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> |
aba83a0b | 18 | #include <crypto/aes.h> |
eb063c17 | 19 | |
f0706e82 JB |
20 | #include "ieee80211_i.h" |
21 | #include "michael.h" | |
22 | #include "tkip.h" | |
23 | #include "aes_ccm.h" | |
765cb46a | 24 | #include "aes_cmac.h" |
f0706e82 JB |
25 | #include "wpa.h" |
26 | ||
9ae54c84 | 27 | ieee80211_tx_result |
5cf121c3 | 28 | ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx) |
f0706e82 | 29 | { |
747d753d | 30 | u8 *data, *key, *mic; |
f0706e82 | 31 | size_t data_len; |
8e8862b7 HH |
32 | unsigned int hdrlen; |
33 | struct ieee80211_hdr *hdr; | |
f0706e82 | 34 | struct sk_buff *skb = tx->skb; |
813d7669 | 35 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
23c0752a | 36 | int tail; |
f0706e82 | 37 | |
c34498b9 | 38 | hdr = (struct ieee80211_hdr *)skb->data; |
97359d12 JB |
39 | if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || |
40 | skb->len < 24 || !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 | ||
681d1190 JM |
50 | if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) { |
51 | /* Need to use software crypto for the test */ | |
52 | info->control.hw_key = NULL; | |
53 | } | |
54 | ||
813d7669 | 55 | if (info->control.hw_key && |
a26eb27a JB |
56 | (info->flags & IEEE80211_TX_CTL_DONTFRAG || |
57 | tx->local->ops->set_frag_threshold) && | |
813d7669 JB |
58 | !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) { |
59 | /* hwaccel - with no need for SW-generated MMIC */ | |
9ae54c84 | 60 | return TX_CONTINUE; |
f0706e82 JB |
61 | } |
62 | ||
23c0752a | 63 | tail = MICHAEL_MIC_LEN; |
813d7669 | 64 | if (!info->control.hw_key) |
23c0752a JB |
65 | tail += TKIP_ICV_LEN; |
66 | ||
67 | if (WARN_ON(skb_tailroom(skb) < tail || | |
68 | skb_headroom(skb) < TKIP_IV_LEN)) | |
69 | return TX_DROP; | |
f0706e82 | 70 | |
747d753d | 71 | key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY]; |
f0706e82 | 72 | mic = skb_put(skb, MICHAEL_MIC_LEN); |
8e8862b7 | 73 | michael_mic(key, hdr, data, data_len, mic); |
681d1190 JM |
74 | if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) |
75 | mic[0]++; | |
f0706e82 | 76 | |
9ae54c84 | 77 | return TX_CONTINUE; |
f0706e82 JB |
78 | } |
79 | ||
80 | ||
9ae54c84 | 81 | ieee80211_rx_result |
5cf121c3 | 82 | ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) |
f0706e82 | 83 | { |
747d753d | 84 | u8 *data, *key = NULL; |
f0706e82 | 85 | size_t data_len; |
8e8862b7 | 86 | unsigned int hdrlen; |
f0706e82 JB |
87 | u8 mic[MICHAEL_MIC_LEN]; |
88 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 JB |
89 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
90 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; | |
f0706e82 | 91 | |
816c04fe CL |
92 | /* |
93 | * it makes no sense to check for MIC errors on anything other | |
94 | * than data frames. | |
95 | */ | |
96 | if (!ieee80211_is_data_present(hdr->frame_control)) | |
9ae54c84 | 97 | return RX_CONTINUE; |
f0706e82 | 98 | |
816c04fe CL |
99 | /* |
100 | * No way to verify the MIC if the hardware stripped it or | |
101 | * the IV with the key index. In this case we have solely rely | |
102 | * on the driver to set RX_FLAG_MMIC_ERROR in the event of a | |
103 | * MIC failure report. | |
104 | */ | |
105 | if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) { | |
106 | if (status->flag & RX_FLAG_MMIC_ERROR) | |
