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-rw-r--r--net/802/garp.c633
1 files changed, 633 insertions, 0 deletions
diff --git a/net/802/garp.c b/net/802/garp.c
new file mode 100644
index 000000000000..3b78f7b74fd4
--- /dev/null
+++ b/net/802/garp.c
@@ -0,0 +1,633 @@
1/*
2 * IEEE 802.1D Generic Attribute Registration Protocol (GARP)
3 *
4 * Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * version 2 as published by the Free Software Foundation.
9 */
10#include <linux/kernel.h>
11#include <linux/timer.h>
12#include <linux/skbuff.h>
13#include <linux/netdevice.h>
14#include <linux/etherdevice.h>
15#include <linux/rtnetlink.h>
16#include <linux/llc.h>
17#include <net/llc.h>
18#include <net/llc_pdu.h>
19#include <net/garp.h>
20#include <asm/unaligned.h>
21
22static unsigned int garp_join_time __read_mostly = 200;
23module_param(garp_join_time, uint, 0644);
24MODULE_PARM_DESC(garp_join_time, "Join time in ms (default 200ms)");
25MODULE_LICENSE("GPL");
26
27static const struct garp_state_trans {
28 u8 state;
29 u8 action;
30} garp_applicant_state_table[GARP_APPLICANT_MAX + 1][GARP_EVENT_MAX + 1] = {
31 [GARP_APPLICANT_VA] = {
32 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_AA,
33 .action = GARP_ACTION_S_JOIN_IN },
34 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AA },
35 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
36 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
37 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VA },
38 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
39 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
40 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
41 },
42 [GARP_APPLICANT_AA] = {
43 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_QA,
44 .action = GARP_ACTION_S_JOIN_IN },
45 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QA },
46 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
47 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
48 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VA },
49 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
50 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
51 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
52 },
53 [GARP_APPLICANT_QA] = {
54 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
55 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QA },
56 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
57 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
58 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
59 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
60 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
61 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
62 },
63 [GARP_APPLICANT_LA] = {
64 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_VO,
65 .action = GARP_ACTION_S_LEAVE_EMPTY },
66 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_LA },
67 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
68 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_LA },
69 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_LA },
70 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
71 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_VA },
72 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
73 },
74 [GARP_APPLICANT_VP] = {
75 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_AA,
76 .action = GARP_ACTION_S_JOIN_IN },
77 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AP },
78 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
79 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
80 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
81 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
82 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
83 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_VO },
84 },
85 [GARP_APPLICANT_AP] = {
