2 * Copyright (c) 2008 open80211s Ltd.
3 * Author: Luis Carlos Cobo <luisca@cozybit.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
9 #include <linux/kernel.h>
10 #include <linux/random.h>
11 #include "ieee80211_i.h"
15 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
16 #define mpl_dbg(fmt, args...) printk(KERN_DEBUG fmt, ##args)
18 #define mpl_dbg(fmt, args...) do { (void)(0); } while (0)
21 #define PLINK_GET_FRAME_SUBTYPE(p) (p)
22 #define PLINK_GET_LLID(p) (p + 1)
23 #define PLINK_GET_PLID(p) (p + 3)
25 #define mod_plink_timer(s, t) (mod_timer(&s->plink_timer, \
26 jiffies + HZ * t / 1000))
28 /* Peer link cancel reasons, all subject to ANA approval */
29 #define MESH_LINK_CANCELLED 2
30 #define MESH_MAX_NEIGHBORS 3
31 #define MESH_CAPABILITY_POLICY_VIOLATION 4
32 #define MESH_CLOSE_RCVD 5
33 #define MESH_MAX_RETRIES 6
34 #define MESH_CONFIRM_TIMEOUT 7
35 #define MESH_SECURITY_ROLE_NEGOTIATION_DIFFERS 8
36 #define MESH_SECURITY_AUTHENTICATION_IMPOSSIBLE 9
37 #define MESH_SECURITY_FAILED_VERIFICATION 10
39 #define dot11MeshMaxRetries(s) (s->u.mesh.mshcfg.dot11MeshMaxRetries)
40 #define dot11MeshRetryTimeout(s) (s->u.mesh.mshcfg.dot11MeshRetryTimeout)
41 #define dot11MeshConfirmTimeout(s) (s->u.mesh.mshcfg.dot11MeshConfirmTimeout)
42 #define dot11MeshHoldingTimeout(s) (s->u.mesh.mshcfg.dot11MeshHoldingTimeout)
43 #define dot11MeshMaxPeerLinks(s) (s->u.mesh.mshcfg.dot11MeshMaxPeerLinks)
45 enum plink_frame_type
{
64 void mesh_plink_inc_estab_count(struct ieee80211_sub_if_data
*sdata
)
66 atomic_inc(&sdata
->u
.mesh
.mshstats
.estab_plinks
);
67 mesh_accept_plinks_update(sdata
);
71 void mesh_plink_dec_estab_count(struct ieee80211_sub_if_data
*sdata
)
73 atomic_dec(&sdata
->u
.mesh
.mshstats
.estab_plinks
);
74 mesh_accept_plinks_update(sdata
);
78 * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
80 * @sta: mes peer link to restart
82 * Locking: this function must be called holding sta->lock
84 static inline void mesh_plink_fsm_restart(struct sta_info
*sta
)
86 sta
->plink_state
= PLINK_LISTEN
;
87 sta
->llid
= sta
->plid
= sta
->reason
= 0;
88 sta
->plink_retries
= 0;
92 * NOTE: This is just an alias for sta_info_alloc(), see notes
93 * on it in the lifecycle management section!
95 static struct sta_info
*mesh_plink_alloc(struct ieee80211_sub_if_data
*sdata
,
96 u8
*hw_addr
, u64 rates
)
98 struct ieee80211_local
*local
= sdata
->local
;
101 if (local
->num_sta
>= MESH_MAX_PLINKS
)
104 sta
= sta_info_alloc(sdata
, hw_addr
, GFP_ATOMIC
);
108 sta
->flags
= WLAN_STA_AUTHORIZED
;
109 sta
->sta
.supp_rates
[local
->hw
.conf
.channel
->band
] = rates
;
110 rate_control_rate_init(sta
);
116 * mesh_plink_deactivate - deactivate mesh peer link
118 * @sta: mesh peer link to deactivate
120 * All mesh paths with this peer as next hop will be flushed
122 * Locking: the caller must hold sta->lock
124 static void __mesh_plink_deactivate(struct sta_info
*sta
)
126 struct ieee80211_sub_if_data
*sdata
= sta
->sdata
;
128 if (sta
->plink_state
