Commit | Line | Data |
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b453872c JG |
1 | /* |
2 | * Host AP crypt: host-based TKIP encryption implementation for Host AP driver | |
3 | * | |
85d32e7b | 4 | * Copyright (c) 2003-2004, Jouni Malinen <j@w1.fi> |
b453872c JG |
5 | * |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. See README and COPYING for | |
9 | * more details. | |
10 | */ | |
11 | ||
f12cc209 | 12 | #include <linux/err.h> |
b453872c JG |
13 | #include <linux/module.h> |
14 | #include <linux/init.h> | |
15 | #include <linux/slab.h> | |
16 | #include <linux/random.h> | |
17 | #include <linux/skbuff.h> | |
18 | #include <linux/netdevice.h> | |
d7fe0f24 | 19 | #include <linux/mm.h> |
b453872c JG |
20 | #include <linux/if_ether.h> |
21 | #include <linux/if_arp.h> | |
22 | #include <asm/string.h> | |
23 | ||
24 | #include <net/ieee80211.h> | |
25 | ||
b453872c JG |
26 | #include <linux/crypto.h> |
27 | #include <asm/scatterlist.h> | |
28 | #include <linux/crc32.h> | |
29 | ||
30 | MODULE_AUTHOR("Jouni Malinen"); | |
31 | MODULE_DESCRIPTION("Host AP crypt: TKIP"); | |
32 | MODULE_LICENSE("GPL"); | |
33 | ||
34 | struct ieee80211_tkip_data { | |
35 | #define TKIP_KEY_LEN 32 | |
36 | u8 key[TKIP_KEY_LEN]; | |
37 | int key_set; | |
38 | ||
39 | u32 tx_iv32; | |
40 | u16 tx_iv16; | |
41 | u16 tx_ttak[5]; | |
42 | int tx_phase1_done; | |
43 | ||
44 | u32 rx_iv32; | |
45 | u16 rx_iv16; | |
46 | u16 rx_ttak[5]; | |
47 | int rx_phase1_done; | |
48 | u32 rx_iv32_new; | |
49 | u16 rx_iv16_new; | |
50 | ||
51 | u32 dot11RSNAStatsTKIPReplays; | |
52 | u32 dot11RSNAStatsTKIPICVErrors; | |
53 | u32 dot11RSNAStatsTKIPLocalMICFailures; | |
54 | ||
55 | int key_idx; | |
56 | ||
28eb177d JG |
57 | struct crypto_blkcipher *rx_tfm_arc4; |
58 | struct crypto_hash *rx_tfm_michael; | |
59 | struct crypto_blkcipher *tx_tfm_arc4; | |
60 | struct crypto_hash *tx_tfm_michael; | |
b453872c JG |
61 | |
62 | /* scratch buffers for virt_to_page() (crypto API) */ | |
63 | u8 rx_hdr[16], tx_hdr[16]; | |
20d64713 | 64 | |
6eb6edf0 | 65 | unsigned long flags; |
b453872c JG |
66 | }; |
67 | ||
6eb6edf0 JK |
68 | static unsigned long ieee80211_tkip_set_flags(unsigned long flags, void *priv) |
69 | { | |
70 | struct ieee80211_tkip_data *_priv = priv; | |
71 | unsigned long old_flags = _priv->flags; | |
72 | _priv->flags = flags; | |
73 | return old_flags; | |
74 | } | |
75 | ||
76 | static unsigned long ieee80211_tkip_get_flags(void *priv) | |
77 | { | |
78 | struct ieee80211_tkip_data *_priv = priv; | |
79 | return _priv->flags; | |
80 | } | |
81 | ||
82 | static void *ieee80211_tkip_init(int key_idx) | |
b453872c JG |
83 | { |
84 | struct ieee80211_tkip_data *priv; | |
85 | ||
8aa914b7 | 86 | priv = kzalloc(sizeof(*priv), GFP_ATOMIC); |
b453872c JG |
87 | if (priv == NULL) |
88 | goto fail; | |
20d64713 | 89 | |
b453872c JG |
90 | priv->key_idx = key_idx; |
91 | ||
28eb177d | 92 | priv->tx_tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, |
f12cc209 | 93 | CRYPTO_ALG_ASYNC); |
28eb177d | 94 | if (IS_ERR(priv->tx_tfm_arc4)) { |
b453872c JG |
95 | printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate " |
96 | "crypto API arc4\n"); | |
18379879 | 97 | priv->tx_tfm_arc4 = NULL; |
b453872c JG |
98 | goto fail; |
99 | } | |
100 | ||
28eb177d JG |
101 | priv->tx_tfm_michael = crypto_alloc_hash("michael_mic", 0, |
102 | CRYPTO_ALG_ASYNC); | |
103 | if (IS_ERR(priv->tx_tfm_michael)) { | |
5a656949 ZY |
104 | printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate " |
105 | "crypto API michael_mic\n"); | |
18379879 | 106 | priv->tx_tfm_michael = NULL; |
5a656949 ZY |
107 | goto fail; |
108 | } | |
109 | ||
28eb177d JG |
110 | priv->rx_tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, |
111 | CRYPTO_ALG_ASYNC); | |
112 | if (IS_ERR(priv->rx_tfm_arc4)) { | |
