xref: /openbmc/linux/net/mac80211/wpa.c (revision eb3fcf00)
1 /*
2  * Copyright 2002-2004, Instant802 Networks, Inc.
3  * Copyright 2008, Jouni Malinen <j@w1.fi>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  */
9 
10 #include <linux/netdevice.h>
11 #include <linux/types.h>
12 #include <linux/skbuff.h>
13 #include <linux/compiler.h>
14 #include <linux/ieee80211.h>
15 #include <linux/gfp.h>
16 #include <asm/unaligned.h>
17 #include <net/mac80211.h>
18 #include <crypto/aes.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 	     tx->local->ops->set_frag_threshold) &&
60 	    !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
61 		/* hwaccel - with no need for SW-generated MMIC */
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 	key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
77 	mic = skb_put(skb, MICHAEL_MIC_LEN);
78 	michael_mic(key, hdr, data, data_len, mic);
79 	if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
80 		mic[0]++;
81 
82 	return TX_CONTINUE;
83 }
84 
85 
86 ieee80211_rx_result
87 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
88 {
89 	u8 *data, *key = NULL;
90 	size_t data_len;
91 	unsigned int hdrlen;
92 	u8 mic[MICHAEL_MIC_LEN];
93 	struct sk_buff *skb = rx->skb;
94 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
95 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
96 
97 	/*
98 	 * it makes no sense to check for MIC errors on anything other
99 	 * than data frames.
100 	 */
101 	if (!ieee80211_is_data_present(hdr->frame_control))
102 		return RX_CONTINUE;
103 
104 	/*
105 	 * No way to verify the MIC if the hardware stripped it or
106 	 * the IV with the key index. In this case we have solely rely
107 	 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
108 	 * MIC failure report.
109 	 */
110 	if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
111 		if (status->flag & RX_FLAG_MMIC_ERROR)
112 			goto mic_fail_no_key;
113 
114 		if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
115 		    rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
116 			goto update_iv;
117 
118 		return RX_CONTINUE;
119 	}
120 
121 	/*
122 	 * Some hardware seems to generate Michael MIC failure reports; even
123 	 * though, the frame was not encrypted with TKIP and therefore has no
124 	 * MIC. Ignore the flag them to avoid triggering countermeasures.
125 	 */
126 	if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
127 	    !(status->flag & RX_FLAG_DECRYPTED))
128 		return RX_CONTINUE;
129 
130 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
131 		/*
132 		 * APs with pairwise keys should never receive Michael MIC
133 		 * errors for non-zero keyidx because these are reserved for
134 		 * group keys and only the AP is sending real multicast
135 		 * frames in the BSS.
136 		 */
137 		return RX_DROP_UNUSABLE;
138 	}
139 
140 	if (status->flag & RX_FLAG_MMIC_ERROR)
141 		goto mic_fail;
142 
143 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
144 	if (skb->len < hdrlen + MICHAEL_MIC_LEN)
145 		return RX_DROP_UNUSABLE;
146 
147 	if (skb_linearize(rx->skb))
148 		return RX_DROP_UNUSABLE;
149 	hdr = (void *)skb->data;
150 
151 	data = skb->data + hdrlen;
152 	data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
153 	key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
154 	michael_mic(key, hdr, data, data_len, mic);
155 	if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0)
156 		goto mic_fail;
157 
158 	/* remove Michael MIC from payload */
159 	skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
160 
161 update_iv:
162 	/* update IV in key information to be able to detect replays */
163 	rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
164 	rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
165 
166 	return RX_CONTINUE;
167 
168 mic_fail:
169 	rx->key->u.tkip.mic_failures++;
170 
171 mic_fail_no_key:
172 	/*
173 	 * In some cases the key can be unset - e.g. a multicast packet, in
174 	 * a driver that supports HW encryption. Send up the key idx only if
175 	 * the key is set.
