1 /* net/atm/clip.c - RFC1577 Classical IP over ATM */
2
3 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
4
5 #include <linux/string.h>
6 #include <linux/errno.h>
7 #include <linux/kernel.h> /* for UINT_MAX */
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/netdevice.h>
11 #include <linux/skbuff.h>
12 #include <linux/wait.h>
13 #include <linux/timer.h>
14 #include <linux/if_arp.h> /* for some manifest constants */
15 #include <linux/notifier.h>
16 #include <linux/atm.h>
17 #include <linux/atmdev.h>
18 #include <linux/atmclip.h>
19 #include <linux/atmarp.h>
20 #include <linux/capability.h>
21 #include <linux/ip.h> /* for net/route.h */
22 #include <linux/in.h> /* for struct sockaddr_in */
23 #include <linux/if.h> /* for IFF_UP */
24 #include <linux/inetdevice.h>
25 #include <linux/bitops.h>
26 #include <linux/poison.h>
27 #include <linux/proc_fs.h>
28 #include <linux/seq_file.h>
29 #include <linux/rcupdate.h>
30 #include <linux/jhash.h>
31 #include <net/route.h> /* for struct rtable and routing */
32 #include <net/icmp.h> /* icmp_send */
33 #include <asm/param.h> /* for HZ */
34 #include <asm/byteorder.h> /* for htons etc. */
35 #include <asm/system.h> /* save/restore_flags */
36 #include <asm/uaccess.h>
37 #include <asm/atomic.h>
38
39 #include "common.h"
40 #include "resources.h"
41 #include <net/atmclip.h>
42
43 static struct net_device *clip_devs;
44 static struct atm_vcc *atmarpd;
45 static struct neigh_table clip_tbl;
46 static struct timer_list idle_timer;
47
to_atmarpd(enum atmarp_ctrl_type type,int itf,__be32 ip)48 static int to_atmarpd(enum atmarp_ctrl_type type, int itf, __be32 ip)
49 {
50 struct sock *sk;
51 struct atmarp_ctrl *ctrl;
52 struct sk_buff *skb;
53
54 pr_debug("to_atmarpd(%d)\n", type);
55 if (!atmarpd)
56 return -EUNATCH;
57 skb = alloc_skb(sizeof(struct atmarp_ctrl),GFP_ATOMIC);
58 if (!skb)
59 return -ENOMEM;
60 ctrl = (struct atmarp_ctrl *) skb_put(skb,sizeof(struct atmarp_ctrl));
61 ctrl->type = type;
62 ctrl->itf_num = itf;
63 ctrl->ip = ip;
64 atm_force_charge(atmarpd, skb->truesize);
65
66 sk = sk_atm(atmarpd);
67 skb_queue_tail(&sk->sk_receive_queue, skb);
68 sk->sk_data_ready(sk, skb->len);
69 return 0;
70 }
71
link_vcc(struct clip_vcc * clip_vcc,struct atmarp_entry * entry)72 static void link_vcc(struct clip_vcc *clip_vcc, struct atmarp_entry *entry)
73 {
74 pr_debug("link_vcc %p to entry %p (neigh %p)\n", clip_vcc, entry,
75 entry->neigh);
76 clip_vcc->entry = entry;
77 clip_vcc->xoff = 0; /* @@@ may overrun buffer by one packet */
78 clip_vcc->next = entry->vccs;
79 entry->vccs = clip_vcc;
80 entry->neigh->used = jiffies;
81 }
82
unlink_clip_vcc(struct clip_vcc * clip_vcc)83 static void unlink_clip_vcc(struct clip_vcc *clip_vcc)
84 {
85 struct atmarp_entry *entry = clip_vcc->entry;
86 struct clip_vcc **walk;
87
88 if (!entry) {
89 printk(KERN_CRIT "!clip_vcc->entry (clip_vcc %p)\n", clip_vcc);
90 return;
91 }
92 netif_tx_lock_bh(entry->neigh->dev); /* block clip_start_xmit() */
93 entry->neigh->used = jiffies;
94 for (walk = &entry->vccs; *walk; walk = &(*walk)->next)
95 if (*walk == clip_vcc) {
96 int error;
97
98 *walk = clip_vcc->next; /* atomic */
99 clip_vcc->entry = NULL;
100 if (clip_vcc->xoff)
101 netif_wake_queue(entry->neigh->dev);
102 if (entry->vccs)
103 goto out;
104 entry->expires = jiffies - 1;
105 /* force resolution or expiration */
106 error = neigh_update(entry->neigh, NULL, NUD_NONE,
107 NEIGH_UPDATE_F_ADMIN);
108 if (error)
109 printk(KERN_CRIT "unlink_clip_vcc: "
110 "neigh_update failed with %d\n", error);
111 goto out;
112 }
