]>
Commit | Line | Data |
---|---|---|
2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /* |
3 | * AARP: An implementation of the AppleTalk AARP protocol for | |
4 | * Ethernet 'ELAP'. | |
5 | * | |
6 | * Alan Cox <Alan.Cox@linux.org> | |
7 | * | |
8 | * This doesn't fit cleanly with the IP arp. Potentially we can use | |
9 | * the generic neighbour discovery code to clean this up. | |
10 | * | |
11 | * FIXME: | |
12 | * We ought to handle the retransmits with a single list and a | |
13 | * separate fast timer for when it is needed. | |
14 | * Use neighbour discovery code. | |
15 | * Token Ring Support. | |
16 | * | |
1da177e4 LT |
17 | * References: |
18 | * Inside AppleTalk (2nd Ed). | |
19 | * Fixes: | |
20 | * Jaume Grau - flush caches on AARP_PROBE | |
21 | * Rob Newberry - Added proxy AARP and AARP proc fs, | |
22 | * moved probing from DDP module. | |
23 | * Arnaldo C. Melo - don't mangle rx packets | |
1da177e4 LT |
24 | */ |
25 | ||
1da177e4 | 26 | #include <linux/if_arp.h> |
5a0e3ad6 | 27 | #include <linux/slab.h> |
1da177e4 LT |
28 | #include <net/sock.h> |
29 | #include <net/datalink.h> | |
30 | #include <net/psnap.h> | |
31 | #include <linux/atalk.h> | |
285b3afe | 32 | #include <linux/delay.h> |
1da177e4 LT |
33 | #include <linux/init.h> |
34 | #include <linux/proc_fs.h> | |
35 | #include <linux/seq_file.h> | |
bc3b2d7f | 36 | #include <linux/export.h> |
9be68c1a | 37 | #include <linux/etherdevice.h> |
1da177e4 LT |
38 | |
39 | int sysctl_aarp_expiry_time = AARP_EXPIRY_TIME; | |
40 | int sysctl_aarp_tick_time = AARP_TICK_TIME; | |
41 | int sysctl_aarp_retransmit_limit = AARP_RETRANSMIT_LIMIT; | |
42 | int sysctl_aarp_resolve_time = AARP_RESOLVE_TIME; | |
43 | ||
44 | /* Lists of aarp entries */ | |
45 | /** | |
46 | * struct aarp_entry - AARP entry | |
709565ae AL |
47 | * @last_sent: Last time we xmitted the aarp request |
48 | * @packet_queue: Queue of frames wait for resolution | |
49 | * @status: Used for proxy AARP | |
50 | * @expires_at: Entry expiry time | |
51 | * @target_addr: DDP Address | |
52 | * @dev: Device to use | |
53 | * @hwaddr: Physical i/f address of target/router | |
54 | * @xmit_count: When this hits 10 we give up | |
55 | * @next: Next entry in chain | |
1da177e4 LT |
56 | */ |
57 | struct aarp_entry { | |
58 | /* These first two are only used for unresolved entries */ | |
59 | unsigned long last_sent; | |
60 | struct sk_buff_head packet_queue; | |
61 | int status; | |
62 | unsigned long expires_at; | |
63 | struct atalk_addr target_addr; | |
64 | struct net_device *dev; | |
90ccb6aa | 65 | char hwaddr[ETH_ALEN]; |
1da177e4 LT |
66 | unsigned short xmit_count; |
67 | struct aarp_entry *next; | |
68 | }; | |
69 | ||
70 | /* Hashed list of resolved, unresolved and proxy entries */ | |
71 | static struct aarp_entry *resolved[AARP_HASH_SIZE]; | |
72 | static struct aarp_entry *unresolved[AARP_HASH_SIZE]; | |
73 | static struct aarp_entry *proxies[AARP_HASH_SIZE]; | |
74 | static int unresolved_count; | |
75 | ||
76 | /* One lock protects it all. */ | |
77 | static DEFINE_RWLOCK(aarp_lock); | |
78 | ||
79 | /* Used to walk the list and purge/kick entries. */ | |
80 | static struct timer_list aarp_timer; | |
81 | ||
82 | /* | |
83 | * Delete an aarp queue | |
84 | * | |
85 | * Must run under aarp_lock. | |
86 | */ | |
87 | static void __aarp_expire(struct aarp_entry *a) | |
88 | { | |
89 | skb_queue_purge(&a->packet_queue); | |
90 | kfree(a); | |
91 | } | |
92 | ||
93 | /* | |
94 | * Send an aarp queue entry request | |
95 | * | |
96 | * Must run under aarp_lock. | |
97 | */ | |
98 | static void __aarp_send_query(struct aarp_entry *a) | |
99 | { | |
100 | static unsigned char aarp_eth_multicast[ETH_ALEN] = | |
101 | { 0x09, 0x00, 0x07, 0xFF, 0xFF, 0xFF }; | |
102 | struct net_device *dev = a->dev; | |
103 | struct elapaarp *eah; | |
104 | int len = dev->hard_header_len + sizeof(*eah) + aarp_dl->header_length; | |
105 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
106 | struct atalk_addr *sat = atalk_find_dev_addr(dev); | |
107 | ||
108 | if (!skb) | |
109 | return; | |
110 | ||
111 | if (!sat) { | |
112 | kfree_skb(skb); | |
113 | return; | |
114 | } | |
115 | ||
116 | /* Set up the buffer */ | |
117 | skb_reserve(skb, dev->hard_header_len + aarp_dl->header_length); | |
7e28ecc2 | 118 | skb_reset_network_header(skb); |
badff6d0 | 119 | skb_reset_transport_header(skb); |
