xref: /linux/net/mac80211/wpa.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
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->u.ccmp.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 	ccmp_hdr2pn(pn, skb->data + hdrlen);
520 
521 	queue = rx->security_idx;
522 
523 	if (memcmp(pn, key->u.ccmp.rx_pn[queue], IEEE80211_CCMP_PN_LEN) <= 0) {
524 		key->u.ccmp.replays++;
525 		return RX_DROP_UNUSABLE;
526 	}
527 
528 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
529 		u8 aad[2 * AES_BLOCK_SIZE];
530 		u8 b_0[AES_BLOCK_SIZE];
531 		/* hardware didn't decrypt/verify MIC */
532 		ccmp_special_blocks(skb, pn, b_0, aad);
533 
534 		if (ieee80211_aes_ccm_decrypt(
535 			    key->u.ccmp.tfm, b_0, aad,
536 			    skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
537 			    data_len,
538 			    skb->data + skb->len - mic_len, mic_len))
539 			return RX_DROP_UNUSABLE;
540 	}
541 
542 	memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
543 
544 	/* Remove CCMP header and MIC */
545 	if (pskb_trim(skb, skb->len - mic_len))
546 		return RX_DROP_UNUSABLE;
547 	memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
548 	skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
549 
550 	return RX_CONTINUE;
551 }
552 
553 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
554 {
555 	__le16 mask_fc;
556 	u8 qos_tid;
557 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
558 
559 	memcpy(j_0, hdr->addr2, ETH_ALEN);
560 	memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
561 	j_0[13] = 0;
562 	j_0[14] = 0;
563 	j_0[AES_BLOCK_SIZE - 1] = 0x01;
564 
565 	/* AAD (extra authenticate-only data) / masked 802.11 header
566 	 * FC | A1 | A2 | A3 | SC | [A4] | [QC]
567 	 */
568 	put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
569 	/* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
570 	 * Retry, PwrMgt, MoreData; set Protected
571 	 */
572 	mask_fc = hdr->frame_control;
573 	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
574 				IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
575 	if (!ieee80211_is_mgmt(hdr->frame_control))
576 		mask_fc &= ~cpu_to_le16(0x0070);
577 	mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
578 
579 	put_unaligned(mask_fc, (__le16 *)&aad[2]);
580 	memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
581 
582 	/* Mask Seq#, leave Frag# */
583 	aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
584 	aad[23] = 0;
585 
586 	if (ieee80211_is_data_qos(hdr->frame_control))
587 		qos_tid = *ieee80211_get_qos_ctl(hdr) &
588 			IEEE80211_QOS_CTL_TID_MASK;
589 	else
590 		qos_tid = 0;
591 
592 	if (ieee80211_has_a4(hdr->frame_control)) {
593 		memcpy(&aad[24], hdr->addr4, ETH_ALEN);
594 		aad[30] = qos_tid;
595 		aad[31] = 0;
596 	} else {
597 		memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
598 		aad[24] = qos_tid;
599 	}
600 }
601 
602 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
603 {
604 	hdr[0] = pn[5];
605 	hdr[1] = pn[4];
606 	hdr[2] = 0;
607 	hdr[3] = 0x20 | (key_id << 6);
608 	hdr[4] = pn[3];
609 	hdr[5] = pn[2];
610 	hdr[6] = pn[1];
611 	hdr[7] = pn[0];
612 }
613 
614 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
615 {
616 	pn[0] = hdr[7];
617 	pn[1] = hdr[6];
618 	pn[2] = hdr[5];
619 	pn[3] = hdr[4];
620 	pn[4] = hdr[1];
621 	pn[5] = hdr[0];
622 }
623 
624 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
625 {
626 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
627 	struct ieee80211_key *key = tx->key;
628 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
