| 1 | /* |
| 2 | * Copyright (c) 2008, 2009 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 | |
| 10 | #include <linux/slab.h> |
| 11 | #include <linux/etherdevice.h> |
| 12 | #include <asm/unaligned.h> |
| 13 | #include "wme.h" |
| 14 | #include "mesh.h" |
| 15 | |
| 16 | #define TEST_FRAME_LEN 8192 |
| 17 | #define MAX_METRIC 0xffffffff |
| 18 | #define ARITH_SHIFT 8 |
| 19 | |
| 20 | #define MAX_PREQ_QUEUE_LEN 64 |
| 21 | |
| 22 | /* Destination only */ |
| 23 | #define MP_F_DO 0x1 |
| 24 | /* Reply and forward */ |
| 25 | #define MP_F_RF 0x2 |
| 26 | /* Unknown Sequence Number */ |
| 27 | #define MP_F_USN 0x01 |
| 28 | /* Reason code Present */ |
| 29 | #define MP_F_RCODE 0x02 |
| 30 | |
| 31 | static void mesh_queue_preq(struct mesh_path *, u8); |
| 32 | |
| 33 | static inline u32 u32_field_get(u8 *preq_elem, int offset, bool ae) |
| 34 | { |
| 35 | if (ae) |
| 36 | offset += 6; |
| 37 | return get_unaligned_le32(preq_elem + offset); |
| 38 | } |
| 39 | |
| 40 | static inline u32 u16_field_get(u8 *preq_elem, int offset, bool ae) |
| 41 | { |
| 42 | if (ae) |
| 43 | offset += 6; |
| 44 | return get_unaligned_le16(preq_elem + offset); |
| 45 | } |
| 46 | |
| 47 | /* HWMP IE processing macros */ |
| 48 | #define AE_F (1<<6) |
| 49 | #define AE_F_SET(x) (*x & AE_F) |
| 50 | #define PREQ_IE_FLAGS(x) (*(x)) |
| 51 | #define PREQ_IE_HOPCOUNT(x) (*(x + 1)) |
| 52 | #define PREQ_IE_TTL(x) (*(x + 2)) |
| 53 | #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0) |
| 54 | #define PREQ_IE_ORIG_ADDR(x) (x + 7) |
| 55 | #define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0) |
| 56 | #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x)) |
| 57 | #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x)) |
| 58 | #define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26)) |
| 59 | #define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27) |
| 60 | #define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x)) |
| 61 | |
| 62 | |
| 63 | #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x) |
| 64 | #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x) |
| 65 | #define PREP_IE_TTL(x) PREQ_IE_TTL(x) |
| 66 | #define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21) |
| 67 | #define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x)) |
| 68 | #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x)) |
| 69 | #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x)) |
| 70 | #define PREP_IE_TARGET_ADDR(x) (x + 3) |
| 71 | #define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0) |
| 72 | |
| 73 | #define PERR_IE_TTL(x) (*(x)) |
| 74 | #define PERR_IE_TARGET_FLAGS(x) (*(x + 2)) |
| 75 | #define PERR_IE_TARGET_ADDR(x) (x + 3) |
| 76 | #define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0) |
| 77 | #define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0) |
| 78 | |
| 79 | #define MSEC_TO_TU(x) (x*1000/1024) |
| 80 | #define SN_GT(x, y) ((s32)(y - x) < 0) |
| 81 | #define SN_LT(x, y) ((s32)(x - y) < 0) |
| 82 | |
| 83 | #define net_traversal_jiffies(s) \ |
| 84 | msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime) |
| 85 | #define default_lifetime(s) \ |
| 86 | MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout) |
| 87 | #define min_preq_int_jiff(s) \ |
| 88 | (msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval)) |
| 89 | #define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries) |
| 90 | #define disc_timeout_jiff(s) \ |
| 91 | msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout) |
| 92 | #define root_path_confirmation_jiffies(s) \ |
| 93 | msecs_to_jiffies(sdata->u.mesh.mshcfg.dot11MeshHWMPconfirmationInterval) |
| 94 | |
| 95 | enum mpath_frame_type { |
| 96 | MPATH_PREQ = 0, |
| 97 | MPATH_PREP, |
| 98 | MPATH_PERR, |
| 99 | MPATH_RANN |
| 100 | }; |
| 101 | |
| 102 | static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; |
| 103 | |
| 104 | static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags, |
| 105 | u8 *orig_addr, __le32 orig_sn, u8 target_flags, u8 *target, |
| 106 | __le32 target_sn, const u8 *da, u8 hop_count, u8 ttl, |
| 107 | __le32 lifetime, __le32 metric, __le32 preq_id, |
| 108 | struct ieee80211_sub_if_data *sdata) |
| 109 | { |
| 110 | struct ieee80211_local *local = sdata->local; |
| 111 | struct sk_buff *skb; |
| 112 | struct ieee80211_mgmt *mgmt; |
| 113 | u8 *pos, ie_len; |
| 114 | int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + |
| 115 | sizeof(mgmt->u.action.u.mesh_action); |
| 116 | |
| 117 | skb = dev_alloc_skb(local->tx_headroom + |
| 118 | hdr_len + |
| 119 | 2 + 37); /* max HWMP IE */ |
| 120 | if (!skb) |
| 121 | return -1; |
| 122 | skb_reserve(skb, local->tx_headroom); |
| 123 | mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); |
| 124 | memset(mgmt, 0, hdr_len); |
| 125 | mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | |
| 126 | IEEE80211_STYPE_ACTION); |
| 127 | |
| 128 | memcpy(mgmt->da, da, ETH_ALEN); |
| 129 | memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); |
| 130 | /* BSSID == SA */ |
| 131 | memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); |
| 132 | mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; |
| 133 | mgmt->u.action.u.mesh_action.action_code = |
| 134 | WLAN_MESH_ACTION_HWMP_PATH_SELECTION; |
| 135 | |
| 136 | switch (action) { |
| 137 | case MPATH_PREQ: |
| 138 | mhwmp_dbg(sdata, "sending PREQ to %pM\n", target); |
| 139 | ie_len = 37; |
| 140 | pos = skb_put(skb, 2 + ie_len); |
| 141 | *pos++ = WLAN_EID_PREQ; |
| 142 | break; |
| 143 | case MPATH_PREP: |
| 144 | mhwmp_dbg(sdata, "sending PREP to %pM\n", target); |
