Commit | Line | Data |
---|---|---|
f0706e82 JB |
1 | /* |
2 | * Copyright 2002-2004, Instant802 Networks, Inc. | |
765cb46a | 3 | * Copyright 2008, Jouni Malinen <j@w1.fi> |
f0706e82 JB |
4 | * |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License version 2 as | |
7 | * published by the Free Software Foundation. | |
8 | */ | |
9 | ||
10 | #include <linux/netdevice.h> | |
11 | #include <linux/types.h> | |
12 | #include <linux/slab.h> | |
13 | #include <linux/skbuff.h> | |
14 | #include <linux/compiler.h> | |
f14df804 HH |
15 | #include <linux/ieee80211.h> |
16 | #include <asm/unaligned.h> | |
f0706e82 | 17 | #include <net/mac80211.h> |
eb063c17 | 18 | |
f0706e82 JB |
19 | #include "ieee80211_i.h" |
20 | #include "michael.h" | |
21 | #include "tkip.h" | |
22 | #include "aes_ccm.h" | |
765cb46a | 23 | #include "aes_cmac.h" |
f0706e82 JB |
24 | #include "wpa.h" |
25 | ||
9ae54c84 | 26 | ieee80211_tx_result |
5cf121c3 | 27 | ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx) |
f0706e82 | 28 | { |
8e8862b7 | 29 | u8 *data, *key, *mic, key_offset; |
f0706e82 | 30 | size_t data_len; |
8e8862b7 HH |
31 | unsigned int hdrlen; |
32 | struct ieee80211_hdr *hdr; | |
f0706e82 JB |
33 | struct sk_buff *skb = tx->skb; |
34 | int authenticator; | |
35 | int wpa_test = 0; | |
23c0752a | 36 | int tail; |
f0706e82 | 37 | |
c34498b9 | 38 | hdr = (struct ieee80211_hdr *)skb->data; |
8f20fc24 | 39 | if (!tx->key || tx->key->conf.alg != ALG_TKIP || skb->len < 24 || |
c34498b9 | 40 | !ieee80211_is_data_present(hdr->frame_control)) |
9ae54c84 | 41 | return TX_CONTINUE; |
f0706e82 | 42 | |
8e8862b7 HH |
43 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
44 | if (skb->len < hdrlen) | |
9ae54c84 | 45 | return TX_DROP; |
f0706e82 | 46 | |
8e8862b7 HH |
47 | data = skb->data + hdrlen; |
48 | data_len = skb->len - hdrlen; | |
49 | ||
11a843b7 | 50 | if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && |
5cf121c3 | 51 | !(tx->flags & IEEE80211_TX_FRAGMENTED) && |
7848ba7d | 52 | !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) && |
f0706e82 | 53 | !wpa_test) { |
c6a1fa12 | 54 | /* hwaccel - with no need for preallocated room for MMIC */ |
9ae54c84 | 55 | return TX_CONTINUE; |
f0706e82 JB |
56 | } |
57 | ||
23c0752a JB |
58 | tail = MICHAEL_MIC_LEN; |
59 | if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) | |
60 | tail += TKIP_ICV_LEN; | |
61 | ||
62 | if (WARN_ON(skb_tailroom(skb) < tail || | |
63 | skb_headroom(skb) < TKIP_IV_LEN)) | |
64 | return TX_DROP; | |
f0706e82 JB |
65 | |
66 | #if 0 | |
67 | authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */ | |
68 | #else | |
69 | authenticator = 1; | |
70 | #endif | |
ffd7891d LR |
71 | key_offset = authenticator ? |
72 | NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY : | |
73 | NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY; | |
74 | key = &tx->key->conf.key[key_offset]; | |
f0706e82 | 75 | mic = skb_put(skb, MICHAEL_MIC_LEN); |
8e8862b7 | 76 | michael_mic(key, hdr, data, data_len, mic); |
f0706e82 | 77 | |
9ae54c84 | 78 | return TX_CONTINUE; |
f0706e82 JB |
79 | } |
80 | ||
81 | ||
9ae54c84 | 82 | ieee80211_rx_result |
5cf121c3 | 83 | ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) |
f0706e82 | 84 | { |
8e8862b7 | 85 | u8 *data, *key = NULL, key_offset; |
