1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2007-2012 Siemens AG
4 *
5 * Written by:
6 * Pavel Smolenskiy <pavel.smolenskiy@gmail.com>
7 * Maxim Gorbachyov <maxim.gorbachev@siemens.com>
8 * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
9 * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
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 <asm/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
24 static 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
32 void 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 mac_pkt = list_first_entry_or_null(&local->rx_beacon_list,
39 struct cfg802154_mac_pkt, node);
40 if (!mac_pkt)
41 return;
42
43 mac802154_process_beacon(local, mac_pkt->skb, mac_pkt->page, mac_pkt->channel);
44
45 list_del(&mac_pkt->node);
46 kfree_skb(mac_pkt->skb);
47 kfree(mac_pkt);
48 }
49
50 static bool mac802154_should_answer_beacon_req(struct ieee802154_local *local)
51 {
52 struct cfg802154_beacon_request *beacon_req;
53 unsigned int interval;
54
55 rcu_read_lock();
56 beacon_req = rcu_dereference(local->beacon_req);
57 if (!beacon_req) {
58 rcu_read_unlock();
59 return false;
60 }
61
62 interval = beacon_req->interval;
63 rcu_read_unlock();
64
65 if (!mac802154_is_beaconing(local))
66 return false;
67
68 return interval == IEEE802154_ACTIVE_SCAN_DURATION;
69 }
70
71 void mac802154_rx_mac_cmd_worker(struct work_struct *work)
72 {
73 struct ieee802154_local *local =
74 container_of(work, struct ieee802154_local, rx_mac_cmd_work);
75 struct cfg802154_mac_pkt *mac_pkt;
76 u8 mac_cmd;
77 int rc;
78
79 mac_pkt = list_first_entry_or_null(&local->rx_mac_cmd_list,
80 struct cfg802154_mac_pkt, node);
81 if (!mac_pkt)
82 return;
83
84 rc = ieee802154_get_mac_cmd(mac_pkt->skb, &mac_cmd);
85 if (rc)
86 goto out;
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 out:
126 list_del(&mac_pkt->node);
127 kfree_skb(mac_pkt->skb);
128 kfree(mac_pkt);
129 }
130
131 static int
132 ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata,
133 struct sk_buff *skb, const struct ieee802154_hdr *hdr)
134 {
135 struct wpan_phy *wpan_phy = sdata->local->hw.phy;
136 struct wpan_dev *wpan_dev = &sdata->wpan_dev;
137 struct cfg802154_mac_pkt *mac_pkt;
138 __le16 span, sshort;
139 int rc;
140
141 pr_debug("getting packet via slave interface %s\n", sdata->dev->name);
142
143 span = wpan_dev->pan_id;
144 sshort = wpan_dev->short_addr;
145
146 /* Level 3 filtering: Only beacons are accepted during scans */
147 if (sdata->required_filtering == IEEE802154_FILTERING_3_SCAN &&
148 sdata->required_filtering > wpan_phy->filtering) {
149 if (mac_cb(skb)->type != IEEE802154_FC_TYPE_BEACON) {
150 dev_dbg(&sdata->dev->dev,
151 "drop non-beacon frame (0x%x) during scan\n",
152 mac_cb(skb)->type);
153 goto fail;
154 }
155 }
156
157 switch (mac_cb(skb)->dest.mode) {
158 case IEEE802154_ADDR_NONE:
159 if (hdr->source.mode == IEEE802154_ADDR_NONE)
160 /* ACK comes with both addresses empty */
161 skb->pkt_type = PACKET_HOST;
162 else if (!wpan_dev->parent)
163 /* No dest means PAN coordinator is the recipient */
164 skb->pkt_type = PACKET_HOST;
165 else
166 /* We are not the PAN coordinator, just relaying */
167 skb->pkt_type = PACKET_OTHERHOST;
168 break;
169 case IEEE802154_ADDR_LONG:
170 if (mac_cb(skb)->dest.pan_id != span &&
171 mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST))
172 skb->pkt_type = PACKET_OTHERHOST;
173 else if (mac_cb(skb)->dest.extended_addr == wpan_dev->extended_addr)
174 skb->pkt_type = PACKET_HOST;
175 else
176 skb->pkt_type = PACKET_OTHERHOST;
177 break;
178 case IEEE802154_ADDR_SHORT:
179 if (mac_cb(skb)->dest.pan_id != span &&
180 mac_cb(skb)->dest.pan_id != cpu_to_le16(IEEE802154_PANID_BROADCAST))
181 skb->pkt_type = PACKET_OTHERHOST;
182 else if (mac_cb(skb)->dest.short_addr == sshort)
183 skb->pkt_type = PACKET_HOST;
184 else if (mac_cb(skb)->dest.short_addr ==
185 cpu_to_le16(IEEE802154_ADDR_BROADCAST))
186 skb->pkt_type = PACKET_BROADCAST;
187 else
188 skb->pkt_type = PACKET_OTHERHOST;
189 break;
190 default:
191 pr_debug("invalid dest mode\n");
192 goto fail;
193 }
194
195 skb->dev = sdata->dev;
196
197 /* TODO this should be moved after netif_receive_skb call, otherwise
198 * wireshark will show a mac header with security fields and the
199 * payload is already decrypted.
