// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2008, 2009 open80211s Ltd. * Copyright (C) 2023 Intel Corporation * Author: Luis Carlos Cobo */ #include #include #include #include #include #include #include #include "wme.h" #include "ieee80211_i.h" #include "mesh.h" #include static void mesh_path_free_rcu(struct mesh_table *tbl, struct mesh_path *mpath); static u32 mesh_table_hash(const void *addr, u32 len, u32 seed) { /* Use last four bytes of hw addr as hash index */ return jhash_1word(__get_unaligned_cpu32((u8 *)addr + 2), seed); } static const struct rhashtable_params mesh_rht_params = { .nelem_hint = 2, .automatic_shrinking = true, .key_len = ETH_ALEN, .key_offset = offsetof(struct mesh_path, dst), .head_offset = offsetof(struct mesh_path, rhash), .hashfn = mesh_table_hash, }; static const struct rhashtable_params fast_tx_rht_params = { .nelem_hint = 10, .automatic_shrinking = true, .key_len = sizeof_field(struct ieee80211_mesh_fast_tx, key), .key_offset = offsetof(struct ieee80211_mesh_fast_tx, key), .head_offset = offsetof(struct ieee80211_mesh_fast_tx, rhash), .hashfn = mesh_table_hash, }; static void __mesh_fast_tx_entry_free(void *ptr, void *tblptr) { struct ieee80211_mesh_fast_tx *entry = ptr; kfree_rcu(entry, fast_tx.rcu_head); } static void mesh_fast_tx_deinit(struct ieee80211_sub_if_data *sdata) { struct mesh_tx_cache *cache; cache = &sdata->u.mesh.tx_cache; rhashtable_free_and_destroy(&cache->rht, __mesh_fast_tx_entry_free, NULL); } static void mesh_fast_tx_init(struct ieee80211_sub_if_data *sdata) { struct mesh_tx_cache *cache; cache = &sdata->u.mesh.tx_cache; rhashtable_init(&cache->rht, &fast_tx_rht_params); INIT_HLIST_HEAD(&cache->walk_head); spin_lock_init(&cache->walk_lock); } static inline bool mpath_expired(struct mesh_path *mpath) { return (mpath->flags & MESH_PATH_ACTIVE) && time_after(jiffies, mpath->exp_time) && !(mpath->flags & MESH_PATH_FIXED); } static void mesh_path_rht_free(void *ptr, void *tblptr) { struct mesh_path *mpath = ptr; struct mesh_table *tbl = tblptr; mesh_path_free_rcu(tbl, mpath); } static void mesh_table_init(struct mesh_table *tbl) { INIT_HLIST_HEAD(&tbl->known_gates); INIT_HLIST_HEAD(&tbl->walk_head); atomic_set(&tbl->entries, 0); spin_lock_init(&tbl->gates_lock); spin_lock_init(&tbl->walk_lock); /* rhashtable_init() may fail only in case of wrong * mesh_rht_params */ WARN_ON(rhashtable_init(&tbl->rhead, &mesh_rht_params)); } static void mesh_table_free(struct mesh_table *tbl) { rhashtable_free_and_destroy(&tbl->rhead, mesh_path_rht_free, tbl); } /** * mesh_path_assign_nexthop - update mesh path next hop * * @mpath: mesh path to update * @sta: next hop to assign * * Locking: mpath->state_lock must be held when calling this function */ void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta) { struct sk_buff *skb; struct ieee80211_hdr *hdr; unsigned long flags; rcu_assign_pointer(mpath->next_hop, sta); spin_lock_irqsave(&mpath->frame_queue.lock, flags); skb_queue_walk(&mpath->frame_queue, skb) { hdr = (struct ieee80211_hdr *) skb->data; memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN); memcpy(hdr->addr2, mpath->sdata->vif.addr, ETH_ALEN); ieee80211_mps_set_frame_flags(sta->sdata, sta, hdr); } spin_unlock_irqrestore(&mpath->frame_queue.lock, flags); } static void prepare_for_gate(struct sk_buff *skb, char *dst_addr, struct mesh_path *gate_mpath) { struct ieee80211_hdr *hdr; struct ieee80211s_hdr *mshdr; int mesh_hdrlen, hdrlen; char *next_hop; hdr = (struct ieee80211_hdr *) skb->data; hdrlen = ieee80211_hdrlen(hdr->frame_control); mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); if (!