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 | 87 | unsigned int hdrlen; |
f0706e82 JB |
88 | u8 mic[MICHAEL_MIC_LEN]; |
89 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 JB |
90 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
91 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; | |
f0706e82 JB |
92 | int authenticator = 1, wpa_test = 0; |
93 | ||
c6a1fa12 | 94 | /* No way to verify the MIC if the hardware stripped it */ |
eb9fb5b8 | 95 | if (status->flag & RX_FLAG_MMIC_STRIPPED) |
9ae54c84 | 96 | return RX_CONTINUE; |
f0706e82 | 97 | |
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, |
e6d6e342 JB |
125 | (void *) skb->data, NULL, |
126 | GFP_ATOMIC); | |
e4c26add | 127 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
128 | } |
129 | ||
f0706e82 JB |
130 | /* remove Michael MIC from payload */ |
131 | skb_trim(skb, skb->len - MICHAEL_MIC_LEN); | |
132 | ||
50741ae0 | 133 | /* update IV in key information to be able to detect replays */ |
b0f76b33 HH |
134 | rx->key->u.tkip.rx[rx->queue].iv32 = rx->tkip_iv32; |
135 | rx->key->u.tkip.rx[rx->queue].iv16 = rx->tkip_iv16; | |
50741ae0 | 136 | |
9ae54c84 | 137 | return RX_CONTINUE; |
f0706e82 JB |
138 | } |
139 | ||
140 | ||
e039fa4a | 141 | static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
f0706e82 JB |
142 | { |
143 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
144 | struct ieee80211_key *key = tx->key; | |
e039fa4a | 145 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
d5184cac HH |
146 | unsigned int hdrlen; |
147 | int len, tail; | |
f0706e82 JB |
148 | u8 *pos; |
149 | ||
e039fa4a JB |
150 | if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && |
151 | !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) { | |
152 | /* hwaccel - with no need for preallocated room for IV/ICV */ | |
153 | info->control.hw_key = &tx->key->conf; | |
23c0752a | 154 | return 0; |
e039fa4a JB |
155 | } |
156 | ||
d5184cac | 157 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 JB |
158 | len = skb->len - hdrlen; |
159 | ||
11a843b7 | 160 | if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) |
23c0752a | 161 | tail = 0; |
11a843b7 | 162 | else |
23c0752a JB |
163 | tail = TKIP_ICV_LEN; |
164 | ||
165 | if (WARN_ON(skb_tailroom(skb) < tail || | |
166 | skb_headroom(skb) < TKIP_IV_LEN)) | |
167 | return -1; | |
f0706e82 JB |
168 | |
169 | pos = skb_push(skb, TKIP_IV_LEN); | |
170 | memmove(pos, pos + TKIP_IV_LEN, hdrlen); | |
171 | pos += hdrlen; | |
172 | ||
173 | /* Increase IV for the frame */ | |
b0f76b33 HH |
174 | key->u.tkip.tx.iv16++; |
175 | if (key->u.tkip.tx.iv16 == 0) | |
176 | key->u.tkip.tx.iv32++; | |
f0706e82 | 177 | |
11a843b7 | 178 | if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) { |
f0706e82 | 179 | /* hwaccel - with preallocated room for IV */ |
c801242c | 180 | ieee80211_tkip_add_iv(pos, key, key->u.tkip.tx.iv16); |
f0706e82 | 181 | |
e039fa4a | 182 | info->control.hw_key = &tx->key->conf; |
f0706e82 JB |
183 | return 0; |
184 | } | |
185 | ||
186 | /* Add room for ICV */ | |
187 | skb_put(skb, TKIP_ICV_LEN); | |
188 | ||
189 | hdr = (struct ieee80211_hdr *) skb->data; | |
