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 | |
816c04fe CL |
90 | /* |
91 | * it makes no sense to check for MIC errors on anything other | |
92 | * than data frames. | |
93 | */ | |
94 | if (!ieee80211_is_data_present(hdr->frame_control)) | |
9ae54c84 | 95 | return RX_CONTINUE; |
f0706e82 | 96 | |
816c04fe CL |
97 | /* |
98 | * No way to verify the MIC if the hardware stripped it or | |
99 | * the IV with the key index. In this case we have solely rely | |
100 | * on the driver to set RX_FLAG_MMIC_ERROR in the event of a | |
101 | * MIC failure report. | |
102 | */ | |
103 | if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) { | |
104 | if (status->flag & RX_FLAG_MMIC_ERROR) | |
105 | goto mic_fail; | |
106 | ||
107 | if (!(status->flag & RX_FLAG_IV_STRIPPED)) | |
108 | goto update_iv; | |
109 | ||
110 | return RX_CONTINUE; | |
111 | } | |
112 | ||
113 | /* | |
114 | * Some hardware seems to generate Michael MIC failure reports; even | |
115 | * though, the frame was not encrypted with TKIP and therefore has no | |
116 | * MIC. Ignore the flag them to avoid triggering countermeasures. | |
117 | */ | |
97359d12 | 118 | if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || |
816c04fe | 119 | !(status->flag & RX_FLAG_DECRYPTED)) |
9ae54c84 | 120 | return RX_CONTINUE; |
f0706e82 | 121 | |
816c04fe CL |
122 | if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) { |
123 | /* | |
124 | * APs with pairwise keys should never receive Michael MIC | |
125 | * errors for non-zero keyidx because these are reserved for | |
126 | * group keys and only the AP is sending real multicast | |
127 | * frames in the BSS. ( | |
128 | */ | |
129 | return RX_DROP_UNUSABLE; | |
130 | } | |
131 | ||
132 | if (status->flag & RX_FLAG_MMIC_ERROR) | |
133 | goto mic_fail; | |
134 | ||
8e8862b7 HH |
135 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
136 | if (skb->len < hdrlen + MICHAEL_MIC_LEN) | |
e4c26add | 137 | return RX_DROP_UNUSABLE; |
f0706e82 | 138 | |
8e8862b7 HH |
139 | data = skb->data + hdrlen; |
140 | data_len = skb->len - hdrlen - MICHAEL_MIC_LEN; | |
747d753d | 141 | key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY]; |
8e8862b7 | 142 | michael_mic(key, hdr, data, data_len, mic); |
816c04fe CL |
143 | if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0) |
144 | goto mic_fail; | |
f0706e82 | 145 | |
f0706e82 JB |
146 | /* remove Michael MIC from payload */ |
147 | skb_trim(skb, skb->len - MICHAEL_MIC_LEN); | |
148 | ||
816c04fe | 149 | update_iv: |
50741ae0 | 150 | /* update IV in key information to be able to detect replays */ |
b0f76b33 HH |
151 | rx->key->u.tkip.rx[rx->queue].iv32 = rx->tkip_iv32; |
152 | rx->key->u.tkip.rx[rx->queue].iv16 = rx->tkip_iv16; | |
50741ae0 | 153 | |
9ae54c84 | 154 | return RX_CONTINUE; |
816c04fe CL |
155 | |
156 | mic_fail: | |
157 | mac80211_ev_michael_mic_failure(rx->sdata, rx->key->conf.keyidx, | |
158 | (void *) skb->data, NULL, GFP_ATOMIC); | |
159 | return RX_DROP_UNUSABLE; | |
f0706e82 JB |
160 | } |
161 | ||
162 | ||
e039fa4a | 163 | static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
f0706e82 JB |
164 | { |
165 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
166 | struct ieee80211_key *key = tx->key; | |
