Commit | Line | Data |
---|---|---|
b453872c | 1 | /* |
274bfb8d | 2 | * lib80211 crypt: host-based TKIP encryption implementation for lib80211 |
b453872c | 3 | * |
85d32e7b | 4 | * Copyright (c) 2003-2004, Jouni Malinen <j@w1.fi> |
274bfb8d | 5 | * Copyright (c) 2008, John W. Linville <linville@tuxdriver.com> |
b453872c JG |
6 | * |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. See README and COPYING for | |
10 | * more details. | |
11 | */ | |
12 | ||
e9c0268f JP |
13 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
14 | ||
f12cc209 | 15 | #include <linux/err.h> |
b453872c JG |
16 | #include <linux/module.h> |
17 | #include <linux/init.h> | |
18 | #include <linux/slab.h> | |
19 | #include <linux/random.h> | |
11763609 | 20 | #include <linux/scatterlist.h> |
b453872c JG |
21 | #include <linux/skbuff.h> |
22 | #include <linux/netdevice.h> | |
d7fe0f24 | 23 | #include <linux/mm.h> |
b453872c JG |
24 | #include <linux/if_ether.h> |
25 | #include <linux/if_arp.h> | |
26 | #include <asm/string.h> | |
27 | ||
274bfb8d JL |
28 | #include <linux/wireless.h> |
29 | #include <linux/ieee80211.h> | |
30 | #include <net/iw_handler.h> | |
b453872c | 31 | |
608fb34c HX |
32 | #include <crypto/hash.h> |
33 | #include <crypto/skcipher.h> | |
b453872c JG |
34 | #include <linux/crc32.h> |
35 | ||
274bfb8d JL |
36 | #include <net/lib80211.h> |
37 | ||
b453872c | 38 | MODULE_AUTHOR("Jouni Malinen"); |
274bfb8d | 39 | MODULE_DESCRIPTION("lib80211 crypt: TKIP"); |
b453872c JG |
40 | MODULE_LICENSE("GPL"); |
41 | ||
299af9d3 AT |
42 | #define TKIP_HDR_LEN 8 |
43 | ||
274bfb8d | 44 | struct lib80211_tkip_data { |
b453872c JG |
45 | #define TKIP_KEY_LEN 32 |
46 | u8 key[TKIP_KEY_LEN]; | |
47 | int key_set; | |
48 | ||
49 | u32 tx_iv32; | |
50 | u16 tx_iv16; | |
51 | u16 tx_ttak[5]; | |
52 | int tx_phase1_done; | |
53 | ||
54 | u32 rx_iv32; | |
55 | u16 rx_iv16; | |
56 | u16 rx_ttak[5]; | |
57 | int rx_phase1_done; | |
58 | u32 rx_iv32_new; | |
59 | u16 rx_iv16_new; | |
60 | ||
61 | u32 dot11RSNAStatsTKIPReplays; | |
62 | u32 dot11RSNAStatsTKIPICVErrors; | |
63 | u32 dot11RSNAStatsTKIPLocalMICFailures; | |
64 | ||
65 | int key_idx; | |
66 | ||
608fb34c HX |
67 | struct crypto_skcipher *rx_tfm_arc4; |
68 | struct crypto_ahash *rx_tfm_michael; | |
69 | struct crypto_skcipher *tx_tfm_arc4; | |
70 | struct crypto_ahash *tx_tfm_michael; | |
b453872c JG |
71 | |
72 | /* scratch buffers for virt_to_page() (crypto API) */ | |
73 | u8 rx_hdr[16], tx_hdr[16]; | |
20d64713 | 74 | |
6eb6edf0 | 75 | unsigned long flags; |
b453872c JG |
76 | }; |
77 | ||
274bfb8d | 78 | static unsigned long lib80211_tkip_set_flags(unsigned long flags, void *priv) |
6eb6edf0 | 79 | { |
274bfb8d | 80 | struct lib80211_tkip_data *_priv = priv; |
6eb6edf0 JK |
81 | unsigned long old_flags = _priv->flags; |
82 | _priv->flags = flags; | |
83 | return old_flags; | |
84 | } | |
85 | ||
274bfb8d | 86 | static unsigned long lib80211_tkip_get_flags(void *priv) |
6eb6edf0 | 87 | { |
274bfb8d | 88 | struct lib80211_tkip_data *_priv = priv; |
6eb6edf0 JK |
89 | return _priv->flags; |
90 | } | |
91 | ||
274bfb8d | 92 | static void *lib80211_tkip_init(int key_idx) |
b453872c | 93 | { |
274bfb8d | 94 | struct lib80211_tkip_data *priv; |
b453872c | 95 | |
8aa914b7 | 96 | priv = kzalloc(sizeof(*priv), GFP_ATOMIC); |
b453872c JG |
97 | if (priv == NULL) |
98 | goto fail; | |
20d64713 | 99 | |
b453872c JG |
100 | priv->key_idx = key_idx; |
101 | ||
608fb34c HX |
102 | priv->tx_tfm_arc4 = crypto_alloc_skcipher("ecb(arc4)", 0, |
103 | CRYPTO_ALG_ASYNC); | |
28eb177d | 104 | if (IS_ERR(priv->tx_tfm_arc4)) { |
18379879 | 105 | priv->tx_tfm_arc4 = NULL; |
b453872c JG |
106 | goto fail; |
107 | } | |
108 | ||
608fb34c HX |
109 | priv->tx_tfm_michael = crypto_alloc_ahash("michael_mic", 0, |
110 | CRYPTO_ALG_ASYNC); | |