7e28ecc2 | 120 | skb_put(skb, sizeof(*eah)); |
1da177e4 LT |
121 | skb->protocol = htons(ETH_P_ATALK); |
122 | skb->dev = dev; | |
123 | eah = aarp_hdr(skb); | |
124 | ||
125 | /* Set up the ARP */ | |
126 | eah->hw_type = htons(AARP_HW_TYPE_ETHERNET); | |
127 | eah->pa_type = htons(ETH_P_ATALK); | |
128 | eah->hw_len = ETH_ALEN; | |
129 | eah->pa_len = AARP_PA_ALEN; | |
130 | eah->function = htons(AARP_REQUEST); | |
131 | ||
90ccb6aa | 132 | ether_addr_copy(eah->hw_src, dev->dev_addr); |
1da177e4 LT |
133 | |
134 | eah->pa_src_zero = 0; | |
135 | eah->pa_src_net = sat->s_net; | |
136 | eah->pa_src_node = sat->s_node; | |
137 | ||
1a73de07 | 138 | eth_zero_addr(eah->hw_dst); |
1da177e4 LT |
139 | |
140 | eah->pa_dst_zero = 0; | |
141 | eah->pa_dst_net = a->target_addr.s_net; | |
142 | eah->pa_dst_node = a->target_addr.s_node; | |
143 | ||
144 | /* Send it */ | |
145 | aarp_dl->request(aarp_dl, skb, aarp_eth_multicast); | |
146 | /* Update the sending count */ | |
147 | a->xmit_count++; | |
148 | a->last_sent = jiffies; | |
149 | } | |
150 | ||
151 | /* This runs under aarp_lock and in softint context, so only atomic memory | |
152 | * allocations can be used. */ | |
153 | static void aarp_send_reply(struct net_device *dev, struct atalk_addr *us, | |
154 | struct atalk_addr *them, unsigned char *sha) | |
155 | { | |
156 | struct elapaarp *eah; | |
157 | int len = dev->hard_header_len + sizeof(*eah) + aarp_dl->header_length; | |
158 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
159 | ||
160 | if (!skb) | |
161 | return; | |
162 | ||
163 | /* Set up the buffer */ | |
164 | skb_reserve(skb, dev->hard_header_len + aarp_dl->header_length); | |
7e28ecc2 | 165 | skb_reset_network_header(skb); |
badff6d0 | 166 | skb_reset_transport_header(skb); |
7e28ecc2 | 167 | skb_put(skb, sizeof(*eah)); |
1da177e4 LT |
168 | skb->protocol = htons(ETH_P_ATALK); |
169 | skb->dev = dev; | |
170 | eah = aarp_hdr(skb); | |
171 | ||
172 | /* Set up the ARP */ | |
173 | eah->hw_type = htons(AARP_HW_TYPE_ETHERNET); | |
174 | eah->pa_type = htons(ETH_P_ATALK); | |
175 | eah->hw_len = ETH_ALEN; | |
176 | eah->pa_len = AARP_PA_ALEN; | |
177 | eah->function = htons(AARP_REPLY); | |
178 | ||
90ccb6aa | 179 | ether_addr_copy(eah->hw_src, dev->dev_addr); |
1da177e4 LT |
180 | |
181 | eah->pa_src_zero = 0; | |
182 | eah->pa_src_net = us->s_net; | |
183 | eah->pa_src_node = us->s_node; | |
184 | ||
185 | if (!sha) | |
1a73de07 | 186 | eth_zero_addr(eah->hw_dst); |
1da177e4 | 187 | else |
90ccb6aa | 188 | ether_addr_copy(eah->hw_dst, sha); |
1da177e4 LT |
189 | |
190 | eah->pa_dst_zero = 0; | |
191 | eah->pa_dst_net = them->s_net; | |
192 | eah->pa_dst_node = them->s_node; | |
193 | ||
194 | /* Send it */ | |
195 | aarp_dl->request(aarp_dl, skb, sha); | |
196 | } | |
197 | ||
198 | /* | |
199 | * Send probe frames. Called from aarp_probe_network and | |
200 | * aarp_proxy_probe_network. | |
201 | */ | |
202 | ||
203 | static void aarp_send_probe(struct net_device *dev, struct atalk_addr *us) | |
204 | { | |
205 | struct elapaarp *eah; | |
206 | int len = dev->hard_header_len + sizeof(*eah) + aarp_dl->header_length; | |
207 | struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); | |
208 | static unsigned char aarp_eth_multicast[ETH_ALEN] = | |
209 | { 0x09, 0x00, 0x07, 0xFF, 0xFF, 0xFF }; | |
210 | ||
211 | if (!skb) | |
212 | return; | |
213 | ||
214 | /* Set up the buffer */ | |
215 | skb_reserve(skb, dev->hard_header_len + aarp_dl->header_length); | |
7e28ecc2 | 216 | skb_reset_network_header(skb); |
badff6d0 | 217 | skb_reset_transport_header(skb); |
7e28ecc2 | 218 | skb_put(skb, sizeof(*eah)); |
1da177e4 LT |
219 | skb->protocol = htons(ETH_P_ATALK); |
220 | skb->dev = dev; | |
221 | eah = aarp_hdr(skb); | |
222 | ||
223 | /* Set up the ARP */ | |
224 | eah->hw_type = htons(AARP_HW_TYPE_ETHERNET); | |
225 | eah->pa_type = htons(ETH_P_ATALK); | |
226 | eah->hw_len = ETH_ALEN; | |
227 | eah->pa_len = AARP_PA_ALEN; | |
228 | eah->function = htons(AARP_PROBE); | |
229 | ||
90ccb6aa | 230 | ether_addr_copy(eah->hw_src, dev->dev_addr); |
1da177e4 LT |
231 | |
232 | eah->pa_src_zero = 0; | |
233 | eah->pa_src_net = us->s_net; | |
234 | eah->pa_src_node = us->s_node; | |
235 | ||
1a73de07 | 236 | eth_zero_addr(eah->hw_dst); |
1da177e4 LT |
237 | |
238 | eah->pa_dst_zero = 0; | |
239 | eah->pa_dst_net = us->s_net; | |
240 | eah->pa_dst_node = us->s_node; | |
