mwifiex: delete IEs when stop_ap
[deliverable/linux.git] / net / mac80211 / wpa.c
CommitLineData
f0706e82
JB
1/*
2 * Copyright 2002-2004, Instant802 Networks, Inc.
765cb46a 3 * Copyright 2008, Jouni Malinen <j@w1.fi>
f0706e82
JB
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>
f0706e82
JB
12#include <linux/skbuff.h>
13#include <linux/compiler.h>
f14df804 14#include <linux/ieee80211.h>
5a0e3ad6 15#include <linux/gfp.h>
f14df804 16#include <asm/unaligned.h>
f0706e82 17#include <net/mac80211.h>
aba83a0b 18#include <crypto/aes.h>
eb063c17 19
f0706e82
JB
20#include "ieee80211_i.h"
21#include "michael.h"
22#include "tkip.h"
23#include "aes_ccm.h"
765cb46a 24#include "aes_cmac.h"
f0706e82
JB
25#include "wpa.h"
26
9ae54c84 27ieee80211_tx_result
5cf121c3 28ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
f0706e82 29{
747d753d 30 u8 *data, *key, *mic;
f0706e82 31 size_t data_len;
8e8862b7
HH
32 unsigned int hdrlen;
33 struct ieee80211_hdr *hdr;
f0706e82 34 struct sk_buff *skb = tx->skb;
813d7669 35 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
23c0752a 36 int tail;
f0706e82 37
c34498b9 38 hdr = (struct ieee80211_hdr *)skb->data;
97359d12
JB
39 if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
40 skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
9ae54c84 41 return TX_CONTINUE;
f0706e82 42
8e8862b7
HH
43 hdrlen = ieee80211_hdrlen(hdr->frame_control);
44 if (skb->len < hdrlen)
9ae54c84 45 return TX_DROP;
f0706e82 46
8e8862b7
HH
47 data = skb->data + hdrlen;
48 data_len = skb->len - hdrlen;
49
681d1190
JM
50 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
51 /* Need to use software crypto for the test */
52 info->control.hw_key = NULL;
53 }
54
813d7669 55 if (info->control.hw_key &&
a26eb27a
JB
56 (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
57 tx->local->ops->set_frag_threshold) &&
813d7669
JB
58 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
59 /* hwaccel - with no need for SW-generated MMIC */
9ae54c84 60 return TX_CONTINUE;
f0706e82
JB
61 }
62
23c0752a 63 tail = MICHAEL_MIC_LEN;
813d7669 64 if (!info->control.hw_key)
23c0752a
JB
65 tail += TKIP_ICV_LEN;
66
67 if (WARN_ON(skb_tailroom(skb) < tail ||
68 skb_headroom(skb) < TKIP_IV_LEN))
69 return TX_DROP;
f0706e82 70
747d753d 71 key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
f0706e82 72 mic = skb_put(skb, MICHAEL_MIC_LEN);
8e8862b7 73 michael_mic(key, hdr, data, data_len, mic);
681d1190
JM
74 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
75 mic[0]++;
f0706e82 76
9ae54c84 77 return TX_CONTINUE;
f0706e82
JB
78}
79
80
9ae54c84 81ieee80211_rx_result
5cf121c3 82ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
f0706e82 83{
747d753d 84 u8 *data, *key = NULL;
f0706e82 85 size_t data_len;
8e8862b7 86 unsigned int hdrlen;
f0706e82
JB
87 u8 mic[MICHAEL_MIC_LEN];
88 struct sk_buff *skb = rx->skb;
eb9fb5b8
JB
89 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
90 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
f0706e82 91
816c04fe
CL
92 /*
93 * it makes no sense to check for MIC errors on anything other
94 * than data frames.
95 */
96 if (!ieee80211_is_data_present(hdr->frame_control))
9ae54c84 97 return RX_CONTINUE;
f0706e82 98
816c04fe
CL
99 /*
100 * No way to verify the MIC if the hardware stripped it or
101 * the IV with the key index. In this case we have solely rely
102 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
103 * MIC failure report.
104 */
105 if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
106 if (status->flag & RX_FLAG_MMIC_ERROR)
107 goto mic_fail;
108
1140afa8 109 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key)
816c04fe
CL
110 goto update_iv;
111
112 return RX_CONTINUE;
113 }
114
115 /*
116 * Some hardware seems to generate Michael MIC failure reports; even
117 * though, the frame was not encrypted with TKIP and therefore has no
118 * MIC. Ignore the flag them to avoid triggering countermeasures.