629 	int hdrlen, len, tail;
630 	u8 *pos;
631 	u8 pn[6];
632 	u64 pn64;
633 	u8 aad[2 * AES_BLOCK_SIZE];
634 	u8 j_0[AES_BLOCK_SIZE];
635 
636 	if (info->control.hw_key &&
637 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
638 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
639 	    !((info->control.hw_key->flags &
640 	       IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
641 	      ieee80211_is_mgmt(hdr->frame_control))) {
642 		/* hwaccel has no need for preallocated room for GCMP
643 		 * header or MIC fields
644 		 */
645 		return 0;
646 	}
647 
648 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
649 	len = skb->len - hdrlen;
650 
651 	if (info->control.hw_key)
652 		tail = 0;
653 	else
654 		tail = IEEE80211_GCMP_MIC_LEN;
655 
656 	if (WARN_ON(skb_tailroom(skb) < tail ||
657 		    skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
658 		return -1;
659 
660 	pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
661 	memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
662 	skb_set_network_header(skb, skb_network_offset(skb) +
663 				    IEEE80211_GCMP_HDR_LEN);
664 
665 	/* the HW only needs room for the IV, but not the actual IV */
666 	if (info->control.hw_key &&
667 	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
668 		return 0;
669 
670 	hdr = (struct ieee80211_hdr *)pos;
671 	pos += hdrlen;
672 
673 	pn64 = atomic64_inc_return(&key->u.gcmp.tx_pn);
674 
675 	pn[5] = pn64;
676 	pn[4] = pn64 >> 8;
677 	pn[3] = pn64 >> 16;
678 	pn[2] = pn64 >> 24;
679 	pn[1] = pn64 >> 32;
680 	pn[0] = pn64 >> 40;
681 
682 	gcmp_pn2hdr(pos, pn, key->conf.keyidx);
683 
684 	/* hwaccel - with software GCMP header */
685 	if (info->control.hw_key)
686 		return 0;
687 
688 	pos += IEEE80211_GCMP_HDR_LEN;
689 	gcmp_special_blocks(skb, pn, j_0, aad);
690 	ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
691 				  skb_put(skb, IEEE80211_GCMP_MIC_LEN));
692 
693 	return 0;
694 }
695 
696 ieee80211_tx_result
697 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
698 {
699 	struct sk_buff *skb;
700 
701 	ieee80211_tx_set_protected(tx);
702 
703 	skb_queue_walk(&tx->skbs, skb) {
704 		if (gcmp_encrypt_skb(tx, skb) < 0)
705 			return TX_DROP;
706 	}
707 
708 	return TX_CONTINUE;
709 }
710 
711 ieee80211_rx_result
712 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
713 {
714 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
715 	int hdrlen;
716 	struct ieee80211_key *key = rx->key;
717 	struct sk_buff *skb = rx->skb;
718 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
719 	u8 pn[IEEE80211_GCMP_PN_LEN];
720 	int data_len;
721 	int queue;
722 
723 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
724 
725 	if (!ieee80211_is_data(hdr->frame_control) &&
726 	    !ieee80211_is_robust_mgmt_frame(skb))
727 		return RX_CONTINUE;
728 
729 	data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN -
730 		   IEEE80211_GCMP_MIC_LEN;
731 	if (!rx->sta || data_len < 0)
732 		return RX_DROP_UNUSABLE;
733 
734 	if (status->flag & RX_FLAG_DECRYPTED) {
735 		if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
736 			return RX_DROP_UNUSABLE;
737 	} else {
738 		if (skb_linearize(rx->skb))
739 			return RX_DROP_UNUSABLE;
740 	}
741 
742 	gcmp_hdr2pn(pn, skb->data + hdrlen);
743 
744 	queue = rx->security_idx;
745 
746 	if (memcmp(pn, key->u.gcmp.rx_pn[queue], IEEE80211_GCMP_PN_LEN) <= 0) {
747 		key->u.gcmp.replays++;
748 		return RX_DROP_UNUSABLE;
749 	}
750 
751 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
