blob: 45709ada8fee2c2ba222d7e8fb5743e62b2f6d27 [file] [log] [blame]
Jiri Bencf0706e82007-05-05 11:45:53 -07001/*
2 * Copyright 2002-2004, Instant802 Networks, Inc.
3 *
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.
7 */
8
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>
Jiri Bencf0706e82007-05-05 11:45:53 -070014#include <net/mac80211.h>
Johannes Bergeb063c12007-08-28 17:01:53 -040015
Jiri Bencf0706e82007-05-05 11:45:53 -070016#include "ieee80211_i.h"
17#include "michael.h"
18#include "tkip.h"
19#include "aes_ccm.h"
20#include "wpa.h"
21
22static int ieee80211_get_hdr_info(const struct sk_buff *skb, u8 **sa, u8 **da,
23 u8 *qos_tid, u8 **data, size_t *data_len)
24{
25 struct ieee80211_hdr *hdr;
26 size_t hdrlen;
27 u16 fc;
28 int a4_included;
29 u8 *pos;
30
31 hdr = (struct ieee80211_hdr *) skb->data;
32 fc = le16_to_cpu(hdr->frame_control);
33
34 hdrlen = 24;
35 if ((fc & (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) ==
36 (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) {
37 hdrlen += ETH_ALEN;
38 *sa = hdr->addr4;
39 *da = hdr->addr3;
40 } else if (fc & IEEE80211_FCTL_FROMDS) {
41 *sa = hdr->addr3;
42 *da = hdr->addr1;
43 } else if (fc & IEEE80211_FCTL_TODS) {
44 *sa = hdr->addr2;
45 *da = hdr->addr3;
46 } else {
47 *sa = hdr->addr2;
48 *da = hdr->addr1;
49 }
50
51 if (fc & 0x80)
52 hdrlen += 2;
53
54 *data = skb->data + hdrlen;
55 *data_len = skb->len - hdrlen;
56
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;
62 if (a4_included)
63 pos += 6;
64 *qos_tid = pos[0] & 0x0f;
65 *qos_tid |= 0x80; /* qos_included flag */
66 } else
67 *qos_tid = 0;
68
69 return skb->len < hdrlen ? -1 : 0;
70}
71
72
Johannes Berg9ae54c82008-01-31 19:48:20 +010073ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +010074ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
Jiri Bencf0706e82007-05-05 11:45:53 -070075{
76 u8 *data, *sa, *da, *key, *mic, qos_tid;
77 size_t data_len;
78 u16 fc;
79 struct sk_buff *skb = tx->skb;
80 int authenticator;
81 int wpa_test = 0;
82
83 fc = tx->fc;
84
Johannes Berg8f20fc22007-08-28 17:01:54 -040085 if (!tx->key || tx->key->conf.alg != ALG_TKIP || skb->len < 24 ||
Jiri Bencf0706e82007-05-05 11:45:53 -070086 !WLAN_FC_DATA_PRESENT(fc))
Johannes Berg9ae54c82008-01-31 19:48:20 +010087 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -070088
89 if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len))
Johannes Berg9ae54c82008-01-31 19:48:20 +010090 return TX_DROP;
Jiri Bencf0706e82007-05-05 11:45:53 -070091
Johannes Berg11a843b2007-08-28 17:01:55 -040092 if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
Johannes Berg5cf121c2008-02-25 16:27:43 +010093 !(tx->flags & IEEE80211_TX_FRAGMENTED) &&
Johannes Berg7848ba72007-09-14 11:10:25 -040094 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) &&
Jiri Bencf0706e82007-05-05 11:45:53 -070095 !wpa_test) {
96 /* hwaccel - with no need for preallocated room for Michael MIC
97 */
Johannes Berg9ae54c82008-01-31 19:48:20 +010098 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -070099 }
100
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,
105 GFP_ATOMIC))) {
106 printk(KERN_DEBUG "%s: failed to allocate more memory "
107 "for Michael MIC\n", tx->dev->name);
Johannes Berg9ae54c82008-01-31 19:48:20 +0100108 return TX_DROP;
Jiri Bencf0706e82007-05-05 11:45:53 -0700109 }
110 }
111
112#if 0
