linux/net/mac80211/mesh.c
Johannes Berg 133b822638 mac80211: make master iface not wireless
There's no need to register the master netdev with cfg80211,
in fact, this is quite dangerous and lead to having to add
checks for the master interface all over the config handlers.
This patch removes the "ieee80211_ptr" from the master iface
in favour of having a small netdev_priv() associated with
the master interface that stores the ieee80211_local pointer.
Because of this, a lot of code in the configuration handlers
can go away. To make this patch easier to verify I have also
removed a number of wiphy_priv() calls in favour of getting
the sdata first and then the local pointer from that.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-09-24 16:18:00 -04:00

669 lines
18 KiB
C

/*
* 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.
*/
#include <asm/unaligned.h>
#include "ieee80211_i.h"
#include "mesh.h"
#define IEEE80211_MESH_PEER_INACTIVITY_LIMIT (1800 * HZ)
#define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
#define PP_OFFSET 1 /* Path Selection Protocol */
#define PM_OFFSET 5 /* Path Selection Metric */
#define CC_OFFSET 9 /* Congestion Control Mode */
#define CAPAB_OFFSET 17
#define ACCEPT_PLINKS 0x80
int mesh_allocated;
static struct kmem_cache *rm_cache;
void ieee80211s_init(void)
{
mesh_pathtbl_init();
mesh_allocated = 1;
rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
0, 0, NULL);
}
void ieee80211s_stop(void)
{
mesh_pathtbl_unregister();
kmem_cache_destroy(rm_cache);
}
static void ieee80211_mesh_housekeeping_timer(unsigned long data)
{
struct ieee80211_sub_if_data *sdata = (void *) data;
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
ifmsh->housekeeping = true;
queue_work(local->hw.workqueue, &ifmsh->work);
}
/**
* mesh_matches_local - check if the config of a mesh point matches ours
*
* @ie: information elements of a management frame from the mesh peer
* @sdata: local mesh subif
*
* This function checks if the mesh configuration of a mesh point matches the
* local mesh configuration, i.e. if both nodes belong to the same mesh network.
*/
bool mesh_matches_local(struct ieee802_11_elems *ie, struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
/*
* As support for each feature is added, check for matching
* - On mesh config capabilities
* - Power Save Support En
* - Sync support enabled
* - Sync support active
* - Sync support required from peer
* - MDA enabled
* - Power management control on fc
*/
if (ifmsh->mesh_id_len == ie->mesh_id_len &&
memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
memcmp(ifmsh->mesh_pp_id, ie->mesh_config + PP_OFFSET, 4) == 0 &&
memcmp(ifmsh->mesh_pm_id, ie->mesh_config + PM_OFFSET, 4) == 0 &&
memcmp(ifmsh->mesh_cc_id, ie->mesh_config + CC_OFFSET, 4) == 0)
return true;
return false;
}
/**
* mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
*
* @ie: information elements of a management frame from the mesh peer
*/
bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
{
return (*(ie->mesh_config + CAPAB_OFFSET) & ACCEPT_PLINKS) != 0;
}
/**
* mesh_accept_plinks_update: update accepting_plink in local mesh beacons
*
* @sdata: mesh interface in which mesh beacons are going to be updated
*/
void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
{
bool free_plinks;
/* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
* the mesh interface might be able to establish plinks with peers that
* are already on the table but are not on PLINK_ESTAB state. However,
* in general the mesh interface is not accepting peer link requests
* from new peers, and that must be reflected in the beacon
*/
free_plinks = mesh_plink_availables(sdata);
if (free_plinks != sdata->u.mesh.accepting_plinks)
ieee80211_mesh_housekeeping_timer((unsigned long) sdata);
}
void mesh_ids_set_default(struct ieee80211_if_mesh *sta)
{
u8 def_id[4] = {0x00, 0x0F, 0xAC, 0xff};
memcpy(sta->mesh_pp_id, def_id, 4);
memcpy(sta->mesh_pm_id, def_id, 4);
memcpy(sta->mesh_cc_id, def_id, 4);
}
int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
{
int i;
sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
if (!sdata->u.mesh.rmc)
return -ENOMEM;
sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
for (i = 0; i < RMC_BUCKETS; i++)
INIT_LIST_HEAD(&sdata->u.mesh.rmc->bucket[i].list);
return 0;
}
void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
{
struct mesh_rmc *rmc = sdata->u.mesh.rmc;
struct rmc_entry *p, *n;
int i;
if (!sdata->u.mesh.rmc)
return;
for (i = 0; i < RMC_BUCKETS; i++)
list_for_each_entry_safe(p, n, &rmc->bucket[i].list, list) {
list_del(&p->list);
kmem_cache_free(rm_cache, p);
}
kfree(rmc);
sdata->u.mesh.rmc = NULL;
}
/**
* mesh_rmc_check - Check frame in recent multicast cache and add if absent.