119 */
97359d12 120 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
816c04fe 121 !(status->flag & RX_FLAG_DECRYPTED))
9ae54c84 122 return RX_CONTINUE;
f0706e82 123
816c04fe
CL
124 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
125 /*
126 * APs with pairwise keys should never receive Michael MIC
127 * errors for non-zero keyidx because these are reserved for
128 * group keys and only the AP is sending real multicast
129 * frames in the BSS. (
130 */
131 return RX_DROP_UNUSABLE;
132 }
133
134 if (status->flag & RX_FLAG_MMIC_ERROR)
135 goto mic_fail;
136
8e8862b7
HH
137 hdrlen = ieee80211_hdrlen(hdr->frame_control);
138 if (skb->len < hdrlen + MICHAEL_MIC_LEN)
e4c26add 139 return RX_DROP_UNUSABLE;
f0706e82 140
a8286911
JB
141 if (skb_linearize(rx->skb))
142 return RX_DROP_UNUSABLE;
143 hdr = (void *)skb->data;
144
8e8862b7
HH
145 data = skb->data + hdrlen;
146 data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
747d753d 147 key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
8e8862b7 148 michael_mic(key, hdr, data, data_len, mic);
816c04fe
CL
149 if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0)
150 goto mic_fail;
f0706e82 151
f0706e82
JB
152 /* remove Michael MIC from payload */
153 skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
154
816c04fe 155update_iv:
50741ae0 156 /* update IV in key information to be able to detect replays */
9e26297a
JB
157 rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
158 rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
50741ae0 159
9ae54c84 160 return RX_CONTINUE;
816c04fe
CL
161
162mic_fail:
a66b98db
AN
163 /*
164 * In some cases the key can be unset - e.g. a multicast packet, in
165 * a driver that supports HW encryption. Send up the key idx only if
166 * the key is set.
167 */
168 mac80211_ev_michael_mic_failure(rx->sdata,
169 rx->key ? rx->key->conf.keyidx : -1,
816c04fe
CL
170 (void *) skb->data, NULL, GFP_ATOMIC);
171 return RX_DROP_UNUSABLE;
f0706e82
JB
172}
173
174
e039fa4a 175static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
f0706e82
JB
176{
177 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
178 struct ieee80211_key *key = tx->key;
e039fa4a 179 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
523b02ea 180 unsigned long flags;
d5184cac
HH
181 unsigned int hdrlen;
182 int len, tail;
f0706e82
JB
183 u8 *pos;
184
813d7669
JB
185 if (info->control.hw_key &&
186 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
187 /* hwaccel - with no need for software-generated IV */
23c0752a 188 return 0;
e039fa4a
JB
189 }
190
d5184cac 191 hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82
JB
192 len = skb->len - hdrlen;
193
813d7669 194 if (info->control.hw_key)
23c0752a 195 tail = 0;
11a843b7 196 else
23c0752a
JB
197 tail = TKIP_ICV_LEN;
198
199 if (WARN_ON(skb_tailroom(skb) < tail ||
200 skb_headroom(skb) < TKIP_IV_LEN))
201 return -1;
f0706e82
JB
202
203 pos = skb_push(skb, TKIP_IV_LEN);
204 memmove(pos, pos + TKIP_IV_LEN, hdrlen);
205 pos += hdrlen;
206
207 /* Increase IV for the frame */
523b02ea 208 spin_lock_irqsave(&key->u.tkip.txlock, flags);
b0f76b33
HH
209 key->u.tkip.tx.iv16++;
210 if (key->u.tkip.tx.iv16 == 0)
211 key->u.tkip.tx.iv32++;
523b02ea
JB
212 pos = ieee80211_tkip_add_iv(pos, key);
213 spin_unlock_irqrestore(&key->u.tkip.txlock, flags);
f0706e82 214
813d7669
JB
215 /* hwaccel - with software IV */
216 if (info->control.hw_key)
f0706e82 217 return 0;
f0706e82
JB
218
219 /* Add room for ICV */
220 skb_put(skb, TKIP_ICV_LEN);
221
