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1/* net/atm/clip.c - RFC1577 Classical IP over ATM */
2
3/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
4
5#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
6
7#include <linux/string.h>
8#include <linux/errno.h>
9#include <linux/kernel.h> /* for UINT_MAX */
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/netdevice.h>
13#include <linux/skbuff.h>
14#include <linux/wait.h>
15#include <linux/timer.h>
16#include <linux/if_arp.h> /* for some manifest constants */
17#include <linux/notifier.h>
18#include <linux/atm.h>
19#include <linux/atmdev.h>
20#include <linux/atmclip.h>
21#include <linux/atmarp.h>
22#include <linux/capability.h>
23#include <linux/ip.h> /* for net/route.h */
24#include <linux/in.h> /* for struct sockaddr_in */
25#include <linux/if.h> /* for IFF_UP */
26#include <linux/inetdevice.h>
27#include <linux/bitops.h>
28#include <linux/poison.h>
29#include <linux/proc_fs.h>
30#include <linux/seq_file.h>
31#include <linux/rcupdate.h>
32#include <linux/jhash.h>
33#include <linux/slab.h>
34#include <net/route.h> /* for struct rtable and routing */
35#include <net/icmp.h> /* icmp_send */
36#include <linux/param.h> /* for HZ */
37#include <linux/uaccess.h>
38#include <asm/byteorder.h> /* for htons etc. */
39#include <asm/system.h> /* save/restore_flags */
40#include <linux/atomic.h>
41
42#include "common.h"
43#include "resources.h"
44#include <net/atmclip.h>
45
46static struct net_device *clip_devs;
47static struct atm_vcc *atmarpd;
48static struct neigh_table clip_tbl;
49static struct timer_list idle_timer;
50
51static int to_atmarpd(enum atmarp_ctrl_type type, int itf, __be32 ip)
52{
53 struct sock *sk;
54 struct atmarp_ctrl *ctrl;
55 struct sk_buff *skb;
56
57 pr_debug("(%d)\n", type);
58 if (!atmarpd)
59 return -EUNATCH;
60 skb = alloc_skb(sizeof(struct atmarp_ctrl), GFP_ATOMIC);
61 if (!skb)
62 return -ENOMEM;
63 ctrl = (struct atmarp_ctrl *)skb_put(skb, sizeof(struct atmarp_ctrl));
64 ctrl->type = type;
65 ctrl->itf_num = itf;
66 ctrl->ip = ip;
67 atm_force_charge(atmarpd, skb->truesize);
68
69 sk = sk_atm(atmarpd);
70 skb_queue_tail(&sk->sk_receive_queue, skb);
71 sk->sk_data_ready(sk, skb->len);
72 return 0;
73}
74
75static void link_vcc(struct clip_vcc *clip_vcc, struct atmarp_entry *entry)
76{
77 pr_debug("%p to entry %p (neigh %p)\n", clip_vcc, entry, entry->neigh);
78 clip_vcc->entry = entry;
79 clip_vcc->xoff = 0; /* @@@ may overrun buffer by one packet */
80 clip_vcc->next = entry->vccs;
81 entry->vccs = clip_vcc;
82 entry->neigh->used = jiffies;
83}
84
85static void unlink_clip_vcc(struct clip_vcc *clip_vcc)
86{
87 struct atmarp_entry *entry = clip_vcc->entry;
88 struct clip_vcc **walk;
89
90 if (!entry) {
91 pr_crit("!clip_vcc->entry (clip_vcc %p)\n", clip_vcc);
92 return;
93 }
94 netif_tx_lock_bh(entry->neigh->dev); /* block clip_start_xmit() */
95 entry->neigh->used = jiffies;
96 for (walk = &entry->vccs; *walk; walk = &(*walk)->next)
97 if (*walk == clip_vcc) {
98 int error;
99
100 *walk = clip_vcc->next; /* atomic */
101 clip_vcc->entry = NULL;
102 if (clip_vcc->xoff)
103 netif_wake_queue(entry->neigh->dev);
104 if (entry->vccs)
105 goto out;
106 entry->expires = jiffies - 1;
107 /* force resolution or expiration */
108 error = neigh_update(entry->neigh, NULL, NUD_NONE,
109 NEIGH_UPDATE_F_ADMIN);
110 if (error)
111 pr_crit("neigh_update failed with %d\n", error);
112 goto out;
113 }
114 pr_crit("ATMARP: failed (entry %p, vcc 0x%p)\n", entry, clip_vcc);
115out:
116 netif_tx_unlock_bh(entry->neigh->dev);
117}
118
119/* The neighbour entry n->lock is held. */
120static 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
154static 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
162static int clip_arp_rcv(struct sk_buff *skb)
163{
164 struct atm_vcc *vcc;
165
166 pr_debug("\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
178static 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
187static 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("\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 skb->dev->stats.rx_packets++;
218 skb->dev->stats.rx_bytes += skb->len;
219 clip_arp_rcv(skb);
220 return;
221 }
222 }
223 clip_vcc->last_use = jiffies;
224 skb->dev->stats.rx_packets++;
225 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
235static 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("(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
256static void clip_neigh_solicit(struct neighbour *neigh, struct sk_buff *skb)
257{
258 pr_debug("(neigh %p, skb %p)\n", neigh, skb);
259 to_atmarpd(act_need, PRIV(neigh->dev)->number, NEIGH2ENTRY(neigh)->ip);
260}
261
262static 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
270static const struct neigh_ops clip_neigh_ops = {
271 .family = AF_INET,
272 .solicit = clip_neigh_solicit,
273 .error_report = clip_neigh_error,
274 .output = neigh_direct_output,
275 .connected_output = neigh_direct_output,
276};
277
278static int clip_constructor(struct neighbour *neigh)
279{
280 struct atmarp_entry *entry = NEIGH2ENTRY(neigh);
281 struct net_device *dev = neigh->dev;
282 struct in_device *in_dev;
283 struct neigh_parms *parms;
284
285 pr_debug("(neigh %p, entry %p)\n", neigh, entry);
286 neigh->type = inet_addr_type(&init_net, entry->ip);
287 if (neigh->type != RTN_UNICAST)
288 return -EINVAL;
289
290 rcu_read_lock();
291 in_dev = __in_dev_get_rcu(dev);
292 if (!in_dev) {
293 rcu_read_unlock();
294 return -EINVAL;
295 }
296
297 parms = in_dev->arp_parms;
298 __neigh_parms_put(neigh->parms);
299 neigh->parms = neigh_parms_clone(parms);
300 rcu_read_unlock();
301
302 neigh->ops = &clip_neigh_ops;
303 neigh->output = neigh->nud_state & NUD_VALID ?
304 neigh->ops->connected_output : neigh->ops->output;
305 entry->neigh = neigh;
306 entry->vccs = NULL;
307 entry->expires = jiffies - 1;
308 return 0;
309}
310
311static u32 clip_hash(const void *pkey, const struct net_device *dev, __u32 rnd)
312{
313 return jhash_2words(*(u32 *) pkey, dev->ifindex, rnd);
314}
315
316static struct neigh_table clip_tbl = {
317 .family = AF_INET,
318 .entry_size = sizeof(struct neighbour)+sizeof(struct atmarp_entry),
319 .key_len = 4,
320 .hash = clip_hash,
321 .constructor = clip_constructor,
322 .id = "clip_arp_cache",
323
324 /* parameters are copied from ARP ... */
325 .parms = {
326 .tbl = &clip_tbl,
327 .base_reachable_time = 30 * HZ,
328 .retrans_time = 1 * HZ,
329 .gc_staletime = 60 * HZ,
330 .reachable_time = 30 * HZ,
331 .delay_probe_time = 5 * HZ,
332 .queue_len = 3,
333 .ucast_probes = 3,
334 .mcast_probes = 3,
335 .anycast_delay = 1 * HZ,
336 .proxy_delay = (8 * HZ) / 10,
337 .proxy_qlen = 64,
338 .locktime = 1 * HZ,
339 },
340 .gc_interval = 30 * HZ,
341 .gc_thresh1 = 128,
342 .gc_thresh2 = 512,
343 .gc_thresh3 = 1024,
344};
345
346/* @@@ copy bh locking from arp.c -- need to bh-enable atm code before */
347
348/*
349 * We play with the resolve flag: 0 and 1 have the usual meaning, but -1 means
350 * to allocate the neighbour entry but not to ask atmarpd for resolution. Also,
351 * don't increment the usage count. This is used to create entries in
352 * clip_setentry.