*
* @sa: source address
* @mesh_hdr: mesh_header
*
* Returns: 0 if the frame is not in the cache, nonzero otherwise.
*
* Checks using the source address and the mesh sequence number if we have
* received this frame lately. If the frame is not in the cache, it is added to
* it.
*/
int mesh_rmc_check(u8 *sa, struct ieee80211s_hdr *mesh_hdr,
struct ieee80211_sub_if_data *sdata)
{
struct mesh_rmc *rmc = sdata->u.mesh.rmc;
u32 seqnum = 0;
int entries = 0;
u8 idx;
struct rmc_entry *p, *n;
/* Don't care about endianness since only match matters */
memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
list_for_each_entry_safe(p, n, &rmc->bucket[idx].list, list) {
++entries;
if (time_after(jiffies, p->exp_time) ||
(entries == RMC_QUEUE_MAX_LEN)) {
list_del(&p->list);
kmem_cache_free(rm_cache, p);
--entries;
} else if ((seqnum == p->seqnum)
&& (memcmp(sa, p->sa, ETH_ALEN) == 0))
return -1;
}
p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
if (!p) {
printk(KERN_DEBUG "o11s: could not allocate RMC entry\n");
return 0;
}
p->seqnum = seqnum;
p->exp_time = jiffies + RMC_TIMEOUT;
memcpy(p->sa, sa, ETH_ALEN);
list_add(&p->list, &rmc->bucket[idx].list);
return 0;
}
void mesh_mgmt_ies_add(struct sk_buff *skb, struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_supported_band *sband;
u8 *pos;
int len, i, rate;
sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
len = sband->n_bitrates;
if (len > 8)
len = 8;
pos = skb_put(skb, len + 2);
*pos++ = WLAN_EID_SUPP_RATES;
*pos++ = len;
for (i = 0; i < len; i++) {
rate = sband->bitrates[i].bitrate;
*pos++ = (u8) (rate / 5);
}
if (sband->n_bitrates > len) {
pos = skb_put(skb, sband->n_bitrates - len + 2);
*pos++ = WLAN_EID_EXT_SUPP_RATES;
*pos++ = sband->n_bitrates - len;
for (i = len; i < sband->n_bitrates; i++) {
rate = sband->bitrates[i].bitrate;
*pos++ = (u8) (rate / 5);
}
}
pos = skb_put(skb, 2 + sdata->u.mesh.mesh_id_len);
*pos++ = WLAN_EID_MESH_ID;
*pos++ = sdata->u.mesh.mesh_id_len;
if (sdata->u.mesh.mesh_id_len)
memcpy(pos, sdata->u.mesh.mesh_id, sdata->u.mesh.mesh_id_len);
pos = skb_put(skb, 21);
*pos++ = WLAN_EID_MESH_CONFIG;
*pos++ = MESH_CFG_LEN;
/* Version */
*pos++ = 1;
/* Active path selection protocol ID */
memcpy(pos, sdata->u.mesh.mesh_pp_id, 4);
pos += 4;
/* Active path selection metric ID */
memcpy(pos, sdata->u.mesh.mesh_pm_id, 4);
pos += 4;
/* Congestion control mode identifier */
memcpy(pos, sdata->u.mesh.mesh_cc_id, 4);
pos += 4;
/* Channel precedence:
* Not running simple channel unification protocol
*/
memset(pos, 0x00, 4);
pos += 4;
/* Mesh capability */
sdata->u.mesh.accepting_plinks = mesh_plink_availables(sdata);
*pos++ = sdata->u.mesh.accepting_plinks ? ACCEPT_PLINKS : 0x00;
*pos++ = 0x00;
return;
}
u32 mesh_table_hash(u8 *addr, struct ieee80211_sub_if_data *sdata, struct mesh_table *tbl)
{
/* Use last four bytes of hw addr and interface index as hash index */