190 | ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm, | |
191 | key, pos, len, hdr->addr2); | |
192 | return 0; | |
193 | } | |
194 | ||
195 | ||
9ae54c84 | 196 | ieee80211_tx_result |
5cf121c3 | 197 | ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx) |
f0706e82 | 198 | { |
f0706e82 | 199 | struct sk_buff *skb = tx->skb; |
f0706e82 | 200 | |
5cf121c3 | 201 | ieee80211_tx_set_protected(tx); |
f0706e82 | 202 | |
2de8e0d9 JB |
203 | do { |
204 | if (tkip_encrypt_skb(tx, skb) < 0) | |
205 | return TX_DROP; | |
206 | } while ((skb = skb->next)); | |
f0706e82 | 207 | |
9ae54c84 | 208 | return TX_CONTINUE; |
f0706e82 JB |
209 | } |
210 | ||
211 | ||
9ae54c84 | 212 | ieee80211_rx_result |
5cf121c3 | 213 | ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx) |
f0706e82 JB |
214 | { |
215 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; | |
f0706e82 JB |
216 | int hdrlen, res, hwaccel = 0, wpa_test = 0; |
217 | struct ieee80211_key *key = rx->key; | |
218 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 219 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
f0706e82 | 220 | |
d5184cac | 221 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 | 222 | |
c34498b9 | 223 | if (!ieee80211_is_data(hdr->frame_control)) |
9ae54c84 | 224 | return RX_CONTINUE; |
f0706e82 JB |
225 | |
226 | if (!rx->sta || skb->len - hdrlen < 12) | |
e4c26add | 227 | return RX_DROP_UNUSABLE; |
f0706e82 | 228 | |
eb9fb5b8 JB |
229 | if (status->flag & RX_FLAG_DECRYPTED) { |
230 | if (status->flag & RX_FLAG_IV_STRIPPED) { | |
7848ba7d JB |
231 | /* |
232 | * Hardware took care of all processing, including | |
233 | * replay protection, and stripped the ICV/IV so | |
234 | * we cannot do any checks here. | |
235 | */ | |
9ae54c84 | 236 | return RX_CONTINUE; |
f0706e82 JB |
237 | } |
238 | ||
239 | /* let TKIP code verify IV, but skip decryption */ | |
240 | hwaccel = 1; | |
241 | } | |
242 | ||
243 | res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm, | |
244 | key, skb->data + hdrlen, | |
17741cdc | 245 | skb->len - hdrlen, rx->sta->sta.addr, |
9ae4fda3 | 246 | hdr->addr1, hwaccel, rx->queue, |
5cf121c3 JB |
247 | &rx->tkip_iv32, |
248 | &rx->tkip_iv16); | |
f4ea83dd | 249 | if (res != TKIP_DECRYPT_OK || wpa_test) |
e4c26add | 250 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
251 | |
252 | /* Trim ICV */ | |
253 | skb_trim(skb, skb->len - TKIP_ICV_LEN); | |
254 | ||
255 | /* Remove IV */ | |
256 | memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen); | |
257 | skb_pull(skb, TKIP_IV_LEN); | |
258 | ||
9ae54c84 | 259 | return RX_CONTINUE; |
f0706e82 JB |
260 | } |
261 | ||
262 | ||
feccb466 | 263 | static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch, |
f0706e82 JB |
264 | int encrypted) |
265 | { | |
f14df804 | 266 | __le16 mask_fc; |
fb733336 | 267 | int a4_included, mgmt; |
f14df804 | 268 | u8 qos_tid; |
feccb466 | 269 | u8 *b_0, *aad; |
f14df804 HH |
270 | u16 data_len, len_a; |
271 | unsigned int hdrlen; | |
272 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; | |
f0706e82 | 273 | |
feccb466 HH |
274 | b_0 = scratch + 3 * AES_BLOCK_LEN; |
