xref: /openbmc/linux/net/mac80211/wpa.c (revision 9dbbc3b9)
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 	hdr = (struct ieee80211_hdr *) pos;
453 	pos += hdrlen;
454 
455 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
456 
457 	pn[5] = pn64;
458 	pn[4] = pn64 >> 8;
459 	pn[3] = pn64 >> 16;
460 	pn[2] = pn64 >> 24;
461 	pn[1] = pn64 >> 32;
462 	pn[0] = pn64 >> 40;
463 
464 	ccmp_pn2hdr(pos, pn, key->conf.keyidx);
465 
466 	/* hwaccel - with software CCMP header */
467 	if (info->control.hw_key)
468 		return 0;
469 
470 	pos += IEEE80211_CCMP_HDR_LEN;
471 	ccmp_special_blocks(skb, pn, b_0, aad);
472 	return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
473 					 skb_put(skb, mic_len));
474 }
475 
476 
477 ieee80211_tx_result
478 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx,
479 			      unsigned int mic_len)
480 {
481 	struct sk_buff *skb;
482 
483 	ieee80211_tx_set_protected(tx);
484 
485 	skb_queue_walk(&tx->skbs, skb) {
486 		if (ccmp_encrypt_skb(tx, skb, mic_len) < 0)
487 			return TX_DROP;
488 	}
489 
490 	return TX_CONTINUE;
491 }
492 
493 
494 ieee80211_rx_result
495 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
496 			      unsigned int mic_len)
497 {
498 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
499 	int hdrlen;
500 	struct ieee80211_key *key = rx->key;
501 	struct sk_buff *skb = rx->skb;
502 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
503 	u8 pn[IEEE80211_CCMP_PN_LEN];
504 	int data_len;
505 	int queue;
506 
507 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
508 
509 	if (!ieee80211_is_data(hdr->frame_control) &&
510 	    !ieee80211_is_robust_mgmt_frame(skb))
511 		return RX_CONTINUE;
512 
513 	if (status->flag & RX_FLAG_DECRYPTED) {
514 		if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
515 			return RX_DROP_UNUSABLE;
516 		if (status->flag & RX_FLAG_MIC_STRIPPED)
517 			mic_len = 0;
518 	} else {
519 		if (skb_linearize(rx->skb))
520 			return RX_DROP_UNUSABLE;
521 	}
522 
523 	data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
524 	if (!rx->sta || data_len < 0)
525 		return RX_DROP_UNUSABLE;
526 
527 	if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
528 		int res;
529 
530 		ccmp_hdr2pn(pn, skb->data + hdrlen);
531 
532 		queue = rx->security_idx;
533 
534 		res = memcmp(pn, key->u.ccmp.rx_pn[queue],
535 			     IEEE80211_CCMP_PN_LEN);
536 		if (res < 0 ||
537 		    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
538 			key->u.ccmp.replays++;
539 			return RX_DROP_UNUSABLE;
540 		}
541 
542 		if (!(status->flag & RX_FLAG_DECRYPTED)) {
543 			u8 aad[2 * AES_BLOCK_SIZE];
544 			u8 b_0[AES_BLOCK_SIZE];
545 			/* hardware didn't decrypt/verify MIC */
546 			ccmp_special_blocks(skb, pn, b_0, aad);
547 
548 			if (ieee80211_aes_ccm_decrypt(
549 				    key->u.ccmp.tfm, b_0, aad,
550 				    skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
551 				    data_len,
552 				    skb->data + skb->len - mic_len))
553 				return RX_DROP_UNUSABLE;
554 		}
555 
556 		memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
557 		if (unlikely(ieee80211_is_frag(hdr)))
558 			memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN);
559 	}
560 
561 	/* Remove CCMP header and MIC */
562 	if (pskb_trim(skb, skb->len - mic_len))
563 		return RX_DROP_UNUSABLE;
564 	memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
565 	skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
566 
567 	return RX_CONTINUE;
568 }
569 
570 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
571 {
572 	__le16 mask_fc;
573 	u8 qos_tid;
574 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
575 
576 	memcpy(j_0, hdr->addr2, ETH_ALEN);
577 	memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
578 	j_0[13] = 0;
579 	j_0[14] = 0;
580 	j_0[AES_BLOCK_SIZE - 1] = 0x01;
581 
582 	/* AAD (extra authenticate-only data) / masked 802.11 header
583 	 * FC | A1 | A2 | A3 | SC | [A4] | [QC]
584 	 */
585 	put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
