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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2007-2012 Siemens AG
4 *
5 * Written by:
6 * Pavel Smolenskiy <[email protected]>
7 * Maxim Gorbachyov <[email protected]>
8 * Dmitry Eremin-Solenikov <[email protected]>
9 * Alexander Smirnov <[email protected]>
10 */
11
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/netdevice.h>
15#include <linux/crc-ccitt.h>
16#include <linux/unaligned.h>
17
18#include <net/mac802154.h>
19#include <net/ieee802154_netdev.h>
20#include <net/nl802154.h>
21
22#include "ieee802154_i.h"
23
24static int ieee802154_deliver_skb(struct sk_buff *skb)
25{
26 skb->ip_summed = CHECKSUM_UNNECESSARY;
27 skb->protocol = htons(ETH_P_IEEE802154);
28
29 return netif_receive_skb(skb);
30}
31
32void mac802154_rx_beacon_worker(struct work_struct *work)
33{
34 struct ieee802154_local *local =
35 container_of(work, struct ieee802154_local, rx_beacon_work);
36 struct cfg802154_mac_pkt *mac_pkt;
37
38 for (;;) {
39 spin_lock_bh(&local->rx_lock);
40 mac_pkt = list_first_entry_or_null(&local->rx_beacon_list,
41 struct cfg802154_mac_pkt, node);
42 if (mac_pkt)
43 list_del(&mac_pkt->node);
44 spin_unlock_bh(&local->rx_lock);
45 if (!mac_pkt)
46 break;
47
48 mac802154_process_beacon(local, mac_pkt->skb,
49 mac_pkt->page, mac_pkt->channel);
50
51 netdev_put(mac_pkt->sdata->dev, &mac_pkt->dev_tracker);
52 kfree_skb(mac_pkt->skb);
53 kfree(mac_pkt);
54 }
55}
56
57static bool mac802154_should_answer_beacon_req(struct ieee802154_local *local)
58{
59 struct cfg802154_beacon_request *beacon_req;
60 unsigned int interval;
61
62 rcu_read_lock();
63 beacon_req = rcu_dereference(local->beacon_req);
64 if (!beacon_req) {
65 rcu_read_unlock();
66 return false;
67 }
68
69 interval = beacon_req->interval;
70 rcu_read_unlock();
71
72 if (!mac802154_is_beaconing(local))
73 return false;
74
75 return interval == IEEE802154_ACTIVE_SCAN_DURATION;
76}
77
78static void mac802154_rx_mac_cmd(struct ieee802154_local *local,
79 struct cfg802154_mac_pkt *mac_pkt)
80{
81 u8 mac_cmd;
82 int rc;
83
84 rc = ieee802154_get_mac_cmd(mac_pkt->skb, &mac_cmd);
85 if (rc)
86 return;
87
88 switch (mac_cmd) {
89 case IEEE802154_CMD_BEACON_REQ:
90 dev_dbg(&mac_pkt->sdata->dev->dev, "processing BEACON REQ\n");
91 if (!mac802154_should_answer_beacon_req(local))
92 break;
93
94 queue_delayed_work(local->mac_wq, &local->beacon_work, 0);
95 break;
96
97 case IEEE802154_CMD_ASSOCIATION_RESP:
98 dev_dbg(&mac_pkt->sdata->dev->dev, "processing ASSOC RESP\n");
99 if (!mac802154_is_associating(local))
100 break;
101
102 mac802154_process_association_resp(mac_pkt->sdata, mac_pkt->skb);
103 break;
104
105 case IEEE802154_CMD_ASSOCIATION_REQ:
106 dev_dbg(&mac_pkt->sdata->dev->dev, "processing ASSOC REQ\n");