113 printk(KERN_CRIT "ATMARP: unlink_clip_vcc failed (entry %p, vcc "
114 "0x%p)\n", entry, clip_vcc);
115 out:
116 netif_tx_unlock_bh(entry->neigh->dev);
117 }
118
119 /* The neighbour entry n->lock is held. */
neigh_check_cb(struct neighbour * n)120 static int neigh_check_cb(struct neighbour *n)
121 {
122 struct atmarp_entry *entry = NEIGH2ENTRY(n);
123 struct clip_vcc *cv;
124
125 for (cv = entry->vccs; cv; cv = cv->next) {
126 unsigned long exp = cv->last_use + cv->idle_timeout;
127
128 if (cv->idle_timeout && time_after(jiffies, exp)) {
129 pr_debug("releasing vcc %p->%p of entry %p\n",
130 cv, cv->vcc, entry);
131 vcc_release_async(cv->vcc, -ETIMEDOUT);
132 }
133 }
134
135 if (entry->vccs || time_before(jiffies, entry->expires))
136 return 0;
137
138 if (atomic_read(&n->refcnt) > 1) {
139 struct sk_buff *skb;
140
141 pr_debug("destruction postponed with ref %d\n",
142 atomic_read(&n->refcnt));
143
144 while ((skb = skb_dequeue(&n->arp_queue)) != NULL)
145 dev_kfree_skb(skb);
146
147 return 0;
148 }
149
150 pr_debug("expired neigh %p\n", n);
151 return 1;
152 }
153
idle_timer_check(unsigned long dummy)154 static void idle_timer_check(unsigned long dummy)
155 {
156 write_lock(&clip_tbl.lock);
157 __neigh_for_each_release(&clip_tbl, neigh_check_cb);
158 mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ);
159 write_unlock(&clip_tbl.lock);
160 }
161
clip_arp_rcv(struct sk_buff * skb)162 static int clip_arp_rcv(struct sk_buff *skb)
163 {
164 struct atm_vcc *vcc;
165
166 pr_debug("clip_arp_rcv\n");
167 vcc = ATM_SKB(skb)->vcc;
168 if (!vcc || !atm_charge(vcc, skb->truesize)) {
169 dev_kfree_skb_any(skb);
170 return 0;
171 }
172 pr_debug("pushing to %p\n", vcc);
173 pr_debug("using %p\n", CLIP_VCC(vcc)->old_push);
174 CLIP_VCC(vcc)->old_push(vcc, skb);
175 return 0;
176 }
177
178 static const unsigned char llc_oui[] = {
179 0xaa, /* DSAP: non-ISO */
180 0xaa, /* SSAP: non-ISO */
181 0x03, /* Ctrl: Unnumbered Information Command PDU */
182 0x00, /* OUI: EtherType */
183 0x00,
184 0x00
185 };
186
clip_push(struct atm_vcc * vcc,struct sk_buff * skb)187 static void clip_push(struct atm_vcc *vcc, struct sk_buff *skb)
188 {
189 struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
190
191 pr_debug("clip push\n");
192 if (!skb) {
193 pr_debug("removing VCC %p\n", clip_vcc);
194 if (clip_vcc->entry)
195 unlink_clip_vcc(clip_vcc);
196 clip_vcc->old_push(vcc, NULL); /* pass on the bad news */
197 kfree(clip_vcc);
198 return;
199 }
200 atm_return(vcc, skb->truesize);
201 skb->dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : clip_devs;
202 /* clip_vcc->entry == NULL if we don't have an IP address yet */
203 if (!skb->dev) {
204 dev_kfree_skb_any(skb);
205 return;
206 }
207 ATM_SKB(skb)->vcc = vcc;
208 skb_reset_mac_header(skb);
209 if (!clip_vcc->encap
210 || skb->len < RFC1483LLC_LEN
211 || memcmp(skb->data, llc_oui, sizeof (llc_oui)))
212 skb->protocol = htons(ETH_P_IP);
213 else {
214 skb->protocol = ((__be16 *) skb->data)[3];
215 skb_pull(skb, RFC1483LLC_LEN);
216 if (skb->protocol == htons(ETH_P_ARP)) {
217 PRIV(skb->dev)->stats.rx_packets++;
218 PRIV(skb->dev)->stats.rx_bytes += skb->len;
219 clip_arp_rcv(skb);
220 return;
221 }
222 }
223 clip_vcc->last_use = jiffies;
224 PRIV(skb->dev)->stats.rx_packets++;
225 PRIV(skb->dev)->stats.rx_bytes += skb->len;
226 memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
227 netif_rx(skb);
228 }
229
230 /*
231 * Note: these spinlocks _must_not_ block on non-SMP. The only goal is that
232 * clip_pop is atomic with respect to the critical section in clip_start_xmit.
