1 /*
2 * Host AP crypt: host-based TKIP encryption implementation for Host AP driver
3 *
4 * Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi>
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
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/slab.h>
15 #include <linux/random.h>
16 #include <linux/skbuff.h>
17 #include <linux/netdevice.h>
18 #include <linux/if_ether.h>
19 #include <linux/if_arp.h>
20 #include <linux/string.h>
21
22 #include "ieee80211.h"
23
24 #include <linux/crypto.h>
25 #include <linux/scatterlist.h>
26 #include <linux/crc32.h>
27
28 MODULE_AUTHOR("Jouni Malinen");
29 MODULE_DESCRIPTION("Host AP crypt: TKIP");
30 MODULE_LICENSE("GPL");
31
32 struct ieee80211_tkip_data {
33 #define TKIP_KEY_LEN 32
34 u8 key[TKIP_KEY_LEN];
35 int key_set;
36
37 u32 tx_iv32;
38 u16 tx_iv16;
39 u16 tx_ttak[5];
40 int tx_phase1_done;
41
42 u32 rx_iv32;
43 u16 rx_iv16;
44 u16 rx_ttak[5];
45 int rx_phase1_done;
46 u32 rx_iv32_new;
47 u16 rx_iv16_new;
48
49 u32 dot11RSNAStatsTKIPReplays;
50 u32 dot11RSNAStatsTKIPICVErrors;
51 u32 dot11RSNAStatsTKIPLocalMICFailures;
52
53 int key_idx;
54
55 struct crypto_blkcipher *rx_tfm_arc4;
56 struct crypto_hash *rx_tfm_michael;
57 struct crypto_blkcipher *tx_tfm_arc4;
58 struct crypto_hash *tx_tfm_michael;
59
60 /* scratch buffers for virt_to_page() (crypto API) */
61 u8 rx_hdr[16], tx_hdr[16];
62 };
63
ieee80211_tkip_init(int key_idx)64 static void *ieee80211_tkip_init(int key_idx)
65 {
66 struct ieee80211_tkip_data *priv;
67
68 priv = kzalloc(sizeof(*priv), GFP_ATOMIC);
69 if (priv == NULL)
70 goto fail;
71 priv->key_idx = key_idx;
72
73 priv->tx_tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0,
74 CRYPTO_ALG_ASYNC);
75 if (IS_ERR(priv->tx_tfm_arc4)) {
76 printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate "
77 "crypto API arc4\n");
78 priv->tx_tfm_arc4 = NULL;
79 goto fail;
80 }
81
82 priv->tx_tfm_michael = crypto_alloc_hash("michael_mic", 0,
83 CRYPTO_ALG_ASYNC);
84 if (IS_ERR(priv->tx_tfm_michael)) {
85 printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate "
86 "crypto API michael_mic\n");
87 priv->tx_tfm_michael = NULL;
88 goto fail;
89 }
90
91 priv->rx_tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0,
92 CRYPTO_ALG_ASYNC);
93 if (IS_ERR(priv->rx_tfm_arc4)) {
94 printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate "
95 "crypto API arc4\n");
96 priv->rx_tfm_arc4 = NULL;
97 goto fail;
98 }
99
100 priv->rx_tfm_michael = crypto_alloc_hash("michael_mic", 0,
101 CRYPTO_ALG_ASYNC);
102 if (IS_ERR(priv->rx_tfm_michael)) {
103 printk(KERN_DEBUG "ieee80211_crypt_tkip: could not allocate "