107 | goto mic_fail; | |
108 | ||
109 | if (!(status->flag & RX_FLAG_IV_STRIPPED)) | |
110 | goto update_iv; | |
111 | ||
112 | return RX_CONTINUE; | |
113 | } | |
114 | ||
115 | /* | |
116 | * Some hardware seems to generate Michael MIC failure reports; even | |
117 | * though, the frame was not encrypted with TKIP and therefore has no | |
118 | * MIC. Ignore the flag them to avoid triggering countermeasures. | |
119 | */ | |
97359d12 | 120 | if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || |
816c04fe | 121 | !(status->flag & RX_FLAG_DECRYPTED)) |
9ae54c84 | 122 | return RX_CONTINUE; |
f0706e82 | 123 | |
816c04fe CL |
124 | if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) { |
125 | /* | |
126 | * APs with pairwise keys should never receive Michael MIC | |
127 | * errors for non-zero keyidx because these are reserved for | |
128 | * group keys and only the AP is sending real multicast | |
129 | * frames in the BSS. ( | |
130 | */ | |
131 | return RX_DROP_UNUSABLE; | |
132 | } | |
133 | ||
134 | if (status->flag & RX_FLAG_MMIC_ERROR) | |
135 | goto mic_fail; | |
136 | ||
8e8862b7 HH |
137 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
138 | if (skb->len < hdrlen + MICHAEL_MIC_LEN) | |
e4c26add | 139 | return RX_DROP_UNUSABLE; |
f0706e82 | 140 | |
8e8862b7 HH |
141 | data = skb->data + hdrlen; |
142 | data_len = skb->len - hdrlen - MICHAEL_MIC_LEN; | |
747d753d | 143 | key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY]; |
8e8862b7 | 144 | michael_mic(key, hdr, data, data_len, mic); |
816c04fe CL |
145 | if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0) |
146 | goto mic_fail; | |
f0706e82 | 147 | |
f0706e82 JB |
148 | /* remove Michael MIC from payload */ |
149 | skb_trim(skb, skb->len - MICHAEL_MIC_LEN); | |
150 | ||
816c04fe | 151 | update_iv: |
50741ae0 | 152 | /* update IV in key information to be able to detect replays */ |
9e26297a JB |
153 | rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32; |
154 | rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16; | |
50741ae0 | 155 | |
9ae54c84 | 156 | return RX_CONTINUE; |
816c04fe CL |
157 | |
158 | mic_fail: | |
a66b98db AN |
159 | /* |
160 | * In some cases the key can be unset - e.g. a multicast packet, in | |
161 | * a driver that supports HW encryption. Send up the key idx only if | |
162 | * the key is set. | |
163 | */ | |
164 | mac80211_ev_michael_mic_failure(rx->sdata, | |
165 | rx->key ? rx->key->conf.keyidx : -1, | |
816c04fe CL |
166 | (void *) skb->data, NULL, GFP_ATOMIC); |
167 | return RX_DROP_UNUSABLE; | |
f0706e82 JB |
168 | } |
169 | ||
170 | ||
e039fa4a | 171 | static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
f0706e82 JB |
172 | { |
173 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
174 | struct ieee80211_key *key = tx->key; | |
e039fa4a | 175 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
523b02ea | 176 | unsigned long flags; |
d5184cac HH |
177 | unsigned int hdrlen; |
178 | int len, tail; | |
f0706e82 JB |
179 | u8 *pos; |
180 | ||
813d7669 JB |
181 | if (info->control.hw_key && |
182 | !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) { | |
183 | /* hwaccel - with no need for software-generated IV */ | |
23c0752a | 184 | return 0; |
e039fa4a JB |
185 | } |
186 | ||
d5184cac | 187 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 JB |
