projects/linux·blob master · refs

1075 lines · 27.8 KiB

1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2002-2004, Instant802 Networks, Inc.
4 * Copyright 2008, Jouni Malinen <[email protected]>
5 * Copyright (C) 2016-2017 Intel Deutschland GmbH
6 * Copyright (C) 2020-2023 Intel Corporation
7 */
8
9#include <linux/netdevice.h>
10#include <linux/types.h>
11#include <linux/skbuff.h>
12#include <linux/compiler.h>
13#include <linux/ieee80211.h>
14#include <linux/gfp.h>
15#include <linux/unaligned.h>
16#include <net/mac80211.h>
17#include <crypto/aes.h>
18#include <crypto/utils.h>
19
20#include "ieee80211_i.h"
21#include "tkip.h"
22#include "aes_ccm.h"
23#include "aes_cmac.h"
24#include "aes_gmac.h"
25#include "aes_gcm.h"
26#include "wpa.h"
27
28ieee80211_tx_result
29ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
30{
31 u8 *data, *key, *mic;
32 size_t data_len;
33 unsigned int hdrlen;
34 struct ieee80211_hdr *hdr;
35 struct sk_buff *skb = tx->skb;
36 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
37 int tail;
38
39 hdr = (struct ieee80211_hdr *)skb->data;
40 if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
41 skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
42 return TX_CONTINUE;
43
44 hdrlen = ieee80211_hdrlen(hdr->frame_control);
45 if (skb->len < hdrlen)
46 return TX_DROP;
47
48 data = skb->data + hdrlen;
49 data_len = skb->len - hdrlen;
50
51 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
52 /* Need to use software crypto for the test */
53 info->control.hw_key = NULL;
54 }
55
56 if (info->control.hw_key &&
57 (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
58 ieee80211_hw_check(&tx->local->hw, SUPPORTS_TX_FRAG)) &&
59 !(tx->key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
60 IEEE80211_KEY_FLAG_PUT_MIC_SPACE))) {
61 /* hwaccel - with no need for SW-generated MMIC or MIC space */
62 return TX_CONTINUE;
63 }
64
65 tail = MICHAEL_MIC_LEN;
66 if (!info->control.hw_key)
67 tail += IEEE80211_TKIP_ICV_LEN;
68
69 if (WARN(skb_tailroom(skb) < tail ||
70 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN,
71 "mmic: not enough head/tail (%d/%d,%d/%d)\n",
72 skb_headroom(skb), IEEE80211_TKIP_IV_LEN,
73 skb_tailroom(skb), tail))
74 return TX_DROP;
75
76 mic = skb_put(skb, MICHAEL_MIC_LEN);
77
78 if (tx->key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) {
79 /* Zeroed MIC can help with debug */
80 memset(mic, 0, MICHAEL_MIC_LEN);
81 return TX_CONTINUE;
82 }
83
84 key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
85 michael_mic(key, hdr, data, data_len, mic);
86 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
87 mic[0]++;
88
89 return TX_CONTINUE;
90}
91
92
93ieee80211_rx_result
94ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
95{
96 u8 *data, *key = NULL;
97 size_t data_len;
98 unsigned int hdrlen;
99 u8 mic[MICHAEL_MIC_LEN];
100 struct sk_buff *skb = rx->skb;
101 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
102 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
103
104 /*
105 * it makes no sense to check for MIC errors on anything other
106 * than data frames.
107 */
108 if (!ieee80211_is_data_present(hdr->frame_control))
109 return RX_CONTINUE;
110
111 /*
112 * No way to verify the MIC if the hardware stripped it or
113 * the IV with the key index. In this case we have solely rely
114 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
115 * MIC failure report.
116 */
117 if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
118 if (status->flag & RX_FLAG_MMIC_ERROR)
119 goto mic_fail_no_key;
120
121 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
122 rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
123 goto update_iv;
124
125 return RX_CONTINUE;
126 }
127
128 /*
129 * Some hardware seems to generate Michael MIC failure reports; even
130 * though, the frame was not encrypted with TKIP and therefore has no
131 * MIC. Ignore the flag them to avoid triggering countermeasures.
132 */
133 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
134 !(status->flag & RX_FLAG_DECRYPTED))
135 return RX_CONTINUE;
136
137 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
138 /*
139 * APs with pairwise keys should never receive Michael MIC
140 * errors for non-zero keyidx because these are reserved for
141 * group keys and only the AP is sending real multicast
142 * frames in the BSS.
