mac80211: Do not use stack memory with scatterlist for GMAC
[linux/fpc-iii.git] / net / mac80211 / wpa.c
blobe3bb69ba688790b9706ed7205de9f7997d7d3b96
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>
20 #include <crypto/algapi.h>
22 #include "ieee80211_i.h"
23 #include "michael.h"
24 #include "tkip.h"
25 #include "aes_ccm.h"
26 #include "aes_cmac.h"
27 #include "aes_gmac.h"
28 #include "aes_gcm.h"
29 #include "wpa.h"
31 ieee80211_tx_result
32 ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
34 u8 *data, *key, *mic;
35 size_t data_len;
36 unsigned int hdrlen;
37 struct ieee80211_hdr *hdr;
38 struct sk_buff *skb = tx->skb;
39 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
40 int tail;
42 hdr = (struct ieee80211_hdr *)skb->data;
43 if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
44 skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
45 return TX_CONTINUE;
47 hdrlen = ieee80211_hdrlen(hdr->frame_control);
48 if (skb->len < hdrlen)
49 return TX_DROP;
51 data = skb->data + hdrlen;
52 data_len = skb->len - hdrlen;
54 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
55 /* Need to use software crypto for the test */
56 info->control.hw_key = NULL;
59 if (info->control.hw_key &&
60 (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
61 ieee80211_hw_check(&tx->local->hw, SUPPORTS_TX_FRAG)) &&
62 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
63 /* hwaccel - with no need for SW-generated MMIC */
64 return TX_CONTINUE;
67 tail = MICHAEL_MIC_LEN;
68 if (!info->control.hw_key)
69 tail += IEEE80211_TKIP_ICV_LEN;
71 if (WARN(skb_tailroom(skb) < tail ||
72 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN,
73 "mmic: not enough head/tail (%d/%d,%d/%d)\n",
74 skb_headroom(skb), IEEE80211_TKIP_IV_LEN,
75 skb_tailroom(skb), tail))
76 return TX_DROP;
78 key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
79 mic = skb_put(skb, MICHAEL_MIC_LEN);
80 michael_mic(key, hdr, data, data_len, mic);
81 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
82 mic[0]++;
84 return TX_CONTINUE;
88 ieee80211_rx_result
89 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
91 u8 *data, *key = NULL;
92 size_t data_len;
93 unsigned int hdrlen;
94 u8 mic[MICHAEL_MIC_LEN];
95 struct sk_buff *skb = rx->skb;
96 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
97 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
100 * it makes no sense to check for MIC errors on anything other
101 * than data frames.
103 if (!ieee80211_is_data_present(hdr->frame_control))
104 return RX_CONTINUE;
107 * No way to verify the MIC if the hardware stripped it or
108 * the IV with the key index. In this case we have solely rely
109 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
110 * MIC failure report.
112 if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
113 if (status->flag & RX_FLAG_MMIC_ERROR)
114 goto mic_fail_no_key;
116 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
117 rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
118 goto update_iv;
120 return RX_CONTINUE;
124 * Some hardware seems to generate Michael MIC failure reports; even
125 * though, the frame was not encrypted with TKIP and therefore has no
126 * MIC. Ignore the flag them to avoid triggering countermeasures.
128 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
129 !(status->flag & RX_FLAG_DECRYPTED))
130 return RX_CONTINUE;
132 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
134 * APs with pairwise keys should never receive Michael MIC
135 * errors for non-zero keyidx because these are reserved for
136 * group keys and only the AP is sending real multicast
137 * frames in the BSS.
139 return RX_DROP_UNUSABLE;
142 if (status->flag & RX_FLAG_MMIC_ERROR)
143 goto mic_fail;
145 hdrlen = ieee80211_hdrlen(hdr->frame_control);
146 if (skb->len < hdrlen + MICHAEL_MIC_LEN)
147 return RX_DROP_UNUSABLE;
149 if (skb_linearize(rx->skb))
150 return RX_DROP_UNUSABLE;
151 hdr = (void *)skb->data;
153 data = skb->data + hdrlen;
154 data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
155 key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
156 michael_mic(key, hdr, data, data_len, mic);
157 if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN))
158 goto mic_fail;
160 /* remove Michael MIC from payload */
161 skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
163 update_iv:
164 /* update IV in key information to be able to detect replays */
165 rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
166 rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
168 return RX_CONTINUE;
170 mic_fail:
171 rx->key->u.tkip.mic_failures++;
173 mic_fail_no_key:
175 * In some cases the key can be unset - e.g. a multicast packet, in
176 * a driver that supports HW encryption. Send up the key idx only if
177 * the key is set.
