clip.c revision aa837b5bbd92ca3791345e809d0027594faa738b 
1/* net/atm/clip.c - RFC1577 Classical IP over ATM */
2
3/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
4
5
6#include <linux/config.h>
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/proc_fs.h>
29#include <linux/seq_file.h>
30#include <linux/rcupdate.h>
31#include <linux/jhash.h>
32#include <net/route.h> /* for struct rtable and routing */
33#include <net/icmp.h> /* icmp_send */
34#include <asm/param.h> /* for HZ */
35#include <asm/byteorder.h> /* for htons etc. */
36#include <asm/system.h> /* save/restore_flags */
37#include <asm/uaccess.h>
38#include <asm/atomic.h>
39
40#include "common.h"
41#include "resources.h"
42#include "ipcommon.h"
43#include <net/atmclip.h>
44
45
46#if 0
47#define DPRINTK(format,args...) printk(format,##args)
48#else
49#define DPRINTK(format,args...)
50#endif
51
52
53static struct net_device *clip_devs;
54static struct atm_vcc *atmarpd;
55static struct neigh_table clip_tbl;
56static struct timer_list idle_timer;
57static int start_timer = 1;
58
59
60static int to_atmarpd(enum atmarp_ctrl_type type,int itf,unsigned long ip)
61{
62	struct sock *sk;
63	struct atmarp_ctrl *ctrl;
64	struct sk_buff *skb;
65
66	DPRINTK("to_atmarpd(%d)\n",type);
67	if (!atmarpd) return -EUNATCH;
68	skb = alloc_skb(sizeof(struct atmarp_ctrl),GFP_ATOMIC);
69	if (!skb) return -ENOMEM;
70	ctrl = (struct atmarp_ctrl *) skb_put(skb,sizeof(struct atmarp_ctrl));
71	ctrl->type = type;
72	ctrl->itf_num = itf;
73	ctrl->ip = ip;
74	atm_force_charge(atmarpd,skb->truesize);
75
76	sk = sk_atm(atmarpd);
77	skb_queue_tail(&sk->sk_receive_queue, skb);
78	sk->sk_data_ready(sk, skb->len);
79	return 0;
80}
81
82
83static void link_vcc(struct clip_vcc *clip_vcc,struct atmarp_entry *entry)
84{
85	DPRINTK("link_vcc %p to entry %p (neigh %p)\n",clip_vcc,entry,
86	    entry->neigh);
87	clip_vcc->entry = entry;
88	clip_vcc->xoff = 0; /* @@@ may overrun buffer by one packet */
89	clip_vcc->next = entry->vccs;
90	entry->vccs = clip_vcc;
91	entry->neigh->used = jiffies;
92}
93
94
95static void unlink_clip_vcc(struct clip_vcc *clip_vcc)
96{
97	struct atmarp_entry *entry = clip_vcc->entry;
98	struct clip_vcc **walk;
99
100	if (!entry) {
101		printk(KERN_CRIT "!clip_vcc->entry (clip_vcc %p)\n",clip_vcc);
102		return;
103	}
104	spin_lock_bh(&entry->neigh->dev->xmit_lock);	/* block clip_start_xmit() */
105	entry->neigh->used = jiffies;
106	for (walk = &entry->vccs; *walk; walk = &(*walk)->next)
107		if (*walk == clip_vcc) {
108			int error;
109
110			*walk = clip_vcc->next; /* atomic */
111			clip_vcc->entry = NULL;
112			if (clip_vcc->xoff)
113				netif_wake_queue(entry->neigh->dev);
114			if (entry->vccs)
115				goto out;
116			entry->expires = jiffies-1;
117				/* force resolution or expiration */
118			error = neigh_update(entry->neigh, NULL, NUD_NONE,
119					     NEIGH_UPDATE_F_ADMIN);
120			if (error)
121				printk(KERN_CRIT "unlink_clip_vcc: "
122				    "neigh_update failed with %d\n",error);
123			goto out;
124		}
125	printk(KERN_CRIT "ATMARP: unlink_clip_vcc failed (entry %p, vcc "
126	  "0x%p)\n",entry,clip_vcc);
127out:
128	spin_unlock_bh(&entry->neigh->dev->xmit_lock);
129}
130
131/* The neighbour entry n->lock is held. */
