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> | |
f0706e82 JB |
12 | #include <linux/skbuff.h> |
13 | #include <linux/compiler.h> | |
f14df804 | 14 | #include <linux/ieee80211.h> |
5a0e3ad6 | 15 | #include <linux/gfp.h> |
f14df804 | 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 | { |
747d753d | 29 | u8 *data, *key, *mic; |
f0706e82 | 30 | size_t data_len; |
8e8862b7 HH |
31 | unsigned int hdrlen; |
32 | struct ieee80211_hdr *hdr; | |
f0706e82 | 33 | struct sk_buff *skb = tx->skb; |
813d7669 | 34 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
23c0752a | 35 | int tail; |
f0706e82 | 36 | |
c34498b9 | 37 | hdr = (struct ieee80211_hdr *)skb->data; |
97359d12 JB |
38 | if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || |
39 | skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control)) | |
9ae54c84 | 40 | return TX_CONTINUE; |
f0706e82 | 41 | |
8e8862b7 HH |
42 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
43 | if (skb->len < hdrlen) | |
9ae54c84 | 44 | return TX_DROP; |
f0706e82 | 45 | |
8e8862b7 HH |
46 | data = skb->data + hdrlen; |
47 | data_len = skb->len - hdrlen; | |
48 | ||
681d1190 JM |
49 | if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) { |
50 | /* Need to use software crypto for the test */ | |
51 | info->control.hw_key = NULL; | |
52 | } | |
53 | ||
813d7669 | 54 | if (info->control.hw_key && |
5cf121c3 | 55 | !(tx->flags & IEEE80211_TX_FRAGMENTED) && |
813d7669 JB |
56 | !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) { |
57 | /* hwaccel - with no need for SW-generated MMIC */ | |
9ae54c84 | 58 | return TX_CONTINUE; |
f0706e82 JB |
59 | } |
60 | ||
23c0752a | 61 | tail = MICHAEL_MIC_LEN; |
813d7669 | 62 | if (!info->control.hw_key) |
23c0752a JB |
63 | tail += TKIP_ICV_LEN; |
64 | ||
65 | if (WARN_ON(skb_tailroom(skb) < tail || | |
66 | skb_headroom(skb) < TKIP_IV_LEN)) | |
67 | return TX_DROP; | |
f0706e82 | 68 | |
747d753d | 69 | key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY]; |
f0706e82 | 70 | mic = skb_put(skb, MICHAEL_MIC_LEN); |
8e8862b7 | 71 | michael_mic(key, hdr, data, data_len, mic); |
681d1190 JM |
72 | if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) |
73 | mic[0]++; | |
f0706e82 | 74 | |
9ae54c84 | 75 | return TX_CONTINUE; |
f0706e82 JB |
76 | } |
77 | ||
78 | ||
9ae54c84 | 79 | ieee80211_rx_result |
5cf121c3 | 80 | ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) |
f0706e82 | 81 | { |
747d753d | 82 | u8 *data, *key = NULL; |
f0706e82 | 83 | size_t data_len; |
8e8862b7 | 84 | unsigned int hdrlen; |
f0706e82 JB |
85 | u8 mic[MICHAEL_MIC_LEN]; |
86 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 JB |
87 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
88 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; | |
f0706e82 | 89 | |
c6a1fa12 | 90 | /* No way to verify the MIC if the hardware stripped it */ |
eb9fb5b8 | 91 | if (status->flag & RX_FLAG_MMIC_STRIPPED) |
9ae54c84 | 92 | return RX_CONTINUE; |
f0706e82 | 93 | |
97359d12 | 94 | if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || |
c34498b9 HH |
95 | !ieee80211_has_protected(hdr->frame_control) || |
96 | !ieee80211_is_data_present(hdr->frame_control)) | |
9ae54c84 | 97 | return RX_CONTINUE; |
f0706e82 | 98 | |
8e8862b7 HH |
99 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
100 | if (skb->len < hdrlen + MICHAEL_MIC_LEN) | |
e4c26add | 101 | return RX_DROP_UNUSABLE; |
f0706e82 | 102 | |
8e8862b7 HH |
103 | data = skb->data + hdrlen; |
104 | data_len = skb->len - hdrlen - MICHAEL_MIC_LEN; | |