113 authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */
114#else
115 authenticator = 1;
116#endif
Johannes Berg8f20fc22007-08-28 17:01:54 -0400117 key = &tx->key->conf.key[authenticator ? ALG_TKIP_TEMP_AUTH_TX_MIC_KEY :
118 ALG_TKIP_TEMP_AUTH_RX_MIC_KEY];
Jiri Bencf0706e82007-05-05 11:45:53 -0700119 mic = skb_put(skb, MICHAEL_MIC_LEN);
120 michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);
121
Johannes Berg9ae54c82008-01-31 19:48:20 +0100122 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700123}
124
125
Johannes Berg9ae54c82008-01-31 19:48:20 +0100126ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100127ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700128{
129 u8 *data, *sa, *da, *key = NULL, qos_tid;
130 size_t data_len;
131 u16 fc;
132 u8 mic[MICHAEL_MIC_LEN];
133 struct sk_buff *skb = rx->skb;
134 int authenticator = 1, wpa_test = 0;
Joe Perches0795af52007-10-03 17:59:30 -0700135 DECLARE_MAC_BUF(mac);
Jiri Bencf0706e82007-05-05 11:45:53 -0700136
137 fc = rx->fc;
138
Johannes Berg3017b802007-08-28 17:01:53 -0400139 /*
140 * No way to verify the MIC if the hardware stripped it
141 */
Johannes Berg5cf121c2008-02-25 16:27:43 +0100142 if (rx->status->flag & RX_FLAG_MMIC_STRIPPED)
Johannes Berg9ae54c82008-01-31 19:48:20 +0100143 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700144
Johannes Berg8f20fc22007-08-28 17:01:54 -0400145 if (!rx->key || rx->key->conf.alg != ALG_TKIP ||
Jiri Bencf0706e82007-05-05 11:45:53 -0700146 !(rx->fc & IEEE80211_FCTL_PROTECTED) || !WLAN_FC_DATA_PRESENT(fc))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100147 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700148
Jiri Bencf0706e82007-05-05 11:45:53 -0700149 if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len)
150 || data_len < MICHAEL_MIC_LEN)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100151 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700152
153 data_len -= MICHAEL_MIC_LEN;
154
155#if 0
156 authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */
157#else
158 authenticator = 1;
159#endif
Johannes Berg8f20fc22007-08-28 17:01:54 -0400160 key = &rx->key->conf.key[authenticator ? ALG_TKIP_TEMP_AUTH_RX_MIC_KEY :
161 ALG_TKIP_TEMP_AUTH_TX_MIC_KEY];
Jiri Bencf0706e82007-05-05 11:45:53 -0700162 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) {
Johannes Berg5cf121c2008-02-25 16:27:43 +0100164 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
Johannes Berge4c26ad2008-01-31 19:48:21 +0100165 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700166
167 printk(KERN_DEBUG "%s: invalid Michael MIC in data frame from "
Joe Perches0795af52007-10-03 17:59:30 -0700168 "%s\n", rx->dev->name, print_mac(mac, sa));
Jiri Bencf0706e82007-05-05 11:45:53 -0700169
Johannes Berg8f20fc22007-08-28 17:01:54 -0400170 mac80211_ev_michael_mic_failure(rx->dev, rx->key->conf.keyidx,
Johannes Bergeb063c12007-08-28 17:01:53 -0400171 (void *) skb->data);
Johannes Berge4c26ad2008-01-31 19:48:21 +0100172 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700173 }
174
Jiri Bencf0706e82007-05-05 11:45:53 -0700175 /* remove Michael MIC from payload */
176 skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
177
Johannes Berg50741ae2007-09-26 15:19:45 +0200178 /* update IV in key information to be able to detect replays */
Johannes Berg5cf121c2008-02-25 16:27:43 +0100179 rx->key->u.tkip.iv32_rx[rx->queue] = rx->tkip_iv32;
