *entry = neighbour_priv(n);
124 struct clip_vcc *cv;
125
126 if (n->ops != &clip_neigh_ops)
127 return 0;
128 for (cv = entry->vccs; cv; cv = cv->next) {
129 unsigned long exp = cv->last_use + cv->idle_timeout;
130
131 if (cv->idle_timeout && time_after(jiffies, exp)) {
132 pr_debug("releasing vcc %p->%p of entry %p\n",
133 cv, cv->vcc, entry);
134 vcc_release_async(cv->vcc, -ETIMEDOUT);
135 }
136 }
137
138 if (entry->vccs || time_before(jiffies, entry->expires))
139 return 0;
140
141 if (refcount_read(&n->refcnt) > 1) {
142 struct sk_buff *skb;
143
144 pr_debug("destruction postponed with ref %d\n",
145 refcount_read(&n->refcnt));
146
147 while ((skb = skb_dequeue(&n->arp_queue)) != NULL)
148 dev_kfree_skb(skb);
149
150 return 0;
151 }
152
153 pr_debug("expired neigh %p\n", n);
154 return 1;
155 }
156
idle_timer_check(struct timer_list * unused)157 static void idle_timer_check(struct timer_list *unused)
158 {
159 write_lock(&arp_tbl.lock);
160 __neigh_for_each_release(&arp_tbl, neigh_check_cb);
161 mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ);
162 write_unlock(&arp_tbl.lock);
163 }
164
clip_arp_rcv(struct sk_buff * skb)165 static int clip_arp_rcv(struct sk_buff *skb)
166 {
167 struct atm_vcc *vcc;
168
169 pr_debug("\n");
170 vcc = ATM_SKB(skb)->vcc;
171 if (!vcc || !atm_charge(vcc, skb->truesize)) {
172 dev_kfree_skb_any(skb);
173 return 0;
174 }
175 pr_debug("pushing to %p\n", vcc);
176 pr_debug("using %p\n", CLIP_VCC(vcc)->old_push);
177 CLIP_VCC(vcc)->old_push(vcc, skb);
178 return 0;
179 }
180
181 static const unsigned char llc_oui[] = {
182 0xaa, /* DSAP: non-ISO */
183 0xaa, /* SSAP: non-ISO */
184 0x03, /* Ctrl: Unnumbered Information Command PDU */
185 0x00, /* OUI: EtherType */
186 0x00,
187 0x00
188 };
189
clip_push(struct atm_vcc * vcc,struct sk_buff * skb)190 static void clip_push(struct atm_vcc *vcc, struct sk_buff *skb)
191 {
192 struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
193
194 pr_debug("\n");
195
196 if (!clip_devs) {
197 atm_return(vcc, skb->truesize);
198 kfree_skb(skb);
199 return;
200 }
201
202 if (!skb) {
203 pr_debug("removing VCC %p\n", clip_vcc);
204 if (clip_vcc->entry)
205 unlink_clip_vcc(clip_vcc);
206 clip_vcc->old_push(vcc, NULL); /* pass on the bad news */
207 kfree(clip_vcc);
208 return;
209 }
210 atm_return(vcc, skb->truesize);
211 skb->dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : clip_devs;
212 /* clip_vcc->entry == NULL if we don't have an IP address yet */
213 if (!skb->dev) {
214 dev_kfree_skb_any(skb);
215 return;
216 }
217 ATM_SKB(skb)->vcc = vcc;
218 skb_reset_mac_header(skb);
219 if (!clip_vcc->encap ||
220 skb->len < RFC1483LLC_LEN ||
221 memcmp(skb->data, llc_oui, sizeof(llc_oui)))
222 skb->protocol = htons(ETH_P_IP);
223 else {
224 skb->protocol = ((__be16 *)skb->data)[3];
225 skb_pull(skb, RFC1483LLC_LEN);
226 if (skb->protocol == htons(ETH_P_ARP)) {
227 skb->dev->stats.rx_packets++;
228 skb->dev->stats.rx_bytes += skb->len;
229 clip_arp_rcv(skb);
230 return;
231 }
232 }
233 clip_vcc->last_use = jiffies;
234 skb->dev->stats.rx_packets++;
235 skb->dev->stats.rx_bytes += skb->len;
236 memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
237 netif_rx(skb);
238 }
239
240 /*
241 * Note: these spinlocks _must_not_ block on non-SMP. The only goal is that
242 * clip_pop is atomic with respect to the critical section in clip_start_xmit.