188 | len = skb->len - hdrlen; |
189 | ||
813d7669 | 190 | if (info->control.hw_key) |
23c0752a | 191 | tail = 0; |
11a843b7 | 192 | else |
23c0752a JB |
193 | tail = TKIP_ICV_LEN; |
194 | ||
195 | if (WARN_ON(skb_tailroom(skb) < tail || | |
196 | skb_headroom(skb) < TKIP_IV_LEN)) | |
197 | return -1; | |
f0706e82 JB |
198 | |
199 | pos = skb_push(skb, TKIP_IV_LEN); | |
200 | memmove(pos, pos + TKIP_IV_LEN, hdrlen); | |
201 | pos += hdrlen; | |
202 | ||
203 | /* Increase IV for the frame */ | |
523b02ea | 204 | spin_lock_irqsave(&key->u.tkip.txlock, flags); |
b0f76b33 HH |
205 | key->u.tkip.tx.iv16++; |
206 | if (key->u.tkip.tx.iv16 == 0) | |
207 | key->u.tkip.tx.iv32++; | |
523b02ea JB |
208 | pos = ieee80211_tkip_add_iv(pos, key); |
209 | spin_unlock_irqrestore(&key->u.tkip.txlock, flags); | |
f0706e82 | 210 | |
813d7669 JB |
211 | /* hwaccel - with software IV */ |
212 | if (info->control.hw_key) | |
f0706e82 | 213 | return 0; |
f0706e82 JB |
214 | |
215 | /* Add room for ICV */ | |
216 | skb_put(skb, TKIP_ICV_LEN); | |
217 | ||
3473187d | 218 | return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm, |
523b02ea | 219 | key, skb, pos, len); |
f0706e82 JB |
220 | } |
221 | ||
222 | ||
9ae54c84 | 223 | ieee80211_tx_result |
5cf121c3 | 224 | ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx) |
f0706e82 | 225 | { |
252b86c4 | 226 | struct sk_buff *skb; |
f0706e82 | 227 | |
5cf121c3 | 228 | ieee80211_tx_set_protected(tx); |
f0706e82 | 229 | |
252b86c4 | 230 | skb_queue_walk(&tx->skbs, skb) { |
2de8e0d9 JB |
231 | if (tkip_encrypt_skb(tx, skb) < 0) |
232 | return TX_DROP; | |
252b86c4 | 233 | } |
f0706e82 | 234 | |
9ae54c84 | 235 | return TX_CONTINUE; |
f0706e82 JB |
236 | } |
237 | ||
238 | ||
9ae54c84 | 239 | ieee80211_rx_result |
5cf121c3 | 240 | ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx) |
f0706e82 JB |
241 | { |
242 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; | |
747d753d | 243 | int hdrlen, res, hwaccel = 0; |
f0706e82 JB |
244 | struct ieee80211_key *key = rx->key; |
245 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 246 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
f0706e82 | 247 | |
d5184cac | 248 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 | 249 | |
c34498b9 | 250 | if (!ieee80211_is_data(hdr->frame_control)) |
9ae54c84 | 251 | return RX_CONTINUE; |
f0706e82 JB |
252 | |
253 | if (!rx->sta || skb->len - hdrlen < 12) | |
e4c26add | 254 | return RX_DROP_UNUSABLE; |
f0706e82 | 255 | |
dc1580dd JB |
256 | /* |
257 | * Let TKIP code verify IV, but skip decryption. | |
258 | * In the case where hardware checks the IV as well, | |
259 | * we don't even get here, see ieee80211_rx_h_decrypt() | |
260 | */ | |
261 | if (status->flag & RX_FLAG_DECRYPTED) | |
f0706e82 | 262 | hwaccel = 1; |
f0706e82 JB |
263 | |
264 | res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm, | |
265 | key, skb->data + hdrlen, | |
17741cdc | 266 | skb->len - hdrlen, rx->sta->sta.addr, |
9e26297a | 267 | hdr->addr1, hwaccel, rx->security_idx, |
5cf121c3 JB |
268 | &rx->tkip_iv32, |
269 | &rx->tkip_iv16); | |
747d753d | 270 | if (res != TKIP_DECRYPT_OK) |
e4c26add | 271 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
272 | |
273 | /* Trim ICV */ | |
274 | skb_trim(skb, skb->len - TKIP_ICV_LEN); | |
275 | ||
276 | /* Remove IV */ | |