104 "crypto API michael_mic\n");
105 priv->rx_tfm_michael = NULL;
106 goto fail;
107 }
108
109 return priv;
110
111 fail:
112 if (priv) {
113 if (priv->tx_tfm_michael)
114 crypto_free_hash(priv->tx_tfm_michael);
115 if (priv->tx_tfm_arc4)
116 crypto_free_blkcipher(priv->tx_tfm_arc4);
117 if (priv->rx_tfm_michael)
118 crypto_free_hash(priv->rx_tfm_michael);
119 if (priv->rx_tfm_arc4)
120 crypto_free_blkcipher(priv->rx_tfm_arc4);
121 kfree(priv);
122 }
123
124 return NULL;
125 }
126
127
ieee80211_tkip_deinit(void * priv)128 static void ieee80211_tkip_deinit(void *priv)
129 {
130 struct ieee80211_tkip_data *_priv = priv;
131
132 if (_priv) {
133 if (_priv->tx_tfm_michael)
134 crypto_free_hash(_priv->tx_tfm_michael);
135 if (_priv->tx_tfm_arc4)
136 crypto_free_blkcipher(_priv->tx_tfm_arc4);
137 if (_priv->rx_tfm_michael)
138 crypto_free_hash(_priv->rx_tfm_michael);
139 if (_priv->rx_tfm_arc4)
140 crypto_free_blkcipher(_priv->rx_tfm_arc4);
141 }
142 kfree(priv);
143 }
144
145
RotR1(u16 val)146 static inline u16 RotR1(u16 val)
147 {
148 return (val >> 1) | (val << 15);
149 }
150
151
Lo8(u16 val)152 static inline u8 Lo8(u16 val)
153 {
154 return val & 0xff;
155 }
156
157
Hi8(u16 val)158 static inline u8 Hi8(u16 val)
159 {
160 return val >> 8;
161 }
162
163
Lo16(u32 val)164 static inline u16 Lo16(u32 val)
165 {
166 return val & 0xffff;
167 }
168
169
Hi16(u32 val)170 static inline u16 Hi16(u32 val)
171 {
172 return val >> 16;
173 }
174
175
Mk16(u8 hi,u8 lo)176 static inline u16 Mk16(u8 hi, u8 lo)
177 {
178 return lo | (((u16) hi) << 8);
179 }
180
181
Mk16_le(u16 * v)182 static inline u16 Mk16_le(u16 *v)
183 {
184 return le16_to_cpu(*v);
185 }
186
187
188 static const u16 Sbox[256] = {
189 0xC6A5, 0xF884, 0xEE99, 0xF68D, 0xFF0D, 0xD6BD, 0xDEB1, 0x9154,
190 0x6050, 0x0203, 0xCEA9, 0x567D, 0xE719, 0xB562, 0x4DE6, 0xEC9A,
191 0x8F45, 0x1F9D, 0x8940, 0xFA87, 0xEF15, 0xB2EB, 0x8EC9, 0xFB0B,
192 0x41EC, 0xB367, 0x5FFD, 0x45EA, 0x23BF, 0x53F7, 0xE496, 0x9B5B,
193 0x75C2, 0xE11C, 0x3DAE, 0x4C6A, 0x6C5A, 0x7E41, 0xF502, 0x834F,
194 0x685C, 0x51F4, 0xD134, 0xF908, 0xE293, 0xAB73, 0x6253, 0x2A3F,
195 0x080C, 0x9552, 0x4665, 0x9D5E, 0x3028, 0x37A1, 0x0A0F, 0x2FB5,
196 0x0E09, 0x2436, 0x1B9B, 0xDF3D, 0xCD26, 0x4E69, 0x7FCD, 0xEA9F,
197 0x121B, 0x1D9E, 0x5874, 0x342E, 0x362D, 0xDCB2, 0xB4EE, 0x5BFB,
198 0xA4F6, 0x764D, 0xB761, 0x7DCE, 0x527B, 0xDD3E, 0x5E71, 0x1397,
199 0xA6F5, 0xB968, 0x0000, 0xC12C, 0x4060, 0xE31F, 0x79C8, 0xB6ED,
200 0xD4BE, 0x8D46, 0x67D9, 0x724B, 0x94DE, 0x98D4, 0xB0E8, 0x854A,
