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050ac52c LCC |
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 | ||
10 | #include "mesh.h" | |
11 | ||
050ac52c LCC |
12 | #define TEST_FRAME_LEN 8192 |
13 | #define MAX_METRIC 0xffffffff | |
14 | #define ARITH_SHIFT 8 | |
15 | ||
16 | /* Number of frames buffered per destination for unresolved destinations */ | |
17 | #define MESH_FRAME_QUEUE_LEN 10 | |
18 | #define MAX_PREQ_QUEUE_LEN 64 | |
19 | ||
20 | /* Destination only */ | |
21 | #define MP_F_DO 0x1 | |
22 | /* Reply and forward */ | |
23 | #define MP_F_RF 0x2 | |
24 | ||
a00de5d0 LCC |
25 | static inline u32 u32_field_get(u8 *preq_elem, int offset, bool ae) |
26 | { | |
27 | if (ae) | |
28 | offset += 6; | |
ae7245cb | 29 | return get_unaligned_le32(preq_elem + offset); |
a00de5d0 LCC |
30 | } |
31 | ||
050ac52c | 32 | /* HWMP IE processing macros */ |
a00de5d0 LCC |
33 | #define AE_F (1<<6) |
34 | #define AE_F_SET(x) (*x & AE_F) | |
35 | #define PREQ_IE_FLAGS(x) (*(x)) | |
36 | #define PREQ_IE_HOPCOUNT(x) (*(x + 1)) | |
37 | #define PREQ_IE_TTL(x) (*(x + 2)) | |
38 | #define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0) | |
39 | #define PREQ_IE_ORIG_ADDR(x) (x + 7) | |
40 | #define PREQ_IE_ORIG_DSN(x) u32_field_get(x, 13, 0); | |
41 | #define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x)); | |
42 | #define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x)); | |
43 | #define PREQ_IE_DST_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26)) | |
44 | #define PREQ_IE_DST_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27) | |
45 | #define PREQ_IE_DST_DSN(x) u32_field_get(x, 33, AE_F_SET(x)); | |
46 | ||
47 | ||
48 | #define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x) | |
49 | #define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x) | |
50 | #define PREP_IE_TTL(x) PREQ_IE_TTL(x) | |
51 | #define PREP_IE_ORIG_ADDR(x) (x + 3) | |
52 | #define PREP_IE_ORIG_DSN(x) u32_field_get(x, 9, 0); | |
53 | #define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x)); | |
54 | #define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x)); | |
55 | #define PREP_IE_DST_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21) | |
56 | #define PREP_IE_DST_DSN(x) u32_field_get(x, 27, AE_F_SET(x)); | |
57 | ||
58 | #define PERR_IE_DST_ADDR(x) (x + 2) | |
59 | #define PERR_IE_DST_DSN(x) u32_field_get(x, 8, 0); | |
050ac52c LCC |
60 | |
61 | #define TU_TO_EXP_TIME(x) (jiffies + msecs_to_jiffies(x * 1024 / 1000)) | |
62 | #define MSEC_TO_TU(x) (x*1000/1024) | |
63 | #define DSN_GT(x, y) ((long) (y) - (long) (x) < 0) | |
64 | #define DSN_LT(x, y) ((long) (x) - (long) (y) < 0) | |
65 | ||
66 | #define net_traversal_jiffies(s) \ | |
67 | msecs_to_jiffies(s->u.sta.mshcfg.dot11MeshHWMPnetDiameterTraversalTime) | |
68 | #define default_lifetime(s) \ | |
69 | MSEC_TO_TU(s->u.sta.mshcfg.dot11MeshHWMPactivePathTimeout) | |
70 | #define min_preq_int_jiff(s) \ | |
71 | (msecs_to_jiffies(s->u.sta.mshcfg.dot11MeshHWMPpreqMinInterval)) | |
72 | #define max_preq_retries(s) (s->u.sta.mshcfg.dot11MeshHWMPmaxPREQretries) | |
73 | #define disc_timeout_jiff(s) \ | |
74 | msecs_to_jiffies(sdata->u.sta.mshcfg.min_discovery_timeout) | |
75 | ||
76 | enum mpath_frame_type { | |
77 | MPATH_PREQ = 0, | |
78 | MPATH_PREP, | |
79 | MPATH_PERR | |
80 | }; | |
81 | ||
82 | static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags, | |
83 | u8 *orig_addr, __le32 orig_dsn, u8 dst_flags, u8 *dst, | |
84 | __le32 dst_dsn, u8 *da, u8 hop_count, u8 ttl, __le32 lifetime, | |
85 | __le32 metric, __le32 preq_id, struct net_device *dev) | |
86 | { | |
87 | struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); | |
88 | struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400); | |
89 | struct ieee80211_mgmt *mgmt; | |
90 | u8 *pos; | |
91 | int ie_len; | |
92 | ||
93 | if (!skb) | |
94 | return -1; | |
95 | skb_reserve(skb, local->hw.extra_tx_headroom); | |
