Patrick McHardy | eca9eba | 2008-07-05 21:26:13 -0700 | [diff] [blame] | 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> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 17 | #include <linux/slab.h> |
Patrick McHardy | eca9eba | 2008-07-05 21:26:13 -0700 | [diff] [blame] | 18 | #include <net/llc.h> |
| 19 | #include <net/llc_pdu.h> |
| 20 | #include <net/garp.h> |
| 21 | #include <asm/unaligned.h> |
| 22 | |
| 23 | static unsigned int garp_join_time __read_mostly = 200; |
| 24 | module_param(garp_join_time, uint, 0644); |
| 25 | MODULE_PARM_DESC(garp_join_time, "Join time in ms (default 200ms)"); |
| 26 | MODULE_LICENSE("GPL"); |
| 27 | |
| 28 | static const struct garp_state_trans { |
| 29 | u8 state; |
| 30 | u8 action; |
| 31 | } garp_applicant_state_table[GARP_APPLICANT_MAX + 1][GARP_EVENT_MAX + 1] = { |
| 32 | [GARP_APPLICANT_VA] = { |
| 33 | [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_AA, |
| 34 | .action = GARP_ACTION_S_JOIN_IN }, |
| 35 | [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AA }, |
| 36 | [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA }, |
| 37 | [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA }, |
| 38 | [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VA }, |
| 39 | [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 40 | [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID }, |
| 41 | [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA }, |
| 42 | }, |
| 43 | [GARP_APPLICANT_AA] = { |
| 44 | [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_QA, |
| 45 | .action = GARP_ACTION_S_JOIN_IN }, |
| 46 | [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QA }, |
| 47 | [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA }, |
| 48 | [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA }, |
| 49 | [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VA }, |
| 50 | [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 51 | [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID }, |
| 52 | [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA }, |
| 53 | }, |
| 54 | [GARP_APPLICANT_QA] = { |
| 55 | [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID }, |
| 56 | [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QA }, |
| 57 | [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA }, |
| 58 | [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA }, |
| 59 | [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP }, |
| 60 | [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 61 | [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID }, |
| 62 | [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA }, |
| 63 | }, |
| 64 | [GARP_APPLICANT_LA] = { |
| 65 | [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_VO, |
| 66 | .action = GARP_ACTION_S_LEAVE_EMPTY }, |
| 67 | [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_LA }, |
| 68 | [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO }, |
| 69 | [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_LA }, |
| 70 | [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_LA }, |
| 71 | [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO }, |
| 72 | [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_VA }, |
| 73 | [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID }, |
| 74 | }, |
| 75 | [GARP_APPLICANT_VP] = { |