752 		u8 aad[2 * AES_BLOCK_SIZE];
753 		u8 j_0[AES_BLOCK_SIZE];
754 		/* hardware didn't decrypt/verify MIC */
755 		gcmp_special_blocks(skb, pn, j_0, aad);
756 
757 		if (ieee80211_aes_gcm_decrypt(
758 			    key->u.gcmp.tfm, j_0, aad,
759 			    skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
760 			    data_len,
761 			    skb->data + skb->len - IEEE80211_GCMP_MIC_LEN))
762 			return RX_DROP_UNUSABLE;
763 	}
764 
765 	memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
766 
767 	/* Remove GCMP header and MIC */
768 	if (pskb_trim(skb, skb->len - IEEE80211_GCMP_MIC_LEN))
769 		return RX_DROP_UNUSABLE;
770 	memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
771 	skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
772 
773 	return RX_CONTINUE;
774 }
775 
776 static ieee80211_tx_result
777 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
778 			    struct sk_buff *skb)
779 {
780 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
781 	struct ieee80211_key *key = tx->key;
782 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
783 	const struct ieee80211_cipher_scheme *cs = key->sta->cipher_scheme;
784 	int hdrlen;
785 	u8 *pos;
786 
787 	if (info->control.hw_key &&
788 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
789 		/* hwaccel has no need for preallocated head room */
790 		return TX_CONTINUE;
791 	}
792 
793 	if (unlikely(skb_headroom(skb) < cs->hdr_len &&
794 		     pskb_expand_head(skb, cs->hdr_len, 0, GFP_ATOMIC)))
795 		return TX_DROP;
796 
797 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
798 
799 	pos = skb_push(skb, cs->hdr_len);
800 	memmove(pos, pos + cs->hdr_len, hdrlen);
801 
802 	return TX_CONTINUE;
803 }
804 
805 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
806 {
807 	int i;
808 
809 	/* pn is little endian */
810 	for (i = len - 1; i >= 0; i--) {
811 		if (pn1[i] < pn2[i])
812 			return -1;
813 		else if (pn1[i] > pn2[i])
814 			return 1;
815 	}
816 
817 	return 0;
818 }
819 
820 static ieee80211_rx_result
821 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
822 {
823 	struct ieee80211_key *key = rx->key;
824 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
825 	const struct ieee80211_cipher_scheme *cs = NULL;
826 	int hdrlen = ieee80211_hdrlen(hdr->frame_control);
827 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
828 	int data_len;
829 	u8 *rx_pn;
830 	u8 *skb_pn;
831 	u8 qos_tid;
832 
833 	if (!rx->sta || !rx->sta->cipher_scheme ||
834 	    !(status->flag & RX_FLAG_DECRYPTED))
835 		return RX_DROP_UNUSABLE;
836 
837 	if (!ieee80211_is_data(hdr->frame_control))
838 		return RX_CONTINUE;
839 
840 	cs = rx->sta->cipher_scheme;
841 
842 	data_len = rx->skb->len - hdrlen - cs->hdr_len;
843 
844 	if (data_len < 0)
845 		return RX_DROP_UNUSABLE;
846 
847 	if (ieee80211_is_data_qos(hdr->frame_control))
848 		qos_tid = *ieee80211_get_qos_ctl(hdr) &
849 				IEEE80211_QOS_CTL_TID_MASK;
850 	else
851 		qos_tid = 0;
852 
853 	if (skb_linearize(rx->skb))
854 		return RX_DROP_UNUSABLE;
855 
856 	hdr = (struct ieee80211_hdr *)rx->skb->data;
857 
858 	rx_pn = key->u.gen.rx_pn[qos_tid];
859 	skb_pn = rx->skb->data + hdrlen + cs->pn_off;
860 
861 	if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
862 		return RX_DROP_UNUSABLE;
863 
864 	memcpy(rx_pn, skb_pn, cs->pn_len);
865 
866 	/* remove security header and MIC */
867 	if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
868 		return RX_DROP_UNUSABLE;
869 
870 	memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