277 | memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen); | |
278 | skb_pull(skb, TKIP_IV_LEN); | |
279 | ||
9ae54c84 | 280 | return RX_CONTINUE; |
f0706e82 JB |
281 | } |
282 | ||
283 | ||
feccb466 | 284 | static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch, |
f0706e82 JB |
285 | int encrypted) |
286 | { | |
f14df804 | 287 | __le16 mask_fc; |
fb733336 | 288 | int a4_included, mgmt; |
f14df804 | 289 | u8 qos_tid; |
feccb466 | 290 | u8 *b_0, *aad; |
f14df804 HH |
291 | u16 data_len, len_a; |
292 | unsigned int hdrlen; | |
293 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; | |
f0706e82 | 294 | |
0cd20a27 | 295 | memset(scratch, 0, 6 * AES_BLOCK_SIZE); |
aba83a0b | 296 | |
0cd20a27 JB |
297 | b_0 = scratch + 3 * AES_BLOCK_SIZE; |
298 | aad = scratch + 4 * AES_BLOCK_SIZE; | |
feccb466 | 299 | |
f14df804 | 300 | /* |
fb733336 | 301 | * Mask FC: zero subtype b4 b5 b6 (if not mgmt) |
f14df804 HH |
302 | * Retry, PwrMgt, MoreData; set Protected |
303 | */ | |
fb733336 | 304 | mgmt = ieee80211_is_mgmt(hdr->frame_control); |
f14df804 | 305 | mask_fc = hdr->frame_control; |
fb733336 | 306 | mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | |
f14df804 | 307 | IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); |
fb733336 JM |
308 | if (!mgmt) |
309 | mask_fc &= ~cpu_to_le16(0x0070); | |
f14df804 HH |
310 | mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); |
311 | ||
312 | hdrlen = ieee80211_hdrlen(hdr->frame_control); | |
313 | len_a = hdrlen - 2; | |
314 | a4_included = ieee80211_has_a4(hdr->frame_control); | |
f0706e82 | 315 | |
f14df804 HH |
316 | if (ieee80211_is_data_qos(hdr->frame_control)) |
317 | qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; | |
318 | else | |
319 | qos_tid = 0; | |
320 | ||
321 | data_len = skb->len - hdrlen - CCMP_HDR_LEN; | |
322 | if (encrypted) | |
323 | data_len -= CCMP_MIC_LEN; | |
324 | ||
325 | /* First block, b_0 */ | |
f0706e82 | 326 | b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */ |
fb733336 JM |
327 | /* Nonce: Nonce Flags | A2 | PN |
328 | * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7) | |
329 | */ | |
330 | b_0[1] = qos_tid | (mgmt << 4); | |
73e1f7c8 | 331 | memcpy(&b_0[2], hdr->addr2, ETH_ALEN); |
f0706e82 JB |
332 | memcpy(&b_0[8], pn, CCMP_PN_LEN); |
333 | /* l(m) */ | |
f14df804 | 334 | put_unaligned_be16(data_len, &b_0[14]); |
f0706e82 JB |
335 | |
336 | /* AAD (extra authenticate-only data) / masked 802.11 header | |
337 | * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ | |
f14df804 HH |
338 | put_unaligned_be16(len_a, &aad[0]); |
339 | put_unaligned(mask_fc, (__le16 *)&aad[2]); | |
73e1f7c8 | 340 | memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); |
f0706e82 JB |
341 | |
342 | /* Mask Seq#, leave Frag# */ | |
343 | aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; | |
344 | aad[23] = 0; | |
f14df804 | 345 | |
f0706e82 | 346 | if (a4_included) { |
73e1f7c8 | 347 | memcpy(&aad[24], hdr->addr4, ETH_ALEN); |
f14df804 | 348 | aad[30] = qos_tid; |
f0706e82 | 349 | aad[31] = 0; |
f14df804 | 350 | } else { |
73e1f7c8 | 351 | memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); |
f14df804 | 352 | aad[24] = qos_tid; |
f0706e82 JB |
353 | } |
354 | } | |
355 | ||
356 | ||
357 | static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) | |
358 | { | |
359 | hdr[0] = pn[5]; | |
360 | hdr[1] = pn[4]; | |
