| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright (c) 2008, 2009 open80211s Ltd. |
| * Copyright (C) 2019, 2021-2022 Intel Corporation |
| * Author: Luis Carlos Cobo <luisca@cozybit.com> |
| */ |
| |
| #include <linux/slab.h> |
| #include <linux/etherdevice.h> |
| #include <asm/unaligned.h> |
| #include "wme.h" |
| #include "mesh.h" |
| |
| #define TEST_FRAME_LEN 8192 |
| #define MAX_METRIC 0xffffffff |
| #define ARITH_SHIFT 8 |
| #define LINK_FAIL_THRESH 95 |
| |
| #define MAX_PREQ_QUEUE_LEN 64 |
| |
| static void mesh_queue_preq(struct mesh_path *, u8); |
| |
| static inline u32 u32_field_get(const u8 *preq_elem, int offset, bool ae) |
| { |
| if (ae) |
| offset += 6; |
| return get_unaligned_le32(preq_elem + offset); |
| } |
| |
| static inline u16 u16_field_get(const u8 *preq_elem, int offset, bool ae) |
| { |
| if (ae) |
| offset += 6; |
| return get_unaligned_le16(preq_elem + offset); |
| } |
| |
| /* HWMP IE processing macros */ |
| #define AE_F (1<<6) |
| #define AE_F_SET(x) (*x & AE_F) |
| #define PREQ_IE_FLAGS(x) (*(x)) |
| #define PREQ_IE_HOPCOUNT(x) (*(x + 1)) |
| #define PREQ_IE_TTL(x) (*(x + 2)) |
| #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0) |
| #define PREQ_IE_ORIG_ADDR(x) (x + 7) |
| #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0) |
| #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x)) |
| #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x)) |
| #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26)) |
| #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27) |
| #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x)) |
| |
| |
| #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x) |
| #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x) |
| #define PREP_IE_TTL(x) PREQ_IE_TTL(x) |
| #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21) |
| #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x)) |
| #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x)) |
| #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x)) |
| #define PREP_IE_TARGET_ADDR(x) (x + 3) |
| #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0) |
| |
| #define PERR_IE_TTL(x) (*(x)) |
| #define PERR_IE_TARGET_FLAGS(x) (*(x + 2)) |
| #define PERR_IE_TARGET_ADDR(x) (x + 3) |
| #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0) |
| #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0) |
| |
| #define MSEC_TO_TU(x) (x*1000/1024) |
| #define SN_GT(x, y) ((s32)(y - x) < 0) |
| #define SN_LT(x, y) ((s32)(x - y) < 0) |
| #define MAX_SANE_SN_DELTA 32 |
| |
| static inline u32 SN_DELTA(u32 x, u32 y) |
| { |
| return x >= y ? x - y : y - x; |
| } |
| |
| #define net_traversal_jiffies(s) \ |
| msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime) |
| #define default_lifetime(s) \ |
| MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout) |
| #define min_preq_int_jiff(s) \ |
| (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval)) |
| #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries) |
| #define disc_timeout_jiff(s) \ |
| msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout) |
| #define root_path_confirmation_jiffies(s) \ |
| msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval) |
| |
| enum mpath_frame_type { |
| MPATH_PREQ = 0, |
| MPATH_PREP, |
| MPATH_PERR, |
| MPATH_RANN |
| }; |
| |
| static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; |
| |
| static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags, |
| const u8 *orig_addr, u32 orig_sn, |
| u8 target_flags, const u8 *target, |
| u32 target_sn, const u8 *da, |
| u8 hop_count, u8 ttl, |
| u32 lifetime, u32 metric, u32 preq_id, |
| struct ieee80211_sub_if_data *sdata) |
| { |
| struct ieee80211_local *local = sdata->local; |
| struct sk_buff *skb; |
| struct ieee80211_mgmt *mgmt; |
| u8 *pos, ie_len; |
| int hdr_len = offsetofend(struct ieee80211_mgmt, |
| u.action.u.mesh_action); |
| |
| skb = dev_alloc_skb(local->tx_headroom + |
| hdr_len + |
| 2 + 37); /* max HWMP IE */ |
| if (!skb) |
| return -1; |
| skb_reserve(skb, local->tx_headroom); |
| mgmt = skb_put_zero(skb, hdr_len); |
| mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | |
| IEEE80211_STYPE_ACTION); |
| |
| memcpy(mgmt->da, da, ETH_ALEN); |
| memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); |
| /* BSSID == SA */ |
| memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); |
| mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; |
| mgmt->u.action.u.mesh_action.action_code = |
| WLAN_MESH_ACTION_HWMP_PATH_SELECTION; |
| |
| switch (action) { |
| case MPATH_PREQ: |
| mhwmp_dbg(sdata, "sending PREQ to %pM\n", target); |