f0706e82 | 86 | size_t data_len; |
8e8862b7 HH |
87 | unsigned int hdrlen; |
88 | struct ieee80211_hdr *hdr; | |
f0706e82 JB |
89 | u8 mic[MICHAEL_MIC_LEN]; |
90 | struct sk_buff *skb = rx->skb; | |
91 | int authenticator = 1, wpa_test = 0; | |
92 | ||
c6a1fa12 | 93 | /* No way to verify the MIC if the hardware stripped it */ |
5cf121c3 | 94 | if (rx->status->flag & RX_FLAG_MMIC_STRIPPED) |
9ae54c84 | 95 | return RX_CONTINUE; |
f0706e82 | 96 | |
c34498b9 | 97 | hdr = (struct ieee80211_hdr *)skb->data; |
8f20fc24 | 98 | if (!rx->key || rx->key->conf.alg != ALG_TKIP || |
c34498b9 HH |
99 | !ieee80211_has_protected(hdr->frame_control) || |
100 | !ieee80211_is_data_present(hdr->frame_control)) | |
9ae54c84 | 101 | return RX_CONTINUE; |
f0706e82 | 102 | |
8e8862b7 HH |
103 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
104 | if (skb->len < hdrlen + MICHAEL_MIC_LEN) | |
e4c26add | 105 | return RX_DROP_UNUSABLE; |
f0706e82 | 106 | |
8e8862b7 HH |
107 | data = skb->data + hdrlen; |
108 | data_len = skb->len - hdrlen - MICHAEL_MIC_LEN; | |
f0706e82 JB |
109 | |
110 | #if 0 | |
111 | authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */ | |
112 | #else | |
113 | authenticator = 1; | |
114 | #endif | |
ffd7891d LR |
115 | key_offset = authenticator ? |
116 | NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY : | |
117 | NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY; | |
118 | key = &rx->key->conf.key[key_offset]; | |
8e8862b7 | 119 | michael_mic(key, hdr, data, data_len, mic); |
f0706e82 | 120 | if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 || wpa_test) { |
5cf121c3 | 121 | if (!(rx->flags & IEEE80211_RX_RA_MATCH)) |
e4c26add | 122 | return RX_DROP_UNUSABLE; |
f0706e82 | 123 | |
f698d856 | 124 | mac80211_ev_michael_mic_failure(rx->sdata, rx->key->conf.keyidx, |
eb063c17 | 125 | (void *) skb->data); |
e4c26add | 126 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
127 | } |
128 | ||
f0706e82 JB |
129 | /* remove Michael MIC from payload */ |
130 | skb_trim(skb, skb->len - MICHAEL_MIC_LEN); | |
131 | ||
50741ae0 | 132 | /* update IV in key information to be able to detect replays */ |
b0f76b33 HH |
133 | rx->key->u.tkip.rx[rx->queue].iv32 = rx->tkip_iv32; |
134 | rx->key->u.tkip.rx[rx->queue].iv16 = rx->tkip_iv16; | |
50741ae0 | 135 | |
9ae54c84 | 136 | return RX_CONTINUE; |
f0706e82 JB |
137 | } |
138 | ||
139 | ||
e039fa4a | 140 | static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
f0706e82 JB |
141 | { |
142 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
143 | struct ieee80211_key *key = tx->key; | |
e039fa4a | 144 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
d5184cac HH |
145 | unsigned int hdrlen; |
146 | int len, tail; | |
f0706e82 JB |
147 | u8 *pos; |
148 | ||
e039fa4a JB |
149 | if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && |
150 | !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) { | |
151 | /* hwaccel - with no need for preallocated room for IV/ICV */ | |
152 | info->control.hw_key = &tx->key->conf; | |
23c0752a | 153 | return 0; |
e039fa4a JB |
154 | } |
155 | ||
d5184cac | 156 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 JB |
157 | len = skb->len - hdrlen; |
158 | ||
11a843b7 | 159 | if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) |
