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-rw-r--r--net/mac80211/wpa.c152
1 files changed, 144 insertions, 8 deletions
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 7aa63caf8d50..9101b48ec2ae 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -1,5 +1,6 @@
1/* 1/*
2 * Copyright 2002-2004, Instant802 Networks, Inc. 2 * Copyright 2002-2004, Instant802 Networks, Inc.
3 * Copyright 2008, Jouni Malinen <j@w1.fi>
3 * 4 *
4 * This program is free software; you can redistribute it and/or modify 5 * 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 * it under the terms of the GNU General Public License version 2 as
@@ -19,6 +20,7 @@
19#include "michael.h" 20#include "michael.h"
20#include "tkip.h" 21#include "tkip.h"
21#include "aes_ccm.h" 22#include "aes_ccm.h"
23#include "aes_cmac.h"
22#include "wpa.h" 24#include "wpa.h"
23 25
24ieee80211_tx_result 26ieee80211_tx_result
@@ -266,7 +268,7 @@ static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch,
266 int encrypted) 268 int encrypted)
267{ 269{
268 __le16 mask_fc; 270 __le16 mask_fc;
269 int a4_included; 271 int a4_included, mgmt;
270 u8 qos_tid; 272 u8 qos_tid;
271 u8 *b_0, *aad; 273 u8 *b_0, *aad;
272 u16 data_len, len_a; 274 u16 data_len, len_a;
@@ -277,12 +279,15 @@ static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch,
277 aad = scratch + 4 * AES_BLOCK_LEN; 279 aad = scratch + 4 * AES_BLOCK_LEN;
278 280
279 /* 281 /*
280 * Mask FC: zero subtype b4 b5 b6 282 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
281 * Retry, PwrMgt, MoreData; set Protected 283 * Retry, PwrMgt, MoreData; set Protected
282 */ 284 */
285 mgmt = ieee80211_is_mgmt(hdr->frame_control);
283 mask_fc = hdr->frame_control; 286 mask_fc = hdr->frame_control;
284 mask_fc &= ~cpu_to_le16(0x0070 | IEEE80211_FCTL_RETRY | 287 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
285 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); 288 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
289 if (!mgmt)
290 mask_fc &= ~cpu_to_le16(0x0070);
286 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); 291 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
287 292
288 hdrlen = ieee80211_hdrlen(hdr->frame_control); 293 hdrlen = ieee80211_hdrlen(hdr->frame_control);
@@ -300,8 +305,10 @@ static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch,
300 305
301 /* First block, b_0 */ 306 /* First block, b_0 */
302 b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */ 307 b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
303 /* Nonce: QoS Priority | A2 | PN */ 308 /* Nonce: Nonce Flags | A2 | PN
304 b_0[1] = qos_tid; 309 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
310 */
311 b_0[1] = qos_tid | (mgmt << 4);
305 memcpy(&b_0[2], hdr->addr2, ETH_ALEN); 312 memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
306 memcpy(&b_0[8], pn, CCMP_PN_LEN); 313 memcpy(&b_0[8], pn, CCMP_PN_LEN);
307 /* l(m) */ 314 /* l(m) */
@@ -360,9 +367,14 @@ static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
360 int hdrlen, len, tail; 367 int hdrlen, len, tail;
361 u8 *pos, *pn; 368 u8 *pos, *pn;
362 int i; 369 int i;
370 bool skip_hw;
371
372 skip_hw = (tx->key->conf.flags & IEEE80211_KEY_FLAG_SW_MGMT) &&
373 ieee80211_is_mgmt(hdr->frame_control);
363 374
364 if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && 375 if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
365 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) { 376 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
377 !skip_hw) {
366 /* hwaccel - with no need for preallocated room for CCMP 378 /* hwaccel - with no need for preallocated room for CCMP
367 * header or MIC fields */ 379 * header or MIC fields */
368 info->control.hw_key = &tx->key->conf; 380 info->control.hw_key = &tx->key->conf;
@@ -397,7 +409,7 @@ static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
397 409
398 ccmp_pn2hdr(pos, pn, key->conf.keyidx); 410 ccmp_pn2hdr(pos, pn, key->conf.keyidx);
399 411
400 if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) { 412 if ((key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && !skip_hw) {
