1/*
2 * Copyright (c) 2008, 2009 open80211s Ltd.
3 * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
4 *             Javier Cardona <javier@cozybit.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#ifndef IEEE80211S_H
12#define IEEE80211S_H
13
14#include <linux/types.h>
15#include <linux/jhash.h>
16#include "ieee80211_i.h"
17
18
19/* Data structures */
20
21/**
22 * enum mesh_path_flags - mac80211 mesh path flags
23 *
24 *
25 *
26 * @MESH_PATH_ACTIVE: the mesh path can be used for forwarding
27 * @MESH_PATH_RESOLVING: the discovery process is running for this mesh path
28 * @MESH_PATH_SN_VALID: the mesh path contains a valid destination sequence
29 *	number
30 * @MESH_PATH_FIXED: the mesh path has been manually set and should not be
31 *	modified
32 * @MESH_PATH_RESOLVED: the mesh path can has been resolved
33 * @MESH_PATH_REQ_QUEUED: there is an unsent path request for this destination
34 *	already queued up, waiting for the discovery process to start.
35 *
36 * MESH_PATH_RESOLVED is used by the mesh path timer to
37 * decide when to stop or cancel the mesh path discovery.
38 */
39enum mesh_path_flags {
40	MESH_PATH_ACTIVE =	BIT(0),
41	MESH_PATH_RESOLVING =	BIT(1),
42	MESH_PATH_SN_VALID =	BIT(2),
43	MESH_PATH_FIXED	=	BIT(3),
44	MESH_PATH_RESOLVED =	BIT(4),
45	MESH_PATH_REQ_QUEUED =	BIT(5),
46};
47
48/**
49 * enum mesh_deferred_task_flags - mac80211 mesh deferred tasks
50 *
51 *
52 *
53 * @MESH_WORK_HOUSEKEEPING: run the periodic mesh housekeeping tasks
54 * @MESH_WORK_GROW_MPATH_TABLE: the mesh path table is full and needs
55 * to grow.
56 * @MESH_WORK_GROW_MPP_TABLE: the mesh portals table is full and needs to
57 * grow
58 * @MESH_WORK_ROOT: the mesh root station needs to send a frame
59 * @MESH_WORK_DRIFT_ADJUST: time to compensate for clock drift relative to other
60 * mesh nodes
61 * @MESH_WORK_MBSS_CHANGED: rebuild beacon and notify driver of BSS changes
62 */
63enum mesh_deferred_task_flags {
64	MESH_WORK_HOUSEKEEPING,
65	MESH_WORK_GROW_MPATH_TABLE,
66	MESH_WORK_GROW_MPP_TABLE,
67	MESH_WORK_ROOT,
68	MESH_WORK_DRIFT_ADJUST,
69	MESH_WORK_MBSS_CHANGED,
70};
71
72/**
73 * struct mesh_path - mac80211 mesh path structure
74 *
75 * @dst: mesh path destination mac address
76 * @sdata: mesh subif
77 * @next_hop: mesh neighbor to which frames for this destination will be
78 *	forwarded
79 * @timer: mesh path discovery timer
80 * @frame_queue: pending queue for frames sent to this destination while the
81 *	path is unresolved
82 * @sn: target sequence number
83 * @metric: current metric to this destination
84 * @hop_count: hops to destination
85 * @exp_time: in jiffies, when the path will expire or when it expired
86 * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery
87 *	retry
88 * @discovery_retries: number of discovery retries
89 * @flags: mesh path flags, as specified on &enum mesh_path_flags
90 * @state_lock: mesh path state lock used to protect changes to the
91 * mpath itself.  No need to take this lock when adding or removing
92 * an mpath to a hash bucket on a path table.
93 * @rann_snd_addr: the RANN sender address
94 * @rann_metric: the aggregated path metric towards the root node
95 * @last_preq_to_root: Timestamp of last PREQ sent to root
96 * @is_root: the destination station of this path is a root node
97 * @is_gate: the destination station of this path is a mesh gate
98 *
99 *
100 * The combination of dst and sdata is unique in the mesh path table. Since the
101 * next_hop STA is only protected by RCU as well, deleting the STA must also
102 * remove/substitute the mesh_path structure and wait until that is no longer
103 * reachable before destroying the STA completely.