| 76 | [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_AA, |
| 77 | .action = GARP_ACTION_S_JOIN_IN }, |
| 78 | [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AP }, |
| 79 | [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 80 | [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 81 | [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP }, |
| 82 | [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 83 | [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID }, |
| 84 | [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_VO }, |
| 85 | }, |
| 86 | [GARP_APPLICANT_AP] = { |
| 87 | [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_QA, |
| 88 | .action = GARP_ACTION_S_JOIN_IN }, |
| 89 | [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QP }, |
| 90 | [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 91 | [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 92 | [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP }, |
| 93 | [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 94 | [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID }, |
| 95 | [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_AO }, |
| 96 | }, |
| 97 | [GARP_APPLICANT_QP] = { |
| 98 | [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID }, |
| 99 | [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QP }, |
| 100 | [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 101 | [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 102 | [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP }, |
| 103 | [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP }, |
| 104 | [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID }, |
| 105 | [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_QO }, |
| 106 | }, |
| 107 | [GARP_APPLICANT_VO] = { |
| 108 | [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID }, |
| 109 | [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AO }, |
| 110 | [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO }, |
| 111 | [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO }, |
| 112 | [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO }, |
| 113 | [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO }, |
| 114 | [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_VP }, |
| 115 | [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID }, |
| 116 | }, |
| 117 | [GARP_APPLICANT_AO] = { |
| 118 | [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID }, |
| 119 | [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO }, |
| 120 | [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO }, |
| 121 | [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO }, |
| 122 | [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO }, |
| 123 | [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO }, |
| 124 | [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_AP }, |
| 125 | [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID }, |
| 126 | }, |
| 127 | [GARP_APPLICANT_QO] = { |
| 128 | [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID }, |
| 129 | [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO }, |
| 130 | [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO }, |
| 131 | [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO }, |
| 132 | [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO }, |
