[deliverable/linux.git] / net / mac80211 / mesh.h

/*
 * Copyright (c) 2008 open80211s Ltd.
 * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
 *             Javier Cardona <javier@cozybit.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef IEEE80211S_H
#define IEEE80211S_H

#include <linux/types.h>
#include <linux/jhash.h>
#include "ieee80211_i.h"


/* Data structures */

/**
 * enum mesh_path_flags - mac80211 mesh path flags
 *
 *
 *
 * @MESH_PATH_ACTIVE: the mesh path is can be used for forwarding
 * @MESH_PATH_RESOLVED: the discovery process is running for this mesh path
 * @MESH_PATH_DSN_VALID: the mesh path contains a valid destination sequence
 * 	number
 * @MESH_PATH_FIXED: the mesh path has been manually set and should not be
 * 	modified
 * @MESH_PATH_RESOLVED: the mesh path can has been resolved
 * @MESH_PATH_DELETE: the mesh path is scheduled to be deleted
 *
 * MESH_PATH_RESOLVED and MESH_PATH_DELETE are used by the mesh path timer to
 * decide when to stop or cancel the mesh path discovery.
 */
enum mesh_path_flags {
	MESH_PATH_ACTIVE =	BIT(0),
	MESH_PATH_RESOLVING =	BIT(1),
	MESH_PATH_DSN_VALID =	BIT(2),
	MESH_PATH_FIXED	=	BIT(3),
	MESH_PATH_RESOLVED =	BIT(4),
	MESH_PATH_DELETE =	BIT(5),
};

/**
 * struct mesh_path - mac80211 mesh path structure
 *
 * @dst: mesh path destination mac address
 * @dev: mesh path device
 * @next_hop: mesh neighbor to which frames for this destination will be
 * 	forwarded
 * @timer: mesh path discovery timer
 * @frame_queue: pending queue for frames sent to this destination while the
 * 	path is unresolved
 * @dsn: destination sequence number of the destination
 * @metric: current metric to this destination
 * @hop_count: hops to destination
 * @exp_time: in jiffies, when the path will expire or when it expired
 * @discovery_timeout: timeout (lapse in jiffies) used for the last discovery
 * 	retry
 * @discovery_retries: number of discovery retries
 * @flags: mesh path flags, as specified on &enum mesh_path_flags
 * @state_lock: mesh pat state lock
 *
 *
 * The combination of dst and dev is unique in the mesh path table. A reference
 * to the next_hop sta will be kept and in case this sta is removed, the
 * mesh_path structure must be also removed or substitued in a rcu safe way
 */
struct mesh_path {
	u8 dst[ETH_ALEN];
	struct net_device *dev;
	struct sta_info *next_hop;
	struct timer_list timer;
	struct sk_buff_head frame_queue;
	struct rcu_head rcu;
	u32 dsn;
	u32 metric;
	u8 hop_count;
	unsigned long exp_time;
	u32 discovery_timeout;
	u8 discovery_retries;
	enum mesh_path_flags flags;
	spinlock_t state_lock;
};

/**
 * struct mesh_table
 *
 * @hash_buckets: array of hash buckets of the table
 * @hashwlock: array of locks to protect write operations, one per bucket
 * @hash_mask: 2^size_order - 1, used to compute hash idx
 * @hash_rnd: random value used for hash computations
 * @entries: number of entries in the table
 * @free_node: function to free nodes of the table
 * @copy_node: fuction to copy nodes of the table
 * @size_order: determines size of the table, there will be 2^size_order hash
 *	buckets
 * @mean_chain_len: maximum average length for the hash buckets' list, if it is
 *	reached, the table will grow
 */
struct mesh_table {
	/* Number of buckets will be 2^N */
	struct hlist_head *hash_buckets;
	spinlock_t *hashwlock;		/* One per bucket, for add/del */
	unsigned int hash_mask;		/* (2^size_order) - 1 */
	__u32 hash_rnd;			/* Used for hash generation */
	atomic_t entries;		/* Up to MAX_MESH_NEIGHBOURS */
	void (*free_node) (struct hlist_node *p, bool free_leafs);
	void (*copy_node) (struct hlist_node *p, struct mesh_table *newtbl);
	int size_order;
	int mean_chain_len;
};