180 rx->key->u.tkip.iv16_rx[rx->queue] = rx->tkip_iv16;
Johannes Berg50741ae2007-09-26 15:19:45 +0200181
Johannes Berg9ae54c82008-01-31 19:48:20 +0100182 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700183}
184
185
Johannes Berg5cf121c2008-02-25 16:27:43 +0100186static int tkip_encrypt_skb(struct ieee80211_tx_data *tx,
Jiri Bencf0706e82007-05-05 11:45:53 -0700187 struct sk_buff *skb, int test)
188{
189 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
190 struct ieee80211_key *key = tx->key;
191 int hdrlen, len, tailneed;
192 u16 fc;
193 u8 *pos;
194
195 fc = le16_to_cpu(hdr->frame_control);
196 hdrlen = ieee80211_get_hdrlen(fc);
197 len = skb->len - hdrlen;
198
Johannes Berg11a843b2007-08-28 17:01:55 -0400199 if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
Johannes Berg8f20fc22007-08-28 17:01:54 -0400200 tailneed = 0;
Johannes Berg11a843b2007-08-28 17:01:55 -0400201 else
202 tailneed = TKIP_ICV_LEN;
Johannes Berg8f20fc22007-08-28 17:01:54 -0400203
Jiri Bencf0706e82007-05-05 11:45:53 -0700204 if ((skb_headroom(skb) < TKIP_IV_LEN ||
205 skb_tailroom(skb) < tailneed)) {
206 I802_DEBUG_INC(tx->local->tx_expand_skb_head);
207 if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN, tailneed,
208 GFP_ATOMIC)))
209 return -1;
210 }
211
212 pos = skb_push(skb, TKIP_IV_LEN);
213 memmove(pos, pos + TKIP_IV_LEN, hdrlen);
214 pos += hdrlen;
215
216 /* Increase IV for the frame */
217 key->u.tkip.iv16++;
218 if (key->u.tkip.iv16 == 0)
219 key->u.tkip.iv32++;
220
Johannes Berg11a843b2007-08-28 17:01:55 -0400221 if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
Jiri Bencf0706e82007-05-05 11:45:53 -0700222 hdr = (struct ieee80211_hdr *)skb->data;
223
224 /* hwaccel - with preallocated room for IV */
225 ieee80211_tkip_add_iv(pos, key,
226 (u8) (key->u.tkip.iv16 >> 8),
227 (u8) (((key->u.tkip.iv16 >> 8) | 0x20) &
228 0x7f),
229 (u8) key->u.tkip.iv16);
230
Johannes Berg5cf121c2008-02-25 16:27:43 +0100231 tx->control->key_idx = tx->key->conf.hw_key_idx;
Jiri Bencf0706e82007-05-05 11:45:53 -0700232 return 0;
233 }
234
235 /* Add room for ICV */
236 skb_put(skb, TKIP_ICV_LEN);
237
238 hdr = (struct ieee80211_hdr *) skb->data;
239 ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
240 key, pos, len, hdr->addr2);
241 return 0;
242}
243
244
Johannes Berg9ae54c82008-01-31 19:48:20 +0100245ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100246ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700247{
Jiri Bencf0706e82007-05-05 11:45:53 -0700248 struct sk_buff *skb = tx->skb;
249 int wpa_test = 0, test = 0;
250
Johannes Berg5cf121c2008-02-25 16:27:43 +0100251 tx->control->icv_len = TKIP_ICV_LEN;
252 tx->control->iv_len = TKIP_IV_LEN;
253 ieee80211_tx_set_protected(tx);
Jiri Bencf0706e82007-05-05 11:45:53 -0700254
Johannes Berg11a843b2007-08-28 17:01:55 -0400255 if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
Johannes Berg7848ba72007-09-14 11:10:25 -0400256 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
Jiri Bencf0706e82007-05-05 11:45:53 -0700257 !wpa_test) {
258 /* hwaccel - with no need for preallocated room for IV/ICV */
Johannes Berg5cf121c2008-02-25 16:27:43 +0100259 tx->control->key_idx = tx->key->conf.hw_key_idx;
Johannes Berg9ae54c82008-01-31 19:48:20 +0100260 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700261 }
262