179 cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2,
180 is_multicast_ether_addr(hdr->addr1) ?
181 NL80211_KEYTYPE_GROUP :
182 NL80211_KEYTYPE_PAIRWISE,
183 rx->key ? rx->key->conf.keyidx : -1,
184 NULL, GFP_ATOMIC);
185 return RX_DROP_UNUSABLE;
188 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
190 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
191 struct ieee80211_key *key = tx->key;
192 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
193 unsigned int hdrlen;
194 int len, tail;
195 u64 pn;
196 u8 *pos;
198 if (info->control.hw_key &&
199 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
200 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
201 /* hwaccel - with no need for software-generated IV */
202 return 0;
205 hdrlen = ieee80211_hdrlen(hdr->frame_control);
206 len = skb->len - hdrlen;
208 if (info->control.hw_key)
209 tail = 0;
210 else
211 tail = IEEE80211_TKIP_ICV_LEN;
213 if (WARN_ON(skb_tailroom(skb) < tail ||
214 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
215 return -1;
217 pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
218 memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
219 pos += hdrlen;
221 /* the HW only needs room for the IV, but not the actual IV */
222 if (info->control.hw_key &&
223 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
224 return 0;
226 /* Increase IV for the frame */
227 pn = atomic64_inc_return(&key->conf.tx_pn);
228 pos = ieee80211_tkip_add_iv(pos, &key->conf, pn);
230 /* hwaccel - with software IV */
231 if (info->control.hw_key)
232 return 0;
234 /* Add room for ICV */
235 skb_put(skb, IEEE80211_TKIP_ICV_LEN);
237 return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
238 key, skb, pos, len);
242 ieee80211_tx_result
243 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
245 struct sk_buff *skb;
247 ieee80211_tx_set_protected(tx);
249 skb_queue_walk(&tx->skbs, skb) {
250 if (tkip_encrypt_skb(tx, skb) < 0)
251 return TX_DROP;
254 return TX_CONTINUE;
258 ieee80211_rx_result
259 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
261 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
262 int hdrlen, res, hwaccel = 0;
263 struct ieee80211_key *key = rx->key;
264 struct sk_buff *skb = rx->skb;
265 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
267 hdrlen = ieee80211_hdrlen(hdr->frame_control);
269 if (!ieee80211_is_data(hdr->frame_control))
270 return RX_CONTINUE;
272 if (!rx->sta || skb->len - hdrlen < 12)
273 return RX_DROP_UNUSABLE;
275 /* it may be possible to optimize this a bit more */
276 if (skb_linearize(rx->skb))
277 return RX_DROP_UNUSABLE;
278 hdr = (void *)skb->data;
281 * Let TKIP code verify IV, but skip decryption.
282 * In the case where hardware checks the IV as well,
283 * we don't even get here, see ieee80211_rx_h_decrypt()
285 if (status->flag & RX_FLAG_DECRYPTED)
286 hwaccel = 1;
288 res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
289 key, skb->data + hdrlen,
290 skb->len - hdrlen, rx->sta->sta.addr,
291 hdr->addr1, hwaccel, rx->security_idx,
292 &rx->tkip_iv32,
293 &rx->tkip_iv16);
294 if (res != TKIP_DECRYPT_OK)
295 return RX_DROP_UNUSABLE;
297 /* Trim ICV */
298 if (!(status->flag & RX_FLAG_ICV_STRIPPED))
299 skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN);
301 /* Remove IV */
302 memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen);
303 skb_pull(skb, IEEE80211_TKIP_IV_LEN);
305 return RX_CONTINUE;
309 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad)
311 __le16 mask_fc;
312 int a4_included, mgmt;
313 u8 qos_tid;
314 u16 len_a;
315 unsigned int hdrlen;
316 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
319 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
320 * Retry, PwrMgt, MoreData; set Protected
322 mgmt = ieee80211_is_mgmt(hdr->frame_control);
323 mask_fc = hdr->frame_control;
324 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
325 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
326 if (!mgmt)
327 mask_fc &= ~cpu_to_le16(0x0070);
328 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
330 hdrlen = ieee80211_hdrlen(hdr->frame_control);
331 len_a = hdrlen - 2;
332 a4_included = ieee80211_has_a4(hdr->frame_control);
334 if (ieee80211_is_data_qos(hdr->frame_control))
335 qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
336 else
337 qos_tid = 0;
339 /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC
340 * mode authentication are not allowed to collide, yet both are derived
341 * from this vector b_0. We only set L := 1 here to indicate that the
342 * data size can be represented in (L+1) bytes. The CCM layer will take
343 * care of storing the data length in the top (L+1) bytes and setting
344 * and clearing the other bits as is required to derive the two IVs.