/* Recent multicast cache */
/* RMC_BUCKETS must be a power of 2, maximum 256 */
#define RMC_BUCKETS		256
#define RMC_QUEUE_MAX_LEN	4
#define RMC_TIMEOUT		(3 * HZ)

/**
 * struct rmc_entry - entry in the Recent Multicast Cache
 *
 * @seqnum: mesh sequence number of the frame
 * @exp_time: expiration time of the entry, in jiffies
 * @sa: source address of the frame
 *
 * The Recent Multicast Cache keeps track of the latest multicast frames that
 * have been received by a mesh interface and discards received multicast frames
 * that are found in the cache.
 */
struct rmc_entry {
	struct list_head list;
	u32 seqnum;
	unsigned long exp_time;
	u8 sa[ETH_ALEN];
};

struct mesh_rmc {
	struct rmc_entry bucket[RMC_BUCKETS];
	u8 idx_mask;
};


/* Mesh IEs constants */
#define MESH_CFG_LEN		19

/*
 * MESH_CFG_COMP_LEN Includes:
 * 	- Active path selection protocol ID.
 * 	- Active path selection metric ID.
 * 	- Congestion control mode identifier.
 * 	- Channel precedence.
 * Does not include mesh capabilities, which may vary across nodes in the same
 * mesh
 */
#define MESH_CFG_CMP_LEN 	17

/* Default values, timeouts in ms */
#define MESH_TTL 		5
#define MESH_MAX_RETR	 	3
#define MESH_RET_T 		100
#define MESH_CONF_T 		100
#define MESH_HOLD_T 		100

#define MESH_PATH_TIMEOUT	5000
/* Minimum interval between two consecutive PREQs originated by the same
 * interface
 */
#define MESH_PREQ_MIN_INT	10
#define MESH_DIAM_TRAVERSAL_TIME 50
/* Paths will be refreshed if they are closer than PATH_REFRESH_TIME to their
 * expiration
 */
#define MESH_PATH_REFRESH_TIME			1000
#define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME)

#define MESH_MAX_PREQ_RETRIES 4
#define MESH_PATH_EXPIRE (600 * HZ)

/* Default maximum number of established plinks per interface */
#define MESH_MAX_ESTAB_PLINKS	32

/* Default maximum number of plinks per interface */
#define MESH_MAX_PLINKS		256

/* Maximum number of paths per interface */
#define MESH_MAX_MPATHS		1024

/* Pending ANA approval */
#define PLINK_CATEGORY		30
#define MESH_PATH_SEL_CATEGORY	32

/* Mesh Header Flags */
#define IEEE80211S_FLAGS_AE	0x3

/* Public interfaces */
/* Various */
u8 mesh_id_hash(u8 *mesh_id, int mesh_id_len);
int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr);
int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
		struct ieee80211_sub_if_data *sdata);
int mesh_rmc_check(u8 *addr, struct ieee80211s_hdr *mesh_hdr,
		struct net_device *dev);
bool mesh_matches_local(struct ieee802_11_elems *ie, struct net_device *dev);
void mesh_ids_set_default(struct ieee80211_if_sta *sta);
void mesh_mgmt_ies_add(struct sk_buff *skb, struct net_device *dev);
void mesh_rmc_free(struct net_device *dev);
int mesh_rmc_init(struct net_device *dev);
void ieee80211s_init(void);
void ieee80211s_stop(void);
void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);