243 */
244
clip_pop(struct atm_vcc * vcc,struct sk_buff * skb)245 static void clip_pop(struct atm_vcc *vcc, struct sk_buff *skb)
246 {
247 struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
248 struct net_device *dev = skb->dev;
249 int old;
250 unsigned long flags;
251
252 pr_debug("(vcc %p)\n", vcc);
253 clip_vcc->old_pop(vcc, skb);
254 /* skb->dev == NULL in outbound ARP packets */
255 if (!dev)
256 return;
257 spin_lock_irqsave(&PRIV(dev)->xoff_lock, flags);
258 if (atm_may_send(vcc, 0)) {
259 old = xchg(&clip_vcc->xoff, 0);
260 if (old)
261 netif_wake_queue(dev);
262 }
263 spin_unlock_irqrestore(&PRIV(dev)->xoff_lock, flags);
264 }
265
clip_neigh_solicit(struct neighbour * neigh,struct sk_buff * skb)266 static void clip_neigh_solicit(struct neighbour *neigh, struct sk_buff *skb)
267 {
268 __be32 *ip = (__be32 *) neigh->primary_key;
269
270 pr_debug("(neigh %p, skb %p)\n", neigh, skb);
271 to_atmarpd(act_need, PRIV(neigh->dev)->number, *ip);
272 }
273
clip_neigh_error(struct neighbour * neigh,struct sk_buff * skb)274 static void clip_neigh_error(struct neighbour *neigh, struct sk_buff *skb)
275 {
276 #ifndef CONFIG_ATM_CLIP_NO_ICMP
277 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
278 #endif
279 kfree_skb(skb);
280 }
281
282 static const struct neigh_ops clip_neigh_ops = {
283 .family = AF_INET,
284 .solicit = clip_neigh_solicit,
285 .error_report = clip_neigh_error,
286 .output = neigh_direct_output,
287 .connected_output = neigh_direct_output,
288 };
289
clip_constructor(struct net_device * dev,struct neighbour * neigh)290 static int clip_constructor(struct net_device *dev, struct neighbour *neigh)
291 {
292 struct atmarp_entry *entry = neighbour_priv(neigh);
293
294 if (neigh->tbl->family != AF_INET)
295 return -EINVAL;
296
297 if (neigh->type != RTN_UNICAST)
298 return -EINVAL;
299
300 neigh->nud_state = NUD_NONE;
301 neigh->ops = &clip_neigh_ops;
302 neigh->output = neigh->ops->output;
303 entry->neigh = neigh;
304 entry->vccs = NULL;
305 entry->expires = jiffies - 1;
306
307 return 0;
308 }
309
310 /* @@@ copy bh locking from arp.c -- need to bh-enable atm code before */
311
312 /*
313 * We play with the resolve flag: 0 and 1 have the usual meaning, but -1 means
314 * to allocate the neighbour entry but not to ask atmarpd for resolution. Also,
315 * don't increment the usage count. This is used to create entries in
316 * clip_setentry.