346 b_0[0] = 0x1;
348 /* Nonce: Nonce Flags | A2 | PN
349 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
351 b_0[1] = qos_tid | (mgmt << 4);
352 memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
353 memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN);
355 /* AAD (extra authenticate-only data) / masked 802.11 header
356 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
357 put_unaligned_be16(len_a, &aad[0]);
358 put_unaligned(mask_fc, (__le16 *)&aad[2]);
359 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
361 /* Mask Seq#, leave Frag# */
362 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
363 aad[23] = 0;
365 if (a4_included) {
366 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
367 aad[30] = qos_tid;
368 aad[31] = 0;
369 } else {
370 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
371 aad[24] = qos_tid;
376 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
378 hdr[0] = pn[5];
379 hdr[1] = pn[4];
380 hdr[2] = 0;
381 hdr[3] = 0x20 | (key_id << 6);
382 hdr[4] = pn[3];
383 hdr[5] = pn[2];
384 hdr[6] = pn[1];
385 hdr[7] = pn[0];
389 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
391 pn[0] = hdr[7];
392 pn[1] = hdr[6];
393 pn[2] = hdr[5];
394 pn[3] = hdr[4];
395 pn[4] = hdr[1];
396 pn[5] = hdr[0];
400 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
401 unsigned int mic_len)
403 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
404 struct ieee80211_key *key = tx->key;
405 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
406 int hdrlen, len, tail;
407 u8 *pos;
408 u8 pn[6];
409 u64 pn64;
410 u8 aad[CCM_AAD_LEN];
411 u8 b_0[AES_BLOCK_SIZE];
413 if (info->control.hw_key &&
414 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
415 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
416 !((info->control.hw_key->flags &
417 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
418 ieee80211_is_mgmt(hdr->frame_control))) {
420 * hwaccel has no need for preallocated room for CCMP
421 * header or MIC fields
423 return 0;
426 hdrlen = ieee80211_hdrlen(hdr->frame_control);
427 len = skb->len - hdrlen;
429 if (info->control.hw_key)
430 tail = 0;
431 else
432 tail = mic_len;
434 if (WARN_ON(skb_tailroom(skb) < tail ||
435 skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN))
436 return -1;
438 pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN);
439 memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen);
441 /* the HW only needs room for the IV, but not the actual IV */
442 if (info->control.hw_key &&
443 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
444 return 0;
446 hdr = (struct ieee80211_hdr *) pos;
447 pos += hdrlen;
449 pn64 = atomic64_inc_return(&key->conf.tx_pn);
451 pn[5] = pn64;
452 pn[4] = pn64 >> 8;
453 pn[3] = pn64 >> 16;
454 pn[2] = pn64 >> 24;
455 pn[1] = pn64 >> 32;
456 pn[0] = pn64 >> 40;
458 ccmp_pn2hdr(pos, pn, key->conf.keyidx);
460 /* hwaccel - with software CCMP header */
461 if (info->control.hw_key)
462 return 0;
464 pos += IEEE80211_CCMP_HDR_LEN;
465 ccmp_special_blocks(skb, pn, b_0, aad);
466 return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
467 skb_put(skb, mic_len), mic_len);
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 if (status->flag & RX_FLAG_DECRYPTED) {
508 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
509 return RX_DROP_UNUSABLE;
510 if (status->flag & RX_FLAG_MIC_STRIPPED)
511 mic_len = 0;
512 } else {
513 if (skb_linearize(rx->skb))
514 return RX_DROP_UNUSABLE;
517 data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
518 if (!rx->sta || data_len < 0)
519 return RX_DROP_UNUSABLE;
521 if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
522 int res;
524 ccmp_hdr2pn(pn, skb->data + hdrlen);
526 queue = rx->security_idx;
528 res = memcmp(pn, key->u.ccmp.rx_pn[queue],
