[PATCH] mark struct file_operations const 7
[linux-3.10.git] / net / atm / clip.c
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
44 #if 0
45 #define DPRINTK(format,args...) printk(format,##args)
46 #else
47 #define DPRINTK(format,args...)
48 #endif
49
50
51 static struct net_device *clip_devs;
52 static struct atm_vcc *atmarpd;
53 static struct neigh_table clip_tbl;
54 static struct timer_list idle_timer;
55
56 static int to_atmarpd(enum atmarp_ctrl_type type, int itf, __be32 ip)
57 {
58         struct sock *sk;
59         struct atmarp_ctrl *ctrl;
60         struct sk_buff *skb;
61
62         DPRINTK("to_atmarpd(%d)\n", type);
63         if (!atmarpd)
64                 return -EUNATCH;
65         skb = alloc_skb(sizeof(struct atmarp_ctrl),GFP_ATOMIC);
66         if (!skb)
67                 return -ENOMEM;
68         ctrl = (struct atmarp_ctrl *) skb_put(skb,sizeof(struct atmarp_ctrl));
69         ctrl->type = type;
70         ctrl->itf_num = itf;
71         ctrl->ip = ip;
72         atm_force_charge(atmarpd, skb->truesize);
73
74         sk = sk_atm(atmarpd);
75         skb_queue_tail(&sk->sk_receive_queue, skb);
76         sk->sk_data_ready(sk, skb->len);
77         return 0;
78 }
79
80 static void link_vcc(struct clip_vcc *clip_vcc, struct atmarp_entry *entry)
81 {
82         DPRINTK("link_vcc %p to entry %p (neigh %p)\n", clip_vcc, entry,
83                 entry->neigh);
84         clip_vcc->entry = entry;
85         clip_vcc->xoff = 0;     /* @@@ may overrun buffer by one packet */
86         clip_vcc->next = entry->vccs;
87         entry->vccs = clip_vcc;
88         entry->neigh->used = jiffies;
89 }
90
91 static void unlink_clip_vcc(struct clip_vcc *clip_vcc)
92 {
93         struct atmarp_entry *entry = clip_vcc->entry;
94         struct clip_vcc **walk;
95
96         if (!entry) {
97                 printk(KERN_CRIT "!clip_vcc->entry (clip_vcc %p)\n", clip_vcc);
98                 return;
99         }
100         netif_tx_lock_bh(entry->neigh->dev);    /* block clip_start_xmit() */
101         entry->neigh->used = jiffies;
102         for (walk = &entry->vccs; *walk; walk = &(*walk)->next)
103                 if (*walk == clip_vcc) {
104                         int error;
105
106                         *walk = clip_vcc->next; /* atomic */
107                         clip_vcc->entry = NULL;
108                         if (clip_vcc->xoff)
109                                 netif_wake_queue(entry->neigh->dev);
110                         if (entry->vccs)
111                                 goto out;
112                         entry->expires = jiffies - 1;
113                         /* force resolution or expiration */
114                         error = neigh_update(entry->neigh, NULL, NUD_NONE,
115                                              NEIGH_UPDATE_F_ADMIN);
116                         if (error)
117                                 printk(KERN_CRIT "unlink_clip_vcc: "
118                                        "neigh_update failed with %d\n", error);
119                         goto out;
120                 }
121         printk(KERN_CRIT "ATMARP: unlink_clip_vcc failed (entry %p, vcc "
122                "0x%p)\n", entry, clip_vcc);
123       out:
124         netif_tx_unlock_bh(entry->neigh->dev);
125 }
126
127 /* The neighbour entry n->lock is held. */
128 static int neigh_check_cb(struct neighbour *n)
129 {
130         struct atmarp_entry *entry = NEIGH2ENTRY(n);
131         struct clip_vcc *cv;
132
133         for (cv = entry->vccs; cv; cv = cv->next) {
134                 unsigned long exp = cv->last_use + cv->idle_timeout;
135
136                 if (cv->idle_timeout && time_after(jiffies, exp)) {
137                         DPRINTK("releasing vcc %p->%p of entry %p\n",
138                                 cv, cv->vcc, entry);
139                         vcc_release_async(cv->vcc, -ETIMEDOUT);
140                 }
141         }
142
143         if (entry->vccs || time_before(jiffies, entry->expires))
144                 return 0;
145
146         if (atomic_read(&n->refcnt) > 1) {
147                 struct sk_buff *skb;
148
149                 DPRINTK("destruction postponed with ref %d\n",