263 if (tkip_encrypt_skb(tx, skb, test) < 0)
Johannes Berg9ae54c82008-01-31 19:48:20 +0100264 return TX_DROP;
Jiri Bencf0706e82007-05-05 11:45:53 -0700265
Johannes Berg5cf121c2008-02-25 16:27:43 +0100266 if (tx->extra_frag) {
Jiri Bencf0706e82007-05-05 11:45:53 -0700267 int i;
Johannes Berg5cf121c2008-02-25 16:27:43 +0100268 for (i = 0; i < tx->num_extra_frag; i++) {
269 if (tkip_encrypt_skb(tx, tx->extra_frag[i], test)
Jiri Bencf0706e82007-05-05 11:45:53 -0700270 < 0)
Johannes Berg9ae54c82008-01-31 19:48:20 +0100271 return TX_DROP;
Jiri Bencf0706e82007-05-05 11:45:53 -0700272 }
273 }
274
Johannes Berg9ae54c82008-01-31 19:48:20 +0100275 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700276}
277
278
Johannes Berg9ae54c82008-01-31 19:48:20 +0100279ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100280ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700281{
282 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
283 u16 fc;
284 int hdrlen, res, hwaccel = 0, wpa_test = 0;
285 struct ieee80211_key *key = rx->key;
286 struct sk_buff *skb = rx->skb;
Joe Perches0795af52007-10-03 17:59:30 -0700287 DECLARE_MAC_BUF(mac);
Jiri Bencf0706e82007-05-05 11:45:53 -0700288
289 fc = le16_to_cpu(hdr->frame_control);
290 hdrlen = ieee80211_get_hdrlen(fc);
291
Johannes Berg4f0d18e2007-09-26 15:19:40 +0200292 if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
Johannes Berg9ae54c82008-01-31 19:48:20 +0100293 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700294
295 if (!rx->sta || skb->len - hdrlen < 12)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100296 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700297
Johannes Berg5cf121c2008-02-25 16:27:43 +0100298 if (rx->status->flag & RX_FLAG_DECRYPTED) {
299 if (rx->status->flag & RX_FLAG_IV_STRIPPED) {
Johannes Berg7848ba72007-09-14 11:10:25 -0400300 /*
301 * Hardware took care of all processing, including
302 * replay protection, and stripped the ICV/IV so
303 * we cannot do any checks here.
304 */
Johannes Berg9ae54c82008-01-31 19:48:20 +0100305 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700306 }
307
308 /* let TKIP code verify IV, but skip decryption */
309 hwaccel = 1;
310 }
311
312 res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
313 key, skb->data + hdrlen,
314 skb->len - hdrlen, rx->sta->addr,
Emmanuel Grumbach9ae4fda2008-03-20 15:06:42 +0200315 hdr->addr1, hwaccel, rx->queue,
Johannes Berg5cf121c2008-02-25 16:27:43 +0100316 &rx->tkip_iv32,
317 &rx->tkip_iv16);
Jiri Bencf0706e82007-05-05 11:45:53 -0700318 if (res != TKIP_DECRYPT_OK || wpa_test) {
John W. Linville7f3ad892007-11-06 17:12:31 -0500319#ifdef CONFIG_MAC80211_DEBUG
320 if (net_ratelimit())
321 printk(KERN_DEBUG "%s: TKIP decrypt failed for RX "
322 "frame from %s (res=%d)\n", rx->dev->name,
323 print_mac(mac, rx->sta->addr), res);
324#endif /* CONFIG_MAC80211_DEBUG */
Johannes Berge4c26ad2008-01-31 19:48:21 +0100325 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700326 }
327
328 /* Trim ICV */
329 skb_trim(skb, skb->len - TKIP_ICV_LEN);
330
331 /* Remove IV */
332 memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen);
333 skb_pull(skb, TKIP_IV_LEN);
334
Johannes Berg9ae54c82008-01-31 19:48:20 +0100335 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700336}
337
338
339static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad,
340 int encrypted)
341{