143 */
144 return RX_DROP_U_AP_RX_GROUPCAST;
145 }
146
147 if (status->flag & RX_FLAG_MMIC_ERROR)
148 goto mic_fail;
149
150 hdrlen = ieee80211_hdrlen(hdr->frame_control);
151 if (skb->len < hdrlen + MICHAEL_MIC_LEN)
152 return RX_DROP_U_SHORT_MMIC;
153
154 if (skb_linearize(rx->skb))
155 return RX_DROP_U_OOM;
156 hdr = (void *)skb->data;
157
158 data = skb->data + hdrlen;
159 data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
160 key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
161 michael_mic(key, hdr, data, data_len, mic);
162 if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN))
163 goto mic_fail;
164
165 /* remove Michael MIC from payload */
166 skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
167
168update_iv:
169 /* update IV in key information to be able to detect replays */
170 rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip.iv32;
171 rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip.iv16;
172
173 return RX_CONTINUE;
174
175mic_fail:
176 rx->key->u.tkip.mic_failures++;
177
178mic_fail_no_key:
179 /*
180 * In some cases the key can be unset - e.g. a multicast packet, in
181 * a driver that supports HW encryption. Send up the key idx only if
182 * the key is set.
183 */
184 cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2,
185 is_multicast_ether_addr(hdr->addr1) ?
186 NL80211_KEYTYPE_GROUP :
187 NL80211_KEYTYPE_PAIRWISE,
188 rx->key ? rx->key->conf.keyidx : -1,
189 NULL, GFP_ATOMIC);
190 return RX_DROP_U_MMIC_FAIL;
191}
192
193static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
194{
195 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
196 struct ieee80211_key *key = tx->key;
197 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
198 unsigned int hdrlen;
199 int len, tail;
200 u64 pn;
201 u8 *pos;
202
203 if (info->control.hw_key &&
204 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
205 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
206 /* hwaccel - with no need for software-generated IV */
207 return 0;
208 }
209
210 hdrlen = ieee80211_hdrlen(hdr->frame_control);
211 len = skb->len - hdrlen;
212
213 if (info->control.hw_key)
214 tail = 0;
215 else
216 tail = IEEE80211_TKIP_ICV_LEN;
217
218 if (WARN_ON(skb_tailroom(skb) < tail ||
219 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
220 return -1;
221
222 pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
223 memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
224 pos += hdrlen;
225
226 /* the HW only needs room for the IV, but not the actual IV */
227 if (info->control.hw_key &&
228 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
229 return 0;
230
231 /* Increase IV for the frame */
232 pn = atomic64_inc_return(&key->conf.tx_pn);
233 pos = ieee80211_tkip_add_iv(pos, &key->conf, pn);
234
235 /* hwaccel - with software IV */
236 if (info->control.hw_key)
237 return 0;
238
239 /* Add room for ICV */
240 skb_put(skb, IEEE80211_TKIP_ICV_LEN);
241
242 return ieee80211_tkip_encrypt_data(&tx->local->wep_tx_ctx,
243 key, skb, pos, len);
244}
245
246
247ieee80211_tx_result
248ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
249{
250 struct sk_buff *skb;
251
252 ieee80211_tx_set_protected(tx);
253
254 skb_queue_walk(&tx->skbs, skb) {
255 if (tkip_encrypt_skb(tx, skb) < 0)
256 return TX_DROP;
257 }
258
259 return TX_CONTINUE;
260}
261
262
263ieee80211_rx_result
264ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
265{
266 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
267 int hdrlen, res, hwaccel = 0;
268 struct ieee80211_key *key = rx->key;
269 struct sk_buff *skb = rx->skb;
270 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
271
272 hdrlen = ieee80211_hdrlen(hdr->frame_control);
273
274 if (!ieee80211_is_data(hdr->frame_control))
275 return RX_CONTINUE;
276
277 if (!rx->sta || skb->len - hdrlen < 12)
278 return RX_DROP_U_SHORT_TKIP;
279
280 /* it may be possible to optimize this a bit more */
281 if (skb_linearize(rx->skb))
282 return RX_DROP_U_OOM;
283 hdr = (void *)skb->data;
284
285 /*
286 * Let TKIP code verify IV, but skip decryption.