107 if (mac_pkt->sdata->wpan_dev.iftype != NL802154_IFTYPE_COORD)
108 break;
109
110 mac802154_process_association_req(mac_pkt->sdata, mac_pkt->skb);
111 break;
112
113 case IEEE802154_CMD_DISASSOCIATION_NOTIFY:
114 dev_dbg(&mac_pkt->sdata->dev->dev, "processing DISASSOC NOTIF\n");
115 if (mac_pkt->sdata->wpan_dev.iftype != NL802154_IFTYPE_COORD)
116 break;
117
118 mac802154_process_disassociation_notif(mac_pkt->sdata, mac_pkt->skb);
119 break;
120
121 default:
122 break;
123 }
124}
125
126void mac802154_rx_mac_cmd_worker(struct work_struct *work)
127{
128 struct ieee802154_local *local =
129 container_of(work, struct ieee802154_local, rx_mac_cmd_work);
130 struct cfg802154_mac_pkt *mac_pkt;
131
132 for (;;) {
133 spin_lock_bh(&local->rx_lock);
134 mac_pkt = list_first_entry_or_null(&local->rx_mac_cmd_list,
135 struct cfg802154_mac_pkt, node);
136 if (mac_pkt)
137 list_del(&mac_pkt->node);
138 spin_unlock_bh(&local->rx_lock);
139 if (!mac_pkt)
140 break;
141
142 /* A stopped interface cannot transmit; skipping avoids a
143 * needless association response (and the !netif_running()
144 * warning it would trip) during teardown. The beacon worker
145 * needs no such check as it never transmits.
146 */
147 if (ieee802154_sdata_running(mac_pkt->sdata))
148 mac802154_rx_mac_cmd(local, mac_pkt);
149
150 netdev_put(mac_pkt->sdata->dev, &mac_pkt->dev_tracker);
151 kfree_skb(mac_pkt->skb);
152 kfree(mac_pkt);
153 }
154}
155
156/**
157 * mac802154_flush_list - free queued RX frames on @list
158 * @list: rx_beacon_list or rx_mac_cmd_list
159 * @sdata: only free frames received on this interface, or %NULL for all
160 *
161 * Each frame pins the net_device it was received on (via netdev_hold()),
162 * so release that reference as the frame is dropped. Caller must hold
163 * local->rx_lock.
164 */
165void mac802154_flush_list(struct list_head *list,
166 struct ieee802154_sub_if_data *sdata)
167{
168 struct cfg802154_mac_pkt *mac_pkt, *tmp;
169
170 list_for_each_entry_safe(mac_pkt, tmp, list, node) {
171 if (sdata && mac_pkt->sdata != sdata)
172 continue;
173 list_del(&mac_pkt->node);
174 netdev_put(mac_pkt->sdata->dev, &mac_pkt->dev_tracker);
175 kfree_skb(mac_pkt->skb);
176 kfree(mac_pkt);
177 }
178}
179
180/**
181 * mac802154_flush_queued_pkts - drop queued RX work referencing @sdata
182 * @local: the mac802154 device
183 * @sdata: interface being removed
184 *
185 * The workers dereference the queued frame's interface directly
186 * (mac_pkt->sdata) or through skb->dev in mac802154_process_beacon(). Drop
187 * the not-yet-started entries belonging to @sdata before it is unregistered
188 * so their netdev reference is released; an entry already dequeued by a
189 * running worker keeps its own reference until the worker completes, which
190 * unregister_netdevice() then waits out.
