ia64/linux-2.6.18-xen.hg

view net/appletalk/aarp.c @ 673:3161879fdf22

[IA64] xencomm: support XENMEM_add_to_physmap and XENMEM_remove_from_phsymap

support XENMEM_add_to_physmap and XENMEM_remove_from_phsymap.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
author Isaku Yamahata <yamahata@valinux.co.jp>
date Tue Sep 16 21:26:15 2008 +0900 (2008-09-16)
parents 831230e53067
children
line source
1 /*
2 * AARP: An implementation of the AppleTalk AARP protocol for
3 * Ethernet 'ELAP'.
4 *
5 * Alan Cox <Alan.Cox@linux.org>
6 *
7 * This doesn't fit cleanly with the IP arp. Potentially we can use
8 * the generic neighbour discovery code to clean this up.
9 *
10 * FIXME:
11 * We ought to handle the retransmits with a single list and a
12 * separate fast timer for when it is needed.
13 * Use neighbour discovery code.
14 * Token Ring Support.
15 *
16 * This program is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU General Public License
18 * as published by the Free Software Foundation; either version
19 * 2 of the License, or (at your option) any later version.
20 *
21 *
22 * References:
23 * Inside AppleTalk (2nd Ed).
24 * Fixes:
25 * Jaume Grau - flush caches on AARP_PROBE
26 * Rob Newberry - Added proxy AARP and AARP proc fs,
27 * moved probing from DDP module.
28 * Arnaldo C. Melo - don't mangle rx packets
29 *
30 */
32 #include <linux/if_arp.h>
33 #include <net/sock.h>
34 #include <net/datalink.h>
35 #include <net/psnap.h>
36 #include <linux/atalk.h>
37 #include <linux/delay.h>
38 #include <linux/init.h>
39 #include <linux/proc_fs.h>
40 #include <linux/seq_file.h>
42 int sysctl_aarp_expiry_time = AARP_EXPIRY_TIME;
43 int sysctl_aarp_tick_time = AARP_TICK_TIME;
44 int sysctl_aarp_retransmit_limit = AARP_RETRANSMIT_LIMIT;
45 int sysctl_aarp_resolve_time = AARP_RESOLVE_TIME;
47 /* Lists of aarp entries */
48 /**
49 * struct aarp_entry - AARP entry
50 * @last_sent - Last time we xmitted the aarp request
51 * @packet_queue - Queue of frames wait for resolution
52 * @status - Used for proxy AARP
53 * expires_at - Entry expiry time
54 * target_addr - DDP Address
55 * dev - Device to use
56 * hwaddr - Physical i/f address of target/router
57 * xmit_count - When this hits 10 we give up
58 * next - Next entry in chain
59 */
60 struct aarp_entry {
61 /* These first two are only used for unresolved entries */
62 unsigned long last_sent;
63 struct sk_buff_head packet_queue;
64 int status;
65 unsigned long expires_at;
66 struct atalk_addr target_addr;
67 struct net_device *dev;
68 char hwaddr[6];
69 unsigned short xmit_count;
70 struct aarp_entry *next;
71 };
73 /* Hashed list of resolved, unresolved and proxy entries */
74 static struct aarp_entry *resolved[AARP_HASH_SIZE];
75 static struct aarp_entry *unresolved[AARP_HASH_SIZE];
76 static struct aarp_entry *proxies[AARP_HASH_SIZE];
77 static int unresolved_count;
79 /* One lock protects it all. */
80 static DEFINE_RWLOCK(aarp_lock);
82 /* Used to walk the list and purge/kick entries. */
83 static struct timer_list aarp_timer;
85 /*
86 * Delete an aarp queue
87 *
88 * Must run under aarp_lock.
89 */
90 static void __aarp_expire(struct aarp_entry *a)
91 {
92 skb_queue_purge(&a->packet_queue);
93 kfree(a);
94 }
96 /*
97 * Send an aarp queue entry request
98 *
99 * Must run under aarp_lock.
