[infiniband] Use "%#lx" as format specifier for queue pair numbers
[ipxe.git] / src / net / 80211 / net80211.c
1 /*
2 * The iPXE 802.11 MAC layer.
3 *
4 * Copyright (c) 2009 Joshua Oreman <oremanj@rwcr.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 as
8 * published by the Free Software Foundation; either version 2 of the
9 * License, or any later version.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19 * 02110-1301, USA.
20 */
21
22 FILE_LICENCE ( GPL2_OR_LATER );
23
24 #include <string.h>
25 #include <byteswap.h>
26 #include <stdlib.h>
27 #include <unistd.h>
28 #include <errno.h>
29 #include <ipxe/settings.h>
30 #include <ipxe/if_arp.h>
31 #include <ipxe/ethernet.h>
32 #include <ipxe/ieee80211.h>
33 #include <ipxe/netdevice.h>
34 #include <ipxe/net80211.h>
35 #include <ipxe/sec80211.h>
36 #include <ipxe/timer.h>
37 #include <ipxe/nap.h>
38 #include <ipxe/errortab.h>
39 #include <ipxe/net80211_err.h>
40
41 /** @file
42 *
43 * 802.11 device management
44 */
45
46 /** List of 802.11 devices */
47 static struct list_head net80211_devices = LIST_HEAD_INIT ( net80211_devices );
48
49 /** Set of device operations that does nothing */
50 static struct net80211_device_operations net80211_null_ops;
51
52 /** Information associated with a received management packet
53 *
54 * This is used to keep beacon signal strengths in a parallel queue to
55 * the beacons themselves.
56 */
57 struct net80211_rx_info {
58 int signal;
59 struct list_head list;
60 };
61
62 /** Context for a probe operation */
63 struct net80211_probe_ctx {
64 /** 802.11 device to probe on */
65 struct net80211_device *dev;
66
67 /** Value of keep_mgmt before probe was started */
68 int old_keep_mgmt;
69
70 /** If scanning actively, pointer to probe packet to send */
71 struct io_buffer *probe;
72
73 /** If non-"", the ESSID to limit ourselves to */
74 const char *essid;
75
76 /** Time probe was started */
77 u32 ticks_start;
78
79 /** Time last useful beacon was received */
80 u32 ticks_beacon;
81
82 /** Time channel was last changed */
83 u32 ticks_channel;
84
85 /** Time to stay on each channel */
86 u32 hop_time;
87
88 /** Channels to hop by when changing channel */
89 int hop_step;
90
91 /** List of best beacons for each network found so far */
92 struct list_head *beacons;
93 };
94
95 /** Context for the association task */
96 struct net80211_assoc_ctx {
97 /** Next authentication method to try using */
98 int method;
99
100 /** Time (in ticks) of the last sent association-related packet */
101 int last_packet;
102
103 /** Number of times we have tried sending it */
104 int times_tried;
105 };
106
107 /**
108 * Detect secure 802.11 network when security support is not available
109 *
110 * @return -ENOTSUP, always.
111 */
112 __weak int sec80211_detect ( struct io_buffer *iob __unused,
113 enum net80211_security_proto *secprot __unused,
114 enum net80211_crypto_alg *crypt __unused ) {
115 return -ENOTSUP;
116 }
117
118 /**
119 * @defgroup net80211_netdev Network device interface functions
120 * @{
121 */
122 static int net80211_netdev_open ( struct net_device *netdev );
123 static void net80211_netdev_close ( struct net_device *netdev );
124 static int net80211_netdev_transmit ( struct net_device *netdev,
125 struct io_buffer *iobuf );
126 static void net80211_netdev_poll ( struct net_device *netdev );
127 static void net80211_netdev_irq ( struct net_device *netdev, int enable );
128 /** @} */
129
130 /**
131 * @defgroup net80211_linklayer 802.11 link-layer protocol functions
132 * @{
133 */
134 static int net80211_ll_push ( struct net_device *netdev,
135 struct io_buffer *iobuf, const void *ll_dest,
136 const void *ll_source, uint16_t net_proto );
137 static int net80211_ll_pull ( struct net_device *netdev,
138 struct io_buffer *iobuf, const void **ll_dest,
139 const void **ll_source, uint16_t * net_proto,
140 unsigned int *flags );
141 /** @} */
142
143 /**
144 * @defgroup net80211_help 802.11 helper functions
145 * @{
146 */
147 static void net80211_add_channels ( struct net80211_device *dev, int start,
148 int len, int txpower );
149 static void net80211_filter_hw_channels ( struct net80211_device *dev );
150 static void net80211_set_rtscts_rate ( struct net80211_device *dev );
151 static int net80211_process_capab ( struct net80211_device *dev,
152 u16 capab );
153 static int net80211_process_ie ( struct net80211_device *dev,
154 union ieee80211_ie *ie, void *ie_end );
155 static union ieee80211_ie *
156 net80211_marshal_request_info ( struct net80211_device *dev,
157 union ieee80211_ie *ie );
158 /** @} */
159
160 /**
161 * @defgroup net80211_assoc_ll 802.11 association handling functions
162 * @{
163 */
164 static void net80211_step_associate ( struct net80211_device *dev );
165 static void net80211_handle_auth ( struct net80211_device *dev,
166 struct io_buffer *iob );
167 static void net80211_handle_assoc_reply ( struct net80211_device *dev,
168 struct io_buffer *iob );
169 static int net80211_send_disassoc ( struct net80211_device *dev, int reason,
170 int deauth );
171 static void net80211_handle_mgmt ( struct net80211_device *dev,
172 struct io_buffer *iob, int signal );
173 /** @} */
174
175 /**
176 * @defgroup net80211_frag 802.11 fragment handling functions
177 * @{
178 */
179 static void net80211_free_frags ( struct net80211_device *dev, int fcid );
180 static struct io_buffer *net80211_accum_frags ( struct net80211_device *dev,
181 int fcid, int nfrags, int size );
182 static void net80211_rx_frag ( struct net80211_device *dev,
183 struct io_buffer *iob, int signal );
184 /** @} */
185
186 /**
187 * @defgroup net80211_settings 802.11 settings handlers
188 * @{
189 */
190 static int net80211_check_settings_update ( void );
191
192 /** 802.11 settings applicator
193 *
194 * When the SSID is changed, this will cause any open devices to
195 * re-associate; when the encryption key is changed, we similarly
196 * update their state.
197 */
198 struct settings_applicator net80211_applicator __settings_applicator = {
199 .apply = net80211_check_settings_update,
200 };
201
202 /** The network name to associate with
203 *
204 * If this is blank, we scan for all networks and use the one with the
205 * greatest signal strength.
206 */
207 const struct setting net80211_ssid_setting __setting ( SETTING_NETDEV_EXTRA,
208 ssid ) = {
209 .name = "ssid",
210 .description = "Wireless SSID",
211 .type = &setting_type_string,
212 };
213
214 /** Whether to use active scanning
215 *
216 * In order to associate with a hidden SSID, it's necessary to use an
217 * active scan (send probe packets). If this setting is nonzero, an
218 * active scan on the 2.4GHz band will be used to associate.
219 */
220 const struct setting net80211_active_setting __setting ( SETTING_NETDEV_EXTRA,
221 active-scan ) = {
222 .name = "active-scan",
223 .description = "Actively scan for wireless networks",
224 .type = &setting_type_int8,
225 };
226
227 /** The cryptographic key to use
228 *
229 * For hex WEP keys, as is common, this must be entered using the
230 * normal iPXE method for entering hex settings; an ASCII string of
231 * hex characters will not behave as expected.
232 */
233 const struct setting net80211_key_setting __setting ( SETTING_NETDEV_EXTRA,
234 key ) = {
235 .name = "key",
236 .description = "Wireless encryption key",
237 .type = &setting_type_string,
238 };
239
240 /** @} */
241
242
243 /* ---------- net_device wrapper ---------- */
244
245 /**
246 * Open 802.11 device and start association
247 *
248 * @v netdev Wrapping network device
249 * @ret rc Return status code
250 *
251 * This sets up a default conservative set of channels for probing,
252 * and starts the auto-association task unless the @c
253 * NET80211_NO_ASSOC flag is set in the wrapped 802.11 device's @c
254 * state field.
255 */
256 static int net80211_netdev_open ( struct net_device *netdev )
257 {
258 struct net80211_device *dev = netdev->priv;
259 int rc = 0;
260
261 if ( dev->op == &net80211_null_ops )
262 return -EFAULT;
263
264 if ( dev->op->open )
265 rc = dev->op->open ( dev );
266
267 if ( rc < 0 )
268 return rc;
269
270 if ( ! ( dev->state & NET80211_NO_ASSOC ) )
271 net80211_autoassociate ( dev );
272
273 return 0;
274 }
275
276 /**
277 * Close 802.11 device
278 *
279 * @v netdev Wrapping network device.
280 *
281 * If the association task is running, this will stop it.
282 */
283 static void net80211_netdev_close ( struct net_device *netdev )
284 {
285 struct net80211_device *dev = netdev->priv;
286
287 if ( dev->state & NET80211_WORKING )
288 process_del ( &dev->proc_assoc );
289
290 /* Send disassociation frame to AP, to be polite */
291 if ( dev->state & NET80211_ASSOCIATED )
292 net80211_send_disassoc ( dev, IEEE80211_REASON_LEAVING, 0 );
293
294 if ( dev->handshaker && dev->handshaker->stop &&
295 dev->handshaker->started )
296 dev->handshaker->stop ( dev );
297
298 free ( dev->crypto );
299 free ( dev->handshaker );
300 dev->crypto = NULL;
301 dev->handshaker = NULL;
302
303 netdev_link_down ( netdev );
304 dev->state = 0;
305
306 if ( dev->op->close )
307 dev->op->close ( dev );
308 }
309
310 /**
311 * Transmit packet on 802.11 device
312 *
313 * @v netdev Wrapping network device
314 * @v iobuf I/O buffer
315 * @ret rc Return status code
316 *
317 * If encryption is enabled for the currently associated network, the
318 * packet will be encrypted prior to transmission.
319 */
320 static int net80211_netdev_transmit ( struct net_device *netdev,
321 struct io_buffer *iobuf )
322 {
323 struct net80211_device *dev = netdev->priv;
324 struct ieee80211_frame *hdr = iobuf->data;
325 int rc = -ENOSYS;
326
327 if ( dev->crypto && ! ( hdr->fc & IEEE80211_FC_PROTECTED ) &&
328 ( ( hdr->fc & IEEE80211_FC_TYPE ) == IEEE80211_TYPE_DATA ) ) {
329 struct io_buffer *niob = dev->crypto->encrypt ( dev->crypto,
330 iobuf );
331 if ( ! niob )
332 return -ENOMEM; /* only reason encryption could fail */
333
334 /* Free the non-encrypted iob */
335 netdev_tx_complete ( netdev, iobuf );
336
337 /* Transmit the encrypted iob; the Protected flag is
338 set, so we won't recurse into here again */
339 netdev_tx ( netdev, niob );
340
341 /* Don't transmit the freed packet */
342 return 0;
343 }
344
345 if ( dev->op->transmit )
346 rc = dev->op->transmit ( dev, iobuf );
347
348 return rc;
349 }
350
351 /**
352 * Poll 802.11 device for received packets and completed transmissions
353 *
354 * @v netdev Wrapping network device
355 */
356 static void net80211_netdev_poll ( struct net_device *netdev )
357 {
358 struct net80211_device *dev = netdev->priv;
359
360 if ( dev->op->poll )
361 dev->op->poll ( dev );
362 }
363
364 /**
365 * Enable or disable interrupts for 802.11 device
366 *
367 * @v netdev Wrapping network device
368 * @v enable Whether to enable interrupts
369 */
370 static void net80211_netdev_irq ( struct net_device *netdev, int enable )
371 {
372 struct net80211_device *dev = netdev->priv;
373
374 if ( dev->op->irq )
375 dev->op->irq ( dev, enable );
376 }
377
378 /** Network device operations for a wrapped 802.11 device */
379 static struct net_device_operations net80211_netdev_ops = {
380 .open = net80211_netdev_open,
381 .close = net80211_netdev_close,
382 .transmit = net80211_netdev_transmit,
383 .poll = net80211_netdev_poll,
384 .irq = net80211_netdev_irq,
385 };
386
387
388 /* ---------- 802.11 link-layer protocol ---------- */
389
390 /**
391 * Determine whether a transmission rate uses ERP/OFDM
392 *
393 * @v rate Rate in 100 kbps units
394 * @ret is_erp TRUE if the rate is an ERP/OFDM rate
395 *
396 * 802.11b supports rates of 1.0, 2.0, 5.5, and 11.0 Mbps; any other
397 * rate than these on the 2.4GHz spectrum is an ERP (802.11g) rate.
398 */
399 static inline int net80211_rate_is_erp ( u16 rate )
400 {
401 if ( rate == 10 || rate == 20 || rate == 55 || rate == 110 )
402 return 0;
403 return 1;
404 }
405
406
407 /**
408 * Calculate one frame's contribution to 802.11 duration field
409 *
410 * @v dev 802.11 device
411 * @v bytes Amount of data to calculate duration for
412 * @ret dur Duration field in microseconds
413 *
414 * To avoid multiple stations attempting to transmit at once, 802.11
415 * provides that every packet shall include a duration field
416 * specifying a length of time for which the wireless medium will be
417 * reserved after it is transmitted. The duration is measured in
418 * microseconds and is calculated with respect to the current
419 * physical-layer parameters of the 802.11 device.