f0706e82 | 105 | |
747d753d | 106 | key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY]; |
8e8862b7 | 107 | michael_mic(key, hdr, data, data_len, mic); |
747d753d | 108 | if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0) { |
554891e6 | 109 | if (!(status->rx_flags & IEEE80211_RX_RA_MATCH)) |
e4c26add | 110 | return RX_DROP_UNUSABLE; |
f0706e82 | 111 | |
f698d856 | 112 | mac80211_ev_michael_mic_failure(rx->sdata, rx->key->conf.keyidx, |
e6d6e342 JB |
113 | (void *) skb->data, NULL, |
114 | GFP_ATOMIC); | |
e4c26add | 115 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
116 | } |
117 | ||
f0706e82 JB |
118 | /* remove Michael MIC from payload */ |
119 | skb_trim(skb, skb->len - MICHAEL_MIC_LEN); | |
120 | ||
50741ae0 | 121 | /* update IV in key information to be able to detect replays */ |
b0f76b33 HH |
122 | rx->key->u.tkip.rx[rx->queue].iv32 = rx->tkip_iv32; |
123 | rx->key->u.tkip.rx[rx->queue].iv16 = rx->tkip_iv16; | |
50741ae0 | 124 | |
9ae54c84 | 125 | return RX_CONTINUE; |
f0706e82 JB |
126 | } |
127 | ||
128 | ||
e039fa4a | 129 | static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
f0706e82 JB |
130 | { |
131 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
132 | struct ieee80211_key *key = tx->key; | |
e039fa4a | 133 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
d5184cac HH |
134 | unsigned int hdrlen; |
135 | int len, tail; | |
f0706e82 JB |
136 | u8 *pos; |
137 | ||
813d7669 JB |
138 | if (info->control.hw_key && |
139 | !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) { | |
140 | /* hwaccel - with no need for software-generated IV */ | |
23c0752a | 141 | return 0; |
e039fa4a JB |
142 | } |
143 | ||
d5184cac | 144 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 JB |
145 | len = skb->len - hdrlen; |
146 | ||
813d7669 | 147 | if (info->control.hw_key) |
23c0752a | 148 | tail = 0; |
11a843b7 | 149 | else |
23c0752a JB |
150 | tail = TKIP_ICV_LEN; |
151 | ||
152 | if (WARN_ON(skb_tailroom(skb) < tail || | |
153 | skb_headroom(skb) < TKIP_IV_LEN)) | |
154 | return -1; | |
f0706e82 JB |
155 | |
156 | pos = skb_push(skb, TKIP_IV_LEN); | |
157 | memmove(pos, pos + TKIP_IV_LEN, hdrlen); | |
158 | pos += hdrlen; | |
159 | ||
160 | /* Increase IV for the frame */ | |
b0f76b33 HH |
161 | key->u.tkip.tx.iv16++; |
162 | if (key->u.tkip.tx.iv16 == 0) | |
163 | key->u.tkip.tx.iv32++; | |
f0706e82 | 164 | |
813d7669 | 165 | pos = ieee80211_tkip_add_iv(pos, key, key->u.tkip.tx.iv16); |
f0706e82 | 166 | |
813d7669 JB |
167 | /* hwaccel - with software IV */ |
168 | if (info->control.hw_key) | |
f0706e82 | 169 | return 0; |
f0706e82 JB |
170 | |
171 | /* Add room for ICV */ | |
172 | skb_put(skb, TKIP_ICV_LEN); | |
173 | ||
174 | hdr = (struct ieee80211_hdr *) skb->data; | |
3473187d JL |
175 | return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm, |
176 | key, pos, len, hdr->addr2); | |
f0706e82 JB |
177 | } |
178 | ||
179 | ||
9ae54c84 | 180 | ieee80211_tx_result |
5cf121c3 | 181 | ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx) |
f0706e82 | 182 | { |
f0706e82 | 183 | struct sk_buff *skb = tx->skb; |
f0706e82 | 184 | |
5cf121c3 | 185 | ieee80211_tx_set_protected(tx); |
f0706e82 | 186 | |
2de8e0d9 JB |
187 | do { |
188 | if (tkip_encrypt_skb(tx, skb) < 0) | |
189 | return TX_DROP; | |
190 | } while ((skb = skb->next)); | |
f0706e82 | 191 | |
9ae54c84 | 192 | return TX_CONTINUE; |
f0706e82 JB |
193 | } |
194 | ||
195 | ||
9ae54c84 | 196 | ieee80211_rx_result |