| 133 | [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO }, |
| 134 | [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_QP }, |
| 135 | [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID }, |
| 136 | }, |
| 137 | }; |
| 138 | |
| 139 | static int garp_attr_cmp(const struct garp_attr *attr, |
| 140 | const void *data, u8 len, u8 type) |
| 141 | { |
| 142 | if (attr->type != type) |
| 143 | return attr->type - type; |
| 144 | if (attr->dlen != len) |
| 145 | return attr->dlen - len; |
| 146 | return memcmp(attr->data, data, len); |
| 147 | } |
| 148 | |
| 149 | static struct garp_attr *garp_attr_lookup(const struct garp_applicant *app, |
| 150 | const void *data, u8 len, u8 type) |
| 151 | { |
| 152 | struct rb_node *parent = app->gid.rb_node; |
| 153 | struct garp_attr *attr; |
| 154 | int d; |
| 155 | |
| 156 | while (parent) { |
| 157 | attr = rb_entry(parent, struct garp_attr, node); |
| 158 | d = garp_attr_cmp(attr, data, len, type); |
| 159 | if (d < 0) |
| 160 | parent = parent->rb_left; |
| 161 | else if (d > 0) |
| 162 | parent = parent->rb_right; |
| 163 | else |
| 164 | return attr; |
| 165 | } |
| 166 | return NULL; |
| 167 | } |
| 168 | |
| 169 | static void garp_attr_insert(struct garp_applicant *app, struct garp_attr *new) |
| 170 | { |
| 171 | struct rb_node *parent = NULL, **p = &app->gid.rb_node; |
| 172 | struct garp_attr *attr; |
| 173 | int d; |
| 174 | |
| 175 | while (*p) { |
| 176 | parent = *p; |
| 177 | attr = rb_entry(parent, struct garp_attr, node); |
| 178 | d = garp_attr_cmp(attr, new->data, new->dlen, new->type); |
| 179 | if (d < 0) |
| 180 | p = &parent->rb_left; |
| 181 | else if (d > 0) |
| 182 | p = &parent->rb_right; |
| 183 | } |
| 184 | rb_link_node(&new->node, parent, p); |
| 185 | rb_insert_color(&new->node, &app->gid); |
| 186 | } |
| 187 | |
| 188 | static struct garp_attr *garp_attr_create(struct garp_applicant *app, |
| 189 | const void *data, u8 len, u8 type) |
| 190 | { |
| 191 | struct garp_attr *attr; |
| 192 | |
| 193 | attr = kmalloc(sizeof(*attr) + len, GFP_ATOMIC); |
| 194 | if (!attr) |
| 195 | return attr; |
| 196 | attr->state = GARP_APPLICANT_VO; |
| 197 | attr->type = type; |
| 198 | attr->dlen = len; |
| 199 | memcpy(attr->data, data, len); |
| 200 | garp_attr_insert(app, attr); |
| 201 | return attr; |
| 202 | } |
| 203 | |
| 204 | static void garp_attr_destroy(struct garp_applicant *app, struct garp_attr *attr) |
| 205 | { |
| 206 | rb_erase(&attr->node, &app->gid); |
| 207 | kfree(attr); |
| 208 | } |
| 209 | |
| 210 | static int garp_pdu_init(struct garp_applicant *app) |
| 211 | { |
| 212 | struct sk_buff *skb; |
| 213 | struct garp_pdu_hdr *gp; |
| 214 | |
| 215 | #define LLC_RESERVE sizeof(struct llc_pdu_un) |
| 216 | skb = alloc_skb(app->dev->mtu + LL_RESERVED_SPACE(app->dev), |
| 217 | GFP_ATOMIC); |
| 218 | if (!skb) |
| 219 | return -ENOMEM; |
| 220 | |
| 221 | skb->dev = app->dev; |
| 222 | skb->protocol = htons(ETH_P_802_2); |
| 223 | skb_reserve(skb, LL_RESERVED_SPACE(app->dev) + LLC_RESERVE); |
| 224 | |
| 225 | gp = (struct garp_pdu_hdr *)__skb_put(skb, sizeof(*gp)); |
| 226 | put_unaligned(htons(GARP_PROTOCOL_ID), &gp->protocol); |
| 227 | |
| 228 | app->pdu = skb; |
| 229 | return 0; |
| 230 | } |
| 231 | |
| 232 | static int garp_pdu_append_end_mark(struct garp_applicant *app) |