176 	 */
177 	mac80211_ev_michael_mic_failure(rx->sdata,
178 					rx->key ? rx->key->conf.keyidx : -1,
179 					(void *) skb->data, NULL, GFP_ATOMIC);
180 	return RX_DROP_UNUSABLE;
181 }
182 
183 
184 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
185 {
186 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
187 	struct ieee80211_key *key = tx->key;
188 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
189 	unsigned int hdrlen;
190 	int len, tail;
191 	u8 *pos;
192 
193 	if (info->control.hw_key &&
194 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
195 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
196 		/* hwaccel - with no need for software-generated IV */
197 		return 0;
198 	}
199 
200 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
201 	len = skb->len - hdrlen;
202 
203 	if (info->control.hw_key)
204 		tail = 0;
205 	else
206 		tail = IEEE80211_TKIP_ICV_LEN;
207 
208 	if (WARN_ON(skb_tailroom(skb) < tail ||
209 		    skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
210 		return -1;
211 
212 	pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
213 	memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
214 	pos += hdrlen;
215 
216 	/* the HW only needs room for the IV, but not the actual IV */
217 	if (info->control.hw_key &&
218 	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
219 		return 0;
220 
221 	/* Increase IV for the frame */
222 	spin_lock(&key->u.tkip.txlock);
223 	key->u.tkip.tx.iv16++;
224 	if (key->u.tkip.tx.iv16 == 0)
225 		key->u.tkip.tx.iv32++;
226 	pos = ieee80211_tkip_add_iv(pos, key);
227 	spin_unlock(&key->u.tkip.txlock);
228 
229 	/* hwaccel - with software IV */
230 	if (info->control.hw_key)
231 		return 0;
232 
233 	/* Add room for ICV */
234 	skb_put(skb, IEEE80211_TKIP_ICV_LEN);
235 
236 	return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
237 					   key, skb, pos, len);
238 }
239 
240 
241 ieee80211_tx_result
242 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
243 {
244 	struct sk_buff *skb;
245 
246 	ieee80211_tx_set_protected(tx);
247 
248 	skb_queue_walk(&tx->skbs, skb) {
249 		if (tkip_encrypt_skb(tx, skb) < 0)
250 			return TX_DROP;
251 	}
252 
253 	return TX_CONTINUE;
254 }
255 
256 
257 ieee80211_rx_result
258 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
259 {
260 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
261 	int hdrlen, res, hwaccel = 0;
262 	struct ieee80211_key *key = rx->key;
263 	struct sk_buff *skb = rx->skb;
264 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
265 
266 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
267 
268 	if (!ieee80211_is_data(hdr->frame_control))
269 		return RX_CONTINUE;
270 
271 	if (!rx->sta || skb->len - hdrlen < 12)
272 		return RX_DROP_UNUSABLE;
273 
274 	/* it may be possible to optimize this a bit more */
275 	if (skb_linearize(rx->skb))
276 		return RX_DROP_UNUSABLE;
277 	hdr = (void *)skb->data;
278 
279 	/*
280 	 * Let TKIP code verify IV, but skip decryption.
281 	 * In the case where hardware checks the IV as well,
282 	 * we don't even get here, see ieee80211_rx_h_decrypt()
283 	 */
284 	if (status->flag & RX_FLAG_DECRYPTED)
285 		hwaccel = 1;
286 
287 	res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
288 					  key, skb->data + hdrlen,
289 					  skb->len - hdrlen, rx->sta->sta.addr,
290 					  hdr->addr1, hwaccel, rx->security_idx,
291 					  &rx->tkip_iv32,
292 					  &rx->tkip_iv16);
293 	if (res != TKIP_DECRYPT_OK)
294 		return RX_DROP_UNUSABLE;
295 
296 	/* Trim ICV */
297 	skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN);
298 
299 	/* Remove IV */
300 	memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen);
301 	skb_pull(skb, IEEE80211_TKIP_IV_LEN);
302 
303 	return RX_CONTINUE;
304 }
305 
306 
307 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad)
308 {
309 	__le16 mask_fc;
310 	int a4_included, mgmt;
311 	u8 qos_tid;
312 	u16 len_a;
313 	unsigned int hdrlen;
314 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
315 
316 	/*
317 	 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
318 	 * Retry, PwrMgt, MoreData; set Protected
319 	 */
320 	mgmt = ieee80211_is_mgmt(hdr->frame_control);
321 	mask_fc = hdr->frame_control;
322 	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
323 				IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
324 	if (!mgmt)
325 		mask_fc &= ~cpu_to_le16(0x0070);
326 	mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
327 
328 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
329 	len_a = hdrlen - 2;
330 	a4_included = ieee80211_has_a4(hdr->frame_control);
331 
332 	if (ieee80211_is_data_qos(hdr->frame_control))
333 		qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
334 	else
335 		qos_tid = 0;
336 
337 	/* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC
338 	 * mode authentication are not allowed to collide, yet both are derived
339 	 * from this vector b_0. We only set L := 1 here to indicate that the
340 	 * data size can be represented in (L+1) bytes. The CCM layer will take
341 	 * care of storing the data length in the top (L+1) bytes and setting
342 	 * and clearing the other bits as is required to derive the two IVs.