(mshdr->flags & MESH_FLAGS_AE)) { /* size of the fixed part of the mesh header */ mesh_hdrlen = 6; /* make room for the two extended addresses */ skb_push(skb, 2 * ETH_ALEN); memmove(skb->data, hdr, hdrlen + mesh_hdrlen); hdr = (struct ieee80211_hdr *) skb->data; /* we preserve the previous mesh header and only add * the new addresses */ mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); mshdr->flags = MESH_FLAGS_AE_A5_A6; memcpy(mshdr->eaddr1, hdr->addr3, ETH_ALEN); memcpy(mshdr->eaddr2, hdr->addr4, ETH_ALEN); } /* update next hop */ hdr = (struct ieee80211_hdr *) skb->data; rcu_read_lock(); next_hop = rcu_dereference(gate_mpath->next_hop)->sta.addr; memcpy(hdr->addr1, next_hop, ETH_ALEN); rcu_read_unlock(); memcpy(hdr->addr2, gate_mpath->sdata->vif.addr, ETH_ALEN); memcpy(hdr->addr3, dst_addr, ETH_ALEN); } /** * mesh_path_move_to_queue - Move or copy frames from one mpath queue to another * * @gate_mpath: An active mpath the frames will be sent to (i.e. the gate) * @from_mpath: The failed mpath * @copy: When true, copy all the frames to the new mpath queue. When false, * move them. * * This function is used to transfer or copy frames from an unresolved mpath to * a gate mpath. The function also adds the Address Extension field and * updates the next hop. * * If a frame already has an Address Extension field, only the next hop and * destination addresses are updated. * * The gate mpath must be an active mpath with a valid mpath->next_hop. */ static void mesh_path_move_to_queue(struct mesh_path *gate_mpath, struct mesh_path *from_mpath, bool copy) { struct sk_buff *skb, *fskb, *tmp; struct sk_buff_head failq; unsigned long flags; if (WARN_ON(gate_mpath == from_mpath)) return; if (WARN_ON(!gate_mpath->next_hop)) return; __skb_queue_head_init(&failq); spin_lock_irqsave(&from_mpath->frame_queue.lock, flags); skb_queue_splice_init(&from_mpath->frame_queue, &failq); spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags); skb_queue_walk_safe(&failq, fskb, tmp) { if (skb_queue_len(&gate_mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN) { mpath_dbg(gate_mpath->sdata, "mpath queue full!\n"); break; } skb = skb_copy(fskb, GFP_ATOMIC); if (WARN_ON(!skb)) break; prepare_for_gate(skb, gate_mpath->dst, gate_mpath); skb_queue_tail(&gate_mpath->frame_queue, skb); if (copy) continue; __skb_unlink(fskb, &failq); kfree_skb(fskb); } mpath_dbg(gate_mpath->sdata, "Mpath queue for gate %pM has %d frames\n", gate_mpath->dst, skb_queue_len(&gate_mpath->frame_queue)); if (!copy) return; spin_lock_irqsave(&from_mpath->frame_queue.lock, flags); skb_queue_splice(&failq, &from_mpath->frame_queue); spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags); } static struct mesh_path *mpath_lookup(struct mesh_table *tbl, const u8 *dst, struct ieee80211_sub_if_data *sdata) { struct mesh_path *mpath; mpath = rhashtable_lookup(&tbl->rhead, dst, mesh_rht_params); if (mpath && mpath_expired(mpath)) { spin_lock_bh(&mpath->state_lock); mpath->flags &= ~MESH_PATH_ACTIVE; spin_unlock_bh(&mpath->state_lock); } return mpath; } /** * mesh_path_lookup - look up a path in the mesh path table * @sdata: local subif * @dst: hardware address (ETH_ALEN length) of destination * * Returns: pointer to the mesh path structure, or NULL if not found * * Locking: must be called within a read rcu section. */ struct mesh_path * mesh_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst) { return mpath_lookup(&sdata->u.mesh.mesh_paths, dst, sdata); } struct mesh_path * mpp_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst) { return mpath_lookup(&sdata->u.mesh.mpp_paths, dst, sdata); } static struct mesh_path * __mesh_path_lookup_by_idx(struct mesh_table *tbl, int idx) { int i = 0; struct mesh_path *mpath; hlist_for_each_entry_rcu(mpath, &tbl->walk_head, walk_list) { if (i++ == idx) break; } if (!mpath) return NULL; if (mpath_expired(mpath)) { spin_lock_bh(&mpath->state_lock); mpath->flags &= ~MESH_PATH_ACTIVE; spin_unlock_bh(&mpath->state_lock); } return mpath; } /** * mesh_path_lookup_by_idx - look up a path in the mesh path table by its index * @sdata: local subif, or NULL for all entries * @idx: index * * Returns: pointer to the mesh path structure, or NULL if not found. * * Locking: must be called within a read rcu section. */ struct mesh_path * mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx) { return __mesh_path_lookup_by_idx(&sdata->u.mesh.mesh_paths, idx); } /** * mpp_path_lookup_by_idx - look up a path in the proxy path table by its index * @sdata: local subif, or NULL for all entries * @idx: index * * Returns: pointer to the proxy path structure, or NULL if not found. * * Locking: must be called within a read rcu section. */ struct mesh_path * mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx) { return __mesh_path_lookup_by_idx(&sdata->u.mesh.mpp_paths, idx); } /** * mesh_path_add_gate - add the given mpath to a mesh gate to our path table * @mpath: gate path to add to table * * Returns: 0 on success, -EEXIST */ int mesh_path_add_gate(struct mesh_path *mpath) { struct mesh_table *tbl; int err; rcu_read_lock(); tbl = &mpath->sdata->u.mesh.mesh_paths; spin_lock_bh(&mpath->state_lock); if (mpath->is_gate) { err = -EEXIST; spin_unlock_bh(&mpath->state_lock); goto err_rcu; } mpath->is_gate = true; mpath->sdata->u.mesh.num_gates++; spin_lock(&tbl->gates_lock); hlist_add_head_rcu(&mpath->gate_list, &tbl->known_gates); spin_unlock(&tbl->gates_lock); spin_unlock_bh(&mpath->state_lock); mpath_dbg(mpath->sdata, "Mesh path: Recorded new gate: %pM. %d known gates\n", mpath->dst, mpath->sdata->u.mesh.num_gates); err = 0; err_rcu: rcu_read_unlock(); return err; } /** * mesh_gate_del - remove a mesh gate from the list of known gates * @tbl: table which holds our list of known gates * @mpath: gate mpath */ static void mesh_gate_del(struct mesh_table *tbl, struct mesh_path *mpath) { lockdep_assert_held(&mpath->state_lock); if (!mpath->is_gate) return; mpath->is_gate = false; spin_lock_bh(&tbl->gates_lock); hlist_del_rcu(&mpath->gate_list); mpath->sdata->u.mesh.num_gates--; spin_unlock_bh(&tbl->gates_lock); mpath_dbg(mpath->sdata, "Mesh path: Deleted gate: %pM. %d known gates\n", mpath->dst, mpath->sdata->u.mesh.num_gates); } /** * mesh_gate_num - number of gates known to this interface * @sdata: subif data * * Returns: The number of gates */ int mesh_gate_num(struct ieee80211_sub_if_data *sdata) { return sdata->u.mesh.num_gates; } static struct mesh_path *mesh_path_new(struct ieee80211_sub_if_data *sdata, const u8 *dst, gfp_t gfp_flags) { struct mesh_path *new_mpath; new_mpath = kzalloc(sizeof(struct mesh_path), gfp_flags); if (!new_mpath) return NULL; memcpy(new_mpath->dst, dst, ETH_ALEN); eth_broadcast_addr(new_mpath->rann_snd_addr); new_mpath->is_root = false; new_mpath->sdata = sdata; new_mpath->flags = 0; skb_queue_head_init(&new_mpath->frame_queue); new_mpath->exp_time = jiffies; spin_lock_init(&new_mpath->state_lock); timer_setup(&new_mpath->timer, mesh_path_timer, 0); return new_mpath; } static void mesh_fast_tx_entry_free(struct mesh_tx_cache *cache, struct ieee80211_mesh_fast_tx *entry) { hlist_del_rcu(&entry->walk_list); rhashtable_remove_fast(&cache->rht, &entry->rhash, fast_tx_rht_params); kfree_rcu(entry, fast_tx.rcu_head); } struct ieee80211_mesh_fast_tx * mesh_fast_tx_get(struct ieee80211_sub_if_data *sdata, struct ieee80211_mesh_fast_tx_key *key) { struct ieee80211_mesh_fast_tx *entry; struct mesh_tx_cache *cache; cache = &sdata->u.mesh.tx_cache; entry = rhashtable_lookup(&cache->rht, key, fast_tx_rht_params); if (!entry) return NULL; if (!