| 233 | { |
| 234 | if (skb_tailroom(app->pdu) < sizeof(u8)) |
| 235 | return -1; |
| 236 | *(u8 *)__skb_put(app->pdu, sizeof(u8)) = GARP_END_MARK; |
| 237 | return 0; |
| 238 | } |
| 239 | |
| 240 | static void garp_pdu_queue(struct garp_applicant *app) |
| 241 | { |
| 242 | if (!app->pdu) |
| 243 | return; |
| 244 | |
| 245 | garp_pdu_append_end_mark(app); |
| 246 | garp_pdu_append_end_mark(app); |
| 247 | |
| 248 | llc_pdu_header_init(app->pdu, LLC_PDU_TYPE_U, LLC_SAP_BSPAN, |
| 249 | LLC_SAP_BSPAN, LLC_PDU_CMD); |
| 250 | llc_pdu_init_as_ui_cmd(app->pdu); |
| 251 | llc_mac_hdr_init(app->pdu, app->dev->dev_addr, |
| 252 | app->app->proto.group_address); |
| 253 | |
| 254 | skb_queue_tail(&app->queue, app->pdu); |
| 255 | app->pdu = NULL; |
| 256 | } |
| 257 | |
| 258 | static void garp_queue_xmit(struct garp_applicant *app) |
| 259 | { |
| 260 | struct sk_buff *skb; |
| 261 | |
| 262 | while ((skb = skb_dequeue(&app->queue))) |
| 263 | dev_queue_xmit(skb); |
| 264 | } |
| 265 | |
| 266 | static int garp_pdu_append_msg(struct garp_applicant *app, u8 attrtype) |
| 267 | { |
| 268 | struct garp_msg_hdr *gm; |
| 269 | |
| 270 | if (skb_tailroom(app->pdu) < sizeof(*gm)) |
| 271 | return -1; |
| 272 | gm = (struct garp_msg_hdr *)__skb_put(app->pdu, sizeof(*gm)); |
| 273 | gm->attrtype = attrtype; |
| 274 | garp_cb(app->pdu)->cur_type = attrtype; |
| 275 | return 0; |
| 276 | } |
| 277 | |
| 278 | static int garp_pdu_append_attr(struct garp_applicant *app, |
| 279 | const struct garp_attr *attr, |
| 280 | enum garp_attr_event event) |
| 281 | { |
| 282 | struct garp_attr_hdr *ga; |
| 283 | unsigned int len; |
| 284 | int err; |
| 285 | again: |
| 286 | if (!app->pdu) { |
| 287 | err = garp_pdu_init(app); |
| 288 | if (err < 0) |
| 289 | return err; |
| 290 | } |
| 291 | |
| 292 | if (garp_cb(app->pdu)->cur_type != attr->type) { |
| 293 | if (garp_cb(app->pdu)->cur_type && |
| 294 | garp_pdu_append_end_mark(app) < 0) |
| 295 | goto queue; |
| 296 | if (garp_pdu_append_msg(app, attr->type) < 0) |
| 297 | goto queue; |
| 298 | } |
| 299 | |
| 300 | len = sizeof(*ga) + attr->dlen; |
| 301 | if (skb_tailroom(app->pdu) < len) |
| 302 | goto queue; |
| 303 | ga = (struct garp_attr_hdr *)__skb_put(app->pdu, len); |
| 304 | ga->len = len; |
| 305 | ga->event = event; |
| 306 | memcpy(ga->data, attr->data, attr->dlen); |
| 307 | return 0; |
| 308 | |
| 309 | queue: |
| 310 | garp_pdu_queue(app); |
| 311 | goto again; |
| 312 | } |
| 313 | |
| 314 | static void garp_attr_event(struct garp_applicant *app, |
| 315 | struct garp_attr *attr, enum garp_event event) |
| 316 | { |
| 317 | enum garp_applicant_state state; |
| 318 | |
| 319 | state = garp_applicant_state_table[attr->state][event].state; |
| 320 | if (state == GARP_APPLICANT_INVALID) |
| 321 | return; |
| 322 | |
| 323 | switch (garp_applicant_state_table[attr->state][event].action) { |
| 324 | case GARP_ACTION_NONE: |
| 325 | break; |
| 326 | case GARP_ACTION_S_JOIN_IN: |
Patrick McHardy | 51ce7ec | 2008-07-16 20:51:47 -0700 | [diff] [blame] | 327 | /* When appending the attribute fails, don't update state in |
| 328 | * order to retry on next TRANSMIT_PDU event. */ |
| 329 | if (garp_pdu_append_attr(app, attr, GARP_JOIN_IN) < 0) |
| 330 | return; |
Patrick McHardy | eca9eba | 2008-07-05 21:26:13 -0700 | [diff] [blame] | 331 | break; |
