Johannes Berg | 4855d25 | 2006-01-12 21:12:59 +0100 | [diff] [blame] | 1 | /* |
| 2 | * This file contains the softmac's association logic. |
| 3 | * |
Johannes Berg | 7985905 | 2006-01-31 19:31:41 +0100 | [diff] [blame] | 4 | * Copyright (c) 2005, 2006 Johannes Berg <johannes@sipsolutions.net> |
| 5 | * Joseph Jezak <josejx@gentoo.org> |
| 6 | * Larry Finger <Larry.Finger@lwfinger.net> |
| 7 | * Danny van Dyk <kugelfang@gentoo.org> |
| 8 | * Michael Buesch <mbuesch@freenet.de> |
Johannes Berg | 4855d25 | 2006-01-12 21:12:59 +0100 | [diff] [blame] | 9 | * |
| 10 | * This program is free software; you can redistribute it and/or modify it |
| 11 | * under the terms of version 2 of the GNU General Public License as |
| 12 | * published by the Free Software Foundation. |
| 13 | * |
| 14 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 15 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 16 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 17 | * more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU General Public License |
| 20 | * along with this program; if not, write to the Free Software |
| 21 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 22 | * |
| 23 | * The full GNU General Public License is included in this distribution in the |
| 24 | * file called COPYING. |
| 25 | */ |
| 26 | |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 27 | #include "ieee80211softmac_priv.h" |
| 28 | |
| 29 | /* |
| 30 | * Overview |
| 31 | * |
| 32 | * Before you can associate, you have to authenticate. |
| 33 | * |
| 34 | */ |
| 35 | |
| 36 | /* Sends out an association request to the desired AP */ |
| 37 | static void |
| 38 | ieee80211softmac_assoc(struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net) |
| 39 | { |
| 40 | unsigned long flags; |
John W. Linville | 9a107aa | 2006-03-22 17:29:32 -0500 | [diff] [blame] | 41 | |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 42 | /* Switch to correct channel for this network */ |
| 43 | mac->set_channel(mac->dev, net->channel); |
| 44 | |
| 45 | /* Send association request */ |
| 46 | ieee80211softmac_send_mgt_frame(mac, net, IEEE80211_STYPE_ASSOC_REQ, 0); |
| 47 | |
| 48 | dprintk(KERN_INFO PFX "sent association request!\n"); |
| 49 | |
| 50 | /* Change the state to associating */ |
| 51 | spin_lock_irqsave(&mac->lock, flags); |
| 52 | mac->associnfo.associating = 1; |
| 53 | mac->associated = 0; /* just to make sure */ |
| 54 | spin_unlock_irqrestore(&mac->lock, flags); |
| 55 | |
| 56 | /* Set a timer for timeout */ |
| 57 | /* FIXME: make timeout configurable */ |
Johannes Berg | 5c4df6d | 2006-01-06 01:43:45 +0100 | [diff] [blame] | 58 | schedule_delayed_work(&mac->associnfo.timeout, 5 * HZ); |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 59 | } |
| 60 | |
| 61 | void |
| 62 | ieee80211softmac_assoc_timeout(void *d) |
| 63 | { |
| 64 | struct ieee80211softmac_device *mac = (struct ieee80211softmac_device *)d; |
| 65 | unsigned long flags; |
| 66 | |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 67 | spin_lock_irqsave(&mac->lock, flags); |
| 68 | /* we might race against ieee80211softmac_handle_assoc_response, |
| 69 | * so make sure only one of us does something */ |
| 70 | if (!mac->associnfo.associating) { |
| 71 | spin_unlock_irqrestore(&mac->lock, flags); |
| 72 | return; |
| 73 | } |
| 74 | mac->associnfo.associating = 0; |
| 75 | mac->associnfo.bssvalid = 0; |
| 76 | mac->associated = 0; |
| 77 | spin_unlock_irqrestore(&mac->lock, flags); |
| 78 | |
| 79 | dprintk(KERN_INFO PFX "assoc request timed out!\n"); |
| 80 | /* FIXME: we need to know the network here. that requires a bit of restructuring */ |
| 81 | ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_TIMEOUT, NULL); |
| 82 | } |