191 */
192void mac802154_flush_queued_pkts(struct ieee802154_local *local,
193 struct ieee802154_sub_if_data *sdata)
194{
195 spin_lock_bh(&local->rx_lock);
196 mac802154_flush_list(&local->rx_beacon_list, sdata);
197 mac802154_flush_list(&local->rx_mac_cmd_list, sdata);
198 spin_unlock_bh(&local->rx_lock);
199}
200
201static int
202ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata,
203 struct sk_buff *skb, const struct ieee802154_hdr *hdr)
204{
205 struct wpan_phy *wpan_phy = sdata->local->hw.phy;
206 struct wpan_dev *wpan_dev = &sdata->wpan_dev;
207 struct cfg802154_mac_pkt *mac_pkt;
208 __le16 span, sshort;
209 int rc;
210
211 pr_debug("getting packet via slave interface %s\n", sdata->dev->name);
212
213 span = wpan_dev->pan_id;
214 sshort = wpan_dev->short_addr;
215
216 /* Level 3 filtering: Only beacons are accepted during scans */
217 if (sdata->required_filtering == IEEE802154_FILTERING_3_SCAN &&
218 sdata->required_filtering > wpan_phy->filtering) {
219 if (mac_cb(skb)->type != IEEE802154_FC_TYPE_BEACON) {
220 dev_dbg(&sdata->dev->dev,
221 "drop non-beacon frame (0x%x) during scan\n",
222 mac_cb(skb)->type);
223 goto fail;
224 }
225 }
226
227 switch (mac_cb(skb)->dest.mode) {
228 case IEEE802154_ADDR_NONE:
229 if (hdr->source.mode == IEEE802154_ADDR_NONE)
230 /* ACK comes with both addresses empty */
231 skb->pkt_type = PACKET_HOST;
232 else if (!wpan_dev->parent)
233 /* No dest means PAN coordinator is the recipient */
234 skb->pkt_type = PACKET_HOST;
235 else
236 /* We are not the PAN coordinator, just relaying */
237 skb->pkt_type = PACKET_OTHERHOST;
238 break;
239 case IEEE802154_ADDR_LONG:
240 if (mac_cb(skb)->dest.pan_id != span &&
241 mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST))
242 skb->pkt_type = PACKET_OTHERHOST;
243 else if (mac_cb(skb)->dest.extended_addr == wpan_dev->extended_addr)
244 skb->pkt_type = PACKET_HOST;
245 else
246 skb->pkt_type = PACKET_OTHERHOST;
247 break;
248 case IEEE802154_ADDR_SHORT:
249 if (mac_cb(skb)->dest.pan_id != span &&
250 mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST))
251 skb->pkt_type = PACKET_OTHERHOST;
252 else if (mac_cb(skb)->dest.short_addr == sshort)
253 skb->pkt_type = PACKET_HOST;
254 else if (mac_cb(skb)->dest.short_addr ==
255 cpu_to_le16(IEEE802154_ADDR_BROADCAST))
256 skb->pkt_type = PACKET_BROADCAST;
257 else
258 skb->pkt_type = PACKET_OTHERHOST;
259 break;
260 default:
261 pr_debug("invalid dest mode\n");
262 goto fail;
263 }
264
265 skb->dev = sdata->dev;
266
267 /* TODO this should be moved after netif_receive_skb call, otherwise
268 * wireshark will show a mac header with security fields and the
269 * payload is already decrypted.
270 */
271 rc = mac802154_llsec_decrypt(&sdata->sec, skb);
272 if (rc) {
273 pr_debug("decryption failed: %i\n", rc);
274 goto fail;
275 }
276
277 sdata->dev->stats.rx_packets++;
278 sdata->dev->stats.rx_bytes += skb->len;
279
280 switch (mac_cb(skb)->type) {
281 case IEEE802154_FC_TYPE_BEACON:
282 dev_dbg(&sdata->dev->dev, "BEACON received\n");
283 if (!mac802154_is_scanning(sdata->local))
284 goto fail;
285
286 mac_pkt = kzalloc_obj(*mac_pkt, GFP_ATOMIC);
287 if (!mac_pkt)
288 goto fail;
289
290 mac_pkt->skb = skb_get(skb);
291 mac_pkt->sdata = sdata;
292 mac_pkt->page = sdata->local->scan_page;
293 mac_pkt->channel = sdata->local->scan_channel;
294 netdev_hold(sdata->dev, &mac_pkt->dev_tracker, GFP_ATOMIC);
295 spin_lock(&sdata->local->rx_lock);
296 list_add_tail(&mac_pkt->node, &sdata->local->rx_beacon_list);
297 spin_unlock(&sdata->local->rx_lock);
