staging/rdma/hfi1: select CRC32
[linux-2.6/btrfs-unstable.git] / net / mac80211 / wpa.c
blob18848258adde8bdf855829cbce15d388d84a3eef
1 /*
2 * Copyright 2002-2004, Instant802 Networks, Inc.
3 * Copyright 2008, Jouni Malinen <j@w1.fi>
4 * Copyright (C) 2016 Intel Deutschland GmbH
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
11 #include <linux/netdevice.h>
12 #include <linux/types.h>
13 #include <linux/skbuff.h>
14 #include <linux/compiler.h>
15 #include <linux/ieee80211.h>
16 #include <linux/gfp.h>
17 #include <asm/unaligned.h>
18 #include <net/mac80211.h>
19 #include <crypto/aes.h>
21 #include "ieee80211_i.h"
22 #include "michael.h"
23 #include "tkip.h"
24 #include "aes_ccm.h"
25 #include "aes_cmac.h"
26 #include "aes_gmac.h"
27 #include "aes_gcm.h"
28 #include "wpa.h"
30 ieee80211_tx_result
31 ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
33 u8 *data, *key, *mic;
34 size_t data_len;
35 unsigned int hdrlen;
36 struct ieee80211_hdr *hdr;
37 struct sk_buff *skb = tx->skb;
38 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
39 int tail;
41 hdr = (struct ieee80211_hdr *)skb->data;
42 if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
43 skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
44 return TX_CONTINUE;
46 hdrlen = ieee80211_hdrlen(hdr->frame_control);
47 if (skb->len < hdrlen)
48 return TX_DROP;
50 data = skb->data + hdrlen;
51 data_len = skb->len - hdrlen;
53 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
54 /* Need to use software crypto for the test */
55 info->control.hw_key = NULL;
58 if (info->control.hw_key &&
59 (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
60 tx->local->ops->set_frag_threshold) &&
61 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
62 /* hwaccel - with no need for SW-generated MMIC */
63 return TX_CONTINUE;
66 tail = MICHAEL_MIC_LEN;
67 if (!info->control.hw_key)
68 tail += IEEE80211_TKIP_ICV_LEN;
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;
77 key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
78 mic = skb_put(skb, MICHAEL_MIC_LEN);
79 michael_mic(key, hdr, data, data_len, mic);
80 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
81 mic[0]++;
83 return TX_CONTINUE;
87 ieee80211_rx_result
88 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
90 u8 *data, *key = NULL;
91 size_t data_len;
92 unsigned int hdrlen;
93 u8 mic[MICHAEL_MIC_LEN];
94 struct sk_buff *skb = rx->skb;
95 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
96 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
99 * it makes no sense to check for MIC errors on anything other
100 * than data frames.
102 if (!ieee80211_is_data_present(hdr->frame_control))
103 return RX_CONTINUE;
106 * No way to verify the MIC if the hardware stripped it or
107 * the IV with the key index. In this case we have solely rely
108 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
109 * MIC failure report.
111 if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
112 if (status->flag & RX_FLAG_MMIC_ERROR)
113 goto mic_fail_no_key;
115 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
116 rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
117 goto update_iv;
119 return RX_CONTINUE;
123 * Some hardware seems to generate Michael MIC failure reports; even
124 * though, the frame was not encrypted with TKIP and therefore has no
125 * MIC. Ignore the flag them to avoid triggering countermeasures.
127 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
128 !(status->flag & RX_FLAG_DECRYPTED))
129 return RX_CONTINUE;
131 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
133 * APs with pairwise keys should never receive Michael MIC
134 * errors for non-zero keyidx because these are reserved for
135 * group keys and only the AP is sending real multicast
136 * frames in the BSS.
138 return RX_DROP_UNUSABLE;
141 if (status->flag & RX_FLAG_MMIC_ERROR)
142 goto mic_fail;
144 hdrlen = ieee80211_hdrlen(hdr->frame_control);
145 if (skb->len < hdrlen + MICHAEL_MIC_LEN)
146 return RX_DROP_UNUSABLE;
148 if (skb_linearize(rx->skb))
149 return RX_DROP_UNUSABLE;
150 hdr = (void *)skb->data;
152 data = skb->data + hdrlen;
153 data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
154 key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
155 michael_mic(key, hdr, data, data_len, mic);
156 if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0)
157 goto mic_fail;
159 /* remove Michael MIC from payload */
160 skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
162 update_iv:
163 /* update IV in key information to be able to detect replays */
164 rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
165 rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
167 return RX_CONTINUE;
169 mic_fail:
170 rx->key->u.tkip.mic_failures++;
172 mic_fail_no_key:
174 * In some cases the key can be unset - e.g. a multicast packet, in
175 * a driver that supports HW encryption. Send up the key idx only if
176 * the key is set.
