Commit | Line | Data |
---|---|---|
1da177e4 LT |
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 | */ | |
31 | ||
1da177e4 | 32 | #include <linux/if_arp.h> |
5a0e3ad6 | 33 | #include <linux/slab.h> |
1da177e4 LT |
34 | #include <net/sock.h> |
35 | #include <net/datalink.h> | |
36 | #include <net/psnap.h> | |
37 | #include <linux/atalk.h> | |
285b3afe | 38 | #include <linux/delay.h> |
1da177e4 LT |
39 | #include <linux/init.h> |
40 | #include <linux/proc_fs.h> | |
41 | #include <linux/seq_file.h> | |
bc3b2d7f | 42 | #include <linux/export.h> |
9be68c1a | 43 | #include <linux/etherdevice.h> |
1da177e4 LT |
44 | |
45 | int sysctl_aarp_expiry_time = AARP_EXPIRY_TIME; | |
46 | int sysctl_aarp_tick_time = AARP_TICK_TIME; | |
47 | int sysctl_aarp_retransmit_limit = AARP_RETRANSMIT_LIMIT; | |
48 | int sysctl_aarp_resolve_time = AARP_RESOLVE_TIME; | |
49 | ||
50 | /* Lists of aarp entries */ | |
51 | /** | |
52 | * struct aarp_entry - AARP entry | |
53 | * @last_sent - Last time we xmitted the aarp request | |
54 | * @packet_queue - Queue of frames wait for resolution | |
55 | * @status - Used for proxy AARP | |
56 | * expires_at - Entry expiry time | |
57 | * target_addr - DDP Address | |
58 | * dev - Device to use | |
59 | * hwaddr - Physical i/f address of target/router | |
60 | * xmit_count - When this hits 10 we give up | |
61 | * next - Next entry in chain | |
62 | */ | |
63 | struct aarp_entry { | |
64 | /* These first two are only used for unresolved entries */ | |
65 | unsigned long last_sent; | |
66 | struct sk_buff_head packet_queue; | |
67 | int status; | |
68 | unsigned long expires_at; | |
69 | struct atalk_addr target_addr; | |
70 | struct net_device *dev; | |
90ccb6aa | 71 | char hwaddr[ETH_ALEN]; |
1da177e4 LT |
72 | unsigned short xmit_count; |
73 | struct aarp_entry *next; | |
74 | }; | |
75 | ||
76 | /* Hashed list of resolved, unresolved and proxy entries */ | |
77 | static struct aarp_entry *resolved[AARP_HASH_SIZE]; | |
78 | static struct aarp_entry *unresolved[AARP_HASH_SIZE]; | |
79 | static struct aarp_entry *proxies[AARP_HASH_SIZE]; | |
80 | static int unresolved_count; | |
81 | ||
82 | /* One lock protects it all. */ | |
83 | static DEFINE_RWLOCK(aarp_lock); | |
84 | ||
85 | /* Used to walk the list and purge/kick entries. */ | |
86 | static struct timer_list aarp_timer; | |
87 | ||
88 | /* | |
89 | * Delete an aarp queue | |
90 | * | |
91 | * Must run under aarp_lock. | |
92 | */ | |
93 | static void __aarp_expire(struct aarp_entry *a) | |
94 | { | |
95 | skb_queue_purge(&a->packet_queue); | |
96 | kfree(a); | |
97 | } | |
98 | ||
99 | /* | |
100 | * Send an aarp queue entry request | |
101 | * | |
102 | * Must run under aarp_lock. | |
103 | */ | |
104 | static void __aarp_send_query(struct aarp_entry *a) | |
105 | { | |
106 | static unsigned char aarp_eth_multicast[ETH_ALEN] = | |
107 | { 0x09, 0x00, 0x07, 0xFF, 0xFF, 0xFF }; | |
108 | struct net_device *dev = a->dev; | |
109 | struct elapaarp *eah; | |
110 | int len = dev->hard_header_len + sizeof(*eah) + aarp_dl->header_length; | |
111 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
112 | struct atalk_addr *sat = atalk_find_dev_addr(dev); | |
113 | ||
114 | if (!skb) | |
115 | return; | |
116 | ||
117 | if (!sat) { | |
118 | kfree_skb(skb); | |
119 | return; | |
120 | } | |
121 | ||
122 | /* Set up the buffer */ | |
123 | skb_reserve(skb, dev->hard_header_len + aarp_dl->header_length); | |
7e28ecc2 | 124 | skb_reset_network_header(skb); |
badff6d0 | 125 | skb_reset_transport_header(skb); |
7e28ecc2 | 126 | skb_put(skb, sizeof(*eah)); |
1da177e4 LT |
127 | skb->protocol = htons(ETH_P_ATALK); |
128 | skb->dev = dev; | |
129 | eah = aarp_hdr(skb); | |
130 | ||
131 | /* Set up the ARP */ | |
132 | eah->hw_type = htons(AARP_HW_TYPE_ETHERNET); | |
133 | eah->pa_type = htons(ETH_P_ATALK); | |
134 | eah->hw_len = ETH_ALEN; | |
135 | eah->pa_len = AARP_PA_ALEN; | |
136 | eah->function = htons(AARP_REQUEST); | |
137 | ||
90ccb6aa | 138 | ether_addr_copy(eah->hw_src, dev->dev_addr); |
1da177e4 LT |
139 | |
140 | eah->pa_src_zero = 0; | |
141 | eah->pa_src_net = sat->s_net; | |
142 | eah->pa_src_node = sat->s_node; | |
143 | ||
1a73de07 | 144 | eth_zero_addr(eah->hw_dst); |
1da177e4 LT |
145 | |
146 | eah->pa_dst_zero = 0; | |
147 | eah->pa_dst_net = a->target_addr.s_net; | |