== PLINK_ESTAB
)
129 mesh_plink_dec_estab_count(sdata
);
130 sta
->plink_state
= PLINK_BLOCKED
;
131 mesh_path_flush_by_nexthop(sta
);
135 * __mesh_plink_deactivate - deactivate mesh peer link
137 * @sta: mesh peer link to deactivate
139 * All mesh paths with this peer as next hop will be flushed
141 void mesh_plink_deactivate(struct sta_info
*sta
)
143 spin_lock_bh(&sta
->lock
);
144 __mesh_plink_deactivate(sta
);
145 spin_unlock_bh(&sta
->lock
);
148 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data
*sdata
,
149 enum plink_frame_type action
, u8
*da
, __le16 llid
, __le16 plid
,
151 struct ieee80211_local
*local
= sdata
->local
;
152 struct sk_buff
*skb
= dev_alloc_skb(local
->hw
.extra_tx_headroom
+ 400);
153 struct ieee80211_mgmt
*mgmt
;
154 bool include_plid
= false;
160 skb_reserve(skb
, local
->hw
.extra_tx_headroom
);
161 /* 25 is the size of the common mgmt part (24) plus the size of the
162 * common action part (1)
164 mgmt
= (struct ieee80211_mgmt
*)
165 skb_put(skb
, 25 + sizeof(mgmt
->u
.action
.u
.plink_action
));
166 memset(mgmt
, 0, 25 + sizeof(mgmt
->u
.action
.u
.plink_action
));
167 mgmt
->frame_control
= cpu_to_le16(IEEE80211_FTYPE_MGMT
|
168 IEEE80211_STYPE_ACTION
);
169 memcpy(mgmt
->da
, da
, ETH_ALEN
);
170 memcpy(mgmt
->sa
, sdata
->dev
->dev_addr
, ETH_ALEN
);
171 /* BSSID is left zeroed, wildcard value */
172 mgmt
->u
.action
.category
= PLINK_CATEGORY
;
173 mgmt
->u
.action
.u
.plink_action
.action_code
= action
;
175 if (action
== PLINK_CLOSE
)
176 mgmt
->u
.action
.u
.plink_action
.aux
= reason
;
178 mgmt
->u
.action
.u
.plink_action
.aux
= cpu_to_le16(0x0);
179 if (action
== PLINK_CONFIRM
) {
180 pos
= skb_put(skb
, 4);
181 /* two-byte status code followed by two-byte AID */
184 mesh_mgmt_ies_add(skb
, sdata
);
187 /* Add Peer Link Management element */
207 pos
= skb_put(skb
, 2 + ie_len
);
208 *pos
++ = WLAN_EID_PEER_LINK
;
211 memcpy(pos
, &llid
, 2);
214 memcpy(pos
, &plid
, 2);
216 if (action
== PLINK_CLOSE
) {
218 memcpy(pos
, &reason
, 2);
221 ieee80211_tx_skb(sdata
, skb
, 0);
225 void mesh_neighbour_update(u8
*hw_addr
, u64 rates
, struct ieee80211_sub_if_data
*sdata
,
226 bool peer_accepting_plinks
)
228 struct ieee80211_local
*local
= sdata
->local
;
229 struct sta_info
*sta
;
233 sta
= sta_info_get(local
, hw_addr
);
235 sta
= mesh_plink_alloc(sdata
, hw_addr
, rates
);
240 if (sta_info_insert(sta
)) {
246 sta
->last_rx
= jiffies
;
247 sta
->sta
.supp_rates
[local
->hw
.conf
.channel
->band
] = rates
;
248 if (peer_accepting_plinks
&& sta
->plink_state
== PLINK_LISTEN
&&
249 sdata
->u
.mesh
.accepting_plinks
&&
250 sdata
->u
.mesh
.mshcfg
.auto_open_plinks
)
251 mesh_plink_open(sta
);
256 static void mesh_plink_timer(unsigned long data
)
258 struct sta_info
*sta
;
259 __le16 llid
, plid
, reason
;
260 struct ieee80211_sub_if_data
*sdata
;
263 * This STA is valid because sta_info_destroy() will
264 * del_timer_sync() this timer after having made sure
265 * it cannot be readded (by deleting the plink.)