28eb177d | 111 | if (IS_ERR(priv->tx_tfm_michael)) { |
18379879 | 112 | priv->tx_tfm_michael = NULL; |
5a656949 ZY |
113 | goto fail; |
114 | } | |
115 | ||
608fb34c HX |
116 | priv->rx_tfm_arc4 = crypto_alloc_skcipher("ecb(arc4)", 0, |
117 | CRYPTO_ALG_ASYNC); | |
28eb177d | 118 | if (IS_ERR(priv->rx_tfm_arc4)) { |
18379879 | 119 | priv->rx_tfm_arc4 = NULL; |
5a656949 ZY |
120 | goto fail; |
121 | } | |
122 | ||
608fb34c HX |
123 | priv->rx_tfm_michael = crypto_alloc_ahash("michael_mic", 0, |
124 | CRYPTO_ALG_ASYNC); | |
28eb177d | 125 | if (IS_ERR(priv->rx_tfm_michael)) { |
18379879 | 126 | priv->rx_tfm_michael = NULL; |
b453872c JG |
127 | goto fail; |
128 | } | |
129 | ||
130 | return priv; | |
131 | ||
0edd5b44 | 132 | fail: |
b453872c | 133 | if (priv) { |
608fb34c HX |
134 | crypto_free_ahash(priv->tx_tfm_michael); |
135 | crypto_free_skcipher(priv->tx_tfm_arc4); | |
136 | crypto_free_ahash(priv->rx_tfm_michael); | |
137 | crypto_free_skcipher(priv->rx_tfm_arc4); | |
b453872c JG |
138 | kfree(priv); |
139 | } | |
140 | ||
141 | return NULL; | |
142 | } | |
143 | ||
274bfb8d | 144 | static void lib80211_tkip_deinit(void *priv) |
b453872c | 145 | { |
274bfb8d | 146 | struct lib80211_tkip_data *_priv = priv; |
5a656949 | 147 | if (_priv) { |
608fb34c HX |
148 | crypto_free_ahash(_priv->tx_tfm_michael); |
149 | crypto_free_skcipher(_priv->tx_tfm_arc4); | |
150 | crypto_free_ahash(_priv->rx_tfm_michael); | |
151 | crypto_free_skcipher(_priv->rx_tfm_arc4); | |
5a656949 | 152 | } |
b453872c JG |
153 | kfree(priv); |
154 | } | |
155 | ||
b453872c JG |
156 | static inline u16 RotR1(u16 val) |
157 | { | |
158 | return (val >> 1) | (val << 15); | |
159 | } | |
160 | ||
b453872c JG |
161 | static inline u8 Lo8(u16 val) |
162 | { | |
163 | return val & 0xff; | |
164 | } | |
165 | ||
b453872c JG |
166 | static inline u8 Hi8(u16 val) |
167 | { | |
168 | return val >> 8; | |
169 | } | |
170 | ||
b453872c JG |
171 | static inline u16 Lo16(u32 val) |
172 | { | |
173 | return val & 0xffff; | |
174 | } | |
175 | ||
b453872c JG |
176 | static inline u16 Hi16(u32 val) |
177 | { | |
178 | return val >> 16; | |
179 | } | |
180 | ||
b453872c JG |
181 | static inline u16 Mk16(u8 hi, u8 lo) |
182 | { | |
183 | return lo | (((u16) hi) << 8); | |
184 | } | |
185 | ||
d9e94d56 | 186 | static inline u16 Mk16_le(__le16 * v) |
b453872c JG |
187 | { |
188 | return le16_to_cpu(*v); | |
189 | } | |
190 | ||
0edd5b44 | 191 | static const u16 Sbox[256] = { |
b453872c JG |
192 | 0xC6A5, 0xF884, 0xEE99, 0xF68D, 0xFF0D, 0xD6BD, 0xDEB1, 0x9154, |
193 | 0x6050, 0x0203, 0xCEA9, 0x567D, 0xE719, 0xB562, 0x4DE6, 0xEC9A, | |
194 | 0x8F45, 0x1F9D, 0x8940, 0xFA87, 0xEF15, 0xB2EB, 0x8EC9, 0xFB0B, | |
195 | 0x41EC, 0xB367, 0x5FFD, 0x45EA, 0x23BF, 0x53F7, 0xE496, 0x9B5B, | |
196 | 0x75C2, 0xE11C, 0x3DAE, 0x4C6A, 0x6C5A, 0x7E41, 0xF502, 0x834F, | |
197 | 0x685C, 0x51F4, 0xD134, 0xF908, 0xE293, 0xAB73, 0x6253, 0x2A3F, | |
198 | 0x080C, 0x9552, 0x4665, 0x9D5E, 0x3028, 0x37A1, 0x0A0F, 0x2FB5, | |
199 | 0x0E09, 0x2436, 0x1B9B, 0xDF3D, 0xCD26, 0x4E69, 0x7FCD, 0xEA9F, | |
200 | 0x121B, 0x1D9E, 0x5874, 0x342E, 0x362D, 0xDCB2, 0xB4EE, 0x5BFB, | |
201 | 0xA4F6, 0x764D, 0xB761, 0x7DCE, 0x527B, 0xDD3E, 0x5E71, 0x1397, | |
202 | 0xA6F5, 0xB968, 0x0000, 0xC12C, 0x4060, 0xE31F, 0x79C8, 0xB6ED, | |
203 | 0xD4BE, 0x8D46, 0x67D9, 0x724B, 0x94DE, 0x98D4, 0xB0E8, 0x854A, | |
204 | 0xBB6B, 0xC52A, 0x4FE5, 0xED16, 0x86C5, 0x9AD7, 0x6655, 0x1194, | |
205 | 0x8ACF, 0xE910, 0x0406, 0xFE81, 0xA0F0, 0x7844, 0x25BA, 0x4BE3, | |
206 | 0xA2F3, 0x5DFE, 0x80C0, 0x058A, 0x3FAD, 0x21BC, 0x7048, 0xF104, | |
207 | 0x63DF, 0x77C1, 0xAF75, 0x4263, 0x2030, 0xE51A, 0xFD0E, 0xBF6D, | |
208 | 0x814C, 0x1814, 0x2635, 0xC32F, 0xBEE1, 0x35A2, 0x88CC, 0x2E39, | |
209 | 0x9357, 0x55F2, 0xFC82, 0x7A47, 0xC8AC, 0xBAE7, 0x322B, 0xE695, | |
