Commit | Line | Data |
---|---|---|
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> | |
f0706e82 | 14 | #include <net/mac80211.h> |
eb063c17 | 15 | |
f0706e82 JB |
16 | #include "ieee80211_i.h" |
17 | #include "michael.h" | |
18 | #include "tkip.h" | |
19 | #include "aes_ccm.h" | |
20 | #include "wpa.h" | |
21 | ||
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) | |
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 | ||
73 | ieee80211_txrx_result | |
74 | ieee80211_tx_h_michael_mic_add(struct ieee80211_txrx_data *tx) | |
75 | { | |
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 | ||
85 | if (!tx->key || tx->key->alg != ALG_TKIP || skb->len < 24 || | |
86 | !WLAN_FC_DATA_PRESENT(fc)) | |
87 | return TXRX_CONTINUE; | |
88 | ||
89 | if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len)) | |
90 | return TXRX_DROP; | |
91 | ||
92 | if (!tx->key->force_sw_encrypt && | |
badffb72 | 93 | !(tx->flags & IEEE80211_TXRXD_FRAGMENTED) && |
f0706e82 JB |
94 | !(tx->local->hw.flags & IEEE80211_HW_TKIP_INCLUDE_MMIC) && |
95 | !wpa_test) { | |
96 | /* hwaccel - with no need for preallocated room for Michael MIC | |
97 | */ | |
98 | return TXRX_CONTINUE; | |
99 | } | |
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); | |
108 | return TXRX_DROP; | |
109 | } | |
110 | } | |
111 | ||
112 | #if 0 | |
113 | authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */ | |
114 | #else | |
115 | authenticator = 1; | |
116 | #endif | |
117 | key = &tx->key->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); | |
121 | ||
122 | return TXRX_CONTINUE; | |
123 | } | |
124 | ||
125 | ||
126 | ieee80211_txrx_result | |
127 | ieee80211_rx_h_michael_mic_verify(struct ieee80211_txrx_data *rx) | |
128 | { | |
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; | |
135 | ||
136 | fc = rx->fc; | |
137 | ||
3017b80b JB |
138 | /* |
139 | * No way to verify the MIC if the hardware stripped it | |
140 | */ | |
141 | if (rx->local->hw.flags & IEEE80211_HW_DEVICE_STRIPS_MIC) | |
f0706e82 JB |
142 | return TXRX_CONTINUE; |
143 | ||
144 | if (!rx->key || rx->key->alg != ALG_TKIP || | |
145 | !(rx->fc & IEEE80211_FCTL_PROTECTED) || !WLAN_FC_DATA_PRESENT(fc)) | |
146 | return TXRX_CONTINUE; | |
147 | ||
148 | if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) && | |
149 | !rx->key->force_sw_encrypt) { | |
150 | if (rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) { | |
151 | if (skb->len < MICHAEL_MIC_LEN) | |
152 | return TXRX_DROP; | |
153 | } | |
154 | /* Need to verify Michael MIC sometimes in software even when | |
155 | * hwaccel is used. Atheros ar5212: fragmented frames and QoS | |
156 | * frames. */ | |
badffb72 | 157 | if (!(rx->flags & IEEE80211_TXRXD_FRAGMENTED) && !wpa_test) |
f0706e82 JB |
158 | goto remove_mic; |
159 | } | |
160 | ||
161 | if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len) | |
162 | || data_len < MICHAEL_MIC_LEN) | |
163 | return TXRX_DROP; | |
164 | ||
165 | data_len -= MICHAEL_MIC_LEN; | |
166 | ||
167 | #if 0 | |
168 | authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */ | |
169 | #else | |
170 | authenticator = 1; | |
171 | #endif | |
172 | key = &rx->key->key[authenticator ? ALG_TKIP_TEMP_AUTH_RX_MIC_KEY : | |