150                         atomic_read(&n->refcnt));
151
152                 while ((skb = skb_dequeue(&n->arp_queue)) != NULL)
153                         dev_kfree_skb(skb);
154
155                 return 0;
156         }
157
158         DPRINTK("expired neigh %p\n", n);
159         return 1;
160 }
161
162 static void idle_timer_check(unsigned long dummy)
163 {
164         write_lock(&clip_tbl.lock);
165         __neigh_for_each_release(&clip_tbl, neigh_check_cb);
166         mod_timer(&idle_timer, jiffies + CLIP_CHECK_INTERVAL * HZ);
167         write_unlock(&clip_tbl.lock);
168 }
169
170 static int clip_arp_rcv(struct sk_buff *skb)
171 {
172         struct atm_vcc *vcc;
173
174         DPRINTK("clip_arp_rcv\n");
175         vcc = ATM_SKB(skb)->vcc;
176         if (!vcc || !atm_charge(vcc, skb->truesize)) {
177                 dev_kfree_skb_any(skb);
178                 return 0;
179         }
180         DPRINTK("pushing to %p\n", vcc);
181         DPRINTK("using %p\n", CLIP_VCC(vcc)->old_push);
182         CLIP_VCC(vcc)->old_push(vcc, skb);
183         return 0;
184 }
185
186 static const unsigned char llc_oui[] = {
187         0xaa,   /* DSAP: non-ISO */
188         0xaa,   /* SSAP: non-ISO */
189         0x03,   /* Ctrl: Unnumbered Information Command PDU */
190         0x00,   /* OUI: EtherType */
191         0x00,
192         0x00
193 };
194
195 static void clip_push(struct atm_vcc *vcc, struct sk_buff *skb)
196 {
197         struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
198
199         DPRINTK("clip push\n");
200         if (!skb) {
201                 DPRINTK("removing VCC %p\n", clip_vcc);
202                 if (clip_vcc->entry)
203                         unlink_clip_vcc(clip_vcc);
204                 clip_vcc->old_push(vcc, NULL);  /* pass on the bad news */
205                 kfree(clip_vcc);
206                 return;
207         }
208         atm_return(vcc, skb->truesize);
209         skb->dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : clip_devs;
210         /* clip_vcc->entry == NULL if we don't have an IP address yet */
211         if (!skb->dev) {
212                 dev_kfree_skb_any(skb);
213                 return;
214         }
215         ATM_SKB(skb)->vcc = vcc;
216         skb->mac.raw = skb->data;
217         if (!clip_vcc->encap
218             || skb->len < RFC1483LLC_LEN
219             || memcmp(skb->data, llc_oui, sizeof (llc_oui)))
220                 skb->protocol = htons(ETH_P_IP);
221         else {
222                 skb->protocol = ((__be16 *) skb->data)[3];
223                 skb_pull(skb, RFC1483LLC_LEN);
224                 if (skb->protocol == htons(ETH_P_ARP)) {
225                         PRIV(skb->dev)->stats.rx_packets++;
226                         PRIV(skb->dev)->stats.rx_bytes += skb->len;
227                         clip_arp_rcv(skb);
228                         return;
229                 }
230         }
231         clip_vcc->last_use = jiffies;
232         PRIV(skb->dev)->stats.rx_packets++;
233         PRIV(skb->dev)->stats.rx_bytes += skb->len;
234         memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
235         netif_rx(skb);
236 }
237
238 /*
239  * Note: these spinlocks _must_not_ block on non-SMP. The only goal is that
240  * clip_pop is atomic with respect to the critical section in clip_start_xmit.
241  */
242
243 static void clip_pop(struct atm_vcc *vcc, struct sk_buff *skb)
244 {
245         struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
246         struct net_device *dev = skb->dev;
247         int old;
248         unsigned long flags;
249
250         DPRINTK("clip_pop(vcc %p)\n", vcc);
251         clip_vcc->old_pop(vcc, skb);
252         /* skb->dev == NULL in outbound ARP packets */
253         if (!dev)
254                 return;
255         spin_lock_irqsave(&PRIV(dev)->xoff_lock, flags);
256         if (atm_may_send(vcc, 0)) {
257                 old = xchg(&clip_vcc->xoff, 0);
258                 if (old)
259                         netif_wake_queue(dev);
260         }
261         spin_unlock_irqrestore(&PRIV(dev)->xoff_lock, flags);
262 }
263
264 static void clip_neigh_destroy(struct neighbour *neigh)