96 | /* 25 is the size of the common mgmt part (24) plus the size of the | |
97 | * common action part (1) | |
98 | */ | |
99 | mgmt = (struct ieee80211_mgmt *) | |
100 | skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action)); | |
101 | memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action)); | |
102 | mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT, | |
103 | IEEE80211_STYPE_ACTION); | |
104 | ||
105 | memcpy(mgmt->da, da, ETH_ALEN); | |
106 | memcpy(mgmt->sa, dev->dev_addr, ETH_ALEN); | |
107 | /* BSSID is left zeroed, wildcard value */ | |
108 | mgmt->u.action.category = MESH_PATH_SEL_CATEGORY; | |
109 | mgmt->u.action.u.mesh_action.action_code = action; | |
110 | ||
111 | switch (action) { | |
112 | case MPATH_PREQ: | |
113 | ie_len = 37; | |
114 | pos = skb_put(skb, 2 + ie_len); | |
115 | *pos++ = WLAN_EID_PREQ; | |
116 | break; | |
117 | case MPATH_PREP: | |
118 | ie_len = 31; | |
119 | pos = skb_put(skb, 2 + ie_len); | |
120 | *pos++ = WLAN_EID_PREP; | |
121 | break; | |
122 | default: | |
812714d7 | 123 | kfree_skb(skb); |
050ac52c LCC |
124 | return -ENOTSUPP; |
125 | break; | |
126 | } | |
127 | *pos++ = ie_len; | |
128 | *pos++ = flags; | |
129 | *pos++ = hop_count; | |
130 | *pos++ = ttl; | |
131 | if (action == MPATH_PREQ) { | |
132 | memcpy(pos, &preq_id, 4); | |
133 | pos += 4; | |
134 | } | |
135 | memcpy(pos, orig_addr, ETH_ALEN); | |
136 | pos += ETH_ALEN; | |
137 | memcpy(pos, &orig_dsn, 4); | |
138 | pos += 4; | |
139 | memcpy(pos, &lifetime, 4); | |
140 | pos += 4; | |
141 | memcpy(pos, &metric, 4); | |
142 | pos += 4; | |
143 | if (action == MPATH_PREQ) { | |
144 | /* destination count */ | |
145 | *pos++ = 1; | |
146 | *pos++ = dst_flags; | |
147 | } | |
148 | memcpy(pos, dst, ETH_ALEN); | |
149 | pos += ETH_ALEN; | |
150 | memcpy(pos, &dst_dsn, 4); | |
151 | ||
152 | ieee80211_sta_tx(dev, skb, 0); | |
153 | return 0; | |
154 | } | |
155 | ||
156 | /** | |
157 | * mesh_send_path error - Sends a PERR mesh management frame | |
158 | * | |
159 | * @dst: broken destination | |
160 | * @dst_dsn: dsn of the broken destination | |
161 | * @ra: node this frame is addressed to | |
162 | */ | |
163 | int mesh_path_error_tx(u8 *dst, __le32 dst_dsn, u8 *ra, | |
164 | struct net_device *dev) | |
165 | { | |
166 | struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); | |
167 | struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400); | |
168 | struct ieee80211_mgmt *mgmt; | |
169 | u8 *pos; | |
170 | int ie_len; | |
171 | ||
172 | if (!skb) | |
173 | return -1; | |
174 | skb_reserve(skb, local->hw.extra_tx_headroom); | |
175 | /* 25 is the size of the common mgmt part (24) plus the size of the | |
176 | * common action part (1) | |
177 | */ | |
178 | mgmt = (struct ieee80211_mgmt *) | |
179 | skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action)); | |
180 | memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action)); | |
181 | mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT, | |
182 | IEEE80211_STYPE_ACTION); | |
183 | ||
184 | memcpy(mgmt->da, ra, ETH_ALEN); | |
185 | memcpy(mgmt->sa, dev->dev_addr, ETH_ALEN); | |
186 | /* BSSID is left zeroed, wildcard value */ | |
187 | mgmt->u.action.category = MESH_PATH_SEL_CATEGORY; | |
188 | mgmt->u.action.u.mesh_action.action_code = MPATH_PERR; | |
189 | ie_len = 12; | |
190 | pos = skb_put(skb, 2 + ie_len); | |
191 | *pos++ = WLAN_EID_PERR; | |
192 | *pos++ = ie_len; | |
193 | /* mode flags, reserved */ | |
194 | *pos++ = 0; | |
195 | /* number of destinations */ | |
196 | *pos++ = 1; | |
197 | memcpy(pos, dst, ETH_ALEN); | |
198 | pos += ETH_ALEN; | |
199 | memcpy(pos, &dst_dsn, 4); | |
200 | ||
201 | ieee80211_sta_tx(dev, skb, 0); | |
202 | return 0; | |
203 | } | |
204 | ||
205 | static u32 airtime_link_metric_get(struct ieee80211_local *local, | |
206 | struct sta_info *sta) | |
207 | { | |
208 | struct ieee80211_supported_band *sband; | |
209 | /* This should be adjusted for each device */ | |