233 */
234
clip_pop(struct atm_vcc * vcc,struct sk_buff * skb)235 static void clip_pop(struct atm_vcc *vcc, struct sk_buff *skb)
236 {
237 struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
238 struct net_device *dev = skb->dev;
239 int old;
240 unsigned long flags;
241
242 pr_debug("clip_pop(vcc %p)\n", vcc);
243 clip_vcc->old_pop(vcc, skb);
244 /* skb->dev == NULL in outbound ARP packets */
245 if (!dev)
246 return;
247 spin_lock_irqsave(&PRIV(dev)->xoff_lock, flags);
248 if (atm_may_send(vcc, 0)) {
249 old = xchg(&clip_vcc->xoff, 0);
250 if (old)
251 netif_wake_queue(dev);
252 }
253 spin_unlock_irqrestore(&PRIV(dev)->xoff_lock, flags);
254 }
255
clip_neigh_solicit(struct neighbour * neigh,struct sk_buff * skb)256 static void clip_neigh_solicit(struct neighbour *neigh, struct sk_buff *skb)
257 {
258 pr_debug("clip_neigh_solicit (neigh %p, skb %p)\n", neigh, skb);
259 to_atmarpd(act_need, PRIV(neigh->dev)->number, NEIGH2ENTRY(neigh)->ip);
260 }
261
clip_neigh_error(struct neighbour * neigh,struct sk_buff * skb)262 static void clip_neigh_error(struct neighbour *neigh, struct sk_buff *skb)
263 {
264 #ifndef CONFIG_ATM_CLIP_NO_ICMP
265 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
266 #endif
267 kfree_skb(skb);
268 }
269
270 static struct neigh_ops clip_neigh_ops = {
271 .family = AF_INET,
272 .solicit = clip_neigh_solicit,
273 .error_report = clip_neigh_error,
274 .output = dev_queue_xmit,
275 .connected_output = dev_queue_xmit,
276 .hh_output = dev_queue_xmit,
277 .queue_xmit = dev_queue_xmit,
278 };
279
clip_constructor(struct neighbour * neigh)280 static int clip_constructor(struct neighbour *neigh)
281 {
282 struct atmarp_entry *entry = NEIGH2ENTRY(neigh);
283 struct net_device *dev = neigh->dev;
284 struct in_device *in_dev;
285 struct neigh_parms *parms;
286
287 pr_debug("clip_constructor (neigh %p, entry %p)\n", neigh, entry);
288 neigh->type = inet_addr_type(&init_net, entry->ip);
289 if (neigh->type != RTN_UNICAST)
290 return -EINVAL;
291
292 rcu_read_lock();
293 in_dev = __in_dev_get_rcu(dev);
294 if (!in_dev) {
295 rcu_read_unlock();
296 return -EINVAL;
297 }
298
299 parms = in_dev->arp_parms;
300 __neigh_parms_put(neigh->parms);
301 neigh->parms = neigh_parms_clone(parms);
302 rcu_read_unlock();
303
304 neigh->ops = &clip_neigh_ops;
305 neigh->output = neigh->nud_state & NUD_VALID ?
306 neigh->ops->connected_output : neigh->ops->output;
307 entry->neigh = neigh;
308 entry->vccs = NULL;
309 entry->expires = jiffies - 1;
310 return 0;
311 }
312
clip_hash(const void * pkey,const struct net_device * dev)313 static u32 clip_hash(const void *pkey, const struct net_device *dev)
314 {
315 return jhash_2words(*(u32 *) pkey, dev->ifindex, clip_tbl.hash_rnd);
316 }
317
318 static struct neigh_table clip_tbl = {
319 .family = AF_INET,
320 .entry_size = sizeof(struct neighbour)+sizeof(struct atmarp_entry),
321 .key_len = 4,
322 .hash = clip_hash,
323 .constructor = clip_constructor,
324 .id = "clip_arp_cache",
325
326 /* parameters are copied from ARP ... */
327 .parms = {
328 .tbl = &clip_tbl,
329 .base_reachable_time = 30 * HZ,
330 .retrans_time = 1 * HZ,
331 .gc_staletime = 60 * HZ,
332 .reachable_time = 30 * HZ,
333 .delay_probe_time = 5 * HZ,
334 .queue_len = 3,
335 .ucast_probes = 3,
336 .mcast_probes = 3,
337 .anycast_delay = 1 * HZ,
338 .proxy_delay = (8 * HZ) / 10,
339 .proxy_qlen = 64,
340 .locktime = 1 * HZ,
341 },
342 .gc_interval = 30 * HZ,
343 .gc_thresh1 = 128,
344 .gc_thresh2 = 512,
345 .gc_thresh3 = 1024,
346 };
347
348 /* @@@ copy bh locking from arp.c -- need to bh-enable atm code before */
349
350 /*
351 * We play with the resolve flag: 0 and 1 have the usual meaning, but -1 means
352 * to allocate the neighbour entry but not to ask atmarpd for resolution. Also,
353 * don't increment the usage count. This is used to create entries in
354 * clip_setentry.