e039fa4a | 167 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
d5184cac HH |
168 | unsigned int hdrlen; |
169 | int len, tail; | |
f0706e82 JB |
170 | u8 *pos; |
171 | ||
813d7669 JB |
172 | if (info->control.hw_key && |
173 | !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) { | |
174 | /* hwaccel - with no need for software-generated IV */ | |
23c0752a | 175 | return 0; |
e039fa4a JB |
176 | } |
177 | ||
d5184cac | 178 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 JB |
179 | len = skb->len - hdrlen; |
180 | ||
813d7669 | 181 | if (info->control.hw_key) |
23c0752a | 182 | tail = 0; |
11a843b7 | 183 | else |
23c0752a JB |
184 | tail = TKIP_ICV_LEN; |
185 | ||
186 | if (WARN_ON(skb_tailroom(skb) < tail || | |
187 | skb_headroom(skb) < TKIP_IV_LEN)) | |
188 | return -1; | |
f0706e82 JB |
189 | |
190 | pos = skb_push(skb, TKIP_IV_LEN); | |
191 | memmove(pos, pos + TKIP_IV_LEN, hdrlen); | |
192 | pos += hdrlen; | |
193 | ||
194 | /* Increase IV for the frame */ | |
b0f76b33 HH |
195 | key->u.tkip.tx.iv16++; |
196 | if (key->u.tkip.tx.iv16 == 0) | |
197 | key->u.tkip.tx.iv32++; | |
f0706e82 | 198 | |
813d7669 | 199 | pos = ieee80211_tkip_add_iv(pos, key, key->u.tkip.tx.iv16); |
f0706e82 | 200 | |
813d7669 JB |
201 | /* hwaccel - with software IV */ |
202 | if (info->control.hw_key) | |
f0706e82 | 203 | return 0; |
f0706e82 JB |
204 | |
205 | /* Add room for ICV */ | |
206 | skb_put(skb, TKIP_ICV_LEN); | |
207 | ||
208 | hdr = (struct ieee80211_hdr *) skb->data; | |
3473187d JL |
209 | return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm, |
210 | key, pos, len, hdr->addr2); | |
f0706e82 JB |
211 | } |
212 | ||
213 | ||
9ae54c84 | 214 | ieee80211_tx_result |
5cf121c3 | 215 | ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx) |
f0706e82 | 216 | { |
f0706e82 | 217 | struct sk_buff *skb = tx->skb; |
f0706e82 | 218 | |
5cf121c3 | 219 | ieee80211_tx_set_protected(tx); |
f0706e82 | 220 | |
2de8e0d9 JB |
221 | do { |
222 | if (tkip_encrypt_skb(tx, skb) < 0) | |
223 | return TX_DROP; | |
224 | } while ((skb = skb->next)); | |
f0706e82 | 225 | |
9ae54c84 | 226 | return TX_CONTINUE; |
f0706e82 JB |
227 | } |
228 | ||
229 | ||
9ae54c84 | 230 | ieee80211_rx_result |
5cf121c3 | 231 | ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx) |
f0706e82 JB |
232 | { |
233 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; | |
747d753d | 234 | int hdrlen, res, hwaccel = 0; |
f0706e82 JB |
235 | struct ieee80211_key *key = rx->key; |
236 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 237 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
f0706e82 | 238 | |
d5184cac | 239 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 | 240 | |
c34498b9 | 241 | if (!ieee80211_is_data(hdr->frame_control)) |
9ae54c84 | 242 | return RX_CONTINUE; |
f0706e82 JB |
243 | |
244 | if (!rx->sta || skb->len - hdrlen < 12) | |
e4c26add | 245 | return RX_DROP_UNUSABLE; |
f0706e82 | 246 | |
dc1580dd JB |
247 | /* |
248 | * Let TKIP code verify IV, but skip decryption. | |
249 | * In the case where hardware checks the IV as well, | |
250 | * we don't even get here, see ieee80211_rx_h_decrypt() | |
251 | */ | |
252 | if (status->flag & RX_FLAG_DECRYPTED) | |
f0706e82 | 253 | hwaccel = 1; |
f0706e82 JB |
254 | |
