| /* |
| * Copyright (c) 2008, 2009 open80211s Ltd. |
| * Author: Luis Carlos Cobo <luisca@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 "mesh.h" |
| |
| #ifdef CONFIG_MAC80211_VERBOSE_MHWMP_DEBUG |
| #define mhwmp_dbg(fmt, args...) printk(KERN_DEBUG "Mesh HWMP: " fmt, ##args) |
| #else |
| #define mhwmp_dbg(fmt, args...) do { (void)(0); } while (0) |
| #endif |
| |
| #define TEST_FRAME_LEN 8192 |
| #define MAX_METRIC 0xffffffff |
| #define ARITH_SHIFT 8 |
| |
| /* Number of frames buffered per destination for unresolved destinations */ |
| #define MESH_FRAME_QUEUE_LEN 10 |
| #define MAX_PREQ_QUEUE_LEN 64 |
| |
| /* Destination only */ |
| #define MP_F_DO 0x1 |
| /* Reply and forward */ |
| #define MP_F_RF 0x2 |
| /* Unknown Sequence Number */ |
| #define MP_F_USN 0x01 |
| /* Reason code Present */ |
| #define MP_F_RCODE 0x02 |
| |
| static void mesh_queue_preq(struct mesh_path *, u8); |
| |
| static inline u32 u32_field_get(u8 *preq_elem, int offset, bool ae) |
| { |
| if (ae) |
| offset += 6; |
| return get_unaligned_le32(preq_elem + offset); |
| } |
| |
| static inline u32 u16_field_get(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) (x + 3) |
| #define PREP_IE_ORIG_SN(x) u32_field_get(x, 9, 0); |
| #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) (AE_F_SET(x) ? x + 27 : x + 21) |
| #define PREP_IE_TARGET_SN(x) u32_field_get(x, 27, AE_F_SET(x)); |
| |
| #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) ((long) (y) - (long) (x) < 0) |
| #define SN_LT(x, y) ((long) (x) - (long) (y) < 0) |
| |
| #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) |
| |
| 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, |
| u8 *orig_addr, __le32 orig_sn, u8 target_flags, u8 *target, |
| __le32 target_sn, const u8 *da, u8 hop_count, u8 ttl, |
| __le32 lifetime, __le32 metric, __le32 preq_id, |
| struct ieee80211_sub_if_data *sdata) |
| { |
| struct ieee80211_local *local = sdata->local; |
| struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400); |
| struct ieee80211_mgmt *mgmt; |
| u8 *pos; |
| int ie_len; |
| |
| if (!skb) |
| return -1; |
| skb_reserve(skb, local->hw.extra_tx_headroom); |
| /* 25 is the size of the common mgmt part (24) plus the size of the |
| * common action part (1) |
| */ |
| mgmt = (struct ieee80211_mgmt *) |
| skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action)); |
| memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action)); |
| 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 = MESH_PATH_SEL_CATEGORY; |
| mgmt->u.action.u.mesh_action.action_code = MESH_PATH_SEL_ACTION; |
| |
| switch (action) { |
| case MPATH_PREQ: |
| mhwmp_dbg("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("sending PREP to %pM\n", target); |
| ie_len = 31; |
| pos = skb_put(skb, 2 + ie_len); |
| *pos++ = WLAN_EID_PREP; |
| break; |
| case MPATH_RANN: |
| mhwmp_dbg("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; |
| break; |
| } |
| *pos++ = ie_len; |
| *pos++ = flags; |
| *pos++ = hop_count; |
| *pos++ = ttl; |
| if (action == MPATH_PREQ) { |
| memcpy(pos, &preq_id, 4); |
| pos += 4; |
| } |
| memcpy(pos, orig_addr, ETH_ALEN); |
| pos += ETH_ALEN; |
| memcpy(pos, &orig_sn, 4); |
| pos += 4; |
| if (action != MPATH_RANN) { |
| memcpy(pos, &lifetime, 4); |
| pos += 4; |
| } |
| memcpy(pos, &metric, 4); |
| pos += 4; |
| if (action == MPATH_PREQ) { |
| /* destination count */ |
| *pos++ = 1; |
| *pos++ = target_flags; |
| } |
| if (action != MPATH_RANN) { |
| memcpy(pos, target, ETH_ALEN); |
| pos += ETH_ALEN; |
| memcpy(pos, &target_sn, 4); |
| } |
| |
| ieee80211_tx_skb(sdata, skb); |
| return 0; |
| } |
| |
| /** |
| * mesh_send_path error - Sends a PERR mesh management frame |
| * |
| * @target: broken destination |