148 | eah->pa_dst_node = a->target_addr.s_node; | |
149 | ||
150 | /* Send it */ | |
151 | aarp_dl->request(aarp_dl, skb, aarp_eth_multicast); | |
152 | /* Update the sending count */ | |
153 | a->xmit_count++; | |
154 | a->last_sent = jiffies; | |
155 | } | |
156 | ||
157 | /* This runs under aarp_lock and in softint context, so only atomic memory | |
158 | * allocations can be used. */ | |
159 | static void aarp_send_reply(struct net_device *dev, struct atalk_addr *us, | |
160 | struct atalk_addr *them, unsigned char *sha) | |
161 | { | |
162 | struct elapaarp *eah; | |
163 | int len = dev->hard_header_len + sizeof(*eah) + aarp_dl->header_length; | |
164 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
165 | ||
166 | if (!skb) | |
167 | return; | |
168 | ||
169 | /* Set up the buffer */ | |
170 | skb_reserve(skb, dev->hard_header_len + aarp_dl->header_length); | |
7e28ecc2 | 171 | skb_reset_network_header(skb); |
badff6d0 | 172 | skb_reset_transport_header(skb); |
7e28ecc2 | 173 | skb_put(skb, sizeof(*eah)); |
1da177e4 LT |
174 | skb->protocol = htons(ETH_P_ATALK); |
175 | skb->dev = dev; | |
176 | eah = aarp_hdr(skb); | |
177 | ||
178 | /* Set up the ARP */ | |
179 | eah->hw_type = htons(AARP_HW_TYPE_ETHERNET); | |
180 | eah->pa_type = htons(ETH_P_ATALK); | |
181 | eah->hw_len = ETH_ALEN; | |
182 | eah->pa_len = AARP_PA_ALEN; | |
183 | eah->function = htons(AARP_REPLY); | |
184 | ||
90ccb6aa | 185 | ether_addr_copy(eah->hw_src, dev->dev_addr); |
1da177e4 LT |
186 | |
187 | eah->pa_src_zero = 0; | |
188 | eah->pa_src_net = us->s_net; | |
189 | eah->pa_src_node = us->s_node; | |
190 | ||
191 | if (!sha) | |
1a73de07 | 192 | eth_zero_addr(eah->hw_dst); |
1da177e4 | 193 | else |
90ccb6aa | 194 | ether_addr_copy(eah->hw_dst, sha); |
1da177e4 LT |
195 | |
196 | eah->pa_dst_zero = 0; | |
197 | eah->pa_dst_net = them->s_net; | |
198 | eah->pa_dst_node = them->s_node; | |
199 | ||
200 | /* Send it */ | |
201 | aarp_dl->request(aarp_dl, skb, sha); | |
202 | } | |
203 | ||
204 | /* | |
205 | * Send probe frames. Called from aarp_probe_network and | |
206 | * aarp_proxy_probe_network. | |
207 | */ | |
208 | ||
209 | static void aarp_send_probe(struct net_device *dev, struct atalk_addr *us) | |
210 | { | |
211 | struct elapaarp *eah; | |
212 | int len = dev->hard_header_len + sizeof(*eah) + aarp_dl->header_length; | |
213 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
214 | static unsigned char aarp_eth_multicast[ETH_ALEN] = | |
215 | { 0x09, 0x00, 0x07, 0xFF, 0xFF, 0xFF }; | |
216 | ||
217 | if (!skb) | |
218 | return; | |
219 | ||
220 | /* Set up the buffer */ | |
221 | skb_reserve(skb, dev->hard_header_len + aarp_dl->header_length); | |
7e28ecc2 | 222 | skb_reset_network_header(skb); |
badff6d0 | 223 | skb_reset_transport_header(skb); |
7e28ecc2 | 224 | skb_put(skb, sizeof(*eah)); |
1da177e4 LT |
225 | skb->protocol = htons(ETH_P_ATALK); |
226 | skb->dev = dev; | |
227 | eah = aarp_hdr(skb); | |
228 | ||
229 | /* Set up the ARP */ | |
230 | eah->hw_type = htons(AARP_HW_TYPE_ETHERNET); | |
231 | eah->pa_type = htons(ETH_P_ATALK); | |
232 | eah->hw_len = ETH_ALEN; | |
233 | eah->pa_len = AARP_PA_ALEN; | |
234 | eah->function = htons(AARP_PROBE); | |
235 | ||
90ccb6aa | 236 | ether_addr_copy(eah->hw_src, dev->dev_addr); |
1da177e4 LT |
237 | |
238 | eah->pa_src_zero = 0; | |
239 | eah->pa_src_net = us->s_net; | |
240 | eah->pa_src_node = us->s_node; | |
241 | ||
1a73de07 | 242 | eth_zero_addr(eah->hw_dst); |
1da177e4 LT |
243 | |
244 | eah->pa_dst_zero = 0; | |
245 | eah->pa_dst_net = us->s_net; | |
246 | eah->pa_dst_node = us->s_node; | |
247 | ||
248 | /* Send it */ | |
249 | aarp_dl->request(aarp_dl, skb, aarp_eth_multicast); | |
250 | } | |
251 | ||
252 | /* | |
253 | * Handle an aarp timer expire | |
254 | * | |
255 | * Must run under the aarp_lock. | |
256 | */ | |
257 | ||
258 | static void __aarp_expire_timer(struct aarp_entry **n) | |
259 | { | |
260 | struct aarp_entry *t; | |
261 | ||
262 | while (*n) | |
263 | /* Expired ? */ | |
264 | if (time_after(jiffies, (*n)->expires_at)) { | |
265 | t = *n; | |
266 | *n = (*n)->next; | |
267 | __aarp_expire(t); | |
268 | } else | |
269 | n = &((*n)->next); | |
270 | } | |
271 | ||
272 | /* | |
273 | * Kick all pending requests 5 times a second. | |
274 | * | |
275 | * Must run under the aarp_lock. | |