100 */
101 static void __aarp_send_query(struct aarp_entry *a)
102 {
103 static unsigned char aarp_eth_multicast[ETH_ALEN] =
104 { 0x09, 0x00, 0x07, 0xFF, 0xFF, 0xFF };
105 struct net_device *dev = a->dev;
106 struct elapaarp *eah;
107 int len = dev->hard_header_len + sizeof(*eah) + aarp_dl->header_length;
108 struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC);
109 struct atalk_addr *sat = atalk_find_dev_addr(dev);
111 if (!skb)
112 return;
114 if (!sat) {
115 kfree_skb(skb);
116 return;
117 }
119 /* Set up the buffer */
120 skb_reserve(skb, dev->hard_header_len + aarp_dl->header_length);
121 skb->nh.raw = skb->h.raw = skb_put(skb, sizeof(*eah));
122 skb->protocol = htons(ETH_P_ATALK);
123 skb->dev = dev;
124 eah = aarp_hdr(skb);
126 /* Set up the ARP */
127 eah->hw_type = htons(AARP_HW_TYPE_ETHERNET);
128 eah->pa_type = htons(ETH_P_ATALK);
129 eah->hw_len = ETH_ALEN;
130 eah->pa_len = AARP_PA_ALEN;
131 eah->function = htons(AARP_REQUEST);
133 memcpy(eah->hw_src, dev->dev_addr, ETH_ALEN);
135 eah->pa_src_zero = 0;
136 eah->pa_src_net = sat->s_net;
137 eah->pa_src_node = sat->s_node;
139 memset(eah->hw_dst, '\0', ETH_ALEN);
141 eah->pa_dst_zero = 0;
142 eah->pa_dst_net = a->target_addr.s_net;
143 eah->pa_dst_node = a->target_addr.s_node;
145 /* Send it */
146 aarp_dl->request(aarp_dl, skb, aarp_eth_multicast);
147 /* Update the sending count */
148 a->xmit_count++;
149 a->last_sent = jiffies;
150 }
152 /* This runs under aarp_lock and in softint context, so only atomic memory
153 * allocations can be used. */
154 static void aarp_send_reply(struct net_device *dev, struct atalk_addr *us,
155 struct atalk_addr *them, unsigned char *sha)
156 {
157 struct elapaarp *eah;
158 int len = dev->hard_header_len + sizeof(*eah) + aarp_dl->header_length;
159 struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC);
161 if (!skb)
162 return;
164 /* Set up the buffer */
165 skb_reserve(skb, dev->hard_header_len + aarp_dl->header_length);
166 skb->nh.raw = skb->h.raw = skb_put(skb, sizeof(*eah));
167 skb->protocol = htons(ETH_P_ATALK);
168 skb->dev = dev;
169 eah = aarp_hdr(skb);
171 /* Set up the ARP */
172 eah->hw_type = htons(AARP_HW_TYPE_ETHERNET);
173 eah->pa_type = htons(ETH_P_ATALK);
174 eah->hw_len = ETH_ALEN;
175 eah->pa_len = AARP_PA_ALEN;
176 eah->function = htons(AARP_REPLY);
178 memcpy(eah->hw_src, dev->dev_addr, ETH_ALEN);
180 eah->pa_src_zero = 0;
181 eah->pa_src_net = us->s_net;
182 eah->pa_src_node = us->s_node;
184 if (!sha)
185 memset(eah->hw_dst, '\0', ETH_ALEN);
186 else
187 memcpy(eah->hw_dst, sha, ETH_ALEN);
189 eah->pa_dst_zero = 0;
190 eah->pa_dst_net = them->s_net;
191 eah->pa_dst_node = them->s_node;
193 /* Send it */
194 aarp_dl->request(aarp_dl, skb, sha);
195 }
197 /*
198 * Send probe frames. Called from aarp_probe_network and
199 * aarp_proxy_probe_network.
200 */
202 static void aarp_send_probe(struct net_device *dev, struct atalk_addr *us)
203 {
204 struct elapaarp *eah;
205 int len = dev->hard_header_len + sizeof(*eah) + aarp_dl->header_length;
206 struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC);
207 static unsigned char aarp_eth_multicast[ETH_ALEN] =
208 { 0x09, 0x00, 0x07, 0xFF, 0xFF, 0xFF };
210 if (!skb)
211 return;
213 /* Set up the buffer */
214 skb_reserve(skb, dev->hard_header_len + aarp_dl->header_length);
215 skb->nh.raw = skb->h.raw = skb_put(skb, sizeof(*eah));
216 skb->protocol = htons(ETH_P_ATALK);
217 skb->dev = dev;
218 eah = aarp_hdr(skb);
220 /* Set up the ARP */
221 eah->hw_type = htons(AARP_HW_TYPE_ETHERNET);
222 eah->pa_type = htons(ETH_P_ATALK);
223 eah->hw_len = ETH_ALEN;
224 eah->pa_len = AARP_PA_ALEN;
225 eah->function = htons(AARP_PROBE);
227 memcpy(eah->hw_src, dev->dev_addr, ETH_ALEN);
229 eah->pa_src_zero = 0;
230 eah->pa_src_net = us->s_net;
231 eah->pa_src_node = us->s_node;
233 memset(eah->hw_dst, '\0', ETH_ALEN);
235 eah->pa_dst_zero = 0;
236 eah->pa_dst_net = us->s_net;
237 eah->pa_dst_node = us->s_node;
239 /* Send it */
240 aarp_dl->request(aarp_dl, skb, aarp_eth_multicast);
241 }
243 /*
244 * Handle an aarp timer expire
245 *
246 * Must run under the aarp_lock.
