2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005-2006, Devicescape Software, Inc.
4 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
5 * Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * utilities for mac80211
14 #include <net/mac80211.h>
15 #include <linux/netdevice.h>
16 #include <linux/types.h>
17 #include <linux/slab.h>
18 #include <linux/skbuff.h>
19 #include <linux/etherdevice.h>
20 #include <linux/if_arp.h>
21 #include <linux/wireless.h>
22 #include <linux/bitmap.h>
23 #include <net/net_namespace.h>
24 #include <net/cfg80211.h>
25 #include <net/rtnetlink.h>
27 #include "ieee80211_i.h"
28 #include "ieee80211_rate.h"
31 /* privid for wiphys to determine whether they belong to us or not */
32 void *mac80211_wiphy_privid
= &mac80211_wiphy_privid
;
34 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
35 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
36 const unsigned char rfc1042_header
[] =
37 { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
39 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
40 const unsigned char bridge_tunnel_header
[] =
41 { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
44 static int rate_list_match(const int *rate_list
, int rate
)
51 for (i
= 0; rate_list
[i
] >= 0; i
++)
52 if (rate_list
[i
] == rate
)
58 void ieee80211_prepare_rates(struct ieee80211_local
*local
,
59 struct ieee80211_hw_mode
*mode
)
63 for (i
= 0; i
< mode
->num_rates
; i
++) {
64 struct ieee80211_rate
*rate
= &mode
->rates
[i
];
66 rate
->flags
&= ~(IEEE80211_RATE_SUPPORTED
|
67 IEEE80211_RATE_BASIC
);
69 if (local
->supp_rates
[mode
->mode
]) {
70 if (!rate_list_match(local
->supp_rates
[mode
->mode
],
75 rate
->flags
|= IEEE80211_RATE_SUPPORTED
;
77 /* Use configured basic rate set if it is available. If not,
78 * use defaults that are sane for most cases. */
79 if (local
->basic_rates
[mode
->mode
]) {
80 if (rate_list_match(local
->basic_rates
[mode
->mode
],
82 rate
->flags
|= IEEE80211_RATE_BASIC
;
83 } else switch (mode
->mode
) {
85 if (rate
->rate
== 60 || rate
->rate
== 120 ||
87 rate
->flags
|= IEEE80211_RATE_BASIC
;
90 if (rate
->rate
== 10 || rate
->rate
== 20)
91 rate
->flags
|= IEEE80211_RATE_BASIC
;
94 if (rate
->rate
== 10 || rate
->rate
== 20 ||
95 rate
->rate
== 55 || rate
->rate
== 110)
96 rate
->flags
|= IEEE80211_RATE_BASIC
;
98 case NUM_IEEE80211_MODES
:
103 /* Set ERP and MANDATORY flags based on phymode */
104 switch (mode
->mode
) {
105 case MODE_IEEE80211A
:
106 if (rate
->rate
== 60 || rate
->rate
== 120 ||
108 rate
->flags
|= IEEE80211_RATE_MANDATORY
;
110 case MODE_IEEE80211B
:
111 if (rate
->rate
== 10)
112 rate
->flags
|= IEEE80211_RATE_MANDATORY
;
114 case MODE_IEEE80211G
:
115 if (rate
->rate
== 10 || rate
->rate
== 20 ||
116 rate
->rate
== 55 || rate
->rate
== 110 ||
117 rate
->rate
== 60 || rate
->rate
== 120 ||
119 rate
->flags
|= IEEE80211_RATE_MANDATORY
;
121 case NUM_IEEE80211_MODES
:
125 if (ieee80211_is_erp_rate(mode
->mode
, rate
->rate
))
126 rate
->flags
|= IEEE80211_RATE_ERP
;
130 u8
*ieee80211_get_bssid(struct ieee80211_hdr
*hdr
, size_t len
)
134 /* drop ACK/CTS frames and incorrect hdr len (ctrl) */
138 fc
= le16_to_cpu(hdr
->frame_control
);
140 switch (fc
& IEEE80211_FCTL_FTYPE
) {
141 case IEEE80211_FTYPE_DATA
:
142 if (len
< 24) /* drop incorrect hdr len (data) */
144 switch (fc
& (IEEE80211_FCTL_TODS
| IEEE80211_FCTL_FROMDS
)) {
145 case IEEE80211_FCTL_TODS
:
147 case (IEEE80211_FCTL_TODS
| IEEE80211_FCTL_FROMDS
):
149 case IEEE80211_FCTL_FROMDS
:
155 case IEEE80211_FTYPE_MGMT
:
156 if (len
< 24) /* drop incorrect hdr len (mgmt) */
159 case IEEE80211_FTYPE_CTL
:
160 if ((fc
& IEEE80211_FCTL_STYPE
) == IEEE80211_STYPE_PSPOLL
)
169 int ieee80211_get_hdrlen(u16 fc
)
173 switch (fc
& IEEE80211_FCTL_FTYPE
) {
174 case IEEE80211_FTYPE_DATA
:
175 if ((fc
& IEEE80211_FCTL_FROMDS
) && (fc
& IEEE80211_FCTL_TODS
))
176 hdrlen
= 30; /* Addr4 */
178 * The QoS Control field is two bytes and its presence is
179 * indicated by the IEEE80211_STYPE_QOS_DATA bit. Add 2 to
180 * hdrlen if that bit is set.
