xref: /openbmc/linux/net/mac80211/wpa.c (revision 0a94608f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2002-2004, Instant802 Networks, Inc.
4  * Copyright 2008, Jouni Malinen <j@w1.fi>
5  * Copyright (C) 2016-2017 Intel Deutschland GmbH
6  * Copyright (C) 2020-2021 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 <asm/unaligned.h>
16 #include <net/mac80211.h>
17 #include <crypto/aes.h>
18 #include <crypto/algapi.h>
19 
20 #include "ieee80211_i.h"
21 #include "michael.h"
22 #include "tkip.h"
23 #include "aes_ccm.h"
24 #include "aes_cmac.h"
25 #include "aes_gmac.h"
26 #include "aes_gcm.h"
27 #include "wpa.h"
28 
29 ieee80211_tx_result
30 ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
31 {
32 	u8 *data, *key, *mic;
33 	size_t data_len;
34 	unsigned int hdrlen;
35 	struct ieee80211_hdr *hdr;
36 	struct sk_buff *skb = tx->skb;
37 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
38 	int tail;
39 
40 	hdr = (struct ieee80211_hdr *)skb->data;
41 	if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
42 	    skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
43 		return TX_CONTINUE;
44 
45 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
46 	if (skb->len < hdrlen)
47 		return TX_DROP;
48 
49 	data = skb->data + hdrlen;
50 	data_len = skb->len - hdrlen;
51 
52 	if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
53 		/* Need to use software crypto for the test */
54 		info->control.hw_key = NULL;
55 	}
56 
57 	if (info->control.hw_key &&
58 	    (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
59 	     ieee80211_hw_check(&tx->local->hw, SUPPORTS_TX_FRAG)) &&
60 	    !(tx->key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
61 				     IEEE80211_KEY_FLAG_PUT_MIC_SPACE))) {
62 		/* hwaccel - with no need for SW-generated MMIC or MIC space */
63 		return TX_CONTINUE;
64 	}
65 
66 	tail = MICHAEL_MIC_LEN;
67 	if (!info->control.hw_key)
68 		tail += IEEE80211_TKIP_ICV_LEN;
69 
70 	if (WARN(skb_tailroom(skb) < tail ||
71 		 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN,
72 		 "mmic: not enough head/tail (%d/%d,%d/%d)\n",
73 		 skb_headroom(skb), IEEE80211_TKIP_IV_LEN,
74 		 skb_tailroom(skb), tail))
75 		return TX_DROP;
76 
77 	mic = skb_put(skb, MICHAEL_MIC_LEN);
78 
79 	if (tx->key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) {
80 		/* Zeroed MIC can help with debug */
81 		memset(mic, 0, MICHAEL_MIC_LEN);
82 		return TX_CONTINUE;
83 	}
84 
85 	key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
86 	michael_mic(key, hdr, data, data_len, mic);
87 	if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
88 		mic[0]++;
89 
90 	return TX_CONTINUE;
91 }
92 
93 
94 ieee80211_rx_result
95 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
96 {
97 	u8 *data, *key = NULL;
98 	size_t data_len;
99 	unsigned int hdrlen;
100 	u8 mic[MICHAEL_MIC_LEN];
101 	struct sk_buff *skb = rx->skb;
102 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
103 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
104 
105 	/*
106 	 * it makes no sense to check for MIC errors on anything other
107 	 * than data frames.
108 	 */
109 	if (!ieee80211_is_data_present(hdr->frame_control))
110 		return RX_CONTINUE;
111 
112 	/*
113 	 * No way to verify the MIC if the hardware stripped it or
114 	 * the IV with the key index. In this case we have solely rely
115 	 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
116 	 * MIC failure report.
117 	 */
118 	if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
119 		if (status->flag & RX_FLAG_MMIC_ERROR)
120 			goto mic_fail_no_key;
121 
122 		if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
123 		    rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
124 			goto update_iv;
125 
126 		return RX_CONTINUE;
127 	}
128 
129 	/*
130 	 * Some hardware seems to generate Michael MIC failure reports; even
131 	 * though, the frame was not encrypted with TKIP and therefore has no
132 	 * MIC. Ignore the flag them to avoid triggering countermeasures.
133 	 */
134 	if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
135 	    !(status->flag & RX_FLAG_DECRYPTED))
136 		return RX_CONTINUE;
137 
138 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
139 		/*
140 		 * APs with pairwise keys should never receive Michael MIC
141 		 * errors for non-zero keyidx because these are reserved for
142 		 * group keys and only the AP is sending real multicast
143 		 * frames in the BSS.