247 */
249 static void __aarp_expire_timer(struct aarp_entry **n)
250 {
251 struct aarp_entry *t;
253 while (*n)
254 /* Expired ? */
255 if (time_after(jiffies, (*n)->expires_at)) {
256 t = *n;
257 *n = (*n)->next;
258 __aarp_expire(t);
259 } else
260 n = &((*n)->next);
261 }
263 /*
264 * Kick all pending requests 5 times a second.
265 *
266 * Must run under the aarp_lock.
267 */
268 static void __aarp_kick(struct aarp_entry **n)
269 {
270 struct aarp_entry *t;
272 while (*n)
273 /* Expired: if this will be the 11th tx, we delete instead. */
274 if ((*n)->xmit_count >= sysctl_aarp_retransmit_limit) {
275 t = *n;
276 *n = (*n)->next;
277 __aarp_expire(t);
278 } else {
279 __aarp_send_query(*n);
280 n = &((*n)->next);
281 }
282 }
284 /*
285 * A device has gone down. Take all entries referring to the device
286 * and remove them.
287 *
288 * Must run under the aarp_lock.
289 */
290 static void __aarp_expire_device(struct aarp_entry **n, struct net_device *dev)
291 {
292 struct aarp_entry *t;
294 while (*n)
295 if ((*n)->dev == dev) {
296 t = *n;
297 *n = (*n)->next;
298 __aarp_expire(t);
299 } else
300 n = &((*n)->next);
301 }
303 /* Handle the timer event */
304 static void aarp_expire_timeout(unsigned long unused)
305 {
306 int ct;
308 write_lock_bh(&aarp_lock);
310 for (ct = 0; ct < AARP_HASH_SIZE; ct++) {
311 __aarp_expire_timer(&resolved[ct]);
312 __aarp_kick(&unresolved[ct]);
313 __aarp_expire_timer(&unresolved[ct]);
314 __aarp_expire_timer(&proxies[ct]);
315 }
317 write_unlock_bh(&aarp_lock);
318 mod_timer(&aarp_timer, jiffies +
319 (unresolved_count ? sysctl_aarp_tick_time :
320 sysctl_aarp_expiry_time));
321 }
323 /* Network device notifier chain handler. */
324 static int aarp_device_event(struct notifier_block *this, unsigned long event,
325 void *ptr)
326 {
327 int ct;
329 if (event == NETDEV_DOWN) {
330 write_lock_bh(&aarp_lock);
332 for (ct = 0; ct < AARP_HASH_SIZE; ct++) {
333 __aarp_expire_device(&resolved[ct], ptr);
334 __aarp_expire_device(&unresolved[ct], ptr);
335 __aarp_expire_device(&proxies[ct], ptr);
336 }
338 write_unlock_bh(&aarp_lock);
339 }
340 return NOTIFY_DONE;
341 }
343 /* Expire all entries in a hash chain */
344 static void __aarp_expire_all(struct aarp_entry **n)
345 {
346 struct aarp_entry *t;
348 while (*n) {
349 t = *n;
350 *n = (*n)->next;
351 __aarp_expire(t);
352 }
353 }
355 /* Cleanup all hash chains -- module unloading */
356 static void aarp_purge(void)
357 {
358 int ct;
360 write_lock_bh(&aarp_lock);
361 for (ct = 0; ct < AARP_HASH_SIZE; ct++) {
362 __aarp_expire_all(&resolved[ct]);
363 __aarp_expire_all(&unresolved[ct]);
364 __aarp_expire_all(&proxies[ct]);
365 }
366 write_unlock_bh(&aarp_lock);
367 }
369 /*
370 * Create a new aarp entry. This must use GFP_ATOMIC because it
371 * runs while holding spinlocks.
