Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2008 open80211s Ltd. |
| 3 | * Author: Luis Carlos Cobo <luisca@cozybit.com> |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License version 2 as |
| 7 | * published by the Free Software Foundation. |
| 8 | */ |
| 9 | |
Luis Carlos Cobo | a00de5d | 2008-02-29 17:07:54 -0800 | [diff] [blame^] | 10 | #include <asm/unaligned.h> |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 11 | #include "mesh.h" |
| 12 | |
| 13 | #define IEEE80211_FC(type, stype) cpu_to_le16(type | stype) |
| 14 | |
| 15 | #define TEST_FRAME_LEN 8192 |
| 16 | #define MAX_METRIC 0xffffffff |
| 17 | #define ARITH_SHIFT 8 |
| 18 | |
| 19 | /* Number of frames buffered per destination for unresolved destinations */ |
| 20 | #define MESH_FRAME_QUEUE_LEN 10 |
| 21 | #define MAX_PREQ_QUEUE_LEN 64 |
| 22 | |
| 23 | /* Destination only */ |
| 24 | #define MP_F_DO 0x1 |
| 25 | /* Reply and forward */ |
| 26 | #define MP_F_RF 0x2 |
| 27 | |
Luis Carlos Cobo | a00de5d | 2008-02-29 17:07:54 -0800 | [diff] [blame^] | 28 | static inline u32 u32_field_get(u8 *preq_elem, int offset, bool ae) |
| 29 | { |
| 30 | if (ae) |
| 31 | offset += 6; |
| 32 | return le32_to_cpu(get_unaligned((__le32 *) (preq_elem + offset))); |
| 33 | } |
| 34 | |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 35 | /* HWMP IE processing macros */ |
Luis Carlos Cobo | a00de5d | 2008-02-29 17:07:54 -0800 | [diff] [blame^] | 36 | #define AE_F (1<<6) |
| 37 | #define AE_F_SET(x) (*x & AE_F) |
| 38 | #define PREQ_IE_FLAGS(x) (*(x)) |
| 39 | #define PREQ_IE_HOPCOUNT(x) (*(x + 1)) |
| 40 | #define PREQ_IE_TTL(x) (*(x + 2)) |
| 41 | #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0) |
| 42 | #define PREQ_IE_ORIG_ADDR(x) (x + 7) |
| 43 | #define PREQ_IE_ORIG_DSN(x) u32_field_get(x, 13, 0); |
| 44 | #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x)); |
| 45 | #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x)); |
| 46 | #define PREQ_IE_DST_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26)) |
| 47 | #define PREQ_IE_DST_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27) |
| 48 | #define PREQ_IE_DST_DSN(x) u32_field_get(x, 33, AE_F_SET(x)); |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 49 | |
| 50 | |
Luis Carlos Cobo | a00de5d | 2008-02-29 17:07:54 -0800 | [diff] [blame^] | 51 | #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x) |
| 52 | #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x) |
| 53 | #define PREP_IE_TTL(x) PREQ_IE_TTL(x) |
| 54 | #define PREP_IE_ORIG_ADDR(x) (x + 3) |
| 55 | #define PREP_IE_ORIG_DSN(x) u32_field_get(x, 9, 0); |
| 56 | #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x)); |
| 57 | #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x)); |
| 58 | #define PREP_IE_DST_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21) |
| 59 | #define PREP_IE_DST_DSN(x) u32_field_get(x, 27, AE_F_SET(x)); |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 60 | |
Luis Carlos Cobo | a00de5d | 2008-02-29 17:07:54 -0800 | [diff] [blame^] | 61 | #define PERR_IE_DST_ADDR(x) (x + 2) |
| 62 | #define PERR_IE_DST_DSN(x) u32_field_get(x, 8, 0); |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 63 | |
| 64 | #define TU_TO_EXP_TIME(x) (jiffies + msecs_to_jiffies(x * 1024 / 1000)) |
| 65 | #define MSEC_TO_TU(x) (x*1000/1024) |
| 66 | #define DSN_GT(x, y) ((long) (y) - (long) (x) < 0) |
| 67 | #define DSN_LT(x, y) ((long) (x) - (long) (y) < 0) |
| 68 | |
| 69 | #define net_traversal_jiffies(s) \ |
| 70 | msecs_to_jiffies(s->u.sta.mshcfg.dot11MeshHWMPnetDiameterTraversalTime) |
| 71 | #define default_lifetime(s) \ |
| 72 | MSEC_TO_TU(s->u.sta.mshcfg.dot11MeshHWMPactivePathTimeout) |
| 73 | #define min_preq_int_jiff(s) \ |
| 74 | (msecs_to_jiffies(s->u.sta.mshcfg.dot11MeshHWMPpreqMinInterval)) |
| 75 | #define max_preq_retries(s) (s->u.sta.mshcfg.dot11MeshHWMPmaxPREQretries) |
| 76 | #define disc_timeout_jiff(s) \ |
| 77 | msecs_to_jiffies(sdata->u.sta.mshcfg.min_discovery_timeout) |
| 78 | |
| 79 | enum mpath_frame_type { |
| 80 | MPATH_PREQ = 0, |
| 81 | MPATH_PREP, |
| 82 | MPATH_PERR |
| 83 | }; |
| 84 | |
| 85 | static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags, |