| * @target_sn: SN of the broken destination |
| * @target_rcode: reason code for this PERR |
| * @ra: node this frame is addressed to |
| */ |
| int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn, |
| __le16 target_rcode, const u8 *ra, |
| struct ieee80211_sub_if_data *sdata) |
| { |
| struct ieee80211_local *local = sdata->local; |
| struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400); |
| struct ieee80211_mgmt *mgmt; |
| u8 *pos; |
| int ie_len; |
| |
| if (!skb) |
| return -1; |
| skb_reserve(skb, local->hw.extra_tx_headroom); |
| /* 25 is the size of the common mgmt part (24) plus the size of the |
| * common action part (1) |
| */ |
| mgmt = (struct ieee80211_mgmt *) |
| skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action)); |
| memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action)); |
| 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 is left zeroed, wildcard value */ |
| mgmt->u.action.category = MESH_PATH_SEL_CATEGORY; |
| mgmt->u.action.u.mesh_action.action_code = MESH_PATH_SEL_ACTION; |
| ie_len = 15; |
| pos = skb_put(skb, 2 + ie_len); |
| *pos++ = WLAN_EID_PERR; |
| *pos++ = ie_len; |
| /* ttl */ |
| *pos++ = MESH_TTL; |
| /* number of destinations */ |
| *pos++ = 1; |
| /* |
| * flags bit, bit 1 is unset if we know the sequence number and |
| * bit 2 is set if we have a reason code |
| */ |
| *pos = 0; |
| if (!target_sn) |
| *pos |= MP_F_USN; |
| if (target_rcode) |
| *pos |= MP_F_RCODE; |
| pos++; |
| memcpy(pos, target, ETH_ALEN); |
| pos += ETH_ALEN; |
| memcpy(pos, &target_sn, 4); |
| pos += 4; |
| memcpy(pos, &target_rcode, 2); |
| |
| ieee80211_tx_skb(sdata, skb); |
| return 0; |
| } |
| |
| void ieee80211s_update_metric(struct ieee80211_local *local, |
| struct sta_info *stainfo, struct sk_buff *skb) |
| { |
| struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb); |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| int failed; |
| |
| if (!ieee80211_is_data(hdr->frame_control)) |
| return; |
| |
| failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK); |
| |
| /* moving average, scaled to 100 */ |
| stainfo->fail_avg = ((80 * stainfo->fail_avg + 5) / 100 + 20 * failed); |
| if (stainfo->fail_avg > 95) |
| mesh_plink_broken(stainfo); |
| } |
| |
| static u32 airtime_link_metric_get(struct ieee80211_local *local, |
| struct sta_info *sta) |
| { |
| struct ieee80211_supported_band *sband; |
| /* 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; |
| |
| sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; |
| |
| if (sta->fail_avg >= 100) |
| return MAX_METRIC; |
| |
| if (sta->last_tx_rate.flags & IEEE80211_TX_RC_MCS) |
| return MAX_METRIC; |
| |
| err = (sta->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. |
| */ |
| rate = sband->bitrates[sta->last_tx_rate.idx].bitrate; |
| tx_time = (device_constant + 10 * test_frame_len / rate); |
| estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); |
| result = (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) |
| * |
| * 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 destination in |
| * the Path Request. The draft refers to that MP as the |
| * destination address, even though usually it is the origin of |
| * the PREP frame. 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_ORIG_ADDR(hwmp_ie); |
| orig_sn = PREP_IE_ORIG_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 (memcmp(orig_addr, sdata->vif.addr, ETH_ALEN) == 0) { |
| /* 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 && |
| action == MPATH_PREQ && |
| 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 (memcmp(orig_addr, ta, ETH_ALEN) == 0) |
| 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->flags &= ~MESH_PATH_SN_VALID; |
| 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; |