210 | int device_constant = 1 << ARITH_SHIFT; | |
211 | int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; | |
212 | int s_unit = 1 << ARITH_SHIFT; | |
213 | int rate, err; | |
214 | u32 tx_time, estimated_retx; | |
215 | u64 result; | |
216 | ||
217 | sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; | |
218 | ||
219 | if (sta->fail_avg >= 100) | |
220 | return MAX_METRIC; | |
221 | err = (sta->fail_avg << ARITH_SHIFT) / 100; | |
222 | ||
223 | /* bitrate is in units of 100 Kbps, while we need rate in units of | |
224 | * 1Mbps. This will be corrected on tx_time computation. | |
225 | */ | |
226 | rate = sband->bitrates[sta->txrate_idx].bitrate; | |
227 | tx_time = (device_constant + 10 * test_frame_len / rate); | |
228 | estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); | |
229 | result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ; | |
230 | return (u32)result; | |
231 | } | |
232 | ||
233 | /** | |
234 | * hwmp_route_info_get - Update routing info to originator and transmitter | |
235 | * | |
236 | * @dev: local mesh interface | |
237 | * @mgmt: mesh management frame | |
238 | * @hwmp_ie: hwmp information element (PREP or PREQ) | |
239 | * | |
240 | * This function updates the path routing information to the originator and the | |
241 | * transmitter of a HWMP PREQ or PREP fram. | |
242 | * | |
243 | * Returns: metric to frame originator or 0 if the frame should not be further | |
244 | * processed | |
245 | * | |
246 | * Notes: this function is the only place (besides user-provided info) where | |
247 | * path routing information is updated. | |
248 | */ | |
249 | static u32 hwmp_route_info_get(struct net_device *dev, | |
250 | struct ieee80211_mgmt *mgmt, | |
251 | u8 *hwmp_ie) | |
252 | { | |
253 | struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); | |
254 | struct mesh_path *mpath; | |
255 | struct sta_info *sta; | |
256 | bool fresh_info; | |
257 | u8 *orig_addr, *ta; | |
258 | u32 orig_dsn, orig_metric; | |
259 | unsigned long orig_lifetime, exp_time; | |
260 | u32 last_hop_metric, new_metric; | |
261 | bool process = true; | |
262 | u8 action = mgmt->u.action.u.mesh_action.action_code; | |
263 | ||
264 | rcu_read_lock(); | |
265 | sta = sta_info_get(local, mgmt->sa); | |
dc0b0f7d JB |
266 | if (!sta) { |
267 | rcu_read_unlock(); | |
050ac52c | 268 | return 0; |
dc0b0f7d | 269 | } |
050ac52c LCC |
270 | |
271 | last_hop_metric = airtime_link_metric_get(local, sta); | |
272 | /* Update and check originator routing info */ | |
273 | fresh_info = true; | |
274 | ||
275 | switch (action) { | |
276 | case MPATH_PREQ: | |
277 | orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); | |
278 | orig_dsn = PREQ_IE_ORIG_DSN(hwmp_ie); | |
279 | orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); | |
280 | orig_metric = PREQ_IE_METRIC(hwmp_ie); | |
281 | break; | |
282 | case MPATH_PREP: | |
283 | /* Originator here refers to the MP that was the destination in | |
284 | * the Path Request. The draft refers to that MP as the | |
285 | * destination address, even though usually it is the origin of | |
286 | * the PREP frame. We divert from the nomenclature in the draft | |
287 | * so that we can easily use a single function to gather path | |
288 | * information from both PREQ and PREP frames. | |
289 | */ | |
290 | orig_addr = PREP_IE_ORIG_ADDR(hwmp_ie); | |
291 | orig_dsn = PREP_IE_ORIG_DSN(hwmp_ie); | |
292 | orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); | |
293 | orig_metric = PREP_IE_METRIC(hwmp_ie); | |
294 | break; | |
295 | default: | |
dc0b0f7d | 296 | rcu_read_unlock(); |
050ac52c LCC |
297 | return 0; |
298 | } | |
299 | new_metric = orig_metric + last_hop_metric; | |
300 | if (new_metric < orig_metric) | |
301 | new_metric = MAX_METRIC; | |
302 | exp_time = TU_TO_EXP_TIME(orig_lifetime); | |
303 | ||
304 | if (memcmp(orig_addr, dev->dev_addr, ETH_ALEN) == 0) { | |
305 | /* This MP is the originator, we are not interested in this | |