| 86 | u8 *orig_addr, __le32 orig_dsn, u8 dst_flags, u8 *dst, |
| 87 | __le32 dst_dsn, u8 *da, u8 hop_count, u8 ttl, __le32 lifetime, |
| 88 | __le32 metric, __le32 preq_id, struct net_device *dev) |
| 89 | { |
| 90 | struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); |
| 91 | struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400); |
| 92 | struct ieee80211_mgmt *mgmt; |
| 93 | u8 *pos; |
| 94 | int ie_len; |
| 95 | |
| 96 | if (!skb) |
| 97 | return -1; |
| 98 | skb_reserve(skb, local->hw.extra_tx_headroom); |
| 99 | /* 25 is the size of the common mgmt part (24) plus the size of the |
| 100 | * common action part (1) |
| 101 | */ |
| 102 | mgmt = (struct ieee80211_mgmt *) |
| 103 | skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action)); |
| 104 | memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action)); |
| 105 | mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT, |
| 106 | IEEE80211_STYPE_ACTION); |
| 107 | |
| 108 | memcpy(mgmt->da, da, ETH_ALEN); |
| 109 | memcpy(mgmt->sa, dev->dev_addr, ETH_ALEN); |
| 110 | /* BSSID is left zeroed, wildcard value */ |
| 111 | mgmt->u.action.category = MESH_PATH_SEL_CATEGORY; |
| 112 | mgmt->u.action.u.mesh_action.action_code = action; |
| 113 | |
| 114 | switch (action) { |
| 115 | case MPATH_PREQ: |
| 116 | ie_len = 37; |
| 117 | pos = skb_put(skb, 2 + ie_len); |
| 118 | *pos++ = WLAN_EID_PREQ; |
| 119 | break; |
| 120 | case MPATH_PREP: |
| 121 | ie_len = 31; |
| 122 | pos = skb_put(skb, 2 + ie_len); |
| 123 | *pos++ = WLAN_EID_PREP; |
| 124 | break; |
| 125 | default: |
| 126 | kfree(skb); |
| 127 | return -ENOTSUPP; |
| 128 | break; |
| 129 | } |
| 130 | *pos++ = ie_len; |
| 131 | *pos++ = flags; |
| 132 | *pos++ = hop_count; |
| 133 | *pos++ = ttl; |
| 134 | if (action == MPATH_PREQ) { |
| 135 | memcpy(pos, &preq_id, 4); |
| 136 | pos += 4; |
| 137 | } |
| 138 | memcpy(pos, orig_addr, ETH_ALEN); |
| 139 | pos += ETH_ALEN; |
| 140 | memcpy(pos, &orig_dsn, 4); |
| 141 | pos += 4; |
| 142 | memcpy(pos, &lifetime, 4); |
| 143 | pos += 4; |
| 144 | memcpy(pos, &metric, 4); |
| 145 | pos += 4; |
| 146 | if (action == MPATH_PREQ) { |
| 147 | /* destination count */ |
| 148 | *pos++ = 1; |
| 149 | *pos++ = dst_flags; |
| 150 | } |
| 151 | memcpy(pos, dst, ETH_ALEN); |
| 152 | pos += ETH_ALEN; |
| 153 | memcpy(pos, &dst_dsn, 4); |
| 154 | |
| 155 | ieee80211_sta_tx(dev, skb, 0); |
| 156 | return 0; |
| 157 | } |
| 158 | |
| 159 | /** |
| 160 | * mesh_send_path error - Sends a PERR mesh management frame |
| 161 | * |
| 162 | * @dst: broken destination |
| 163 | * @dst_dsn: dsn of the broken destination |
| 164 | * @ra: node this frame is addressed to |
| 165 | */ |
| 166 | int mesh_path_error_tx(u8 *dst, __le32 dst_dsn, u8 *ra, |
| 167 | struct net_device *dev) |
| 168 | { |
| 169 | struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); |
| 170 | struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400); |
| 171 | struct ieee80211_mgmt *mgmt; |
| 172 | u8 *pos; |
| 173 | int ie_len; |
| 174 | |
| 175 | if (!skb) |
| 176 | return -1; |
| 177 | skb_reserve(skb, local->hw.extra_tx_headroom); |
| 178 | /* 25 is the size of the common mgmt part (24) plus the size of the |
| 179 | * common action part (1) |
| 180 | */ |
| 181 | mgmt = (struct ieee80211_mgmt *) |
| 182 | skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action)); |
| 183 | memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action)); |
| 184 | mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT, |
| 185 | IEEE80211_STYPE_ACTION); |
| 186 | |
| 187 | memcpy(mgmt->da, ra, ETH_ALEN); |
| 188 | memcpy(mgmt->sa, dev->dev_addr, ETH_ALEN); |
| 189 | /* BSSID is left zeroed, wildcard value */ |
| 190 | mgmt->u.action.category = MESH_PATH_SEL_CATEGORY; |
| 191 | mgmt->u.action.u.mesh_action.action_code = MPATH_PERR; |
| 192 | ie_len = 12; |
| 193 | pos = skb_put(skb, 2 + ie_len); |
| 194 | *pos++ = WLAN_EID_PERR; |
| 195 | *pos++ = ie_len; |
| 196 | /* mode flags, reserved */ |
| 197 | *pos++ = 0; |
| 198 | /* number of destinations */ |
| 199 | *pos++ = 1; |
| 200 | memcpy(pos, dst, ETH_ALEN); |
| 201 | pos += ETH_ALEN; |
| 202 | memcpy(pos, &dst_dsn, 4); |
| 203 | |
| 204 | ieee80211_sta_tx(dev, skb, 0); |