| 83 | |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 84 | /* Sends out a disassociation request to the desired AP */ |
| 85 | static void |
| 86 | ieee80211softmac_disassoc(struct ieee80211softmac_device *mac, u16 reason) |
| 87 | { |
| 88 | unsigned long flags; |
| 89 | struct ieee80211softmac_network *found; |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 90 | |
| 91 | if (mac->associnfo.bssvalid && mac->associated) { |
| 92 | found = ieee80211softmac_get_network_by_bssid(mac, mac->associnfo.bssid); |
| 93 | if (found) |
| 94 | ieee80211softmac_send_mgt_frame(mac, found, IEEE80211_STYPE_DISASSOC, reason); |
| 95 | } else if (mac->associnfo.associating) { |
| 96 | cancel_delayed_work(&mac->associnfo.timeout); |
| 97 | } |
| 98 | |
| 99 | /* Change our state */ |
| 100 | spin_lock_irqsave(&mac->lock, flags); |
| 101 | /* Do NOT clear bssvalid as that will break ieee80211softmac_assoc_work! */ |
| 102 | mac->associated = 0; |
| 103 | mac->associnfo.associating = 0; |
| 104 | spin_unlock_irqrestore(&mac->lock, flags); |
| 105 | } |
| 106 | |
| 107 | static inline int |
| 108 | we_support_all_basic_rates(struct ieee80211softmac_device *mac, u8 *from, u8 from_len) |
| 109 | { |
| 110 | int idx, search, found; |
| 111 | u8 rate, search_rate; |
| 112 | |
| 113 | for (idx = 0; idx < (from_len); idx++) { |
| 114 | rate = (from)[idx]; |
| 115 | if (!(rate & IEEE80211_BASIC_RATE_MASK)) |
| 116 | continue; |
| 117 | found = 0; |
| 118 | rate &= ~IEEE80211_BASIC_RATE_MASK; |
| 119 | for (search = 0; search < mac->ratesinfo.count; search++) { |
| 120 | search_rate = mac->ratesinfo.rates[search]; |
| 121 | search_rate &= ~IEEE80211_BASIC_RATE_MASK; |
| 122 | if (rate == search_rate) { |
| 123 | found = 1; |
| 124 | break; |
| 125 | } |
| 126 | } |
| 127 | if (!found) |
| 128 | return 0; |
| 129 | } |
| 130 | return 1; |
| 131 | } |
| 132 | |
| 133 | static int |
| 134 | network_matches_request(struct ieee80211softmac_device *mac, struct ieee80211_network *net) |
| 135 | { |
| 136 | /* we cannot associate to networks whose name we don't know */ |
| 137 | if (ieee80211_is_empty_essid(net->ssid, net->ssid_len)) |
| 138 | return 0; |
| 139 | /* do not associate to a network whose BSSBasicRateSet we cannot support */ |
| 140 | if (!we_support_all_basic_rates(mac, net->rates, net->rates_len)) |
| 141 | return 0; |
| 142 | /* do we really need to check the ex rates? */ |
| 143 | if (!we_support_all_basic_rates(mac, net->rates_ex, net->rates_ex_len)) |
| 144 | return 0; |
| 145 | |
| 146 | /* if 'ANY' network requested, take any that doesn't have privacy enabled */ |
| 147 | if (mac->associnfo.req_essid.len == 0 |
| 148 | && !(net->capability & WLAN_CAPABILITY_PRIVACY)) |
| 149 | return 1; |
| 150 | if (net->ssid_len != mac->associnfo.req_essid.len) |
| 151 | return 0; |
| 152 | if (!memcmp(net->ssid, mac->associnfo.req_essid.data, mac->associnfo.req_essid.len)) |
| 153 | return 1; |
| 154 | return 0; |
| 155 | } |
| 156 | |
| 157 | static void |
| 158 | ieee80211softmac_assoc_notify(struct net_device *dev, void *context) |
| 159 | { |
| 160 | struct ieee80211softmac_device *mac = ieee80211_priv(dev); |
| 161 | ieee80211softmac_assoc_work((void*)mac); |
| 162 | } |
| 163 | |
| 164 | /* This function is called to handle userspace requests (asynchronously) */ |
| 165 | void |
| 166 | ieee80211softmac_assoc_work(void *d) |
| 167 | { |
| 168 | struct ieee80211softmac_device *mac = (struct ieee80211softmac_device *)d; |
| 169 | struct ieee80211softmac_network *found = NULL; |
| 170 | struct ieee80211_network *net = NULL, *best = NULL; |
| 171 | unsigned long flags; |
| 172 | |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 173 | /* meh */ |
| 174 | if (mac->associated) |