173 | ALG_TKIP_TEMP_AUTH_TX_MIC_KEY]; | |
174 | michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic); | |
175 | if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 || wpa_test) { | |
badffb72 | 176 | if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) |
f0706e82 JB |
177 | return TXRX_DROP; |
178 | ||
179 | printk(KERN_DEBUG "%s: invalid Michael MIC in data frame from " | |
180 | MAC_FMT "\n", rx->dev->name, MAC_ARG(sa)); | |
181 | ||
eb063c17 JB |
182 | mac80211_ev_michael_mic_failure(rx->dev, rx->key->keyidx, |
183 | (void *) skb->data); | |
184 | return TXRX_DROP; | |
f0706e82 JB |
185 | } |
186 | ||
187 | remove_mic: | |
188 | /* remove Michael MIC from payload */ | |
189 | skb_trim(skb, skb->len - MICHAEL_MIC_LEN); | |
190 | ||
191 | return TXRX_CONTINUE; | |
192 | } | |
193 | ||
194 | ||
195 | static int tkip_encrypt_skb(struct ieee80211_txrx_data *tx, | |
196 | struct sk_buff *skb, int test) | |
197 | { | |
198 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
199 | struct ieee80211_key *key = tx->key; | |
200 | int hdrlen, len, tailneed; | |
201 | u16 fc; | |
202 | u8 *pos; | |
203 | ||
204 | fc = le16_to_cpu(hdr->frame_control); | |
205 | hdrlen = ieee80211_get_hdrlen(fc); | |
206 | len = skb->len - hdrlen; | |
207 | ||
208 | tailneed = !tx->key->force_sw_encrypt ? 0 : TKIP_ICV_LEN; | |
209 | if ((skb_headroom(skb) < TKIP_IV_LEN || | |
210 | skb_tailroom(skb) < tailneed)) { | |
211 | I802_DEBUG_INC(tx->local->tx_expand_skb_head); | |
212 | if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN, tailneed, | |
213 | GFP_ATOMIC))) | |
214 | return -1; | |
215 | } | |
216 | ||
217 | pos = skb_push(skb, TKIP_IV_LEN); | |
218 | memmove(pos, pos + TKIP_IV_LEN, hdrlen); | |
219 | pos += hdrlen; | |
220 | ||
221 | /* Increase IV for the frame */ | |
222 | key->u.tkip.iv16++; | |
223 | if (key->u.tkip.iv16 == 0) | |
224 | key->u.tkip.iv32++; | |
225 | ||
226 | if (!tx->key->force_sw_encrypt) { | |
227 | u32 flags = tx->local->hw.flags; | |
228 | hdr = (struct ieee80211_hdr *)skb->data; | |
229 | ||
230 | /* hwaccel - with preallocated room for IV */ | |
231 | ieee80211_tkip_add_iv(pos, key, | |
232 | (u8) (key->u.tkip.iv16 >> 8), | |
233 | (u8) (((key->u.tkip.iv16 >> 8) | 0x20) & | |
234 | 0x7f), | |
235 | (u8) key->u.tkip.iv16); | |
236 | ||
237 | if (flags & IEEE80211_HW_TKIP_REQ_PHASE2_KEY) | |
238 | ieee80211_tkip_gen_rc4key(key, hdr->addr2, | |
239 | tx->u.tx.control->tkip_key); | |
240 | else if (flags & IEEE80211_HW_TKIP_REQ_PHASE1_KEY) { | |
241 | if (key->u.tkip.iv16 == 0 || | |
242 | !key->u.tkip.tx_initialized) { | |
243 | ieee80211_tkip_gen_phase1key(key, hdr->addr2, | |
244 | (u16 *)tx->u.tx.control->tkip_key); | |
245 | key->u.tkip.tx_initialized = 1; | |
246 | tx->u.tx.control->flags |= | |
247 | IEEE80211_TXCTL_TKIP_NEW_PHASE1_KEY; | |
248 | } else | |
249 | tx->u.tx.control->flags &= | |
250 | ~IEEE80211_TXCTL_TKIP_NEW_PHASE1_KEY; | |
251 | } | |
252 | ||
253 | tx->u.tx.control->key_idx = tx->key->hw_key_idx; | |
254 | return 0; | |
255 | } | |
256 | ||
257 | /* Add room for ICV */ | |
258 | skb_put(skb, TKIP_ICV_LEN); | |
259 | ||
260 | hdr = (struct ieee80211_hdr *) skb->data; | |