5a656949 ZY |
113 | printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate " |
114 | "crypto API arc4\n"); | |
18379879 | 115 | priv->rx_tfm_arc4 = NULL; |
5a656949 ZY |
116 | goto fail; |
117 | } | |
118 | ||
28eb177d JG |
119 | priv->rx_tfm_michael = crypto_alloc_hash("michael_mic", 0, |
120 | CRYPTO_ALG_ASYNC); | |
121 | if (IS_ERR(priv->rx_tfm_michael)) { | |
b453872c JG |
122 | printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate " |
123 | "crypto API michael_mic\n"); | |
18379879 | 124 | priv->rx_tfm_michael = NULL; |
b453872c JG |
125 | goto fail; |
126 | } | |
127 | ||
128 | return priv; | |
129 | ||
0edd5b44 | 130 | fail: |
b453872c | 131 | if (priv) { |
5a656949 | 132 | if (priv->tx_tfm_michael) |
28eb177d | 133 | crypto_free_hash(priv->tx_tfm_michael); |
5a656949 | 134 | if (priv->tx_tfm_arc4) |
28eb177d | 135 | crypto_free_blkcipher(priv->tx_tfm_arc4); |
5a656949 | 136 | if (priv->rx_tfm_michael) |
28eb177d | 137 | crypto_free_hash(priv->rx_tfm_michael); |
5a656949 | 138 | if (priv->rx_tfm_arc4) |
28eb177d | 139 | crypto_free_blkcipher(priv->rx_tfm_arc4); |
b453872c JG |
140 | kfree(priv); |
141 | } | |
142 | ||
143 | return NULL; | |
144 | } | |
145 | ||
b453872c JG |
146 | static void ieee80211_tkip_deinit(void *priv) |
147 | { | |
148 | struct ieee80211_tkip_data *_priv = priv; | |
5a656949 ZY |
149 | if (_priv) { |
150 | if (_priv->tx_tfm_michael) | |
28eb177d | 151 | crypto_free_hash(_priv->tx_tfm_michael); |
5a656949 | 152 | if (_priv->tx_tfm_arc4) |
28eb177d | 153 | crypto_free_blkcipher(_priv->tx_tfm_arc4); |
5a656949 | 154 | if (_priv->rx_tfm_michael) |
28eb177d | 155 | crypto_free_hash(_priv->rx_tfm_michael); |
5a656949 | 156 | if (_priv->rx_tfm_arc4) |
28eb177d | 157 | crypto_free_blkcipher(_priv->rx_tfm_arc4); |
5a656949 | 158 | } |
b453872c JG |
159 | kfree(priv); |
160 | } | |
161 | ||
b453872c JG |
162 | static inline u16 RotR1(u16 val) |
163 | { | |
164 | return (val >> 1) | (val << 15); | |
165 | } | |
166 | ||
b453872c JG |
167 | static inline u8 Lo8(u16 val) |
168 | { | |
169 | return val & 0xff; | |
170 | } | |
171 | ||
b453872c JG |
172 | static inline u8 Hi8(u16 val) |
173 | { | |
174 | return val >> 8; | |
175 | } | |
176 | ||
b453872c JG |
177 | static inline u16 Lo16(u32 val) |
178 | { | |
179 | return val & 0xffff; | |
180 | } | |
181 | ||
b453872c JG |
182 | static inline u16 Hi16(u32 val) |
183 | { | |
184 | return val >> 16; | |
185 | } | |
186 | ||
b453872c JG |
187 | static inline u16 Mk16(u8 hi, u8 lo) |
188 | { | |
189 | return lo | (((u16) hi) << 8); | |
190 | } | |
191 | ||
0edd5b44 | 192 | static inline u16 Mk16_le(u16 * v) |
b453872c JG |
193 | { |
194 | return le16_to_cpu(*v); | |
195 | } | |
196 | ||
0edd5b44 | 197 | static const u16 Sbox[256] = { |
b453872c JG |
198 | 0xC6A5, 0xF884, 0xEE99, 0xF68D, 0xFF0D, 0xD6BD, 0xDEB1, 0x9154, |
199 | 0x6050, 0x0203, 0xCEA9, 0x567D, 0xE719, 0xB562, 0x4DE6, 0xEC9A, | |
200 | 0x8F45, 0x1F9D, 0x8940, 0xFA87, 0xEF15, 0xB2EB, 0x8EC9, 0xFB0B, | |
201 | 0x41EC, 0xB367, 0x5FFD, 0x45EA, 0x23BF, 0x53F7, 0xE496, 0x9B5B, | |
202 | 0x75C2, 0xE11C, 0x3DAE, 0x4C6A, 0x6C5A, 0x7E41, 0xF502, 0x834F, | |
203 | 0x685C, 0x51F4, 0xD134, 0xF908, 0xE293, 0xAB73, 0x6253, 0x2A3F, | |
204 | 0x080C, 0x9552, 0x4665, 0x9D5E, 0x3028, 0x37A1, 0x0A0F, 0x2FB5, | |
205 | 0x0E09, 0x2436, 0x1B9B, 0xDF3D, 0xCD26, 0x4E69, 0x7FCD, 0xEA9F, | |
206 | 0x121B, 0x1D9E, 0x5874, 0x342E, 0x362D, 0xDCB2, 0xB4EE, 0x5BFB, | |
207 | 0xA4F6, 0x764D, 0xB761, 0x7DCE, 0x527B, 0xDD3E, 0x5E71, 0x1397, | |
208 | 0xA6F5, 0xB968, 0x0000, 0xC12C, 0x4060, 0xE31F, 0x79C8, 0xB6ED, | |
209 | 0xD4BE, 0x8D46, 0x67D9, 0x724B, 0x94DE, 0x98D4, 0xB0E8, 0x854A, | |
210 | 0xBB6B, 0xC52A, 0x4FE5, 0xED16, 0x86C5, 0x9AD7, 0x6655, 0x1194, | |
211 | 0x8ACF, 0xE910, 0x0406, 0xFE81, 0xA0F0, 0x7844, 0x25BA, 0x4BE3, | |
