Commit | Line | Data |
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f0706e82 JB |
1 | /* |
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> | |
14 | #include <net/iw_handler.h> | |
15 | ||
16 | #include <net/mac80211.h> | |
17 | #include "ieee80211_common.h" | |
18 | #include "ieee80211_i.h" | |
19 | #include "michael.h" | |
20 | #include "tkip.h" | |
21 | #include "aes_ccm.h" | |
22 | #include "wpa.h" | |
23 | ||
24 | static int ieee80211_get_hdr_info(const struct sk_buff *skb, u8 **sa, u8 **da, | |
25 | u8 *qos_tid, u8 **data, size_t *data_len) | |
26 | { | |
27 | struct ieee80211_hdr *hdr; | |
28 | size_t hdrlen; | |
29 | u16 fc; | |
30 | int a4_included; | |
31 | u8 *pos; | |
32 | ||
33 | hdr = (struct ieee80211_hdr *) skb->data; | |
34 | fc = le16_to_cpu(hdr->frame_control); | |
35 | ||
36 | hdrlen = 24; | |
37 | if ((fc & (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) == | |
38 | (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) { | |
39 | hdrlen += ETH_ALEN; | |
40 | *sa = hdr->addr4; | |
41 | *da = hdr->addr3; | |
42 | } else if (fc & IEEE80211_FCTL_FROMDS) { | |
43 | *sa = hdr->addr3; | |
44 | *da = hdr->addr1; | |
45 | } else if (fc & IEEE80211_FCTL_TODS) { | |
46 | *sa = hdr->addr2; | |
47 | *da = hdr->addr3; | |
48 | } else { | |
49 | *sa = hdr->addr2; | |
50 | *da = hdr->addr1; | |
51 | } | |
52 | ||
53 | if (fc & 0x80) | |
54 | hdrlen += 2; | |
55 | ||
56 | *data = skb->data + hdrlen; | |
57 | *data_len = skb->len - hdrlen; | |
58 | ||
59 | a4_included = (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) == | |
60 | (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS); | |
61 | if ((fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA && | |
62 | fc & IEEE80211_STYPE_QOS_DATA) { | |
63 | pos = (u8 *) &hdr->addr4; | |
64 | if (a4_included) | |
65 | pos += 6; | |
66 | *qos_tid = pos[0] & 0x0f; | |
67 | *qos_tid |= 0x80; /* qos_included flag */ | |
68 | } else | |
69 | *qos_tid = 0; | |
70 | ||
71 | return skb->len < hdrlen ? -1 : 0; | |
72 | } | |
73 | ||
74 | ||
75 | ieee80211_txrx_result | |
76 | ieee80211_tx_h_michael_mic_add(struct ieee80211_txrx_data *tx) | |
77 | { | |
78 | u8 *data, *sa, *da, *key, *mic, qos_tid; | |
79 | size_t data_len; | |
80 | u16 fc; | |
81 | struct sk_buff *skb = tx->skb; | |
82 | int authenticator; | |
83 | int wpa_test = 0; | |
84 | ||
85 | fc = tx->fc; | |
86 | ||
87 | if (!tx->key || tx->key->alg != ALG_TKIP || skb->len < 24 || | |
88 | !WLAN_FC_DATA_PRESENT(fc)) | |
89 | return TXRX_CONTINUE; | |
90 | ||
91 | if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len)) | |
92 | return TXRX_DROP; | |
93 | ||
94 | if (!tx->key->force_sw_encrypt && | |
95 | !tx->fragmented && | |
96 | !(tx->local->hw.flags & IEEE80211_HW_TKIP_INCLUDE_MMIC) && | |
97 | !wpa_test) { | |
98 | /* hwaccel - with no need for preallocated room for Michael MIC | |
99 | */ | |
100 | return TXRX_CONTINUE; | |
101 | } | |
102 | ||
103 | if (skb_tailroom(skb) < MICHAEL_MIC_LEN) { | |
104 | I802_DEBUG_INC(tx->local->tx_expand_skb_head); | |
105 | if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN, | |
106 | MICHAEL_MIC_LEN + TKIP_ICV_LEN, | |
107 | GFP_ATOMIC))) { | |