353 */
354
355static int clip_encap(struct atm_vcc *vcc, int mode)
356{
357 CLIP_VCC(vcc)->encap = mode;
358 return 0;
359}
360
361static netdev_tx_t clip_start_xmit(struct sk_buff *skb,
362 struct net_device *dev)
363{
364 struct clip_priv *clip_priv = PRIV(dev);
365 struct dst_entry *dst = skb_dst(skb);
366 struct atmarp_entry *entry;
367 struct neighbour *n;
368 struct atm_vcc *vcc;
369 int old;
370 unsigned long flags;
371
372 pr_debug("(skb %p)\n", skb);
373 if (!dst) {
374 pr_err("skb_dst(skb) == NULL\n");
375 dev_kfree_skb(skb);
376 dev->stats.tx_dropped++;
377 return NETDEV_TX_OK;
378 }
379 n = dst_get_neighbour(dst);
380 if (!n) {
381#if 0
382 n = clip_find_neighbour(skb_dst(skb), 1);
383 if (!n) {
384 dev_kfree_skb(skb); /* lost that one */
385 dev->stats.tx_dropped++;
386 return 0;
387 }
388 dst_set_neighbour(dst, n);
389#endif
390 pr_err("NO NEIGHBOUR !\n");
391 dev_kfree_skb(skb);
392 dev->stats.tx_dropped++;
393 return NETDEV_TX_OK;
394 }
395 entry = NEIGH2ENTRY(n);
396 if (!entry->vccs) {
397 if (time_after(jiffies, entry->expires)) {
398 /* should be resolved */
399 entry->expires = jiffies + ATMARP_RETRY_DELAY * HZ;
400 to_atmarpd(act_need, PRIV(dev)->number, entry->ip);
401 }
402 if (entry->neigh->arp_queue.qlen < ATMARP_MAX_UNRES_PACKETS)
403 skb_queue_tail(&entry->neigh->arp_queue, skb);
404 else {
405 dev_kfree_skb(skb);
406 dev->stats.tx_dropped++;
407 }
408 return NETDEV_TX_OK;
409 }
410 pr_debug("neigh %p, vccs %p\n", entry, entry->vccs);
411 ATM_SKB(skb)->vcc = vcc = entry->vccs->vcc;
412 pr_debug("using neighbour %p, vcc %p\n", n, vcc);
413 if (entry->vccs->encap) {
414 void *here;
415
416 here = skb_push(skb, RFC1483LLC_LEN);
417 memcpy(here, llc_oui, sizeof(llc_oui));
418 ((__be16 *) here)[3] = skb->protocol;
419 }
420 atomic_add(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);
421 ATM_SKB(skb)->atm_options = vcc->atm_options;
422 entry->vccs->last_use = jiffies;
423 pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, vcc, vcc->dev);
424 old = xchg(&entry->vccs->xoff, 1); /* assume XOFF ... */
425 if (old) {
426 pr_warning("XOFF->XOFF transition\n");
427 return NETDEV_TX_OK;
428 }
429 dev->stats.tx_packets++;
430 dev->stats.tx_bytes += skb->len;
431 vcc->send(vcc, skb);
432 if (atm_may_send(vcc, 0)) {
433 entry->vccs->xoff = 0;
434 return NETDEV_TX_OK;
435 }
436 spin_lock_irqsave(&clip_priv->xoff_lock, flags);
437 netif_stop_queue(dev); /* XOFF -> throttle immediately */
438 barrier();
439 if (!entry->vccs->xoff)
440 netif_start_queue(dev);
441 /* Oh, we just raced with clip_pop. netif_start_queue should be
442 good enough, because nothing should really be asleep because
443 of the brief netif_stop_queue. If this isn't true or if it
444 changes, use netif_wake_queue instead. */
445 spin_unlock_irqrestore(&clip_priv->xoff_lock, flags);
446 return NETDEV_TX_OK;
447}
448
449static int clip_mkip(struct atm_vcc *vcc, int timeout)
450{
451 struct sk_buff_head *rq, queue;
452 struct clip_vcc *clip_vcc;
453 struct sk_buff *skb, *tmp;
454 unsigned long flags;
455
456 if (!vcc->push)
457 return -EBADFD;
458 clip_vcc = kmalloc(sizeof(struct clip_vcc), GFP_KERNEL);
459 if (!clip_vcc)
460 return -ENOMEM;
461 pr_debug("%p vcc %p\n", clip_vcc, vcc);
462 clip_vcc->vcc = vcc;
463 vcc->user_back = clip_vcc;
464 set_bit(ATM_VF_IS_CLIP, &vcc->flags);
465 clip_vcc->entry = NULL;
466 clip_vcc->xoff = 0;
467 clip_vcc->encap = 1;
468 clip_vcc->last_use = jiffies;
469 clip_vcc->idle_timeout = timeout * HZ;
470 clip_vcc->old_push = vcc->push;
471 clip_vcc->old_pop = vcc->pop;
472 vcc->push = clip_push;
473 vcc->pop = clip_pop;
474
475 __skb_queue_head_init(&queue);
476 rq = &sk_atm(vcc)->sk_receive_queue;
477
478 spin_lock_irqsave(&rq->lock, flags);
479 skb_queue_splice_init(rq, &queue);
480 spin_unlock_irqrestore(&rq->lock, flags);
481
482 /* re-process everything received between connection setup and MKIP */
483 skb_queue_walk_safe(&queue, skb, tmp) {
484 if (!clip_devs) {
485 atm_return(vcc, skb->truesize);
486 kfree_skb(skb);
487 } else {
488 struct net_device *dev = skb->dev;
489 unsigned int len = skb->len;
490
491 skb_get(skb);
492 clip_push(vcc, skb);
493 dev->stats.rx_packets--;
494 dev->stats.rx_bytes -= len;
495 kfree_skb(skb);
496 }
497 }
498 return 0;
499}
500
501static int clip_setentry(struct atm_vcc *vcc, __be32 ip)
502{
503 struct neighbour *neigh;
504 struct atmarp_entry *entry;
505 int error;
506 struct clip_vcc *clip_vcc;
507 struct rtable *rt;
508
509 if (vcc->push != clip_push) {
510 pr_warning("non-CLIP VCC\n");
511 return -EBADF;
512 }
513 clip_vcc = CLIP_VCC(vcc);
514 if (!ip) {
515 if (!clip_vcc->entry) {
516 pr_err("hiding hidden ATMARP entry\n");
517 return 0;
518 }
519 pr_debug("remove\n");
520 unlink_clip_vcc(clip_vcc);
521 return 0;
522 }
523 rt = ip_route_output(&init_net, ip, 0, 1, 0);
524 if (IS_ERR(rt))
525 return PTR_ERR(rt);
526 neigh = __neigh_lookup(&clip_tbl, &ip, rt->dst.dev, 1);
527 ip_rt_put(rt);
528 if (!neigh)
529 return -ENOMEM;
530 entry = NEIGH2ENTRY(neigh);
531 if (entry != clip_vcc->entry) {
532 if (!clip_vcc->entry)
533 pr_debug("add\n");
534 else {
535 pr_debug("update\n");
536 unlink_clip_vcc(clip_vcc);
537 }
538 link_vcc(clip_vcc, entry);
539 }
540 error = neigh_update(neigh, llc_oui, NUD_PERMANENT,
541 NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN);
542 neigh_release(neigh);
543 return error;
544}
545
546static const struct net_device_ops clip_netdev_ops = {