144 		 */
145 		return RX_DROP_UNUSABLE;
146 	}
147 
148 	if (status->flag & RX_FLAG_MMIC_ERROR)
149 		goto mic_fail;
150 
151 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
152 	if (skb->len < hdrlen + MICHAEL_MIC_LEN)
153 		return RX_DROP_UNUSABLE;
154 
155 	if (skb_linearize(rx->skb))
156 		return RX_DROP_UNUSABLE;
157 	hdr = (void *)skb->data;
158 
159 	data = skb->data + hdrlen;
160 	data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
161 	key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
162 	michael_mic(key, hdr, data, data_len, mic);
163 	if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN))
164 		goto mic_fail;
165 
166 	/* remove Michael MIC from payload */
167 	skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
168 
169 update_iv:
170 	/* update IV in key information to be able to detect replays */
171 	rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip.iv32;
172 	rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip.iv16;
173 
174 	return RX_CONTINUE;
175 
176 mic_fail:
177 	rx->key->u.tkip.mic_failures++;
178 
179 mic_fail_no_key:
180 	/*
181 	 * In some cases the key can be unset - e.g. a multicast packet, in
182 	 * a driver that supports HW encryption. Send up the key idx only if
183 	 * the key is set.
184 	 */
185 	cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2,
186 				     is_multicast_ether_addr(hdr->addr1) ?
187 				     NL80211_KEYTYPE_GROUP :
188 				     NL80211_KEYTYPE_PAIRWISE,
189 				     rx->key ? rx->key->conf.keyidx : -1,
190 				     NULL, GFP_ATOMIC);
191 	return RX_DROP_UNUSABLE;
192 }
193 
194 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
195 {
196 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
197 	struct ieee80211_key *key = tx->key;
198 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
199 	unsigned int hdrlen;
200 	int len, tail;
201 	u64 pn;
202 	u8 *pos;
203 
204 	if (info->control.hw_key &&
205 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
206 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
207 		/* hwaccel - with no need for software-generated IV */
208 		return 0;
209 	}
210 
211 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
212 	len = skb->len - hdrlen;
213 
214 	if (info->control.hw_key)
215 		tail = 0;
216 	else
217 		tail = IEEE80211_TKIP_ICV_LEN;
218 
219 	if (WARN_ON(skb_tailroom(skb) < tail ||
220 		    skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
221 		return -1;
222 
223 	pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
224 	memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
225 	pos += hdrlen;
226 
227 	/* the HW only needs room for the IV, but not the actual IV */
228 	if (info->control.hw_key &&
229 	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
230 		return 0;
231 
232 	/* Increase IV for the frame */
233 	pn = atomic64_inc_return(&key->conf.tx_pn);
234 	pos = ieee80211_tkip_add_iv(pos, &key->conf, pn);
235 
236 	/* hwaccel - with software IV */
237 	if (info->control.hw_key)
238 		return 0;
239 
240 	/* Add room for ICV */
241 	skb_put(skb, IEEE80211_TKIP_ICV_LEN);
242 
243 	return ieee80211_tkip_encrypt_data(&tx->local->wep_tx_ctx,
244 					   key, skb, pos, len);
245 }
246 
247 
248 ieee80211_tx_result
249 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
250 {
251 	struct sk_buff *skb;
252 
253 	ieee80211_tx_set_protected(tx);
254 
255 	skb_queue_walk(&tx->skbs, skb) {
256 		if (tkip_encrypt_skb(tx, skb) < 0)
257 			return TX_DROP;
258 	}
259 
260 	return TX_CONTINUE;
261 }
262 
263 
264 ieee80211_rx_result
265 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
266 {
267 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
268 	int hdrlen, res, hwaccel = 0;
269 	struct ieee80211_key *key = rx->key;
270 	struct sk_buff *skb = rx->skb;
271 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
272 
273 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
274 
275 	if (!ieee80211_is_data(hdr->frame_control))
276 		return RX_CONTINUE;
277 
278 	if (!rx->sta || skb->len - hdrlen < 12)
279 		return RX_DROP_UNUSABLE;
280 
281 	/* it may be possible to optimize this a bit more */
282 	if (skb_linearize(rx->skb))
283 		return RX_DROP_UNUSABLE;
284 	hdr = (void *)skb->data;
285 
286 	/*
287 	 * Let TKIP code verify IV, but skip decryption.
288 	 * In the case where hardware checks the IV as well,
289 	 * we don't even get here, see ieee80211_rx_h_decrypt()
290 	 */
291 	if (status->flag & RX_FLAG_DECRYPTED)
292 		hwaccel = 1;
293 
294 	res = ieee80211_tkip_decrypt_data(&rx->local->wep_rx_ctx,
295 					  key, skb->data + hdrlen,
296 					  skb->len - hdrlen, rx->sta->sta.addr,
297 					  hdr->addr1, hwaccel, rx->security_idx,
298 					  &rx->tkip.iv32,
299 					  &rx->tkip.iv16);
300 	if (res != TKIP_DECRYPT_OK)
301 		return RX_DROP_UNUSABLE;
302 
303 	/* Trim ICV */
304 	if (!(status->flag & RX_FLAG_ICV_STRIPPED))
305 		skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN);
306 
307 	/* Remove IV */
308 	memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen);
309 	skb_pull(skb, IEEE80211_TKIP_IV_LEN);
310 
311 	return RX_CONTINUE;
312 }
313 
314 
315 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad)
316 {
317 	__le16 mask_fc;
318 	int a4_included, mgmt;
319 	u8 qos_tid;
320 	u16 len_a;
321 	unsigned int hdrlen;
322 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
323 
324 	/*
325 	 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
326 	 * Retry, PwrMgt, MoreData; set Protected
327 	 */
328 	mgmt = ieee80211_is_mgmt(hdr->frame_control);
329 	mask_fc = hdr->frame_control;
330 	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
331 				IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
332 	if (!mgmt)
333 		mask_fc &= ~cpu_to_le16(0x0070);
334 	mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
335 
336 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
337 	len_a = hdrlen - 2;
338 	a4_included = ieee80211_has_a4(hdr->frame_control);
339 
340 	if (ieee80211_is_data_qos(hdr->frame_control))
341 		qos_tid = ieee80211_get_tid(hdr);
342 	else
343 		qos_tid = 0;
344 
345 	/* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC
346 	 * mode authentication are not allowed to collide, yet both are derived
347 	 * from this vector b_0. We only set L := 1 here to indicate that the
348 	 * data size can be represented in (L+1) bytes. The CCM layer will take
349 	 * care of storing the data length in the top (L+1) bytes and setting
350 	 * and clearing the other bits as is required to derive the two IVs.