355 */
356
clip_encap(struct atm_vcc * vcc,int mode)357 static int clip_encap(struct atm_vcc *vcc, int mode)
358 {
359 CLIP_VCC(vcc)->encap = mode;
360 return 0;
361 }
362
clip_start_xmit(struct sk_buff * skb,struct net_device * dev)363 static int clip_start_xmit(struct sk_buff *skb, struct net_device *dev)
364 {
365 struct clip_priv *clip_priv = PRIV(dev);
366 struct atmarp_entry *entry;
367 struct atm_vcc *vcc;
368 int old;
369 unsigned long flags;
370
371 pr_debug("clip_start_xmit (skb %p)\n", skb);
372 if (!skb->dst) {
373 printk(KERN_ERR "clip_start_xmit: skb->dst == NULL\n");
374 dev_kfree_skb(skb);
375 clip_priv->stats.tx_dropped++;
376 return 0;
377 }
378 if (!skb->dst->neighbour) {
379 #if 0
380 skb->dst->neighbour = clip_find_neighbour(skb->dst, 1);
381 if (!skb->dst->neighbour) {
382 dev_kfree_skb(skb); /* lost that one */
383 clip_priv->stats.tx_dropped++;
384 return 0;
385 }
386 #endif
387 printk(KERN_ERR "clip_start_xmit: NO NEIGHBOUR !\n");
388 dev_kfree_skb(skb);
389 clip_priv->stats.tx_dropped++;
390 return 0;
391 }
392 entry = NEIGH2ENTRY(skb->dst->neighbour);
393 if (!entry->vccs) {
394 if (time_after(jiffies, entry->expires)) {
395 /* should be resolved */
396 entry->expires = jiffies + ATMARP_RETRY_DELAY * HZ;
397 to_atmarpd(act_need, PRIV(dev)->number, entry->ip);
398 }
399 if (entry->neigh->arp_queue.qlen < ATMARP_MAX_UNRES_PACKETS)
400 skb_queue_tail(&entry->neigh->arp_queue, skb);
401 else {
402 dev_kfree_skb(skb);
403 clip_priv->stats.tx_dropped++;
404 }
405 return 0;
406 }
407 pr_debug("neigh %p, vccs %p\n", entry, entry->vccs);
408 ATM_SKB(skb)->vcc = vcc = entry->vccs->vcc;
409 pr_debug("using neighbour %p, vcc %p\n", skb->dst->neighbour, vcc);
410 if (entry->vccs->encap) {
411 void *here;
412
413 here = skb_push(skb, RFC1483LLC_LEN);
414 memcpy(here, llc_oui, sizeof(llc_oui));
415 ((__be16 *) here)[3] = skb->protocol;
416 }
417 atomic_add(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);
418 ATM_SKB(skb)->atm_options = vcc->atm_options;
419 entry->vccs->last_use = jiffies;
420 pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, vcc, vcc->dev);
421 old = xchg(&entry->vccs->xoff, 1); /* assume XOFF ... */
422 if (old) {
423 printk(KERN_WARNING "clip_start_xmit: XOFF->XOFF transition\n");
424 return 0;
425 }
426 clip_priv->stats.tx_packets++;
427 clip_priv->stats.tx_bytes += skb->len;
428 vcc->send(vcc, skb);
429 if (atm_may_send(vcc, 0)) {
430 entry->vccs->xoff = 0;
431 return 0;
432 }
433 spin_lock_irqsave(&clip_priv->xoff_lock, flags);
434 netif_stop_queue(dev); /* XOFF -> throttle immediately */
435 barrier();
436 if (!entry->vccs->xoff)
437 netif_start_queue(dev);
438 /* Oh, we just raced with clip_pop. netif_start_queue should be
439 good enough, because nothing should really be asleep because
440 of the brief netif_stop_queue. If this isn't true or if it
441 changes, use netif_wake_queue instead. */
442 spin_unlock_irqrestore(&clip_priv->xoff_lock, flags);
443 return 0;
444 }
445
clip_get_stats(struct net_device * dev)446 static struct net_device_stats *clip_get_stats(struct net_device *dev)
447 {
448 return &PRIV(dev)->stats;
449 }
450
clip_mkip(struct atm_vcc * vcc,int timeout)451 static int clip_mkip(struct atm_vcc *vcc, int timeout)
452 {
453 struct clip_vcc *clip_vcc;
454 struct sk_buff *skb;
455 struct sk_buff_head *rq;
456 unsigned long flags;
457
458 if (!vcc->push)
459 return -EBADFD;
460 clip_vcc = kmalloc(sizeof(struct clip_vcc), GFP_KERNEL);
461 if (!clip_vcc)
462 return -ENOMEM;
463 pr_debug("mkip clip_vcc %p vcc %p\n", clip_vcc, vcc);
464 clip_vcc->vcc = vcc;
465 vcc->user_back = clip_vcc;
466 set_bit(ATM_VF_IS_CLIP, &vcc->flags);
467 clip_vcc->entry = NULL;
468 clip_vcc->xoff = 0;
469 clip_vcc->encap = 1;