276 | */ | |
277 | static void __aarp_kick(struct aarp_entry **n) | |
278 | { | |
279 | struct aarp_entry *t; | |
280 | ||
281 | while (*n) | |
282 | /* Expired: if this will be the 11th tx, we delete instead. */ | |
283 | if ((*n)->xmit_count >= sysctl_aarp_retransmit_limit) { | |
284 | t = *n; | |
285 | *n = (*n)->next; | |
286 | __aarp_expire(t); | |
287 | } else { | |
288 | __aarp_send_query(*n); | |
289 | n = &((*n)->next); | |
290 | } | |
291 | } | |
292 | ||
293 | /* | |
294 | * A device has gone down. Take all entries referring to the device | |
295 | * and remove them. | |
296 | * | |
297 | * Must run under the aarp_lock. | |
298 | */ | |
299 | static void __aarp_expire_device(struct aarp_entry **n, struct net_device *dev) | |
300 | { | |
301 | struct aarp_entry *t; | |
302 | ||
303 | while (*n) | |
304 | if ((*n)->dev == dev) { | |
305 | t = *n; | |
306 | *n = (*n)->next; | |
307 | __aarp_expire(t); | |
308 | } else | |
309 | n = &((*n)->next); | |
310 | } | |
311 | ||
312 | /* Handle the timer event */ | |
313 | static void aarp_expire_timeout(unsigned long unused) | |
314 | { | |
315 | int ct; | |
316 | ||
317 | write_lock_bh(&aarp_lock); | |
318 | ||
319 | for (ct = 0; ct < AARP_HASH_SIZE; ct++) { | |
320 | __aarp_expire_timer(&resolved[ct]); | |
321 | __aarp_kick(&unresolved[ct]); | |
322 | __aarp_expire_timer(&unresolved[ct]); | |
323 | __aarp_expire_timer(&proxies[ct]); | |
324 | } | |
325 | ||
326 | write_unlock_bh(&aarp_lock); | |
327 | mod_timer(&aarp_timer, jiffies + | |
328 | (unresolved_count ? sysctl_aarp_tick_time : | |
329 | sysctl_aarp_expiry_time)); | |
330 | } | |
331 | ||
332 | /* Network device notifier chain handler. */ | |
333 | static int aarp_device_event(struct notifier_block *this, unsigned long event, | |
334 | void *ptr) | |
335 | { | |
351638e7 | 336 | struct net_device *dev = netdev_notifier_info_to_dev(ptr); |
1da177e4 LT |
337 | int ct; |
338 | ||
721499e8 | 339 | if (!net_eq(dev_net(dev), &init_net)) |
e9dc8653 EB |
340 | return NOTIFY_DONE; |
341 | ||
1da177e4 LT |
342 | if (event == NETDEV_DOWN) { |
343 | write_lock_bh(&aarp_lock); | |
344 | ||
345 | for (ct = 0; ct < AARP_HASH_SIZE; ct++) { | |
890d52d3 EB |
346 | __aarp_expire_device(&resolved[ct], dev); |
347 | __aarp_expire_device(&unresolved[ct], dev); | |
348 | __aarp_expire_device(&proxies[ct], dev); | |
1da177e4 LT |
349 | } |
350 | ||
351 | write_unlock_bh(&aarp_lock); | |
352 | } | |
353 | return NOTIFY_DONE; | |
354 | } | |
355 | ||
356 | /* Expire all entries in a hash chain */ | |
357 | static void __aarp_expire_all(struct aarp_entry **n) | |
358 | { | |
359 | struct aarp_entry *t; | |
360 | ||
361 | while (*n) { | |
362 | t = *n; | |
363 | *n = (*n)->next; | |
364 | __aarp_expire(t); | |
365 | } | |
366 | } | |
367 | ||
368 | /* Cleanup all hash chains -- module unloading */ | |
369 | static void aarp_purge(void) | |
370 | { | |
371 | int ct; | |
372 | ||
373 | write_lock_bh(&aarp_lock); | |
374 | for (ct = 0; ct < AARP_HASH_SIZE; ct++) { | |
375 | __aarp_expire_all(&resolved[ct]); | |
376 | __aarp_expire_all(&unresolved[ct]); | |
377 | __aarp_expire_all(&proxies[ct]); | |
378 | } | |
379 | write_unlock_bh(&aarp_lock); | |
380 | } | |
381 | ||
382 | /* | |
383 | * Create a new aarp entry. This must use GFP_ATOMIC because it | |
384 | * runs while holding spinlocks. | |
385 | */ | |
386 | static struct aarp_entry *aarp_alloc(void) | |
387 | { | |
388 | struct aarp_entry *a = kmalloc(sizeof(*a), GFP_ATOMIC); | |
389 | ||
390 | if (a) | |
391 | skb_queue_head_init(&a->packet_queue); | |
392 | return a; | |
393 | } | |
394 | ||
395 | /* | |
396 | * Find an entry. We might return an expired but not yet purged entry. We | |
397 | * don't care as it will do no harm. | |
398 | * | |
399 | * This must run under the aarp_lock. | |
400 | */ | |
401 | static struct aarp_entry *__aarp_find_entry(struct aarp_entry *list, | |
402 | struct net_device *dev, | |
403 | struct atalk_addr *sat) | |
404 | { | |
405 | while (list) { | |
406 | if (list->target_addr.s_net == sat->s_net && | |
407 | list->target_addr.s_node == sat->s_node && | |
408 | list->dev == dev) | |
409 | break; | |
410 | list = list->next; | |
411 | } | |
412 | ||
413 | return list; | |
414 | } | |
415 | ||
416 | /* Called from the DDP code, and thus must be exported. */ | |