420 *
421 * For an unfragmented data or management frame, or the last fragment
422 * of a fragmented frame, the duration captures only the 10 data bytes
423 * of one ACK; call once with bytes = 10.
424 *
425 * For a fragment of a data or management rame that will be followed
426 * by more fragments, the duration captures an ACK, the following
427 * fragment, and its ACK; add the results of three calls, two with
428 * bytes = 10 and one with bytes set to the next fragment's size.
429 *
430 * For an RTS control frame, the duration captures the responding CTS,
431 * the frame being sent, and its ACK; add the results of three calls,
432 * two with bytes = 10 and one with bytes set to the next frame's size
433 * (assuming unfragmented).
434 *
435 * For a CTS-to-self control frame, the duration captures the frame
436 * being protected and its ACK; add the results of two calls, one with
437 * bytes = 10 and one with bytes set to the next frame's size.
438 *
439 * No other frame types are currently supported by iPXE.
440 */
441 u16 net80211_duration ( struct net80211_device *dev, int bytes, u16 rate )
442 {
443 struct net80211_channel *chan = &dev->channels[dev->channel];
444 u32 kbps = rate * 100;
445
446 if ( chan->band == NET80211_BAND_5GHZ || net80211_rate_is_erp ( rate ) ) {
447 /* OFDM encoding (802.11a/g) */
448 int bits_per_symbol = ( kbps * 4 ) / 1000; /* 4us/symbol */
449 int bits = 22 + ( bytes << 3 ); /* 22-bit PLCP */
450 int symbols = ( bits + bits_per_symbol - 1 ) / bits_per_symbol;
451
452 return 16 + 20 + ( symbols * 4 ); /* 16us SIFS, 20us preamble */
453 } else {
454 /* CCK encoding (802.11b) */
455 int phy_time = 144 + 48; /* preamble + PLCP */
456 int bits = bytes << 3;
457 int data_time = ( bits * 1000 + kbps - 1 ) / kbps;
458
459 if ( dev->phy_flags & NET80211_PHY_USE_SHORT_PREAMBLE )
460 phy_time >>= 1;
461
462 return 10 + phy_time + data_time; /* 10us SIFS */
463 }
464 }
465
466 /**
467 * Add 802.11 link-layer header
468 *
469 * @v netdev Wrapping network device
470 * @v iobuf I/O buffer
471 * @v ll_dest Link-layer destination address
472 * @v ll_source Link-layer source address
473 * @v net_proto Network-layer protocol, in network byte order
474 * @ret rc Return status code
475 *
476 * This adds both the 802.11 frame header and the 802.2 LLC/SNAP
477 * header used on data packets.
478 *
479 * We also check here for state of the link that would make it invalid
480 * to send a data packet; every data packet must pass through here,
481 * and no non-data packet (e.g. management frame) should.
482 */
483 static int net80211_ll_push ( struct net_device *netdev,
484 struct io_buffer *iobuf, const void *ll_dest,
485 const void *ll_source, uint16_t net_proto )
486 {
487 struct net80211_device *dev = netdev->priv;
488 struct ieee80211_frame *hdr = iob_push ( iobuf,
489 IEEE80211_LLC_HEADER_LEN +
490 IEEE80211_TYP_FRAME_HEADER_LEN );
491 struct ieee80211_llc_snap_header *lhdr =
492 ( void * ) hdr + IEEE80211_TYP_FRAME_HEADER_LEN;
493
494 /* We can't send data packets if we're not associated. */
495 if ( ! ( dev->state & NET80211_ASSOCIATED ) ) {
496 if ( dev->assoc_rc )
497 return dev->assoc_rc;
498 return -ENETUNREACH;
499 }
500
501 hdr->fc = IEEE80211_THIS_VERSION | IEEE80211_TYPE_DATA |
502 IEEE80211_STYPE_DATA | IEEE80211_FC_TODS;
503
504 /* We don't send fragmented frames, so duration is the time
505 for an SIFS + 10-byte ACK. */
506 hdr->duration = net80211_duration ( dev, 10, dev->rates[dev->rate] );
507
508 memcpy ( hdr->addr1, dev->bssid, ETH_ALEN );
509 memcpy ( hdr->addr2, ll_source, ETH_ALEN );
510 memcpy ( hdr->addr3, ll_dest, ETH_ALEN );
511
512 hdr->seq = IEEE80211_MAKESEQ ( ++dev->last_tx_seqnr, 0 );
513
514 lhdr->dsap = IEEE80211_LLC_DSAP;
515 lhdr->ssap = IEEE80211_LLC_SSAP;
516 lhdr->ctrl = IEEE80211_LLC_CTRL;
517 memset ( lhdr->oui, 0x00, 3 );
518 lhdr->ethertype = net_proto;
519
520 return 0;
521 }
522
523 /**
524 * Remove 802.11 link-layer header
525 *
526 * @v netdev Wrapping network device
527 * @v iobuf I/O buffer
528 * @ret ll_dest Link-layer destination address
529 * @ret ll_source Link-layer source
530 * @ret net_proto Network-layer protocol, in network byte order
531 * @ret flags Packet flags
532 * @ret rc Return status code
533 *
534 * This expects and removes both the 802.11 frame header and the 802.2
535 * LLC/SNAP header that are used on data packets.
536 */
537 static int net80211_ll_pull ( struct net_device *netdev __unused,
538 struct io_buffer *iobuf,
539 const void **ll_dest, const void **ll_source,
540 uint16_t * net_proto, unsigned int *flags )
541 {
542 struct ieee80211_frame *hdr = iobuf->data;
543 struct ieee80211_llc_snap_header *lhdr =
544 ( void * ) hdr + IEEE80211_TYP_FRAME_HEADER_LEN;
545
546 /* Bunch of sanity checks */
547 if ( iob_len ( iobuf ) < IEEE80211_TYP_FRAME_HEADER_LEN +
548 IEEE80211_LLC_HEADER_LEN ) {
549 DBGC ( netdev->priv, "802.11 %p packet too short (%zd bytes)\n",
550 netdev->priv, iob_len ( iobuf ) );
551 return -EINVAL_PKT_TOO_SHORT;
552 }
553
554 if ( ( hdr->fc & IEEE80211_FC_VERSION ) != IEEE80211_THIS_VERSION ) {
555 DBGC ( netdev->priv, "802.11 %p packet invalid version %04x\n",
556 netdev->priv, hdr->fc & IEEE80211_FC_VERSION );
557 return -EINVAL_PKT_VERSION;
558 }
559
560 if ( ( hdr->fc & IEEE80211_FC_TYPE ) != IEEE80211_TYPE_DATA ||
561 ( hdr->fc & IEEE80211_FC_SUBTYPE ) != IEEE80211_STYPE_DATA ) {
562 DBGC ( netdev->priv, "802.11 %p packet not data/data (fc=%04x)\n",
563 netdev->priv, hdr->fc );
564 return -EINVAL_PKT_NOT_DATA;
565 }
566
567 if ( ( hdr->fc & ( IEEE80211_FC_TODS | IEEE80211_FC_FROMDS ) ) !=
568 IEEE80211_FC_FROMDS ) {
569 DBGC ( netdev->priv, "802.11 %p packet not from DS (fc=%04x)\n",
570 netdev->priv, hdr->fc );
571 return -EINVAL_PKT_NOT_FROMDS;
572 }
573
574 if ( lhdr->dsap != IEEE80211_LLC_DSAP || lhdr->ssap != IEEE80211_LLC_SSAP ||
575 lhdr->ctrl != IEEE80211_LLC_CTRL || lhdr->oui[0] || lhdr->oui[1] ||
576 lhdr->oui[2] ) {
577 DBGC ( netdev->priv, "802.11 %p LLC header is not plain EtherType "
578 "encapsulator: %02x->%02x [%02x] %02x:%02x:%02x %04x\n",
579 netdev->priv, lhdr->dsap, lhdr->ssap, lhdr->ctrl,
580 lhdr->oui[0], lhdr->oui[1], lhdr->oui[2], lhdr->ethertype );
581 return -EINVAL_PKT_LLC_HEADER;
582 }
583
584 iob_pull ( iobuf, sizeof ( *hdr ) + sizeof ( *lhdr ) );
585
586 *ll_dest = hdr->addr1;
587 *ll_source = hdr->addr3;
588 *net_proto = lhdr->ethertype;
589 *flags = ( ( is_multicast_ether_addr ( hdr->addr1 ) ?
590 LL_MULTICAST : 0 ) |
591 ( is_broadcast_ether_addr ( hdr->addr1 ) ?
592 LL_BROADCAST : 0 ) );
593 return 0;
594 }
595
596 /** 802.11 link-layer protocol */
597 static struct ll_protocol net80211_ll_protocol __ll_protocol = {
598 .name = "802.11",
599 .push = net80211_ll_push,
600 .pull = net80211_ll_pull,
601 .init_addr = eth_init_addr,
602 .ntoa = eth_ntoa,
603 .mc_hash = eth_mc_hash,
604 .eth_addr = eth_eth_addr,
605 .eui64 = eth_eui64,
606 .ll_proto = htons ( ARPHRD_ETHER ), /* "encapsulated Ethernet" */
607 .hw_addr_len = ETH_ALEN,
608 .ll_addr_len = ETH_ALEN,
609 .ll_header_len = IEEE80211_TYP_FRAME_HEADER_LEN +
610 IEEE80211_LLC_HEADER_LEN,
611 };
612
613
614 /* ---------- 802.11 network management API ---------- */
615
616 /**
617 * Get 802.11 device from wrapping network device
618 *
619 * @v netdev Wrapping network device
620 * @ret dev 802.11 device wrapped by network device, or NULL
621 *
622 * Returns NULL if the network device does not wrap an 802.11 device.
623 */
624 struct net80211_device * net80211_get ( struct net_device *netdev )
625 {
626 struct net80211_device *dev;
627
628 list_for_each_entry ( dev, &net80211_devices, list ) {
629 if ( netdev->priv == dev )
630 return netdev->priv;
631 }
632
633 return NULL;
634 }
635
636 /**
637 * Set state of 802.11 device keeping management frames
638 *
639 * @v dev 802.11 device
640 * @v enable Whether to keep management frames
641 * @ret oldenab Whether management frames were enabled before this call
642 *
643 * If enable is TRUE, beacon, probe, and action frames will be kept
644 * and may be retrieved by calling net80211_mgmt_dequeue().
645 */
646 int net80211_keep_mgmt ( struct net80211_device *dev, int enable )
647 {
648 int oldenab = dev->keep_mgmt;
649
650 dev->keep_mgmt = enable;
651 return oldenab;
652 }
653
654 /**
655 * Get 802.11 management frame
656 *
657 * @v dev 802.11 device
658 * @ret signal Signal strength of returned management frame
659 * @ret iob I/O buffer, or NULL if no management frame is queued
660 *
661 * Frames will only be returned by this function if
662 * net80211_keep_mgmt() has been previously called with enable set to
663 * TRUE.
664 *
665 * The calling function takes ownership of the returned I/O buffer.
666 */
667 struct io_buffer * net80211_mgmt_dequeue ( struct net80211_device *dev,
668 int *signal )
669 {
670 struct io_buffer *iobuf;
671 struct net80211_rx_info *rxi;
672
673 list_for_each_entry ( rxi, &dev->mgmt_info_queue, list ) {
674 list_del ( &rxi->list );
675 if ( signal )
676 *signal = rxi->signal;
677 free ( rxi );
678
679 assert ( ! list_empty ( &dev->mgmt_queue ) );
680 iobuf = list_first_entry ( &dev->mgmt_queue, struct io_buffer,
681 list );
682 list_del ( &iobuf->list );
683 return iobuf;
684 }
685
686 return NULL;
687 }
688
689 /**
690 * Transmit 802.11 management frame
691 *
692 * @v dev 802.11 device
693 * @v fc Frame Control flags for management frame
694 * @v dest Destination access point
695 * @v iob I/O buffer
696 * @ret rc Return status code
697 *
698 * The @a fc argument must contain at least an IEEE 802.11 management
699 * subtype number (e.g. IEEE80211_STYPE_PROBE_REQ). If it contains
700 * IEEE80211_FC_PROTECTED, the frame will be encrypted prior to
701 * transmission.
702 *
703 * It is required that @a iob have at least 24 bytes of headroom
704 * reserved before its data start.
705 */
706 int net80211_tx_mgmt ( struct net80211_device *dev, u16 fc, u8 dest[6],
707 struct io_buffer *iob )
708 {
709 struct ieee80211_frame *hdr = iob_push ( iob,
710 IEEE80211_TYP_FRAME_HEADER_LEN );
711
712 hdr->fc = IEEE80211_THIS_VERSION | IEEE80211_TYPE_MGMT |
713 ( fc & ~IEEE80211_FC_PROTECTED );
714 hdr->duration = net80211_duration ( dev, 10, dev->rates[dev->rate] );
715 hdr->seq = IEEE80211_MAKESEQ ( ++dev->last_tx_seqnr, 0 );
716
717 memcpy ( hdr->addr1, dest, ETH_ALEN ); /* DA = RA */
718 memcpy ( hdr->addr2, dev->netdev->ll_addr, ETH_ALEN ); /* SA = TA */
719 memcpy ( hdr->addr3, dest, ETH_ALEN ); /* BSSID */
720
721 if ( fc & IEEE80211_FC_PROTECTED ) {
722 if ( ! dev->crypto )
723 return -EINVAL_CRYPTO_REQUEST;
724
725 struct io_buffer *eiob = dev->crypto->encrypt ( dev->crypto,
726 iob );
727 free_iob ( iob );
728 iob = eiob;
729 }
730
731 return netdev_tx ( dev->netdev, iob );
732 }
733
734
735 /* ---------- Driver API ---------- */
736
737 /** 802.11 association process descriptor */
738 static struct process_descriptor net80211_process_desc =
739 PROC_DESC ( struct net80211_device, proc_assoc,
740 net80211_step_associate );
741
742 /**
743 * Allocate 802.11 device
744 *
745 * @v priv_size Size of driver-private allocation area
746 * @ret dev Newly allocated 802.11 device
747 *
748 * This function allocates a net_device with space in its private area
749 * for both the net80211_device it will wrap and the driver-private
750 * data space requested. It initializes the link-layer-specific parts
751 * of the net_device, and links the net80211_device to the net_device
752 * appropriately.