86 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_QA,
87 .action = GARP_ACTION_S_JOIN_IN },
88 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QP },
89 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
90 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
91 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
92 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
93 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
94 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_AO },
95 },
96 [GARP_APPLICANT_QP] = {
97 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
98 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QP },
99 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
100 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
101 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
102 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
103 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
104 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_QO },
105 },
106 [GARP_APPLICANT_VO] = {
107 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
108 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AO },
109 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
110 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
111 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
112 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
113 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_VP },
114 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
115 },
116 [GARP_APPLICANT_AO] = {
117 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
118 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO },
119 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
120 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
121 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
122 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
123 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_AP },
124 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
125 },
126 [GARP_APPLICANT_QO] = {
127 [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
128 [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO },
129 [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
130 [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
131 [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
132 [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
133 [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_QP },
134 [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
135 },
136};
137
138static int garp_attr_cmp(const struct garp_attr *attr,
139 const void *data, u8 len, u8 type)
140{
141 if (attr->type != type)
142 return attr->type - type;
143 if (attr->dlen != len)
144 return attr->dlen - len;
145 return memcmp(attr->data, data, len);
146}
147
148static struct garp_attr *garp_attr_lookup(const struct garp_applicant *app,
149 const void *data, u8 len, u8 type)
150{
151 struct rb_node *parent = app->gid.rb_node;
152 struct garp_attr *attr;
153 int d;
154
155 while (parent) {
156 attr = rb_entry(parent, struct garp_attr, node);
157 d = garp_attr_cmp(attr, data, len, type);
158 if (d < 0)
159 parent = parent->rb_left;
160 else if (d > 0)
161 parent = parent->rb_right;
162 else
163 return attr;
164 }
165 return NULL;
166}
167
168static void garp_attr_insert(struct garp_applicant *app, struct garp_attr *new)
169{
170 struct rb_node *parent = NULL, **p = &app->gid.rb_node;
171 struct garp_attr *attr;
172 int d;
173
174 while (*p) {
175 parent = *p;
176 attr = rb_entry(parent, struct garp_attr, node);
177 d = garp_attr_cmp(attr, new->data, new->dlen, new->type);
178 if (d < 0)
179 p = &parent->rb_left;
180 else if (d > 0)
181 p = &parent->rb_right;
182 }
183 rb_link_node(&new->node, parent, p);
184 rb_insert_color(&new->node, &app->gid);
185}
186
