--- /dev/null
+/*
+ * Copyright (c) 2008 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"
+
+#define IEEE80211_FC(type, stype) cpu_to_le16(type | stype)
+
+#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
+
+/* 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) le32_to_cpu(*((u32 *) (x + 3)))
+#define PREQ_IE_ORIG_ADDR(x) (x + 7)
+#define PREQ_IE_ORIG_DSN(x) le32_to_cpu(*((u32 *) (x + 13)))
+#define PREQ_IE_LIFETIME(x) le32_to_cpu(*((u32 *) \
+ (AE_F_SET(x) ? x + 23 : x + 17)))
+#define PREQ_IE_METRIC(x) le32_to_cpu(*((u32 *) \
+ (AE_F_SET(x) ? x + 27 : x + 21)))
+#define PREQ_IE_DST_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26))
+#define PREQ_IE_DST_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27)
+#define PREQ_IE_DST_DSN(x) le32_to_cpu(*((u32 *) \
+ (AE_F_SET(x) ? x + 39 : x + 33)))
+
+
+#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_DSN(x) le32_to_cpu(*((u32 *) (x + 9)))
+#define PREP_IE_LIFETIME(x) le32_to_cpu(*((u32 *) \
+ (AE_F_SET(x) ? x + 19 : x + 13)))
+#define PREP_IE_METRIC(x) le32_to_cpu(*((u32 *) \
+ (AE_F_SET(x) ? x + 23 : x + 17)))
+#define PREP_IE_DST_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21)
+#define PREP_IE_DST_DSN(x) le32_to_cpu(*((u32 *) \
+ (AE_F_SET(x) ? x + 33 : x + 27)))
+
+#define PERR_IE_DST_ADDR(x) (x + 2)
+#define PERR_IE_DST_DSN(x) le32_to_cpu(*((u32 *) (x + 8)))
+
+#define TU_TO_EXP_TIME(x) (jiffies + msecs_to_jiffies(x * 1024 / 1000))
+#define MSEC_TO_TU(x) (x*1000/1024)
+#define DSN_GT(x, y) ((long) (y) - (long) (x) < 0)
+#define DSN_LT(x, y) ((long) (x) - (long) (y) < 0)
+
+#define net_traversal_jiffies(s) \
+ msecs_to_jiffies(s->u.sta.mshcfg.dot11MeshHWMPnetDiameterTraversalTime)
+#define default_lifetime(s) \
+ MSEC_TO_TU(s->u.sta.mshcfg.dot11MeshHWMPactivePathTimeout)
+#define min_preq_int_jiff(s) \
+ (msecs_to_jiffies(s->u.sta.mshcfg.dot11MeshHWMPpreqMinInterval))
+#define max_preq_retries(s) (s->u.sta.mshcfg.dot11MeshHWMPmaxPREQretries)
+#define disc_timeout_jiff(s) \
+ msecs_to_jiffies(sdata->u.sta.mshcfg.min_discovery_timeout)
+
+enum mpath_frame_type {
+ MPATH_PREQ = 0,
+ MPATH_PREP,
+ MPATH_PERR
+};
+
+static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
+ u8 *orig_addr, __le32 orig_dsn, u8 dst_flags, u8 *dst,
+ __le32 dst_dsn, u8 *da, u8 hop_count, u8 ttl, __le32 lifetime,
+ __le32 metric, __le32 preq_id, struct net_device *dev)
+{
+ struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+ 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 = IEEE80211_FC(IEEE80211_FTYPE_MGMT,
+ IEEE80211_STYPE_ACTION);
+
+ memcpy(mgmt->da, da, ETH_ALEN);
+ memcpy(mgmt->sa, dev->dev_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 = action;
+
+ switch (action) {
+ case MPATH_PREQ:
+ ie_len = 37;
+ pos = skb_put(skb, 2 + ie_len);
+ *pos++ = WLAN_EID_PREQ;
+ break;
+ case MPATH_PREP:
+ ie_len = 31;
+ pos = skb_put(skb, 2 + ie_len);
+ *pos++ = WLAN_EID_PREP;
+ break;
+ default:
+ kfree(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_dsn, 4);
+ pos += 4;
+ memcpy(pos, &lifetime, 4);
+ pos += 4;
+ memcpy(pos, &metric, 4);
+ pos += 4;
+ if (action == MPATH_PREQ) {
+ /* destination count */
+ *pos++ = 1;
+ *pos++ = dst_flags;
+ }
+ memcpy(pos, dst, ETH_ALEN);
+ pos += ETH_ALEN;
+ memcpy(pos, &dst_dsn, 4);
+
+ ieee80211_sta_tx(dev, skb, 0);
+ return 0;
+}
+
+/**
+ * mesh_send_path error - Sends a PERR mesh management frame
