2 * Copyright (c) 2008, 2009 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.
10 #include <linux/kernel.h>
11 #include <linux/random.h>
12 #include "ieee80211_i.h"
16 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
17 #define mpl_dbg(fmt, args...) printk(KERN_DEBUG fmt, ##args)
19 #define mpl_dbg(fmt, args...) do { (void)(0); } while (0)
22 #define PLINK_GET_LLID(p) (p + 4)
23 #define PLINK_GET_PLID(p) (p + 6)
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: mesh 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
, u32 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_KERNEL
);
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 bool __mesh_plink_deactivate(struct sta_info
*sta
)
126 struct ieee80211_sub_if_data
*sdata
= sta
->sdata
;
127 bool deactivated
= false;
129 if (sta
->plink_state
== PLINK_ESTAB
) {
130 mesh_plink_dec_estab_count(sdata
);
133 sta
->plink_state
= PLINK_BLOCKED
;
134 mesh_path_flush_by_nexthop(sta
);
140 * mesh_plink_deactivate - deactivate mesh peer link
142 * @sta: mesh peer link to deactivate
144 * All mesh paths with this peer as next hop will be flushed
146 void mesh_plink_deactivate(struct sta_info
*sta
)
148 struct ieee80211_sub_if_data
*sdata
= sta
->sdata
;
151 spin_lock_bh(&sta
->lock
);
152 deactivated
= __mesh_plink_deactivate(sta
);
153 spin_unlock_bh(&sta
->lock
);
156 ieee80211_bss_info_change_notify(sdata
, BSS_CHANGED_BEACON
);
159 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data
*sdata
,
160 enum plink_frame_type action
, u8
*da
, __le16 llid
, __le16 plid
,
162 struct ieee80211_local
*local
= sdata
->local
;
163 struct sk_buff
*skb
= dev_alloc_skb(local
->hw
.extra_tx_headroom
+ 400);
164 struct ieee80211_mgmt
*mgmt
;
165 bool include_plid
= false;
166 static const u8 meshpeeringproto
[] = { 0x00, 0x0F, 0xAC, 0x2A };
172 skb_reserve(skb
, local
->hw
.extra_tx_headroom
);
173 /* 25 is the size of the common mgmt part (24) plus the size of the
174 * common action part (1)
176 mgmt
= (struct ieee80211_mgmt
*)
177 skb_put(skb
, 25 + sizeof(mgmt
->u
.action
.u
.plink_action
));
178 memset(mgmt
, 0, 25 + sizeof(mgmt
->u
.action
.u
.plink_action
));
179 mgmt
->frame_control
= cpu_to_le16(IEEE80211_FTYPE_MGMT
|
180 IEEE80211_STYPE_ACTION
);
181 memcpy(mgmt
->da
, da
, ETH_ALEN
);
182 memcpy(mgmt
->sa
, sdata
->vif
.addr
, ETH_ALEN
);
183 /* BSSID is left zeroed, wildcard value */
184 mgmt
->u
.action
.category
= WLAN_CATEGORY_MESH_PLINK
;
185 mgmt
->u
.action
.u
.plink_action
.action_code
= action
;
187 if (action
== PLINK_CLOSE
)
188 mgmt
->u
.action
.u
.plink_action
.aux
= reason
;
190 mgmt
->u
.action
.u
.plink_action
.aux
= cpu_to_le16(0x0);
191 if (action
== PLINK_CONFIRM
) {
192 pos
= skb_put(skb
, 4);
193 /* two-byte status code followed by two-byte AID */
195 memcpy(pos
+ 2, &plid
, 2);
197 mesh_mgmt_ies_add(skb
, sdata
);
200 /* Add Peer Link Management element */
220 pos
= skb_put(skb
, 2 + ie_len
);
221 *pos