5cf121c3 | 197 | ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx) |
f0706e82 JB |
198 | { |
199 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; | |
747d753d | 200 | int hdrlen, res, hwaccel = 0; |
f0706e82 JB |
201 | struct ieee80211_key *key = rx->key; |
202 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 203 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
f0706e82 | 204 | |
d5184cac | 205 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 | 206 | |
c34498b9 | 207 | if (!ieee80211_is_data(hdr->frame_control)) |
9ae54c84 | 208 | return RX_CONTINUE; |
f0706e82 JB |
209 | |
210 | if (!rx->sta || skb->len - hdrlen < 12) | |
e4c26add | 211 | return RX_DROP_UNUSABLE; |
f0706e82 | 212 | |
dc1580dd JB |
213 | /* |
214 | * Let TKIP code verify IV, but skip decryption. | |
215 | * In the case where hardware checks the IV as well, | |
216 | * we don't even get here, see ieee80211_rx_h_decrypt() | |
217 | */ | |
218 | if (status->flag & RX_FLAG_DECRYPTED) | |
f0706e82 | 219 | hwaccel = 1; |
f0706e82 JB |
220 | |
221 | res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm, | |
222 | key, skb->data + hdrlen, | |
17741cdc | 223 | skb->len - hdrlen, rx->sta->sta.addr, |
9ae4fda3 | 224 | hdr->addr1, hwaccel, rx->queue, |
5cf121c3 JB |
225 | &rx->tkip_iv32, |
226 | &rx->tkip_iv16); | |
747d753d | 227 | if (res != TKIP_DECRYPT_OK) |
e4c26add | 228 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
229 | |
230 | /* Trim ICV */ | |
231 | skb_trim(skb, skb->len - TKIP_ICV_LEN); | |
232 | ||
233 | /* Remove IV */ | |
234 | memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen); | |
235 | skb_pull(skb, TKIP_IV_LEN); | |
236 | ||
9ae54c84 | 237 | return RX_CONTINUE; |
f0706e82 JB |
238 | } |
239 | ||
240 | ||
feccb466 | 241 | static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch, |
f0706e82 JB |
242 | int encrypted) |
243 | { | |
f14df804 | 244 | __le16 mask_fc; |
fb733336 | 245 | int a4_included, mgmt; |
f14df804 | 246 | u8 qos_tid; |
feccb466 | 247 | u8 *b_0, *aad; |
f14df804 HH |
248 | u16 data_len, len_a; |
249 | unsigned int hdrlen; | |
250 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; | |
f0706e82 | 251 | |
feccb466 HH |
252 | b_0 = scratch + 3 * AES_BLOCK_LEN; |
253 | aad = scratch + 4 * AES_BLOCK_LEN; | |
254 | ||
f14df804 | 255 | /* |
fb733336 | 256 | * Mask FC: zero subtype b4 b5 b6 (if not mgmt) |
f14df804 HH |
257 | * Retry, PwrMgt, MoreData; set Protected |
258 | */ | |
fb733336 | 259 | mgmt = ieee80211_is_mgmt(hdr->frame_control); |
f14df804 | 260 | mask_fc = hdr->frame_control; |
fb733336 | 261 | mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | |
f14df804 | 262 | IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); |
fb733336 JM |
263 | if (!mgmt) |
264 | mask_fc &= ~cpu_to_le16(0x0070); | |
f14df804 HH |
265 | mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); |
266 | ||
267 | hdrlen = ieee80211_hdrlen(hdr->frame_control); | |
268 | len_a = hdrlen - 2; | |
269 | a4_included = ieee80211_has_a4(hdr->frame_control); | |
f0706e82 | 270 | |
f14df804 HH |
271 | if (ieee80211_is_data_qos(hdr->frame_control)) |
272 | qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; | |
273 | else | |
274 | qos_tid = 0; | |
275 | ||
276 | data_len = skb->len - hdrlen - CCMP_HDR_LEN; | |
277 | if (encrypted) | |
278 | data_len -= CCMP_MIC_LEN; | |
279 | ||
280 | /* First block, b_0 */ | |
f0706e82 | 281 | b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */ |
fb733336 JM |
282 | /* Nonce: Nonce Flags | A2 | PN |