23c0752a | 160 | tail = 0; |
11a843b7 | 161 | else |
23c0752a JB |
162 | tail = TKIP_ICV_LEN; |
163 | ||
164 | if (WARN_ON(skb_tailroom(skb) < tail || | |
165 | skb_headroom(skb) < TKIP_IV_LEN)) | |
166 | return -1; | |
f0706e82 JB |
167 | |
168 | pos = skb_push(skb, TKIP_IV_LEN); | |
169 | memmove(pos, pos + TKIP_IV_LEN, hdrlen); | |
170 | pos += hdrlen; | |
171 | ||
172 | /* Increase IV for the frame */ | |
b0f76b33 HH |
173 | key->u.tkip.tx.iv16++; |
174 | if (key->u.tkip.tx.iv16 == 0) | |
175 | key->u.tkip.tx.iv32++; | |
f0706e82 | 176 | |
11a843b7 | 177 | if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) { |
f0706e82 | 178 | /* hwaccel - with preallocated room for IV */ |
c801242c | 179 | ieee80211_tkip_add_iv(pos, key, key->u.tkip.tx.iv16); |
f0706e82 | 180 | |
e039fa4a | 181 | info->control.hw_key = &tx->key->conf; |
f0706e82 JB |
182 | return 0; |
183 | } | |
184 | ||
185 | /* Add room for ICV */ | |
186 | skb_put(skb, TKIP_ICV_LEN); | |
187 | ||
188 | hdr = (struct ieee80211_hdr *) skb->data; | |
189 | ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm, | |
190 | key, pos, len, hdr->addr2); | |
191 | return 0; | |
192 | } | |
193 | ||
194 | ||
9ae54c84 | 195 | ieee80211_tx_result |
5cf121c3 | 196 | ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx) |
f0706e82 | 197 | { |
f0706e82 | 198 | struct sk_buff *skb = tx->skb; |
f0706e82 | 199 | |
5cf121c3 | 200 | ieee80211_tx_set_protected(tx); |
f0706e82 | 201 | |
2de8e0d9 JB |
202 | do { |
203 | if (tkip_encrypt_skb(tx, skb) < 0) | |
204 | return TX_DROP; | |
205 | } while ((skb = skb->next)); | |
f0706e82 | 206 | |
9ae54c84 | 207 | return TX_CONTINUE; |
f0706e82 JB |
208 | } |
209 | ||
210 | ||
9ae54c84 | 211 | ieee80211_rx_result |
5cf121c3 | 212 | ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx) |
f0706e82 JB |
213 | { |
214 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; | |
f0706e82 JB |
215 | int hdrlen, res, hwaccel = 0, wpa_test = 0; |
216 | struct ieee80211_key *key = rx->key; | |
217 | struct sk_buff *skb = rx->skb; | |
218 | ||
d5184cac | 219 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 | 220 | |
c34498b9 | 221 | if (!ieee80211_is_data(hdr->frame_control)) |
9ae54c84 | 222 | return RX_CONTINUE; |
f0706e82 JB |
223 | |
224 | if (!rx->sta || skb->len - hdrlen < 12) | |
e4c26add | 225 | return RX_DROP_UNUSABLE; |
f0706e82 | 226 | |
5cf121c3 JB |
227 | if (rx->status->flag & RX_FLAG_DECRYPTED) { |
228 | if (rx->status->flag & RX_FLAG_IV_STRIPPED) { | |
7848ba7d JB |
229 | /* |
230 | * Hardware took care of all processing, including | |
231 | * replay protection, and stripped the ICV/IV so | |
232 | * we cannot do any checks here. | |
233 | */ | |
9ae54c84 | 234 | return RX_CONTINUE; |
f0706e82 JB |
235 | } |
236 | ||
237 | /* let TKIP code verify IV, but skip decryption */ | |
238 | hwaccel = 1; | |
239 | } | |
240 | ||
241 | res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm, | |
242 | key, skb->data + hdrlen, | |
17741cdc | 243 | skb->len - hdrlen, rx->sta->sta.addr, |
9ae4fda3 | 244 | hdr->addr1, hwaccel, rx->queue, |
5cf121c3 JB |
245 | &rx->tkip_iv32, |
246 | &rx->tkip_iv16); | |
f4ea83dd | 247 | if (res != TKIP_DECRYPT_OK || wpa_test) |
e4c26add | 248 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