return jhash_2words(*(u32 *)(addr+2), sdata->dev->ifindex, tbl->hash_rnd)
& tbl->hash_mask;
}
u8 mesh_id_hash(u8 *mesh_id, int mesh_id_len)
{
if (!mesh_id_len)
return 1;
else if (mesh_id_len == 1)
return (u8) mesh_id[0];
else
return (u8) (mesh_id[0] + 2 * mesh_id[1]);
}
struct mesh_table *mesh_table_alloc(int size_order)
{
int i;
struct mesh_table *newtbl;
newtbl = kmalloc(sizeof(struct mesh_table), GFP_KERNEL);
if (!newtbl)
return NULL;
newtbl->hash_buckets = kzalloc(sizeof(struct hlist_head) *
(1 << size_order), GFP_KERNEL);
if (!newtbl->hash_buckets) {
kfree(newtbl);
return NULL;
}
newtbl->hashwlock = kmalloc(sizeof(spinlock_t) *
(1 << size_order), GFP_KERNEL);
if (!newtbl->hashwlock) {
kfree(newtbl->hash_buckets);
kfree(newtbl);
return NULL;
}
newtbl->size_order = size_order;
newtbl->hash_mask = (1 << size_order) - 1;
atomic_set(&newtbl->entries, 0);
get_random_bytes(&newtbl->hash_rnd,
sizeof(newtbl->hash_rnd));
for (i = 0; i <= newtbl->hash_mask; i++)
spin_lock_init(&newtbl->hashwlock[i]);
return newtbl;
}
static void __mesh_table_free(struct mesh_table *tbl)
{
kfree(tbl->hash_buckets);
kfree(tbl->hashwlock);
kfree(tbl);
}
void mesh_table_free(struct mesh_table *tbl, bool free_leafs)
{
struct hlist_head *mesh_hash;
struct hlist_node *p, *q;
int i;
mesh_hash = tbl->hash_buckets;
for (i = 0; i <= tbl->hash_mask; i++) {
spin_lock(&tbl->hashwlock[i]);
hlist_for_each_safe(p, q, &mesh_hash[i]) {
tbl->free_node(p, free_leafs);
atomic_dec(&tbl->entries);
}
spin_unlock(&tbl->hashwlock[i]);
}
__mesh_table_free(tbl);
}
static void ieee80211_mesh_path_timer(unsigned long data)
{
struct ieee80211_sub_if_data *sdata =
(struct ieee80211_sub_if_data *) data;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct ieee80211_local *local = sdata->local;
queue_work(local->hw.workqueue, &ifmsh->work);
}
struct mesh_table *mesh_table_grow(struct mesh_table *tbl)
{
struct mesh_table *newtbl;
struct hlist_head *oldhash;
struct hlist_node *p, *q;
int i;
if (atomic_read(&tbl->entries)
< tbl->mean_chain_len * (tbl->hash_mask + 1))
goto endgrow;
newtbl = mesh_table_alloc(tbl->size_order + 1);
if (!newtbl)
goto endgrow;
newtbl->free_node = tbl->free_node;
newtbl->mean_chain_len = tbl->mean_chain_len;
newtbl->copy_node = tbl->copy_node;
atomic_set(&newtbl->entries, atomic_read(&tbl->entries));
oldhash = tbl->hash_buckets;
for (i = 0; i <= tbl->hash_mask; i++)
hlist_for_each(p, &oldhash[i])
if (tbl->copy_node(p, newtbl) < 0)
goto errcopy;
return newtbl;
errcopy:
for (i = 0; i <= newtbl->hash_mask; i++) {
hlist_for_each_safe(p, q, &newtbl->hash_buckets[i])
tbl->free_node(p, 0);
}
__mesh_table_free(newtbl);
endgrow:
return NULL;
}
/**
* ieee80211_new_mesh_header - create a new mesh header
* @meshhdr: uninitialized mesh header
* @sdata: mesh interface to be used
*
* Return the header length.