267 sta
= (struct sta_info
*) data
;
269 spin_lock_bh(&sta
->lock
);
270 if (sta
->ignore_plink_timer
) {
271 sta
->ignore_plink_timer
= false;
272 spin_unlock_bh(&sta
->lock
);
275 mpl_dbg("Mesh plink timer for %pM fired on state %d\n",
276 sta
->sta
.addr
, sta
->plink_state
);
282 switch (sta
->plink_state
) {
286 if (sta
->plink_retries
< dot11MeshMaxRetries(sdata
)) {
288 mpl_dbg("Mesh plink for %pM (retry, timeout): %d %d\n",
289 sta
->sta
.addr
, sta
->plink_retries
,
291 get_random_bytes(&rand
, sizeof(u32
));
292 sta
->plink_timeout
= sta
->plink_timeout
+
293 rand
% sta
->plink_timeout
;
294 ++sta
->plink_retries
;
295 mod_plink_timer(sta
, sta
->plink_timeout
);
296 spin_unlock_bh(&sta
->lock
);
297 mesh_plink_frame_tx(sdata
, PLINK_OPEN
, sta
->sta
.addr
, llid
,
301 reason
= cpu_to_le16(MESH_MAX_RETRIES
);
302 /* fall through on else */
306 reason
= cpu_to_le16(MESH_CONFIRM_TIMEOUT
);
307 sta
->plink_state
= PLINK_HOLDING
;
308 mod_plink_timer(sta
, dot11MeshHoldingTimeout(sdata
));
309 spin_unlock_bh(&sta
->lock
);
310 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
, llid
, plid
,
315 del_timer(&sta
->plink_timer
);
316 mesh_plink_fsm_restart(sta
);
317 spin_unlock_bh(&sta
->lock
);
320 spin_unlock_bh(&sta
->lock
);
325 static inline void mesh_plink_timer_set(struct sta_info
*sta
, int timeout
)
327 sta
->plink_timer
.expires
= jiffies
+ (HZ
* timeout
/ 1000);
328 sta
->plink_timer
.data
= (unsigned long) sta
;
329 sta
->plink_timer
.function
= mesh_plink_timer
;
330 sta
->plink_timeout
= timeout
;
331 add_timer(&sta
->plink_timer
);
334 int mesh_plink_open(struct sta_info
*sta
)
337 struct ieee80211_sub_if_data
*sdata
= sta
->sdata
;
339 spin_lock_bh(&sta
->lock
);
340 get_random_bytes(&llid
, 2);
342 if (sta
->plink_state
!= PLINK_LISTEN
) {
343 spin_unlock_bh(&sta
->lock
);
346 sta
->plink_state
= PLINK_OPN_SNT
;
347 mesh_plink_timer_set(sta
, dot11MeshRetryTimeout(sdata
));
348 spin_unlock_bh(&sta
->lock
);
349 mpl_dbg("Mesh plink: starting establishment with %pM\n",
352 return mesh_plink_frame_tx(sdata
, PLINK_OPEN
,
353 sta
->sta
.addr
, llid
, 0, 0);
356 void mesh_plink_block(struct sta_info
*sta
)
358 spin_lock_bh(&sta
->lock
);
359 __mesh_plink_deactivate(sta
);
360 sta
->plink_state
= PLINK_BLOCKED
;
361 spin_unlock_bh(&sta
->lock
);
364 int mesh_plink_close(struct sta_info
*sta
)
366 struct ieee80211_sub_if_data
*sdata
= sta
->sdata
;
367 __le16 llid
, plid
, reason
;
369 mpl_dbg("Mesh plink: closing link with %pM\n", sta
->sta
.addr
);
370 spin_lock_bh(&sta
->lock
);
371 sta
->reason
= cpu_to_le16(MESH_LINK_CANCELLED
);
372 reason
= sta
->reason
;
374 if (sta
->plink_state
== PLINK_LISTEN
||
375 sta
->plink_state
== PLINK_BLOCKED
) {
376 mesh_plink_fsm_restart(sta
);
377 spin_unlock_bh(&sta
->lock
);
379 } else if (sta
->plink_state
== PLINK_ESTAB
) {
380 __mesh_plink_deactivate(sta
);
381 /* The timer should not be running */
382 mod_plink_timer(sta
, dot11MeshHoldingTimeout(sdata
));
383 } else if (!mod_plink_timer(sta
, dot11MeshHoldingTimeout(sdata
)))
384 sta
->ignore_plink_timer
= true;
386 sta
->plink_state
= PLINK_HOLDING
;
389 spin_unlock_bh(&sta
->lock
);
390 mesh_plink_frame_tx(sta
->sdata
, PLINK_CLOSE
, sta
->sta
.addr
, llid
,
395 void mesh_rx_plink_frame(struct ieee80211_sub_if_data
*sdata
, struct ieee80211_mgmt
*mgmt
,
396 size_t len
, struct ieee80211_rx_status
*rx_status
)
398 struct ieee80211_local