/* Mesh paths */
int mesh_nexthop_lookup(u8 *next_hop, struct sk_buff *skb,
		struct net_device *dev);
void mesh_path_start_discovery(struct net_device *dev);
struct mesh_path *mesh_path_lookup(u8 *dst, struct net_device *dev);
struct mesh_path *mesh_path_lookup_by_idx(int idx, struct net_device *dev);
void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop);
void mesh_path_expire(struct net_device *dev);
void mesh_path_flush(struct net_device *dev);
void mesh_rx_path_sel_frame(struct net_device *dev, struct ieee80211_mgmt *mgmt,
		size_t len);
int mesh_path_add(u8 *dst, struct net_device *dev);
/* Mesh plinks */
void mesh_neighbour_update(u8 *hw_addr, u64 rates, struct net_device *dev,
		bool add);
bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie,
			      struct net_device *dev);
void mesh_accept_plinks_update(struct net_device *dev);
struct sta_info *mesh_plink_add(u8 *hw_addr, u64 rates, struct net_device *dev);
void mesh_plink_broken(struct sta_info *sta);
void mesh_plink_deactivate(struct sta_info *sta);
int mesh_plink_open(struct sta_info *sta);
int mesh_plink_close(struct sta_info *sta);
void mesh_plink_block(struct sta_info *sta);
void mesh_rx_plink_frame(struct net_device *dev, struct ieee80211_mgmt *mgmt,
			 size_t len, struct ieee80211_rx_status *rx_status);

/* Private interfaces */
/* Mesh tables */
struct mesh_table *mesh_table_alloc(int size_order);
void mesh_table_free(struct mesh_table *tbl, bool free_leafs);
struct mesh_table *mesh_table_grow(struct mesh_table *tbl);
u32 mesh_table_hash(u8 *addr, struct net_device *dev, struct mesh_table *tbl);
/* Mesh paths */
int mesh_path_error_tx(u8 *dest, __le32 dest_dsn, u8 *ra,
		struct net_device *dev);
void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta);
void mesh_path_flush_pending(struct mesh_path *mpath);
void mesh_path_tx_pending(struct mesh_path *mpath);
int mesh_pathtbl_init(void);
void mesh_pathtbl_unregister(void);
int mesh_path_del(u8 *addr, struct net_device *dev);
void mesh_path_timer(unsigned long data);
void mesh_path_flush_by_nexthop(struct sta_info *sta);
void mesh_path_discard_frame(struct sk_buff *skb, struct net_device *dev);

#ifdef CONFIG_MAC80211_MESH
extern int mesh_allocated;

static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
{
	return sdata->u.sta.mshcfg.dot11MeshMaxPeerLinks -
	       atomic_read(&sdata->u.sta.mshstats.estab_plinks);
}

static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
{
	return (min(mesh_plink_free_count(sdata),
		   MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
}

static inline void mesh_path_activate(struct mesh_path *mpath)
{
	mpath->flags |= MESH_PATH_ACTIVE | MESH_PATH_RESOLVED;
}

#define for_each_mesh_entry(x, p, node, i) \
	for (i = 0; i <= x->hash_mask; i++) \
		hlist_for_each_entry_rcu(node, p, &x->hash_buckets[i], list)

#else
#define mesh_allocated	0
#endif

#define MESH_PREQ(skb)	(skb->cb + 30)