210 | 0xC0A0, 0x1998, 0x9ED1, 0xA37F, 0x4466, 0x547E, 0x3BAB, 0x0B83, | |
211 | 0x8CCA, 0xC729, 0x6BD3, 0x283C, 0xA779, 0xBCE2, 0x161D, 0xAD76, | |
212 | 0xDB3B, 0x6456, 0x744E, 0x141E, 0x92DB, 0x0C0A, 0x486C, 0xB8E4, | |
213 | 0x9F5D, 0xBD6E, 0x43EF, 0xC4A6, 0x39A8, 0x31A4, 0xD337, 0xF28B, | |
214 | 0xD532, 0x8B43, 0x6E59, 0xDAB7, 0x018C, 0xB164, 0x9CD2, 0x49E0, | |
215 | 0xD8B4, 0xACFA, 0xF307, 0xCF25, 0xCAAF, 0xF48E, 0x47E9, 0x1018, | |
216 | 0x6FD5, 0xF088, 0x4A6F, 0x5C72, 0x3824, 0x57F1, 0x73C7, 0x9751, | |
217 | 0xCB23, 0xA17C, 0xE89C, 0x3E21, 0x96DD, 0x61DC, 0x0D86, 0x0F85, | |
218 | 0xE090, 0x7C42, 0x71C4, 0xCCAA, 0x90D8, 0x0605, 0xF701, 0x1C12, | |
219 | 0xC2A3, 0x6A5F, 0xAEF9, 0x69D0, 0x1791, 0x9958, 0x3A27, 0x27B9, | |
220 | 0xD938, 0xEB13, 0x2BB3, 0x2233, 0xD2BB, 0xA970, 0x0789, 0x33A7, | |
221 | 0x2DB6, 0x3C22, 0x1592, 0xC920, 0x8749, 0xAAFF, 0x5078, 0xA57A, | |
222 | 0x038F, 0x59F8, 0x0980, 0x1A17, 0x65DA, 0xD731, 0x84C6, 0xD0B8, | |
223 | 0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A, | |
224 | }; | |
225 | ||
b453872c JG |
226 | static inline u16 _S_(u16 v) |
227 | { | |
228 | u16 t = Sbox[Hi8(v)]; | |
229 | return Sbox[Lo8(v)] ^ ((t << 8) | (t >> 8)); | |
230 | } | |
231 | ||
b453872c JG |
232 | #define PHASE1_LOOP_COUNT 8 |
233 | ||
0edd5b44 JG |
234 | static void tkip_mixing_phase1(u16 * TTAK, const u8 * TK, const u8 * TA, |
235 | u32 IV32) | |
b453872c JG |
236 | { |
237 | int i, j; | |
238 | ||
239 | /* Initialize the 80-bit TTAK from TSC (IV32) and TA[0..5] */ | |
240 | TTAK[0] = Lo16(IV32); | |
241 | TTAK[1] = Hi16(IV32); | |
242 | TTAK[2] = Mk16(TA[1], TA[0]); | |
243 | TTAK[3] = Mk16(TA[3], TA[2]); | |
244 | TTAK[4] = Mk16(TA[5], TA[4]); | |
245 | ||
246 | for (i = 0; i < PHASE1_LOOP_COUNT; i++) { | |
247 | j = 2 * (i & 1); | |
248 | TTAK[0] += _S_(TTAK[4] ^ Mk16(TK[1 + j], TK[0 + j])); | |
249 | TTAK[1] += _S_(TTAK[0] ^ Mk16(TK[5 + j], TK[4 + j])); | |
250 | TTAK[2] += _S_(TTAK[1] ^ Mk16(TK[9 + j], TK[8 + j])); | |
251 | TTAK[3] += _S_(TTAK[2] ^ Mk16(TK[13 + j], TK[12 + j])); | |
252 | TTAK[4] += _S_(TTAK[3] ^ Mk16(TK[1 + j], TK[0 + j])) + i; | |
253 | } | |
254 | } | |
255 | ||
0edd5b44 | 256 | static void tkip_mixing_phase2(u8 * WEPSeed, const u8 * TK, const u16 * TTAK, |
b453872c JG |
257 | u16 IV16) |
258 | { | |
259 | /* Make temporary area overlap WEP seed so that the final copy can be | |
260 | * avoided on little endian hosts. */ | |
0edd5b44 | 261 | u16 *PPK = (u16 *) & WEPSeed[4]; |
b453872c JG |
262 | |
263 | /* Step 1 - make copy of TTAK and bring in TSC */ | |
264 | PPK[0] = TTAK[0]; | |
265 | PPK[1] = TTAK[1]; | |
266 | PPK[2] = TTAK[2]; | |
267 | PPK[3] = TTAK[3]; | |
268 | PPK[4] = TTAK[4]; | |
269 | PPK[5] = TTAK[4] + IV16; | |
270 | ||
271 | /* Step 2 - 96-bit bijective mixing using S-box */ | |
d9e94d56 AV |
272 | PPK[0] += _S_(PPK[5] ^ Mk16_le((__le16 *) & TK[0])); |
273 | PPK[1] += _S_(PPK[0] ^ Mk16_le((__le16 *) & TK[2])); | |
274 | PPK[2] += _S_(PPK[1] ^ Mk16_le((__le16 *) & TK[4])); | |
275 | PPK[3] += _S_(PPK[2] ^ Mk16_le((__le16 *) & TK[6])); | |
276 | PPK[4] += _S_(PPK[3] ^ Mk16_le((__le16 *) & TK[8])); | |
277 | PPK[5] += _S_(PPK[4] ^ Mk16_le((__le16 *) & TK[10])); | |
278 | ||
279 | PPK[0] += RotR1(PPK[5] ^ Mk16_le((__le16 *) & TK[12])); | |
280 | PPK[1] += RotR1(PPK[0] ^ Mk16_le((__le16 *) & TK[14])); | |
b453872c JG |
281 | PPK[2] += RotR1(PPK[1]); |
282 | PPK[3] += RotR1(PPK[2]); | |
283 | PPK[4] += RotR1(PPK[3]); | |
284 | PPK[5] += RotR1(PPK[4]); | |
285 | ||
286 | /* Step 3 - bring in last of TK bits, assign 24-bit WEP IV value | |
287 | * WEPSeed[0..2] is transmitted as WEP IV */ | |
288 | WEPSeed[0] = Hi8(IV16); | |
289 | WEPSeed[1] = (Hi8(IV16) | 0x20) & 0x7F; | |
290 | WEPSeed[2] = Lo8(IV16); | |