| 205 | return 0; |
| 206 | } |
| 207 | |
| 208 | static u32 airtime_link_metric_get(struct ieee80211_local *local, |
| 209 | struct sta_info *sta) |
| 210 | { |
| 211 | struct ieee80211_supported_band *sband; |
| 212 | /* This should be adjusted for each device */ |
| 213 | int device_constant = 1 << ARITH_SHIFT; |
| 214 | int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; |
| 215 | int s_unit = 1 << ARITH_SHIFT; |
| 216 | int rate, err; |
| 217 | u32 tx_time, estimated_retx; |
| 218 | u64 result; |
| 219 | |
| 220 | sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; |
| 221 | |
| 222 | if (sta->fail_avg >= 100) |
| 223 | return MAX_METRIC; |
| 224 | err = (sta->fail_avg << ARITH_SHIFT) / 100; |
| 225 | |
| 226 | /* bitrate is in units of 100 Kbps, while we need rate in units of |
| 227 | * 1Mbps. This will be corrected on tx_time computation. |
| 228 | */ |
| 229 | rate = sband->bitrates[sta->txrate_idx].bitrate; |
| 230 | tx_time = (device_constant + 10 * test_frame_len / rate); |
| 231 | estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); |
| 232 | result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ; |
| 233 | return (u32)result; |
| 234 | } |
| 235 | |
| 236 | /** |
| 237 | * hwmp_route_info_get - Update routing info to originator and transmitter |
| 238 | * |
| 239 | * @dev: local mesh interface |
| 240 | * @mgmt: mesh management frame |
| 241 | * @hwmp_ie: hwmp information element (PREP or PREQ) |
| 242 | * |
| 243 | * This function updates the path routing information to the originator and the |
| 244 | * transmitter of a HWMP PREQ or PREP fram. |
| 245 | * |
| 246 | * Returns: metric to frame originator or 0 if the frame should not be further |
| 247 | * processed |
| 248 | * |
| 249 | * Notes: this function is the only place (besides user-provided info) where |
| 250 | * path routing information is updated. |
| 251 | */ |
| 252 | static u32 hwmp_route_info_get(struct net_device *dev, |
| 253 | struct ieee80211_mgmt *mgmt, |
| 254 | u8 *hwmp_ie) |
| 255 | { |
| 256 | struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); |
| 257 | struct mesh_path *mpath; |
| 258 | struct sta_info *sta; |
| 259 | bool fresh_info; |
| 260 | u8 *orig_addr, *ta; |
| 261 | u32 orig_dsn, orig_metric; |
| 262 | unsigned long orig_lifetime, exp_time; |
| 263 | u32 last_hop_metric, new_metric; |
| 264 | bool process = true; |
| 265 | u8 action = mgmt->u.action.u.mesh_action.action_code; |
| 266 | |
| 267 | rcu_read_lock(); |
| 268 | sta = sta_info_get(local, mgmt->sa); |
Johannes Berg | dc0b0f7 | 2008-02-23 15:17:20 +0100 | [diff] [blame] | 269 | if (!sta) { |
| 270 | rcu_read_unlock(); |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 271 | return 0; |
Johannes Berg | dc0b0f7 | 2008-02-23 15:17:20 +0100 | [diff] [blame] | 272 | } |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 273 | |
| 274 | last_hop_metric = airtime_link_metric_get(local, sta); |
| 275 | /* Update and check originator routing info */ |
| 276 | fresh_info = true; |
| 277 | |
| 278 | switch (action) { |
| 279 | case MPATH_PREQ: |
| 280 | orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); |
| 281 | orig_dsn = PREQ_IE_ORIG_DSN(hwmp_ie); |
| 282 | orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); |
| 283 | orig_metric = PREQ_IE_METRIC(hwmp_ie); |
| 284 | break; |
| 285 | case MPATH_PREP: |
| 286 | /* Originator here refers to the MP that was the destination in |
| 287 | * the Path Request. The draft refers to that MP as the |
| 288 | * destination address, even though usually it is the origin of |
| 289 | * the PREP frame. We divert from the nomenclature in the draft |
| 290 | * so that we can easily use a single function to gather path |
| 291 | * information from both PREQ and PREP frames. |
| 292 | */ |
| 293 | orig_addr = PREP_IE_ORIG_ADDR(hwmp_ie); |
| 294 | orig_dsn = PREP_IE_ORIG_DSN(hwmp_ie); |
| 295 | orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); |
| 296 | orig_metric = PREP_IE_METRIC(hwmp_ie); |
| 297 | break; |
| 298 | default: |
Johannes Berg | dc0b0f7 | 2008-02-23 15:17:20 +0100 | [diff] [blame] | 299 | rcu_read_unlock(); |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 300 | return 0; |