586 	/* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
587 	 * Retry, PwrMgt, MoreData; set Protected
588 	 */
589 	mask_fc = hdr->frame_control;
590 	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
591 				IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
592 	if (!ieee80211_is_mgmt(hdr->frame_control))
593 		mask_fc &= ~cpu_to_le16(0x0070);
594 	mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
595 
596 	put_unaligned(mask_fc, (__le16 *)&aad[2]);
597 	memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
598 
599 	/* Mask Seq#, leave Frag# */
600 	aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
601 	aad[23] = 0;
602 
603 	if (ieee80211_is_data_qos(hdr->frame_control))
604 		qos_tid = ieee80211_get_tid(hdr);
605 	else
606 		qos_tid = 0;
607 
608 	if (ieee80211_has_a4(hdr->frame_control)) {
609 		memcpy(&aad[24], hdr->addr4, ETH_ALEN);
610 		aad[30] = qos_tid;
611 		aad[31] = 0;
612 	} else {
613 		memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
614 		aad[24] = qos_tid;
615 	}
616 }
617 
618 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
619 {
620 	hdr[0] = pn[5];
621 	hdr[1] = pn[4];
622 	hdr[2] = 0;
623 	hdr[3] = 0x20 | (key_id << 6);
624 	hdr[4] = pn[3];
625 	hdr[5] = pn[2];
626 	hdr[6] = pn[1];
627 	hdr[7] = pn[0];
628 }
629 
630 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
631 {
632 	pn[0] = hdr[7];
633 	pn[1] = hdr[6];
634 	pn[2] = hdr[5];
635 	pn[3] = hdr[4];
636 	pn[4] = hdr[1];
637 	pn[5] = hdr[0];
638 }
639 
640 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
641 {
642 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
643 	struct ieee80211_key *key = tx->key;
644 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
645 	int hdrlen, len, tail;
646 	u8 *pos;
647 	u8 pn[6];
648 	u64 pn64;
649 	u8 aad[GCM_AAD_LEN];
650 	u8 j_0[AES_BLOCK_SIZE];
651 
652 	if (info->control.hw_key &&
653 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
654 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
655 	    !((info->control.hw_key->flags &
656 	       IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
657 	      ieee80211_is_mgmt(hdr->frame_control))) {
658 		/* hwaccel has no need for preallocated room for GCMP
659 		 * header or MIC fields
660 		 */
661 		return 0;
662 	}
663 
664 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
665 	len = skb->len - hdrlen;
666 
667 	if (info->control.hw_key)
668 		tail = 0;
669 	else
670 		tail = IEEE80211_GCMP_MIC_LEN;
671 
672 	if (WARN_ON(skb_tailroom(skb) < tail ||
673 		    skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
674 		return -1;
675 
676 	pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
677 	memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
678 	skb_set_network_header(skb, skb_network_offset(skb) +
679 				    IEEE80211_GCMP_HDR_LEN);
680 
681 	/* the HW only needs room for the IV, but not the actual IV */
682 	if (info->control.hw_key &&
683 	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
684 		return 0;
685 
686 	hdr = (struct ieee80211_hdr *)pos;
687 	pos += hdrlen;
688 
689 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
690 
691 	pn[5] = pn64;
692 	pn[4] = pn64 >> 8;
693 	pn[3] = pn64 >> 16;
694 	pn[2] = pn64 >> 24;
695 	pn[1] = pn64 >> 32;
696 	pn[0] = pn64 >> 40;
697 
698 	gcmp_pn2hdr(pos, pn, key->conf.keyidx);
699 
700 	/* hwaccel - with software GCMP header */
701 	if (info->control.hw_key)
702 		return 0;
703 
704 	pos += IEEE80211_GCMP_HDR_LEN;
705 	gcmp_special_blocks(skb, pn, j_0, aad);
706 	return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
707 					 skb_put(skb, IEEE80211_GCMP_MIC_LEN));
708 }
709 
710 ieee80211_tx_result
711 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
712 {
713 	struct sk_buff *skb;
714 
715 	ieee80211_tx_set_protected(tx);
716 
717 	skb_queue_walk(&tx->skbs, skb) {
718 		if (gcmp_encrypt_skb(tx, skb) < 0)
719 			return TX_DROP;
720 	}
721 
722 	return TX_CONTINUE;
723 }