283 | * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7) | |
284 | */ | |
285 | b_0[1] = qos_tid | (mgmt << 4); | |
73e1f7c8 | 286 | memcpy(&b_0[2], hdr->addr2, ETH_ALEN); |
f0706e82 JB |
287 | memcpy(&b_0[8], pn, CCMP_PN_LEN); |
288 | /* l(m) */ | |
f14df804 | 289 | put_unaligned_be16(data_len, &b_0[14]); |
f0706e82 JB |
290 | |
291 | /* AAD (extra authenticate-only data) / masked 802.11 header | |
292 | * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ | |
f14df804 HH |
293 | put_unaligned_be16(len_a, &aad[0]); |
294 | put_unaligned(mask_fc, (__le16 *)&aad[2]); | |
73e1f7c8 | 295 | memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); |
f0706e82 JB |
296 | |
297 | /* Mask Seq#, leave Frag# */ | |
298 | aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; | |
299 | aad[23] = 0; | |
f14df804 | 300 | |
f0706e82 | 301 | if (a4_included) { |
73e1f7c8 | 302 | memcpy(&aad[24], hdr->addr4, ETH_ALEN); |
f14df804 | 303 | aad[30] = qos_tid; |
f0706e82 | 304 | aad[31] = 0; |
f14df804 | 305 | } else { |
73e1f7c8 | 306 | memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); |
f14df804 | 307 | aad[24] = qos_tid; |
f0706e82 JB |
308 | } |
309 | } | |
310 | ||
311 | ||
312 | static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) | |
313 | { | |
314 | hdr[0] = pn[5]; | |
315 | hdr[1] = pn[4]; | |
316 | hdr[2] = 0; | |
317 | hdr[3] = 0x20 | (key_id << 6); | |
318 | hdr[4] = pn[3]; | |
319 | hdr[5] = pn[2]; | |
320 | hdr[6] = pn[1]; | |
321 | hdr[7] = pn[0]; | |
322 | } | |
323 | ||
324 | ||
c6a1fa12 | 325 | static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr) |
f0706e82 JB |
326 | { |
327 | pn[0] = hdr[7]; | |
328 | pn[1] = hdr[6]; | |
329 | pn[2] = hdr[5]; | |
330 | pn[3] = hdr[4]; | |
331 | pn[4] = hdr[1]; | |
332 | pn[5] = hdr[0]; | |
f0706e82 JB |
333 | } |
334 | ||
335 | ||
e039fa4a | 336 | static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
f0706e82 JB |
337 | { |
338 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
339 | struct ieee80211_key *key = tx->key; | |
e039fa4a | 340 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
23c0752a | 341 | int hdrlen, len, tail; |
feccb466 | 342 | u8 *pos, *pn; |
f0706e82 JB |
343 | int i; |
344 | ||
813d7669 JB |
345 | if (info->control.hw_key && |
346 | !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) { | |
347 | /* | |
348 | * hwaccel has no need for preallocated room for CCMP | |
349 | * header or MIC fields | |
350 | */ | |
23c0752a | 351 | return 0; |
e039fa4a JB |
352 | } |
353 | ||
d5184cac | 354 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 JB |
355 | len = skb->len - hdrlen; |
356 | ||
813d7669 | 357 | if (info->control.hw_key) |
23c0752a | 358 | tail = 0; |
11a843b7 | 359 | else |
23c0752a JB |
360 | tail = CCMP_MIC_LEN; |
361 | ||
362 | if (WARN_ON(skb_tailroom(skb) < tail || | |
363 | skb_headroom(skb) < CCMP_HDR_LEN)) | |
364 | return -1; | |
f0706e82 JB |
365 | |
366 | pos = skb_push(skb, CCMP_HDR_LEN); | |
367 | memmove(pos, pos + CCMP_HDR_LEN, hdrlen); | |
368 | hdr = (struct ieee80211_hdr *) pos; | |
369 | pos += hdrlen; | |
370 | ||
371 | /* PN = PN + 1 */ | |
372 | pn = key->u.ccmp.tx_pn; | |
373 | ||
374 | for (i = CCMP_PN_LEN - 1; i >= 0; i--) { | |
375 | pn[i]++; | |
376 | if (pn[i]) | |
377 | break; | |
378 | } | |
379 | ||
8f20fc24 | 380 | ccmp_pn2hdr(pos, pn, key->conf.keyidx); |
f0706e82 | 381 | |
813d7669 JB |
382 | /* hwaccel - with software CCMP header */ |
383 | if (info->control.hw_key) | |
f0706e82 | 384 | return 0; |