| ie_len = 37; |
| pos = skb_put(skb, 2 + ie_len); |
| *pos++ = WLAN_EID_PREQ; |
| break; |
| case MPATH_PREP: |
| mhwmp_dbg(sdata, "sending PREP to %pM\n", orig_addr); |
| ie_len = 31; |
| pos = skb_put(skb, 2 + ie_len); |
| *pos++ = WLAN_EID_PREP; |
| break; |
| case MPATH_RANN: |
| mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr); |
| ie_len = sizeof(struct ieee80211_rann_ie); |
| pos = skb_put(skb, 2 + ie_len); |
| *pos++ = WLAN_EID_RANN; |
| break; |
| default: |
| kfree_skb(skb); |
| return -ENOTSUPP; |
| } |
| *pos++ = ie_len; |
| *pos++ = flags; |
| *pos++ = hop_count; |
| *pos++ = ttl; |
| if (action == MPATH_PREP) { |
| memcpy(pos, target, ETH_ALEN); |
| pos += ETH_ALEN; |
| put_unaligned_le32(target_sn, pos); |
| pos += 4; |
| } else { |
| if (action == MPATH_PREQ) { |
| put_unaligned_le32(preq_id, pos); |
| pos += 4; |
| } |
| memcpy(pos, orig_addr, ETH_ALEN); |
| pos += ETH_ALEN; |
| put_unaligned_le32(orig_sn, pos); |
| pos += 4; |
| } |
| put_unaligned_le32(lifetime, pos); /* interval for RANN */ |
| pos += 4; |
| put_unaligned_le32(metric, pos); |
| pos += 4; |
| if (action == MPATH_PREQ) { |
| *pos++ = 1; /* destination count */ |
| *pos++ = target_flags; |
| memcpy(pos, target, ETH_ALEN); |
| pos += ETH_ALEN; |
| put_unaligned_le32(target_sn, pos); |
| pos += 4; |
| } else if (action == MPATH_PREP) { |
| memcpy(pos, orig_addr, ETH_ALEN); |
| pos += ETH_ALEN; |
| put_unaligned_le32(orig_sn, pos); |
| pos += 4; |
| } |
| |
| ieee80211_tx_skb(sdata, skb); |
| return 0; |
| } |
| |
| |
| /* Headroom is not adjusted. Caller should ensure that skb has sufficient |
| * headroom in case the frame is encrypted. */ |
| static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata, |
| struct sk_buff *skb) |
| { |
| struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| |
| skb_reset_mac_header(skb); |
| skb_reset_network_header(skb); |
| skb_reset_transport_header(skb); |
| |
| /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */ |
| skb_set_queue_mapping(skb, IEEE80211_AC_VO); |
| skb->priority = 7; |
| |
| info->control.vif = &sdata->vif; |
| info->control.flags |= IEEE80211_TX_INTCFL_NEED_TXPROCESSING; |
| ieee80211_set_qos_hdr(sdata, skb); |
| ieee80211_mps_set_frame_flags(sdata, NULL, hdr); |
| } |
| |
| /** |
| * mesh_path_error_tx - Sends a PERR mesh management frame |
| * |
| * @ttl: allowed remaining hops |
| * @target: broken destination |
| * @target_sn: SN of the broken destination |
| * @target_rcode: reason code for this PERR |
| * @ra: node this frame is addressed to |
| * @sdata: local mesh subif |
| * |
| * Note: This function may be called with driver locks taken that the driver |
| * also acquires in the TX path. To avoid a deadlock we don't transmit the |
| * frame directly but add it to the pending queue instead. |
| */ |
| int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata, |
| u8 ttl, const u8 *target, u32 target_sn, |
| u16 target_rcode, const u8 *ra) |
| { |
| struct ieee80211_local *local = sdata->local; |
| struct sk_buff *skb; |
| struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| struct ieee80211_mgmt *mgmt; |
| u8 *pos, ie_len; |
| int hdr_len = offsetofend(struct ieee80211_mgmt, |
| u.action.u.mesh_action); |
| |
| if (time_before(jiffies, ifmsh->next_perr)) |
| return -EAGAIN; |
| |
| skb = dev_alloc_skb(local->tx_headroom + |
| IEEE80211_ENCRYPT_HEADROOM + |
| IEEE80211_ENCRYPT_TAILROOM + |
| hdr_len + |
| 2 + 15 /* PERR IE */); |
| if (!skb) |
| return -1; |
| skb_reserve(skb, local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM); |
| mgmt = skb_put_zero(skb, hdr_len); |
| mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | |
| IEEE80211_STYPE_ACTION); |
| |
| memcpy(mgmt->da, ra, ETH_ALEN); |
| memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); |
| /* BSSID == SA */ |
| memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); |
| mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; |
| mgmt->u.action.u.mesh_action.action_code = |
| WLAN_MESH_ACTION_HWMP_PATH_SELECTION; |
| ie_len = 15; |
| pos = skb_put(skb, 2 + ie_len); |
| *pos++ = WLAN_EID_PERR; |
| *pos++ = ie_len; |
| /* ttl */ |
| *pos++ = ttl; |
| /* number of destinations */ |
| *pos++ = 1; |
| /* Flags field has AE bit only as defined in |
| * sec 8.4.2.117 IEEE802.11-2012 |
| */ |
| *pos = 0; |
| pos++; |
| memcpy(pos, target, ETH_ALEN); |
| pos += ETH_ALEN; |
| put_unaligned_le32(target_sn, pos); |
| pos += 4; |
| put_unaligned_le16(target_rcode, pos); |
| |
| /* see note in function header */ |
| prepare_frame_for_deferred_tx(sdata, skb); |