265 {
266         DPRINTK("clip_neigh_destroy (neigh %p)\n", neigh);
267         if (NEIGH2ENTRY(neigh)->vccs)
268                 printk(KERN_CRIT "clip_neigh_destroy: vccs != NULL !!!\n");
269         NEIGH2ENTRY(neigh)->vccs = (void *) NEIGHBOR_DEAD;
270 }
271
272 static void clip_neigh_solicit(struct neighbour *neigh, struct sk_buff *skb)
273 {
274         DPRINTK("clip_neigh_solicit (neigh %p, skb %p)\n", neigh, skb);
275         to_atmarpd(act_need, PRIV(neigh->dev)->number, NEIGH2ENTRY(neigh)->ip);
276 }
277
278 static void clip_neigh_error(struct neighbour *neigh, struct sk_buff *skb)
279 {
280 #ifndef CONFIG_ATM_CLIP_NO_ICMP
281         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
282 #endif
283         kfree_skb(skb);
284 }
285
286 static struct neigh_ops clip_neigh_ops = {
287         .family =               AF_INET,
288         .solicit =              clip_neigh_solicit,
289         .error_report =         clip_neigh_error,
290         .output =               dev_queue_xmit,
291         .connected_output =     dev_queue_xmit,
292         .hh_output =            dev_queue_xmit,
293         .queue_xmit =           dev_queue_xmit,
294 };
295
296 static int clip_constructor(struct neighbour *neigh)
297 {
298         struct atmarp_entry *entry = NEIGH2ENTRY(neigh);
299         struct net_device *dev = neigh->dev;
300         struct in_device *in_dev;
301         struct neigh_parms *parms;
302
303         DPRINTK("clip_constructor (neigh %p, entry %p)\n", neigh, entry);
304         neigh->type = inet_addr_type(entry->ip);
305         if (neigh->type != RTN_UNICAST)
306                 return -EINVAL;
307
308         rcu_read_lock();
309         in_dev = __in_dev_get_rcu(dev);
310         if (!in_dev) {
311                 rcu_read_unlock();
312                 return -EINVAL;
313         }
314
315         parms = in_dev->arp_parms;
316         __neigh_parms_put(neigh->parms);
317         neigh->parms = neigh_parms_clone(parms);
318         rcu_read_unlock();
319
320         neigh->ops = &clip_neigh_ops;
321         neigh->output = neigh->nud_state & NUD_VALID ?
322             neigh->ops->connected_output : neigh->ops->output;
323         entry->neigh = neigh;
324         entry->vccs = NULL;
325         entry->expires = jiffies - 1;
326         return 0;
327 }
328
329 static u32 clip_hash(const void *pkey, const struct net_device *dev)
330 {
331         return jhash_2words(*(u32 *) pkey, dev->ifindex, clip_tbl.hash_rnd);
332 }
333
334 static struct neigh_table clip_tbl = {
335         .family         = AF_INET,
336         .entry_size     = sizeof(struct neighbour)+sizeof(struct atmarp_entry),
337         .key_len        = 4,
338         .hash           = clip_hash,
339         .constructor    = clip_constructor,
340         .id             = "clip_arp_cache",
341
342         /* parameters are copied from ARP ... */
343         .parms = {
344                 .tbl                    = &clip_tbl,
345                 .neigh_destructor       = clip_neigh_destroy,
346                 .base_reachable_time    = 30 * HZ,
347                 .retrans_time           = 1 * HZ,
348                 .gc_staletime           = 60 * HZ,
349                 .reachable_time         = 30 * HZ,
350                 .delay_probe_time       = 5 * HZ,
351                 .queue_len              = 3,
352                 .ucast_probes           = 3,
353                 .mcast_probes           = 3,
354                 .anycast_delay          = 1 * HZ,
355                 .proxy_delay            = (8 * HZ) / 10,
356                 .proxy_qlen             = 64,
357                 .locktime               = 1 * HZ,
358         },
359         .gc_interval    = 30 * HZ,
360         .gc_thresh1     = 128,
361         .gc_thresh2     = 512,
362         .gc_thresh3     = 1024,
363 };
364
365 /* @@@ copy bh locking from arp.c -- need to bh-enable atm code before */
366
367 /*
368  * We play with the resolve flag: 0 and 1 have the usual meaning, but -1 means
369  * to allocate the neighbour entry but not to ask atmarpd for resolution. Also,
370  * don't increment the usage count. This is used to create entries in
371  * clip_setentry.