255 | res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm, | |
256 | key, skb->data + hdrlen, | |
17741cdc | 257 | skb->len - hdrlen, rx->sta->sta.addr, |
9ae4fda3 | 258 | hdr->addr1, hwaccel, rx->queue, |
5cf121c3 JB |
259 | &rx->tkip_iv32, |
260 | &rx->tkip_iv16); | |
747d753d | 261 | if (res != TKIP_DECRYPT_OK) |
e4c26add | 262 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
263 | |
264 | /* Trim ICV */ | |
265 | skb_trim(skb, skb->len - TKIP_ICV_LEN); | |
266 | ||
267 | /* Remove IV */ | |
268 | memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen); | |
269 | skb_pull(skb, TKIP_IV_LEN); | |
270 | ||
9ae54c84 | 271 | return RX_CONTINUE; |
f0706e82 JB |
272 | } |
273 | ||
274 | ||
feccb466 | 275 | static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch, |
f0706e82 JB |
276 | int encrypted) |
277 | { | |
f14df804 | 278 | __le16 mask_fc; |
fb733336 | 279 | int a4_included, mgmt; |
f14df804 | 280 | u8 qos_tid; |
feccb466 | 281 | u8 *b_0, *aad; |
f14df804 HH |
282 | u16 data_len, len_a; |
283 | unsigned int hdrlen; | |
284 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; | |
f0706e82 | 285 | |
feccb466 HH |
286 | b_0 = scratch + 3 * AES_BLOCK_LEN; |
287 | aad = scratch + 4 * AES_BLOCK_LEN; | |
288 | ||
f14df804 | 289 | /* |
fb733336 | 290 | * Mask FC: zero subtype b4 b5 b6 (if not mgmt) |
f14df804 HH |
291 | * Retry, PwrMgt, MoreData; set Protected |
292 | */ | |
fb733336 | 293 | mgmt = ieee80211_is_mgmt(hdr->frame_control); |
f14df804 | 294 | mask_fc = hdr->frame_control; |
fb733336 | 295 | mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | |
f14df804 | 296 | IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); |
fb733336 JM |
297 | if (!mgmt) |
298 | mask_fc &= ~cpu_to_le16(0x0070); | |
f14df804 HH |
299 | mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); |
300 | ||
301 | hdrlen = ieee80211_hdrlen(hdr->frame_control); | |
302 | len_a = hdrlen - 2; | |
303 | a4_included = ieee80211_has_a4(hdr->frame_control); | |
f0706e82 | 304 | |
f14df804 HH |
305 | if (ieee80211_is_data_qos(hdr->frame_control)) |
306 | qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; | |
307 | else | |
308 | qos_tid = 0; | |
309 | ||
310 | data_len = skb->len - hdrlen - CCMP_HDR_LEN; | |
311 | if (encrypted) | |
312 | data_len -= CCMP_MIC_LEN; | |
313 | ||
314 | /* First block, b_0 */ | |
f0706e82 | 315 | b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */ |
fb733336 JM |
316 | /* Nonce: Nonce Flags | A2 | PN |
317 | * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7) | |
318 | */ | |
319 | b_0[1] = qos_tid | (mgmt << 4); | |
73e1f7c8 | 320 | memcpy(&b_0[2], hdr->addr2, ETH_ALEN); |
f0706e82 JB |
321 | memcpy(&b_0[8], pn, CCMP_PN_LEN); |
322 | /* l(m) */ | |
f14df804 | 323 | put_unaligned_be16(data_len, &b_0[14]); |
f0706e82 JB |
324 | |
325 | /* AAD (extra authenticate-only data) / masked 802.11 header | |
326 | * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ | |
f14df804 HH |
327 | put_unaligned_be16(len_a, &aad[0]); |
328 | put_unaligned(mask_fc, (__le16 *)&aad[2]); | |
73e1f7c8 | 329 | memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); |
f0706e82 JB |
330 | |
331 | /* Mask Seq#, leave Frag# */ | |
332 | aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; | |