306 | * frame, except for updating transmitter's path info. | |
307 | */ | |
308 | process = false; | |
309 | fresh_info = false; | |
310 | } else { | |
311 | mpath = mesh_path_lookup(orig_addr, dev); | |
312 | if (mpath) { | |
313 | spin_lock_bh(&mpath->state_lock); | |
314 | if (mpath->flags & MESH_PATH_FIXED) | |
315 | fresh_info = false; | |
316 | else if ((mpath->flags & MESH_PATH_ACTIVE) && | |
317 | (mpath->flags & MESH_PATH_DSN_VALID)) { | |
318 | if (DSN_GT(mpath->dsn, orig_dsn) || | |
319 | (mpath->dsn == orig_dsn && | |
320 | action == MPATH_PREQ && | |
321 | new_metric > mpath->metric)) { | |
322 | process = false; | |
323 | fresh_info = false; | |
324 | } | |
325 | } | |
326 | } else { | |
327 | mesh_path_add(orig_addr, dev); | |
328 | mpath = mesh_path_lookup(orig_addr, dev); | |
329 | if (!mpath) { | |
330 | rcu_read_unlock(); | |
050ac52c LCC |
331 | return 0; |
332 | } | |
333 | spin_lock_bh(&mpath->state_lock); | |
334 | } | |
335 | ||
336 | if (fresh_info) { | |
337 | mesh_path_assign_nexthop(mpath, sta); | |
338 | mpath->flags |= MESH_PATH_DSN_VALID; | |
339 | mpath->metric = new_metric; | |
340 | mpath->dsn = orig_dsn; | |
341 | mpath->exp_time = time_after(mpath->exp_time, exp_time) | |
342 | ? mpath->exp_time : exp_time; | |
343 | mesh_path_activate(mpath); | |
344 | spin_unlock_bh(&mpath->state_lock); | |
345 | mesh_path_tx_pending(mpath); | |
346 | /* draft says preq_id should be saved to, but there does | |
347 | * not seem to be any use for it, skipping by now | |
348 | */ | |
349 | } else | |
350 | spin_unlock_bh(&mpath->state_lock); | |
351 | } | |
352 | ||
353 | /* Update and check transmitter routing info */ | |
354 | ta = mgmt->sa; | |
355 | if (memcmp(orig_addr, ta, ETH_ALEN) == 0) | |
356 | fresh_info = false; | |
357 | else { | |
358 | fresh_info = true; | |
359 | ||
360 | mpath = mesh_path_lookup(ta, dev); | |
361 | if (mpath) { | |
362 | spin_lock_bh(&mpath->state_lock); | |
363 | if ((mpath->flags & MESH_PATH_FIXED) || | |
364 | ((mpath->flags & MESH_PATH_ACTIVE) && | |
365 | (last_hop_metric > mpath->metric))) | |
366 | fresh_info = false; | |
367 | } else { | |
368 | mesh_path_add(ta, dev); | |
369 | mpath = mesh_path_lookup(ta, dev); | |
370 | if (!mpath) { | |
371 | rcu_read_unlock(); | |
050ac52c LCC |
372 | return 0; |
373 | } | |
374 | spin_lock_bh(&mpath->state_lock); | |
375 | } | |
376 | ||
377 | if (fresh_info) { | |
378 | mesh_path_assign_nexthop(mpath, sta); | |
379 | mpath->flags &= ~MESH_PATH_DSN_VALID; | |
380 | mpath->metric = last_hop_metric; | |
381 | mpath->exp_time = time_after(mpath->exp_time, exp_time) | |
382 | ? mpath->exp_time : exp_time; | |
383 | mesh_path_activate(mpath); | |
384 | spin_unlock_bh(&mpath->state_lock); | |
385 | mesh_path_tx_pending(mpath); | |
386 | } else | |
387 | spin_unlock_bh(&mpath->state_lock); | |
388 | } | |
389 | ||
050ac52c LCC |
390 | rcu_read_unlock(); |
391 | ||
392 | return process ? new_metric : 0; | |
393 | } | |
394 | ||
395 | static void hwmp_preq_frame_process(struct net_device *dev, | |
396 | struct ieee80211_mgmt *mgmt, | |
397 | u8 *preq_elem, u32 metric) { | |
398 | struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); | |
399 | struct ieee80211_if_sta *ifsta = &sdata->u.sta; | |
400 | struct mesh_path *mpath; | |
401 | u8 *dst_addr, *orig_addr; | |
402 | u8 dst_flags, ttl; | |
403 | u32 orig_dsn, dst_dsn, lifetime; | |
404 | bool reply = false; | |
405 | bool forward = true; | |
406 | ||
407 | /* Update destination DSN, if present */ | |
408 | dst_addr = PREQ_IE_DST_ADDR(preq_elem); | |
409 | orig_addr = PREQ_IE_ORIG_ADDR(preq_elem); | |
410 | dst_dsn = PREQ_IE_DST_DSN(preq_elem); | |
411 | orig_dsn = PREQ_IE_ORIG_DSN(preq_elem); | |
412 | dst_flags = PREQ_IE_DST_F(preq_elem); | |
413 | ||
414 | if (memcmp(dst_addr, dev->dev_addr, ETH_ALEN) == 0) { | |
415 | forward = false; | |
416 | reply = true; | |
417 | metric = 0; | |
418 | if (time_after(jiffies, ifsta->last_dsn_update + | |