| 175 | ieee80211softmac_disassoc(mac, WLAN_REASON_DISASSOC_STA_HAS_LEFT); |
| 176 | |
| 177 | /* try to find the requested network in our list, if we found one already */ |
| 178 | if (mac->associnfo.bssvalid) |
| 179 | found = ieee80211softmac_get_network_by_bssid(mac, mac->associnfo.bssid); |
| 180 | |
Johannes Berg | 1dc0977 | 2006-01-11 10:46:16 +0100 | [diff] [blame] | 181 | /* Search the ieee80211 networks for this network if we didn't find it by bssid, |
| 182 | * but only if we've scanned at least once (to get a better list of networks to |
| 183 | * select from). If we have not scanned before, the !found logic below will be |
| 184 | * invoked and will scan. */ |
| 185 | if (!found && (mac->associnfo.scan_retry < IEEE80211SOFTMAC_ASSOC_SCAN_RETRY_LIMIT)) |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 186 | { |
Johannes Berg | 78e4f36 | 2006-01-10 18:56:32 +0100 | [diff] [blame] | 187 | s8 rssi = -128; /* if I don't initialise, gcc emits an invalid warning |
| 188 | because it cannot follow the best pointer logic. */ |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 189 | spin_lock_irqsave(&mac->ieee->lock, flags); |
| 190 | list_for_each_entry(net, &mac->ieee->network_list, list) { |
| 191 | /* we're supposed to find the network with |
| 192 | * the best signal here, as we're asked to join |
| 193 | * any network with a specific ESSID, and many |
| 194 | * different ones could have that. |
| 195 | * |
Johannes Berg | 78e4f36 | 2006-01-10 18:56:32 +0100 | [diff] [blame] | 196 | * I'll for now just go with the reported rssi. |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 197 | * |
| 198 | * We also should take into account the rateset |
| 199 | * here to find the best BSSID to try. |
| 200 | */ |
| 201 | if (network_matches_request(mac, net)) { |
| 202 | if (!best) { |
| 203 | best = net; |
Johannes Berg | 78e4f36 | 2006-01-10 18:56:32 +0100 | [diff] [blame] | 204 | rssi = best->stats.rssi; |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 205 | continue; |
| 206 | } |
| 207 | /* we already had a matching network, so |
| 208 | * compare their properties to get the |
| 209 | * better of the two ... (see above) |
| 210 | */ |
Johannes Berg | 78e4f36 | 2006-01-10 18:56:32 +0100 | [diff] [blame] | 211 | if (rssi < net->stats.rssi) { |
| 212 | best = net; |
| 213 | rssi = best->stats.rssi; |
| 214 | } |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 215 | } |
| 216 | } |
| 217 | /* if we unlock here, we might get interrupted and the `best' |
| 218 | * pointer could go stale */ |
| 219 | if (best) { |
| 220 | found = ieee80211softmac_create_network(mac, best); |
| 221 | /* if found is still NULL, then we got -ENOMEM somewhere */ |
| 222 | if (found) |
| 223 | ieee80211softmac_add_network(mac, found); |
| 224 | } |
| 225 | spin_unlock_irqrestore(&mac->ieee->lock, flags); |
| 226 | } |
| 227 | |
| 228 | if (!found) { |
| 229 | if (mac->associnfo.scan_retry > 0) { |
| 230 | spin_lock_irqsave(&mac->lock, flags); |
| 231 | mac->associnfo.scan_retry--; |
| 232 | spin_unlock_irqrestore(&mac->lock, flags); |
| 233 | |
| 234 | /* We know of no such network. Let's scan. |
| 235 | * NB: this also happens if we had no memory to copy the network info... |
| 236 | * Maybe we can hope to have more memory after scanning finishes ;) |
| 237 | */ |
Johannes Berg | 1dc0977 | 2006-01-11 10:46:16 +0100 | [diff] [blame] | 238 | dprintk(KERN_INFO PFX "Associate: Scanning for networks first.\n"); |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 239 | ieee80211softmac_notify(mac->dev, IEEE80211SOFTMAC_EVENT_SCAN_FINISHED, ieee80211softmac_assoc_notify, NULL); |
| 240 | if (ieee80211softmac_start_scan(mac)) |