3473187d 222 return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
523b02ea 223 key, skb, pos, len);
f0706e82
JB
224}
225
226
9ae54c84 227ieee80211_tx_result
5cf121c3 228ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
f0706e82 229{
252b86c4 230 struct sk_buff *skb;
f0706e82 231
5cf121c3 232 ieee80211_tx_set_protected(tx);
f0706e82 233
252b86c4 234 skb_queue_walk(&tx->skbs, skb) {
2de8e0d9
JB
235 if (tkip_encrypt_skb(tx, skb) < 0)
236 return TX_DROP;
252b86c4 237 }
f0706e82 238
9ae54c84 239 return TX_CONTINUE;
f0706e82
JB
240}
241
242
9ae54c84 243ieee80211_rx_result
5cf121c3 244ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
f0706e82
JB
245{
246 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
747d753d 247 int hdrlen, res, hwaccel = 0;
f0706e82
JB
248 struct ieee80211_key *key = rx->key;
249 struct sk_buff *skb = rx->skb;
eb9fb5b8 250 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
f0706e82 251
d5184cac 252 hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82 253
c34498b9 254 if (!ieee80211_is_data(hdr->frame_control))
9ae54c84 255 return RX_CONTINUE;
f0706e82
JB
256
257 if (!rx->sta || skb->len - hdrlen < 12)
e4c26add 258 return RX_DROP_UNUSABLE;
f0706e82 259
a8286911
JB
260 /* it may be possible to optimize this a bit more */
261 if (skb_linearize(rx->skb))
262 return RX_DROP_UNUSABLE;
263 hdr = (void *)skb->data;
264
dc1580dd
JB
265 /*
266 * Let TKIP code verify IV, but skip decryption.
267 * In the case where hardware checks the IV as well,
268 * we don't even get here, see ieee80211_rx_h_decrypt()
269 */
270 if (status->flag & RX_FLAG_DECRYPTED)
f0706e82 271 hwaccel = 1;
f0706e82
JB
272
273 res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
274 key, skb->data + hdrlen,
17741cdc 275 skb->len - hdrlen, rx->sta->sta.addr,
9e26297a 276 hdr->addr1, hwaccel, rx->security_idx,
5cf121c3
JB
277 &rx->tkip_iv32,
278 &rx->tkip_iv16);
747d753d 279 if (res != TKIP_DECRYPT_OK)
e4c26add 280 return RX_DROP_UNUSABLE;
f0706e82
JB
281
282 /* Trim ICV */
283 skb_trim(skb, skb->len - TKIP_ICV_LEN);
284
285 /* Remove IV */
286 memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen);
287 skb_pull(skb, TKIP_IV_LEN);
288
9ae54c84 289 return RX_CONTINUE;
f0706e82
JB
290}
291
292
feccb466 293static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch,
f0706e82
JB
294 int encrypted)
295{
f14df804 296 __le16 mask_fc;
fb733336 297 int a4_included, mgmt;
f14df804 298 u8 qos_tid;
feccb466 299 u8 *b_0, *aad;
f14df804
HH
300 u16 data_len, len_a;
301 unsigned int hdrlen;
302 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
f0706e82 303
0cd20a27 304 memset(scratch, 0, 6 * AES_BLOCK_SIZE);
aba83a0b 305
0cd20a27
JB
306 b_0 = scratch + 3 * AES_BLOCK_SIZE;
307 aad = scratch + 4 * AES_BLOCK_SIZE;
feccb466 308
f14df804 309 /*
fb733336 310 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
f14df804
HH
311 * Retry, PwrMgt, MoreData; set Protected
312 */
fb733336 313 mgmt = ieee80211_is_mgmt(hdr->frame_control);
f14df804 314 mask_fc = hdr->frame_control;
fb733336 315 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
f14df804 316 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
fb733336
JM
317 if (!mgmt)
318 mask_fc &= ~cpu_to_le16(0x0070);
f14df804
HH
319 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
320
321 hdrlen = ieee80211_hdrlen(hdr->frame_control);
322 len_a = hdrlen - 2;
323 a4_included = ieee80211_has_a4(hdr->frame_control);
f0706e82 324
f14df804
HH
325 if (ieee80211_is_data_qos(hdr->frame_control))
326 qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