287 * In the case where hardware checks the IV as well,
288 * we don't even get here, see ieee80211_rx_h_decrypt()
289 */
290 if (status->flag & RX_FLAG_DECRYPTED)
291 hwaccel = 1;
292
293 res = ieee80211_tkip_decrypt_data(&rx->local->wep_rx_ctx,
294 key, skb->data + hdrlen,
295 skb->len - hdrlen, rx->sta->sta.addr,
296 hdr->addr1, hwaccel, rx->security_idx,
297 &rx->tkip.iv32,
298 &rx->tkip.iv16);
299 if (res != TKIP_DECRYPT_OK)
300 return RX_DROP_U_TKIP_FAIL;
301
302 /* Trim ICV */
303 if (!(status->flag & RX_FLAG_ICV_STRIPPED))
304 skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN);
305
306 /* Remove IV */
307 memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen);
308 skb_pull(skb, IEEE80211_TKIP_IV_LEN);
309
310 return RX_CONTINUE;
311}
312
313/*
314 * Calculate AAD for CCMP/GCMP, returning qos_tid since we
315 * need that in CCMP also for b_0.
316 */
317static u8 ccmp_gcmp_aad(struct sk_buff *skb, u8 *aad, bool spp_amsdu,
318 bool aad_nonce_computed)
319{
320 struct ieee80211_hdr *hdr = (void *)skb->data;
321 __le16 mask_fc;
322 int a4_included, mgmt;
323 u8 qos_tid;
324 u16 len_a = 22;
325
326 /*
327 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
328 * Retry, PwrMgt, MoreData, Order (if Qos Data); set Protected
329 */
330 mgmt = ieee80211_is_mgmt(hdr->frame_control);
331 mask_fc = hdr->frame_control;
332 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
333 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
334 if (!mgmt)
335 mask_fc &= ~cpu_to_le16(0x0070);
336 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
337
338 a4_included = ieee80211_has_a4(hdr->frame_control);
339 if (a4_included)
340 len_a += 6;
341
342 if (ieee80211_is_data_qos(hdr->frame_control)) {
343 qos_tid = *ieee80211_get_qos_ctl(hdr);
344
345 if (spp_amsdu)
346 qos_tid &= IEEE80211_QOS_CTL_TID_MASK |
347 IEEE80211_QOS_CTL_A_MSDU_PRESENT;
348 else
349 qos_tid &= IEEE80211_QOS_CTL_TID_MASK;
350
351 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_ORDER);
352 len_a += 2;
353 } else {
354 qos_tid = 0;
355 }
356
357 /* AAD (extra authenticate-only data) / masked 802.11 header
358 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
359 put_unaligned_be16(len_a, &aad[0]);
360 put_unaligned(mask_fc, (__le16 *)&aad[2]);
361 if (!aad_nonce_computed)
362 memcpy(&aad[4], &hdr->addrs, 3 * ETH_ALEN);
363
364 /* Mask Seq#, leave Frag# */
365 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
366 aad[23] = 0;
367
368 if (a4_included) {
369 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
370 aad[30] = qos_tid;
371 aad[31] = 0;
372 } else {
373 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
374 aad[24] = qos_tid;
375 }
376
377 return qos_tid;
378}
379
380static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad,
381 bool spp_amsdu, bool aad_nonce_computed)
382{
383 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
384 u8 qos_tid = ccmp_gcmp_aad(skb, aad, spp_amsdu, aad_nonce_computed);
385
386 /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC
387 * mode authentication are not allowed to collide, yet both are derived
388 * from this vector b_0. We only set L := 1 here to indicate that the
389 * data size can be represented in (L+1) bytes. The CCM layer will take
390 * care of storing the data length in the top (L+1) bytes and setting
391 * and clearing the other bits as is required to derive the two IVs.