181 * This works by masking out the bit and shifting it to
182 * bit position 1 so the result has the value 0 or 2.
184 hdrlen
+= (fc
& IEEE80211_STYPE_QOS_DATA
)
185 >> (ilog2(IEEE80211_STYPE_QOS_DATA
)-1);
187 case IEEE80211_FTYPE_CTL
:
189 * ACK and CTS are 10 bytes, all others 16. To see how
190 * to get this condition consider
191 * subtype mask: 0b0000000011110000 (0x00F0)
192 * ACK subtype: 0b0000000011010000 (0x00D0)
193 * CTS subtype: 0b0000000011000000 (0x00C0)
194 * bits that matter: ^^^ (0x00E0)
195 * value of those: 0b0000000011000000 (0x00C0)
197 if ((fc
& 0xE0) == 0xC0)
206 EXPORT_SYMBOL(ieee80211_get_hdrlen
);
208 int ieee80211_get_hdrlen_from_skb(const struct sk_buff
*skb
)
210 const struct ieee80211_hdr
*hdr
= (const struct ieee80211_hdr
*) skb
->data
;
213 if (unlikely(skb
->len
< 10))
215 hdrlen
= ieee80211_get_hdrlen(le16_to_cpu(hdr
->frame_control
));
216 if (unlikely(hdrlen
> skb
->len
))
220 EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb
);
222 void ieee80211_tx_set_iswep(struct ieee80211_txrx_data
*tx
)
224 struct ieee80211_hdr
*hdr
= (struct ieee80211_hdr
*) tx
->skb
->data
;
226 hdr
->frame_control
|= cpu_to_le16(IEEE80211_FCTL_PROTECTED
);
227 if (tx
->u
.tx
.extra_frag
) {
228 struct ieee80211_hdr
*fhdr
;
230 for (i
= 0; i
< tx
->u
.tx
.num_extra_frag
; i
++) {
231 fhdr
= (struct ieee80211_hdr
*)
232 tx
->u
.tx
.extra_frag
[i
]->data
;
233 fhdr
->frame_control
|= cpu_to_le16(IEEE80211_FCTL_PROTECTED
);
238 int ieee80211_frame_duration(struct ieee80211_local
*local
, size_t len
,
239 int rate
, int erp
, int short_preamble
)
243 /* calculate duration (in microseconds, rounded up to next higher
244 * integer if it includes a fractional microsecond) to send frame of
245 * len bytes (does not include FCS) at the given rate. Duration will
248 * rate is in 100 kbps, so divident is multiplied by 10 in the
249 * DIV_ROUND_UP() operations.
252 if (local
->hw
.conf
.phymode
== MODE_IEEE80211A
|| erp
) {
256 * N_DBPS = DATARATE x 4
257 * N_SYM = Ceiling((16+8xLENGTH+6) / N_DBPS)
258 * (16 = SIGNAL time, 6 = tail bits)
259 * TXTIME = T_PREAMBLE + T_SIGNAL + T_SYM x N_SYM + Signal Ext
262 * 802.11a - 17.5.2: aSIFSTime = 16 usec
263 * 802.11g - 19.8.4: aSIFSTime = 10 usec +
264 * signal ext = 6 usec
266 dur
= 16; /* SIFS + signal ext */
267 dur
+= 16; /* 17.3.2.3: T_PREAMBLE = 16 usec */
268 dur
+= 4; /* 17.3.2.3: T_SIGNAL = 4 usec */
269 dur
+= 4 * DIV_ROUND_UP((16 + 8 * (len
+ 4) + 6) * 10,
270 4 * rate
); /* T_SYM x N_SYM */
273 * 802.11b or 802.11g with 802.11b compatibility:
274 * 18.3.4: TXTIME = PreambleLength + PLCPHeaderTime +
275 * Ceiling(((LENGTH+PBCC)x8)/DATARATE). PBCC=0.