(entry->mpath->flags & MESH_PATH_ACTIVE) || mpath_expired(entry->mpath)) { spin_lock_bh(&cache->walk_lock); entry = rhashtable_lookup(&cache->rht, key, fast_tx_rht_params); if (entry) mesh_fast_tx_entry_free(cache, entry); spin_unlock_bh(&cache->walk_lock); return NULL; } mesh_path_refresh(sdata, entry->mpath, NULL); if (entry->mppath) entry->mppath->exp_time = jiffies; entry->timestamp = jiffies; return entry; } void mesh_fast_tx_cache(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb, struct mesh_path *mpath) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); struct ieee80211_mesh_fast_tx *entry, *prev; struct ieee80211_mesh_fast_tx build = {}; struct ieee80211s_hdr *meshhdr; struct mesh_tx_cache *cache; struct ieee80211_key *key; struct mesh_path *mppath; struct sta_info *sta; u8 *qc; if (sdata->noack_map || !ieee80211_is_data_qos(hdr->frame_control)) return; build.fast_tx.hdr_len = ieee80211_hdrlen(hdr->frame_control); meshhdr = (struct ieee80211s_hdr *)(skb->data + build.fast_tx.hdr_len); build.hdrlen = ieee80211_get_mesh_hdrlen(meshhdr); cache = &sdata->u.mesh.tx_cache; if (atomic_read(&cache->rht.nelems) >= MESH_FAST_TX_CACHE_MAX_SIZE) return; sta = rcu_dereference(mpath->next_hop); if (!sta) return; build.key.type = MESH_FAST_TX_TYPE_LOCAL; if ((meshhdr->flags & MESH_FLAGS_AE) == MESH_FLAGS_AE_A5_A6) { /* This is required to keep the mppath alive */ mppath = mpp_path_lookup(sdata, meshhdr->eaddr1); if (!mppath) return; build.mppath = mppath; if (!ether_addr_equal(meshhdr->eaddr2, sdata->vif.addr)) build.key.type = MESH_FAST_TX_TYPE_PROXIED; } else if (ieee80211_has_a4(hdr->frame_control)) { mppath = mpath; } else { return; } if (!ether_addr_equal(hdr->addr4, sdata->vif.addr)) build.key.type = MESH_FAST_TX_TYPE_FORWARDED; /* rate limit, in case fast xmit can't be enabled */ if (mppath->fast_tx_check == jiffies) return; mppath->fast_tx_check = jiffies; /* * Same use of the sta lock as in ieee80211_check_fast_xmit, in order * to protect against concurrent sta key updates. */ spin_lock_bh(&sta->lock); key = rcu_access_pointer(sta->ptk[sta->ptk_idx]); if (!key) key = rcu_access_pointer(sdata->default_unicast_key); build.fast_tx.key = key; if (key) { bool gen_iv, iv_spc; gen_iv = key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV; iv_spc = key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE; if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) || (key->flags & KEY_FLAG_TAINTED)) goto unlock_sta; switch (key->conf.cipher) { case WLAN_CIPHER_SUITE_CCMP: case WLAN_CIPHER_SUITE_CCMP_256: if (gen_iv) build.fast_tx.pn_offs = build.fast_tx.hdr_len; if (gen_iv || iv_spc) build.fast_tx.hdr_len += IEEE80211_CCMP_HDR_LEN; break; case WLAN_CIPHER_SUITE_GCMP: case WLAN_CIPHER_SUITE_GCMP_256: if (gen_iv) build.fast_tx.pn_offs = build.fast_tx.hdr_len; if (gen_iv || iv_spc) build.fast_tx.hdr_len += IEEE80211_GCMP_HDR_LEN; break; default: goto unlock_sta; } } memcpy(build.key.addr, mppath->dst, ETH_ALEN); build.timestamp = jiffies; build.fast_tx.band = info->band; build.fast_tx.da_offs = offsetof(struct