static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt, const u8 *perr_elem) { struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; struct mesh_path *mpath; u8 ttl; const u8 *ta, *target_addr; u32 target_sn; u16 target_rcode; ta = mgmt->sa; ttl = PERR_IE_TTL(perr_elem); if (ttl <= 1) { ifmsh->mshstats.dropped_frames_ttl++; return; } ttl--; target_addr = PERR_IE_TARGET_ADDR(perr_elem); target_sn = PERR_IE_TARGET_SN(perr_elem); target_rcode = PERR_IE_TARGET_RCODE(perr_elem); rcu_read_lock(); mpath = mesh_path_lookup(sdata, target_addr); if (mpath) { struct sta_info *sta; spin_lock_bh(&mpath->state_lock); sta = next_hop_deref_protected(mpath); if (mpath->flags & MESH_PATH_ACTIVE && ether_addr_equal(ta, sta->sta.addr) && !(mpath->flags & MESH_PATH_FIXED) && (!(mpath->flags & MESH_PATH_SN_VALID) || SN_GT(target_sn, mpath->sn) || target_sn == 0)) { mpath->flags &= ~MESH_PATH_ACTIVE; if (target_sn != 0) mpath->sn = target_sn; else mpath->sn += 1; spin_unlock_bh(&mpath->state_lock); if (!ifmsh->mshcfg.dot11MeshForwarding) goto endperr; mesh_path_error_tx(sdata, ttl, target_addr, target_sn, target_rcode, broadcast_addr); } else spin_unlock_bh(&mpath->state_lock); } endperr: rcu_read_unlock(); }
static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt, u8 *perr_elem) { struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; struct mesh_path *mpath; u8 ttl; u8 *ta, *target_addr; u32 target_sn; u16 target_rcode; ta = mgmt->sa; ttl = PERR_IE_TTL(perr_elem); if (ttl <= 1) { ifmsh->mshstats.dropped_frames_ttl++; return; } ttl--; target_addr = PERR_IE_TARGET_ADDR(perr_elem); target_sn = PERR_IE_TARGET_SN(perr_elem); target_rcode = PERR_IE_TARGET_RCODE(perr_elem); rcu_read_lock(); mpath = mesh_path_lookup(target_addr, sdata); if (mpath) { spin_lock_bh(&mpath->state_lock); if (mpath->flags & MESH_PATH_ACTIVE && memcmp(ta, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN) == 0 && (!(mpath->flags & MESH_PATH_SN_VALID) || SN_GT(target_sn, mpath->sn))) { mpath->flags &= ~MESH_PATH_ACTIVE; mpath->sn = target_sn; spin_unlock_bh(&mpath->state_lock); mesh_path_error_tx(ttl, target_addr, cpu_to_le32(target_sn), cpu_to_le16(target_rcode), broadcast_addr, sdata); } else spin_unlock_bh(&mpath->state_lock); } rcu_read_unlock(); }
/** * hwmp_route_info_get - Update routing info to originator and transmitter * * @sdata: local mesh subif * @mgmt: mesh management frame * @hwmp_ie: hwmp information element (PREP or PREQ) * @action: type of hwmp ie * * This function updates the path routing information to the originator and the * transmitter of a HWMP PREQ or PREP frame. * * Returns: metric to frame originator or 0 if the frame should not be further * processed * * Notes: this function is the only place (besides user-provided info) where * path routing information is updated. */ static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt, u8 *hwmp_ie, enum mpath_frame_type action) { struct ieee80211_local *local = sdata->local; struct mesh_path *mpath; struct sta_info *sta; bool fresh_info; u8 *orig_addr, *ta; u32 orig_sn, orig_metric; unsigned long orig_lifetime, exp_time; u32 last_hop_metric, new_metric; bool process = true; rcu_read_lock(); sta = sta_info_get(sdata, mgmt->sa); if (!sta) { rcu_read_unlock(); return 0; } last_hop_metric = airtime_link_metric_get(local, sta); /* Update and check originator routing info */ fresh_info = true; switch (action) { case MPATH_PREQ: orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); orig_sn = PREQ_IE_ORIG_SN(hwmp_ie); orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); orig_metric = PREQ_IE_METRIC(hwmp_ie); break; case MPATH_PREP: /* Originator here refers to the MP that was the target in the * Path Request. We divert from the nomenclature in the draft * so that we can easily use a single function to gather path * information from both PREQ and PREP frames. */ orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie); orig_sn = PREP_IE_TARGET_SN(hwmp_ie); orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); orig_metric = PREP_IE_METRIC(hwmp_ie); break; default: rcu_read_unlock(); return 0; } new_metric = orig_metric + last_hop_metric; if (new_metric < orig_metric) new_metric = MAX_METRIC; exp_time = TU_TO_EXP_TIME(orig_lifetime); if (ether_addr_equal(orig_addr, sdata->vif.addr)) { /* This MP is the originator, we are not interested in this * frame, except for updating transmitter's path info. */ process = false; fresh_info = false; } else { mpath = mesh_path_lookup(orig_addr, sdata); if (mpath) { spin_lock_bh(&mpath->state_lock); if (mpath->flags & MESH_PATH_FIXED) fresh_info = false; else if ((mpath->flags & MESH_PATH_ACTIVE) && (mpath->flags & MESH_PATH_SN_VALID)) { if (SN_GT(mpath->sn, orig_sn) || (mpath->sn == orig_sn && new_metric >= mpath->metric)) { process = false; fresh_info = false; } } } else { mesh_path_add(orig_addr, sdata); mpath = mesh_path_lookup(orig_addr, sdata); if (!mpath) { rcu_read_unlock(); return 0; } spin_lock_bh(&mpath->state_lock); } if (fresh_info) { mesh_path_assign_nexthop(mpath, sta); mpath->flags |= MESH_PATH_SN_VALID; mpath->metric = new_metric; mpath->sn = orig_sn; mpath->exp_time = time_after(mpath->exp_time, exp_time) ? mpath->exp_time : exp_time; mesh_path_activate(mpath); spin_unlock_bh(&mpath->state_lock); mesh_path_tx_pending(mpath); /* draft says preq_id should be saved to, but there does * not seem to be any use for it, skipping by now */ } else spin_unlock_bh(&mpath->state_lock); } /* Update and check transmitter routing info */ ta = mgmt->sa; if (ether_addr_equal(orig_addr, ta)) fresh_info = false; else { fresh_info = true; mpath = mesh_path_lookup(ta, sdata); if (mpath) { spin_lock_bh(&mpath->state_lock); if ((mpath->flags & MESH_PATH_FIXED) || ((mpath->flags & MESH_PATH_ACTIVE) && (last_hop_metric > mpath->metric))) fresh_info = false; } else { mesh_path_add(ta, sdata); mpath = mesh_path_lookup(ta, sdata); if (!mpath) { rcu_read_unlock(); return 0; } spin_lock_bh(&mpath->state_lock); } if (fresh_info) { mesh_path_assign_nexthop(mpath, sta); mpath->metric = last_hop_metric; mpath->exp_time = time_after(mpath->exp_time, exp_time) ? mpath->exp_time : exp_time; mesh_path_activate(mpath); spin_unlock_bh(&mpath->state_lock); mesh_path_tx_pending(mpath); } else spin_unlock_bh(&mpath->state_lock); } rcu_read_unlock(); return process ? new_metric : 0; }