201 0xBB6B, 0xC52A, 0x4FE5, 0xED16, 0x86C5, 0x9AD7, 0x6655, 0x1194,
202 0x8ACF, 0xE910, 0x0406, 0xFE81, 0xA0F0, 0x7844, 0x25BA, 0x4BE3,
203 0xA2F3, 0x5DFE, 0x80C0, 0x058A, 0x3FAD, 0x21BC, 0x7048, 0xF104,
204 0x63DF, 0x77C1, 0xAF75, 0x4263, 0x2030, 0xE51A, 0xFD0E, 0xBF6D,
205 0x814C, 0x1814, 0x2635, 0xC32F, 0xBEE1, 0x35A2, 0x88CC, 0x2E39,
206 0x9357, 0x55F2, 0xFC82, 0x7A47, 0xC8AC, 0xBAE7, 0x322B, 0xE695,
207 0xC0A0, 0x1998, 0x9ED1, 0xA37F, 0x4466, 0x547E, 0x3BAB, 0x0B83,
208 0x8CCA, 0xC729, 0x6BD3, 0x283C, 0xA779, 0xBCE2, 0x161D, 0xAD76,
209 0xDB3B, 0x6456, 0x744E, 0x141E, 0x92DB, 0x0C0A, 0x486C, 0xB8E4,
210 0x9F5D, 0xBD6E, 0x43EF, 0xC4A6, 0x39A8, 0x31A4, 0xD337, 0xF28B,
211 0xD532, 0x8B43, 0x6E59, 0xDAB7, 0x018C, 0xB164, 0x9CD2, 0x49E0,
212 0xD8B4, 0xACFA, 0xF307, 0xCF25, 0xCAAF, 0xF48E, 0x47E9, 0x1018,
213 0x6FD5, 0xF088, 0x4A6F, 0x5C72, 0x3824, 0x57F1, 0x73C7, 0x9751,
214 0xCB23, 0xA17C, 0xE89C, 0x3E21, 0x96DD, 0x61DC, 0x0D86, 0x0F85,
215 0xE090, 0x7C42, 0x71C4, 0xCCAA, 0x90D8, 0x0605, 0xF701, 0x1C12,
216 0xC2A3, 0x6A5F, 0xAEF9, 0x69D0, 0x1791, 0x9958, 0x3A27, 0x27B9,
217 0xD938, 0xEB13, 0x2BB3, 0x2233, 0xD2BB, 0xA970, 0x0789, 0x33A7,
218 0x2DB6, 0x3C22, 0x1592, 0xC920, 0x8749, 0xAAFF, 0x5078, 0xA57A,
219 0x038F, 0x59F8, 0x0980, 0x1A17, 0x65DA, 0xD731, 0x84C6, 0xD0B8,
220 0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A,
221 };
222
223
_S_(u16 v)224 static inline u16 _S_(u16 v)
225 {
226 u16 t = Sbox[Hi8(v)];
227 return Sbox[Lo8(v)] ^ ((t << 8) | (t >> 8));
228 }
229
230
231 #define PHASE1_LOOP_COUNT 8
232
233
tkip_mixing_phase1(u16 * TTAK,const u8 * TK,const u8 * TA,u32 IV32)234 static void tkip_mixing_phase1(u16 *TTAK, const u8 *TK, const u8 *TA, u32 IV32)
235 {
236 int i, j;
237
238 /* Initialize the 80-bit TTAK from TSC (IV32) and TA[0..5] */
239 TTAK[0] = Lo16(IV32);
240 TTAK[1] = Hi16(IV32);
241 TTAK[2] = Mk16(TA[1], TA[0]);
242 TTAK[3] = Mk16(TA[3], TA[2]);
243 TTAK[4] = Mk16(TA[5], TA[4]);
244
245 for (i = 0; i < PHASE1_LOOP_COUNT; i++) {
246 j = 2 * (i & 1);
247 TTAK[0] += _S_(TTAK[4] ^ Mk16(TK[1 + j], TK[0 + j]));
248 TTAK[1] += _S_(TTAK[0] ^ Mk16(TK[5 + j], TK[4 + j]));
249 TTAK[2] += _S_(TTAK[1] ^ Mk16(TK[9 + j], TK[8 + j]));
250 TTAK[3] += _S_(TTAK[2] ^ Mk16(TK[13 + j], TK[12 + j]));
251 TTAK[4] += _S_(TTAK[3] ^ Mk16(TK[1 + j], TK[0 + j])) + i;
252 }
253 }
254
255
tkip_mixing_phase2(u8 * WEPSeed,const u8 * TK,const u16 * TTAK,u16 IV16)256 static void tkip_mixing_phase2(u8 *WEPSeed, const u8 *TK, const u16 *TTAK,
257 u16 IV16)
258 {
259 /*
260 * Make temporary area overlap WEP seed so that the final copy can be
261 * avoided on little endian hosts.