212 | 0xA2F3, 0x5DFE, 0x80C0, 0x058A, 0x3FAD, 0x21BC, 0x7048, 0xF104, | |
213 | 0x63DF, 0x77C1, 0xAF75, 0x4263, 0x2030, 0xE51A, 0xFD0E, 0xBF6D, | |
214 | 0x814C, 0x1814, 0x2635, 0xC32F, 0xBEE1, 0x35A2, 0x88CC, 0x2E39, | |
215 | 0x9357, 0x55F2, 0xFC82, 0x7A47, 0xC8AC, 0xBAE7, 0x322B, 0xE695, | |
216 | 0xC0A0, 0x1998, 0x9ED1, 0xA37F, 0x4466, 0x547E, 0x3BAB, 0x0B83, | |
217 | 0x8CCA, 0xC729, 0x6BD3, 0x283C, 0xA779, 0xBCE2, 0x161D, 0xAD76, | |
218 | 0xDB3B, 0x6456, 0x744E, 0x141E, 0x92DB, 0x0C0A, 0x486C, 0xB8E4, | |
219 | 0x9F5D, 0xBD6E, 0x43EF, 0xC4A6, 0x39A8, 0x31A4, 0xD337, 0xF28B, | |
220 | 0xD532, 0x8B43, 0x6E59, 0xDAB7, 0x018C, 0xB164, 0x9CD2, 0x49E0, | |
221 | 0xD8B4, 0xACFA, 0xF307, 0xCF25, 0xCAAF, 0xF48E, 0x47E9, 0x1018, | |
222 | 0x6FD5, 0xF088, 0x4A6F, 0x5C72, 0x3824, 0x57F1, 0x73C7, 0x9751, | |
223 | 0xCB23, 0xA17C, 0xE89C, 0x3E21, 0x96DD, 0x61DC, 0x0D86, 0x0F85, | |
224 | 0xE090, 0x7C42, 0x71C4, 0xCCAA, 0x90D8, 0x0605, 0xF701, 0x1C12, | |
225 | 0xC2A3, 0x6A5F, 0xAEF9, 0x69D0, 0x1791, 0x9958, 0x3A27, 0x27B9, | |
226 | 0xD938, 0xEB13, 0x2BB3, 0x2233, 0xD2BB, 0xA970, 0x0789, 0x33A7, | |
227 | 0x2DB6, 0x3C22, 0x1592, 0xC920, 0x8749, 0xAAFF, 0x5078, 0xA57A, | |
228 | 0x038F, 0x59F8, 0x0980, 0x1A17, 0x65DA, 0xD731, 0x84C6, 0xD0B8, | |
229 | 0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A, | |
230 | }; | |
231 | ||
b453872c JG |
232 | static inline u16 _S_(u16 v) |
233 | { | |
234 | u16 t = Sbox[Hi8(v)]; | |
235 | return Sbox[Lo8(v)] ^ ((t << 8) | (t >> 8)); | |
236 | } | |
237 | ||
b453872c JG |
238 | #define PHASE1_LOOP_COUNT 8 |
239 | ||
0edd5b44 JG |
240 | static void tkip_mixing_phase1(u16 * TTAK, const u8 * TK, const u8 * TA, |
241 | u32 IV32) | |
b453872c JG |
242 | { |
243 | int i, j; | |
244 | ||
245 | /* Initialize the 80-bit TTAK from TSC (IV32) and TA[0..5] */ | |
246 | TTAK[0] = Lo16(IV32); | |
247 | TTAK[1] = Hi16(IV32); | |
248 | TTAK[2] = Mk16(TA[1], TA[0]); | |
249 | TTAK[3] = Mk16(TA[3], TA[2]); | |
250 | TTAK[4] = Mk16(TA[5], TA[4]); | |
251 | ||
252 | for (i = 0; i < PHASE1_LOOP_COUNT; i++) { | |
253 | j = 2 * (i & 1); | |
254 | TTAK[0] += _S_(TTAK[4] ^ Mk16(TK[1 + j], TK[0 + j])); | |
255 | TTAK[1] += _S_(TTAK[0] ^ Mk16(TK[5 + j], TK[4 + j])); | |
256 | TTAK[2] += _S_(TTAK[1] ^ Mk16(TK[9 + j], TK[8 + j])); | |
257 | TTAK[3] += _S_(TTAK[2] ^ Mk16(TK[13 + j], TK[12 + j])); | |
258 | TTAK[4] += _S_(TTAK[3] ^ Mk16(TK[1 + j], TK[0 + j])) + i; | |
259 | } | |
260 | } | |
261 | ||
0edd5b44 | 262 | static void tkip_mixing_phase2(u8 * WEPSeed, const u8 * TK, const u16 * TTAK, |
b453872c JG |
263 | u16 IV16) |
264 | { | |
265 | /* Make temporary area overlap WEP seed so that the final copy can be | |
266 | * avoided on little endian hosts. */ | |
0edd5b44 | 267 | u16 *PPK = (u16 *) & WEPSeed[4]; |
b453872c JG |
268 | |
269 | /* Step 1 - make copy of TTAK and bring in TSC */ | |
270 | PPK[0] = TTAK[0]; | |
271 | PPK[1] = TTAK[1]; | |
272 | PPK[2] = TTAK[2]; | |
273 | PPK[3] = TTAK[3]; | |
274 | PPK[4] = TTAK[4]; | |
275 | PPK[5] = TTAK[4] + IV16; | |
276 | ||
277 | /* Step 2 - 96-bit bijective mixing using S-box */ | |
0edd5b44 JG |
278 | PPK[0] += _S_(PPK[5] ^ Mk16_le((u16 *) & TK[0])); |
279 | PPK[1] += _S_(PPK[0] ^ Mk16_le((u16 *) & TK[2])); | |
280 | PPK[2] += _S_(PPK[1] ^ Mk16_le((u16 *) & TK[4])); | |
281 | PPK[3] += _S_(PPK[2] ^ Mk16_le((u16 *) & TK[6])); | |
282 | PPK[4] += _S_(PPK[3] ^ Mk16_le((u16 *) & TK[8])); | |
283 | PPK[5] += _S_(PPK[4] ^ Mk16_le((u16 *) & TK[10])); | |
284 | ||
285 | PPK[0] += RotR1(PPK[5] ^ Mk16_le((u16 *) & TK[12])); | |
286 | PPK[1] += RotR1(PPK[0] ^ Mk16_le((u16 *) & TK[14])); | |
b453872c JG |
287 | PPK[2] += RotR1(PPK[1]); |
288 | PPK[3] += RotR1(PPK[2]); | |
289 | PPK[4] += RotR1(PPK[3]); | |
290 | PPK[5] += RotR1(PPK[4]); | |
291 | ||
292 | /* Step 3 - bring in last of TK bits, assign 24-bit WEP IV value | |