372 */
373 static struct aarp_entry *aarp_alloc(void)
374 {
375 struct aarp_entry *a = kmalloc(sizeof(*a), GFP_ATOMIC);
377 if (a)
378 skb_queue_head_init(&a->packet_queue);
379 return a;
380 }
382 /*
383 * Find an entry. We might return an expired but not yet purged entry. We
384 * don't care as it will do no harm.
385 *
386 * This must run under the aarp_lock.
387 */
388 static struct aarp_entry *__aarp_find_entry(struct aarp_entry *list,
389 struct net_device *dev,
390 struct atalk_addr *sat)
391 {
392 while (list) {
393 if (list->target_addr.s_net == sat->s_net &&
394 list->target_addr.s_node == sat->s_node &&
395 list->dev == dev)
396 break;
397 list = list->next;
398 }
400 return list;
401 }
403 /* Called from the DDP code, and thus must be exported. */
404 void aarp_proxy_remove(struct net_device *dev, struct atalk_addr *sa)
405 {
406 int hash = sa->s_node % (AARP_HASH_SIZE - 1);
407 struct aarp_entry *a;
409 write_lock_bh(&aarp_lock);
411 a = __aarp_find_entry(proxies[hash], dev, sa);
412 if (a)
413 a->expires_at = jiffies - 1;
415 write_unlock_bh(&aarp_lock);
416 }
418 /* This must run under aarp_lock. */
419 static struct atalk_addr *__aarp_proxy_find(struct net_device *dev,
420 struct atalk_addr *sa)
421 {
422 int hash = sa->s_node % (AARP_HASH_SIZE - 1);
423 struct aarp_entry *a = __aarp_find_entry(proxies[hash], dev, sa);
425 return a ? sa : NULL;
426 }
428 /*
429 * Probe a Phase 1 device or a device that requires its Net:Node to
430 * be set via an ioctl.
431 */
432 static void aarp_send_probe_phase1(struct atalk_iface *iface)
433 {
434 struct ifreq atreq;
435 struct sockaddr_at *sa = (struct sockaddr_at *)&atreq.ifr_addr;
437 sa->sat_addr.s_node = iface->address.s_node;
438 sa->sat_addr.s_net = ntohs(iface->address.s_net);
440 /* We pass the Net:Node to the drivers/cards by a Device ioctl. */
441 if (!(iface->dev->do_ioctl(iface->dev, &atreq, SIOCSIFADDR))) {
442 (void)iface->dev->do_ioctl(iface->dev, &atreq, SIOCGIFADDR);
443 if (iface->address.s_net != htons(sa->sat_addr.s_net) ||
444 iface->address.s_node != sa->sat_addr.s_node)
445 iface->status |= ATIF_PROBE_FAIL;
447 iface->address.s_net = htons(sa->sat_addr.s_net);
448 iface->address.s_node = sa->sat_addr.s_node;
449 }
450 }
453 void aarp_probe_network(struct atalk_iface *atif)
454 {
455 if (atif->dev->type == ARPHRD_LOCALTLK ||
456 atif->dev->type == ARPHRD_PPP)
457 aarp_send_probe_phase1(atif);
458 else {
459 unsigned int count;
461 for (count = 0; count < AARP_RETRANSMIT_LIMIT; count++) {
462 aarp_send_probe(atif->dev, &atif->address);
464 /* Defer 1/10th */
465 msleep(100);
467 if (atif->status & ATIF_PROBE_FAIL)
468 break;
469 }
470 }
471 }
473 int aarp_proxy_probe_network(struct atalk_iface *atif, struct atalk_addr *sa)
474 {
475 int hash, retval = -EPROTONOSUPPORT;
476 struct aarp_entry *entry;
477 unsigned int count;
479 /*
480 * we don't currently support LocalTalk or PPP for proxy AARP;
481 * if someone wants to try and add it, have fun
482 */
483 if (atif->dev->type == ARPHRD_LOCALTLK ||
484 atif->dev->type == ARPHRD_PPP)
485 goto out;
487 /*
488 * create a new AARP entry with the flags set to be published --
489 * we need this one to hang around even if it's in use
490 */
491 entry = aarp_alloc();
492 retval = -ENOMEM;
493 if (!entry)
494 goto out;
496 entry->expires_at = -1;
497 entry->status = ATIF_PROBE;
498 entry->target_addr.s_node = sa->s_node;
499 entry->target_addr.s_net = sa->s_net;
500 entry->dev = atif->dev;
502 write_lock_bh(&aarp_lock);
504 hash = sa->s_node % (AARP_HASH_SIZE - 1);
505 entry->next = proxies[hash];
506 proxies[hash] = entry;
508 for (count = 0; count < AARP_RETRANSMIT_LIMIT; count++) {
509 aarp_send_probe(atif->dev, sa);
511 /* Defer 1/10th */
512 write_unlock_bh(&aarp_lock);
513 msleep(100);
514 write_lock_bh(&aarp_lock);
516 if (entry->status & ATIF_PROBE_FAIL)