417 | void aarp_proxy_remove(struct net_device *dev, struct atalk_addr *sa) | |
418 | { | |
419 | int hash = sa->s_node % (AARP_HASH_SIZE - 1); | |
420 | struct aarp_entry *a; | |
421 | ||
422 | write_lock_bh(&aarp_lock); | |
423 | ||
424 | a = __aarp_find_entry(proxies[hash], dev, sa); | |
425 | if (a) | |
426 | a->expires_at = jiffies - 1; | |
427 | ||
428 | write_unlock_bh(&aarp_lock); | |
429 | } | |
430 | ||
431 | /* This must run under aarp_lock. */ | |
432 | static struct atalk_addr *__aarp_proxy_find(struct net_device *dev, | |
433 | struct atalk_addr *sa) | |
434 | { | |
435 | int hash = sa->s_node % (AARP_HASH_SIZE - 1); | |
436 | struct aarp_entry *a = __aarp_find_entry(proxies[hash], dev, sa); | |
437 | ||
438 | return a ? sa : NULL; | |
439 | } | |
440 | ||
441 | /* | |
442 | * Probe a Phase 1 device or a device that requires its Net:Node to | |
443 | * be set via an ioctl. | |
444 | */ | |
445 | static void aarp_send_probe_phase1(struct atalk_iface *iface) | |
446 | { | |
447 | struct ifreq atreq; | |
448 | struct sockaddr_at *sa = (struct sockaddr_at *)&atreq.ifr_addr; | |
03b35ccb | 449 | const struct net_device_ops *ops = iface->dev->netdev_ops; |
1da177e4 LT |
450 | |
451 | sa->sat_addr.s_node = iface->address.s_node; | |
452 | sa->sat_addr.s_net = ntohs(iface->address.s_net); | |
453 | ||
454 | /* We pass the Net:Node to the drivers/cards by a Device ioctl. */ | |
03b35ccb SH |
455 | if (!(ops->ndo_do_ioctl(iface->dev, &atreq, SIOCSIFADDR))) { |
456 | ops->ndo_do_ioctl(iface->dev, &atreq, SIOCGIFADDR); | |
1da177e4 LT |
457 | if (iface->address.s_net != htons(sa->sat_addr.s_net) || |
458 | iface->address.s_node != sa->sat_addr.s_node) | |
459 | iface->status |= ATIF_PROBE_FAIL; | |
460 | ||
461 | iface->address.s_net = htons(sa->sat_addr.s_net); | |
462 | iface->address.s_node = sa->sat_addr.s_node; | |
463 | } | |
464 | } | |
465 | ||
466 | ||
467 | void aarp_probe_network(struct atalk_iface *atif) | |
468 | { | |
469 | if (atif->dev->type == ARPHRD_LOCALTLK || | |
470 | atif->dev->type == ARPHRD_PPP) | |
471 | aarp_send_probe_phase1(atif); | |
472 | else { | |
473 | unsigned int count; | |
474 | ||
475 | for (count = 0; count < AARP_RETRANSMIT_LIMIT; count++) { | |
476 | aarp_send_probe(atif->dev, &atif->address); | |
477 | ||
478 | /* Defer 1/10th */ | |
285b3afe | 479 | msleep(100); |
1da177e4 LT |
480 | |
481 | if (atif->status & ATIF_PROBE_FAIL) | |
482 | break; | |
483 | } | |
484 | } | |
485 | } | |
486 | ||
487 | int aarp_proxy_probe_network(struct atalk_iface *atif, struct atalk_addr *sa) | |
488 | { | |
489 | int hash, retval = -EPROTONOSUPPORT; | |
490 | struct aarp_entry *entry; | |
491 | unsigned int count; | |
492 | ||
493 | /* | |
494 | * we don't currently support LocalTalk or PPP for proxy AARP; | |
495 | * if someone wants to try and add it, have fun | |
496 | */ | |
497 | if (atif->dev->type == ARPHRD_LOCALTLK || | |
498 | atif->dev->type == ARPHRD_PPP) | |
499 | goto out; | |
500 | ||
501 | /* | |
502 | * create a new AARP entry with the flags set to be published -- | |
503 | * we need this one to hang around even if it's in use | |
504 | */ | |
505 | entry = aarp_alloc(); | |
506 | retval = -ENOMEM; | |
507 | if (!entry) | |
508 | goto out; | |
509 | ||
510 | entry->expires_at = -1; | |
511 | entry->status = ATIF_PROBE; | |
512 | entry->target_addr.s_node = sa->s_node; | |
513 | entry->target_addr.s_net = sa->s_net; | |
514 | entry->dev = atif->dev; | |
515 | ||
516 | write_lock_bh(&aarp_lock); | |
517 | ||
518 | hash = sa->s_node % (AARP_HASH_SIZE - 1); | |
519 | entry->next = proxies[hash]; | |
520 | proxies[hash] = entry; | |
521 | ||
522 | for (count = 0; count < AARP_RETRANSMIT_LIMIT; count++) { | |
523 | aarp_send_probe(atif->dev, sa); | |
524 | ||
525 | /* Defer 1/10th */ | |
1da177e4 | 526 | write_unlock_bh(&aarp_lock); |
285b3afe | 527 | msleep(100); |
1da177e4 LT |
528 | write_lock_bh(&aarp_lock); |
529 | ||
530 | if (entry->status & ATIF_PROBE_FAIL) | |
531 | break; | |
532 | } | |
533 | ||
534 | if (entry->status & ATIF_PROBE_FAIL) { | |
535 | entry->expires_at = jiffies - 1; /* free the entry */ | |
536 | retval = -EADDRINUSE; /* return network full */ | |
537 | } else { /* clear the probing flag */ | |
538 | entry->status &= ~ATIF_PROBE; | |
539 | retval = 1; | |
540 | } | |
541 | ||
542 | write_unlock_bh(&aarp_lock); | |