871 	skb_pull(rx->skb, cs->hdr_len);
872 
873 	return RX_CONTINUE;
874 }
875 
876 static void bip_aad(struct sk_buff *skb, u8 *aad)
877 {
878 	__le16 mask_fc;
879 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
880 
881 	/* BIP AAD: FC(masked) || A1 || A2 || A3 */
882 
883 	/* FC type/subtype */
884 	/* Mask FC Retry, PwrMgt, MoreData flags to zero */
885 	mask_fc = hdr->frame_control;
886 	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
887 				IEEE80211_FCTL_MOREDATA);
888 	put_unaligned(mask_fc, (__le16 *) &aad[0]);
889 	/* A1 || A2 || A3 */
890 	memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
891 }
892 
893 
894 static inline void bip_ipn_set64(u8 *d, u64 pn)
895 {
896 	*d++ = pn;
897 	*d++ = pn >> 8;
898 	*d++ = pn >> 16;
899 	*d++ = pn >> 24;
900 	*d++ = pn >> 32;
901 	*d = pn >> 40;
902 }
903 
904 static inline void bip_ipn_swap(u8 *d, const u8 *s)
905 {
906 	*d++ = s[5];
907 	*d++ = s[4];
908 	*d++ = s[3];
909 	*d++ = s[2];
910 	*d++ = s[1];
911 	*d = s[0];
912 }
913 
914 
915 ieee80211_tx_result
916 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
917 {
918 	struct sk_buff *skb;
919 	struct ieee80211_tx_info *info;
920 	struct ieee80211_key *key = tx->key;
921 	struct ieee80211_mmie *mmie;
922 	u8 aad[20];
923 	u64 pn64;
924 
925 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
926 		return TX_DROP;
927 
928 	skb = skb_peek(&tx->skbs);
929 
930 	info = IEEE80211_SKB_CB(skb);
931 
932 	if (info->control.hw_key)
933 		return TX_CONTINUE;
934 
935 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
936 		return TX_DROP;
937 
938 	mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
939 	mmie->element_id = WLAN_EID_MMIE;
940 	mmie->length = sizeof(*mmie) - 2;
941 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
942 
943 	/* PN = PN + 1 */
944 	pn64 = atomic64_inc_return(&key->u.aes_cmac.tx_pn);
945 
946 	bip_ipn_set64(mmie->sequence_number, pn64);
947 
948 	bip_aad(skb, aad);
949 
950 	/*
951 	 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
952 	 */
953 	ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
954 			   skb->data + 24, skb->len - 24, mmie->mic);
955 
956 	return TX_CONTINUE;
957 }
958 
959 ieee80211_tx_result
960 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
961 {
962 	struct sk_buff *skb;
963 	struct ieee80211_tx_info *info;
964 	struct ieee80211_key *key = tx->key;
965 	struct ieee80211_mmie_16 *mmie;
966 	u8 aad[20];
967 	u64 pn64;
968 
969 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
970 		return TX_DROP;
971 
972 	skb = skb_peek(&tx->skbs);
973 
974 	info = IEEE80211_SKB_CB(skb);
975 
976 	if (info->control.hw_key)
977 		return TX_CONTINUE;
978 
979 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
980 		return TX_DROP;
981 
982 	mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
983 	mmie->element_id = WLAN_EID_MMIE;
984 	mmie->length = sizeof(*mmie) - 2;
985 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
986 
987 	/* PN = PN + 1 */
988 	pn64 = atomic64_inc_return(&key->u.aes_cmac.tx_pn);
989 
990 	bip_ipn_set64(mmie->sequence_number, pn64);
991 
992 	bip_aad(skb, aad);
993 
994 	/* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
995 	 */
996 	ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
997 			       skb->data + 24, skb->len - 24, mmie->mic);
998 
999 	return TX_CONTINUE;
1000 }
1001 
1002 ieee80211_rx_result
1003 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1004 {
1005 	struct sk_buff *skb = rx->skb;
1006 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1007 	struct ieee80211_key *key = rx->key;