*/
int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
struct ieee80211_sub_if_data *sdata)
{
meshhdr->flags = 0;
meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
sdata->u.mesh.mesh_seqnum++;
return 6;
}
static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata,
struct ieee80211_if_mesh *ifmsh)
{
bool free_plinks;
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
printk(KERN_DEBUG "%s: running mesh housekeeping\n",
sdata->dev->name);
#endif
ieee80211_sta_expire(sdata, IEEE80211_MESH_PEER_INACTIVITY_LIMIT);
mesh_path_expire(sdata);
free_plinks = mesh_plink_availables(sdata);
if (free_plinks != sdata->u.mesh.accepting_plinks)
ieee80211_if_config(sdata, IEEE80211_IFCC_BEACON);
ifmsh->housekeeping = false;
mod_timer(&ifmsh->housekeeping_timer,
round_jiffies(jiffies + IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
}
void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct ieee80211_local *local = sdata->local;
ifmsh->housekeeping = true;
queue_work(local->hw.workqueue, &ifmsh->work);
ieee80211_if_config(sdata, IEEE80211_IFCC_BEACON);
}
void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
{
del_timer_sync(&sdata->u.mesh.housekeeping_timer);
/*
* If the timer fired while we waited for it, it will have
* requeued the work. Now the work will be running again
* but will not rearm the timer again because it checks
* whether the interface is running, which, at this point,
* it no longer is.
*/
cancel_work_sync(&sdata->u.mesh.work);
/*
* When we get here, the interface is marked down.
* Call synchronize_rcu() to wait for the RX path
* should it be using the interface and enqueuing
* frames at this very time on another CPU.
*/
synchronize_rcu();
skb_queue_purge(&sdata->u.mesh.skb_queue);
}
static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
u16 stype,
struct ieee80211_mgmt *mgmt,
size_t len,
struct ieee80211_rx_status *rx_status)
{
struct ieee80211_local *local= sdata->local;
struct ieee802_11_elems elems;
struct ieee80211_channel *channel;
u64 supp_rates = 0;
size_t baselen;
int freq;
enum ieee80211_band band = rx_status->band;
/* ignore ProbeResp to foreign address */
if (stype == IEEE80211_STYPE_PROBE_RESP &&
compare_ether_addr(mgmt->da, sdata->dev->dev_addr))
return;
baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
if (baselen > len)
return;
ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
&elems);
if (elems.ds_params && elems.ds_params_len == 1)
freq = ieee80211_channel_to_frequency(elems.ds_params[0]);
else
freq = rx_status->freq;
channel = ieee80211_get_channel(local->hw.wiphy, freq);
if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
return;
if (elems.mesh_id && elems.mesh_config &&
mesh_matches_local(&elems, sdata)) {
supp_rates = ieee80211_sta_get_rates(local, &elems, band);
mesh_neighbour_update(mgmt->sa, supp_rates, sdata,
mesh_peer_accepts_plinks(&elems));
}
}
static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
size_t len,
struct ieee80211_rx_status *rx_status)
{
switch (mgmt->u.action.category) {
case PLINK_CATEGORY:
mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
break;
case MESH_PATH_SEL_CATEGORY:
mesh_rx_path_sel_frame(sdata, mgmt, len);
break;
}
}
static void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb)
{
struct ieee80211_rx_status *rx_status;
struct ieee80211_if_mesh *ifmsh;
struct ieee80211_mgmt *mgmt;
u16 stype;
ifmsh = &sdata->u.mesh;
rx_status = (struct ieee80211_rx_status *) skb->cb;