529 IEEE80211_CCMP_PN_LEN);
530 if (res < 0 ||
531 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
532 key->u.ccmp.replays++;
533 return RX_DROP_UNUSABLE;
536 if (!(status->flag & RX_FLAG_DECRYPTED)) {
537 u8 aad[2 * AES_BLOCK_SIZE];
538 u8 b_0[AES_BLOCK_SIZE];
539 /* hardware didn't decrypt/verify MIC */
540 ccmp_special_blocks(skb, pn, b_0, aad);
542 if (ieee80211_aes_ccm_decrypt(
543 key->u.ccmp.tfm, b_0, aad,
544 skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
545 data_len,
546 skb->data + skb->len - mic_len, mic_len))
547 return RX_DROP_UNUSABLE;
550 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
553 /* Remove CCMP header and MIC */
554 if (pskb_trim(skb, skb->len - mic_len))
555 return RX_DROP_UNUSABLE;
556 memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
557 skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
559 return RX_CONTINUE;
562 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
564 __le16 mask_fc;
565 u8 qos_tid;
566 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
568 memcpy(j_0, hdr->addr2, ETH_ALEN);
569 memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
570 j_0[13] = 0;
571 j_0[14] = 0;
572 j_0[AES_BLOCK_SIZE - 1] = 0x01;
574 /* AAD (extra authenticate-only data) / masked 802.11 header
575 * FC | A1 | A2 | A3 | SC | [A4] | [QC]
577 put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
578 /* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
579 * Retry, PwrMgt, MoreData; set Protected
581 mask_fc = hdr->frame_control;
582 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
583 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
584 if (!ieee80211_is_mgmt(hdr->frame_control))
585 mask_fc &= ~cpu_to_le16(0x0070);
586 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
588 put_unaligned(mask_fc, (__le16 *)&aad[2]);
589 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
591 /* Mask Seq#, leave Frag# */
592 aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
593 aad[23] = 0;
595 if (ieee80211_is_data_qos(hdr->frame_control))
596 qos_tid = *ieee80211_get_qos_ctl(hdr) &
597 IEEE80211_QOS_CTL_TID_MASK;
598 else
599 qos_tid = 0;
601 if (ieee80211_has_a4(hdr->frame_control)) {
602 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
603 aad[30] = qos_tid;
604 aad[31] = 0;
605 } else {
606 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
607 aad[24] = qos_tid;
611 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
613 hdr[0] = pn[5];
614 hdr[1] = pn[4];
615 hdr[2] = 0;
616 hdr[3] = 0x20 | (key_id << 6);
617 hdr[4] = pn[3];
618 hdr[5] = pn[2];
619 hdr[6] = pn[1];
620 hdr[7] = pn[0];
623 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
625 pn[0] = hdr[7];
626 pn[1] = hdr[6];
627 pn[2] = hdr[5];
628 pn[3] = hdr[4];
629 pn[4] = hdr[1];
630 pn[5] = hdr[0];
633 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
635 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
636 struct ieee80211_key *key = tx->key;
637 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
638 int hdrlen, len, tail;
639 u8 *pos;
640 u8 pn[6];
641 u64 pn64;
642 u8 aad[GCM_AAD_LEN];
643 u8 j_0[AES_BLOCK_SIZE];
645 if (info->control.hw_key &&
646 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
647 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
648 !((info->control.hw_key->flags &
649 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
650 ieee80211_is_mgmt(hdr->frame_control))) {
651 /* hwaccel has no need for preallocated room for GCMP
652 * header or MIC fields
654 return 0;
657 hdrlen = ieee80211_hdrlen(hdr->frame_control);
658 len = skb->len - hdrlen;
660 if (info->control.hw_key)
661 tail = 0;
662 else
663 tail = IEEE80211_GCMP_MIC_LEN;
665 if (WARN_ON(skb_tailroom(skb) < tail ||
666 skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
667 return -1;