351 	 */
352 	b_0[0] = 0x1;
353 
354 	/* Nonce: Nonce Flags | A2 | PN
355 	 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
356 	 */
357 	b_0[1] = qos_tid | (mgmt << 4);
358 	memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
359 	memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN);
360 
361 	/* AAD (extra authenticate-only data) / masked 802.11 header
362 	 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
363 	put_unaligned_be16(len_a, &aad[0]);
364 	put_unaligned(mask_fc, (__le16 *)&aad[2]);
365 	memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
366 
367 	/* Mask Seq#, leave Frag# */
368 	aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
369 	aad[23] = 0;
370 
371 	if (a4_included) {
372 		memcpy(&aad[24], hdr->addr4, ETH_ALEN);
373 		aad[30] = qos_tid;
374 		aad[31] = 0;
375 	} else {
376 		memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
377 		aad[24] = qos_tid;
378 	}
379 }
380 
381 
382 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
383 {
384 	hdr[0] = pn[5];
385 	hdr[1] = pn[4];
386 	hdr[2] = 0;
387 	hdr[3] = 0x20 | (key_id << 6);
388 	hdr[4] = pn[3];
389 	hdr[5] = pn[2];
390 	hdr[6] = pn[1];
391 	hdr[7] = pn[0];
392 }
393 
394 
395 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
396 {
397 	pn[0] = hdr[7];
398 	pn[1] = hdr[6];
399 	pn[2] = hdr[5];
400 	pn[3] = hdr[4];
401 	pn[4] = hdr[1];
402 	pn[5] = hdr[0];
403 }
404 
405 
406 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
407 			    unsigned int mic_len)
408 {
409 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
410 	struct ieee80211_key *key = tx->key;
411 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
412 	int hdrlen, len, tail;
413 	u8 *pos;
414 	u8 pn[6];
415 	u64 pn64;
416 	u8 aad[CCM_AAD_LEN];
417 	u8 b_0[AES_BLOCK_SIZE];
418 
419 	if (info->control.hw_key &&
420 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
421 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
422 	    !((info->control.hw_key->flags &
423 	       IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
424 	      ieee80211_is_mgmt(hdr->frame_control))) {
425 		/*
426 		 * hwaccel has no need for preallocated room for CCMP
427 		 * header or MIC fields
428 		 */
429 		return 0;
430 	}
431 
432 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
433 	len = skb->len - hdrlen;
434 
435 	if (info->control.hw_key)
436 		tail = 0;
437 	else
438 		tail = mic_len;
439 
440 	if (WARN_ON(skb_tailroom(skb) < tail ||
441 		    skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN))
442 		return -1;
443 
444 	pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN);
445 	memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen);
446 
447 	/* the HW only needs room for the IV, but not the actual IV */
448 	if (info->control.hw_key &&
449 	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
450 		return 0;
451 
452 	pos += hdrlen;
453 
454 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
455 
456 	pn[5] = pn64;
457 	pn[4] = pn64 >> 8;
458 	pn[3] = pn64 >> 16;
459 	pn[2] = pn64 >> 24;
460 	pn[1] = pn64 >> 32;
461 	pn[0] = pn64 >> 40;
462 
463 	ccmp_pn2hdr(pos, pn, key->conf.keyidx);
464 
465 	/* hwaccel - with software CCMP header */
466 	if (info->control.hw_key)
467 		return 0;
468 
469 	pos += IEEE80211_CCMP_HDR_LEN;
470 	ccmp_special_blocks(skb, pn, b_0, aad);
471 	return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
472 					 skb_put(skb, mic_len));
473 }
474 
475 
476 ieee80211_tx_result
477 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx,
478 			      unsigned int mic_len)
479 {
480 	struct sk_buff *skb;
481 
482 	ieee80211_tx_set_protected(tx);
483 
484 	skb_queue_walk(&tx->skbs, skb) {
485 		if (ccmp_encrypt_skb(tx, skb, mic_len) < 0)
486 			return TX_DROP;
487 	}
488 
489 	return TX_CONTINUE;
490 }
491 
492 
493 ieee80211_rx_result
494 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
495 			      unsigned int mic_len)
496 {
497 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
498 	int hdrlen;
499 	struct ieee80211_key *key = rx->key;
500 	struct sk_buff *skb = rx->skb;
501 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
502 	u8 pn[IEEE80211_CCMP_PN_LEN];
503 	int data_len;
504 	int queue;
505 
506 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
507 
508 	if (!ieee80211_is_data(hdr->frame_control) &&
509 	    !ieee80211_is_robust_mgmt_frame(skb))
510 		return RX_CONTINUE;
511 
512 	if (status->flag & RX_FLAG_DECRYPTED) {