| 301 | } |
| 302 | new_metric = orig_metric + last_hop_metric; |
| 303 | if (new_metric < orig_metric) |
| 304 | new_metric = MAX_METRIC; |
| 305 | exp_time = TU_TO_EXP_TIME(orig_lifetime); |
| 306 | |
| 307 | if (memcmp(orig_addr, dev->dev_addr, ETH_ALEN) == 0) { |
| 308 | /* This MP is the originator, we are not interested in this |
| 309 | * frame, except for updating transmitter's path info. |
| 310 | */ |
| 311 | process = false; |
| 312 | fresh_info = false; |
| 313 | } else { |
| 314 | mpath = mesh_path_lookup(orig_addr, dev); |
| 315 | if (mpath) { |
| 316 | spin_lock_bh(&mpath->state_lock); |
| 317 | if (mpath->flags & MESH_PATH_FIXED) |
| 318 | fresh_info = false; |
| 319 | else if ((mpath->flags & MESH_PATH_ACTIVE) && |
| 320 | (mpath->flags & MESH_PATH_DSN_VALID)) { |
| 321 | if (DSN_GT(mpath->dsn, orig_dsn) || |
| 322 | (mpath->dsn == orig_dsn && |
| 323 | action == MPATH_PREQ && |
| 324 | new_metric > mpath->metric)) { |
| 325 | process = false; |
| 326 | fresh_info = false; |
| 327 | } |
| 328 | } |
| 329 | } else { |
| 330 | mesh_path_add(orig_addr, dev); |
| 331 | mpath = mesh_path_lookup(orig_addr, dev); |
| 332 | if (!mpath) { |
| 333 | rcu_read_unlock(); |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 334 | return 0; |
| 335 | } |
| 336 | spin_lock_bh(&mpath->state_lock); |
| 337 | } |
| 338 | |
| 339 | if (fresh_info) { |
| 340 | mesh_path_assign_nexthop(mpath, sta); |
| 341 | mpath->flags |= MESH_PATH_DSN_VALID; |
| 342 | mpath->metric = new_metric; |
| 343 | mpath->dsn = orig_dsn; |
| 344 | mpath->exp_time = time_after(mpath->exp_time, exp_time) |
| 345 | ? mpath->exp_time : exp_time; |
| 346 | mesh_path_activate(mpath); |
| 347 | spin_unlock_bh(&mpath->state_lock); |
| 348 | mesh_path_tx_pending(mpath); |
| 349 | /* draft says preq_id should be saved to, but there does |
| 350 | * not seem to be any use for it, skipping by now |
| 351 | */ |
| 352 | } else |
| 353 | spin_unlock_bh(&mpath->state_lock); |
| 354 | } |
| 355 | |
| 356 | /* Update and check transmitter routing info */ |
| 357 | ta = mgmt->sa; |
| 358 | if (memcmp(orig_addr, ta, ETH_ALEN) == 0) |
| 359 | fresh_info = false; |
| 360 | else { |
| 361 | fresh_info = true; |
| 362 | |
| 363 | mpath = mesh_path_lookup(ta, dev); |
| 364 | if (mpath) { |
| 365 | spin_lock_bh(&mpath->state_lock); |
| 366 | if ((mpath->flags & MESH_PATH_FIXED) || |
| 367 | ((mpath->flags & MESH_PATH_ACTIVE) && |
| 368 | (last_hop_metric > mpath->metric))) |
| 369 | fresh_info = false; |
| 370 | } else { |
| 371 | mesh_path_add(ta, dev); |
| 372 | mpath = mesh_path_lookup(ta, dev); |
| 373 | if (!mpath) { |
| 374 | rcu_read_unlock(); |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 375 | return 0; |
| 376 | } |
| 377 | spin_lock_bh(&mpath->state_lock); |
| 378 | } |
| 379 | |
| 380 | if (fresh_info) { |
| 381 | mesh_path_assign_nexthop(mpath, sta); |
| 382 | mpath->flags &= ~MESH_PATH_DSN_VALID; |
| 383 | mpath->metric = last_hop_metric; |
| 384 | mpath->exp_time = time_after(mpath->exp_time, exp_time) |
| 385 | ? mpath->exp_time : exp_time; |
| 386 | mesh_path_activate(mpath); |
| 387 | spin_unlock_bh(&mpath->state_lock); |
| 388 | mesh_path_tx_pending(mpath); |
| 389 | } else |
| 390 | spin_unlock_bh(&mpath->state_lock); |
| 391 | } |
| 392 | |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 393 | rcu_read_unlock(); |
| 394 | |
| 395 | return process ? new_metric : 0; |
| 396 | } |
| 397 | |
| 398 | static void hwmp_preq_frame_process(struct net_device *dev, |
| 399 | struct ieee80211_mgmt *mgmt, |
| 400 | u8 *preq_elem, u32 metric) { |
| 401 | struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); |
| 402 | struct ieee80211_if_sta *ifsta = &sdata->u.sta; |
| 403 | struct mesh_path *mpath; |
| 404 | u8 *dst_addr, *orig_addr; |
| 405 | u8 dst_flags, ttl; |
| 406 | u32 orig_dsn, dst_dsn, lifetime; |
| 407 | bool reply = false; |
| 408 | bool forward = true; |
| 409 | |
| 410 | /* Update destination DSN, if present */ |
| 411 | dst_addr = PREQ_IE_DST_ADDR(preq_elem); |
| 412 | orig_addr = PREQ_IE_ORIG_ADDR(preq_elem); |
| 413 | dst_dsn = PREQ_IE_DST_DSN(preq_elem); |
| 414 | orig_dsn = PREQ_IE_ORIG_DSN(preq_elem); |
| 415 | dst_flags = PREQ_IE_DST_F(preq_elem); |