669 pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
670 memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
671 skb_set_network_header(skb, skb_network_offset(skb) +
672 IEEE80211_GCMP_HDR_LEN);
674 /* the HW only needs room for the IV, but not the actual IV */
675 if (info->control.hw_key &&
676 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
677 return 0;
679 hdr = (struct ieee80211_hdr *)pos;
680 pos += hdrlen;
682 pn64 = atomic64_inc_return(&key->conf.tx_pn);
684 pn[5] = pn64;
685 pn[4] = pn64 >> 8;
686 pn[3] = pn64 >> 16;
687 pn[2] = pn64 >> 24;
688 pn[1] = pn64 >> 32;
689 pn[0] = pn64 >> 40;
691 gcmp_pn2hdr(pos, pn, key->conf.keyidx);
693 /* hwaccel - with software GCMP header */
694 if (info->control.hw_key)
695 return 0;
697 pos += IEEE80211_GCMP_HDR_LEN;
698 gcmp_special_blocks(skb, pn, j_0, aad);
699 return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
700 skb_put(skb, IEEE80211_GCMP_MIC_LEN));
703 ieee80211_tx_result
704 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
706 struct sk_buff *skb;
708 ieee80211_tx_set_protected(tx);
710 skb_queue_walk(&tx->skbs, skb) {
711 if (gcmp_encrypt_skb(tx, skb) < 0)
712 return TX_DROP;
715 return TX_CONTINUE;
718 ieee80211_rx_result
719 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
721 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
722 int hdrlen;
723 struct ieee80211_key *key = rx->key;
724 struct sk_buff *skb = rx->skb;
725 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
726 u8 pn[IEEE80211_GCMP_PN_LEN];
727 int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN;
729 hdrlen = ieee80211_hdrlen(hdr->frame_control);
731 if (!ieee80211_is_data(hdr->frame_control) &&
732 !ieee80211_is_robust_mgmt_frame(skb))
733 return RX_CONTINUE;
735 if (status->flag & RX_FLAG_DECRYPTED) {
736 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
737 return RX_DROP_UNUSABLE;
738 if (status->flag & RX_FLAG_MIC_STRIPPED)
739 mic_len = 0;
740 } else {
741 if (skb_linearize(rx->skb))
742 return RX_DROP_UNUSABLE;
745 data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
746 if (!rx->sta || data_len < 0)
747 return RX_DROP_UNUSABLE;
749 if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
750 int res;
752 gcmp_hdr2pn(pn, skb->data + hdrlen);
754 queue = rx->security_idx;
756 res = memcmp(pn, key->u.gcmp.rx_pn[queue],
757 IEEE80211_GCMP_PN_LEN);
758 if (res < 0 ||
759 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
760 key->u.gcmp.replays++;
761 return RX_DROP_UNUSABLE;
764 if (!(status->flag & RX_FLAG_DECRYPTED)) {
765 u8 aad[2 * AES_BLOCK_SIZE];
766 u8 j_0[AES_BLOCK_SIZE];
767 /* hardware didn't decrypt/verify MIC */
768 gcmp_special_blocks(skb, pn, j_0, aad);
770 if (ieee80211_aes_gcm_decrypt(
771 key->u.gcmp.tfm, j_0, aad,
772 skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
773 data_len,
774 skb->data + skb->len -
775 IEEE80211_GCMP_MIC_LEN))
776 return RX_DROP_UNUSABLE;
779 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
782 /* Remove GCMP header and MIC */
783 if (pskb_trim(skb, skb->len - mic_len))
784 return RX_DROP_UNUSABLE;
785 memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
786 skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
788 return RX_CONTINUE;
791 static ieee80211_tx_result
792 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
793 struct sk_buff *skb)
795 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
796 struct ieee80211_key *key = tx->key;
797 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
798 int hdrlen;
799 u8 *pos, iv_len = key->conf.iv_len;
801 if (info->control.hw_key &&
802 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
803 /* hwaccel has no need for preallocated head room */
804 return TX_CONTINUE;
807 if (unlikely(skb_headroom(skb) < iv_len &&