| 332 | case GARP_ACTION_S_LEAVE_EMPTY: |
| 333 | garp_pdu_append_attr(app, attr, GARP_LEAVE_EMPTY); |
| 334 | /* As a pure applicant, sending a leave message implies that |
| 335 | * the attribute was unregistered and can be destroyed. */ |
| 336 | garp_attr_destroy(app, attr); |
| 337 | return; |
| 338 | default: |
| 339 | WARN_ON(1); |
| 340 | } |
| 341 | |
| 342 | attr->state = state; |
| 343 | } |
| 344 | |
| 345 | int garp_request_join(const struct net_device *dev, |
| 346 | const struct garp_application *appl, |
| 347 | const void *data, u8 len, u8 type) |
| 348 | { |
| 349 | struct garp_port *port = dev->garp_port; |
| 350 | struct garp_applicant *app = port->applicants[appl->type]; |
| 351 | struct garp_attr *attr; |
| 352 | |
| 353 | spin_lock_bh(&app->lock); |
| 354 | attr = garp_attr_create(app, data, len, type); |
| 355 | if (!attr) { |
| 356 | spin_unlock_bh(&app->lock); |
| 357 | return -ENOMEM; |
| 358 | } |
| 359 | garp_attr_event(app, attr, GARP_EVENT_REQ_JOIN); |
| 360 | spin_unlock_bh(&app->lock); |
| 361 | return 0; |
| 362 | } |
| 363 | EXPORT_SYMBOL_GPL(garp_request_join); |
| 364 | |
| 365 | void garp_request_leave(const struct net_device *dev, |
| 366 | const struct garp_application *appl, |
| 367 | const void *data, u8 len, u8 type) |
| 368 | { |
| 369 | struct garp_port *port = dev->garp_port; |
| 370 | struct garp_applicant *app = port->applicants[appl->type]; |
| 371 | struct garp_attr *attr; |
| 372 | |
| 373 | spin_lock_bh(&app->lock); |
| 374 | attr = garp_attr_lookup(app, data, len, type); |
| 375 | if (!attr) { |
| 376 | spin_unlock_bh(&app->lock); |
| 377 | return; |
| 378 | } |
| 379 | garp_attr_event(app, attr, GARP_EVENT_REQ_LEAVE); |
| 380 | spin_unlock_bh(&app->lock); |
| 381 | } |
| 382 | EXPORT_SYMBOL_GPL(garp_request_leave); |
| 383 | |
| 384 | static void garp_gid_event(struct garp_applicant *app, enum garp_event event) |
| 385 | { |
| 386 | struct rb_node *node, *next; |
| 387 | struct garp_attr *attr; |
| 388 | |
| 389 | for (node = rb_first(&app->gid); |
| 390 | next = node ? rb_next(node) : NULL, node != NULL; |
| 391 | node = next) { |
| 392 | attr = rb_entry(node, struct garp_attr, node); |
| 393 | garp_attr_event(app, attr, event); |
| 394 | } |
| 395 | } |
| 396 | |
| 397 | static void garp_join_timer_arm(struct garp_applicant *app) |
| 398 | { |
| 399 | unsigned long delay; |
| 400 | |
| 401 | delay = (u64)msecs_to_jiffies(garp_join_time) * net_random() >> 32; |
| 402 | mod_timer(&app->join_timer, jiffies + delay); |
| 403 | } |
| 404 | |
| 405 | static void garp_join_timer(unsigned long data) |
| 406 | { |
| 407 | struct garp_applicant *app = (struct garp_applicant *)data; |
| 408 | |
| 409 | spin_lock(&app->lock); |
| 410 | garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU); |
| 411 | garp_pdu_queue(app); |
| 412 | spin_unlock(&app->lock); |
| 413 | |
| 414 | garp_queue_xmit(app); |
| 415 | garp_join_timer_arm(app); |
| 416 | } |
| 417 | |
| 418 | static int garp_pdu_parse_end_mark(struct sk_buff *skb) |
| 419 | { |
| 420 | if (!pskb_may_pull(skb, sizeof(u8))) |
| 421 | return -1; |
| 422 | if (*skb->data == GARP_END_MARK) { |
| 423 | skb_pull(skb, sizeof(u8)); |
| 424 | return -1; |
| 425 | } |
| 426 | return 0; |
| 427 | } |
| 428 | |
| 429 | static int garp_pdu_parse_attr(struct garp_applicant *app, struct sk_buff *skb, |