293 | * WEPSeed[0..2] is transmitted as WEP IV */ | |
294 | WEPSeed[0] = Hi8(IV16); | |
295 | WEPSeed[1] = (Hi8(IV16) | 0x20) & 0x7F; | |
296 | WEPSeed[2] = Lo8(IV16); | |
0edd5b44 | 297 | WEPSeed[3] = Lo8((PPK[5] ^ Mk16_le((u16 *) & TK[0])) >> 1); |
b453872c JG |
298 | |
299 | #ifdef __BIG_ENDIAN | |
300 | { | |
301 | int i; | |
302 | for (i = 0; i < 6; i++) | |
303 | PPK[i] = (PPK[i] << 8) | (PPK[i] >> 8); | |
304 | } | |
305 | #endif | |
306 | } | |
307 | ||
9184d934 ZY |
308 | static int ieee80211_tkip_hdr(struct sk_buff *skb, int hdr_len, |
309 | u8 * rc4key, int keylen, void *priv) | |
b453872c JG |
310 | { |
311 | struct ieee80211_tkip_data *tkey = priv; | |
312 | int len; | |
9184d934 | 313 | u8 *pos; |
ee34af37 | 314 | struct ieee80211_hdr_4addr *hdr; |
b453872c | 315 | |
ee34af37 | 316 | hdr = (struct ieee80211_hdr_4addr *)skb->data; |
20d64713 | 317 | |
31b59eae | 318 | if (skb_headroom(skb) < 8 || skb->len < hdr_len) |
9184d934 ZY |
319 | return -1; |
320 | ||
321 | if (rc4key == NULL || keylen < 16) | |
322 | return -1; | |
b453872c | 323 | |
b453872c JG |
324 | if (!tkey->tx_phase1_done) { |
325 | tkip_mixing_phase1(tkey->tx_ttak, tkey->key, hdr->addr2, | |
326 | tkey->tx_iv32); | |
327 | tkey->tx_phase1_done = 1; | |
328 | } | |
329 | tkip_mixing_phase2(rc4key, tkey->key, tkey->tx_ttak, tkey->tx_iv16); | |
330 | ||
331 | len = skb->len - hdr_len; | |
332 | pos = skb_push(skb, 8); | |
333 | memmove(pos, pos + 8, hdr_len); | |
334 | pos += hdr_len; | |
b453872c | 335 | |
31b59eae JK |
336 | *pos++ = *rc4key; |
337 | *pos++ = *(rc4key + 1); | |
338 | *pos++ = *(rc4key + 2); | |
0edd5b44 | 339 | *pos++ = (tkey->key_idx << 6) | (1 << 5) /* Ext IV included */ ; |
b453872c JG |
340 | *pos++ = tkey->tx_iv32 & 0xff; |
341 | *pos++ = (tkey->tx_iv32 >> 8) & 0xff; | |
342 | *pos++ = (tkey->tx_iv32 >> 16) & 0xff; | |
343 | *pos++ = (tkey->tx_iv32 >> 24) & 0xff; | |
344 | ||
9184d934 ZY |
345 | tkey->tx_iv16++; |
346 | if (tkey->tx_iv16 == 0) { | |
347 | tkey->tx_phase1_done = 0; | |
348 | tkey->tx_iv32++; | |
349 | } | |
b453872c | 350 | |
9184d934 | 351 | return 8; |
31b59eae JK |
352 | } |
353 | ||
354 | static int ieee80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv) | |
355 | { | |
356 | struct ieee80211_tkip_data *tkey = priv; | |
28eb177d | 357 | struct blkcipher_desc desc = { .tfm = tkey->tx_tfm_arc4 }; |
31b59eae | 358 | int len; |
9184d934 ZY |
359 | u8 rc4key[16], *pos, *icv; |
360 | u32 crc; | |
31b59eae JK |
361 | struct scatterlist sg; |
362 | ||
6eb6edf0 | 363 | if (tkey->flags & IEEE80211_CRYPTO_TKIP_COUNTERMEASURES) { |
31b59eae JK |
364 | if (net_ratelimit()) { |
365 | struct ieee80211_hdr_4addr *hdr = | |
366 | (struct ieee80211_hdr_4addr *)skb->data; | |
9184d934 | 367 | printk(KERN_DEBUG ": TKIP countermeasures: dropped " |
31b59eae | 368 | "TX packet to " MAC_FMT "\n", |
6eb6edf0 | 369 | MAC_ARG(hdr->addr1)); |
31b59eae JK |
370 | } |
371 | return -1; | |
372 | } | |
373 | ||
374 | if (skb_tailroom(skb) < 4 || skb->len < hdr_len) | |
375 | return -1; | |
376 | ||
377 | len = skb->len - hdr_len; | |
378 | pos = skb->data + hdr_len; | |
379 | ||
9184d934 | 380 | if ((ieee80211_tkip_hdr(skb, hdr_len, rc4key, 16, priv)) < 0) |
31b59eae JK |
381 | return -1; |
382 | ||
9184d934 ZY |
383 | icv = skb_put(skb, 4); |
384 | ||
385 | crc = ~crc32_le(~0, pos, len); | |
386 | icv[0] = crc; | |
387 | icv[1] = crc >> 8; | |
388 | icv[2] = crc >> 16; | |
389 | icv[3] = crc >> 24; | |
390 | ||
28eb177d | 391 | crypto_blkcipher_setkey(tkey->tx_tfm_arc4, rc4key, 16); |
b453872c JG |
392 | sg.page = virt_to_page(pos); |
393 | sg.offset = offset_in_page(pos); | |
394 | sg.length = len + 4; | |
f12cc209 | 395 | return crypto_blkcipher_encrypt(&desc, &sg, &sg, len + 4); |
b4328d87 ZY |
396 | } |
397 | ||