275 | aad = scratch + 4 * AES_BLOCK_LEN; | |
276 | ||
f14df804 | 277 | /* |
fb733336 | 278 | * Mask FC: zero subtype b4 b5 b6 (if not mgmt) |
f14df804 HH |
279 | * Retry, PwrMgt, MoreData; set Protected |
280 | */ | |
fb733336 | 281 | mgmt = ieee80211_is_mgmt(hdr->frame_control); |
f14df804 | 282 | mask_fc = hdr->frame_control; |
fb733336 | 283 | mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | |
f14df804 | 284 | IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); |
fb733336 JM |
285 | if (!mgmt) |
286 | mask_fc &= ~cpu_to_le16(0x0070); | |
f14df804 HH |
287 | mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); |
288 | ||
289 | hdrlen = ieee80211_hdrlen(hdr->frame_control); | |
290 | len_a = hdrlen - 2; | |
291 | a4_included = ieee80211_has_a4(hdr->frame_control); | |
f0706e82 | 292 | |
f14df804 HH |
293 | if (ieee80211_is_data_qos(hdr->frame_control)) |
294 | qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; | |
295 | else | |
296 | qos_tid = 0; | |
297 | ||
298 | data_len = skb->len - hdrlen - CCMP_HDR_LEN; | |
299 | if (encrypted) | |
300 | data_len -= CCMP_MIC_LEN; | |
301 | ||
302 | /* First block, b_0 */ | |
f0706e82 | 303 | b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */ |
fb733336 JM |
304 | /* Nonce: Nonce Flags | A2 | PN |
305 | * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7) | |
306 | */ | |
307 | b_0[1] = qos_tid | (mgmt << 4); | |
73e1f7c8 | 308 | memcpy(&b_0[2], hdr->addr2, ETH_ALEN); |
f0706e82 JB |
309 | memcpy(&b_0[8], pn, CCMP_PN_LEN); |
310 | /* l(m) */ | |
f14df804 | 311 | put_unaligned_be16(data_len, &b_0[14]); |
f0706e82 JB |
312 | |
313 | /* AAD (extra authenticate-only data) / masked 802.11 header | |
314 | * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ | |
f14df804 HH |
315 | put_unaligned_be16(len_a, &aad[0]); |
316 | put_unaligned(mask_fc, (__le16 *)&aad[2]); | |
73e1f7c8 | 317 | memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); |
f0706e82 JB |
318 | |
319 | /* Mask Seq#, leave Frag# */ | |
320 | aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; | |
321 | aad[23] = 0; | |
f14df804 | 322 | |
f0706e82 | 323 | if (a4_included) { |
73e1f7c8 | 324 | memcpy(&aad[24], hdr->addr4, ETH_ALEN); |
f14df804 | 325 | aad[30] = qos_tid; |
f0706e82 | 326 | aad[31] = 0; |
f14df804 | 327 | } else { |
73e1f7c8 | 328 | memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); |
f14df804 | 329 | aad[24] = qos_tid; |
f0706e82 JB |
330 | } |
331 | } | |
332 | ||
333 | ||
334 | static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) | |
335 | { | |
336 | hdr[0] = pn[5]; | |
337 | hdr[1] = pn[4]; | |
338 | hdr[2] = 0; | |
339 | hdr[3] = 0x20 | (key_id << 6); | |
340 | hdr[4] = pn[3]; | |
341 | hdr[5] = pn[2]; | |
342 | hdr[6] = pn[1]; | |
343 | hdr[7] = pn[0]; | |
344 | } | |
345 | ||
346 | ||
c6a1fa12 | 347 | static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr) |
f0706e82 JB |
348 | { |
349 | pn[0] = hdr[7]; | |
350 | pn[1] = hdr[6]; | |
351 | pn[2] = hdr[5]; | |
352 | pn[3] = hdr[4]; | |
353 | pn[4] = hdr[1]; | |
354 | pn[5] = hdr[0]; | |
f0706e82 JB |
355 | } |
356 | ||
357 | ||