| } |
| |
| static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata, |
| struct ieee80211_mgmt *mgmt, |
| u8 *preq_elem, u32 metric) |
| { |
| struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| struct mesh_path *mpath; |
| u8 *target_addr, *orig_addr; |
| u8 target_flags, ttl; |
| u32 orig_sn, target_sn, lifetime; |
| bool reply = false; |
| bool forward = true; |
| |
| /* 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); |
| |
| mhwmp_dbg("received PREQ from %pM\n", orig_addr); |
| |
| if (memcmp(target_addr, sdata->vif.addr, ETH_ALEN) == 0) { |
| mhwmp_dbg("PREQ is for us\n"); |
| forward = false; |
| reply = true; |
| metric = 0; |
| if (time_after(jiffies, ifmsh->last_sn_update + |
| net_traversal_jiffies(sdata)) || |
| time_before(jiffies, ifmsh->last_sn_update)) { |
| target_sn = ++ifmsh->sn; |
| ifmsh->last_sn_update = jiffies; |
| } |
| } else { |
| rcu_read_lock(); |
| mpath = mesh_path_lookup(target_addr, sdata); |
| 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 & MP_F_DO)) && |
| (mpath->flags & MESH_PATH_ACTIVE)) { |
| reply = true; |
| metric = mpath->metric; |
| target_sn = mpath->sn; |
| if (target_flags & MP_F_RF) |
| target_flags |= MP_F_DO; |
| else |
| forward = false; |
| } |
| } |
| rcu_read_unlock(); |
| } |
| |
| if (reply) { |
| lifetime = PREQ_IE_LIFETIME(preq_elem); |
| ttl = ifmsh->mshcfg.dot11MeshTTL; |
| if (ttl != 0) { |
| mhwmp_dbg("replying to the PREQ\n"); |
| mesh_path_sel_frame_tx(MPATH_PREP, 0, target_addr, |
| cpu_to_le32(target_sn), 0, orig_addr, |
| cpu_to_le32(orig_sn), mgmt->sa, 0, ttl, |
| cpu_to_le32(lifetime), cpu_to_le32(metric), |
| 0, sdata); |
| } else |
| ifmsh->mshstats.dropped_frames_ttl++; |
| } |
| |
| if (forward) { |
| u32 preq_id; |
| u8 hopcount, flags; |
| |
| ttl = PREQ_IE_TTL(preq_elem); |
| lifetime = PREQ_IE_LIFETIME(preq_elem); |
| if (ttl <= 1) { |
| ifmsh->mshstats.dropped_frames_ttl++; |
| return; |
| } |
| mhwmp_dbg("forwarding the PREQ from %pM\n", orig_addr); |
| --ttl; |
| flags = PREQ_IE_FLAGS(preq_elem); |
| preq_id = PREQ_IE_PREQ_ID(preq_elem); |
| hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; |
| mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, |
| cpu_to_le32(orig_sn), target_flags, target_addr, |
| cpu_to_le32(target_sn), broadcast_addr, |
| hopcount, ttl, cpu_to_le32(lifetime), |
| cpu_to_le32(metric), cpu_to_le32(preq_id), |
| sdata); |
| ifmsh->mshstats.fwded_mcast++; |
| ifmsh->mshstats.fwded_frames++; |
| } |
| } |
| |
| |
| static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata, |
| struct ieee80211_mgmt *mgmt, |
| u8 *prep_elem, u32 metric) |
| { |
| struct mesh_path *mpath; |
| u8 *target_addr, *orig_addr; |
| u8 ttl, hopcount, flags; |
| u8 next_hop[ETH_ALEN]; |
| u32 target_sn, orig_sn, lifetime; |
| |
| mhwmp_dbg("received PREP from %pM\n", PREP_IE_ORIG_ADDR(prep_elem)); |
| |
| /* Note that we divert from the draft nomenclature and denominate |
| * destination to what the draft refers to as origininator. So in this |
| * function destnation refers to the final destination of the PREP, |
| * which corresponds with the originator of the PREQ which this PREP |
| * replies |
| */ |
| target_addr = PREP_IE_TARGET_ADDR(prep_elem); |
| if (memcmp(target_addr, sdata->vif.addr, ETH_ALEN) == 0) |
| /* destination, no forwarding required */ |
| 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(target_addr, sdata); |
| 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, mpath->next_hop->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; |
| orig_addr = PREP_IE_ORIG_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, |
| cpu_to_le32(orig_sn), 0, target_addr, |
| cpu_to_le32(target_sn), mpath->next_hop->sta.addr, hopcount, |