| 145 | ie_len = 31; |
| 146 | pos = skb_put(skb, 2 + ie_len); |
| 147 | *pos++ = WLAN_EID_PREP; |
| 148 | break; |
| 149 | case MPATH_RANN: |
| 150 | mhwmp_dbg(sdata, "sending RANN from %pM\n", orig_addr); |
| 151 | ie_len = sizeof(struct ieee80211_rann_ie); |
| 152 | pos = skb_put(skb, 2 + ie_len); |
| 153 | *pos++ = WLAN_EID_RANN; |
| 154 | break; |
| 155 | default: |
| 156 | kfree_skb(skb); |
| 157 | return -ENOTSUPP; |
| 158 | break; |
| 159 | } |
| 160 | *pos++ = ie_len; |
| 161 | *pos++ = flags; |
| 162 | *pos++ = hop_count; |
| 163 | *pos++ = ttl; |
| 164 | if (action == MPATH_PREP) { |
| 165 | memcpy(pos, target, ETH_ALEN); |
| 166 | pos += ETH_ALEN; |
| 167 | memcpy(pos, &target_sn, 4); |
| 168 | pos += 4; |
| 169 | } else { |
| 170 | if (action == MPATH_PREQ) { |
| 171 | memcpy(pos, &preq_id, 4); |
| 172 | pos += 4; |
| 173 | } |
| 174 | memcpy(pos, orig_addr, ETH_ALEN); |
| 175 | pos += ETH_ALEN; |
| 176 | memcpy(pos, &orig_sn, 4); |
| 177 | pos += 4; |
| 178 | } |
| 179 | memcpy(pos, &lifetime, 4); /* interval for RANN */ |
| 180 | pos += 4; |
| 181 | memcpy(pos, &metric, 4); |
| 182 | pos += 4; |
| 183 | if (action == MPATH_PREQ) { |
| 184 | *pos++ = 1; /* destination count */ |
| 185 | *pos++ = target_flags; |
| 186 | memcpy(pos, target, ETH_ALEN); |
| 187 | pos += ETH_ALEN; |
| 188 | memcpy(pos, &target_sn, 4); |
| 189 | pos += 4; |
| 190 | } else if (action == MPATH_PREP) { |
| 191 | memcpy(pos, orig_addr, ETH_ALEN); |
| 192 | pos += ETH_ALEN; |
| 193 | memcpy(pos, &orig_sn, 4); |
| 194 | pos += 4; |
| 195 | } |
| 196 | |
| 197 | ieee80211_tx_skb(sdata, skb); |
| 198 | return 0; |
| 199 | } |
| 200 | |
| 201 | |
| 202 | /* Headroom is not adjusted. Caller should ensure that skb has sufficient |
| 203 | * headroom in case the frame is encrypted. */ |
| 204 | static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata, |
| 205 | struct sk_buff *skb) |
| 206 | { |
| 207 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
| 208 | |
| 209 | skb_set_mac_header(skb, 0); |
| 210 | skb_set_network_header(skb, 0); |
| 211 | skb_set_transport_header(skb, 0); |
| 212 | |
| 213 | /* Send all internal mgmt frames on VO. Accordingly set TID to 7. */ |
| 214 | skb_set_queue_mapping(skb, IEEE80211_AC_VO); |
| 215 | skb->priority = 7; |
| 216 | |
| 217 | info->control.vif = &sdata->vif; |
| 218 | ieee80211_set_qos_hdr(sdata, skb); |
| 219 | } |
| 220 | |
| 221 | /** |
| 222 | * mesh_send_path error - Sends a PERR mesh management frame |
| 223 | * |
| 224 | * @target: broken destination |
| 225 | * @target_sn: SN of the broken destination |
| 226 | * @target_rcode: reason code for this PERR |
| 227 | * @ra: node this frame is addressed to |
| 228 | * |
| 229 | * Note: This function may be called with driver locks taken that the driver |
| 230 | * also acquires in the TX path. To avoid a deadlock we don't transmit the |
| 231 | * frame directly but add it to the pending queue instead. |
| 232 | */ |
| 233 | int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn, |
| 234 | __le16 target_rcode, const u8 *ra, |
| 235 | struct ieee80211_sub_if_data *sdata) |
| 236 | { |
| 237 | struct ieee80211_local *local = sdata->local; |
| 238 | struct sk_buff *skb; |
| 239 | struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| 240 | struct ieee80211_mgmt *mgmt; |
| 241 | u8 *pos, ie_len; |
| 242 | int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + |
| 243 | sizeof(mgmt->u.action.u.mesh_action); |
| 244 | |
| 245 | if (time_before(jiffies, ifmsh->next_perr)) |
| 246 | return -EAGAIN; |
| 247 | |
| 248 | skb = dev_alloc_skb(local->tx_headroom + |
| 249 | hdr_len + |
| 250 | 2 + 15 /* PERR IE */); |
| 251 | if (!skb) |
| 252 | return -1; |
| 253 | skb_reserve(skb, local->tx_headroom); |
| 254 | mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); |
| 255 | memset(mgmt, 0, hdr_len); |
| 256 | mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | |
| 257 | IEEE80211_STYPE_ACTION); |
| 258 | |
| 259 | memcpy(mgmt->da, ra, ETH_ALEN); |
| 260 | memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); |
| 261 | /* BSSID == SA */ |
| 262 | memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); |
| 263 | mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; |
| 264 | mgmt->u.action.u.mesh_action.action_code = |
| 265 | WLAN_MESH_ACTION_HWMP_PATH_SELECTION; |
| 266 | ie_len = 15; |
| 267 | pos = skb_put(skb, 2 + ie_len); |
| 268 | *pos++ = WLAN_EID_PERR; |
| 269 | *pos++ = ie_len; |
| 270 | /* ttl */ |
| 271 | *pos++ = ttl; |
| 272 | /* number of destinations */ |
| 273 | *pos++ = 1; |
| 274 | /* |
| 275 | * flags bit, bit 1 is unset if we know the sequence number and |
| 276 | * bit 2 is set if we have a reason code |
| 277 | */ |
| 278 | *pos = 0; |
| 279 | if (!target_sn) |
| 280 | *pos |= MP_F_USN; |
| 281 | if (target_rcode) |
| 282 | *pos |= MP_F_RCODE; |
| 283 | pos++; |
| 284 | memcpy(pos, target, ETH_ALEN); |
| 285 | pos += ETH_ALEN; |
| 286 | memcpy(pos, &target_sn, 4); |
| 287 | pos += 4; |
| 288 | memcpy(pos, &target_rcode, 2); |
| 289 | |
| 290 | /* see note in function header */ |
| 291 | prepare_frame_for_deferred_tx(sdata, skb); |
| 292 | ifmsh->next_perr = TU_TO_EXP_TIME( |
| 293 | ifmsh->mshcfg.dot11MeshHWMPperrMinInterval); |
| 294 | ieee80211_add_pending_skb(local, skb); |
| 295 | return 0; |
| 296 | } |
| 297 | |
| 298 | void ieee80211s_update_metric(struct ieee80211_local *local, |
| 299 | struct sta_info *sta, struct sk_buff *skb) |
| 300 | { |
| 301 | struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb); |
| 302 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| 303 | int failed; |