517 break;
518 }
520 if (entry->status & ATIF_PROBE_FAIL) {
521 entry->expires_at = jiffies - 1; /* free the entry */
522 retval = -EADDRINUSE; /* return network full */
523 } else { /* clear the probing flag */
524 entry->status &= ~ATIF_PROBE;
525 retval = 1;
526 }
528 write_unlock_bh(&aarp_lock);
529 out:
530 return retval;
531 }
533 /* Send a DDP frame */
534 int aarp_send_ddp(struct net_device *dev, struct sk_buff *skb,
535 struct atalk_addr *sa, void *hwaddr)
536 {
537 static char ddp_eth_multicast[ETH_ALEN] =
538 { 0x09, 0x00, 0x07, 0xFF, 0xFF, 0xFF };
539 int hash;
540 struct aarp_entry *a;
542 skb->nh.raw = skb->data;
544 /* Check for LocalTalk first */
545 if (dev->type == ARPHRD_LOCALTLK) {
546 struct atalk_addr *at = atalk_find_dev_addr(dev);
547 struct ddpehdr *ddp = (struct ddpehdr *)skb->data;
548 int ft = 2;
550 /*
551 * Compressible ?
552 *
553 * IFF: src_net == dest_net == device_net
554 * (zero matches anything)
555 */
557 if ((!ddp->deh_snet || at->s_net == ddp->deh_snet) &&
558 (!ddp->deh_dnet || at->s_net == ddp->deh_dnet)) {
559 skb_pull(skb, sizeof(*ddp) - 4);
561 /*
562 * The upper two remaining bytes are the port
563 * numbers we just happen to need. Now put the
564 * length in the lower two.
565 */
566 *((__be16 *)skb->data) = htons(skb->len);
567 ft = 1;
568 }
569 /*
570 * Nice and easy. No AARP type protocols occur here so we can
571 * just shovel it out with a 3 byte LLAP header
572 */
574 skb_push(skb, 3);
575 skb->data[0] = sa->s_node;
576 skb->data[1] = at->s_node;
577 skb->data[2] = ft;
578 skb->dev = dev;
579 goto sendit;
580 }
582 /* On a PPP link we neither compress nor aarp. */
583 if (dev->type == ARPHRD_PPP) {
584 skb->protocol = htons(ETH_P_PPPTALK);
585 skb->dev = dev;
586 goto sendit;
587 }
589 /* Non ELAP we cannot do. */
590 if (dev->type != ARPHRD_ETHER)
591 return -1;
593 skb->dev = dev;
594 skb->protocol = htons(ETH_P_ATALK);
595 hash = sa->s_node % (AARP_HASH_SIZE - 1);
597 /* Do we have a resolved entry? */
598 if (sa->s_node == ATADDR_BCAST) {
599 /* Send it */
600 ddp_dl->request(ddp_dl, skb, ddp_eth_multicast);
601 goto sent;
602 }
604 write_lock_bh(&aarp_lock);
605 a = __aarp_find_entry(resolved[hash], dev, sa);
607 if (a) { /* Return 1 and fill in the address */
608 a->expires_at = jiffies + (sysctl_aarp_expiry_time * 10);
609 ddp_dl->request(ddp_dl, skb, a->hwaddr);
610 write_unlock_bh(&aarp_lock);
611 goto sent;
612 }
614 /* Do we have an unresolved entry: This is the less common path */
615 a = __aarp_find_entry(unresolved[hash], dev, sa);
616 if (a) { /* Queue onto the unresolved queue */
617 skb_queue_tail(&a->packet_queue, skb);
618 goto out_unlock;
619 }
621 /* Allocate a new entry */
622 a = aarp_alloc();
623 if (!a) {
624 /* Whoops slipped... good job it's an unreliable protocol 8) */
625 write_unlock_bh(&aarp_lock);
626 return -1;
627 }
629 /* Set up the queue */
630 skb_queue_tail(&a->packet_queue, skb);
631 a->expires_at = jiffies + sysctl_aarp_resolve_time;
632 a->dev = dev;
633 a->next = unresolved[hash];
634 a->target_addr = *sa;
635 a->xmit_count = 0;
636 unresolved[hash] = a;
637 unresolved_count++;
639 /* Send an initial request for the address */
640 __aarp_send_query(a);
642 /*
643 * Switch to fast timer if needed (That is if this is the first
644 * unresolved entry to get added)
645 */
647 if (unresolved_count == 1)
648 mod_timer(&aarp_timer, jiffies + sysctl_aarp_tick_time);
650 /* Now finally, it is safe to drop the lock. */
651 out_unlock:
652 write_unlock_bh(&aarp_lock);
654 /* Tell the ddp layer we have taken over for this frame. */
655 return 0;
657 sendit:
658 if (skb->sk)
659 skb->priority = skb->sk->sk_priority;
660 dev_queue_xmit(skb);
661 sent:
662 return 1;
663 }
665 /*
666 * An entry in the aarp unresolved queue has become resolved. Send
667 * all the frames queued under it.