543 | out: | |
544 | return retval; | |
545 | } | |
546 | ||
547 | /* Send a DDP frame */ | |
548 | int aarp_send_ddp(struct net_device *dev, struct sk_buff *skb, | |
549 | struct atalk_addr *sa, void *hwaddr) | |
550 | { | |
551 | static char ddp_eth_multicast[ETH_ALEN] = | |
552 | { 0x09, 0x00, 0x07, 0xFF, 0xFF, 0xFF }; | |
553 | int hash; | |
554 | struct aarp_entry *a; | |
555 | ||
c1d2bbe1 | 556 | skb_reset_network_header(skb); |
1da177e4 LT |
557 | |
558 | /* Check for LocalTalk first */ | |
559 | if (dev->type == ARPHRD_LOCALTLK) { | |
560 | struct atalk_addr *at = atalk_find_dev_addr(dev); | |
561 | struct ddpehdr *ddp = (struct ddpehdr *)skb->data; | |
562 | int ft = 2; | |
563 | ||
564 | /* | |
565 | * Compressible ? | |
566 | * | |
567 | * IFF: src_net == dest_net == device_net | |
568 | * (zero matches anything) | |
569 | */ | |
570 | ||
571 | if ((!ddp->deh_snet || at->s_net == ddp->deh_snet) && | |
572 | (!ddp->deh_dnet || at->s_net == ddp->deh_dnet)) { | |
573 | skb_pull(skb, sizeof(*ddp) - 4); | |
574 | ||
575 | /* | |
576 | * The upper two remaining bytes are the port | |
577 | * numbers we just happen to need. Now put the | |
578 | * length in the lower two. | |
579 | */ | |
f6e276ee | 580 | *((__be16 *)skb->data) = htons(skb->len); |
1da177e4 LT |
581 | ft = 1; |
582 | } | |
583 | /* | |
584 | * Nice and easy. No AARP type protocols occur here so we can | |
585 | * just shovel it out with a 3 byte LLAP header | |
586 | */ | |
587 | ||
588 | skb_push(skb, 3); | |
589 | skb->data[0] = sa->s_node; | |
590 | skb->data[1] = at->s_node; | |
591 | skb->data[2] = ft; | |
592 | skb->dev = dev; | |
593 | goto sendit; | |
594 | } | |
595 | ||
596 | /* On a PPP link we neither compress nor aarp. */ | |
597 | if (dev->type == ARPHRD_PPP) { | |
598 | skb->protocol = htons(ETH_P_PPPTALK); | |
599 | skb->dev = dev; | |
600 | goto sendit; | |
601 | } | |
602 | ||
603 | /* Non ELAP we cannot do. */ | |
604 | if (dev->type != ARPHRD_ETHER) | |
ffcfb8db | 605 | goto free_it; |
1da177e4 LT |
606 | |
607 | skb->dev = dev; | |
608 | skb->protocol = htons(ETH_P_ATALK); | |
609 | hash = sa->s_node % (AARP_HASH_SIZE - 1); | |
610 | ||
611 | /* Do we have a resolved entry? */ | |
612 | if (sa->s_node == ATADDR_BCAST) { | |
613 | /* Send it */ | |
614 | ddp_dl->request(ddp_dl, skb, ddp_eth_multicast); | |
615 | goto sent; | |
616 | } | |
617 | ||
618 | write_lock_bh(&aarp_lock); | |
619 | a = __aarp_find_entry(resolved[hash], dev, sa); | |
620 | ||
621 | if (a) { /* Return 1 and fill in the address */ | |
622 | a->expires_at = jiffies + (sysctl_aarp_expiry_time * 10); | |
623 | ddp_dl->request(ddp_dl, skb, a->hwaddr); | |
624 | write_unlock_bh(&aarp_lock); | |
625 | goto sent; | |
626 | } | |
627 | ||
628 | /* Do we have an unresolved entry: This is the less common path */ | |
629 | a = __aarp_find_entry(unresolved[hash], dev, sa); | |
630 | if (a) { /* Queue onto the unresolved queue */ | |
631 | skb_queue_tail(&a->packet_queue, skb); | |
632 | goto out_unlock; | |
633 | } | |
634 | ||
635 | /* Allocate a new entry */ | |
636 | a = aarp_alloc(); | |
637 | if (!a) { | |
638 | /* Whoops slipped... good job it's an unreliable protocol 8) */ | |
639 | write_unlock_bh(&aarp_lock); | |
ffcfb8db | 640 | goto free_it; |
1da177e4 LT |
641 | } |
642 | ||
643 | /* Set up the queue */ | |
644 | skb_queue_tail(&a->packet_queue, skb); | |
645 | a->expires_at = jiffies + sysctl_aarp_resolve_time; | |
646 | a->dev = dev; | |
647 | a->next = unresolved[hash]; | |
648 | a->target_addr = *sa; | |
649 | a->xmit_count = 0; | |
650 | unresolved[hash] = a; | |
651 | unresolved_count++; | |
652 | ||
653 | /* Send an initial request for the address */ | |
654 | __aarp_send_query(a); | |
655 | ||
656 | /* | |
657 | * Switch to fast timer if needed (That is if this is the first | |
658 | * unresolved entry to get added) | |
659 | */ | |
660 | ||
661 | if (unresolved_count == 1) | |
662 | mod_timer(&aarp_timer, jiffies + sysctl_aarp_tick_time); | |
663 | ||
664 | /* Now finally, it is safe to drop the lock. */ | |
665 | out_unlock: | |
666 | write_unlock_bh(&aarp_lock); | |
667 | ||
668 | /* Tell the ddp layer we have taken over for this frame. */ | |
ffcfb8db | 669 | goto sent; |
1da177e4 LT |
670 | |
671 | sendit: | |
672 | if (skb->sk) | |
673 | skb->priority = skb->sk->sk_priority; | |