+ *
+ * @dst: broken destination
+ * @dst_dsn: dsn of the broken destination
+ * @ra: node this frame is addressed to
+ */
+int mesh_path_error_tx(u8 *dst, __le32 dst_dsn, u8 *ra,
+ struct net_device *dev)
+{
+ struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+ 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 = IEEE80211_FC(IEEE80211_FTYPE_MGMT,
+ IEEE80211_STYPE_ACTION);
+
+ memcpy(mgmt->da, ra, ETH_ALEN);
+ memcpy(mgmt->sa, dev->dev_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 = MPATH_PERR;
+ ie_len = 12;
+ pos = skb_put(skb, 2 + ie_len);
+ *pos++ = WLAN_EID_PERR;
+ *pos++ = ie_len;
+ /* mode flags, reserved */
+ *pos++ = 0;
+ /* number of destinations */
+ *pos++ = 1;
+ memcpy(pos, dst, ETH_ALEN);
+ pos += ETH_ALEN;
+ memcpy(pos, &dst_dsn, 4);
+
+ ieee80211_sta_tx(dev, skb, 0);
+ return 0;
+}
+
+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;
+ 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->txrate_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
+ *
+ * @dev: local mesh interface
+ * @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 fram.
+ *
+ * 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 net_device *dev,
+ struct ieee80211_mgmt *mgmt,
+ u8 *hwmp_ie)
+{
+ struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+ struct mesh_path *mpath;
+ struct sta_info *sta;
+ bool fresh_info;
+ u8 *orig_addr, *ta;
+ u32 orig_dsn, orig_metric;
+ unsigned long orig_lifetime, exp_time;
+ u32 last_hop_metric, new_metric;
+ bool process = true;
+ u8 action = mgmt->u.action.u.mesh_action.action_code;
+
+ rcu_read_lock();
+ sta = sta_info_get(local, mgmt->sa);
+ if (!sta)
+ 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_dsn = PREQ_IE_ORIG_DSN(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_dsn = PREP_IE_ORIG_DSN(hwmp_ie);
+ orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
+ orig_metric = PREP_IE_METRIC(hwmp_ie);
+ break;
+ default:
+ sta_info_put(sta);
+ 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, dev->dev_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, dev);
+ 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_DSN_VALID)) {
+ if (DSN_GT(mpath->dsn, orig_dsn) ||
+ (mpath->dsn == orig_dsn &&
+ action == MPATH_PREQ &&
+ new_metric > mpath->metric)) {
+ process = false;
+ fresh_info = false;
+ }
+ }
+ } else {
+ mesh_path_add(orig_addr, dev);
+ mpath = mesh_path_lookup(orig_addr, dev);
+ if (!mpath) {
+ rcu_read_unlock();
+ sta_info_put(sta);
+ return 0;
+ }
+ spin_lock_bh(&mpath->state_lock);
+ }
+
+ if (fresh_info) {
+ mesh_path_assign_nexthop(mpath, sta);
+ mpath->flags |= MESH_PATH_DSN_VALID;
+ mpath->metric = new_metric;
+ mpath->dsn = orig_dsn;
+ 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, dev);
+ 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, dev);
+ mpath = mesh_path_lookup(ta, dev);
+ if (!mpath) {
+ rcu_read_unlock();
+ sta_info_put(sta);
+ return 0;
+ }
+ spin_lock_bh(&mpath->state_lock);
+ }
+
+ if (fresh_info) {
+ mesh_path_assign_nexthop(mpath, sta);
+ mpath->flags &= ~MESH_PATH_DSN_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);
+ }
+
+ sta_info_put(sta);
+ rcu_read_unlock();
+
+ return process ? new_metric : 0;
+}
+
+static void hwmp_preq_frame_process(struct net_device *dev,
+ struct ieee80211_mgmt *mgmt,
+ u8 *preq_elem, u32 metric) {
+ struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+ struct ieee80211_if_sta *ifsta = &sdata->u.sta;
+ struct mesh_path *mpath;
+ u8 *dst_addr, *orig_addr;
+ u8 dst_flags, ttl;
+ u32 orig_dsn, dst_dsn, lifetime;
+ bool reply = false;
+ bool forward = true;
+
+ /* Update destination DSN, if present */
+ dst_addr = PREQ_IE_DST_ADDR(preq_elem);
+ orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
+ dst_dsn = PREQ_IE_DST_DSN(preq_elem);
+ orig_dsn = PREQ_IE_ORIG_DSN(preq_elem);
+ dst_flags = PREQ_IE_DST_F(preq_elem);
+
+ if (memcmp(dst_addr, dev->dev_addr, ETH_ALEN) == 0) {
+ forward = false;
+ reply = true;
+ metric = 0;
+ if (time_after(jiffies, ifsta->last_dsn_update +
+ net_traversal_jiffies(sdata)) ||
+ time_before(jiffies, ifsta->last_dsn_update)) {
+ dst_dsn = ++ifsta->dsn;
+ ifsta->last_dsn_update = jiffies;
+ }
+ } else {
+ rcu_read_lock();
+ mpath = mesh_path_lookup(dst_addr, dev);
+ if (mpath) {
+ if ((!(mpath->flags & MESH_PATH_DSN_VALID)) ||
+ DSN_LT(mpath->dsn, dst_dsn)) {
+ mpath->dsn = dst_dsn;
+ mpath->flags &= MESH_PATH_DSN_VALID;
+ } else if ((!(dst_flags & MP_F_DO)) &&
+ (mpath->flags & MESH_PATH_ACTIVE)) {
+ reply = true;
+ metric = mpath->metric;
+ dst_dsn = mpath->dsn;
+ if (dst_flags & MP_F_RF)
+ dst_flags |= MP_F_DO;
+ else
+ forward = false;
+ }
+ }
+ rcu_read_unlock();
+ }
+
+ if (reply) {
+ lifetime = PREQ_IE_LIFETIME(preq_elem);
+ ttl = ifsta->mshcfg.dot11MeshTTL;
+ if (ttl != 0)
+ mesh_path_sel_frame_tx(MPATH_PREP, 0, dst_addr,
+ __cpu_to_le32(dst_dsn), 0, orig_addr,
+ __cpu_to_le32(orig_dsn), mgmt->sa, 0, ttl,
+ __cpu_to_le32(lifetime), __cpu_to_le32(metric),
+ 0, dev);
+ else
+ ifsta->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) {
+ ifsta->mshstats.dropped_frames_ttl++;
+ return;
+ }
+ --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_dsn), dst_flags, dst_addr,
+ __cpu_to_le32(dst_dsn), dev->broadcast,
+ hopcount, ttl, __cpu_to_le32(lifetime),
+ __cpu_to_le32(metric), __cpu_to_le32(preq_id),
+ dev);
+ ifsta->mshstats.fwded_frames++;
+ }
+}
+
+
+static void hwmp_prep_frame_process(struct net_device *dev,
+ struct ieee80211_mgmt *mgmt,
+ u8 *prep_elem, u32 metric)
+{
+ struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+ struct mesh_path *mpath;
+ u8 *dst_addr, *orig_addr;
+ u8 ttl, hopcount, flags;
+ u8 next_hop[ETH_ALEN];
+ u32 dst_dsn, orig_dsn, lifetime;
+
+ /* 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
+ */
+ dst_addr = PREP_IE_DST_ADDR(prep_elem);
+ if (memcmp(dst_addr, dev->dev_addr, ETH_ALEN) == 0)
+ /* destination, no forwarding required */
+ return;
+
+ ttl = PREP_IE_TTL(prep_elem);
+ if (ttl <= 1) {
+ sdata->u.sta.mshstats.dropped_frames_ttl++;
+ return;
+ }
+
+ rcu_read_lock();
+ mpath = mesh_path_lookup(dst_addr, dev);
+ 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->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);
+ dst_dsn = PREP_IE_DST_DSN(prep_elem);
+ orig_dsn = PREP_IE_ORIG_DSN(prep_elem);
+
+ mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr,
+ __cpu_to_le32(orig_dsn), 0, dst_addr,
+ __cpu_to_le32(dst_dsn), mpath->next_hop->addr, hopcount, ttl,
+ __cpu_to_le32(lifetime), __cpu_to_le32(metric),
+ 0, dev);
+ rcu_read_unlock();
+ sdata->u.sta.mshstats.fwded_frames++;
+ return;
+
+fail:
+ rcu_read_unlock();
+ sdata->u.sta.mshstats.dropped_frames_no_route++;
+ return;
+}
+
+static void hwmp_perr_frame_process(struct net_device *dev,
+ struct ieee80211_mgmt *mgmt, u8 *perr_elem)
