2 * Copyright 2002-2004, Instant802 Networks, Inc.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
9 #include <linux/netdevice.h>
10 #include <linux/types.h>
11 #include <linux/slab.h>
12 #include <linux/skbuff.h>
13 #include <linux/compiler.h>
14 #include <net/mac80211.h>
16 #include "ieee80211_i.h"
22 static int ieee80211_get_hdr_info(const struct sk_buff
*skb
, u8
**sa
, u8
**da
,
23 u8
*qos_tid
, u8
**data
, size_t *data_len
)
25 struct ieee80211_hdr
*hdr
;
31 hdr
= (struct ieee80211_hdr
*) skb
->data
;
32 fc
= le16_to_cpu(hdr
->frame_control
);
35 if ((fc
& (IEEE80211_FCTL_FROMDS
| IEEE80211_FCTL_TODS
)) ==
36 (IEEE80211_FCTL_FROMDS
| IEEE80211_FCTL_TODS
)) {
40 } else if (fc
& IEEE80211_FCTL_FROMDS
) {
43 } else if (fc
& IEEE80211_FCTL_TODS
) {
54 *data
= skb
->data
+ hdrlen
;
55 *data_len
= skb
->len
- hdrlen
;
57 a4_included
= (fc
& (IEEE80211_FCTL_TODS
| IEEE80211_FCTL_FROMDS
)) ==
58 (IEEE80211_FCTL_TODS
| IEEE80211_FCTL_FROMDS
);
59 if ((fc
& IEEE80211_FCTL_FTYPE
) == IEEE80211_FTYPE_DATA
&&
60 fc
& IEEE80211_STYPE_QOS_DATA
) {
61 pos
= (u8
*) &hdr
->addr4
;
64 *qos_tid
= pos
[0] & 0x0f;
65 *qos_tid
|= 0x80; /* qos_included flag */
69 return skb
->len
< hdrlen
? -1 : 0;
74 ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data
*tx
)
76 u8
*data
, *sa
, *da
, *key
, *mic
, qos_tid
;
79 struct sk_buff
*skb
= tx
->skb
;
85 if (!tx
->key
|| tx
->key
->conf
.alg
!= ALG_TKIP
|| skb
->len
< 24 ||
86 !WLAN_FC_DATA_PRESENT(fc
))
89 if (ieee80211_get_hdr_info(skb
, &sa
, &da
, &qos_tid
, &data
, &data_len
))
92 if ((tx
->key
->flags
& KEY_FLAG_UPLOADED_TO_HARDWARE
) &&
93 !(tx
->flags
& IEEE80211_TX_FRAGMENTED
) &&
94 !(tx
->key
->conf
.flags
& IEEE80211_KEY_FLAG_GENERATE_MMIC
) &&
96 /* hwaccel - with no need for preallocated room for Michael MIC
101 if (skb_tailroom(skb
) < MICHAEL_MIC_LEN
) {
102 I802_DEBUG_INC(tx
->local
->tx_expand_skb_head
);
103 if (unlikely(pskb_expand_head(skb
, TKIP_IV_LEN
,
104 MICHAEL_MIC_LEN
+ TKIP_ICV_LEN
,
106 printk(KERN_DEBUG
"%s: failed to allocate more memory "
107 "for Michael MIC\n", tx
->dev
->name
);
113 authenticator
= fc
& IEEE80211_FCTL_FROMDS
; /* FIX */
117 key
= &tx
->key
->conf
.key
[authenticator
? ALG_TKIP_TEMP_AUTH_TX_MIC_KEY
:
118 ALG_TKIP_TEMP_AUTH_RX_MIC_KEY
];
119 mic
= skb_put(skb
, MICHAEL_MIC_LEN
);
120 michael_mic(key
, da
, sa
, qos_tid
& 0x0f, data
, data_len
, mic
);
127 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data
*rx
)
129 u8
*data
, *sa
, *da
, *key
= NULL
, qos_tid
;
132 u8 mic
[MICHAEL_MIC_LEN
];
133 struct sk_buff
*skb
= rx
->skb
;
134 int authenticator
= 1, wpa_test
= 0;
135 DECLARE_MAC_BUF(mac
);
140 * No way to verify the MIC if the hardware stripped it
142 if (rx
->status
->flag
& RX_FLAG_MMIC_STRIPPED
)
145 if (!rx
->key