#endif /* IEEE80211S_H */
Commit	Line	Data
ccf80ddf LCC	1	/*
	2	* Copyright (c) 2008 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
902acc78	14	#include <linux/types.h>
ccf80ddf	15	#include <linux/jhash.h>
902acc78	16	#include "ieee80211_i.h"
ccf80ddf	17
ccf80ddf LCC	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 is can be used for forwarding
	27	* @MESH_PATH_RESOLVED: the discovery process is running for this mesh path
	28	* @MESH_PATH_DSN_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_DELETE: the mesh path is scheduled to be deleted
	34	*
	35	* MESH_PATH_RESOLVED and MESH_PATH_DELETE are used by the mesh path timer to
	36	* decide when to stop or cancel the mesh path discovery.
	37	*/
	38	enum mesh_path_flags {
	39	MESH_PATH_ACTIVE = BIT(0),
	40	MESH_PATH_RESOLVING = BIT(1),
	41	MESH_PATH_DSN_VALID = BIT(2),
	42	MESH_PATH_FIXED = BIT(3),
	43	MESH_PATH_RESOLVED = BIT(4),
	44	MESH_PATH_DELETE = BIT(5),
	45	};
	46
	47	/**
	48	* struct mesh_path - mac80211 mesh path structure
	49	*
	50	* @dst: mesh path destination mac address
	51	* @dev: mesh path device
	52	* @next_hop: mesh neighbor to which frames for this destination will be
	53	* forwarded
	54	* @timer: mesh path discovery timer
	55	* @frame_queue: pending queue for frames sent to this destination while the
	56	* path is unresolved
	57	* @dsn: destination sequence number of the destination
	58	* @metric: current metric to this destination
	59	* @hop_count: hops to destination
	60	* @exp_time: in jiffies, when the path will expire or when it expired
	61	* @discovery_timeout: timeout (lapse in jiffies) used for the last discovery
	62	* retry
	63	* @discovery_retries: number of discovery retries
	64	* @flags: mesh path flags, as specified on &enum mesh_path_flags
	65	* @state_lock: mesh pat state lock
	66	*
	67	*
	68	* The combination of dst and dev is unique in the mesh path table. A reference
	69	* to the next_hop sta will be kept and in case this sta is removed, the
	70	* mesh_path structure must be also removed or substitued in a rcu safe way
	71	*/
	72	struct mesh_path {
	73	u8 dst[ETH_ALEN];
	74	struct net_device *dev;
	75	struct sta_info *next_hop;
	76	struct timer_list timer;
	77	struct sk_buff_head frame_queue;
	78	struct rcu_head rcu;
	79	u32 dsn;
	80	u32 metric;
	81	u8 hop_count;
82	unsigned long exp_time;
83	u32 discovery_timeout;
84	u8 discovery_retries;
85	enum mesh_path_flags flags;
86	spinlock_t state_lock;
87	};
88
89	/**
90	* struct mesh_table
91	*
92	* @hash_buckets: array of hash buckets of the table
93	* @hashwlock: array of locks to protect write operations, one per bucket
94	* @hash_mask: 2^size_order - 1, used to compute hash idx
95	* @hash_rnd: random value used for hash computations
96	* @entries: number of entries in the table
97	* @free_node: function to free nodes of the table
98	* @copy_node: fuction to copy nodes of the table
99	* @size_order: determines size of the table, there will be 2^size_order hash
100	* buckets
101	* @mean_chain_len: maximum average length for the hash buckets' list, if it is
102	* reached, the table will grow
103	*/
104	struct mesh_table {
105	/* Number of buckets will be 2^N */
106	struct hlist_head *hash_buckets;
107	spinlock_t hashwlock; / One per bucket, for add/del */
108	unsigned int hash_mask; /* (2^size_order) - 1 */
109	__u32 hash_rnd; /* Used for hash generation */
110	atomic_t entries; /* Up to MAX_MESH_NEIGHBOURS */