327 else
328 qos_tid = 0;
329
330 data_len = skb->len - hdrlen - CCMP_HDR_LEN;
331 if (encrypted)
332 data_len -= CCMP_MIC_LEN;
333
334 /* First block, b_0 */
f0706e82 335 b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
fb733336
JM
336 /* Nonce: Nonce Flags | A2 | PN
337 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
338 */
339 b_0[1] = qos_tid | (mgmt << 4);
73e1f7c8 340 memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
f0706e82
JB
341 memcpy(&b_0[8], pn, CCMP_PN_LEN);
342 /* l(m) */
f14df804 343 put_unaligned_be16(data_len, &b_0[14]);
f0706e82
JB
344
345 /* AAD (extra authenticate-only data) / masked 802.11 header
346 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
f14df804
HH
347 put_unaligned_be16(len_a, &aad[0]);
348 put_unaligned(mask_fc, (__le16 *)&aad[2]);
73e1f7c8 349 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
f0706e82
JB
350
351 /* Mask Seq#, leave Frag# */
352 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
353 aad[23] = 0;
f14df804 354
f0706e82 355 if (a4_included) {
73e1f7c8 356 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
f14df804 357 aad[30] = qos_tid;
f0706e82 358 aad[31] = 0;
f14df804 359 } else {
73e1f7c8 360 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
f14df804 361 aad[24] = qos_tid;
f0706e82
JB
362 }
363}
364
365
366static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
367{
368 hdr[0] = pn[5];
369 hdr[1] = pn[4];
370 hdr[2] = 0;
371 hdr[3] = 0x20 | (key_id << 6);
372 hdr[4] = pn[3];
373 hdr[5] = pn[2];
374 hdr[6] = pn[1];
375 hdr[7] = pn[0];
376}
377
378
c6a1fa12 379static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
f0706e82
JB
380{
381 pn[0] = hdr[7];
382 pn[1] = hdr[6];
383 pn[2] = hdr[5];
384 pn[3] = hdr[4];
385 pn[4] = hdr[1];
386 pn[5] = hdr[0];
f0706e82
JB
387}
388
389
e039fa4a 390static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
f0706e82
JB
391{
392 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
393 struct ieee80211_key *key = tx->key;
e039fa4a 394 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
23c0752a 395 int hdrlen, len, tail;
aba83a0b
JB
396 u8 *pos;
397 u8 pn[6];
398 u64 pn64;
0cd20a27 399 u8 scratch[6 * AES_BLOCK_SIZE];
f0706e82 400
813d7669 401 if (info->control.hw_key &&
077a9154
AN
402 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
403 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
813d7669
JB
404 /*
405 * hwaccel has no need for preallocated room for CCMP
406 * header or MIC fields
407 */
23c0752a 408 return 0;
e039fa4a
JB
409 }
410
d5184cac 411 hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82
JB
412 len = skb->len - hdrlen;
413
813d7669 414 if (info->control.hw_key)
23c0752a 415 tail = 0;
11a843b7 416 else
23c0752a
JB
417 tail = CCMP_MIC_LEN;
418
419 if (WARN_ON(skb_tailroom(skb) < tail ||
420 skb_headroom(skb) < CCMP_HDR_LEN))
421 return -1;
f0706e82
JB
422
423 pos = skb_push(skb, CCMP_HDR_LEN);
424 memmove(pos, pos + CCMP_HDR_LEN, hdrlen);
077a9154
AN
425
426 /* the HW only needs room for the IV, but not the actual IV */
e0830f71
AN
427 if (info->control.hw_key &&
428 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
077a9154
AN
429 return 0;
430
f0706e82
JB
431 hdr = (struct ieee80211_hdr *) pos;
432 pos += hdrlen;
433
aba83a0b 434 pn64 = atomic64_inc_return(&key->u.ccmp.tx_pn);
f0706e82 435
aba83a0b
JB
436 pn[5] = pn64;
437 pn[4] = pn64 >> 8;
438 pn[3] = pn64 >> 16;
439 pn[2] = pn64 >> 24;
440 pn[1] = pn64 >> 32;
441 pn[0] = pn64 >> 40;
f0706e82 442
8f20fc24 443 ccmp_pn2hdr(pos, pn, key->conf.keyidx);