*local
= sdata
->local
;
399 struct ieee802_11_elems elems
;
400 struct sta_info
*sta
;
401 enum plink_event event
;
402 enum plink_frame_type ftype
;
406 __le16 plid
, llid
, reason
;
408 /* need action_code, aux */
409 if (len
< IEEE80211_MIN_ACTION_SIZE
+ 3)
412 if (is_multicast_ether_addr(mgmt
->da
)) {
413 mpl_dbg("Mesh plink: ignore frame from multicast address");
417 baseaddr
= mgmt
->u
.action
.u
.plink_action
.variable
;
418 baselen
= (u8
*) mgmt
->u
.action
.u
.plink_action
.variable
- (u8
*) mgmt
;
419 if (mgmt
->u
.action
.u
.plink_action
.action_code
== PLINK_CONFIRM
) {
423 ieee802_11_parse_elems(baseaddr
, len
- baselen
, &elems
);
424 if (!elems
.peer_link
) {
425 mpl_dbg("Mesh plink: missing necessary peer link ie\n");
429 ftype
= *((u8
*)PLINK_GET_FRAME_SUBTYPE(elems
.peer_link
));
430 ie_len
= elems
.peer_link_len
;
431 if ((ftype
== PLINK_OPEN
&& ie_len
!= 3) ||
432 (ftype
== PLINK_CONFIRM
&& ie_len
!= 5) ||
433 (ftype
== PLINK_CLOSE
&& ie_len
!= 5 && ie_len
!= 7)) {
434 mpl_dbg("Mesh plink: incorrect plink ie length\n");
438 if (ftype
!= PLINK_CLOSE
&& (!elems
.mesh_id
|| !elems
.mesh_config
)) {
439 mpl_dbg("Mesh plink: missing necessary ie\n");
442 /* Note the lines below are correct, the llid in the frame is the plid
443 * from the point of view of this host.
445 memcpy(&plid
, PLINK_GET_LLID(elems
.peer_link
), 2);
446 if (ftype
== PLINK_CONFIRM
|| (ftype
== PLINK_CLOSE
&& ie_len
== 7))
447 memcpy(&llid
, PLINK_GET_PLID(elems
.peer_link
), 2);
451 sta
= sta_info_get(local
, mgmt
->sa
);
452 if (!sta
&& ftype
!= PLINK_OPEN
) {
453 mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
458 if (sta
&& sta
->plink_state
== PLINK_BLOCKED
) {
463 /* Now we will figure out the appropriate event... */
464 event
= PLINK_UNDEFINED
;
465 if (ftype
!= PLINK_CLOSE
&& (!mesh_matches_local(&elems
, sdata
))) {
477 spin_lock_bh(&sta
->lock
);
479 /* ftype == PLINK_OPEN */
481 if (!mesh_plink_free_count(sdata
)) {
482 mpl_dbg("Mesh plink error: no more free plinks\n");
487 rates
= ieee80211_sta_get_rates(local
, &elems
, rx_status
->band
);
488 sta
= mesh_plink_alloc(sdata
, mgmt
->sa
, rates
);
490 mpl_dbg("Mesh plink error: plink table full\n");
494 if (sta_info_insert(sta
)) {
499 spin_lock_bh(&sta
->lock
);
501 spin_lock_bh(&sta
->lock
);
504 if (!mesh_plink_free_count(sdata
) ||
505 (sta
->plid
&& sta
->plid
!= plid
))
511 if (!mesh_plink_free_count(sdata
) ||
512 (sta
->llid
!= llid
|| sta
->plid
!= plid
))
518 if (sta
->plink_state
== PLINK_ESTAB
)
519 /* Do not check for llid or plid. This does not
520 * follow the standard but since multiple plinks
521 * per sta are not supported, it is necessary in
522 * order to avoid a livelock when MP A sees an
523 * establish peer link to MP B but MP B does not
524 * see it. This can be caused by a timeout in
525 * B's peer link establishment or B beign
529 else if (sta
->plid
!= plid
)
531 else if (ie_len
== 7 && sta
->llid
!= llid
)
537 mpl_dbg("Mesh plink: unknown frame subtype\n");
538 spin_unlock_bh(&sta
->lock
);
544 mpl_dbg("Mesh plink (peer, state, llid, plid, event): %pM %d %d %d %d\n",
545 mgmt
->sa
, sta
->plink_state
,
546 le16_to_cpu(sta
->llid
), le16_to_cpu(sta
->plid
),
549 switch (sta
->plink_state
) {
550 /* spin_unlock as soon as state is updated at each case */
554 mesh_plink_fsm_restart(sta
);
555 spin_unlock_bh(&sta
->lock
);
558 sta
->plink_state
= PLINK_OPN_RCVD
;