178 cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2,
179 is_multicast_ether_addr(hdr->addr1) ?
180 NL80211_KEYTYPE_GROUP :
181 NL80211_KEYTYPE_PAIRWISE,
182 rx->key ? rx->key->conf.keyidx : -1,
183 NULL, GFP_ATOMIC);
184 return RX_DROP_UNUSABLE;
187 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
189 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
190 struct ieee80211_key *key = tx->key;
191 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
192 unsigned int hdrlen;
193 int len, tail;
194 u64 pn;
195 u8 *pos;
197 if (info->control.hw_key &&
198 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
199 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
200 /* hwaccel - with no need for software-generated IV */
201 return 0;
204 hdrlen = ieee80211_hdrlen(hdr->frame_control);
205 len = skb->len - hdrlen;
207 if (info->control.hw_key)
208 tail = 0;
209 else
210 tail = IEEE80211_TKIP_ICV_LEN;
212 if (WARN_ON(skb_tailroom(skb) < tail ||
213 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
214 return -1;
216 pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
217 memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
218 pos += hdrlen;
220 /* the HW only needs room for the IV, but not the actual IV */
221 if (info->control.hw_key &&
222 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
223 return 0;
225 /* Increase IV for the frame */
226 pn = atomic64_inc_return(&key->conf.tx_pn);
227 pos = ieee80211_tkip_add_iv(pos, &key->conf, pn);
229 /* hwaccel - with software IV */
230 if (info->control.hw_key)
231 return 0;
233 /* Add room for ICV */
234 skb_put(skb, IEEE80211_TKIP_ICV_LEN);
236 return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
237 key, skb, pos, len);
241 ieee80211_tx_result
242 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
244 struct sk_buff *skb;
246 ieee80211_tx_set_protected(tx);
248 skb_queue_walk(&tx->skbs, skb) {
249 if (tkip_encrypt_skb(tx, skb) < 0)
250 return TX_DROP;
253 return TX_CONTINUE;
257 ieee80211_rx_result
258 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
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);
266 hdrlen = ieee80211_hdrlen(hdr->frame_control);
268 if (!ieee80211_is_data(hdr->frame_control))
269 return RX_CONTINUE;
271 if (!rx->sta || skb->len - hdrlen < 12)
272 return RX_DROP_UNUSABLE;
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;
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()
284 if (status->flag & RX_FLAG_DECRYPTED)
285 hwaccel = 1;
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;
296 /* Trim ICV */
297 skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN);
299 /* Remove IV */
300 memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen);
301 skb_pull(skb, IEEE80211_TKIP_IV_LEN);
303 return RX_CONTINUE;
307 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad)
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;
317 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
318 * Retry, PwrMgt, MoreData; set Protected
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);
328 hdrlen = ieee80211_hdrlen(hdr->frame_control);
329 len_a = hdrlen - 2;
330 a4_included = ieee80211_has_a4(hdr->frame_control);
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;
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.