| 304 | |
| 305 | if (!ieee80211_is_data(hdr->frame_control)) |
| 306 | return; |
| 307 | |
| 308 | failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK); |
| 309 | |
| 310 | /* moving average, scaled to 100 */ |
| 311 | sta->fail_avg = ((80 * sta->fail_avg + 5) / 100 + 20 * failed); |
| 312 | if (sta->fail_avg > 95) |
| 313 | mesh_plink_broken(sta); |
| 314 | } |
| 315 | |
| 316 | static u32 airtime_link_metric_get(struct ieee80211_local *local, |
| 317 | struct sta_info *sta) |
| 318 | { |
| 319 | struct rate_info rinfo; |
| 320 | /* This should be adjusted for each device */ |
| 321 | int device_constant = 1 << ARITH_SHIFT; |
| 322 | int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; |
| 323 | int s_unit = 1 << ARITH_SHIFT; |
| 324 | int rate, err; |
| 325 | u32 tx_time, estimated_retx; |
| 326 | u64 result; |
| 327 | |
| 328 | if (sta->fail_avg >= 100) |
| 329 | return MAX_METRIC; |
| 330 | |
| 331 | sta_set_rate_info_tx(sta, &sta->last_tx_rate, &rinfo); |
| 332 | rate = cfg80211_calculate_bitrate(&rinfo); |
| 333 | if (WARN_ON(!rate)) |
| 334 | return MAX_METRIC; |
| 335 | |
| 336 | err = (sta->fail_avg << ARITH_SHIFT) / 100; |
| 337 | |
| 338 | /* bitrate is in units of 100 Kbps, while we need rate in units of |
| 339 | * 1Mbps. This will be corrected on tx_time computation. |
| 340 | */ |
| 341 | tx_time = (device_constant + 10 * test_frame_len / rate); |
| 342 | estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); |
| 343 | result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ; |
| 344 | return (u32)result; |
| 345 | } |
| 346 | |
| 347 | /** |
| 348 | * hwmp_route_info_get - Update routing info to originator and transmitter |
| 349 | * |
| 350 | * @sdata: local mesh subif |
| 351 | * @mgmt: mesh management frame |
| 352 | * @hwmp_ie: hwmp information element (PREP or PREQ) |
| 353 | * |
| 354 | * This function updates the path routing information to the originator and the |
| 355 | * transmitter of a HWMP PREQ or PREP frame. |
| 356 | * |
| 357 | * Returns: metric to frame originator or 0 if the frame should not be further |
| 358 | * processed |
| 359 | * |
| 360 | * Notes: this function is the only place (besides user-provided info) where |
| 361 | * path routing information is updated. |
| 362 | */ |
| 363 | static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata, |
| 364 | struct ieee80211_mgmt *mgmt, |
| 365 | u8 *hwmp_ie, enum mpath_frame_type action) |
| 366 | { |
| 367 | struct ieee80211_local *local = sdata->local; |
| 368 | struct mesh_path *mpath; |
| 369 | struct sta_info *sta; |
| 370 | bool fresh_info; |
| 371 | u8 *orig_addr, *ta; |
| 372 | u32 orig_sn, orig_metric; |
| 373 | unsigned long orig_lifetime, exp_time; |
| 374 | u32 last_hop_metric, new_metric; |
| 375 | bool process = true; |
| 376 | |
| 377 | rcu_read_lock(); |
| 378 | sta = sta_info_get(sdata, mgmt->sa); |
| 379 | if (!sta) { |
| 380 | rcu_read_unlock(); |
| 381 | return 0; |
| 382 | } |
| 383 | |
| 384 | last_hop_metric = airtime_link_metric_get(local, sta); |
| 385 | /* Update and check originator routing info */ |
| 386 | fresh_info = true; |
| 387 | |
| 388 | switch (action) { |
| 389 | case MPATH_PREQ: |
| 390 | orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); |
| 391 | orig_sn = PREQ_IE_ORIG_SN(hwmp_ie); |
| 392 | orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); |
| 393 | orig_metric = PREQ_IE_METRIC(hwmp_ie); |
| 394 | break; |
| 395 | case MPATH_PREP: |
| 396 | /* Originator here refers to the MP that was the target in the |
| 397 | * Path Request. We divert from the nomenclature in the draft |
| 398 | * so that we can easily use a single function to gather path |
| 399 | * information from both PREQ and PREP frames. |
| 400 | */ |
| 401 | orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie); |
| 402 | orig_sn = PREP_IE_TARGET_SN(hwmp_ie); |
| 403 | orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); |
| 404 | orig_metric = PREP_IE_METRIC(hwmp_ie); |
| 405 | break; |
| 406 | default: |
| 407 | rcu_read_unlock(); |
| 408 | return 0; |
| 409 | } |
| 410 | new_metric = orig_metric + last_hop_metric; |
| 411 | if (new_metric < orig_metric) |
| 412 | new_metric = MAX_METRIC; |
| 413 | exp_time = TU_TO_EXP_TIME(orig_lifetime); |
| 414 | |
| 415 | if (ether_addr_equal(orig_addr, sdata->vif.addr)) { |
| 416 | /* This MP is the originator, we are not interested in this |
| 417 | * frame, except for updating transmitter's path info. |
| 418 | */ |
| 419 | process = false; |
| 420 | fresh_info = false; |
| 421 | } else { |
| 422 | mpath = mesh_path_lookup(orig_addr, sdata); |
| 423 | if (mpath) { |
| 424 | spin_lock_bh(&mpath->state_lock); |
| 425 | if (mpath->flags & MESH_PATH_FIXED) |
| 426 | fresh_info = false; |
| 427 | else if ((mpath->flags & MESH_PATH_ACTIVE) && |
| 428 | (mpath->flags & MESH_PATH_SN_VALID)) { |
| 429 | if (SN_GT(mpath->sn, orig_sn) || |
| 430 | (mpath->sn == orig_sn && |
| 431 | new_metric >= mpath->metric)) { |
| 432 | process = false; |
| 433 | fresh_info = false; |
| 434 | } |
| 435 | } |
| 436 | } else { |
| 437 | mesh_path_add(orig_addr, sdata); |
| 438 | mpath = mesh_path_lookup(orig_addr, sdata); |
| 439 | if (!mpath) { |
| 440 | rcu_read_unlock(); |
| 441 | return 0; |
| 442 | } |
| 443 | spin_lock_bh(&mpath->state_lock); |
| 444 | } |
| 445 | |
| 446 | if (fresh_info) { |
| 447 | mesh_path_assign_nexthop(mpath, sta); |
| 448 | mpath->flags |= MESH_PATH_SN_VALID; |
| 449 | mpath->metric = new_metric; |
| 450 | mpath->sn = orig_sn; |
| 451 | mpath->exp_time = time_after(mpath->exp_time, exp_time) |