108 | printk(KERN_DEBUG "%s: failed to allocate more memory " | |
109 | "for Michael MIC\n", tx->dev->name); | |
110 | return TXRX_DROP; | |
111 | } | |
112 | } | |
113 | ||
114 | #if 0 | |
115 | authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */ | |
116 | #else | |
117 | authenticator = 1; | |
118 | #endif | |
119 | key = &tx->key->key[authenticator ? ALG_TKIP_TEMP_AUTH_TX_MIC_KEY : | |
120 | ALG_TKIP_TEMP_AUTH_RX_MIC_KEY]; | |
121 | mic = skb_put(skb, MICHAEL_MIC_LEN); | |
122 | michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic); | |
123 | ||
124 | return TXRX_CONTINUE; | |
125 | } | |
126 | ||
127 | ||
128 | ieee80211_txrx_result | |
129 | ieee80211_rx_h_michael_mic_verify(struct ieee80211_txrx_data *rx) | |
130 | { | |
131 | u8 *data, *sa, *da, *key = NULL, qos_tid; | |
132 | size_t data_len; | |
133 | u16 fc; | |
134 | u8 mic[MICHAEL_MIC_LEN]; | |
135 | struct sk_buff *skb = rx->skb; | |
136 | int authenticator = 1, wpa_test = 0; | |
137 | ||
138 | fc = rx->fc; | |
139 | ||
140 | /* If device handles decryption totally, skip this check */ | |
141 | if ((rx->local->hw.flags & IEEE80211_HW_DEVICE_HIDES_WEP) || | |
142 | (rx->local->hw.flags & IEEE80211_HW_DEVICE_STRIPS_MIC)) | |
143 | return TXRX_CONTINUE; | |
144 | ||
145 | if (!rx->key || rx->key->alg != ALG_TKIP || | |
146 | !(rx->fc & IEEE80211_FCTL_PROTECTED) || !WLAN_FC_DATA_PRESENT(fc)) | |
147 | return TXRX_CONTINUE; | |
148 | ||
149 | if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) && | |
150 | !rx->key->force_sw_encrypt) { | |
151 | if (rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) { | |
152 | if (skb->len < MICHAEL_MIC_LEN) | |
153 | return TXRX_DROP; | |
154 | } | |
155 | /* Need to verify Michael MIC sometimes in software even when | |
156 | * hwaccel is used. Atheros ar5212: fragmented frames and QoS | |
157 | * frames. */ | |
158 | if (!rx->fragmented && !wpa_test) | |
159 | goto remove_mic; | |
160 | } | |
161 | ||
162 | if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len) | |
163 | || data_len < MICHAEL_MIC_LEN) | |
164 | return TXRX_DROP; | |
165 | ||
166 | data_len -= MICHAEL_MIC_LEN; | |
167 | ||
168 | #if 0 | |
169 | authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */ | |
170 | #else | |
171 | authenticator = 1; | |
172 | #endif | |
173 | key = &rx->key->key[authenticator ? ALG_TKIP_TEMP_AUTH_RX_MIC_KEY : | |
174 | ALG_TKIP_TEMP_AUTH_TX_MIC_KEY]; | |
175 | michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic); | |
176 | if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 || wpa_test) { | |
177 | if (!rx->u.rx.ra_match) | |
178 | return TXRX_DROP; | |
179 | ||
180 | printk(KERN_DEBUG "%s: invalid Michael MIC in data frame from " | |
181 | MAC_FMT "\n", rx->dev->name, MAC_ARG(sa)); | |
182 | ||
183 | do { | |
184 | struct ieee80211_hdr *hdr; | |
185 | union iwreq_data wrqu; | |
186 | char *buf = kmalloc(128, GFP_ATOMIC); | |
187 | if (!buf) | |
188 | break; | |
189 | ||
190 | /* TODO: needed parameters: count, key type, TSC */ | |
191 | hdr = (struct ieee80211_hdr *) skb->data; | |
192 | sprintf(buf, "MLME-MICHAELMICFAILURE.indication(" | |
193 | "keyid=%d %scast addr=" MAC_FMT ")", | |