753 */
754 struct net80211_device * net80211_alloc ( size_t priv_size )
755 {
756 struct net80211_device *dev;
757 struct net_device *netdev =
758 alloc_netdev ( sizeof ( *dev ) + priv_size );
759
760 if ( ! netdev )
761 return NULL;
762
763 netdev->ll_protocol = &net80211_ll_protocol;
764 netdev->ll_broadcast = eth_broadcast;
765 netdev->max_pkt_len = IEEE80211_MAX_DATA_LEN;
766 netdev_init ( netdev, &net80211_netdev_ops );
767
768 dev = netdev->priv;
769 dev->netdev = netdev;
770 dev->priv = ( u8 * ) dev + sizeof ( *dev );
771 dev->op = &net80211_null_ops;
772
773 process_init_stopped ( &dev->proc_assoc, &net80211_process_desc,
774 &netdev->refcnt );
775 INIT_LIST_HEAD ( &dev->mgmt_queue );
776 INIT_LIST_HEAD ( &dev->mgmt_info_queue );
777
778 return dev;
779 }
780
781 /**
782 * Register 802.11 device with network stack
783 *
784 * @v dev 802.11 device
785 * @v ops 802.11 device operations
786 * @v hw 802.11 hardware information
787 *
788 * This also registers the wrapping net_device with the higher network
789 * layers.
790 */
791 int net80211_register ( struct net80211_device *dev,
792 struct net80211_device_operations *ops,
793 struct net80211_hw_info *hw )
794 {
795 dev->op = ops;
796 dev->hw = malloc ( sizeof ( *hw ) );
797 if ( ! dev->hw )
798 return -ENOMEM;
799
800 memcpy ( dev->hw, hw, sizeof ( *hw ) );
801 memcpy ( dev->netdev->hw_addr, hw->hwaddr, ETH_ALEN );
802
803 /* Set some sensible channel defaults for driver's open() function */
804 memcpy ( dev->channels, dev->hw->channels,
805 NET80211_MAX_CHANNELS * sizeof ( dev->channels[0] ) );
806 dev->channel = 0;
807
808 /* Mark device as not supporting interrupts, if applicable */
809 if ( ! ops->irq )
810 dev->netdev->state |= NETDEV_IRQ_UNSUPPORTED;
811
812 list_add_tail ( &dev->list, &net80211_devices );
813 return register_netdev ( dev->netdev );
814 }
815
816 /**
817 * Unregister 802.11 device from network stack
818 *
819 * @v dev 802.11 device
820 *
821 * After this call, the device operations are cleared so that they
822 * will not be called.
823 */
824 void net80211_unregister ( struct net80211_device *dev )
825 {
826 unregister_netdev ( dev->netdev );
827 list_del ( &dev->list );
828 dev->op = &net80211_null_ops;
829 }
830
831 /**
832 * Free 802.11 device
833 *
834 * @v dev 802.11 device
835 *
836 * The device should be unregistered before this function is called.
837 */
838 void net80211_free ( struct net80211_device *dev )
839 {
840 free ( dev->hw );
841 rc80211_free ( dev->rctl );
842 netdev_nullify ( dev->netdev );
843 netdev_put ( dev->netdev );
844 }
845
846
847 /* ---------- 802.11 network management workhorse code ---------- */
848
849 /**
850 * Set state of 802.11 device
851 *
852 * @v dev 802.11 device
853 * @v clear Bitmask of flags to clear
854 * @v set Bitmask of flags to set
855 * @v status Status or reason code for most recent operation
856 *
857 * If @a status represents a reason code, it should be OR'ed with
858 * NET80211_IS_REASON.
859 *
860 * Clearing authentication also clears association; clearing
861 * association also clears security handshaking state. Clearing
862 * association removes the link-up flag from the wrapping net_device,
863 * but setting it does not automatically set the flag; that is left to
864 * the judgment of higher-level code.
865 */
866 static inline void net80211_set_state ( struct net80211_device *dev,
867 short clear, short set,
868 u16 status )
869 {
870 /* The conditions in this function are deliberately formulated
871 to be decidable at compile-time in most cases. Since clear
872 and set are generally passed as constants, the body of this
873 function can be reduced down to a few statements by the
874 compiler. */
875
876 const int statmsk = NET80211_STATUS_MASK | NET80211_IS_REASON;
877
878 if ( clear & NET80211_PROBED )
879 clear |= NET80211_AUTHENTICATED;
880
881 if ( clear & NET80211_AUTHENTICATED )
882 clear |= NET80211_ASSOCIATED;
883
884 if ( clear & NET80211_ASSOCIATED )
885 clear |= NET80211_CRYPTO_SYNCED;
886
887 dev->state = ( dev->state & ~clear ) | set;
888 dev->state = ( dev->state & ~statmsk ) | ( status & statmsk );
889
890 if ( clear & NET80211_ASSOCIATED )
891 netdev_link_down ( dev->netdev );
892
893 if ( ( clear | set ) & NET80211_ASSOCIATED )
894 dev->op->config ( dev, NET80211_CFG_ASSOC );
895
896 if ( status != 0 ) {
897 if ( status & NET80211_IS_REASON )
898 dev->assoc_rc = -E80211_REASON ( status );
899 else
900 dev->assoc_rc = -E80211_STATUS ( status );
901 netdev_link_err ( dev->netdev, dev->assoc_rc );
902 }
903 }
904
905 /**
906 * Add channels to 802.11 device
907 *
908 * @v dev 802.11 device
909 * @v start First channel number to add
910 * @v len Number of channels to add
911 * @v txpower TX power (dBm) to allow on added channels
912 *
913 * To replace the current list of channels instead of adding to it,
914 * set the nr_channels field of the 802.11 device to 0 before calling
915 * this function.
916 */
917 static void net80211_add_channels ( struct net80211_device *dev, int start,
918 int len, int txpower )
919 {
920 int i, chan = start;
921
922 for ( i = dev->nr_channels; len-- && i < NET80211_MAX_CHANNELS; i++ ) {
923 dev->channels[i].channel_nr = chan;
924 dev->channels[i].maxpower = txpower;
925 dev->channels[i].hw_value = 0;
926
927 if ( chan >= 1 && chan <= 14 ) {
928 dev->channels[i].band = NET80211_BAND_2GHZ;
929 if ( chan == 14 )
930 dev->channels[i].center_freq = 2484;
931 else
932 dev->channels[i].center_freq = 2407 + 5 * chan;
933 chan++;
934 } else {
935 dev->channels[i].band = NET80211_BAND_5GHZ;
936 dev->channels[i].center_freq = 5000 + 5 * chan;
937 chan += 4;
938 }
939 }
940
941 dev->nr_channels = i;
942 }
943
944 /**
945 * Filter 802.11 device channels for hardware capabilities
946 *
947 * @v dev 802.11 device
948 *
949 * Hardware may support fewer channels than regulatory restrictions
950 * allow; this function filters out channels in dev->channels that are
951 * not supported by the hardware list in dev->hwinfo. It also copies
952 * over the net80211_channel::hw_value and limits maximum TX power
953 * appropriately.
954 *
955 * Channels are matched based on center frequency, ignoring band and
956 * channel number.
957 *
958 * If the driver specifies no supported channels, the effect will be
959 * as though all were supported.
960 */
961 static void net80211_filter_hw_channels ( struct net80211_device *dev )
962 {
963 int delta = 0, i = 0;
964 int old_freq = dev->channels[dev->channel].center_freq;
965 struct net80211_channel *chan, *hwchan;
966
967 if ( ! dev->hw->nr_channels )
968 return;
969
970 dev->channel = 0;
971 for ( chan = dev->channels; chan < dev->channels + dev->nr_channels;
972 chan++, i++ ) {
973 int ok = 0;
974 for ( hwchan = dev->hw->channels;
975 hwchan < dev->hw->channels + dev->hw->nr_channels;
976 hwchan++ ) {
977 if ( hwchan->center_freq == chan->center_freq ) {
978 ok = 1;
979 break;
980 }
981 }
982
983 if ( ! ok )
984 delta++;
985 else {
986 chan->hw_value = hwchan->hw_value;
987 if ( hwchan->maxpower != 0 &&
988 chan->maxpower > hwchan->maxpower )
989 chan->maxpower = hwchan->maxpower;
990 if ( old_freq == chan->center_freq )
991 dev->channel = i - delta;
992 if ( delta )
993 chan[-delta] = *chan;
994 }
995 }
996
997 dev->nr_channels -= delta;
998
999 if ( dev->channels[dev->channel].center_freq != old_freq )
1000 dev->op->config ( dev, NET80211_CFG_CHANNEL );
1001 }
1002
1003 /**
1004 * Update 802.11 device state to reflect received capabilities field
1005 *
1006 * @v dev 802.11 device
1007 * @v capab Capabilities field in beacon, probe, or association frame
1008 * @ret rc Return status code
1009 */
1010 static int net80211_process_capab ( struct net80211_device *dev,
1011 u16 capab )
1012 {
1013 u16 old_phy = dev->phy_flags;
1014
1015 if ( ( capab & ( IEEE80211_CAPAB_MANAGED | IEEE80211_CAPAB_ADHOC ) ) !=
1016 IEEE80211_CAPAB_MANAGED ) {
1017 DBGC ( dev, "802.11 %p cannot handle IBSS network\n", dev );
1018 return -ENOSYS;
1019 }
1020
1021 dev->phy_flags &= ~( NET80211_PHY_USE_SHORT_PREAMBLE |
1022 NET80211_PHY_USE_SHORT_SLOT );
1023
1024 if ( capab & IEEE80211_CAPAB_SHORT_PMBL )
1025 dev->phy_flags |= NET80211_PHY_USE_SHORT_PREAMBLE;
1026
1027 if ( capab & IEEE80211_CAPAB_SHORT_SLOT )
1028 dev->phy_flags |= NET80211_PHY_USE_SHORT_SLOT;
1029
1030 if ( old_phy != dev->phy_flags )
1031 dev->op->config ( dev, NET80211_CFG_PHY_PARAMS );
1032
1033 return 0;
1034 }
1035
1036 /**
1037 * Update 802.11 device state to reflect received information elements
1038 *
1039 * @v dev 802.11 device
1040 * @v ie Pointer to first information element
1041 * @v ie_end Pointer to tail of packet I/O buffer
1042 * @ret rc Return status code
1043 */
1044 static int net80211_process_ie ( struct net80211_device *dev,
1045 union ieee80211_ie *ie, void *ie_end )
1046 {
1047 u16 old_rate = dev->rates[dev->rate];
1048 u16 old_phy = dev->phy_flags;
1049 int have_rates = 0, i;
1050 int ds_channel = 0;
1051 int changed = 0;
1052 int band = dev->channels[dev->channel].band;
1053
1054 if ( ! ieee80211_ie_bound ( ie, ie_end ) )
1055 return 0;
1056
1057 for ( ; ie; ie = ieee80211_next_ie ( ie, ie_end ) ) {
1058 switch ( ie->id ) {
1059 case IEEE80211_IE_SSID:
1060 if ( ie->len <= 32 ) {
1061 memcpy ( dev->essid, ie->ssid, ie->len );
1062 dev->essid[ie->len] = 0;
1063 }
1064 break;
1065
1066 case IEEE80211_IE_RATES:
1067 case IEEE80211_IE_EXT_RATES:
1068 if ( ! have_rates ) {
1069 dev->nr_rates = 0;
1070 dev->basic_rates = 0;
1071 have_rates = 1;
1072 }
1073 for ( i = 0; i < ie->len &&
1074 dev->nr_rates < NET80211_MAX_RATES; i++ ) {
1075 u8 rid = ie->rates[i];
1076 u16 rate = ( rid & 0x7f ) * 5;
1077
1078 if ( rid & 0x80 )
1079 dev->basic_rates |=
1080 ( 1 << dev->nr_rates );
1081
1082 dev->rates[dev->nr_rates++] = rate;
1083 }
1084
1085 break;
1086
1087 case IEEE80211_IE_DS_PARAM:
1088 if ( dev->channel < dev->nr_channels && ds_channel ==
1089 dev->channels[dev->channel].channel_nr )
1090 break;
1091 ds_channel = ie->ds_param.current_channel;
1092 net80211_change_channel ( dev, ds_channel );
1093 break;
1094
1095 case IEEE80211_IE_COUNTRY:
1096 dev->nr_channels = 0;
1097
1098 DBGC ( dev, "802.11 %p setting country regulations "
1099 "for %c%c\n", dev, ie->country.name[0],
1100 ie->country.name[1] );
1101 for ( i = 0; i < ( ie->len - 3 ) / 3; i++ ) {
1102 union ieee80211_ie_country_triplet *t =
1103 &ie->country.triplet[i];
1104 if ( t->first > 200 ) {
1105 DBGC ( dev, "802.11 %p ignoring regulatory "
1106 "extension information\n", dev );
1107 } else {
1108 net80211_add_channels ( dev,
1109 t->band.first_channel,
1110 t->band.nr_channels,
1111 t->band.max_txpower );
1112 }
1113 }
1114 net80211_filter_hw_channels ( dev );
1115 break;
1116
1117 case IEEE80211_IE_ERP_INFO:
1118 dev->phy_flags &= ~( NET80211_PHY_USE_PROTECTION |
1119 NET80211_PHY_USE_SHORT_PREAMBLE );
1120 if ( ie->erp_info & IEEE80211_ERP_USE_PROTECTION )
1121 dev->phy_flags |= NET80211_PHY_USE_PROTECTION;
1122 if ( ! ( ie->erp_info & IEEE80211_ERP_BARKER_LONG ) )
1123 dev->phy_flags |= NET80211_PHY_USE_SHORT_PREAMBLE;
1124 break;
1125 }
1126 }
1127
1128 if ( have_rates ) {
1129 /* Allow only those rates that are also supported by