724 
725 ieee80211_rx_result
726 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
727 {
728 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
729 	int hdrlen;
730 	struct ieee80211_key *key = rx->key;
731 	struct sk_buff *skb = rx->skb;
732 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
733 	u8 pn[IEEE80211_GCMP_PN_LEN];
734 	int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN;
735 
736 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
737 
738 	if (!ieee80211_is_data(hdr->frame_control) &&
739 	    !ieee80211_is_robust_mgmt_frame(skb))
740 		return RX_CONTINUE;
741 
742 	if (status->flag & RX_FLAG_DECRYPTED) {
743 		if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
744 			return RX_DROP_UNUSABLE;
745 		if (status->flag & RX_FLAG_MIC_STRIPPED)
746 			mic_len = 0;
747 	} else {
748 		if (skb_linearize(rx->skb))
749 			return RX_DROP_UNUSABLE;
750 	}
751 
752 	data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
753 	if (!rx->sta || data_len < 0)
754 		return RX_DROP_UNUSABLE;
755 
756 	if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
757 		int res;
758 
759 		gcmp_hdr2pn(pn, skb->data + hdrlen);
760 
761 		queue = rx->security_idx;
762 
763 		res = memcmp(pn, key->u.gcmp.rx_pn[queue],
764 			     IEEE80211_GCMP_PN_LEN);
765 		if (res < 0 ||
766 		    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
767 			key->u.gcmp.replays++;
768 			return RX_DROP_UNUSABLE;
769 		}
770 
771 		if (!(status->flag & RX_FLAG_DECRYPTED)) {
772 			u8 aad[2 * AES_BLOCK_SIZE];
773 			u8 j_0[AES_BLOCK_SIZE];
774 			/* hardware didn't decrypt/verify MIC */
775 			gcmp_special_blocks(skb, pn, j_0, aad);
776 
777 			if (ieee80211_aes_gcm_decrypt(
778 				    key->u.gcmp.tfm, j_0, aad,
779 				    skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
780 				    data_len,
781 				    skb->data + skb->len -
782 				    IEEE80211_GCMP_MIC_LEN))
783 				return RX_DROP_UNUSABLE;
784 		}
785 
786 		memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
787 		if (unlikely(ieee80211_is_frag(hdr)))
788 			memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN);
789 	}
790 
791 	/* Remove GCMP header and MIC */
792 	if (pskb_trim(skb, skb->len - mic_len))
793 		return RX_DROP_UNUSABLE;
794 	memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
795 	skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
796 
797 	return RX_CONTINUE;
798 }
799 
800 static ieee80211_tx_result
801 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
802 			    struct sk_buff *skb)
803 {
804 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
805 	struct ieee80211_key *key = tx->key;
806 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
807 	int hdrlen;
808 	u8 *pos, iv_len = key->conf.iv_len;
809 
810 	if (info->control.hw_key &&
811 	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
812 		/* hwaccel has no need for preallocated head room */
813 		return TX_CONTINUE;
814 	}
815 
816 	if (unlikely(skb_headroom(skb) < iv_len &&
817 		     pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
818 		return TX_DROP;
819 
820 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
821 
822 	pos = skb_push(skb, iv_len);
823 	memmove(pos, pos + iv_len, hdrlen);
824 
825 	return TX_CONTINUE;
826 }
827 
828 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
829 {
830 	int i;
831 
832 	/* pn is little endian */
833 	for (i = len - 1; i >= 0; i--) {
834 		if (pn1[i] < pn2[i])
835 			return -1;
836 		else if (pn1[i] > pn2[i])
837 			return 1;
838 	}
839 
840 	return 0;
841 }
842 
843 static ieee80211_rx_result
844 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
845 {
846 	struct ieee80211_key *key = rx->key;
847 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
848 	const struct ieee80211_cipher_scheme *cs = NULL;
849 	int hdrlen = ieee80211_hdrlen(hdr->frame_control);
850 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
851 	int data_len;
852 	u8 *rx_pn;
853 	u8 *skb_pn;
854 	u8 qos_tid;
855 