| 416 | |
| 417 | if (memcmp(dst_addr, dev->dev_addr, ETH_ALEN) == 0) { |
| 418 | forward = false; |
| 419 | reply = true; |
| 420 | metric = 0; |
| 421 | if (time_after(jiffies, ifsta->last_dsn_update + |
| 422 | net_traversal_jiffies(sdata)) || |
| 423 | time_before(jiffies, ifsta->last_dsn_update)) { |
| 424 | dst_dsn = ++ifsta->dsn; |
| 425 | ifsta->last_dsn_update = jiffies; |
| 426 | } |
| 427 | } else { |
| 428 | rcu_read_lock(); |
| 429 | mpath = mesh_path_lookup(dst_addr, dev); |
| 430 | if (mpath) { |
| 431 | if ((!(mpath->flags & MESH_PATH_DSN_VALID)) || |
| 432 | DSN_LT(mpath->dsn, dst_dsn)) { |
| 433 | mpath->dsn = dst_dsn; |
| 434 | mpath->flags &= MESH_PATH_DSN_VALID; |
| 435 | } else if ((!(dst_flags & MP_F_DO)) && |
| 436 | (mpath->flags & MESH_PATH_ACTIVE)) { |
| 437 | reply = true; |
| 438 | metric = mpath->metric; |
| 439 | dst_dsn = mpath->dsn; |
| 440 | if (dst_flags & MP_F_RF) |
| 441 | dst_flags |= MP_F_DO; |
| 442 | else |
| 443 | forward = false; |
| 444 | } |
| 445 | } |
| 446 | rcu_read_unlock(); |
| 447 | } |
| 448 | |
| 449 | if (reply) { |
| 450 | lifetime = PREQ_IE_LIFETIME(preq_elem); |
| 451 | ttl = ifsta->mshcfg.dot11MeshTTL; |
| 452 | if (ttl != 0) |
| 453 | mesh_path_sel_frame_tx(MPATH_PREP, 0, dst_addr, |
Luis Carlos Cobo | aa2b592 | 2008-02-29 14:30:32 -0800 | [diff] [blame] | 454 | cpu_to_le32(dst_dsn), 0, orig_addr, |
| 455 | cpu_to_le32(orig_dsn), mgmt->sa, 0, ttl, |
| 456 | cpu_to_le32(lifetime), cpu_to_le32(metric), |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 457 | 0, dev); |
| 458 | else |
| 459 | ifsta->mshstats.dropped_frames_ttl++; |
| 460 | } |
| 461 | |
| 462 | if (forward) { |
| 463 | u32 preq_id; |
| 464 | u8 hopcount, flags; |
| 465 | |
| 466 | ttl = PREQ_IE_TTL(preq_elem); |
| 467 | lifetime = PREQ_IE_LIFETIME(preq_elem); |
| 468 | if (ttl <= 1) { |
| 469 | ifsta->mshstats.dropped_frames_ttl++; |
| 470 | return; |
| 471 | } |
| 472 | --ttl; |
| 473 | flags = PREQ_IE_FLAGS(preq_elem); |
| 474 | preq_id = PREQ_IE_PREQ_ID(preq_elem); |
| 475 | hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; |
| 476 | mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, |
Luis Carlos Cobo | aa2b592 | 2008-02-29 14:30:32 -0800 | [diff] [blame] | 477 | cpu_to_le32(orig_dsn), dst_flags, dst_addr, |
| 478 | cpu_to_le32(dst_dsn), dev->broadcast, |
| 479 | hopcount, ttl, cpu_to_le32(lifetime), |
| 480 | cpu_to_le32(metric), cpu_to_le32(preq_id), |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 481 | dev); |
| 482 | ifsta->mshstats.fwded_frames++; |
| 483 | } |
| 484 | } |
| 485 | |
| 486 | |
| 487 | static void hwmp_prep_frame_process(struct net_device *dev, |
| 488 | struct ieee80211_mgmt *mgmt, |
| 489 | u8 *prep_elem, u32 metric) |
| 490 | { |
| 491 | struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); |
| 492 | struct mesh_path *mpath; |
| 493 | u8 *dst_addr, *orig_addr; |
| 494 | u8 ttl, hopcount, flags; |
| 495 | u8 next_hop[ETH_ALEN]; |
| 496 | u32 dst_dsn, orig_dsn, lifetime; |
| 497 | |
| 498 | /* Note that we divert from the draft nomenclature and denominate |
| 499 | * destination to what the draft refers to as origininator. So in this |
| 500 | * function destnation refers to the final destination of the PREP, |
| 501 | * which corresponds with the originator of the PREQ which this PREP |
| 502 | * replies |
| 503 | */ |
| 504 | dst_addr = PREP_IE_DST_ADDR(prep_elem); |
| 505 | if (memcmp(dst_addr, dev->dev_addr, ETH_ALEN) == 0) |
| 506 | /* destination, no forwarding required */ |
| 507 | return; |
| 508 | |
| 509 | ttl = PREP_IE_TTL(prep_elem); |
| 510 | if (ttl <= 1) { |
| 511 | sdata->u.sta.mshstats.dropped_frames_ttl++; |
| 512 | return; |
| 513 | } |
| 514 | |
| 515 | rcu_read_lock(); |
| 516 | mpath = mesh_path_lookup(dst_addr, dev); |
| 517 | if (mpath) |
| 518 | spin_lock_bh(&mpath->state_lock); |
| 519 | else |
| 520 | goto fail; |
| 521 | if (!(mpath->flags & MESH_PATH_ACTIVE)) { |
| 522 | spin_unlock_bh(&mpath->state_lock); |
| 523 | goto fail; |
| 524 | } |
| 525 | memcpy(next_hop, mpath->next_hop->addr, ETH_ALEN); |
| 526 | spin_unlock_bh(&mpath->state_lock); |
| 527 | --ttl; |
| 528 | flags = PREP_IE_FLAGS(prep_elem); |