|| rx
->key
->conf
.alg
!= ALG_TKIP
||
146 !(rx
->fc
& IEEE80211_FCTL_PROTECTED
) || !WLAN_FC_DATA_PRESENT(fc
))
149 if (ieee80211_get_hdr_info(skb
, &sa
, &da
, &qos_tid
, &data
, &data_len
)
150 || data_len
< MICHAEL_MIC_LEN
)
151 return RX_DROP_UNUSABLE
;
153 data_len
-= MICHAEL_MIC_LEN
;
156 authenticator
= fc
& IEEE80211_FCTL_TODS
; /* FIX */
160 key
= &rx
->key
->conf
.key
[authenticator
? ALG_TKIP_TEMP_AUTH_RX_MIC_KEY
:
161 ALG_TKIP_TEMP_AUTH_TX_MIC_KEY
];
162 michael_mic(key
, da
, sa
, qos_tid
& 0x0f, data
, data_len
, mic
);
163 if (memcmp(mic
, data
+ data_len
, MICHAEL_MIC_LEN
) != 0 || wpa_test
) {
164 if (!(rx
->flags
& IEEE80211_RX_RA_MATCH
))
165 return RX_DROP_UNUSABLE
;
167 printk(KERN_DEBUG
"%s: invalid Michael MIC in data frame from "
168 "%s\n", rx
->dev
->name
, print_mac(mac
, sa
));
170 mac80211_ev_michael_mic_failure(rx
->dev
, rx
->key
->conf
.keyidx
,
172 return RX_DROP_UNUSABLE
;
175 /* remove Michael MIC from payload */
176 skb_trim(skb
, skb
->len
- MICHAEL_MIC_LEN
);
178 /* update IV in key information to be able to detect replays */
179 rx
->key
->u
.tkip
.rx
[rx
->queue
].iv32
= rx
->tkip_iv32
;
180 rx
->key
->u
.tkip
.rx
[rx
->queue
].iv16
= rx
->tkip_iv16
;
186 static int tkip_encrypt_skb(struct ieee80211_tx_data
*tx
, struct sk_buff
*skb
)
188 struct ieee80211_hdr
*hdr
= (struct ieee80211_hdr
*) skb
->data
;
189 struct ieee80211_key
*key
= tx
->key
;
190 struct ieee80211_tx_info
*info
= IEEE80211_SKB_CB(skb
);
191 int hdrlen
, len
, tailneed
;
195 info
->control
.icv_len
= TKIP_ICV_LEN
;
196 info
->control
.iv_len
= TKIP_IV_LEN
;
198 if ((tx
->key
->flags
& KEY_FLAG_UPLOADED_TO_HARDWARE
) &&
199 !(tx
->key
->conf
.flags
& IEEE80211_KEY_FLAG_GENERATE_IV
)) {
200 /* hwaccel - with no need for preallocated room for IV/ICV */
201 info
->control
.hw_key
= &tx
->key
->conf
;
205 fc
= le16_to_cpu(hdr
->frame_control
);
206 hdrlen
= ieee80211_get_hdrlen(fc
);
207 len
= skb
->len
- hdrlen
;
209 if (tx
->key
->flags
& KEY_FLAG_UPLOADED_TO_HARDWARE
)
212 tailneed
= TKIP_ICV_LEN
;
214 if ((skb_headroom(skb
) < TKIP_IV_LEN
||
215 skb_tailroom(skb
) < tailneed
)) {
216 I802_DEBUG_INC(tx
->local
->tx_expand_skb_head
);
217 if (unlikely(pskb_expand_head(skb
, TKIP_IV_LEN
, tailneed
,
222 pos
= skb_push(skb
, TKIP_IV_LEN
);
223 memmove(pos
, pos
+ TKIP_IV_LEN
, hdrlen
);
226 /* Increase IV for the frame */
227 key
->u
.tkip
.tx
.iv16
++;
228 if (key
->u
.tkip
.tx
.iv16
== 0)
229 key
->u
.tkip
.tx
.iv32
++;
231 if (tx
->key
->flags
& KEY_FLAG_UPLOADED_TO_HARDWARE
) {
232 hdr
= (struct ieee80211_hdr
*)skb
->data
;
234 /* hwaccel - with preallocated room for IV */
235 ieee80211_tkip_add_iv(pos
, key
,
236 (u8
) (key
->u
.tkip
.tx
.iv16
>> 8),
237 (u8
) (((key
->u
.tkip
.tx
.iv16
>> 8) | 0x20) &