d9e94d56 | 291 | WEPSeed[3] = Lo8((PPK[5] ^ Mk16_le((__le16 *) & TK[0])) >> 1); |
b453872c JG |
292 | |
293 | #ifdef __BIG_ENDIAN | |
294 | { | |
295 | int i; | |
296 | for (i = 0; i < 6; i++) | |
297 | PPK[i] = (PPK[i] << 8) | (PPK[i] >> 8); | |
298 | } | |
299 | #endif | |
300 | } | |
301 | ||
274bfb8d | 302 | static int lib80211_tkip_hdr(struct sk_buff *skb, int hdr_len, |
9184d934 | 303 | u8 * rc4key, int keylen, void *priv) |
b453872c | 304 | { |
274bfb8d | 305 | struct lib80211_tkip_data *tkey = priv; |
9184d934 | 306 | u8 *pos; |
274bfb8d | 307 | struct ieee80211_hdr *hdr; |
b453872c | 308 | |
274bfb8d | 309 | hdr = (struct ieee80211_hdr *)skb->data; |
20d64713 | 310 | |
299af9d3 | 311 | if (skb_headroom(skb) < TKIP_HDR_LEN || skb->len < hdr_len) |
9184d934 ZY |
312 | return -1; |
313 | ||
314 | if (rc4key == NULL || keylen < 16) | |
315 | return -1; | |
b453872c | 316 | |
b453872c JG |
317 | if (!tkey->tx_phase1_done) { |
318 | tkip_mixing_phase1(tkey->tx_ttak, tkey->key, hdr->addr2, | |
319 | tkey->tx_iv32); | |
320 | tkey->tx_phase1_done = 1; | |
321 | } | |
322 | tkip_mixing_phase2(rc4key, tkey->key, tkey->tx_ttak, tkey->tx_iv16); | |
323 | ||
299af9d3 AT |
324 | pos = skb_push(skb, TKIP_HDR_LEN); |
325 | memmove(pos, pos + TKIP_HDR_LEN, hdr_len); | |
b453872c | 326 | pos += hdr_len; |
b453872c | 327 | |
31b59eae JK |
328 | *pos++ = *rc4key; |
329 | *pos++ = *(rc4key + 1); | |
330 | *pos++ = *(rc4key + 2); | |
0edd5b44 | 331 | *pos++ = (tkey->key_idx << 6) | (1 << 5) /* Ext IV included */ ; |
b453872c JG |
332 | *pos++ = tkey->tx_iv32 & 0xff; |
333 | *pos++ = (tkey->tx_iv32 >> 8) & 0xff; | |
334 | *pos++ = (tkey->tx_iv32 >> 16) & 0xff; | |
335 | *pos++ = (tkey->tx_iv32 >> 24) & 0xff; | |
336 | ||
9184d934 ZY |
337 | tkey->tx_iv16++; |
338 | if (tkey->tx_iv16 == 0) { | |
339 | tkey->tx_phase1_done = 0; | |
340 | tkey->tx_iv32++; | |
341 | } | |
b453872c | 342 | |
299af9d3 | 343 | return TKIP_HDR_LEN; |
31b59eae JK |
344 | } |
345 | ||
274bfb8d | 346 | static int lib80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv) |
31b59eae | 347 | { |
274bfb8d | 348 | struct lib80211_tkip_data *tkey = priv; |
608fb34c | 349 | SKCIPHER_REQUEST_ON_STACK(req, tkey->tx_tfm_arc4); |
31b59eae | 350 | int len; |
9184d934 ZY |
351 | u8 rc4key[16], *pos, *icv; |
352 | u32 crc; | |
31b59eae | 353 | struct scatterlist sg; |
608fb34c | 354 | int err; |
31b59eae | 355 | |
6eb6edf0 | 356 | if (tkey->flags & IEEE80211_CRYPTO_TKIP_COUNTERMEASURES) { |
e87cc472 JP |
357 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; |
358 | net_dbg_ratelimited("TKIP countermeasures: dropped TX packet to %pM\n", | |
359 | hdr->addr1); | |
31b59eae JK |
360 | return -1; |
361 | } | |
362 | ||
363 | if (skb_tailroom(skb) < 4 || skb->len < hdr_len) | |
364 | return -1; | |
365 | ||
366 | len = skb->len - hdr_len; | |
367 | pos = skb->data + hdr_len; | |
368 | ||
274bfb8d | 369 | if ((lib80211_tkip_hdr(skb, hdr_len, rc4key, 16, priv)) < 0) |
31b59eae JK |
370 | return -1; |
371 | ||
9184d934 | 372 | crc = ~crc32_le(~0, pos, len); |
d0833a6a | 373 | icv = skb_put(skb, 4); |
9184d934 ZY |
374 | icv[0] = crc; |
375 | icv[1] = crc >> 8; | |
376 | icv[2] = crc >> 16; | |
377 | icv[3] = crc >> 24; | |
378 | ||
608fb34c | 379 | crypto_skcipher_setkey(tkey->tx_tfm_arc4, rc4key, 16); |
fa05f128 | 380 | sg_init_one(&sg, pos, len + 4); |
608fb34c HX |
381 | skcipher_request_set_tfm(req, tkey->tx_tfm_arc4); |
382 | skcipher_request_set_callback(req, 0, NULL, NULL); | |
383 | skcipher_request_set_crypt(req, &sg, &sg, len + 4, NULL); | |
384 | err = crypto_skcipher_encrypt(req); | |
385 | skcipher_request_zero(req); | |
386 | return err; | |
b4328d87 ZY |
387 | } |
388 | ||
18379879 JG |
389 | /* |
390 | * deal with seq counter wrapping correctly. | |
391 | * refer to timer_after() for jiffies wrapping handling | |