262 */
263 u16 *PPK = (u16 *) &WEPSeed[4];
264
265 /* Step 1 - make copy of TTAK and bring in TSC */
266 PPK[0] = TTAK[0];
267 PPK[1] = TTAK[1];
268 PPK[2] = TTAK[2];
269 PPK[3] = TTAK[3];
270 PPK[4] = TTAK[4];
271 PPK[5] = TTAK[4] + IV16;
272
273 /* Step 2 - 96-bit bijective mixing using S-box */
274 PPK[0] += _S_(PPK[5] ^ Mk16_le((u16 *) &TK[0]));
275 PPK[1] += _S_(PPK[0] ^ Mk16_le((u16 *) &TK[2]));
276 PPK[2] += _S_(PPK[1] ^ Mk16_le((u16 *) &TK[4]));
277 PPK[3] += _S_(PPK[2] ^ Mk16_le((u16 *) &TK[6]));
278 PPK[4] += _S_(PPK[3] ^ Mk16_le((u16 *) &TK[8]));
279 PPK[5] += _S_(PPK[4] ^ Mk16_le((u16 *) &TK[10]));
280
281 PPK[0] += RotR1(PPK[5] ^ Mk16_le((u16 *) &TK[12]));
282 PPK[1] += RotR1(PPK[0] ^ Mk16_le((u16 *) &TK[14]));
283 PPK[2] += RotR1(PPK[1]);
284 PPK[3] += RotR1(PPK[2]);
285 PPK[4] += RotR1(PPK[3]);
286 PPK[5] += RotR1(PPK[4]);
287
288 /*
289 * Step 3 - bring in last of TK bits, assign 24-bit WEP IV value
290 * WEPSeed[0..2] is transmitted as WEP IV
291 */
292 WEPSeed[0] = Hi8(IV16);
293 WEPSeed[1] = (Hi8(IV16) | 0x20) & 0x7F;
294 WEPSeed[2] = Lo8(IV16);
295 WEPSeed[3] = Lo8((PPK[5] ^ Mk16_le((u16 *) &TK[0])) >> 1);
296
297 #ifdef __BIG_ENDIAN
298 {
299 int i;
300
301 for (i = 0; i < 6; i++)
302 PPK[i] = (PPK[i] << 8) | (PPK[i] >> 8);
303 }
304 #endif
305 }
306
307
ieee80211_tkip_encrypt(struct sk_buff * skb,int hdr_len,void * priv)308 static int ieee80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
309 {
310 struct ieee80211_tkip_data *tkey = priv;
311 int len;
312 u8 *pos;
313 struct rtl_80211_hdr_4addr *hdr;
314 cb_desc *tcb_desc = (cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE);
315 struct blkcipher_desc desc = {.tfm = tkey->tx_tfm_arc4};
316 int ret = 0;
317 u8 rc4key[16], *icv;
318 u32 crc;
319 struct scatterlist sg;
320
321 if (skb_headroom(skb) < 8 || skb_tailroom(skb) < 4 ||
322 skb->len < hdr_len)
323 return -1;
324
325 hdr = (struct rtl_80211_hdr_4addr *) skb->data;
326
327 if (!tcb_desc->bHwSec) {
328 if (!tkey->tx_phase1_done) {
329 tkip_mixing_phase1(tkey->tx_ttak, tkey->key, hdr->addr2,
330 tkey->tx_iv32);
331 tkey->tx_phase1_done = 1;
332 }
333 tkip_mixing_phase2(rc4key, tkey->key, tkey->tx_ttak, tkey->tx_iv16);
334 } else
335 tkey->tx_phase1_done = 1;
336
337
338 len = skb->len - hdr_len;
339 pos = skb_push(skb, 8);
340 memmove(pos, pos + 8, hdr_len);
341 pos += hdr_len;
342
343 if (tcb_desc->bHwSec) {
344 *pos++ = Hi8(tkey->tx_iv16);
345 *pos++ = (Hi8(tkey->tx_iv16) | 0x20) & 0x7F;
346 *pos++ = Lo8(tkey->tx_iv16);
347 } else {
348 *pos++ = rc4key[0];
349 *pos++ = rc4key[1];
350 *pos++ = rc4key[2];
351 }
352
353 *pos++ = (tkey->key_idx << 6) | (1 << 5) /* Ext IV included */;
354 *pos++ = tkey->tx_iv32 & 0xff;
355 *pos++ = (tkey->tx_iv32 >> 8) & 0xff;
356 *pos++ = (tkey->tx_iv32 >> 16) & 0xff;
357 *pos++ = (tkey->tx_iv32 >> 24) & 0xff;
358
359 if (!tcb_desc->bHwSec) {
360 icv = skb_put(skb, 4);
361 crc = ~crc32_le(~0, pos, len);
362 icv[0] = crc;
363 icv[1] = crc >> 8;
364 icv[2] = crc >> 16;
365 icv[3] = crc >> 24;
366 crypto_blkcipher_setkey(tkey->tx_tfm_arc4, rc4key, 16);
367 sg_init_one(&sg, pos, len+4);
368 ret = crypto_blkcipher_encrypt(&desc, &sg, &sg, len + 4);
369 }
370
371 tkey->tx_iv16++;