239 (u8
) key
->u
.tkip
.tx
.iv16
);
241 info
->control
.hw_key
= &tx
->key
->conf
;
245 /* Add room for ICV */
246 skb_put(skb
, TKIP_ICV_LEN
);
248 hdr
= (struct ieee80211_hdr
*) skb
->data
;
249 ieee80211_tkip_encrypt_data(tx
->local
->wep_tx_tfm
,
250 key
, pos
, len
, hdr
->addr2
);
256 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data
*tx
)
258 struct sk_buff
*skb
= tx
->skb
;
260 ieee80211_tx_set_protected(tx
);
262 if (tkip_encrypt_skb(tx
, skb
) < 0)
265 if (tx
->extra_frag
) {
267 for (i
= 0; i
< tx
->num_extra_frag
; i
++) {
268 if (tkip_encrypt_skb(tx
, tx
->extra_frag
[i
]) < 0)
278 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data
*rx
)
280 struct ieee80211_hdr
*hdr
= (struct ieee80211_hdr
*) rx
->skb
->data
;
282 int hdrlen
, res
, hwaccel
= 0, wpa_test
= 0;
283 struct ieee80211_key
*key
= rx
->key
;
284 struct sk_buff
*skb
= rx
->skb
;
285 DECLARE_MAC_BUF(mac
);
287 fc
= le16_to_cpu(hdr
->frame_control
);
288 hdrlen
= ieee80211_get_hdrlen(fc
);
290 if ((rx
->fc
& IEEE80211_FCTL_FTYPE
) != IEEE80211_FTYPE_DATA
)
293 if (!rx
->sta
|| skb
->len
- hdrlen
< 12)
294 return RX_DROP_UNUSABLE
;
296 if (rx
->status
->flag
& RX_FLAG_DECRYPTED
) {
297 if (rx
->status
->flag
& RX_FLAG_IV_STRIPPED
) {
299 * Hardware took care of all processing, including
300 * replay protection, and stripped the ICV/IV so
301 * we cannot do any checks here.
306 /* let TKIP code verify IV, but skip decryption */
310 res
= ieee80211_tkip_decrypt_data(rx
->local
->wep_rx_tfm
,
311 key
, skb
->data
+ hdrlen
,
312 skb
->len
- hdrlen
, rx
->sta
->addr
,
313 hdr
->addr1
, hwaccel
, rx
->queue
,
316 if (res
!= TKIP_DECRYPT_OK
|| wpa_test
) {
317 #ifdef CONFIG_MAC80211_DEBUG
319 printk(KERN_DEBUG
"%s: TKIP decrypt failed for RX "
320 "frame from %s (res=%d)\n", rx
->dev
->name
,
321 print_mac(mac
, rx
->sta
->addr
), res
);
322 #endif /* CONFIG_MAC80211_DEBUG */
323 return RX_DROP_UNUSABLE
;
327 skb_trim(skb
, skb
->len
- TKIP_ICV_LEN
);
330 memmove(skb
->data
+ TKIP_IV_LEN
, skb
->data
, hdrlen
);
331 skb_pull(skb
, TKIP_IV_LEN
);
337 static void ccmp_special_blocks(struct sk_buff
*skb
, u8
*pn
, u8
*b_0
, u8
*aad
,
341 int a4_included
, qos_included
;
342 u8 qos_tid
, *fc_pos
, *data
, *sa
, *da
;
345 struct ieee80211_hdr
*hdr
= (struct ieee80211_hdr
*) skb
->data
;
347 fc_pos
= (u8
*) &hdr
->frame_control
;
348 fc
= fc_pos
[0] ^ (fc_pos
[1] << 8);
349 a4_included
= (fc
& (IEEE80211_FCTL_TODS
| IEEE80211_FCTL_FROMDS
)) ==
350 (IEEE80211_FCTL_TODS
| IEEE80211_FCTL_FROMDS
);
352 ieee80211_get_hdr_info(skb
, &sa
, &da
, &qos_tid
, &data
, &data_len
);
353 data_len
-= CCMP_HDR_LEN
+ (encrypted
? CCMP_MIC_LEN
: 0);
354 if (qos_tid
& 0x80) {
359 /* First block, b_0 */
361 b_0
[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