200 */
201 rc = mac802154_llsec_decrypt(&sdata->sec, skb);
202 if (rc) {
203 pr_debug("decryption failed: %i\n", rc);
204 goto fail;
205 }
206
207 sdata->dev->stats.rx_packets++;
208 sdata->dev->stats.rx_bytes += skb->len;
209
210 switch (mac_cb(skb)->type) {
211 case IEEE802154_FC_TYPE_BEACON:
212 dev_dbg(&sdata->dev->dev, "BEACON received\n");
213 if (!mac802154_is_scanning(sdata->local))
214 goto fail;
215
216 mac_pkt = kzalloc(sizeof(*mac_pkt), GFP_ATOMIC);
217 if (!mac_pkt)
218 goto fail;
219
220 mac_pkt->skb = skb_get(skb);
221 mac_pkt->sdata = sdata;
222 mac_pkt->page = sdata->local->scan_page;
223 mac_pkt->channel = sdata->local->scan_channel;
224 list_add_tail(&mac_pkt->node, &sdata->local->rx_beacon_list);
225 queue_work(sdata->local->mac_wq, &sdata->local->rx_beacon_work);
226 return NET_RX_SUCCESS;
227
228 case IEEE802154_FC_TYPE_MAC_CMD:
229 dev_dbg(&sdata->dev->dev, "MAC COMMAND received\n");
230 mac_pkt = kzalloc(sizeof(*mac_pkt), GFP_ATOMIC);
231 if (!mac_pkt)
232 goto fail;
233
234 mac_pkt->skb = skb_get(skb);
235 mac_pkt->sdata = sdata;
236 list_add_tail(&mac_pkt->node, &sdata->local->rx_mac_cmd_list);
237 queue_work(sdata->local->mac_wq, &sdata->local->rx_mac_cmd_work);
238 return NET_RX_SUCCESS;
239
240 case IEEE802154_FC_TYPE_ACK:
241 goto fail;
242
243 case IEEE802154_FC_TYPE_DATA:
244 return ieee802154_deliver_skb(skb);
245 default:
246 pr_warn_ratelimited("ieee802154: bad frame received "
247 "(type = %d)\n", mac_cb(skb)->type);
248 goto fail;
249 }
250
251 fail:
252 kfree_skb(skb);
253 return NET_RX_DROP;
254 }
255
256 static void
257 ieee802154_print_addr(const char *name, const struct ieee802154_addr *addr)
258 {
259 if (addr->mode == IEEE802154_ADDR_NONE) {
260 pr_debug("%s not present\n", name);
261 return;
262 }
263
264 pr_debug("%s PAN ID: %04x\n", name, le16_to_cpu(addr->pan_id));
265 if (addr->mode == IEEE802154_ADDR_SHORT) {
266 pr_debug("%s is short: %04x\n", name,
267 le16_to_cpu(addr->short_addr));
268 } else {
269 u64 hw = swab64((__force u64)addr->extended_addr);
270
271 pr_debug("%s is hardware: %8phC\n", name, &hw);
272 }
273 }
274
275 static int
276 ieee802154_parse_frame_start(struct sk_buff *skb, struct ieee802154_hdr *hdr)
277 {
278 int hlen;
279 struct ieee802154_mac_cb *cb = mac_cb(skb);
280
281 skb_reset_mac_header(skb);
282
283 hlen = ieee802154_hdr_pull(skb, hdr);
284 if (hlen < 0)
285 return -EINVAL;
286
287 skb->mac_len = hlen;
288
289 pr_debug("fc: %04x dsn: %02x\n", le16_to_cpup((__le16 *)&hdr->fc),
290 hdr->seq);
291
292 cb->type = hdr->fc.type;
293 cb->ackreq = hdr->fc.ack_request;
294 cb->secen = hdr->fc.security_enabled;
295
296 ieee802154_print_addr("destination", &hdr->dest);
297 ieee802154_print_addr("source", &hdr->source);
298
299 cb->source = hdr->source;
300 cb->dest = hdr->dest;
301
302 if (hdr->fc.security_enabled) {
303 u64 key;
304
305 pr_debug("seclevel %i\n", hdr->sec.level);
306
307 switch (hdr->sec.key_id_mode) {
308 case IEEE802154_SCF_KEY_IMPLICIT:
309 pr_debug("implicit key\n");
310 break;
311
312 case IEEE802154_SCF_KEY_INDEX:
313 pr_debug("key %02x\n", hdr->sec.key_id);
314 break;
315
316 case IEEE802154_SCF_KEY_SHORT_INDEX:
317 pr_debug("key %04x:%04x %02x\n",
318 le32_to_cpu(hdr->sec.short_src) >> 16,
319 le32_to_cpu(hdr->sec.short_src) & 0xffff,
320 hdr->sec.key_id);
321 break;
322
323 case IEEE802154_SCF_KEY_HW_INDEX:
324 key = swab64((__force u64)hdr->sec.extended_src);
325 pr_debug("key source %8phC %02x\n", &key,
326 hdr->sec.key_id);
327 break;
328 }
329 }
330
331 return 0;
332 }
333
334 static void
335 __ieee802154_rx_handle_packet(struct ieee802154_local *local,
336 struct sk_buff *skb)
337 {
338 int ret;
339 struct ieee802154_sub_if_data *sdata;
340 struct ieee802154_hdr hdr;
341 struct sk_buff *skb2;
342
343 ret = ieee802154_parse_frame_start(skb, &hdr);
344 if (ret) {
345 pr_debug("got invalid frame\n");
346 return;
347 }
348
349 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
350 if (sdata->wpan_dev.iftype == NL802154_IFTYPE_MONITOR)
351 continue;
352
353 if (!ieee802154_sdata_running(sdata))
354 continue;
355
356 /* Do not deliver packets received on interfaces expecting
357 * AACK=1 if the address filters where disabled.
358 */
359 if (local->hw.phy->filtering < IEEE802154_FILTERING_4_FRAME_FIELDS &&
360 sdata->required_filtering == IEEE802154_FILTERING_4_FRAME_FIELDS)
361 continue;
362
363 skb2 = skb_clone(skb, GFP_ATOMIC);
364 if (skb2) {
365 skb2->dev = sdata->dev;
366 ieee802154_subif_frame(sdata, skb2, &hdr);
367 }
368 }
369 }
370
371 static void
372 ieee802154_monitors_rx(struct ieee802154_local *local, struct sk_buff *skb)
373 {
374 struct sk_buff *skb2;
375 struct ieee802154_sub_if_data *sdata;
376
377 skb_reset_mac_header(skb);
378 skb->ip_summed = CHECKSUM_UNNECESSARY;
379 skb->pkt_type = PACKET_OTHERHOST;
380 skb->protocol = htons(ETH_P_IEEE802154);
381
382 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
383 if (sdata->wpan_dev.iftype != NL802154_IFTYPE_MONITOR)
384 continue;
385
386 if (!ieee802154_sdata_running(sdata))
387 continue;
388
389 skb2 = skb_clone(skb, GFP_ATOMIC);
390 if (skb2) {
391 skb2->dev = sdata->dev;
392 ieee802154_deliver_skb(skb2);
393
394 sdata->dev->stats.rx_packets++;
395 sdata->dev->stats.rx_bytes += skb->len;
396 }
397 }
398 }
399
400 void ieee802154_rx(struct ieee802154_local *local, struct sk_buff *skb)
401 {
402 u16 crc;
403
404 WARN_ON_ONCE(softirq_count() == 0);
405
406 if (local->suspended)
407 goto free_skb;
408
409 /* TODO: When a transceiver omits the checksum here, we
410 * add an own calculated one. This is currently an ugly
411 * solution because the monitor needs a crc here.
412 */
413 if (local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM) {
414 crc = crc_ccitt(0, skb->data, skb->len);
415 put_unaligned_le16(crc, skb_put(skb, 2));
416 }
417
418 rcu_read_lock();
419
420 ieee802154_monitors_rx(local, skb);
421
422 /* Level 1 filtering: Check the FCS by software when relevant */
423 if (local->hw.phy->filtering == IEEE802154_FILTERING_NONE) {
424 crc = crc_ccitt(0, skb->data, skb->len);
425 if (crc)
426 goto drop;
427 }
428 /* remove crc */
429 skb_trim(skb, skb->len - 2);
430
431 __ieee802154_rx_handle_packet(local, skb);
432
433 drop:
434 rcu_read_unlock();
435 free_skb:
436 kfree_skb(skb);
437 }
438
439 void
440 ieee802154_rx_irqsafe(struct ieee802154_hw *hw, struct sk_buff *skb, u8 lqi)
441 {
442 struct ieee802154_local *local = hw_to_local(hw);
443 struct ieee802154_mac_cb *cb = mac_cb_init(skb);
444
445 cb->lqi = lqi;
446 skb->pkt_type = IEEE802154_RX_MSG;
447 skb_queue_tail(&local->skb_queue, skb);
448 tasklet_schedule(&local->tasklet);
449 }
450 EXPORT_SYMBOL(ieee802154_rx_irqsafe);
451
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