| 452 | ? mpath->exp_time : exp_time; |
| 453 | mesh_path_activate(mpath); |
| 454 | spin_unlock_bh(&mpath->state_lock); |
| 455 | mesh_path_tx_pending(mpath); |
| 456 | /* draft says preq_id should be saved to, but there does |
| 457 | * not seem to be any use for it, skipping by now |
| 458 | */ |
| 459 | } else |
| 460 | spin_unlock_bh(&mpath->state_lock); |
| 461 | } |
| 462 | |
| 463 | /* Update and check transmitter routing info */ |
| 464 | ta = mgmt->sa; |
| 465 | if (ether_addr_equal(orig_addr, ta)) |
| 466 | fresh_info = false; |
| 467 | else { |
| 468 | fresh_info = true; |
| 469 | |
| 470 | mpath = mesh_path_lookup(ta, sdata); |
| 471 | if (mpath) { |
| 472 | spin_lock_bh(&mpath->state_lock); |
| 473 | if ((mpath->flags & MESH_PATH_FIXED) || |
| 474 | ((mpath->flags & MESH_PATH_ACTIVE) && |
| 475 | (last_hop_metric > mpath->metric))) |
| 476 | fresh_info = false; |
| 477 | } else { |
| 478 | mesh_path_add(ta, sdata); |
| 479 | mpath = mesh_path_lookup(ta, sdata); |
| 480 | if (!mpath) { |
| 481 | rcu_read_unlock(); |
| 482 | return 0; |
| 483 | } |
| 484 | spin_lock_bh(&mpath->state_lock); |
| 485 | } |
| 486 | |
| 487 | if (fresh_info) { |
| 488 | mesh_path_assign_nexthop(mpath, sta); |
| 489 | mpath->metric = last_hop_metric; |
| 490 | mpath->exp_time = time_after(mpath->exp_time, exp_time) |
| 491 | ? mpath->exp_time : exp_time; |
| 492 | mesh_path_activate(mpath); |
| 493 | spin_unlock_bh(&mpath->state_lock); |
| 494 | mesh_path_tx_pending(mpath); |
| 495 | } else |
| 496 | spin_unlock_bh(&mpath->state_lock); |
| 497 | } |
| 498 | |
| 499 | rcu_read_unlock(); |
| 500 | |
| 501 | return process ? new_metric : 0; |
| 502 | } |
| 503 | |
| 504 | static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata, |
| 505 | struct ieee80211_mgmt *mgmt, |
| 506 | u8 *preq_elem, u32 metric) |
| 507 | { |
| 508 | struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| 509 | struct mesh_path *mpath = NULL; |
| 510 | u8 *target_addr, *orig_addr; |
| 511 | const u8 *da; |
| 512 | u8 target_flags, ttl, flags; |
| 513 | u32 orig_sn, target_sn, lifetime, orig_metric; |
| 514 | bool reply = false; |
| 515 | bool forward = true; |
| 516 | bool root_is_gate; |
| 517 | |
| 518 | /* Update target SN, if present */ |
| 519 | target_addr = PREQ_IE_TARGET_ADDR(preq_elem); |
| 520 | orig_addr = PREQ_IE_ORIG_ADDR(preq_elem); |
| 521 | target_sn = PREQ_IE_TARGET_SN(preq_elem); |
| 522 | orig_sn = PREQ_IE_ORIG_SN(preq_elem); |
| 523 | target_flags = PREQ_IE_TARGET_F(preq_elem); |
| 524 | orig_metric = metric; |
| 525 | /* Proactive PREQ gate announcements */ |
| 526 | flags = PREQ_IE_FLAGS(preq_elem); |
| 527 | root_is_gate = !!(flags & RANN_FLAG_IS_GATE); |
| 528 | |
| 529 | mhwmp_dbg(sdata, "received PREQ from %pM\n", orig_addr); |
| 530 | |
| 531 | if (ether_addr_equal(target_addr, sdata->vif.addr)) { |
| 532 | mhwmp_dbg(sdata, "PREQ is for us\n"); |
| 533 | forward = false; |
| 534 | reply = true; |
| 535 | metric = 0; |
| 536 | if (time_after(jiffies, ifmsh->last_sn_update + |
| 537 | net_traversal_jiffies(sdata)) || |
| 538 | time_before(jiffies, ifmsh->last_sn_update)) { |
| 539 | target_sn = ++ifmsh->sn; |
| 540 | ifmsh->last_sn_update = jiffies; |
| 541 | } |
| 542 | } else if (is_broadcast_ether_addr(target_addr) && |
| 543 | (target_flags & IEEE80211_PREQ_TO_FLAG)) { |
| 544 | rcu_read_lock(); |
| 545 | mpath = mesh_path_lookup(orig_addr, sdata); |
| 546 | if (mpath) { |
| 547 | if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { |
| 548 | reply = true; |
| 549 | target_addr = sdata->vif.addr; |
| 550 | target_sn = ++ifmsh->sn; |
| 551 | metric = 0; |
| 552 | ifmsh->last_sn_update = jiffies; |
| 553 | } |
| 554 | if (root_is_gate) |
| 555 | mesh_path_add_gate(mpath); |
| 556 | } |
| 557 | rcu_read_unlock(); |
| 558 | } else { |
| 559 | rcu_read_lock(); |
| 560 | mpath = mesh_path_lookup(target_addr, sdata); |
| 561 | if (mpath) { |
| 562 | if ((!(mpath->flags & MESH_PATH_SN_VALID)) || |
| 563 | SN_LT(mpath->sn, target_sn)) { |
| 564 | mpath->sn = target_sn; |
| 565 | mpath->flags |= MESH_PATH_SN_VALID; |
| 566 | } else if ((!(target_flags & MP_F_DO)) && |
| 567 | (mpath->flags & MESH_PATH_ACTIVE)) { |
| 568 | reply = true; |
| 569 | metric = mpath->metric; |
| 570 | target_sn = mpath->sn; |
| 571 | if (target_flags & MP_F_RF) |
| 572 | target_flags |= MP_F_DO; |
| 573 | else |
| 574 | forward = false; |
| 575 | } |
| 576 | } |
| 577 | rcu_read_unlock(); |
| 578 | } |
| 579 | |
| 580 | if (reply) { |
| 581 | lifetime = PREQ_IE_LIFETIME(preq_elem); |
| 582 | ttl = ifmsh->mshcfg.element_ttl; |
| 583 | if (ttl != 0) { |
| 584 | mhwmp_dbg(sdata, "replying to the PREQ\n"); |
| 585 | mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr, |
| 586 | cpu_to_le32(orig_sn), 0, target_addr, |
| 587 | cpu_to_le32(target_sn), mgmt->sa, 0, ttl, |
| 588 | cpu_to_le32(lifetime), cpu_to_le32(metric), |
| 589 | 0, sdata); |
| 590 | } else { |
| 591 | ifmsh->mshstats.dropped_frames_ttl++; |
| 592 | } |
| 593 | } |
| 594 | |
| 595 | if (forward && ifmsh->mshcfg.dot11MeshForwarding) { |
| 596 | u32 preq_id; |
| 597 | u8 hopcount; |
| 598 | |
| 599 | ttl = PREQ_IE_TTL(preq_elem); |
| 600 | lifetime = PREQ_IE_LIFETIME(preq_elem); |
| 601 | if (ttl <= 1) { |
| 602 | ifmsh->mshstats.dropped_frames_ttl++; |
| 603 | return; |
| 604 | } |
| 605 | mhwmp_dbg(sdata, "forwarding the PREQ from %pM\n", orig_addr); |
| 606 | --ttl; |
| 607 | preq_id = PREQ_IE_PREQ_ID(preq_elem); |
| 608 | hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; |
| 609 | da = (mpath && mpath->is_root) ? |
| 610 | mpath->rann_snd_addr : broadcast_addr; |
