garp.c revision eca9ebac651f774d8b10fce7c5d173c3c3d3394f
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); 634