808 pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
809 return TX_DROP;
811 hdrlen = ieee80211_hdrlen(hdr->frame_control);
813 pos = skb_push(skb, iv_len);
814 memmove(pos, pos + iv_len, hdrlen);
816 return TX_CONTINUE;
819 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
821 int i;
823 /* pn is little endian */
824 for (i = len - 1; i >= 0; i--) {
825 if (pn1[i] < pn2[i])
826 return -1;
827 else if (pn1[i] > pn2[i])
828 return 1;
831 return 0;
834 static ieee80211_rx_result
835 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
837 struct ieee80211_key *key = rx->key;
838 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
839 const struct ieee80211_cipher_scheme *cs = NULL;
840 int hdrlen = ieee80211_hdrlen(hdr->frame_control);
841 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
842 int data_len;
843 u8 *rx_pn;
844 u8 *skb_pn;
845 u8 qos_tid;
847 if (!rx->sta || !rx->sta->cipher_scheme ||
848 !(status->flag & RX_FLAG_DECRYPTED))
849 return RX_DROP_UNUSABLE;
851 if (!ieee80211_is_data(hdr->frame_control))
852 return RX_CONTINUE;
854 cs = rx->sta->cipher_scheme;
856 data_len = rx->skb->len - hdrlen - cs->hdr_len;
858 if (data_len < 0)
859 return RX_DROP_UNUSABLE;
861 if (ieee80211_is_data_qos(hdr->frame_control))
862 qos_tid = *ieee80211_get_qos_ctl(hdr) &
863 IEEE80211_QOS_CTL_TID_MASK;
864 else
865 qos_tid = 0;
867 if (skb_linearize(rx->skb))
868 return RX_DROP_UNUSABLE;
870 hdr = (struct ieee80211_hdr *)rx->skb->data;
872 rx_pn = key->u.gen.rx_pn[qos_tid];
873 skb_pn = rx->skb->data + hdrlen + cs->pn_off;
875 if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
876 return RX_DROP_UNUSABLE;
878 memcpy(rx_pn, skb_pn, cs->pn_len);
880 /* remove security header and MIC */
881 if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
882 return RX_DROP_UNUSABLE;
884 memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
885 skb_pull(rx->skb, cs->hdr_len);
887 return RX_CONTINUE;
890 static void bip_aad(struct sk_buff *skb, u8 *aad)
892 __le16 mask_fc;
893 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
895 /* BIP AAD: FC(masked) || A1 || A2 || A3 */
897 /* FC type/subtype */
898 /* Mask FC Retry, PwrMgt, MoreData flags to zero */
899 mask_fc = hdr->frame_control;
900 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
901 IEEE80211_FCTL_MOREDATA);
902 put_unaligned(mask_fc, (__le16 *) &aad[0]);
903 /* A1 || A2 || A3 */
904 memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
908 static inline void bip_ipn_set64(u8 *d, u64 pn)
910 *d++ = pn;
911 *d++ = pn >> 8;
912 *d++ = pn >> 16;
913 *d++ = pn >> 24;
914 *d++ = pn >> 32;
915 *d = pn >> 40;
918 static inline void bip_ipn_swap(u8 *d, const u8 *s)
920 *d++ = s[5];
921 *d++ = s[4];
922 *d++ = s[3];
923 *d++ = s[2];
924 *d++ = s[1];
925 *d = s[0];
929 ieee80211_tx_result
930 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
932 struct sk_buff *skb;
933 struct ieee80211_tx_info *info;
934 struct ieee80211_key *key = tx->key;
935 struct ieee80211_mmie *mmie;
936 u8 aad[20];
937 u64 pn64;
939 if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
940 return TX_DROP;
942 skb = skb_peek(&tx->skbs);
944 info = IEEE80211_SKB_CB(skb);
946 if (info->control.hw_key)
947 return TX_CONTINUE;
949 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
950 return TX_DROP;
952 mmie = skb_put(skb, sizeof(*mmie));
953 mmie->element_id = WLAN_EID_MMIE;
954 mmie->length = sizeof(*mmie) - 2;
955 mmie->key_id = cpu_to_le16(key->conf.keyidx);
957 /* PN = PN + 1 */
958 pn64 = atomic64_inc_return(&key->conf.tx_pn);
960 bip_ipn_set64(mmie->sequence_number, pn64);
962 bip_aad(skb, aad);
965 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
967 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
968 skb->data + 24, skb->len - 24, mmie->mic);
970 return TX_CONTINUE;
973 ieee80211_tx_result