419 | net_traversal_jiffies(sdata)) || | |
420 | time_before(jiffies, ifsta->last_dsn_update)) { | |
421 | dst_dsn = ++ifsta->dsn; | |
422 | ifsta->last_dsn_update = jiffies; | |
423 | } | |
424 | } else { | |
425 | rcu_read_lock(); | |
426 | mpath = mesh_path_lookup(dst_addr, dev); | |
427 | if (mpath) { | |
428 | if ((!(mpath->flags & MESH_PATH_DSN_VALID)) || | |
429 | DSN_LT(mpath->dsn, dst_dsn)) { | |
430 | mpath->dsn = dst_dsn; | |
431 | mpath->flags &= MESH_PATH_DSN_VALID; | |
432 | } else if ((!(dst_flags & MP_F_DO)) && | |
433 | (mpath->flags & MESH_PATH_ACTIVE)) { | |
434 | reply = true; | |
435 | metric = mpath->metric; | |
436 | dst_dsn = mpath->dsn; | |
437 | if (dst_flags & MP_F_RF) | |
438 | dst_flags |= MP_F_DO; | |
439 | else | |
440 | forward = false; | |
441 | } | |
442 | } | |
443 | rcu_read_unlock(); | |
444 | } | |
445 | ||
446 | if (reply) { | |
447 | lifetime = PREQ_IE_LIFETIME(preq_elem); | |
448 | ttl = ifsta->mshcfg.dot11MeshTTL; | |
449 | if (ttl != 0) | |
450 | mesh_path_sel_frame_tx(MPATH_PREP, 0, dst_addr, | |
aa2b5928 LCC |
451 | cpu_to_le32(dst_dsn), 0, orig_addr, |
452 | cpu_to_le32(orig_dsn), mgmt->sa, 0, ttl, | |
453 | cpu_to_le32(lifetime), cpu_to_le32(metric), | |
050ac52c LCC |
454 | 0, dev); |
455 | else | |
456 | ifsta->mshstats.dropped_frames_ttl++; | |
457 | } | |
458 | ||
459 | if (forward) { | |
460 | u32 preq_id; | |
461 | u8 hopcount, flags; | |
462 | ||
463 | ttl = PREQ_IE_TTL(preq_elem); | |
464 | lifetime = PREQ_IE_LIFETIME(preq_elem); | |
465 | if (ttl <= 1) { | |
466 | ifsta->mshstats.dropped_frames_ttl++; | |
467 | return; | |
468 | } | |
469 | --ttl; | |
470 | flags = PREQ_IE_FLAGS(preq_elem); | |
471 | preq_id = PREQ_IE_PREQ_ID(preq_elem); | |
472 | hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1; | |
473 | mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr, | |
aa2b5928 LCC |
474 | cpu_to_le32(orig_dsn), dst_flags, dst_addr, |
475 | cpu_to_le32(dst_dsn), dev->broadcast, | |
476 | hopcount, ttl, cpu_to_le32(lifetime), | |
477 | cpu_to_le32(metric), cpu_to_le32(preq_id), | |
050ac52c LCC |
478 | dev); |
479 | ifsta->mshstats.fwded_frames++; | |
480 | } | |
481 | } | |
482 | ||
483 | ||
484 | static void hwmp_prep_frame_process(struct net_device *dev, | |
485 | struct ieee80211_mgmt *mgmt, | |
486 | u8 *prep_elem, u32 metric) | |
487 | { | |
488 | struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); | |
489 | struct mesh_path *mpath; | |
490 | u8 *dst_addr, *orig_addr; | |
491 | u8 ttl, hopcount, flags; | |
492 | u8 next_hop[ETH_ALEN]; | |
493 | u32 dst_dsn, orig_dsn, lifetime; | |
494 | ||
495 | /* Note that we divert from the draft nomenclature and denominate | |
496 | * destination to what the draft refers to as origininator. So in this | |
497 | * function destnation refers to the final destination of the PREP, | |
498 | * which corresponds with the originator of the PREQ which this PREP | |
499 | * replies | |
500 | */ | |
501 | dst_addr = PREP_IE_DST_ADDR(prep_elem); | |
502 | if (memcmp(dst_addr, dev->dev_addr, ETH_ALEN) == 0) | |
503 | /* destination, no forwarding required */ | |
504 | return; | |
505 | ||
506 | ttl = PREP_IE_TTL(prep_elem); | |
507 | if (ttl <= 1) { | |
508 | sdata->u.sta.mshstats.dropped_frames_ttl++; | |
509 | return; | |
510 | } | |
511 | ||
512 | rcu_read_lock(); | |
513 | mpath = mesh_path_lookup(dst_addr, dev); | |
514 | if (mpath) | |
515 | spin_lock_bh(&mpath->state_lock); | |
516 | else | |
517 | goto fail; | |
518 | if (!(mpath->flags & MESH_PATH_ACTIVE)) { | |
519 | spin_unlock_bh(&mpath->state_lock); | |
520 | goto fail; | |
521 | } | |
522 | memcpy(next_hop, mpath->next_hop->addr, ETH_ALEN); | |
523 | spin_unlock_bh(&mpath->state_lock); | |
524 | --ttl; | |
525 | flags = PREP_IE_FLAGS(prep_elem); | |
526 | lifetime = PREP_IE_LIFETIME(prep_elem); | |
527 | hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1; | |
528 | orig_addr = PREP_IE_ORIG_ADDR(prep_elem); | |