298 queue_work(sdata->local->mac_wq, &sdata->local->rx_beacon_work);
299 return NET_RX_SUCCESS;
300
301 case IEEE802154_FC_TYPE_MAC_CMD:
302 dev_dbg(&sdata->dev->dev, "MAC COMMAND received\n");
303 mac_pkt = kzalloc_obj(*mac_pkt, GFP_ATOMIC);
304 if (!mac_pkt)
305 goto fail;
306
307 mac_pkt->skb = skb_get(skb);
308 mac_pkt->sdata = sdata;
309 netdev_hold(sdata->dev, &mac_pkt->dev_tracker, GFP_ATOMIC);
310 spin_lock(&sdata->local->rx_lock);
311 list_add_tail(&mac_pkt->node, &sdata->local->rx_mac_cmd_list);
312 spin_unlock(&sdata->local->rx_lock);
313 queue_work(sdata->local->mac_wq, &sdata->local->rx_mac_cmd_work);
314 return NET_RX_SUCCESS;
315
316 case IEEE802154_FC_TYPE_ACK:
317 goto fail;
318
319 case IEEE802154_FC_TYPE_DATA:
320 return ieee802154_deliver_skb(skb);
321 default:
322 pr_warn_ratelimited("ieee802154: bad frame received "
323 "(type = %d)\n", mac_cb(skb)->type);
324 goto fail;
325 }
326
327fail:
328 kfree_skb(skb);
329 return NET_RX_DROP;
330}
331
332static void
333ieee802154_print_addr(const char *name, const struct ieee802154_addr *addr)
334{
335 if (addr->mode == IEEE802154_ADDR_NONE) {
336 pr_debug("%s not present\n", name);
337 return;
338 }
339
340 pr_debug("%s PAN ID: %04x\n", name, le16_to_cpu(addr->pan_id));
341 if (addr->mode == IEEE802154_ADDR_SHORT) {
342 pr_debug("%s is short: %04x\n", name,
343 le16_to_cpu(addr->short_addr));
344 } else {
345 u64 hw = swab64((__force u64)addr->extended_addr);
346
347 pr_debug("%s is hardware: %8phC\n", name, &hw);
348 }
349}
350
351static int
352ieee802154_parse_frame_start(struct sk_buff *skb, struct ieee802154_hdr *hdr)
353{
354 int hlen;
355 struct ieee802154_mac_cb *cb = mac_cb(skb);
356
357 skb_reset_mac_header(skb);
358
359 hlen = ieee802154_hdr_pull(skb, hdr);
360 if (hlen < 0)
361 return -EINVAL;
362
363 skb->mac_len = hlen;
364
365 pr_debug("fc: %04x dsn: %02x\n", le16_to_cpup((__le16 *)&hdr->fc),
366 hdr->seq);
367
368 cb->type = hdr->fc.type;
369 cb->ackreq = hdr->fc.ack_request;
370 cb->secen = hdr->fc.security_enabled;
371
372 ieee802154_print_addr("destination", &hdr->dest);
373 ieee802154_print_addr("source", &hdr->source);
374
375 cb->source = hdr->source;
376 cb->dest = hdr->dest;
377
378 if (hdr->fc.security_enabled) {
379 u64 key;
380
381 pr_debug("seclevel %i\n", hdr->sec.level);
382
383 switch (hdr->sec.key_id_mode) {
384 case IEEE802154_SCF_KEY_IMPLICIT:
385 pr_debug("implicit key\n");
386 break;
387
388 case IEEE802154_SCF_KEY_INDEX:
389 pr_debug("key %02x\n", hdr->sec.key_id);
390 break;
391
392 case IEEE802154_SCF_KEY_SHORT_INDEX:
393 pr_debug("key %04x:%04x %02x\n",
394 le32_to_cpu(hdr->sec.short_src) >> 16,
395 le32_to_cpu(hdr->sec.short_src) & 0xffff,
396 hdr->sec.key_id);
397 break;
398
399 case IEEE802154_SCF_KEY_HW_INDEX:
400 key = swab64((__force u64)hdr->sec.extended_src);
401 pr_debug("key source %8phC %02x\n", &key,
402 hdr->sec.key_id);
403 break;
404 }
405 }
406
407 return 0;
408}
409
410static void
411__ieee802154_rx_handle_packet(struct ieee802154_local *local,
412 struct sk_buff *skb)
413{
414 int ret;
415 struct ieee802154_sub_if_data *sdata;
416 struct ieee802154_hdr hdr;
417 struct sk_buff *skb2;
418
419 ret = ieee802154_parse_frame_start(skb, &hdr);
420 if (ret) {
421 pr_debug("got invalid frame\n");
422 return;
423 }
424
425 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
426 if (sdata->wpan_dev.iftype == NL802154_IFTYPE_MONITOR)
427 continue;
428
429 if (!ieee802154_sdata_running(sdata))
430 continue;
431
432 /* Do not deliver packets received on interfaces expecting
433 * AACK=1 if the address filters where disabled.