344 b_0[0] = 0x1;
346 /* Nonce: Nonce Flags | A2 | PN
347 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
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);
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);
359 /* Mask Seq#, leave Frag# */
360 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
361 aad[23] = 0;
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;
374 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
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];
387 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
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];
398 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
399 unsigned int mic_len)
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];
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))) {
418 * hwaccel has no need for preallocated room for CCMP
419 * header or MIC fields
421 return 0;
424 hdrlen = ieee80211_hdrlen(hdr->frame_control);
425 len = skb->len - hdrlen;
427 if (info->control.hw_key)
428 tail = 0;
429 else
430 tail = mic_len;
432 if (WARN_ON(skb_tailroom(skb) < tail ||
433 skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN))
434 return -1;
436 pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN);
437 memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen);
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;
444 hdr = (struct ieee80211_hdr *) pos;
445 pos += hdrlen;
447 pn64 = atomic64_inc_return(&key->conf.tx_pn);
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;
456 ccmp_pn2hdr(pos, pn, key->conf.keyidx);
458 /* hwaccel - with software CCMP header */
459 if (info->control.hw_key)
460 return 0;
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);
467 return 0;
471 ieee80211_tx_result
472 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx,
473 unsigned int mic_len)
475 struct sk_buff *skb;
477 ieee80211_tx_set_protected(tx);
479 skb_queue_walk(&tx->skbs, skb) {
480 if (ccmp_encrypt_skb(tx, skb, mic_len) < 0)
481 return TX_DROP;
484 return TX_CONTINUE;
488 ieee80211_rx_result
489 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
490 unsigned int mic_len)
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;
501 hdrlen = ieee80211_hdrlen(hdr->frame_control);
503 if (!ieee80211_is_data(hdr->frame_control) &&
504 !ieee80211_is_robust_mgmt_frame(skb))
505 return RX_CONTINUE;
507 data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
508 if (!rx->sta || data_len < 0)
509 return RX_DROP_UNUSABLE;
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;
519 if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
520 ccmp_hdr2pn(pn, skb->data + hdrlen);
522 queue = rx->security_idx;
524 if (memcmp(pn, key->u.ccmp.rx_pn[queue],
525 IEEE80211_CCMP_PN_LEN) <= 0) {
526 key->u.ccmp.replays++;
527 return RX_DROP_UNUSABLE;
530 if (!(status->flag & RX_FLAG_DECRYPTED)) {
531 u8 aad[2 * AES_BLOCK_SIZE];
532 u8 b_0[AES_BLOCK_SIZE];
533 /* hardware didn't decrypt/verify MIC */
534 ccmp_special_blocks(skb, pn, b_0, aad);
536 if (ieee80211_aes_ccm_decrypt(
537 key->u.ccmp.tfm, b_0, aad,
538 skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
539 data_len,
540 skb->data + skb->len - mic_len, mic_len))
541 return RX_DROP_UNUSABLE;
544 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
547 /* Remove CCMP header and MIC */
548 if (pskb_trim(skb, skb->len - mic_len))
549 return RX_DROP_UNUSABLE;
550 memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
551 skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
553 return RX_CONTINUE;
556 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
558 __le16 mask_fc;
559 u8 qos_tid;
560 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
562 memcpy(j_0, hdr->addr2, ETH_ALEN);
563 memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
564 j_0[13] = 0;
565 j_0[14] = 0;
566 j_0[AES_BLOCK_SIZE - 1] = 0x01;
568 /* AAD (extra authenticate-only data) / masked 802.11 header
569 * FC | A1 | A2 | A3 | SC | [A4] | [QC]
571 put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
572 /* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
573 * Retry, PwrMgt, MoreData; set Protected
575 mask_fc = hdr->frame_control;
576 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
577 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