241 | ||
242 | /* Send it */ | |
243 | aarp_dl->request(aarp_dl, skb, aarp_eth_multicast); | |
244 | } | |
245 | ||
246 | /* | |
247 | * Handle an aarp timer expire | |
248 | * | |
249 | * Must run under the aarp_lock. | |
250 | */ | |
251 | ||
252 | static void __aarp_expire_timer(struct aarp_entry **n) | |
253 | { | |
254 | struct aarp_entry *t; | |
255 | ||
256 | while (*n) | |
257 | /* Expired ? */ | |
258 | if (time_after(jiffies, (*n)->expires_at)) { | |
259 | t = *n; | |
260 | *n = (*n)->next; | |
261 | __aarp_expire(t); | |
262 | } else | |
263 | n = &((*n)->next); | |
264 | } | |
265 | ||
266 | /* | |
267 | * Kick all pending requests 5 times a second. | |
268 | * | |
269 | * Must run under the aarp_lock. | |
270 | */ | |
271 | static void __aarp_kick(struct aarp_entry **n) | |
272 | { | |
273 | struct aarp_entry *t; | |
274 | ||
275 | while (*n) | |
276 | /* Expired: if this will be the 11th tx, we delete instead. */ | |
277 | if ((*n)->xmit_count >= sysctl_aarp_retransmit_limit) { | |
278 | t = *n; | |
279 | *n = (*n)->next; | |
280 | __aarp_expire(t); | |
281 | } else { | |
282 | __aarp_send_query(*n); | |
283 | n = &((*n)->next); | |
284 | } | |
285 | } | |
286 | ||
287 | /* | |
288 | * A device has gone down. Take all entries referring to the device | |
289 | * and remove them. | |
290 | * | |
291 | * Must run under the aarp_lock. | |
292 | */ | |
293 | static void __aarp_expire_device(struct aarp_entry **n, struct net_device *dev) | |
294 | { | |
295 | struct aarp_entry *t; | |
296 | ||
297 | while (*n) | |
298 | if ((*n)->dev == dev) { | |
299 | t = *n; | |
300 | *n = (*n)->next; | |
301 | __aarp_expire(t); | |
302 | } else | |
303 | n = &((*n)->next); | |
304 | } | |
305 | ||
306 | /* Handle the timer event */ | |
e99e88a9 | 307 | static void aarp_expire_timeout(struct timer_list *unused) |
1da177e4 LT |
308 | { |
309 | int ct; | |
310 | ||
311 | write_lock_bh(&aarp_lock); | |
312 | ||
313 | for (ct = 0; ct < AARP_HASH_SIZE; ct++) { | |
314 | __aarp_expire_timer(&resolved[ct]); | |
315 | __aarp_kick(&unresolved[ct]); | |
316 | __aarp_expire_timer(&unresolved[ct]); | |
317 | __aarp_expire_timer(&proxies[ct]); | |
318 | } | |
319 | ||
320 | write_unlock_bh(&aarp_lock); | |
321 | mod_timer(&aarp_timer, jiffies + | |
322 | (unresolved_count ? sysctl_aarp_tick_time : | |
323 | sysctl_aarp_expiry_time)); | |
324 | } | |
325 | ||
326 | /* Network device notifier chain handler. */ | |
327 | static int aarp_device_event(struct notifier_block *this, unsigned long event, | |
328 | void *ptr) | |
329 | { | |
351638e7 | 330 | struct net_device *dev = netdev_notifier_info_to_dev(ptr); |
1da177e4 LT |
331 | int ct; |
332 | ||
721499e8 | 333 | if (!net_eq(dev_net(dev), &init_net)) |
e9dc8653 EB |
334 | return NOTIFY_DONE; |
335 | ||
1da177e4 LT |
336 | if (event == NETDEV_DOWN) { |
337 | write_lock_bh(&aarp_lock); | |
338 | ||
339 | for (ct = 0; ct < AARP_HASH_SIZE; ct++) { | |
890d52d3 EB |
340 | __aarp_expire_device(&resolved[ct], dev); |
341 | __aarp_expire_device(&unresolved[ct], dev); | |
342 | __aarp_expire_device(&proxies[ct], dev); | |
1da177e4 LT |
343 | } |
344 | ||
345 | write_unlock_bh(&aarp_lock); | |
346 | } | |
347 | return NOTIFY_DONE; | |
348 | } | |
349 | ||
350 | /* Expire all entries in a hash chain */ | |
351 | static void __aarp_expire_all(struct aarp_entry **n) | |
352 | { | |
353 | struct aarp_entry *t; | |
354 | ||
355 | while (*n) { | |
356 | t = *n; | |
357 | *n = (*n)->next; | |
358 | __aarp_expire(t); | |
359 | } | |
360 | } | |
361 | ||
362 | /* Cleanup all hash chains -- module unloading */ | |
363 | static void aarp_purge(void) | |
364 | { | |
365 | int ct; | |
366 | ||
367 | write_lock_bh(&aarp_lock); | |
368 | for (ct = 0; ct < AARP_HASH_SIZE; ct++) { | |
369 | __aarp_expire_all(&resolved[ct]); | |
370 | __aarp_expire_all(&unresolved[ct]); | |
371 | __aarp_expire_all(&proxies[ct]); | |
372 | } | |
373 | write_unlock_bh(&aarp_lock); | |
374 | } | |
375 | ||
376 | /* | |
377 | * Create a new aarp entry. This must use GFP_ATOMIC because it | |
378 | * runs while holding spinlocks. | |
379 | */ | |
380 | static struct aarp_entry *aarp_alloc(void) | |
381 | { | |
382 | struct aarp_entry *a = kmalloc(sizeof(*a), GFP_ATOMIC); | |
383 | ||
384 | if (a) | |
385 | skb_queue_head_init(&a->packet_queue); | |
386 | return a; | |
387 | } | |
388 | ||
389 | /* | |
390 | * Find an entry. We might return an expired but not yet purged entry. We | |