Johannes Berg | 1dc0977 | 2006-01-11 10:46:16 +0100 | [diff] [blame] | 241 | dprintk(KERN_INFO PFX "Associate: failed to initiate scan. Is device up?\n"); |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 242 | return; |
| 243 | } |
| 244 | else { |
| 245 | spin_lock_irqsave(&mac->lock, flags); |
| 246 | mac->associnfo.associating = 0; |
| 247 | mac->associated = 0; |
| 248 | spin_unlock_irqrestore(&mac->lock, flags); |
| 249 | |
Johannes Berg | 1dc0977 | 2006-01-11 10:46:16 +0100 | [diff] [blame] | 250 | dprintk(KERN_INFO PFX "Unable to find matching network after scan!\n"); |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 251 | ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_NET_NOT_FOUND, NULL); |
| 252 | return; |
| 253 | } |
| 254 | } |
| 255 | |
| 256 | mac->associnfo.bssvalid = 1; |
| 257 | memcpy(mac->associnfo.bssid, found->bssid, ETH_ALEN); |
| 258 | /* copy the ESSID for displaying it */ |
| 259 | mac->associnfo.associate_essid.len = found->essid.len; |
| 260 | memcpy(mac->associnfo.associate_essid.data, found->essid.data, IW_ESSID_MAX_SIZE + 1); |
| 261 | |
| 262 | /* we found a network! authenticate (if necessary) and associate to it. */ |
| 263 | if (!found->authenticated) { |
| 264 | /* This relies on the fact that _auth_req only queues the work, |
| 265 | * otherwise adding the notification would be racy. */ |
| 266 | if (!ieee80211softmac_auth_req(mac, found)) { |
| 267 | dprintk(KERN_INFO PFX "cannot associate without being authenticated, requested authentication\n"); |
| 268 | ieee80211softmac_notify_internal(mac, IEEE80211SOFTMAC_EVENT_ANY, found, ieee80211softmac_assoc_notify, NULL, GFP_KERNEL); |
| 269 | } else { |
| 270 | printkl(KERN_WARNING PFX "Not authenticated, but requesting authentication failed. Giving up to associate\n"); |
| 271 | ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, found); |
| 272 | } |
| 273 | return; |
| 274 | } |
| 275 | /* finally! now we can start associating */ |
| 276 | ieee80211softmac_assoc(mac, found); |
| 277 | } |
| 278 | |
| 279 | /* call this to do whatever is necessary when we're associated */ |
| 280 | static void |
| 281 | ieee80211softmac_associated(struct ieee80211softmac_device *mac, |
| 282 | struct ieee80211_assoc_response * resp, |
| 283 | struct ieee80211softmac_network *net) |
| 284 | { |
| 285 | mac->associnfo.associating = 0; |
| 286 | mac->associated = 1; |
| 287 | if (mac->set_bssid_filter) |
| 288 | mac->set_bssid_filter(mac->dev, net->bssid); |
| 289 | memcpy(mac->ieee->bssid, net->bssid, ETH_ALEN); |
Johannes Berg | 2dd5080 | 2006-01-06 18:11:23 +0100 | [diff] [blame] | 290 | netif_carrier_on(mac->dev); |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 291 | |
| 292 | mac->association_id = le16_to_cpup(&resp->aid); |
| 293 | } |
| 294 | |
| 295 | /* received frame handling functions */ |
| 296 | int |
| 297 | ieee80211softmac_handle_assoc_response(struct net_device * dev, |
| 298 | struct ieee80211_assoc_response * resp, |
| 299 | struct ieee80211_network * _ieee80211_network_do_not_use) |
| 300 | { |
| 301 | /* NOTE: the network parameter has to be ignored by |
| 302 | * this code because it is the ieee80211's pointer |
| 303 | * to the struct, not ours (we made a copy) |
| 304 | */ |
| 305 | struct ieee80211softmac_device *mac = ieee80211_priv(dev); |
| 306 | u16 status = le16_to_cpup(&resp->status); |
| 307 | struct ieee80211softmac_network *network = NULL; |
| 308 | unsigned long flags; |
| 309 | |
| 310 | spin_lock_irqsave(&mac->lock, flags); |
| 311 | |
| 312 | if (!mac->associnfo.associating) { |
| 313 | /* we race against the timeout function, so make sure |
| 314 | * only one of us can do work */ |
| 315 | spin_unlock_irqrestore(&mac->lock, flags); |
| 316 | return 0; |
| 317 | } |
| 318 | network = ieee80211softmac_get_network_by_bssid_locked(mac, resp->header.addr3); |