392 | */ | |
393 | static inline int tkip_replay_check(u32 iv32_n, u16 iv16_n, | |
394 | u32 iv32_o, u16 iv16_o) | |
395 | { | |
396 | if ((s32)iv32_n - (s32)iv32_o < 0 || | |
397 | (iv32_n == iv32_o && iv16_n <= iv16_o)) | |
398 | return 1; | |
399 | return 0; | |
400 | } | |
401 | ||
274bfb8d | 402 | static int lib80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv) |
b453872c | 403 | { |
274bfb8d | 404 | struct lib80211_tkip_data *tkey = priv; |
608fb34c | 405 | SKCIPHER_REQUEST_ON_STACK(req, tkey->rx_tfm_arc4); |
b453872c JG |
406 | u8 rc4key[16]; |
407 | u8 keyidx, *pos; | |
408 | u32 iv32; | |
409 | u16 iv16; | |
274bfb8d | 410 | struct ieee80211_hdr *hdr; |
b453872c JG |
411 | u8 icv[4]; |
412 | u32 crc; | |
413 | struct scatterlist sg; | |
414 | int plen; | |
608fb34c | 415 | int err; |
b453872c | 416 | |
274bfb8d | 417 | hdr = (struct ieee80211_hdr *)skb->data; |
20d64713 | 418 | |
6eb6edf0 | 419 | if (tkey->flags & IEEE80211_CRYPTO_TKIP_COUNTERMEASURES) { |
e87cc472 JP |
420 | net_dbg_ratelimited("TKIP countermeasures: dropped received packet from %pM\n", |
421 | hdr->addr2); | |
20d64713 JK |
422 | return -1; |
423 | } | |
424 | ||
299af9d3 | 425 | if (skb->len < hdr_len + TKIP_HDR_LEN + 4) |
b453872c JG |
426 | return -1; |
427 | ||
b453872c JG |
428 | pos = skb->data + hdr_len; |
429 | keyidx = pos[3]; | |
430 | if (!(keyidx & (1 << 5))) { | |
e87cc472 JP |
431 | net_dbg_ratelimited("TKIP: received packet without ExtIV flag from %pM\n", |
432 | hdr->addr2); | |
b453872c JG |
433 | return -2; |
434 | } | |
435 | keyidx >>= 6; | |
436 | if (tkey->key_idx != keyidx) { | |
996bf99c JB |
437 | net_dbg_ratelimited("TKIP: RX tkey->key_idx=%d frame keyidx=%d\n", |
438 | tkey->key_idx, keyidx); | |
b453872c JG |
439 | return -6; |
440 | } | |
441 | if (!tkey->key_set) { | |
e87cc472 JP |
442 | net_dbg_ratelimited("TKIP: received packet from %pM with keyid=%d that does not have a configured key\n", |
443 | hdr->addr2, keyidx); | |
b453872c JG |
444 | return -3; |
445 | } | |
446 | iv16 = (pos[0] << 8) | pos[2]; | |
447 | iv32 = pos[4] | (pos[5] << 8) | (pos[6] << 16) | (pos[7] << 24); | |
299af9d3 | 448 | pos += TKIP_HDR_LEN; |
b453872c | 449 | |
b4328d87 | 450 | if (tkip_replay_check(iv32, iv16, tkey->rx_iv32, tkey->rx_iv16)) { |
6f16bf3b | 451 | #ifdef CONFIG_LIB80211_DEBUG |
e87cc472 JP |
452 | net_dbg_ratelimited("TKIP: replay detected: STA=%pM previous TSC %08x%04x received TSC %08x%04x\n", |
453 | hdr->addr2, tkey->rx_iv32, tkey->rx_iv16, | |
454 | iv32, iv16); | |
6f16bf3b | 455 | #endif |
b453872c JG |
456 | tkey->dot11RSNAStatsTKIPReplays++; |
457 | return -4; | |
458 | } | |
459 | ||
460 | if (iv32 != tkey->rx_iv32 || !tkey->rx_phase1_done) { | |
461 | tkip_mixing_phase1(tkey->rx_ttak, tkey->key, hdr->addr2, iv32); | |
462 | tkey->rx_phase1_done = 1; | |
463 | } | |
464 | tkip_mixing_phase2(rc4key, tkey->key, tkey->rx_ttak, iv16); | |
465 | ||
466 | plen = skb->len - hdr_len - 12; | |
467 | ||
608fb34c | 468 | crypto_skcipher_setkey(tkey->rx_tfm_arc4, rc4key, 16); |
fa05f128 | 469 | sg_init_one(&sg, pos, plen + 4); |
608fb34c HX |
470 | skcipher_request_set_tfm(req, tkey->rx_tfm_arc4); |
471 | skcipher_request_set_callback(req, 0, NULL, NULL); | |
472 | skcipher_request_set_crypt(req, &sg, &sg, plen + 4, NULL); | |
473 | err = crypto_skcipher_decrypt(req); | |
474 | skcipher_request_zero(req); | |
475 | if (err) { | |
e87cc472 JP |
476 | net_dbg_ratelimited("TKIP: failed to decrypt received packet from %pM\n", |
477 | hdr->addr2); | |
f12cc209 HX |
478 | return -7; |
479 | } | |
b453872c JG |
480 | |
481 | crc = ~crc32_le(~0, pos, plen); | |
482 | icv[0] = crc; | |
483 | icv[1] = crc >> 8; | |
484 | icv[2] = crc >> 16; | |
485 | icv[3] = crc >> 24; | |
486 | if (memcmp(icv, pos + plen, 4) != 0) { | |