194 | rx->key->keyidx, | |
195 | hdr->addr1[0] & 0x01 ? "broad" : "uni", | |
196 | MAC_ARG(hdr->addr2)); | |
197 | memset(&wrqu, 0, sizeof(wrqu)); | |
198 | wrqu.data.length = strlen(buf); | |
199 | wireless_send_event(rx->dev, IWEVCUSTOM, &wrqu, buf); | |
200 | kfree(buf); | |
201 | } while (0); | |
202 | ||
203 | if (!rx->local->apdev) | |
204 | return TXRX_DROP; | |
205 | ||
206 | ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status, | |
207 | ieee80211_msg_michael_mic_failure); | |
208 | ||
209 | return TXRX_QUEUED; | |
210 | } | |
211 | ||
212 | remove_mic: | |
213 | /* remove Michael MIC from payload */ | |
214 | skb_trim(skb, skb->len - MICHAEL_MIC_LEN); | |
215 | ||
216 | return TXRX_CONTINUE; | |
217 | } | |
218 | ||
219 | ||
220 | static int tkip_encrypt_skb(struct ieee80211_txrx_data *tx, | |
221 | struct sk_buff *skb, int test) | |
222 | { | |
223 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
224 | struct ieee80211_key *key = tx->key; | |
225 | int hdrlen, len, tailneed; | |
226 | u16 fc; | |
227 | u8 *pos; | |
228 | ||
229 | fc = le16_to_cpu(hdr->frame_control); | |
230 | hdrlen = ieee80211_get_hdrlen(fc); | |
231 | len = skb->len - hdrlen; | |
232 | ||
233 | tailneed = !tx->key->force_sw_encrypt ? 0 : TKIP_ICV_LEN; | |
234 | if ((skb_headroom(skb) < TKIP_IV_LEN || | |
235 | skb_tailroom(skb) < tailneed)) { | |
236 | I802_DEBUG_INC(tx->local->tx_expand_skb_head); | |
237 | if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN, tailneed, | |
238 | GFP_ATOMIC))) | |
239 | return -1; | |
240 | } | |
241 | ||
242 | pos = skb_push(skb, TKIP_IV_LEN); | |
243 | memmove(pos, pos + TKIP_IV_LEN, hdrlen); | |
244 | pos += hdrlen; | |
245 | ||
246 | /* Increase IV for the frame */ | |
247 | key->u.tkip.iv16++; | |
248 | if (key->u.tkip.iv16 == 0) | |
249 | key->u.tkip.iv32++; | |
250 | ||
251 | if (!tx->key->force_sw_encrypt) { | |
252 | u32 flags = tx->local->hw.flags; | |
253 | hdr = (struct ieee80211_hdr *)skb->data; | |
254 | ||
255 | /* hwaccel - with preallocated room for IV */ | |
256 | ieee80211_tkip_add_iv(pos, key, | |
257 | (u8) (key->u.tkip.iv16 >> 8), | |
258 | (u8) (((key->u.tkip.iv16 >> 8) | 0x20) & | |
259 | 0x7f), | |
260 | (u8) key->u.tkip.iv16); | |
261 | ||
262 | if (flags & IEEE80211_HW_TKIP_REQ_PHASE2_KEY) | |
263 | ieee80211_tkip_gen_rc4key(key, hdr->addr2, | |
264 | tx->u.tx.control->tkip_key); | |
265 | else if (flags & IEEE80211_HW_TKIP_REQ_PHASE1_KEY) { | |
266 | if (key->u.tkip.iv16 == 0 || | |
267 | !key->u.tkip.tx_initialized) { | |
268 | ieee80211_tkip_gen_phase1key(key, hdr->addr2, | |
269 | (u16 *)tx->u.tx.control->tkip_key); | |
270 | key->u.tkip.tx_initialized = 1; | |
271 | tx->u.tx.control->flags |= | |
272 | IEEE80211_TXCTL_TKIP_NEW_PHASE1_KEY; | |
273 | } else | |
274 | tx->u.tx.control->flags &= | |
275 | ~IEEE80211_TXCTL_TKIP_NEW_PHASE1_KEY; | |
276 | } | |
277 | ||
278 | tx->u.tx.control->key_idx = tx->key->hw_key_idx; | |
279 | return 0; | |
280 | } | |
281 | ||
282 | /* Add room for ICV */ | |
283 | skb_put(skb, TKIP_ICV_LEN); | |
284 | ||
285 | hdr = (struct ieee80211_hdr *) skb->data; | |
286 | ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm, | |