343 	 */
344 	b_0[0] = 0x1;
345 
346 	/* Nonce: Nonce Flags | A2 | PN
347 	 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
348 	 */
349 	b_0[1] = qos_tid | (mgmt << 4);
350 	memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
351 	memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN);
352 
353 	/* AAD (extra authenticate-only data) / masked 802.11 header
354 	 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
355 	put_unaligned_be16(len_a, &aad[0]);
356 	put_unaligned(mask_fc, (__le16 *)&aad[2]);
357 	memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
358 
359 	/* Mask Seq#, leave Frag# */
360 	aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
361 	aad[23] = 0;
362 
363 	if (a4_included) {
364 		memcpy(&aad[24], hdr->addr4, ETH_ALEN);
365 		aad[30] = qos_tid;
366 		aad[31] = 0;
367 	} else {
368 		memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
369 		aad[24] = qos_tid;
370 	}
371 }
372 
373 
374 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
375 {
376 	hdr[0] = pn[5];
377 	hdr[1] = pn[4];
378 	hdr[2] = 0;
379 	hdr[3] = 0x20 | (key_id << 6);
380 	hdr[4] = pn[3];
381 	hdr[5] = pn[2];
382 	hdr[6] = pn[1];
383 	hdr[7] = pn[0];
384 }
385 
386 
387 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
388 {
389 	pn[0] = hdr[7];
390 	pn[1] = hdr[6];
391 	pn[2] = hdr[5];
392 	pn[3] = hdr[4];
393 	pn[4] = hdr[1];
394 	pn[5] = hdr[0];
395 }
396 
397 
398 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
399 			    unsigned int mic_len)
400 {
401 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
402 	struct ieee80211_key *key = tx->key;
403 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
404 	int hdrlen, len, tail;
405 	u8 *pos;
406 	u8 pn[6];
407 	u64 pn64;
408 	u8 aad[2 * AES_BLOCK_SIZE];
409 	u8 b_0[AES_BLOCK_SIZE];
410 
411 	if (info->control.hw_key &&
412 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
413 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
414 	    !((info->control.hw_key->flags &
415 	       IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
416 	      ieee80211_is_mgmt(hdr->frame_control))) {
417 		/*
418 		 * hwaccel has no need for preallocated room for CCMP
419 		 * header or MIC fields
420 		 */
421 		return 0;
422 	}
423 
424 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
425 	len = skb->len - hdrlen;
426 
427 	if (info->control.hw_key)
428 		tail = 0;
429 	else
430 		tail = mic_len;
431 
432 	if (WARN_ON(skb_tailroom(skb) < tail ||
433 		    skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN))
434 		return -1;
435 
436 	pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN);
437 	memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen);
438 
439 	/* the HW only needs room for the IV, but not the actual IV */
440 	if (info->control.hw_key &&
441 	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
442 		return 0;
443 
444 	hdr = (struct ieee80211_hdr *) pos;
445 	pos += hdrlen;
446 
447 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
448 
449 	pn[5] = pn64;
450 	pn[4] = pn64 >> 8;
451 	pn[3] = pn64 >> 16;
452 	pn[2] = pn64 >> 24;
453 	pn[1] = pn64 >> 32;
454 	pn[0] = pn64 >> 40;
455 
456 	ccmp_pn2hdr(pos, pn, key->conf.keyidx);
457 
458 	/* hwaccel - with software CCMP header */
459 	if (info->control.hw_key)
460 		return 0;
461 
462 	pos += IEEE80211_CCMP_HDR_LEN;
463 	ccmp_special_blocks(skb, pn, b_0, aad);
464 	ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
465 				  skb_put(skb, mic_len), mic_len);
466 
467 	return 0;
468 }
469 
470 
471 ieee80211_tx_result
472 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx,
473 			      unsigned int mic_len)
474 {
475 	struct sk_buff *skb;
476 
477 	ieee80211_tx_set_protected(tx);
478 
479 	skb_queue_walk(&tx->skbs, skb) {
480 		if (ccmp_encrypt_skb(tx, skb, mic_len) < 0)
481 			return TX_DROP;
482 	}
483 
484 	return TX_CONTINUE;
485 }
486 
487 
488 ieee80211_rx_result
489 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
490 			      unsigned int mic_len)
491 {
492 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
493 	int hdrlen;
494 	struct ieee80211_key *key = rx->key;
495 	struct sk_buff *skb = rx->skb;
496 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
497 	u8 pn[IEEE80211_CCMP_PN_LEN];
498 	int data_len;
499 	int queue;
500 
501 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