372 if (tkey->tx_iv16 == 0) {
373 tkey->tx_phase1_done = 0;
374 tkey->tx_iv32++;
375 }
376
377 if (!tcb_desc->bHwSec)
378 return ret;
379 else
380 return 0;
381
382
383 }
384
ieee80211_tkip_decrypt(struct sk_buff * skb,int hdr_len,void * priv)385 static int ieee80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
386 {
387 struct ieee80211_tkip_data *tkey = priv;
388 u8 keyidx, *pos;
389 u32 iv32;
390 u16 iv16;
391 struct rtl_80211_hdr_4addr *hdr;
392 cb_desc *tcb_desc = (cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE);
393 struct blkcipher_desc desc = {.tfm = tkey->rx_tfm_arc4};
394 u8 rc4key[16];
395 u8 icv[4];
396 u32 crc;
397 struct scatterlist sg;
398 int plen;
399
400 if (skb->len < hdr_len + 8 + 4)
401 return -1;
402
403 hdr = (struct rtl_80211_hdr_4addr *) skb->data;
404 pos = skb->data + hdr_len;
405 keyidx = pos[3];
406 if (!(keyidx & (1 << 5))) {
407 if (net_ratelimit()) {
408 printk(KERN_DEBUG "TKIP: received packet without ExtIV"
409 " flag from %pM\n", hdr->addr2);
410 }
411 return -2;
412 }
413 keyidx >>= 6;
414 if (tkey->key_idx != keyidx) {
415 printk(KERN_DEBUG "TKIP: RX tkey->key_idx=%d frame "
416 "keyidx=%d priv=%p\n", tkey->key_idx, keyidx, priv);
417 return -6;
418 }
419 if (!tkey->key_set) {
420 if (net_ratelimit()) {
421 printk(KERN_DEBUG "TKIP: received packet from %pM"
422 " with keyid=%d that does not have a configured"
423 " key\n", hdr->addr2, keyidx);
424 }
425 return -3;
426 }
427 iv16 = (pos[0] << 8) | pos[2];
428 iv32 = pos[4] | (pos[5] << 8) | (pos[6] << 16) | (pos[7] << 24);
429 pos += 8;
430
431 if (!tcb_desc->bHwSec) {
432 if (iv32 < tkey->rx_iv32 ||
433 (iv32 == tkey->rx_iv32 && iv16 <= tkey->rx_iv16)) {
434 if (net_ratelimit()) {
435 printk(KERN_DEBUG "TKIP: replay detected: STA=%pM"
436 " previous TSC %08x%04x received TSC "
437 "%08x%04x\n", hdr->addr2,
438 tkey->rx_iv32, tkey->rx_iv16, iv32, iv16);
439 }
440 tkey->dot11RSNAStatsTKIPReplays++;
441 return -4;
442 }
443
444 if (iv32 != tkey->rx_iv32 || !tkey->rx_phase1_done) {
445 tkip_mixing_phase1(tkey->rx_ttak, tkey->key, hdr->addr2, iv32);
446 tkey->rx_phase1_done = 1;
447 }
448 tkip_mixing_phase2(rc4key, tkey->key, tkey->rx_ttak, iv16);
449
450 plen = skb->len - hdr_len - 12;
451
452 crypto_blkcipher_setkey(tkey->rx_tfm_arc4, rc4key, 16);
453 sg_init_one(&sg, pos, plen+4);
454
455 if (crypto_blkcipher_decrypt(&desc, &sg, &sg, plen + 4)) {
456 if (net_ratelimit()) {
457 printk(KERN_DEBUG ": TKIP: failed to decrypt "
458 "received packet from %pM\n",
459 hdr->addr2);
460 }
461 return -7;
462 }
463
464 crc = ~crc32_le(~0, pos, plen);
465 icv[0] = crc;
466 icv[1] = crc >> 8;
467 icv[2] = crc >> 16;
468 icv[3] = crc >> 24;
469
470 if (memcmp(icv, pos + plen, 4) != 0) {
471 if (iv32 != tkey->rx_iv32) {
472 /*
473 * Previously cached Phase1 result was already
474 * lost, so it needs to be recalculated for the
475 * next packet.
476 */
477 tkey->rx_phase1_done = 0;
478 }
479 if (net_ratelimit()) {
480 printk(KERN_DEBUG "TKIP: ICV error detected: STA="
481 "%pM\n", hdr->addr2);
482 }
483 tkey->dot11RSNAStatsTKIPICVErrors++;
484 return -5;
485 }
486
487 }
488
489 /*
490 * Update real counters only after Michael MIC verification has
491 * completed.