261 | ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm, | |
262 | key, pos, len, hdr->addr2); | |
263 | return 0; | |
264 | } | |
265 | ||
266 | ||
267 | ieee80211_txrx_result | |
268 | ieee80211_tx_h_tkip_encrypt(struct ieee80211_txrx_data *tx) | |
269 | { | |
270 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data; | |
271 | u16 fc; | |
272 | struct ieee80211_key *key = tx->key; | |
273 | struct sk_buff *skb = tx->skb; | |
274 | int wpa_test = 0, test = 0; | |
275 | ||
276 | fc = le16_to_cpu(hdr->frame_control); | |
277 | ||
278 | if (!key || key->alg != ALG_TKIP || !WLAN_FC_DATA_PRESENT(fc)) | |
279 | return TXRX_CONTINUE; | |
280 | ||
281 | tx->u.tx.control->icv_len = TKIP_ICV_LEN; | |
282 | tx->u.tx.control->iv_len = TKIP_IV_LEN; | |
283 | ieee80211_tx_set_iswep(tx); | |
284 | ||
285 | if (!tx->key->force_sw_encrypt && | |
286 | !(tx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) && | |
287 | !wpa_test) { | |
288 | /* hwaccel - with no need for preallocated room for IV/ICV */ | |
289 | tx->u.tx.control->key_idx = tx->key->hw_key_idx; | |
290 | return TXRX_CONTINUE; | |
291 | } | |
292 | ||
293 | if (tkip_encrypt_skb(tx, skb, test) < 0) | |
294 | return TXRX_DROP; | |
295 | ||
296 | if (tx->u.tx.extra_frag) { | |
297 | int i; | |
298 | for (i = 0; i < tx->u.tx.num_extra_frag; i++) { | |
299 | if (tkip_encrypt_skb(tx, tx->u.tx.extra_frag[i], test) | |
300 | < 0) | |
301 | return TXRX_DROP; | |
302 | } | |
303 | } | |
304 | ||
305 | return TXRX_CONTINUE; | |
306 | } | |
307 | ||
308 | ||
309 | ieee80211_txrx_result | |
310 | ieee80211_rx_h_tkip_decrypt(struct ieee80211_txrx_data *rx) | |
311 | { | |
312 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; | |
313 | u16 fc; | |
314 | int hdrlen, res, hwaccel = 0, wpa_test = 0; | |
315 | struct ieee80211_key *key = rx->key; | |
316 | struct sk_buff *skb = rx->skb; | |
317 | ||
318 | fc = le16_to_cpu(hdr->frame_control); | |
319 | hdrlen = ieee80211_get_hdrlen(fc); | |
320 | ||
321 | if (!rx->key || rx->key->alg != ALG_TKIP || | |
322 | !(rx->fc & IEEE80211_FCTL_PROTECTED) || | |
323 | (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA) | |
324 | return TXRX_CONTINUE; | |
325 | ||
326 | if (!rx->sta || skb->len - hdrlen < 12) | |
327 | return TXRX_DROP; | |
328 | ||
329 | if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) && | |
330 | !rx->key->force_sw_encrypt) { | |
331 | if (!(rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV)) { | |
332 | /* Hardware takes care of all processing, including | |
333 | * replay protection, so no need to continue here. */ | |
334 | return TXRX_CONTINUE; | |
335 | } | |
336 | ||
337 | /* let TKIP code verify IV, but skip decryption */ | |
338 | hwaccel = 1; | |
339 | } | |
340 | ||
341 | res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm, | |
342 | key, skb->data + hdrlen, | |
343 | skb->len - hdrlen, rx->sta->addr, | |
344 | hwaccel, rx->u.rx.queue); | |
345 | if (res != TKIP_DECRYPT_OK || wpa_test) { | |
346 | printk(KERN_DEBUG "%s: TKIP decrypt failed for RX frame from " | |
347 | MAC_FMT " (res=%d)\n", | |
348 | rx->dev->name, MAC_ARG(rx->sta->addr), res); | |
349 | return TXRX_DROP; | |