187static struct garp_attr *garp_attr_create(struct garp_applicant *app,
188 const void *data, u8 len, u8 type)
189{
190 struct garp_attr *attr;
191
192 attr = kmalloc(sizeof(*attr) + len, GFP_ATOMIC);
193 if (!attr)
194 return attr;
195 attr->state = GARP_APPLICANT_VO;
196 attr->type = type;
197 attr->dlen = len;
198 memcpy(attr->data, data, len);
199 garp_attr_insert(app, attr);
200 return attr;
201}
202
203static void garp_attr_destroy(struct garp_applicant *app, struct garp_attr *attr)
204{
205 rb_erase(&attr->node, &app->gid);
206 kfree(attr);
207}
208
209static int garp_pdu_init(struct garp_applicant *app)
210{
211 struct sk_buff *skb;
212 struct garp_pdu_hdr *gp;
213
214#define LLC_RESERVE sizeof(struct llc_pdu_un)
215 skb = alloc_skb(app->dev->mtu + LL_RESERVED_SPACE(app->dev),
216 GFP_ATOMIC);
217 if (!skb)
218 return -ENOMEM;
219
220 skb->dev = app->dev;
221 skb->protocol = htons(ETH_P_802_2);
222 skb_reserve(skb, LL_RESERVED_SPACE(app->dev) + LLC_RESERVE);
223
224 gp = (struct garp_pdu_hdr *)__skb_put(skb, sizeof(*gp));
225 put_unaligned(htons(GARP_PROTOCOL_ID), &gp->protocol);
226
227 app->pdu = skb;
228 return 0;
229}
230
231static int garp_pdu_append_end_mark(struct garp_applicant *app)
232{
233 if (skb_tailroom(app->pdu) < sizeof(u8))
234 return -1;
235 *(u8 *)__skb_put(app->pdu, sizeof(u8)) = GARP_END_MARK;
236 return 0;
237}
238
239static void garp_pdu_queue(struct garp_applicant *app)
240{
241 if (!app->pdu)
242 return;
243
244 garp_pdu_append_end_mark(app);
245 garp_pdu_append_end_mark(app);
246
247 llc_pdu_header_init(app->pdu, LLC_PDU_TYPE_U, LLC_SAP_BSPAN,
248 LLC_SAP_BSPAN, LLC_PDU_CMD);
249 llc_pdu_init_as_ui_cmd(app->pdu);
250 llc_mac_hdr_init(app->pdu, app->dev->dev_addr,
251 app->app->proto.group_address);
252
253 skb_queue_tail(&app->queue, app->pdu);
254 app->pdu = NULL;
255}
256
257static void garp_queue_xmit(struct garp_applicant *app)
258{
259 struct sk_buff *skb;
260
261 while ((skb = skb_dequeue(&app->queue)))
262 dev_queue_xmit(skb);
263}
264
265static int garp_pdu_append_msg(struct garp_applicant *app, u8 attrtype)
266{
267 struct garp_msg_hdr *gm;
268
269 if (skb_tailroom(app->pdu) < sizeof(*gm))
270 return -1;
271 gm = (struct garp_msg_hdr *)__skb_put(app->pdu, sizeof(*gm));
272 gm->attrtype = attrtype;
273 garp_cb(app->pdu)->cur_type = attrtype;
274 return 0;
275}
276
277static int garp_pdu_append_attr(struct garp_applicant *app,
278 const struct garp_attr *attr,
279 enum garp_attr_event event)
280{
281 struct garp_attr_hdr *ga;
282 unsigned int len;
283 int err;
284again:
285 if (!app->pdu) {
286 err = garp_pdu_init(app);
287 if (err < 0)
288 return err;
289 }
290
291 if (garp_cb(app->pdu)->cur_type != attr->type) {
292 if (garp_cb(app->pdu)->cur_type &&
293 garp_pdu_append_end_mark(app) < 0)
294 goto queue;
295 if (garp_pdu_append_msg(app, attr->type) < 0)
296 goto queue;
297 }
298
299 len = sizeof(*ga) + attr->dlen;
300 if (skb_tailroom(app->pdu) < len)
301 goto queue;
302 ga = (struct garp_attr_hdr *)__skb_put(app->pdu, len);
303 ga->len = len;
304 ga->event = event;
305 memcpy(ga->data, attr->data, attr->dlen);
306 return 0;
307
308queue:
309 garp_pdu_queue(app);
310 goto again;
311}
312
313static void garp_attr_event(struct garp_applicant *app,
314 struct garp_attr *attr, enum garp_event event)
315{
316 enum garp_applicant_state state;
317
318 state = garp_applicant_state_table[attr->state][event].state;
319 if (state == GARP_APPLICANT_INVALID)
320 return;
321
322 switch (garp_applicant_state_table[attr->state][event].action) {
323 case GARP_ACTION_NONE:
324 break;
325 case GARP_ACTION_S_JOIN_IN:
326 garp_pdu_append_attr(app, attr, GARP_JOIN_IN);
327 break;
328 case GARP_ACTION_S_LEAVE_EMPTY:
329 garp_pdu_append_attr(app, attr, GARP_LEAVE_EMPTY);
330 /* As a pure applicant, sending a leave message implies that