1130 the hardware. */
1131 int delta = 0, j;
1132
1133 dev->rate = 0;
1134 for ( i = 0; i < dev->nr_rates; i++ ) {
1135 int ok = 0;
1136 for ( j = 0; j < dev->hw->nr_rates[band]; j++ ) {
1137 if ( dev->hw->rates[band][j] == dev->rates[i] ){
1138 ok = 1;
1139 break;
1140 }
1141 }
1142
1143 if ( ! ok )
1144 delta++;
1145 else {
1146 dev->rates[i - delta] = dev->rates[i];
1147 if ( old_rate == dev->rates[i] )
1148 dev->rate = i - delta;
1149 }
1150 }
1151
1152 dev->nr_rates -= delta;
1153
1154 /* Sort available rates - sorted subclumps tend to already
1155 exist, so insertion sort works well. */
1156 for ( i = 1; i < dev->nr_rates; i++ ) {
1157 u16 rate = dev->rates[i];
1158 u32 tmp, br, mask;
1159
1160 for ( j = i - 1; j >= 0 && dev->rates[j] >= rate; j-- )
1161 dev->rates[j + 1] = dev->rates[j];
1162 dev->rates[j + 1] = rate;
1163
1164 /* Adjust basic_rates to match by rotating the
1165 bits from bit j+1 to bit i left one position. */
1166 mask = ( ( 1 << i ) - 1 ) & ~( ( 1 << ( j + 1 ) ) - 1 );
1167 br = dev->basic_rates;
1168 tmp = br & ( 1 << i );
1169 br = ( br & ~( mask | tmp ) ) | ( ( br & mask ) << 1 );
1170 br |= ( tmp >> ( i - j - 1 ) );
1171 dev->basic_rates = br;
1172 }
1173
1174 net80211_set_rtscts_rate ( dev );
1175
1176 if ( dev->rates[dev->rate] != old_rate )
1177 changed |= NET80211_CFG_RATE;
1178 }
1179
1180 if ( dev->hw->flags & NET80211_HW_NO_SHORT_PREAMBLE )
1181 dev->phy_flags &= ~NET80211_PHY_USE_SHORT_PREAMBLE;
1182 if ( dev->hw->flags & NET80211_HW_NO_SHORT_SLOT )
1183 dev->phy_flags &= ~NET80211_PHY_USE_SHORT_SLOT;
1184
1185 if ( old_phy != dev->phy_flags )
1186 changed |= NET80211_CFG_PHY_PARAMS;
1187
1188 if ( changed )
1189 dev->op->config ( dev, changed );
1190
1191 return 0;
1192 }
1193
1194 /**
1195 * Create information elements for outgoing probe or association packet
1196 *
1197 * @v dev 802.11 device
1198 * @v ie Pointer to start of information element area
1199 * @ret next_ie Pointer to first byte after added information elements
1200 */
1201 static union ieee80211_ie *
1202 net80211_marshal_request_info ( struct net80211_device *dev,
1203 union ieee80211_ie *ie )
1204 {
1205 int i;
1206
1207 ie->id = IEEE80211_IE_SSID;
1208 ie->len = strlen ( dev->essid );
1209 memcpy ( ie->ssid, dev->essid, ie->len );
1210
1211 ie = ieee80211_next_ie ( ie, NULL );
1212
1213 ie->id = IEEE80211_IE_RATES;
1214 ie->len = dev->nr_rates;
1215 if ( ie->len > 8 )
1216 ie->len = 8;
1217
1218 for ( i = 0; i < ie->len; i++ ) {
1219 ie->rates[i] = dev->rates[i] / 5;
1220 if ( dev->basic_rates & ( 1 << i ) )
1221 ie->rates[i] |= 0x80;
1222 }
1223
1224 ie = ieee80211_next_ie ( ie, NULL );
1225
1226 if ( dev->rsn_ie && dev->rsn_ie->id == IEEE80211_IE_RSN ) {
1227 memcpy ( ie, dev->rsn_ie, dev->rsn_ie->len + 2 );
1228 ie = ieee80211_next_ie ( ie, NULL );
1229 }
1230
1231 if ( dev->nr_rates > 8 ) {
1232 /* 802.11 requires we use an Extended Basic Rates IE
1233 for the rates beyond the eighth. */
1234
1235 ie->id = IEEE80211_IE_EXT_RATES;
1236 ie->len = dev->nr_rates - 8;
1237
1238 for ( ; i < dev->nr_rates; i++ ) {
1239 ie->rates[i - 8] = dev->rates[i] / 5;
1240 if ( dev->basic_rates & ( 1 << i ) )
1241 ie->rates[i - 8] |= 0x80;
1242 }
1243
1244 ie = ieee80211_next_ie ( ie, NULL );
1245 }
1246
1247 if ( dev->rsn_ie && dev->rsn_ie->id == IEEE80211_IE_VENDOR ) {
1248 memcpy ( ie, dev->rsn_ie, dev->rsn_ie->len + 2 );
1249 ie = ieee80211_next_ie ( ie, NULL );
1250 }
1251
1252 return ie;
1253 }
1254
1255 /** Seconds to wait after finding a network, to possibly find better APs for it
1256 *
1257 * This is used when a specific SSID to scan for is specified.
1258 */
1259 #define NET80211_PROBE_GATHER 1
1260
1261 /** Seconds to wait after finding a network, to possibly find other networks
1262 *
1263 * This is used when an empty SSID is specified, to scan for all
1264 * networks.
1265 */
1266 #define NET80211_PROBE_GATHER_ALL 2
1267
1268 /** Seconds to allow a probe to take if no network has been found */
1269 #define NET80211_PROBE_TIMEOUT 6
1270
1271 /**
1272 * Begin probe of 802.11 networks
1273 *
1274 * @v dev 802.11 device
1275 * @v essid SSID to probe for, or "" to accept any (may not be NULL)
1276 * @v active Whether to use active scanning
1277 * @ret ctx Probe context
1278 *
1279 * Active scanning may only be used on channels 1-11 in the 2.4GHz
1280 * band, due to iPXE's lack of a complete regulatory database. If
1281 * active scanning is used, probe packets will be sent on each
1282 * channel; this can allow association with hidden-SSID networks if
1283 * the SSID is properly specified.
1284 *
1285 * A @c NULL return indicates an out-of-memory condition.
1286 *
1287 * The returned context must be periodically passed to
1288 * net80211_probe_step() until that function returns zero.
1289 */
1290 struct net80211_probe_ctx * net80211_probe_start ( struct net80211_device *dev,
1291 const char *essid,
1292 int active )
1293 {
1294 struct net80211_probe_ctx *ctx = zalloc ( sizeof ( *ctx ) );
1295
1296 if ( ! ctx )
1297 return NULL;
1298
1299 assert ( netdev_is_open ( dev->netdev ) );
1300
1301 ctx->dev = dev;
1302 ctx->old_keep_mgmt = net80211_keep_mgmt ( dev, 1 );
1303 ctx->essid = essid;
1304 if ( dev->essid != ctx->essid )
1305 strcpy ( dev->essid, ctx->essid );
1306
1307 if ( active ) {
1308 struct ieee80211_probe_req *probe_req;
1309 union ieee80211_ie *ie;
1310
1311 ctx->probe = alloc_iob ( 128 );
1312 iob_reserve ( ctx->probe, IEEE80211_TYP_FRAME_HEADER_LEN );
1313 probe_req = ctx->probe->data;
1314
1315 ie = net80211_marshal_request_info ( dev,
1316 probe_req->info_element );
1317
1318 iob_put ( ctx->probe, ( void * ) ie - ctx->probe->data );
1319 }
1320
1321 ctx->ticks_start = currticks();
1322 ctx->ticks_beacon = 0;
1323 ctx->ticks_channel = currticks();
1324 ctx->hop_time = ticks_per_sec() / ( active ? 2 : 6 );
1325
1326 /*
1327 * Channels on 2.4GHz overlap, and the most commonly used
1328 * are 1, 6, and 11. We'll get a result faster if we check
1329 * every 5 channels, but in order to hit all of them the
1330 * number of channels must be relatively prime to 5. If it's
1331 * not, tweak the hop.
1332 */
1333 ctx->hop_step = 5;
1334 while ( dev->nr_channels % ctx->hop_step == 0 && ctx->hop_step > 1 )
1335 ctx->hop_step--;
1336
1337 ctx->beacons = malloc ( sizeof ( *ctx->beacons ) );
1338 INIT_LIST_HEAD ( ctx->beacons );
1339
1340 dev->channel = 0;
1341 dev->op->config ( dev, NET80211_CFG_CHANNEL );
1342
1343 return ctx;
1344 }
1345
1346 /**
1347 * Continue probe of 802.11 networks
1348 *
1349 * @v ctx Probe context returned by net80211_probe_start()
1350 * @ret rc Probe status
1351 *
1352 * The return code will be 0 if the probe is still going on (and this
1353 * function should be called again), a positive number if the probe
1354 * completed successfully, or a negative error code if the probe
1355 * failed for that reason.
1356 *
1357 * Whether the probe succeeded or failed, you must call
1358 * net80211_probe_finish_all() or net80211_probe_finish_best()
1359 * (depending on whether you want information on all networks or just
1360 * the best-signal one) in order to release the probe context. A
1361 * failed probe may still have acquired some valid data.
1362 */
1363 int net80211_probe_step ( struct net80211_probe_ctx *ctx )
1364 {
1365 struct net80211_device *dev = ctx->dev;
1366 u32 start_timeout = NET80211_PROBE_TIMEOUT * ticks_per_sec();
1367 u32 gather_timeout = ticks_per_sec();
1368 u32 now = currticks();
1369 struct io_buffer *iob;
1370 int signal;
1371 int rc;
1372 char ssid[IEEE80211_MAX_SSID_LEN + 1];
1373
1374 gather_timeout *= ( ctx->essid[0] ? NET80211_PROBE_GATHER :
1375 NET80211_PROBE_GATHER_ALL );
1376
1377 /* Time out if necessary */
1378 if ( now >= ctx->ticks_start + start_timeout )
1379 return list_empty ( ctx->beacons ) ? -ETIMEDOUT : +1;
1380
1381 if ( ctx->ticks_beacon > 0 && now >= ctx->ticks_start + gather_timeout )
1382 return +1;
1383
1384 /* Change channels if necessary */
1385 if ( now >= ctx->ticks_channel + ctx->hop_time ) {
1386 dev->channel = ( dev->channel + ctx->hop_step )
1387 % dev->nr_channels;
1388 dev->op->config ( dev, NET80211_CFG_CHANNEL );
1389 udelay ( dev->hw->channel_change_time );
1390
1391 ctx->ticks_channel = now;
1392
1393 if ( ctx->probe ) {
1394 struct io_buffer *siob = ctx->probe; /* to send */
1395
1396 /* make a copy for future use */
1397 iob = alloc_iob ( siob->tail - siob->head );
1398 iob_reserve ( iob, iob_headroom ( siob ) );
1399 memcpy ( iob_put ( iob, iob_len ( siob ) ),
1400 siob->data, iob_len ( siob ) );
1401
1402 ctx->probe = iob;
1403 rc = net80211_tx_mgmt ( dev, IEEE80211_STYPE_PROBE_REQ,
1404 eth_broadcast,
1405 iob_disown ( siob ) );
1406 if ( rc ) {
1407 DBGC ( dev, "802.11 %p send probe failed: "
1408 "%s\n", dev, strerror ( rc ) );
1409 return rc;
1410 }
1411 }
1412 }
1413
1414 /* Check for new management packets */
1415 while ( ( iob = net80211_mgmt_dequeue ( dev, &signal ) ) != NULL ) {
1416 struct ieee80211_frame *hdr;
1417 struct ieee80211_beacon *beacon;
1418 union ieee80211_ie *ie;
1419 struct net80211_wlan *wlan;
1420 u16 type;
1421
1422 hdr = iob->data;
1423 type = hdr->fc & IEEE80211_FC_SUBTYPE;
1424 beacon = ( struct ieee80211_beacon * ) hdr->data;
1425
1426 if ( type != IEEE80211_STYPE_BEACON &&
1427 type != IEEE80211_STYPE_PROBE_RESP ) {
1428 DBGC2 ( dev, "802.11 %p probe: non-beacon\n", dev );
1429 goto drop;
1430 }
1431
1432 if ( ( void * ) beacon->info_element >= iob->tail ) {
1433 DBGC ( dev, "802.11 %p probe: beacon with no IEs\n",
1434 dev );
1435 goto drop;
1436 }
1437
1438 ie = beacon->info_element;
1439
1440 if ( ! ieee80211_ie_bound ( ie, iob->tail ) )
1441 ie = NULL;
1442
1443 while ( ie && ie->id != IEEE80211_IE_SSID )
1444 ie = ieee80211_next_ie ( ie, iob->tail );
1445
1446 if ( ! ie ) {
1447 DBGC ( dev, "802.11 %p probe: beacon with no SSID\n",
1448 dev );
1449 goto drop;
1450 }
1451
1452 memcpy ( ssid, ie->ssid, ie->len );
1453 ssid[ie->len] = 0;
1454
1455 if ( ctx->essid[0] && strcmp ( ctx->essid, ssid ) != 0 ) {
1456 DBGC2 ( dev, "802.11 %p probe: beacon with wrong SSID "
1457 "(%s)\n", dev, ssid );
1458 goto drop;
1459 }
1460
1461 /* See if we've got an entry for this network */
1462 list_for_each_entry ( wlan, ctx->beacons, list ) {
1463 if ( strcmp ( wlan->essid, ssid ) != 0 )
1464 continue;
1465
1466 if ( signal < wlan->signal ) {
1467 DBGC2 ( dev, "802.11 %p probe: beacon for %s "
1468 "(%s) with weaker signal %d\n", dev,
1469 ssid, eth_ntoa ( hdr->addr3 ), signal );
1470 goto drop;
1471 }
1472
1473 goto fill;
1474 }
1475
1476 /* No entry yet - make one */
1477 wlan = zalloc ( sizeof ( *wlan ) );
1478 strcpy ( wlan->essid, ssid );
1479 list_add_tail ( &wlan->list, ctx->beacons );
1480
1481 /* Whether we're using an old entry or a new one, fill
1482 it with new data. */
1483 fill:
1484 memcpy ( wlan->bssid, hdr->addr3, ETH_ALEN );
1485 wlan->signal = signal;
1486 wlan->channel = dev->channels[dev->channel].channel_nr;
1487
1488 /* Copy this I/O buffer into a new wlan->beacon; the
1489 * iob we've got probably came from the device driver
1490 * and may have the full 2.4k allocation, which we
1491 * don't want to keep around wasting memory.