391 | * don't care as it will do no harm. | |
392 | * | |
393 | * This must run under the aarp_lock. | |
394 | */ | |
395 | static struct aarp_entry *__aarp_find_entry(struct aarp_entry *list, | |
396 | struct net_device *dev, | |
397 | struct atalk_addr *sat) | |
398 | { | |
399 | while (list) { | |
400 | if (list->target_addr.s_net == sat->s_net && | |
401 | list->target_addr.s_node == sat->s_node && | |
402 | list->dev == dev) | |
403 | break; | |
404 | list = list->next; | |
405 | } | |
406 | ||
407 | return list; | |
408 | } | |
409 | ||
410 | /* Called from the DDP code, and thus must be exported. */ | |
411 | void aarp_proxy_remove(struct net_device *dev, struct atalk_addr *sa) | |
412 | { | |
413 | int hash = sa->s_node % (AARP_HASH_SIZE - 1); | |
414 | struct aarp_entry *a; | |
415 | ||
416 | write_lock_bh(&aarp_lock); | |
417 | ||
418 | a = __aarp_find_entry(proxies[hash], dev, sa); | |
419 | if (a) | |
420 | a->expires_at = jiffies - 1; | |
421 | ||
422 | write_unlock_bh(&aarp_lock); | |
423 | } | |
424 | ||
425 | /* This must run under aarp_lock. */ | |
426 | static struct atalk_addr *__aarp_proxy_find(struct net_device *dev, | |
427 | struct atalk_addr *sa) | |
428 | { | |
429 | int hash = sa->s_node % (AARP_HASH_SIZE - 1); | |
430 | struct aarp_entry *a = __aarp_find_entry(proxies[hash], dev, sa); | |
431 | ||
432 | return a ? sa : NULL; | |
433 | } | |
434 | ||
435 | /* | |
436 | * Probe a Phase 1 device or a device that requires its Net:Node to | |
437 | * be set via an ioctl. | |
438 | */ | |
439 | static void aarp_send_probe_phase1(struct atalk_iface *iface) | |
440 | { | |
441 | struct ifreq atreq; | |
442 | struct sockaddr_at *sa = (struct sockaddr_at *)&atreq.ifr_addr; | |
03b35ccb | 443 | const struct net_device_ops *ops = iface->dev->netdev_ops; |
1da177e4 LT |
444 | |
445 | sa->sat_addr.s_node = iface->address.s_node; | |
446 | sa->sat_addr.s_net = ntohs(iface->address.s_net); | |
447 | ||
448 | /* We pass the Net:Node to the drivers/cards by a Device ioctl. */ | |
03b35ccb SH |
449 | if (!(ops->ndo_do_ioctl(iface->dev, &atreq, SIOCSIFADDR))) { |
450 | ops->ndo_do_ioctl(iface->dev, &atreq, SIOCGIFADDR); | |
1da177e4 LT |
451 | if (iface->address.s_net != htons(sa->sat_addr.s_net) || |
452 | iface->address.s_node != sa->sat_addr.s_node) | |
453 | iface->status |= ATIF_PROBE_FAIL; | |
454 | ||
455 | iface->address.s_net = htons(sa->sat_addr.s_net); | |
456 | iface->address.s_node = sa->sat_addr.s_node; | |
457 | } | |
458 | } | |
459 | ||
460 | ||
461 | void aarp_probe_network(struct atalk_iface *atif) | |
462 | { | |
463 | if (atif->dev->type == ARPHRD_LOCALTLK || | |
464 | atif->dev->type == ARPHRD_PPP) | |
465 | aarp_send_probe_phase1(atif); | |
466 | else { | |
467 | unsigned int count; | |
468 | ||
469 | for (count = 0; count < AARP_RETRANSMIT_LIMIT; count++) { | |
470 | aarp_send_probe(atif->dev, &atif->address); | |
471 | ||
472 | /* Defer 1/10th */ | |
285b3afe | 473 | msleep(100); |
1da177e4 LT |
474 | |
475 | if (atif->status & ATIF_PROBE_FAIL) | |
476 | break; | |
477 | } | |
478 | } | |
479 | } | |
480 | ||
481 | int aarp_proxy_probe_network(struct atalk_iface *atif, struct atalk_addr *sa) | |
482 | { | |
483 | int hash, retval = -EPROTONOSUPPORT; | |
484 | struct aarp_entry *entry; | |
485 | unsigned int count; | |
486 | ||
487 | /* | |
488 | * we don't currently support LocalTalk or PPP for proxy AARP; | |
489 | * if someone wants to try and add it, have fun | |
490 | */ | |
491 | if (atif->dev->type == ARPHRD_LOCALTLK || | |
492 | atif->dev->type == ARPHRD_PPP) | |
493 | goto out; | |
494 | ||
495 | /* | |
496 | * create a new AARP entry with the flags set to be published -- | |
497 | * we need this one to hang around even if it's in use | |
498 | */ | |
499 | entry = aarp_alloc(); | |
500 | retval = -ENOMEM; | |
501 | if (!entry) | |
502 | goto out; | |
503 | ||
504 | entry->expires_at = -1; | |
505 | entry->status = ATIF_PROBE; | |
506 | entry->target_addr.s_node = sa->s_node; | |
507 | entry->target_addr.s_net = sa->s_net; | |
508 | entry->dev = atif->dev; | |
509 | ||
510 | write_lock_bh(&aarp_lock); | |
511 | ||
512 | hash = sa->s_node % (AARP_HASH_SIZE - 1); | |
513 | entry->next = proxies[hash]; | |
514 | proxies[hash] = entry; | |
515 | ||
516 | for (count = 0; count < AARP_RETRANSMIT_LIMIT; count++) { | |
517 | aarp_send_probe(atif->dev, sa); | |