f0706e82 JB |
385 | |
386 | pos += CCMP_HDR_LEN; | |
feccb466 HH |
387 | ccmp_special_blocks(skb, pn, key->u.ccmp.tx_crypto_buf, 0); |
388 | ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, key->u.ccmp.tx_crypto_buf, pos, len, | |
f0706e82 JB |
389 | pos, skb_put(skb, CCMP_MIC_LEN)); |
390 | ||
391 | return 0; | |
392 | } | |
393 | ||
394 | ||
9ae54c84 | 395 | ieee80211_tx_result |
5cf121c3 | 396 | ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx) |
f0706e82 | 397 | { |
f0706e82 | 398 | struct sk_buff *skb = tx->skb; |
f0706e82 | 399 | |
5cf121c3 | 400 | ieee80211_tx_set_protected(tx); |
f0706e82 | 401 | |
2de8e0d9 JB |
402 | do { |
403 | if (ccmp_encrypt_skb(tx, skb) < 0) | |
404 | return TX_DROP; | |
405 | } while ((skb = skb->next)); | |
f0706e82 | 406 | |
9ae54c84 | 407 | return TX_CONTINUE; |
f0706e82 JB |
408 | } |
409 | ||
410 | ||
9ae54c84 | 411 | ieee80211_rx_result |
5cf121c3 | 412 | ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx) |
f0706e82 | 413 | { |
c34498b9 | 414 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; |
f0706e82 JB |
415 | int hdrlen; |
416 | struct ieee80211_key *key = rx->key; | |
417 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 418 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
f0706e82 JB |
419 | u8 pn[CCMP_PN_LEN]; |
420 | int data_len; | |
9190252c | 421 | int queue; |
f0706e82 | 422 | |
d5184cac | 423 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 | 424 | |
fb733336 JM |
425 | if (!ieee80211_is_data(hdr->frame_control) && |
426 | !ieee80211_is_robust_mgmt_frame(hdr)) | |
9ae54c84 | 427 | return RX_CONTINUE; |
f0706e82 JB |
428 | |
429 | data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN; | |
430 | if (!rx->sta || data_len < 0) | |
e4c26add | 431 | return RX_DROP_UNUSABLE; |
f0706e82 | 432 | |
c6a1fa12 | 433 | ccmp_hdr2pn(pn, skb->data + hdrlen); |
f0706e82 | 434 | |
9190252c JM |
435 | queue = ieee80211_is_mgmt(hdr->frame_control) ? |
436 | NUM_RX_DATA_QUEUES : rx->queue; | |
437 | ||
438 | if (memcmp(pn, key->u.ccmp.rx_pn[queue], CCMP_PN_LEN) <= 0) { | |
f0706e82 | 439 | key->u.ccmp.replays++; |
e4c26add | 440 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
441 | } |
442 | ||
eb9fb5b8 | 443 | if (!(status->flag & RX_FLAG_DECRYPTED)) { |
7848ba7d | 444 | /* hardware didn't decrypt/verify MIC */ |
feccb466 | 445 | ccmp_special_blocks(skb, pn, key->u.ccmp.rx_crypto_buf, 1); |
f0706e82 JB |
446 | |
447 | if (ieee80211_aes_ccm_decrypt( | |
feccb466 | 448 | key->u.ccmp.tfm, key->u.ccmp.rx_crypto_buf, |
f0706e82 JB |
449 | skb->data + hdrlen + CCMP_HDR_LEN, data_len, |
450 | skb->data + skb->len - CCMP_MIC_LEN, | |
c6a1fa12 | 451 | skb->data + hdrlen + CCMP_HDR_LEN)) |
e4c26add | 452 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
453 | } |
454 | ||
9190252c | 455 | memcpy(key->u.ccmp.rx_pn[queue], pn, CCMP_PN_LEN); |
f0706e82 JB |
456 | |
457 | /* Remove CCMP header and MIC */ | |
458 | skb_trim(skb, skb->len - CCMP_MIC_LEN); | |
459 | memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen); | |
460 | skb_pull(skb, CCMP_HDR_LEN); | |
461 | ||
9ae54c84 | 462 | return RX_CONTINUE; |
f0706e82 | 463 | } |
765cb46a JM |
464 | |
465 | ||
466 | static void bip_aad(struct sk_buff *skb, u8 *aad) | |
467 | { | |
468 | /* BIP AAD: FC(masked) || A1 || A2 || A3 */ | |
469 | ||
470 | /* FC type/subtype */ | |
471 | aad[0] = skb->data[0]; | |
472 | /* Mask FC Retry, PwrMgt, MoreData flags to zero */ | |
473 | aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6)); | |