342 u16 fc;
343 int a4_included, qos_included;
344 u8 qos_tid, *fc_pos, *data, *sa, *da;
345 int len_a;
346 size_t data_len;
347 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
348
349 fc_pos = (u8 *) &hdr->frame_control;
350 fc = fc_pos[0] ^ (fc_pos[1] << 8);
351 a4_included = (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
352 (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS);
353
354 ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len);
355 data_len -= CCMP_HDR_LEN + (encrypted ? CCMP_MIC_LEN : 0);
356 if (qos_tid & 0x80) {
357 qos_included = 1;
358 qos_tid &= 0x0f;
359 } else
360 qos_included = 0;
361 /* First block, b_0 */
362
363 b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
364 /* Nonce: QoS Priority | A2 | PN */
365 b_0[1] = qos_tid;
366 memcpy(&b_0[2], hdr->addr2, 6);
367 memcpy(&b_0[8], pn, CCMP_PN_LEN);
368 /* l(m) */
369 b_0[14] = (data_len >> 8) & 0xff;
370 b_0[15] = data_len & 0xff;
371
372
373 /* AAD (extra authenticate-only data) / masked 802.11 header
374 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
375
376 len_a = a4_included ? 28 : 22;
377 if (qos_included)
378 len_a += 2;
379
380 aad[0] = 0; /* (len_a >> 8) & 0xff; */
381 aad[1] = len_a & 0xff;
382 /* Mask FC: zero subtype b4 b5 b6 */
383 aad[2] = fc_pos[0] & ~(BIT(4) | BIT(5) | BIT(6));
384 /* Retry, PwrMgt, MoreData; set Protected */
385 aad[3] = (fc_pos[1] & ~(BIT(3) | BIT(4) | BIT(5))) | BIT(6);
386 memcpy(&aad[4], &hdr->addr1, 18);
387
388 /* Mask Seq#, leave Frag# */
389 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
390 aad[23] = 0;
391 if (a4_included) {
392 memcpy(&aad[24], hdr->addr4, 6);
393 aad[30] = 0;
394 aad[31] = 0;
395 } else
396 memset(&aad[24], 0, 8);
397 if (qos_included) {
398 u8 *dpos = &aad[a4_included ? 30 : 24];
399
400 /* Mask QoS Control field */
401 dpos[0] = qos_tid;
402 dpos[1] = 0;
403 }
404}
405
406
407static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
408{
409 hdr[0] = pn[5];
410 hdr[1] = pn[4];
411 hdr[2] = 0;
412 hdr[3] = 0x20 | (key_id << 6);
413 hdr[4] = pn[3];
414 hdr[5] = pn[2];
415 hdr[6] = pn[1];
416 hdr[7] = pn[0];
417}
418
419
420static inline int ccmp_hdr2pn(u8 *pn, u8 *hdr)
421{
422 pn[0] = hdr[7];
423 pn[1] = hdr[6];
424 pn[2] = hdr[5];
425 pn[3] = hdr[4];
426 pn[4] = hdr[1];
427 pn[5] = hdr[0];
428 return (hdr[3] >> 6) & 0x03;
429}
430
431
Johannes Berg5cf121c2008-02-25 16:27:43 +0100432static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx,
Jiri Bencf0706e82007-05-05 11:45:53 -0700433 struct sk_buff *skb, int test)
434{
435 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
436 struct ieee80211_key *key = tx->key;
437 int hdrlen, len, tailneed;
438 u16 fc;
439 u8 *pos, *pn, *b_0, *aad, *scratch;
440 int i;
441
442 scratch = key->u.ccmp.tx_crypto_buf;
443 b_0 = scratch + 3 * AES_BLOCK_LEN;
444 aad = scratch + 4 * AES_BLOCK_LEN;
445
446 fc = le16_to_cpu(hdr->frame_control);
447 hdrlen = ieee80211_get_hdrlen(fc);
448 len = skb->len - hdrlen;
449
Johannes Berg11a843b2007-08-28 17:01:55 -0400450 if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
Johannes Berg8f20fc22007-08-28 17:01:54 -0400451 tailneed = 0;
Johannes Berg11a843b2007-08-28 17:01:55 -0400452 else
453 tailneed = CCMP_MIC_LEN;
Jiri Bencf0706e82007-05-05 11:45:53 -0700454
455 if ((skb_headroom(skb) < CCMP_HDR_LEN ||
456 skb_tailroom(skb) < tailneed)) {