18379879 JG |
398 | /* |
399 | * deal with seq counter wrapping correctly. | |
400 | * refer to timer_after() for jiffies wrapping handling | |
401 | */ | |
402 | static inline int tkip_replay_check(u32 iv32_n, u16 iv16_n, | |
403 | u32 iv32_o, u16 iv16_o) | |
404 | { | |
405 | if ((s32)iv32_n - (s32)iv32_o < 0 || | |
406 | (iv32_n == iv32_o && iv16_n <= iv16_o)) | |
407 | return 1; | |
408 | return 0; | |
409 | } | |
410 | ||
b453872c JG |
411 | static int ieee80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv) |
412 | { | |
413 | struct ieee80211_tkip_data *tkey = priv; | |
28eb177d | 414 | struct blkcipher_desc desc = { .tfm = tkey->rx_tfm_arc4 }; |
b453872c JG |
415 | u8 rc4key[16]; |
416 | u8 keyidx, *pos; | |
417 | u32 iv32; | |
418 | u16 iv16; | |
ee34af37 | 419 | struct ieee80211_hdr_4addr *hdr; |
b453872c JG |
420 | u8 icv[4]; |
421 | u32 crc; | |
422 | struct scatterlist sg; | |
423 | int plen; | |
424 | ||
ee34af37 | 425 | hdr = (struct ieee80211_hdr_4addr *)skb->data; |
20d64713 | 426 | |
6eb6edf0 | 427 | if (tkey->flags & IEEE80211_CRYPTO_TKIP_COUNTERMEASURES) { |
20d64713 | 428 | if (net_ratelimit()) { |
9184d934 | 429 | printk(KERN_DEBUG ": TKIP countermeasures: dropped " |
20d64713 | 430 | "received packet from " MAC_FMT "\n", |
6eb6edf0 | 431 | MAC_ARG(hdr->addr2)); |
20d64713 JK |
432 | } |
433 | return -1; | |
434 | } | |
435 | ||
b453872c JG |
436 | if (skb->len < hdr_len + 8 + 4) |
437 | return -1; | |
438 | ||
b453872c JG |
439 | pos = skb->data + hdr_len; |
440 | keyidx = pos[3]; | |
441 | if (!(keyidx & (1 << 5))) { | |
442 | if (net_ratelimit()) { | |
443 | printk(KERN_DEBUG "TKIP: received packet without ExtIV" | |
444 | " flag from " MAC_FMT "\n", MAC_ARG(hdr->addr2)); | |
445 | } | |
446 | return -2; | |
447 | } | |
448 | keyidx >>= 6; | |
449 | if (tkey->key_idx != keyidx) { | |
450 | printk(KERN_DEBUG "TKIP: RX tkey->key_idx=%d frame " | |
451 | "keyidx=%d priv=%p\n", tkey->key_idx, keyidx, priv); | |
452 | return -6; | |
453 | } | |
454 | if (!tkey->key_set) { | |
455 | if (net_ratelimit()) { | |
456 | printk(KERN_DEBUG "TKIP: received packet from " MAC_FMT | |
457 | " with keyid=%d that does not have a configured" | |
458 | " key\n", MAC_ARG(hdr->addr2), keyidx); | |
459 | } | |
460 | return -3; | |
461 | } | |
462 | iv16 = (pos[0] << 8) | pos[2]; | |
463 | iv32 = pos[4] | (pos[5] << 8) | (pos[6] << 16) | (pos[7] << 24); | |
464 | pos += 8; | |
465 | ||
b4328d87 | 466 | if (tkip_replay_check(iv32, iv16, tkey->rx_iv32, tkey->rx_iv16)) { |
b453872c | 467 | if (net_ratelimit()) { |
aeb998c1 | 468 | IEEE80211_DEBUG_DROP("TKIP: replay detected: STA=" MAC_FMT |
b453872c JG |
469 | " previous TSC %08x%04x received TSC " |
470 | "%08x%04x\n", MAC_ARG(hdr->addr2), | |
471 | tkey->rx_iv32, tkey->rx_iv16, iv32, iv16); | |
472 | } | |
473 | tkey->dot11RSNAStatsTKIPReplays++; | |
474 | return -4; | |
475 | } | |
476 | ||
477 | if (iv32 != tkey->rx_iv32 || !tkey->rx_phase1_done) { | |
478 | tkip_mixing_phase1(tkey->rx_ttak, tkey->key, hdr->addr2, iv32); | |
479 | tkey->rx_phase1_done = 1; | |
480 | } | |
481 | tkip_mixing_phase2(rc4key, tkey->key, tkey->rx_ttak, iv16); | |
482 | ||
483 | plen = skb->len - hdr_len - 12; | |
484 | ||
28eb177d | 485 | crypto_blkcipher_setkey(tkey->rx_tfm_arc4, rc4key, 16); |
b453872c JG |
486 | sg.page = virt_to_page(pos); |
487 | sg.offset = offset_in_page(pos); | |
488 | sg.length = plen + 4; | |
f12cc209 HX |
489 | if (crypto_blkcipher_decrypt(&desc, &sg, &sg, plen + 4)) { |
490 | if (net_ratelimit()) { | |
491 | printk(KERN_DEBUG ": TKIP: failed to decrypt " | |
492 | "received packet from " MAC_FMT "\n", | |
493 | MAC_ARG(hdr->addr2)); | |
494 | } | |
495 | return -7; | |
496 | } | |
b453872c JG |
497 | |
498 | crc = ~crc32_le(~0, pos, plen); | |
499 | icv[0] = crc; | |
500 | icv[1] = crc >> 8; | |