974 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
976 struct sk_buff *skb;
977 struct ieee80211_tx_info *info;
978 struct ieee80211_key *key = tx->key;
979 struct ieee80211_mmie_16 *mmie;
980 u8 aad[20];
981 u64 pn64;
983 if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
984 return TX_DROP;
986 skb = skb_peek(&tx->skbs);
988 info = IEEE80211_SKB_CB(skb);
990 if (info->control.hw_key)
991 return TX_CONTINUE;
993 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
994 return TX_DROP;
996 mmie = skb_put(skb, sizeof(*mmie));
997 mmie->element_id = WLAN_EID_MMIE;
998 mmie->length = sizeof(*mmie) - 2;
999 mmie->key_id = cpu_to_le16(key->conf.keyidx);
1001 /* PN = PN + 1 */
1002 pn64 = atomic64_inc_return(&key->conf.tx_pn);
1004 bip_ipn_set64(mmie->sequence_number, pn64);
1006 bip_aad(skb, aad);
1008 /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1010 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1011 skb->data + 24, skb->len - 24, mmie->mic);
1013 return TX_CONTINUE;
1016 ieee80211_rx_result
1017 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1019 struct sk_buff *skb = rx->skb;
1020 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1021 struct ieee80211_key *key = rx->key;
1022 struct ieee80211_mmie *mmie;
1023 u8 aad[20], mic[8], ipn[6];
1024 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1026 if (!ieee80211_is_mgmt(hdr->frame_control))
1027 return RX_CONTINUE;
1029 /* management frames are already linear */
1031 if (skb->len < 24 + sizeof(*mmie))
1032 return RX_DROP_UNUSABLE;
1034 mmie = (struct ieee80211_mmie *)
1035 (skb->data + skb->len - sizeof(*mmie));
1036 if (mmie->element_id != WLAN_EID_MMIE ||
1037 mmie->length != sizeof(*mmie) - 2)
1038 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1040 bip_ipn_swap(ipn, mmie->sequence_number);
1042 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1043 key->u.aes_cmac.replays++;
1044 return RX_DROP_UNUSABLE;
1047 if (!(status->flag & RX_FLAG_DECRYPTED)) {
1048 /* hardware didn't decrypt/verify MIC */
1049 bip_aad(skb, aad);
1050 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1051 skb->data + 24, skb->len - 24, mic);
1052 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1053 key->u.aes_cmac.icverrors++;
1054 return RX_DROP_UNUSABLE;
1058 memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1060 /* Remove MMIE */
1061 skb_trim(skb, skb->len - sizeof(*mmie));
1063 return RX_CONTINUE;
1066 ieee80211_rx_result
1067 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1069 struct sk_buff *skb = rx->skb;
1070 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1071 struct ieee80211_key *key = rx->key;
1072 struct ieee80211_mmie_16 *mmie;
1073 u8 aad[20], mic[16], ipn[6];
1074 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1076 if (!ieee80211_is_mgmt(hdr->frame_control))
1077 return RX_CONTINUE;
1079 /* management frames are already linear */
1081 if (skb->len < 24 + sizeof(*mmie))
1082 return RX_DROP_UNUSABLE;
1084 mmie = (struct ieee80211_mmie_16 *)
1085 (skb->data + skb->len - sizeof(*mmie));
1086 if (mmie->element_id != WLAN_EID_MMIE ||
1087 mmie->length != sizeof(*mmie) - 2)
1088 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1090 bip_ipn_swap(ipn, mmie->sequence_number);
1092 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1093 key->u.aes_cmac.replays++;
1094 return RX_DROP_UNUSABLE;
1097 if (!(status->flag & RX_FLAG_DECRYPTED)) {
1098 /* hardware didn't decrypt/verify MIC */
1099 bip_aad(skb, aad);
1100 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1101 skb->data + 24, skb->len - 24, mic);
1102 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1103 key->u.aes_cmac.icverrors++;
1104 return RX_DROP_UNUSABLE;
1108 memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1110 /* Remove MMIE */