529 | dst_dsn = PREP_IE_DST_DSN(prep_elem); | |
530 | orig_dsn = PREP_IE_ORIG_DSN(prep_elem); | |
531 | ||
532 | mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr, | |
aa2b5928 LCC |
533 | cpu_to_le32(orig_dsn), 0, dst_addr, |
534 | cpu_to_le32(dst_dsn), mpath->next_hop->addr, hopcount, ttl, | |
535 | cpu_to_le32(lifetime), cpu_to_le32(metric), | |
050ac52c LCC |
536 | 0, dev); |
537 | rcu_read_unlock(); | |
538 | sdata->u.sta.mshstats.fwded_frames++; | |
539 | return; | |
540 | ||
541 | fail: | |
542 | rcu_read_unlock(); | |
543 | sdata->u.sta.mshstats.dropped_frames_no_route++; | |
544 | return; | |
545 | } | |
546 | ||
547 | static void hwmp_perr_frame_process(struct net_device *dev, | |
548 | struct ieee80211_mgmt *mgmt, u8 *perr_elem) | |
549 | { | |
550 | struct mesh_path *mpath; | |
551 | u8 *ta, *dst_addr; | |
552 | u32 dst_dsn; | |
553 | ||
554 | ta = mgmt->sa; | |
555 | dst_addr = PERR_IE_DST_ADDR(perr_elem); | |
556 | dst_dsn = PERR_IE_DST_DSN(perr_elem); | |
557 | rcu_read_lock(); | |
558 | mpath = mesh_path_lookup(dst_addr, dev); | |
559 | if (mpath) { | |
560 | spin_lock_bh(&mpath->state_lock); | |
561 | if (mpath->flags & MESH_PATH_ACTIVE && | |
562 | memcmp(ta, mpath->next_hop->addr, ETH_ALEN) == 0 && | |
563 | (!(mpath->flags & MESH_PATH_DSN_VALID) || | |
564 | DSN_GT(dst_dsn, mpath->dsn))) { | |
565 | mpath->flags &= ~MESH_PATH_ACTIVE; | |
566 | mpath->dsn = dst_dsn; | |
567 | spin_unlock_bh(&mpath->state_lock); | |
aa2b5928 | 568 | mesh_path_error_tx(dst_addr, cpu_to_le32(dst_dsn), |
37659ff8 | 569 | dev->broadcast, dev); |
050ac52c LCC |
570 | } else |
571 | spin_unlock_bh(&mpath->state_lock); | |
572 | } | |
573 | rcu_read_unlock(); | |
574 | } | |
575 | ||
576 | ||
577 | ||
578 | void mesh_rx_path_sel_frame(struct net_device *dev, | |
579 | struct ieee80211_mgmt *mgmt, | |
580 | size_t len) | |
581 | { | |
582 | struct ieee802_11_elems elems; | |
583 | size_t baselen; | |
584 | u32 last_hop_metric; | |
585 | ||
586 | baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt; | |
587 | ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable, | |
588 | len - baselen, &elems); | |
589 | ||
590 | switch (mgmt->u.action.u.mesh_action.action_code) { | |
591 | case MPATH_PREQ: | |
592 | if (!elems.preq || elems.preq_len != 37) | |
593 | /* Right now we support just 1 destination and no AE */ | |
594 | return; | |
595 | last_hop_metric = hwmp_route_info_get(dev, mgmt, elems.preq); | |
596 | if (!last_hop_metric) | |
597 | return; | |
598 | hwmp_preq_frame_process(dev, mgmt, elems.preq, last_hop_metric); | |
599 | break; | |
600 | case MPATH_PREP: | |
601 | if (!elems.prep || elems.prep_len != 31) | |
602 | /* Right now we support no AE */ | |
603 | return; | |
604 | last_hop_metric = hwmp_route_info_get(dev, mgmt, elems.prep); | |
605 | if (!last_hop_metric) | |
606 | return; | |
607 | hwmp_prep_frame_process(dev, mgmt, elems.prep, last_hop_metric); | |
608 | break; | |
609 | case MPATH_PERR: | |
610 | if (!elems.perr || elems.perr_len != 12) | |
611 | /* Right now we support only one destination per PERR */ | |
612 | return; | |
613 | hwmp_perr_frame_process(dev, mgmt, elems.perr); | |
614 | default: | |
615 | return; | |
616 | } | |
617 | ||
618 | } | |
619 | ||
620 | /** | |
621 | * mesh_queue_preq - queue a PREQ to a given destination | |
622 | * | |
623 | * @mpath: mesh path to discover | |
624 | * @flags: special attributes of the PREQ to be sent | |
625 | * | |
626 | * Locking: the function must be called from within a rcu read lock block. | |
627 | * | |
628 | */ | |
629 | static void mesh_queue_preq(struct mesh_path *mpath, u8 flags) | |
630 | { | |
631 | struct ieee80211_sub_if_data *sdata = | |
632 | IEEE80211_DEV_TO_SUB_IF(mpath->dev); | |
633 | struct ieee80211_if_sta *ifsta = &sdata->u.sta; | |
634 | struct mesh_preq_queue *preq_node; | |
635 | ||
636 | preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_KERNEL); | |
637 | if (!preq_node) { | |