287 | key, pos, len, hdr->addr2); | |
288 | return 0; | |
289 | } | |
290 | ||
291 | ||
292 | ieee80211_txrx_result | |
293 | ieee80211_tx_h_tkip_encrypt(struct ieee80211_txrx_data *tx) | |
294 | { | |
295 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data; | |
296 | u16 fc; | |
297 | struct ieee80211_key *key = tx->key; | |
298 | struct sk_buff *skb = tx->skb; | |
299 | int wpa_test = 0, test = 0; | |
300 | ||
301 | fc = le16_to_cpu(hdr->frame_control); | |
302 | ||
303 | if (!key || key->alg != ALG_TKIP || !WLAN_FC_DATA_PRESENT(fc)) | |
304 | return TXRX_CONTINUE; | |
305 | ||
306 | tx->u.tx.control->icv_len = TKIP_ICV_LEN; | |
307 | tx->u.tx.control->iv_len = TKIP_IV_LEN; | |
308 | ieee80211_tx_set_iswep(tx); | |
309 | ||
310 | if (!tx->key->force_sw_encrypt && | |
311 | !(tx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) && | |
312 | !wpa_test) { | |
313 | /* hwaccel - with no need for preallocated room for IV/ICV */ | |
314 | tx->u.tx.control->key_idx = tx->key->hw_key_idx; | |
315 | return TXRX_CONTINUE; | |
316 | } | |
317 | ||
318 | if (tkip_encrypt_skb(tx, skb, test) < 0) | |
319 | return TXRX_DROP; | |
320 | ||
321 | if (tx->u.tx.extra_frag) { | |
322 | int i; | |
323 | for (i = 0; i < tx->u.tx.num_extra_frag; i++) { | |
324 | if (tkip_encrypt_skb(tx, tx->u.tx.extra_frag[i], test) | |
325 | < 0) | |
326 | return TXRX_DROP; | |
327 | } | |
328 | } | |
329 | ||
330 | return TXRX_CONTINUE; | |
331 | } | |
332 | ||
333 | ||
334 | ieee80211_txrx_result | |
335 | ieee80211_rx_h_tkip_decrypt(struct ieee80211_txrx_data *rx) | |
336 | { | |
337 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; | |
338 | u16 fc; | |
339 | int hdrlen, res, hwaccel = 0, wpa_test = 0; | |
340 | struct ieee80211_key *key = rx->key; | |
341 | struct sk_buff *skb = rx->skb; | |
342 | ||
343 | fc = le16_to_cpu(hdr->frame_control); | |
344 | hdrlen = ieee80211_get_hdrlen(fc); | |
345 | ||
346 | if (!rx->key || rx->key->alg != ALG_TKIP || | |
347 | !(rx->fc & IEEE80211_FCTL_PROTECTED) || | |
348 | (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA) | |
349 | return TXRX_CONTINUE; | |
350 | ||
351 | if (!rx->sta || skb->len - hdrlen < 12) | |
352 | return TXRX_DROP; | |
353 | ||
354 | if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) && | |
355 | !rx->key->force_sw_encrypt) { | |
356 | if (!(rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV)) { | |
357 | /* Hardware takes care of all processing, including | |
358 | * replay protection, so no need to continue here. */ | |
359 | return TXRX_CONTINUE; | |
360 | } | |
361 | ||
362 | /* let TKIP code verify IV, but skip decryption */ | |
363 | hwaccel = 1; | |
364 | } | |
365 | ||
366 | res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm, | |
367 | key, skb->data + hdrlen, | |
368 | skb->len - hdrlen, rx->sta->addr, | |
369 | hwaccel, rx->u.rx.queue); | |
370 | if (res != TKIP_DECRYPT_OK || wpa_test) { | |
371 | printk(KERN_DEBUG "%s: TKIP decrypt failed for RX frame from " | |
372 | MAC_FMT " (res=%d)\n", | |
373 | rx->dev->name, MAC_ARG(rx->sta->addr), res); | |
374 | return TXRX_DROP; | |
375 | } | |
376 | ||
377 | /* Trim ICV */ | |