560 get_random_bytes(&llid
, 2);
562 mesh_plink_timer_set(sta
, dot11MeshRetryTimeout(sdata
));
563 spin_unlock_bh(&sta
->lock
);
564 mesh_plink_frame_tx(sdata
, PLINK_OPEN
, sta
->sta
.addr
, llid
,
566 mesh_plink_frame_tx(sdata
, PLINK_CONFIRM
, sta
->sta
.addr
,
570 spin_unlock_bh(&sta
->lock
);
579 reason
= cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION
);
582 reason
= cpu_to_le16(MESH_CLOSE_RCVD
);
583 sta
->reason
= reason
;
584 sta
->plink_state
= PLINK_HOLDING
;
585 if (!mod_plink_timer(sta
,
586 dot11MeshHoldingTimeout(sdata
)))
587 sta
->ignore_plink_timer
= true;
590 spin_unlock_bh(&sta
->lock
);
591 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
, llid
,
595 /* retry timer is left untouched */
596 sta
->plink_state
= PLINK_OPN_RCVD
;
599 spin_unlock_bh(&sta
->lock
);
600 mesh_plink_frame_tx(sdata
, PLINK_CONFIRM
, sta
->sta
.addr
, llid
,
604 sta
->plink_state
= PLINK_CNF_RCVD
;
605 if (!mod_plink_timer(sta
,
606 dot11MeshConfirmTimeout(sdata
)))
607 sta
->ignore_plink_timer
= true;
609 spin_unlock_bh(&sta
->lock
);
612 spin_unlock_bh(&sta
->lock
);
621 reason
= cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION
);
624 reason
= cpu_to_le16(MESH_CLOSE_RCVD
);
625 sta
->reason
= reason
;
626 sta
->plink_state
= PLINK_HOLDING
;
627 if (!mod_plink_timer(sta
,
628 dot11MeshHoldingTimeout(sdata
)))
629 sta
->ignore_plink_timer
= true;
632 spin_unlock_bh(&sta
->lock
);
633 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
, llid
,
638 spin_unlock_bh(&sta
->lock
);
639 mesh_plink_frame_tx(sdata
, PLINK_CONFIRM
, sta
->sta
.addr
, llid
,
643 del_timer(&sta
->plink_timer
);
644 sta
->plink_state
= PLINK_ESTAB
;
645 mesh_plink_inc_estab_count(sdata
);
646 spin_unlock_bh(&sta
->lock
);
647 mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
651 spin_unlock_bh(&sta
->lock
);
660 reason
= cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION
);
663 reason
= cpu_to_le16(MESH_CLOSE_RCVD
);
664 sta
->reason
= reason
;
665 sta
->plink_state
= PLINK_HOLDING
;
666 if (!mod_plink_timer(sta
,
667 dot11MeshHoldingTimeout(sdata
)))
668 sta
->ignore_plink_timer
= true;
671 spin_unlock_bh(&sta
->lock
);
672 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
, llid
,
676 del_timer(&sta
->plink_timer
);
677 sta
->plink_state
= PLINK_ESTAB
;
678 mesh_plink_inc_estab_count(sdata
);
679 spin_unlock_bh(&sta
->lock
);
680 mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
682 mesh_plink_frame_tx(sdata
, PLINK_CONFIRM
, sta
->sta
.addr
, llid
,
686 spin_unlock_bh(&sta
->lock
);
694 reason
= cpu_to_le16(MESH_CLOSE_RCVD
);
695 sta
->reason
= reason
;
696 __mesh_plink_deactivate(sta
);
697 sta
->plink_state
= PLINK_HOLDING
;
699 mod_plink_timer(sta
, dot11MeshHoldingTimeout(sdata
));
700 spin_unlock_bh(&sta
->lock
);
701 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
, llid
,
706 spin_unlock_bh(&sta
->lock
);
707 mesh_plink_frame_tx(sdata
, PLINK_CONFIRM
, sta
->sta
.addr
, llid
,
711 spin_unlock_bh(&sta
->lock
);
718 if (del_timer(&sta
->plink_timer
))
719 sta
->ignore_plink_timer
= 1;
720 mesh_plink_fsm_restart(sta
);
721 spin_unlock_bh(&sta
->lock
);
728 reason
= sta
->reason
;
729 spin_unlock_bh(&sta
->lock
);
730 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
,
734 spin_unlock_bh(&sta
->lock
);
738 /* should not get here, PLINK_BLOCKED is dealt with at the
739 * beggining of the function
741 spin_unlock_bh(&sta
->lock
);