470 clip_vcc->last_use = jiffies;
471 clip_vcc->idle_timeout = timeout * HZ;
472 clip_vcc->old_push = vcc->push;
473 clip_vcc->old_pop = vcc->pop;
474 vcc->push = clip_push;
475 vcc->pop = clip_pop;
476
477 rq = &sk_atm(vcc)->sk_receive_queue;
478
479 spin_lock_irqsave(&rq->lock, flags);
480 if (skb_queue_empty(rq)) {
481 skb = NULL;
482 } else {
483 /* NULL terminate the list. */
484 rq->prev->next = NULL;
485 skb = rq->next;
486 }
487 rq->prev = rq->next = (struct sk_buff *)rq;
488 rq->qlen = 0;
489 spin_unlock_irqrestore(&rq->lock, flags);
490
491 /* re-process everything received between connection setup and MKIP */
492 while (skb) {
493 struct sk_buff *next = skb->next;
494
495 skb->next = skb->prev = NULL;
496 if (!clip_devs) {
497 atm_return(vcc, skb->truesize);
498 kfree_skb(skb);
499 } else {
500 unsigned int len = skb->len;
501
502 skb_get(skb);
503 clip_push(vcc, skb);
504 PRIV(skb->dev)->stats.rx_packets--;
505 PRIV(skb->dev)->stats.rx_bytes -= len;
506 kfree_skb(skb);
507 }
508
509 skb = next;
510 }
511 return 0;
512 }
513
clip_setentry(struct atm_vcc * vcc,__be32 ip)514 static int clip_setentry(struct atm_vcc *vcc, __be32 ip)
515 {
516 struct neighbour *neigh;
517 struct atmarp_entry *entry;
518 int error;
519 struct clip_vcc *clip_vcc;
520 struct flowi fl = { .nl_u = { .ip4_u = { .daddr = ip, .tos = 1}} };
521 struct rtable *rt;
522
523 if (vcc->push != clip_push) {
524 printk(KERN_WARNING "clip_setentry: non-CLIP VCC\n");
525 return -EBADF;
526 }
527 clip_vcc = CLIP_VCC(vcc);
528 if (!ip) {
529 if (!clip_vcc->entry) {
530 printk(KERN_ERR "hiding hidden ATMARP entry\n");
531 return 0;
532 }
533 pr_debug("setentry: remove\n");
534 unlink_clip_vcc(clip_vcc);
535 return 0;
536 }
537 error = ip_route_output_key(&init_net, &rt, &fl);
538 if (error)
539 return error;
540 neigh = __neigh_lookup(&clip_tbl, &ip, rt->u.dst.dev, 1);
541 ip_rt_put(rt);
542 if (!neigh)
543 return -ENOMEM;
544 entry = NEIGH2ENTRY(neigh);
545 if (entry != clip_vcc->entry) {
546 if (!clip_vcc->entry)
547 pr_debug("setentry: add\n");
548 else {
549 pr_debug("setentry: update\n");
550 unlink_clip_vcc(clip_vcc);
551 }
552 link_vcc(clip_vcc, entry);
553 }
554 error = neigh_update(neigh, llc_oui, NUD_PERMANENT,
555 NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN);
556 neigh_release(neigh);
557 return error;
558 }
559
clip_setup(struct net_device * dev)560 static void clip_setup(struct net_device *dev)
561 {
562 dev->hard_start_xmit = clip_start_xmit;
563 /* sg_xmit ... */
564 dev->get_stats = clip_get_stats;
565 dev->type = ARPHRD_ATM;
566 dev->hard_header_len = RFC1483LLC_LEN;
567 dev->mtu = RFC1626_MTU;
568 dev->tx_queue_len = 100; /* "normal" queue (packets) */
569 /* When using a "real" qdisc, the qdisc determines the queue */
570 /* length. tx_queue_len is only used for the default case, */
571 /* without any more elaborate queuing. 100 is a reasonable */
572 /* compromise between decent burst-tolerance and protection */
573 /* against memory hogs. */
574 }
575
clip_create(int number)576 static int clip_create(int number)
577 {
578 struct net_device *dev;
579 struct clip_priv *clip_priv;
580 int error;
581
582 if (number != -1) {
583 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
584 if (PRIV(dev)->number == number)
585 return -EEXIST;
586 } else {
587 number = 0;
588 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
589 if (PRIV(dev)->number >= number)
590 number = PRIV(dev)->number + 1;
591 }
592 dev = alloc_netdev(sizeof(struct clip_priv), "", clip_setup);
593 if (!dev)
594 return -ENOMEM;
595 clip_priv = PRIV(dev);
596 sprintf(dev->name, "atm%d", number);
597 spin_lock_init(&clip_priv->xoff_lock);
598 clip_priv->number = number;
599 error = register_netdev(dev);