501 | icv[2] = crc >> 16; | |
502 | icv[3] = crc >> 24; | |
503 | if (memcmp(icv, pos + plen, 4) != 0) { | |
504 | if (iv32 != tkey->rx_iv32) { | |
505 | /* Previously cached Phase1 result was already lost, so | |
506 | * it needs to be recalculated for the next packet. */ | |
507 | tkey->rx_phase1_done = 0; | |
508 | } | |
509 | if (net_ratelimit()) { | |
aeb998c1 | 510 | IEEE80211_DEBUG_DROP("TKIP: ICV error detected: STA=" |
b453872c JG |
511 | MAC_FMT "\n", MAC_ARG(hdr->addr2)); |
512 | } | |
513 | tkey->dot11RSNAStatsTKIPICVErrors++; | |
514 | return -5; | |
515 | } | |
516 | ||
517 | /* Update real counters only after Michael MIC verification has | |
518 | * completed */ | |
519 | tkey->rx_iv32_new = iv32; | |
520 | tkey->rx_iv16_new = iv16; | |
521 | ||
522 | /* Remove IV and ICV */ | |
523 | memmove(skb->data + 8, skb->data, hdr_len); | |
524 | skb_pull(skb, 8); | |
525 | skb_trim(skb, skb->len - 4); | |
526 | ||
527 | return keyidx; | |
528 | } | |
529 | ||
28eb177d | 530 | static int michael_mic(struct crypto_hash *tfm_michael, u8 * key, u8 * hdr, |
0edd5b44 | 531 | u8 * data, size_t data_len, u8 * mic) |
b453872c | 532 | { |
35058687 | 533 | struct hash_desc desc; |
b453872c JG |
534 | struct scatterlist sg[2]; |
535 | ||
5a656949 | 536 | if (tfm_michael == NULL) { |
b453872c JG |
537 | printk(KERN_WARNING "michael_mic: tfm_michael == NULL\n"); |
538 | return -1; | |
539 | } | |
540 | sg[0].page = virt_to_page(hdr); | |
541 | sg[0].offset = offset_in_page(hdr); | |
542 | sg[0].length = 16; | |
543 | ||
544 | sg[1].page = virt_to_page(data); | |
545 | sg[1].offset = offset_in_page(data); | |
546 | sg[1].length = data_len; | |
547 | ||
28eb177d | 548 | if (crypto_hash_setkey(tfm_michael, key, 8)) |
35058687 | 549 | return -1; |
b453872c | 550 | |
28eb177d | 551 | desc.tfm = tfm_michael; |
35058687 HX |
552 | desc.flags = 0; |
553 | return crypto_hash_digest(&desc, sg, data_len + 16, mic); | |
b453872c JG |
554 | } |
555 | ||
0edd5b44 | 556 | static void michael_mic_hdr(struct sk_buff *skb, u8 * hdr) |
b453872c | 557 | { |
ee34af37 | 558 | struct ieee80211_hdr_4addr *hdr11; |
ea284152 | 559 | u16 stype; |
b453872c | 560 | |
ee34af37 | 561 | hdr11 = (struct ieee80211_hdr_4addr *)skb->data; |
ea284152 ZY |
562 | stype = WLAN_FC_GET_STYPE(le16_to_cpu(hdr11->frame_ctl)); |
563 | ||
b453872c JG |
564 | switch (le16_to_cpu(hdr11->frame_ctl) & |
565 | (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) { | |
566 | case IEEE80211_FCTL_TODS: | |
0edd5b44 JG |
567 | memcpy(hdr, hdr11->addr3, ETH_ALEN); /* DA */ |
568 | memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN); /* SA */ | |
b453872c JG |
569 | break; |
570 | case IEEE80211_FCTL_FROMDS: | |
0edd5b44 JG |
571 | memcpy(hdr, hdr11->addr1, ETH_ALEN); /* DA */ |
572 | memcpy(hdr + ETH_ALEN, hdr11->addr3, ETH_ALEN); /* SA */ | |
b453872c JG |
573 | break; |
574 | case IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS: | |
0edd5b44 JG |
575 | memcpy(hdr, hdr11->addr3, ETH_ALEN); /* DA */ |
576 | memcpy(hdr + ETH_ALEN, hdr11->addr4, ETH_ALEN); /* SA */ | |
b453872c JG |
577 | break; |
578 | case 0: | |
0edd5b44 JG |
579 | memcpy(hdr, hdr11->addr1, ETH_ALEN); /* DA */ |
580 | memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN); /* SA */ | |
b453872c JG |
581 | break; |
582 | } | |
583 | ||
ea284152 ZY |
584 | if (stype & IEEE80211_STYPE_QOS_DATA) { |
585 | const struct ieee80211_hdr_3addrqos *qoshdr = | |
586 | (struct ieee80211_hdr_3addrqos *)skb->data; | |
65b6a277 | 587 | hdr[12] = qoshdr->qos_ctl & cpu_to_le16(IEEE80211_QCTL_TID); |
ea284152 ZY |
588 | } else |
589 | hdr[12] = 0; /* priority */ | |
590 | ||
0edd5b44 | 591 | hdr[13] = hdr[14] = hdr[15] = 0; /* reserved */ |
b453872c JG |
592 | } |
593 | ||
0edd5b44 JG |
594 | static int ieee80211_michael_mic_add(struct sk_buff *skb, int hdr_len, |