e039fa4a | 358 | static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
f0706e82 JB |
359 | { |
360 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
361 | struct ieee80211_key *key = tx->key; | |
e039fa4a | 362 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
23c0752a | 363 | int hdrlen, len, tail; |
feccb466 | 364 | u8 *pos, *pn; |
f0706e82 | 365 | int i; |
1f7d77ab JM |
366 | bool skip_hw; |
367 | ||
368 | skip_hw = (tx->key->conf.flags & IEEE80211_KEY_FLAG_SW_MGMT) && | |
369 | ieee80211_is_mgmt(hdr->frame_control); | |
f0706e82 | 370 | |
e039fa4a | 371 | if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && |
1f7d77ab JM |
372 | !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) && |
373 | !skip_hw) { | |
c6a1fa12 | 374 | /* hwaccel - with no need for preallocated room for CCMP |
e039fa4a JB |
375 | * header or MIC fields */ |
376 | info->control.hw_key = &tx->key->conf; | |
23c0752a | 377 | return 0; |
e039fa4a JB |
378 | } |
379 | ||
d5184cac | 380 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 JB |
381 | len = skb->len - hdrlen; |
382 | ||
11a843b7 | 383 | if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) |
23c0752a | 384 | tail = 0; |
11a843b7 | 385 | else |
23c0752a JB |
386 | tail = CCMP_MIC_LEN; |
387 | ||
388 | if (WARN_ON(skb_tailroom(skb) < tail || | |
389 | skb_headroom(skb) < CCMP_HDR_LEN)) | |
390 | return -1; | |
f0706e82 JB |
391 | |
392 | pos = skb_push(skb, CCMP_HDR_LEN); | |
393 | memmove(pos, pos + CCMP_HDR_LEN, hdrlen); | |
394 | hdr = (struct ieee80211_hdr *) pos; | |
395 | pos += hdrlen; | |
396 | ||
397 | /* PN = PN + 1 */ | |
398 | pn = key->u.ccmp.tx_pn; | |
399 | ||
400 | for (i = CCMP_PN_LEN - 1; i >= 0; i--) { | |
401 | pn[i]++; | |
402 | if (pn[i]) | |
403 | break; | |
404 | } | |
405 | ||
8f20fc24 | 406 | ccmp_pn2hdr(pos, pn, key->conf.keyidx); |
f0706e82 | 407 | |
1f7d77ab | 408 | if ((key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && !skip_hw) { |
f0706e82 | 409 | /* hwaccel - with preallocated room for CCMP header */ |
e039fa4a | 410 | info->control.hw_key = &tx->key->conf; |
f0706e82 JB |
411 | return 0; |
412 | } | |
413 | ||
414 | pos += CCMP_HDR_LEN; | |
feccb466 HH |
415 | ccmp_special_blocks(skb, pn, key->u.ccmp.tx_crypto_buf, 0); |
416 | ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, key->u.ccmp.tx_crypto_buf, pos, len, | |
f0706e82 JB |
417 | pos, skb_put(skb, CCMP_MIC_LEN)); |
418 | ||
419 | return 0; | |
420 | } | |
421 | ||
422 | ||
9ae54c84 | 423 | ieee80211_tx_result |
5cf121c3 | 424 | ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx) |
f0706e82 | 425 | { |
f0706e82 | 426 | struct sk_buff *skb = tx->skb; |
f0706e82 | 427 | |
5cf121c3 | 428 | ieee80211_tx_set_protected(tx); |
f0706e82 | 429 | |
2de8e0d9 JB |
430 | do { |
431 | if (ccmp_encrypt_skb(tx, skb) < 0) | |
432 | return TX_DROP; | |
433 | } while ((skb = skb->next)); | |
f0706e82 | 434 | |
9ae54c84 | 435 | return TX_CONTINUE; |
f0706e82 JB |
436 | } |
437 | ||
438 | ||
9ae54c84 | 439 | ieee80211_rx_result |
5cf121c3 | 440 | ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx) |
f0706e82 | 441 | { |