372  */
373
374 static int clip_encap(struct atm_vcc *vcc, int mode)
375 {
376         CLIP_VCC(vcc)->encap = mode;
377         return 0;
378 }
379
380 static int clip_start_xmit(struct sk_buff *skb, struct net_device *dev)
381 {
382         struct clip_priv *clip_priv = PRIV(dev);
383         struct atmarp_entry *entry;
384         struct atm_vcc *vcc;
385         int old;
386         unsigned long flags;
387
388         DPRINTK("clip_start_xmit (skb %p)\n", skb);
389         if (!skb->dst) {
390                 printk(KERN_ERR "clip_start_xmit: skb->dst == NULL\n");
391                 dev_kfree_skb(skb);
392                 clip_priv->stats.tx_dropped++;
393                 return 0;
394         }
395         if (!skb->dst->neighbour) {
396 #if 0
397                 skb->dst->neighbour = clip_find_neighbour(skb->dst, 1);
398                 if (!skb->dst->neighbour) {
399                         dev_kfree_skb(skb);     /* lost that one */
400                         clip_priv->stats.tx_dropped++;
401                         return 0;
402                 }
403 #endif
404                 printk(KERN_ERR "clip_start_xmit: NO NEIGHBOUR !\n");
405                 dev_kfree_skb(skb);
406                 clip_priv->stats.tx_dropped++;
407                 return 0;
408         }
409         entry = NEIGH2ENTRY(skb->dst->neighbour);
410         if (!entry->vccs) {
411                 if (time_after(jiffies, entry->expires)) {
412                         /* should be resolved */
413                         entry->expires = jiffies + ATMARP_RETRY_DELAY * HZ;
414                         to_atmarpd(act_need, PRIV(dev)->number, entry->ip);
415                 }
416                 if (entry->neigh->arp_queue.qlen < ATMARP_MAX_UNRES_PACKETS)
417                         skb_queue_tail(&entry->neigh->arp_queue, skb);
418                 else {
419                         dev_kfree_skb(skb);
420                         clip_priv->stats.tx_dropped++;
421                 }
422                 return 0;
423         }
424         DPRINTK("neigh %p, vccs %p\n", entry, entry->vccs);
425         ATM_SKB(skb)->vcc = vcc = entry->vccs->vcc;
426         DPRINTK("using neighbour %p, vcc %p\n", skb->dst->neighbour, vcc);
427         if (entry->vccs->encap) {
428                 void *here;
429
430                 here = skb_push(skb, RFC1483LLC_LEN);
431                 memcpy(here, llc_oui, sizeof(llc_oui));
432                 ((__be16 *) here)[3] = skb->protocol;
433         }
434         atomic_add(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);
435         ATM_SKB(skb)->atm_options = vcc->atm_options;
436         entry->vccs->last_use = jiffies;
437         DPRINTK("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, vcc, vcc->dev);
438         old = xchg(&entry->vccs->xoff, 1);      /* assume XOFF ... */
439         if (old) {
440                 printk(KERN_WARNING "clip_start_xmit: XOFF->XOFF transition\n");
441                 return 0;
442         }
443         clip_priv->stats.tx_packets++;
444         clip_priv->stats.tx_bytes += skb->len;
445         vcc->send(vcc, skb);
446         if (atm_may_send(vcc, 0)) {
447                 entry->vccs->xoff = 0;
448                 return 0;
449         }
450         spin_lock_irqsave(&clip_priv->xoff_lock, flags);
451         netif_stop_queue(dev);  /* XOFF -> throttle immediately */
452         barrier();
453         if (!entry->vccs->xoff)
454                 netif_start_queue(dev);
455         /* Oh, we just raced with clip_pop. netif_start_queue should be
456            good enough, because nothing should really be asleep because
457            of the brief netif_stop_queue. If this isn't true or if it
458            changes, use netif_wake_queue instead. */
459         spin_unlock_irqrestore(&clip_priv->xoff_lock, flags);
460         return 0;
461 }
462
463 static struct net_device_stats *clip_get_stats(struct net_device *dev)
464 {
465         return &PRIV(dev)->stats;
466 }
467
468 static int clip_mkip(struct atm_vcc *vcc, int timeout)
469 {
470         struct clip_vcc *clip_vcc;
471         struct sk_buff *skb;
472         struct sk_buff_head *rq;
473         unsigned long flags;
474
475         if (!vcc->push)
476                 return -EBADFD;
477         clip_vcc = kmalloc(sizeof(struct clip_vcc), GFP_KERNEL);
478         if (!clip_vcc)
479                 return -ENOMEM;
480         DPRINTK("mkip clip_vcc %p vcc %p\n", clip_vcc, vcc);
481         clip_vcc->vcc = vcc;
482         vcc->user_back = clip_vcc;
483         set_bit(ATM_VF_IS_CLIP, &vcc->flags);
484         clip_vcc->entry = NULL;
485         clip_vcc->xoff = 0;
486         clip_vcc->encap = 1;