mgmt = (struct ieee80211_mgmt *) skb->data;
stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
switch (stype) {
case IEEE80211_STYPE_PROBE_RESP:
case IEEE80211_STYPE_BEACON:
ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
rx_status);
break;
case IEEE80211_STYPE_ACTION:
ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
break;
}
kfree_skb(skb);
}
static void ieee80211_mesh_work(struct work_struct *work)
{
struct ieee80211_sub_if_data *sdata =
container_of(work, struct ieee80211_sub_if_data, u.mesh.work);
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct sk_buff *skb;
if (!netif_running(sdata->dev))
return;
if (local->sw_scanning || local->hw_scanning)
return;
while ((skb = skb_dequeue(&ifmsh->skb_queue)))
ieee80211_mesh_rx_queued_mgmt(sdata, skb);
if (ifmsh->preq_queue_len &&
time_after(jiffies,
ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
mesh_path_start_discovery(sdata);
if (ifmsh->housekeeping)
ieee80211_mesh_housekeeping(sdata, ifmsh);
}
void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
{
struct ieee80211_sub_if_data *sdata;
rcu_read_lock();
list_for_each_entry_rcu(sdata, &local->interfaces, list)
if (ieee80211_vif_is_mesh(&sdata->vif))
queue_work(local->hw.workqueue, &sdata->u.mesh.work);
rcu_read_unlock();
}
void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
INIT_WORK(&ifmsh->work, ieee80211_mesh_work);
setup_timer(&ifmsh->housekeeping_timer,
ieee80211_mesh_housekeeping_timer,
(unsigned long) sdata);
skb_queue_head_init(&sdata->u.mesh.skb_queue);
ifmsh->mshcfg.dot11MeshRetryTimeout = MESH_RET_T;
ifmsh->mshcfg.dot11MeshConfirmTimeout = MESH_CONF_T;
ifmsh->mshcfg.dot11MeshHoldingTimeout = MESH_HOLD_T;
ifmsh->mshcfg.dot11MeshMaxRetries = MESH_MAX_RETR;
ifmsh->mshcfg.dot11MeshTTL = MESH_TTL;
ifmsh->mshcfg.auto_open_plinks = true;
ifmsh->mshcfg.dot11MeshMaxPeerLinks =
MESH_MAX_ESTAB_PLINKS;
ifmsh->mshcfg.dot11MeshHWMPactivePathTimeout =
MESH_PATH_TIMEOUT;
ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval =
MESH_PREQ_MIN_INT;
ifmsh->mshcfg.dot11MeshHWMPnetDiameterTraversalTime =
MESH_DIAM_TRAVERSAL_TIME;
ifmsh->mshcfg.dot11MeshHWMPmaxPREQretries =
MESH_MAX_PREQ_RETRIES;
ifmsh->mshcfg.path_refresh_time =
MESH_PATH_REFRESH_TIME;
ifmsh->mshcfg.min_discovery_timeout =
MESH_MIN_DISCOVERY_TIMEOUT;
ifmsh->accepting_plinks = true;
ifmsh->preq_id = 0;
ifmsh->dsn = 0;
atomic_set(&ifmsh->mpaths, 0);
mesh_rmc_init(sdata);
ifmsh->last_preq = jiffies;
/* Allocate all mesh structures when creating the first mesh interface. */
if (!mesh_allocated)
ieee80211s_init();
mesh_ids_set_default(ifmsh);
setup_timer(&ifmsh->mesh_path_timer,
ieee80211_mesh_path_timer,
(unsigned long) sdata);
INIT_LIST_HEAD(&ifmsh->preq_queue.list);
spin_lock_init(&ifmsh->mesh_preq_queue_lock);
}
ieee80211_rx_result
ieee80211_mesh_rx_mgmt(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
struct ieee80211_rx_status *rx_status)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct ieee80211_mgmt *mgmt;
u16 fc;
if (skb->len < 24)
return RX_DROP_MONITOR;
mgmt = (struct ieee80211_mgmt *) skb->data;
fc = le16_to_cpu(mgmt->frame_control);
switch (fc & IEEE80211_FCTL_STYPE) {
case IEEE80211_STYPE_PROBE_RESP:
case IEEE80211_STYPE_BEACON:
case IEEE80211_STYPE_ACTION:
memcpy(skb->cb, rx_status, sizeof(*rx_status));
skb_queue_tail(&ifmsh->skb_queue, skb);
queue_work(local->hw.workqueue, &ifmsh->work);
return RX_QUEUED;
}
return RX_CONTINUE;
}