249 | |
250 | /* Trim ICV */ | |
251 | skb_trim(skb, skb->len - TKIP_ICV_LEN); | |
252 | ||
253 | /* Remove IV */ | |
254 | memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen); | |
255 | skb_pull(skb, TKIP_IV_LEN); | |
256 | ||
9ae54c84 | 257 | return RX_CONTINUE; |
f0706e82 JB |
258 | } |
259 | ||
260 | ||
feccb466 | 261 | static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch, |
f0706e82 JB |
262 | int encrypted) |
263 | { | |
f14df804 | 264 | __le16 mask_fc; |
fb733336 | 265 | int a4_included, mgmt; |
f14df804 | 266 | u8 qos_tid; |
feccb466 | 267 | u8 *b_0, *aad; |
f14df804 HH |
268 | u16 data_len, len_a; |
269 | unsigned int hdrlen; | |
270 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; | |
f0706e82 | 271 | |
feccb466 HH |
272 | b_0 = scratch + 3 * AES_BLOCK_LEN; |
273 | aad = scratch + 4 * AES_BLOCK_LEN; | |
274 | ||
f14df804 | 275 | /* |
fb733336 | 276 | * Mask FC: zero subtype b4 b5 b6 (if not mgmt) |
f14df804 HH |
277 | * Retry, PwrMgt, MoreData; set Protected |
278 | */ | |
fb733336 | 279 | mgmt = ieee80211_is_mgmt(hdr->frame_control); |
f14df804 | 280 | mask_fc = hdr->frame_control; |
fb733336 | 281 | mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | |
f14df804 | 282 | IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); |
fb733336 JM |
283 | if (!mgmt) |
284 | mask_fc &= ~cpu_to_le16(0x0070); | |
f14df804 HH |
285 | mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); |
286 | ||
287 | hdrlen = ieee80211_hdrlen(hdr->frame_control); | |
288 | len_a = hdrlen - 2; | |
289 | a4_included = ieee80211_has_a4(hdr->frame_control); | |
f0706e82 | 290 | |
f14df804 HH |
291 | if (ieee80211_is_data_qos(hdr->frame_control)) |
292 | qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; | |
293 | else | |
294 | qos_tid = 0; | |
295 | ||
296 | data_len = skb->len - hdrlen - CCMP_HDR_LEN; | |
297 | if (encrypted) | |
298 | data_len -= CCMP_MIC_LEN; | |
299 | ||
300 | /* First block, b_0 */ | |
f0706e82 | 301 | b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */ |
fb733336 JM |
302 | /* Nonce: Nonce Flags | A2 | PN |
303 | * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7) | |
304 | */ | |
305 | b_0[1] = qos_tid | (mgmt << 4); | |
73e1f7c8 | 306 | memcpy(&b_0[2], hdr->addr2, ETH_ALEN); |
f0706e82 JB |
307 | memcpy(&b_0[8], pn, CCMP_PN_LEN); |
308 | /* l(m) */ | |
f14df804 | 309 | put_unaligned_be16(data_len, &b_0[14]); |
f0706e82 JB |
310 | |
311 | /* AAD (extra authenticate-only data) / masked 802.11 header | |
312 | * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ | |
f14df804 HH |
313 | put_unaligned_be16(len_a, &aad[0]); |
314 | put_unaligned(mask_fc, (__le16 *)&aad[2]); | |
73e1f7c8 | 315 | memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); |
f0706e82 JB |
316 | |
317 | /* Mask Seq#, leave Frag# */ | |
318 | aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; | |
319 | aad[23] = 0; | |
f14df804 | 320 | |
f0706e82 | 321 | if (a4_included) { |
73e1f7c8 | 322 | memcpy(&aad[24], hdr->addr4, ETH_ALEN); |
f14df804 | 323 | aad[30] = qos_tid; |
f0706e82 | 324 | aad[31] = 0; |
f14df804 | 325 | } else { |
73e1f7c8 | 326 | memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); |
f14df804 | 327 | aad[24] = qos_tid; |
f0706e82 JB |
328 | } |
329 | } | |
330 | ||