| ifmsh->next_perr = TU_TO_EXP_TIME( |
| ifmsh->mshcfg.dot11MeshHWMPperrMinInterval); |
| ieee80211_add_pending_skb(local, skb); |
| return 0; |
| } |
| |
| void ieee80211s_update_metric(struct ieee80211_local *local, |
| struct sta_info *sta, |
| struct ieee80211_tx_status *st) |
| { |
| struct ieee80211_tx_info *txinfo = st->info; |
| int failed; |
| struct rate_info rinfo; |
| |
| failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK); |
| |
| /* moving average, scaled to 100. |
| * feed failure as 100 and success as 0 |
| */ |
| ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, failed * 100); |
| if (ewma_mesh_fail_avg_read(&sta->mesh->fail_avg) > |
| LINK_FAIL_THRESH) |
| mesh_plink_broken(sta); |
| |
| /* use rate info set by the driver directly if present */ |
| if (st->n_rates) |
| rinfo = sta->deflink.tx_stats.last_rate_info; |
| else |
| sta_set_rate_info_tx(sta, &sta->deflink.tx_stats.last_rate, &rinfo); |
| |
| ewma_mesh_tx_rate_avg_add(&sta->mesh->tx_rate_avg, |
| cfg80211_calculate_bitrate(&rinfo)); |
| } |
| |
| u32 airtime_link_metric_get(struct ieee80211_local *local, |
| struct sta_info *sta) |
| { |
| /* This should be adjusted for each device */ |
| int device_constant = 1 << ARITH_SHIFT; |
| int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; |
| int s_unit = 1 << ARITH_SHIFT; |
| int rate, err; |
| u32 tx_time, estimated_retx; |
| u64 result; |
| unsigned long fail_avg = |
| ewma_mesh_fail_avg_read(&sta->mesh->fail_avg); |
| |
| if (sta->mesh->plink_state != NL80211_PLINK_ESTAB) |
| return MAX_METRIC; |
| |
| /* Try to get rate based on HW/SW RC algorithm. |
| * Rate is returned in units of Kbps, correct this |
| * to comply with airtime calculation units |
| * Round up in case we get rate < 100Kbps |
| */ |
| rate = DIV_ROUND_UP(sta_get_expected_throughput(sta), 100); |
| |
| if (rate) { |
| err = 0; |
| } else { |
| if (fail_avg > LINK_FAIL_THRESH) |
| return MAX_METRIC; |
| |
| rate = ewma_mesh_tx_rate_avg_read(&sta->mesh->tx_rate_avg); |
| if (WARN_ON(!rate)) |
| return MAX_METRIC; |
| |
| err = (fail_avg << ARITH_SHIFT) / 100; |
| } |
| |
| /* bitrate is in units of 100 Kbps, while we need rate in units of |
| * 1Mbps. This will be corrected on tx_time computation. |
| */ |
| tx_time = (device_constant + 10 * test_frame_len / rate); |
| estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); |
| result = ((u64)tx_time * estimated_retx) >> (2 * ARITH_SHIFT); |
| return (u32)result; |
| } |
| |
| /** |
| * 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, |
| const 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; |
| const u8 *orig_addr, *ta; |
| u32 orig_sn, orig_metric; |
| unsigned long orig_lifetime, exp_time; |
| u32 last_hop_metric, new_metric; |
| bool process = true; |
| u8 hopcount; |
| |
| 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); |
| hopcount = PREQ_IE_HOPCOUNT(hwmp_ie) + 1; |
| 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); |
| hopcount = PREP_IE_HOPCOUNT(hwmp_ie) + 1; |
| 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(sdata, orig_addr); |
| 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 && |
| (rcu_access_pointer(mpath->next_hop) != |
| sta ? |
| mult_frac(new_metric, 10, 9) : |
| new_metric) >= mpath->metric)) { |
| process = false; |
| fresh_info = false; |
| } |
| } else if (!(mpath->flags & MESH_PATH_ACTIVE)) { |
| bool have_sn, newer_sn, bounced; |
| |
| have_sn = mpath->flags & MESH_PATH_SN_VALID; |
| newer_sn = have_sn && SN_GT(orig_sn, mpath->sn); |
| bounced = have_sn && |
| (SN_DELTA(orig_sn, mpath->sn) > |
| MAX_SANE_SN_DELTA); |
| |
| if (!have_sn || newer_sn) { |
| /* if SN is newer than what we had |
| * then we can take it */; |
| } else if (bounced) { |
| /* if SN is way different than what |
| * we had then assume the other side |
| * rebooted or restarted */; |
| } else { |
| process = false; |
| fresh_info = false; |
| } |
| } |
| } else { |
| mpath = mesh_path_add(sdata, orig_addr); |
| if (IS_ERR(mpath)) { |
| rcu_read_unlock(); |
| return 0; |
| } |
| spin_lock_bh(&mpath->state_lock); |
| } |
| |
| if (fresh_info) { |
| if (rcu_access_pointer(mpath->next_hop) != sta) |
| mpath->path_change_count++; |
| 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; |
| mpath->hop_count = hopcount; |
| mesh_path_activate(mpath); |
| spin_unlock_bh(&mpath->state_lock); |
| ewma_mesh_fail_avg_init(&sta->mesh->fail_avg); |
| /* init it at a low value - 0 start is tricky */ |
| ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1); |
| 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(sdata, ta); |
| if (mpath) { |
| spin_lock_bh(&mpath->state_lock); |