487         clip_vcc->last_use = jiffies;
488         clip_vcc->idle_timeout = timeout * HZ;
489         clip_vcc->old_push = vcc->push;
490         clip_vcc->old_pop = vcc->pop;
491         vcc->push = clip_push;
492         vcc->pop = clip_pop;
493
494         rq = &sk_atm(vcc)->sk_receive_queue;
495
496         spin_lock_irqsave(&rq->lock, flags);
497         if (skb_queue_empty(rq)) {
498                 skb = NULL;
499         } else {
500                 /* NULL terminate the list.  */
501                 rq->prev->next = NULL;
502                 skb = rq->next;
503         }
504         rq->prev = rq->next = (struct sk_buff *)rq;
505         rq->qlen = 0;
506         spin_unlock_irqrestore(&rq->lock, flags);
507
508         /* re-process everything received between connection setup and MKIP */
509         while (skb) {
510                 struct sk_buff *next = skb->next;
511
512                 skb->next = skb->prev = NULL;
513                 if (!clip_devs) {
514                         atm_return(vcc, skb->truesize);
515                         kfree_skb(skb);
516                 } else {
517                         unsigned int len = skb->len;
518
519                         skb_get(skb);
520                         clip_push(vcc, skb);
521                         PRIV(skb->dev)->stats.rx_packets--;
522                         PRIV(skb->dev)->stats.rx_bytes -= len;
523                         kfree_skb(skb);
524                 }
525
526                 skb = next;
527         }
528         return 0;
529 }
530
531 static int clip_setentry(struct atm_vcc *vcc, __be32 ip)
532 {
533         struct neighbour *neigh;
534         struct atmarp_entry *entry;
535         int error;
536         struct clip_vcc *clip_vcc;
537         struct flowi fl = { .nl_u = { .ip4_u = { .daddr = ip, .tos = 1}} };
538         struct rtable *rt;
539
540         if (vcc->push != clip_push) {
541                 printk(KERN_WARNING "clip_setentry: non-CLIP VCC\n");
542                 return -EBADF;
543         }
544         clip_vcc = CLIP_VCC(vcc);
545         if (!ip) {
546                 if (!clip_vcc->entry) {
547                         printk(KERN_ERR "hiding hidden ATMARP entry\n");
548                         return 0;
549                 }
550                 DPRINTK("setentry: remove\n");
551                 unlink_clip_vcc(clip_vcc);
552                 return 0;
553         }
554         error = ip_route_output_key(&rt, &fl);
555         if (error)
556                 return error;
557         neigh = __neigh_lookup(&clip_tbl, &ip, rt->u.dst.dev, 1);
558         ip_rt_put(rt);
559         if (!neigh)
560                 return -ENOMEM;
561         entry = NEIGH2ENTRY(neigh);
562         if (entry != clip_vcc->entry) {
563                 if (!clip_vcc->entry)
564                         DPRINTK("setentry: add\n");
565                 else {
566                         DPRINTK("setentry: update\n");
567                         unlink_clip_vcc(clip_vcc);
568                 }
569                 link_vcc(clip_vcc, entry);
570         }
571         error = neigh_update(neigh, llc_oui, NUD_PERMANENT,
572                              NEIGH_UPDATE_F_OVERRIDE | NEIGH_UPDATE_F_ADMIN);
573         neigh_release(neigh);
574         return error;
575 }
576
577 static void clip_setup(struct net_device *dev)
578 {
579         dev->hard_start_xmit = clip_start_xmit;
580         /* sg_xmit ... */
581         dev->get_stats = clip_get_stats;
582         dev->type = ARPHRD_ATM;
583         dev->hard_header_len = RFC1483LLC_LEN;
584         dev->mtu = RFC1626_MTU;
585         dev->tx_queue_len = 100;        /* "normal" queue (packets) */
586         /* When using a "real" qdisc, the qdisc determines the queue */
587         /* length. tx_queue_len is only used for the default case, */
588         /* without any more elaborate queuing. 100 is a reasonable */
589         /* compromise between decent burst-tolerance and protection */
590         /* against memory hogs. */
591 }
592
593 static int clip_create(int number)
594 {
595         struct net_device *dev;
596         struct clip_priv *clip_priv;
597         int error;
598
599         if (number != -1) {
600                 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
601                         if (PRIV(dev)->number == number)
602                                 return -EEXIST;
603         } else {
604                 number = 0;
605                 for (dev = clip_devs; dev; dev = PRIV(dev)->next)
606                         if (PRIV(dev)->number >= number)
607                                 number = PRIV(dev)->number + 1;
608         }
609         dev = alloc_netdev(sizeof(struct clip_priv), "", clip_setup);