| 611 | |
| 612 | if (flags & IEEE80211_PREQ_PROACTIVE_PREP_FLAG) { |
| 613 | target_addr = PREQ_IE_TARGET_ADDR(preq_elem); |
| 614 | target_sn = PREQ_IE_TARGET_SN(preq_elem); |
| 615 | metric = orig_metric; |
| 616 | } |
| 617 | |
| 618 | mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, |
| 619 | cpu_to_le32(orig_sn), target_flags, target_addr, |
| 620 | cpu_to_le32(target_sn), da, |
| 621 | hopcount, ttl, cpu_to_le32(lifetime), |
| 622 | cpu_to_le32(metric), cpu_to_le32(preq_id), |
| 623 | sdata); |
| 624 | if (!is_multicast_ether_addr(da)) |
| 625 | ifmsh->mshstats.fwded_unicast++; |
| 626 | else |
| 627 | ifmsh->mshstats.fwded_mcast++; |
| 628 | ifmsh->mshstats.fwded_frames++; |
| 629 | } |
| 630 | } |
| 631 | |
| 632 | |
| 633 | static inline struct sta_info * |
| 634 | next_hop_deref_protected(struct mesh_path *mpath) |
| 635 | { |
| 636 | return rcu_dereference_protected(mpath->next_hop, |
| 637 | lockdep_is_held(&mpath->state_lock)); |
| 638 | } |
| 639 | |
| 640 | |
| 641 | static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata, |
| 642 | struct ieee80211_mgmt *mgmt, |
| 643 | u8 *prep_elem, u32 metric) |
| 644 | { |
| 645 | struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| 646 | struct mesh_path *mpath; |
| 647 | u8 *target_addr, *orig_addr; |
| 648 | u8 ttl, hopcount, flags; |
| 649 | u8 next_hop[ETH_ALEN]; |
| 650 | u32 target_sn, orig_sn, lifetime; |
| 651 | |
| 652 | mhwmp_dbg(sdata, "received PREP from %pM\n", |
| 653 | PREP_IE_ORIG_ADDR(prep_elem)); |
| 654 | |
| 655 | orig_addr = PREP_IE_ORIG_ADDR(prep_elem); |
| 656 | if (ether_addr_equal(orig_addr, sdata->vif.addr)) |
| 657 | /* destination, no forwarding required */ |
| 658 | return; |
| 659 | |
| 660 | if (!ifmsh->mshcfg.dot11MeshForwarding) |
| 661 | return; |
| 662 | |
| 663 | ttl = PREP_IE_TTL(prep_elem); |
| 664 | if (ttl <= 1) { |
| 665 | sdata->u.mesh.mshstats.dropped_frames_ttl++; |
| 666 | return; |
| 667 | } |
| 668 | |
| 669 | rcu_read_lock(); |
| 670 | mpath = mesh_path_lookup(orig_addr, sdata); |
| 671 | if (mpath) |
| 672 | spin_lock_bh(&mpath->state_lock); |
| 673 | else |
| 674 | goto fail; |
| 675 | if (!(mpath->flags & MESH_PATH_ACTIVE)) { |
| 676 | spin_unlock_bh(&mpath->state_lock); |
| 677 | goto fail; |
| 678 | } |
| 679 | memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN); |
| 680 | spin_unlock_bh(&mpath->state_lock); |
| 681 | --ttl; |
| 682 | flags = PREP_IE_FLAGS(prep_elem); |
| 683 | lifetime = PREP_IE_LIFETIME(prep_elem); |
| 684 | hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1; |
| 685 | target_addr = PREP_IE_TARGET_ADDR(prep_elem); |
| 686 | target_sn = PREP_IE_TARGET_SN(prep_elem); |
| 687 | orig_sn = PREP_IE_ORIG_SN(prep_elem); |
| 688 | |
| 689 | mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, |
| 690 | cpu_to_le32(orig_sn), 0, target_addr, |
| 691 | cpu_to_le32(target_sn), next_hop, hopcount, |
| 692 | ttl, cpu_to_le32(lifetime), cpu_to_le32(metric), |
| 693 | 0, sdata); |
| 694 | rcu_read_unlock(); |
| 695 | |
| 696 | sdata->u.mesh.mshstats.fwded_unicast++; |
| 697 | sdata->u.mesh.mshstats.fwded_frames++; |
| 698 | return; |
| 699 | |
| 700 | fail: |
| 701 | rcu_read_unlock(); |
| 702 | sdata->u.mesh.mshstats.dropped_frames_no_route++; |
| 703 | } |
| 704 | |
| 705 | static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata, |
| 706 | struct ieee80211_mgmt *mgmt, u8 *perr_elem) |
| 707 | { |
| 708 | struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| 709 | struct mesh_path *mpath; |
| 710 | u8 ttl; |
| 711 | u8 *ta, *target_addr; |
| 712 | u32 target_sn; |
| 713 | u16 target_rcode; |
| 714 | |
| 715 | ta = mgmt->sa; |
| 716 | ttl = PERR_IE_TTL(perr_elem); |
| 717 | if (ttl <= 1) { |
| 718 | ifmsh->mshstats.dropped_frames_ttl++; |
| 719 | return; |
| 720 | } |
| 721 | ttl--; |
| 722 | target_addr = PERR_IE_TARGET_ADDR(perr_elem); |
| 723 | target_sn = PERR_IE_TARGET_SN(perr_elem); |
| 724 | target_rcode = PERR_IE_TARGET_RCODE(perr_elem); |
| 725 | |
| 726 | rcu_read_lock(); |
| 727 | mpath = mesh_path_lookup(target_addr, sdata); |
| 728 | if (mpath) { |
| 729 | struct sta_info *sta; |
| 730 | |
| 731 | spin_lock_bh(&mpath->state_lock); |
| 732 | sta = next_hop_deref_protected(mpath); |
| 733 | if (mpath->flags & MESH_PATH_ACTIVE && |
| 734 | ether_addr_equal(ta, sta->sta.addr) && |
| 735 | (!(mpath->flags & MESH_PATH_SN_VALID) || |
| 736 | SN_GT(target_sn, mpath->sn))) { |
| 737 | mpath->flags &= ~MESH_PATH_ACTIVE; |
| 738 | mpath->sn = target_sn; |
| 739 | spin_unlock_bh(&mpath->state_lock); |
| 740 | if (!ifmsh->mshcfg.dot11MeshForwarding) |
| 741 | goto endperr; |
| 742 | mesh_path_error_tx(ttl, target_addr, cpu_to_le32(target_sn), |
| 743 | cpu_to_le16(target_rcode), |
| 744 | broadcast_addr, sdata); |
| 745 | } else |
| 746 | spin_unlock_bh(&mpath->state_lock); |
| 747 | } |
| 748 | endperr: |
| 749 | rcu_read_unlock(); |
| 750 | } |
| 751 | |
| 752 | static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata, |
| 753 | struct ieee80211_mgmt *mgmt, |
| 754 | struct ieee80211_rann_ie *rann) |
| 755 | { |
| 756 | struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| 757 | struct ieee80211_local *local = sdata->local; |
| 758 | struct sta_info *sta; |
| 759 | struct mesh_path *mpath; |
| 760 | u8 ttl, flags, hopcount; |
| 761 | u8 *orig_addr; |
| 762 | u32 orig_sn, metric, metric_txsta, interval; |
| 763 | bool root_is_gate; |
| 764 | |
| 765 | ttl = rann->rann_ttl; |
| 766 | flags = rann->rann_flags; |
| 767 | root_is_gate = !!(flags & RANN_FLAG_IS_GATE); |
| 768 | orig_addr = rann->rann_addr; |
| 769 | orig_sn = le32_to_cpu(rann->rann_seq); |