132static int neigh_check_cb(struct neighbour *n)
133{
134	struct atmarp_entry *entry = NEIGH2ENTRY(n);
135	struct clip_vcc *cv;
136
137	for (cv = entry->vccs; cv; cv = cv->next) {
138		unsigned long exp = cv->last_use + cv->idle_timeout;
139
140		if (cv->idle_timeout && time_after(jiffies, exp)) {
141			DPRINTK("releasing vcc %p->%p of entry %p\n",
142				cv, cv->vcc, entry);
143			vcc_release_async(cv->vcc, -ETIMEDOUT);
144		}
145	}
146
147	if (entry->vccs || time_before(jiffies, entry->expires))
148		return 0;
149
150	if (atomic_read(&n->refcnt) > 1) {
151		struct sk_buff *skb;
152
153		DPRINTK("destruction postponed with ref %d\n",
154			atomic_read(&n->refcnt));
155
156		while ((skb = skb_dequeue(&n->arp_queue)) != NULL)
157			dev_kfree_skb(skb);
158
159		return 0;
160	}
161
162	DPRINTK("expired neigh %p\n",n);
163	return 1;
164}
165
166static void idle_timer_check(unsigned long dummy)
167{
168	write_lock(&clip_tbl.lock);
169	__neigh_for_each_release(&clip_tbl, neigh_check_cb);
170	mod_timer(&idle_timer, jiffies+CLIP_CHECK_INTERVAL*HZ);
171	write_unlock(&clip_tbl.lock);
172}
173
174static int clip_arp_rcv(struct sk_buff *skb)
175{
176	struct atm_vcc *vcc;
177
178	DPRINTK("clip_arp_rcv\n");
179	vcc = ATM_SKB(skb)->vcc;
180	if (!vcc || !atm_charge(vcc,skb->truesize)) {
181		dev_kfree_skb_any(skb);
182		return 0;
183	}
184	DPRINTK("pushing to %p\n",vcc);
185	DPRINTK("using %p\n",CLIP_VCC(vcc)->old_push);
186	CLIP_VCC(vcc)->old_push(vcc,skb);
187	return 0;
188}
189
190static const unsigned char llc_oui[] = {
191	0xaa,	/* DSAP: non-ISO */
192	0xaa,	/* SSAP: non-ISO */
193	0x03,	/* Ctrl: Unnumbered Information Command PDU */
194	0x00,	/* OUI: EtherType */
195	0x00,
196	0x00 };
197
198static void clip_push(struct atm_vcc *vcc,struct sk_buff *skb)
199{
200	struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
201
202	DPRINTK("clip push\n");
203	if (!skb) {
204		DPRINTK("removing VCC %p\n",clip_vcc);
205		if (clip_vcc->entry) unlink_clip_vcc(clip_vcc);
206		clip_vcc->old_push(vcc,NULL); /* pass on the bad news */
207		kfree(clip_vcc);
208		return;
209	}
210	atm_return(vcc,skb->truesize);
211	skb->dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : clip_devs;
212		/* clip_vcc->entry == NULL if we don't have an IP address yet */
213	if (!skb->dev) {
214		dev_kfree_skb_any(skb);
215		return;
216	}
217	ATM_SKB(skb)->vcc = vcc;
218	skb->mac.raw = skb->data;
219	if (!clip_vcc->encap || skb->len < RFC1483LLC_LEN || memcmp(skb->data,
220	    llc_oui,sizeof(llc_oui))) skb->protocol = htons(ETH_P_IP);
221	else {
222		skb->protocol = ((u16 *) 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/*
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
244
245static void clip_pop(struct atm_vcc *vcc,struct sk_buff *skb)
246{
247	struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
248	struct net_device *dev = skb->dev;
249	int old;
250	unsigned long flags;
251
252	DPRINTK("clip_pop(vcc %p)\n",vcc);
253	clip_vcc->old_pop(vcc,skb);
254	/* skb->dev == NULL in outbound ARP packets */
255	if (!dev) 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) netif_wake_queue(dev);
260	}
261	spin_unlock_irqrestore(&PRIV(dev)->xoff_lock,flags);
262}
263
264
265static void clip_neigh_destroy(struct neighbour *neigh)
266{