457 I802_DEBUG_INC(tx->local->tx_expand_skb_head);
458 if (unlikely(pskb_expand_head(skb, CCMP_HDR_LEN, tailneed,
459 GFP_ATOMIC)))
460 return -1;
461 }
462
463 pos = skb_push(skb, CCMP_HDR_LEN);
464 memmove(pos, pos + CCMP_HDR_LEN, hdrlen);
465 hdr = (struct ieee80211_hdr *) pos;
466 pos += hdrlen;
467
468 /* PN = PN + 1 */
469 pn = key->u.ccmp.tx_pn;
470
471 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
472 pn[i]++;
473 if (pn[i])
474 break;
475 }
476
Johannes Berg8f20fc22007-08-28 17:01:54 -0400477 ccmp_pn2hdr(pos, pn, key->conf.keyidx);
Jiri Bencf0706e82007-05-05 11:45:53 -0700478
Johannes Berg11a843b2007-08-28 17:01:55 -0400479 if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
Jiri Bencf0706e82007-05-05 11:45:53 -0700480 /* hwaccel - with preallocated room for CCMP header */
Johannes Berg5cf121c2008-02-25 16:27:43 +0100481 tx->control->key_idx = key->conf.hw_key_idx;
Jiri Bencf0706e82007-05-05 11:45:53 -0700482 return 0;
483 }
484
485 pos += CCMP_HDR_LEN;
486 ccmp_special_blocks(skb, pn, b_0, aad, 0);
487 ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, b_0, aad, pos, len,
488 pos, skb_put(skb, CCMP_MIC_LEN));
489
490 return 0;
491}
492
493
Johannes Berg9ae54c82008-01-31 19:48:20 +0100494ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100495ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700496{
Jiri Bencf0706e82007-05-05 11:45:53 -0700497 struct sk_buff *skb = tx->skb;
498 int test = 0;
499
Johannes Berg5cf121c2008-02-25 16:27:43 +0100500 tx->control->icv_len = CCMP_MIC_LEN;
501 tx->control->iv_len = CCMP_HDR_LEN;
502 ieee80211_tx_set_protected(tx);
Jiri Bencf0706e82007-05-05 11:45:53 -0700503
Johannes Berg11a843b2007-08-28 17:01:55 -0400504 if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
Johannes Berg7848ba72007-09-14 11:10:25 -0400505 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
Jiri Bencf0706e82007-05-05 11:45:53 -0700506 /* hwaccel - with no need for preallocated room for CCMP "
507 * header or MIC fields */
Johannes Berg5cf121c2008-02-25 16:27:43 +0100508 tx->control->key_idx = tx->key->conf.hw_key_idx;
Johannes Berg9ae54c82008-01-31 19:48:20 +0100509 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700510 }
511
512 if (ccmp_encrypt_skb(tx, skb, test) < 0)
Johannes Berg9ae54c82008-01-31 19:48:20 +0100513 return TX_DROP;
Jiri Bencf0706e82007-05-05 11:45:53 -0700514
Johannes Berg5cf121c2008-02-25 16:27:43 +0100515 if (tx->extra_frag) {
Jiri Bencf0706e82007-05-05 11:45:53 -0700516 int i;
Johannes Berg5cf121c2008-02-25 16:27:43 +0100517 for (i = 0; i < tx->num_extra_frag; i++) {
518 if (ccmp_encrypt_skb(tx, tx->extra_frag[i], test)
Jiri Bencf0706e82007-05-05 11:45:53 -0700519 < 0)
Johannes Berg9ae54c82008-01-31 19:48:20 +0100520 return TX_DROP;
Jiri Bencf0706e82007-05-05 11:45:53 -0700521 }
522 }
523
Johannes Berg9ae54c82008-01-31 19:48:20 +0100524 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700525}
526
527
Johannes Berg9ae54c82008-01-31 19:48:20 +0100528ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100529ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700530{
531 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
532 u16 fc;
533 int hdrlen;
534 struct ieee80211_key *key = rx->key;
535 struct sk_buff *skb = rx->skb;
536 u8 pn[CCMP_PN_LEN];
537 int data_len;
Joe Perches0795af52007-10-03 17:59:30 -0700538 DECLARE_MAC_BUF(mac);