350 | } | |
351 | ||
352 | /* Trim ICV */ | |
353 | skb_trim(skb, skb->len - TKIP_ICV_LEN); | |
354 | ||
355 | /* Remove IV */ | |
356 | memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen); | |
357 | skb_pull(skb, TKIP_IV_LEN); | |
358 | ||
359 | return TXRX_CONTINUE; | |
360 | } | |
361 | ||
362 | ||
363 | static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad, | |
364 | int encrypted) | |
365 | { | |
366 | u16 fc; | |
367 | int a4_included, qos_included; | |
368 | u8 qos_tid, *fc_pos, *data, *sa, *da; | |
369 | int len_a; | |
370 | size_t data_len; | |
371 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
372 | ||
373 | fc_pos = (u8 *) &hdr->frame_control; | |
374 | fc = fc_pos[0] ^ (fc_pos[1] << 8); | |
375 | a4_included = (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) == | |
376 | (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS); | |
377 | ||
378 | ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len); | |
379 | data_len -= CCMP_HDR_LEN + (encrypted ? CCMP_MIC_LEN : 0); | |
380 | if (qos_tid & 0x80) { | |
381 | qos_included = 1; | |
382 | qos_tid &= 0x0f; | |
383 | } else | |
384 | qos_included = 0; | |
385 | /* First block, b_0 */ | |
386 | ||
387 | b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */ | |
388 | /* Nonce: QoS Priority | A2 | PN */ | |
389 | b_0[1] = qos_tid; | |
390 | memcpy(&b_0[2], hdr->addr2, 6); | |
391 | memcpy(&b_0[8], pn, CCMP_PN_LEN); | |
392 | /* l(m) */ | |
393 | b_0[14] = (data_len >> 8) & 0xff; | |
394 | b_0[15] = data_len & 0xff; | |
395 | ||
396 | ||
397 | /* AAD (extra authenticate-only data) / masked 802.11 header | |
398 | * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ | |
399 | ||
400 | len_a = a4_included ? 28 : 22; | |
401 | if (qos_included) | |
402 | len_a += 2; | |
403 | ||
404 | aad[0] = 0; /* (len_a >> 8) & 0xff; */ | |
405 | aad[1] = len_a & 0xff; | |
406 | /* Mask FC: zero subtype b4 b5 b6 */ | |
407 | aad[2] = fc_pos[0] & ~(BIT(4) | BIT(5) | BIT(6)); | |
408 | /* Retry, PwrMgt, MoreData; set Protected */ | |
409 | aad[3] = (fc_pos[1] & ~(BIT(3) | BIT(4) | BIT(5))) | BIT(6); | |
410 | memcpy(&aad[4], &hdr->addr1, 18); | |
411 | ||
412 | /* Mask Seq#, leave Frag# */ | |
413 | aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; | |
414 | aad[23] = 0; | |
415 | if (a4_included) { | |
416 | memcpy(&aad[24], hdr->addr4, 6); | |
417 | aad[30] = 0; | |
418 | aad[31] = 0; | |
419 | } else | |
420 | memset(&aad[24], 0, 8); | |
421 | if (qos_included) { | |
422 | u8 *dpos = &aad[a4_included ? 30 : 24]; | |
423 | ||
424 | /* Mask QoS Control field */ | |
425 | dpos[0] = qos_tid; | |
426 | dpos[1] = 0; | |
427 | } | |
428 | } | |
429 | ||
430 | ||
431 | static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) | |
432 | { | |
433 | hdr[0] = pn[5]; | |
434 | hdr[1] = pn[4]; | |
435 | hdr[2] = 0; | |
436 | hdr[3] = 0x20 | (key_id << 6); | |
437 | hdr[4] = pn[3]; | |
438 | hdr[5] = pn[2]; | |
439 | hdr[6] = pn[1]; | |
440 | hdr[7] = pn[0]; | |
441 | } | |
442 | ||
443 | ||
444 | static inline int ccmp_hdr2pn(u8 *pn, u8 *hdr) | |
445 | { | |
446 | pn[0] = hdr[7]; | |
447 | pn[1] = hdr[6]; | |
448 | pn[2] = hdr[5]; | |
449 | pn[3] = hdr[4]; | |