| 770 | interval = le32_to_cpu(rann->rann_interval); |
| 771 | hopcount = rann->rann_hopcount; |
| 772 | hopcount++; |
| 773 | metric = le32_to_cpu(rann->rann_metric); |
| 774 | |
| 775 | /* Ignore our own RANNs */ |
| 776 | if (ether_addr_equal(orig_addr, sdata->vif.addr)) |
| 777 | return; |
| 778 | |
| 779 | mhwmp_dbg(sdata, |
| 780 | "received RANN from %pM via neighbour %pM (is_gate=%d)\n", |
| 781 | orig_addr, mgmt->sa, root_is_gate); |
| 782 | |
| 783 | rcu_read_lock(); |
| 784 | sta = sta_info_get(sdata, mgmt->sa); |
| 785 | if (!sta) { |
| 786 | rcu_read_unlock(); |
| 787 | return; |
| 788 | } |
| 789 | |
| 790 | metric_txsta = airtime_link_metric_get(local, sta); |
| 791 | |
| 792 | mpath = mesh_path_lookup(orig_addr, sdata); |
| 793 | if (!mpath) { |
| 794 | mesh_path_add(orig_addr, sdata); |
| 795 | mpath = mesh_path_lookup(orig_addr, sdata); |
| 796 | if (!mpath) { |
| 797 | rcu_read_unlock(); |
| 798 | sdata->u.mesh.mshstats.dropped_frames_no_route++; |
| 799 | return; |
| 800 | } |
| 801 | } |
| 802 | |
| 803 | if (!(SN_LT(mpath->sn, orig_sn)) && |
| 804 | !(mpath->sn == orig_sn && metric < mpath->rann_metric)) { |
| 805 | rcu_read_unlock(); |
| 806 | return; |
| 807 | } |
| 808 | |
| 809 | if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) || |
| 810 | (time_after(jiffies, mpath->last_preq_to_root + |
| 811 | root_path_confirmation_jiffies(sdata)) || |
| 812 | time_before(jiffies, mpath->last_preq_to_root))) && |
| 813 | !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) { |
| 814 | mhwmp_dbg(sdata, |
| 815 | "time to refresh root mpath %pM\n", |
| 816 | orig_addr); |
| 817 | mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); |
| 818 | mpath->last_preq_to_root = jiffies; |
| 819 | } |
| 820 | |
| 821 | mpath->sn = orig_sn; |
| 822 | mpath->rann_metric = metric + metric_txsta; |
| 823 | mpath->is_root = true; |
| 824 | /* Recording RANNs sender address to send individually |
| 825 | * addressed PREQs destined for root mesh STA */ |
| 826 | memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN); |
| 827 | |
| 828 | if (root_is_gate) |
| 829 | mesh_path_add_gate(mpath); |
| 830 | |
| 831 | if (ttl <= 1) { |
| 832 | ifmsh->mshstats.dropped_frames_ttl++; |
| 833 | rcu_read_unlock(); |
| 834 | return; |
| 835 | } |
| 836 | ttl--; |
| 837 | |
| 838 | if (ifmsh->mshcfg.dot11MeshForwarding) { |
| 839 | mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr, |
| 840 | cpu_to_le32(orig_sn), |
| 841 | 0, NULL, 0, broadcast_addr, |
| 842 | hopcount, ttl, cpu_to_le32(interval), |
| 843 | cpu_to_le32(metric + metric_txsta), |
| 844 | 0, sdata); |
| 845 | } |
| 846 | |
| 847 | rcu_read_unlock(); |
| 848 | } |
| 849 | |
| 850 | |
| 851 | void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata, |
| 852 | struct ieee80211_mgmt *mgmt, |
| 853 | size_t len) |
| 854 | { |
| 855 | struct ieee802_11_elems elems; |
| 856 | size_t baselen; |
| 857 | u32 last_hop_metric; |
| 858 | struct sta_info *sta; |
| 859 | |
| 860 | /* need action_code */ |
| 861 | if (len < IEEE80211_MIN_ACTION_SIZE + 1) |
| 862 | return; |
| 863 | |
| 864 | rcu_read_lock(); |
| 865 | sta = sta_info_get(sdata, mgmt->sa); |
| 866 | if (!sta || sta->plink_state != NL80211_PLINK_ESTAB) { |
| 867 | rcu_read_unlock(); |
| 868 | return; |
| 869 | } |
| 870 | rcu_read_unlock(); |
| 871 | |
| 872 | baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; |
| 873 | ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, |
| 874 | len - baselen, &elems); |
| 875 | |
| 876 | if (elems.preq) { |
| 877 | if (elems.preq_len != 37) |
| 878 | /* Right now we support just 1 destination and no AE */ |
| 879 | return; |
| 880 | last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.preq, |
| 881 | MPATH_PREQ); |
| 882 | if (last_hop_metric) |
| 883 | hwmp_preq_frame_process(sdata, mgmt, elems.preq, |
| 884 | last_hop_metric); |
| 885 | } |
| 886 | if (elems.prep) { |
| 887 | if (elems.prep_len != 31) |
| 888 | /* Right now we support no AE */ |
| 889 | return; |
| 890 | last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.prep, |
| 891 | MPATH_PREP); |
| 892 | if (last_hop_metric) |
| 893 | hwmp_prep_frame_process(sdata, mgmt, elems.prep, |
| 894 | last_hop_metric); |
| 895 | } |
| 896 | if (elems.perr) { |
| 897 | if (elems.perr_len != 15) |
| 898 | /* Right now we support only one destination per PERR */ |
| 899 | return; |
| 900 | hwmp_perr_frame_process(sdata, mgmt, elems.perr); |
| 901 | } |
| 902 | if (elems.rann) |
| 903 | hwmp_rann_frame_process(sdata, mgmt, elems.rann); |
| 904 | } |
| 905 | |
| 906 | /** |
| 907 | * mesh_queue_preq - queue a PREQ to a given destination |
| 908 | * |
| 909 | * @mpath: mesh path to discover |
| 910 | * @flags: special attributes of the PREQ to be sent |
| 911 | * |
| 912 | * Locking: the function must be called from within a rcu read lock block. |
| 913 | * |
| 914 | */ |
| 915 | static void mesh_queue_preq(struct mesh_path *mpath, u8 flags) |
| 916 | { |
| 917 | struct ieee80211_sub_if_data *sdata = mpath->sdata; |
| 918 | struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| 919 | struct mesh_preq_queue *preq_node; |
| 920 | |
| 921 | preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC); |
| 922 | if (!preq_node) { |
| 923 | mhwmp_dbg(sdata, "could not allocate PREQ node\n"); |
| 924 | return; |
| 925 | } |
| 926 | |
| 927 | spin_lock_bh(&ifmsh->mesh_preq_queue_lock); |
| 928 | if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) { |
| 929 | spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); |
| 930 | kfree(preq_node); |
| 931 | if (printk_ratelimit()) |