f0706e82 444
813d7669
JB
445 /* hwaccel - with software CCMP header */
446 if (info->control.hw_key)
f0706e82 447 return 0;
f0706e82
JB
448
449 pos += CCMP_HDR_LEN;
aba83a0b
JB
450 ccmp_special_blocks(skb, pn, scratch, 0);
451 ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, pos, len,
f0706e82
JB
452 pos, skb_put(skb, CCMP_MIC_LEN));
453
454 return 0;
455}
456
457
9ae54c84 458ieee80211_tx_result
5cf121c3 459ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx)
f0706e82 460{
252b86c4 461 struct sk_buff *skb;
f0706e82 462
5cf121c3 463 ieee80211_tx_set_protected(tx);
f0706e82 464
252b86c4 465 skb_queue_walk(&tx->skbs, skb) {
2de8e0d9
JB
466 if (ccmp_encrypt_skb(tx, skb) < 0)
467 return TX_DROP;
252b86c4 468 }
f0706e82 469
9ae54c84 470 return TX_CONTINUE;
f0706e82
JB
471}
472
473
9ae54c84 474ieee80211_rx_result
5cf121c3 475ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
f0706e82 476{
c34498b9 477 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
f0706e82
JB
478 int hdrlen;
479 struct ieee80211_key *key = rx->key;
480 struct sk_buff *skb = rx->skb;
eb9fb5b8 481 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
f0706e82
JB
482 u8 pn[CCMP_PN_LEN];
483 int data_len;
9190252c 484 int queue;
f0706e82 485
d5184cac 486 hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82 487
fb733336
JM
488 if (!ieee80211_is_data(hdr->frame_control) &&
489 !ieee80211_is_robust_mgmt_frame(hdr))
9ae54c84 490 return RX_CONTINUE;
f0706e82
JB
491
492 data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
493 if (!rx->sta || data_len < 0)
e4c26add 494 return RX_DROP_UNUSABLE;
f0706e82 495
a8286911
JB
496 if (status->flag & RX_FLAG_DECRYPTED) {
497 if (!pskb_may_pull(rx->skb, hdrlen + CCMP_HDR_LEN))
498 return RX_DROP_UNUSABLE;
499 } else {
500 if (skb_linearize(rx->skb))
501 return RX_DROP_UNUSABLE;
502 }
503
c6a1fa12 504 ccmp_hdr2pn(pn, skb->data + hdrlen);
f0706e82 505
9e26297a 506 queue = rx->security_idx;
9190252c
JM
507
508 if (memcmp(pn, key->u.ccmp.rx_pn[queue], CCMP_PN_LEN) <= 0) {
f0706e82 509 key->u.ccmp.replays++;
e4c26add 510 return RX_DROP_UNUSABLE;
f0706e82
JB
511 }
512
eb9fb5b8 513 if (!(status->flag & RX_FLAG_DECRYPTED)) {
0cd20a27 514 u8 scratch[6 * AES_BLOCK_SIZE];
7848ba7d 515 /* hardware didn't decrypt/verify MIC */
aba83a0b 516 ccmp_special_blocks(skb, pn, scratch, 1);
f0706e82
JB
517
518 if (ieee80211_aes_ccm_decrypt(
aba83a0b 519 key->u.ccmp.tfm, scratch,
f0706e82
JB
520 skb->data + hdrlen + CCMP_HDR_LEN, data_len,
521 skb->data + skb->len - CCMP_MIC_LEN,
c6a1fa12 522 skb->data + hdrlen + CCMP_HDR_LEN))
e4c26add 523 return RX_DROP_UNUSABLE;
f0706e82
JB
524 }
525
9190252c 526 memcpy(key->u.ccmp.rx_pn[queue], pn, CCMP_PN_LEN);
f0706e82
JB
527
528 /* Remove CCMP header and MIC */
a8286911
JB
529 if (pskb_trim(skb, skb->len - CCMP_MIC_LEN))
530 return RX_DROP_UNUSABLE;
f0706e82
JB
531 memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen);
532 skb_pull(skb, CCMP_HDR_LEN);
533
9ae54c84 534 return RX_CONTINUE;
f0706e82 535}
765cb46a
JM
536
537
538static void bip_aad(struct sk_buff *skb, u8 *aad)
539{
540 /* BIP AAD: FC(masked) || A1 || A2 || A3 */
541
542 /* FC type/subtype */
543 aad[0] = skb->data[0];
544 /* Mask FC Retry, PwrMgt, MoreData flags to zero */
545 aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6));
546 /* A1 || A2 || A3 */
547 memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN);
548}
549
550
75396ae6
JB
551static inline void bip_ipn_set64(u8 *d, u64 pn)
552{
553 *d++ = pn;
554 *d++ = pn >> 8;
555 *d++ = pn >> 16;