513 		if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
514 			return RX_DROP_UNUSABLE;
515 		if (status->flag & RX_FLAG_MIC_STRIPPED)
516 			mic_len = 0;
517 	} else {
518 		if (skb_linearize(rx->skb))
519 			return RX_DROP_UNUSABLE;
520 	}
521 
522 	/* reload hdr - skb might have been reallocated */
523 	hdr = (void *)rx->skb->data;
524 
525 	data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
526 	if (!rx->sta || data_len < 0)
527 		return RX_DROP_UNUSABLE;
528 
529 	if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
530 		int res;
531 
532 		ccmp_hdr2pn(pn, skb->data + hdrlen);
533 
534 		queue = rx->security_idx;
535 
536 		res = memcmp(pn, key->u.ccmp.rx_pn[queue],
537 			     IEEE80211_CCMP_PN_LEN);
538 		if (res < 0 ||
539 		    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
540 			key->u.ccmp.replays++;
541 			return RX_DROP_UNUSABLE;
542 		}
543 
544 		if (!(status->flag & RX_FLAG_DECRYPTED)) {
545 			u8 aad[2 * AES_BLOCK_SIZE];
546 			u8 b_0[AES_BLOCK_SIZE];
547 			/* hardware didn't decrypt/verify MIC */
548 			ccmp_special_blocks(skb, pn, b_0, aad);
549 
550 			if (ieee80211_aes_ccm_decrypt(
551 				    key->u.ccmp.tfm, b_0, aad,
552 				    skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
553 				    data_len,
554 				    skb->data + skb->len - mic_len))
555 				return RX_DROP_UNUSABLE;
556 		}
557 
558 		memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
559 		if (unlikely(ieee80211_is_frag(hdr)))
560 			memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN);
561 	}
562 
563 	/* Remove CCMP header and MIC */
564 	if (pskb_trim(skb, skb->len - mic_len))
565 		return RX_DROP_UNUSABLE;
566 	memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
567 	skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
568 
569 	return RX_CONTINUE;
570 }
571 
572 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
573 {
574 	__le16 mask_fc;
575 	u8 qos_tid;
576 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
577 
578 	memcpy(j_0, hdr->addr2, ETH_ALEN);
579 	memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
580 	j_0[13] = 0;
581 	j_0[14] = 0;
582 	j_0[AES_BLOCK_SIZE - 1] = 0x01;
583 
584 	/* AAD (extra authenticate-only data) / masked 802.11 header
585 	 * FC | A1 | A2 | A3 | SC | [A4] | [QC]
586 	 */
587 	put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
588 	/* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
589 	 * Retry, PwrMgt, MoreData; set Protected
590 	 */
591 	mask_fc = hdr->frame_control;
592 	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
593 				IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
594 	if (!ieee80211_is_mgmt(hdr->frame_control))
595 		mask_fc &= ~cpu_to_le16(0x0070);
596 	mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
597 
598 	put_unaligned(mask_fc, (__le16 *)&aad[2]);
599 	memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
600 
601 	/* Mask Seq#, leave Frag# */
602 	aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
603 	aad[23] = 0;
604 
605 	if (ieee80211_is_data_qos(hdr->frame_control))
606 		qos_tid = ieee80211_get_tid(hdr);
607 	else
608 		qos_tid = 0;
609 
610 	if (ieee80211_has_a4(hdr->frame_control)) {
611 		memcpy(&aad[24], hdr->addr4, ETH_ALEN);
612 		aad[30] = qos_tid;
613 		aad[31] = 0;
614 	} else {
615 		memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
616 		aad[24] = qos_tid;
617 	}
618 }
619 
620 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
621 {
622 	hdr[0] = pn[5];
623 	hdr[1] = pn[4];
624 	hdr[2] = 0;
625 	hdr[3] = 0x20 | (key_id << 6);
626 	hdr[4] = pn[3];
627 	hdr[5] = pn[2];
628 	hdr[6] = pn[1];
629 	hdr[7] = pn[0];
630 }
631 
632 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
633 {
634 	pn[0] = hdr[7];
635 	pn[1] = hdr[6];
636 	pn[2] = hdr[5];
637 	pn[3] = hdr[4];
638 	pn[4] = hdr[1];
639 	pn[5] = hdr[0];
640 }
641 
642 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
643 {
644 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
645 	struct ieee80211_key *key = tx->key;
646 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
647 	int hdrlen, len, tail;
648 	u8 *pos;
649 	u8 pn[6];
650 	u64 pn64;
651 	u8 aad[GCM_AAD_LEN];
652 	u8 j_0[AES_BLOCK_SIZE];
653 
654 	if (info->control.hw_key &&
655 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
656 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
657 	    !((info->control.hw_key->flags &
658 	       IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