474 | /* A1 || A2 || A3 */ | |
475 | memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN); | |
476 | } | |
477 | ||
478 | ||
479 | static inline void bip_ipn_swap(u8 *d, const u8 *s) | |
480 | { | |
481 | *d++ = s[5]; | |
482 | *d++ = s[4]; | |
483 | *d++ = s[3]; | |
484 | *d++ = s[2]; | |
485 | *d++ = s[1]; | |
486 | *d = s[0]; | |
487 | } | |
488 | ||
489 | ||
490 | ieee80211_tx_result | |
491 | ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) | |
492 | { | |
493 | struct sk_buff *skb = tx->skb; | |
494 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); | |
495 | struct ieee80211_key *key = tx->key; | |
496 | struct ieee80211_mmie *mmie; | |
497 | u8 *pn, aad[20]; | |
498 | int i; | |
499 | ||
813d7669 | 500 | if (info->control.hw_key) |
765cb46a | 501 | return 0; |
765cb46a JM |
502 | |
503 | if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) | |
504 | return TX_DROP; | |
505 | ||
506 | mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie)); | |
507 | mmie->element_id = WLAN_EID_MMIE; | |
508 | mmie->length = sizeof(*mmie) - 2; | |
509 | mmie->key_id = cpu_to_le16(key->conf.keyidx); | |
510 | ||
511 | /* PN = PN + 1 */ | |
512 | pn = key->u.aes_cmac.tx_pn; | |
513 | ||
514 | for (i = sizeof(key->u.aes_cmac.tx_pn) - 1; i >= 0; i--) { | |
515 | pn[i]++; | |
516 | if (pn[i]) | |
517 | break; | |
518 | } | |
519 | bip_ipn_swap(mmie->sequence_number, pn); | |
520 | ||
521 | bip_aad(skb, aad); | |
522 | ||
523 | /* | |
524 | * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) | |
525 | */ | |
526 | ieee80211_aes_cmac(key->u.aes_cmac.tfm, key->u.aes_cmac.tx_crypto_buf, | |
527 | aad, skb->data + 24, skb->len - 24, mmie->mic); | |
528 | ||
529 | return TX_CONTINUE; | |
530 | } | |
531 | ||
532 | ||
533 | ieee80211_rx_result | |
534 | ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) | |
535 | { | |
536 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 537 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
765cb46a JM |
538 | struct ieee80211_key *key = rx->key; |
539 | struct ieee80211_mmie *mmie; | |
540 | u8 aad[20], mic[8], ipn[6]; | |
541 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
542 | ||
543 | if (!ieee80211_is_mgmt(hdr->frame_control)) | |
544 | return RX_CONTINUE; | |
545 | ||
765cb46a JM |
546 | if (skb->len < 24 + sizeof(*mmie)) |
547 | return RX_DROP_UNUSABLE; | |
548 | ||
549 | mmie = (struct ieee80211_mmie *) | |
550 | (skb->data + skb->len - sizeof(*mmie)); | |
551 | if (mmie->element_id != WLAN_EID_MMIE || | |
552 | mmie->length != sizeof(*mmie) - 2) | |
553 | return RX_DROP_UNUSABLE; /* Invalid MMIE */ | |
554 | ||
555 | bip_ipn_swap(ipn, mmie->sequence_number); | |
556 | ||
557 | if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { | |
558 | key->u.aes_cmac.replays++; | |
559 | return RX_DROP_UNUSABLE; | |
560 | } | |
561 | ||
eb9fb5b8 | 562 | if (!(status->flag & RX_FLAG_DECRYPTED)) { |
765cb46a JM |
563 | /* hardware didn't decrypt/verify MIC */ |
564 | bip_aad(skb, aad); | |
565 | ieee80211_aes_cmac(key->u.aes_cmac.tfm, | |
566 | key->u.aes_cmac.rx_crypto_buf, aad, | |
567 | skb->data + 24, skb->len - 24, mic); | |
568 | if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { | |
569 | key->u.aes_cmac.icverrors++; | |
570 | return RX_DROP_UNUSABLE; | |
571 | } | |
572 | } | |
573 | ||
574 | memcpy(key->u.aes_cmac.rx_pn, ipn, 6); | |
575 | ||
576 | /* Remove MMIE */ | |
577 | skb_trim(skb, skb->len - sizeof(*mmie)); | |
578 | ||
579 | return RX_CONTINUE; | |
580 | } |