547 .ndo_start_xmit = clip_start_xmit,
548};
549
550static void clip_setup(struct net_device *dev)
551{
552 dev->netdev_ops = &clip_netdev_ops;
553 dev->type = ARPHRD_ATM;
554 dev->hard_header_len = RFC1483LLC_LEN;
555 dev->mtu = RFC1626_MTU;
556 dev->tx_queue_len = 100; /* "normal" queue (packets) */
557 /* When using a "real" qdisc, the qdisc determines the queue */
558 /* length. tx_queue_len is only used for the default case, */
559 /* without any more elaborate queuing. 100 is a reasonable */
560 /* compromise between decent burst-tolerance and protection */
561 /* against memory hogs. */
562 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
563}
564
565static int clip_create(int number)
566{
567 struct net_device *dev;
568 struct clip_priv *clip_priv;
569 int error;
570
571 if (number != -1) {
572 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
573 if (PRIV(dev)->number == number)
574 return -EEXIST;
575 } else {
576 number = 0;
577 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
578 if (PRIV(dev)->number >= number)
579 number = PRIV(dev)->number + 1;
580 }
581 dev = alloc_netdev(sizeof(struct clip_priv), "", clip_setup);
582 if (!dev)
583 return -ENOMEM;
584 clip_priv = PRIV(dev);
585 sprintf(dev->name, "atm%d", number);
586 spin_lock_init(&clip_priv->xoff_lock);
587 clip_priv->number = number;
588 error = register_netdev(dev);
589 if (error) {
590 free_netdev(dev);
591 return error;
592 }
593 clip_priv->next = clip_devs;
594 clip_devs = dev;
595 pr_debug("registered (net:%s)\n", dev->name);
596 return number;
597}
598
599static int clip_device_event(struct notifier_block *this, unsigned long event,
600 void *arg)
601{
602 struct net_device *dev = arg;
603
604 if (!net_eq(dev_net(dev), &init_net))
605 return NOTIFY_DONE;
606
607 if (event == NETDEV_UNREGISTER) {
608 neigh_ifdown(&clip_tbl, dev);
609 return NOTIFY_DONE;
610 }
611
612 /* ignore non-CLIP devices */
613 if (dev->type != ARPHRD_ATM || dev->netdev_ops != &clip_netdev_ops)
614 return NOTIFY_DONE;
615
616 switch (event) {
617 case NETDEV_UP:
618 pr_debug("NETDEV_UP\n");
619 to_atmarpd(act_up, PRIV(dev)->number, 0);
620 break;
621 case NETDEV_GOING_DOWN:
622 pr_debug("NETDEV_DOWN\n");
623 to_atmarpd(act_down, PRIV(dev)->number, 0);
624 break;
625 case NETDEV_CHANGE:
626 case NETDEV_CHANGEMTU:
627 pr_debug("NETDEV_CHANGE*\n");
628 to_atmarpd(act_change, PRIV(dev)->number, 0);
629 break;
630 }
631 return NOTIFY_DONE;
632}
633
634static int clip_inet_event(struct notifier_block *this, unsigned long event,
635 void *ifa)
636{
637 struct in_device *in_dev;
638
639 in_dev = ((struct in_ifaddr *)ifa)->ifa_dev;
640 /*
641 * Transitions are of the down-change-up type, so it's sufficient to
642 * handle the change on up.
643 */
644 if (event != NETDEV_UP)
645 return NOTIFY_DONE;
646 return clip_device_event(this, NETDEV_CHANGE, in_dev->dev);
647}
648
649static struct notifier_block clip_dev_notifier = {
650 .notifier_call = clip_device_event,
651};
652
653
654
655static struct notifier_block clip_inet_notifier = {
656 .notifier_call = clip_inet_event,
657};
658
659
660
661static void atmarpd_close(struct atm_vcc *vcc)
662{
663 pr_debug("\n");
664
665 rtnl_lock();
666 atmarpd = NULL;
667 skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
668 rtnl_unlock();
669
670 pr_debug("(done)\n");
671 module_put(THIS_MODULE);
672}
673
674static struct atmdev_ops atmarpd_dev_ops = {
675 .close = atmarpd_close
676};
677
678
679static struct atm_dev atmarpd_dev = {
680 .ops = &atmarpd_dev_ops,
681 .type = "arpd",
682 .number = 999,
683 .lock = __SPIN_LOCK_UNLOCKED(atmarpd_dev.lock)
684};
685
686
687static int atm_init_atmarp(struct atm_vcc *vcc)
688{
689 rtnl_lock();
690 if (atmarpd) {
691 rtnl_unlock();
692 return -EADDRINUSE;
693 }
694
695 mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ);
696
697 atmarpd = vcc;
698 set_bit(ATM_VF_META, &vcc->flags);
699 set_bit(ATM_VF_READY, &vcc->flags);
700 /* allow replies and avoid getting closed if signaling dies */
701 vcc->dev = &atmarpd_dev;
702 vcc_insert_socket(sk_atm(vcc));
703 vcc->push = NULL;
704 vcc->pop = NULL; /* crash */
705 vcc->push_oam = NULL; /* crash */
706 rtnl_unlock();
707 return 0;
708}
709
710static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
711{
712 struct atm_vcc *vcc = ATM_SD(sock);
713 int err = 0;
714
715 switch (cmd) {
716 case SIOCMKCLIP:
717 case ATMARPD_CTRL:
718 case ATMARP_MKIP:
719 case ATMARP_SETENTRY:
720 case ATMARP_ENCAP:
721 if (!capable(CAP_NET_ADMIN))
722 return -EPERM;
723 break;
724 default:
725 return -ENOIOCTLCMD;
726 }
727
728 switch (cmd) {
729 case SIOCMKCLIP:
730 err = clip_create(arg);
731 break;
732 case ATMARPD_CTRL:
733 err = atm_init_atmarp(vcc);
734 if (!err) {
735 sock->state = SS_CONNECTED;
736 __module_get(THIS_MODULE);
737 }
738 break;
739 case ATMARP_MKIP:
740 err = clip_mkip(vcc, arg);
741 break;
742 case ATMARP_SETENTRY:
743 err = clip_setentry(vcc, (__force __be32)arg);
744 break;
745 case ATMARP_ENCAP:
746 err = clip_encap(vcc, arg);
747 break;
748 }
749 return err;
750}
751
752static struct atm_ioctl clip_ioctl_ops = {
753 .owner = THIS_MODULE,
754 .ioctl = clip_ioctl,
755};
756
757#ifdef CONFIG_PROC_FS
758
759static void svc_addr(struct seq_file *seq, struct sockaddr_atmsvc *addr)
760{
761 static int code[] = { 1, 2, 10, 6, 1, 0 };
762 static int e164[] = { 1, 8, 4, 6, 1, 0 };
763
764 if (*addr->sas_addr.pub) {