659 	      ieee80211_is_mgmt(hdr->frame_control))) {
660 		/* hwaccel has no need for preallocated room for GCMP
661 		 * header or MIC fields
662 		 */
663 		return 0;
664 	}
665 
666 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
667 	len = skb->len - hdrlen;
668 
669 	if (info->control.hw_key)
670 		tail = 0;
671 	else
672 		tail = IEEE80211_GCMP_MIC_LEN;
673 
674 	if (WARN_ON(skb_tailroom(skb) < tail ||
675 		    skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
676 		return -1;
677 
678 	pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
679 	memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
680 	skb_set_network_header(skb, skb_network_offset(skb) +
681 				    IEEE80211_GCMP_HDR_LEN);
682 
683 	/* the HW only needs room for the IV, but not the actual IV */
684 	if (info->control.hw_key &&
685 	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
686 		return 0;
687 
688 	pos += hdrlen;
689 
690 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
691 
692 	pn[5] = pn64;
693 	pn[4] = pn64 >> 8;
694 	pn[3] = pn64 >> 16;
695 	pn[2] = pn64 >> 24;
696 	pn[1] = pn64 >> 32;
697 	pn[0] = pn64 >> 40;
698 
699 	gcmp_pn2hdr(pos, pn, key->conf.keyidx);
700 
701 	/* hwaccel - with software GCMP header */
702 	if (info->control.hw_key)
703 		return 0;
704 
705 	pos += IEEE80211_GCMP_HDR_LEN;
706 	gcmp_special_blocks(skb, pn, j_0, aad);
707 	return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
708 					 skb_put(skb, IEEE80211_GCMP_MIC_LEN));
709 }
710 
711 ieee80211_tx_result
712 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
713 {
714 	struct sk_buff *skb;
715 
716 	ieee80211_tx_set_protected(tx);
717 
718 	skb_queue_walk(&tx->skbs, skb) {
719 		if (gcmp_encrypt_skb(tx, skb) < 0)
720 			return TX_DROP;
721 	}
722 
723 	return TX_CONTINUE;
724 }
725 
726 ieee80211_rx_result
727 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
728 {
729 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
730 	int hdrlen;
731 	struct ieee80211_key *key = rx->key;
732 	struct sk_buff *skb = rx->skb;
733 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
734 	u8 pn[IEEE80211_GCMP_PN_LEN];
735 	int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN;
736 
737 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
738 
739 	if (!ieee80211_is_data(hdr->frame_control) &&
740 	    !ieee80211_is_robust_mgmt_frame(skb))
741 		return RX_CONTINUE;
742 
743 	if (status->flag & RX_FLAG_DECRYPTED) {
744 		if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
745 			return RX_DROP_UNUSABLE;
746 		if (status->flag & RX_FLAG_MIC_STRIPPED)
747 			mic_len = 0;
748 	} else {
749 		if (skb_linearize(rx->skb))
750 			return RX_DROP_UNUSABLE;
751 	}
752 
753 	/* reload hdr - skb might have been reallocated */
754 	hdr = (void *)rx->skb->data;
755 
756 	data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
757 	if (!rx->sta || data_len < 0)
758 		return RX_DROP_UNUSABLE;
759 
760 	if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
761 		int res;
762 
763 		gcmp_hdr2pn(pn, skb->data + hdrlen);
764 
765 		queue = rx->security_idx;
766 
767 		res = memcmp(pn, key->u.gcmp.rx_pn[queue],
768 			     IEEE80211_GCMP_PN_LEN);
769 		if (res < 0 ||
770 		    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
771 			key->u.gcmp.replays++;
772 			return RX_DROP_UNUSABLE;
773 		}
774 
775 		if (!(status->flag & RX_FLAG_DECRYPTED)) {
776 			u8 aad[2 * AES_BLOCK_SIZE];
777 			u8 j_0[AES_BLOCK_SIZE];
778 			/* hardware didn't decrypt/verify MIC */
779 			gcmp_special_blocks(skb, pn, j_0, aad);
780 
781 			if (ieee80211_aes_gcm_decrypt(
782 				    key->u.gcmp.tfm, j_0, aad,
783 				    skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
784 				    data_len,
785 				    skb->data + skb->len -
786 				    IEEE80211_GCMP_MIC_LEN))
787 				return RX_DROP_UNUSABLE;
788 		}
789 
790 		memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
791 		if (unlikely(ieee80211_is_frag(hdr)))
792 			memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN);
793 	}
794 
795 	/* Remove GCMP header and MIC */
796 	if (pskb_trim(skb, skb->len - mic_len))
797 		return RX_DROP_UNUSABLE;
798 	memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
799 	skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
800 
801 	return RX_CONTINUE;
802 }
803 
804 static ieee80211_tx_result
805 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
806 			    struct sk_buff *skb)