| 430 | u8 attrtype) |
| 431 | { |
| 432 | const struct garp_attr_hdr *ga; |
| 433 | struct garp_attr *attr; |
| 434 | enum garp_event event; |
| 435 | unsigned int dlen; |
| 436 | |
| 437 | if (!pskb_may_pull(skb, sizeof(*ga))) |
| 438 | return -1; |
| 439 | ga = (struct garp_attr_hdr *)skb->data; |
| 440 | if (ga->len < sizeof(*ga)) |
| 441 | return -1; |
| 442 | |
| 443 | if (!pskb_may_pull(skb, ga->len)) |
| 444 | return -1; |
| 445 | skb_pull(skb, ga->len); |
| 446 | dlen = sizeof(*ga) - ga->len; |
| 447 | |
| 448 | if (attrtype > app->app->maxattr) |
| 449 | return 0; |
| 450 | |
| 451 | switch (ga->event) { |
| 452 | case GARP_LEAVE_ALL: |
| 453 | if (dlen != 0) |
| 454 | return -1; |
| 455 | garp_gid_event(app, GARP_EVENT_R_LEAVE_EMPTY); |
| 456 | return 0; |
| 457 | case GARP_JOIN_EMPTY: |
| 458 | event = GARP_EVENT_R_JOIN_EMPTY; |
| 459 | break; |
| 460 | case GARP_JOIN_IN: |
| 461 | event = GARP_EVENT_R_JOIN_IN; |
| 462 | break; |
| 463 | case GARP_LEAVE_EMPTY: |
| 464 | event = GARP_EVENT_R_LEAVE_EMPTY; |
| 465 | break; |
| 466 | case GARP_EMPTY: |
| 467 | event = GARP_EVENT_R_EMPTY; |
| 468 | break; |
| 469 | default: |
| 470 | return 0; |
| 471 | } |
| 472 | |
| 473 | if (dlen == 0) |
| 474 | return -1; |
| 475 | attr = garp_attr_lookup(app, ga->data, dlen, attrtype); |
| 476 | if (attr == NULL) |
| 477 | return 0; |
| 478 | garp_attr_event(app, attr, event); |
| 479 | return 0; |
| 480 | } |
| 481 | |
| 482 | static int garp_pdu_parse_msg(struct garp_applicant *app, struct sk_buff *skb) |
| 483 | { |
| 484 | const struct garp_msg_hdr *gm; |
| 485 | |
| 486 | if (!pskb_may_pull(skb, sizeof(*gm))) |
| 487 | return -1; |
| 488 | gm = (struct garp_msg_hdr *)skb->data; |
| 489 | if (gm->attrtype == 0) |
| 490 | return -1; |
| 491 | skb_pull(skb, sizeof(*gm)); |
| 492 | |
| 493 | while (skb->len > 0) { |
| 494 | if (garp_pdu_parse_attr(app, skb, gm->attrtype) < 0) |
| 495 | return -1; |
| 496 | if (garp_pdu_parse_end_mark(skb) < 0) |
| 497 | break; |
| 498 | } |
| 499 | return 0; |
| 500 | } |
| 501 | |
| 502 | static void garp_pdu_rcv(const struct stp_proto *proto, struct sk_buff *skb, |
| 503 | struct net_device *dev) |
| 504 | { |
| 505 | struct garp_application *appl = proto->data; |
| 506 | struct garp_port *port; |
| 507 | struct garp_applicant *app; |
| 508 | const struct garp_pdu_hdr *gp; |
| 509 | |
| 510 | port = rcu_dereference(dev->garp_port); |
| 511 | if (!port) |
| 512 | goto err; |
| 513 | app = rcu_dereference(port->applicants[appl->type]); |
| 514 | if (!app) |
| 515 | goto err; |
| 516 | |
| 517 | if (!pskb_may_pull(skb, sizeof(*gp))) |
| 518 | goto err; |
| 519 | gp = (struct garp_pdu_hdr *)skb->data; |
| 520 | if (get_unaligned(&gp->protocol) != htons(GARP_PROTOCOL_ID)) |
| 521 | goto err; |
| 522 | skb_pull(skb, sizeof(*gp)); |
| 523 | |
| 524 | spin_lock(&app->lock); |
| 525 | while (skb->len > 0) { |
| 526 | if (garp_pdu_parse_msg(app, skb) < 0) |
| 527 | break; |
| 528 | if (garp_pdu_parse_end_mark(skb) < 0) |
| 529 | break; |
| 530 | } |
| 531 | spin_unlock(&app->lock); |
| 532 | err: |
| 533 | kfree_skb(skb); |
| 534 | } |
| 535 | |
| 536 | static int garp_init_port(struct net_device *dev) |
| 537 | { |
| 538 | struct garp_port *port; |
| 539 | |
| 540 | port = kzalloc(sizeof(*port), GFP_KERNEL); |
| 541 | if (!port) |