104 */
105struct mesh_path {
106	u8 dst[ETH_ALEN];
107	u8 mpp[ETH_ALEN];	/* used for MPP or MAP */
108	struct ieee80211_sub_if_data *sdata;
109	struct sta_info __rcu *next_hop;
110	struct timer_list timer;
111	struct sk_buff_head frame_queue;
112	struct rcu_head rcu;
113	u32 sn;
114	u32 metric;
115	u8 hop_count;
116	unsigned long exp_time;
117	u32 discovery_timeout;
118	u8 discovery_retries;
119	enum mesh_path_flags flags;
120	spinlock_t state_lock;
121	u8 rann_snd_addr[ETH_ALEN];
122	u32 rann_metric;
123	unsigned long last_preq_to_root;
124	bool is_root;
125	bool is_gate;
126};
127
128/**
129 * struct mesh_table
130 *
131 * @hash_buckets: array of hash buckets of the table
132 * @hashwlock: array of locks to protect write operations, one per bucket
133 * @hash_mask: 2^size_order - 1, used to compute hash idx
134 * @hash_rnd: random value used for hash computations
135 * @entries: number of entries in the table
136 * @free_node: function to free nodes of the table
137 * @copy_node: function to copy nodes of the table
138 * @size_order: determines size of the table, there will be 2^size_order hash
139 *	buckets
140 * @mean_chain_len: maximum average length for the hash buckets' list, if it is
141 *	reached, the table will grow
142 * @known_gates: list of known mesh gates and their mpaths by the station. The
143 * gate's mpath may or may not be resolved and active.
144 *
145 * rcu_head: RCU head to free the table
146 */
147struct mesh_table {
148	/* Number of buckets will be 2^N */
149	struct hlist_head *hash_buckets;
150	spinlock_t *hashwlock;		/* One per bucket, for add/del */
151	unsigned int hash_mask;		/* (2^size_order) - 1 */
152	__u32 hash_rnd;			/* Used for hash generation */
153	atomic_t entries;		/* Up to MAX_MESH_NEIGHBOURS */
154	void (*free_node) (struct hlist_node *p, bool free_leafs);
155	int (*copy_node) (struct hlist_node *p, struct mesh_table *newtbl);
156	int size_order;
157	int mean_chain_len;
158	struct hlist_head *known_gates;
159	spinlock_t gates_lock;
160
161	struct rcu_head rcu_head;
162};
163
164/* Recent multicast cache */
165/* RMC_BUCKETS must be a power of 2, maximum 256 */
166#define RMC_BUCKETS		256
167#define RMC_QUEUE_MAX_LEN	4
168#define RMC_TIMEOUT		(3 * HZ)
169
170/**
171 * struct rmc_entry - entry in the Recent Multicast Cache
172 *
173 * @seqnum: mesh sequence number of the frame
174 * @exp_time: expiration time of the entry, in jiffies
175 * @sa: source address of the frame
176 *
177 * The Recent Multicast Cache keeps track of the latest multicast frames that
178 * have been received by a mesh interface and discards received multicast frames
179 * that are found in the cache.
180 */
181struct rmc_entry {
182	struct list_head list;
183	u32 seqnum;
184	unsigned long exp_time;
185	u8 sa[ETH_ALEN];
186};
187
188struct mesh_rmc {
189	struct list_head bucket[RMC_BUCKETS];
190	u32 idx_mask;
191};
192
193#define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
194
195#define MESH_PATH_EXPIRE (600 * HZ)
196
197/* Default maximum number of plinks per interface */
198#define MESH_MAX_PLINKS		256
199
200/* Maximum number of paths per interface */
201#define MESH_MAX_MPATHS		1024
202
203/* Number of frames buffered per destination for unresolved destinations */
204#define MESH_FRAME_QUEUE_LEN	10
205
206/* Public interfaces */
207/* Various */
208int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
209				  const u8 *da, const u8 *sa);
210int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
211			      struct ieee80211s_hdr *meshhdr,
212			      const char *addr4or5, const char *addr6);
213int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
214		   const u8 *addr, struct ieee80211s_hdr *mesh_hdr);
215bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
216			struct ieee802_11_elems *ie);
217void mesh_ids_set_default(struct ieee80211_if_mesh *mesh);
218int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
219			 struct sk_buff *skb);
220int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata,
221		       struct sk_buff *skb);
222int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata,
223		    struct sk_buff *skb);
224int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
225			struct sk_buff *skb);
226int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
227		       struct sk_buff *skb);
228int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
229			struct sk_buff *skb);
230void mesh_rmc_free(struct ieee80211_sub_if_data *sdata);
231int mesh_rmc_init(struct ieee80211_sub_if_data *sdata);
232void ieee80211s_init(void);
233void ieee80211s_update_metric(struct ieee80211_local *local,
234			      struct sta_info *sta, struct sk_buff *skb);
235void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);
236int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata);
237void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata);
238void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh);
239const struct ieee80211_mesh_sync_ops *ieee80211_mesh_sync_ops_get(u8 method);
240/* wrapper for ieee80211_bss_info_change_notify() */
241void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
242				       u32 changed);