| 529 | lifetime = PREP_IE_LIFETIME(prep_elem); |
| 530 | hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1; |
| 531 | orig_addr = PREP_IE_ORIG_ADDR(prep_elem); |
| 532 | dst_dsn = PREP_IE_DST_DSN(prep_elem); |
| 533 | orig_dsn = PREP_IE_ORIG_DSN(prep_elem); |
| 534 | |
| 535 | mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, |
Luis Carlos Cobo | aa2b592 | 2008-02-29 14:30:32 -0800 | [diff] [blame] | 536 | cpu_to_le32(orig_dsn), 0, dst_addr, |
| 537 | cpu_to_le32(dst_dsn), mpath->next_hop->addr, hopcount, ttl, |
| 538 | cpu_to_le32(lifetime), cpu_to_le32(metric), |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 539 | 0, dev); |
| 540 | rcu_read_unlock(); |
| 541 | sdata->u.sta.mshstats.fwded_frames++; |
| 542 | return; |
| 543 | |
| 544 | fail: |
| 545 | rcu_read_unlock(); |
| 546 | sdata->u.sta.mshstats.dropped_frames_no_route++; |
| 547 | return; |
| 548 | } |
| 549 | |
| 550 | static void hwmp_perr_frame_process(struct net_device *dev, |
| 551 | struct ieee80211_mgmt *mgmt, u8 *perr_elem) |
| 552 | { |
| 553 | struct mesh_path *mpath; |
| 554 | u8 *ta, *dst_addr; |
| 555 | u32 dst_dsn; |
| 556 | |
| 557 | ta = mgmt->sa; |
| 558 | dst_addr = PERR_IE_DST_ADDR(perr_elem); |
| 559 | dst_dsn = PERR_IE_DST_DSN(perr_elem); |
| 560 | rcu_read_lock(); |
| 561 | mpath = mesh_path_lookup(dst_addr, dev); |
| 562 | if (mpath) { |
| 563 | spin_lock_bh(&mpath->state_lock); |
| 564 | if (mpath->flags & MESH_PATH_ACTIVE && |
| 565 | memcmp(ta, mpath->next_hop->addr, ETH_ALEN) == 0 && |
| 566 | (!(mpath->flags & MESH_PATH_DSN_VALID) || |
| 567 | DSN_GT(dst_dsn, mpath->dsn))) { |
| 568 | mpath->flags &= ~MESH_PATH_ACTIVE; |
| 569 | mpath->dsn = dst_dsn; |
| 570 | spin_unlock_bh(&mpath->state_lock); |
Luis Carlos Cobo | aa2b592 | 2008-02-29 14:30:32 -0800 | [diff] [blame] | 571 | mesh_path_error_tx(dst_addr, cpu_to_le32(dst_dsn), |
Luis Carlos Cobo | 37659ff | 2008-02-29 12:13:38 -0800 | [diff] [blame] | 572 | dev->broadcast, dev); |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 573 | } else |
| 574 | spin_unlock_bh(&mpath->state_lock); |
| 575 | } |
| 576 | rcu_read_unlock(); |
| 577 | } |
| 578 | |
| 579 | |
| 580 | |
| 581 | void mesh_rx_path_sel_frame(struct net_device *dev, |
| 582 | struct ieee80211_mgmt *mgmt, |
| 583 | size_t len) |
| 584 | { |
| 585 | struct ieee802_11_elems elems; |
| 586 | size_t baselen; |
| 587 | u32 last_hop_metric; |
| 588 | |
| 589 | baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; |
| 590 | ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, |
| 591 | len - baselen, &elems); |
| 592 | |
| 593 | switch (mgmt->u.action.u.mesh_action.action_code) { |
| 594 | case MPATH_PREQ: |
| 595 | if (!elems.preq || elems.preq_len != 37) |
| 596 | /* Right now we support just 1 destination and no AE */ |
| 597 | return; |
| 598 | last_hop_metric = hwmp_route_info_get(dev, mgmt, elems.preq); |
| 599 | if (!last_hop_metric) |
| 600 | return; |
| 601 | hwmp_preq_frame_process(dev, mgmt, elems.preq, last_hop_metric); |
| 602 | break; |
| 603 | case MPATH_PREP: |
| 604 | if (!elems.prep || elems.prep_len != 31) |
| 605 | /* Right now we support no AE */ |
| 606 | return; |
| 607 | last_hop_metric = hwmp_route_info_get(dev, mgmt, elems.prep); |
| 608 | if (!last_hop_metric) |
| 609 | return; |
| 610 | hwmp_prep_frame_process(dev, mgmt, elems.prep, last_hop_metric); |
| 611 | break; |
| 612 | case MPATH_PERR: |
| 613 | if (!elems.perr || elems.perr_len != 12) |
| 614 | /* Right now we support only one destination per PERR */ |
| 615 | return; |
| 616 | hwmp_perr_frame_process(dev, mgmt, elems.perr); |
| 617 | default: |
| 618 | return; |
| 619 | } |
| 620 | |
| 621 | } |
| 622 | |
| 623 | /** |
| 624 | * mesh_queue_preq - queue a PREQ to a given destination |
| 625 | * |
| 626 | * @mpath: mesh path to discover |
| 627 | * @flags: special attributes of the PREQ to be sent |
| 628 | * |
| 629 | * Locking: the function must be called from within a rcu read lock block. |
| 630 | * |
| 631 | */ |
| 632 | static void mesh_queue_preq(struct mesh_path *mpath, u8 flags) |
| 633 | { |
| 634 | struct ieee80211_sub_if_data *sdata = |
| 635 | IEEE80211_DEV_TO_SUB_IF(mpath->dev); |
| 636 | struct ieee80211_if_sta *ifsta = &sdata->u.sta; |