807 {
808 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
809 	struct ieee80211_key *key = tx->key;
810 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
811 	int hdrlen;
812 	u8 *pos, iv_len = key->conf.iv_len;
813 
814 	if (info->control.hw_key &&
815 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
816 		/* hwaccel has no need for preallocated head room */
817 		return TX_CONTINUE;
818 	}
819 
820 	if (unlikely(skb_headroom(skb) < iv_len &&
821 		     pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
822 		return TX_DROP;
823 
824 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
825 
826 	pos = skb_push(skb, iv_len);
827 	memmove(pos, pos + iv_len, hdrlen);
828 
829 	return TX_CONTINUE;
830 }
831 
832 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
833 {
834 	int i;
835 
836 	/* pn is little endian */
837 	for (i = len - 1; i >= 0; i--) {
838 		if (pn1[i] < pn2[i])
839 			return -1;
840 		else if (pn1[i] > pn2[i])
841 			return 1;
842 	}
843 
844 	return 0;
845 }
846 
847 static ieee80211_rx_result
848 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
849 {
850 	struct ieee80211_key *key = rx->key;
851 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
852 	const struct ieee80211_cipher_scheme *cs = NULL;
853 	int hdrlen = ieee80211_hdrlen(hdr->frame_control);
854 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
855 	int data_len;
856 	u8 *rx_pn;
857 	u8 *skb_pn;
858 	u8 qos_tid;
859 
860 	if (!rx->sta || !rx->sta->cipher_scheme ||
861 	    !(status->flag & RX_FLAG_DECRYPTED))
862 		return RX_DROP_UNUSABLE;
863 
864 	if (!ieee80211_is_data(hdr->frame_control))
865 		return RX_CONTINUE;
866 
867 	cs = rx->sta->cipher_scheme;
868 
869 	data_len = rx->skb->len - hdrlen - cs->hdr_len;
870 
871 	if (data_len < 0)
872 		return RX_DROP_UNUSABLE;
873 
874 	if (ieee80211_is_data_qos(hdr->frame_control))
875 		qos_tid = ieee80211_get_tid(hdr);
876 	else
877 		qos_tid = 0;
878 
879 	if (skb_linearize(rx->skb))
880 		return RX_DROP_UNUSABLE;
881 
882 	rx_pn = key->u.gen.rx_pn[qos_tid];
883 	skb_pn = rx->skb->data + hdrlen + cs->pn_off;
884 
885 	if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
886 		return RX_DROP_UNUSABLE;
887 
888 	memcpy(rx_pn, skb_pn, cs->pn_len);
889 
890 	/* remove security header and MIC */
891 	if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
892 		return RX_DROP_UNUSABLE;
893 
894 	memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
895 	skb_pull(rx->skb, cs->hdr_len);
896 
897 	return RX_CONTINUE;
898 }
899 
900 static void bip_aad(struct sk_buff *skb, u8 *aad)
901 {
902 	__le16 mask_fc;
903 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
904 
905 	/* BIP AAD: FC(masked) || A1 || A2 || A3 */
906 
907 	/* FC type/subtype */
908 	/* Mask FC Retry, PwrMgt, MoreData flags to zero */
909 	mask_fc = hdr->frame_control;
910 	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
911 				IEEE80211_FCTL_MOREDATA);
912 	put_unaligned(mask_fc, (__le16 *) &aad[0]);
913 	/* A1 || A2 || A3 */
914 	memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
915 }
916 
917 
918 static inline void bip_ipn_set64(u8 *d, u64 pn)
919 {
920 	*d++ = pn;
921 	*d++ = pn >> 8;
922 	*d++ = pn >> 16;
923 	*d++ = pn >> 24;
924 	*d++ = pn >> 32;
925 	*d = pn >> 40;
926 }
927 
928 static inline void bip_ipn_swap(u8 *d, const u8 *s)
929 {
930 	*d++ = s[5];
931 	*d++ = s[4];
932 	*d++ = s[3];
933 	*d++ = s[2];
934 	*d++ = s[1];
935 	*d = s[0];
936 }
937 
938 
939 ieee80211_tx_result
940 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
941 {
942 	struct sk_buff *skb;
943 	struct ieee80211_tx_info *info;
944 	struct ieee80211_key *key = tx->key;
945 	struct ieee80211_mmie *mmie;
946 	u8 aad[20];
947 	u64 pn64;
948 
949 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
950 		return TX_DROP;
951 
952 	skb = skb_peek(&tx->skbs);
953 
954 	info = IEEE80211_SKB_CB(skb);
955 
956 	if (info->control.hw_key &&
957 	    !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE))
958 		return TX_CONTINUE;
959 
960 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
961 		return TX_DROP;
962 
963 	mmie = skb_put(skb, sizeof(*mmie));
964 	mmie->element_id = WLAN_EID_MMIE;
965 	mmie->length = sizeof(*mmie) - 2;
966 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
967 
968 	/* PN = PN + 1 */
969 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
970 
971 	bip_ipn_set64(mmie->sequence_number, pn64);
972 