| 932 | mhwmp_dbg(sdata, "PREQ node queue full\n"); |
| 933 | return; |
| 934 | } |
| 935 | |
| 936 | spin_lock(&mpath->state_lock); |
| 937 | if (mpath->flags & MESH_PATH_REQ_QUEUED) { |
| 938 | spin_unlock(&mpath->state_lock); |
| 939 | spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); |
| 940 | kfree(preq_node); |
| 941 | return; |
| 942 | } |
| 943 | |
| 944 | memcpy(preq_node->dst, mpath->dst, ETH_ALEN); |
| 945 | preq_node->flags = flags; |
| 946 | |
| 947 | mpath->flags |= MESH_PATH_REQ_QUEUED; |
| 948 | spin_unlock(&mpath->state_lock); |
| 949 | |
| 950 | list_add_tail(&preq_node->list, &ifmsh->preq_queue.list); |
| 951 | ++ifmsh->preq_queue_len; |
| 952 | spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); |
| 953 | |
| 954 | if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata))) |
| 955 | ieee80211_queue_work(&sdata->local->hw, &sdata->work); |
| 956 | |
| 957 | else if (time_before(jiffies, ifmsh->last_preq)) { |
| 958 | /* avoid long wait if did not send preqs for a long time |
| 959 | * and jiffies wrapped around |
| 960 | */ |
| 961 | ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1; |
| 962 | ieee80211_queue_work(&sdata->local->hw, &sdata->work); |
| 963 | } else |
| 964 | mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq + |
| 965 | min_preq_int_jiff(sdata)); |
| 966 | } |
| 967 | |
| 968 | /** |
| 969 | * mesh_path_start_discovery - launch a path discovery from the PREQ queue |
| 970 | * |
| 971 | * @sdata: local mesh subif |
| 972 | */ |
| 973 | void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata) |
| 974 | { |
| 975 | struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| 976 | struct mesh_preq_queue *preq_node; |
| 977 | struct mesh_path *mpath; |
| 978 | u8 ttl, target_flags; |
| 979 | const u8 *da; |
| 980 | u32 lifetime; |
| 981 | |
| 982 | spin_lock_bh(&ifmsh->mesh_preq_queue_lock); |
| 983 | if (!ifmsh->preq_queue_len || |
| 984 | time_before(jiffies, ifmsh->last_preq + |
| 985 | min_preq_int_jiff(sdata))) { |
| 986 | spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); |
| 987 | return; |
| 988 | } |
| 989 | |
| 990 | preq_node = list_first_entry(&ifmsh->preq_queue.list, |
| 991 | struct mesh_preq_queue, list); |
| 992 | list_del(&preq_node->list); |
| 993 | --ifmsh->preq_queue_len; |
| 994 | spin_unlock_bh(&ifmsh->mesh_preq_queue_lock); |
| 995 | |
| 996 | rcu_read_lock(); |
| 997 | mpath = mesh_path_lookup(preq_node->dst, sdata); |
| 998 | if (!mpath) |
| 999 | goto enddiscovery; |
| 1000 | |
| 1001 | spin_lock_bh(&mpath->state_lock); |
| 1002 | mpath->flags &= ~MESH_PATH_REQ_QUEUED; |
| 1003 | if (preq_node->flags & PREQ_Q_F_START) { |
| 1004 | if (mpath->flags & MESH_PATH_RESOLVING) { |
| 1005 | spin_unlock_bh(&mpath->state_lock); |
| 1006 | goto enddiscovery; |
| 1007 | } else { |
| 1008 | mpath->flags &= ~MESH_PATH_RESOLVED; |
| 1009 | mpath->flags |= MESH_PATH_RESOLVING; |
| 1010 | mpath->discovery_retries = 0; |
| 1011 | mpath->discovery_timeout = disc_timeout_jiff(sdata); |
| 1012 | } |
| 1013 | } else if (!(mpath->flags & MESH_PATH_RESOLVING) || |
| 1014 | mpath->flags & MESH_PATH_RESOLVED) { |
| 1015 | mpath->flags &= ~MESH_PATH_RESOLVING; |
| 1016 | spin_unlock_bh(&mpath->state_lock); |
| 1017 | goto enddiscovery; |
| 1018 | } |
| 1019 | |
| 1020 | ifmsh->last_preq = jiffies; |
| 1021 | |
| 1022 | if (time_after(jiffies, ifmsh->last_sn_update + |
| 1023 | net_traversal_jiffies(sdata)) || |
| 1024 | time_before(jiffies, ifmsh->last_sn_update)) { |
| 1025 | ++ifmsh->sn; |
| 1026 | sdata->u.mesh.last_sn_update = jiffies; |
| 1027 | } |
| 1028 | lifetime = default_lifetime(sdata); |
| 1029 | ttl = sdata->u.mesh.mshcfg.element_ttl; |
| 1030 | if (ttl == 0) { |
| 1031 | sdata->u.mesh.mshstats.dropped_frames_ttl++; |
| 1032 | spin_unlock_bh(&mpath->state_lock); |
| 1033 | goto enddiscovery; |
| 1034 | } |
| 1035 | |
| 1036 | if (preq_node->flags & PREQ_Q_F_REFRESH) |
| 1037 | target_flags = MP_F_DO; |
| 1038 | else |
| 1039 | target_flags = MP_F_RF; |
| 1040 | |
| 1041 | spin_unlock_bh(&mpath->state_lock); |
| 1042 | da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr; |
| 1043 | mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr, |
| 1044 | cpu_to_le32(ifmsh->sn), target_flags, mpath->dst, |
| 1045 | cpu_to_le32(mpath->sn), da, 0, |
| 1046 | ttl, cpu_to_le32(lifetime), 0, |
| 1047 | cpu_to_le32(ifmsh->preq_id++), sdata); |
| 1048 | mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); |
| 1049 | |
| 1050 | enddiscovery: |
| 1051 | rcu_read_unlock(); |
| 1052 | kfree(preq_node); |
| 1053 | } |
| 1054 | |
| 1055 | /** |
| 1056 | * mesh_nexthop_resolve - lookup next hop; conditionally start path discovery |
| 1057 | * |
| 1058 | * @skb: 802.11 frame to be sent |
| 1059 | * @sdata: network subif the frame will be sent through |
| 1060 | * |
| 1061 | * Lookup next hop for given skb and start path discovery if no |
| 1062 | * forwarding information is found. |
| 1063 | * |
| 1064 | * Returns: 0 if the next hop was found and -ENOENT if the frame was queued. |
| 1065 | * skb is freeed here if no mpath could be allocated. |
| 1066 | */ |
| 1067 | int mesh_nexthop_resolve(struct sk_buff *skb, |
| 1068 | struct ieee80211_sub_if_data *sdata) |
| 1069 | { |
| 1070 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| 1071 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
| 1072 | struct mesh_path *mpath; |
| 1073 | struct sk_buff *skb_to_free = NULL; |
| 1074 | u8 *target_addr = hdr->addr3; |
| 1075 | int err = 0; |
| 1076 | |
| 1077 | rcu_read_lock(); |
| 1078 | err = mesh_nexthop_lookup(skb, sdata); |