| 637 | struct mesh_preq_queue *preq_node; |
| 638 | |
| 639 | preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_KERNEL); |
| 640 | if (!preq_node) { |
| 641 | printk(KERN_DEBUG "Mesh HWMP: could not allocate PREQ node\n"); |
| 642 | return; |
| 643 | } |
| 644 | |
| 645 | spin_lock(&ifsta->mesh_preq_queue_lock); |
| 646 | if (ifsta->preq_queue_len == MAX_PREQ_QUEUE_LEN) { |
| 647 | spin_unlock(&ifsta->mesh_preq_queue_lock); |
| 648 | kfree(preq_node); |
| 649 | if (printk_ratelimit()) |
| 650 | printk(KERN_DEBUG "Mesh HWMP: PREQ node queue full\n"); |
| 651 | return; |
| 652 | } |
| 653 | |
| 654 | memcpy(preq_node->dst, mpath->dst, ETH_ALEN); |
| 655 | preq_node->flags = flags; |
| 656 | |
| 657 | list_add_tail(&preq_node->list, &ifsta->preq_queue.list); |
| 658 | ++ifsta->preq_queue_len; |
| 659 | spin_unlock(&ifsta->mesh_preq_queue_lock); |
| 660 | |
| 661 | if (time_after(jiffies, ifsta->last_preq + min_preq_int_jiff(sdata))) |
| 662 | queue_work(sdata->local->hw.workqueue, &ifsta->work); |
| 663 | |
| 664 | else if (time_before(jiffies, ifsta->last_preq)) { |
| 665 | /* avoid long wait if did not send preqs for a long time |
| 666 | * and jiffies wrapped around |
| 667 | */ |
| 668 | ifsta->last_preq = jiffies - min_preq_int_jiff(sdata) - 1; |
| 669 | queue_work(sdata->local->hw.workqueue, &ifsta->work); |
| 670 | } else |
| 671 | mod_timer(&ifsta->mesh_path_timer, ifsta->last_preq + |
| 672 | min_preq_int_jiff(sdata)); |
| 673 | } |
| 674 | |
| 675 | /** |
| 676 | * mesh_path_start_discovery - launch a path discovery from the PREQ queue |
| 677 | * |
| 678 | * @dev: local mesh interface |
| 679 | */ |
| 680 | void mesh_path_start_discovery(struct net_device *dev) |
| 681 | { |
| 682 | struct ieee80211_sub_if_data *sdata = |
| 683 | IEEE80211_DEV_TO_SUB_IF(dev); |
| 684 | struct ieee80211_if_sta *ifsta = &sdata->u.sta; |
| 685 | struct mesh_preq_queue *preq_node; |
| 686 | struct mesh_path *mpath; |
| 687 | u8 ttl, dst_flags; |
| 688 | u32 lifetime; |
| 689 | |
| 690 | spin_lock(&ifsta->mesh_preq_queue_lock); |
| 691 | if (!ifsta->preq_queue_len || |
| 692 | time_before(jiffies, ifsta->last_preq + |
| 693 | min_preq_int_jiff(sdata))) { |
| 694 | spin_unlock(&ifsta->mesh_preq_queue_lock); |
| 695 | return; |
| 696 | } |
| 697 | |
| 698 | preq_node = list_first_entry(&ifsta->preq_queue.list, |
| 699 | struct mesh_preq_queue, list); |
| 700 | list_del(&preq_node->list); |
| 701 | --ifsta->preq_queue_len; |
| 702 | spin_unlock(&ifsta->mesh_preq_queue_lock); |
| 703 | |
| 704 | rcu_read_lock(); |
| 705 | mpath = mesh_path_lookup(preq_node->dst, dev); |
| 706 | if (!mpath) |
| 707 | goto enddiscovery; |
| 708 | |
| 709 | spin_lock_bh(&mpath->state_lock); |
| 710 | if (preq_node->flags & PREQ_Q_F_START) { |
| 711 | if (mpath->flags & MESH_PATH_RESOLVING) { |
| 712 | spin_unlock_bh(&mpath->state_lock); |
| 713 | goto enddiscovery; |
| 714 | } else { |
| 715 | mpath->flags &= ~MESH_PATH_RESOLVED; |
| 716 | mpath->flags |= MESH_PATH_RESOLVING; |
| 717 | mpath->discovery_retries = 0; |
| 718 | mpath->discovery_timeout = disc_timeout_jiff(sdata); |
| 719 | } |
| 720 | } else if (!(mpath->flags & MESH_PATH_RESOLVING) || |
| 721 | mpath->flags & MESH_PATH_RESOLVED) { |
| 722 | mpath->flags &= ~MESH_PATH_RESOLVING; |
| 723 | spin_unlock_bh(&mpath->state_lock); |
| 724 | goto enddiscovery; |
| 725 | } |
| 726 | |
| 727 | ifsta->last_preq = jiffies; |
| 728 | |
| 729 | if (time_after(jiffies, ifsta->last_dsn_update + |
| 730 | net_traversal_jiffies(sdata)) || |
| 731 | time_before(jiffies, ifsta->last_dsn_update)) { |
| 732 | ++ifsta->dsn; |
| 733 | sdata->u.sta.last_dsn_update = jiffies; |
| 734 | } |
| 735 | lifetime = default_lifetime(sdata); |
| 736 | ttl = sdata->u.sta.mshcfg.dot11MeshTTL; |
| 737 | if (ttl == 0) { |
| 738 | sdata->u.sta.mshstats.dropped_frames_ttl++; |
| 739 | spin_unlock_bh(&mpath->state_lock); |
| 740 | goto enddiscovery; |
| 741 | } |
| 742 | |
| 743 | if (preq_node->flags & PREQ_Q_F_REFRESH) |
| 744 | dst_flags = MP_F_DO; |
| 745 | else |
| 746 | dst_flags = MP_F_RF; |
| 747 | |
| 748 | spin_unlock_bh(&mpath->state_lock); |
| 749 | mesh_path_sel_frame_tx(MPATH_PREQ, 0, dev->dev_addr, |