267	DPRINTK("clip_neigh_destroy (neigh %p)\n",neigh);
268	if (NEIGH2ENTRY(neigh)->vccs)
269		printk(KERN_CRIT "clip_neigh_destroy: vccs != NULL !!!\n");
270	NEIGH2ENTRY(neigh)->vccs = (void *) 0xdeadbeef;
271}
272
273
274static void clip_neigh_solicit(struct neighbour *neigh,struct sk_buff *skb)
275{
276	DPRINTK("clip_neigh_solicit (neigh %p, skb %p)\n",neigh,skb);
277	to_atmarpd(act_need,PRIV(neigh->dev)->number,NEIGH2ENTRY(neigh)->ip);
278}
279
280
281static void clip_neigh_error(struct neighbour *neigh,struct sk_buff *skb)
282{
283#ifndef CONFIG_ATM_CLIP_NO_ICMP
284	icmp_send(skb,ICMP_DEST_UNREACH,ICMP_HOST_UNREACH,0);
285#endif
286	kfree_skb(skb);
287}
288
289
290static struct neigh_ops clip_neigh_ops = {
291	.family =		AF_INET,
292	.solicit =		clip_neigh_solicit,
293	.error_report =		clip_neigh_error,
294	.output =		dev_queue_xmit,
295	.connected_output =	dev_queue_xmit,
296	.hh_output =		dev_queue_xmit,
297	.queue_xmit =		dev_queue_xmit,
298};
299
300
301static int clip_constructor(struct neighbour *neigh)
302{
303	struct atmarp_entry *entry = NEIGH2ENTRY(neigh);
304	struct net_device *dev = neigh->dev;
305	struct in_device *in_dev;
306	struct neigh_parms *parms;
307
308	DPRINTK("clip_constructor (neigh %p, entry %p)\n",neigh,entry);
309	neigh->type = inet_addr_type(entry->ip);
310	if (neigh->type != RTN_UNICAST) return -EINVAL;
311
312	rcu_read_lock();
313	in_dev = __in_dev_get_rcu(dev);
314	if (!in_dev) {
315		rcu_read_unlock();
316		return -EINVAL;
317	}
318
319	parms = in_dev->arp_parms;
320	__neigh_parms_put(neigh->parms);
321	neigh->parms = neigh_parms_clone(parms);
322	rcu_read_unlock();
323
324	neigh->ops = &clip_neigh_ops;
325	neigh->output = neigh->nud_state & NUD_VALID ?
326	    neigh->ops->connected_output : neigh->ops->output;
327	entry->neigh = neigh;
328	entry->vccs = NULL;
329	entry->expires = jiffies-1;
330	return 0;
331}
332
333static u32 clip_hash(const void *pkey, const struct net_device *dev)
334{
335	return jhash_2words(*(u32 *)pkey, dev->ifindex, clip_tbl.hash_rnd);
336}
337
338static struct neigh_table clip_tbl = {
339	.family 	= AF_INET,
340	.entry_size 	= sizeof(struct neighbour)+sizeof(struct atmarp_entry),
341	.key_len 	= 4,
342	.hash 		= clip_hash,
343	.constructor 	= clip_constructor,
344	.id 		= "clip_arp_cache",
345
346	/* parameters are copied from ARP ... */
347	.parms = {
348		.tbl 			= &clip_tbl,
349		.neigh_destructor	= clip_neigh_destroy,
350		.base_reachable_time 	= 30 * HZ,
351		.retrans_time 		= 1 * HZ,
352		.gc_staletime 		= 60 * HZ,
353		.reachable_time 	= 30 * HZ,
354		.delay_probe_time 	= 5 * HZ,
355		.queue_len 		= 3,
356		.ucast_probes 		= 3,
357		.mcast_probes 		= 3,
358		.anycast_delay 		= 1 * HZ,
359		.proxy_delay 		= (8 * HZ) / 10,
360		.proxy_qlen 		= 64,
361		.locktime 		= 1 * HZ,
362	},
363	.gc_interval 	= 30 * HZ,
364	.gc_thresh1 	= 128,
365	.gc_thresh2 	= 512,
366	.gc_thresh3 	= 1024,
367};
368
369
370/* @@@ copy bh locking from arp.c -- need to bh-enable atm code before */
371
372/*
373 * We play with the resolve flag: 0 and 1 have the usual meaning, but -1 means
374 * to allocate the neighbour entry but not to ask atmarpd for resolution. Also,
375 * don't increment the usage count. This is used to create entries in
376 * clip_setentry.