502 
503 	if (!ieee80211_is_data(hdr->frame_control) &&
504 	    !ieee80211_is_robust_mgmt_frame(skb))
505 		return RX_CONTINUE;
506 
507 	data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
508 	if (!rx->sta || data_len < 0)
509 		return RX_DROP_UNUSABLE;
510 
511 	if (status->flag & RX_FLAG_DECRYPTED) {
512 		if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
513 			return RX_DROP_UNUSABLE;
514 	} else {
515 		if (skb_linearize(rx->skb))
516 			return RX_DROP_UNUSABLE;
517 	}
518 
519 	if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
520 		ccmp_hdr2pn(pn, skb->data + hdrlen);
521 
522 		queue = rx->security_idx;
523 
524 		if (memcmp(pn, key->u.ccmp.rx_pn[queue],
525 			   IEEE80211_CCMP_PN_LEN) <= 0) {
526 			key->u.ccmp.replays++;
527 			return RX_DROP_UNUSABLE;
528 		}
529 
530 		if (!(status->flag & RX_FLAG_DECRYPTED)) {
531 			u8 aad[2 * AES_BLOCK_SIZE];
532 			u8 b_0[AES_BLOCK_SIZE];
533 			/* hardware didn't decrypt/verify MIC */
534 			ccmp_special_blocks(skb, pn, b_0, aad);
535 
536 			if (ieee80211_aes_ccm_decrypt(
537 				    key->u.ccmp.tfm, b_0, aad,
538 				    skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
539 				    data_len,
540 				    skb->data + skb->len - mic_len, mic_len))
541 				return RX_DROP_UNUSABLE;
542 		}
543 
544 		memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
545 	}
546 
547 	/* Remove CCMP header and MIC */
548 	if (pskb_trim(skb, skb->len - mic_len))
549 		return RX_DROP_UNUSABLE;
550 	memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
551 	skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
552 
553 	return RX_CONTINUE;
554 }
555 
556 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
557 {
558 	__le16 mask_fc;
559 	u8 qos_tid;
560 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
561 
562 	memcpy(j_0, hdr->addr2, ETH_ALEN);
563 	memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
564 	j_0[13] = 0;
565 	j_0[14] = 0;
566 	j_0[AES_BLOCK_SIZE - 1] = 0x01;
567 
568 	/* AAD (extra authenticate-only data) / masked 802.11 header
569 	 * FC | A1 | A2 | A3 | SC | [A4] | [QC]
570 	 */
571 	put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
572 	/* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
573 	 * Retry, PwrMgt, MoreData; set Protected
574 	 */
575 	mask_fc = hdr->frame_control;
576 	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
577 				IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
578 	if (!ieee80211_is_mgmt(hdr->frame_control))
579 		mask_fc &= ~cpu_to_le16(0x0070);
580 	mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
581 
582 	put_unaligned(mask_fc, (__le16 *)&aad[2]);
583 	memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
584 
585 	/* Mask Seq#, leave Frag# */
586 	aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
587 	aad[23] = 0;
588 
589 	if (ieee80211_is_data_qos(hdr->frame_control))
590 		qos_tid = *ieee80211_get_qos_ctl(hdr) &
591 			IEEE80211_QOS_CTL_TID_MASK;
592 	else
593 		qos_tid = 0;
594 
595 	if (ieee80211_has_a4(hdr->frame_control)) {
596 		memcpy(&aad[24], hdr->addr4, ETH_ALEN);
597 		aad[30] = qos_tid;
598 		aad[31] = 0;
599 	} else {
600 		memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
601 		aad[24] = qos_tid;
602 	}
603 }
604 
605 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
606 {
607 	hdr[0] = pn[5];
608 	hdr[1] = pn[4];
609 	hdr[2] = 0;
610 	hdr[3] = 0x20 | (key_id << 6);
611 	hdr[4] = pn[3];
612 	hdr[5] = pn[2];
613 	hdr[6] = pn[1];
614 	hdr[7] = pn[0];
615 }
616 
617 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
618 {
619 	pn[0] = hdr[7];
620 	pn[1] = hdr[6];
621 	pn[2] = hdr[5];
622 	pn[3] = hdr[4];
623 	pn[4] = hdr[1];
624 	pn[5] = hdr[0];
625 }
626 
627 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
628 {
629 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
630 	struct ieee80211_key *key = tx->key;
631 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
632 	int hdrlen, len, tail;
633 	u8 *pos;
634 	u8 pn[6];
635 	u64 pn64;
636 	u8 aad[2 * AES_BLOCK_SIZE];
637 	u8 j_0[AES_BLOCK_SIZE];
638 
639 	if (info->control.hw_key &&
640 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
641 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
642 	    !((info->control.hw_key->flags &
643 	       IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