ieee80211_hdr, addr3); build.fast_tx.sa_offs = offsetof(struct ieee80211_hdr, addr4); build.mpath = mpath; memcpy(build.hdr, meshhdr, build.hdrlen); memcpy(build.hdr + build.hdrlen, rfc1042_header, sizeof(rfc1042_header)); build.hdrlen += sizeof(rfc1042_header); memcpy(build.fast_tx.hdr, hdr, build.fast_tx.hdr_len); hdr = (struct ieee80211_hdr *)build.fast_tx.hdr; if (build.fast_tx.key) hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); qc = ieee80211_get_qos_ctl(hdr); qc[1] |= IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8; entry = kmemdup(&build, sizeof(build), GFP_ATOMIC); if (!entry) goto unlock_sta; spin_lock(&cache->walk_lock); prev = rhashtable_lookup_get_insert_fast(&cache->rht, &entry->rhash, fast_tx_rht_params); if (IS_ERR(prev)) { kfree(entry); goto unlock_cache; } /* * replace any previous entry in the hash table, in case we're * replacing it with a different type (e.g. mpath -> mpp) */ if (unlikely(prev)) { rhashtable_replace_fast(&cache->rht, &prev->rhash, &entry->rhash, fast_tx_rht_params); hlist_del_rcu(&prev->walk_list); kfree_rcu(prev, fast_tx.rcu_head); } hlist_add_head(&entry->walk_list, &cache->walk_head); unlock_cache: spin_unlock(&cache->walk_lock); unlock_sta: spin_unlock_bh(&sta->lock); } void mesh_fast_tx_gc(struct ieee80211_sub_if_data *sdata) { unsigned long timeout = msecs_to_jiffies(MESH_FAST_TX_CACHE_TIMEOUT); struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache; struct ieee80211_mesh_fast_tx *entry; struct hlist_node *n; if (atomic_read(&cache->rht.nelems) < MESH_FAST_TX_CACHE_THRESHOLD_SIZE) return; spin_lock_bh(&cache->walk_lock); hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list) if (!time_is_after_jiffies(entry->timestamp + timeout)) mesh_fast_tx_entry_free(cache, entry); spin_unlock_bh(&cache->walk_lock); } void mesh_fast_tx_flush_mpath(struct mesh_path *mpath) { struct ieee80211_sub_if_data *sdata = mpath->sdata; struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache; struct ieee80211_mesh_fast_tx *entry; struct hlist_node *n; spin_lock_bh(&cache->walk_lock); hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list) if (entry->mpath == mpath) mesh_fast_tx_entry_free(cache, entry); spin_unlock_bh(&cache->walk_lock); } void mesh_fast_tx_flush_sta(struct ieee80211_sub_if_data *sdata, struct sta_info *sta) { struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache; struct ieee80211_mesh_fast_tx *entry; struct hlist_node *n; spin_lock_bh(&cache->walk_lock); hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list) if (rcu_access_pointer(entry->mpath->next_hop) == sta) mesh_fast_tx_entry_free(cache, entry); spin_unlock_bh(&cache->walk_lock); } void mesh_fast_tx_flush_addr(struct ieee80211_sub_if_data *sdata, const u8 *addr) { struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache; struct ieee80211_mesh_fast_tx_key key = {}; struct ieee80211_mesh_fast_tx *entry; int i; ether_addr_copy(key.addr, addr); spin_lock_bh(&cache->walk_lock); for (i = 0; i < NUM_MESH_FAST_TX_TYPE; i++) { key.type = i; entry = rhashtable_lookup_fast(&cache->rht, &key, fast_tx_rht_params); if (entry) mesh_fast_tx_entry_free(cache, entry); } spin_unlock_bh(&cache->walk_lock); } /** * mesh_path_add - allocate and add a new path to the mesh path table * @sdata: local subif * @dst: destination address of the path (ETH_ALEN length) * * Returns: 0 on success * * State: the initial state of the new path is set to 0 */ struct mesh_path *mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst) { struct mesh_table *tbl; struct mesh_path *mpath, *new_mpath; if (ether_addr_equal(dst, sdata->vif.addr)) /* never add ourselves as neighbours */ return ERR_PTR(-EOPNOTSUPP); if (is_multicast_ether_addr(dst)) return ERR_PTR(-EOPNOTSUPP); if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0) return ERR_PTR(-ENOSPC); new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC); if (!new_mpath) return ERR_PTR(-ENOMEM); tbl = &sdata->u.mesh.mesh_paths; spin_lock_bh(&tbl->walk_lock); mpath = rhashtable_lookup_get_insert_fast(&tbl->rhead, &new_mpath->rhash, mesh_rht_params); if (!mpath) hlist_add_head(&new_mpath->walk_list, &tbl->walk_head); spin_unlock_bh(&tbl->walk_lock); if (mpath) { kfree(new_mpath); if (IS_ERR(mpath)) return mpath; new_mpath = mpath; } sdata->u.mesh.mesh_paths_generation++; return new_mpath; } int mpp_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst, const u8 *mpp) { struct mesh_table *tbl; struct mesh_path *new_mpath; int ret; if (ether_addr_equal(dst, sdata->vif.addr)) /* never add ourselves as neighbours */ return -EOPNOTSUPP; if (is_multicast_ether_addr(dst)) return -EOPNOTSUPP; new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC); if (!new_mpath) return -ENOMEM; memcpy(new_mpath->mpp, mpp, ETH_ALEN); tbl = &sdata->u.mesh.mpp_paths; spin_lock_bh(&tbl->walk_lock); ret = rhashtable_lookup_insert_fast(&tbl->rhead, &new_mpath->rhash, mesh_rht_params); if (!ret) hlist_add_head_rcu(&new_mpath->walk_list, &tbl->walk_head); spin_unlock_bh(&tbl->walk_lock); if (ret) kfree(new_mpath); else mesh_fast_tx_flush_addr(sdata, dst); sdata->u.mesh.mpp_paths_generation++; return ret; } /** * mesh_plink_broken - deactivates paths and sends perr when a link breaks * * @sta: broken peer link * * This function must be called from the rate control algorithm if enough * delivery errors suggest that a peer link is no longer usable. */ void mesh_plink_broken(struct sta_info *sta) { struct ieee80211_sub_if_data *sdata = sta->sdata; struct mesh_table *tbl = &sdata->u.mesh.mesh_paths; static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; struct mesh_path *mpath; rcu_read_lock(); hlist_for_each_entry_rcu(mpath, &tbl->walk_head, walk_list) { if (rcu_access_pointer(mpath->next_hop) == sta && mpath->flags & MESH_PATH_ACTIVE && !(mpath->flags & MESH_PATH_FIXED)) { spin_lock_bh(&mpath->state_lock); mpath->flags &= ~MESH_PATH_ACTIVE; ++mpath->sn; spin_unlock_bh(&mpath->state_lock); mesh_path_error_tx(sdata, sdata->u.mesh.mshcfg.element_ttl, mpath->dst, mpath->sn, WLAN_REASON_MESH_PATH_DEST_UNREACHABLE, bcast); } } rcu_read_unlock(); } static void mesh_path_free_rcu(struct mesh_table *tbl, struct mesh_path *mpath) { struct ieee80211_sub_if_data *sdata = mpath->sdata; spin_lock_bh(&mpath->state_lock); mpath->flags |= MESH_PATH_RESOLVING | MESH_PATH_DELETED; mesh_gate_del(tbl, mpath); spin_unlock_bh(&mpath->state_lock); timer_shutdown_sync(&mpath->timer); atomic_dec(&sdata->u.mesh.mpaths); atomic_dec(&tbl->entries); mesh_path_flush_pending(mpath); kfree_rcu(mpath, rcu); } static void __mesh_path_del(struct mesh_table *tbl, struct mesh_path *mpath) { hlist_del_rcu(&mpath->walk_list); rhashtable_remove_fast(&tbl->rhead, &mpath->rhash, mesh_rht_params); if (tbl == &mpath->sdata->u.mesh.mpp_paths) mesh_fast_tx_flush_addr(mpath->sdata, mpath->dst); else mesh_fast_tx_flush_mpath(mpath); mesh_path_free_rcu(tbl, mpath); } /** * mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches * * @sta: mesh peer to match * * RCU notes: this function is called when a mesh plink transitions from * PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that * allows path