638 | printk(KERN_DEBUG "Mesh HWMP: could not allocate PREQ node\n"); | |
639 | return; | |
640 | } | |
641 | ||
642 | spin_lock(&ifsta->mesh_preq_queue_lock); | |
643 | if (ifsta->preq_queue_len == MAX_PREQ_QUEUE_LEN) { | |
644 | spin_unlock(&ifsta->mesh_preq_queue_lock); | |
645 | kfree(preq_node); | |
646 | if (printk_ratelimit()) | |
647 | printk(KERN_DEBUG "Mesh HWMP: PREQ node queue full\n"); | |
648 | return; | |
649 | } | |
650 | ||
651 | memcpy(preq_node->dst, mpath->dst, ETH_ALEN); | |
652 | preq_node->flags = flags; | |
653 | ||
654 | list_add_tail(&preq_node->list, &ifsta->preq_queue.list); | |
655 | ++ifsta->preq_queue_len; | |
656 | spin_unlock(&ifsta->mesh_preq_queue_lock); | |
657 | ||
658 | if (time_after(jiffies, ifsta->last_preq + min_preq_int_jiff(sdata))) | |
659 | queue_work(sdata->local->hw.workqueue, &ifsta->work); | |
660 | ||
661 | else if (time_before(jiffies, ifsta->last_preq)) { | |
662 | /* avoid long wait if did not send preqs for a long time | |
663 | * and jiffies wrapped around | |
664 | */ | |
665 | ifsta->last_preq = jiffies - min_preq_int_jiff(sdata) - 1; | |
666 | queue_work(sdata->local->hw.workqueue, &ifsta->work); | |
667 | } else | |
668 | mod_timer(&ifsta->mesh_path_timer, ifsta->last_preq + | |
669 | min_preq_int_jiff(sdata)); | |
670 | } | |
671 | ||
672 | /** | |
673 | * mesh_path_start_discovery - launch a path discovery from the PREQ queue | |
674 | * | |
675 | * @dev: local mesh interface | |
676 | */ | |
677 | void mesh_path_start_discovery(struct net_device *dev) | |
678 | { | |
679 | struct ieee80211_sub_if_data *sdata = | |
680 | IEEE80211_DEV_TO_SUB_IF(dev); | |
681 | struct ieee80211_if_sta *ifsta = &sdata->u.sta; | |
682 | struct mesh_preq_queue *preq_node; | |
683 | struct mesh_path *mpath; | |
684 | u8 ttl, dst_flags; | |
685 | u32 lifetime; | |
686 | ||
687 | spin_lock(&ifsta->mesh_preq_queue_lock); | |
688 | if (!ifsta->preq_queue_len || | |
689 | time_before(jiffies, ifsta->last_preq + | |
690 | min_preq_int_jiff(sdata))) { | |
691 | spin_unlock(&ifsta->mesh_preq_queue_lock); | |
692 | return; | |
693 | } | |
694 | ||
695 | preq_node = list_first_entry(&ifsta->preq_queue.list, | |
696 | struct mesh_preq_queue, list); | |
697 | list_del(&preq_node->list); | |
698 | --ifsta->preq_queue_len; | |
699 | spin_unlock(&ifsta->mesh_preq_queue_lock); | |
700 | ||
701 | rcu_read_lock(); | |
702 | mpath = mesh_path_lookup(preq_node->dst, dev); | |
703 | if (!mpath) | |
704 | goto enddiscovery; | |
705 | ||
706 | spin_lock_bh(&mpath->state_lock); | |
707 | if (preq_node->flags & PREQ_Q_F_START) { | |
708 | if (mpath->flags & MESH_PATH_RESOLVING) { | |
709 | spin_unlock_bh(&mpath->state_lock); | |
710 | goto enddiscovery; | |
711 | } else { | |
712 | mpath->flags &= ~MESH_PATH_RESOLVED; | |
713 | mpath->flags |= MESH_PATH_RESOLVING; | |
714 | mpath->discovery_retries = 0; | |
715 | mpath->discovery_timeout = disc_timeout_jiff(sdata); | |
716 | } | |
717 | } else if (!(mpath->flags & MESH_PATH_RESOLVING) || | |
718 | mpath->flags & MESH_PATH_RESOLVED) { | |
719 | mpath->flags &= ~MESH_PATH_RESOLVING; | |
720 | spin_unlock_bh(&mpath->state_lock); | |
721 | goto enddiscovery; | |
722 | } | |
723 | ||
724 | ifsta->last_preq = jiffies; | |
725 | ||
726 | if (time_after(jiffies, ifsta->last_dsn_update + | |
727 | net_traversal_jiffies(sdata)) || | |
728 | time_before(jiffies, ifsta->last_dsn_update)) { | |
729 | ++ifsta->dsn; | |
730 | sdata->u.sta.last_dsn_update = jiffies; | |
731 | } | |
732 | lifetime = default_lifetime(sdata); | |
733 | ttl = sdata->u.sta.mshcfg.dot11MeshTTL; | |
734 | if (ttl == 0) { | |
735 | sdata->u.sta.mshstats.dropped_frames_ttl++; | |
736 | spin_unlock_bh(&mpath->state_lock); | |
737 | goto enddiscovery; | |
738 | } | |
739 | ||
740 | if (preq_node->flags & PREQ_Q_F_REFRESH) | |
741 | dst_flags = MP_F_DO; | |
742 | else | |
743 | dst_flags = MP_F_RF; | |
744 | ||
745 | spin_unlock_bh(&mpath->state_lock); | |
746 | mesh_path_sel_frame_tx(MPATH_PREQ, 0, dev->dev_addr, | |