111	void (free_node) (struct hlist_node p, bool free_leafs);
112	void (copy_node) (struct hlist_node p, struct mesh_table *newtbl);
113	int size_order;
114	int mean_chain_len;
115	};
116
117	/* Recent multicast cache */
118	/* RMC_BUCKETS must be a power of 2, maximum 256 */
119	#define RMC_BUCKETS 256
120	#define RMC_QUEUE_MAX_LEN 4
121	#define RMC_TIMEOUT (3 * HZ)
122
123	/**
124	* struct rmc_entry - entry in the Recent Multicast Cache
125	*
126	* @seqnum: mesh sequence number of the frame
127	* @exp_time: expiration time of the entry, in jiffies
128	* @sa: source address of the frame
129	*
130	* The Recent Multicast Cache keeps track of the latest multicast frames that
131	* have been received by a mesh interface and discards received multicast frames
132	* that are found in the cache.
133	*/
134	struct rmc_entry {
135	struct list_head list;
136	u32 seqnum;
137	unsigned long exp_time;
138	u8 sa[ETH_ALEN];
139	};
140
141	struct mesh_rmc {
142	struct rmc_entry bucket[RMC_BUCKETS];
143	u8 idx_mask;
144	};
145
146
147	/* Mesh IEs constants */
148	#define MESH_CFG_LEN 19
149
150	/*
151	* MESH_CFG_COMP_LEN Includes:
152	* - Active path selection protocol ID.
153	* - Active path selection metric ID.
154	* - Congestion control mode identifier.
155	* - Channel precedence.
156	* Does not include mesh capabilities, which may vary across nodes in the same
157	* mesh
158	*/
159	#define MESH_CFG_CMP_LEN 17
160
161	/* Default values, timeouts in ms */
162	#define MESH_TTL 5
163	#define MESH_MAX_RETR 3
164	#define MESH_RET_T 100
165	#define MESH_CONF_T 100
166	#define MESH_HOLD_T 100
167
168	#define MESH_PATH_TIMEOUT 5000
169	/* Minimum interval between two consecutive PREQs originated by the same
170	* interface
171	*/
172	#define MESH_PREQ_MIN_INT 10
173	#define MESH_DIAM_TRAVERSAL_TIME 50
174	/* Paths will be refreshed if they are closer than PATH_REFRESH_TIME to their
175	* expiration
176	*/
177	#define MESH_PATH_REFRESH_TIME 1000
178	#define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME)
179
180	#define MESH_MAX_PREQ_RETRIES 4
181	#define MESH_PATH_EXPIRE (600 * HZ)
182
183	/* Default maximum number of established plinks per interface */
184	#define MESH_MAX_ESTAB_PLINKS 32
185
186	/* Default maximum number of plinks per interface */
187	#define MESH_MAX_PLINKS 256
188
189	/* Maximum number of paths per interface */
190	#define MESH_MAX_MPATHS 1024
191
192	/* Pending ANA approval */
193	#define PLINK_CATEGORY 30
194	#define MESH_PATH_SEL_CATEGORY 32
195
196	/* Mesh Header Flags */
197	#define IEEE80211S_FLAGS_AE 0x3
198
199	/* Public interfaces */
200	/* Various */
201	u8 mesh_id_hash(u8 *mesh_id, int mesh_id_len);
202	int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr);
203	int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
204	struct ieee80211_sub_if_data *sdata);
205	int mesh_rmc_check(u8 addr, struct ieee80211s_hdr mesh_hdr,
206	struct net_device *dev);
207	bool mesh_matches_local(struct ieee802_11_elems ie, struct net_device dev);
208	void mesh_ids_set_default(struct ieee80211_if_sta *sta);
209	void mesh_mgmt_ies_add(struct sk_buff skb, struct net_device dev);
210	void mesh_rmc_free(struct net_device *dev);
211	int mesh_rmc_init(struct net_device *dev);
212	void ieee80211s_init(void);
213	void ieee80211s_stop(void);
902acc78 JB	214	void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata);