| if ((mpath->flags & MESH_PATH_FIXED) || |
| ((mpath->flags & MESH_PATH_ACTIVE) && |
| ((rcu_access_pointer(mpath->next_hop) != sta ? |
| mult_frac(last_hop_metric, 10, 9) : |
| last_hop_metric) > mpath->metric))) |
| fresh_info = false; |
| } else { |
| mpath = mesh_path_add(sdata, ta); |
| if (IS_ERR(mpath)) { |
| rcu_read_unlock(); |
| return 0; |
| } |
| spin_lock_bh(&mpath->state_lock); |
| } |
| |
| if (fresh_info) { |
| if (rcu_access_pointer(mpath->next_hop) != sta) |
| mpath->path_change_count++; |
| 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; |
| mpath->hop_count = 1; |
| mesh_path_activate(mpath); |
| spin_unlock_bh(&mpath->state_lock); |
| ewma_mesh_fail_avg_init(&sta->mesh->fail_avg); |
| /* init it at a low value - 0 start is tricky */ |
| ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1); |
| mesh_path_tx_pending(mpath); |
| } else |
| spin_unlock_bh(&mpath->state_lock); |
| } |
| |
| rcu_read_unlock(); |
| |
| return process ? new_metric : 0; |
| } |
| |
| static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata, |
| struct ieee80211_mgmt *mgmt, |
| const u8 *preq_elem, u32 orig_metric) |
| { |
| struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| struct mesh_path *mpath = NULL; |
| const u8 *target_addr, *orig_addr; |
| const u8 *da; |
| u8 target_flags, ttl, flags; |
| u32 orig_sn, target_sn, lifetime, target_metric = 0; |
| bool reply = false; |
| bool forward = true; |
| bool root_is_gate; |
| |
| /* Update target SN, if present */ |
| target_addr = PREQ_IE_TARGET_ADDR(preq_elem); |
| orig_addr = PREQ_IE_ORIG_ADDR(preq_elem); |
| target_sn = PREQ_IE_TARGET_SN(preq_elem); |
| orig_sn = PREQ_IE_ORIG_SN(preq_elem); |
| target_flags = PREQ_IE_TARGET_F(preq_elem); |
| /* Proactive PREQ gate announcements */ |
| flags = PREQ_IE_FLAGS(preq_elem); |
| root_is_gate = !!(flags & RANN_FLAG_IS_GATE); |
| |
| mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr); |
| |
| if (ether_addr_equal(target_addr, sdata->vif.addr)) { |
| mhwmp_dbg(sdata, "PREQ is for us\n"); |
| forward = false; |
| reply = true; |
| target_metric = 0; |
| |
| if (SN_GT(target_sn, ifmsh->sn)) |
| ifmsh->sn = target_sn; |
| |
| if (time_after(jiffies, ifmsh->last_sn_update + |
| net_traversal_jiffies(sdata)) || |
| time_before(jiffies, ifmsh->last_sn_update)) { |
| ++ifmsh->sn; |
| ifmsh->last_sn_update = jiffies; |
| } |
| target_sn = ifmsh->sn; |
| } else if (is_broadcast_ether_addr(target_addr) && |
| (target_flags & IEEE80211_PREQ_TO_FLAG)) { |
| rcu_read_lock(); |
| mpath = mesh_path_lookup(sdata, orig_addr); |
| if (mpath) { |
| if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { |
| reply = true; |
| target_addr = sdata->vif.addr; |
| target_sn = ++ifmsh->sn; |
| target_metric = 0; |
| ifmsh->last_sn_update = jiffies; |
| } |
| if (root_is_gate) |
| mesh_path_add_gate(mpath); |
| } |
| rcu_read_unlock(); |
| } else { |
| rcu_read_lock(); |
| mpath = mesh_path_lookup(sdata, target_addr); |
| if (mpath) { |
| if ((!(mpath->flags & MESH_PATH_SN_VALID)) || |
| SN_LT(mpath->sn, target_sn)) { |
| mpath->sn = target_sn; |
| mpath->flags |= MESH_PATH_SN_VALID; |
| } else if ((!(target_flags & IEEE80211_PREQ_TO_FLAG)) && |
| (mpath->flags & MESH_PATH_ACTIVE)) { |
| reply = true; |
| target_metric = mpath->metric; |
| target_sn = mpath->sn; |
| /* Case E2 of sec 13.10.9.3 IEEE 802.11-2012*/ |
| target_flags |= IEEE80211_PREQ_TO_FLAG; |
| } |
| } |
| rcu_read_unlock(); |
| } |
| |
| if (reply) { |
| lifetime = PREQ_IE_LIFETIME(preq_elem); |
| ttl = ifmsh->mshcfg.element_ttl; |
| if (ttl != 0) { |
| mhwmp_dbg(sdata, "replying to the PREQ\n"); |
| mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr, |
| orig_sn, 0, target_addr, |
| target_sn, mgmt->sa, 0, ttl, |
| lifetime, target_metric, 0, |
| sdata); |
| } else { |
| ifmsh->mshstats.dropped_frames_ttl++; |
| } |
| } |
| |
| if (forward && ifmsh->mshcfg.dot11MeshForwarding) { |
| u32 preq_id; |
| u8 hopcount; |
| |
| ttl = PREQ_IE_TTL(preq_elem); |
| lifetime = PREQ_IE_LIFETIME(preq_elem); |
| if (ttl <= 1) { |
| ifmsh->mshstats.dropped_frames_ttl++; |
| return; |
| } |
| mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr); |
| --ttl; |
| preq_id = PREQ_IE_PREQ_ID(preq_elem); |
| hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; |
| da = (mpath && mpath->is_root) ? |
| mpath->rann_snd_addr : broadcast_addr; |
| |
| if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { |
| target_addr = PREQ_IE_TARGET_ADDR(preq_elem); |
| target_sn = PREQ_IE_TARGET_SN(preq_elem); |
| } |
| |
| mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, |