1111 skb_trim(skb, skb->len - sizeof(*mmie));
1113 return RX_CONTINUE;
1116 ieee80211_tx_result
1117 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1119 struct sk_buff *skb;
1120 struct ieee80211_tx_info *info;
1121 struct ieee80211_key *key = tx->key;
1122 struct ieee80211_mmie_16 *mmie;
1123 struct ieee80211_hdr *hdr;
1124 u8 aad[GMAC_AAD_LEN];
1125 u64 pn64;
1126 u8 nonce[GMAC_NONCE_LEN];
1128 if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1129 return TX_DROP;
1131 skb = skb_peek(&tx->skbs);
1133 info = IEEE80211_SKB_CB(skb);
1135 if (info->control.hw_key)
1136 return TX_CONTINUE;
1138 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1139 return TX_DROP;
1141 mmie = skb_put(skb, sizeof(*mmie));
1142 mmie->element_id = WLAN_EID_MMIE;
1143 mmie->length = sizeof(*mmie) - 2;
1144 mmie->key_id = cpu_to_le16(key->conf.keyidx);
1146 /* PN = PN + 1 */
1147 pn64 = atomic64_inc_return(&key->conf.tx_pn);
1149 bip_ipn_set64(mmie->sequence_number, pn64);
1151 bip_aad(skb, aad);
1153 hdr = (struct ieee80211_hdr *)skb->data;
1154 memcpy(nonce, hdr->addr2, ETH_ALEN);
1155 bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1157 /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1158 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1159 skb->data + 24, skb->len - 24, mmie->mic) < 0)
1160 return TX_DROP;
1162 return TX_CONTINUE;
1165 ieee80211_rx_result
1166 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1168 struct sk_buff *skb = rx->skb;
1169 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1170 struct ieee80211_key *key = rx->key;
1171 struct ieee80211_mmie_16 *mmie;
1172 u8 aad[GMAC_AAD_LEN], *mic, ipn[6], nonce[GMAC_NONCE_LEN];
1173 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1175 if (!ieee80211_is_mgmt(hdr->frame_control))
1176 return RX_CONTINUE;
1178 /* management frames are already linear */
1180 if (skb->len < 24 + sizeof(*mmie))
1181 return RX_DROP_UNUSABLE;
1183 mmie = (struct ieee80211_mmie_16 *)
1184 (skb->data + skb->len - sizeof(*mmie));
1185 if (mmie->element_id != WLAN_EID_MMIE ||
1186 mmie->length != sizeof(*mmie) - 2)
1187 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1189 bip_ipn_swap(ipn, mmie->sequence_number);
1191 if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1192 key->u.aes_gmac.replays++;
1193 return RX_DROP_UNUSABLE;
1196 if (!(status->flag & RX_FLAG_DECRYPTED)) {
1197 /* hardware didn't decrypt/verify MIC */
1198 bip_aad(skb, aad);
1200 memcpy(nonce, hdr->addr2, ETH_ALEN);
1201 memcpy(nonce + ETH_ALEN, ipn, 6);
1203 mic = kmalloc(GMAC_MIC_LEN, GFP_ATOMIC);
1204 if (!mic)
1205 return RX_DROP_UNUSABLE;
1206 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1207 skb->data + 24, skb->len - 24,
1208 mic) < 0 ||
1209 crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1210 key->u.aes_gmac.icverrors++;
1211 kfree(mic);
1212 return RX_DROP_UNUSABLE;
1214 kfree(mic);
1217 memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1219 /* Remove MMIE */
1220 skb_trim(skb, skb->len - sizeof(*mmie));
1222 return RX_CONTINUE;
1225 ieee80211_tx_result
1226 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1228 struct sk_buff *skb;
1229 struct ieee80211_tx_info *info = NULL;
1230 ieee80211_tx_result res;
1232 skb_queue_walk(&tx->skbs, skb) {
1233 info = IEEE80211_SKB_CB(skb);
1235 /* handle hw-only algorithm */
1236 if (!info->control.hw_key)
1237 return TX_DROP;
1239 if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1240 res = ieee80211_crypto_cs_encrypt(tx, skb);
1241 if (res != TX_CONTINUE)
1242 return res;
1246 ieee80211_tx_set_protected(tx);
1248 return TX_CONTINUE;
1251 ieee80211_rx_result
1252 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1254 if (rx->sta && rx->sta->cipher_scheme)
1255 return ieee80211_crypto_cs_decrypt(rx);
1257 return RX_DROP_UNUSABLE;