++ = WLAN_EID_PEER_LINK
;
223 memcpy(pos
, meshpeeringproto
, sizeof(meshpeeringproto
));
225 memcpy(pos
, &llid
, 2);
228 memcpy(pos
, &plid
, 2);
230 if (action
== PLINK_CLOSE
) {
232 memcpy(pos
, &reason
, 2);
235 ieee80211_tx_skb(sdata
, skb
);
239 void mesh_neighbour_update(u8
*hw_addr
, u32 rates
, struct ieee80211_sub_if_data
*sdata
,
240 bool peer_accepting_plinks
)
242 struct ieee80211_local
*local
= sdata
->local
;
243 struct sta_info
*sta
;
247 sta
= sta_info_get(sdata
, hw_addr
);
251 sta
= mesh_plink_alloc(sdata
, hw_addr
, rates
);
254 if (sta_info_insert_rcu(sta
)) {
260 sta
->last_rx
= jiffies
;
261 sta
->sta
.supp_rates
[local
->hw
.conf
.channel
->band
] = rates
;
262 if (peer_accepting_plinks
&& sta
->plink_state
== PLINK_LISTEN
&&
263 sdata
->u
.mesh
.accepting_plinks
&&
264 sdata
->u
.mesh
.mshcfg
.auto_open_plinks
)
265 mesh_plink_open(sta
);
270 static void mesh_plink_timer(unsigned long data
)
272 struct sta_info
*sta
;
273 __le16 llid
, plid
, reason
;
274 struct ieee80211_sub_if_data
*sdata
;
277 * This STA is valid because sta_info_destroy() will
278 * del_timer_sync() this timer after having made sure
279 * it cannot be readded (by deleting the plink.)
281 sta
= (struct sta_info
*) data
;
283 if (sta
->sdata
->local
->quiescing
) {
284 sta
->plink_timer_was_running
= true;
288 spin_lock_bh(&sta
->lock
);
289 if (sta
->ignore_plink_timer
) {
290 sta
->ignore_plink_timer
= false;
291 spin_unlock_bh(&sta
->lock
);
294 mpl_dbg("Mesh plink timer for %pM fired on state %d\n",
295 sta
->sta
.addr
, sta
->plink_state
);
301 switch (sta
->plink_state
) {
305 if (sta
->plink_retries
< dot11MeshMaxRetries(sdata
)) {
307 mpl_dbg("Mesh plink for %pM (retry, timeout): %d %d\n",
308 sta
->sta
.addr
, sta
->plink_retries
,
310 get_random_bytes(&rand
, sizeof(u32
));
311 sta
->plink_timeout
= sta
->plink_timeout
+
312 rand
% sta
->plink_timeout
;
313 ++sta
->plink_retries
;
314 mod_plink_timer(sta
, sta
->plink_timeout
);
315 spin_unlock_bh(&sta
->lock
);
316 mesh_plink_frame_tx(sdata
, PLINK_OPEN
, sta
->sta
.addr
, llid
,
320 reason
= cpu_to_le16(MESH_MAX_RETRIES
);
321 /* fall through on else */
325 reason
= cpu_to_le16(MESH_CONFIRM_TIMEOUT
);
326 sta
->plink_state
= PLINK_HOLDING
;
327 mod_plink_timer(sta
, dot11MeshHoldingTimeout(sdata
));
328 spin_unlock_bh(&sta
->lock
);
329 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
, llid
, plid
,
334 del_timer(&sta
->plink_timer
);
335 mesh_plink_fsm_restart(sta
);
336 spin_unlock_bh(&sta
->lock
);
339 spin_unlock_bh(&sta
->lock
);
345 void mesh_plink_quiesce(struct sta_info
*sta
)
347 if (del_timer_sync(&sta
->plink_timer
))
348 sta
->plink_timer_was_running
= true;
351 void mesh_plink_restart(struct sta_info
*sta
)
353 if (sta
->plink_timer_was_running
) {
354 add_timer(&sta
->plink_timer
);
355 sta
->plink_timer_was_running
= false;
360 static inline void mesh_plink_timer_set(struct sta_info
*sta
, int timeout
)
362 sta
->plink_timer