317 */
318
clip_encap(struct atm_vcc * vcc,int mode)319 static int clip_encap(struct atm_vcc *vcc, int mode)
320 {
321 if (!CLIP_VCC(vcc))
322 return -EBADFD;
323
324 CLIP_VCC(vcc)->encap = mode;
325 return 0;
326 }
327
clip_start_xmit(struct sk_buff * skb,struct net_device * dev)328 static netdev_tx_t clip_start_xmit(struct sk_buff *skb,
329 struct net_device *dev)
330 {
331 struct clip_priv *clip_priv = PRIV(dev);
332 struct dst_entry *dst = skb_dst(skb);
333 struct atmarp_entry *entry;
334 struct neighbour *n;
335 struct atm_vcc *vcc;
336 struct rtable *rt;
337 __be32 *daddr;
338 int old;
339 unsigned long flags;
340
341 pr_debug("(skb %p)\n", skb);
342 if (!dst) {
343 pr_err("skb_dst(skb) == NULL\n");
344 dev_kfree_skb(skb);
345 dev->stats.tx_dropped++;
346 return NETDEV_TX_OK;
347 }
348 rt = (struct rtable *) dst;
349 if (rt->rt_gw_family == AF_INET)
350 daddr = &rt->rt_gw4;
351 else
352 daddr = &ip_hdr(skb)->daddr;
353 n = dst_neigh_lookup(dst, daddr);
354 if (!n) {
355 pr_err("NO NEIGHBOUR !\n");
356 dev_kfree_skb(skb);
357 dev->stats.tx_dropped++;
358 return NETDEV_TX_OK;
359 }
360 entry = neighbour_priv(n);
361 if (!entry->vccs) {
362 if (time_after(jiffies, entry->expires)) {
363 /* should be resolved */
364 entry->expires = jiffies + ATMARP_RETRY_DELAY * HZ;
365 to_atmarpd(act_need, PRIV(dev)->number, *((__be32 *)n->primary_key));
366 }
367 if (entry->neigh->arp_queue.qlen < ATMARP_MAX_UNRES_PACKETS)
368 skb_queue_tail(&entry->neigh->arp_queue, skb);
369 else {
370 dev_kfree_skb(skb);
371 dev->stats.tx_dropped++;
372 }
373 goto out_release_neigh;
374 }
375 pr_debug("neigh %p, vccs %p\n", entry, entry->vccs);
376 ATM_SKB(skb)->vcc = vcc = entry->vccs->vcc;
377 pr_debug("using neighbour %p, vcc %p\n", n, vcc);
378 if (entry->vccs->encap) {
379 void *here;
380
381 here = skb_push(skb, RFC1483LLC_LEN);
382 memcpy(here, llc_oui, sizeof(llc_oui));
383 ((__be16 *) here)[3] = skb->protocol;
384 }
385 atm_account_tx(vcc, skb);
386 entry->vccs->last_use = jiffies;
387 pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, vcc, vcc->dev);
388 old = xchg(&entry->vccs->xoff, 1); /* assume XOFF ... */
389 if (old) {
390 pr_warn("XOFF->XOFF transition\n");
391 goto out_release_neigh;
392 }
393 dev->stats.tx_packets++;
394 dev->stats.tx_bytes += skb->len;
395 vcc->send(vcc, skb);
396 if (atm_may_send(vcc, 0)) {
397 entry->vccs->xoff = 0;
398 goto out_release_neigh;
399 }
400 spin_lock_irqsave(&clip_priv->xoff_lock, flags);
401 netif_stop_queue(dev); /* XOFF -> throttle immediately */
402 barrier();
403 if (!entry->vccs->xoff)
404 netif_start_queue(dev);
405 /* Oh, we just raced with clip_pop. netif_start_queue should be
406 good enough, because nothing should really be asleep because
407 of the brief netif_stop_queue. If this isn't true or if it
408 changes, use netif_wake_queue instead. */
409 spin_unlock_irqrestore(&clip_priv->xoff_lock, flags);
410 out_release_neigh:
411 neigh_release(n);
412 return NETDEV_TX_OK;
413 }
414
clip_mkip(struct atm_vcc * vcc,int timeout)415 static int clip_mkip(struct atm_vcc *vcc, int timeout)
416 {
417 struct clip_vcc *clip_vcc;
418
419 if (!vcc->push)
420 return -EBADFD;
421 clip_vcc = kmalloc(sizeof(struct clip_vcc), GFP_KERNEL);
422 if (!clip_vcc)
423 return -ENOMEM;
424 pr_debug("%p vcc %p\n", clip_vcc, vcc);
425 clip_vcc->vcc = vcc;
426 vcc->user_back = clip_vcc;
427 set_bit(ATM_VF_IS_CLIP, &vcc->flags);
428 clip_vcc->entry = NULL;
429 clip_vcc->xoff = 0;
430 clip_vcc->encap = 1;
431 clip_vcc->last_use = jiffies;
432 clip_vcc->idle_timeout = timeout * HZ;
433 clip_vcc->old_push = vcc->push;
434 clip_vcc->old_pop = vcc->pop;
435 vcc->push = clip_push;
436 vcc->pop = clip_pop;
437
438 /* re-process everything received between connection setup and MKIP */
439 vcc_process_recv_queue(vcc);
440
441 return 0;
442 }
443
clip_setentry(struct atm_vcc * vcc,__be32 ip)444 static int clip_setentry(struct atm_vcc *vcc, __be32 ip)
445 {
446 struct neighbour *neigh;
447 struct atmarp_entry *entry;
448 int error;
449 struct clip_vcc *clip_vcc;
450 struct rtable *rt;