| orig_sn, target_flags, target_addr, |
| target_sn, da, hopcount, ttl, lifetime, |
| orig_metric, preq_id, sdata); |
| if (!is_multicast_ether_addr(da)) |
| ifmsh->mshstats.fwded_unicast++; |
| else |
| ifmsh->mshstats.fwded_mcast++; |
| ifmsh->mshstats.fwded_frames++; |
| } |
| } |
| |
| |
| static inline struct sta_info * |
| next_hop_deref_protected(struct mesh_path *mpath) |
| { |
| return rcu_dereference_protected(mpath->next_hop, |
| lockdep_is_held(&mpath->state_lock)); |
| } |
| |
| |
| static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata, |
| struct ieee80211_mgmt *mgmt, |
| const u8 *prep_elem, u32 metric) |
| { |
| struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| struct mesh_path *mpath; |
| const u8 *target_addr, *orig_addr; |
| u8 ttl, hopcount, flags; |
| u8 next_hop[ETH_ALEN]; |
| u32 target_sn, orig_sn, lifetime; |
| |
| mhwmp_dbg(sdata, "received PREP from %pM\n", |
| PREP_IE_TARGET_ADDR(prep_elem)); |
| |
| orig_addr = PREP_IE_ORIG_ADDR(prep_elem); |
| if (ether_addr_equal(orig_addr, sdata->vif.addr)) |
| /* destination, no forwarding required */ |
| return; |
| |
| if (!ifmsh->mshcfg.dot11MeshForwarding) |
| return; |
| |
| ttl = PREP_IE_TTL(prep_elem); |
| if (ttl <= 1) { |
| sdata->u.mesh.mshstats.dropped_frames_ttl++; |
| return; |
| } |
| |
| rcu_read_lock(); |
| mpath = mesh_path_lookup(sdata, orig_addr); |
| if (mpath) |
| spin_lock_bh(&mpath->state_lock); |
| else |
| goto fail; |
| if (!(mpath->flags & MESH_PATH_ACTIVE)) { |
| spin_unlock_bh(&mpath->state_lock); |
| goto fail; |
| } |
| memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN); |
| spin_unlock_bh(&mpath->state_lock); |
| --ttl; |
| flags = PREP_IE_FLAGS(prep_elem); |
| lifetime = PREP_IE_LIFETIME(prep_elem); |
| hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1; |
| target_addr = PREP_IE_TARGET_ADDR(prep_elem); |
| target_sn = PREP_IE_TARGET_SN(prep_elem); |
| orig_sn = PREP_IE_ORIG_SN(prep_elem); |
| |
| mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, orig_sn, 0, |
| target_addr, target_sn, next_hop, hopcount, |
| ttl, lifetime, metric, 0, sdata); |
| rcu_read_unlock(); |
| |
| sdata->u.mesh.mshstats.fwded_unicast++; |
| sdata->u.mesh.mshstats.fwded_frames++; |
| return; |
| |
| fail: |
| rcu_read_unlock(); |
| sdata->u.mesh.mshstats.dropped_frames_no_route++; |
| } |
| |
| 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_rann_frame_process(struct ieee80211_sub_if_data *sdata, |
| struct ieee80211_mgmt *mgmt, |
| const struct ieee80211_rann_ie *rann) |
| { |
| struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| struct ieee80211_local *local = sdata->local; |
| struct sta_info *sta; |
| struct mesh_path *mpath; |
| u8 ttl, flags, hopcount; |
| const u8 *orig_addr; |
| u32 orig_sn, new_metric, orig_metric, last_hop_metric, interval; |
| bool root_is_gate; |
| |
| ttl = rann->rann_ttl; |
| flags = rann->rann_flags; |
| root_is_gate = !!(flags & RANN_FLAG_IS_GATE); |
| orig_addr = rann->rann_addr; |
| orig_sn = le32_to_cpu(rann->rann_seq); |
| interval = le32_to_cpu(rann->rann_interval); |
| hopcount = rann->rann_hopcount; |
| hopcount++; |
| orig_metric = le32_to_cpu(rann->rann_metric); |
| |
| /* Ignore our own RANNs */ |
| if (ether_addr_equal(orig_addr, sdata->vif.addr)) |
| return; |
| |
| mhwmp_dbg(sdata, |
| "received RANN from %pM via neighbour %pM (is_gate=%d)\n", |
| orig_addr, mgmt->sa, root_is_gate); |
| |
| rcu_read_lock(); |
| sta = sta_info_get(sdata, mgmt->sa); |
| if (!sta) { |
| rcu_read_unlock(); |
| return; |
| } |
| |
| last_hop_metric = airtime_link_metric_get(local, sta); |
| new_metric = orig_metric + last_hop_metric; |
| if (new_metric < orig_metric) |
| new_metric = MAX_METRIC; |
| |
| mpath = mesh_path_lookup(sdata, orig_addr); |
| if (!mpath) { |
| mpath = mesh_path_add(sdata, orig_addr); |
| if (IS_ERR(mpath)) { |
| rcu_read_unlock(); |
| sdata->u.mesh.mshstats.dropped_frames_no_route++; |
| return; |
| } |
| } |
| |
| if (!(SN_LT(mpath->sn, orig_sn)) && |
| !(mpath->sn == orig_sn && new_metric < mpath->rann_metric)) { |
| rcu_read_unlock(); |
| return; |
| } |
| |
| if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) || |
| (time_after(jiffies, mpath->last_preq_to_root + |
| root_path_confirmation_jiffies(sdata)) || |
| time_before(jiffies, mpath->last_preq_to_root))) && |
| !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) { |
| mhwmp_dbg(sdata, |
| "time to refresh root mpath %pM\n", |
| orig_addr); |
| mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); |
| mpath->last_preq_to_root = jiffies; |
| } |
| |
| mpath->sn = orig_sn; |
| mpath->rann_metric = new_metric; |