.expires
= jiffies
+ (HZ
* timeout
/ 1000);
363 sta
->plink_timer
.data
= (unsigned long) sta
;
364 sta
->plink_timer
.function
= mesh_plink_timer
;
365 sta
->plink_timeout
= timeout
;
366 add_timer(&sta
->plink_timer
);
369 int mesh_plink_open(struct sta_info
*sta
)
372 struct ieee80211_sub_if_data
*sdata
= sta
->sdata
;
374 spin_lock_bh(&sta
->lock
);
375 get_random_bytes(&llid
, 2);
377 if (sta
->plink_state
!= PLINK_LISTEN
) {
378 spin_unlock_bh(&sta
->lock
);
381 sta
->plink_state
= PLINK_OPN_SNT
;
382 mesh_plink_timer_set(sta
, dot11MeshRetryTimeout(sdata
));
383 spin_unlock_bh(&sta
->lock
);
384 mpl_dbg("Mesh plink: starting establishment with %pM\n",
387 return mesh_plink_frame_tx(sdata
, PLINK_OPEN
,
388 sta
->sta
.addr
, llid
, 0, 0);
391 void mesh_plink_block(struct sta_info
*sta
)
393 struct ieee80211_sub_if_data
*sdata
= sta
->sdata
;
396 spin_lock_bh(&sta
->lock
);
397 deactivated
= __mesh_plink_deactivate(sta
);
398 sta
->plink_state
= PLINK_BLOCKED
;
399 spin_unlock_bh(&sta
->lock
);
402 ieee80211_bss_info_change_notify(sdata
, BSS_CHANGED_BEACON
);
406 void mesh_rx_plink_frame(struct ieee80211_sub_if_data
*sdata
, struct ieee80211_mgmt
*mgmt
,
407 size_t len
, struct ieee80211_rx_status
*rx_status
)
409 struct ieee80211_local
*local
= sdata
->local
;
410 struct ieee802_11_elems elems
;
411 struct sta_info
*sta
;
412 enum plink_event event
;
413 enum plink_frame_type ftype
;
415 bool deactivated
, matches_local
= true;
418 __le16 plid
, llid
, reason
;
419 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
420 static const char *mplstates
[] = {
421 [PLINK_LISTEN
] = "LISTEN",
422 [PLINK_OPN_SNT
] = "OPN-SNT",
423 [PLINK_OPN_RCVD
] = "OPN-RCVD",
424 [PLINK_CNF_RCVD
] = "CNF_RCVD",
425 [PLINK_ESTAB
] = "ESTAB",
426 [PLINK_HOLDING
] = "HOLDING",
427 [PLINK_BLOCKED
] = "BLOCKED"
431 /* need action_code, aux */
432 if (len
< IEEE80211_MIN_ACTION_SIZE
+ 3)
435 if (is_multicast_ether_addr(mgmt
->da
)) {
436 mpl_dbg("Mesh plink: ignore frame from multicast address");
440 baseaddr
= mgmt
->u
.action
.u
.plink_action
.variable
;
441 baselen
= (u8
*) mgmt
->u
.action
.u
.plink_action
.variable
- (u8
*) mgmt
;
442 if (mgmt
->u
.action
.u
.plink_action
.action_code
== PLINK_CONFIRM
) {
446 ieee802_11_parse_elems(baseaddr
, len
- baselen
, &elems
);
447 if (!elems
.peer_link
) {
448 mpl_dbg("Mesh plink: missing necessary peer link ie\n");
452 ftype
= mgmt
->u
.action
.u
.plink_action
.action_code
;
453 ie_len
= elems
.peer_link_len
;
454 if ((ftype
== PLINK_OPEN
&& ie_len
!= 6) ||
455 (ftype
== PLINK_CONFIRM
&& ie_len
!= 8) ||
456 (ftype
== PLINK_CLOSE
&& ie_len
!= 8 && ie_len
!= 10)) {
457 mpl_dbg("Mesh plink: incorrect plink ie length %d %d\n",
462 if (ftype
!= PLINK_CLOSE
&& (!elems
.mesh_id
|| !elems
.mesh_config
)) {
463 mpl_dbg("Mesh plink: missing necessary ie\n");
466 /* Note the lines below are correct, the llid in the frame is the plid
467 * from the point of view of this host.