451
452 if (vcc->push != clip_push) {
453 pr_warn("non-CLIP VCC\n");
454 return -EBADF;
455 }
456 clip_vcc = CLIP_VCC(vcc);
457 if (!ip) {
458 if (!clip_vcc->entry) {
459 pr_err("hiding hidden ATMARP entry\n");
460 return 0;
461 }
462 pr_debug("remove\n");
463 unlink_clip_vcc(clip_vcc);
464 return 0;
465 }
466 rt = ip_route_output(&init_net, ip, 0, 1, 0);
467 if (IS_ERR(rt))
468 return PTR_ERR(rt);
469 neigh = __neigh_lookup(&arp_tbl, &ip, rt->dst.dev, 1);
470 ip_rt_put(rt);
471 if (!neigh)
472 return -ENOMEM;
473 entry = neighbour_priv(neigh);
474 if (entry != clip_vcc->entry) {
475 if (!clip_vcc->entry)
476 pr_debug("add\n");
477 else {
478 pr_debug("update\n");
479 unlink_clip_vcc(clip_vcc);
480 }
481 link_vcc(clip_vcc, entry);
482 }
483 error = neigh_update(neigh, llc_oui, NUD_PERMANENT,
484 NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN, 0);
485 neigh_release(neigh);
486 return error;
487 }
488
489 static const struct net_device_ops clip_netdev_ops = {
490 .ndo_start_xmit = clip_start_xmit,
491 .ndo_neigh_construct = clip_constructor,
492 };
493
clip_setup(struct net_device * dev)494 static void clip_setup(struct net_device *dev)
495 {
496 dev->netdev_ops = &clip_netdev_ops;
497 dev->type = ARPHRD_ATM;
498 dev->neigh_priv_len = sizeof(struct atmarp_entry);
499 dev->hard_header_len = RFC1483LLC_LEN;
500 dev->mtu = RFC1626_MTU;
501 dev->tx_queue_len = 100; /* "normal" queue (packets) */
502 /* When using a "real" qdisc, the qdisc determines the queue */
503 /* length. tx_queue_len is only used for the default case, */
504 /* without any more elaborate queuing. 100 is a reasonable */
505 /* compromise between decent burst-tolerance and protection */
506 /* against memory hogs. */
507 netif_keep_dst(dev);
508 }
509
clip_create(int number)510 static int clip_create(int number)
511 {
512 struct net_device *dev;
513 struct clip_priv *clip_priv;
514 int error;
515
516 if (number != -1) {
517 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
518 if (PRIV(dev)->number == number)
519 return -EEXIST;
520 } else {
521 number = 0;
522 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
523 if (PRIV(dev)->number >= number)
524 number = PRIV(dev)->number + 1;
525 }
526 dev = alloc_netdev(sizeof(struct clip_priv), "", NET_NAME_UNKNOWN,
527 clip_setup);
528 if (!dev)
529 return -ENOMEM;
530 clip_priv = PRIV(dev);
531 sprintf(dev->name, "atm%d", number);
532 spin_lock_init(&clip_priv->xoff_lock);
533 clip_priv->number = number;
534 error = register_netdev(dev);
535 if (error) {
536 free_netdev(dev);
537 return error;
538 }
539 clip_priv->next = clip_devs;
540 clip_devs = dev;
541 pr_debug("registered (net:%s)\n", dev->name);
542 return number;
543 }
544
clip_device_event(struct notifier_block * this,unsigned long event,void * ptr)545 static int clip_device_event(struct notifier_block *this, unsigned long event,
546 void *ptr)
547 {
548 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
549
550 if (!net_eq(dev_net(dev), &init_net))
551 return NOTIFY_DONE;
552
553 if (event == NETDEV_UNREGISTER)
554 return NOTIFY_DONE;
555
556 /* ignore non-CLIP devices */
557 if (dev->type != ARPHRD_ATM || dev->netdev_ops != &clip_netdev_ops)
558 return NOTIFY_DONE;
559
560 switch (event) {
561 case NETDEV_UP:
562 pr_debug("NETDEV_UP\n");
563 to_atmarpd(act_up, PRIV(dev)->number, 0);
564 break;
565 case NETDEV_GOING_DOWN:
566 pr_debug("NETDEV_DOWN\n");
567 to_atmarpd(act_down, PRIV(dev)->number, 0);
568 break;
569 case NETDEV_CHANGE:
570 case NETDEV_CHANGEMTU:
571 pr_debug("NETDEV_CHANGE*\n");
572 to_atmarpd(act_change, PRIV(dev)->number, 0);
573 break;
574 }
575 return NOTIFY_DONE;
576 }
577
clip_inet_event(struct notifier_block * this,unsigned long event,void * ifa)578 static int clip_inet_event(struct notifier_block *this, unsigned long event,
579 void *ifa)
580 {
581 struct in_device *in_dev;
582 struct netdev_notifier_info info;
583
584 in_dev = ((struct in_ifaddr *)ifa)->ifa_dev;
585 /*
586 * Transitions are of the down-change-up type, so it's sufficient to
587 * handle the change on up.