600 if (error) {
601 free_netdev(dev);
602 return error;
603 }
604 clip_priv->next = clip_devs;
605 clip_devs = dev;
606 pr_debug("registered (net:%s)\n", dev->name);
607 return number;
608 }
609
clip_device_event(struct notifier_block * this,unsigned long event,void * arg)610 static int clip_device_event(struct notifier_block *this, unsigned long event,
611 void *arg)
612 {
613 struct net_device *dev = arg;
614
615 if (!net_eq(dev_net(dev), &init_net))
616 return NOTIFY_DONE;
617
618 if (event == NETDEV_UNREGISTER) {
619 neigh_ifdown(&clip_tbl, dev);
620 return NOTIFY_DONE;
621 }
622
623 /* ignore non-CLIP devices */
624 if (dev->type != ARPHRD_ATM || dev->hard_start_xmit != clip_start_xmit)
625 return NOTIFY_DONE;
626
627 switch (event) {
628 case NETDEV_UP:
629 pr_debug("clip_device_event NETDEV_UP\n");
630 to_atmarpd(act_up, PRIV(dev)->number, 0);
631 break;
632 case NETDEV_GOING_DOWN:
633 pr_debug("clip_device_event NETDEV_DOWN\n");
634 to_atmarpd(act_down, PRIV(dev)->number, 0);
635 break;
636 case NETDEV_CHANGE:
637 case NETDEV_CHANGEMTU:
638 pr_debug("clip_device_event NETDEV_CHANGE*\n");
639 to_atmarpd(act_change, PRIV(dev)->number, 0);
640 break;
641 }
642 return NOTIFY_DONE;
643 }
644
clip_inet_event(struct notifier_block * this,unsigned long event,void * ifa)645 static int clip_inet_event(struct notifier_block *this, unsigned long event,
646 void *ifa)
647 {
648 struct in_device *in_dev;
649
650 in_dev = ((struct in_ifaddr *)ifa)->ifa_dev;
651 /*
652 * Transitions are of the down-change-up type, so it's sufficient to
653 * handle the change on up.
654 */
655 if (event != NETDEV_UP)
656 return NOTIFY_DONE;
657 return clip_device_event(this, NETDEV_CHANGE, in_dev->dev);
658 }
659
660
661 static struct notifier_block clip_dev_notifier = {
662 .notifier_call = clip_device_event,
663 };
664
665
666
667 static struct notifier_block clip_inet_notifier = {
668 .notifier_call = clip_inet_event,
669 };
670
671
672
atmarpd_close(struct atm_vcc * vcc)673 static void atmarpd_close(struct atm_vcc *vcc)
674 {
675 pr_debug("atmarpd_close\n");
676
677 rtnl_lock();
678 atmarpd = NULL;
679 skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
680 rtnl_unlock();
681
682 pr_debug("(done)\n");
683 module_put(THIS_MODULE);
684 }
685
686
687 static struct atmdev_ops atmarpd_dev_ops = {
688 .close = atmarpd_close
689 };
690
691
692 static struct atm_dev atmarpd_dev = {
693 .ops = &atmarpd_dev_ops,
694 .type = "arpd",
695 .number = 999,
696 .lock = __SPIN_LOCK_UNLOCKED(atmarpd_dev.lock)
697 };
698
699
atm_init_atmarp(struct atm_vcc * vcc)700 static int atm_init_atmarp(struct atm_vcc *vcc)
701 {
702 rtnl_lock();
703 if (atmarpd) {
704 rtnl_unlock();
705 return -EADDRINUSE;
706 }
707
708 mod_timer(&idle_timer, jiffies+CLIP_CHECK_INTERVAL*HZ);
709
710 atmarpd = vcc;
711 set_bit(ATM_VF_META,&vcc->flags);
712 set_bit(ATM_VF_READY,&vcc->flags);
713 /* allow replies and avoid getting closed if signaling dies */
714 vcc->dev = &atmarpd_dev;
715 vcc_insert_socket(sk_atm(vcc));
716 vcc->push = NULL;
717 vcc->pop = NULL; /* crash */
718 vcc->push_oam = NULL; /* crash */
719 rtnl_unlock();
720 return 0;
721 }
722
clip_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)723 static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
724 {
725 struct atm_vcc *vcc = ATM_SD(sock);
726 int err = 0;
727
728 switch (cmd) {
729 case SIOCMKCLIP:
730 case ATMARPD_CTRL:
731 case ATMARP_MKIP:
732 case ATMARP_SETENTRY:
733 case ATMARP_ENCAP:
734 if (!capable(CAP_NET_ADMIN))
735 return -EPERM;
736 break;
737 default:
738 return -ENOIOCTLCMD;
739 }
740
741 switch (cmd) {
742 case SIOCMKCLIP:
743 err = clip_create(arg);
744 break;
745 case ATMARPD_CTRL:
746 err = atm_init_atmarp(vcc);
747 if (!err) {