492 */
493 tkey->rx_iv32_new = iv32;
494 tkey->rx_iv16_new = iv16;
495
496 /* Remove IV and ICV */
497 memmove(skb->data + 8, skb->data, hdr_len);
498 skb_pull(skb, 8);
499 skb_trim(skb, skb->len - 4);
500
501 return keyidx;
502 }
503
michael_mic(struct crypto_hash * tfm_michael,u8 * key,u8 * hdr,u8 * data,size_t data_len,u8 * mic)504 static int michael_mic(struct crypto_hash *tfm_michael, u8 *key, u8 *hdr,
505 u8 *data, size_t data_len, u8 *mic)
506 {
507 struct hash_desc desc;
508 struct scatterlist sg[2];
509
510 if (tfm_michael == NULL) {
511 printk(KERN_WARNING "michael_mic: tfm_michael == NULL\n");
512 return -1;
513 }
514
515 sg_init_table(sg, 2);
516 sg_set_buf(&sg[0], hdr, 16);
517 sg_set_buf(&sg[1], data, data_len);
518
519 if (crypto_hash_setkey(tfm_michael, key, 8))
520 return -1;
521
522 desc.tfm = tfm_michael;
523 desc.flags = 0;
524 return crypto_hash_digest(&desc, sg, data_len + 16, mic);
525 }
526
michael_mic_hdr(struct sk_buff * skb,u8 * hdr)527 static void michael_mic_hdr(struct sk_buff *skb, u8 *hdr)
528 {
529 struct rtl_80211_hdr_4addr *hdr11;
530
531 hdr11 = (struct rtl_80211_hdr_4addr *) skb->data;
532 switch (le16_to_cpu(hdr11->frame_ctl) &
533 (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) {
534 case IEEE80211_FCTL_TODS:
535 memcpy(hdr, hdr11->addr3, ETH_ALEN); /* DA */
536 memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN); /* SA */
537 break;
538 case IEEE80211_FCTL_FROMDS:
539 memcpy(hdr, hdr11->addr1, ETH_ALEN); /* DA */
540 memcpy(hdr + ETH_ALEN, hdr11->addr3, ETH_ALEN); /* SA */
541 break;
542 case IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS:
543 memcpy(hdr, hdr11->addr3, ETH_ALEN); /* DA */
544 memcpy(hdr + ETH_ALEN, hdr11->addr4, ETH_ALEN); /* SA */
545 break;
546 case 0:
547 memcpy(hdr, hdr11->addr1, ETH_ALEN); /* DA */
548 memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN); /* SA */
549 break;
550 }
551
552 hdr[12] = 0; /* priority */
553
554 hdr[13] = hdr[14] = hdr[15] = 0; /* reserved */
555 }
556
557
ieee80211_michael_mic_add(struct sk_buff * skb,int hdr_len,void * priv)558 static int ieee80211_michael_mic_add(struct sk_buff *skb, int hdr_len, void *priv)
559 {
560 struct ieee80211_tkip_data *tkey = priv;
561 u8 *pos;
562 struct rtl_80211_hdr_4addr *hdr;
563
564 hdr = (struct rtl_80211_hdr_4addr *) skb->data;
565
566 if (skb_tailroom(skb) < 8 || skb->len < hdr_len) {
567 printk(KERN_DEBUG "Invalid packet for Michael MIC add "
568 "(tailroom=%d hdr_len=%d skb->len=%d)\n",
569 skb_tailroom(skb), hdr_len, skb->len);
570 return -1;
571 }
572
573 michael_mic_hdr(skb, tkey->tx_hdr);
574
575 // { david, 2006.9.1
576 // fix the wpa process with wmm enabled.