| 319 | |
| 320 | /* someone sending us things without us knowing him? Ignore. */ |
| 321 | if (!network) { |
| 322 | dprintk(KERN_INFO PFX "Received unrequested assocation response from " MAC_FMT "\n", MAC_ARG(resp->header.addr3)); |
| 323 | spin_unlock_irqrestore(&mac->lock, flags); |
| 324 | return 0; |
| 325 | } |
| 326 | |
| 327 | /* now that we know it was for us, we can cancel the timeout */ |
| 328 | cancel_delayed_work(&mac->associnfo.timeout); |
| 329 | |
| 330 | switch (status) { |
| 331 | case 0: |
| 332 | dprintk(KERN_INFO PFX "associated!\n"); |
| 333 | ieee80211softmac_associated(mac, resp, network); |
| 334 | ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATED, network); |
| 335 | break; |
| 336 | case WLAN_REASON_STA_REQ_ASSOC_WITHOUT_AUTH: |
| 337 | if (!network->auth_desynced_once) { |
| 338 | /* there seem to be a few rare cases where our view of |
| 339 | * the world is obscured, or buggy APs that don't DEAUTH |
| 340 | * us properly. So we handle that, but allow it only once. |
| 341 | */ |
| 342 | printkl(KERN_INFO PFX "We were not authenticated during association, retrying...\n"); |
| 343 | network->authenticated = 0; |
| 344 | /* we don't want to do this more than once ... */ |
| 345 | network->auth_desynced_once = 1; |
Johannes Berg | 5c4df6d | 2006-01-06 01:43:45 +0100 | [diff] [blame] | 346 | schedule_work(&mac->associnfo.work); |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 347 | break; |
| 348 | } |
| 349 | default: |
| 350 | dprintk(KERN_INFO PFX "associating failed (reason: 0x%x)!\n", status); |
| 351 | mac->associnfo.associating = 0; |
| 352 | mac->associnfo.bssvalid = 0; |
| 353 | mac->associated = 0; |
| 354 | ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, network); |
| 355 | } |
| 356 | |
| 357 | spin_unlock_irqrestore(&mac->lock, flags); |
| 358 | return 0; |
| 359 | } |
| 360 | |
| 361 | int |
| 362 | ieee80211softmac_handle_disassoc(struct net_device * dev, |
| 363 | struct ieee80211_disassoc *disassoc) |
| 364 | { |
| 365 | struct ieee80211softmac_device *mac = ieee80211_priv(dev); |
| 366 | unsigned long flags; |
Johannes Berg | 48b2e4c | 2006-01-10 19:12:19 +0100 | [diff] [blame] | 367 | if (memcmp(disassoc->header.addr2, mac->associnfo.bssid, ETH_ALEN)) |
| 368 | return 0; |
| 369 | if (memcmp(disassoc->header.addr1, mac->dev->dev_addr, ETH_ALEN)) |
| 370 | return 0; |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 371 | dprintk(KERN_INFO PFX "got disassoc frame\n"); |
Johannes Berg | 2dd5080 | 2006-01-06 18:11:23 +0100 | [diff] [blame] | 372 | netif_carrier_off(dev); |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 373 | spin_lock_irqsave(&mac->lock, flags); |
| 374 | mac->associnfo.bssvalid = 0; |
| 375 | mac->associated = 0; |
Johannes Berg | d1469cf | 2006-01-10 15:47:06 +0100 | [diff] [blame] | 376 | schedule_work(&mac->associnfo.work); |
Johannes Berg | 370121e | 2006-01-04 16:32:16 +0100 | [diff] [blame] | 377 | spin_unlock_irqrestore(&mac->lock, flags); |
| 378 | |
| 379 | return 0; |
| 380 | } |
Johannes Berg | b6c7658 | 2006-01-31 19:49:42 +0100 | [diff] [blame] | 381 | |
| 382 | int |
| 383 | ieee80211softmac_handle_reassoc_req(struct net_device * dev, |
| 384 | struct ieee80211_reassoc_request * resp) |
| 385 | { |
| 386 | struct ieee80211softmac_device *mac = ieee80211_priv(dev); |
| 387 | struct ieee80211softmac_network *network; |
| 388 | |
Johannes Berg | b6c7658 | 2006-01-31 19:49:42 +0100 | [diff] [blame] | 389 | network = ieee80211softmac_get_network_by_bssid(mac, resp->header.addr3); |
| 390 | if (!network) { |
| 391 | dprintkl(KERN_INFO PFX "reassoc request from unknown network\n"); |
| 392 | return 0; |
| 393 | } |
| 394 | ieee80211softmac_assoc(mac, network); |
| 395 | return 0; |
| 396 | } |