392 */
393 b_0[0] = 0x1;
394
395 /* Nonce: Nonce Flags | A2 | PN
396 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
397 */
398 b_0[1] = qos_tid | (ieee80211_is_mgmt(hdr->frame_control) << 4);
399 if (!aad_nonce_computed)
400 memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
401 memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN);
402}
403
404static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
405{
406 hdr[0] = pn[5];
407 hdr[1] = pn[4];
408 hdr[2] = 0;
409 hdr[3] = 0x20 | (key_id << 6);
410 hdr[4] = pn[3];
411 hdr[5] = pn[2];
412 hdr[6] = pn[1];
413 hdr[7] = pn[0];
414}
415
416
417static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
418{
419 pn[0] = hdr[7];
420 pn[1] = hdr[6];
421 pn[2] = hdr[5];
422 pn[3] = hdr[4];
423 pn[4] = hdr[1];
424 pn[5] = hdr[0];
425}
426
427
428static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
429 unsigned int mic_len)
430{
431 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
432 struct ieee80211_key *key = tx->key;
433 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
434 int hdrlen, len, tail;
435 u8 *pos;
436 u8 pn[6];
437 u64 pn64;
438 u8 aad[CCM_AAD_LEN];
439 u8 b_0[AES_BLOCK_SIZE];
440
441 if (info->control.hw_key &&
442 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
443 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
444 !((info->control.hw_key->flags &
445 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
446 ieee80211_is_mgmt(hdr->frame_control))) {
447 /*
448 * hwaccel has no need for preallocated room for CCMP
449 * header or MIC fields
450 */
451 return 0;
452 }
453
454 hdrlen = ieee80211_hdrlen(hdr->frame_control);
455 len = skb->len - hdrlen;
456
457 if (info->control.hw_key)
458 tail = 0;
459 else
460 tail = mic_len;
461
462 if (WARN_ON(skb_tailroom(skb) < tail ||
463 skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN))
464 return -1;
465
466 pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN);
467 memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen);
468
469 /* the HW only needs room for the IV, but not the actual IV */
470 if (info->control.hw_key &&
471 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
472 return 0;
473
474 pos += hdrlen;
475
476 pn64 = atomic64_inc_return(&key->conf.tx_pn);
477
478 pn[5] = pn64;
479 pn[4] = pn64 >> 8;
480 pn[3] = pn64 >> 16;
481 pn[2] = pn64 >> 24;
482 pn[1] = pn64 >> 32;
483 pn[0] = pn64 >> 40;
484
485 ccmp_pn2hdr(pos, pn, key->conf.keyidx);
486
487 /* hwaccel - with software CCMP header */
488 if (info->control.hw_key)
489 return 0;
490
491 pos += IEEE80211_CCMP_HDR_LEN;
492 ccmp_special_blocks(skb, pn, b_0, aad,
493 key->conf.flags & IEEE80211_KEY_FLAG_SPP_AMSDU,
494 false);
495 return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
496 skb_put(skb, mic_len));
497}
498
499
500ieee80211_tx_result
501ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx,
502 unsigned int mic_len)
503{
504 struct sk_buff *skb;
505
506 ieee80211_tx_set_protected(tx);
507
508 skb_queue_walk(&tx->skbs, skb) {
509 if (ccmp_encrypt_skb(tx, skb, mic_len) < 0)
510 return TX_DROP;
511 }
512
513 return TX_CONTINUE;
514}
515
516
517ieee80211_rx_result
518ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
519 unsigned int mic_len)
520{
521 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
522 int hdrlen;
523 struct ieee80211_key *key = rx->key;
524 struct sk_buff *skb = rx->skb;
525 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
526 u8 pn[IEEE80211_CCMP_PN_LEN];
527 int data_len;
528 int queue;
529
530 hdrlen = ieee80211_hdrlen(hdr->frame_control);
531
532 if (!ieee80211_is_data(hdr->frame_control) &&
533 !ieee80211_is_robust_mgmt_frame(skb) &&