577 if (IEEE80211_QOS_HAS_SEQ(le16_to_cpu(hdr->frame_ctl)))
578 tkey->tx_hdr[12] = *(skb->data + hdr_len - 2) & 0x07;
579 // }
580 pos = skb_put(skb, 8);
581
582 if (michael_mic(tkey->tx_tfm_michael, &tkey->key[16], tkey->tx_hdr,
583 skb->data + hdr_len, skb->len - 8 - hdr_len, pos))
584 return -1;
585
586 return 0;
587 }
588
ieee80211_michael_mic_failure(struct net_device * dev,struct rtl_80211_hdr_4addr * hdr,int keyidx)589 static void ieee80211_michael_mic_failure(struct net_device *dev,
590 struct rtl_80211_hdr_4addr *hdr,
591 int keyidx)
592 {
593 union iwreq_data wrqu;
594 struct iw_michaelmicfailure ev;
595
596 /* TODO: needed parameters: count, keyid, key type, TSC */
597 memset(&ev, 0, sizeof(ev));
598 ev.flags = keyidx & IW_MICFAILURE_KEY_ID;
599 if (hdr->addr1[0] & 0x01)
600 ev.flags |= IW_MICFAILURE_GROUP;
601 else
602 ev.flags |= IW_MICFAILURE_PAIRWISE;
603 ev.src_addr.sa_family = ARPHRD_ETHER;
604 memcpy(ev.src_addr.sa_data, hdr->addr2, ETH_ALEN);
605 memset(&wrqu, 0, sizeof(wrqu));
606 wrqu.data.length = sizeof(ev);
607 wireless_send_event(dev, IWEVMICHAELMICFAILURE, &wrqu, (char *) &ev);
608 }
609
ieee80211_michael_mic_verify(struct sk_buff * skb,int keyidx,int hdr_len,void * priv)610 static int ieee80211_michael_mic_verify(struct sk_buff *skb, int keyidx,
611 int hdr_len, void *priv)
612 {
613 struct ieee80211_tkip_data *tkey = priv;
614 u8 mic[8];
615 struct rtl_80211_hdr_4addr *hdr;
616
617 hdr = (struct rtl_80211_hdr_4addr *) skb->data;
618
619 if (!tkey->key_set)
620 return -1;
621
622 michael_mic_hdr(skb, tkey->rx_hdr);
623 // { david, 2006.9.1
624 // fix the wpa process with wmm enabled.
625 if (IEEE80211_QOS_HAS_SEQ(le16_to_cpu(hdr->frame_ctl)))
626 tkey->rx_hdr[12] = *(skb->data + hdr_len - 2) & 0x07;
627 // }
628
629 if (michael_mic(tkey->rx_tfm_michael, &tkey->key[24], tkey->rx_hdr,
630 skb->data + hdr_len, skb->len - 8 - hdr_len, mic))
631 return -1;
632 if (memcmp(mic, skb->data + skb->len - 8, 8) != 0) {
633 struct rtl_80211_hdr_4addr *hdr;
634 hdr = (struct rtl_80211_hdr_4addr *) skb->data;
635
636 printk(KERN_DEBUG "%s: Michael MIC verification failed for "
637 "MSDU from %pM keyidx=%d\n",
638 skb->dev ? skb->dev->name : "N/A", hdr->addr2,
639 keyidx);
640 if (skb->dev)
641 ieee80211_michael_mic_failure(skb->dev, hdr, keyidx);
642 tkey->dot11RSNAStatsTKIPLocalMICFailures++;
643 return -1;
644 }
645
646 /*
647 * Update TSC counters for RX now that the packet verification has
648 * completed.
649 */
650 tkey->rx_iv32 = tkey->rx_iv32_new;
651 tkey->rx_iv16 = tkey->rx_iv16_new;
652
653 skb_trim(skb, skb->len - 8);
654
655 return 0;
656 }
657
658
ieee80211_tkip_set_key(void * key,int len,u8 * seq,void * priv)659 static int ieee80211_tkip_set_key(void *key, int len, u8 *seq, void *priv)
660 {
661 struct ieee80211_tkip_data *tkey = priv;
662 int keyidx;
663 struct crypto_hash *tfm = tkey->tx_tfm_michael;
664 struct crypto_blkcipher *tfm2 = tkey->tx_tfm_arc4;
665 struct crypto_hash *tfm3 = tkey->rx_tfm_michael;
666 struct crypto_blkcipher *tfm4 = tkey->rx_tfm_arc4;
667
668 keyidx = tkey->key_idx;
669 memset(tkey, 0, sizeof(*tkey));
670 tkey->key_idx = keyidx;
671 tkey->tx_tfm_michael = tfm;
672 tkey->tx_tfm_arc4 = tfm2;