644 	      ieee80211_is_mgmt(hdr->frame_control))) {
645 		/* hwaccel has no need for preallocated room for GCMP
646 		 * header or MIC fields
647 		 */
648 		return 0;
649 	}
650 
651 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
652 	len = skb->len - hdrlen;
653 
654 	if (info->control.hw_key)
655 		tail = 0;
656 	else
657 		tail = IEEE80211_GCMP_MIC_LEN;
658 
659 	if (WARN_ON(skb_tailroom(skb) < tail ||
660 		    skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
661 		return -1;
662 
663 	pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
664 	memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
665 	skb_set_network_header(skb, skb_network_offset(skb) +
666 				    IEEE80211_GCMP_HDR_LEN);
667 
668 	/* the HW only needs room for the IV, but not the actual IV */
669 	if (info->control.hw_key &&
670 	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
671 		return 0;
672 
673 	hdr = (struct ieee80211_hdr *)pos;
674 	pos += hdrlen;
675 
676 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
677 
678 	pn[5] = pn64;
679 	pn[4] = pn64 >> 8;
680 	pn[3] = pn64 >> 16;
681 	pn[2] = pn64 >> 24;
682 	pn[1] = pn64 >> 32;
683 	pn[0] = pn64 >> 40;
684 
685 	gcmp_pn2hdr(pos, pn, key->conf.keyidx);
686 
687 	/* hwaccel - with software GCMP header */
688 	if (info->control.hw_key)
689 		return 0;
690 
691 	pos += IEEE80211_GCMP_HDR_LEN;
692 	gcmp_special_blocks(skb, pn, j_0, aad);
693 	ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
694 				  skb_put(skb, IEEE80211_GCMP_MIC_LEN));
695 
696 	return 0;
697 }
698 
699 ieee80211_tx_result
700 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
701 {
702 	struct sk_buff *skb;
703 
704 	ieee80211_tx_set_protected(tx);
705 
706 	skb_queue_walk(&tx->skbs, skb) {
707 		if (gcmp_encrypt_skb(tx, skb) < 0)
708 			return TX_DROP;
709 	}
710 
711 	return TX_CONTINUE;
712 }
713 
714 ieee80211_rx_result
715 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
716 {
717 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
718 	int hdrlen;
719 	struct ieee80211_key *key = rx->key;
720 	struct sk_buff *skb = rx->skb;
721 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
722 	u8 pn[IEEE80211_GCMP_PN_LEN];
723 	int data_len;
724 	int queue;
725 
726 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
727 
728 	if (!ieee80211_is_data(hdr->frame_control) &&
729 	    !ieee80211_is_robust_mgmt_frame(skb))
730 		return RX_CONTINUE;
731 
732 	data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN -
733 		   IEEE80211_GCMP_MIC_LEN;
734 	if (!rx->sta || data_len < 0)
735 		return RX_DROP_UNUSABLE;
736 
737 	if (status->flag & RX_FLAG_DECRYPTED) {
738 		if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
739 			return RX_DROP_UNUSABLE;
740 	} else {
741 		if (skb_linearize(rx->skb))
742 			return RX_DROP_UNUSABLE;
743 	}
744 
745 	if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
746 		gcmp_hdr2pn(pn, skb->data + hdrlen);
747 
748 		queue = rx->security_idx;
749 
750 		if (memcmp(pn, key->u.gcmp.rx_pn[queue],
751 			   IEEE80211_GCMP_PN_LEN) <= 0) {
752 			key->u.gcmp.replays++;
753 			return RX_DROP_UNUSABLE;
754 		}
755 
756 		if (!(status->flag & RX_FLAG_DECRYPTED)) {
757 			u8 aad[2 * AES_BLOCK_SIZE];
758 			u8 j_0[AES_BLOCK_SIZE];
759 			/* hardware didn't decrypt/verify MIC */
760 			gcmp_special_blocks(skb, pn, j_0, aad);
761 
762 			if (ieee80211_aes_gcm_decrypt(
763 				    key->u.gcmp.tfm, j_0, aad,
764 				    skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
765 				    data_len,
766 				    skb->data + skb->len -
767 				    IEEE80211_GCMP_MIC_LEN))
768 				return RX_DROP_UNUSABLE;
769 		}
770 
771 		memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
772 	}
773 
774 	/* Remove GCMP header and MIC */
775 	if (pskb_trim(skb, skb->len - IEEE80211_GCMP_MIC_LEN))
776 		return RX_DROP_UNUSABLE;
777 	memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
778 	skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
779 
780 	return RX_CONTINUE;
781 }
782 
783 static ieee80211_tx_result
784 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
785 			    struct sk_buff *skb)
786 {
787 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
788 	struct ieee80211_key *key = tx->key;
789 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
790 	int hdrlen;