aa2b5928 LCC |
747 | cpu_to_le32(ifsta->dsn), dst_flags, mpath->dst, |
748 | cpu_to_le32(mpath->dsn), dev->broadcast, 0, | |
749 | ttl, cpu_to_le32(lifetime), 0, | |
750 | cpu_to_le32(ifsta->preq_id++), dev); | |
050ac52c LCC |
751 | mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout); |
752 | ||
753 | enddiscovery: | |
754 | rcu_read_unlock(); | |
755 | kfree(preq_node); | |
756 | } | |
757 | ||
758 | /** | |
759 | * ieee80211s_lookup_nexthop - put the appropriate next hop on a mesh frame | |
760 | * | |
761 | * @next_hop: output argument for next hop address | |
762 | * @skb: frame to be sent | |
763 | * @dev: network device the frame will be sent through | |
764 | * | |
765 | * Returns: 0 if the next hop was found. Nonzero otherwise. If no next hop is | |
766 | * found, the function will start a path discovery and queue the frame so it is | |
767 | * sent when the path is resolved. This means the caller must not free the skb | |
768 | * in this case. | |
769 | */ | |
770 | int mesh_nexthop_lookup(u8 *next_hop, struct sk_buff *skb, | |
771 | struct net_device *dev) | |
772 | { | |
773 | struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); | |
774 | struct sk_buff *skb_to_free = NULL; | |
775 | struct mesh_path *mpath; | |
776 | int err = 0; | |
777 | ||
778 | rcu_read_lock(); | |
779 | mpath = mesh_path_lookup(skb->data, dev); | |
780 | ||
781 | if (!mpath) { | |
782 | mesh_path_add(skb->data, dev); | |
783 | mpath = mesh_path_lookup(skb->data, dev); | |
784 | if (!mpath) { | |
785 | dev_kfree_skb(skb); | |
786 | sdata->u.sta.mshstats.dropped_frames_no_route++; | |
787 | err = -ENOSPC; | |
788 | goto endlookup; | |
789 | } | |
790 | } | |
791 | ||
792 | if (mpath->flags & MESH_PATH_ACTIVE) { | |
793 | if (time_after(jiffies, mpath->exp_time - | |
794 | msecs_to_jiffies(sdata->u.sta.mshcfg.path_refresh_time)) | |
795 | && skb->pkt_type != PACKET_OTHERHOST | |
796 | && !(mpath->flags & MESH_PATH_RESOLVING) | |
797 | && !(mpath->flags & MESH_PATH_FIXED)) { | |
798 | mesh_queue_preq(mpath, | |
799 | PREQ_Q_F_START | PREQ_Q_F_REFRESH); | |
800 | } | |
801 | memcpy(next_hop, mpath->next_hop->addr, | |
802 | ETH_ALEN); | |
803 | } else { | |
804 | if (!(mpath->flags & MESH_PATH_RESOLVING)) { | |
805 | /* Start discovery only if it is not running yet */ | |
806 | mesh_queue_preq(mpath, PREQ_Q_F_START); | |
807 | } | |
808 | ||
809 | if (skb_queue_len(&mpath->frame_queue) >= | |
810 | MESH_FRAME_QUEUE_LEN) { | |
811 | skb_to_free = mpath->frame_queue.next; | |
812 | skb_unlink(skb_to_free, &mpath->frame_queue); | |
813 | } | |
814 | ||
815 | skb_queue_tail(&mpath->frame_queue, skb); | |
816 | if (skb_to_free) | |
817 | mesh_path_discard_frame(skb_to_free, dev); | |
818 | err = -ENOENT; | |
819 | } | |
820 | ||
821 | endlookup: | |
822 | rcu_read_unlock(); | |
823 | return err; | |
824 | } | |
825 | ||
826 | void mesh_path_timer(unsigned long data) | |
827 | { | |
828 | struct ieee80211_sub_if_data *sdata; | |
829 | struct mesh_path *mpath; | |
050ac52c LCC |
830 | |
831 | rcu_read_lock(); | |
832 | mpath = (struct mesh_path *) data; | |
833 | mpath = rcu_dereference(mpath); | |
834 | if (!mpath) | |
835 | goto endmpathtimer; | |
836 | spin_lock_bh(&mpath->state_lock); | |
837 | sdata = IEEE80211_DEV_TO_SUB_IF(mpath->dev); | |
cfa22c71 | 838 | if (mpath->flags & MESH_PATH_RESOLVED || |
050ac52c LCC |
839 | (!(mpath->flags & MESH_PATH_RESOLVING))) |
840 | mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED); | |
841 | else if (mpath->discovery_retries < max_preq_retries(sdata)) { | |
842 | ++mpath->discovery_retries; | |
843 | mpath->discovery_timeout *= 2; | |
844 | mesh_queue_preq(mpath, 0); | |
845 | } else { | |
846 | mpath->flags = 0; | |
847 | mpath->exp_time = jiffies; | |
848 | mesh_path_flush_pending(mpath); | |
849 | } | |
850 | ||
851 | spin_unlock_bh(&mpath->state_lock); | |
852 | endmpathtimer: | |
853 | rcu_read_unlock(); | |
050ac52c | 854 | } |