973 	if (info->control.hw_key)
974 		return TX_CONTINUE;
975 
976 	bip_aad(skb, aad);
977 
978 	/*
979 	 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
980 	 */
981 	ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
982 			   skb->data + 24, skb->len - 24, mmie->mic);
983 
984 	return TX_CONTINUE;
985 }
986 
987 ieee80211_tx_result
988 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
989 {
990 	struct sk_buff *skb;
991 	struct ieee80211_tx_info *info;
992 	struct ieee80211_key *key = tx->key;
993 	struct ieee80211_mmie_16 *mmie;
994 	u8 aad[20];
995 	u64 pn64;
996 
997 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
998 		return TX_DROP;
999 
1000 	skb = skb_peek(&tx->skbs);
1001 
1002 	info = IEEE80211_SKB_CB(skb);
1003 
1004 	if (info->control.hw_key)
1005 		return TX_CONTINUE;
1006 
1007 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1008 		return TX_DROP;
1009 
1010 	mmie = skb_put(skb, sizeof(*mmie));
1011 	mmie->element_id = WLAN_EID_MMIE;
1012 	mmie->length = sizeof(*mmie) - 2;
1013 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
1014 
1015 	/* PN = PN + 1 */
1016 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
1017 
1018 	bip_ipn_set64(mmie->sequence_number, pn64);
1019 
1020 	bip_aad(skb, aad);
1021 
1022 	/* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1023 	 */
1024 	ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1025 			       skb->data + 24, skb->len - 24, mmie->mic);
1026 
1027 	return TX_CONTINUE;
1028 }
1029 
1030 ieee80211_rx_result
1031 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1032 {
1033 	struct sk_buff *skb = rx->skb;
1034 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1035 	struct ieee80211_key *key = rx->key;
1036 	struct ieee80211_mmie *mmie;
1037 	u8 aad[20], mic[8], ipn[6];
1038 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1039 
1040 	if (!ieee80211_is_mgmt(hdr->frame_control))
1041 		return RX_CONTINUE;
1042 
1043 	/* management frames are already linear */
1044 
1045 	if (skb->len < 24 + sizeof(*mmie))
1046 		return RX_DROP_UNUSABLE;
1047 
1048 	mmie = (struct ieee80211_mmie *)
1049 		(skb->data + skb->len - sizeof(*mmie));
1050 	if (mmie->element_id != WLAN_EID_MMIE ||
1051 	    mmie->length != sizeof(*mmie) - 2)
1052 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1053 
1054 	bip_ipn_swap(ipn, mmie->sequence_number);
1055 
1056 	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1057 		key->u.aes_cmac.replays++;
1058 		return RX_DROP_UNUSABLE;
1059 	}
1060 
1061 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1062 		/* hardware didn't decrypt/verify MIC */
1063 		bip_aad(skb, aad);
1064 		ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1065 				   skb->data + 24, skb->len - 24, mic);
1066 		if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1067 			key->u.aes_cmac.icverrors++;
1068 			return RX_DROP_UNUSABLE;
1069 		}
1070 	}
1071 
1072 	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1073 
1074 	/* Remove MMIE */
1075 	skb_trim(skb, skb->len - sizeof(*mmie));
1076 
1077 	return RX_CONTINUE;
1078 }
1079 
1080 ieee80211_rx_result
1081 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1082 {
1083 	struct sk_buff *skb = rx->skb;
1084 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1085 	struct ieee80211_key *key = rx->key;
1086 	struct ieee80211_mmie_16 *mmie;
1087 	u8 aad[20], mic[16], ipn[6];
1088 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1089 
1090 	if (!ieee80211_is_mgmt(hdr->frame_control))
1091 		return RX_CONTINUE;
1092 
1093 	/* management frames are already linear */
1094 
1095 	if (skb->len < 24 + sizeof(*mmie))
1096 		return RX_DROP_UNUSABLE;
1097 
1098 	mmie = (struct ieee80211_mmie_16 *)
1099 		(skb->data + skb->len - sizeof(*mmie));
1100 	if (mmie->element_id != WLAN_EID_MMIE ||
1101 	    mmie->length != sizeof(*mmie) - 2)
1102 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1103 
1104 	bip_ipn_swap(ipn, mmie->sequence_number);
1105 
1106 	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1107 		key->u.aes_cmac.replays++;
1108 		return RX_DROP_UNUSABLE;
1109 	}
1110 
1111 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1112 		/* hardware didn't decrypt/verify MIC */
1113 		bip_aad(skb, aad);
1114 		ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1115 				       skb->data + 24, skb->len - 24, mic);
1116 		if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1117 			key->u.aes_cmac.icverrors++;