333 | aad[23] = 0; | |
f14df804 | 334 | |
f0706e82 | 335 | if (a4_included) { |
73e1f7c8 | 336 | memcpy(&aad[24], hdr->addr4, ETH_ALEN); |
f14df804 | 337 | aad[30] = qos_tid; |
f0706e82 | 338 | aad[31] = 0; |
f14df804 | 339 | } else { |
73e1f7c8 | 340 | memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); |
f14df804 | 341 | aad[24] = qos_tid; |
f0706e82 JB |
342 | } |
343 | } | |
344 | ||
345 | ||
346 | static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) | |
347 | { | |
348 | hdr[0] = pn[5]; | |
349 | hdr[1] = pn[4]; | |
350 | hdr[2] = 0; | |
351 | hdr[3] = 0x20 | (key_id << 6); | |
352 | hdr[4] = pn[3]; | |
353 | hdr[5] = pn[2]; | |
354 | hdr[6] = pn[1]; | |
355 | hdr[7] = pn[0]; | |
356 | } | |
357 | ||
358 | ||
c6a1fa12 | 359 | static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr) |
f0706e82 JB |
360 | { |
361 | pn[0] = hdr[7]; | |
362 | pn[1] = hdr[6]; | |
363 | pn[2] = hdr[5]; | |
364 | pn[3] = hdr[4]; | |
365 | pn[4] = hdr[1]; | |
366 | pn[5] = hdr[0]; | |
f0706e82 JB |
367 | } |
368 | ||
369 | ||
e039fa4a | 370 | static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
f0706e82 JB |
371 | { |
372 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
373 | struct ieee80211_key *key = tx->key; | |
e039fa4a | 374 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
23c0752a | 375 | int hdrlen, len, tail; |
feccb466 | 376 | u8 *pos, *pn; |
f0706e82 JB |
377 | int i; |
378 | ||
813d7669 JB |
379 | if (info->control.hw_key && |
380 | !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) { | |
381 | /* | |
382 | * hwaccel has no need for preallocated room for CCMP | |
383 | * header or MIC fields | |
384 | */ | |
23c0752a | 385 | return 0; |
e039fa4a JB |
386 | } |
387 | ||
d5184cac | 388 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 JB |
389 | len = skb->len - hdrlen; |
390 | ||
813d7669 | 391 | if (info->control.hw_key) |
23c0752a | 392 | tail = 0; |
11a843b7 | 393 | else |
23c0752a JB |
394 | tail = CCMP_MIC_LEN; |
395 | ||
396 | if (WARN_ON(skb_tailroom(skb) < tail || | |
397 | skb_headroom(skb) < CCMP_HDR_LEN)) | |
398 | return -1; | |
f0706e82 JB |
399 | |
400 | pos = skb_push(skb, CCMP_HDR_LEN); | |
401 | memmove(pos, pos + CCMP_HDR_LEN, hdrlen); | |
402 | hdr = (struct ieee80211_hdr *) pos; | |
403 | pos += hdrlen; | |
404 | ||
405 | /* PN = PN + 1 */ | |
406 | pn = key->u.ccmp.tx_pn; | |
407 | ||
408 | for (i = CCMP_PN_LEN - 1; i >= 0; i--) { | |
409 | pn[i]++; | |
410 | if (pn[i]) | |
411 | break; | |
412 | } | |
413 | ||
8f20fc24 | 414 | ccmp_pn2hdr(pos, pn, key->conf.keyidx); |
f0706e82 | 415 | |
813d7669 JB |
416 | /* hwaccel - with software CCMP header */ |
417 | if (info->control.hw_key) | |
f0706e82 | 418 | return 0; |
f0706e82 JB |
419 | |
420 | pos += CCMP_HDR_LEN; | |
feccb466 HH |
421 | ccmp_special_blocks(skb, pn, key->u.ccmp.tx_crypto_buf, 0); |
422 | ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, key->u.ccmp.tx_crypto_buf, pos, len, | |
f0706e82 JB |
423 | pos, skb_put(skb, CCMP_MIC_LEN)); |
424 | ||
425 | return 0; | |
426 | } | |
427 | ||
428 | ||
9ae54c84 | 429 | ieee80211_tx_result |
5cf121c3 | 430 | ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx) |
f0706e82 | 431 | { |
f0706e82 | 432 | struct sk_buff *skb = tx->skb; |