902acc78 JB	215
ccf80ddf LCC	216	/* Mesh paths */
	217	int mesh_nexthop_lookup(u8 next_hop, struct sk_buff skb,
	218	struct net_device *dev);
	219	void mesh_path_start_discovery(struct net_device *dev);
	220	struct mesh_path mesh_path_lookup(u8 dst, struct net_device *dev);
	221	struct mesh_path mesh_path_lookup_by_idx(int idx, struct net_device dev);
	222	void mesh_path_fix_nexthop(struct mesh_path mpath, struct sta_info next_hop);
	223	void mesh_path_expire(struct net_device *dev);
	224	void mesh_path_flush(struct net_device *dev);
	225	void mesh_rx_path_sel_frame(struct net_device dev, struct ieee80211_mgmt mgmt,
	226	size_t len);
	227	int mesh_path_add(u8 dst, struct net_device dev);
	228	/* Mesh plinks */
	229	void mesh_neighbour_update(u8 hw_addr, u64 rates, struct net_device dev,
	230	bool add);
	231	bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie,
	232	struct net_device *dev);
	233	void mesh_accept_plinks_update(struct net_device *dev);
	234	struct sta_info mesh_plink_add(u8 hw_addr, u64 rates, struct net_device *dev);
	235	void mesh_plink_broken(struct sta_info *sta);
	236	void mesh_plink_deactivate(struct sta_info *sta);
	237	int mesh_plink_open(struct sta_info *sta);
	238	int mesh_plink_close(struct sta_info *sta);
	239	void mesh_plink_block(struct sta_info *sta);
	240	void mesh_rx_plink_frame(struct net_device dev, struct ieee80211_mgmt mgmt,
	241	size_t len, struct ieee80211_rx_status *rx_status);
	242
	243	/* Private interfaces */
	244	/* Mesh tables */
	245	struct mesh_table *mesh_table_alloc(int size_order);
	246	void mesh_table_free(struct mesh_table *tbl, bool free_leafs);
	247	struct mesh_table mesh_table_grow(struct mesh_table tbl);
	248	u32 mesh_table_hash(u8 addr, struct net_device dev, struct mesh_table *tbl);
	249	/* Mesh paths */
	250	int mesh_path_error_tx(u8 dest, __le32 dest_dsn, u8 ra,
	251	struct net_device *dev);
	252	void mesh_path_assign_nexthop(struct mesh_path mpath, struct sta_info sta);
	253	void mesh_path_flush_pending(struct mesh_path *mpath);
	254	void mesh_path_tx_pending(struct mesh_path *mpath);
	255	int mesh_pathtbl_init(void);
	256	void mesh_pathtbl_unregister(void);
	257	int mesh_path_del(u8 addr, struct net_device dev);
	258	void mesh_path_timer(unsigned long data);
	259	void mesh_path_flush_by_nexthop(struct sta_info *sta);
	260	void mesh_path_discard_frame(struct sk_buff skb, struct net_device dev);
	261
902acc78 JB	262	#ifdef CONFIG_MAC80211_MESH
	263	extern int mesh_allocated;
	264
ccf80ddf LCC	265	static inline int mesh_plink_free_count(struct ieee80211_sub_if_data *sdata)
	266	{
	267	return sdata->u.sta.mshcfg.dot11MeshMaxPeerLinks -
	268	atomic_read(&sdata->u.sta.mshstats.estab_plinks);
	269	}
	270
	271	static inline bool mesh_plink_availables(struct ieee80211_sub_if_data *sdata)
	272	{
	273	return (min(mesh_plink_free_count(sdata),
	274	MESH_MAX_PLINKS - sdata->local->num_sta)) > 0;
	275	}
	276
	277	static inline void mesh_path_activate(struct mesh_path *mpath)
	278	{
	279	mpath->flags \|= MESH_PATH_ACTIVE \| MESH_PATH_RESOLVED;
	280	}
	281
	282	#define for_each_mesh_entry(x, p, node, i) \
	283	for (i = 0; i <= x->hash_mask; i++) \
	284	hlist_for_each_entry_rcu(node, p, &x->hash_buckets[i], list)
	285
902acc78 JB	286	#else
	287	#define mesh_allocated 0
	288	#endif
	289
ccf80ddf LCC	290	#define MESH_PREQ(skb) (skb->cb + 30)
	291
	292	#endif /* IEEE80211S_H */