1492 */
1493 free_iob ( wlan->beacon );
1494 wlan->beacon = alloc_iob ( iob_len ( iob ) );
1495 memcpy ( iob_put ( wlan->beacon, iob_len ( iob ) ),
1496 iob->data, iob_len ( iob ) );
1497
1498 if ( ( rc = sec80211_detect ( wlan->beacon, &wlan->handshaking,
1499 &wlan->crypto ) ) == -ENOTSUP ) {
1500 struct ieee80211_beacon *beacon =
1501 ( struct ieee80211_beacon * ) hdr->data;
1502
1503 if ( beacon->capability & IEEE80211_CAPAB_PRIVACY ) {
1504 DBG ( "802.11 %p probe: secured network %s but "
1505 "encryption support not compiled in\n",
1506 dev, wlan->essid );
1507 wlan->handshaking = NET80211_SECPROT_UNKNOWN;
1508 wlan->crypto = NET80211_CRYPT_UNKNOWN;
1509 } else {
1510 wlan->handshaking = NET80211_SECPROT_NONE;
1511 wlan->crypto = NET80211_CRYPT_NONE;
1512 }
1513 } else if ( rc != 0 ) {
1514 DBGC ( dev, "802.11 %p probe warning: network "
1515 "%s with unidentifiable security "
1516 "settings: %s\n", dev, wlan->essid,
1517 strerror ( rc ) );
1518 }
1519
1520 ctx->ticks_beacon = now;
1521
1522 DBGC2 ( dev, "802.11 %p probe: good beacon for %s (%s)\n",
1523 dev, wlan->essid, eth_ntoa ( wlan->bssid ) );
1524
1525 drop:
1526 free_iob ( iob );
1527 }
1528
1529 return 0;
1530 }
1531
1532
1533 /**
1534 * Finish probe of 802.11 networks, returning best-signal network found
1535 *
1536 * @v ctx Probe context
1537 * @ret wlan Best-signal network found, or @c NULL if none were found
1538 *
1539 * If net80211_probe_start() was called with a particular SSID
1540 * parameter as filter, only a network with that SSID (matching
1541 * case-sensitively) can be returned from this function.
1542 */
1543 struct net80211_wlan *
1544 net80211_probe_finish_best ( struct net80211_probe_ctx *ctx )
1545 {
1546 struct net80211_wlan *best = NULL, *wlan;
1547
1548 if ( ! ctx )
1549 return NULL;
1550
1551 list_for_each_entry ( wlan, ctx->beacons, list ) {
1552 if ( ! best || best->signal < wlan->signal )
1553 best = wlan;
1554 }
1555
1556 if ( best )
1557 list_del ( &best->list );
1558 else
1559 DBGC ( ctx->dev, "802.11 %p probe: found nothing for '%s'\n",
1560 ctx->dev, ctx->essid );
1561
1562 net80211_free_wlanlist ( ctx->beacons );
1563
1564 net80211_keep_mgmt ( ctx->dev, ctx->old_keep_mgmt );
1565
1566 if ( ctx->probe )
1567 free_iob ( ctx->probe );
1568
1569 free ( ctx );
1570
1571 return best;
1572 }
1573
1574
1575 /**
1576 * Finish probe of 802.11 networks, returning all networks found
1577 *
1578 * @v ctx Probe context
1579 * @ret list List of net80211_wlan detailing networks found
1580 *
1581 * If net80211_probe_start() was called with a particular SSID
1582 * parameter as filter, this will always return either an empty or a
1583 * one-element list.
1584 */
1585 struct list_head *net80211_probe_finish_all ( struct net80211_probe_ctx *ctx )
1586 {
1587 struct list_head *beacons = ctx->beacons;
1588
1589 if ( ! ctx )
1590 return NULL;
1591
1592 net80211_keep_mgmt ( ctx->dev, ctx->old_keep_mgmt );
1593
1594 if ( ctx->probe )
1595 free_iob ( ctx->probe );
1596
1597 free ( ctx );
1598
1599 return beacons;
1600 }
1601
1602
1603 /**
1604 * Free WLAN structure
1605 *
1606 * @v wlan WLAN structure to free
1607 */
1608 void net80211_free_wlan ( struct net80211_wlan *wlan )
1609 {
1610 if ( wlan ) {
1611 free_iob ( wlan->beacon );
1612 free ( wlan );
1613 }
1614 }
1615
1616
1617 /**
1618 * Free list of WLAN structures
1619 *
1620 * @v list List of WLAN structures to free
1621 */
1622 void net80211_free_wlanlist ( struct list_head *list )
1623 {
1624 struct net80211_wlan *wlan, *tmp;
1625
1626 if ( ! list )
1627 return;
1628
1629 list_for_each_entry_safe ( wlan, tmp, list, list ) {
1630 list_del ( &wlan->list );
1631 net80211_free_wlan ( wlan );
1632 }
1633
1634 free ( list );
1635 }
1636
1637
1638 /** Number of ticks to wait for replies to association management frames */
1639 #define ASSOC_TIMEOUT TICKS_PER_SEC
1640
1641 /** Number of times to try sending a particular association management frame */
1642 #define ASSOC_RETRIES 2
1643
1644 /**
1645 * Step 802.11 association process
1646 *
1647 * @v dev 802.11 device
1648 */
1649 static void net80211_step_associate ( struct net80211_device *dev )
1650 {
1651 int rc = 0;
1652 int status = dev->state & NET80211_STATUS_MASK;
1653
1654 /*
1655 * We use a sort of state machine implemented using bits in
1656 * the dev->state variable. At each call, we take the
1657 * logically first step that has not yet succeeded; either it
1658 * has not been tried yet, it's being retried, or it failed.
1659 * If it failed, we return an error indication; otherwise we
1660 * perform the step. If it succeeds, RX handling code will set
1661 * the appropriate status bit for us.
1662 *
1663 * Probe works a bit differently, since we have to step it
1664 * on every call instead of waiting for a packet to arrive
1665 * that will set the completion bit for us.
1666 */
1667
1668 /* If we're waiting for a reply, check for timeout condition */
1669 if ( dev->state & NET80211_WAITING ) {
1670 /* Sanity check */
1671 if ( ! dev->associating )
1672 return;
1673
1674 if ( currticks() - dev->ctx.assoc->last_packet > ASSOC_TIMEOUT ) {
1675 /* Timed out - fail if too many retries, or retry */
1676 dev->ctx.assoc->times_tried++;
1677 if ( ++dev->ctx.assoc->times_tried > ASSOC_RETRIES ) {
1678 rc = -ETIMEDOUT;
1679 goto fail;
1680 }
1681 } else {
1682 /* Didn't time out - let it keep going */
1683 return;
1684 }
1685 } else {
1686 if ( dev->state & NET80211_PROBED )
1687 dev->ctx.assoc->times_tried = 0;
1688 }
1689
1690 if ( ! ( dev->state & NET80211_PROBED ) ) {
1691 /* state: probe */
1692
1693 if ( ! dev->ctx.probe ) {
1694 /* start probe */
1695 int active = fetch_intz_setting ( NULL,
1696 &net80211_active_setting );
1697 int band = dev->hw->bands;
1698
1699 if ( active )
1700 band &= ~NET80211_BAND_BIT_5GHZ;
1701
1702 rc = net80211_prepare_probe ( dev, band, active );
1703 if ( rc )
1704 goto fail;
1705
1706 dev->ctx.probe = net80211_probe_start ( dev, dev->essid,
1707 active );
1708 if ( ! dev->ctx.probe ) {
1709 dev->assoc_rc = -ENOMEM;
1710 goto fail;
1711 }
1712 }
1713
1714 rc = net80211_probe_step ( dev->ctx.probe );
1715 if ( ! rc ) {
1716 return; /* still going */
1717 }
1718
1719 dev->associating = net80211_probe_finish_best ( dev->ctx.probe );
1720 dev->ctx.probe = NULL;
1721 if ( ! dev->associating ) {
1722 if ( rc > 0 ) /* "successful" probe found nothing */
1723 rc = -ETIMEDOUT;
1724 goto fail;
1725 }
1726
1727 /* If we probed using a broadcast SSID, record that
1728 fact for the settings applicator before we clobber
1729 it with the specific SSID we've chosen. */
1730 if ( ! dev->essid[0] )
1731 dev->state |= NET80211_AUTO_SSID;
1732
1733 DBGC ( dev, "802.11 %p found network %s (%s)\n", dev,
1734 dev->associating->essid,
1735 eth_ntoa ( dev->associating->bssid ) );
1736
1737 dev->ctx.assoc = zalloc ( sizeof ( *dev->ctx.assoc ) );
1738 if ( ! dev->ctx.assoc ) {
1739 rc = -ENOMEM;
1740 goto fail;
1741 }
1742
1743 dev->state |= NET80211_PROBED;
1744 dev->ctx.assoc->method = IEEE80211_AUTH_OPEN_SYSTEM;
1745
1746 return;
1747 }
1748
1749 /* Record time of sending the packet we're about to send, for timeout */
1750 dev->ctx.assoc->last_packet = currticks();
1751
1752 if ( ! ( dev->state & NET80211_AUTHENTICATED ) ) {
1753 /* state: prepare and authenticate */
1754
1755 if ( status != IEEE80211_STATUS_SUCCESS ) {
1756 /* we tried authenticating already, but failed */
1757 int method = dev->ctx.assoc->method;
1758
1759 if ( method == IEEE80211_AUTH_OPEN_SYSTEM &&
1760 ( status == IEEE80211_STATUS_AUTH_CHALL_INVALID ||
1761 status == IEEE80211_STATUS_AUTH_ALGO_UNSUPP ) ) {
1762 /* Maybe this network uses Shared Key? */
1763 dev->ctx.assoc->method =
1764 IEEE80211_AUTH_SHARED_KEY;
1765 } else {
1766 goto fail;
1767 }
1768 }
1769
1770 DBGC ( dev, "802.11 %p authenticating with method %d\n", dev,
1771 dev->ctx.assoc->method );
1772
1773 rc = net80211_prepare_assoc ( dev, dev->associating );
1774 if ( rc )
1775 goto fail;
1776
1777 rc = net80211_send_auth ( dev, dev->associating,
1778 dev->ctx.assoc->method );
1779 if ( rc )
1780 goto fail;
1781
1782 return;
1783 }
1784
1785 if ( ! ( dev->state & NET80211_ASSOCIATED ) ) {
1786 /* state: associate */
1787
1788 if ( status != IEEE80211_STATUS_SUCCESS )
1789 goto fail;
1790
1791 DBGC ( dev, "802.11 %p associating\n", dev );
1792
1793 if ( dev->handshaker && dev->handshaker->start &&
1794 ! dev->handshaker->started ) {
1795 rc = dev->handshaker->start ( dev );
1796 if ( rc < 0 )
1797 goto fail;
1798 dev->handshaker->started = 1;
1799 }
1800
1801 rc = net80211_send_assoc ( dev, dev->associating );
1802 if ( rc )
1803 goto fail;
1804
1805 return;
1806 }
1807
1808 if ( ! ( dev->state & NET80211_CRYPTO_SYNCED ) ) {
1809 /* state: crypto sync */
1810 DBGC ( dev, "802.11 %p security handshaking\n", dev );
1811
1812 if ( ! dev->handshaker || ! dev->handshaker->step ) {
1813 dev->state |= NET80211_CRYPTO_SYNCED;
1814 return;
1815 }
1816
1817 rc = dev->handshaker->step ( dev );
1818
1819 if ( rc < 0 ) {
1820 /* Only record the returned error if we're
1821 still marked as associated, because an
1822 asynchronous error will have already been
1823 reported to net80211_deauthenticate() and
1824 assoc_rc thereby set. */
1825 if ( dev->state & NET80211_ASSOCIATED )
1826 dev->assoc_rc = rc;
1827 rc = 0;
1828 goto fail;
1829 }
1830
1831 if ( rc > 0 ) {
1832 dev->assoc_rc = 0;
1833 dev->state |= NET80211_CRYPTO_SYNCED;
1834 }
1835 return;
1836 }
1837
1838 /* state: done! */
1839 netdev_link_up ( dev->netdev );
1840 dev->assoc_rc = 0;
1841 dev->state &= ~NET80211_WORKING;
1842
1843 free ( dev->ctx.assoc );
1844 dev->ctx.assoc = NULL;
1845
1846 net80211_free_wlan ( dev->associating );
1847 dev->associating = NULL;
1848
1849 dev->rctl = rc80211_init ( dev );
1850
1851 process_del ( &dev->proc_assoc );
1852
1853 DBGC ( dev, "802.11 %p associated with %s (%s)\n", dev,
1854 dev->essid, eth_ntoa ( dev->bssid ) );
1855
1856 return;
1857
1858 fail:
1859 dev->state &= ~( NET80211_WORKING | NET80211_WAITING );
1860 if ( rc )
1861 dev->assoc_rc = rc;
1862
1863 netdev_link_err ( dev->netdev, dev->assoc_rc );
1864
1865 /* We never reach here from the middle of a probe, so we don't
1866 need to worry about freeing dev->ctx.probe. */
1867
1868 if ( dev->state & NET80211_PROBED ) {
1869 free ( dev->ctx.assoc );
1870 dev->ctx.assoc = NULL;
1871 }
1872
1873 net80211_free_wlan ( dev->associating );
1874 dev->associating = NULL;
1875
1876 process_del ( &dev->proc_assoc );
1877
1878 DBGC ( dev, "802.11 %p association failed (state=%04x): "
1879 "%s\n", dev, dev->state, strerror ( dev->assoc_rc ) );
1880
1881 /* Try it again: */
1882 net80211_autoassociate ( dev );
1883 }
1884
1885 /**
1886 * Check for 802.11 SSID or key updates
1887 *
1888 * This acts as a settings applicator; if the user changes netX/ssid,
1889 * and netX is currently open, the association task will be invoked
1890 * again. If the user changes the encryption key, the current security
1891 * handshaker will be asked to update its state to match; if that is
1892 * impossible without reassociation, we reassociate.