| 542 | return -ENOMEM; |
| 543 | rcu_assign_pointer(dev->garp_port, port); |
| 544 | return 0; |
| 545 | } |
| 546 | |
| 547 | static void garp_release_port(struct net_device *dev) |
| 548 | { |
| 549 | struct garp_port *port = dev->garp_port; |
| 550 | unsigned int i; |
| 551 | |
| 552 | for (i = 0; i <= GARP_APPLICATION_MAX; i++) { |
| 553 | if (port->applicants[i]) |
| 554 | return; |
| 555 | } |
| 556 | rcu_assign_pointer(dev->garp_port, NULL); |
| 557 | synchronize_rcu(); |
| 558 | kfree(port); |
| 559 | } |
| 560 | |
| 561 | int garp_init_applicant(struct net_device *dev, struct garp_application *appl) |
| 562 | { |
| 563 | struct garp_applicant *app; |
| 564 | int err; |
| 565 | |
| 566 | ASSERT_RTNL(); |
| 567 | |
| 568 | if (!dev->garp_port) { |
| 569 | err = garp_init_port(dev); |
| 570 | if (err < 0) |
| 571 | goto err1; |
| 572 | } |
| 573 | |
| 574 | err = -ENOMEM; |
| 575 | app = kzalloc(sizeof(*app), GFP_KERNEL); |
| 576 | if (!app) |
| 577 | goto err2; |
| 578 | |
Jiri Pirko | 22bedad3 | 2010-04-01 21:22:57 +0000 | [diff] [blame] | 579 | err = dev_mc_add(dev, appl->proto.group_address); |
Patrick McHardy | eca9eba | 2008-07-05 21:26:13 -0700 | [diff] [blame] | 580 | if (err < 0) |
| 581 | goto err3; |
| 582 | |
| 583 | app->dev = dev; |
| 584 | app->app = appl; |
| 585 | app->gid = RB_ROOT; |
| 586 | spin_lock_init(&app->lock); |
| 587 | skb_queue_head_init(&app->queue); |
| 588 | rcu_assign_pointer(dev->garp_port->applicants[appl->type], app); |
| 589 | setup_timer(&app->join_timer, garp_join_timer, (unsigned long)app); |
| 590 | garp_join_timer_arm(app); |
| 591 | return 0; |
| 592 | |
| 593 | err3: |
| 594 | kfree(app); |
| 595 | err2: |
| 596 | garp_release_port(dev); |
| 597 | err1: |
| 598 | return err; |
| 599 | } |
| 600 | EXPORT_SYMBOL_GPL(garp_init_applicant); |
| 601 | |
| 602 | void garp_uninit_applicant(struct net_device *dev, struct garp_application *appl) |
| 603 | { |
| 604 | struct garp_port *port = dev->garp_port; |
| 605 | struct garp_applicant *app = port->applicants[appl->type]; |
| 606 | |
| 607 | ASSERT_RTNL(); |
| 608 | |
| 609 | rcu_assign_pointer(port->applicants[appl->type], NULL); |
| 610 | synchronize_rcu(); |
| 611 | |
| 612 | /* Delete timer and generate a final TRANSMIT_PDU event to flush out |
| 613 | * all pending messages before the applicant is gone. */ |
| 614 | del_timer_sync(&app->join_timer); |
| 615 | garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU); |
| 616 | garp_pdu_queue(app); |
| 617 | garp_queue_xmit(app); |
| 618 | |
Jiri Pirko | 22bedad3 | 2010-04-01 21:22:57 +0000 | [diff] [blame] | 619 | dev_mc_del(dev, appl->proto.group_address); |
Patrick McHardy | eca9eba | 2008-07-05 21:26:13 -0700 | [diff] [blame] | 620 | kfree(app); |
| 621 | garp_release_port(dev); |
| 622 | } |
| 623 | EXPORT_SYMBOL_GPL(garp_uninit_applicant); |
| 624 | |
| 625 | int garp_register_application(struct garp_application *appl) |
| 626 | { |
| 627 | appl->proto.rcv = garp_pdu_rcv; |
| 628 | appl->proto.data = appl; |
| 629 | return stp_proto_register(&appl->proto); |
| 630 | } |
| 631 | EXPORT_SYMBOL_GPL(garp_register_application); |
| 632 | |
| 633 | void garp_unregister_application(struct garp_application *appl) |
| 634 | { |
| 635 | stp_proto_unregister(&appl->proto); |
| 636 | } |
| 637 | EXPORT_SYMBOL_GPL(garp_unregister_application); |