378 | skb_trim(skb, skb->len - TKIP_ICV_LEN); | |
379 | ||
380 | /* Remove IV */ | |
381 | memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen); | |
382 | skb_pull(skb, TKIP_IV_LEN); | |
383 | ||
384 | return TXRX_CONTINUE; | |
385 | } | |
386 | ||
387 | ||
388 | static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad, | |
389 | int encrypted) | |
390 | { | |
391 | u16 fc; | |
392 | int a4_included, qos_included; | |
393 | u8 qos_tid, *fc_pos, *data, *sa, *da; | |
394 | int len_a; | |
395 | size_t data_len; | |
396 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
397 | ||
398 | fc_pos = (u8 *) &hdr->frame_control; | |
399 | fc = fc_pos[0] ^ (fc_pos[1] << 8); | |
400 | a4_included = (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) == | |
401 | (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS); | |
402 | ||
403 | ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len); | |
404 | data_len -= CCMP_HDR_LEN + (encrypted ? CCMP_MIC_LEN : 0); | |
405 | if (qos_tid & 0x80) { | |
406 | qos_included = 1; | |
407 | qos_tid &= 0x0f; | |
408 | } else | |
409 | qos_included = 0; | |
410 | /* First block, b_0 */ | |
411 | ||
412 | b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */ | |
413 | /* Nonce: QoS Priority | A2 | PN */ | |
414 | b_0[1] = qos_tid; | |
415 | memcpy(&b_0[2], hdr->addr2, 6); | |
416 | memcpy(&b_0[8], pn, CCMP_PN_LEN); | |
417 | /* l(m) */ | |
418 | b_0[14] = (data_len >> 8) & 0xff; | |
419 | b_0[15] = data_len & 0xff; | |
420 | ||
421 | ||
422 | /* AAD (extra authenticate-only data) / masked 802.11 header | |
423 | * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ | |
424 | ||
425 | len_a = a4_included ? 28 : 22; | |
426 | if (qos_included) | |
427 | len_a += 2; | |
428 | ||
429 | aad[0] = 0; /* (len_a >> 8) & 0xff; */ | |
430 | aad[1] = len_a & 0xff; | |
431 | /* Mask FC: zero subtype b4 b5 b6 */ | |
432 | aad[2] = fc_pos[0] & ~(BIT(4) | BIT(5) | BIT(6)); | |
433 | /* Retry, PwrMgt, MoreData; set Protected */ | |
434 | aad[3] = (fc_pos[1] & ~(BIT(3) | BIT(4) | BIT(5))) | BIT(6); | |
435 | memcpy(&aad[4], &hdr->addr1, 18); | |
436 | ||
437 | /* Mask Seq#, leave Frag# */ | |
438 | aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; | |
439 | aad[23] = 0; | |
440 | if (a4_included) { | |
441 | memcpy(&aad[24], hdr->addr4, 6); | |
442 | aad[30] = 0; | |
443 | aad[31] = 0; | |
444 | } else | |
445 | memset(&aad[24], 0, 8); | |
446 | if (qos_included) { | |
447 | u8 *dpos = &aad[a4_included ? 30 : 24]; | |
448 | ||
449 | /* Mask QoS Control field */ | |
450 | dpos[0] = qos_tid; | |
451 | dpos[1] = 0; | |
452 | } | |
453 | } | |
454 | ||
455 | ||
456 | static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) | |
457 | { | |
458 | hdr[0] = pn[5]; | |
459 | hdr[1] = pn[4]; | |
460 | hdr[2] = 0; | |
461 | hdr[3] = 0x20 | (key_id << 6); | |
462 | hdr[4] = pn[3]; | |
463 | hdr[5] = pn[2]; | |
464 | hdr[6] = pn[1]; | |
465 | hdr[7] = pn[0]; | |
466 | } | |
467 | ||
468 | ||
469 | static inline int ccmp_hdr2pn(u8 *pn, u8 *hdr) | |
470 | { | |
471 | pn[0] = hdr[7]; | |
472 | pn[1] = hdr[6]; | |
473 | pn[2] = hdr[5]; | |
474 | pn[3] = hdr[4]; | |
475 | pn[4] = hdr[1]; | |