277 * 802.11 (DS): 15.3.3, 802.11b: 18.3.4
278 * aSIFSTime = 10 usec
279 * aPreambleLength = 144 usec or 72 usec with short preamble
280 * aPLCPHeaderLength = 48 usec or 24 usec with short preamble
282 dur
= 10; /* aSIFSTime = 10 usec */
283 dur
+= short_preamble
? (72 + 24) : (144 + 48);
285 dur
+= DIV_ROUND_UP(8 * (len
+ 4) * 10, rate
);
291 /* Exported duration function for driver use */
292 __le16
ieee80211_generic_frame_duration(struct ieee80211_hw
*hw
, int if_id
,
293 size_t frame_len
, int rate
)
295 struct ieee80211_local
*local
= hw_to_local(hw
);
296 struct net_device
*bdev
= dev_get_by_index(&init_net
, if_id
);
297 struct ieee80211_sub_if_data
*sdata
;
304 sdata
= IEEE80211_DEV_TO_SUB_IF(bdev
);
305 erp
= ieee80211_is_erp_rate(hw
->conf
.phymode
, rate
);
306 dur
= ieee80211_frame_duration(local
, frame_len
, rate
,
307 erp
, sdata
->flags
& IEEE80211_SDATA_SHORT_PREAMBLE
);
310 return cpu_to_le16(dur
);
312 EXPORT_SYMBOL(ieee80211_generic_frame_duration
);
314 __le16
ieee80211_rts_duration(struct ieee80211_hw
*hw
, int if_id
,
316 const struct ieee80211_tx_control
*frame_txctl
)
318 struct ieee80211_local
*local
= hw_to_local(hw
);
319 struct ieee80211_rate
*rate
;
320 struct net_device
*bdev
= dev_get_by_index(&init_net
, if_id
);
321 struct ieee80211_sub_if_data
*sdata
;
329 sdata
= IEEE80211_DEV_TO_SUB_IF(bdev
);
330 short_preamble
= sdata
->flags
& IEEE80211_SDATA_SHORT_PREAMBLE
;
332 rate
= frame_txctl
->rts_rate
;
333 erp
= !!(rate
->flags
& IEEE80211_RATE_ERP
);
336 dur
= ieee80211_frame_duration(local
, 10, rate
->rate
,
337 erp
, short_preamble
);
338 /* Data frame duration */
339 dur
+= ieee80211_frame_duration(local
, frame_len
, rate
->rate
,
340 erp
, short_preamble
);
342 dur
+= ieee80211_frame_duration(local
, 10, rate
->rate
,
343 erp
, short_preamble
);
346 return cpu_to_le16(dur
);
348 EXPORT_SYMBOL(ieee80211_rts_duration
);
350 __le16
ieee80211_ctstoself_duration(struct ieee80211_hw
*hw
, int if_id
,
352 const struct ieee80211_tx_control
*frame_txctl
)
354 struct ieee80211_local
*local
= hw_to_local(hw
);
355 struct ieee80211_rate
*rate
;
356 struct net_device
*bdev
= dev_get_by_index(&init_net
, if_id
);
357 struct ieee80211_sub_if_data
*sdata
;
365 sdata
= IEEE80211_DEV_TO_SUB_IF(bdev
);
366 short_preamble
= sdata
->flags
& IEEE80211_SDATA_SHORT_PREAMBLE
;
368 rate
= frame_txctl
->rts_rate
;
369 erp
= !!(rate
->flags
& IEEE80211_RATE_ERP
);
371 /* Data frame duration */
372 dur
= ieee80211_frame_duration(local
, frame_len
, rate
->rate
,
373 erp
, short_preamble
);
374 if (!(frame_txctl
->flags
& IEEE80211_TXCTL_NO_ACK
)) {
376 dur
+= ieee80211_frame_duration(local
, 10, rate
->rate
,
377 erp
, short_preamble
);
381 return cpu_to_le16(dur
);
383 EXPORT_SYMBOL(ieee80211_ctstoself_duration