518 | ||
519 | /* Defer 1/10th */ | |
1da177e4 | 520 | write_unlock_bh(&aarp_lock); |
285b3afe | 521 | msleep(100); |
1da177e4 LT |
522 | write_lock_bh(&aarp_lock); |
523 | ||
524 | if (entry->status & ATIF_PROBE_FAIL) | |
525 | break; | |
526 | } | |
527 | ||
528 | if (entry->status & ATIF_PROBE_FAIL) { | |
529 | entry->expires_at = jiffies - 1; /* free the entry */ | |
530 | retval = -EADDRINUSE; /* return network full */ | |
531 | } else { /* clear the probing flag */ | |
532 | entry->status &= ~ATIF_PROBE; | |
533 | retval = 1; | |
534 | } | |
535 | ||
536 | write_unlock_bh(&aarp_lock); | |
537 | out: | |
538 | return retval; | |
539 | } | |
540 | ||
541 | /* Send a DDP frame */ | |
542 | int aarp_send_ddp(struct net_device *dev, struct sk_buff *skb, | |
543 | struct atalk_addr *sa, void *hwaddr) | |
544 | { | |
545 | static char ddp_eth_multicast[ETH_ALEN] = | |
546 | { 0x09, 0x00, 0x07, 0xFF, 0xFF, 0xFF }; | |
547 | int hash; | |
548 | struct aarp_entry *a; | |
549 | ||
c1d2bbe1 | 550 | skb_reset_network_header(skb); |
1da177e4 LT |
551 | |
552 | /* Check for LocalTalk first */ | |
553 | if (dev->type == ARPHRD_LOCALTLK) { | |
554 | struct atalk_addr *at = atalk_find_dev_addr(dev); | |
555 | struct ddpehdr *ddp = (struct ddpehdr *)skb->data; | |
556 | int ft = 2; | |
557 | ||
558 | /* | |
559 | * Compressible ? | |
560 | * | |
561 | * IFF: src_net == dest_net == device_net | |
562 | * (zero matches anything) | |
563 | */ | |
564 | ||
565 | if ((!ddp->deh_snet || at->s_net == ddp->deh_snet) && | |
566 | (!ddp->deh_dnet || at->s_net == ddp->deh_dnet)) { | |
567 | skb_pull(skb, sizeof(*ddp) - 4); | |
568 | ||
569 | /* | |
570 | * The upper two remaining bytes are the port | |
571 | * numbers we just happen to need. Now put the | |
572 | * length in the lower two. | |
573 | */ | |
f6e276ee | 574 | *((__be16 *)skb->data) = htons(skb->len); |
1da177e4 LT |
575 | ft = 1; |
576 | } | |
577 | /* | |
578 | * Nice and easy. No AARP type protocols occur here so we can | |
579 | * just shovel it out with a 3 byte LLAP header | |
580 | */ | |
581 | ||
582 | skb_push(skb, 3); | |
583 | skb->data[0] = sa->s_node; | |
584 | skb->data[1] = at->s_node; | |
585 | skb->data[2] = ft; | |
586 | skb->dev = dev; | |
587 | goto sendit; | |
588 | } | |
589 | ||
590 | /* On a PPP link we neither compress nor aarp. */ | |
591 | if (dev->type == ARPHRD_PPP) { | |
592 | skb->protocol = htons(ETH_P_PPPTALK); | |
593 | skb->dev = dev; | |
594 | goto sendit; | |
595 | } | |
596 | ||
597 | /* Non ELAP we cannot do. */ | |
598 | if (dev->type != ARPHRD_ETHER) | |
ffcfb8db | 599 | goto free_it; |
1da177e4 LT |
600 | |
601 | skb->dev = dev; | |
602 | skb->protocol = htons(ETH_P_ATALK); | |
603 | hash = sa->s_node % (AARP_HASH_SIZE - 1); | |
604 | ||
605 | /* Do we have a resolved entry? */ | |
606 | if (sa->s_node == ATADDR_BCAST) { | |
607 | /* Send it */ | |
608 | ddp_dl->request(ddp_dl, skb, ddp_eth_multicast); | |
609 | goto sent; | |
610 | } | |
611 | ||
612 | write_lock_bh(&aarp_lock); | |
613 | a = __aarp_find_entry(resolved[hash], dev, sa); | |
614 | ||
615 | if (a) { /* Return 1 and fill in the address */ | |
616 | a->expires_at = jiffies + (sysctl_aarp_expiry_time * 10); | |
617 | ddp_dl->request(ddp_dl, skb, a->hwaddr); | |
618 | write_unlock_bh(&aarp_lock); | |
619 | goto sent; | |
620 | } | |
621 | ||
622 | /* Do we have an unresolved entry: This is the less common path */ | |
623 | a = __aarp_find_entry(unresolved[hash], dev, sa); | |
624 | if (a) { /* Queue onto the unresolved queue */ | |
625 | skb_queue_tail(&a->packet_queue, skb); | |
626 | goto out_unlock; | |
627 | } | |
628 | ||
629 | /* Allocate a new entry */ | |
630 | a = aarp_alloc(); | |
631 | if (!a) { | |
632 | /* Whoops slipped... good job it's an unreliable protocol 8) */ | |
633 | write_unlock_bh(&aarp_lock); | |
ffcfb8db | 634 | goto free_it; |
1da177e4 LT |
635 | } |
636 | ||
637 | /* Set up the queue */ | |
638 | skb_queue_tail(&a->packet_queue, skb); | |
639 | a->expires_at = jiffies + sysctl_aarp_resolve_time; | |
640 | a->dev = dev; | |
641 | a->next = unresolved[hash]; | |
642 | a->target_addr = *sa; | |
643 | a->xmit_count = 0; | |
644 | unresolved[hash] = a; | |
645 | unresolved_count++; | |
646 | ||
647 | /* Send an initial request for the address */ | |
648 | __aarp_send_query(a); | |
649 | ||
650 | /* | |
651 | * Switch to fast timer if needed (That is if this is the first | |