487 | if (iv32 != tkey->rx_iv32) { | |
488 | /* Previously cached Phase1 result was already lost, so | |
489 | * it needs to be recalculated for the next packet. */ | |
490 | tkey->rx_phase1_done = 0; | |
491 | } | |
6f16bf3b | 492 | #ifdef CONFIG_LIB80211_DEBUG |
e87cc472 JP |
493 | net_dbg_ratelimited("TKIP: ICV error detected: STA=%pM\n", |
494 | hdr->addr2); | |
6f16bf3b | 495 | #endif |
b453872c JG |
496 | tkey->dot11RSNAStatsTKIPICVErrors++; |
497 | return -5; | |
498 | } | |
499 | ||
500 | /* Update real counters only after Michael MIC verification has | |
501 | * completed */ | |
502 | tkey->rx_iv32_new = iv32; | |
503 | tkey->rx_iv16_new = iv16; | |
504 | ||
505 | /* Remove IV and ICV */ | |
299af9d3 AT |
506 | memmove(skb->data + TKIP_HDR_LEN, skb->data, hdr_len); |
507 | skb_pull(skb, TKIP_HDR_LEN); | |
b453872c JG |
508 | skb_trim(skb, skb->len - 4); |
509 | ||
510 | return keyidx; | |
511 | } | |
512 | ||
608fb34c | 513 | static int michael_mic(struct crypto_ahash *tfm_michael, u8 * key, u8 * hdr, |
0edd5b44 | 514 | u8 * data, size_t data_len, u8 * mic) |
b453872c | 515 | { |
608fb34c | 516 | AHASH_REQUEST_ON_STACK(req, tfm_michael); |
b453872c | 517 | struct scatterlist sg[2]; |
608fb34c | 518 | int err; |
b453872c | 519 | |
5a656949 | 520 | if (tfm_michael == NULL) { |
e9c0268f | 521 | pr_warn("%s(): tfm_michael == NULL\n", __func__); |
b453872c JG |
522 | return -1; |
523 | } | |
fa05f128 | 524 | sg_init_table(sg, 2); |
642f1490 JA |
525 | sg_set_buf(&sg[0], hdr, 16); |
526 | sg_set_buf(&sg[1], data, data_len); | |
b453872c | 527 | |
608fb34c | 528 | if (crypto_ahash_setkey(tfm_michael, key, 8)) |
35058687 | 529 | return -1; |
b453872c | 530 | |
608fb34c HX |
531 | ahash_request_set_tfm(req, tfm_michael); |
532 | ahash_request_set_callback(req, 0, NULL, NULL); | |
533 | ahash_request_set_crypt(req, sg, mic, data_len + 16); | |
534 | err = crypto_ahash_digest(req); | |
535 | ahash_request_zero(req); | |
536 | return err; | |
b453872c JG |
537 | } |
538 | ||
0edd5b44 | 539 | static void michael_mic_hdr(struct sk_buff *skb, u8 * hdr) |
b453872c | 540 | { |
274bfb8d | 541 | struct ieee80211_hdr *hdr11; |
b453872c | 542 | |
274bfb8d | 543 | hdr11 = (struct ieee80211_hdr *)skb->data; |
ea284152 | 544 | |
274bfb8d | 545 | switch (le16_to_cpu(hdr11->frame_control) & |
b453872c JG |
546 | (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) { |
547 | case IEEE80211_FCTL_TODS: | |
0edd5b44 JG |
548 | memcpy(hdr, hdr11->addr3, ETH_ALEN); /* DA */ |
549 | memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN); /* SA */ | |
b453872c JG |
550 | break; |
551 | case IEEE80211_FCTL_FROMDS: | |
0edd5b44 JG |
552 | memcpy(hdr, hdr11->addr1, ETH_ALEN); /* DA */ |
553 | memcpy(hdr + ETH_ALEN, hdr11->addr3, ETH_ALEN); /* SA */ | |
b453872c JG |
554 | break; |
555 | case IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS: | |
0edd5b44 JG |
556 | memcpy(hdr, hdr11->addr3, ETH_ALEN); /* DA */ |
557 | memcpy(hdr + ETH_ALEN, hdr11->addr4, ETH_ALEN); /* SA */ | |
b453872c JG |
558 | break; |
559 | case 0: | |
0edd5b44 JG |
560 | memcpy(hdr, hdr11->addr1, ETH_ALEN); /* DA */ |
561 | memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN); /* SA */ | |
b453872c JG |
562 | break; |
563 | } | |
564 | ||
274bfb8d | 565 | if (ieee80211_is_data_qos(hdr11->frame_control)) { |
3f6ff6ba | 566 | hdr[12] = le16_to_cpu(*((__le16 *)ieee80211_get_qos_ctl(hdr11))) |
274bfb8d | 567 | & IEEE80211_QOS_CTL_TID_MASK; |
ea284152 ZY |
568 | } else |
569 | hdr[12] = 0; /* priority */ | |
570 | ||
0edd5b44 | 571 | hdr[13] = hdr[14] = hdr[15] = 0; /* reserved */ |
b453872c JG |
572 | } |
573 | ||
274bfb8d | 574 | static int lib80211_michael_mic_add(struct sk_buff *skb, int hdr_len, |
0edd5b44 | 575 | void *priv) |
b453872c | 576 | { |
274bfb8d | 577 | struct lib80211_tkip_data *tkey = priv; |