578 if (!ieee80211_is_mgmt(hdr->frame_control))
579 mask_fc &= ~cpu_to_le16(0x0070);
580 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
582 put_unaligned(mask_fc, (__le16 *)&aad[2]);
583 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
585 /* Mask Seq#, leave Frag# */
586 aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
587 aad[23] = 0;
589 if (ieee80211_is_data_qos(hdr->frame_control))
590 qos_tid = *ieee80211_get_qos_ctl(hdr) &
591 IEEE80211_QOS_CTL_TID_MASK;
592 else
593 qos_tid = 0;
595 if (ieee80211_has_a4(hdr->frame_control)) {
596 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
597 aad[30] = qos_tid;
598 aad[31] = 0;
599 } else {
600 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
601 aad[24] = qos_tid;
605 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
607 hdr[0] = pn[5];
608 hdr[1] = pn[4];
609 hdr[2] = 0;
610 hdr[3] = 0x20 | (key_id << 6);
611 hdr[4] = pn[3];
612 hdr[5] = pn[2];
613 hdr[6] = pn[1];
614 hdr[7] = pn[0];
617 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
619 pn[0] = hdr[7];
620 pn[1] = hdr[6];
621 pn[2] = hdr[5];
622 pn[3] = hdr[4];
623 pn[4] = hdr[1];
624 pn[5] = hdr[0];
627 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
629 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
630 struct ieee80211_key *key = tx->key;
631 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
632 int hdrlen, len, tail;
633 u8 *pos;
634 u8 pn[6];
635 u64 pn64;
636 u8 aad[2 * AES_BLOCK_SIZE];
637 u8 j_0[AES_BLOCK_SIZE];
639 if (info->control.hw_key &&
640 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
641 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
642 !((info->control.hw_key->flags &
643 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
644 ieee80211_is_mgmt(hdr->frame_control))) {
645 /* hwaccel has no need for preallocated room for GCMP
646 * header or MIC fields
648 return 0;
651 hdrlen = ieee80211_hdrlen(hdr->frame_control);
652 len = skb->len - hdrlen;
654 if (info->control.hw_key)
655 tail = 0;
656 else
657 tail = IEEE80211_GCMP_MIC_LEN;
659 if (WARN_ON(skb_tailroom(skb) < tail ||
660 skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
661 return -1;
663 pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
664 memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
665 skb_set_network_header(skb, skb_network_offset(skb) +
666 IEEE80211_GCMP_HDR_LEN);
668 /* the HW only needs room for the IV, but not the actual IV */
669 if (info->control.hw_key &&
670 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
671 return 0;
673 hdr = (struct ieee80211_hdr *)pos;
674 pos += hdrlen;
676 pn64 = atomic64_inc_return(&key->conf.tx_pn);
678 pn[5] = pn64;
679 pn[4] = pn64 >> 8;
680 pn[3] = pn64 >> 16;
681 pn[2] = pn64 >> 24;
682 pn[1] = pn64 >> 32;
683 pn[0] = pn64 >> 40;
685 gcmp_pn2hdr(pos, pn, key->conf.keyidx);
687 /* hwaccel - with software GCMP header */
688 if (info->control.hw_key)
689 return 0;
691 pos += IEEE80211_GCMP_HDR_LEN;
692 gcmp_special_blocks(skb, pn, j_0, aad);
693 ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
694 skb_put(skb, IEEE80211_GCMP_MIC_LEN));
696 return 0;
699 ieee80211_tx_result
700 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
702 struct sk_buff *skb;
704 ieee80211_tx_set_protected(tx);
706 skb_queue_walk(&tx->skbs, skb) {
707 if (gcmp_encrypt_skb(tx, skb) < 0)
708 return TX_DROP;
711 return TX_CONTINUE;
714 ieee80211_rx_result
715 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
717 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
718 int hdrlen;
719 struct ieee80211_key *key = rx->key;
720 struct sk_buff *skb = rx->skb;
721 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
722 u8 pn[IEEE80211_GCMP_PN_LEN];
723 int data_len;
724 int queue;
726 hdrlen = ieee80211_hdrlen(hdr->frame_control);
728 if (!ieee80211_is_data(hdr->frame_control) &&
729 !ieee80211_is_robust_mgmt_frame(skb))
730 return RX_CONTINUE;
732 data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN -
733 IEEE80211_GCMP_MIC_LEN;
734 if (!rx->sta || data_len < 0)
735 return RX_DROP_UNUSABLE;
737 if (status->flag & RX_FLAG_DECRYPTED) {
738 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
739 return RX_DROP_UNUSABLE;
740 } else {
741 if (skb_linearize(rx->skb))
742 return RX_DROP_UNUSABLE;