434 */
435 if (local->hw.phy->filtering < IEEE802154_FILTERING_4_FRAME_FIELDS &&
436 sdata->required_filtering == IEEE802154_FILTERING_4_FRAME_FIELDS)
437 continue;
438
439 skb2 = skb_clone(skb, GFP_ATOMIC);
440 if (skb2) {
441 skb2->dev = sdata->dev;
442 ieee802154_subif_frame(sdata, skb2, &hdr);
443 }
444 }
445}
446
447static void
448ieee802154_monitors_rx(struct ieee802154_local *local, struct sk_buff *skb)
449{
450 struct sk_buff *skb2;
451 struct ieee802154_sub_if_data *sdata;
452
453 skb_reset_mac_header(skb);
454 skb->ip_summed = CHECKSUM_UNNECESSARY;
455 skb->pkt_type = PACKET_OTHERHOST;
456 skb->protocol = htons(ETH_P_IEEE802154);
457
458 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
459 if (sdata->wpan_dev.iftype != NL802154_IFTYPE_MONITOR)
460 continue;
461
462 if (!ieee802154_sdata_running(sdata))
463 continue;
464
465 skb2 = skb_clone(skb, GFP_ATOMIC);
466 if (skb2) {
467 skb2->dev = sdata->dev;
468 ieee802154_deliver_skb(skb2);
469
470 sdata->dev->stats.rx_packets++;
471 sdata->dev->stats.rx_bytes += skb->len;
472 }
473 }
474}
475
476void ieee802154_rx(struct ieee802154_local *local, struct sk_buff *skb)
477{
478 u16 crc;
479
480 WARN_ON_ONCE(softirq_count() == 0);
481
482 if (local->suspended)
483 goto free_skb;
484
485 /* TODO: When a transceiver omits the checksum here, we
486 * add an own calculated one. This is currently an ugly
487 * solution because the monitor needs a crc here.
488 */
489 if (local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM) {
490 crc = crc_ccitt(0, skb->data, skb->len);
491 put_unaligned_le16(crc, skb_put(skb, 2));
492 }
493
494 rcu_read_lock();
495
496 ieee802154_monitors_rx(local, skb);
497
498 /* Level 1 filtering: Check the FCS by software when relevant */
499 if (local->hw.phy->filtering == IEEE802154_FILTERING_NONE) {
500 crc = crc_ccitt(0, skb->data, skb->len);
501 if (crc)
502 goto drop;
503 }
504 /* remove crc */
505 skb_trim(skb, skb->len - 2);
506
507 __ieee802154_rx_handle_packet(local, skb);
508
509drop:
510 rcu_read_unlock();
511free_skb:
512 kfree_skb(skb);
513}
514
515void
516ieee802154_rx_irqsafe(struct ieee802154_hw *hw, struct sk_buff *skb, u8 lqi)
517{
518 struct ieee802154_local *local = hw_to_local(hw);
519 struct ieee802154_mac_cb *cb = mac_cb_init(skb);
520
521 cb->lqi = lqi;
522 skb->pkt_type = IEEE802154_RX_MSG;
523 skb_queue_tail(&local->skb_queue, skb);
524 tasklet_schedule(&local->tasklet);
525}
526EXPORT_SYMBOL(ieee802154_rx_irqsafe);