377 */
378
379
380static int clip_encap(struct atm_vcc *vcc,int mode)
381{
382	CLIP_VCC(vcc)->encap = mode;
383	return 0;
384}
385
386
387static int clip_start_xmit(struct sk_buff *skb,struct net_device *dev)
388{
389	struct clip_priv *clip_priv = PRIV(dev);
390	struct atmarp_entry *entry;
391	struct atm_vcc *vcc;
392	int old;
393	unsigned long flags;
394
395	DPRINTK("clip_start_xmit (skb %p)\n",skb);
396	if (!skb->dst) {
397		printk(KERN_ERR "clip_start_xmit: skb->dst == NULL\n");
398		dev_kfree_skb(skb);
399		clip_priv->stats.tx_dropped++;
400		return 0;
401	}
402	if (!skb->dst->neighbour) {
403#if 0
404		skb->dst->neighbour = clip_find_neighbour(skb->dst,1);
405		if (!skb->dst->neighbour) {
406			dev_kfree_skb(skb); /* lost that one */
407			clip_priv->stats.tx_dropped++;
408			return 0;
409		}
410#endif
411		printk(KERN_ERR "clip_start_xmit: NO NEIGHBOUR !\n");
412		dev_kfree_skb(skb);
413		clip_priv->stats.tx_dropped++;
414		return 0;
415	}
416	entry = NEIGH2ENTRY(skb->dst->neighbour);
417	if (!entry->vccs) {
418		if (time_after(jiffies, entry->expires)) {
419			/* should be resolved */
420			entry->expires = jiffies+ATMARP_RETRY_DELAY*HZ;
421			to_atmarpd(act_need,PRIV(dev)->number,entry->ip);
422		}
423		if (entry->neigh->arp_queue.qlen < ATMARP_MAX_UNRES_PACKETS)
424			skb_queue_tail(&entry->neigh->arp_queue,skb);
425		else {
426			dev_kfree_skb(skb);
427			clip_priv->stats.tx_dropped++;
428		}
429		return 0;
430	}
431	DPRINTK("neigh %p, vccs %p\n",entry,entry->vccs);
432	ATM_SKB(skb)->vcc = vcc = entry->vccs->vcc;
433	DPRINTK("using neighbour %p, vcc %p\n",skb->dst->neighbour,vcc);
434	if (entry->vccs->encap) {
435		void *here;
436
437		here = skb_push(skb,RFC1483LLC_LEN);
438		memcpy(here,llc_oui,sizeof(llc_oui));
439		((u16 *) here)[3] = skb->protocol;
440	}
441	atomic_add(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);
442	ATM_SKB(skb)->atm_options = vcc->atm_options;
443	entry->vccs->last_use = jiffies;
444	DPRINTK("atm_skb(%p)->vcc(%p)->dev(%p)\n",skb,vcc,vcc->dev);
445	old = xchg(&entry->vccs->xoff,1); /* assume XOFF ... */
446	if (old) {
447		printk(KERN_WARNING "clip_start_xmit: XOFF->XOFF transition\n");
448		return 0;
449	}
450	clip_priv->stats.tx_packets++;
451	clip_priv->stats.tx_bytes += skb->len;
452	(void) vcc->send(vcc,skb);
453	if (atm_may_send(vcc,0)) {
454		entry->vccs->xoff = 0;
455		return 0;
456	}
457	spin_lock_irqsave(&clip_priv->xoff_lock,flags);
458	netif_stop_queue(dev); /* XOFF -> throttle immediately */
459	barrier();
460	if (!entry->vccs->xoff)
461		netif_start_queue(dev);
462		/* Oh, we just raced with clip_pop. netif_start_queue should be
463		   good enough, because nothing should really be asleep because
464		   of the brief netif_stop_queue. If this isn't true or if it
465		   changes, use netif_wake_queue instead. */