| ttl, cpu_to_le32(lifetime), cpu_to_le32(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++; |
| return; |
| } |
| |
| 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; |
| u8 target_flags; |
| 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_flags = PERR_IE_TARGET_FLAGS(perr_elem); |
| 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, mpath->next_hop->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(); |
| } |
| |
| static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata, |
| struct ieee80211_mgmt *mgmt, |
| struct ieee80211_rann_ie *rann) |
| { |
| struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| struct mesh_path *mpath; |
| u8 *ta; |
| u8 ttl, flags, hopcount; |
| u8 *orig_addr; |
| u32 orig_sn, metric; |
| |
| ta = mgmt->sa; |
| ttl = rann->rann_ttl; |
| if (ttl <= 1) { |
| ifmsh->mshstats.dropped_frames_ttl++; |
| return; |
| } |
| ttl--; |
| flags = rann->rann_flags; |
| orig_addr = rann->rann_addr; |
| orig_sn = rann->rann_seq; |
| hopcount = rann->rann_hopcount; |
| hopcount++; |
| metric = rann->rann_metric; |
| mhwmp_dbg("received RANN from %pM\n", orig_addr); |
| |
| rcu_read_lock(); |
| mpath = mesh_path_lookup(orig_addr, sdata); |
| if (!mpath) { |
| mesh_path_add(orig_addr, sdata); |
| mpath = mesh_path_lookup(orig_addr, sdata); |
| if (!mpath) { |
| rcu_read_unlock(); |
| sdata->u.mesh.mshstats.dropped_frames_no_route++; |
| return; |
| } |
| mesh_queue_preq(mpath, |
| PREQ_Q_F_START | PREQ_Q_F_REFRESH); |
| } |
| if (mpath->sn < orig_sn) { |
| mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr, |
| cpu_to_le32(orig_sn), |
| 0, NULL, 0, broadcast_addr, |
| hopcount, ttl, 0, |
| cpu_to_le32(metric + mpath->metric), |
| 0, sdata); |
| mpath->sn = orig_sn; |
| } |
| 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 last_hop_metric; |
| |
| /* need action_code */ |
| if (len < IEEE80211_MIN_ACTION_SIZE + 1) |
| return; |
| |
| baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; |
| ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, |
| len - baselen, &elems); |
| |
| if (elems.preq) { |
| if (elems.preq_len != 37) |
| /* Right now we support just 1 destination and no AE */ |
| return; |
| last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.preq, |
| MPATH_PREQ); |
| if (last_hop_metric) |
| hwmp_preq_frame_process(sdata, mgmt, elems.preq, |
| last_hop_metric); |
| } |
| if (elems.prep) { |
| if (elems.prep_len != 31) |
| /* Right now we support no AE */ |
| return; |
| last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.prep, |
| MPATH_PREP); |
| if (last_hop_metric) |
| hwmp_prep_frame_process(sdata, mgmt, elems.prep, |
| last_hop_metric); |
| } |
| if (elems.perr) { |
| if (elems.perr_len != 15) |
| /* Right now we support only one destination per PERR */ |
| return; |
| hwmp_perr_frame_process(sdata, mgmt, elems.perr); |
| } |
| if (elems.rann) |
| hwmp_rann_frame_process(sdata, mgmt, elems.rann); |
| } |
| |
| /** |
| * 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("could not allocate PREQ node\n"); |
| return; |
| } |
| |
| spin_lock(&ifmsh->mesh_preq_queue_lock); |
| if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) { |
| spin_unlock(&ifmsh->mesh_preq_queue_lock); |
| kfree(preq_node); |
| if (printk_ratelimit()) |
| mhwmp_dbg("PREQ node queue full\n"); |
| return; |
| } |
| |
| memcpy(preq_node->dst, mpath->dst, ETH_ALEN); |
| preq_node->flags = flags; |
| |
| list_add_tail(&preq_node->list, &ifmsh->preq_queue.list); |
| ++ifmsh->preq_queue_len; |
| spin_unlock(&ifmsh->mesh_preq_queue_lock); |
| |
| if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata))) |
| ieee80211_queue_work(&sdata->local->hw, &ifmsh->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, &ifmsh->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; |