361 | hdr[2] = 0; | |
362 | hdr[3] = 0x20 | (key_id << 6); | |
363 | hdr[4] = pn[3]; | |
364 | hdr[5] = pn[2]; | |
365 | hdr[6] = pn[1]; | |
366 | hdr[7] = pn[0]; | |
367 | } | |
368 | ||
369 | ||
c6a1fa12 | 370 | static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr) |
f0706e82 JB |
371 | { |
372 | pn[0] = hdr[7]; | |
373 | pn[1] = hdr[6]; | |
374 | pn[2] = hdr[5]; | |
375 | pn[3] = hdr[4]; | |
376 | pn[4] = hdr[1]; | |
377 | pn[5] = hdr[0]; | |
f0706e82 JB |
378 | } |
379 | ||
380 | ||
e039fa4a | 381 | static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) |
f0706e82 JB |
382 | { |
383 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
384 | struct ieee80211_key *key = tx->key; | |
e039fa4a | 385 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); |
23c0752a | 386 | int hdrlen, len, tail; |
aba83a0b JB |
387 | u8 *pos; |
388 | u8 pn[6]; | |
389 | u64 pn64; | |
0cd20a27 | 390 | u8 scratch[6 * AES_BLOCK_SIZE]; |
f0706e82 | 391 | |
813d7669 | 392 | if (info->control.hw_key && |
077a9154 AN |
393 | !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && |
394 | !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) { | |
813d7669 JB |
395 | /* |
396 | * hwaccel has no need for preallocated room for CCMP | |
397 | * header or MIC fields | |
398 | */ | |
23c0752a | 399 | return 0; |
e039fa4a JB |
400 | } |
401 | ||
d5184cac | 402 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 JB |
403 | len = skb->len - hdrlen; |
404 | ||
813d7669 | 405 | if (info->control.hw_key) |
23c0752a | 406 | tail = 0; |
11a843b7 | 407 | else |
23c0752a JB |
408 | tail = CCMP_MIC_LEN; |
409 | ||
410 | if (WARN_ON(skb_tailroom(skb) < tail || | |
411 | skb_headroom(skb) < CCMP_HDR_LEN)) | |
412 | return -1; | |
f0706e82 JB |
413 | |
414 | pos = skb_push(skb, CCMP_HDR_LEN); | |
415 | memmove(pos, pos + CCMP_HDR_LEN, hdrlen); | |
077a9154 AN |
416 | |
417 | /* the HW only needs room for the IV, but not the actual IV */ | |
e0830f71 AN |
418 | if (info->control.hw_key && |
419 | (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) | |
077a9154 AN |
420 | return 0; |
421 | ||
f0706e82 JB |
422 | hdr = (struct ieee80211_hdr *) pos; |
423 | pos += hdrlen; | |
424 | ||
aba83a0b | 425 | pn64 = atomic64_inc_return(&key->u.ccmp.tx_pn); |
f0706e82 | 426 | |
aba83a0b JB |
427 | pn[5] = pn64; |
428 | pn[4] = pn64 >> 8; | |
429 | pn[3] = pn64 >> 16; | |
430 | pn[2] = pn64 >> 24; | |
431 | pn[1] = pn64 >> 32; | |
432 | pn[0] = pn64 >> 40; | |
f0706e82 | 433 | |
8f20fc24 | 434 | ccmp_pn2hdr(pos, pn, key->conf.keyidx); |
f0706e82 | 435 | |
813d7669 JB |
436 | /* hwaccel - with software CCMP header */ |
437 | if (info->control.hw_key) | |
f0706e82 | 438 | return 0; |
f0706e82 JB |
439 | |
440 | pos += CCMP_HDR_LEN; | |
aba83a0b JB |
441 | ccmp_special_blocks(skb, pn, scratch, 0); |
442 | ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, pos, len, | |
f0706e82 JB |
443 | pos, skb_put(skb, CCMP_MIC_LEN)); |
444 | ||
445 | return 0; | |
446 | } | |
447 | ||
448 | ||
9ae54c84 | 449 | ieee80211_tx_result |
5cf121c3 | 450 | ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx) |
f0706e82 | 451 | { |
252b86c4 | 452 | struct sk_buff *skb; |
f0706e82 | 453 | |
5cf121c3 | 454 | ieee80211_tx_set_protected(tx); |
f0706e82 | 455 | |
252b86c4 | 456 | skb_queue_walk(&tx->skbs, skb) { |
2de8e0d9 JB |