668 *
669 * Must run under aarp_lock.
670 */
671 static void __aarp_resolved(struct aarp_entry **list, struct aarp_entry *a,
672 int hash)
673 {
674 struct sk_buff *skb;
676 while (*list)
677 if (*list == a) {
678 unresolved_count--;
679 *list = a->next;
681 /* Move into the resolved list */
682 a->next = resolved[hash];
683 resolved[hash] = a;
685 /* Kick frames off */
686 while ((skb = skb_dequeue(&a->packet_queue)) != NULL) {
687 a->expires_at = jiffies +
688 sysctl_aarp_expiry_time * 10;
689 ddp_dl->request(ddp_dl, skb, a->hwaddr);
690 }
691 } else
692 list = &((*list)->next);
693 }
695 /*
696 * This is called by the SNAP driver whenever we see an AARP SNAP
697 * frame. We currently only support Ethernet.
698 */
699 static int aarp_rcv(struct sk_buff *skb, struct net_device *dev,
700 struct packet_type *pt, struct net_device *orig_dev)
701 {
702 struct elapaarp *ea = aarp_hdr(skb);
703 int hash, ret = 0;
704 __u16 function;
705 struct aarp_entry *a;
706 struct atalk_addr sa, *ma, da;
707 struct atalk_iface *ifa;
709 /* We only do Ethernet SNAP AARP. */
710 if (dev->type != ARPHRD_ETHER)
711 goto out0;
713 /* Frame size ok? */
714 if (!skb_pull(skb, sizeof(*ea)))
715 goto out0;
717 function = ntohs(ea->function);
719 /* Sanity check fields. */
720 if (function < AARP_REQUEST || function > AARP_PROBE ||
721 ea->hw_len != ETH_ALEN || ea->pa_len != AARP_PA_ALEN ||
722 ea->pa_src_zero || ea->pa_dst_zero)
723 goto out0;
725 /* Looks good. */
726 hash = ea->pa_src_node % (AARP_HASH_SIZE - 1);
728 /* Build an address. */
729 sa.s_node = ea->pa_src_node;
730 sa.s_net = ea->pa_src_net;
732 /* Process the packet. Check for replies of me. */
733 ifa = atalk_find_dev(dev);
734 if (!ifa)
735 goto out1;
737 if (ifa->status & ATIF_PROBE &&
738 ifa->address.s_node == ea->pa_dst_node &&
739 ifa->address.s_net == ea->pa_dst_net) {
740 ifa->status |= ATIF_PROBE_FAIL; /* Fail the probe (in use) */
741 goto out1;
742 }
744 /* Check for replies of proxy AARP entries */
745 da.s_node = ea->pa_dst_node;
746 da.s_net = ea->pa_dst_net;
748 write_lock_bh(&aarp_lock);
749 a = __aarp_find_entry(proxies[hash], dev, &da);
751 if (a && a->status & ATIF_PROBE) {
752 a->status |= ATIF_PROBE_FAIL;
753 /*
754 * we do not respond to probe or request packets for
755 * this address while we are probing this address
756 */
757 goto unlock;
758 }
760 switch (function) {
761 case AARP_REPLY:
762 if (!unresolved_count) /* Speed up */
763 break;
765 /* Find the entry. */
766 a = __aarp_find_entry(unresolved[hash], dev, &sa);
767 if (!a || dev != a->dev)
768 break;
770 /* We can fill one in - this is good. */
771 memcpy(a->hwaddr, ea->hw_src, ETH_ALEN);
772 __aarp_resolved(&unresolved[hash], a, hash);
773 if (!unresolved_count)
774 mod_timer(&aarp_timer,
775 jiffies + sysctl_aarp_expiry_time);
776 break;
778 case AARP_REQUEST:
779 case AARP_PROBE:
781 /*
782 * If it is my address set ma to my address and reply.