+{
+ struct mesh_path *mpath;
+ u8 *ta, *dst_addr;
+ u32 dst_dsn;
+
+ ta = mgmt->sa;
+ dst_addr = PERR_IE_DST_ADDR(perr_elem);
+ dst_dsn = PERR_IE_DST_DSN(perr_elem);
+ rcu_read_lock();
+ mpath = mesh_path_lookup(dst_addr, dev);
+ if (mpath) {
+ spin_lock_bh(&mpath->state_lock);
+ if (mpath->flags & MESH_PATH_ACTIVE &&
+ memcmp(ta, mpath->next_hop->addr, ETH_ALEN) == 0 &&
+ (!(mpath->flags & MESH_PATH_DSN_VALID) ||
+ DSN_GT(dst_dsn, mpath->dsn))) {
+ mpath->flags &= ~MESH_PATH_ACTIVE;
+ mpath->dsn = dst_dsn;
+ spin_unlock_bh(&mpath->state_lock);
+ mesh_path_error_tx(dst_addr, dst_dsn, dev->broadcast,
+ dev);
+ } else
+ spin_unlock_bh(&mpath->state_lock);
+ }
+ rcu_read_unlock();
+}
+
+
+
+void mesh_rx_path_sel_frame(struct net_device *dev,
+ struct ieee80211_mgmt *mgmt,
+ size_t len)
+{
+ struct ieee802_11_elems elems;
+ size_t baselen;
+ u32 last_hop_metric;
+
+ 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);
+
+ switch (mgmt->u.action.u.mesh_action.action_code) {
+ case MPATH_PREQ:
+ if (!elems.preq || elems.preq_len != 37)
+ /* Right now we support just 1 destination and no AE */
+ return;
+ last_hop_metric = hwmp_route_info_get(dev, mgmt, elems.preq);
+ if (!last_hop_metric)
+ return;
+ hwmp_preq_frame_process(dev, mgmt, elems.preq, last_hop_metric);
+ break;
+ case MPATH_PREP:
+ if (!elems.prep || elems.prep_len != 31)
+ /* Right now we support no AE */
+ return;
+ last_hop_metric = hwmp_route_info_get(dev, mgmt, elems.prep);
+ if (!last_hop_metric)
+ return;
+ hwmp_prep_frame_process(dev, mgmt, elems.prep, last_hop_metric);
+ break;
+ case MPATH_PERR:
+ if (!elems.perr || elems.perr_len != 12)
+ /* Right now we support only one destination per PERR */
+ return;
+ hwmp_perr_frame_process(dev, mgmt, elems.perr);
+ default:
+ return;
+ }
+
+}
+
+/**
+ * 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 =
+ IEEE80211_DEV_TO_SUB_IF(mpath->dev);
+ struct ieee80211_if_sta *ifsta = &sdata->u.sta;
+ struct mesh_preq_queue *preq_node;
+
+ preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_KERNEL);
+ if (!preq_node) {
+ printk(KERN_DEBUG "Mesh HWMP: could not allocate PREQ node\n");
+ return;
+ }
+
+ spin_lock(&ifsta->mesh_preq_queue_lock);
+ if (ifsta->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
+ spin_unlock(&ifsta->mesh_preq_queue_lock);
+ kfree(preq_node);
+ if (printk_ratelimit())
+ printk(KERN_DEBUG "Mesh HWMP: PREQ node queue full\n");
+ return;
+ }
+
+ memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
+ preq_node->flags = flags;
+
+ list_add_tail(&preq_node->list, &ifsta->preq_queue.list);
+ ++ifsta->preq_queue_len;
+ spin_unlock(&ifsta->mesh_preq_queue_lock);
+
+ if (time_after(jiffies, ifsta->last_preq + min_preq_int_jiff(sdata)))
+ queue_work(sdata->local->hw.workqueue, &ifsta->work);
+
+ else if (time_before(jiffies, ifsta->last_preq)) {
+ /* avoid long wait if did not send preqs for a long time
+ * and jiffies wrapped around
+ */
+ ifsta->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
+ queue_work(sdata->local->hw.workqueue, &ifsta->work);
+ } else
+ mod_timer(&ifsta->mesh_path_timer, ifsta->last_preq +
+ min_preq_int_jiff(sdata));
+}
+
+/**
+ * mesh_path_start_discovery - launch a path discovery from the PREQ queue
+ *
+ * @dev: local mesh interface
+ */
+void mesh_path_start_discovery(struct net_device *dev)
+{
+ struct ieee80211_sub_if_data *sdata =