);
385 struct ieee80211_rate
*
386 ieee80211_get_rate(struct ieee80211_local
*local
, int phymode
, int hw_rate
)
388 struct ieee80211_hw_mode
*mode
;
391 list_for_each_entry(mode
, &local
->modes_list
, list
) {
392 if (mode
->mode
!= phymode
)
394 for (r
= 0; r
< mode
->num_rates
; r
++) {
395 struct ieee80211_rate
*rate
= &mode
->rates
[r
];
396 if (rate
->val
== hw_rate
||
397 (rate
->flags
& IEEE80211_RATE_PREAMBLE2
&&
398 rate
->val2
== hw_rate
))
406 void ieee80211_wake_queue(struct ieee80211_hw
*hw
, int queue
)
408 struct ieee80211_local
*local
= hw_to_local(hw
);
410 if (test_and_clear_bit(IEEE80211_LINK_STATE_XOFF
,
411 &local
->state
[queue
])) {
412 if (test_bit(IEEE80211_LINK_STATE_PENDING
,
413 &local
->state
[queue
]))
414 tasklet_schedule(&local
->tx_pending_tasklet
);
416 if (!ieee80211_qdisc_installed(local
->mdev
)) {
418 netif_wake_queue(local
->mdev
);
420 __netif_schedule(local
->mdev
);
423 EXPORT_SYMBOL(ieee80211_wake_queue
);
425 void ieee80211_stop_queue(struct ieee80211_hw
*hw
, int queue
)
427 struct ieee80211_local
*local
= hw_to_local(hw
);
429 if (!ieee80211_qdisc_installed(local
->mdev
) && queue
== 0)
430 netif_stop_queue(local
->mdev
);
431 set_bit(IEEE80211_LINK_STATE_XOFF
, &local
->state
[queue
]);
433 EXPORT_SYMBOL(ieee80211_stop_queue
);
435 void ieee80211_start_queues(struct ieee80211_hw
*hw
)
437 struct ieee80211_local
*local
= hw_to_local(hw
);
440 for (i
= 0; i
< local
->hw
.queues
; i
++)
441 clear_bit(IEEE80211_LINK_STATE_XOFF
, &local
->state
[i
]);
442 if (!ieee80211_qdisc_installed(local
->mdev
))
443 netif_start_queue(local
->mdev
);
445 EXPORT_SYMBOL(ieee80211_start_queues
);
447 void ieee80211_stop_queues(struct ieee80211_hw
*hw
)
451 for (i
= 0; i
< hw
->queues
; i
++)
452 ieee80211_stop_queue(hw
, i
);
454 EXPORT_SYMBOL(ieee80211_stop_queues
);
456 void ieee80211_wake_queues(struct ieee80211_hw
*hw
)
460 for (i
= 0; i
< hw
->queues
; i
++)
461 ieee80211_wake_queue(hw
, i
);
463 EXPORT_SYMBOL(ieee80211_wake_queues
);
465 void ieee80211_iterate_active_interfaces(struct ieee80211_hw
*hw
,
466 void (*iterator
)(void *data
, u8
*mac
,
470 struct ieee80211_local
*local
= hw_to_local(hw
);
471 struct ieee80211_sub_if_data
*sdata
;
475 list_for_each_entry_rcu(sdata
, &local
->interfaces
, list
) {
476 switch (sdata
->type
) {
477 case IEEE80211_IF_TYPE_INVALID
:
478 case IEEE80211_IF_TYPE_MNTR
:
479 case IEEE80211_IF_TYPE_VLAN
:
481 case IEEE80211_IF_TYPE_AP
:
482 case IEEE80211_IF_TYPE_STA
:
483 case IEEE80211_IF_TYPE_IBSS
:
484 case IEEE80211_IF_TYPE_WDS
:
487 if (sdata
->dev
== local
->mdev
)
489 if (netif_running(sdata
->dev
))
490 iterator(data
, sdata
->dev
->dev_addr
,
491 sdata
->dev
->ifindex
);
496 EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces
);