783 * We can treat probe and request the same. Probe
784 * simply means we shouldn't cache the querying host,
785 * as in a probe they are proposing an address not
786 * using one.
787 *
788 * Support for proxy-AARP added. We check if the
789 * address is one of our proxies before we toss the
790 * packet out.
791 */
793 sa.s_node = ea->pa_dst_node;
794 sa.s_net = ea->pa_dst_net;
796 /* See if we have a matching proxy. */
797 ma = __aarp_proxy_find(dev, &sa);
798 if (!ma)
799 ma = &ifa->address;
800 else { /* We need to make a copy of the entry. */
801 da.s_node = sa.s_node;
802 da.s_net = da.s_net;
803 ma = &da;
804 }
806 if (function == AARP_PROBE) {
807 /*
808 * A probe implies someone trying to get an
809 * address. So as a precaution flush any
810 * entries we have for this address.
811 */
812 struct aarp_entry *a;
814 a = __aarp_find_entry(resolved[sa.s_node %
815 (AARP_HASH_SIZE - 1)],
816 skb->dev, &sa);
818 /*
819 * Make it expire next tick - that avoids us
820 * getting into a probe/flush/learn/probe/
821 * flush/learn cycle during probing of a slow
822 * to respond host addr.
823 */
824 if (a) {
825 a->expires_at = jiffies - 1;
826 mod_timer(&aarp_timer, jiffies +
827 sysctl_aarp_tick_time);
828 }
829 }
831 if (sa.s_node != ma->s_node)
832 break;
834 if (sa.s_net && ma->s_net && sa.s_net != ma->s_net)
835 break;
837 sa.s_node = ea->pa_src_node;
838 sa.s_net = ea->pa_src_net;
840 /* aarp_my_address has found the address to use for us.
841 */
842 aarp_send_reply(dev, ma, &sa, ea->hw_src);
843 break;
844 }
846 unlock:
847 write_unlock_bh(&aarp_lock);
848 out1:
849 ret = 1;
850 out0:
851 kfree_skb(skb);
852 return ret;
853 }
855 static struct notifier_block aarp_notifier = {
856 .notifier_call = aarp_device_event,
857 };
859 static unsigned char aarp_snap_id[] = { 0x00, 0x00, 0x00, 0x80, 0xF3 };
861 void __init aarp_proto_init(void)
862 {
863 aarp_dl = register_snap_client(aarp_snap_id, aarp_rcv);
864 if (!aarp_dl)
865 printk(KERN_CRIT "Unable to register AARP with SNAP.\n");
866 init_timer(&aarp_timer);
867 aarp_timer.function = aarp_expire_timeout;
868 aarp_timer.data = 0;
869 aarp_timer.expires = jiffies + sysctl_aarp_expiry_time;
870 add_timer(&aarp_timer);
871 register_netdevice_notifier(&aarp_notifier);
872 }
874 /* Remove the AARP entries associated with a device. */
875 void aarp_device_down(struct net_device *dev)
876 {
877 int ct;
879 write_lock_bh(&aarp_lock);
881 for (ct = 0; ct < AARP_HASH_SIZE; ct++) {
882 __aarp_expire_device(&resolved[ct], dev);
883 __aarp_expire_device(&unresolved[ct], dev);
884 __aarp_expire_device(&proxies[ct], dev);
885 }
887 write_unlock_bh(&aarp_lock);
888 }
890 #ifdef CONFIG_PROC_FS
891 struct aarp_iter_state {
892 int bucket;
893 struct aarp_entry **table;
894 };
896 /*
897 * Get the aarp entry that is in the chain described
898 * by the iterator.
899 * If pos is set then skip till that index.