588 */
589 if (event != NETDEV_UP)
590 return NOTIFY_DONE;
591 netdev_notifier_info_init(&info, in_dev->dev);
592 return clip_device_event(this, NETDEV_CHANGE, &info);
593 }
594
595 static struct notifier_block clip_dev_notifier = {
596 .notifier_call = clip_device_event,
597 };
598
599
600
601 static struct notifier_block clip_inet_notifier = {
602 .notifier_call = clip_inet_event,
603 };
604
605
606
atmarpd_close(struct atm_vcc * vcc)607 static void atmarpd_close(struct atm_vcc *vcc)
608 {
609 pr_debug("\n");
610
611 rtnl_lock();
612 atmarpd = NULL;
613 skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
614 rtnl_unlock();
615
616 pr_debug("(done)\n");
617 module_put(THIS_MODULE);
618 }
619
620 static const struct atmdev_ops atmarpd_dev_ops = {
621 .close = atmarpd_close
622 };
623
624
625 static struct atm_dev atmarpd_dev = {
626 .ops = &atmarpd_dev_ops,
627 .type = "arpd",
628 .number = 999,
629 .lock = __SPIN_LOCK_UNLOCKED(atmarpd_dev.lock)
630 };
631
632
atm_init_atmarp(struct atm_vcc * vcc)633 static int atm_init_atmarp(struct atm_vcc *vcc)
634 {
635 rtnl_lock();
636 if (atmarpd) {
637 rtnl_unlock();
638 return -EADDRINUSE;
639 }
640
641 mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ);
642
643 atmarpd = vcc;
644 set_bit(ATM_VF_META, &vcc->flags);
645 set_bit(ATM_VF_READY, &vcc->flags);
646 /* allow replies and avoid getting closed if signaling dies */
647 vcc->dev = &atmarpd_dev;
648 vcc_insert_socket(sk_atm(vcc));
649 vcc->push = NULL;
650 vcc->pop = NULL; /* crash */
651 vcc->push_oam = NULL; /* crash */
652 rtnl_unlock();
653 return 0;
654 }
655
clip_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)656 static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
657 {
658 struct atm_vcc *vcc = ATM_SD(sock);
659 int err = 0;
660
661 switch (cmd) {
662 case SIOCMKCLIP:
663 case ATMARPD_CTRL:
664 case ATMARP_MKIP:
665 case ATMARP_SETENTRY:
666 case ATMARP_ENCAP:
667 if (!capable(CAP_NET_ADMIN))
668 return -EPERM;
669 break;
670 default:
671 return -ENOIOCTLCMD;
672 }
673
674 switch (cmd) {
675 case SIOCMKCLIP:
676 err = clip_create(arg);
677 break;
678 case ATMARPD_CTRL:
679 err = atm_init_atmarp(vcc);
680 if (!err) {
681 sock->state = SS_CONNECTED;
682 __module_get(THIS_MODULE);
683 }
684 break;
685 case ATMARP_MKIP:
686 err = clip_mkip(vcc, arg);
687 break;
688 case ATMARP_SETENTRY:
689 err = clip_setentry(vcc, (__force __be32)arg);
690 break;
691 case ATMARP_ENCAP:
692 err = clip_encap(vcc, arg);
693 break;
694 }
695 return err;
696 }
697
698 static struct atm_ioctl clip_ioctl_ops = {
699 .owner = THIS_MODULE,
700 .ioctl = clip_ioctl,
701 };
702
703 #ifdef CONFIG_PROC_FS
704
svc_addr(struct seq_file * seq,struct sockaddr_atmsvc * addr)705 static void svc_addr(struct seq_file *seq, struct sockaddr_atmsvc *addr)
706 {
707 static int code[] = { 1, 2, 10, 6, 1, 0 };
708 static int e164[] = { 1, 8, 4, 6, 1, 0 };
709
710 if (*addr->sas_addr.pub) {
711 seq_printf(seq, "%s", addr->sas_addr.pub);