791 	u8 *pos, iv_len = key->conf.iv_len;
792 
793 	if (info->control.hw_key &&
794 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
795 		/* hwaccel has no need for preallocated head room */
796 		return TX_CONTINUE;
797 	}
798 
799 	if (unlikely(skb_headroom(skb) < iv_len &&
800 		     pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
801 		return TX_DROP;
802 
803 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
804 
805 	pos = skb_push(skb, iv_len);
806 	memmove(pos, pos + iv_len, hdrlen);
807 
808 	return TX_CONTINUE;
809 }
810 
811 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
812 {
813 	int i;
814 
815 	/* pn is little endian */
816 	for (i = len - 1; i >= 0; i--) {
817 		if (pn1[i] < pn2[i])
818 			return -1;
819 		else if (pn1[i] > pn2[i])
820 			return 1;
821 	}
822 
823 	return 0;
824 }
825 
826 static ieee80211_rx_result
827 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
828 {
829 	struct ieee80211_key *key = rx->key;
830 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
831 	const struct ieee80211_cipher_scheme *cs = NULL;
832 	int hdrlen = ieee80211_hdrlen(hdr->frame_control);
833 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
834 	int data_len;
835 	u8 *rx_pn;
836 	u8 *skb_pn;
837 	u8 qos_tid;
838 
839 	if (!rx->sta || !rx->sta->cipher_scheme ||
840 	    !(status->flag & RX_FLAG_DECRYPTED))
841 		return RX_DROP_UNUSABLE;
842 
843 	if (!ieee80211_is_data(hdr->frame_control))
844 		return RX_CONTINUE;
845 
846 	cs = rx->sta->cipher_scheme;
847 
848 	data_len = rx->skb->len - hdrlen - cs->hdr_len;
849 
850 	if (data_len < 0)
851 		return RX_DROP_UNUSABLE;
852 
853 	if (ieee80211_is_data_qos(hdr->frame_control))
854 		qos_tid = *ieee80211_get_qos_ctl(hdr) &
855 				IEEE80211_QOS_CTL_TID_MASK;
856 	else
857 		qos_tid = 0;
858 
859 	if (skb_linearize(rx->skb))
860 		return RX_DROP_UNUSABLE;
861 
862 	hdr = (struct ieee80211_hdr *)rx->skb->data;
863 
864 	rx_pn = key->u.gen.rx_pn[qos_tid];
865 	skb_pn = rx->skb->data + hdrlen + cs->pn_off;
866 
867 	if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
868 		return RX_DROP_UNUSABLE;
869 
870 	memcpy(rx_pn, skb_pn, cs->pn_len);
871 
872 	/* remove security header and MIC */
873 	if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
874 		return RX_DROP_UNUSABLE;
875 
876 	memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
877 	skb_pull(rx->skb, cs->hdr_len);
878 
879 	return RX_CONTINUE;
880 }
881 
882 static void bip_aad(struct sk_buff *skb, u8 *aad)
883 {
884 	__le16 mask_fc;
885 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
886 
887 	/* BIP AAD: FC(masked) || A1 || A2 || A3 */
888 
889 	/* FC type/subtype */
890 	/* Mask FC Retry, PwrMgt, MoreData flags to zero */
891 	mask_fc = hdr->frame_control;
892 	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
893 				IEEE80211_FCTL_MOREDATA);
894 	put_unaligned(mask_fc, (__le16 *) &aad[0]);
895 	/* A1 || A2 || A3 */
896 	memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
897 }
898 
899 
900 static inline void bip_ipn_set64(u8 *d, u64 pn)
901 {
902 	*d++ = pn;
903 	*d++ = pn >> 8;
904 	*d++ = pn >> 16;
905 	*d++ = pn >> 24;
906 	*d++ = pn >> 32;
907 	*d = pn >> 40;
908 }
909 
910 static inline void bip_ipn_swap(u8 *d, const u8 *s)
911 {
912 	*d++ = s[5];
913 	*d++ = s[4];
914 	*d++ = s[3];
915 	*d++ = s[2];
916 	*d++ = s[1];
917 	*d = s[0];
918 }
919 
920 
921 ieee80211_tx_result
922 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
923 {
924 	struct sk_buff *skb;
925 	struct ieee80211_tx_info *info;
926 	struct ieee80211_key *key = tx->key;
927 	struct ieee80211_mmie *mmie;
928 	u8 aad[20];
929 	u64 pn64;
930 
931 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
932 		return TX_DROP;
933 
934 	skb = skb_peek(&tx->skbs);
935 
936 	info = IEEE80211_SKB_CB(skb);
937 
938 	if (info->control.hw_key)
939 		return TX_CONTINUE;
940 
941 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
942 		return TX_DROP;
943 
944 	mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
945 	mmie->element_id = WLAN_EID_MMIE;
946 	mmie->length = sizeof(*mmie) - 2;
947 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
948 
949 	/* PN = PN + 1 */
950 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
951 
952 	bip_ipn_set64(mmie->sequence_number, pn64);
953 
954 	bip_aad(skb, aad);
955 