556 *d++ = pn >> 24;
557 *d++ = pn >> 32;
558 *d = pn >> 40;
559}
560
765cb46a
JM
561static inline void bip_ipn_swap(u8 *d, const u8 *s)
562{
563 *d++ = s[5];
564 *d++ = s[4];
565 *d++ = s[3];
566 *d++ = s[2];
567 *d++ = s[1];
568 *d = s[0];
569}
570
571
572ieee80211_tx_result
573ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
574{
252b86c4
JB
575 struct sk_buff *skb;
576 struct ieee80211_tx_info *info;
765cb46a
JM
577 struct ieee80211_key *key = tx->key;
578 struct ieee80211_mmie *mmie;
75396ae6
JB
579 u8 aad[20];
580 u64 pn64;
765cb46a 581
252b86c4
JB
582 if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
583 return TX_DROP;
584
585 skb = skb_peek(&tx->skbs);
586
587 info = IEEE80211_SKB_CB(skb);
588
813d7669 589 if (info->control.hw_key)
252b86c4 590 return TX_CONTINUE;
765cb46a
JM
591
592 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
593 return TX_DROP;
594
595 mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
596 mmie->element_id = WLAN_EID_MMIE;
597 mmie->length = sizeof(*mmie) - 2;
598 mmie->key_id = cpu_to_le16(key->conf.keyidx);
599
600 /* PN = PN + 1 */
75396ae6 601 pn64 = atomic64_inc_return(&key->u.aes_cmac.tx_pn);
765cb46a 602
75396ae6 603 bip_ipn_set64(mmie->sequence_number, pn64);
765cb46a
JM
604
605 bip_aad(skb, aad);
606
607 /*
608 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
609 */
75396ae6
JB
610 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
611 skb->data + 24, skb->len - 24, mmie->mic);
765cb46a
JM
612
613 return TX_CONTINUE;
614}
615
616
617ieee80211_rx_result
618ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
619{
620 struct sk_buff *skb = rx->skb;
eb9fb5b8 621 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
765cb46a
JM
622 struct ieee80211_key *key = rx->key;
623 struct ieee80211_mmie *mmie;
624 u8 aad[20], mic[8], ipn[6];
625 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
626
627 if (!ieee80211_is_mgmt(hdr->frame_control))
628 return RX_CONTINUE;
629
a8286911
JB
630 /* management frames are already linear */
631
765cb46a
JM
632 if (skb->len < 24 + sizeof(*mmie))
633 return RX_DROP_UNUSABLE;
634
635 mmie = (struct ieee80211_mmie *)
636 (skb->data + skb->len - sizeof(*mmie));
637 if (mmie->element_id != WLAN_EID_MMIE ||
638 mmie->length != sizeof(*mmie) - 2)
639 return RX_DROP_UNUSABLE; /* Invalid MMIE */
640
641 bip_ipn_swap(ipn, mmie->sequence_number);
642
643 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
644 key->u.aes_cmac.replays++;
645 return RX_DROP_UNUSABLE;
646 }
647
eb9fb5b8 648 if (!(status->flag & RX_FLAG_DECRYPTED)) {
765cb46a
JM
649 /* hardware didn't decrypt/verify MIC */
650 bip_aad(skb, aad);
75396ae6 651 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
765cb46a
JM
652 skb->data + 24, skb->len - 24, mic);
653 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
654 key->u.aes_cmac.icverrors++;
655 return RX_DROP_UNUSABLE;
656 }
657 }
658
659 memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
660
661 /* Remove MMIE */
662 skb_trim(skb, skb->len - sizeof(*mmie));
663
664 return RX_CONTINUE;
665}
d32a1028
YD
666
667ieee80211_tx_result
668ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
669{
670 struct sk_buff *skb;
671 struct ieee80211_tx_info *info = NULL;
672
673 skb_queue_walk(&tx->skbs, skb) {
674 info = IEEE80211_SKB_CB(skb);
675
676 /* handle hw-only algorithm */
677 if (!info->control.hw_key)
678 return TX_DROP;
679 }
680
681 ieee80211_tx_set_protected(tx);
682
683 return TX_CONTINUE;
684}
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