331 | ||
332 | static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) | |
333 | { | |
334 | hdr[0] = pn[5]; | |
335 | hdr[1] = pn[4]; | |
336 | hdr[2] = 0; | |
337 | hdr[3] = 0x20 | (key_id << 6); | |
338 | hdr[4] = pn[3]; | |
339 | hdr[5] = pn[2]; | |
340 | hdr[6] = pn[1]; | |
341 | hdr[7] = pn[0]; | |
342 | } | |
343 | ||
344 | ||
c6a1fa12 | 345 | static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr) |
f0706e82 JB |
346 | { |
347 | pn[0] = hdr[7]; | |
348 | pn[1] = hdr[6]; | |
349 | pn[2] = hdr[5]; | |
350 | pn[3] = hdr[4]; | |
351 | pn[4] = hdr[1]; | |
352 | pn[5] = hdr[0]; | |
f0706e82 JB |
353 | } |
354 | ||
355 | ||
e039fa4a | 356 | static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
f0706e82 JB |
357 | { |
358 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
359 | struct ieee80211_key *key = tx->key; | |
e039fa4a | 360 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
23c0752a | 361 | int hdrlen, len, tail; |
feccb466 | 362 | u8 *pos, *pn; |
f0706e82 | 363 | int i; |
1f7d77ab JM |
364 | bool skip_hw; |
365 | ||
366 | skip_hw = (tx->key->conf.flags & IEEE80211_KEY_FLAG_SW_MGMT) && | |
367 | ieee80211_is_mgmt(hdr->frame_control); | |
f0706e82 | 368 | |
e039fa4a | 369 | if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && |
1f7d77ab JM |
370 | !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) && |
371 | !skip_hw) { | |
c6a1fa12 | 372 | /* hwaccel - with no need for preallocated room for CCMP |
e039fa4a JB |
373 | * header or MIC fields */ |
374 | info->control.hw_key = &tx->key->conf; | |
23c0752a | 375 | return 0; |
e039fa4a JB |
376 | } |
377 | ||
d5184cac | 378 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 JB |
379 | len = skb->len - hdrlen; |
380 | ||
11a843b7 | 381 | if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) |
23c0752a | 382 | tail = 0; |
11a843b7 | 383 | else |
23c0752a JB |
384 | tail = CCMP_MIC_LEN; |
385 | ||
386 | if (WARN_ON(skb_tailroom(skb) < tail || | |
387 | skb_headroom(skb) < CCMP_HDR_LEN)) | |
388 | return -1; | |
f0706e82 JB |
389 | |
390 | pos = skb_push(skb, CCMP_HDR_LEN); | |
391 | memmove(pos, pos + CCMP_HDR_LEN, hdrlen); | |
392 | hdr = (struct ieee80211_hdr *) pos; | |
393 | pos += hdrlen; | |
394 | ||
395 | /* PN = PN + 1 */ | |
396 | pn = key->u.ccmp.tx_pn; | |
397 | ||
398 | for (i = CCMP_PN_LEN - 1; i >= 0; i--) { | |
399 | pn[i]++; | |
400 | if (pn[i]) | |
401 | break; | |
402 | } | |
403 | ||
8f20fc24 | 404 | ccmp_pn2hdr(pos, pn, key->conf.keyidx); |
f0706e82 | 405 | |
1f7d77ab | 406 | if ((key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && !skip_hw) { |
f0706e82 | 407 | /* hwaccel - with preallocated room for CCMP header */ |
e039fa4a | 408 | info->control.hw_key = &tx->key->conf; |
f0706e82 JB |
409 | return 0; |
410 | } | |
411 | ||
412 | pos += CCMP_HDR_LEN; | |
feccb466 HH |
413 | ccmp_special_blocks(skb, pn, key->u.ccmp.tx_crypto_buf, 0); |
414 | ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, key->u.ccmp.tx_crypto_buf, pos, len, | |
f0706e82 JB |
415 | pos, skb_put(skb, CCMP_MIC_LEN)); |
416 | ||
417 | return 0; | |
418 | } | |
419 | ||
420 | ||
9ae54c84 | 421 | ieee80211_tx_result |
5cf121c3 | 422 | ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx) |
f0706e82 | 423 | { |
f0706e82 | 424 | struct sk_buff *skb = tx->skb; |