| 1079 | if (!err) |
| 1080 | goto endlookup; |
| 1081 | |
| 1082 | /* no nexthop found, start resolving */ |
| 1083 | mpath = mesh_path_lookup(target_addr, sdata); |
| 1084 | if (!mpath) { |
| 1085 | mesh_path_add(target_addr, sdata); |
| 1086 | mpath = mesh_path_lookup(target_addr, sdata); |
| 1087 | if (!mpath) { |
| 1088 | mesh_path_discard_frame(skb, sdata); |
| 1089 | err = -ENOSPC; |
| 1090 | goto endlookup; |
| 1091 | } |
| 1092 | } |
| 1093 | |
| 1094 | if (!(mpath->flags & MESH_PATH_RESOLVING)) |
| 1095 | mesh_queue_preq(mpath, PREQ_Q_F_START); |
| 1096 | |
| 1097 | if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN) |
| 1098 | skb_to_free = skb_dequeue(&mpath->frame_queue); |
| 1099 | |
| 1100 | info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; |
| 1101 | ieee80211_set_qos_hdr(sdata, skb); |
| 1102 | skb_queue_tail(&mpath->frame_queue, skb); |
| 1103 | err = -ENOENT; |
| 1104 | if (skb_to_free) |
| 1105 | mesh_path_discard_frame(skb_to_free, sdata); |
| 1106 | |
| 1107 | endlookup: |
| 1108 | rcu_read_unlock(); |
| 1109 | return err; |
| 1110 | } |
| 1111 | /** |
| 1112 | * mesh_nexthop_lookup - put the appropriate next hop on a mesh frame. Calling |
| 1113 | * this function is considered "using" the associated mpath, so preempt a path |
| 1114 | * refresh if this mpath expires soon. |
| 1115 | * |
| 1116 | * @skb: 802.11 frame to be sent |
| 1117 | * @sdata: network subif the frame will be sent through |
| 1118 | * |
| 1119 | * Returns: 0 if the next hop was found. Nonzero otherwise. |
| 1120 | */ |
| 1121 | int mesh_nexthop_lookup(struct sk_buff *skb, |
| 1122 | struct ieee80211_sub_if_data *sdata) |
| 1123 | { |
| 1124 | struct mesh_path *mpath; |
| 1125 | struct sta_info *next_hop; |
| 1126 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| 1127 | u8 *target_addr = hdr->addr3; |
| 1128 | int err = -ENOENT; |
| 1129 | |
| 1130 | rcu_read_lock(); |
| 1131 | mpath = mesh_path_lookup(target_addr, sdata); |
| 1132 | |
| 1133 | if (!mpath || !(mpath->flags & MESH_PATH_ACTIVE)) |
| 1134 | goto endlookup; |
| 1135 | |
| 1136 | if (time_after(jiffies, |
| 1137 | mpath->exp_time - |
| 1138 | msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) && |
| 1139 | ether_addr_equal(sdata->vif.addr, hdr->addr4) && |
| 1140 | !(mpath->flags & MESH_PATH_RESOLVING) && |
| 1141 | !(mpath->flags & MESH_PATH_FIXED)) |
| 1142 | mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); |
| 1143 | |
| 1144 | next_hop = rcu_dereference(mpath->next_hop); |
| 1145 | if (next_hop) { |
| 1146 | memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN); |
| 1147 | memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN); |
| 1148 | err = 0; |
| 1149 | } |
| 1150 | |
| 1151 | endlookup: |
| 1152 | rcu_read_unlock(); |
| 1153 | return err; |
| 1154 | } |
| 1155 | |
| 1156 | void mesh_path_timer(unsigned long data) |
| 1157 | { |
| 1158 | struct mesh_path *mpath = (void *) data; |
| 1159 | struct ieee80211_sub_if_data *sdata = mpath->sdata; |
| 1160 | int ret; |
| 1161 | |
| 1162 | if (sdata->local->quiescing) |
| 1163 | return; |
| 1164 | |
| 1165 | spin_lock_bh(&mpath->state_lock); |
| 1166 | if (mpath->flags & MESH_PATH_RESOLVED || |
| 1167 | (!(mpath->flags & MESH_PATH_RESOLVING))) { |
| 1168 | mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED); |
| 1169 | spin_unlock_bh(&mpath->state_lock); |
| 1170 | } else if (mpath->discovery_retries < max_preq_retries(sdata)) { |
| 1171 | ++mpath->discovery_retries; |
| 1172 | mpath->discovery_timeout *= 2; |
| 1173 | mpath->flags &= ~MESH_PATH_REQ_QUEUED; |
| 1174 | spin_unlock_bh(&mpath->state_lock); |
| 1175 | mesh_queue_preq(mpath, 0); |
| 1176 | } else { |
| 1177 | mpath->flags = 0; |
| 1178 | mpath->exp_time = jiffies; |
| 1179 | spin_unlock_bh(&mpath->state_lock); |
| 1180 | if (!mpath->is_gate && mesh_gate_num(sdata) > 0) { |
| 1181 | ret = mesh_path_send_to_gates(mpath); |
| 1182 | if (ret) |
| 1183 | mhwmp_dbg(sdata, "no gate was reachable\n"); |
| 1184 | } else |
| 1185 | mesh_path_flush_pending(mpath); |
| 1186 | } |
| 1187 | } |
| 1188 | |
| 1189 | void |
| 1190 | mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata) |
| 1191 | { |
| 1192 | struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; |
| 1193 | u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval; |
| 1194 | u8 flags, target_flags = 0; |
| 1195 | |
| 1196 | flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol) |
| 1197 | ? RANN_FLAG_IS_GATE : 0; |
| 1198 | |
| 1199 | switch (ifmsh->mshcfg.dot11MeshHWMPRootMode) { |
| 1200 | case IEEE80211_PROACTIVE_RANN: |
| 1201 | mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr, |
| 1202 | cpu_to_le32(++ifmsh->sn), |
| 1203 | 0, NULL, 0, broadcast_addr, |
| 1204 | 0, ifmsh->mshcfg.element_ttl, |
| 1205 | cpu_to_le32(interval), 0, 0, sdata); |
| 1206 | break; |
| 1207 | case IEEE80211_PROACTIVE_PREQ_WITH_PREP: |
| 1208 | flags |= IEEE80211_PREQ_PROACTIVE_PREP_FLAG; |
| 1209 | case IEEE80211_PROACTIVE_PREQ_NO_PREP: |
| 1210 | interval = ifmsh->mshcfg.dot11MeshHWMPactivePathToRootTimeout; |
| 1211 | target_flags |= IEEE80211_PREQ_TO_FLAG | |
| 1212 | IEEE80211_PREQ_USN_FLAG; |
| 1213 | mesh_path_sel_frame_tx(MPATH_PREQ, flags, sdata->vif.addr, |
| 1214 | cpu_to_le32(++ifmsh->sn), target_flags, |
| 1215 | (u8 *) broadcast_addr, 0, broadcast_addr, |
| 1216 | 0, ifmsh->mshcfg.element_ttl, |
| 1217 | cpu_to_le32(interval), |
| 1218 | 0, cpu_to_le32(ifmsh->preq_id++), sdata); |
| 1219 | break; |
| 1220 | default: |
| 1221 | mhwmp_dbg(sdata, "Proactive mechanism not supported\n"); |
| 1222 | return; |
| 1223 | } |
| 1224 | } |