534 !ieee80211_require_encrypted_assoc(hdr->frame_control, rx->sta))
535 return RX_CONTINUE;
536
537 if (status->flag & RX_FLAG_DECRYPTED) {
538 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
539 return RX_DROP_U_SHORT_CCMP;
540 if (status->flag & RX_FLAG_MIC_STRIPPED)
541 mic_len = 0;
542 } else {
543 if (skb_linearize(rx->skb))
544 return RX_DROP_U_OOM;
545 }
546
547 /* reload hdr - skb might have been reallocated */
548 hdr = (void *)rx->skb->data;
549
550 data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
551 if (!rx->sta || data_len < 0)
552 return RX_DROP_U_SHORT_CCMP;
553
554 if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
555 int res;
556
557 ccmp_hdr2pn(pn, skb->data + hdrlen);
558
559 queue = rx->security_idx;
560
561 res = memcmp(pn, key->u.ccmp.rx_pn[queue],
562 IEEE80211_CCMP_PN_LEN);
563 if (res < 0 ||
564 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
565 key->u.ccmp.replays++;
566 return RX_DROP_U_REPLAY;
567 }
568
569 if (!(status->flag & RX_FLAG_DECRYPTED)) {
570 u8 aad[2 * AES_BLOCK_SIZE];
571 u8 b_0[AES_BLOCK_SIZE];
572 bool aad_nonce_computed = false;
573
574 if (is_unicast_ether_addr(hdr->addr1) &&
575 !ieee80211_is_data(hdr->frame_control)) {
576 /* AAD computation */
577 memcpy(&aad[4], rx->link_addrs, 3 * ETH_ALEN);
578 /* Nonce computation */
579 ether_addr_copy(&b_0[2],
580 &rx->link_addrs[ETH_ALEN]);
581 aad_nonce_computed = true;
582 }
583
584 /* hardware didn't decrypt/verify MIC */
585 ccmp_special_blocks(skb, pn, b_0, aad,
586 key->conf.flags & IEEE80211_KEY_FLAG_SPP_AMSDU,
587 aad_nonce_computed);
588
589 if (ieee80211_aes_ccm_decrypt(
590 key->u.ccmp.tfm, b_0, aad,
591 skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
592 data_len,
593 skb->data + skb->len - mic_len))
594 return RX_DROP_U_MIC_FAIL;
595 }
596
597 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
598 if (unlikely(ieee80211_is_frag(hdr)))
599 memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN);
600 }
601
602 /* Remove CCMP header and MIC */
603 if (pskb_trim(skb, skb->len - mic_len))
604 return RX_DROP_U_SHORT_CCMP_MIC;
605 memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
606 skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
607
608 return RX_CONTINUE;
609}
610
611static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad,
612 bool spp_amsdu, bool aad_nonce_computed)
613{
614 struct ieee80211_hdr *hdr = (void *)skb->data;
615
616 if (!aad_nonce_computed)
617 memcpy(j_0, hdr->addr2, ETH_ALEN);
618 memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
619
620 ccmp_gcmp_aad(skb, aad, spp_amsdu, aad_nonce_computed);
621}
622
623static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
624{
625 hdr[0] = pn[5];
626 hdr[1] = pn[4];
627 hdr[2] = 0;
628 hdr[3] = 0x20 | (key_id << 6);
629 hdr[4] = pn[3];
630 hdr[5] = pn[2];
631 hdr[6] = pn[1];
632 hdr[7] = pn[0];
633}
634
635static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
636{
637 pn[0] = hdr[7];
638 pn[1] = hdr[6];
639 pn[2] = hdr[5];
640 pn[3] = hdr[4];
641 pn[4] = hdr[1];
642 pn[5] = hdr[0];
643}
644
645static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
646{
647 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
648 struct ieee80211_key *key = tx->key;
649 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
650 int hdrlen, len, tail;
651 u8 *pos;
652 u8 pn[6];
653 u64 pn64;
654 u8 aad[GCM_AAD_LEN];
655 u8 j_0[AES_BLOCK_SIZE];
656
657 if (info->control.hw_key &&
658 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
659 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
660 !((info->control.hw_key->flags &
661 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