652 | * unresolved entry to get added) | |
653 | */ | |
654 | ||
655 | if (unresolved_count == 1) | |
656 | mod_timer(&aarp_timer, jiffies + sysctl_aarp_tick_time); | |
657 | ||
658 | /* Now finally, it is safe to drop the lock. */ | |
659 | out_unlock: | |
660 | write_unlock_bh(&aarp_lock); | |
661 | ||
662 | /* Tell the ddp layer we have taken over for this frame. */ | |
ffcfb8db | 663 | goto sent; |
1da177e4 LT |
664 | |
665 | sendit: | |
666 | if (skb->sk) | |
667 | skb->priority = skb->sk->sk_priority; | |
ffcfb8db ACM |
668 | if (dev_queue_xmit(skb)) |
669 | goto drop; | |
1da177e4 | 670 | sent: |
ffcfb8db ACM |
671 | return NET_XMIT_SUCCESS; |
672 | free_it: | |
673 | kfree_skb(skb); | |
674 | drop: | |
675 | return NET_XMIT_DROP; | |
1da177e4 | 676 | } |
ffcfb8db | 677 | EXPORT_SYMBOL(aarp_send_ddp); |
1da177e4 LT |
678 | |
679 | /* | |
680 | * An entry in the aarp unresolved queue has become resolved. Send | |
681 | * all the frames queued under it. | |
682 | * | |
683 | * Must run under aarp_lock. | |
684 | */ | |
685 | static void __aarp_resolved(struct aarp_entry **list, struct aarp_entry *a, | |
686 | int hash) | |
687 | { | |
688 | struct sk_buff *skb; | |
689 | ||
690 | while (*list) | |
691 | if (*list == a) { | |
692 | unresolved_count--; | |
693 | *list = a->next; | |
694 | ||
695 | /* Move into the resolved list */ | |
696 | a->next = resolved[hash]; | |
697 | resolved[hash] = a; | |
698 | ||
699 | /* Kick frames off */ | |
700 | while ((skb = skb_dequeue(&a->packet_queue)) != NULL) { | |
701 | a->expires_at = jiffies + | |
702 | sysctl_aarp_expiry_time * 10; | |
703 | ddp_dl->request(ddp_dl, skb, a->hwaddr); | |
704 | } | |
705 | } else | |
706 | list = &((*list)->next); | |
707 | } | |
708 | ||
709 | /* | |
710 | * This is called by the SNAP driver whenever we see an AARP SNAP | |
711 | * frame. We currently only support Ethernet. | |
712 | */ | |
713 | static int aarp_rcv(struct sk_buff *skb, struct net_device *dev, | |
f2ccd8fa | 714 | struct packet_type *pt, struct net_device *orig_dev) |
1da177e4 LT |
715 | { |
716 | struct elapaarp *ea = aarp_hdr(skb); | |
717 | int hash, ret = 0; | |
718 | __u16 function; | |
719 | struct aarp_entry *a; | |
720 | struct atalk_addr sa, *ma, da; | |
721 | struct atalk_iface *ifa; | |
722 | ||
721499e8 | 723 | if (!net_eq(dev_net(dev), &init_net)) |
e730c155 EB |
724 | goto out0; |
725 | ||
1da177e4 LT |
726 | /* We only do Ethernet SNAP AARP. */ |
727 | if (dev->type != ARPHRD_ETHER) | |
728 | goto out0; | |
729 | ||
730 | /* Frame size ok? */ | |
731 | if (!skb_pull(skb, sizeof(*ea))) | |
732 | goto out0; | |
733 | ||
734 | function = ntohs(ea->function); | |
735 | ||
736 | /* Sanity check fields. */ | |
737 | if (function < AARP_REQUEST || function > AARP_PROBE || | |
738 | ea->hw_len != ETH_ALEN || ea->pa_len != AARP_PA_ALEN || | |
739 | ea->pa_src_zero || ea->pa_dst_zero) | |
740 | goto out0; | |
741 | ||
742 | /* Looks good. */ | |
743 | hash = ea->pa_src_node % (AARP_HASH_SIZE - 1); | |
744 | ||
745 | /* Build an address. */ | |
746 | sa.s_node = ea->pa_src_node; | |
747 | sa.s_net = ea->pa_src_net; | |
748 | ||
749 | /* Process the packet. Check for replies of me. */ | |
750 | ifa = atalk_find_dev(dev); | |
751 | if (!ifa) | |
752 | goto out1; | |
753 | ||
754 | if (ifa->status & ATIF_PROBE && | |
755 | ifa->address.s_node == ea->pa_dst_node && | |
756 | ifa->address.s_net == ea->pa_dst_net) { | |
757 | ifa->status |= ATIF_PROBE_FAIL; /* Fail the probe (in use) */ | |
758 | goto out1; | |
759 | } | |
760 | ||
761 | /* Check for replies of proxy AARP entries */ | |
762 | da.s_node = ea->pa_dst_node; | |
763 | da.s_net = ea->pa_dst_net; | |
764 | ||
765 | write_lock_bh(&aarp_lock); | |
766 | a = __aarp_find_entry(proxies[hash], dev, &da); | |
767 | ||
768 | if (a && a->status & ATIF_PROBE) { | |
769 | a->status |= ATIF_PROBE_FAIL; | |
770 | /* | |
d439aa33 | 771 | * we do not respond to probe or request packets of |
1da177e4 LT |
772 | * this address while we are probing this address |
773 | */ | |
774 | goto unlock; | |
775 | } | |
776 | ||
777 | switch (function) { | |
4a9e4b09 JP |
778 | case AARP_REPLY: |
779 | if (!unresolved_count) /* Speed up */ | |
780 | break; | |
1da177e4 | 781 | |
4a9e4b09 JP |
782 | /* Find the entry. */ |
783 | a = __aarp_find_entry(unresolved[hash], dev, &sa); | |
784 | if (!a || dev != a->dev) | |