f0706e82 | 433 | |
5cf121c3 | 434 | ieee80211_tx_set_protected(tx); |
f0706e82 | 435 | |
2de8e0d9 JB |
436 | do { |
437 | if (ccmp_encrypt_skb(tx, skb) < 0) | |
438 | return TX_DROP; | |
439 | } while ((skb = skb->next)); | |
f0706e82 | 440 | |
9ae54c84 | 441 | return TX_CONTINUE; |
f0706e82 JB |
442 | } |
443 | ||
444 | ||
9ae54c84 | 445 | ieee80211_rx_result |
5cf121c3 | 446 | ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx) |
f0706e82 | 447 | { |
c34498b9 | 448 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; |
f0706e82 JB |
449 | int hdrlen; |
450 | struct ieee80211_key *key = rx->key; | |
451 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 452 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
f0706e82 JB |
453 | u8 pn[CCMP_PN_LEN]; |
454 | int data_len; | |
9190252c | 455 | int queue; |
f0706e82 | 456 | |
d5184cac | 457 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 | 458 | |
fb733336 JM |
459 | if (!ieee80211_is_data(hdr->frame_control) && |
460 | !ieee80211_is_robust_mgmt_frame(hdr)) | |
9ae54c84 | 461 | return RX_CONTINUE; |
f0706e82 JB |
462 | |
463 | data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN; | |
464 | if (!rx->sta || data_len < 0) | |
e4c26add | 465 | return RX_DROP_UNUSABLE; |
f0706e82 | 466 | |
c6a1fa12 | 467 | ccmp_hdr2pn(pn, skb->data + hdrlen); |
f0706e82 | 468 | |
9190252c JM |
469 | queue = ieee80211_is_mgmt(hdr->frame_control) ? |
470 | NUM_RX_DATA_QUEUES : rx->queue; | |
471 | ||
472 | if (memcmp(pn, key->u.ccmp.rx_pn[queue], CCMP_PN_LEN) <= 0) { | |
f0706e82 | 473 | key->u.ccmp.replays++; |
e4c26add | 474 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
475 | } |
476 | ||
eb9fb5b8 | 477 | if (!(status->flag & RX_FLAG_DECRYPTED)) { |
7848ba7d | 478 | /* hardware didn't decrypt/verify MIC */ |
feccb466 | 479 | ccmp_special_blocks(skb, pn, key->u.ccmp.rx_crypto_buf, 1); |
f0706e82 JB |
480 | |
481 | if (ieee80211_aes_ccm_decrypt( | |
feccb466 | 482 | key->u.ccmp.tfm, key->u.ccmp.rx_crypto_buf, |
f0706e82 JB |
483 | skb->data + hdrlen + CCMP_HDR_LEN, data_len, |
484 | skb->data + skb->len - CCMP_MIC_LEN, | |
c6a1fa12 | 485 | skb->data + hdrlen + CCMP_HDR_LEN)) |
e4c26add | 486 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
487 | } |
488 | ||
9190252c | 489 | memcpy(key->u.ccmp.rx_pn[queue], pn, CCMP_PN_LEN); |
f0706e82 JB |
490 | |
491 | /* Remove CCMP header and MIC */ | |
492 | skb_trim(skb, skb->len - CCMP_MIC_LEN); | |
493 | memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen); | |
494 | skb_pull(skb, CCMP_HDR_LEN); | |
495 | ||
9ae54c84 | 496 | return RX_CONTINUE; |
f0706e82 | 497 | } |
765cb46a JM |
498 | |
499 | ||
500 | static void bip_aad(struct sk_buff *skb, u8 *aad) | |
501 | { | |
502 | /* BIP AAD: FC(masked) || A1 || A2 || A3 */ | |
503 | ||
504 | /* FC type/subtype */ | |
505 | aad[0] = skb->data[0]; | |
506 | /* Mask FC Retry, PwrMgt, MoreData flags to zero */ | |
507 | aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6)); | |
508 | /* A1 || A2 || A3 */ | |
509 | memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN); | |
510 | } | |
511 | ||
512 | ||
513 | static inline void bip_ipn_swap(u8 *d, const u8 *s) | |
514 | { | |
515 | *d++ = s[5]; | |
516 | *d++ = s[4]; | |