1008 	struct ieee80211_mmie *mmie;
1009 	u8 aad[20], mic[8], ipn[6];
1010 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1011 
1012 	if (!ieee80211_is_mgmt(hdr->frame_control))
1013 		return RX_CONTINUE;
1014 
1015 	/* management frames are already linear */
1016 
1017 	if (skb->len < 24 + sizeof(*mmie))
1018 		return RX_DROP_UNUSABLE;
1019 
1020 	mmie = (struct ieee80211_mmie *)
1021 		(skb->data + skb->len - sizeof(*mmie));
1022 	if (mmie->element_id != WLAN_EID_MMIE ||
1023 	    mmie->length != sizeof(*mmie) - 2)
1024 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1025 
1026 	bip_ipn_swap(ipn, mmie->sequence_number);
1027 
1028 	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1029 		key->u.aes_cmac.replays++;
1030 		return RX_DROP_UNUSABLE;
1031 	}
1032 
1033 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1034 		/* hardware didn't decrypt/verify MIC */
1035 		bip_aad(skb, aad);
1036 		ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1037 				   skb->data + 24, skb->len - 24, mic);
1038 		if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1039 			key->u.aes_cmac.icverrors++;
1040 			return RX_DROP_UNUSABLE;
1041 		}
1042 	}
1043 
1044 	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1045 
1046 	/* Remove MMIE */
1047 	skb_trim(skb, skb->len - sizeof(*mmie));
1048 
1049 	return RX_CONTINUE;
1050 }
1051 
1052 ieee80211_rx_result
1053 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1054 {
1055 	struct sk_buff *skb = rx->skb;
1056 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1057 	struct ieee80211_key *key = rx->key;
1058 	struct ieee80211_mmie_16 *mmie;
1059 	u8 aad[20], mic[16], ipn[6];
1060 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1061 
1062 	if (!ieee80211_is_mgmt(hdr->frame_control))
1063 		return RX_CONTINUE;
1064 
1065 	/* management frames are already linear */
1066 
1067 	if (skb->len < 24 + sizeof(*mmie))
1068 		return RX_DROP_UNUSABLE;
1069 
1070 	mmie = (struct ieee80211_mmie_16 *)
1071 		(skb->data + skb->len - sizeof(*mmie));
1072 	if (mmie->element_id != WLAN_EID_MMIE ||
1073 	    mmie->length != sizeof(*mmie) - 2)
1074 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1075 
1076 	bip_ipn_swap(ipn, mmie->sequence_number);
1077 
1078 	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1079 		key->u.aes_cmac.replays++;
1080 		return RX_DROP_UNUSABLE;
1081 	}
1082 
1083 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1084 		/* hardware didn't decrypt/verify MIC */
1085 		bip_aad(skb, aad);
1086 		ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1087 				       skb->data + 24, skb->len - 24, mic);
1088 		if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1089 			key->u.aes_cmac.icverrors++;
1090 			return RX_DROP_UNUSABLE;
1091 		}
1092 	}
1093 
1094 	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1095 
1096 	/* Remove MMIE */
1097 	skb_trim(skb, skb->len - sizeof(*mmie));
1098 
1099 	return RX_CONTINUE;
1100 }
1101 
1102 ieee80211_tx_result
1103 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1104 {
1105 	struct sk_buff *skb;
1106 	struct ieee80211_tx_info *info;
1107 	struct ieee80211_key *key = tx->key;
1108 	struct ieee80211_mmie_16 *mmie;
1109 	struct ieee80211_hdr *hdr;
1110 	u8 aad[20];
1111 	u64 pn64;
1112 	u8 nonce[12];
1113 
1114 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1115 		return TX_DROP;
1116 
1117 	skb = skb_peek(&tx->skbs);
1118 
1119 	info = IEEE80211_SKB_CB(skb);
1120 
1121 	if (info->control.hw_key)