401 /* hwaccel - with preallocated room for CCMP header */ 413 /* hwaccel - with preallocated room for CCMP header */
402 info->control.hw_key = &tx->key->conf; 414 info->control.hw_key = &tx->key->conf;
403 return 0; 415 return 0;
@@ -446,7 +458,8 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
446 458
447 hdrlen = ieee80211_hdrlen(hdr->frame_control); 459 hdrlen = ieee80211_hdrlen(hdr->frame_control);
448 460
449 if (!ieee80211_is_data(hdr->frame_control)) 461 if (!ieee80211_is_data(hdr->frame_control) &&
462 !ieee80211_is_robust_mgmt_frame(hdr))
450 return RX_CONTINUE; 463 return RX_CONTINUE;
451 464
452 data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN; 465 data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
@@ -485,3 +498,126 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
485 498
486 return RX_CONTINUE; 499 return RX_CONTINUE;
487} 500}
501
502
503static void bip_aad(struct sk_buff *skb, u8 *aad)
504{
505 /* BIP AAD: FC(masked) || A1 || A2 || A3 */
506
507 /* FC type/subtype */
508 aad[0] = skb->data[0];
509 /* Mask FC Retry, PwrMgt, MoreData flags to zero */
510 aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6));
511 /* A1 || A2 || A3 */
512 memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN);
513}
514
515
516static inline void bip_ipn_swap(u8 *d, const u8 *s)
517{
518 *d++ = s[5];
519 *d++ = s[4];
520 *d++ = s[3];
521 *d++ = s[2];
522 *d++ = s[1];
523 *d = s[0];
524}
525
526
527ieee80211_tx_result
528ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
529{
530 struct sk_buff *skb = tx->skb;
531 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
532 struct ieee80211_key *key = tx->key;
533 struct ieee80211_mmie *mmie;
534 u8 *pn, aad[20];
535 int i;
536
537 if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
538 /* hwaccel */
539 info->control.hw_key = &tx->key->conf;
540 return 0;
541 }
542
543 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
544 return TX_DROP;
545
546 mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
547 mmie->element_id = WLAN_EID_MMIE;
548 mmie->length = sizeof(*mmie) - 2;
549 mmie->key_id = cpu_to_le16(key->conf.keyidx);
550
551 /* PN = PN + 1 */
552 pn = key->u.aes_cmac.tx_pn;
553
554 for (i = sizeof(key->u.aes_cmac.tx_pn) - 1; i >= 0; i--) {
555 pn[i]++;
556 if (pn[i])
557 break;
558 }
559 bip_ipn_swap(mmie->sequence_number, pn);
560
561 bip_aad(skb, aad);
562
563 /*
564 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
565 */
566 ieee80211_aes_cmac(key->u.aes_cmac.tfm, key->u.aes_cmac.tx_crypto_buf,
567 aad, skb->data + 24, skb->len - 24, mmie->mic);
568
569 return TX_CONTINUE;
570}
571
572
573ieee80211_rx_result
574ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
575{
576 struct sk_buff *skb = rx->skb;
577 struct ieee80211_key *key = rx->key;
578 struct ieee80211_mmie *mmie;
579 u8 aad[20], mic[8], ipn[6];
580 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
581
582 if (!ieee80211_is_mgmt(hdr->frame_control))
583 return RX_CONTINUE;
584
585 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
586 (rx->status->flag & RX_FLAG_IV_STRIPPED))
587 return RX_CONTINUE;
588
589 if (skb->len < 24 + sizeof(*mmie))
590 return RX_DROP_UNUSABLE;
591
592 mmie = (struct ieee80211_mmie *)
593 (skb->data + skb->len - sizeof(*mmie));
594 if (mmie->element_id != WLAN_EID_MMIE ||
595 mmie->length != sizeof(*mmie) - 2)
596 return RX_DROP_UNUSABLE; /* Invalid MMIE */
597
598 bip_ipn_swap(ipn, mmie->sequence_number);
599
600 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
601 key->u.aes_cmac.replays++;
602 return RX_DROP_UNUSABLE;
603 }
604
605 if (!(rx->status->flag & RX_FLAG_DECRYPTED)) {
606 /* hardware didn't decrypt/verify MIC */
607 bip_aad(skb, aad);
608 ieee80211_aes_cmac(key->u.aes_cmac.tfm,
609 key->u.aes_cmac.rx_crypto_buf, aad,
610 skb->data + 24, skb->len - 24, mic);
611 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
612 key->u.aes_cmac.icverrors++;
613 return RX_DROP_UNUSABLE;
614 }
615 }
616
617 memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
618
619 /* Remove MMIE */
620 skb_trim(skb, skb->len - sizeof(*mmie));
621
622 return RX_CONTINUE;
623}