331 * the attribute was unregistered and can be destroyed. */
332 garp_attr_destroy(app, attr);
333 return;
334 default:
335 WARN_ON(1);
336 }
337
338 attr->state = state;
339}
340
341int garp_request_join(const struct net_device *dev,
342 const struct garp_application *appl,
343 const void *data, u8 len, u8 type)
344{
345 struct garp_port *port = dev->garp_port;
346 struct garp_applicant *app = port->applicants[appl->type];
347 struct garp_attr *attr;
348
349 spin_lock_bh(&app->lock);
350 attr = garp_attr_create(app, data, len, type);
351 if (!attr) {
352 spin_unlock_bh(&app->lock);
353 return -ENOMEM;
354 }
355 garp_attr_event(app, attr, GARP_EVENT_REQ_JOIN);
356 spin_unlock_bh(&app->lock);
357 return 0;
358}
359EXPORT_SYMBOL_GPL(garp_request_join);
360
361void garp_request_leave(const struct net_device *dev,
362 const struct garp_application *appl,
363 const void *data, u8 len, u8 type)
364{
365 struct garp_port *port = dev->garp_port;
366 struct garp_applicant *app = port->applicants[appl->type];
367 struct garp_attr *attr;
368
369 spin_lock_bh(&app->lock);
370 attr = garp_attr_lookup(app, data, len, type);
371 if (!attr) {
372 spin_unlock_bh(&app->lock);
373 return;
374 }
375 garp_attr_event(app, attr, GARP_EVENT_REQ_LEAVE);
376 spin_unlock_bh(&app->lock);
377}
378EXPORT_SYMBOL_GPL(garp_request_leave);
379
380static void garp_gid_event(struct garp_applicant *app, enum garp_event event)
381{
382 struct rb_node *node, *next;
383 struct garp_attr *attr;
384
385 for (node = rb_first(&app->gid);
386 next = node ? rb_next(node) : NULL, node != NULL;
387 node = next) {
388 attr = rb_entry(node, struct garp_attr, node);
389 garp_attr_event(app, attr, event);
390 }
391}
392
393static void garp_join_timer_arm(struct garp_applicant *app)
394{
395 unsigned long delay;
396
397 delay = (u64)msecs_to_jiffies(garp_join_time) * net_random() >> 32;
398 mod_timer(&app->join_timer, jiffies + delay);
399}
400
401static void garp_join_timer(unsigned long data)
402{
403 struct garp_applicant *app = (struct garp_applicant *)data;
404
405 spin_lock(&app->lock);
406 garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU);
407 garp_pdu_queue(app);
408 spin_unlock(&app->lock);
409
410 garp_queue_xmit(app);
411 garp_join_timer_arm(app);
412}
413
414static int garp_pdu_parse_end_mark(struct sk_buff *skb)
415{
416 if (!pskb_may_pull(skb, sizeof(u8)))
417 return -1;
418 if (*skb->data == GARP_END_MARK) {
419 skb_pull(skb, sizeof(u8));
420 return -1;
421 }
422 return 0;
423}
424
425static int garp_pdu_parse_attr(struct garp_applicant *app, struct sk_buff *skb,
426 u8 attrtype)
427{
428 const struct garp_attr_hdr *ga;
429 struct garp_attr *attr;
430 enum garp_event event;
431 unsigned int dlen;
432
433 if (!pskb_may_pull(skb, sizeof(*ga)))
434 return -1;
435 ga = (struct garp_attr_hdr *)skb->data;
436 if (ga->len < sizeof(*ga))
437 return -1;
438
439 if (!pskb_may_pull(skb, ga->len))
440 return -1;
441 skb_pull(skb, ga->len);
442 dlen = sizeof(*ga) - ga->len;
443
444 if (attrtype > app->app->maxattr)
445 return 0;
446
447 switch (ga->event) {
448 case GARP_LEAVE_ALL:
449 if (dlen != 0)
450 return -1;
451 garp_gid_event(app, GARP_EVENT_R_LEAVE_EMPTY);
452 return 0;
453 case GARP_JOIN_EMPTY:
454 event = GARP_EVENT_R_JOIN_EMPTY;
455 break;
456 case GARP_JOIN_IN:
457 event = GARP_EVENT_R_JOIN_IN;
458 break;
459 case GARP_LEAVE_EMPTY:
460 event = GARP_EVENT_R_LEAVE_EMPTY;
461 break;
462 case GARP_EMPTY:
463 event = GARP_EVENT_R_EMPTY;
464 break;
465 default:
466 return 0;
467 }
468
469 if (dlen == 0)
470 return -1;
471 attr = garp_attr_lookup(app, ga->data, dlen, attrtype);
472 if (attr == NULL)
473 return 0;
474 garp_attr_event(app, attr, event);
475 return 0;
476}
477
478static int garp_pdu_parse_msg(struct garp_applicant *app, struct sk_buff *skb)
479{
480 const struct garp_msg_hdr *gm;
481
482 if (!pskb_may_pull(skb, sizeof(*gm)))