469 memcpy(&plid
, PLINK_GET_LLID(elems
.peer_link
), 2);
470 if (ftype
== PLINK_CONFIRM
|| (ftype
== PLINK_CLOSE
&& ie_len
== 10))
471 memcpy(&llid
, PLINK_GET_PLID(elems
.peer_link
), 2);
475 sta
= sta_info_get(sdata
, mgmt
->sa
);
476 if (!sta
&& ftype
!= PLINK_OPEN
) {
477 mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
482 if (sta
&& sta
->plink_state
== PLINK_BLOCKED
) {
487 /* Now we will figure out the appropriate event... */
488 event
= PLINK_UNDEFINED
;
489 if (ftype
!= PLINK_CLOSE
&& (!mesh_matches_local(&elems
, sdata
))) {
490 matches_local
= false;
504 if (!sta
&& !matches_local
) {
506 reason
= cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION
);
508 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, mgmt
->sa
, llid
,
512 /* ftype == PLINK_OPEN */
517 if (!mesh_plink_free_count(sdata
)) {
518 mpl_dbg("Mesh plink error: no more free plinks\n");
522 rates
= ieee80211_sta_get_rates(local
, &elems
, rx_status
->band
);
523 sta
= mesh_plink_alloc(sdata
, mgmt
->sa
, rates
);
525 mpl_dbg("Mesh plink error: plink table full\n");
528 if (sta_info_insert_rcu(sta
)) {
533 spin_lock_bh(&sta
->lock
);
534 } else if (matches_local
) {
535 spin_lock_bh(&sta
->lock
);
538 if (!mesh_plink_free_count(sdata
) ||
539 (sta
->plid
&& sta
->plid
!= plid
))
545 if (!mesh_plink_free_count(sdata
) ||
546 (sta
->llid
!= llid
|| sta
->plid
!= plid
))
552 if (sta
->plink_state
== PLINK_ESTAB
)
553 /* Do not check for llid or plid. This does not
554 * follow the standard but since multiple plinks
555 * per sta are not supported, it is necessary in
556 * order to avoid a livelock when MP A sees an
557 * establish peer link to MP B but MP B does not
558 * see it. This can be caused by a timeout in
559 * B's peer link establishment or B beign
563 else if (sta
->plid
!= plid
)
565 else if (ie_len
== 7 && sta
->llid
!= llid
)
571 mpl_dbg("Mesh plink: unknown frame subtype\n");
572 spin_unlock_bh(&sta
->lock
);
577 spin_lock_bh(&sta
->lock
);
580 mpl_dbg("Mesh plink (peer, state, llid, plid, event): %pM %s %d %d %d\n",
581 mgmt
->sa
, mplstates
[sta
->plink_state
],
582 le16_to_cpu(sta
->llid
), le16_to_cpu(sta
->plid
),
585 switch (sta
->plink_state
) {
586 /* spin_unlock as soon as state is updated at each case */
590 mesh_plink_fsm_restart(sta
);
591 spin_unlock_bh(&sta
->lock
);
594 sta
->plink_state
= PLINK_OPN_RCVD
;
596 get_random_bytes(&llid
, 2);
598 mesh_plink_timer_set(sta
, dot11MeshRetryTimeout(sdata
));
599 spin_unlock_bh(&sta
->lock
);
600 mesh_plink_frame_tx(sdata
, PLINK_OPEN
, sta
->sta
.addr
, llid
,
602 mesh_plink_frame_tx(sdata
, PLINK_CONFIRM
, sta
->sta
.addr
,
606 spin_unlock_bh(&sta
->lock
);
615 reason
= cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION
);
618 reason
= cpu_to_le16(MESH_CLOSE_RCVD
);
619 sta
->reason
= reason
;
620 sta
->plink_state
= PLINK_HOLDING
;
621 if (!mod_plink_timer(sta
,
622 dot11MeshHoldingTimeout(sdata
)))
623 sta
->ignore_plink_timer
= true;
626 spin_unlock_bh(&sta
->lock
);