Luis Carlos Cobo | aa2b592 | 2008-02-29 14:30:32 -0800 | [diff] [blame] | 750 | cpu_to_le32(ifsta->dsn), dst_flags, mpath->dst, |
| 751 | cpu_to_le32(mpath->dsn), dev->broadcast, 0, |
| 752 | ttl, cpu_to_le32(lifetime), 0, |
| 753 | cpu_to_le32(ifsta->preq_id++), dev); |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 754 | mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); |
| 755 | |
| 756 | enddiscovery: |
| 757 | rcu_read_unlock(); |
| 758 | kfree(preq_node); |
| 759 | } |
| 760 | |
| 761 | /** |
| 762 | * ieee80211s_lookup_nexthop - put the appropriate next hop on a mesh frame |
| 763 | * |
| 764 | * @next_hop: output argument for next hop address |
| 765 | * @skb: frame to be sent |
| 766 | * @dev: network device the frame will be sent through |
| 767 | * |
| 768 | * Returns: 0 if the next hop was found. Nonzero otherwise. If no next hop is |
| 769 | * found, the function will start a path discovery and queue the frame so it is |
| 770 | * sent when the path is resolved. This means the caller must not free the skb |
| 771 | * in this case. |
| 772 | */ |
| 773 | int mesh_nexthop_lookup(u8 *next_hop, struct sk_buff *skb, |
| 774 | struct net_device *dev) |
| 775 | { |
| 776 | struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); |
| 777 | struct sk_buff *skb_to_free = NULL; |
| 778 | struct mesh_path *mpath; |
| 779 | int err = 0; |
| 780 | |
| 781 | rcu_read_lock(); |
| 782 | mpath = mesh_path_lookup(skb->data, dev); |
| 783 | |
| 784 | if (!mpath) { |
| 785 | mesh_path_add(skb->data, dev); |
| 786 | mpath = mesh_path_lookup(skb->data, dev); |
| 787 | if (!mpath) { |
| 788 | dev_kfree_skb(skb); |
| 789 | sdata->u.sta.mshstats.dropped_frames_no_route++; |
| 790 | err = -ENOSPC; |
| 791 | goto endlookup; |
| 792 | } |
| 793 | } |
| 794 | |
| 795 | if (mpath->flags & MESH_PATH_ACTIVE) { |
| 796 | if (time_after(jiffies, mpath->exp_time - |
| 797 | msecs_to_jiffies(sdata->u.sta.mshcfg.path_refresh_time)) |
| 798 | && skb->pkt_type != PACKET_OTHERHOST |
| 799 | && !(mpath->flags & MESH_PATH_RESOLVING) |
| 800 | && !(mpath->flags & MESH_PATH_FIXED)) { |
| 801 | mesh_queue_preq(mpath, |
| 802 | PREQ_Q_F_START | PREQ_Q_F_REFRESH); |
| 803 | } |
| 804 | memcpy(next_hop, mpath->next_hop->addr, |
| 805 | ETH_ALEN); |
| 806 | } else { |
| 807 | if (!(mpath->flags & MESH_PATH_RESOLVING)) { |
| 808 | /* Start discovery only if it is not running yet */ |
| 809 | mesh_queue_preq(mpath, PREQ_Q_F_START); |
| 810 | } |
| 811 | |
| 812 | if (skb_queue_len(&mpath->frame_queue) >= |
| 813 | MESH_FRAME_QUEUE_LEN) { |
| 814 | skb_to_free = mpath->frame_queue.next; |
| 815 | skb_unlink(skb_to_free, &mpath->frame_queue); |
| 816 | } |
| 817 | |
| 818 | skb_queue_tail(&mpath->frame_queue, skb); |
| 819 | if (skb_to_free) |
| 820 | mesh_path_discard_frame(skb_to_free, dev); |
| 821 | err = -ENOENT; |
| 822 | } |
| 823 | |
| 824 | endlookup: |
| 825 | rcu_read_unlock(); |
| 826 | return err; |
| 827 | } |
| 828 | |
| 829 | void mesh_path_timer(unsigned long data) |
| 830 | { |
| 831 | struct ieee80211_sub_if_data *sdata; |
| 832 | struct mesh_path *mpath; |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 833 | |
| 834 | rcu_read_lock(); |
| 835 | mpath = (struct mesh_path *) data; |
| 836 | mpath = rcu_dereference(mpath); |
| 837 | if (!mpath) |
| 838 | goto endmpathtimer; |
| 839 | spin_lock_bh(&mpath->state_lock); |
| 840 | sdata = IEEE80211_DEV_TO_SUB_IF(mpath->dev); |
Luis Carlos Cobo | cfa22c7 | 2008-02-29 15:04:13 -0800 | [diff] [blame] | 841 | if (mpath->flags & MESH_PATH_RESOLVED || |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 842 | (!(mpath->flags & MESH_PATH_RESOLVING))) |
| 843 | mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED); |
| 844 | else if (mpath->discovery_retries < max_preq_retries(sdata)) { |
| 845 | ++mpath->discovery_retries; |
| 846 | mpath->discovery_timeout *= 2; |
| 847 | mesh_queue_preq(mpath, 0); |
| 848 | } else { |
| 849 | mpath->flags = 0; |
| 850 | mpath->exp_time = jiffies; |
| 851 | mesh_path_flush_pending(mpath); |
| 852 | } |
| 853 | |
| 854 | spin_unlock_bh(&mpath->state_lock); |
| 855 | endmpathtimer: |
| 856 | rcu_read_unlock(); |
Luis Carlos Cobo | 050ac52 | 2008-02-23 15:17:15 +0100 | [diff] [blame] | 857 | } |