856 	if (!rx->sta || !rx->sta->cipher_scheme ||
857 	    !(status->flag & RX_FLAG_DECRYPTED))
858 		return RX_DROP_UNUSABLE;
859 
860 	if (!ieee80211_is_data(hdr->frame_control))
861 		return RX_CONTINUE;
862 
863 	cs = rx->sta->cipher_scheme;
864 
865 	data_len = rx->skb->len - hdrlen - cs->hdr_len;
866 
867 	if (data_len < 0)
868 		return RX_DROP_UNUSABLE;
869 
870 	if (ieee80211_is_data_qos(hdr->frame_control))
871 		qos_tid = ieee80211_get_tid(hdr);
872 	else
873 		qos_tid = 0;
874 
875 	if (skb_linearize(rx->skb))
876 		return RX_DROP_UNUSABLE;
877 
878 	hdr = (struct ieee80211_hdr *)rx->skb->data;
879 
880 	rx_pn = key->u.gen.rx_pn[qos_tid];
881 	skb_pn = rx->skb->data + hdrlen + cs->pn_off;
882 
883 	if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
884 		return RX_DROP_UNUSABLE;
885 
886 	memcpy(rx_pn, skb_pn, cs->pn_len);
887 
888 	/* remove security header and MIC */
889 	if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
890 		return RX_DROP_UNUSABLE;
891 
892 	memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
893 	skb_pull(rx->skb, cs->hdr_len);
894 
895 	return RX_CONTINUE;
896 }
897 
898 static void bip_aad(struct sk_buff *skb, u8 *aad)
899 {
900 	__le16 mask_fc;
901 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
902 
903 	/* BIP AAD: FC(masked) || A1 || A2 || A3 */
904 
905 	/* FC type/subtype */
906 	/* Mask FC Retry, PwrMgt, MoreData flags to zero */
907 	mask_fc = hdr->frame_control;
908 	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
909 				IEEE80211_FCTL_MOREDATA);
910 	put_unaligned(mask_fc, (__le16 *) &aad[0]);
911 	/* A1 || A2 || A3 */
912 	memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
913 }
914 
915 
916 static inline void bip_ipn_set64(u8 *d, u64 pn)
917 {
918 	*d++ = pn;
919 	*d++ = pn >> 8;
920 	*d++ = pn >> 16;
921 	*d++ = pn >> 24;
922 	*d++ = pn >> 32;
923 	*d = pn >> 40;
924 }
925 
926 static inline void bip_ipn_swap(u8 *d, const u8 *s)
927 {
928 	*d++ = s[5];
929 	*d++ = s[4];
930 	*d++ = s[3];
931 	*d++ = s[2];
932 	*d++ = s[1];
933 	*d = s[0];
934 }
935 
936 
937 ieee80211_tx_result
938 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
939 {
940 	struct sk_buff *skb;
941 	struct ieee80211_tx_info *info;
942 	struct ieee80211_key *key = tx->key;
943 	struct ieee80211_mmie *mmie;
944 	u8 aad[20];
945 	u64 pn64;
946 
947 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
948 		return TX_DROP;
949 
950 	skb = skb_peek(&tx->skbs);
951 
952 	info = IEEE80211_SKB_CB(skb);
953 
954 	if (info->control.hw_key &&
955 	    !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE))
956 		return TX_CONTINUE;
957 
958 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
959 		return TX_DROP;
960 
961 	mmie = skb_put(skb, sizeof(*mmie));
962 	mmie->element_id = WLAN_EID_MMIE;
963 	mmie->length = sizeof(*mmie) - 2;
964 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
965 
966 	/* PN = PN + 1 */
967 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
968 
969 	bip_ipn_set64(mmie->sequence_number, pn64);
970 
971 	if (info->control.hw_key)
972 		return TX_CONTINUE;
973 
974 	bip_aad(skb, aad);
975 
976 	/*
977 	 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
978 	 */
979 	ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
980 			   skb->data + 24, skb->len - 24, mmie->mic);
981 
982 	return TX_CONTINUE;
983 }
984 
985 ieee80211_tx_result
986 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
987 {
988 	struct sk_buff *skb;
989 	struct ieee80211_tx_info *info;
990 	struct ieee80211_key *key = tx->key;
991 	struct ieee80211_mmie_16 *mmie;
992 	u8 aad[20];
993 	u64 pn64;
994 
995 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
996 		return TX_DROP;
997 
998 	skb = skb_peek(&tx->skbs);
999 
1000 	info = IEEE80211_SKB_CB(skb);
1001 
1002 	if (info->control.hw_key)
1003 		return TX_CONTINUE;
1004 
1005 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1006 		return TX_DROP;
1007 
1008 	mmie = skb_put(skb, sizeof(*mmie));