| mpath->is_root = true; |
| /* Recording RANNs sender address to send individually |
| * addressed PREQs destined for root mesh STA */ |
| memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN); |
| |
| if (root_is_gate) |
| mesh_path_add_gate(mpath); |
| |
| if (ttl <= 1) { |
| ifmsh->mshstats.dropped_frames_ttl++; |
| rcu_read_unlock(); |
| return; |
| } |
| ttl--; |
| |
| if (ifmsh->mshcfg.dot11MeshForwarding) { |
| mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr, |
| orig_sn, 0, NULL, 0, broadcast_addr, |
| hopcount, ttl, interval, |
| new_metric, 0, sdata); |
| } |
| |
| rcu_read_unlock(); |
| } |
| |
| |
| void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, |
| struct ieee80211_mgmt *mgmt, size_t len) |
| { |
| struct ieee802_11_elems *elems; |
| size_t baselen; |
| u32 path_metric; |
| struct sta_info *sta; |
| |
| /* need action_code */ |
| if (len < IEEE80211_MIN_ACTION_SIZE + 1) |
| return; |
| |
| rcu_read_lock(); |
| sta = sta_info_get(sdata, mgmt->sa); |
| if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) { |
| rcu_read_unlock(); |
| return; |
| } |
| rcu_read_unlock(); |
| |
| baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; |
| elems = ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, |
| len - baselen, false, NULL); |
| if (!elems) |
| return; |
| |
| if (elems->preq) { |
| if (elems->preq_len != 37) |
| /* Right now we support just 1 destination and no AE */ |
| goto free; |
| path_metric = hwmp_route_info_get(sdata, mgmt, elems->preq, |
| MPATH_PREQ); |
| if (path_metric) |
| hwmp_preq_frame_process(sdata, mgmt, elems->preq, |
| path_metric); |
| } |
| if (elems->prep) { |
| if (elems->prep_len != 31) |
| /* Right now we support no AE */ |
| goto free; |
| path_metric = hwmp_route_info_get(sdata, mgmt, elems->prep, |
| MPATH_PREP); |
| if (path_metric) |
| hwmp_prep_frame_process(sdata, mgmt, elems->prep, |
| path_metric); |
| } |
| if (elems->perr) { |
| if (elems->perr_len != 15) |
| /* Right now we support only one destination per PERR */ |
| goto free; |
| hwmp_perr_frame_process(sdata, mgmt, elems->perr); |
| } |
| if (elems->rann) |
| hwmp_rann_frame_process(sdata, mgmt, elems->rann); |
| free: |
| kfree(elems); |
| } |
| |
| /** |
| * mesh_queue_preq - queue a PREQ to a given destination |
| * |
| * @mpath: mesh path to discover |
| * @flags: special attributes of the PREQ to be sent |
| * |
| * Locking: the function must be called from within a rcu read lock block. |
| * |
| */ |
| static void mesh_queue_preq(struct mesh_path *mpath, u8 flags) |
| { |
| struct ieee80211_sub_if_data *sdata = mpath->sdata; |
| struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| struct mesh_preq_queue *preq_node; |
| |
| preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC); |
| if (!preq_node) { |
| mhwmp_dbg(sdata, "could not allocate PREQ node\n"); |
| return; |
| } |
| |
| spin_lock_bh(&ifmsh->mesh_preq_queue_lock); |
| if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) { |
| spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); |
| kfree(preq_node); |
| if (printk_ratelimit()) |
| mhwmp_dbg(sdata, "PREQ node queue full\n"); |
| return; |
| } |
| |
| spin_lock(&mpath->state_lock); |
| if (mpath->flags & MESH_PATH_REQ_QUEUED) { |
| spin_unlock(&mpath->state_lock); |
| spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); |
| kfree(preq_node); |
| return; |
| } |
| |
| memcpy(preq_node->dst, mpath->dst, ETH_ALEN); |
| preq_node->flags = flags; |
| |
| mpath->flags |= MESH_PATH_REQ_QUEUED; |
| spin_unlock(&mpath->state_lock); |
| |
| list_add_tail(&preq_node->list, &ifmsh->preq_queue.list); |
| ++ifmsh->preq_queue_len; |
| spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); |
| |
| if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata))) |
| ieee80211_queue_work(&sdata->local->hw, &sdata->work); |
| |
| else if (time_before(jiffies, ifmsh->last_preq)) { |
| /* avoid long wait if did not send preqs for a long time |
| * and jiffies wrapped around |
| */ |
| ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1; |
| ieee80211_queue_work(&sdata->local->hw, &sdata->work); |
| } else |
| mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq + |
| min_preq_int_jiff(sdata)); |
| } |
| |
| /** |
| * mesh_path_start_discovery - launch a path discovery from the PREQ queue |
| * |
| * @sdata: local mesh subif |
| */ |
| void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata) |
| { |
| struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| struct mesh_preq_queue *preq_node; |
| struct mesh_path *mpath; |
| u8 ttl, target_flags = 0; |
| const u8 *da; |