1893 */
1894 static int net80211_check_settings_update ( void )
1895 {
1896 struct net80211_device *dev;
1897 char ssid[IEEE80211_MAX_SSID_LEN + 1];
1898 int key_reassoc;
1899
1900 list_for_each_entry ( dev, &net80211_devices, list ) {
1901 if ( ! netdev_is_open ( dev->netdev ) )
1902 continue;
1903
1904 key_reassoc = 0;
1905 if ( dev->handshaker && dev->handshaker->change_key &&
1906 dev->handshaker->change_key ( dev ) < 0 )
1907 key_reassoc = 1;
1908
1909 fetch_string_setting ( netdev_settings ( dev->netdev ),
1910 &net80211_ssid_setting, ssid,
1911 IEEE80211_MAX_SSID_LEN + 1 );
1912
1913 if ( key_reassoc ||
1914 ( ! ( ! ssid[0] && ( dev->state & NET80211_AUTO_SSID ) ) &&
1915 strcmp ( ssid, dev->essid ) != 0 ) ) {
1916 DBGC ( dev, "802.11 %p updating association: "
1917 "%s -> %s\n", dev, dev->essid, ssid );
1918 net80211_autoassociate ( dev );
1919 }
1920 }
1921
1922 return 0;
1923 }
1924
1925 /**
1926 * Start 802.11 association process
1927 *
1928 * @v dev 802.11 device
1929 *
1930 * If the association process is running, it will be restarted.
1931 */
1932 void net80211_autoassociate ( struct net80211_device *dev )
1933 {
1934 if ( ! ( dev->state & NET80211_WORKING ) ) {
1935 DBGC2 ( dev, "802.11 %p spawning association process\n", dev );
1936 process_add ( &dev->proc_assoc );
1937 } else {
1938 DBGC2 ( dev, "802.11 %p restarting association\n", dev );
1939 }
1940
1941 /* Clean up everything an earlier association process might
1942 have been in the middle of using */
1943 if ( dev->associating )
1944 net80211_free_wlan ( dev->associating );
1945
1946 if ( ! ( dev->state & NET80211_PROBED ) )
1947 net80211_free_wlan (
1948 net80211_probe_finish_best ( dev->ctx.probe ) );
1949 else
1950 free ( dev->ctx.assoc );
1951
1952 /* Reset to a clean state */
1953 fetch_string_setting ( netdev_settings ( dev->netdev ),
1954 &net80211_ssid_setting, dev->essid,
1955 IEEE80211_MAX_SSID_LEN + 1 );
1956 dev->ctx.probe = NULL;
1957 dev->associating = NULL;
1958 dev->assoc_rc = 0;
1959 net80211_set_state ( dev, NET80211_PROBED, NET80211_WORKING, 0 );
1960 }
1961
1962 /**
1963 * Pick TX rate for RTS/CTS packets based on data rate
1964 *
1965 * @v dev 802.11 device
1966 *
1967 * The RTS/CTS rate is the fastest TX rate marked as "basic" that is
1968 * not faster than the data rate.
1969 */
1970 static void net80211_set_rtscts_rate ( struct net80211_device *dev )
1971 {
1972 u16 datarate = dev->rates[dev->rate];
1973 u16 rtsrate = 0;
1974 int rts_idx = -1;
1975 int i;
1976
1977 for ( i = 0; i < dev->nr_rates; i++ ) {
1978 u16 rate = dev->rates[i];
1979
1980 if ( ! ( dev->basic_rates & ( 1 << i ) ) || rate > datarate )
1981 continue;
1982
1983 if ( rate > rtsrate ) {
1984 rtsrate = rate;
1985 rts_idx = i;
1986 }
1987 }
1988
1989 /* If this is in initialization, we might not have any basic
1990 rates; just use the first data rate in that case. */
1991 if ( rts_idx < 0 )
1992 rts_idx = 0;
1993
1994 dev->rtscts_rate = rts_idx;
1995 }
1996
1997 /**
1998 * Set data transmission rate for 802.11 device
1999 *
2000 * @v dev 802.11 device
2001 * @v rate Rate to set, as index into @c dev->rates array
2002 */
2003 void net80211_set_rate_idx ( struct net80211_device *dev, int rate )
2004 {
2005 assert ( netdev_is_open ( dev->netdev ) );
2006
2007 if ( rate >= 0 && rate < dev->nr_rates && rate != dev->rate ) {
2008 DBGC2 ( dev, "802.11 %p changing rate from %d->%d Mbps\n",
2009 dev, dev->rates[dev->rate] / 10,
2010 dev->rates[rate] / 10 );
2011
2012 dev->rate = rate;
2013 net80211_set_rtscts_rate ( dev );
2014 dev->op->config ( dev, NET80211_CFG_RATE );
2015 }
2016 }
2017
2018 /**
2019 * Configure 802.11 device to transmit on a certain channel
2020 *
2021 * @v dev 802.11 device
2022 * @v channel Channel number (1-11 for 2.4GHz) to transmit on
2023 */
2024 int net80211_change_channel ( struct net80211_device *dev, int channel )
2025 {
2026 int i, oldchan = dev->channel;
2027
2028 assert ( netdev_is_open ( dev->netdev ) );
2029
2030 for ( i = 0; i < dev->nr_channels; i++ ) {
2031 if ( dev->channels[i].channel_nr == channel ) {
2032 dev->channel = i;
2033 break;
2034 }
2035 }
2036
2037 if ( i == dev->nr_channels )
2038 return -ENOENT;
2039
2040 if ( i != oldchan )
2041 return dev->op->config ( dev, NET80211_CFG_CHANNEL );
2042
2043 return 0;
2044 }
2045
2046 /**
2047 * Prepare 802.11 device channel and rate set for scanning
2048 *
2049 * @v dev 802.11 device
2050 * @v band RF band(s) on which to prepare for scanning
2051 * @v active Whether the scanning will be active
2052 * @ret rc Return status code
2053 */
2054 int net80211_prepare_probe ( struct net80211_device *dev, int band,
2055 int active )
2056 {
2057 assert ( netdev_is_open ( dev->netdev ) );
2058
2059 if ( active && ( band & NET80211_BAND_BIT_5GHZ ) ) {
2060 DBGC ( dev, "802.11 %p cannot perform active scanning on "
2061 "5GHz band\n", dev );
2062 return -EINVAL_ACTIVE_SCAN;
2063 }
2064
2065 if ( band == 0 ) {
2066 /* This can happen for a 5GHz-only card with 5GHz
2067 scanning masked out by an active request. */
2068 DBGC ( dev, "802.11 %p asked to prepare for scanning nothing\n",
2069 dev );
2070 return -EINVAL_ACTIVE_SCAN;
2071 }
2072
2073 dev->nr_channels = 0;
2074
2075 if ( active )
2076 net80211_add_channels ( dev, 1, 11, NET80211_REG_TXPOWER );
2077 else {
2078 if ( band & NET80211_BAND_BIT_2GHZ )
2079 net80211_add_channels ( dev, 1, 14,
2080 NET80211_REG_TXPOWER );
2081 if ( band & NET80211_BAND_BIT_5GHZ )
2082 net80211_add_channels ( dev, 36, 8,
2083 NET80211_REG_TXPOWER );
2084 }
2085
2086 net80211_filter_hw_channels ( dev );
2087
2088 /* Use channel 1 for now */
2089 dev->channel = 0;
2090 dev->op->config ( dev, NET80211_CFG_CHANNEL );
2091
2092 /* Always do active probes at lowest (presumably first) speed */
2093 dev->rate = 0;
2094 dev->nr_rates = 1;
2095 dev->rates[0] = dev->hw->rates[dev->channels[0].band][0];
2096 dev->op->config ( dev, NET80211_CFG_RATE );
2097
2098 return 0;
2099 }
2100
2101 /**
2102 * Prepare 802.11 device channel and rate set for communication
2103 *
2104 * @v dev 802.11 device
2105 * @v wlan WLAN to prepare for communication with
2106 * @ret rc Return status code
2107 */
2108 int net80211_prepare_assoc ( struct net80211_device *dev,
2109 struct net80211_wlan *wlan )
2110 {
2111 struct ieee80211_frame *hdr = wlan->beacon->data;
2112 struct ieee80211_beacon *beacon =
2113 ( struct ieee80211_beacon * ) hdr->data;
2114 struct net80211_handshaker *handshaker;
2115 int rc;
2116
2117 assert ( netdev_is_open ( dev->netdev ) );
2118
2119 net80211_set_state ( dev, NET80211_ASSOCIATED, 0, 0 );
2120 memcpy ( dev->bssid, wlan->bssid, ETH_ALEN );
2121 strcpy ( dev->essid, wlan->essid );
2122
2123 free ( dev->rsn_ie );
2124 dev->rsn_ie = NULL;
2125
2126 dev->last_beacon_timestamp = beacon->timestamp;
2127 dev->tx_beacon_interval = 1024 * beacon->beacon_interval;
2128
2129 /* Barring an IE that tells us the channel outright, assume
2130 the channel we heard this AP best on is the channel it's
2131 communicating on. */
2132 net80211_change_channel ( dev, wlan->channel );
2133
2134 rc = net80211_process_capab ( dev, beacon->capability );
2135 if ( rc )
2136 return rc;
2137
2138 rc = net80211_process_ie ( dev, beacon->info_element,
2139 wlan->beacon->tail );
2140 if ( rc )
2141 return rc;
2142
2143 /* Associate at the lowest rate so we know it'll get through */
2144 dev->rate = 0;
2145 dev->op->config ( dev, NET80211_CFG_RATE );
2146
2147 /* Free old handshaker and crypto, if they exist */
2148 if ( dev->handshaker && dev->handshaker->stop &&
2149 dev->handshaker->started )
2150 dev->handshaker->stop ( dev );
2151 free ( dev->handshaker );
2152 dev->handshaker = NULL;
2153 free ( dev->crypto );
2154 free ( dev->gcrypto );
2155 dev->crypto = dev->gcrypto = NULL;
2156
2157 /* Find new security handshaker to use */
2158 for_each_table_entry ( handshaker, NET80211_HANDSHAKERS ) {
2159 if ( handshaker->protocol == wlan->handshaking ) {
2160 dev->handshaker = zalloc ( sizeof ( *handshaker ) +
2161 handshaker->priv_len );
2162 if ( ! dev->handshaker )
2163 return -ENOMEM;
2164
2165 memcpy ( dev->handshaker, handshaker,
2166 sizeof ( *handshaker ) );
2167 dev->handshaker->priv = ( ( void * ) dev->handshaker +
2168 sizeof ( *handshaker ) );
2169 break;
2170 }
2171 }
2172
2173 if ( ( wlan->handshaking != NET80211_SECPROT_NONE ) &&
2174 ! dev->handshaker ) {
2175 DBGC ( dev, "802.11 %p no support for handshaking scheme %d\n",
2176 dev, wlan->handshaking );
2177 return -( ENOTSUP | ( wlan->handshaking << 8 ) );
2178 }
2179
2180 /* Initialize security handshaker */
2181 if ( dev->handshaker ) {
2182 rc = dev->handshaker->init ( dev );
2183 if ( rc < 0 )
2184 return rc;
2185 }
2186
2187 return 0;
2188 }
2189
2190 /**
2191 * Send 802.11 initial authentication frame
2192 *
2193 * @v dev 802.11 device
2194 * @v wlan WLAN to authenticate with
2195 * @v method Authentication method
2196 * @ret rc Return status code
2197 *
2198 * @a method may be 0 for Open System authentication or 1 for Shared
2199 * Key authentication. Open System provides no security in association
2200 * whatsoever, relying on encryption for confidentiality, but Shared
2201 * Key actively introduces security problems and is very rarely used.