1da177e4 LT |
785 | break; |
786 | ||
4a9e4b09 | 787 | /* We can fill one in - this is good. */ |
90ccb6aa | 788 | ether_addr_copy(a->hwaddr, ea->hw_src); |
4a9e4b09 JP |
789 | __aarp_resolved(&unresolved[hash], a, hash); |
790 | if (!unresolved_count) | |
791 | mod_timer(&aarp_timer, | |
792 | jiffies + sysctl_aarp_expiry_time); | |
793 | break; | |
794 | ||
795 | case AARP_REQUEST: | |
796 | case AARP_PROBE: | |
797 | ||
798 | /* | |
799 | * If it is my address set ma to my address and reply. | |
800 | * We can treat probe and request the same. Probe | |
801 | * simply means we shouldn't cache the querying host, | |
802 | * as in a probe they are proposing an address not | |
803 | * using one. | |
804 | * | |
805 | * Support for proxy-AARP added. We check if the | |
806 | * address is one of our proxies before we toss the | |
807 | * packet out. | |
808 | */ | |
809 | ||
810 | sa.s_node = ea->pa_dst_node; | |
811 | sa.s_net = ea->pa_dst_net; | |
812 | ||
813 | /* See if we have a matching proxy. */ | |
814 | ma = __aarp_proxy_find(dev, &sa); | |
815 | if (!ma) | |
816 | ma = &ifa->address; | |
817 | else { /* We need to make a copy of the entry. */ | |
818 | da.s_node = sa.s_node; | |
819 | da.s_net = sa.s_net; | |
820 | ma = &da; | |
821 | } | |
1da177e4 | 822 | |
4a9e4b09 | 823 | if (function == AARP_PROBE) { |
1da177e4 | 824 | /* |
4a9e4b09 JP |
825 | * A probe implies someone trying to get an |
826 | * address. So as a precaution flush any | |
827 | * entries we have for this address. | |
1da177e4 | 828 | */ |
4a9e4b09 JP |
829 | a = __aarp_find_entry(resolved[sa.s_node % |
830 | (AARP_HASH_SIZE - 1)], | |
831 | skb->dev, &sa); | |
1da177e4 | 832 | |
4a9e4b09 JP |
833 | /* |
834 | * Make it expire next tick - that avoids us | |
835 | * getting into a probe/flush/learn/probe/ | |
836 | * flush/learn cycle during probing of a slow | |
837 | * to respond host addr. | |
838 | */ | |
839 | if (a) { | |
840 | a->expires_at = jiffies - 1; | |
841 | mod_timer(&aarp_timer, jiffies + | |
842 | sysctl_aarp_tick_time); | |
1da177e4 | 843 | } |
4a9e4b09 | 844 | } |
1da177e4 | 845 | |
4a9e4b09 JP |
846 | if (sa.s_node != ma->s_node) |
847 | break; | |
1da177e4 | 848 | |
4a9e4b09 JP |
849 | if (sa.s_net && ma->s_net && sa.s_net != ma->s_net) |
850 | break; | |
1da177e4 | 851 | |
4a9e4b09 JP |
852 | sa.s_node = ea->pa_src_node; |
853 | sa.s_net = ea->pa_src_net; | |
1da177e4 | 854 | |
4a9e4b09 JP |
855 | /* aarp_my_address has found the address to use for us. |
856 | */ | |
857 | aarp_send_reply(dev, ma, &sa, ea->hw_src); | |
858 | break; | |
1da177e4 LT |
859 | } |
860 | ||
861 | unlock: | |
862 | write_unlock_bh(&aarp_lock); | |
863 | out1: | |
864 | ret = 1; | |
865 | out0: | |
866 | kfree_skb(skb); | |
867 | return ret; | |
868 | } | |
869 | ||
870 | static struct notifier_block aarp_notifier = { | |
871 | .notifier_call = aarp_device_event, | |
872 | }; | |
873 | ||
874 | static unsigned char aarp_snap_id[] = { 0x00, 0x00, 0x00, 0x80, 0xF3 }; | |
875 | ||
9804501f | 876 | int __init aarp_proto_init(void) |
1da177e4 | 877 | { |
9804501f Y |
878 | int rc; |
879 | ||
1da177e4 | 880 | aarp_dl = register_snap_client(aarp_snap_id, aarp_rcv); |
9804501f | 881 | if (!aarp_dl) { |
1da177e4 | 882 | printk(KERN_CRIT "Unable to register AARP with SNAP.\n"); |
9804501f Y |
883 | return -ENOMEM; |
884 | } | |
e99e88a9 | 885 | timer_setup(&aarp_timer, aarp_expire_timeout, 0); |
1da177e4 LT |
886 | aarp_timer.expires = jiffies + sysctl_aarp_expiry_time; |
887 | add_timer(&aarp_timer); | |
9804501f Y |
888 | rc = register_netdevice_notifier(&aarp_notifier); |
889 | if (rc) { | |
890 | del_timer_sync(&aarp_timer); | |
891 | unregister_snap_client(aarp_dl); | |
892 | } | |
893 | return rc; | |
1da177e4 LT |
894 | } |
895 | ||
896 | /* Remove the AARP entries associated with a device. */ | |
897 | void aarp_device_down(struct net_device *dev) | |
898 | { | |
899 | int ct; | |
900 | ||
901 | write_lock_bh(&aarp_lock); | |
902 | ||
903 | for (ct = 0; ct < AARP_HASH_SIZE; ct++) { | |
904 | __aarp_expire_device(&resolved[ct], dev); | |
905 | __aarp_expire_device(&unresolved[ct], dev); | |
906 | __aarp_expire_device(&proxies[ct], dev); | |
907 | } | |
908 | ||
909 | write_unlock_bh(&aarp_lock); | |
910 | } | |
911 | ||
912 | #ifdef CONFIG_PROC_FS | |
1da177e4 LT |
913 | /* |
914 | * Get the aarp entry that is in the chain described | |
ed4477b9 | 915 | * by the iterator. |