765 seq_printf(seq, "%s", addr->sas_addr.pub);
766 if (*addr->sas_addr.prv)
767 seq_putc(seq, '+');
768 } else if (!*addr->sas_addr.prv) {
769 seq_printf(seq, "%s", "(none)");
770 return;
771 }
772 if (*addr->sas_addr.prv) {
773 unsigned char *prv = addr->sas_addr.prv;
774 int *fields;
775 int i, j;
776
777 fields = *prv == ATM_AFI_E164 ? e164 : code;
778 for (i = 0; fields[i]; i++) {
779 for (j = fields[i]; j; j--)
780 seq_printf(seq, "%02X", *prv++);
781 if (fields[i + 1])
782 seq_putc(seq, '.');
783 }
784 }
785}
786
787/* This means the neighbour entry has no attached VCC objects. */
788#define SEQ_NO_VCC_TOKEN ((void *) 2)
789
790static void atmarp_info(struct seq_file *seq, struct net_device *dev,
791 struct atmarp_entry *entry, struct clip_vcc *clip_vcc)
792{
793 unsigned long exp;
794 char buf[17];
795 int svc, llc, off;
796
797 svc = ((clip_vcc == SEQ_NO_VCC_TOKEN) ||
798 (sk_atm(clip_vcc->vcc)->sk_family == AF_ATMSVC));
799
800 llc = ((clip_vcc == SEQ_NO_VCC_TOKEN) || clip_vcc->encap);
801
802 if (clip_vcc == SEQ_NO_VCC_TOKEN)
803 exp = entry->neigh->used;
804 else
805 exp = clip_vcc->last_use;
806
807 exp = (jiffies - exp) / HZ;
808
809 seq_printf(seq, "%-6s%-4s%-4s%5ld ",
810 dev->name, svc ? "SVC" : "PVC", llc ? "LLC" : "NULL", exp);
811
812 off = scnprintf(buf, sizeof(buf) - 1, "%pI4",
813 &entry->ip);
814 while (off < 16)
815 buf[off++] = ' ';
816 buf[off] = '\0';
817 seq_printf(seq, "%s", buf);
818
819 if (clip_vcc == SEQ_NO_VCC_TOKEN) {
820 if (time_before(jiffies, entry->expires))
821 seq_printf(seq, "(resolving)\n");
822 else
823 seq_printf(seq, "(expired, ref %d)\n",
824 atomic_read(&entry->neigh->refcnt));
825 } else if (!svc) {
826 seq_printf(seq, "%d.%d.%d\n",
827 clip_vcc->vcc->dev->number,
828 clip_vcc->vcc->vpi, clip_vcc->vcc->vci);
829 } else {
830 svc_addr(seq, &clip_vcc->vcc->remote);
831 seq_putc(seq, '\n');
832 }
833}
834
835struct clip_seq_state {
836 /* This member must be first. */
837 struct neigh_seq_state ns;
838
839 /* Local to clip specific iteration. */
840 struct clip_vcc *vcc;
841};
842
843static struct clip_vcc *clip_seq_next_vcc(struct atmarp_entry *e,
844 struct clip_vcc *curr)
845{
846 if (!curr) {
847 curr = e->vccs;
848 if (!curr)
849 return SEQ_NO_VCC_TOKEN;
850 return curr;
851 }
852 if (curr == SEQ_NO_VCC_TOKEN)
853 return NULL;
854
855 curr = curr->next;
856
857 return curr;
858}
859
860static void *clip_seq_vcc_walk(struct clip_seq_state *state,
861 struct atmarp_entry *e, loff_t * pos)
862{
863 struct clip_vcc *vcc = state->vcc;
864
865 vcc = clip_seq_next_vcc(e, vcc);
866 if (vcc && pos != NULL) {
867 while (*pos) {
868 vcc = clip_seq_next_vcc(e, vcc);
869 if (!vcc)
870 break;
871 --(*pos);
872 }
873 }
874 state->vcc = vcc;
875
876 return vcc;
877}
878
879static void *clip_seq_sub_iter(struct neigh_seq_state *_state,
880 struct neighbour *n, loff_t * pos)
881{
882 struct clip_seq_state *state = (struct clip_seq_state *)_state;
883
884 return clip_seq_vcc_walk(state, NEIGH2ENTRY(n), pos);
885}
886
887static void *clip_seq_start(struct seq_file *seq, loff_t * pos)
888{
889 struct clip_seq_state *state = seq->private;
890 state->ns.neigh_sub_iter = clip_seq_sub_iter;
891 return neigh_seq_start(seq, pos, &clip_tbl, NEIGH_SEQ_NEIGH_ONLY);
892}
893
894static int clip_seq_show(struct seq_file *seq, void *v)
895{
896 static char atm_arp_banner[] =
897 "IPitf TypeEncp Idle IP address ATM address\n";
898
899 if (v == SEQ_START_TOKEN) {
900 seq_puts(seq, atm_arp_banner);
901 } else {
902 struct clip_seq_state *state = seq->private;
903 struct neighbour *n = v;
904 struct clip_vcc *vcc = state->vcc;
905
906 atmarp_info(seq, n->dev, NEIGH2ENTRY(n), vcc);
907 }
908 return 0;
909}
910
911static const struct seq_operations arp_seq_ops = {
912 .start = clip_seq_start,
913 .next = neigh_seq_next,
914 .stop = neigh_seq_stop,
915 .show = clip_seq_show,
916};
917
918static int arp_seq_open(struct inode *inode, struct file *file)
919{
920 return seq_open_net(inode, file, &arp_seq_ops,
921 sizeof(struct clip_seq_state));
922}
923
924static const struct file_operations arp_seq_fops = {
925 .open = arp_seq_open,
926 .read = seq_read,
927 .llseek = seq_lseek,
928 .release = seq_release_net,
929 .owner = THIS_MODULE
930};
931#endif
932
933static void atm_clip_exit_noproc(void);
934
935static int __init atm_clip_init(void)
936{
937 neigh_table_init_no_netlink(&clip_tbl);
938
939 clip_tbl_hook = &clip_tbl;
940 register_atm_ioctl(&clip_ioctl_ops);
941 register_netdevice_notifier(&clip_dev_notifier);
942 register_inetaddr_notifier(&clip_inet_notifier);
943
944 setup_timer(&idle_timer, idle_timer_check, 0);
945
946#ifdef CONFIG_PROC_FS
947 {
948 struct proc_dir_entry *p;
949
950 p = proc_create("arp", S_IRUGO, atm_proc_root, &arp_seq_fops);
951 if (!p) {
952 pr_err("Unable to initialize /proc/net/atm/arp\n");
953 atm_clip_exit_noproc();
954 return -ENOMEM;
955 }
956 }
957#endif
958
959 return 0;
960}
961
962static void atm_clip_exit_noproc(void)
963{
964 struct net_device *dev, *next;
965
966 unregister_inetaddr_notifier(&clip_inet_notifier);
967 unregister_netdevice_notifier(&clip_dev_notifier);
968
969 deregister_atm_ioctl(&clip_ioctl_ops);
970
971 /* First, stop the idle timer, so it stops banging
972 * on the table.
973 */
974 del_timer_sync(&idle_timer);
975
976 /* Next, purge the table, so that the device
977 * unregister loop below does not hang due to
978 * device references remaining in the table.