466	spin_unlock_irqrestore(&clip_priv->xoff_lock,flags);
467	return 0;
468}
469
470
471static struct net_device_stats *clip_get_stats(struct net_device *dev)
472{
473	return &PRIV(dev)->stats;
474}
475
476
477static int clip_mkip(struct atm_vcc *vcc,int timeout)
478{
479	struct clip_vcc *clip_vcc;
480	struct sk_buff_head copy;
481	struct sk_buff *skb;
482
483	if (!vcc->push) return -EBADFD;
484	clip_vcc = kmalloc(sizeof(struct clip_vcc),GFP_KERNEL);
485	if (!clip_vcc) return -ENOMEM;
486	DPRINTK("mkip clip_vcc %p vcc %p\n",clip_vcc,vcc);
487	clip_vcc->vcc = vcc;
488	vcc->user_back = clip_vcc;
489	set_bit(ATM_VF_IS_CLIP, &vcc->flags);
490	clip_vcc->entry = NULL;
491	clip_vcc->xoff = 0;
492	clip_vcc->encap = 1;
493	clip_vcc->last_use = jiffies;
494	clip_vcc->idle_timeout = timeout*HZ;
495	clip_vcc->old_push = vcc->push;
496	clip_vcc->old_pop = vcc->pop;
497	vcc->push = clip_push;
498	vcc->pop = clip_pop;
499	skb_queue_head_init(&copy);
500	skb_migrate(&sk_atm(vcc)->sk_receive_queue, &copy);
501	/* re-process everything received between connection setup and MKIP */
502	while ((skb = skb_dequeue(&copy)) != NULL)
503		if (!clip_devs) {
504			atm_return(vcc,skb->truesize);
505			kfree_skb(skb);
506		}
507		else {
508			unsigned int len = skb->len;
509
510			clip_push(vcc,skb);
511			PRIV(skb->dev)->stats.rx_packets--;
512			PRIV(skb->dev)->stats.rx_bytes -= len;
513		}
514	return 0;
515}
516
517
518static int clip_setentry(struct atm_vcc *vcc,u32 ip)
519{
520	struct neighbour *neigh;
521	struct atmarp_entry *entry;
522	int error;
523	struct clip_vcc *clip_vcc;
524	struct flowi fl = { .nl_u = { .ip4_u = { .daddr = ip, .tos = 1 } } };
525	struct rtable *rt;
526
527	if (vcc->push != clip_push) {
528		printk(KERN_WARNING "clip_setentry: non-CLIP VCC\n");
529		return -EBADF;
530	}
531	clip_vcc = CLIP_VCC(vcc);
532	if (!ip) {
533		if (!clip_vcc->entry) {
534			printk(KERN_ERR "hiding hidden ATMARP entry\n");
535			return 0;
536		}
537		DPRINTK("setentry: remove\n");
538		unlink_clip_vcc(clip_vcc);
539		return 0;
540	}
541	error = ip_route_output_key(&rt,&fl);
542	if (error) return error;
543	neigh = __neigh_lookup(&clip_tbl,&ip,rt->u.dst.dev,1);
544	ip_rt_put(rt);
545	if (!neigh)
546		return -ENOMEM;
547	entry = NEIGH2ENTRY(neigh);
548	if (entry != clip_vcc->entry) {
549		if (!clip_vcc->entry) DPRINTK("setentry: add\n");
550		else {
551			DPRINTK("setentry: update\n");
552			unlink_clip_vcc(clip_vcc);
553		}
554		link_vcc(clip_vcc,entry);
555	}
556	error = neigh_update(neigh, llc_oui, NUD_PERMANENT,
557			     NEIGH_UPDATE_F_OVERRIDE|NEIGH_UPDATE_F_ADMIN);
558	neigh_release(neigh);
559	return error;
560}
561
562
563static void clip_setup(struct net_device *dev)
564{
565	dev->hard_start_xmit = clip_start_xmit;
566	/* sg_xmit ... */
567	dev->get_stats = clip_get_stats;
568	dev->type = ARPHRD_ATM;
569	dev->hard_header_len = RFC1483LLC_LEN;