1118 			return RX_DROP_UNUSABLE;
1119 		}
1120 	}
1121 
1122 	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1123 
1124 	/* Remove MMIE */
1125 	skb_trim(skb, skb->len - sizeof(*mmie));
1126 
1127 	return RX_CONTINUE;
1128 }
1129 
1130 ieee80211_tx_result
1131 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1132 {
1133 	struct sk_buff *skb;
1134 	struct ieee80211_tx_info *info;
1135 	struct ieee80211_key *key = tx->key;
1136 	struct ieee80211_mmie_16 *mmie;
1137 	struct ieee80211_hdr *hdr;
1138 	u8 aad[GMAC_AAD_LEN];
1139 	u64 pn64;
1140 	u8 nonce[GMAC_NONCE_LEN];
1141 
1142 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1143 		return TX_DROP;
1144 
1145 	skb = skb_peek(&tx->skbs);
1146 
1147 	info = IEEE80211_SKB_CB(skb);
1148 
1149 	if (info->control.hw_key)
1150 		return TX_CONTINUE;
1151 
1152 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1153 		return TX_DROP;
1154 
1155 	mmie = skb_put(skb, sizeof(*mmie));
1156 	mmie->element_id = WLAN_EID_MMIE;
1157 	mmie->length = sizeof(*mmie) - 2;
1158 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
1159 
1160 	/* PN = PN + 1 */
1161 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
1162 
1163 	bip_ipn_set64(mmie->sequence_number, pn64);
1164 
1165 	bip_aad(skb, aad);
1166 
1167 	hdr = (struct ieee80211_hdr *)skb->data;
1168 	memcpy(nonce, hdr->addr2, ETH_ALEN);
1169 	bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1170 
1171 	/* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1172 	if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1173 			       skb->data + 24, skb->len - 24, mmie->mic) < 0)
1174 		return TX_DROP;
1175 
1176 	return TX_CONTINUE;
1177 }
1178 
1179 ieee80211_rx_result
1180 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1181 {
1182 	struct sk_buff *skb = rx->skb;
1183 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1184 	struct ieee80211_key *key = rx->key;
1185 	struct ieee80211_mmie_16 *mmie;
1186 	u8 aad[GMAC_AAD_LEN], *mic, ipn[6], nonce[GMAC_NONCE_LEN];
1187 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1188 
1189 	if (!ieee80211_is_mgmt(hdr->frame_control))
1190 		return RX_CONTINUE;
1191 
1192 	/* management frames are already linear */
1193 
1194 	if (skb->len < 24 + sizeof(*mmie))
1195 		return RX_DROP_UNUSABLE;
1196 
1197 	mmie = (struct ieee80211_mmie_16 *)
1198 		(skb->data + skb->len - sizeof(*mmie));
1199 	if (mmie->element_id != WLAN_EID_MMIE ||
1200 	    mmie->length != sizeof(*mmie) - 2)
1201 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1202 
1203 	bip_ipn_swap(ipn, mmie->sequence_number);
1204 
1205 	if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1206 		key->u.aes_gmac.replays++;
1207 		return RX_DROP_UNUSABLE;
1208 	}
1209 
1210 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1211 		/* hardware didn't decrypt/verify MIC */
1212 		bip_aad(skb, aad);
1213 
1214 		memcpy(nonce, hdr->addr2, ETH_ALEN);
1215 		memcpy(nonce + ETH_ALEN, ipn, 6);
1216 
1217 		mic = kmalloc(GMAC_MIC_LEN, GFP_ATOMIC);
1218 		if (!mic)
1219 			return RX_DROP_UNUSABLE;
1220 		if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1221 				       skb->data + 24, skb->len - 24,
1222 				       mic) < 0 ||
1223 		    crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1224 			key->u.aes_gmac.icverrors++;
1225 			kfree(mic);
1226 			return RX_DROP_UNUSABLE;
1227 		}
1228 		kfree(mic);
1229 	}
1230 
1231 	memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1232 
1233 	/* Remove MMIE */
1234 	skb_trim(skb, skb->len - sizeof(*mmie));
1235 
1236 	return RX_CONTINUE;
1237 }
1238 
1239 ieee80211_tx_result
1240 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1241 {
1242 	struct sk_buff *skb;
1243 	struct ieee80211_tx_info *info = NULL;
1244 	ieee80211_tx_result res;
1245 
1246 	skb_queue_walk(&tx->skbs, skb) {
1247 		info  = IEEE80211_SKB_CB(skb);
1248 
1249 		/* handle hw-only algorithm */
1250 		if (!info->control.hw_key)
1251 			return TX_DROP;
1252 
1253 		if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1254 			res = ieee80211_crypto_cs_encrypt(tx, skb);
1255 			if (res != TX_CONTINUE)
1256 				return res;
1257 		}
1258 	}
1259 
1260 	ieee80211_tx_set_protected(tx);
1261 
1262 	return TX_CONTINUE;
1263 }
1264 
1265 ieee80211_rx_result
1266 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1267 {
1268 	if (rx->sta && rx->sta->cipher_scheme)
1269 		return ieee80211_crypto_cs_decrypt(rx);
1270 
1271 	return RX_DROP_UNUSABLE;
1272 }
1273