476 | pn[5] = hdr[0]; | |
477 | return (hdr[3] >> 6) & 0x03; | |
478 | } | |
479 | ||
480 | ||
481 | static int ccmp_encrypt_skb(struct ieee80211_txrx_data *tx, | |
482 | struct sk_buff *skb, int test) | |
483 | { | |
484 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
485 | struct ieee80211_key *key = tx->key; | |
486 | int hdrlen, len, tailneed; | |
487 | u16 fc; | |
488 | u8 *pos, *pn, *b_0, *aad, *scratch; | |
489 | int i; | |
490 | ||
491 | scratch = key->u.ccmp.tx_crypto_buf; | |
492 | b_0 = scratch + 3 * AES_BLOCK_LEN; | |
493 | aad = scratch + 4 * AES_BLOCK_LEN; | |
494 | ||
495 | fc = le16_to_cpu(hdr->frame_control); | |
496 | hdrlen = ieee80211_get_hdrlen(fc); | |
497 | len = skb->len - hdrlen; | |
498 | ||
499 | tailneed = !key->force_sw_encrypt ? 0 : CCMP_MIC_LEN; | |
500 | ||
501 | if ((skb_headroom(skb) < CCMP_HDR_LEN || | |
502 | skb_tailroom(skb) < tailneed)) { | |
503 | I802_DEBUG_INC(tx->local->tx_expand_skb_head); | |
504 | if (unlikely(pskb_expand_head(skb, CCMP_HDR_LEN, tailneed, | |
505 | GFP_ATOMIC))) | |
506 | return -1; | |
507 | } | |
508 | ||
509 | pos = skb_push(skb, CCMP_HDR_LEN); | |
510 | memmove(pos, pos + CCMP_HDR_LEN, hdrlen); | |
511 | hdr = (struct ieee80211_hdr *) pos; | |
512 | pos += hdrlen; | |
513 | ||
514 | /* PN = PN + 1 */ | |
515 | pn = key->u.ccmp.tx_pn; | |
516 | ||
517 | for (i = CCMP_PN_LEN - 1; i >= 0; i--) { | |
518 | pn[i]++; | |
519 | if (pn[i]) | |
520 | break; | |
521 | } | |
522 | ||
523 | ccmp_pn2hdr(pos, pn, key->keyidx); | |
524 | ||
525 | if (!key->force_sw_encrypt) { | |
526 | /* hwaccel - with preallocated room for CCMP header */ | |
527 | tx->u.tx.control->key_idx = key->hw_key_idx; | |
528 | return 0; | |
529 | } | |
530 | ||
531 | pos += CCMP_HDR_LEN; | |
532 | ccmp_special_blocks(skb, pn, b_0, aad, 0); | |
533 | ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, b_0, aad, pos, len, | |
534 | pos, skb_put(skb, CCMP_MIC_LEN)); | |
535 | ||
536 | return 0; | |
537 | } | |
538 | ||
539 | ||
540 | ieee80211_txrx_result | |
541 | ieee80211_tx_h_ccmp_encrypt(struct ieee80211_txrx_data *tx) | |
542 | { | |
543 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data; | |
544 | struct ieee80211_key *key = tx->key; | |
545 | u16 fc; | |
546 | struct sk_buff *skb = tx->skb; | |
547 | int test = 0; | |
548 | ||
549 | fc = le16_to_cpu(hdr->frame_control); | |
550 | ||
551 | if (!key || key->alg != ALG_CCMP || !WLAN_FC_DATA_PRESENT(fc)) | |
552 | return TXRX_CONTINUE; | |
553 | ||
554 | tx->u.tx.control->icv_len = CCMP_MIC_LEN; | |
555 | tx->u.tx.control->iv_len = CCMP_HDR_LEN; | |
556 | ieee80211_tx_set_iswep(tx); | |
557 | ||
558 | if (!tx->key->force_sw_encrypt && | |
559 | !(tx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV)) { | |
560 | /* hwaccel - with no need for preallocated room for CCMP " | |
561 | * header or MIC fields */ | |
562 | tx->u.tx.control->key_idx = tx->key->hw_key_idx; | |
563 | return TXRX_CONTINUE; | |
564 | } | |
565 | ||
566 | if (ccmp_encrypt_skb(tx, skb, test) < 0) | |
567 | return TXRX_DROP; | |
568 | ||
569 | if (tx->u.tx.extra_frag) { | |
570 | int i; | |
571 | ||
572 | for (i = 0; i < tx->u.tx.num_extra_frag; i++) { | |