956 	/*
957 	 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
958 	 */
959 	ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
960 			   skb->data + 24, skb->len - 24, mmie->mic);
961 
962 	return TX_CONTINUE;
963 }
964 
965 ieee80211_tx_result
966 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
967 {
968 	struct sk_buff *skb;
969 	struct ieee80211_tx_info *info;
970 	struct ieee80211_key *key = tx->key;
971 	struct ieee80211_mmie_16 *mmie;
972 	u8 aad[20];
973 	u64 pn64;
974 
975 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
976 		return TX_DROP;
977 
978 	skb = skb_peek(&tx->skbs);
979 
980 	info = IEEE80211_SKB_CB(skb);
981 
982 	if (info->control.hw_key)
983 		return TX_CONTINUE;
984 
985 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
986 		return TX_DROP;
987 
988 	mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
989 	mmie->element_id = WLAN_EID_MMIE;
990 	mmie->length = sizeof(*mmie) - 2;
991 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
992 
993 	/* PN = PN + 1 */
994 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
995 
996 	bip_ipn_set64(mmie->sequence_number, pn64);
997 
998 	bip_aad(skb, aad);
999 
1000 	/* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1001 	 */
1002 	ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1003 			       skb->data + 24, skb->len - 24, mmie->mic);
1004 
1005 	return TX_CONTINUE;
1006 }
1007 
1008 ieee80211_rx_result
1009 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1010 {
1011 	struct sk_buff *skb = rx->skb;
1012 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1013 	struct ieee80211_key *key = rx->key;
1014 	struct ieee80211_mmie *mmie;
1015 	u8 aad[20], mic[8], ipn[6];
1016 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1017 
1018 	if (!ieee80211_is_mgmt(hdr->frame_control))
1019 		return RX_CONTINUE;
1020 
1021 	/* management frames are already linear */
1022 
1023 	if (skb->len < 24 + sizeof(*mmie))
1024 		return RX_DROP_UNUSABLE;
1025 
1026 	mmie = (struct ieee80211_mmie *)
1027 		(skb->data + skb->len - sizeof(*mmie));
1028 	if (mmie->element_id != WLAN_EID_MMIE ||
1029 	    mmie->length != sizeof(*mmie) - 2)
1030 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1031 
1032 	bip_ipn_swap(ipn, mmie->sequence_number);
1033 
1034 	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1035 		key->u.aes_cmac.replays++;
1036 		return RX_DROP_UNUSABLE;
1037 	}
1038 
1039 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1040 		/* hardware didn't decrypt/verify MIC */
1041 		bip_aad(skb, aad);
1042 		ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1043 				   skb->data + 24, skb->len - 24, mic);
1044 		if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1045 			key->u.aes_cmac.icverrors++;
1046 			return RX_DROP_UNUSABLE;
1047 		}
1048 	}
1049 
1050 	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1051 
1052 	/* Remove MMIE */
1053 	skb_trim(skb, skb->len - sizeof(*mmie));
1054 
1055 	return RX_CONTINUE;
1056 }
1057 
1058 ieee80211_rx_result
1059 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1060 {
1061 	struct sk_buff *skb = rx->skb;
1062 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1063 	struct ieee80211_key *key = rx->key;
1064 	struct ieee80211_mmie_16 *mmie;
1065 	u8 aad[20], mic[16], ipn[6];
1066 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1067 
1068 	if (!ieee80211_is_mgmt(hdr->frame_control))
1069 		return RX_CONTINUE;
1070 
1071 	/* management frames are already linear */
1072 
1073 	if (skb->len < 24 + sizeof(*mmie))
1074 		return RX_DROP_UNUSABLE;
1075 
1076 	mmie = (struct ieee80211_mmie_16 *)
1077 		(skb->data + skb->len - sizeof(*mmie));
1078 	if (mmie->element_id != WLAN_EID_MMIE ||
1079 	    mmie->length != sizeof(*mmie) - 2)
1080 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1081 
1082 	bip_ipn_swap(ipn, mmie->sequence_number);
1083 
1084 	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1085 		key->u.aes_cmac.replays++;
1086 		return RX_DROP_UNUSABLE;
1087 	}
1088 
1089 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1090 		/* hardware didn't decrypt/verify MIC */
1091 		bip_aad(skb, aad);
1092 		ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1093 				       skb->data + 24, skb->len - 24, mic);
1094 		if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1095 			key->u.aes_cmac.icverrors++;