1009 	mmie->element_id = WLAN_EID_MMIE;
1010 	mmie->length = sizeof(*mmie) - 2;
1011 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
1012 
1013 	/* PN = PN + 1 */
1014 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
1015 
1016 	bip_ipn_set64(mmie->sequence_number, pn64);
1017 
1018 	bip_aad(skb, aad);
1019 
1020 	/* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1021 	 */
1022 	ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1023 			       skb->data + 24, skb->len - 24, mmie->mic);
1024 
1025 	return TX_CONTINUE;
1026 }
1027 
1028 ieee80211_rx_result
1029 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1030 {
1031 	struct sk_buff *skb = rx->skb;
1032 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1033 	struct ieee80211_key *key = rx->key;
1034 	struct ieee80211_mmie *mmie;
1035 	u8 aad[20], mic[8], ipn[6];
1036 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1037 
1038 	if (!ieee80211_is_mgmt(hdr->frame_control))
1039 		return RX_CONTINUE;
1040 
1041 	/* management frames are already linear */
1042 
1043 	if (skb->len < 24 + sizeof(*mmie))
1044 		return RX_DROP_UNUSABLE;
1045 
1046 	mmie = (struct ieee80211_mmie *)
1047 		(skb->data + skb->len - sizeof(*mmie));
1048 	if (mmie->element_id != WLAN_EID_MMIE ||
1049 	    mmie->length != sizeof(*mmie) - 2)
1050 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1051 
1052 	bip_ipn_swap(ipn, mmie->sequence_number);
1053 
1054 	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1055 		key->u.aes_cmac.replays++;
1056 		return RX_DROP_UNUSABLE;
1057 	}
1058 
1059 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1060 		/* hardware didn't decrypt/verify MIC */
1061 		bip_aad(skb, aad);
1062 		ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1063 				   skb->data + 24, skb->len - 24, mic);
1064 		if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1065 			key->u.aes_cmac.icverrors++;
1066 			return RX_DROP_UNUSABLE;
1067 		}
1068 	}
1069 
1070 	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1071 
1072 	/* Remove MMIE */
1073 	skb_trim(skb, skb->len - sizeof(*mmie));
1074 
1075 	return RX_CONTINUE;
1076 }
1077 
1078 ieee80211_rx_result
1079 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1080 {
1081 	struct sk_buff *skb = rx->skb;
1082 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1083 	struct ieee80211_key *key = rx->key;
1084 	struct ieee80211_mmie_16 *mmie;
1085 	u8 aad[20], mic[16], ipn[6];
1086 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1087 
1088 	if (!ieee80211_is_mgmt(hdr->frame_control))
1089 		return RX_CONTINUE;
1090 
1091 	/* management frames are already linear */
1092 
1093 	if (skb->len < 24 + sizeof(*mmie))
1094 		return RX_DROP_UNUSABLE;
1095 
1096 	mmie = (struct ieee80211_mmie_16 *)
1097 		(skb->data + skb->len - sizeof(*mmie));
1098 	if (mmie->element_id != WLAN_EID_MMIE ||
1099 	    mmie->length != sizeof(*mmie) - 2)
1100 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1101 
1102 	bip_ipn_swap(ipn, mmie->sequence_number);
1103 
1104 	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1105 		key->u.aes_cmac.replays++;
1106 		return RX_DROP_UNUSABLE;
1107 	}
1108 
1109 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1110 		/* hardware didn't decrypt/verify MIC */
1111 		bip_aad(skb, aad);
1112 		ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1113 				       skb->data + 24, skb->len - 24, mic);
1114 		if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1115 			key->u.aes_cmac.icverrors++;
1116 			return RX_DROP_UNUSABLE;
1117 		}
1118 	}
1119 
1120 	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1121 
1122 	/* Remove MMIE */
1123 	skb_trim(skb, skb->len - sizeof(*mmie));
1124 
1125 	return RX_CONTINUE;
1126 }
1127 
1128 ieee80211_tx_result
1129 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1130 {
1131 	struct sk_buff *skb;
1132 	struct ieee80211_tx_info *info;
1133 	struct ieee80211_key *key = tx->key;
1134 	struct ieee80211_mmie_16 *mmie;