450 | pn[4] = hdr[1]; | |
451 | pn[5] = hdr[0]; | |
452 | return (hdr[3] >> 6) & 0x03; | |
453 | } | |
454 | ||
455 | ||
456 | static int ccmp_encrypt_skb(struct ieee80211_txrx_data *tx, | |
457 | struct sk_buff *skb, int test) | |
458 | { | |
459 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
460 | struct ieee80211_key *key = tx->key; | |
461 | int hdrlen, len, tailneed; | |
462 | u16 fc; | |
463 | u8 *pos, *pn, *b_0, *aad, *scratch; | |
464 | int i; | |
465 | ||
466 | scratch = key->u.ccmp.tx_crypto_buf; | |
467 | b_0 = scratch + 3 * AES_BLOCK_LEN; | |
468 | aad = scratch + 4 * AES_BLOCK_LEN; | |
469 | ||
470 | fc = le16_to_cpu(hdr->frame_control); | |
471 | hdrlen = ieee80211_get_hdrlen(fc); | |
472 | len = skb->len - hdrlen; | |
473 | ||
474 | tailneed = !key->force_sw_encrypt ? 0 : CCMP_MIC_LEN; | |
475 | ||
476 | if ((skb_headroom(skb) < CCMP_HDR_LEN || | |
477 | skb_tailroom(skb) < tailneed)) { | |
478 | I802_DEBUG_INC(tx->local->tx_expand_skb_head); | |
479 | if (unlikely(pskb_expand_head(skb, CCMP_HDR_LEN, tailneed, | |
480 | GFP_ATOMIC))) | |
481 | return -1; | |
482 | } | |
483 | ||
484 | pos = skb_push(skb, CCMP_HDR_LEN); | |
485 | memmove(pos, pos + CCMP_HDR_LEN, hdrlen); | |
486 | hdr = (struct ieee80211_hdr *) pos; | |
487 | pos += hdrlen; | |
488 | ||
489 | /* PN = PN + 1 */ | |
490 | pn = key->u.ccmp.tx_pn; | |
491 | ||
492 | for (i = CCMP_PN_LEN - 1; i >= 0; i--) { | |
493 | pn[i]++; | |
494 | if (pn[i]) | |
495 | break; | |
496 | } | |
497 | ||
498 | ccmp_pn2hdr(pos, pn, key->keyidx); | |
499 | ||
500 | if (!key->force_sw_encrypt) { | |
501 | /* hwaccel - with preallocated room for CCMP header */ | |
502 | tx->u.tx.control->key_idx = key->hw_key_idx; | |
503 | return 0; | |
504 | } | |
505 | ||
506 | pos += CCMP_HDR_LEN; | |
507 | ccmp_special_blocks(skb, pn, b_0, aad, 0); | |
508 | ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, b_0, aad, pos, len, | |
509 | pos, skb_put(skb, CCMP_MIC_LEN)); | |
510 | ||
511 | return 0; | |
512 | } | |
513 | ||
514 | ||
515 | ieee80211_txrx_result | |
516 | ieee80211_tx_h_ccmp_encrypt(struct ieee80211_txrx_data *tx) | |
517 | { | |
518 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data; | |
519 | struct ieee80211_key *key = tx->key; | |
520 | u16 fc; | |
521 | struct sk_buff *skb = tx->skb; | |
522 | int test = 0; | |
523 | ||
524 | fc = le16_to_cpu(hdr->frame_control); | |
525 | ||
526 | if (!key || key->alg != ALG_CCMP || !WLAN_FC_DATA_PRESENT(fc)) | |
527 | return TXRX_CONTINUE; | |
528 | ||
529 | tx->u.tx.control->icv_len = CCMP_MIC_LEN; | |
530 | tx->u.tx.control->iv_len = CCMP_HDR_LEN; | |
531 | ieee80211_tx_set_iswep(tx); | |
532 | ||
533 | if (!tx->key->force_sw_encrypt && | |
534 | !(tx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV)) { | |
535 | /* hwaccel - with no need for preallocated room for CCMP " | |
536 | * header or MIC fields */ | |
537 | tx->u.tx.control->key_idx = tx->key->hw_key_idx; | |
538 | return TXRX_CONTINUE; | |
539 | } | |
540 | ||
541 | if (ccmp_encrypt_skb(tx, skb, test) < 0) | |
542 | return TXRX_DROP; | |
543 | ||
544 | if (tx->u.tx.extra_frag) { | |
545 | int i; | |
546 | ||
547 | for (i = 0; i < tx->u.tx.num_extra_frag; i++) { | |