517 | *d++ = s[3]; | |
518 | *d++ = s[2]; | |
519 | *d++ = s[1]; | |
520 | *d = s[0]; | |
521 | } | |
522 | ||
523 | ||
524 | ieee80211_tx_result | |
525 | ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) | |
526 | { | |
527 | struct sk_buff *skb = tx->skb; | |
528 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); | |
529 | struct ieee80211_key *key = tx->key; | |
530 | struct ieee80211_mmie *mmie; | |
531 | u8 *pn, aad[20]; | |
532 | int i; | |
533 | ||
813d7669 | 534 | if (info->control.hw_key) |
765cb46a | 535 | return 0; |
765cb46a JM |
536 | |
537 | if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) | |
538 | return TX_DROP; | |
539 | ||
540 | mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie)); | |
541 | mmie->element_id = WLAN_EID_MMIE; | |
542 | mmie->length = sizeof(*mmie) - 2; | |
543 | mmie->key_id = cpu_to_le16(key->conf.keyidx); | |
544 | ||
545 | /* PN = PN + 1 */ | |
546 | pn = key->u.aes_cmac.tx_pn; | |
547 | ||
548 | for (i = sizeof(key->u.aes_cmac.tx_pn) - 1; i >= 0; i--) { | |
549 | pn[i]++; | |
550 | if (pn[i]) | |
551 | break; | |
552 | } | |
553 | bip_ipn_swap(mmie->sequence_number, pn); | |
554 | ||
555 | bip_aad(skb, aad); | |
556 | ||
557 | /* | |
558 | * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) | |
559 | */ | |
560 | ieee80211_aes_cmac(key->u.aes_cmac.tfm, key->u.aes_cmac.tx_crypto_buf, | |
561 | aad, skb->data + 24, skb->len - 24, mmie->mic); | |
562 | ||
563 | return TX_CONTINUE; | |
564 | } | |
565 | ||
566 | ||
567 | ieee80211_rx_result | |
568 | ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) | |
569 | { | |
570 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 571 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
765cb46a JM |
572 | struct ieee80211_key *key = rx->key; |
573 | struct ieee80211_mmie *mmie; | |
574 | u8 aad[20], mic[8], ipn[6]; | |
575 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
576 | ||
577 | if (!ieee80211_is_mgmt(hdr->frame_control)) | |
578 | return RX_CONTINUE; | |
579 | ||
765cb46a JM |
580 | if (skb->len < 24 + sizeof(*mmie)) |
581 | return RX_DROP_UNUSABLE; | |
582 | ||
583 | mmie = (struct ieee80211_mmie *) | |
584 | (skb->data + skb->len - sizeof(*mmie)); | |
585 | if (mmie->element_id != WLAN_EID_MMIE || | |
586 | mmie->length != sizeof(*mmie) - 2) | |
587 | return RX_DROP_UNUSABLE; /* Invalid MMIE */ | |
588 | ||
589 | bip_ipn_swap(ipn, mmie->sequence_number); | |
590 | ||
591 | if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { | |
592 | key->u.aes_cmac.replays++; | |
593 | return RX_DROP_UNUSABLE; | |
594 | } | |
595 | ||
eb9fb5b8 | 596 | if (!(status->flag & RX_FLAG_DECRYPTED)) { |
765cb46a JM |
597 | /* hardware didn't decrypt/verify MIC */ |
598 | bip_aad(skb, aad); | |
599 | ieee80211_aes_cmac(key->u.aes_cmac.tfm, | |
600 | key->u.aes_cmac.rx_crypto_buf, aad, | |
601 | skb->data + 24, skb->len - 24, mic); | |
602 | if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { | |
603 | key->u.aes_cmac.icverrors++; | |
604 | return RX_DROP_UNUSABLE; | |
605 | } | |
606 | } | |
607 | ||
608 | memcpy(key->u.aes_cmac.rx_pn, ipn, 6); | |
609 | ||
610 | /* Remove MMIE */ | |
611 | skb_trim(skb, skb->len - sizeof(*mmie)); | |
612 | ||
613 | return RX_CONTINUE; | |
614 | } |