662 ieee80211_is_mgmt(hdr->frame_control))) {
663 /* hwaccel has no need for preallocated room for GCMP
664 * header or MIC fields
665 */
666 return 0;
667 }
668
669 hdrlen = ieee80211_hdrlen(hdr->frame_control);
670 len = skb->len - hdrlen;
671
672 if (info->control.hw_key)
673 tail = 0;
674 else
675 tail = IEEE80211_GCMP_MIC_LEN;
676
677 if (WARN_ON(skb_tailroom(skb) < tail ||
678 skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
679 return -1;
680
681 pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
682 memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
683 skb_set_network_header(skb, skb_network_offset(skb) +
684 IEEE80211_GCMP_HDR_LEN);
685
686 /* the HW only needs room for the IV, but not the actual IV */
687 if (info->control.hw_key &&
688 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
689 return 0;
690
691 pos += hdrlen;
692
693 pn64 = atomic64_inc_return(&key->conf.tx_pn);
694
695 pn[5] = pn64;
696 pn[4] = pn64 >> 8;
697 pn[3] = pn64 >> 16;
698 pn[2] = pn64 >> 24;
699 pn[1] = pn64 >> 32;
700 pn[0] = pn64 >> 40;
701
702 gcmp_pn2hdr(pos, pn, key->conf.keyidx);
703
704 /* hwaccel - with software GCMP header */
705 if (info->control.hw_key)
706 return 0;
707
708 pos += IEEE80211_GCMP_HDR_LEN;
709 gcmp_special_blocks(skb, pn, j_0, aad,
710 key->conf.flags & IEEE80211_KEY_FLAG_SPP_AMSDU,
711 false);
712 return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
713 skb_put(skb, IEEE80211_GCMP_MIC_LEN));
714}
715
716ieee80211_tx_result
717ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
718{
719 struct sk_buff *skb;
720
721 ieee80211_tx_set_protected(tx);
722
723 skb_queue_walk(&tx->skbs, skb) {
724 if (gcmp_encrypt_skb(tx, skb) < 0)
725 return TX_DROP;
726 }
727
728 return TX_CONTINUE;
729}
730
731ieee80211_rx_result
732ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
733{
734 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
735 int hdrlen;
736 struct ieee80211_key *key = rx->key;
737 struct sk_buff *skb = rx->skb;
738 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
739 u8 pn[IEEE80211_GCMP_PN_LEN];
740 int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN;
741
742 hdrlen = ieee80211_hdrlen(hdr->frame_control);
743
744 if (!ieee80211_is_data(hdr->frame_control) &&
745 !ieee80211_is_robust_mgmt_frame(skb) &&
746 !ieee80211_require_encrypted_assoc(hdr->frame_control, rx->sta))
747 return RX_CONTINUE;
748
749 if (status->flag & RX_FLAG_DECRYPTED) {
750 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
751 return RX_DROP_U_SHORT_GCMP;
752 if (status->flag & RX_FLAG_MIC_STRIPPED)
753 mic_len = 0;
754 } else {
755 if (skb_linearize(rx->skb))
756 return RX_DROP_U_OOM;
757 }
758
759 /* reload hdr - skb might have been reallocated */
760 hdr = (void *)rx->skb->data;
761
762 data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
763 if (!rx->sta || data_len < 0)
764 return RX_DROP_U_SHORT_GCMP;
765
766 if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
767 int res;
768
769 gcmp_hdr2pn(pn, skb->data + hdrlen);
770
771 queue = rx->security_idx;
772
773 res = memcmp(pn, key->u.gcmp.rx_pn[queue],
774 IEEE80211_GCMP_PN_LEN);
775 if (res < 0 ||
776 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
777 key->u.gcmp.replays++;
778 return RX_DROP_U_REPLAY;
779 }
780
781 if (!(status->flag & RX_FLAG_DECRYPTED)) {
782 u8 aad[2 * AES_BLOCK_SIZE];
783 u8 j_0[AES_BLOCK_SIZE];
784 bool aad_nonce_computed = false;
785
786 if (is_unicast_ether_addr(hdr->addr1) &&
787 !ieee80211_is_data(hdr->frame_control)) {
788 /* AAD computation */
789 memcpy(&aad[4], rx->link_addrs, 3 * ETH_ALEN);
790 /* Nonce computation */
791 ether_addr_copy(&j_0[0],
792 &rx->link_addrs[ETH_ALEN]);