| u32 lifetime; |
| |
| spin_lock_bh(&ifmsh->mesh_preq_queue_lock); |
| if (!ifmsh->preq_queue_len || |
| time_before(jiffies, ifmsh->last_preq + |
| min_preq_int_jiff(sdata))) { |
| spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); |
| return; |
| } |
| |
| preq_node = list_first_entry(&ifmsh->preq_queue.list, |
| struct mesh_preq_queue, list); |
| list_del(&preq_node->list); |
| --ifmsh->preq_queue_len; |
| spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); |
| |
| rcu_read_lock(); |
| mpath = mesh_path_lookup(sdata, preq_node->dst); |
| if (!mpath) |
| goto enddiscovery; |
| |
| spin_lock_bh(&mpath->state_lock); |
| if (mpath->flags & (MESH_PATH_DELETED | MESH_PATH_FIXED)) { |
| spin_unlock_bh(&mpath->state_lock); |
| goto enddiscovery; |
| } |
| mpath->flags &= ~MESH_PATH_REQ_QUEUED; |
| if (preq_node->flags & PREQ_Q_F_START) { |
| if (mpath->flags & MESH_PATH_RESOLVING) { |
| spin_unlock_bh(&mpath->state_lock); |
| goto enddiscovery; |
| } else { |
| mpath->flags &= ~MESH_PATH_RESOLVED; |
| mpath->flags |= MESH_PATH_RESOLVING; |
| mpath->discovery_retries = 0; |
| mpath->discovery_timeout = disc_timeout_jiff(sdata); |
| } |
| } else if (!(mpath->flags & MESH_PATH_RESOLVING) || |
| mpath->flags & MESH_PATH_RESOLVED) { |
| mpath->flags &= ~MESH_PATH_RESOLVING; |
| spin_unlock_bh(&mpath->state_lock); |
| goto enddiscovery; |
| } |
| |
| ifmsh->last_preq = jiffies; |
| |
| if (time_after(jiffies, ifmsh->last_sn_update + |
| net_traversal_jiffies(sdata)) || |
| time_before(jiffies, ifmsh->last_sn_update)) { |
| ++ifmsh->sn; |
| sdata->u.mesh.last_sn_update = jiffies; |
| } |
| lifetime = default_lifetime(sdata); |
| ttl = sdata->u.mesh.mshcfg.element_ttl; |
| if (ttl == 0) { |
| sdata->u.mesh.mshstats.dropped_frames_ttl++; |
| spin_unlock_bh(&mpath->state_lock); |
| goto enddiscovery; |
| } |
| |
| if (preq_node->flags & PREQ_Q_F_REFRESH) |
| target_flags |= IEEE80211_PREQ_TO_FLAG; |
| else |
| target_flags &= ~IEEE80211_PREQ_TO_FLAG; |
| |
| spin_unlock_bh(&mpath->state_lock); |
| da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr; |
| mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, ifmsh->sn, |
| target_flags, mpath->dst, mpath->sn, da, 0, |
| ttl, lifetime, 0, ifmsh->preq_id++, sdata); |
| |
| spin_lock_bh(&mpath->state_lock); |
| if (!(mpath->flags & MESH_PATH_DELETED)) |
| mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); |
| spin_unlock_bh(&mpath->state_lock); |
| |
| enddiscovery: |
| rcu_read_unlock(); |
| kfree(preq_node); |
| } |
| |
| /** |
| * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery |
| * |
| * @skb: 802.11 frame to be sent |
| * @sdata: network subif the frame will be sent through |
| * |
| * Lookup next hop for given skb and start path discovery if no |
| * forwarding information is found. |
| * |
| * Returns: 0 if the next hop was found and -ENOENT if the frame was queued. |
| * skb is freed here if no mpath could be allocated. |
| */ |
| int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata, |
| struct sk_buff *skb) |
| { |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
| struct mesh_path *mpath; |
| struct sk_buff *skb_to_free = NULL; |
| u8 *target_addr = hdr->addr3; |
| |
| /* Nulls are only sent to peers for PS and should be pre-addressed */ |
| if (ieee80211_is_qos_nullfunc(hdr->frame_control)) |
| return 0; |
| |
| /* Allow injected packets to bypass mesh routing */ |
| if (info->control.flags & IEEE80211_TX_CTRL_SKIP_MPATH_LOOKUP) |
| return 0; |
| |
| if (!mesh_nexthop_lookup(sdata, skb)) |
| return 0; |
| |
| /* no nexthop found, start resolving */ |
| mpath = mesh_path_lookup(sdata, target_addr); |
| if (!mpath) { |
| mpath = mesh_path_add(sdata, target_addr); |
| if (IS_ERR(mpath)) { |
| mesh_path_discard_frame(sdata, skb); |
| return PTR_ERR(mpath); |
| } |
| } |
| |
| if (!(mpath->flags & MESH_PATH_RESOLVING) && |
| mesh_path_sel_is_hwmp(sdata)) |
| mesh_queue_preq(mpath, PREQ_Q_F_START); |
| |
| if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN) |
| skb_to_free = skb_dequeue(&mpath->frame_queue); |
| |
| info->control.flags |= IEEE80211_TX_INTCFL_NEED_TXPROCESSING; |
| ieee80211_set_qos_hdr(sdata, skb); |
| skb_queue_tail(&mpath->frame_queue, skb); |
| if (skb_to_free) |
| mesh_path_discard_frame(sdata, skb_to_free); |
| |
| return -ENOENT; |
| } |
| |
| /** |
| * mesh_nexthop_lookup_nolearn - try to set next hop without path discovery |
| * @skb: 802.11 frame to be sent |
| * @sdata: network subif the frame will be sent through |
| * |
| * Check if the meshDA (addr3) of a unicast frame is a direct neighbor. |