573 | if (ccmp_encrypt_skb(tx, tx->u.tx.extra_frag[i], test) | |
574 | < 0) | |
575 | return TXRX_DROP; | |
576 | } | |
577 | } | |
578 | ||
579 | return TXRX_CONTINUE; | |
580 | } | |
581 | ||
582 | ||
583 | ieee80211_txrx_result | |
584 | ieee80211_rx_h_ccmp_decrypt(struct ieee80211_txrx_data *rx) | |
585 | { | |
586 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; | |
587 | u16 fc; | |
588 | int hdrlen; | |
589 | struct ieee80211_key *key = rx->key; | |
590 | struct sk_buff *skb = rx->skb; | |
591 | u8 pn[CCMP_PN_LEN]; | |
592 | int data_len; | |
593 | ||
594 | fc = le16_to_cpu(hdr->frame_control); | |
595 | hdrlen = ieee80211_get_hdrlen(fc); | |
596 | ||
597 | if (!key || key->alg != ALG_CCMP || | |
598 | !(rx->fc & IEEE80211_FCTL_PROTECTED) || | |
599 | (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA) | |
600 | return TXRX_CONTINUE; | |
601 | ||
602 | data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN; | |
603 | if (!rx->sta || data_len < 0) | |
604 | return TXRX_DROP; | |
605 | ||
606 | if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) && | |
607 | !key->force_sw_encrypt && | |
608 | !(rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV)) | |
609 | return TXRX_CONTINUE; | |
610 | ||
611 | (void) ccmp_hdr2pn(pn, skb->data + hdrlen); | |
612 | ||
613 | if (memcmp(pn, key->u.ccmp.rx_pn[rx->u.rx.queue], CCMP_PN_LEN) <= 0) { | |
614 | #ifdef CONFIG_MAC80211_DEBUG | |
615 | u8 *ppn = key->u.ccmp.rx_pn[rx->u.rx.queue]; | |
616 | printk(KERN_DEBUG "%s: CCMP replay detected for RX frame from " | |
617 | MAC_FMT " (RX PN %02x%02x%02x%02x%02x%02x <= prev. PN " | |
618 | "%02x%02x%02x%02x%02x%02x)\n", rx->dev->name, | |
619 | MAC_ARG(rx->sta->addr), | |
620 | pn[0], pn[1], pn[2], pn[3], pn[4], pn[5], | |
621 | ppn[0], ppn[1], ppn[2], ppn[3], ppn[4], ppn[5]); | |
622 | #endif /* CONFIG_MAC80211_DEBUG */ | |
623 | key->u.ccmp.replays++; | |
624 | return TXRX_DROP; | |
625 | } | |
626 | ||
627 | if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) && | |
628 | !key->force_sw_encrypt) { | |
629 | /* hwaccel has already decrypted frame and verified MIC */ | |
630 | } else { | |
631 | u8 *scratch, *b_0, *aad; | |
632 | ||
633 | scratch = key->u.ccmp.rx_crypto_buf; | |
634 | b_0 = scratch + 3 * AES_BLOCK_LEN; | |
635 | aad = scratch + 4 * AES_BLOCK_LEN; | |
636 | ||
637 | ccmp_special_blocks(skb, pn, b_0, aad, 1); | |
638 | ||
639 | if (ieee80211_aes_ccm_decrypt( | |
640 | key->u.ccmp.tfm, scratch, b_0, aad, | |
641 | skb->data + hdrlen + CCMP_HDR_LEN, data_len, | |
642 | skb->data + skb->len - CCMP_MIC_LEN, | |
643 | skb->data + hdrlen + CCMP_HDR_LEN)) { | |
644 | printk(KERN_DEBUG "%s: CCMP decrypt failed for RX " | |
645 | "frame from " MAC_FMT "\n", rx->dev->name, | |
646 | MAC_ARG(rx->sta->addr)); | |
647 | return TXRX_DROP; | |
648 | } | |
649 | } | |
650 | ||
651 | memcpy(key->u.ccmp.rx_pn[rx->u.rx.queue], pn, CCMP_PN_LEN); | |
652 | ||
653 | /* Remove CCMP header and MIC */ | |
654 | skb_trim(skb, skb->len - CCMP_MIC_LEN); | |
655 | memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen); | |
656 | skb_pull(skb, CCMP_HDR_LEN); | |
657 | ||
658 | return TXRX_CONTINUE; | |
659 | } | |
660 |