ffcfb8db ACM |
674 | if (dev_queue_xmit(skb)) |
675 | goto drop; | |
1da177e4 | 676 | sent: |
ffcfb8db ACM |
677 | return NET_XMIT_SUCCESS; |
678 | free_it: | |
679 | kfree_skb(skb); | |
680 | drop: | |
681 | return NET_XMIT_DROP; | |
1da177e4 | 682 | } |
ffcfb8db | 683 | EXPORT_SYMBOL(aarp_send_ddp); |
1da177e4 LT |
684 | |
685 | /* | |
686 | * An entry in the aarp unresolved queue has become resolved. Send | |
687 | * all the frames queued under it. | |
688 | * | |
689 | * Must run under aarp_lock. | |
690 | */ | |
691 | static void __aarp_resolved(struct aarp_entry **list, struct aarp_entry *a, | |
692 | int hash) | |
693 | { | |
694 | struct sk_buff *skb; | |
695 | ||
696 | while (*list) | |
697 | if (*list == a) { | |
698 | unresolved_count--; | |
699 | *list = a->next; | |
700 | ||
701 | /* Move into the resolved list */ | |
702 | a->next = resolved[hash]; | |
703 | resolved[hash] = a; | |
704 | ||
705 | /* Kick frames off */ | |
706 | while ((skb = skb_dequeue(&a->packet_queue)) != NULL) { | |
707 | a->expires_at = jiffies + | |
708 | sysctl_aarp_expiry_time * 10; | |
709 | ddp_dl->request(ddp_dl, skb, a->hwaddr); | |
710 | } | |
711 | } else | |
712 | list = &((*list)->next); | |
713 | } | |
714 | ||
715 | /* | |
716 | * This is called by the SNAP driver whenever we see an AARP SNAP | |
717 | * frame. We currently only support Ethernet. | |
718 | */ | |
719 | static int aarp_rcv(struct sk_buff *skb, struct net_device *dev, | |
f2ccd8fa | 720 | struct packet_type *pt, struct net_device *orig_dev) |
1da177e4 LT |
721 | { |
722 | struct elapaarp *ea = aarp_hdr(skb); | |
723 | int hash, ret = 0; | |
724 | __u16 function; | |
725 | struct aarp_entry *a; | |
726 | struct atalk_addr sa, *ma, da; | |
727 | struct atalk_iface *ifa; | |
728 | ||
721499e8 | 729 | if (!net_eq(dev_net(dev), &init_net)) |
e730c155 EB |
730 | goto out0; |
731 | ||
1da177e4 LT |
732 | /* We only do Ethernet SNAP AARP. */ |
733 | if (dev->type != ARPHRD_ETHER) | |
734 | goto out0; | |
735 | ||
736 | /* Frame size ok? */ | |
737 | if (!skb_pull(skb, sizeof(*ea))) | |
738 | goto out0; | |
739 | ||
740 | function = ntohs(ea->function); | |
741 | ||
742 | /* Sanity check fields. */ | |
743 | if (function < AARP_REQUEST || function > AARP_PROBE || | |
744 | ea->hw_len != ETH_ALEN || ea->pa_len != AARP_PA_ALEN || | |
745 | ea->pa_src_zero || ea->pa_dst_zero) | |
746 | goto out0; | |
747 | ||
748 | /* Looks good. */ | |
749 | hash = ea->pa_src_node % (AARP_HASH_SIZE - 1); | |
750 | ||
751 | /* Build an address. */ | |
752 | sa.s_node = ea->pa_src_node; | |
753 | sa.s_net = ea->pa_src_net; | |
754 | ||
755 | /* Process the packet. Check for replies of me. */ | |
756 | ifa = atalk_find_dev(dev); | |
757 | if (!ifa) | |
758 | goto out1; | |
759 | ||
760 | if (ifa->status & ATIF_PROBE && | |
761 | ifa->address.s_node == ea->pa_dst_node && | |
762 | ifa->address.s_net == ea->pa_dst_net) { | |
763 | ifa->status |= ATIF_PROBE_FAIL; /* Fail the probe (in use) */ | |
764 | goto out1; | |
765 | } | |
766 | ||
767 | /* Check for replies of proxy AARP entries */ | |
768 | da.s_node = ea->pa_dst_node; | |
769 | da.s_net = ea->pa_dst_net; | |
770 | ||
771 | write_lock_bh(&aarp_lock); | |
772 | a = __aarp_find_entry(proxies[hash], dev, &da); | |
773 | ||
774 | if (a && a->status & ATIF_PROBE) { | |
775 | a->status |= ATIF_PROBE_FAIL; | |
776 | /* | |
777 | * we do not respond to probe or request packets for | |
778 | * this address while we are probing this address | |
779 | */ | |
780 | goto unlock; | |
781 | } | |
782 | ||
783 | switch (function) { | |
4a9e4b09 JP |
784 | case AARP_REPLY: |
785 | if (!unresolved_count) /* Speed up */ | |
786 | break; | |
1da177e4 | 787 | |
4a9e4b09 JP |
788 | /* Find the entry. */ |
789 | a = __aarp_find_entry(unresolved[hash], dev, &sa); | |
790 | if (!a || dev != a->dev) | |
1da177e4 LT |
791 | break; |
792 | ||
4a9e4b09 | 793 | /* We can fill one in - this is good. */ |
90ccb6aa | 794 | ether_addr_copy(a->hwaddr, ea->hw_src); |
4a9e4b09 JP |
795 | __aarp_resolved(&unresolved[hash], a, hash); |
796 | if (!unresolved_count) | |
797 | mod_timer(&aarp_timer, | |
798 | jiffies + sysctl_aarp_expiry_time); | |
799 | break; | |
800 | ||
801 | case AARP_REQUEST: | |
802 | case AARP_PROBE: | |
803 | ||
804 | /* | |
805 | * If it is my address set ma to my address and reply. | |