548 | if (ccmp_encrypt_skb(tx, tx->u.tx.extra_frag[i], test) | |
549 | < 0) | |
550 | return TXRX_DROP; | |
551 | } | |
552 | } | |
553 | ||
554 | return TXRX_CONTINUE; | |
555 | } | |
556 | ||
557 | ||
558 | ieee80211_txrx_result | |
559 | ieee80211_rx_h_ccmp_decrypt(struct ieee80211_txrx_data *rx) | |
560 | { | |
561 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; | |
562 | u16 fc; | |
563 | int hdrlen; | |
564 | struct ieee80211_key *key = rx->key; | |
565 | struct sk_buff *skb = rx->skb; | |
566 | u8 pn[CCMP_PN_LEN]; | |
567 | int data_len; | |
568 | ||
569 | fc = le16_to_cpu(hdr->frame_control); | |
570 | hdrlen = ieee80211_get_hdrlen(fc); | |
571 | ||
572 | if (!key || key->alg != ALG_CCMP || | |
573 | !(rx->fc & IEEE80211_FCTL_PROTECTED) || | |
574 | (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA) | |
575 | return TXRX_CONTINUE; | |
576 | ||
577 | data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN; | |
578 | if (!rx->sta || data_len < 0) | |
579 | return TXRX_DROP; | |
580 | ||
581 | if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) && | |
582 | !key->force_sw_encrypt && | |
583 | !(rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV)) | |
584 | return TXRX_CONTINUE; | |
585 | ||
586 | (void) ccmp_hdr2pn(pn, skb->data + hdrlen); | |
587 | ||
588 | if (memcmp(pn, key->u.ccmp.rx_pn[rx->u.rx.queue], CCMP_PN_LEN) <= 0) { | |
589 | #ifdef CONFIG_MAC80211_DEBUG | |
590 | u8 *ppn = key->u.ccmp.rx_pn[rx->u.rx.queue]; | |
591 | printk(KERN_DEBUG "%s: CCMP replay detected for RX frame from " | |
592 | MAC_FMT " (RX PN %02x%02x%02x%02x%02x%02x <= prev. PN " | |
593 | "%02x%02x%02x%02x%02x%02x)\n", rx->dev->name, | |
594 | MAC_ARG(rx->sta->addr), | |
595 | pn[0], pn[1], pn[2], pn[3], pn[4], pn[5], | |
596 | ppn[0], ppn[1], ppn[2], ppn[3], ppn[4], ppn[5]); | |
597 | #endif /* CONFIG_MAC80211_DEBUG */ | |
598 | key->u.ccmp.replays++; | |
599 | return TXRX_DROP; | |
600 | } | |
601 | ||
602 | if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) && | |
603 | !key->force_sw_encrypt) { | |
604 | /* hwaccel has already decrypted frame and verified MIC */ | |
605 | } else { | |
606 | u8 *scratch, *b_0, *aad; | |
607 | ||
608 | scratch = key->u.ccmp.rx_crypto_buf; | |
609 | b_0 = scratch + 3 * AES_BLOCK_LEN; | |
610 | aad = scratch + 4 * AES_BLOCK_LEN; | |
611 | ||
612 | ccmp_special_blocks(skb, pn, b_0, aad, 1); | |
613 | ||
614 | if (ieee80211_aes_ccm_decrypt( | |
615 | key->u.ccmp.tfm, scratch, b_0, aad, | |
616 | skb->data + hdrlen + CCMP_HDR_LEN, data_len, | |
617 | skb->data + skb->len - CCMP_MIC_LEN, | |
618 | skb->data + hdrlen + CCMP_HDR_LEN)) { | |
619 | printk(KERN_DEBUG "%s: CCMP decrypt failed for RX " | |
620 | "frame from " MAC_FMT "\n", rx->dev->name, | |
621 | MAC_ARG(rx->sta->addr)); | |
622 | return TXRX_DROP; | |
623 | } | |
624 | } | |
625 | ||
626 | memcpy(key->u.ccmp.rx_pn[rx->u.rx.queue], pn, CCMP_PN_LEN); | |
627 | ||
628 | /* Remove CCMP header and MIC */ | |
629 | skb_trim(skb, skb->len - CCMP_MIC_LEN); | |
630 | memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen); | |
631 | skb_pull(skb, CCMP_HDR_LEN); | |
632 | ||
633 | return TXRX_CONTINUE; | |
634 | } | |
635 |