1122 		return TX_CONTINUE;
1123 
1124 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1125 		return TX_DROP;
1126 
1127 	mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
1128 	mmie->element_id = WLAN_EID_MMIE;
1129 	mmie->length = sizeof(*mmie) - 2;
1130 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
1131 
1132 	/* PN = PN + 1 */
1133 	pn64 = atomic64_inc_return(&key->u.aes_gmac.tx_pn);
1134 
1135 	bip_ipn_set64(mmie->sequence_number, pn64);
1136 
1137 	bip_aad(skb, aad);
1138 
1139 	hdr = (struct ieee80211_hdr *)skb->data;
1140 	memcpy(nonce, hdr->addr2, ETH_ALEN);
1141 	bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1142 
1143 	/* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1144 	if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1145 			       skb->data + 24, skb->len - 24, mmie->mic) < 0)
1146 		return TX_DROP;
1147 
1148 	return TX_CONTINUE;
1149 }
1150 
1151 ieee80211_rx_result
1152 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1153 {
1154 	struct sk_buff *skb = rx->skb;
1155 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1156 	struct ieee80211_key *key = rx->key;
1157 	struct ieee80211_mmie_16 *mmie;
1158 	u8 aad[20], mic[16], ipn[6], nonce[12];
1159 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1160 
1161 	if (!ieee80211_is_mgmt(hdr->frame_control))
1162 		return RX_CONTINUE;
1163 
1164 	/* management frames are already linear */
1165 
1166 	if (skb->len < 24 + sizeof(*mmie))
1167 		return RX_DROP_UNUSABLE;
1168 
1169 	mmie = (struct ieee80211_mmie_16 *)
1170 		(skb->data + skb->len - sizeof(*mmie));
1171 	if (mmie->element_id != WLAN_EID_MMIE ||
1172 	    mmie->length != sizeof(*mmie) - 2)
1173 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1174 
1175 	bip_ipn_swap(ipn, mmie->sequence_number);
1176 
1177 	if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1178 		key->u.aes_gmac.replays++;
1179 		return RX_DROP_UNUSABLE;
1180 	}
1181 
1182 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1183 		/* hardware didn't decrypt/verify MIC */
1184 		bip_aad(skb, aad);
1185 
1186 		memcpy(nonce, hdr->addr2, ETH_ALEN);
1187 		memcpy(nonce + ETH_ALEN, ipn, 6);
1188 
1189 		if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1190 				       skb->data + 24, skb->len - 24,
1191 				       mic) < 0 ||
1192 		    memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1193 			key->u.aes_gmac.icverrors++;
1194 			return RX_DROP_UNUSABLE;
1195 		}
1196 	}
1197 
1198 	memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1199 
1200 	/* Remove MMIE */
1201 	skb_trim(skb, skb->len - sizeof(*mmie));
1202 
1203 	return RX_CONTINUE;
1204 }
1205 
1206 ieee80211_tx_result
1207 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1208 {
1209 	struct sk_buff *skb;
1210 	struct ieee80211_tx_info *info = NULL;
1211 	ieee80211_tx_result res;
1212 
1213 	skb_queue_walk(&tx->skbs, skb) {
1214 		info  = IEEE80211_SKB_CB(skb);
1215 
1216 		/* handle hw-only algorithm */
1217 		if (!info->control.hw_key)
1218 			return TX_DROP;
1219 
1220 		if (tx->key->sta->cipher_scheme) {
1221 			res = ieee80211_crypto_cs_encrypt(tx, skb);
1222 			if (res != TX_CONTINUE)
1223 				return res;
1224 		}
1225 	}
1226 
1227 	ieee80211_tx_set_protected(tx);
1228 
1229 	return TX_CONTINUE;
1230 }
1231 
1232 ieee80211_rx_result
1233 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1234 {
1235 	if (rx->sta && rx->sta->cipher_scheme)
1236 		return ieee80211_crypto_cs_decrypt(rx);
1237 
1238 	return RX_DROP_UNUSABLE;
1239 }
1240