806 | * We can treat probe and request the same. Probe | |
807 | * simply means we shouldn't cache the querying host, | |
808 | * as in a probe they are proposing an address not | |
809 | * using one. | |
810 | * | |
811 | * Support for proxy-AARP added. We check if the | |
812 | * address is one of our proxies before we toss the | |
813 | * packet out. | |
814 | */ | |
815 | ||
816 | sa.s_node = ea->pa_dst_node; | |
817 | sa.s_net = ea->pa_dst_net; | |
818 | ||
819 | /* See if we have a matching proxy. */ | |
820 | ma = __aarp_proxy_find(dev, &sa); | |
821 | if (!ma) | |
822 | ma = &ifa->address; | |
823 | else { /* We need to make a copy of the entry. */ | |
824 | da.s_node = sa.s_node; | |
825 | da.s_net = sa.s_net; | |
826 | ma = &da; | |
827 | } | |
1da177e4 | 828 | |
4a9e4b09 | 829 | if (function == AARP_PROBE) { |
1da177e4 | 830 | /* |
4a9e4b09 JP |
831 | * A probe implies someone trying to get an |
832 | * address. So as a precaution flush any | |
833 | * entries we have for this address. | |
1da177e4 | 834 | */ |
4a9e4b09 JP |
835 | a = __aarp_find_entry(resolved[sa.s_node % |
836 | (AARP_HASH_SIZE - 1)], | |
837 | skb->dev, &sa); | |
1da177e4 | 838 | |
4a9e4b09 JP |
839 | /* |
840 | * Make it expire next tick - that avoids us | |
841 | * getting into a probe/flush/learn/probe/ | |
842 | * flush/learn cycle during probing of a slow | |
843 | * to respond host addr. | |
844 | */ | |
845 | if (a) { | |
846 | a->expires_at = jiffies - 1; | |
847 | mod_timer(&aarp_timer, jiffies + | |
848 | sysctl_aarp_tick_time); | |
1da177e4 | 849 | } |
4a9e4b09 | 850 | } |
1da177e4 | 851 | |
4a9e4b09 JP |
852 | if (sa.s_node != ma->s_node) |
853 | break; | |
1da177e4 | 854 | |
4a9e4b09 JP |
855 | if (sa.s_net && ma->s_net && sa.s_net != ma->s_net) |
856 | break; | |
1da177e4 | 857 | |
4a9e4b09 JP |
858 | sa.s_node = ea->pa_src_node; |
859 | sa.s_net = ea->pa_src_net; | |
1da177e4 | 860 | |
4a9e4b09 JP |
861 | /* aarp_my_address has found the address to use for us. |
862 | */ | |
863 | aarp_send_reply(dev, ma, &sa, ea->hw_src); | |
864 | break; | |
1da177e4 LT |
865 | } |
866 | ||
867 | unlock: | |
868 | write_unlock_bh(&aarp_lock); | |
869 | out1: | |
870 | ret = 1; | |
871 | out0: | |
872 | kfree_skb(skb); | |
873 | return ret; | |
874 | } | |
875 | ||
876 | static struct notifier_block aarp_notifier = { | |
877 | .notifier_call = aarp_device_event, | |
878 | }; | |
879 | ||
880 | static unsigned char aarp_snap_id[] = { 0x00, 0x00, 0x00, 0x80, 0xF3 }; | |
881 | ||
882 | void __init aarp_proto_init(void) | |
883 | { | |
884 | aarp_dl = register_snap_client(aarp_snap_id, aarp_rcv); | |
885 | if (!aarp_dl) | |
886 | printk(KERN_CRIT "Unable to register AARP with SNAP.\n"); | |
b24b8a24 | 887 | setup_timer(&aarp_timer, aarp_expire_timeout, 0); |
1da177e4 LT |
888 | aarp_timer.expires = jiffies + sysctl_aarp_expiry_time; |
889 | add_timer(&aarp_timer); | |
890 | register_netdevice_notifier(&aarp_notifier); | |
891 | } | |
892 | ||
893 | /* Remove the AARP entries associated with a device. */ | |
894 | void aarp_device_down(struct net_device *dev) | |
895 | { | |
896 | int ct; | |
897 | ||
898 | write_lock_bh(&aarp_lock); | |
899 | ||
900 | for (ct = 0; ct < AARP_HASH_SIZE; ct++) { | |
901 | __aarp_expire_device(&resolved[ct], dev); | |
902 | __aarp_expire_device(&unresolved[ct], dev); | |
903 | __aarp_expire_device(&proxies[ct], dev); | |
904 | } | |
905 | ||
906 | write_unlock_bh(&aarp_lock); | |
907 | } | |
908 | ||
909 | #ifdef CONFIG_PROC_FS | |
910 | struct aarp_iter_state { | |
911 | int bucket; | |
912 | struct aarp_entry **table; | |
913 | }; | |
914 | ||
915 | /* | |
916 | * Get the aarp entry that is in the chain described | |
ed4477b9 | 917 | * by the iterator. |
1da177e4 LT |
918 | * If pos is set then skip till that index. |
919 | * pos = 1 is the first entry | |
920 | */ | |
921 | static struct aarp_entry *iter_next(struct aarp_iter_state *iter, loff_t *pos) | |
922 | { | |
923 | int ct = iter->bucket; | |
924 | struct aarp_entry **table = iter->table; | |
925 | loff_t off = 0; | |
926 | struct aarp_entry *entry; | |
ed4477b9 | 927 | |
1da177e4 | 928 | rescan: |
fd1dc261 | 929 | while (ct < AARP_HASH_SIZE) { |
1da177e4 LT |
930 | for (entry = table[ct]; entry; entry = entry->next) { |
931 | if (!pos || ++off == *pos) { | |