570	dev->mtu = RFC1626_MTU;
571	dev->tx_queue_len = 100; /* "normal" queue (packets) */
572	    /* When using a "real" qdisc, the qdisc determines the queue */
573	    /* length. tx_queue_len is only used for the default case, */
574	    /* without any more elaborate queuing. 100 is a reasonable */
575	    /* compromise between decent burst-tolerance and protection */
576	    /* against memory hogs. */
577}
578
579
580static int clip_create(int number)
581{
582	struct net_device *dev;
583	struct clip_priv *clip_priv;
584	int error;
585
586	if (number != -1) {
587		for (dev = clip_devs; dev; dev = PRIV(dev)->next)
588			if (PRIV(dev)->number == number) return -EEXIST;
589	}
590	else {
591		number = 0;
592		for (dev = clip_devs; dev; dev = PRIV(dev)->next)
593			if (PRIV(dev)->number >= number)
594				number = PRIV(dev)->number+1;
595	}
596	dev = alloc_netdev(sizeof(struct clip_priv), "", clip_setup);
597	if (!dev)
598		return -ENOMEM;
599	clip_priv = PRIV(dev);
600	sprintf(dev->name,"atm%d",number);
601	spin_lock_init(&clip_priv->xoff_lock);
602	clip_priv->number = number;
603	error = register_netdev(dev);
604	if (error) {
605		free_netdev(dev);
606		return error;
607	}
608	clip_priv->next = clip_devs;
609	clip_devs = dev;
610	DPRINTK("registered (net:%s)\n",dev->name);
611	return number;
612}
613
614
615static int clip_device_event(struct notifier_block *this,unsigned long event,
616    void *dev)
617{
618	/* ignore non-CLIP devices */
619	if (((struct net_device *) dev)->type != ARPHRD_ATM ||
620	    ((struct net_device *) dev)->hard_start_xmit != clip_start_xmit)
621		return NOTIFY_DONE;
622	switch (event) {
623		case NETDEV_UP:
624			DPRINTK("clip_device_event NETDEV_UP\n");
625			(void) to_atmarpd(act_up,PRIV(dev)->number,0);
626			break;
627		case NETDEV_GOING_DOWN:
628			DPRINTK("clip_device_event NETDEV_DOWN\n");
629			(void) to_atmarpd(act_down,PRIV(dev)->number,0);
630			break;
631		case NETDEV_CHANGE:
632		case NETDEV_CHANGEMTU:
633			DPRINTK("clip_device_event NETDEV_CHANGE*\n");
634			(void) to_atmarpd(act_change,PRIV(dev)->number,0);
635			break;
636		case NETDEV_REBOOT:
637		case NETDEV_REGISTER:
638		case NETDEV_DOWN:
639			DPRINTK("clip_device_event %ld\n",event);
640			/* ignore */
641			break;
642		default:
643			printk(KERN_WARNING "clip_device_event: unknown event "
644			    "%ld\n",event);
645			break;
646	}
647	return NOTIFY_DONE;
648}
649
650
651static int clip_inet_event(struct notifier_block *this,unsigned long event,
652    void *ifa)
653{
654	struct in_device *in_dev;
655
656	in_dev = ((struct in_ifaddr *) ifa)->ifa_dev;
657	if (!in_dev || !in_dev->dev) {
658		printk(KERN_WARNING "clip_inet_event: no device\n");
659		return NOTIFY_DONE;
660	}
661	/*
662	 * Transitions are of the down-change-up type, so it's sufficient to
663	 * handle the change on up.