creation. This will happen before the sta can be freed (because * sta_info_destroy() calls this) so any reader in a rcu read block will be * protected against the plink disappearing. */ void mesh_path_flush_by_nexthop(struct sta_info *sta) { struct ieee80211_sub_if_data *sdata = sta->sdata; struct mesh_table *tbl = &sdata->u.mesh.mesh_paths; struct mesh_path *mpath; struct hlist_node *n; spin_lock_bh(&tbl->walk_lock); hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) { if (rcu_access_pointer(mpath->next_hop) == sta) __mesh_path_del(tbl, mpath); } spin_unlock_bh(&tbl->walk_lock); } static void mpp_flush_by_proxy(struct ieee80211_sub_if_data *sdata, const u8 *proxy) { struct mesh_table *tbl = &sdata->u.mesh.mpp_paths; struct mesh_path *mpath; struct hlist_node *n; spin_lock_bh(&tbl->walk_lock); hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) { if (ether_addr_equal(mpath->mpp, proxy)) __mesh_path_del(tbl, mpath); } spin_unlock_bh(&tbl->walk_lock); } static void table_flush_by_iface(struct mesh_table *tbl) { struct mesh_path *mpath; struct hlist_node *n; spin_lock_bh(&tbl->walk_lock); hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) { __mesh_path_del(tbl, mpath); } spin_unlock_bh(&tbl->walk_lock); } /** * mesh_path_flush_by_iface - Deletes all mesh paths associated with a given iface * * @sdata: interface data to match * * This function deletes both mesh paths as well as mesh portal paths. */ void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata) { table_flush_by_iface(&sdata->u.mesh.mesh_paths); table_flush_by_iface(&sdata->u.mesh.mpp_paths); } /** * table_path_del - delete a path from the mesh or mpp table * * @tbl: mesh or mpp path table * @sdata: local subif * @addr: dst address (ETH_ALEN length) * * Returns: 0 if successful */ static int table_path_del(struct mesh_table *tbl, struct ieee80211_sub_if_data *sdata, const u8 *addr) { struct mesh_path *mpath; spin_lock_bh(&tbl->walk_lock); mpath = rhashtable_lookup_fast(&tbl->rhead, addr, mesh_rht_params); if (!mpath) { spin_unlock_bh(&tbl->walk_lock); return -ENXIO; } __mesh_path_del(tbl, mpath); spin_unlock_bh(&tbl->walk_lock); return 0; } /** * mesh_path_del - delete a mesh path from the table * * @sdata: local subif * @addr: dst address (ETH_ALEN length) * * Returns: 0 if successful */ int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr) { int err; /* flush relevant mpp entries first */ mpp_flush_by_proxy(sdata, addr); err = table_path_del(&sdata->u.mesh.mesh_paths, sdata, addr); sdata->u.mesh.mesh_paths_generation++; return err; } /** * mesh_path_tx_pending - sends pending frames in a mesh path queue * * @mpath: mesh path to activate * * Locking: the state_lock of the mpath structure must NOT be held when calling * this function. */ void mesh_path_tx_pending(struct mesh_path *mpath) { if (mpath->flags & MESH_PATH_ACTIVE) ieee80211_add_pending_skbs(mpath->sdata->local, &mpath->frame_queue); } /** * mesh_path_send_to_gates - sends pending frames to all known mesh gates * * @mpath: mesh path whose queue will be emptied * * If there is only one gate, the frames are transferred from the failed mpath * queue to that gate's queue. If there are more than one gates, the frames * are copied from each gate to the next. After frames are copied, the * mpath queues are emptied onto the transmission queue. * * Returns: 0 on success, -EHOSTUNREACH */ int mesh_path_send_to_gates(struct mesh_path *mpath) { struct ieee80211_sub_if_data *sdata = mpath->sdata; struct mesh_table *tbl; struct mesh_path *from_mpath = mpath; struct mesh_path *gate; bool copy = false; tbl = &sdata->u.mesh.mesh_paths; rcu_read_lock(); hlist_for_each_entry_rcu(gate, &tbl->known_gates, gate_list) { if (gate->flags & MESH_PATH_ACTIVE) { mpath_dbg(sdata, "Forwarding to %pM\n", gate->dst); mesh_path_move_to_queue(gate, from_mpath, copy); from_mpath = gate; copy = true; } else { mpath_dbg(sdata, "Not forwarding to %pM (flags %#x)\n", gate->dst, gate->flags); } } hlist_for_each_entry_rcu(gate, &tbl->known_gates, gate_list) { mpath_dbg(sdata, "Sending to %pM\n", gate->dst); mesh_path_tx_pending(gate); } rcu_read_unlock(); return (from_mpath == mpath) ? -EHOSTUNREACH : 0; } /** * mesh_path_discard_frame - discard a frame whose path could not be resolved * * @sdata: network subif the frame was to be sent through * @skb: frame to discard * * Locking: the function must me called within a rcu_read_lock region */ void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) { ieee80211_free_txskb(&sdata->local->hw, skb); sdata->u.mesh.mshstats.dropped_frames_no_route++; } /** * mesh_path_flush_pending - free the pending queue of a mesh path * * @mpath: mesh path whose queue has to be freed * * Locking: the function must me called within a rcu_read_lock region */ void mesh_path_flush_pending(struct mesh_path *mpath) { struct ieee80211_sub_if_data *sdata = mpath->sdata; struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; struct mesh_preq_queue *preq, *tmp; struct sk_buff *skb; while ((skb = skb_dequeue(&mpath->frame_queue)) != NULL) mesh_path_discard_frame(mpath->sdata, skb); spin_lock_bh(&ifmsh->mesh_preq_queue_lock); list_for_each_entry_safe(preq, tmp, &ifmsh->preq_queue.list, list) { if (ether_addr_equal(mpath->dst, preq->dst)) { list_del(&preq->list); kfree(preq); --ifmsh->preq_queue_len; } } spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); } /** * mesh_path_fix_nexthop - force a specific next hop for a mesh path * * @mpath: the mesh path to modify * @next_hop: the next hop to force * * Locking: this function must be called holding mpath->state_lock */ void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop) { spin_lock_bh(&mpath->state_lock); mesh_path_assign_nexthop(mpath, next_hop); mpath->sn = 0xffff; mpath->metric = 0; mpath->hop_count = 0; mpath->exp_time = 0; mpath->flags = MESH_PATH_FIXED | MESH_PATH_SN_VALID; mesh_path_activate(mpath); mesh_fast_tx_flush_mpath(mpath); spin_unlock_bh(&mpath->state_lock); ewma_mesh_fail_avg_init(&next_hop->mesh->fail_avg); /* init it at a low value - 0 start is tricky */ ewma_mesh_fail_avg_add(&next_hop->mesh->fail_avg, 1); mesh_path_tx_pending(mpath); } void mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata) { mesh_table_init(&sdata->u.mesh.mesh_paths); mesh_table_init(&sdata->u.mesh.mpp_paths); mesh_fast_tx_init(sdata); } static void mesh_path_tbl_expire(struct ieee80211_sub_if_data *sdata, struct mesh_table *tbl) { struct mesh_path *mpath; struct hlist_node *n; spin_lock_bh(&tbl->walk_lock); hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) { if ((!(mpath->flags & MESH_PATH_RESOLVING)) && (!(mpath->flags & MESH_PATH_FIXED)) && time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE)) __mesh_path_del(tbl, mpath); } spin_unlock_bh(&tbl->walk_lock); } void mesh_path_expire(struct ieee80211_sub_if_data *sdata) { mesh_path_tbl_expire(sdata, &sdata->u.mesh.mesh_paths); mesh_path_tbl_expire(sdata, &sdata->u.mesh.mpp_paths); } void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata) { mesh_fast_tx_deinit(sdata); mesh_table_free(&sdata->u.mesh.mesh_paths); mesh_table_free(&sdata->u.mesh.mpp_paths); }