457 | if (ccmp_encrypt_skb(tx, skb) < 0) |
458 | return TX_DROP; | |
252b86c4 | 459 | } |
f0706e82 | 460 | |
9ae54c84 | 461 | return TX_CONTINUE; |
f0706e82 JB |
462 | } |
463 | ||
464 | ||
9ae54c84 | 465 | ieee80211_rx_result |
5cf121c3 | 466 | ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx) |
f0706e82 | 467 | { |
c34498b9 | 468 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; |
f0706e82 JB |
469 | int hdrlen; |
470 | struct ieee80211_key *key = rx->key; | |
471 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 472 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
f0706e82 JB |
473 | u8 pn[CCMP_PN_LEN]; |
474 | int data_len; | |
9190252c | 475 | int queue; |
f0706e82 | 476 | |
d5184cac | 477 | hdrlen = ieee80211_hdrlen(hdr->frame_control); |
f0706e82 | 478 | |
fb733336 JM |
479 | if (!ieee80211_is_data(hdr->frame_control) && |
480 | !ieee80211_is_robust_mgmt_frame(hdr)) | |
9ae54c84 | 481 | return RX_CONTINUE; |
f0706e82 JB |
482 | |
483 | data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN; | |
484 | if (!rx->sta || data_len < 0) | |
e4c26add | 485 | return RX_DROP_UNUSABLE; |
f0706e82 | 486 | |
c6a1fa12 | 487 | ccmp_hdr2pn(pn, skb->data + hdrlen); |
f0706e82 | 488 | |
9e26297a | 489 | queue = rx->security_idx; |
9190252c JM |
490 | |
491 | if (memcmp(pn, key->u.ccmp.rx_pn[queue], CCMP_PN_LEN) <= 0) { | |
f0706e82 | 492 | key->u.ccmp.replays++; |
e4c26add | 493 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
494 | } |
495 | ||
eb9fb5b8 | 496 | if (!(status->flag & RX_FLAG_DECRYPTED)) { |
0cd20a27 | 497 | u8 scratch[6 * AES_BLOCK_SIZE]; |
7848ba7d | 498 | /* hardware didn't decrypt/verify MIC */ |
aba83a0b | 499 | ccmp_special_blocks(skb, pn, scratch, 1); |
f0706e82 JB |
500 | |
501 | if (ieee80211_aes_ccm_decrypt( | |
aba83a0b | 502 | key->u.ccmp.tfm, scratch, |
f0706e82 JB |
503 | skb->data + hdrlen + CCMP_HDR_LEN, data_len, |
504 | skb->data + skb->len - CCMP_MIC_LEN, | |
c6a1fa12 | 505 | skb->data + hdrlen + CCMP_HDR_LEN)) |
e4c26add | 506 | return RX_DROP_UNUSABLE; |
f0706e82 JB |
507 | } |
508 | ||
9190252c | 509 | memcpy(key->u.ccmp.rx_pn[queue], pn, CCMP_PN_LEN); |
f0706e82 JB |
510 | |
511 | /* Remove CCMP header and MIC */ | |
512 | skb_trim(skb, skb->len - CCMP_MIC_LEN); | |
513 | memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen); | |
514 | skb_pull(skb, CCMP_HDR_LEN); | |
515 | ||
9ae54c84 | 516 | return RX_CONTINUE; |
f0706e82 | 517 | } |
765cb46a JM |
518 | |
519 | ||
520 | static void bip_aad(struct sk_buff *skb, u8 *aad) | |
521 | { | |
522 | /* BIP AAD: FC(masked) || A1 || A2 || A3 */ | |
523 | ||
524 | /* FC type/subtype */ | |
525 | aad[0] = skb->data[0]; | |
526 | /* Mask FC Retry, PwrMgt, MoreData flags to zero */ | |
527 | aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6)); | |
528 | /* A1 || A2 || A3 */ | |
529 | memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN); | |
530 | } | |
531 | ||
532 | ||
75396ae6 JB |
533 | static inline void bip_ipn_set64(u8 *d, u64 pn) |
534 | { | |
535 | *d++ = pn; | |
536 | *d++ = pn >> 8; | |
537 | *d++ = pn >> 16; | |
538 | *d++ = pn >> 24; | |
539 | *d++ = pn >> 32; | |
540 | *d = pn >> 40; | |
541 | } | |
542 | ||
765cb46a JM |
543 | static inline void bip_ipn_swap(u8 *d, const u8 *s) |
544 | { | |
545 | *d++ = s[5]; | |
546 | *d++ = s[4]; | |
547 | *d++ = s[3]; | |
548 | *d++ = s[2]; | |