979 */
980 neigh_ifdown(&clip_tbl, NULL);
981
982 dev = clip_devs;
983 while (dev) {
984 next = PRIV(dev)->next;
985 unregister_netdev(dev);
986 free_netdev(dev);
987 dev = next;
988 }
989
990 /* Now it is safe to fully shutdown whole table. */
991 neigh_table_clear(&clip_tbl);
992
993 clip_tbl_hook = NULL;
994}
995
996static void __exit atm_clip_exit(void)
997{
998 remove_proc_entry("arp", atm_proc_root);
999
1000 atm_clip_exit_noproc();
1001}
1002
1003module_init(atm_clip_init);
1004module_exit(atm_clip_exit);
1005MODULE_AUTHOR("Werner Almesberger");
1006MODULE_DESCRIPTION("Classical/IP over ATM interface");
1007MODULE_LICENSE("GPL");
1/* net/atm/clip.c - RFC1577 Classical IP over ATM */
2
3/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
4
5#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
6
7#include <linux/string.h>
8#include <linux/errno.h>
9#include <linux/kernel.h> /* for UINT_MAX */
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/netdevice.h>
13#include <linux/skbuff.h>
14#include <linux/wait.h>
15#include <linux/timer.h>
16#include <linux/if_arp.h> /* for some manifest constants */
17#include <linux/notifier.h>
18#include <linux/atm.h>
19#include <linux/atmdev.h>
20#include <linux/atmclip.h>
21#include <linux/atmarp.h>
22#include <linux/capability.h>
23#include <linux/ip.h> /* for net/route.h */
24#include <linux/in.h> /* for struct sockaddr_in */
25#include <linux/if.h> /* for IFF_UP */
26#include <linux/inetdevice.h>
27#include <linux/bitops.h>
28#include <linux/poison.h>
29#include <linux/proc_fs.h>
30#include <linux/seq_file.h>
31#include <linux/rcupdate.h>
32#include <linux/jhash.h>
33#include <linux/slab.h>
34#include <net/route.h> /* for struct rtable and routing */
35#include <net/icmp.h> /* icmp_send */
36#include <net/arp.h>
37#include <linux/param.h> /* for HZ */
38#include <linux/uaccess.h>
39#include <asm/byteorder.h> /* for htons etc. */
40#include <linux/atomic.h>
41
42#include "common.h"
43#include "resources.h"
44#include <net/atmclip.h>
45
46static struct net_device *clip_devs;
47static struct atm_vcc *atmarpd;
48static struct timer_list idle_timer;
49static const struct neigh_ops clip_neigh_ops;
50
51static int to_atmarpd(enum atmarp_ctrl_type type, int itf, __be32 ip)
52{
53 struct sock *sk;
54 struct atmarp_ctrl *ctrl;
55 struct sk_buff *skb;
56
57 pr_debug("(%d)\n", type);
58 if (!atmarpd)
59 return -EUNATCH;
60 skb = alloc_skb(sizeof(struct atmarp_ctrl), GFP_ATOMIC);
61 if (!skb)
62 return -ENOMEM;
63 ctrl = (struct atmarp_ctrl *)skb_put(skb, sizeof(struct atmarp_ctrl));
64 ctrl->type = type;
65 ctrl->itf_num = itf;
66 ctrl->ip = ip;
67 atm_force_charge(atmarpd, skb->truesize);
68
69 sk = sk_atm(atmarpd);
70 skb_queue_tail(&sk->sk_receive_queue, skb);
71 sk->sk_data_ready(sk);
72 return 0;
73}
74
75static void link_vcc(struct clip_vcc *clip_vcc, struct atmarp_entry *entry)
76{
77 pr_debug("%p to entry %p (neigh %p)\n", clip_vcc, entry, entry->neigh);
78 clip_vcc->entry = entry;
79 clip_vcc->xoff = 0; /* @@@ may overrun buffer by one packet */
80 clip_vcc->next = entry->vccs;
81 entry->vccs = clip_vcc;
82 entry->neigh->used = jiffies;
83}
84
85static void unlink_clip_vcc(struct clip_vcc *clip_vcc)
86{
87 struct atmarp_entry *entry = clip_vcc->entry;
88 struct clip_vcc **walk;
89
90 if (!entry) {
91 pr_crit("!clip_vcc->entry (clip_vcc %p)\n", clip_vcc);
92 return;
93 }
94 netif_tx_lock_bh(entry->neigh->dev); /* block clip_start_xmit() */
95 entry->neigh->used = jiffies;
96 for (walk = &entry->vccs; *walk; walk = &(*walk)->next)
97 if (*walk == clip_vcc) {
98 int error;
99
100 *walk = clip_vcc->next; /* atomic */
101 clip_vcc->entry = NULL;
102 if (clip_vcc->xoff)
103 netif_wake_queue(entry->neigh->dev);
104 if (entry->vccs)
105 goto out;
106 entry->expires = jiffies - 1;
107 /* force resolution or expiration */
108 error = neigh_update(entry->neigh, NULL, NUD_NONE,
109 NEIGH_UPDATE_F_ADMIN);
110 if (error)
111 pr_crit("neigh_update failed with %d\n", error);
112 goto out;
113 }
114 pr_crit("ATMARP: failed (entry %p, vcc 0x%p)\n", entry, clip_vcc);
115out:
116 netif_tx_unlock_bh(entry->neigh->dev);
117}
118
119/* The neighbour entry n->lock is held. */
120static int neigh_check_cb(struct neighbour *n)
121{
122 struct atmarp_entry *entry = neighbour_priv(n);
123 struct clip_vcc *cv;
124
125 if (n->ops != &clip_neigh_ops)
126 return 0;
127 for (cv = entry->vccs; cv; cv = cv->next) {
128 unsigned long exp = cv->last_use + cv->idle_timeout;
129
130 if (cv->idle_timeout && time_after(jiffies, exp)) {
131 pr_debug("releasing vcc %p->%p of entry %p\n",
132 cv, cv->vcc, entry);
133 vcc_release_async(cv->vcc, -ETIMEDOUT);
134 }
135 }
136
137 if (entry->vccs || time_before(jiffies, entry->expires))
138 return 0;
139
140 if (atomic_read(&n->refcnt) > 1) {
141 struct sk_buff *skb;
142
143 pr_debug("destruction postponed with ref %d\n",
144 atomic_read(&n->refcnt));
145
146 while ((skb = skb_dequeue(&n->arp_queue)) != NULL)
147 dev_kfree_skb(skb);
148
149 return 0;
150 }
151
152 pr_debug("expired neigh %p\n", n);
153 return 1;
154}
155
156static void idle_timer_check(unsigned long dummy)
157{
158 write_lock(&arp_tbl.lock);
159 __neigh_for_each_release(&arp_tbl, neigh_check_cb);
160 mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ);
161 write_unlock(&arp_tbl.lock);
162}
163
164static int clip_arp_rcv(struct sk_buff *skb)
165{
166 struct atm_vcc *vcc;
167
168 pr_debug("\n");
169 vcc = ATM_SKB(skb)->vcc;
170 if (!vcc || !atm_charge(vcc, skb->truesize)) {
171 dev_kfree_skb_any(skb);
172 return 0;
173 }
174 pr_debug("pushing to %p\n", vcc);
175 pr_debug("using %p\n", CLIP_VCC(vcc)->old_push);
176 CLIP_VCC(vcc)->old_push(vcc, skb);
177 return 0;
178}
179
180static const unsigned char llc_oui[] = {
181 0xaa, /* DSAP: non-ISO */
182 0xaa, /* SSAP: non-ISO */
183 0x03, /* Ctrl: Unnumbered Information Command PDU */
184 0x00, /* OUI: EtherType */
185 0x00,
186 0x00
187};
188
189static void clip_push(struct atm_vcc *vcc, struct sk_buff *skb)
190{
191 struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
192
193 pr_debug("\n");
194
195 if (!clip_devs) {
196 atm_return(vcc, skb->truesize);
197 kfree_skb(skb);
198 return;
199 }
200
201 if (!skb) {
202 pr_debug("removing VCC %p\n", clip_vcc);
203 if (clip_vcc->entry)
204 unlink_clip_vcc(clip_vcc);
205 clip_vcc->old_push(vcc, NULL); /* pass on the bad news */
206 kfree(clip_vcc);
207 return;
208 }
209 atm_return(vcc, skb->truesize);
210 skb->dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : clip_devs;
211 /* clip_vcc->entry == NULL if we don't have an IP address yet */
212 if (!skb->dev) {
213 dev_kfree_skb_any(skb);
214 return;
215 }
216 ATM_SKB(skb)->vcc = vcc;
217 skb_reset_mac_header(skb);
218 if (!clip_vcc->encap ||
219 skb->len < RFC1483LLC_LEN ||
220 memcmp(skb->data, llc_oui, sizeof(llc_oui)))
221 skb->protocol = htons(ETH_P_IP);
222 else {
223 skb->protocol = ((__be16 *)skb->data)[3];
224 skb_pull(skb, RFC1483LLC_LEN);
225 if (skb->protocol == htons(ETH_P_ARP)) {
226 skb->dev->stats.rx_packets++;
227 skb->dev->stats.rx_bytes += skb->len;
228 clip_arp_rcv(skb);
229 return;
230 }
231 }
232 clip_vcc->last_use = jiffies;
233 skb->dev->stats.rx_packets++;
234 skb->dev->stats.rx_bytes += skb->len;
235 memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
236 netif_rx(skb);
237}
238
239/*
240 * Note: these spinlocks _must_not_ block on non-SMP. The only goal is that
241 * clip_pop is atomic with respect to the critical section in clip_start_xmit.