b453872c JG |
578 | u8 *pos; |
579 | ||
580 | if (skb_tailroom(skb) < 8 || skb->len < hdr_len) { | |
581 | printk(KERN_DEBUG "Invalid packet for Michael MIC add " | |
582 | "(tailroom=%d hdr_len=%d skb->len=%d)\n", | |
583 | skb_tailroom(skb), hdr_len, skb->len); | |
584 | return -1; | |
585 | } | |
586 | ||
587 | michael_mic_hdr(skb, tkey->tx_hdr); | |
588 | pos = skb_put(skb, 8); | |
5a656949 | 589 | if (michael_mic(tkey->tx_tfm_michael, &tkey->key[16], tkey->tx_hdr, |
b453872c JG |
590 | skb->data + hdr_len, skb->len - 8 - hdr_len, pos)) |
591 | return -1; | |
592 | ||
593 | return 0; | |
594 | } | |
595 | ||
274bfb8d JL |
596 | static void lib80211_michael_mic_failure(struct net_device *dev, |
597 | struct ieee80211_hdr *hdr, | |
ee34af37 | 598 | int keyidx) |
b453872c JG |
599 | { |
600 | union iwreq_data wrqu; | |
601 | struct iw_michaelmicfailure ev; | |
602 | ||
603 | /* TODO: needed parameters: count, keyid, key type, TSC */ | |
604 | memset(&ev, 0, sizeof(ev)); | |
605 | ev.flags = keyidx & IW_MICFAILURE_KEY_ID; | |
606 | if (hdr->addr1[0] & 0x01) | |
607 | ev.flags |= IW_MICFAILURE_GROUP; | |
608 | else | |
609 | ev.flags |= IW_MICFAILURE_PAIRWISE; | |
610 | ev.src_addr.sa_family = ARPHRD_ETHER; | |
611 | memcpy(ev.src_addr.sa_data, hdr->addr2, ETH_ALEN); | |
612 | memset(&wrqu, 0, sizeof(wrqu)); | |
613 | wrqu.data.length = sizeof(ev); | |
0edd5b44 | 614 | wireless_send_event(dev, IWEVMICHAELMICFAILURE, &wrqu, (char *)&ev); |
b453872c | 615 | } |
b453872c | 616 | |
274bfb8d | 617 | static int lib80211_michael_mic_verify(struct sk_buff *skb, int keyidx, |
0edd5b44 | 618 | int hdr_len, void *priv) |
b453872c | 619 | { |
274bfb8d | 620 | struct lib80211_tkip_data *tkey = priv; |
b453872c JG |
621 | u8 mic[8]; |
622 | ||
623 | if (!tkey->key_set) | |
624 | return -1; | |
625 | ||
626 | michael_mic_hdr(skb, tkey->rx_hdr); | |
5a656949 | 627 | if (michael_mic(tkey->rx_tfm_michael, &tkey->key[24], tkey->rx_hdr, |
b453872c JG |
628 | skb->data + hdr_len, skb->len - 8 - hdr_len, mic)) |
629 | return -1; | |
630 | if (memcmp(mic, skb->data + skb->len - 8, 8) != 0) { | |
274bfb8d JL |
631 | struct ieee80211_hdr *hdr; |
632 | hdr = (struct ieee80211_hdr *)skb->data; | |
b453872c | 633 | printk(KERN_DEBUG "%s: Michael MIC verification failed for " |
e174961c JB |
634 | "MSDU from %pM keyidx=%d\n", |
635 | skb->dev ? skb->dev->name : "N/A", hdr->addr2, | |
b453872c JG |
636 | keyidx); |
637 | if (skb->dev) | |
274bfb8d | 638 | lib80211_michael_mic_failure(skb->dev, hdr, keyidx); |
b453872c JG |
639 | tkey->dot11RSNAStatsTKIPLocalMICFailures++; |
640 | return -1; | |
641 | } | |
642 | ||
643 | /* Update TSC counters for RX now that the packet verification has | |
644 | * completed. */ | |
645 | tkey->rx_iv32 = tkey->rx_iv32_new; | |
646 | tkey->rx_iv16 = tkey->rx_iv16_new; | |
647 | ||
648 | skb_trim(skb, skb->len - 8); | |
649 | ||
650 | return 0; | |
651 | } | |
652 | ||
274bfb8d | 653 | static int lib80211_tkip_set_key(void *key, int len, u8 * seq, void *priv) |
b453872c | 654 | { |
274bfb8d | 655 | struct lib80211_tkip_data *tkey = priv; |
b453872c | 656 | int keyidx; |
608fb34c HX |
657 | struct crypto_ahash *tfm = tkey->tx_tfm_michael; |
658 | struct crypto_skcipher *tfm2 = tkey->tx_tfm_arc4; | |
659 | struct crypto_ahash *tfm3 = tkey->rx_tfm_michael; | |
660 | struct crypto_skcipher *tfm4 = tkey->rx_tfm_arc4; | |
b453872c JG |
661 | |
662 | keyidx = tkey->key_idx; | |
663 | memset(tkey, 0, sizeof(*tkey)); | |
664 | tkey->key_idx = keyidx; | |
5a656949 ZY |
665 | tkey->tx_tfm_michael = tfm; |
666 | tkey->tx_tfm_arc4 = tfm2; | |
667 | tkey->rx_tfm_michael = tfm3; | |
668 | tkey->rx_tfm_arc4 = tfm4; | |
b453872c JG |
669 | if (len == TKIP_KEY_LEN) { |
670 | memcpy(tkey->key, key, TKIP_KEY_LEN); | |
671 | tkey->key_set = 1; | |