748 sock->state = SS_CONNECTED;
749 __module_get(THIS_MODULE);
750 }
751 break;
752 case ATMARP_MKIP:
753 err = clip_mkip(vcc, arg);
754 break;
755 case ATMARP_SETENTRY:
756 err = clip_setentry(vcc, (__force __be32)arg);
757 break;
758 case ATMARP_ENCAP:
759 err = clip_encap(vcc, arg);
760 break;
761 }
762 return err;
763 }
764
765 static struct atm_ioctl clip_ioctl_ops = {
766 .owner = THIS_MODULE,
767 .ioctl = clip_ioctl,
768 };
769
770 #ifdef CONFIG_PROC_FS
771
svc_addr(struct seq_file * seq,struct sockaddr_atmsvc * addr)772 static void svc_addr(struct seq_file *seq, struct sockaddr_atmsvc *addr)
773 {
774 static int code[] = { 1, 2, 10, 6, 1, 0 };
775 static int e164[] = { 1, 8, 4, 6, 1, 0 };
776
777 if (*addr->sas_addr.pub) {
778 seq_printf(seq, "%s", addr->sas_addr.pub);
779 if (*addr->sas_addr.prv)
780 seq_putc(seq, '+');
781 } else if (!*addr->sas_addr.prv) {
782 seq_printf(seq, "%s", "(none)");
783 return;
784 }
785 if (*addr->sas_addr.prv) {
786 unsigned char *prv = addr->sas_addr.prv;
787 int *fields;
788 int i, j;
789
790 fields = *prv == ATM_AFI_E164 ? e164 : code;
791 for (i = 0; fields[i]; i++) {
792 for (j = fields[i]; j; j--)
793 seq_printf(seq, "%02X", *prv++);
794 if (fields[i + 1])
795 seq_putc(seq, '.');
796 }
797 }
798 }
799
800 /* This means the neighbour entry has no attached VCC objects. */
801 #define SEQ_NO_VCC_TOKEN ((void *) 2)
802
atmarp_info(struct seq_file * seq,struct net_device * dev,struct atmarp_entry * entry,struct clip_vcc * clip_vcc)803 static void atmarp_info(struct seq_file *seq, struct net_device *dev,
804 struct atmarp_entry *entry, struct clip_vcc *clip_vcc)
805 {
806 unsigned long exp;
807 char buf[17];
808 int svc, llc, off;
809
810 svc = ((clip_vcc == SEQ_NO_VCC_TOKEN) ||
811 (sk_atm(clip_vcc->vcc)->sk_family == AF_ATMSVC));
812
813 llc = ((clip_vcc == SEQ_NO_VCC_TOKEN) || clip_vcc->encap);
814
815 if (clip_vcc == SEQ_NO_VCC_TOKEN)
816 exp = entry->neigh->used;
817 else
818 exp = clip_vcc->last_use;
819
820 exp = (jiffies - exp) / HZ;
821
822 seq_printf(seq, "%-6s%-4s%-4s%5ld ",
823 dev->name, svc ? "SVC" : "PVC", llc ? "LLC" : "NULL", exp);
824
825 off = scnprintf(buf, sizeof(buf) - 1, "%pI4",
826 &entry->ip);
827 while (off < 16)
828 buf[off++] = ' ';
829 buf[off] = '\0';
830 seq_printf(seq, "%s", buf);
831
832 if (clip_vcc == SEQ_NO_VCC_TOKEN) {
833 if (time_before(jiffies, entry->expires))
834 seq_printf(seq, "(resolving)\n");
835 else
836 seq_printf(seq, "(expired, ref %d)\n",
837 atomic_read(&entry->neigh->refcnt));
838 } else if (!svc) {
839 seq_printf(seq, "%d.%d.%d\n",
840 clip_vcc->vcc->dev->number,
841 clip_vcc->vcc->vpi, clip_vcc->vcc->vci);
842 } else {
843 svc_addr(seq, &clip_vcc->vcc->remote);
844 seq_putc(seq, '\n');
845 }
846 }
847
848 struct clip_seq_state {
849 /* This member must be first. */
850 struct neigh_seq_state ns;
851
852 /* Local to clip specific iteration. */
853 struct clip_vcc *vcc;
854 };
855
clip_seq_next_vcc(struct atmarp_entry * e,struct clip_vcc * curr)856 static struct clip_vcc *clip_seq_next_vcc(struct atmarp_entry *e,
857 struct clip_vcc *curr)
858 {
859 if (!curr) {
860 curr = e->vccs;
861 if (!curr)
862 return SEQ_NO_VCC_TOKEN;
863 return curr;
864 }
865 if (curr == SEQ_NO_VCC_TOKEN)
866 return NULL;
867
868 curr = curr->next;
869
870 return curr;
871 }
872
clip_seq_vcc_walk(struct clip_seq_state * state,struct atmarp_entry * e,loff_t * pos)873 static void *clip_seq_vcc_walk(struct clip_seq_state *state,
874 struct atmarp_entry *e, loff_t * pos)
875 {
876 struct clip_vcc *vcc = state->vcc;
877
878 vcc = clip_seq_next_vcc(e, vcc);
879 if (vcc && pos != NULL) {
880 while (*pos) {
881 vcc = clip_seq_next_vcc(e, vcc);
882 if (!vcc)
883 break;
884 --(*pos);
885 }
886 }