1096 			return RX_DROP_UNUSABLE;
1097 		}
1098 	}
1099 
1100 	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1101 
1102 	/* Remove MMIE */
1103 	skb_trim(skb, skb->len - sizeof(*mmie));
1104 
1105 	return RX_CONTINUE;
1106 }
1107 
1108 ieee80211_tx_result
1109 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1110 {
1111 	struct sk_buff *skb;
1112 	struct ieee80211_tx_info *info;
1113 	struct ieee80211_key *key = tx->key;
1114 	struct ieee80211_mmie_16 *mmie;
1115 	struct ieee80211_hdr *hdr;
1116 	u8 aad[20];
1117 	u64 pn64;
1118 	u8 nonce[12];
1119 
1120 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1121 		return TX_DROP;
1122 
1123 	skb = skb_peek(&tx->skbs);
1124 
1125 	info = IEEE80211_SKB_CB(skb);
1126 
1127 	if (info->control.hw_key)
1128 		return TX_CONTINUE;
1129 
1130 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1131 		return TX_DROP;
1132 
1133 	mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
1134 	mmie->element_id = WLAN_EID_MMIE;
1135 	mmie->length = sizeof(*mmie) - 2;
1136 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
1137 
1138 	/* PN = PN + 1 */
1139 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
1140 
1141 	bip_ipn_set64(mmie->sequence_number, pn64);
1142 
1143 	bip_aad(skb, aad);
1144 
1145 	hdr = (struct ieee80211_hdr *)skb->data;
1146 	memcpy(nonce, hdr->addr2, ETH_ALEN);
1147 	bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1148 
1149 	/* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1150 	if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1151 			       skb->data + 24, skb->len - 24, mmie->mic) < 0)
1152 		return TX_DROP;
1153 
1154 	return TX_CONTINUE;
1155 }
1156 
1157 ieee80211_rx_result
1158 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1159 {
1160 	struct sk_buff *skb = rx->skb;
1161 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1162 	struct ieee80211_key *key = rx->key;
1163 	struct ieee80211_mmie_16 *mmie;
1164 	u8 aad[20], mic[16], ipn[6], nonce[12];
1165 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1166 
1167 	if (!ieee80211_is_mgmt(hdr->frame_control))
1168 		return RX_CONTINUE;
1169 
1170 	/* management frames are already linear */
1171 
1172 	if (skb->len < 24 + sizeof(*mmie))
1173 		return RX_DROP_UNUSABLE;
1174 
1175 	mmie = (struct ieee80211_mmie_16 *)
1176 		(skb->data + skb->len - sizeof(*mmie));
1177 	if (mmie->element_id != WLAN_EID_MMIE ||
1178 	    mmie->length != sizeof(*mmie) - 2)
1179 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1180 
1181 	bip_ipn_swap(ipn, mmie->sequence_number);
1182 
1183 	if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1184 		key->u.aes_gmac.replays++;
1185 		return RX_DROP_UNUSABLE;
1186 	}
1187 
1188 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1189 		/* hardware didn't decrypt/verify MIC */
1190 		bip_aad(skb, aad);
1191 
1192 		memcpy(nonce, hdr->addr2, ETH_ALEN);
1193 		memcpy(nonce + ETH_ALEN, ipn, 6);
1194 
1195 		if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1196 				       skb->data + 24, skb->len - 24,
1197 				       mic) < 0 ||
1198 		    memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1199 			key->u.aes_gmac.icverrors++;
1200 			return RX_DROP_UNUSABLE;
1201 		}
1202 	}
1203 
1204 	memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1205 
1206 	/* Remove MMIE */
1207 	skb_trim(skb, skb->len - sizeof(*mmie));
1208 
1209 	return RX_CONTINUE;
1210 }
1211 
1212 ieee80211_tx_result
1213 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1214 {
1215 	struct sk_buff *skb;
1216 	struct ieee80211_tx_info *info = NULL;
1217 	ieee80211_tx_result res;
1218 
1219 	skb_queue_walk(&tx->skbs, skb) {
1220 		info  = IEEE80211_SKB_CB(skb);
1221 
1222 		/* handle hw-only algorithm */
1223 		if (!info->control.hw_key)
1224 			return TX_DROP;
1225 
1226 		if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1227 			res = ieee80211_crypto_cs_encrypt(tx, skb);
1228 			if (res != TX_CONTINUE)
1229 				return res;
1230 		}
1231 	}
1232 
1233 	ieee80211_tx_set_protected(tx);
1234 
1235 	return TX_CONTINUE;
1236 }
1237 
1238 ieee80211_rx_result
1239 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1240 {
1241 	if (rx->sta && rx->sta->cipher_scheme)
1242 		return ieee80211_crypto_cs_decrypt(rx);
1243 
1244 	return RX_DROP_UNUSABLE;
1245 }
1246