712 if (*addr->sas_addr.prv)
713 seq_putc(seq, '+');
714 } else if (!*addr->sas_addr.prv) {
715 seq_printf(seq, "%s", "(none)");
716 return;
717 }
718 if (*addr->sas_addr.prv) {
719 unsigned char *prv = addr->sas_addr.prv;
720 int *fields;
721 int i, j;
722
723 fields = *prv == ATM_AFI_E164 ? e164 : code;
724 for (i = 0; fields[i]; i++) {
725 for (j = fields[i]; j; j--)
726 seq_printf(seq, "%02X", *prv++);
727 if (fields[i + 1])
728 seq_putc(seq, '.');
729 }
730 }
731 }
732
733 /* This means the neighbour entry has no attached VCC objects. */
734 #define SEQ_NO_VCC_TOKEN ((void *) 2)
735
atmarp_info(struct seq_file * seq,struct neighbour * n,struct atmarp_entry * entry,struct clip_vcc * clip_vcc)736 static void atmarp_info(struct seq_file *seq, struct neighbour *n,
737 struct atmarp_entry *entry, struct clip_vcc *clip_vcc)
738 {
739 struct net_device *dev = n->dev;
740 unsigned long exp;
741 char buf[17];
742 int svc, llc, off;
743
744 svc = ((clip_vcc == SEQ_NO_VCC_TOKEN) ||
745 (sk_atm(clip_vcc->vcc)->sk_family == AF_ATMSVC));
746
747 llc = ((clip_vcc == SEQ_NO_VCC_TOKEN) || clip_vcc->encap);
748
749 if (clip_vcc == SEQ_NO_VCC_TOKEN)
750 exp = entry->neigh->used;
751 else
752 exp = clip_vcc->last_use;
753
754 exp = (jiffies - exp) / HZ;
755
756 seq_printf(seq, "%-6s%-4s%-4s%5ld ",
757 dev->name, svc ? "SVC" : "PVC", llc ? "LLC" : "NULL", exp);
758
759 off = scnprintf(buf, sizeof(buf) - 1, "%pI4", n->primary_key);
760 while (off < 16)
761 buf[off++] = ' ';
762 buf[off] = '\0';
763 seq_printf(seq, "%s", buf);
764
765 if (clip_vcc == SEQ_NO_VCC_TOKEN) {
766 if (time_before(jiffies, entry->expires))
767 seq_printf(seq, "(resolving)\n");
768 else
769 seq_printf(seq, "(expired, ref %d)\n",
770 refcount_read(&entry->neigh->refcnt));
771 } else if (!svc) {
772 seq_printf(seq, "%d.%d.%d\n",
773 clip_vcc->vcc->dev->number,
774 clip_vcc->vcc->vpi, clip_vcc->vcc->vci);
775 } else {
776 svc_addr(seq, &clip_vcc->vcc->remote);
777 seq_putc(seq, '\n');
778 }
779 }
780
781 struct clip_seq_state {
782 /* This member must be first. */
783 struct neigh_seq_state ns;
784
785 /* Local to clip specific iteration. */
786 struct clip_vcc *vcc;
787 };
788
clip_seq_next_vcc(struct atmarp_entry * e,struct clip_vcc * curr)789 static struct clip_vcc *clip_seq_next_vcc(struct atmarp_entry *e,
790 struct clip_vcc *curr)
791 {
792 if (!curr) {
793 curr = e->vccs;
794 if (!curr)
795 return SEQ_NO_VCC_TOKEN;
796 return curr;
797 }
798 if (curr == SEQ_NO_VCC_TOKEN)
799 return NULL;
800
801 curr = curr->next;
802
803 return curr;
804 }
805
clip_seq_vcc_walk(struct clip_seq_state * state,struct atmarp_entry * e,loff_t * pos)806 static void *clip_seq_vcc_walk(struct clip_seq_state *state,
807 struct atmarp_entry *e, loff_t * pos)
808 {
809 struct clip_vcc *vcc = state->vcc;
810
811 vcc = clip_seq_next_vcc(e, vcc);
812 if (vcc && pos != NULL) {
813 while (*pos) {
814 vcc = clip_seq_next_vcc(e, vcc);
815 if (!vcc)
816 break;
817 --(*pos);
818 }
819 }