610         if (!dev)
611                 return -ENOMEM;
612         clip_priv = PRIV(dev);
613         sprintf(dev->name, "atm%d", number);
614         spin_lock_init(&clip_priv->xoff_lock);
615         clip_priv->number = number;
616         error = register_netdev(dev);
617         if (error) {
618                 free_netdev(dev);
619                 return error;
620         }
621         clip_priv->next = clip_devs;
622         clip_devs = dev;
623         DPRINTK("registered (net:%s)\n", dev->name);
624         return number;
625 }
626
627 static int clip_device_event(struct notifier_block *this, unsigned long event,
628                              void *arg)
629 {
630         struct net_device *dev = arg;
631
632         if (event == NETDEV_UNREGISTER) {
633                 neigh_ifdown(&clip_tbl, dev);
634                 return NOTIFY_DONE;
635         }
636
637         /* ignore non-CLIP devices */
638         if (dev->type != ARPHRD_ATM || dev->hard_start_xmit != clip_start_xmit)
639                 return NOTIFY_DONE;
640
641         switch (event) {
642         case NETDEV_UP:
643                 DPRINTK("clip_device_event NETDEV_UP\n");
644                 to_atmarpd(act_up, PRIV(dev)->number, 0);
645                 break;
646         case NETDEV_GOING_DOWN:
647                 DPRINTK("clip_device_event NETDEV_DOWN\n");
648                 to_atmarpd(act_down, PRIV(dev)->number, 0);
649                 break;
650         case NETDEV_CHANGE:
651         case NETDEV_CHANGEMTU:
652                 DPRINTK("clip_device_event NETDEV_CHANGE*\n");
653                 to_atmarpd(act_change, PRIV(dev)->number, 0);
654                 break;
655         }
656         return NOTIFY_DONE;
657 }
658
659 static int clip_inet_event(struct notifier_block *this, unsigned long event,
660                            void *ifa)
661 {
662         struct in_device *in_dev;
663
664         in_dev = ((struct in_ifaddr *)ifa)->ifa_dev;
665         if (!in_dev || !in_dev->dev) {
666                 printk(KERN_WARNING "clip_inet_event: no device\n");
667                 return NOTIFY_DONE;
668         }
669         /*
670          * Transitions are of the down-change-up type, so it's sufficient to
671          * handle the change on up.
672          */
673         if (event != NETDEV_UP)
674                 return NOTIFY_DONE;
675         return clip_device_event(this, NETDEV_CHANGE, in_dev->dev);
676 }
677
678
679 static struct notifier_block clip_dev_notifier = {
680         .notifier_call = clip_device_event,
681 };
682
683
684
685 static struct notifier_block clip_inet_notifier = {
686         .notifier_call = clip_inet_event,
687 };
688
689
690
691 static void atmarpd_close(struct atm_vcc *vcc)
692 {
693         DPRINTK("atmarpd_close\n");
694
695         rtnl_lock();
696         atmarpd = NULL;
697         skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
698         rtnl_unlock();
699
700         DPRINTK("(done)\n");
701         module_put(THIS_MODULE);
702 }
703
704
705 static struct atmdev_ops atmarpd_dev_ops = {
706         .close = atmarpd_close
707 };
708
709
710 static struct atm_dev atmarpd_dev = {
711         .ops =                  &atmarpd_dev_ops,
712         .type =                 "arpd",
713         .number =               999,
714         .lock =                 SPIN_LOCK_UNLOCKED
715 };
716
717
718 static int atm_init_atmarp(struct atm_vcc *vcc)
719 {
720         rtnl_lock();
721         if (atmarpd) {
722                 rtnl_unlock();
723                 return -EADDRINUSE;
724         }
725
726         mod_timer(&idle_timer, jiffies+CLIP_CHECK_INTERVAL*HZ);
727
728         atmarpd = vcc;
729         set_bit(ATM_VF_META,&vcc->flags);
730         set_bit(ATM_VF_READY,&vcc->flags);
731             /* allow replies and avoid getting closed if signaling dies */
732         vcc->dev = &atmarpd_dev;
733         vcc_insert_socket(sk_atm(vcc));
734         vcc->push = NULL;
735         vcc->pop = NULL; /* crash */
736         vcc->push_oam = NULL; /* crash */
737         rtnl_unlock();
738         return 0;
739 }
740
741 static int clip_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
742 {
743         struct atm_vcc *vcc = ATM_SD(sock);
744         int err = 0;
745
746         switch (cmd) {
747         case SIOCMKCLIP:
748         case ATMARPD_CTRL:
749         case ATMARP_MKIP:
750         case ATMARP_SETENTRY:
751         case ATMARP_ENCAP:
752                 if (!capable(CAP_NET_ADMIN))
753                         return -EPERM;
754                 break;
755         default:
756                 return -ENOIOCTLCMD;
757         }
758
759         switch (cmd) {
760         case SIOCMKCLIP:
761                 err = clip_create(arg);
762                 break;
763         case ATMARPD_CTRL:
764                 err = atm_init_atmarp(vcc);
765                 if (!err) {
766                         sock->state = SS_CONNECTED;
767                         __module_get(THIS_MODULE);
768                 }
769                 break;
770         case ATMARP_MKIP:
771                 err = clip_mkip(vcc, arg);
772                 break;
773         case ATMARP_SETENTRY:
774                 err = clip_setentry(vcc, (__force __be32)arg);
775                 break;
776         case ATMARP_ENCAP:
777                 err = clip_encap(vcc, arg);
778                 break;
779         }
780         return err;
781 }
782
783 static struct atm_ioctl clip_ioctl_ops = {
784         .owner = THIS_MODULE,
785         .ioctl = clip_ioctl,
786 };
787
788 #ifdef CONFIG_PROC_FS
789
790 static void svc_addr(struct seq_file *seq, struct sockaddr_atmsvc *addr)
791 {
792         static int code[] = { 1, 2, 10, 6, 1, 0 };
793         static int e164[] = { 1, 8, 4, 6, 1, 0 };
794
795         if (*addr->sas_addr.pub) {
796                 seq_printf(seq, "%s", addr->sas_addr.pub);
797                 if (*addr->sas_addr.prv)
798                         seq_putc(seq, '+');
799         } else if (!*addr->sas_addr.prv) {
800                 seq_printf(seq, "%s", "(none)");
801                 return;
802         }
803         if (*addr->sas_addr.prv) {
804                 unsigned char *prv = addr->sas_addr.prv;
805                 int *fields;
806                 int i, j;
807
808                 fields = *prv == ATM_AFI_E164 ? e164 : code;
809                 for (i = 0; fields[i]; i++) {
810                         for (j = fields[i]; j; j--)
811                                 seq_printf(seq, "%02X", *prv++);
812                         if (fields[i + 1])
813                                 seq_putc(seq, '.');
814                 }
815         }
816 }
817
818 /* This means the neighbour entry has no attached VCC objects. */
819 #define SEQ_NO_VCC_TOKEN        ((void *) 2)
820
821 static void atmarp_info(struct seq_file *seq, struct net_device *dev,
822                         struct atmarp_entry *entry, struct clip_vcc *clip_vcc)
823 {
824         unsigned long exp;
825         char buf[17];
826         int svc, llc, off;
827
828         svc = ((clip_vcc == SEQ_NO_VCC_TOKEN) ||
829                (sk_atm(clip_vcc->vcc)->sk_family == AF_ATMSVC));
830
831         llc = ((clip_vcc == SEQ_NO_VCC_TOKEN) || clip_vcc->encap);
832
833         if (clip_vcc == SEQ_NO_VCC_TOKEN)
834                 exp = entry->neigh->used;
835         else
836                 exp = clip_vcc->last_use;
837
838         exp = (jiffies - exp) / HZ;
839
840         seq_printf(seq, "%-6s%-4s%-4s%5ld ",
841                    dev->name, svc ? "SVC" : "PVC", llc ? "LLC" : "NULL", exp);
842
843         off = scnprintf(buf, sizeof(buf) - 1, "%d.%d.%d.%d",
844                         NIPQUAD(entry->ip));
845         while (off < 16)
846                 buf[off++] = ' ';
847         buf[off] = '\0';
848         seq_printf(seq, "%s", buf);
849
850         if (clip_vcc == SEQ_NO_VCC_TOKEN) {
851                 if (time_before(jiffies, entry->expires))
852                         seq_printf(seq, "(resolving)\n");
853                 else
854                         seq_printf(seq, "(expired, ref %d)\n",
855                                    atomic_read(&entry->neigh->refcnt));
856         } else if (!svc) {
857                 seq_printf(seq, "%d.%d.%d\n",
858                            clip_vcc->vcc->dev->number,
859                            clip_vcc->vcc->vpi, clip_vcc->vcc->vci);
860         } else {
861                 svc_addr(seq, &clip_vcc->vcc->remote);
862                 seq_putc(seq, '\n');
863         }
864 }
865
866 struct clip_seq_state {
867         /* This member must be first. */
868         struct neigh_seq_state ns;
869
870         /* Local to clip specific iteration. */
871         struct clip_vcc *vcc;
872 };
873
874 static struct clip_vcc *clip_seq_next_vcc(struct atmarp_entry *e,
875                                           struct clip_vcc *curr)
876 {
877         if (!curr) {
878                 curr = e->vccs;
879                 if (!curr)
880                         return SEQ_NO_VCC_TOKEN;
881                 return curr;
882         }
883         if (curr == SEQ_NO_VCC_TOKEN)
884                 return NULL;
885
886         curr = curr->next;
887
888         return curr;
889 }
890
891 static void *clip_seq_vcc_walk(struct clip_seq_state *state,
892                                struct atmarp_entry *e, loff_t * pos)
893 {
894         struct clip_vcc *vcc = state->vcc;