242 */
243
244static void clip_pop(struct atm_vcc *vcc, struct sk_buff *skb)
245{
246 struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
247 struct net_device *dev = skb->dev;
248 int old;
249 unsigned long flags;
250
251 pr_debug("(vcc %p)\n", vcc);
252 clip_vcc->old_pop(vcc, skb);
253 /* skb->dev == NULL in outbound ARP packets */
254 if (!dev)
255 return;
256 spin_lock_irqsave(&PRIV(dev)->xoff_lock, flags);
257 if (atm_may_send(vcc, 0)) {
258 old = xchg(&clip_vcc->xoff, 0);
259 if (old)
260 netif_wake_queue(dev);
261 }
262 spin_unlock_irqrestore(&PRIV(dev)->xoff_lock, flags);
263}
264
265static void clip_neigh_solicit(struct neighbour *neigh, struct sk_buff *skb)
266{
267 __be32 *ip = (__be32 *) neigh->primary_key;
268
269 pr_debug("(neigh %p, skb %p)\n", neigh, skb);
270 to_atmarpd(act_need, PRIV(neigh->dev)->number, *ip);
271}
272
273static void clip_neigh_error(struct neighbour *neigh, struct sk_buff *skb)
274{
275#ifndef CONFIG_ATM_CLIP_NO_ICMP
276 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
277#endif
278 kfree_skb(skb);
279}
280
281static const struct neigh_ops clip_neigh_ops = {
282 .family = AF_INET,
283 .solicit = clip_neigh_solicit,
284 .error_report = clip_neigh_error,
285 .output = neigh_direct_output,
286 .connected_output = neigh_direct_output,
287};
288
289static int clip_constructor(struct neighbour *neigh)
290{
291 struct atmarp_entry *entry = neighbour_priv(neigh);
292
293 if (neigh->tbl->family != AF_INET)
294 return -EINVAL;
295
296 if (neigh->type != RTN_UNICAST)
297 return -EINVAL;
298
299 neigh->nud_state = NUD_NONE;
300 neigh->ops = &clip_neigh_ops;
301 neigh->output = neigh->ops->output;
302 entry->neigh = neigh;
303 entry->vccs = NULL;
304 entry->expires = jiffies - 1;
305
306 return 0;
307}
308
309/* @@@ copy bh locking from arp.c -- need to bh-enable atm code before */
310
311/*
312 * We play with the resolve flag: 0 and 1 have the usual meaning, but -1 means
313 * to allocate the neighbour entry but not to ask atmarpd for resolution. Also,
314 * don't increment the usage count. This is used to create entries in
315 * clip_setentry.
316 */
317
318static int clip_encap(struct atm_vcc *vcc, int mode)
319{
320 CLIP_VCC(vcc)->encap = mode;
321 return 0;
322}
323
324static netdev_tx_t clip_start_xmit(struct sk_buff *skb,
325 struct net_device *dev)
326{
327 struct clip_priv *clip_priv = PRIV(dev);
328 struct dst_entry *dst = skb_dst(skb);
329 struct atmarp_entry *entry;
330 struct neighbour *n;
331 struct atm_vcc *vcc;
332 struct rtable *rt;
333 __be32 *daddr;
334 int old;
335 unsigned long flags;
336
337 pr_debug("(skb %p)\n", skb);
338 if (!dst) {
339 pr_err("skb_dst(skb) == NULL\n");
340 dev_kfree_skb(skb);
341 dev->stats.tx_dropped++;
342 return NETDEV_TX_OK;
343 }
344 rt = (struct rtable *) dst;
345 if (rt->rt_gateway)
346 daddr = &rt->rt_gateway;
347 else
348 daddr = &ip_hdr(skb)->daddr;
349 n = dst_neigh_lookup(dst, daddr);
350 if (!n) {
351 pr_err("NO NEIGHBOUR !\n");
352 dev_kfree_skb(skb);
353 dev->stats.tx_dropped++;
354 return NETDEV_TX_OK;
355 }
356 entry = neighbour_priv(n);
357 if (!entry->vccs) {
358 if (time_after(jiffies, entry->expires)) {
359 /* should be resolved */
360 entry->expires = jiffies + ATMARP_RETRY_DELAY * HZ;
361 to_atmarpd(act_need, PRIV(dev)->number, *((__be32 *)n->primary_key));
362 }
363 if (entry->neigh->arp_queue.qlen < ATMARP_MAX_UNRES_PACKETS)
364 skb_queue_tail(&entry->neigh->arp_queue, skb);
365 else {
366 dev_kfree_skb(skb);
367 dev->stats.tx_dropped++;
368 }
369 goto out_release_neigh;
370 }
371 pr_debug("neigh %p, vccs %p\n", entry, entry->vccs);
372 ATM_SKB(skb)->vcc = vcc = entry->vccs->vcc;
373 pr_debug("using neighbour %p, vcc %p\n", n, vcc);
374 if (entry->vccs->encap) {
375 void *here;
376
377 here = skb_push(skb, RFC1483LLC_LEN);
378 memcpy(here, llc_oui, sizeof(llc_oui));
379 ((__be16 *) here)[3] = skb->protocol;
380 }
381 atomic_add(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);
382 ATM_SKB(skb)->atm_options = vcc->atm_options;
383 entry->vccs->last_use = jiffies;
384 pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, vcc, vcc->dev);
385 old = xchg(&entry->vccs->xoff, 1); /* assume XOFF ... */
386 if (old) {
387 pr_warning("XOFF->XOFF transition\n");
388 goto out_release_neigh;
389 }
390 dev->stats.tx_packets++;
391 dev->stats.tx_bytes += skb->len;
392 vcc->send(vcc, skb);
393 if (atm_may_send(vcc, 0)) {
394 entry->vccs->xoff = 0;
395 goto out_release_neigh;
396 }
397 spin_lock_irqsave(&clip_priv->xoff_lock, flags);
398 netif_stop_queue(dev); /* XOFF -> throttle immediately */
399 barrier();
400 if (!entry->vccs->xoff)
401 netif_start_queue(dev);
402 /* Oh, we just raced with clip_pop. netif_start_queue should be
403 good enough, because nothing should really be asleep because
404 of the brief netif_stop_queue. If this isn't true or if it
405 changes, use netif_wake_queue instead. */
406 spin_unlock_irqrestore(&clip_priv->xoff_lock, flags);
407out_release_neigh:
408 neigh_release(n);
409 return NETDEV_TX_OK;
410}
411
412static int clip_mkip(struct atm_vcc *vcc, int timeout)
413{
414 struct clip_vcc *clip_vcc;
415
416 if (!vcc->push)
417 return -EBADFD;
418 clip_vcc = kmalloc(sizeof(struct clip_vcc), GFP_KERNEL);
419 if (!clip_vcc)
420 return -ENOMEM;
421 pr_debug("%p vcc %p\n", clip_vcc, vcc);
422 clip_vcc->vcc = vcc;
423 vcc->user_back = clip_vcc;
424 set_bit(ATM_VF_IS_CLIP, &vcc->flags);
425 clip_vcc->entry = NULL;
426 clip_vcc->xoff = 0;
427 clip_vcc->encap = 1;
428 clip_vcc->last_use = jiffies;
429 clip_vcc->idle_timeout = timeout * HZ;
430 clip_vcc->old_push = vcc->push;
431 clip_vcc->old_pop = vcc->pop;
432 vcc->push = clip_push;
433 vcc->pop = clip_pop;
434
435 /* re-process everything received between connection setup and MKIP */
436 vcc_process_recv_queue(vcc);
437
438 return 0;
439}
440
441static int clip_setentry(struct atm_vcc *vcc, __be32 ip)
442{
443 struct neighbour *neigh;
444 struct atmarp_entry *entry;
445 int error;
446 struct clip_vcc *clip_vcc;
447 struct rtable *rt;
448
449 if (vcc->push != clip_push) {
450 pr_warning("non-CLIP VCC\n");
451 return -EBADF;