Jiri Bencf0706e82007-05-05 11:45:53 -0700539
540 fc = le16_to_cpu(hdr->frame_control);
541 hdrlen = ieee80211_get_hdrlen(fc);
542
Johannes Berg4f0d18e2007-09-26 15:19:40 +0200543 if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
Johannes Berg9ae54c82008-01-31 19:48:20 +0100544 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700545
546 data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
547 if (!rx->sta || data_len < 0)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100548 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700549
Johannes Berg5cf121c2008-02-25 16:27:43 +0100550 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
551 (rx->status->flag & RX_FLAG_IV_STRIPPED))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100552 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700553
554 (void) ccmp_hdr2pn(pn, skb->data + hdrlen);
555
Johannes Berg5cf121c2008-02-25 16:27:43 +0100556 if (memcmp(pn, key->u.ccmp.rx_pn[rx->queue], CCMP_PN_LEN) <= 0) {
Jiri Bencf0706e82007-05-05 11:45:53 -0700557#ifdef CONFIG_MAC80211_DEBUG
Johannes Berg5cf121c2008-02-25 16:27:43 +0100558 u8 *ppn = key->u.ccmp.rx_pn[rx->queue];
Joe Perches0795af52007-10-03 17:59:30 -0700559
Jiri Bencf0706e82007-05-05 11:45:53 -0700560 printk(KERN_DEBUG "%s: CCMP replay detected for RX frame from "
Joe Perches0795af52007-10-03 17:59:30 -0700561 "%s (RX PN %02x%02x%02x%02x%02x%02x <= prev. PN "
Jiri Bencf0706e82007-05-05 11:45:53 -0700562 "%02x%02x%02x%02x%02x%02x)\n", rx->dev->name,
Joe Perches0795af52007-10-03 17:59:30 -0700563 print_mac(mac, rx->sta->addr),
Jiri Bencf0706e82007-05-05 11:45:53 -0700564 pn[0], pn[1], pn[2], pn[3], pn[4], pn[5],
565 ppn[0], ppn[1], ppn[2], ppn[3], ppn[4], ppn[5]);
566#endif /* CONFIG_MAC80211_DEBUG */
567 key->u.ccmp.replays++;
Johannes Berge4c26ad2008-01-31 19:48:21 +0100568 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700569 }
570
Johannes Berg5cf121c2008-02-25 16:27:43 +0100571 if (!(rx->status->flag & RX_FLAG_DECRYPTED)) {
Johannes Berg7848ba72007-09-14 11:10:25 -0400572 /* hardware didn't decrypt/verify MIC */
Jiri Bencf0706e82007-05-05 11:45:53 -0700573 u8 *scratch, *b_0, *aad;
574
575 scratch = key->u.ccmp.rx_crypto_buf;
576 b_0 = scratch + 3 * AES_BLOCK_LEN;
577 aad = scratch + 4 * AES_BLOCK_LEN;
578
579 ccmp_special_blocks(skb, pn, b_0, aad, 1);
580
581 if (ieee80211_aes_ccm_decrypt(
582 key->u.ccmp.tfm, scratch, b_0, aad,
583 skb->data + hdrlen + CCMP_HDR_LEN, data_len,
584 skb->data + skb->len - CCMP_MIC_LEN,
585 skb->data + hdrlen + CCMP_HDR_LEN)) {
John W. Linville7f3ad892007-11-06 17:12:31 -0500586#ifdef CONFIG_MAC80211_DEBUG
587 if (net_ratelimit())
588 printk(KERN_DEBUG "%s: CCMP decrypt failed "
589 "for RX frame from %s\n", rx->dev->name,
590 print_mac(mac, rx->sta->addr));
591#endif /* CONFIG_MAC80211_DEBUG */
Johannes Berge4c26ad2008-01-31 19:48:21 +0100592 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700593 }
594 }
595
Johannes Berg5cf121c2008-02-25 16:27:43 +0100596 memcpy(key->u.ccmp.rx_pn[rx->queue], pn, CCMP_PN_LEN);
Jiri Bencf0706e82007-05-05 11:45:53 -0700597
598 /* Remove CCMP header and MIC */
599 skb_trim(skb, skb->len - CCMP_MIC_LEN);
600 memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen);
601 skb_pull(skb, CCMP_HDR_LEN);
602
Johannes Berg9ae54c82008-01-31 19:48:20 +0100603 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700604}