887 state->vcc = vcc;
888
889 return vcc;
890 }
891
clip_seq_sub_iter(struct neigh_seq_state * _state,struct neighbour * n,loff_t * pos)892 static void *clip_seq_sub_iter(struct neigh_seq_state *_state,
893 struct neighbour *n, loff_t * pos)
894 {
895 struct clip_seq_state *state = (struct clip_seq_state *)_state;
896
897 return clip_seq_vcc_walk(state, NEIGH2ENTRY(n), pos);
898 }
899
clip_seq_start(struct seq_file * seq,loff_t * pos)900 static void *clip_seq_start(struct seq_file *seq, loff_t * pos)
901 {
902 struct clip_seq_state *state = seq->private;
903 state->ns.neigh_sub_iter = clip_seq_sub_iter;
904 return neigh_seq_start(seq, pos, &clip_tbl, NEIGH_SEQ_NEIGH_ONLY);
905 }
906
clip_seq_show(struct seq_file * seq,void * v)907 static int clip_seq_show(struct seq_file *seq, void *v)
908 {
909 static char atm_arp_banner[] =
910 "IPitf TypeEncp Idle IP address ATM address\n";
911
912 if (v == SEQ_START_TOKEN) {
913 seq_puts(seq, atm_arp_banner);
914 } else {
915 struct clip_seq_state *state = seq->private;
916 struct neighbour *n = v;
917 struct clip_vcc *vcc = state->vcc;
918
919 atmarp_info(seq, n->dev, NEIGH2ENTRY(n), vcc);
920 }
921 return 0;
922 }
923
924 static const struct seq_operations arp_seq_ops = {
925 .start = clip_seq_start,
926 .next = neigh_seq_next,
927 .stop = neigh_seq_stop,
928 .show = clip_seq_show,
929 };
930
arp_seq_open(struct inode * inode,struct file * file)931 static int arp_seq_open(struct inode *inode, struct file *file)
932 {
933 return seq_open_net(inode, file, &arp_seq_ops,
934 sizeof(struct clip_seq_state));
935 }
936
937 static const struct file_operations arp_seq_fops = {
938 .open = arp_seq_open,
939 .read = seq_read,
940 .llseek = seq_lseek,
941 .release = seq_release_net,
942 .owner = THIS_MODULE
943 };
944 #endif
945
946 static void atm_clip_exit_noproc(void);
947
atm_clip_init(void)948 static int __init atm_clip_init(void)
949 {
950 neigh_table_init_no_netlink(&clip_tbl);
951
952 clip_tbl_hook = &clip_tbl;
953 register_atm_ioctl(&clip_ioctl_ops);
954 register_netdevice_notifier(&clip_dev_notifier);
955 register_inetaddr_notifier(&clip_inet_notifier);
956
957 setup_timer(&idle_timer, idle_timer_check, 0);
958
959 #ifdef CONFIG_PROC_FS
960 {
961 struct proc_dir_entry *p;
962
963 p = proc_create("arp", S_IRUGO, atm_proc_root, &arp_seq_fops);
964 if (!p) {
965 printk(KERN_ERR "Unable to initialize "
966 "/proc/net/atm/arp\n");
967 atm_clip_exit_noproc();
968 return -ENOMEM;
969 }
970 }
971 #endif
972
973 return 0;
974 }
975
atm_clip_exit_noproc(void)976 static void atm_clip_exit_noproc(void)
977 {
978 struct net_device *dev, *next;
979
980 unregister_inetaddr_notifier(&clip_inet_notifier);
981 unregister_netdevice_notifier(&clip_dev_notifier);
982
983 deregister_atm_ioctl(&clip_ioctl_ops);
984
985 /* First, stop the idle timer, so it stops banging
986 * on the table.
987 */
988 del_timer_sync(&idle_timer);
989
990 /* Next, purge the table, so that the device
991 * unregister loop below does not hang due to
992 * device references remaining in the table.
993 */
994 neigh_ifdown(&clip_tbl, NULL);
995
996 dev = clip_devs;
997 while (dev) {
998 next = PRIV(dev)->next;
999 unregister_netdev(dev);
1000 free_netdev(dev);
1001 dev = next;
1002 }
1003
1004 /* Now it is safe to fully shutdown whole table. */
1005 neigh_table_clear(&clip_tbl);
1006
1007 clip_tbl_hook = NULL;
1008 }
1009
atm_clip_exit(void)1010 static void __exit atm_clip_exit(void)
1011 {
1012 remove_proc_entry("arp", atm_proc_root);
1013
1014 atm_clip_exit_noproc();
1015 }
1016
1017 module_init(atm_clip_init);
1018 module_exit(atm_clip_exit);
1019 MODULE_AUTHOR("Werner Almesberger");
1020 MODULE_DESCRIPTION("Classical/IP over ATM interface");
1021 MODULE_LICENSE("GPL");
1022