2202 */
2203 int net80211_send_auth ( struct net80211_device *dev,
2204 struct net80211_wlan *wlan, int method )
2205 {
2206 struct io_buffer *iob = alloc_iob ( 64 );
2207 struct ieee80211_auth *auth;
2208
2209 net80211_set_state ( dev, 0, NET80211_WAITING, 0 );
2210 iob_reserve ( iob, IEEE80211_TYP_FRAME_HEADER_LEN );
2211 auth = iob_put ( iob, sizeof ( *auth ) );
2212 auth->algorithm = method;
2213 auth->tx_seq = 1;
2214 auth->status = 0;
2215
2216 return net80211_tx_mgmt ( dev, IEEE80211_STYPE_AUTH, wlan->bssid, iob );
2217 }
2218
2219 /**
2220 * Handle receipt of 802.11 authentication frame
2221 *
2222 * @v dev 802.11 device
2223 * @v iob I/O buffer
2224 *
2225 * If the authentication method being used is Shared Key, and the
2226 * frame that was received included challenge text, the frame is
2227 * encrypted using the cryptosystem currently in effect and sent back
2228 * to the AP to complete the authentication.
2229 */
2230 static void net80211_handle_auth ( struct net80211_device *dev,
2231 struct io_buffer *iob )
2232 {
2233 struct ieee80211_frame *hdr = iob->data;
2234 struct ieee80211_auth *auth =
2235 ( struct ieee80211_auth * ) hdr->data;
2236
2237 if ( auth->tx_seq & 1 ) {
2238 DBGC ( dev, "802.11 %p authentication received improperly "
2239 "directed frame (seq. %d)\n", dev, auth->tx_seq );
2240 net80211_set_state ( dev, NET80211_WAITING, 0,
2241 IEEE80211_STATUS_FAILURE );
2242 return;
2243 }
2244
2245 if ( auth->status != IEEE80211_STATUS_SUCCESS ) {
2246 DBGC ( dev, "802.11 %p authentication failed: status %d\n",
2247 dev, auth->status );
2248 net80211_set_state ( dev, NET80211_WAITING, 0,
2249 auth->status );
2250 return;
2251 }
2252
2253 if ( auth->algorithm == IEEE80211_AUTH_SHARED_KEY && ! dev->crypto ) {
2254 DBGC ( dev, "802.11 %p can't perform shared-key authentication "
2255 "without a cryptosystem\n", dev );
2256 net80211_set_state ( dev, NET80211_WAITING, 0,
2257 IEEE80211_STATUS_FAILURE );
2258 return;
2259 }
2260
2261 if ( auth->algorithm == IEEE80211_AUTH_SHARED_KEY &&
2262 auth->tx_seq == 2 ) {
2263 /* Since the iob we got is going to be freed as soon
2264 as we return, we can do some in-place
2265 modification. */
2266 auth->tx_seq = 3;
2267 auth->status = 0;
2268
2269 memcpy ( hdr->addr2, hdr->addr1, ETH_ALEN );
2270 memcpy ( hdr->addr1, hdr->addr3, ETH_ALEN );
2271
2272 netdev_tx ( dev->netdev,
2273 dev->crypto->encrypt ( dev->crypto, iob ) );
2274 return;
2275 }
2276
2277 net80211_set_state ( dev, NET80211_WAITING, NET80211_AUTHENTICATED,
2278 IEEE80211_STATUS_SUCCESS );
2279
2280 return;
2281 }
2282
2283 /**
2284 * Send 802.11 association frame
2285 *
2286 * @v dev 802.11 device
2287 * @v wlan WLAN to associate with
2288 * @ret rc Return status code
2289 */
2290 int net80211_send_assoc ( struct net80211_device *dev,
2291 struct net80211_wlan *wlan )
2292 {
2293 struct io_buffer *iob = alloc_iob ( 128 );
2294 struct ieee80211_assoc_req *assoc;
2295 union ieee80211_ie *ie;
2296
2297 net80211_set_state ( dev, 0, NET80211_WAITING, 0 );
2298
2299 iob_reserve ( iob, IEEE80211_TYP_FRAME_HEADER_LEN );
2300 assoc = iob->data;
2301
2302 assoc->capability = IEEE80211_CAPAB_MANAGED;
2303 if ( ! ( dev->hw->flags & NET80211_HW_NO_SHORT_PREAMBLE ) )
2304 assoc->capability |= IEEE80211_CAPAB_SHORT_PMBL;
2305 if ( ! ( dev->hw->flags & NET80211_HW_NO_SHORT_SLOT ) )
2306 assoc->capability |= IEEE80211_CAPAB_SHORT_SLOT;
2307 if ( wlan->crypto )
2308 assoc->capability |= IEEE80211_CAPAB_PRIVACY;
2309
2310 assoc->listen_interval = 1;
2311
2312 ie = net80211_marshal_request_info ( dev, assoc->info_element );
2313
2314 DBGP ( "802.11 %p about to send association request:\n", dev );
2315 DBGP_HD ( iob->data, ( void * ) ie - iob->data );
2316
2317 iob_put ( iob, ( void * ) ie - iob->data );
2318
2319 return net80211_tx_mgmt ( dev, IEEE80211_STYPE_ASSOC_REQ,
2320 wlan->bssid, iob );
2321 }
2322
2323 /**
2324 * Handle receipt of 802.11 association reply frame
2325 *
2326 * @v dev 802.11 device
2327 * @v iob I/O buffer
2328 */
2329 static void net80211_handle_assoc_reply ( struct net80211_device *dev,
2330 struct io_buffer *iob )
2331 {
2332 struct ieee80211_frame *hdr = iob->data;
2333 struct ieee80211_assoc_resp *assoc =
2334 ( struct ieee80211_assoc_resp * ) hdr->data;
2335
2336 net80211_process_capab ( dev, assoc->capability );
2337 net80211_process_ie ( dev, assoc->info_element, iob->tail );
2338
2339 if ( assoc->status != IEEE80211_STATUS_SUCCESS ) {
2340 DBGC ( dev, "802.11 %p association failed: status %d\n",
2341 dev, assoc->status );
2342 net80211_set_state ( dev, NET80211_WAITING, 0,
2343 assoc->status );
2344 return;
2345 }
2346
2347 /* ESSID was filled before the association request was sent */
2348 memcpy ( dev->bssid, hdr->addr3, ETH_ALEN );
2349 dev->aid = assoc->aid;
2350
2351 net80211_set_state ( dev, NET80211_WAITING, NET80211_ASSOCIATED,
2352 IEEE80211_STATUS_SUCCESS );
2353 }
2354
2355
2356 /**
2357 * Send 802.11 disassociation frame
2358 *
2359 * @v dev 802.11 device
2360 * @v reason Reason for disassociation
2361 * @v deauth If TRUE, send deauthentication instead of disassociation
2362 * @ret rc Return status code
2363 */
2364 static int net80211_send_disassoc ( struct net80211_device *dev, int reason,
2365 int deauth )
2366 {
2367 struct io_buffer *iob = alloc_iob ( 64 );
2368 struct ieee80211_disassoc *disassoc;
2369
2370 if ( ! ( dev->state & NET80211_ASSOCIATED ) )
2371 return -EINVAL;
2372
2373 net80211_set_state ( dev, NET80211_ASSOCIATED, 0, 0 );
2374 iob_reserve ( iob, IEEE80211_TYP_FRAME_HEADER_LEN );
2375 disassoc = iob_put ( iob, sizeof ( *disassoc ) );
2376 disassoc->reason = reason;
2377
2378 return net80211_tx_mgmt ( dev, deauth ? IEEE80211_STYPE_DEAUTH :
2379 IEEE80211_STYPE_DISASSOC, dev->bssid, iob );
2380 }
2381
2382
2383 /**
2384 * Deauthenticate from current network and try again
2385 *
2386 * @v dev 802.11 device
2387 * @v rc Return status code indicating reason
2388 *
2389 * The deauthentication will be sent using an 802.11 "unspecified
2390 * reason", as is common, but @a rc will be set as a link-up
2391 * error to aid the user in debugging.
2392 */
2393 void net80211_deauthenticate ( struct net80211_device *dev, int rc )
2394 {
2395 net80211_send_disassoc ( dev, IEEE80211_REASON_UNSPECIFIED, 1 );
2396 dev->assoc_rc = rc;
2397 netdev_link_err ( dev->netdev, rc );
2398
2399 net80211_autoassociate ( dev );
2400 }
2401
2402
2403 /** Smoothing factor (1-7) for link quality calculation */
2404 #define LQ_SMOOTH 7
2405
2406 /**
2407 * Update link quality information based on received beacon
2408 *
2409 * @v dev 802.11 device
2410 * @v iob I/O buffer containing beacon
2411 * @ret rc Return status code
2412 */
2413 static void net80211_update_link_quality ( struct net80211_device *dev,
2414 struct io_buffer *iob )
2415 {
2416 struct ieee80211_frame *hdr = iob->data;
2417 struct ieee80211_beacon *beacon;
2418 u32 dt, rxi;
2419
2420 if ( ! ( dev->state & NET80211_ASSOCIATED ) )
2421 return;
2422
2423 beacon = ( struct ieee80211_beacon * ) hdr->data;
2424 dt = ( u32 ) ( beacon->timestamp - dev->last_beacon_timestamp );
2425 rxi = dev->rx_beacon_interval;
2426
2427 rxi = ( LQ_SMOOTH * rxi ) + ( ( 8 - LQ_SMOOTH ) * dt );
2428 dev->rx_beacon_interval = rxi >> 3;
2429
2430 dev->last_beacon_timestamp = beacon->timestamp;
2431 }
2432
2433
2434 /**
2435 * Handle receipt of 802.11 management frame
2436 *
2437 * @v dev 802.11 device
2438 * @v iob I/O buffer
2439 * @v signal Signal strength of received frame
2440 */
2441 static void net80211_handle_mgmt ( struct net80211_device *dev,
2442 struct io_buffer *iob, int signal )
2443 {
2444 struct ieee80211_frame *hdr = iob->data;
2445 struct ieee80211_disassoc *disassoc;
2446 u16 stype = hdr->fc & IEEE80211_FC_SUBTYPE;
2447 int keep = 0;
2448 int is_deauth = ( stype == IEEE80211_STYPE_DEAUTH );
2449
2450 if ( ( hdr->fc & IEEE80211_FC_TYPE ) != IEEE80211_TYPE_MGMT ) {
2451 free_iob ( iob );
2452 return; /* only handle management frames */
2453 }
2454
2455 switch ( stype ) {
2456 /* We reconnect on deauthentication and disassociation. */
2457 case IEEE80211_STYPE_DEAUTH:
2458 case IEEE80211_STYPE_DISASSOC:
2459 disassoc = ( struct ieee80211_disassoc * ) hdr->data;
2460 net80211_set_state ( dev, is_deauth ? NET80211_AUTHENTICATED :
2461 NET80211_ASSOCIATED, 0,
2462 NET80211_IS_REASON | disassoc->reason );
2463 DBGC ( dev, "802.11 %p %s: reason %d\n",
2464 dev, is_deauth ? "deauthenticated" : "disassociated",
2465 disassoc->reason );
2466
2467 /* Try to reassociate, in case it's transient. */
2468 net80211_autoassociate ( dev );
2469
2470 break;
2471
2472 /* We handle authentication and association. */
2473 case IEEE80211_STYPE_AUTH:
2474 if ( ! ( dev->state & NET80211_AUTHENTICATED ) )
2475 net80211_handle_auth ( dev, iob );
2476 break;
2477
2478 case IEEE80211_STYPE_ASSOC_RESP:
2479 case IEEE80211_STYPE_REASSOC_RESP:
2480 if ( ! ( dev->state & NET80211_ASSOCIATED ) )
2481 net80211_handle_assoc_reply ( dev, iob );
2482 break;
2483
2484 /* We pass probes and beacons onto network scanning
2485 code. Pass actions for future extensibility. */
2486 case IEEE80211_STYPE_BEACON:
2487 net80211_update_link_quality ( dev, iob );
2488 /* fall through */
2489 case IEEE80211_STYPE_PROBE_RESP:
2490 case IEEE80211_STYPE_ACTION:
2491 if ( dev->keep_mgmt ) {
2492 struct net80211_rx_info *rxinf;
2493 rxinf = zalloc ( sizeof ( *rxinf ) );
2494 if ( ! rxinf ) {
2495 DBGC ( dev, "802.11 %p out of memory\n", dev );
2496 break;
2497 }
2498 rxinf->signal = signal;
2499 list_add_tail ( &iob->list, &dev->mgmt_queue );
2500 list_add_tail ( &rxinf->list, &dev->mgmt_info_queue );
2501 keep = 1;
2502 }
2503 break;
2504
2505 case IEEE80211_STYPE_PROBE_REQ:
2506 /* Some nodes send these broadcast. Ignore them. */
2507 break;
2508
2509 case IEEE80211_STYPE_ASSOC_REQ:
2510 case IEEE80211_STYPE_REASSOC_REQ:
2511 /* We should never receive these, only send them. */
2512 DBGC ( dev, "802.11 %p received strange management request "
2513 "(%04x)\n", dev, stype );
2514 break;
2515
2516 default:
2517 DBGC ( dev, "802.11 %p received unimplemented management "
2518 "packet (%04x)\n", dev, stype );
2519 break;
2520 }
2521
2522 if ( ! keep )
2523 free_iob ( iob );
2524 }
2525
2526 /* ---------- Packet handling functions ---------- */
2527
2528 /**
2529 * Free buffers used by 802.11 fragment cache entry
2530 *
2531 * @v dev 802.11 device
2532 * @v fcid Fragment cache entry index
2533 *
2534 * After this function, the referenced entry will be marked unused.