793 aad_nonce_computed = true;
794 }
795 /* hardware didn't decrypt/verify MIC */
796 gcmp_special_blocks(skb, pn, j_0, aad,
797 key->conf.flags & IEEE80211_KEY_FLAG_SPP_AMSDU,
798 aad_nonce_computed);
799
800 if (ieee80211_aes_gcm_decrypt(
801 key->u.gcmp.tfm, j_0, aad,
802 skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
803 data_len,
804 skb->data + skb->len -
805 IEEE80211_GCMP_MIC_LEN))
806 return RX_DROP_U_MIC_FAIL;
807 }
808
809 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
810 if (unlikely(ieee80211_is_frag(hdr)))
811 memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN);
812 }
813
814 /* Remove GCMP header and MIC */
815 if (pskb_trim(skb, skb->len - mic_len))
816 return RX_DROP_U_SHORT_GCMP_MIC;
817 memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
818 skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
819
820 return RX_CONTINUE;
821}
822
823static void bip_aad(struct sk_buff *skb, u8 *aad)
824{
825 __le16 mask_fc;
826 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
827
828 /* BIP AAD: FC(masked) || A1 || A2 || A3 */
829
830 /* FC type/subtype */
831 /* Mask FC Retry, PwrMgt, MoreData flags to zero */
832 mask_fc = hdr->frame_control;
833 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
834 IEEE80211_FCTL_MOREDATA);
835 put_unaligned(mask_fc, (__le16 *) &aad[0]);
836 /* A1 || A2 || A3 */
837 memcpy(aad + 2, &hdr->addrs, 3 * ETH_ALEN);
838}
839
840
841static inline void bip_ipn_set64(u8 *d, u64 pn)
842{
843 *d++ = pn;
844 *d++ = pn >> 8;
845 *d++ = pn >> 16;
846 *d++ = pn >> 24;
847 *d++ = pn >> 32;
848 *d = pn >> 40;
849}
850
851static inline void bip_ipn_swap(u8 *d, const u8 *s)
852{
853 *d++ = s[5];
854 *d++ = s[4];
855 *d++ = s[3];
856 *d++ = s[2];
857 *d++ = s[1];
858 *d = s[0];
859}
860
861
862ieee80211_tx_result
863ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx,
864 unsigned int mic_len)
865{
866 struct sk_buff *skb;
867 struct ieee80211_tx_info *info;
868 struct ieee80211_key *key = tx->key;
869 struct ieee80211_mmie_var *mmie;
870 size_t mmie_len;
871 u8 aad[20];
872 u64 pn64;
873
874 if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
875 return TX_DROP;
876
877 skb = skb_peek(&tx->skbs);
878
879 info = IEEE80211_SKB_CB(skb);
880
881 if (info->control.hw_key &&
882 !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE))
883 return TX_CONTINUE;
884
885 mmie_len = sizeof(*mmie) + mic_len;
886
887 if (WARN_ON(skb_tailroom(skb) < mmie_len))
888 return TX_DROP;
889
890 mmie = skb_put(skb, mmie_len);
891 mmie->element_id = WLAN_EID_MMIE;
892 mmie->length = mmie_len - 2;
893 mmie->key_id = cpu_to_le16(key->conf.keyidx);
894
895 /* PN = PN + 1 */
896 pn64 = atomic64_inc_return(&key->conf.tx_pn);
897
898 bip_ipn_set64(mmie->sequence_number, pn64);
899
900 if (info->control.hw_key)
901 return TX_CONTINUE;
902
903 bip_aad(skb, aad);
904
905 ieee80211_aes_cmac(&key->u.aes_cmac.key, aad, skb->data + 24,
906 skb->len - 24, mmie->mic, mic_len);
907 return TX_CONTINUE;
908}
909
910ieee80211_rx_result
911ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx,
912 unsigned int mic_len)
913{
914 struct sk_buff *skb = rx->skb;
915 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
916 struct ieee80211_key *key = rx->key;
917 struct ieee80211_mmie_var *mmie;
918 size_t mmie_len;
919 u8 aad[20], mic[IEEE80211_CMAC_256_MIC_LEN], ipn[6];
920 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
921
922 if (!ieee80211_is_mgmt(hdr->frame_control))
923 return RX_CONTINUE;
924
925 mmie_len = sizeof(*mmie) + mic_len;
926
927 /* management frames are already linear */
928
929 if (skb->len < 24 + mmie_len)
930 return mic_len == IEEE80211_CMAC_128_MIC_LEN ?