932 | iter->table = table; | |
933 | iter->bucket = ct; | |
934 | return entry; | |
935 | } | |
936 | } | |
937 | ++ct; | |
938 | } | |
939 | ||
940 | if (table == resolved) { | |
941 | ct = 0; | |
942 | table = unresolved; | |
943 | goto rescan; | |
944 | } | |
945 | if (table == unresolved) { | |
946 | ct = 0; | |
947 | table = proxies; | |
948 | goto rescan; | |
949 | } | |
950 | return NULL; | |
951 | } | |
952 | ||
953 | static void *aarp_seq_start(struct seq_file *seq, loff_t *pos) | |
ca629f24 | 954 | __acquires(aarp_lock) |
1da177e4 LT |
955 | { |
956 | struct aarp_iter_state *iter = seq->private; | |
957 | ||
958 | read_lock_bh(&aarp_lock); | |
959 | iter->table = resolved; | |
960 | iter->bucket = 0; | |
961 | ||
962 | return *pos ? iter_next(iter, pos) : SEQ_START_TOKEN; | |
963 | } | |
964 | ||
965 | static void *aarp_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
966 | { | |
967 | struct aarp_entry *entry = v; | |
968 | struct aarp_iter_state *iter = seq->private; | |
969 | ||
970 | ++*pos; | |
971 | ||
972 | /* first line after header */ | |
ed4477b9 | 973 | if (v == SEQ_START_TOKEN) |
1da177e4 | 974 | entry = iter_next(iter, NULL); |
ed4477b9 | 975 | |
1da177e4 LT |
976 | /* next entry in current bucket */ |
977 | else if (entry->next) | |
978 | entry = entry->next; | |
979 | ||
980 | /* next bucket or table */ | |
981 | else { | |
982 | ++iter->bucket; | |
983 | entry = iter_next(iter, NULL); | |
984 | } | |
985 | return entry; | |
986 | } | |
987 | ||
988 | static void aarp_seq_stop(struct seq_file *seq, void *v) | |
ca629f24 | 989 | __releases(aarp_lock) |
1da177e4 LT |
990 | { |
991 | read_unlock_bh(&aarp_lock); | |
992 | } | |
993 | ||
994 | static const char *dt2str(unsigned long ticks) | |
995 | { | |
996 | static char buf[32]; | |
997 | ||
fd1dc261 | 998 | sprintf(buf, "%ld.%02ld", ticks / HZ, ((ticks % HZ) * 100) / HZ); |
1da177e4 LT |
999 | |
1000 | return buf; | |
1001 | } | |
1002 | ||
1003 | static int aarp_seq_show(struct seq_file *seq, void *v) | |
1004 | { | |
1005 | struct aarp_iter_state *iter = seq->private; | |
1006 | struct aarp_entry *entry = v; | |
1007 | unsigned long now = jiffies; | |
1008 | ||
1009 | if (v == SEQ_START_TOKEN) | |
ed4477b9 | 1010 | seq_puts(seq, |
1da177e4 LT |
1011 | "Address Interface Hardware Address" |
1012 | " Expires LastSend Retry Status\n"); | |
1013 | else { | |
1014 | seq_printf(seq, "%04X:%02X %-12s", | |
1015 | ntohs(entry->target_addr.s_net), | |
1016 | (unsigned int) entry->target_addr.s_node, | |
1017 | entry->dev ? entry->dev->name : "????"); | |
e174961c | 1018 | seq_printf(seq, "%pM", entry->hwaddr); |
1da177e4 LT |
1019 | seq_printf(seq, " %8s", |
1020 | dt2str((long)entry->expires_at - (long)now)); | |
1021 | if (iter->table == unresolved) | |
1022 | seq_printf(seq, " %8s %6hu", | |
1023 | dt2str(now - entry->last_sent), | |
1024 | entry->xmit_count); | |
1025 | else | |
1026 | seq_puts(seq, " "); | |
1027 | seq_printf(seq, " %s\n", | |
1028 | (iter->table == resolved) ? "resolved" | |
1029 | : (iter->table == unresolved) ? "unresolved" | |
1030 | : (iter->table == proxies) ? "proxies" | |
1031 | : "unknown"); | |
ed4477b9 | 1032 | } |
1da177e4 LT |
1033 | return 0; |
1034 | } | |
1035 | ||
56b3d975 | 1036 | static const struct seq_operations aarp_seq_ops = { |
1da177e4 LT |
1037 | .start = aarp_seq_start, |
1038 | .next = aarp_seq_next, | |
1039 | .stop = aarp_seq_stop, | |
1040 | .show = aarp_seq_show, | |
1041 | }; | |
1042 | ||
1043 | static int aarp_seq_open(struct inode *inode, struct file *file) | |
1044 | { | |
c20932d2 PE |
1045 | return seq_open_private(file, &aarp_seq_ops, |
1046 | sizeof(struct aarp_iter_state)); | |
1da177e4 LT |
1047 | } |
1048 | ||
9a32144e | 1049 | const struct file_operations atalk_seq_arp_fops = { |
1da177e4 LT |
1050 | .owner = THIS_MODULE, |
1051 | .open = aarp_seq_open, | |
1052 | .read = seq_read, | |
1053 | .llseek = seq_lseek, | |
1054 | .release = seq_release_private, | |
1055 | }; | |
1056 | #endif | |
1057 | ||
1058 | /* General module cleanup. Called from cleanup_module() in ddp.c. */ | |
1059 | void aarp_cleanup_module(void) | |
1060 | { | |
1061 | del_timer_sync(&aarp_timer); | |
1062 | unregister_netdevice_notifier(&aarp_notifier); | |
1063 | unregister_snap_client(aarp_dl); | |
1064 | aarp_purge(); | |
1065 | } |