0edd5b44 | 672 | tkey->tx_iv16 = 1; /* TSC is initialized to 1 */ |
b453872c JG |
673 | if (seq) { |
674 | tkey->rx_iv32 = (seq[5] << 24) | (seq[4] << 16) | | |
0edd5b44 | 675 | (seq[3] << 8) | seq[2]; |
b453872c JG |
676 | tkey->rx_iv16 = (seq[1] << 8) | seq[0]; |
677 | } | |
678 | } else if (len == 0) | |
679 | tkey->key_set = 0; | |
680 | else | |
681 | return -1; | |
682 | ||
683 | return 0; | |
684 | } | |
685 | ||
274bfb8d | 686 | static int lib80211_tkip_get_key(void *key, int len, u8 * seq, void *priv) |
b453872c | 687 | { |
274bfb8d | 688 | struct lib80211_tkip_data *tkey = priv; |
b453872c JG |
689 | |
690 | if (len < TKIP_KEY_LEN) | |
691 | return -1; | |
692 | ||
693 | if (!tkey->key_set) | |
694 | return 0; | |
695 | memcpy(key, tkey->key, TKIP_KEY_LEN); | |
696 | ||
697 | if (seq) { | |
698 | /* Return the sequence number of the last transmitted frame. */ | |
699 | u16 iv16 = tkey->tx_iv16; | |
700 | u32 iv32 = tkey->tx_iv32; | |
701 | if (iv16 == 0) | |
702 | iv32--; | |
703 | iv16--; | |
704 | seq[0] = tkey->tx_iv16; | |
705 | seq[1] = tkey->tx_iv16 >> 8; | |
706 | seq[2] = tkey->tx_iv32; | |
707 | seq[3] = tkey->tx_iv32 >> 8; | |
708 | seq[4] = tkey->tx_iv32 >> 16; | |
709 | seq[5] = tkey->tx_iv32 >> 24; | |
710 | } | |
711 | ||
712 | return TKIP_KEY_LEN; | |
713 | } | |
714 | ||
6bbefe86 | 715 | static void lib80211_tkip_print_stats(struct seq_file *m, void *priv) |
b453872c | 716 | { |
274bfb8d | 717 | struct lib80211_tkip_data *tkip = priv; |
6bbefe86 DH |
718 | seq_printf(m, |
719 | "key[%d] alg=TKIP key_set=%d " | |
720 | "tx_pn=%02x%02x%02x%02x%02x%02x " | |
721 | "rx_pn=%02x%02x%02x%02x%02x%02x " | |
722 | "replays=%d icv_errors=%d local_mic_failures=%d\n", | |
723 | tkip->key_idx, tkip->key_set, | |
724 | (tkip->tx_iv32 >> 24) & 0xff, | |
725 | (tkip->tx_iv32 >> 16) & 0xff, | |
726 | (tkip->tx_iv32 >> 8) & 0xff, | |
727 | tkip->tx_iv32 & 0xff, | |
728 | (tkip->tx_iv16 >> 8) & 0xff, | |
729 | tkip->tx_iv16 & 0xff, | |
730 | (tkip->rx_iv32 >> 24) & 0xff, | |
731 | (tkip->rx_iv32 >> 16) & 0xff, | |
732 | (tkip->rx_iv32 >> 8) & 0xff, | |
733 | tkip->rx_iv32 & 0xff, | |
734 | (tkip->rx_iv16 >> 8) & 0xff, | |
735 | tkip->rx_iv16 & 0xff, | |
736 | tkip->dot11RSNAStatsTKIPReplays, | |
737 | tkip->dot11RSNAStatsTKIPICVErrors, | |
738 | tkip->dot11RSNAStatsTKIPLocalMICFailures); | |
b453872c JG |
739 | } |
740 | ||
274bfb8d | 741 | static struct lib80211_crypto_ops lib80211_crypt_tkip = { |
74079fdc | 742 | .name = "TKIP", |
274bfb8d JL |
743 | .init = lib80211_tkip_init, |
744 | .deinit = lib80211_tkip_deinit, | |
274bfb8d JL |
745 | .encrypt_mpdu = lib80211_tkip_encrypt, |
746 | .decrypt_mpdu = lib80211_tkip_decrypt, | |
747 | .encrypt_msdu = lib80211_michael_mic_add, | |
748 | .decrypt_msdu = lib80211_michael_mic_verify, | |
749 | .set_key = lib80211_tkip_set_key, | |
750 | .get_key = lib80211_tkip_get_key, | |
751 | .print_stats = lib80211_tkip_print_stats, | |
1264fc04 JK |
752 | .extra_mpdu_prefix_len = 4 + 4, /* IV + ExtIV */ |
753 | .extra_mpdu_postfix_len = 4, /* ICV */ | |
754 | .extra_msdu_postfix_len = 8, /* MIC */ | |
274bfb8d JL |
755 | .get_flags = lib80211_tkip_get_flags, |
756 | .set_flags = lib80211_tkip_set_flags, | |
74079fdc | 757 | .owner = THIS_MODULE, |
b453872c JG |
758 | }; |
759 | ||
274bfb8d | 760 | static int __init lib80211_crypto_tkip_init(void) |
b453872c | 761 | { |
274bfb8d | 762 | return lib80211_register_crypto_ops(&lib80211_crypt_tkip); |
b453872c JG |
763 | } |
764 | ||
274bfb8d | 765 | static void __exit lib80211_crypto_tkip_exit(void) |
b453872c | 766 | { |
274bfb8d | 767 | lib80211_unregister_crypto_ops(&lib80211_crypt_tkip); |
b453872c JG |
768 | } |
769 | ||
274bfb8d JL |
770 | module_init(lib80211_crypto_tkip_init); |
771 | module_exit(lib80211_crypto_tkip_exit); |