931 RX_DROP_U_SHORT_CMAC : RX_DROP_U_SHORT_CMAC256;
932
933 mmie = (struct ieee80211_mmie_var *)(skb->data + skb->len - mmie_len);
934 if (mmie->element_id != WLAN_EID_MMIE ||
935 mmie->length != mmie_len - 2)
936 return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */
937
938 bip_ipn_swap(ipn, mmie->sequence_number);
939
940 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
941 key->u.aes_cmac.replays++;
942 return RX_DROP_U_REPLAY;
943 }
944
945 if (!(status->flag & RX_FLAG_DECRYPTED)) {
946 /* hardware didn't decrypt/verify MIC */
947 bip_aad(skb, aad);
948 ieee80211_aes_cmac(&key->u.aes_cmac.key, aad, skb->data + 24,
949 skb->len - 24, mic, mic_len);
950 if (crypto_memneq(mic, mmie->mic, mic_len)) {
951 key->u.aes_cmac.icverrors++;
952 return RX_DROP_U_MIC_FAIL;
953 }
954 }
955
956 memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
957
958 /* Remove MMIE */
959 skb_trim(skb, skb->len - mmie_len);
960
961 return RX_CONTINUE;
962}
963
964ieee80211_tx_result
965ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
966{
967 struct sk_buff *skb;
968 struct ieee80211_tx_info *info;
969 struct ieee80211_key *key = tx->key;
970 struct ieee80211_mmie_16 *mmie;
971 struct ieee80211_hdr *hdr;
972 u8 aad[GMAC_AAD_LEN];
973 u64 pn64;
974 u8 nonce[GMAC_NONCE_LEN];
975
976 if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
977 return TX_DROP;
978
979 skb = skb_peek(&tx->skbs);
980
981 info = IEEE80211_SKB_CB(skb);
982
983 if (info->control.hw_key &&
984 !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE))
985 return TX_CONTINUE;
986
987 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
988 return TX_DROP;
989
990 mmie = skb_put(skb, sizeof(*mmie));
991 mmie->element_id = WLAN_EID_MMIE;
992 mmie->length = sizeof(*mmie) - 2;
993 mmie->key_id = cpu_to_le16(key->conf.keyidx);
994
995 /* PN = PN + 1 */
996 pn64 = atomic64_inc_return(&key->conf.tx_pn);
997
998 bip_ipn_set64(mmie->sequence_number, pn64);
999
1000 if (info->control.hw_key)
1001 return TX_CONTINUE;
1002
1003 bip_aad(skb, aad);
1004
1005 hdr = (struct ieee80211_hdr *)skb->data;
1006 memcpy(nonce, hdr->addr2, ETH_ALEN);
1007 bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1008
1009 /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1010 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1011 skb->data + 24, skb->len - 24, mmie->mic) < 0)
1012 return TX_DROP;
1013
1014 return TX_CONTINUE;
1015}
1016
1017ieee80211_rx_result
1018ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1019{
1020 struct sk_buff *skb = rx->skb;
1021 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1022 struct ieee80211_key *key = rx->key;
1023 struct ieee80211_mmie_16 *mmie;
1024 u8 aad[GMAC_AAD_LEN], *mic, ipn[6], nonce[GMAC_NONCE_LEN];
1025 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1026
1027 if (!ieee80211_is_mgmt(hdr->frame_control))
1028 return RX_CONTINUE;
1029
1030 /* management frames are already linear */
1031
1032 if (skb->len < 24 + sizeof(*mmie))
1033 return RX_DROP_U_SHORT_GMAC;
1034
1035 mmie = (struct ieee80211_mmie_16 *)
1036 (skb->data + skb->len - sizeof(*mmie));
1037 if (mmie->element_id != WLAN_EID_MMIE ||
1038 mmie->length != sizeof(*mmie) - 2)
1039 return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */
1040
1041 bip_ipn_swap(ipn, mmie->sequence_number);
1042
1043 if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1044 key->u.aes_gmac.replays++;
1045 return RX_DROP_U_REPLAY;
1046 }
1047
1048 if (!(status->flag & RX_FLAG_DECRYPTED)) {
1049 /* hardware didn't decrypt/verify MIC */
1050 bip_aad(skb, aad);
1051
1052 memcpy(nonce, hdr->addr2, ETH_ALEN);
1053 memcpy(nonce + ETH_ALEN, ipn, 6);
1054
1055 mic = kmalloc(IEEE80211_GMAC_MIC_LEN, GFP_ATOMIC);
1056 if (!mic)
1057 return RX_DROP_U_OOM;
1058 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1059 skb->data + 24, skb->len - 24,
1060 mic) < 0 ||
1061 crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1062 key->u.aes_gmac.icverrors++;
1063 kfree(mic);
1064 return RX_DROP_U_MIC_FAIL;
1065 }
1066 kfree(mic);
1067 }
1068
1069 memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1070
1071 /* Remove MMIE */
1072 skb_trim(skb, skb->len - sizeof(*mmie));
1073
1074 return RX_CONTINUE;
1075}