f0706e82 | 425 | |
5cf121c3 | 426 | ieee80211_tx_set_protected(tx); |
f0706e82 | 427 | |
2de8e0d9 JB |
428 | do { |
429 | if (ccmp_encrypt_skb(tx, skb) < 0) | |
430 | return TX_DROP; | |
431 | } while ((skb = skb->next)); | |
f0706e82 | 432 | |
9ae54c84 | 433 | return TX_CONTINUE; |
f0706e82 JB |
434 | } |
435 | ||
436 | ||
9ae54c84 | 437 | ieee80211_rx_result |
5cf121c3 | 438 | ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx) |
f0706e82 | 439 | { |
c34498b9 | 440 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; |
f0706e82 JB |
441 | int hdrlen; |
442 | struct ieee80211_key *key = rx->key; | |
443 | struct sk_buff *skb = rx->skb; | |
444 | u8 pn[CCMP_PN_LEN]; | |
445 | int data_len; | |
446 | ||
d5184cac | 447 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 | 448 | |
fb733336 JM |
449 | if (!ieee80211_is_data(hdr->frame_control) && |
450 | !ieee80211_is_robust_mgmt_frame(hdr)) | |
9ae54c84 | 451 | return RX_CONTINUE; |
f0706e82 JB |
452 | |
453 | data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN; | |
454 | if (!rx->sta || data_len < 0) | |
e4c26add | 455 | return RX_DROP_UNUSABLE; |
f0706e82 | 456 | |
5cf121c3 JB |
457 | if ((rx->status->flag & RX_FLAG_DECRYPTED) && |
458 | (rx->status->flag & RX_FLAG_IV_STRIPPED)) | |
9ae54c84 | 459 | return RX_CONTINUE; |
f0706e82 | 460 | |
c6a1fa12 | 461 | ccmp_hdr2pn(pn, skb->data + hdrlen); |
f0706e82 | 462 | |
5cf121c3 | 463 | if (memcmp(pn, key->u.ccmp.rx_pn[rx->queue], CCMP_PN_LEN) <= 0) { |
f0706e82 | 464 | key->u.ccmp.replays++; |
e4c26add | 465 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
466 | } |
467 | ||
5cf121c3 | 468 | if (!(rx->status->flag & RX_FLAG_DECRYPTED)) { |
7848ba7d | 469 | /* hardware didn't decrypt/verify MIC */ |
feccb466 | 470 | ccmp_special_blocks(skb, pn, key->u.ccmp.rx_crypto_buf, 1); |
f0706e82 JB |
471 | |
472 | if (ieee80211_aes_ccm_decrypt( | |
feccb466 | 473 | key->u.ccmp.tfm, key->u.ccmp.rx_crypto_buf, |
f0706e82 JB |
474 | skb->data + hdrlen + CCMP_HDR_LEN, data_len, |
475 | skb->data + skb->len - CCMP_MIC_LEN, | |
c6a1fa12 | 476 | skb->data + hdrlen + CCMP_HDR_LEN)) |
e4c26add | 477 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
478 | } |
479 | ||
5cf121c3 | 480 | memcpy(key->u.ccmp.rx_pn[rx->queue], pn, CCMP_PN_LEN); |
f0706e82 JB |
481 | |
482 | /* Remove CCMP header and MIC */ | |
483 | skb_trim(skb, skb->len - CCMP_MIC_LEN); | |
484 | memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen); | |
485 | skb_pull(skb, CCMP_HDR_LEN); | |
486 | ||
9ae54c84 | 487 | return RX_CONTINUE; |
f0706e82 | 488 | } |
765cb46a JM |
489 | |
490 | ||
491 | static void bip_aad(struct sk_buff *skb, u8 *aad) | |
492 | { | |
493 | /* BIP AAD: FC(masked) || A1 || A2 || A3 */ | |
494 | ||
495 | /* FC type/subtype */ | |
496 | aad[0] = skb->data[0]; | |
497 | /* Mask FC Retry, PwrMgt, MoreData flags to zero */ | |
498 | aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6)); | |
499 | /* A1 || A2 || A3 */ | |
500 | memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN); | |
501 | } | |
502 | ||
503 | ||
504 | static inline void bip_ipn_swap(u8 *d, const u8 *s) | |
505 | { | |
506 | *d++ = s[5]; | |
507 | *d++ = s[4]; | |
508 | *d++ = s[3]; | |
509 | *d++ = s[2]; | |
510 | *d++ = s[1]; | |
511 | *d = s[0]; | |