745 if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
746 gcmp_hdr2pn(pn, skb->data + hdrlen);
748 queue = rx->security_idx;
750 if (memcmp(pn, key->u.gcmp.rx_pn[queue],
751 IEEE80211_GCMP_PN_LEN) <= 0) {
752 key->u.gcmp.replays++;
753 return RX_DROP_UNUSABLE;
756 if (!(status->flag & RX_FLAG_DECRYPTED)) {
757 u8 aad[2 * AES_BLOCK_SIZE];
758 u8 j_0[AES_BLOCK_SIZE];
759 /* hardware didn't decrypt/verify MIC */
760 gcmp_special_blocks(skb, pn, j_0, aad);
762 if (ieee80211_aes_gcm_decrypt(
763 key->u.gcmp.tfm, j_0, aad,
764 skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
765 data_len,
766 skb->data + skb->len -
767 IEEE80211_GCMP_MIC_LEN))
768 return RX_DROP_UNUSABLE;
771 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
774 /* Remove GCMP header and MIC */
775 if (pskb_trim(skb, skb->len - IEEE80211_GCMP_MIC_LEN))
776 return RX_DROP_UNUSABLE;
777 memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
778 skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
780 return RX_CONTINUE;
783 static ieee80211_tx_result
784 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
785 struct sk_buff *skb)
787 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
788 struct ieee80211_key *key = tx->key;
789 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
790 int hdrlen;
791 u8 *pos, iv_len = key->conf.iv_len;
793 if (info->control.hw_key &&
794 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
795 /* hwaccel has no need for preallocated head room */
796 return TX_CONTINUE;
799 if (unlikely(skb_headroom(skb) < iv_len &&
800 pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
801 return TX_DROP;
803 hdrlen = ieee80211_hdrlen(hdr->frame_control);
805 pos = skb_push(skb, iv_len);
806 memmove(pos, pos + iv_len, hdrlen);
808 return TX_CONTINUE;
811 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
813 int i;
815 /* pn is little endian */
816 for (i = len - 1; i >= 0; i--) {
817 if (pn1[i] < pn2[i])
818 return -1;
819 else if (pn1[i] > pn2[i])
820 return 1;
823 return 0;
826 static ieee80211_rx_result
827 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
829 struct ieee80211_key *key = rx->key;
830 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
831 const struct ieee80211_cipher_scheme *cs = NULL;
832 int hdrlen = ieee80211_hdrlen(hdr->frame_control);
833 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
834 int data_len;
835 u8 *rx_pn;
836 u8 *skb_pn;
837 u8 qos_tid;
839 if (!rx->sta || !rx->sta->cipher_scheme ||
840 !(status->flag & RX_FLAG_DECRYPTED))
841 return RX_DROP_UNUSABLE;
843 if (!ieee80211_is_data(hdr->frame_control))
844 return RX_CONTINUE;
846 cs = rx->sta->cipher_scheme;
848 data_len = rx->skb->len - hdrlen - cs->hdr_len;
850 if (data_len < 0)
851 return RX_DROP_UNUSABLE;
853 if (ieee80211_is_data_qos(hdr->frame_control))
854 qos_tid = *ieee80211_get_qos_ctl(hdr) &
855 IEEE80211_QOS_CTL_TID_MASK;
856 else
857 qos_tid = 0;
859 if (skb_linearize(rx->skb))
860 return RX_DROP_UNUSABLE;
862 hdr = (struct ieee80211_hdr *)rx->skb->data;
864 rx_pn = key->u.gen.rx_pn[qos_tid];
865 skb_pn = rx->skb->data + hdrlen + cs->pn_off;
867 if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
868 return RX_DROP_UNUSABLE;
870 memcpy(rx_pn, skb_pn, cs->pn_len);
872 /* remove security header and MIC */
873 if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
874 return RX_DROP_UNUSABLE;
876 memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
877 skb_pull(rx->skb, cs->hdr_len);
879 return RX_CONTINUE;
882 static void bip_aad(struct sk_buff *skb, u8 *aad)
884 __le16 mask_fc;
885 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
887 /* BIP AAD: FC(masked) || A1 || A2 || A3 */
889 /* FC type/subtype */
890 /* Mask FC Retry, PwrMgt, MoreData flags to zero */
891 mask_fc = hdr->frame_control;
892 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
893 IEEE80211_FCTL_MOREDATA);
894 put_unaligned(mask_fc, (__le16 *) &aad[0]);
895 /* A1 || A2 || A3 */
896 memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
900 static inline void bip_ipn_set64(u8 *d, u64 pn)
902 *d++ = pn;
903 *d++ = pn >> 8;
904 *d++ = pn >> 16;
905 *d++ = pn >> 24;
906 *d++ = pn >> 32;
907 *d = pn >> 40;
910 static inline void bip_ipn_swap(u8 *d, const u8 *s)
912 *d++ = s[5];
913 *d++ = s[4];
914 *d++ = s[3];
915 *d++ = s[2];