243
244/* mesh power save */
245u32 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata);
246u32 ieee80211_mps_set_sta_local_pm(struct sta_info *sta,
247				   enum nl80211_mesh_power_mode pm);
248void ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data *sdata,
249				   struct sta_info *sta,
250				   struct ieee80211_hdr *hdr);
251void ieee80211_mps_sta_status_update(struct sta_info *sta);
252void ieee80211_mps_rx_h_sta_process(struct sta_info *sta,
253				    struct ieee80211_hdr *hdr);
254void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
255				    bool tx, bool acked);
256void ieee80211_mps_frame_release(struct sta_info *sta,
257				 struct ieee802_11_elems *elems);
258
259/* Mesh paths */
260int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata,
261			struct sk_buff *skb);
262int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
263			 struct sk_buff *skb);
264void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata);
265struct mesh_path *mesh_path_lookup(struct ieee80211_sub_if_data *sdata,
266				   const u8 *dst);
267struct mesh_path *mpp_path_lookup(struct ieee80211_sub_if_data *sdata,
268				  const u8 *dst);
269int mpp_path_add(struct ieee80211_sub_if_data *sdata,
270		 const u8 *dst, const u8 *mpp);
271struct mesh_path *
272mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx);
273void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop);
274void mesh_path_expire(struct ieee80211_sub_if_data *sdata);
275void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
276			    struct ieee80211_mgmt *mgmt, size_t len);
277struct mesh_path *
278mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst);
279
280int mesh_path_add_gate(struct mesh_path *mpath);
281int mesh_path_send_to_gates(struct mesh_path *mpath);
282int mesh_gate_num(struct ieee80211_sub_if_data *sdata);
283
284/* Mesh plinks */
285void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
286			   u8 *hw_addr, struct ieee802_11_elems *ie);
287bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
288u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
289void mesh_plink_broken(struct sta_info *sta);
290u32 mesh_plink_deactivate(struct sta_info *sta);
291u32 mesh_plink_open(struct sta_info *sta);
292u32 mesh_plink_block(struct sta_info *sta);
293void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
294			 struct ieee80211_mgmt *mgmt, size_t len,
295			 struct ieee80211_rx_status *rx_status);
296void mesh_sta_cleanup(struct sta_info *sta);
297
298/* Private interfaces */
299/* Mesh tables */
300void mesh_mpath_table_grow(void);
301void mesh_mpp_table_grow(void);
302/* Mesh paths */
303int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata,
304		       u8 ttl, const u8 *target, u32 target_sn,
305		       u16 target_rcode, const u8 *ra);
306void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta);
307void mesh_path_flush_pending(struct mesh_path *mpath);
308void mesh_path_tx_pending(struct mesh_path *mpath);
309int mesh_pathtbl_init(void);
310void mesh_pathtbl_unregister(void);
311int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr);
312void mesh_path_timer(unsigned long data);
313void mesh_path_flush_by_nexthop(struct sta_info *sta);
314void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
315			     struct sk_buff *skb);
316void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata);
317
318bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt);
319extern int mesh_paths_generation;
320
321#ifdef CONFIG_MAC80211_MESH
322static inline
323u32 mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
324{
325	atomic_inc(&sdata->u.mesh.estab_plinks);
326	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
327}
328
329static inline
330u32 mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
331{
332	atomic_dec(&sdata->u.mesh.estab_plinks);
333	return mesh_accept_plinks_update(sdata) | BSS_CHANGED_BEACON;
334}
335
336static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
337{
338	return sdata->u.mesh.mshcfg.dot11MeshMaxPeerLinks -
339	       atomic_read(&sdata->u.mesh.estab_plinks);
340}
341
342static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
343{
344	return (min_t(long, mesh_plink_free_count(sdata),
345		   MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
346}
347
348static inline void mesh_path_activate(struct mesh_path *mpath)
349{
350	mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED;
351}
352
353static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
354{
355	return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP;
356}
357
358void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local);
359
360void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata);
361void mesh_sync_adjust_tbtt(struct ieee80211_sub_if_data *sdata);
362void ieee80211s_stop(void);
363#else
364static inline void
365ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local) {}
366static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
367{ return false; }
368static inline void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
369{}
370static inline void ieee80211s_stop(void) {}
371#endif
372
373#endif /* IEEE80211S_H */
374