| 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(preq_node->dst, sdata); |
| if (!mpath) |
| goto enddiscovery; |
| |
| spin_lock_bh(&mpath->state_lock); |
| 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.dot11MeshTTL; |
| 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 = MP_F_DO; |
| else |
| target_flags = MP_F_RF; |
| |
| spin_unlock_bh(&mpath->state_lock); |
| mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, |
| cpu_to_le32(ifmsh->sn), target_flags, mpath->dst, |
| cpu_to_le32(mpath->sn), broadcast_addr, 0, |
| ttl, cpu_to_le32(lifetime), 0, |
| cpu_to_le32(ifmsh->preq_id++), sdata); |
| mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); |
| |
| enddiscovery: |
| rcu_read_unlock(); |
| kfree(preq_node); |
| } |
| |
| /** |
| * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame |
| * |
| * @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. If no next hop is |
| * found, the function will start a path discovery and queue the frame so it is |
| * sent when the path is resolved. This means the caller must not free the skb |
| * in this case. |
| */ |
| int mesh_nexthop_lookup(struct sk_buff *skb, |
| struct ieee80211_sub_if_data *sdata) |
| { |
| struct sk_buff *skb_to_free = NULL; |
| struct mesh_path *mpath; |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| u8 *target_addr = hdr->addr3; |
| int err = 0; |
| |
| rcu_read_lock(); |
| mpath = mesh_path_lookup(target_addr, sdata); |
| |
| if (!mpath) { |
| mesh_path_add(target_addr, sdata); |
| mpath = mesh_path_lookup(target_addr, sdata); |
| if (!mpath) { |
| sdata->u.mesh.mshstats.dropped_frames_no_route++; |
| err = -ENOSPC; |
| goto endlookup; |
| } |
| } |
| |
| if (mpath->flags & MESH_PATH_ACTIVE) { |
| if (time_after(jiffies, |
| mpath->exp_time + |
| msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) && |
| !memcmp(sdata->vif.addr, hdr->addr4, ETH_ALEN) && |
| !(mpath->flags & MESH_PATH_RESOLVING) && |
| !(mpath->flags & MESH_PATH_FIXED)) { |
| mesh_queue_preq(mpath, |
| PREQ_Q_F_START | PREQ_Q_F_REFRESH); |
| } |
| memcpy(hdr->addr1, mpath->next_hop->sta.addr, ETH_ALEN); |
| } else { |
| struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
| if (!(mpath->flags & MESH_PATH_RESOLVING)) { |
| /* Start discovery only if it is not running yet */ |
| 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->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; |
| skb_queue_tail(&mpath->frame_queue, skb); |
| if (skb_to_free) |
| mesh_path_discard_frame(skb_to_free, sdata); |
| err = -ENOENT; |
| } |
| |
| endlookup: |
| rcu_read_unlock(); |
| return err; |
| } |
| |
| void mesh_path_timer(unsigned long data) |
| { |
| struct ieee80211_sub_if_data *sdata; |
| struct mesh_path *mpath; |
| |
| rcu_read_lock(); |
| mpath = (struct mesh_path *) data; |
| mpath = rcu_dereference(mpath); |
| if (!mpath) |
| goto endmpathtimer; |
| sdata = mpath->sdata; |
| |
| if (sdata->local->quiescing) { |
| rcu_read_unlock(); |
| 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); |
| else if (mpath->discovery_retries < max_preq_retries(sdata)) { |
| ++mpath->discovery_retries; |
| mpath->discovery_timeout *= 2; |
| mesh_queue_preq(mpath, 0); |
| } else { |
| mpath->flags = 0; |
| mpath->exp_time = jiffies; |
| mesh_path_flush_pending(mpath); |
| } |
| |
| spin_unlock_bh(&mpath->state_lock); |
| endmpathtimer: |
| rcu_read_unlock(); |
| } |
| |
| void |
| mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata) |
| { |
| struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| |
| mesh_path_sel_frame_tx(MPATH_RANN, 0, sdata->vif.addr, |
| cpu_to_le32(++ifmsh->sn), |
| 0, NULL, 0, broadcast_addr, |
| 0, MESH_TTL, 0, 0, 0, sdata); |
| } |