820 state->vcc = vcc;
821
822 return vcc;
823 }
824
clip_seq_sub_iter(struct neigh_seq_state * _state,struct neighbour * n,loff_t * pos)825 static void *clip_seq_sub_iter(struct neigh_seq_state *_state,
826 struct neighbour *n, loff_t * pos)
827 {
828 struct clip_seq_state *state = (struct clip_seq_state *)_state;
829
830 if (n->dev->type != ARPHRD_ATM)
831 return NULL;
832
833 return clip_seq_vcc_walk(state, neighbour_priv(n), pos);
834 }
835
clip_seq_start(struct seq_file * seq,loff_t * pos)836 static void *clip_seq_start(struct seq_file *seq, loff_t * pos)
837 {
838 struct clip_seq_state *state = seq->private;
839 state->ns.neigh_sub_iter = clip_seq_sub_iter;
840 return neigh_seq_start(seq, pos, &arp_tbl, NEIGH_SEQ_NEIGH_ONLY);
841 }
842
clip_seq_show(struct seq_file * seq,void * v)843 static int clip_seq_show(struct seq_file *seq, void *v)
844 {
845 static char atm_arp_banner[] =
846 "IPitf TypeEncp Idle IP address ATM address\n";
847
848 if (v == SEQ_START_TOKEN) {
849 seq_puts(seq, atm_arp_banner);
850 } else {
851 struct clip_seq_state *state = seq->private;
852 struct clip_vcc *vcc = state->vcc;
853 struct neighbour *n = v;
854
855 atmarp_info(seq, n, neighbour_priv(n), vcc);
856 }
857 return 0;
858 }
859
860 static const struct seq_operations arp_seq_ops = {
861 .start = clip_seq_start,
862 .next = neigh_seq_next,
863 .stop = neigh_seq_stop,
864 .show = clip_seq_show,
865 };
866 #endif
867
868 static void atm_clip_exit_noproc(void);
869
atm_clip_init(void)870 static int __init atm_clip_init(void)
871 {
872 register_atm_ioctl(&clip_ioctl_ops);
873 register_netdevice_notifier(&clip_dev_notifier);
874 register_inetaddr_notifier(&clip_inet_notifier);
875
876 timer_setup(&idle_timer, idle_timer_check, 0);
877
878 #ifdef CONFIG_PROC_FS
879 {
880 struct proc_dir_entry *p;
881
882 p = proc_create_net("arp", 0444, atm_proc_root, &arp_seq_ops,
883 sizeof(struct clip_seq_state));
884 if (!p) {
885 pr_err("Unable to initialize /proc/net/atm/arp\n");
886 atm_clip_exit_noproc();
887 return -ENOMEM;
888 }
889 }
890 #endif
891
892 return 0;
893 }
894
atm_clip_exit_noproc(void)895 static void atm_clip_exit_noproc(void)
896 {
897 struct net_device *dev, *next;
898
899 unregister_inetaddr_notifier(&clip_inet_notifier);
900 unregister_netdevice_notifier(&clip_dev_notifier);
901
902 deregister_atm_ioctl(&clip_ioctl_ops);
903
904 /* First, stop the idle timer, so it stops banging
905 * on the table.
906 */
907 del_timer_sync(&idle_timer);
908
909 dev = clip_devs;
910 while (dev) {
911 next = PRIV(dev)->next;
912 unregister_netdev(dev);
913 free_netdev(dev);
914 dev = next;
915 }
916 }
917
atm_clip_exit(void)918 static void __exit atm_clip_exit(void)
919 {
920 remove_proc_entry("arp", atm_proc_root);
921
922 atm_clip_exit_noproc();
923 }
924
925 module_init(atm_clip_init);
926 module_exit(atm_clip_exit);
927 MODULE_AUTHOR("Werner Almesberger");
928 MODULE_DESCRIPTION("Classical/IP over ATM interface");
929 MODULE_LICENSE("GPL");
930