900 * pos = 1 is the first entry
901 */
902 static struct aarp_entry *iter_next(struct aarp_iter_state *iter, loff_t *pos)
903 {
904 int ct = iter->bucket;
905 struct aarp_entry **table = iter->table;
906 loff_t off = 0;
907 struct aarp_entry *entry;
909 rescan:
910 while(ct < AARP_HASH_SIZE) {
911 for (entry = table[ct]; entry; entry = entry->next) {
912 if (!pos || ++off == *pos) {
913 iter->table = table;
914 iter->bucket = ct;
915 return entry;
916 }
917 }
918 ++ct;
919 }
921 if (table == resolved) {
922 ct = 0;
923 table = unresolved;
924 goto rescan;
925 }
926 if (table == unresolved) {
927 ct = 0;
928 table = proxies;
929 goto rescan;
930 }
931 return NULL;
932 }
934 static void *aarp_seq_start(struct seq_file *seq, loff_t *pos)
935 {
936 struct aarp_iter_state *iter = seq->private;
938 read_lock_bh(&aarp_lock);
939 iter->table = resolved;
940 iter->bucket = 0;
942 return *pos ? iter_next(iter, pos) : SEQ_START_TOKEN;
943 }
945 static void *aarp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
946 {
947 struct aarp_entry *entry = v;
948 struct aarp_iter_state *iter = seq->private;
950 ++*pos;
952 /* first line after header */
953 if (v == SEQ_START_TOKEN)
954 entry = iter_next(iter, NULL);
956 /* next entry in current bucket */
957 else if (entry->next)
958 entry = entry->next;
960 /* next bucket or table */
961 else {
962 ++iter->bucket;
963 entry = iter_next(iter, NULL);
964 }
965 return entry;
966 }
968 static void aarp_seq_stop(struct seq_file *seq, void *v)
969 {
970 read_unlock_bh(&aarp_lock);
971 }
973 static const char *dt2str(unsigned long ticks)
974 {
975 static char buf[32];
977 sprintf(buf, "%ld.%02ld", ticks / HZ, ((ticks % HZ) * 100 ) / HZ);
979 return buf;
980 }
982 static int aarp_seq_show(struct seq_file *seq, void *v)
983 {
984 struct aarp_iter_state *iter = seq->private;
985 struct aarp_entry *entry = v;
986 unsigned long now = jiffies;
988 if (v == SEQ_START_TOKEN)
989 seq_puts(seq,
990 "Address Interface Hardware Address"
991 " Expires LastSend Retry Status\n");
992 else {
993 seq_printf(seq, "%04X:%02X %-12s",
994 ntohs(entry->target_addr.s_net),
995 (unsigned int) entry->target_addr.s_node,
996 entry->dev ? entry->dev->name : "????");
997 seq_printf(seq, "%02X:%02X:%02X:%02X:%02X:%02X",
998 entry->hwaddr[0] & 0xFF,
999 entry->hwaddr[1] & 0xFF,
1000 entry->hwaddr[2] & 0xFF,
1001 entry->hwaddr[3] & 0xFF,
1002 entry->hwaddr[4] & 0xFF,
1003 entry->hwaddr[5] & 0xFF);
1004 seq_printf(seq, " %8s",
1005 dt2str((long)entry->expires_at - (long)now));
1006 if (iter->table == unresolved)
1007 seq_printf(seq, " %8s %6hu",
1008 dt2str(now - entry->last_sent),
1009 entry->xmit_count);
1010 else
1011 seq_puts(seq, " ");
1012 seq_printf(seq, " %s\n",
1013 (iter->table == resolved) ? "resolved"
1014 : (iter->table == unresolved) ? "unresolved"
1015 : (iter->table == proxies) ? "proxies"
1016 : "unknown");
1018 return 0;
1021 static struct seq_operations aarp_seq_ops = {
1022 .start = aarp_seq_start,
1023 .next = aarp_seq_next,
1024 .stop = aarp_seq_stop,
1025 .show = aarp_seq_show,
1026 };
1028 static int aarp_seq_open(struct inode *inode, struct file *file)
1030 struct seq_file *seq;
1031 int rc = -ENOMEM;
1032 struct aarp_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
1034 if (!s)
1035 goto out;
1037 rc = seq_open(file, &aarp_seq_ops);
1038 if (rc)
1039 goto out_kfree;
1041 seq = file->private_data;
1042 seq->private = s;
1043 memset(s, 0, sizeof(*s));
1044 out:
1045 return rc;
1046 out_kfree:
1047 kfree(s);
1048 goto out;
1051 struct file_operations atalk_seq_arp_fops = {
1052 .owner = THIS_MODULE,
1053 .open = aarp_seq_open,
1054 .read = seq_read,
1055 .llseek = seq_lseek,
1056 .release = seq_release_private,
1057 };
1058 #endif
1060 /* General module cleanup. Called from cleanup_module() in ddp.c. */
1061 void aarp_cleanup_module(void)
1063 del_timer_sync(&aarp_timer);
1064 unregister_netdevice_notifier(&aarp_notifier);
1065 unregister_snap_client(aarp_dl);
1066 aarp_purge();