1135 	struct ieee80211_hdr *hdr;
1136 	u8 aad[GMAC_AAD_LEN];
1137 	u64 pn64;
1138 	u8 nonce[GMAC_NONCE_LEN];
1139 
1140 	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1141 		return TX_DROP;
1142 
1143 	skb = skb_peek(&tx->skbs);
1144 
1145 	info = IEEE80211_SKB_CB(skb);
1146 
1147 	if (info->control.hw_key)
1148 		return TX_CONTINUE;
1149 
1150 	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1151 		return TX_DROP;
1152 
1153 	mmie = skb_put(skb, sizeof(*mmie));
1154 	mmie->element_id = WLAN_EID_MMIE;
1155 	mmie->length = sizeof(*mmie) - 2;
1156 	mmie->key_id = cpu_to_le16(key->conf.keyidx);
1157 
1158 	/* PN = PN + 1 */
1159 	pn64 = atomic64_inc_return(&key->conf.tx_pn);
1160 
1161 	bip_ipn_set64(mmie->sequence_number, pn64);
1162 
1163 	bip_aad(skb, aad);
1164 
1165 	hdr = (struct ieee80211_hdr *)skb->data;
1166 	memcpy(nonce, hdr->addr2, ETH_ALEN);
1167 	bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1168 
1169 	/* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1170 	if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1171 			       skb->data + 24, skb->len - 24, mmie->mic) < 0)
1172 		return TX_DROP;
1173 
1174 	return TX_CONTINUE;
1175 }
1176 
1177 ieee80211_rx_result
1178 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1179 {
1180 	struct sk_buff *skb = rx->skb;
1181 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1182 	struct ieee80211_key *key = rx->key;
1183 	struct ieee80211_mmie_16 *mmie;
1184 	u8 aad[GMAC_AAD_LEN], *mic, ipn[6], nonce[GMAC_NONCE_LEN];
1185 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1186 
1187 	if (!ieee80211_is_mgmt(hdr->frame_control))
1188 		return RX_CONTINUE;
1189 
1190 	/* management frames are already linear */
1191 
1192 	if (skb->len < 24 + sizeof(*mmie))
1193 		return RX_DROP_UNUSABLE;
1194 
1195 	mmie = (struct ieee80211_mmie_16 *)
1196 		(skb->data + skb->len - sizeof(*mmie));
1197 	if (mmie->element_id != WLAN_EID_MMIE ||
1198 	    mmie->length != sizeof(*mmie) - 2)
1199 		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1200 
1201 	bip_ipn_swap(ipn, mmie->sequence_number);
1202 
1203 	if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1204 		key->u.aes_gmac.replays++;
1205 		return RX_DROP_UNUSABLE;
1206 	}
1207 
1208 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1209 		/* hardware didn't decrypt/verify MIC */
1210 		bip_aad(skb, aad);
1211 
1212 		memcpy(nonce, hdr->addr2, ETH_ALEN);
1213 		memcpy(nonce + ETH_ALEN, ipn, 6);
1214 
1215 		mic = kmalloc(GMAC_MIC_LEN, GFP_ATOMIC);
1216 		if (!mic)
1217 			return RX_DROP_UNUSABLE;
1218 		if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1219 				       skb->data + 24, skb->len - 24,
1220 				       mic) < 0 ||
1221 		    crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1222 			key->u.aes_gmac.icverrors++;
1223 			kfree(mic);
1224 			return RX_DROP_UNUSABLE;
1225 		}
1226 		kfree(mic);
1227 	}
1228 
1229 	memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1230 
1231 	/* Remove MMIE */
1232 	skb_trim(skb, skb->len - sizeof(*mmie));
1233 
1234 	return RX_CONTINUE;
1235 }
1236 
1237 ieee80211_tx_result
1238 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1239 {
1240 	struct sk_buff *skb;
1241 	struct ieee80211_tx_info *info = NULL;
1242 	ieee80211_tx_result res;
1243 
1244 	skb_queue_walk(&tx->skbs, skb) {
1245 		info  = IEEE80211_SKB_CB(skb);
1246 
1247 		/* handle hw-only algorithm */
1248 		if (!info->control.hw_key)
1249 			return TX_DROP;
1250 
1251 		if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1252 			res = ieee80211_crypto_cs_encrypt(tx, skb);
1253 			if (res != TX_CONTINUE)
1254 				return res;
1255 		}
1256 	}
1257 
1258 	ieee80211_tx_set_protected(tx);
1259 
1260 	return TX_CONTINUE;
1261 }
1262 
1263 ieee80211_rx_result
1264 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1265 {
1266 	if (rx->sta && rx->sta->cipher_scheme)
1267 		return ieee80211_crypto_cs_decrypt(rx);
1268 
1269 	return RX_DROP_UNUSABLE;
1270 }
1271