895
896         vcc = clip_seq_next_vcc(e, vcc);
897         if (vcc && pos != NULL) {
898                 while (*pos) {
899                         vcc = clip_seq_next_vcc(e, vcc);
900                         if (!vcc)
901                                 break;
902                         --(*pos);
903                 }
904         }
905         state->vcc = vcc;
906
907         return vcc;
908 }
909
910 static void *clip_seq_sub_iter(struct neigh_seq_state *_state,
911                                struct neighbour *n, loff_t * pos)
912 {
913         struct clip_seq_state *state = (struct clip_seq_state *)_state;
914
915         return clip_seq_vcc_walk(state, NEIGH2ENTRY(n), pos);
916 }
917
918 static void *clip_seq_start(struct seq_file *seq, loff_t * pos)
919 {
920         return neigh_seq_start(seq, pos, &clip_tbl, NEIGH_SEQ_NEIGH_ONLY);
921 }
922
923 static int clip_seq_show(struct seq_file *seq, void *v)
924 {
925         static char atm_arp_banner[] =
926             "IPitf TypeEncp Idle IP address      ATM address\n";
927
928         if (v == SEQ_START_TOKEN) {
929                 seq_puts(seq, atm_arp_banner);
930         } else {
931                 struct clip_seq_state *state = seq->private;
932                 struct neighbour *n = v;
933                 struct clip_vcc *vcc = state->vcc;
934
935                 atmarp_info(seq, n->dev, NEIGH2ENTRY(n), vcc);
936         }
937         return 0;
938 }
939
940 static struct seq_operations arp_seq_ops = {
941         .start  = clip_seq_start,
942         .next   = neigh_seq_next,
943         .stop   = neigh_seq_stop,
944         .show   = clip_seq_show,
945 };
946
947 static int arp_seq_open(struct inode *inode, struct file *file)
948 {
949         struct clip_seq_state *state;
950         struct seq_file *seq;
951         int rc = -EAGAIN;
952
953         state = kzalloc(sizeof(*state), GFP_KERNEL);
954         if (!state) {
955                 rc = -ENOMEM;
956                 goto out_kfree;
957         }
958         state->ns.neigh_sub_iter = clip_seq_sub_iter;
959
960         rc = seq_open(file, &arp_seq_ops);
961         if (rc)
962                 goto out_kfree;
963
964         seq = file->private_data;
965         seq->private = state;
966 out:
967         return rc;
968
969 out_kfree:
970         kfree(state);
971         goto out;
972 }
973
974 static const struct file_operations arp_seq_fops = {
975         .open           = arp_seq_open,
976         .read           = seq_read,
977         .llseek         = seq_lseek,
978         .release        = seq_release_private,
979         .owner          = THIS_MODULE
980 };
981 #endif
982
983 static int __init atm_clip_init(void)
984 {
985         neigh_table_init_no_netlink(&clip_tbl);
986
987         clip_tbl_hook = &clip_tbl;
988         register_atm_ioctl(&clip_ioctl_ops);
989         register_netdevice_notifier(&clip_dev_notifier);
990         register_inetaddr_notifier(&clip_inet_notifier);
991
992         setup_timer(&idle_timer, idle_timer_check, 0);
993
994 #ifdef CONFIG_PROC_FS
995         {
996                 struct proc_dir_entry *p;
997
998                 p = create_proc_entry("arp", S_IRUGO, atm_proc_root);
999                 if (p)
1000                         p->proc_fops = &arp_seq_fops;
1001         }
1002 #endif
1003
1004         return 0;
1005 }
1006
1007 static void __exit atm_clip_exit(void)
1008 {
1009         struct net_device *dev, *next;
1010
1011         remove_proc_entry("arp", atm_proc_root);
1012
1013         unregister_inetaddr_notifier(&clip_inet_notifier);
1014         unregister_netdevice_notifier(&clip_dev_notifier);
1015
1016         deregister_atm_ioctl(&clip_ioctl_ops);
1017
1018         /* First, stop the idle timer, so it stops banging
1019          * on the table.
1020          */
1021         del_timer_sync(&idle_timer);
1022
1023         /* Next, purge the table, so that the device
1024          * unregister loop below does not hang due to
1025          * device references remaining in the table.
1026          */
1027         neigh_ifdown(&clip_tbl, NULL);
1028
1029         dev = clip_devs;
1030         while (dev) {
1031                 next = PRIV(dev)->next;
1032                 unregister_netdev(dev);
1033                 free_netdev(dev);
1034                 dev = next;
1035         }
1036
1037         /* Now it is safe to fully shutdown whole table. */
1038         neigh_table_clear(&clip_tbl);
1039
1040         clip_tbl_hook = NULL;
1041 }
1042
1043 module_init(atm_clip_init);
1044 module_exit(atm_clip_exit);
1045 MODULE_AUTHOR("Werner Almesberger");
1046 MODULE_DESCRIPTION("Classical/IP over ATM interface");
1047 MODULE_LICENSE("GPL");