c34498b9 | 442 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; |
f0706e82 JB |
443 | int hdrlen; |
444 | struct ieee80211_key *key = rx->key; | |
445 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 446 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
f0706e82 JB |
447 | u8 pn[CCMP_PN_LEN]; |
448 | int data_len; | |
449 | ||
d5184cac | 450 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 | 451 | |
fb733336 JM |
452 | if (!ieee80211_is_data(hdr->frame_control) && |
453 | !ieee80211_is_robust_mgmt_frame(hdr)) | |
9ae54c84 | 454 | return RX_CONTINUE; |
f0706e82 JB |
455 | |
456 | data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN; | |
457 | if (!rx->sta || data_len < 0) | |
e4c26add | 458 | return RX_DROP_UNUSABLE; |
f0706e82 | 459 | |
eb9fb5b8 JB |
460 | if ((status->flag & RX_FLAG_DECRYPTED) && |
461 | (status->flag & RX_FLAG_IV_STRIPPED)) | |
9ae54c84 | 462 | return RX_CONTINUE; |
f0706e82 | 463 | |
c6a1fa12 | 464 | ccmp_hdr2pn(pn, skb->data + hdrlen); |
f0706e82 | 465 | |
5cf121c3 | 466 | if (memcmp(pn, key->u.ccmp.rx_pn[rx->queue], CCMP_PN_LEN) <= 0) { |
f0706e82 | 467 | key->u.ccmp.replays++; |
e4c26add | 468 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
469 | } |
470 | ||
eb9fb5b8 | 471 | if (!(status->flag & RX_FLAG_DECRYPTED)) { |
7848ba7d | 472 | /* hardware didn't decrypt/verify MIC */ |
feccb466 | 473 | ccmp_special_blocks(skb, pn, key->u.ccmp.rx_crypto_buf, 1); |
f0706e82 JB |
474 | |
475 | if (ieee80211_aes_ccm_decrypt( | |
feccb466 | 476 | key->u.ccmp.tfm, key->u.ccmp.rx_crypto_buf, |
f0706e82 JB |
477 | skb->data + hdrlen + CCMP_HDR_LEN, data_len, |
478 | skb->data + skb->len - CCMP_MIC_LEN, | |
c6a1fa12 | 479 | skb->data + hdrlen + CCMP_HDR_LEN)) |
e4c26add | 480 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
481 | } |
482 | ||
5cf121c3 | 483 | memcpy(key->u.ccmp.rx_pn[rx->queue], pn, CCMP_PN_LEN); |
f0706e82 JB |
484 | |
485 | /* Remove CCMP header and MIC */ | |
486 | skb_trim(skb, skb->len - CCMP_MIC_LEN); | |
487 | memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen); | |
488 | skb_pull(skb, CCMP_HDR_LEN); | |
489 | ||
9ae54c84 | 490 | return RX_CONTINUE; |
f0706e82 | 491 | } |
765cb46a JM |
492 | |
493 | ||
494 | static void bip_aad(struct sk_buff *skb, u8 *aad) | |
495 | { | |
496 | /* BIP AAD: FC(masked) || A1 || A2 || A3 */ | |
497 | ||
498 | /* FC type/subtype */ | |
499 | aad[0] = skb->data[0]; | |
500 | /* Mask FC Retry, PwrMgt, MoreData flags to zero */ | |
501 | aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6)); | |
502 | /* A1 || A2 || A3 */ | |
503 | memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN); | |
504 | } | |
505 | ||
506 | ||
507 | static inline void bip_ipn_swap(u8 *d, const u8 *s) | |
508 | { | |
509 | *d++ = s[5]; | |
510 | *d++ = s[4]; | |
511 | *d++ = s[3]; | |
512 | *d++ = s[2]; | |
513 | *d++ = s[1]; | |
514 | *d = s[0]; | |
515 | } | |
516 | ||
517 | ||
518 | ieee80211_tx_result | |
519 | ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) | |
520 | { | |
521 | struct sk_buff *skb = tx->skb; | |
522 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); | |