664	 */
665	if (event != NETDEV_UP) return NOTIFY_DONE;
666	return clip_device_event(this,NETDEV_CHANGE,in_dev->dev);
667}
668
669
670static struct notifier_block clip_dev_notifier = {
671	clip_device_event,
672	NULL,
673	0
674};
675
676
677
678static struct notifier_block clip_inet_notifier = {
679	clip_inet_event,
680	NULL,
681	0
682};
683
684
685
686static void atmarpd_close(struct atm_vcc *vcc)
687{
688	DPRINTK("atmarpd_close\n");
689	atmarpd = NULL; /* assumed to be atomic */
690	barrier();
691	unregister_inetaddr_notifier(&clip_inet_notifier);
692	unregister_netdevice_notifier(&clip_dev_notifier);
693	if (skb_peek(&sk_atm(vcc)->sk_receive_queue))
694		printk(KERN_ERR "atmarpd_close: closing with requests "
695		    "pending\n");
696	skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
697	DPRINTK("(done)\n");
698	module_put(THIS_MODULE);
699}
700
701
702static struct atmdev_ops atmarpd_dev_ops = {
703	.close = atmarpd_close
704};
705
706
707static struct atm_dev atmarpd_dev = {
708	.ops =			&atmarpd_dev_ops,
709	.type =			"arpd",
710	.number = 		999,
711	.lock =			SPIN_LOCK_UNLOCKED
712};
713
714
715static int atm_init_atmarp(struct atm_vcc *vcc)
716{
717	if (atmarpd) return -EADDRINUSE;
718	if (start_timer) {
719		start_timer = 0;
720		init_timer(&idle_timer);
721		idle_timer.expires = jiffies+CLIP_CHECK_INTERVAL*HZ;
722		idle_timer.function = idle_timer_check;
723		add_timer(&idle_timer);
724	}
725	atmarpd = vcc;
726	set_bit(ATM_VF_META,&vcc->flags);
727	set_bit(ATM_VF_READY,&vcc->flags);
728	    /* allow replies and avoid getting closed if signaling dies */
729	vcc->dev = &atmarpd_dev;
730	vcc_insert_socket(sk_atm(vcc));
731	vcc->push = NULL;
732	vcc->pop = NULL; /* crash */
733	vcc->push_oam = NULL; /* crash */
734	if (register_netdevice_notifier(&clip_dev_notifier))
735		printk(KERN_ERR "register_netdevice_notifier failed\n");
736	if (register_inetaddr_notifier(&clip_inet_notifier))
737		printk(KERN_ERR "register_inetaddr_notifier failed\n");
738	return 0;
739}
740
741static 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, arg);
775			break;
776		case ATMARP_ENCAP:
777			err = clip_encap(vcc, arg);
778			break;
779	}
780	return err;
781}
782
783static struct atm_ioctl clip_ioctl_ops = {
784	.owner 	= THIS_MODULE,
785	.ioctl	= clip_ioctl,
786};
787
788#ifdef CONFIG_PROC_FS
789
790static 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
821static 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) ||
832	       clip_vcc->encap);
833
834	if (clip_vcc == SEQ_NO_VCC_TOKEN)
835		exp = entry->neigh->used;
836	else
837		exp = clip_vcc->last_use;
838
839	exp = (jiffies - exp) / HZ;
840
841	seq_printf(seq, "%-6s%-4s%-4s%5ld ",
842		   dev->name,
843		   svc ? "SVC" : "PVC",
844		   llc ? "LLC" : "NULL",
845		   exp);
846
847	off = scnprintf(buf, sizeof(buf) - 1, "%d.%d.%d.%d",
848			NIPQUAD(entry->ip));
849	while (off < 16)
850		buf[off++] = ' ';
851	buf[off] = '\0';
852	seq_printf(seq, "%s", buf);
853
854	if (clip_vcc == SEQ_NO_VCC_TOKEN) {
855		if (time_before(jiffies, entry->expires))
856			seq_printf(seq, "(resolving)\n");
857		else
858			seq_printf(seq, "(expired, ref %d)\n",
859				   atomic_read(&entry->neigh->refcnt));
860	} else if (!svc) {
861		seq_printf(seq, "%d.%d.%d\n",
862			   clip_vcc->vcc->dev->number,
863			   clip_vcc->vcc->vpi,
864			   clip_vcc->vcc->vci);
865	} else {
866		svc_addr(seq, &clip_vcc->vcc->remote);
867		seq_putc(seq, '\n');
868	}
869}
870
871struct clip_seq_state {
872	/* This member must be first. */