627 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
, llid
,
631 /* retry timer is left untouched */
632 sta
->plink_state
= PLINK_OPN_RCVD
;
635 spin_unlock_bh(&sta
->lock
);
636 mesh_plink_frame_tx(sdata
, PLINK_CONFIRM
, sta
->sta
.addr
, llid
,
640 sta
->plink_state
= PLINK_CNF_RCVD
;
641 if (!mod_plink_timer(sta
,
642 dot11MeshConfirmTimeout(sdata
)))
643 sta
->ignore_plink_timer
= true;
645 spin_unlock_bh(&sta
->lock
);
648 spin_unlock_bh(&sta
->lock
);
657 reason
= cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION
);
660 reason
= cpu_to_le16(MESH_CLOSE_RCVD
);
661 sta
->reason
= reason
;
662 sta
->plink_state
= PLINK_HOLDING
;
663 if (!mod_plink_timer(sta
,
664 dot11MeshHoldingTimeout(sdata
)))
665 sta
->ignore_plink_timer
= true;
668 spin_unlock_bh(&sta
->lock
);
669 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
, llid
,
674 spin_unlock_bh(&sta
->lock
);
675 mesh_plink_frame_tx(sdata
, PLINK_CONFIRM
, sta
->sta
.addr
, llid
,
679 del_timer(&sta
->plink_timer
);
680 sta
->plink_state
= PLINK_ESTAB
;
681 spin_unlock_bh(&sta
->lock
);
682 mesh_plink_inc_estab_count(sdata
);
683 ieee80211_bss_info_change_notify(sdata
, BSS_CHANGED_BEACON
);
684 mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
688 spin_unlock_bh(&sta
->lock
);
697 reason
= cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION
);
700 reason
= cpu_to_le16(MESH_CLOSE_RCVD
);
701 sta
->reason
= reason
;
702 sta
->plink_state
= PLINK_HOLDING
;
703 if (!mod_plink_timer(sta
,
704 dot11MeshHoldingTimeout(sdata
)))
705 sta
->ignore_plink_timer
= true;
708 spin_unlock_bh(&sta
->lock
);
709 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
, llid
,
713 del_timer(&sta
->plink_timer
);
714 sta
->plink_state
= PLINK_ESTAB
;
715 spin_unlock_bh(&sta
->lock
);
716 mesh_plink_inc_estab_count(sdata
);
717 ieee80211_bss_info_change_notify(sdata
, BSS_CHANGED_BEACON
);
718 mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
720 mesh_plink_frame_tx(sdata
, PLINK_CONFIRM
, sta
->sta
.addr
, llid
,
724 spin_unlock_bh(&sta
->lock
);
732 reason
= cpu_to_le16(MESH_CLOSE_RCVD
);
733 sta
->reason
= reason
;
734 deactivated
= __mesh_plink_deactivate(sta
);
735 sta
->plink_state
= PLINK_HOLDING
;
737 mod_plink_timer(sta
, dot11MeshHoldingTimeout(sdata
));
738 spin_unlock_bh(&sta
->lock
);
740 ieee80211_bss_info_change_notify(sdata
, BSS_CHANGED_BEACON
);
741 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
, llid
,
746 spin_unlock_bh(&sta
->lock
);
747 mesh_plink_frame_tx(sdata
, PLINK_CONFIRM
, sta
->sta
.addr
, llid
,
751 spin_unlock_bh(&sta
->lock
);
758 if (del_timer(&sta
->plink_timer
))
759 sta
->ignore_plink_timer
= 1;
760 mesh_plink_fsm_restart(sta
);
761 spin_unlock_bh(&sta
->lock
);
768 reason
= sta
->reason
;
769 spin_unlock_bh(&sta
->lock
);
770 mesh_plink_frame_tx(sdata
, PLINK_CLOSE
, sta
->sta
.addr
,
774 spin_unlock_bh(&sta
->lock
);
778 /* should not get here, PLINK_BLOCKED is dealt with at the
779 * beginning of the function
781 spin_unlock_bh(&sta
->lock
);