2535 */
2536 static void net80211_free_frags ( struct net80211_device *dev, int fcid )
2537 {
2538 int j;
2539 struct net80211_frag_cache *frag = &dev->frags[fcid];
2540
2541 for ( j = 0; j < 16; j++ ) {
2542 if ( frag->iob[j] ) {
2543 free_iob ( frag->iob[j] );
2544 frag->iob[j] = NULL;
2545 }
2546 }
2547
2548 frag->seqnr = 0;
2549 frag->start_ticks = 0;
2550 frag->in_use = 0;
2551 }
2552
2553 /**
2554 * Accumulate 802.11 fragments into one I/O buffer
2555 *
2556 * @v dev 802.11 device
2557 * @v fcid Fragment cache entry index
2558 * @v nfrags Number of fragments received
2559 * @v size Sum of sizes of all fragments, including headers
2560 * @ret iob I/O buffer containing reassembled packet
2561 *
2562 * This function does not free the fragment buffers.
2563 */
2564 static struct io_buffer *net80211_accum_frags ( struct net80211_device *dev,
2565 int fcid, int nfrags, int size )
2566 {
2567 struct net80211_frag_cache *frag = &dev->frags[fcid];
2568 int hdrsize = IEEE80211_TYP_FRAME_HEADER_LEN;
2569 int nsize = size - hdrsize * ( nfrags - 1 );
2570 int i;
2571
2572 struct io_buffer *niob = alloc_iob ( nsize );
2573 struct ieee80211_frame *hdr;
2574
2575 /* Add the header from the first one... */
2576 memcpy ( iob_put ( niob, hdrsize ), frag->iob[0]->data, hdrsize );
2577
2578 /* ... and all the data from all of them. */
2579 for ( i = 0; i < nfrags; i++ ) {
2580 int len = iob_len ( frag->iob[i] ) - hdrsize;
2581 memcpy ( iob_put ( niob, len ),
2582 frag->iob[i]->data + hdrsize, len );
2583 }
2584
2585 /* Turn off the fragment bit. */
2586 hdr = niob->data;
2587 hdr->fc &= ~IEEE80211_FC_MORE_FRAG;
2588
2589 return niob;
2590 }
2591
2592 /**
2593 * Handle receipt of 802.11 fragment
2594 *
2595 * @v dev 802.11 device
2596 * @v iob I/O buffer containing fragment
2597 * @v signal Signal strength with which fragment was received
2598 */
2599 static void net80211_rx_frag ( struct net80211_device *dev,
2600 struct io_buffer *iob, int signal )
2601 {
2602 struct ieee80211_frame *hdr = iob->data;
2603 int fragnr = IEEE80211_FRAG ( hdr->seq );
2604
2605 if ( fragnr == 0 && ( hdr->fc & IEEE80211_FC_MORE_FRAG ) ) {
2606 /* start a frag cache entry */
2607 int i, newest = -1;
2608 u32 curr_ticks = currticks(), newest_ticks = 0;
2609 u32 timeout = ticks_per_sec() * NET80211_FRAG_TIMEOUT;
2610
2611 for ( i = 0; i < NET80211_NR_CONCURRENT_FRAGS; i++ ) {
2612 if ( dev->frags[i].in_use == 0 )
2613 break;
2614
2615 if ( dev->frags[i].start_ticks + timeout >=
2616 curr_ticks ) {
2617 net80211_free_frags ( dev, i );
2618 break;
2619 }
2620
2621 if ( dev->frags[i].start_ticks > newest_ticks ) {
2622 newest = i;
2623 newest_ticks = dev->frags[i].start_ticks;
2624 }
2625 }
2626
2627 /* If we're being sent more concurrent fragmented
2628 packets than we can handle, drop the newest so the
2629 older ones have time to complete. */
2630 if ( i == NET80211_NR_CONCURRENT_FRAGS ) {
2631 i = newest;
2632 net80211_free_frags ( dev, i );
2633 }
2634
2635 dev->frags[i].in_use = 1;
2636 dev->frags[i].seqnr = IEEE80211_SEQNR ( hdr->seq );
2637 dev->frags[i].start_ticks = currticks();
2638 dev->frags[i].iob[0] = iob;
2639 return;
2640 } else {
2641 int i;
2642 for ( i = 0; i < NET80211_NR_CONCURRENT_FRAGS; i++ ) {
2643 if ( dev->frags[i].in_use && dev->frags[i].seqnr ==
2644 IEEE80211_SEQNR ( hdr->seq ) )
2645 break;
2646 }
2647 if ( i == NET80211_NR_CONCURRENT_FRAGS ) {
2648 /* Drop non-first not-in-cache fragments */
2649 DBGC ( dev, "802.11 %p dropped fragment fc=%04x "
2650 "seq=%04x\n", dev, hdr->fc, hdr->seq );
2651 free_iob ( iob );
2652 return;
2653 }
2654
2655 dev->frags[i].iob[fragnr] = iob;
2656
2657 if ( ! ( hdr->fc & IEEE80211_FC_MORE_FRAG ) ) {
2658 int j, size = 0;
2659 for ( j = 0; j < fragnr; j++ ) {
2660 size += iob_len ( dev->frags[i].iob[j] );
2661 if ( dev->frags[i].iob[j] == NULL )
2662 break;
2663 }
2664 if ( j == fragnr ) {
2665 /* We've got everything */
2666 struct io_buffer *niob =
2667 net80211_accum_frags ( dev, i, fragnr,
2668 size );
2669 net80211_free_frags ( dev, i );
2670 net80211_rx ( dev, niob, signal, 0 );
2671 } else {
2672 DBGC ( dev, "802.11 %p dropping fragmented "
2673 "packet due to out-of-order arrival, "
2674 "fc=%04x seq=%04x\n", dev, hdr->fc,
2675 hdr->seq );
2676 net80211_free_frags ( dev, i );
2677 }
2678 }
2679 }
2680 }
2681
2682 /**
2683 * Handle receipt of 802.11 frame
2684 *
2685 * @v dev 802.11 device
2686 * @v iob I/O buffer
2687 * @v signal Received signal strength
2688 * @v rate Bitrate at which frame was received, in 100 kbps units
2689 *
2690 * If the rate or signal is unknown, 0 should be passed.
2691 */
2692 void net80211_rx ( struct net80211_device *dev, struct io_buffer *iob,
2693 int signal, u16 rate )
2694 {
2695 struct ieee80211_frame *hdr = iob->data;
2696 u16 type = hdr->fc & IEEE80211_FC_TYPE;
2697 if ( ( hdr->fc & IEEE80211_FC_VERSION ) != IEEE80211_THIS_VERSION )
2698 goto drop; /* drop invalid-version packets */
2699
2700 if ( type == IEEE80211_TYPE_CTRL )
2701 goto drop; /* we don't handle control packets,
2702 the hardware does */
2703
2704 if ( dev->last_rx_seq == hdr->seq )
2705 goto drop; /* avoid duplicate packet */
2706 dev->last_rx_seq = hdr->seq;
2707
2708 if ( dev->hw->flags & NET80211_HW_RX_HAS_FCS ) {
2709 /* discard the FCS */
2710 iob_unput ( iob, 4 );
2711 }
2712
2713 /* Only decrypt packets from our BSSID, to avoid spurious errors */
2714 if ( ( hdr->fc & IEEE80211_FC_PROTECTED ) &&
2715 ! memcmp ( hdr->addr2, dev->bssid, ETH_ALEN ) ) {
2716 /* Decrypt packet; record and drop if it fails */
2717 struct io_buffer *niob;
2718 struct net80211_crypto *crypto = dev->crypto;
2719
2720 if ( ! dev->crypto ) {
2721 DBGC ( dev, "802.11 %p cannot decrypt packet "
2722 "without a cryptosystem\n", dev );
2723 goto drop_crypt;
2724 }
2725
2726 if ( ( hdr->addr1[0] & 1 ) && dev->gcrypto ) {
2727 /* Use group decryption if needed */
2728 crypto = dev->gcrypto;
2729 }
2730
2731 niob = crypto->decrypt ( crypto, iob );
2732 if ( ! niob ) {
2733 DBGC ( dev, "802.11 %p decryption error\n", dev );
2734 goto drop_crypt;
2735 }
2736 free_iob ( iob );
2737 iob = niob;
2738 hdr = iob->data;
2739 }
2740
2741 dev->last_signal = signal;
2742
2743 /* Fragments go into the frag cache or get dropped. */
2744 if ( IEEE80211_FRAG ( hdr->seq ) != 0
2745 || ( hdr->fc & IEEE80211_FC_MORE_FRAG ) ) {
2746 net80211_rx_frag ( dev, iob, signal );
2747 return;
2748 }
2749
2750 /* Management frames get handled, enqueued, or dropped. */
2751 if ( type == IEEE80211_TYPE_MGMT ) {
2752 net80211_handle_mgmt ( dev, iob, signal );
2753 return;
2754 }
2755
2756 /* Data frames get dropped or sent to the net_device. */
2757 if ( ( hdr->fc & IEEE80211_FC_SUBTYPE ) != IEEE80211_STYPE_DATA )
2758 goto drop; /* drop QoS, CFP, or null data packets */
2759
2760 /* Update rate-control algorithm */
2761 if ( dev->rctl )
2762 rc80211_update_rx ( dev, hdr->fc & IEEE80211_FC_RETRY, rate );
2763
2764 /* Pass packet onward */
2765 if ( dev->state & NET80211_ASSOCIATED ) {
2766 netdev_rx ( dev->netdev, iob );
2767 return;
2768 }
2769
2770 /* No association? Drop it. */
2771 goto drop;
2772
2773 drop_crypt:
2774 netdev_rx_err ( dev->netdev, NULL, EINVAL_CRYPTO_REQUEST );
2775 drop:
2776 DBGC2 ( dev, "802.11 %p dropped packet fc=%04x seq=%04x\n", dev,
2777 hdr->fc, hdr->seq );
2778 free_iob ( iob );
2779 return;
2780 }
2781
2782 /** Indicate an error in receiving a packet
2783 *
2784 * @v dev 802.11 device
2785 * @v iob I/O buffer with received packet, or NULL
2786 * @v rc Error code
2787 *
2788 * This logs the error with the wrapping net_device, and frees iob if
2789 * it is passed.
2790 */
2791 void net80211_rx_err ( struct net80211_device *dev,
2792 struct io_buffer *iob, int rc )
2793 {
2794 netdev_rx_err ( dev->netdev, iob, rc );
2795 }
2796
2797 /** Indicate the completed transmission of a packet
2798 *
2799 * @v dev 802.11 device
2800 * @v iob I/O buffer of transmitted packet
2801 * @v retries Number of times this packet was retransmitted
2802 * @v rc Error code, or 0 for success
2803 *
2804 * This logs an error with the wrapping net_device if one occurred,
2805 * and removes and frees the I/O buffer from its TX queue. The
2806 * provided retry information is used to tune our transmission rate.
2807 *
2808 * If the packet did not need to be retransmitted because it was
2809 * properly ACKed the first time, @a retries should be 0.
2810 */
2811 void net80211_tx_complete ( struct net80211_device *dev,
2812 struct io_buffer *iob, int retries, int rc )
2813 {
2814 /* Update rate-control algorithm */
2815 if ( dev->rctl )
2816 rc80211_update_tx ( dev, retries, rc );
2817
2818 /* Pass completion onward */
2819 netdev_tx_complete_err ( dev->netdev, iob, rc );
2820 }
2821
2822 /** Common 802.11 errors */
2823 struct errortab common_wireless_errors[] __errortab = {
2824 __einfo_errortab ( EINFO_EINVAL_CRYPTO_REQUEST ),
2825 __einfo_errortab ( EINFO_ECONNRESET_UNSPECIFIED ),
2826 __einfo_errortab ( EINFO_ECONNRESET_INACTIVITY ),
2827 __einfo_errortab ( EINFO_ECONNRESET_4WAY_TIMEOUT ),
2828 __einfo_errortab ( EINFO_ECONNRESET_8021X_FAILURE ),
2829 __einfo_errortab ( EINFO_ECONNREFUSED_FAILURE ),
2830 __einfo_errortab ( EINFO_ECONNREFUSED_ASSOC_DENIED ),
2831 __einfo_errortab ( EINFO_ECONNREFUSED_AUTH_ALGO_UNSUPP ),
2832 };
2833
2834 /* Drag in objects via net80211_ll_protocol */
2835 REQUIRING_SYMBOL ( net80211_ll_protocol );
2836
2837 /* Drag in 802.11 configuration */
2838 REQUIRE_OBJECT ( config_net80211 );