549 | *d++ = s[1]; | |
550 | *d = s[0]; | |
551 | } | |
552 | ||
553 | ||
554 | ieee80211_tx_result | |
555 | ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) | |
556 | { | |
252b86c4 JB |
557 | struct sk_buff *skb; |
558 | struct ieee80211_tx_info *info; | |
765cb46a JM |
559 | struct ieee80211_key *key = tx->key; |
560 | struct ieee80211_mmie *mmie; | |
75396ae6 JB |
561 | u8 aad[20]; |
562 | u64 pn64; | |
765cb46a | 563 | |
252b86c4 JB |
564 | if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) |
565 | return TX_DROP; | |
566 | ||
567 | skb = skb_peek(&tx->skbs); | |
568 | ||
569 | info = IEEE80211_SKB_CB(skb); | |
570 | ||
813d7669 | 571 | if (info->control.hw_key) |
252b86c4 | 572 | return TX_CONTINUE; |
765cb46a JM |
573 | |
574 | if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) | |
575 | return TX_DROP; | |
576 | ||
577 | mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie)); | |
578 | mmie->element_id = WLAN_EID_MMIE; | |
579 | mmie->length = sizeof(*mmie) - 2; | |
580 | mmie->key_id = cpu_to_le16(key->conf.keyidx); | |
581 | ||
582 | /* PN = PN + 1 */ | |
75396ae6 | 583 | pn64 = atomic64_inc_return(&key->u.aes_cmac.tx_pn); |
765cb46a | 584 | |
75396ae6 | 585 | bip_ipn_set64(mmie->sequence_number, pn64); |
765cb46a JM |
586 | |
587 | bip_aad(skb, aad); | |
588 | ||
589 | /* | |
590 | * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) | |
591 | */ | |
75396ae6 JB |
592 | ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, |
593 | skb->data + 24, skb->len - 24, mmie->mic); | |
765cb46a JM |
594 | |
595 | return TX_CONTINUE; | |
596 | } | |
597 | ||
598 | ||
599 | ieee80211_rx_result | |
600 | ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) | |
601 | { | |
602 | struct sk_buff *skb = rx->skb; | |
eb9fb5b8 | 603 | struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); |
765cb46a JM |
604 | struct ieee80211_key *key = rx->key; |
605 | struct ieee80211_mmie *mmie; | |
606 | u8 aad[20], mic[8], ipn[6]; | |
607 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
608 | ||
609 | if (!ieee80211_is_mgmt(hdr->frame_control)) | |
610 | return RX_CONTINUE; | |
611 | ||
765cb46a JM |
612 | if (skb->len < 24 + sizeof(*mmie)) |
613 | return RX_DROP_UNUSABLE; | |
614 | ||
615 | mmie = (struct ieee80211_mmie *) | |
616 | (skb->data + skb->len - sizeof(*mmie)); | |
617 | if (mmie->element_id != WLAN_EID_MMIE || | |
618 | mmie->length != sizeof(*mmie) - 2) | |
619 | return RX_DROP_UNUSABLE; /* Invalid MMIE */ | |
620 | ||
621 | bip_ipn_swap(ipn, mmie->sequence_number); | |
622 | ||
623 | if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { | |
624 | key->u.aes_cmac.replays++; | |
625 | return RX_DROP_UNUSABLE; | |
626 | } | |
627 | ||
eb9fb5b8 | 628 | if (!(status->flag & RX_FLAG_DECRYPTED)) { |
765cb46a JM |
629 | /* hardware didn't decrypt/verify MIC */ |
630 | bip_aad(skb, aad); | |
75396ae6 | 631 | ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, |
765cb46a JM |
632 | skb->data + 24, skb->len - 24, mic); |
633 | if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { | |
634 | key->u.aes_cmac.icverrors++; | |
635 | return RX_DROP_UNUSABLE; | |
636 | } | |
637 | } | |
638 | ||
639 | memcpy(key->u.aes_cmac.rx_pn, ipn, 6); | |
640 | ||
641 | /* Remove MMIE */ | |
642 | skb_trim(skb, skb->len - sizeof(*mmie)); | |
643 | ||
644 | return RX_CONTINUE; | |
645 | } |