362 /* Nonce: QoS Priority | A2 | PN */
364 memcpy(&b_0
[2], hdr
->addr2
, 6);
365 memcpy(&b_0
[8], pn
, CCMP_PN_LEN
);
367 b_0
[14] = (data_len
>> 8) & 0xff;
368 b_0
[15] = data_len
& 0xff;
371 /* AAD (extra authenticate-only data) / masked 802.11 header
372 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
374 len_a
= a4_included
? 28 : 22;
378 aad
[0] = 0; /* (len_a >> 8) & 0xff; */
379 aad
[1] = len_a
& 0xff;
380 /* Mask FC: zero subtype b4 b5 b6 */
381 aad
[2] = fc_pos
[0] & ~(BIT(4) | BIT(5) | BIT(6));
382 /* Retry, PwrMgt, MoreData; set Protected */
383 aad
[3] = (fc_pos
[1] & ~(BIT(3) | BIT(4) | BIT(5))) | BIT(6);
384 memcpy(&aad
[4], &hdr
->addr1
, 18);
386 /* Mask Seq#, leave Frag# */
387 aad
[22] = *((u8
*) &hdr
->seq_ctrl
) & 0x0f;
390 memcpy(&aad
[24], hdr
->addr4
, 6);
394 memset(&aad
[24], 0, 8);
396 u8
*dpos
= &aad
[a4_included
? 30 : 24];
398 /* Mask QoS Control field */
405 static inline void ccmp_pn2hdr(u8
*hdr
, u8
*pn
, int key_id
)
410 hdr
[3] = 0x20 | (key_id
<< 6);
418 static inline int ccmp_hdr2pn(u8
*pn
, u8
*hdr
)
426 return (hdr
[3] >> 6) & 0x03;
430 static int ccmp_encrypt_skb(struct ieee80211_tx_data
*tx
, struct sk_buff
*skb
)
432 struct ieee80211_hdr
*hdr
= (struct ieee80211_hdr
*) skb
->data
;
433 struct ieee80211_key
*key
= tx
->key
;
434 struct ieee80211_tx_info
*info
= IEEE80211_SKB_CB(skb
);
435 int hdrlen
, len
, tailneed
;
437 u8
*pos
, *pn
, *b_0
, *aad
, *scratch
;
440 info
->control
.icv_len
= CCMP_MIC_LEN
;
441 info
->control
.iv_len
= CCMP_HDR_LEN
;
443 if ((tx
->key
->flags
& KEY_FLAG_UPLOADED_TO_HARDWARE
) &&
444 !(tx
->key
->conf
.flags
& IEEE80211_KEY_FLAG_GENERATE_IV
)) {
445 /* hwaccel - with no need for preallocated room for CCMP "
446 * header or MIC fields */
447 info
->control
.hw_key
= &tx
->key
->conf
;
451 scratch
= key
->u
.ccmp
.tx_crypto_buf
;
452 b_0
= scratch
+ 3 * AES_BLOCK_LEN
;
453 aad
= scratch
+ 4 * AES_BLOCK_LEN
;
455 fc
= le16_to_cpu(hdr
->frame_control
);
456 hdrlen
= ieee80211_get_hdrlen(fc
);
457 len
= skb
->len
- hdrlen
;
459 if (key
->flags
& KEY_FLAG_UPLOADED_TO_HARDWARE
)
462 tailneed
= CCMP_MIC_LEN
;
464 if ((skb_headroom(skb
) < CCMP_HDR_LEN
||
465 skb_tailroom(skb
) < tailneed
)) {
466 I802_DEBUG_INC(tx
->local
->tx_expand_skb_head
);
467 if (unlikely(pskb_expand_head(skb
, CCMP_HDR_LEN
, tailneed
,
472 pos
= skb_push(skb
, CCMP_HDR_LEN
);
473 memmove(pos
, pos
+ CCMP_HDR_LEN
, hdrlen
);
474 hdr
= (struct ieee80211_hdr
*) pos
;
478 pn
= key
->u
.ccmp
.tx_pn
;
480 for (i
= CCMP_PN_LEN
- 1; i
>= 0; i
--) {
486 ccmp_pn2hdr(pos
, pn
, key
->conf
.keyidx
);
488 if (key
->flags
& KEY_FLAG_UPLOADED_TO_HARDWARE
) {
489 /* hwaccel - with preallocated room for CCMP header */
490 info
->control
.hw_key
= &tx
->key
->conf
;
495 ccmp_special_blocks(skb