512 | } | |
513 | ||
514 | ||
515 | ieee80211_tx_result | |
516 | ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) | |
517 | { | |
518 | struct sk_buff *skb = tx->skb; | |
519 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); | |
520 | struct ieee80211_key *key = tx->key; | |
521 | struct ieee80211_mmie *mmie; | |
522 | u8 *pn, aad[20]; | |
523 | int i; | |
524 | ||
525 | if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) { | |
526 | /* hwaccel */ | |
527 | info->control.hw_key = &tx->key->conf; | |
528 | return 0; | |
529 | } | |
530 | ||
531 | if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) | |
532 | return TX_DROP; | |
533 | ||
534 | mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie)); | |
535 | mmie->element_id = WLAN_EID_MMIE; | |
536 | mmie->length = sizeof(*mmie) - 2; | |
537 | mmie->key_id = cpu_to_le16(key->conf.keyidx); | |
538 | ||
539 | /* PN = PN + 1 */ | |
540 | pn = key->u.aes_cmac.tx_pn; | |
541 | ||
542 | for (i = sizeof(key->u.aes_cmac.tx_pn) - 1; i >= 0; i--) { | |
543 | pn[i]++; | |
544 | if (pn[i]) | |
545 | break; | |
546 | } | |
547 | bip_ipn_swap(mmie->sequence_number, pn); | |
548 | ||
549 | bip_aad(skb, aad); | |
550 | ||
551 | /* | |
552 | * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) | |
553 | */ | |
554 | ieee80211_aes_cmac(key->u.aes_cmac.tfm, key->u.aes_cmac.tx_crypto_buf, | |
555 | aad, skb->data + 24, skb->len - 24, mmie->mic); | |
556 | ||
557 | return TX_CONTINUE; | |
558 | } | |
559 | ||
560 | ||
561 | ieee80211_rx_result | |
562 | ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) | |
563 | { | |
564 | struct sk_buff *skb = rx->skb; | |
565 | struct ieee80211_key *key = rx->key; | |
566 | struct ieee80211_mmie *mmie; | |
567 | u8 aad[20], mic[8], ipn[6]; | |
568 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
569 | ||
570 | if (!ieee80211_is_mgmt(hdr->frame_control)) | |
571 | return RX_CONTINUE; | |
572 | ||
573 | if ((rx->status->flag & RX_FLAG_DECRYPTED) && | |
574 | (rx->status->flag & RX_FLAG_IV_STRIPPED)) | |
575 | return RX_CONTINUE; | |
576 | ||
577 | if (skb->len < 24 + sizeof(*mmie)) | |
578 | return RX_DROP_UNUSABLE; | |
579 | ||
580 | mmie = (struct ieee80211_mmie *) | |
581 | (skb->data + skb->len - sizeof(*mmie)); | |
582 | if (mmie->element_id != WLAN_EID_MMIE || | |
583 | mmie->length != sizeof(*mmie) - 2) | |
584 | return RX_DROP_UNUSABLE; /* Invalid MMIE */ | |
585 | ||
586 | bip_ipn_swap(ipn, mmie->sequence_number); | |
587 | ||
588 | if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { | |
589 | key->u.aes_cmac.replays++; | |
590 | return RX_DROP_UNUSABLE; | |
591 | } | |
592 | ||
593 | if (!(rx->status->flag & RX_FLAG_DECRYPTED)) { | |
594 | /* hardware didn't decrypt/verify MIC */ | |
595 | bip_aad(skb, aad); | |
596 | ieee80211_aes_cmac(key->u.aes_cmac.tfm, | |
597 | key->u.aes_cmac.rx_crypto_buf, aad, | |
598 | skb->data + 24, skb->len - 24, mic); | |
599 | if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { | |
600 | key->u.aes_cmac.icverrors++; | |
601 | return RX_DROP_UNUSABLE; | |
602 | } | |
603 | } | |
604 | ||
605 | memcpy(key->u.aes_cmac.rx_pn, ipn, 6); | |
606 | ||
607 | /* Remove MMIE */ | |
608 | skb_trim(skb, skb->len - sizeof(*mmie)); | |
609 | ||
610 | return RX_CONTINUE; | |
611 | } |