523 | struct ieee80211_key *key = tx->key; | |
524 | struct ieee80211_mmie *mmie; | |
525 | u8 *pn, aad[20]; | |
526 | int i; | |
527 | ||
528 | if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) { | |
529 | /* hwaccel */ | |
530 | info->control.hw_key = &tx->key->conf; | |
531 | return 0; | |
532 | } | |
533 | ||
534 | if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) | |
535 | return TX_DROP; | |
536 | ||
537 | mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie)); | |
538 | mmie->element_id = WLAN_EID_MMIE; | |
539 | mmie->length = sizeof(*mmie) - 2; | |
540 | mmie->key_id = cpu_to_le16(key->conf.keyidx); | |
541 | ||
542 | /* PN = PN + 1 */ | |
543 | pn = key->u.aes_cmac.tx_pn; | |
544 | ||
545 | for (i = sizeof(key->u.aes_cmac.tx_pn) - 1; i >= 0; i--) { | |
546 | pn[i]++; | |
547 | if (pn[i]) | |
548 | break; | |
549 | } | |
550 | bip_ipn_swap(mmie->sequence_number, pn); | |
551 | ||
552 | bip_aad(skb, aad); | |
553 | ||
554 | /* | |
555 | * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) | |
556 | */ | |
557 | ieee80211_aes_cmac(key->u.aes_cmac.tfm, key->u.aes_cmac.tx_crypto_buf, | |
558 | aad, skb->data + 24, skb->len - 24, mmie->mic); | |
559 | ||
560 | return TX_CONTINUE; | |
561 | } | |
562 | ||
563 | ||
564 | ieee80211_rx_result | |
565 | ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) | |
566 | { | |
567 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 568 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
765cb46a JM |
569 | struct ieee80211_key *key = rx->key; |
570 | struct ieee80211_mmie *mmie; | |
571 | u8 aad[20], mic[8], ipn[6]; | |
572 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
573 | ||
574 | if (!ieee80211_is_mgmt(hdr->frame_control)) | |
575 | return RX_CONTINUE; | |
576 | ||
eb9fb5b8 JB |
577 | if ((status->flag & RX_FLAG_DECRYPTED) && |
578 | (status->flag & RX_FLAG_IV_STRIPPED)) | |
765cb46a JM |
579 | return RX_CONTINUE; |
580 | ||
581 | if (skb->len < 24 + sizeof(*mmie)) | |
582 | return RX_DROP_UNUSABLE; | |
583 | ||
584 | mmie = (struct ieee80211_mmie *) | |
585 | (skb->data + skb->len - sizeof(*mmie)); | |
586 | if (mmie->element_id != WLAN_EID_MMIE || | |
587 | mmie->length != sizeof(*mmie) - 2) | |
588 | return RX_DROP_UNUSABLE; /* Invalid MMIE */ | |
589 | ||
590 | bip_ipn_swap(ipn, mmie->sequence_number); | |
591 | ||
592 | if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { | |
593 | key->u.aes_cmac.replays++; | |
594 | return RX_DROP_UNUSABLE; | |
595 | } | |
596 | ||
eb9fb5b8 | 597 | if (!(status->flag & RX_FLAG_DECRYPTED)) { |
765cb46a JM |
598 | /* hardware didn't decrypt/verify MIC */ |
599 | bip_aad(skb, aad); | |
600 | ieee80211_aes_cmac(key->u.aes_cmac.tfm, | |
601 | key->u.aes_cmac.rx_crypto_buf, aad, | |
602 | skb->data + 24, skb->len - 24, mic); | |
603 | if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { | |
604 | key->u.aes_cmac.icverrors++; | |
605 | return RX_DROP_UNUSABLE; | |
606 | } | |
607 | } | |
608 | ||
609 | memcpy(key->u.aes_cmac.rx_pn, ipn, 6); | |
610 | ||
611 | /* Remove MMIE */ | |
612 | skb_trim(skb, skb->len - sizeof(*mmie)); | |
613 | ||
614 | return RX_CONTINUE; | |
615 | } |