| * And if so, set the RA (addr1) to it to transmit to this node directly, |
| * avoiding PREQ/PREP path discovery. |
| * |
| * Returns: 0 if the next hop was found and -ENOENT otherwise. |
| */ |
| static int mesh_nexthop_lookup_nolearn(struct ieee80211_sub_if_data *sdata, |
| struct sk_buff *skb) |
| { |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; |
| struct sta_info *sta; |
| |
| if (is_multicast_ether_addr(hdr->addr1)) |
| return -ENOENT; |
| |
| rcu_read_lock(); |
| sta = sta_info_get(sdata, hdr->addr3); |
| |
| if (!sta || sta->mesh->plink_state != NL80211_PLINK_ESTAB) { |
| rcu_read_unlock(); |
| return -ENOENT; |
| } |
| rcu_read_unlock(); |
| |
| memcpy(hdr->addr1, hdr->addr3, ETH_ALEN); |
| memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); |
| return 0; |
| } |
| |
| /** |
| * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling |
| * this function is considered "using" the associated mpath, so preempt a path |
| * refresh if this mpath expires soon. |
| * |
| * @skb: 802.11 frame to be sent |
| * @sdata: network subif the frame will be sent through |
| * |
| * Returns: 0 if the next hop was found. Nonzero otherwise. |
| */ |
| int mesh_nexthop_lookup(struct ieee80211_sub_if_data *sdata, |
| struct sk_buff *skb) |
| { |
| struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| struct mesh_path *mpath; |
| struct sta_info *next_hop; |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| u8 *target_addr = hdr->addr3; |
| |
| if (ifmsh->mshcfg.dot11MeshNolearn && |
| !mesh_nexthop_lookup_nolearn(sdata, skb)) |
| return 0; |
| |
| mpath = mesh_path_lookup(sdata, target_addr); |
| if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE)) |
| return -ENOENT; |
| |
| if (time_after(jiffies, |
| mpath->exp_time - |
| msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) && |
| ether_addr_equal(sdata->vif.addr, hdr->addr4) && |
| !(mpath->flags & MESH_PATH_RESOLVING) && |
| !(mpath->flags & MESH_PATH_FIXED)) |
| mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); |
| |
| next_hop = rcu_dereference(mpath->next_hop); |
| if (next_hop) { |
| memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN); |
| memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); |
| ieee80211_mps_set_frame_flags(sdata, next_hop, hdr); |
| return 0; |
| } |
| |
| return -ENOENT; |
| } |
| |
| void mesh_path_timer(struct timer_list *t) |
| { |
| struct mesh_path *mpath = from_timer(mpath, t, timer); |
| struct ieee80211_sub_if_data *sdata = mpath->sdata; |
| int ret; |
| |
| if (sdata->local->quiescing) |
| return; |
| |
| spin_lock_bh(&mpath->state_lock); |
| if (mpath->flags & MESH_PATH_RESOLVED || |
| (!(mpath->flags & MESH_PATH_RESOLVING))) { |
| mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED); |
| spin_unlock_bh(&mpath->state_lock); |
| } else if (mpath->discovery_retries < max_preq_retries(sdata)) { |
| ++mpath->discovery_retries; |
| mpath->discovery_timeout *= 2; |
| mpath->flags &= ~MESH_PATH_REQ_QUEUED; |
| spin_unlock_bh(&mpath->state_lock); |
| mesh_queue_preq(mpath, 0); |
| } else { |
| mpath->flags &= ~(MESH_PATH_RESOLVING | |
| MESH_PATH_RESOLVED | |
| MESH_PATH_REQ_QUEUED); |
| mpath->exp_time = jiffies; |
| spin_unlock_bh(&mpath->state_lock); |
| if (!mpath->is_gate && mesh_gate_num(sdata) > 0) { |
| ret = mesh_path_send_to_gates(mpath); |
| if (ret) |
| mhwmp_dbg(sdata, "no gate was reachable\n"); |
| } else |
| mesh_path_flush_pending(mpath); |
| } |
| } |
| |
| void mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata) |
| { |
| struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval; |
| u8 flags, target_flags = 0; |
| |
| flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol) |
| ? RANN_FLAG_IS_GATE : 0; |
| |
| switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) { |
| case IEEE80211_PROACTIVE_RANN: |
| mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr, |
| ++ifmsh->sn, 0, NULL, 0, broadcast_addr, |
| 0, ifmsh->mshcfg.element_ttl, |
| interval, 0, 0, sdata); |
| break; |
| case IEEE80211_PROACTIVE_PREQ_WITH_PREP: |
| flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG; |
| fallthrough; |
| case IEEE80211_PROACTIVE_PREQ_NO_PREP: |
| interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout; |
| target_flags |= IEEE80211_PREQ_TO_FLAG | |
| IEEE80211_PREQ_USN_FLAG; |
| mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr, |
| ++ifmsh->sn, target_flags, |
| (u8 *) broadcast_addr, 0, broadcast_addr, |
| 0, ifmsh->mshcfg.element_ttl, interval, |
| 0, ifmsh->preq_id++, sdata); |
| break; |
| default: |
| mhwmp_dbg(sdata, "Proactive mechanism not supported\n"); |
| return; |
| } |
| } |