673 tkey->rx_tfm_michael = tfm3;
674 tkey->rx_tfm_arc4 = tfm4;
675
676 if (len == TKIP_KEY_LEN) {
677 memcpy(tkey->key, key, TKIP_KEY_LEN);
678 tkey->key_set = 1;
679 tkey->tx_iv16 = 1; /* TSC is initialized to 1 */
680 if (seq) {
681 tkey->rx_iv32 = (seq[5] << 24) | (seq[4] << 16) |
682 (seq[3] << 8) | seq[2];
683 tkey->rx_iv16 = (seq[1] << 8) | seq[0];
684 }
685 } else if (len == 0)
686 tkey->key_set = 0;
687 else
688 return -1;
689
690 return 0;
691 }
692
693
ieee80211_tkip_get_key(void * key,int len,u8 * seq,void * priv)694 static int ieee80211_tkip_get_key(void *key, int len, u8 *seq, void *priv)
695 {
696 struct ieee80211_tkip_data *tkey = priv;
697
698 if (len < TKIP_KEY_LEN)
699 return -1;
700
701 if (!tkey->key_set)
702 return 0;
703 memcpy(key, tkey->key, TKIP_KEY_LEN);
704
705 if (seq) {
706 /* Return the sequence number of the last transmitted frame. */
707 u16 iv16 = tkey->tx_iv16;
708 u32 iv32 = tkey->tx_iv32;
709
710 if (iv16 == 0)
711 iv32--;
712 iv16--;
713 seq[0] = tkey->tx_iv16;
714 seq[1] = tkey->tx_iv16 >> 8;
715 seq[2] = tkey->tx_iv32;
716 seq[3] = tkey->tx_iv32 >> 8;
717 seq[4] = tkey->tx_iv32 >> 16;
718 seq[5] = tkey->tx_iv32 >> 24;
719 }
720
721 return TKIP_KEY_LEN;
722 }
723
724
ieee80211_tkip_print_stats(char * p,void * priv)725 static char *ieee80211_tkip_print_stats(char *p, void *priv)
726 {
727 struct ieee80211_tkip_data *tkip = priv;
728
729 p += sprintf(p, "key[%d] alg=TKIP key_set=%d "
730 "tx_pn=%02x%02x%02x%02x%02x%02x "
731 "rx_pn=%02x%02x%02x%02x%02x%02x "
732 "replays=%d icv_errors=%d local_mic_failures=%d\n",
733 tkip->key_idx, tkip->key_set,
734 (tkip->tx_iv32 >> 24) & 0xff,
735 (tkip->tx_iv32 >> 16) & 0xff,
736 (tkip->tx_iv32 >> 8) & 0xff,
737 tkip->tx_iv32 & 0xff,
738 (tkip->tx_iv16 >> 8) & 0xff,
739 tkip->tx_iv16 & 0xff,
740 (tkip->rx_iv32 >> 24) & 0xff,
741 (tkip->rx_iv32 >> 16) & 0xff,
742 (tkip->rx_iv32 >> 8) & 0xff,
743 tkip->rx_iv32 & 0xff,
744 (tkip->rx_iv16 >> 8) & 0xff,
745 tkip->rx_iv16 & 0xff,
746 tkip->dot11RSNAStatsTKIPReplays,
747 tkip->dot11RSNAStatsTKIPICVErrors,
748 tkip->dot11RSNAStatsTKIPLocalMICFailures);
749 return p;
750 }
751
752
753 static struct ieee80211_crypto_ops ieee80211_crypt_tkip = {
754 .name = "TKIP",
755 .init = ieee80211_tkip_init,
756 .deinit = ieee80211_tkip_deinit,
757 .encrypt_mpdu = ieee80211_tkip_encrypt,
758 .decrypt_mpdu = ieee80211_tkip_decrypt,
759 .encrypt_msdu = ieee80211_michael_mic_add,
760 .decrypt_msdu = ieee80211_michael_mic_verify,
761 .set_key = ieee80211_tkip_set_key,
762 .get_key = ieee80211_tkip_get_key,
763 .print_stats = ieee80211_tkip_print_stats,
764 .extra_prefix_len = 4 + 4, /* IV + ExtIV */
765 .extra_postfix_len = 8 + 4, /* MIC + ICV */
766 .owner = THIS_MODULE,
767 };
768
ieee80211_crypto_tkip_init(void)769 int __init ieee80211_crypto_tkip_init(void)
770 {
771 return ieee80211_register_crypto_ops(&ieee80211_crypt_tkip);
772 }
773
ieee80211_crypto_tkip_exit(void)774 void __exit ieee80211_crypto_tkip_exit(void)
775 {
776 ieee80211_unregister_crypto_ops(&ieee80211_crypt_tkip);
777 }
778
ieee80211_tkip_null(void)779 void ieee80211_tkip_null(void)
780 {
781 // printk("============>%s()\n", __func__);
782 return;
783 }
784