+ IEEE80211_DEV_TO_SUB_IF(dev);
+ struct ieee80211_if_sta *ifsta = &sdata->u.sta;
+ struct mesh_preq_queue *preq_node;
+ struct mesh_path *mpath;
+ u8 ttl, dst_flags;
+ u32 lifetime;
+
+ spin_lock(&ifsta->mesh_preq_queue_lock);
+ if (!ifsta->preq_queue_len ||
+ time_before(jiffies, ifsta->last_preq +
+ min_preq_int_jiff(sdata))) {
+ spin_unlock(&ifsta->mesh_preq_queue_lock);
+ return;
+ }
+
+ preq_node = list_first_entry(&ifsta->preq_queue.list,
+ struct mesh_preq_queue, list);
+ list_del(&preq_node->list);
+ --ifsta->preq_queue_len;
+ spin_unlock(&ifsta->mesh_preq_queue_lock);
+
+ rcu_read_lock();
+ mpath = mesh_path_lookup(preq_node->dst, dev);
+ 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;
+ }
+
+ ifsta->last_preq = jiffies;
+
+ if (time_after(jiffies, ifsta->last_dsn_update +
+ net_traversal_jiffies(sdata)) ||
+ time_before(jiffies, ifsta->last_dsn_update)) {
+ ++ifsta->dsn;
+ sdata->u.sta.last_dsn_update = jiffies;
+ }
+ lifetime = default_lifetime(sdata);
+ ttl = sdata->u.sta.mshcfg.dot11MeshTTL;
+ if (ttl == 0) {
+ sdata->u.sta.mshstats.dropped_frames_ttl++;
+ spin_unlock_bh(&mpath->state_lock);
+ goto enddiscovery;
+ }
+
+ if (preq_node->flags & PREQ_Q_F_REFRESH)
+ dst_flags = MP_F_DO;
+ else
+ dst_flags = MP_F_RF;
+
+ spin_unlock_bh(&mpath->state_lock);
+ mesh_path_sel_frame_tx(MPATH_PREQ, 0, dev->dev_addr,
+ __cpu_to_le32(ifsta->dsn), dst_flags, mpath->dst,
+ __cpu_to_le32(mpath->dsn), dev->broadcast, 0,
+ ttl, __cpu_to_le32(lifetime), 0,
+ __cpu_to_le32(ifsta->preq_id++), dev);
+ mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
+
+enddiscovery:
+ rcu_read_unlock();
+ kfree(preq_node);
+}
+
+/**
+ * ieee80211s_lookup_nexthop - put the appropriate next hop on a mesh frame
+ *
+ * @next_hop: output argument for next hop address
+ * @skb: frame to be sent
+ * @dev: network device 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(u8 *next_hop, struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+ struct sk_buff *skb_to_free = NULL;
+ struct mesh_path *mpath;
+ int err = 0;
+
+ rcu_read_lock();
+ mpath = mesh_path_lookup(skb->data, dev);
+
+ if (!mpath) {
+ mesh_path_add(skb->data, dev);
+ mpath = mesh_path_lookup(skb->data, dev);
+ if (!mpath) {
+ dev_kfree_skb(skb);
+ sdata->u.sta.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.sta.mshcfg.path_refresh_time))
+ && skb->pkt_type != PACKET_OTHERHOST
+ && !(mpath->flags & MESH_PATH_RESOLVING)
+ && !(mpath->flags & MESH_PATH_FIXED)) {
+ mesh_queue_preq(mpath,
+ PREQ_Q_F_START | PREQ_Q_F_REFRESH);
+ }
+ memcpy(next_hop, mpath->next_hop->addr,
+ ETH_ALEN);
+ } else {
+ 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 = mpath->frame_queue.next;
+ skb_unlink(skb_to_free, &mpath->frame_queue);
+ }
+
+ skb_queue_tail(&mpath->frame_queue, skb);
+ if (skb_to_free)
+ mesh_path_discard_frame(skb_to_free, dev);
+ 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;
+ bool delete = false;
+
+ rcu_read_lock();
+ mpath = (struct mesh_path *) data;
+ mpath = rcu_dereference(mpath);
+ if (!mpath)
+ goto endmpathtimer;
+ spin_lock_bh(&mpath->state_lock);
+ sdata = IEEE80211_DEV_TO_SUB_IF(mpath->dev);
+ if (mpath->flags & MESH_PATH_DELETE) {
+ mpath->flags = 0;
+ delete = true;
+ } else 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();
+ if (delete)
+ mesh_path_del(mpath->dst, mpath->dev);
+}
projects / linux-2.6 / commitdiff