595 | void *priv) | |
b453872c JG |
596 | { |
597 | struct ieee80211_tkip_data *tkey = priv; | |
598 | u8 *pos; | |
599 | ||
600 | if (skb_tailroom(skb) < 8 || skb->len < hdr_len) { | |
601 | printk(KERN_DEBUG "Invalid packet for Michael MIC add " | |
602 | "(tailroom=%d hdr_len=%d skb->len=%d)\n", | |
603 | skb_tailroom(skb), hdr_len, skb->len); | |
604 | return -1; | |
605 | } | |
606 | ||
607 | michael_mic_hdr(skb, tkey->tx_hdr); | |
608 | pos = skb_put(skb, 8); | |
5a656949 | 609 | if (michael_mic(tkey->tx_tfm_michael, &tkey->key[16], tkey->tx_hdr, |
b453872c JG |
610 | skb->data + hdr_len, skb->len - 8 - hdr_len, pos)) |
611 | return -1; | |
612 | ||
613 | return 0; | |
614 | } | |
615 | ||
b453872c | 616 | static void ieee80211_michael_mic_failure(struct net_device *dev, |
ee34af37 JK |
617 | struct ieee80211_hdr_4addr *hdr, |
618 | int keyidx) | |
b453872c JG |
619 | { |
620 | union iwreq_data wrqu; | |
621 | struct iw_michaelmicfailure ev; | |
622 | ||
623 | /* TODO: needed parameters: count, keyid, key type, TSC */ | |
624 | memset(&ev, 0, sizeof(ev)); | |
625 | ev.flags = keyidx & IW_MICFAILURE_KEY_ID; | |
626 | if (hdr->addr1[0] & 0x01) | |
627 | ev.flags |= IW_MICFAILURE_GROUP; | |
628 | else | |
629 | ev.flags |= IW_MICFAILURE_PAIRWISE; | |
630 | ev.src_addr.sa_family = ARPHRD_ETHER; | |
631 | memcpy(ev.src_addr.sa_data, hdr->addr2, ETH_ALEN); | |
632 | memset(&wrqu, 0, sizeof(wrqu)); | |
633 | wrqu.data.length = sizeof(ev); | |
0edd5b44 | 634 | wireless_send_event(dev, IWEVMICHAELMICFAILURE, &wrqu, (char *)&ev); |
b453872c | 635 | } |
b453872c JG |
636 | |
637 | static int ieee80211_michael_mic_verify(struct sk_buff *skb, int keyidx, | |
0edd5b44 | 638 | int hdr_len, void *priv) |
b453872c JG |
639 | { |
640 | struct ieee80211_tkip_data *tkey = priv; | |
641 | u8 mic[8]; | |
642 | ||
643 | if (!tkey->key_set) | |
644 | return -1; | |
645 | ||
646 | michael_mic_hdr(skb, tkey->rx_hdr); | |
5a656949 | 647 | if (michael_mic(tkey->rx_tfm_michael, &tkey->key[24], tkey->rx_hdr, |
b453872c JG |
648 | skb->data + hdr_len, skb->len - 8 - hdr_len, mic)) |
649 | return -1; | |
650 | if (memcmp(mic, skb->data + skb->len - 8, 8) != 0) { | |
ee34af37 JK |
651 | struct ieee80211_hdr_4addr *hdr; |
652 | hdr = (struct ieee80211_hdr_4addr *)skb->data; | |
b453872c JG |
653 | printk(KERN_DEBUG "%s: Michael MIC verification failed for " |
654 | "MSDU from " MAC_FMT " keyidx=%d\n", | |
655 | skb->dev ? skb->dev->name : "N/A", MAC_ARG(hdr->addr2), | |
656 | keyidx); | |
657 | if (skb->dev) | |
658 | ieee80211_michael_mic_failure(skb->dev, hdr, keyidx); | |
659 | tkey->dot11RSNAStatsTKIPLocalMICFailures++; | |
660 | return -1; | |
661 | } | |
662 | ||
663 | /* Update TSC counters for RX now that the packet verification has | |
664 | * completed. */ | |
665 | tkey->rx_iv32 = tkey->rx_iv32_new; | |
666 | tkey->rx_iv16 = tkey->rx_iv16_new; | |
667 | ||
668 | skb_trim(skb, skb->len - 8); | |
669 | ||
670 | return 0; | |
671 | } | |
672 | ||
0edd5b44 | 673 | static int ieee80211_tkip_set_key(void *key, int len, u8 * seq, void *priv) |
b453872c JG |
674 | { |
675 | struct ieee80211_tkip_data *tkey = priv; | |
676 | int keyidx; | |
28eb177d JG |
677 | struct crypto_hash *tfm = tkey->tx_tfm_michael; |
678 | struct crypto_blkcipher *tfm2 = tkey->tx_tfm_arc4; | |
679 | struct crypto_hash *tfm3 = tkey->rx_tfm_michael; | |
680 | struct crypto_blkcipher *tfm4 = tkey->rx_tfm_arc4; | |
b453872c JG |
681 | |
682 | keyidx = tkey->key_idx; | |
683 | memset(tkey, 0, sizeof(*tkey)); | |
684 | tkey->key_idx = keyidx; | |
5a656949 ZY |
685 | tkey->tx_tfm_michael = tfm; |
686 | tkey->tx_tfm_arc4 = tfm2; | |
687 | tkey->rx_tfm_michael = tfm3; | |
688 | tkey->rx_tfm_arc4 = tfm4; | |
b453872c JG |
689 | if (len == TKIP_KEY_LEN) { |