873	struct neigh_seq_state ns;
874
875	/* Local to clip specific iteration. */
876	struct clip_vcc *vcc;
877};
878
879static struct clip_vcc *clip_seq_next_vcc(struct atmarp_entry *e,
880					  struct clip_vcc *curr)
881{
882	if (!curr) {
883		curr = e->vccs;
884		if (!curr)
885			return SEQ_NO_VCC_TOKEN;
886		return curr;
887	}
888	if (curr == SEQ_NO_VCC_TOKEN)
889		return NULL;
890
891	curr = curr->next;
892
893	return curr;
894}
895
896static void *clip_seq_vcc_walk(struct clip_seq_state *state,
897			       struct atmarp_entry *e, loff_t *pos)
898{
899	struct clip_vcc *vcc = state->vcc;
900
901	vcc = clip_seq_next_vcc(e, vcc);
902	if (vcc && pos != NULL) {
903		while (*pos) {
904			vcc = clip_seq_next_vcc(e, vcc);
905			if (!vcc)
906				break;
907			--(*pos);
908		}
909	}
910	state->vcc = vcc;
911
912	return vcc;
913}
914
915static void *clip_seq_sub_iter(struct neigh_seq_state *_state,
916			       struct neighbour *n, loff_t *pos)
917{
918	struct clip_seq_state *state = (struct clip_seq_state *) _state;
919
920	return clip_seq_vcc_walk(state, NEIGH2ENTRY(n), pos);
921}
922
923static void *clip_seq_start(struct seq_file *seq, loff_t *pos)
924{
925	return neigh_seq_start(seq, pos, &clip_tbl, NEIGH_SEQ_NEIGH_ONLY);
926}
927
928static int clip_seq_show(struct seq_file *seq, void *v)
929{
930	static char atm_arp_banner[] =
931		"IPitf TypeEncp Idle IP address      ATM address\n";
932
933	if (v == SEQ_START_TOKEN) {
934		seq_puts(seq, atm_arp_banner);
935	} else {
936		struct clip_seq_state *state = seq->private;
937		struct neighbour *n = v;
938		struct clip_vcc *vcc = state->vcc;
939
940		atmarp_info(seq, n->dev, NEIGH2ENTRY(n), vcc);
941	}
942  	return 0;
943}
944
945static struct seq_operations arp_seq_ops = {
946	.start	= clip_seq_start,
947	.next	= neigh_seq_next,
948	.stop	= neigh_seq_stop,
949	.show	= clip_seq_show,
950};
951
952static int arp_seq_open(struct inode *inode, struct file *file)
953{
954	struct clip_seq_state *state;
955	struct seq_file *seq;
956	int rc = -EAGAIN;
957
958	state = kmalloc(sizeof(*state), GFP_KERNEL);
959	if (!state) {
960		rc = -ENOMEM;
961		goto out_kfree;
962	}
963	memset(state, 0, sizeof(*state));
964	state->ns.neigh_sub_iter = clip_seq_sub_iter;
965
966	rc = seq_open(file, &arp_seq_ops);
967	if (rc)
968		goto out_kfree;
969
970	seq = file->private_data;
971	seq->private = state;
972out:
973	return rc;
974
975out_kfree:
976	kfree(state);
977	goto out;
978}
979
980static struct file_operations arp_seq_fops = {
981	.open		= arp_seq_open,
982	.read		= seq_read,
983	.llseek		= seq_lseek,
984	.release	= seq_release_private,
985	.owner		= THIS_MODULE
986};
987#endif
988
989static int __init atm_clip_init(void)
990{
991	neigh_table_init(&clip_tbl);
992
993	clip_tbl_hook = &clip_tbl;
994	register_atm_ioctl(&clip_ioctl_ops);
995
996#ifdef CONFIG_PROC_FS
997{
998	struct proc_dir_entry *p;
999
1000	p = create_proc_entry("arp", S_IRUGO, atm_proc_root);
1001	if (p)
1002		p->proc_fops = &arp_seq_fops;
1003}
1004#endif
1005
1006	return 0;
1007}
1008
1009static void __exit atm_clip_exit(void)
1010{
1011	struct net_device *dev, *next;
1012
1013	remove_proc_entry("arp", atm_proc_root);
1014
1015	deregister_atm_ioctl(&clip_ioctl_ops);
1016
1017	/* First, stop the idle timer, so it stops banging
1018	 * on the table.
1019	 */
1020	if (start_timer == 0)
1021		del_timer(&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
1043module_init(atm_clip_init);
1044module_exit(atm_clip_exit);
1045
1046MODULE_LICENSE("GPL");
1047