452 }
453 clip_vcc = CLIP_VCC(vcc);
454 if (!ip) {
455 if (!clip_vcc->entry) {
456 pr_err("hiding hidden ATMARP entry\n");
457 return 0;
458 }
459 pr_debug("remove\n");
460 unlink_clip_vcc(clip_vcc);
461 return 0;
462 }
463 rt = ip_route_output(&init_net, ip, 0, 1, 0);
464 if (IS_ERR(rt))
465 return PTR_ERR(rt);
466 neigh = __neigh_lookup(&arp_tbl, &ip, rt->dst.dev, 1);
467 ip_rt_put(rt);
468 if (!neigh)
469 return -ENOMEM;
470 entry = neighbour_priv(neigh);
471 if (entry != clip_vcc->entry) {
472 if (!clip_vcc->entry)
473 pr_debug("add\n");
474 else {
475 pr_debug("update\n");
476 unlink_clip_vcc(clip_vcc);
477 }
478 link_vcc(clip_vcc, entry);
479 }
480 error = neigh_update(neigh, llc_oui, NUD_PERMANENT,
481 NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN);
482 neigh_release(neigh);
483 return error;
484}
485
486static const struct net_device_ops clip_netdev_ops = {
487 .ndo_start_xmit = clip_start_xmit,
488 .ndo_neigh_construct = clip_constructor,
489};
490
491static void clip_setup(struct net_device *dev)
492{
493 dev->netdev_ops = &clip_netdev_ops;
494 dev->type = ARPHRD_ATM;
495 dev->neigh_priv_len = sizeof(struct atmarp_entry);
496 dev->hard_header_len = RFC1483LLC_LEN;
497 dev->mtu = RFC1626_MTU;
498 dev->tx_queue_len = 100; /* "normal" queue (packets) */
499 /* When using a "real" qdisc, the qdisc determines the queue */
500 /* length. tx_queue_len is only used for the default case, */
501 /* without any more elaborate queuing. 100 is a reasonable */
502 /* compromise between decent burst-tolerance and protection */
503 /* against memory hogs. */
504 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
505}
506
507static int clip_create(int number)
508{
509 struct net_device *dev;
510 struct clip_priv *clip_priv;
511 int error;
512
513 if (number != -1) {
514 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
515 if (PRIV(dev)->number == number)
516 return -EEXIST;
517 } else {
518 number = 0;
519 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
520 if (PRIV(dev)->number >= number)
521 number = PRIV(dev)->number + 1;
522 }
523 dev = alloc_netdev(sizeof(struct clip_priv), "", clip_setup);
524 if (!dev)
525 return -ENOMEM;
526 clip_priv = PRIV(dev);
527 sprintf(dev->name, "atm%d", number);
528 spin_lock_init(&clip_priv->xoff_lock);
529 clip_priv->number = number;
530 error = register_netdev(dev);
531 if (error) {
532 free_netdev(dev);
533 return error;
534 }
535 clip_priv->next = clip_devs;
536 clip_devs = dev;
537 pr_debug("registered (net:%s)\n", dev->name);
538 return number;
539}
540
541static int clip_device_event(struct notifier_block *this, unsigned long event,
542 void *ptr)
543{
544 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
545
546 if (!net_eq(dev_net(dev), &init_net))
547 return NOTIFY_DONE;
548
549 if (event == NETDEV_UNREGISTER)
550 return NOTIFY_DONE;
551
552 /* ignore non-CLIP devices */
553 if (dev->type != ARPHRD_ATM || dev->netdev_ops != &clip_netdev_ops)
554 return NOTIFY_DONE;
555
556 switch (event) {
557 case NETDEV_UP:
558 pr_debug("NETDEV_UP\n");
559 to_atmarpd(act_up, PRIV(dev)->number, 0);
560 break;
561 case NETDEV_GOING_DOWN:
562 pr_debug("NETDEV_DOWN\n");
563 to_atmarpd(act_down, PRIV(dev)->number, 0);
564 break;
565 case NETDEV_CHANGE:
566 case NETDEV_CHANGEMTU:
567 pr_debug("NETDEV_CHANGE*\n");
568 to_atmarpd(act_change, PRIV(dev)->number, 0);
569 break;
570 }
571 return NOTIFY_DONE;
572}
573
574static int clip_inet_event(struct notifier_block *this, unsigned long event,
575 void *ifa)
576{
577 struct in_device *in_dev;
578 struct netdev_notifier_info info;
579
580 in_dev = ((struct in_ifaddr *)ifa)->ifa_dev;
581 /*
582 * Transitions are of the down-change-up type, so it's sufficient to
583 * handle the change on up.
584 */
585 if (event != NETDEV_UP)
586 return NOTIFY_DONE;
587 netdev_notifier_info_init(&info, in_dev->dev);
588 return clip_device_event(this, NETDEV_CHANGE, &info);
589}
590
591static struct notifier_block clip_dev_notifier = {
592 .notifier_call = clip_device_event,
593};
594
595
596
597static struct notifier_block clip_inet_notifier = {
598 .notifier_call = clip_inet_event,
599};
600
601
602
603static void atmarpd_close(struct atm_vcc *vcc)
604{
605 pr_debug("\n");
606
607 rtnl_lock();
608 atmarpd = NULL;
609 skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
610 rtnl_unlock();
611
612 pr_debug("(done)\n");
613 module_put(THIS_MODULE);
614}
615
616static struct atmdev_ops atmarpd_dev_ops = {
617 .close = atmarpd_close
618};
619
620
621static struct atm_dev atmarpd_dev = {
622 .ops = &atmarpd_dev_ops,
623 .type = "arpd",
624 .number = 999,
625 .lock = __SPIN_LOCK_UNLOCKED(atmarpd_dev.lock)
626};
627
628
629static int atm_init_atmarp(struct atm_vcc *vcc)
630{
631 rtnl_lock();
632 if (atmarpd) {
633 rtnl_unlock();
634 return -EADDRINUSE;
635 }
636
637 mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ);
638
639 atmarpd = vcc;
640 set_bit(ATM_VF_META, &vcc->flags);
641 set_bit(ATM_VF_READY, &vcc->flags);
642 /* allow replies and avoid getting closed if signaling dies */
643 vcc->dev = &atmarpd_dev;
644 vcc_insert_socket(sk_atm(vcc));
645 vcc->push = NULL;
646 vcc->pop = NULL; /* crash */
647 vcc->push_oam = NULL; /* crash */
648 rtnl_unlock();
649 return 0;
650}
651
652static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
653{
654 struct atm_vcc *vcc = ATM_SD(sock);
655 int err = 0;
656
657 switch (cmd) {
658 case SIOCMKCLIP:
659 case ATMARPD_CTRL:
660 case ATMARP_MKIP:
661 case ATMARP_SETENTRY:
662 case ATMARP_ENCAP:
663 if (!capable(CAP_NET_ADMIN))
664 return -EPERM;
665 break;
666 default:
667 return -ENOIOCTLCMD;
668 }
669
670 switch (cmd) {
671 case SIOCMKCLIP:
672 err = clip_create(arg);
673 break;
674 case ATMARPD_CTRL:
675 err = atm_init_atmarp(vcc);
676 if (!err) {
677 sock->state = SS_CONNECTED;
678 __module_get(THIS_MODULE);
679 }
680 break;
681 case ATMARP_MKIP:
682 err = clip_mkip(vcc, arg);
683 break;
684 case ATMARP_SETENTRY:
685 err = clip_setentry(vcc, (__force __be32)arg);
686 break;
687 case ATMARP_ENCAP:
688 err = clip_encap(vcc, arg);
689 break;
690 }
691 return err;
692}
693