690 | memcpy(tkey->key, key, TKIP_KEY_LEN); | |
691 | tkey->key_set = 1; | |
0edd5b44 | 692 | tkey->tx_iv16 = 1; /* TSC is initialized to 1 */ |
b453872c JG |
693 | if (seq) { |
694 | tkey->rx_iv32 = (seq[5] << 24) | (seq[4] << 16) | | |
0edd5b44 | 695 | (seq[3] << 8) | seq[2]; |
b453872c JG |
696 | tkey->rx_iv16 = (seq[1] << 8) | seq[0]; |
697 | } | |
698 | } else if (len == 0) | |
699 | tkey->key_set = 0; | |
700 | else | |
701 | return -1; | |
702 | ||
703 | return 0; | |
704 | } | |
705 | ||
0edd5b44 | 706 | static int ieee80211_tkip_get_key(void *key, int len, u8 * seq, void *priv) |
b453872c JG |
707 | { |
708 | struct ieee80211_tkip_data *tkey = priv; | |
709 | ||
710 | if (len < TKIP_KEY_LEN) | |
711 | return -1; | |
712 | ||
713 | if (!tkey->key_set) | |
714 | return 0; | |
715 | memcpy(key, tkey->key, TKIP_KEY_LEN); | |
716 | ||
717 | if (seq) { | |
718 | /* Return the sequence number of the last transmitted frame. */ | |
719 | u16 iv16 = tkey->tx_iv16; | |
720 | u32 iv32 = tkey->tx_iv32; | |
721 | if (iv16 == 0) | |
722 | iv32--; | |
723 | iv16--; | |
724 | seq[0] = tkey->tx_iv16; | |
725 | seq[1] = tkey->tx_iv16 >> 8; | |
726 | seq[2] = tkey->tx_iv32; | |
727 | seq[3] = tkey->tx_iv32 >> 8; | |
728 | seq[4] = tkey->tx_iv32 >> 16; | |
729 | seq[5] = tkey->tx_iv32 >> 24; | |
730 | } | |
731 | ||
732 | return TKIP_KEY_LEN; | |
733 | } | |
734 | ||
0edd5b44 | 735 | static char *ieee80211_tkip_print_stats(char *p, void *priv) |
b453872c JG |
736 | { |
737 | struct ieee80211_tkip_data *tkip = priv; | |
738 | p += sprintf(p, "key[%d] alg=TKIP key_set=%d " | |
739 | "tx_pn=%02x%02x%02x%02x%02x%02x " | |
740 | "rx_pn=%02x%02x%02x%02x%02x%02x " | |
741 | "replays=%d icv_errors=%d local_mic_failures=%d\n", | |
742 | tkip->key_idx, tkip->key_set, | |
743 | (tkip->tx_iv32 >> 24) & 0xff, | |
744 | (tkip->tx_iv32 >> 16) & 0xff, | |
745 | (tkip->tx_iv32 >> 8) & 0xff, | |
746 | tkip->tx_iv32 & 0xff, | |
747 | (tkip->tx_iv16 >> 8) & 0xff, | |
748 | tkip->tx_iv16 & 0xff, | |
749 | (tkip->rx_iv32 >> 24) & 0xff, | |
750 | (tkip->rx_iv32 >> 16) & 0xff, | |
751 | (tkip->rx_iv32 >> 8) & 0xff, | |
752 | tkip->rx_iv32 & 0xff, | |
753 | (tkip->rx_iv16 >> 8) & 0xff, | |
754 | tkip->rx_iv16 & 0xff, | |
755 | tkip->dot11RSNAStatsTKIPReplays, | |
756 | tkip->dot11RSNAStatsTKIPICVErrors, | |
757 | tkip->dot11RSNAStatsTKIPLocalMICFailures); | |
758 | return p; | |
759 | } | |
760 | ||
b453872c | 761 | static struct ieee80211_crypto_ops ieee80211_crypt_tkip = { |
74079fdc JK |
762 | .name = "TKIP", |
763 | .init = ieee80211_tkip_init, | |
764 | .deinit = ieee80211_tkip_deinit, | |
9184d934 | 765 | .build_iv = ieee80211_tkip_hdr, |
74079fdc JK |
766 | .encrypt_mpdu = ieee80211_tkip_encrypt, |
767 | .decrypt_mpdu = ieee80211_tkip_decrypt, | |
768 | .encrypt_msdu = ieee80211_michael_mic_add, | |
769 | .decrypt_msdu = ieee80211_michael_mic_verify, | |
770 | .set_key = ieee80211_tkip_set_key, | |
771 | .get_key = ieee80211_tkip_get_key, | |
772 | .print_stats = ieee80211_tkip_print_stats, | |
1264fc04 JK |
773 | .extra_mpdu_prefix_len = 4 + 4, /* IV + ExtIV */ |
774 | .extra_mpdu_postfix_len = 4, /* ICV */ | |
775 | .extra_msdu_postfix_len = 8, /* MIC */ | |
6eb6edf0 JK |
776 | .get_flags = ieee80211_tkip_get_flags, |
777 | .set_flags = ieee80211_tkip_set_flags, | |
74079fdc | 778 | .owner = THIS_MODULE, |
b453872c JG |
779 | }; |
780 | ||
b453872c JG |
781 | static int __init ieee80211_crypto_tkip_init(void) |
782 | { | |
783 | return ieee80211_register_crypto_ops(&ieee80211_crypt_tkip); | |
784 | } | |
785 | ||
b453872c JG |
786 | static void __exit ieee80211_crypto_tkip_exit(void) |
787 | { | |
788 | ieee80211_unregister_crypto_ops(&ieee80211_crypt_tkip); | |
789 | } | |
790 | ||
b453872c JG |
791 | module_init(ieee80211_crypto_tkip_init); |
792 | module_exit(ieee80211_crypto_tkip_exit); |