1da177e4 LT |
916 | * If pos is set then skip till that index. |
917 | * pos = 1 is the first entry | |
918 | */ | |
919 | static struct aarp_entry *iter_next(struct aarp_iter_state *iter, loff_t *pos) | |
920 | { | |
921 | int ct = iter->bucket; | |
922 | struct aarp_entry **table = iter->table; | |
923 | loff_t off = 0; | |
924 | struct aarp_entry *entry; | |
ed4477b9 | 925 | |
1da177e4 | 926 | rescan: |
fd1dc261 | 927 | while (ct < AARP_HASH_SIZE) { |
1da177e4 LT |
928 | for (entry = table[ct]; entry; entry = entry->next) { |
929 | if (!pos || ++off == *pos) { | |
930 | iter->table = table; | |
931 | iter->bucket = ct; | |
932 | return entry; | |
933 | } | |
934 | } | |
935 | ++ct; | |
936 | } | |
937 | ||
938 | if (table == resolved) { | |
939 | ct = 0; | |
940 | table = unresolved; | |
941 | goto rescan; | |
942 | } | |
943 | if (table == unresolved) { | |
944 | ct = 0; | |
945 | table = proxies; | |
946 | goto rescan; | |
947 | } | |
948 | return NULL; | |
949 | } | |
950 | ||
951 | static void *aarp_seq_start(struct seq_file *seq, loff_t *pos) | |
ca629f24 | 952 | __acquires(aarp_lock) |
1da177e4 LT |
953 | { |
954 | struct aarp_iter_state *iter = seq->private; | |
955 | ||
956 | read_lock_bh(&aarp_lock); | |
957 | iter->table = resolved; | |
958 | iter->bucket = 0; | |
959 | ||
960 | return *pos ? iter_next(iter, pos) : SEQ_START_TOKEN; | |
961 | } | |
962 | ||
963 | static void *aarp_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
964 | { | |
965 | struct aarp_entry *entry = v; | |
966 | struct aarp_iter_state *iter = seq->private; | |
967 | ||
968 | ++*pos; | |
969 | ||
970 | /* first line after header */ | |
ed4477b9 | 971 | if (v == SEQ_START_TOKEN) |
1da177e4 | 972 | entry = iter_next(iter, NULL); |
ed4477b9 | 973 | |
1da177e4 LT |
974 | /* next entry in current bucket */ |
975 | else if (entry->next) | |
976 | entry = entry->next; | |
977 | ||
978 | /* next bucket or table */ | |
979 | else { | |
980 | ++iter->bucket; | |
981 | entry = iter_next(iter, NULL); | |
982 | } | |
983 | return entry; | |
984 | } | |
985 | ||
986 | static void aarp_seq_stop(struct seq_file *seq, void *v) | |
ca629f24 | 987 | __releases(aarp_lock) |
1da177e4 LT |
988 | { |
989 | read_unlock_bh(&aarp_lock); | |
990 | } | |
991 | ||
992 | static const char *dt2str(unsigned long ticks) | |
993 | { | |
994 | static char buf[32]; | |
995 | ||
fd1dc261 | 996 | sprintf(buf, "%ld.%02ld", ticks / HZ, ((ticks % HZ) * 100) / HZ); |
1da177e4 LT |
997 | |
998 | return buf; | |
999 | } | |
1000 | ||
1001 | static int aarp_seq_show(struct seq_file *seq, void *v) | |
1002 | { | |
1003 | struct aarp_iter_state *iter = seq->private; | |
1004 | struct aarp_entry *entry = v; | |
1005 | unsigned long now = jiffies; | |
1006 | ||
1007 | if (v == SEQ_START_TOKEN) | |
ed4477b9 | 1008 | seq_puts(seq, |
1da177e4 LT |
1009 | "Address Interface Hardware Address" |
1010 | " Expires LastSend Retry Status\n"); | |
1011 | else { | |
1012 | seq_printf(seq, "%04X:%02X %-12s", | |
1013 | ntohs(entry->target_addr.s_net), | |
1014 | (unsigned int) entry->target_addr.s_node, | |
1015 | entry->dev ? entry->dev->name : "????"); | |
e174961c | 1016 | seq_printf(seq, "%pM", entry->hwaddr); |
1da177e4 LT |
1017 | seq_printf(seq, " %8s", |
1018 | dt2str((long)entry->expires_at - (long)now)); | |
1019 | if (iter->table == unresolved) | |
1020 | seq_printf(seq, " %8s %6hu", | |
1021 | dt2str(now - entry->last_sent), | |
1022 | entry->xmit_count); | |
1023 | else | |
1024 | seq_puts(seq, " "); | |
1025 | seq_printf(seq, " %s\n", | |
1026 | (iter->table == resolved) ? "resolved" | |
1027 | : (iter->table == unresolved) ? "unresolved" | |
1028 | : (iter->table == proxies) ? "proxies" | |
1029 | : "unknown"); | |
ed4477b9 | 1030 | } |
1da177e4 LT |
1031 | return 0; |
1032 | } | |
1033 | ||
44414d82 | 1034 | const struct seq_operations aarp_seq_ops = { |
1da177e4 LT |
1035 | .start = aarp_seq_start, |
1036 | .next = aarp_seq_next, | |
1037 | .stop = aarp_seq_stop, | |
1038 | .show = aarp_seq_show, | |
1039 | }; | |
1da177e4 LT |
1040 | #endif |
1041 | ||
1042 | /* General module cleanup. Called from cleanup_module() in ddp.c. */ | |
1043 | void aarp_cleanup_module(void) | |
1044 | { | |
1045 | del_timer_sync(&aarp_timer); | |
1046 | unregister_netdevice_notifier(&aarp_notifier); | |
1047 | unregister_snap_client(aarp_dl); | |
1048 | aarp_purge(); | |
1049 | } |