, pn
, b_0
, aad
, 0);
496 ieee80211_aes_ccm_encrypt(key
->u
.ccmp
.tfm
, scratch
, b_0
, aad
, pos
, len
,
497 pos
, skb_put(skb
, CCMP_MIC_LEN
));
504 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data
*tx
)
506 struct sk_buff
*skb
= tx
->skb
;
508 ieee80211_tx_set_protected(tx
);
510 if (ccmp_encrypt_skb(tx
, skb
) < 0)
513 if (tx
->extra_frag
) {
515 for (i
= 0; i
< tx
->num_extra_frag
; i
++) {
516 if (ccmp_encrypt_skb(tx
, tx
->extra_frag
[i
]) < 0)
526 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data
*rx
)
528 struct ieee80211_hdr
*hdr
= (struct ieee80211_hdr
*) rx
->skb
->data
;
531 struct ieee80211_key
*key
= rx
->key
;
532 struct sk_buff
*skb
= rx
->skb
;
535 DECLARE_MAC_BUF(mac
);
537 fc
= le16_to_cpu(hdr
->frame_control
);
538 hdrlen
= ieee80211_get_hdrlen(fc
);
540 if ((rx
->fc
& IEEE80211_FCTL_FTYPE
) != IEEE80211_FTYPE_DATA
)
543 data_len
= skb
->len
- hdrlen
- CCMP_HDR_LEN
- CCMP_MIC_LEN
;
544 if (!rx
->sta
|| data_len
< 0)
545 return RX_DROP_UNUSABLE
;
547 if ((rx
->status
->flag
& RX_FLAG_DECRYPTED
) &&
548 (rx
->status
->flag
& RX_FLAG_IV_STRIPPED
))
551 (void) ccmp_hdr2pn(pn
, skb
->data
+ hdrlen
);
553 if (memcmp(pn
, key
->u
.ccmp
.rx_pn
[rx
->queue
], CCMP_PN_LEN
) <= 0) {
554 #ifdef CONFIG_MAC80211_DEBUG
555 u8
*ppn
= key
->u
.ccmp
.rx_pn
[rx
->queue
];
557 printk(KERN_DEBUG
"%s: CCMP replay detected for RX frame from "
558 "%s (RX PN %02x%02x%02x%02x%02x%02x <= prev. PN "
559 "%02x%02x%02x%02x%02x%02x)\n", rx
->dev
->name
,
560 print_mac(mac
, rx
->sta
->addr
),
561 pn
[0], pn
[1], pn
[2], pn
[3], pn
[4], pn
[5],
562 ppn
[0], ppn
[1], ppn
[2], ppn
[3], ppn
[4], ppn
[5]);
563 #endif /* CONFIG_MAC80211_DEBUG */
564 key
->u
.ccmp
.replays
++;
565 return RX_DROP_UNUSABLE
;
568 if (!(rx
->status
->flag
& RX_FLAG_DECRYPTED
)) {
569 /* hardware didn't decrypt/verify MIC */
570 u8
*scratch
, *b_0
, *aad
;
572 scratch
= key
->u
.ccmp
.rx_crypto_buf
;
573 b_0
= scratch
+ 3 * AES_BLOCK_LEN
;
574 aad
= scratch
+ 4 * AES_BLOCK_LEN
;
576 ccmp_special_blocks(skb
, pn
, b_0
, aad
, 1);
578 if (ieee80211_aes_ccm_decrypt(
579 key
->u
.ccmp
.tfm
, scratch
, b_0
, aad
,
580 skb
->data
+ hdrlen
+ CCMP_HDR_LEN
, data_len
,
581 skb
->data
+ skb
->len
- CCMP_MIC_LEN
,
582 skb
->data
+ hdrlen
+ CCMP_HDR_LEN
)) {
583 #ifdef CONFIG_MAC80211_DEBUG
585 printk(KERN_DEBUG
"%s: CCMP decrypt failed "
586 "for RX frame from %s\n", rx
->dev
->name
,
587 print_mac(mac
, rx
->sta
->addr
));
588 #endif /* CONFIG_MAC80211_DEBUG */
589 return RX_DROP_UNUSABLE
;
593 memcpy(key
->u
.ccmp
.rx_pn
[rx
->queue
], pn
, CCMP_PN_LEN
);
595 /* Remove CCMP header and MIC */
596 skb_trim(skb
, skb
->len
- CCMP_MIC_LEN
);
597 memmove(skb
->data
+ CCMP_HDR_LEN
, skb
->data
, hdrlen
);
598 skb_pull(skb
, CCMP_HDR_LEN
);