694static struct atm_ioctl clip_ioctl_ops = {
695 .owner = THIS_MODULE,
696 .ioctl = clip_ioctl,
697};
698
699#ifdef CONFIG_PROC_FS
700
701static void svc_addr(struct seq_file *seq, struct sockaddr_atmsvc *addr)
702{
703 static int code[] = { 1, 2, 10, 6, 1, 0 };
704 static int e164[] = { 1, 8, 4, 6, 1, 0 };
705
706 if (*addr->sas_addr.pub) {
707 seq_printf(seq, "%s", addr->sas_addr.pub);
708 if (*addr->sas_addr.prv)
709 seq_putc(seq, '+');
710 } else if (!*addr->sas_addr.prv) {
711 seq_printf(seq, "%s", "(none)");
712 return;
713 }
714 if (*addr->sas_addr.prv) {
715 unsigned char *prv = addr->sas_addr.prv;
716 int *fields;
717 int i, j;
718
719 fields = *prv == ATM_AFI_E164 ? e164 : code;
720 for (i = 0; fields[i]; i++) {
721 for (j = fields[i]; j; j--)
722 seq_printf(seq, "%02X", *prv++);
723 if (fields[i + 1])
724 seq_putc(seq, '.');
725 }
726 }
727}
728
729/* This means the neighbour entry has no attached VCC objects. */
730#define SEQ_NO_VCC_TOKEN ((void *) 2)
731
732static void atmarp_info(struct seq_file *seq, struct neighbour *n,
733 struct atmarp_entry *entry, struct clip_vcc *clip_vcc)
734{
735 struct net_device *dev = n->dev;
736 unsigned long exp;
737 char buf[17];
738 int svc, llc, off;
739
740 svc = ((clip_vcc == SEQ_NO_VCC_TOKEN) ||
741 (sk_atm(clip_vcc->vcc)->sk_family == AF_ATMSVC));
742
743 llc = ((clip_vcc == SEQ_NO_VCC_TOKEN) || clip_vcc->encap);
744
745 if (clip_vcc == SEQ_NO_VCC_TOKEN)
746 exp = entry->neigh->used;
747 else
748 exp = clip_vcc->last_use;
749
750 exp = (jiffies - exp) / HZ;
751
752 seq_printf(seq, "%-6s%-4s%-4s%5ld ",
753 dev->name, svc ? "SVC" : "PVC", llc ? "LLC" : "NULL", exp);
754
755 off = scnprintf(buf, sizeof(buf) - 1, "%pI4", n->primary_key);
756 while (off < 16)
757 buf[off++] = ' ';
758 buf[off] = '\0';
759 seq_printf(seq, "%s", buf);
760
761 if (clip_vcc == SEQ_NO_VCC_TOKEN) {
762 if (time_before(jiffies, entry->expires))
763 seq_printf(seq, "(resolving)\n");
764 else
765 seq_printf(seq, "(expired, ref %d)\n",
766 atomic_read(&entry->neigh->refcnt));
767 } else if (!svc) {
768 seq_printf(seq, "%d.%d.%d\n",
769 clip_vcc->vcc->dev->number,
770 clip_vcc->vcc->vpi, clip_vcc->vcc->vci);
771 } else {
772 svc_addr(seq, &clip_vcc->vcc->remote);
773 seq_putc(seq, '\n');
774 }
775}
776
777struct clip_seq_state {
778 /* This member must be first. */
779 struct neigh_seq_state ns;
780
781 /* Local to clip specific iteration. */
782 struct clip_vcc *vcc;
783};
784
785static struct clip_vcc *clip_seq_next_vcc(struct atmarp_entry *e,
786 struct clip_vcc *curr)
787{
788 if (!curr) {
789 curr = e->vccs;
790 if (!curr)
791 return SEQ_NO_VCC_TOKEN;
792 return curr;
793 }
794 if (curr == SEQ_NO_VCC_TOKEN)
795 return NULL;
796
797 curr = curr->next;
798
799 return curr;
800}
801
802static void *clip_seq_vcc_walk(struct clip_seq_state *state,
803 struct atmarp_entry *e, loff_t * pos)
804{
805 struct clip_vcc *vcc = state->vcc;
806
807 vcc = clip_seq_next_vcc(e, vcc);
808 if (vcc && pos != NULL) {
809 while (*pos) {
810 vcc = clip_seq_next_vcc(e, vcc);
811 if (!vcc)
812 break;
813 --(*pos);
814 }
815 }
816 state->vcc = vcc;
817
818 return vcc;
819}
820
821static void *clip_seq_sub_iter(struct neigh_seq_state *_state,
822 struct neighbour *n, loff_t * pos)
823{
824 struct clip_seq_state *state = (struct clip_seq_state *)_state;
825
826 if (n->dev->type != ARPHRD_ATM)
827 return NULL;
828
829 return clip_seq_vcc_walk(state, neighbour_priv(n), pos);
830}
831
832static void *clip_seq_start(struct seq_file *seq, loff_t * pos)
833{
834 struct clip_seq_state *state = seq->private;
835 state->ns.neigh_sub_iter = clip_seq_sub_iter;
836 return neigh_seq_start(seq, pos, &arp_tbl, NEIGH_SEQ_NEIGH_ONLY);
837}
838
839static int clip_seq_show(struct seq_file *seq, void *v)
840{
841 static char atm_arp_banner[] =
842 "IPitf TypeEncp Idle IP address ATM address\n";
843
844 if (v == SEQ_START_TOKEN) {
845 seq_puts(seq, atm_arp_banner);
846 } else {
847 struct clip_seq_state *state = seq->private;
848 struct clip_vcc *vcc = state->vcc;
849 struct neighbour *n = v;
850
851 atmarp_info(seq, n, neighbour_priv(n), vcc);
852 }
853 return 0;
854}
855
856static const struct seq_operations arp_seq_ops = {
857 .start = clip_seq_start,
858 .next = neigh_seq_next,
859 .stop = neigh_seq_stop,
860 .show = clip_seq_show,
861};
862
863static int arp_seq_open(struct inode *inode, struct file *file)
864{
865 return seq_open_net(inode, file, &arp_seq_ops,
866 sizeof(struct clip_seq_state));
867}
868
869static const struct file_operations arp_seq_fops = {
870 .open = arp_seq_open,
871 .read = seq_read,
872 .llseek = seq_lseek,
873 .release = seq_release_net,
874 .owner = THIS_MODULE
875};
876#endif
877
878static void atm_clip_exit_noproc(void);
879
880static int __init atm_clip_init(void)
881{
882 register_atm_ioctl(&clip_ioctl_ops);
883 register_netdevice_notifier(&clip_dev_notifier);
884 register_inetaddr_notifier(&clip_inet_notifier);
885
886 setup_timer(&idle_timer, idle_timer_check, 0);
887
888#ifdef CONFIG_PROC_FS
889 {
890 struct proc_dir_entry *p;
891
892 p = proc_create("arp", S_IRUGO, atm_proc_root, &arp_seq_fops);
893 if (!p) {
894 pr_err("Unable to initialize /proc/net/atm/arp\n");
895 atm_clip_exit_noproc();
896 return -ENOMEM;
897 }
898 }
899#endif
900
901 return 0;
902}
903
904static void atm_clip_exit_noproc(void)
905{
906 struct net_device *dev, *next;
907
908 unregister_inetaddr_notifier(&clip_inet_notifier);
909 unregister_netdevice_notifier(&clip_dev_notifier);
910
911 deregister_atm_ioctl(&clip_ioctl_ops);
912
913 /* First, stop the idle timer, so it stops banging
914 * on the table.
915 */
916 del_timer_sync(&idle_timer);
917
918 dev = clip_devs;
919 while (dev) {
920 next = PRIV(dev)->next;
921 unregister_netdev(dev);
922 free_netdev(dev);
923 dev = next;
924 }
925}
926
927static void __exit atm_clip_exit(void)
928{
929 remove_proc_entry("arp", atm_proc_root);
930
931 atm_clip_exit_noproc();
932}
933
934module_init(atm_clip_init);
935module_exit(atm_clip_exit);
936MODULE_AUTHOR("Werner Almesberger");
937MODULE_DESCRIPTION("Classical/IP over ATM interface");
938MODULE_LICENSE("GPL");