916 *d++ = s[1];
917 *d = s[0];
921 ieee80211_tx_result
922 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
924 struct sk_buff *skb;
925 struct ieee80211_tx_info *info;
926 struct ieee80211_key *key = tx->key;
927 struct ieee80211_mmie *mmie;
928 u8 aad[20];
929 u64 pn64;
931 if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
932 return TX_DROP;
934 skb = skb_peek(&tx->skbs);
936 info = IEEE80211_SKB_CB(skb);
938 if (info->control.hw_key)
939 return TX_CONTINUE;
941 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
942 return TX_DROP;
944 mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
945 mmie->element_id = WLAN_EID_MMIE;
946 mmie->length = sizeof(*mmie) - 2;
947 mmie->key_id = cpu_to_le16(key->conf.keyidx);
949 /* PN = PN + 1 */
950 pn64 = atomic64_inc_return(&key->conf.tx_pn);
952 bip_ipn_set64(mmie->sequence_number, pn64);
954 bip_aad(skb, aad);
957 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
959 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
960 skb->data + 24, skb->len - 24, mmie->mic);
962 return TX_CONTINUE;
965 ieee80211_tx_result
966 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
968 struct sk_buff *skb;
969 struct ieee80211_tx_info *info;
970 struct ieee80211_key *key = tx->key;
971 struct ieee80211_mmie_16 *mmie;
972 u8 aad[20];
973 u64 pn64;
975 if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
976 return TX_DROP;
978 skb = skb_peek(&tx->skbs);
980 info = IEEE80211_SKB_CB(skb);
982 if (info->control.hw_key)
983 return TX_CONTINUE;
985 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
986 return TX_DROP;
988 mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
989 mmie->element_id = WLAN_EID_MMIE;
990 mmie->length = sizeof(*mmie) - 2;
991 mmie->key_id = cpu_to_le16(key->conf.keyidx);
993 /* PN = PN + 1 */
994 pn64 = atomic64_inc_return(&key->conf.tx_pn);
996 bip_ipn_set64(mmie->sequence_number, pn64);
998 bip_aad(skb, aad);
1000 /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1002 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1003 skb->data + 24, skb->len - 24, mmie->mic);
1005 return TX_CONTINUE;
1008 ieee80211_rx_result
1009 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1011 struct sk_buff *skb = rx->skb;
1012 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1013 struct ieee80211_key *key = rx->key;
1014 struct ieee80211_mmie *mmie;
1015 u8 aad[20], mic[8], ipn[6];
1016 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1018 if (!ieee80211_is_mgmt(hdr->frame_control))
1019 return RX_CONTINUE;
1021 /* management frames are already linear */
1023 if (skb->len < 24 + sizeof(*mmie))
1024 return RX_DROP_UNUSABLE;
1026 mmie = (struct ieee80211_mmie *)
1027 (skb->data + skb->len - sizeof(*mmie));
1028 if (mmie->element_id != WLAN_EID_MMIE ||
1029 mmie->length != sizeof(*mmie) - 2)
1030 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1032 bip_ipn_swap(ipn, mmie->sequence_number);
1034 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1035 key->u.aes_cmac.replays++;
1036 return RX_DROP_UNUSABLE;
1039 if (!(status->flag & RX_FLAG_DECRYPTED)) {
1040 /* hardware didn't decrypt/verify MIC */
1041 bip_aad(skb, aad);
1042 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1043 skb->data + 24, skb->len - 24, mic);
1044 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1045 key->u.aes_cmac.icverrors++;
1046 return RX_DROP_UNUSABLE;
1050 memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1052 /* Remove MMIE */
1053 skb_trim(skb, skb->len - sizeof(*mmie));
1055 return RX_CONTINUE;
1058 ieee80211_rx_result
1059 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1061 struct sk_buff *skb = rx->skb;
1062 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1063 struct ieee80211_key *key = rx->key;
1064 struct ieee80211_mmie_16 *mmie;
1065 u8 aad[20], mic[16], ipn[6];
1066 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1068 if (!ieee80211_is_mgmt(hdr->frame_control))
1069 return RX_CONTINUE;
1071 /* management frames are already linear */
1073 if (skb->len < 24 + sizeof(*mmie))
1074 return RX_DROP_UNUSABLE;
1076 mmie = (struct ieee80211_mmie_16 *)
1077 (skb->data + skb->len - sizeof(*mmie));
1078 if (mmie->element_id != WLAN_EID_MMIE ||
1079 mmie->length != sizeof(*mmie) - 2)