483 return -1;
484 gm = (struct garp_msg_hdr *)skb->data;
485 if (gm->attrtype == 0)
486 return -1;
487 skb_pull(skb, sizeof(*gm));
488
489 while (skb->len > 0) {
490 if (garp_pdu_parse_attr(app, skb, gm->attrtype) < 0)
491 return -1;
492 if (garp_pdu_parse_end_mark(skb) < 0)
493 break;
494 }
495 return 0;
496}
497
498static void garp_pdu_rcv(const struct stp_proto *proto, struct sk_buff *skb,
499 struct net_device *dev)
500{
501 struct garp_application *appl = proto->data;
502 struct garp_port *port;
503 struct garp_applicant *app;
504 const struct garp_pdu_hdr *gp;
505
506 port = rcu_dereference(dev->garp_port);
507 if (!port)
508 goto err;
509 app = rcu_dereference(port->applicants[appl->type]);
510 if (!app)
511 goto err;
512
513 if (!pskb_may_pull(skb, sizeof(*gp)))
514 goto err;
515 gp = (struct garp_pdu_hdr *)skb->data;
516 if (get_unaligned(&gp->protocol) != htons(GARP_PROTOCOL_ID))
517 goto err;
518 skb_pull(skb, sizeof(*gp));
519
520 spin_lock(&app->lock);
521 while (skb->len > 0) {
522 if (garp_pdu_parse_msg(app, skb) < 0)
523 break;
524 if (garp_pdu_parse_end_mark(skb) < 0)
525 break;
526 }
527 spin_unlock(&app->lock);
528err:
529 kfree_skb(skb);
530}
531
532static int garp_init_port(struct net_device *dev)
533{
534 struct garp_port *port;
535
536 port = kzalloc(sizeof(*port), GFP_KERNEL);
537 if (!port)
538 return -ENOMEM;
539 rcu_assign_pointer(dev->garp_port, port);
540 return 0;
541}
542
543static void garp_release_port(struct net_device *dev)
544{
545 struct garp_port *port = dev->garp_port;
546 unsigned int i;
547
548 for (i = 0; i <= GARP_APPLICATION_MAX; i++) {
549 if (port->applicants[i])
550 return;
551 }
552 rcu_assign_pointer(dev->garp_port, NULL);
553 synchronize_rcu();
554 kfree(port);
555}
556
557int garp_init_applicant(struct net_device *dev, struct garp_application *appl)
558{
559 struct garp_applicant *app;
560 int err;
561
562 ASSERT_RTNL();
563
564 if (!dev->garp_port) {
565 err = garp_init_port(dev);
566 if (err < 0)
567 goto err1;
568 }
569
570 err = -ENOMEM;
571 app = kzalloc(sizeof(*app), GFP_KERNEL);
572 if (!app)
573 goto err2;
574
575 err = dev_mc_add(dev, appl->proto.group_address, ETH_ALEN, 0);
576 if (err < 0)
577 goto err3;
578
579 app->dev = dev;
580 app->app = appl;
581 app->gid = RB_ROOT;
582 spin_lock_init(&app->lock);
583 skb_queue_head_init(&app->queue);
584 rcu_assign_pointer(dev->garp_port->applicants[appl->type], app);
585 setup_timer(&app->join_timer, garp_join_timer, (unsigned long)app);
586 garp_join_timer_arm(app);
587 return 0;
588
589err3:
590 kfree(app);
591err2:
592 garp_release_port(dev);
593err1:
594 return err;
595}
596EXPORT_SYMBOL_GPL(garp_init_applicant);
597
598void garp_uninit_applicant(struct net_device *dev, struct garp_application *appl)
599{
600 struct garp_port *port = dev->garp_port;
601 struct garp_applicant *app = port->applicants[appl->type];
602
603 ASSERT_RTNL();
604
605 rcu_assign_pointer(port->applicants[appl->type], NULL);
606 synchronize_rcu();
607
608 /* Delete timer and generate a final TRANSMIT_PDU event to flush out
609 * all pending messages before the applicant is gone. */
610 del_timer_sync(&app->join_timer);
611 garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU);
612 garp_pdu_queue(app);
613 garp_queue_xmit(app);
614
615 dev_mc_delete(dev, appl->proto.group_address, ETH_ALEN, 0);
616 kfree(app);
617 garp_release_port(dev);
618}
619EXPORT_SYMBOL_GPL(garp_uninit_applicant);
620
621int garp_register_application(struct garp_application *appl)
622{
623 appl->proto.rcv = garp_pdu_rcv;
624 appl->proto.data = appl;
625 return stp_proto_register(&appl->proto);
626}
627EXPORT_SYMBOL_GPL(garp_register_application);
628
629void garp_unregister_application(struct garp_application *appl)
630{
631 stp_proto_unregister(&appl->proto);
632}
633EXPORT_SYMBOL_GPL(garp_unregister_application);