1080 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1082 bip_ipn_swap(ipn, mmie->sequence_number);
1084 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1085 key->u.aes_cmac.replays++;
1086 return RX_DROP_UNUSABLE;
1089 if (!(status->flag & RX_FLAG_DECRYPTED)) {
1090 /* hardware didn't decrypt/verify MIC */
1091 bip_aad(skb, aad);
1092 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1093 skb->data + 24, skb->len - 24, mic);
1094 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1095 key->u.aes_cmac.icverrors++;
1096 return RX_DROP_UNUSABLE;
1100 memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1102 /* Remove MMIE */
1103 skb_trim(skb, skb->len - sizeof(*mmie));
1105 return RX_CONTINUE;
1108 ieee80211_tx_result
1109 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1111 struct sk_buff *skb;
1112 struct ieee80211_tx_info *info;
1113 struct ieee80211_key *key = tx->key;
1114 struct ieee80211_mmie_16 *mmie;
1115 struct ieee80211_hdr *hdr;
1116 u8 aad[20];
1117 u64 pn64;
1118 u8 nonce[12];
1120 if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1121 return TX_DROP;
1123 skb = skb_peek(&tx->skbs);
1125 info = IEEE80211_SKB_CB(skb);
1127 if (info->control.hw_key)
1128 return TX_CONTINUE;
1130 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1131 return TX_DROP;
1133 mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
1134 mmie->element_id = WLAN_EID_MMIE;
1135 mmie->length = sizeof(*mmie) - 2;
1136 mmie->key_id = cpu_to_le16(key->conf.keyidx);
1138 /* PN = PN + 1 */
1139 pn64 = atomic64_inc_return(&key->conf.tx_pn);
1141 bip_ipn_set64(mmie->sequence_number, pn64);
1143 bip_aad(skb, aad);
1145 hdr = (struct ieee80211_hdr *)skb->data;
1146 memcpy(nonce, hdr->addr2, ETH_ALEN);
1147 bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1149 /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1150 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1151 skb->data + 24, skb->len - 24, mmie->mic) < 0)
1152 return TX_DROP;
1154 return TX_CONTINUE;
1157 ieee80211_rx_result
1158 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1160 struct sk_buff *skb = rx->skb;
1161 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1162 struct ieee80211_key *key = rx->key;
1163 struct ieee80211_mmie_16 *mmie;
1164 u8 aad[20], mic[16], ipn[6], nonce[12];
1165 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1167 if (!ieee80211_is_mgmt(hdr->frame_control))
1168 return RX_CONTINUE;
1170 /* management frames are already linear */
1172 if (skb->len < 24 + sizeof(*mmie))
1173 return RX_DROP_UNUSABLE;
1175 mmie = (struct ieee80211_mmie_16 *)
1176 (skb->data + skb->len - sizeof(*mmie));
1177 if (mmie->element_id != WLAN_EID_MMIE ||
1178 mmie->length != sizeof(*mmie) - 2)
1179 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1181 bip_ipn_swap(ipn, mmie->sequence_number);
1183 if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1184 key->u.aes_gmac.replays++;
1185 return RX_DROP_UNUSABLE;
1188 if (!(status->flag & RX_FLAG_DECRYPTED)) {
1189 /* hardware didn't decrypt/verify MIC */
1190 bip_aad(skb, aad);
1192 memcpy(nonce, hdr->addr2, ETH_ALEN);
1193 memcpy(nonce + ETH_ALEN, ipn, 6);
1195 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1196 skb->data + 24, skb->len - 24,
1197 mic) < 0 ||
1198 memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1199 key->u.aes_gmac.icverrors++;
1200 return RX_DROP_UNUSABLE;
1204 memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1206 /* Remove MMIE */
1207 skb_trim(skb, skb->len - sizeof(*mmie));
1209 return RX_CONTINUE;
1212 ieee80211_tx_result
1213 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1215 struct sk_buff *skb;
1216 struct ieee80211_tx_info *info = NULL;
1217 ieee80211_tx_result res;
1219 skb_queue_walk(&tx->skbs, skb) {
1220 info = IEEE80211_SKB_CB(skb);
1222 /* handle hw-only algorithm */
1223 if (!info->control.hw_key)
1224 return TX_DROP;
1226 if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1227 res = ieee80211_crypto_cs_encrypt(tx, skb);
1228 if (res != TX_CONTINUE)
1229 return res;
1233 ieee80211_tx_set_protected(tx);
1235 return TX_CONTINUE;
1238 ieee80211_rx_result
1239 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1241 if (rx->sta && rx->sta->cipher_scheme)
1242 return ieee80211_crypto_cs_decrypt(rx);
1244 return RX_DROP_UNUSABLE;