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-rw-r--r--net/ieee80211/ieee80211_crypt_ccmp.c493
1 files changed, 0 insertions, 493 deletions
diff --git a/net/ieee80211/ieee80211_crypt_ccmp.c b/net/ieee80211/ieee80211_crypt_ccmp.c
deleted file mode 100644
index 208bf35b5546..000000000000
--- a/net/ieee80211/ieee80211_crypt_ccmp.c
+++ /dev/null
@@ -1,493 +0,0 @@
1/*
2 * Host AP crypt: host-based CCMP encryption implementation for Host AP driver
3 *
4 * Copyright (c) 2003-2004, Jouni Malinen <j@w1.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/kernel.h>
13#include <linux/err.h>
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/slab.h>
17#include <linux/random.h>
18#include <linux/skbuff.h>
19#include <linux/netdevice.h>
20#include <linux/if_ether.h>
21#include <linux/if_arp.h>
22#include <asm/string.h>
23#include <linux/wireless.h>
24
25#include <net/ieee80211.h>
26
27#include <linux/crypto.h>
28
29MODULE_AUTHOR("Jouni Malinen");
30MODULE_DESCRIPTION("Host AP crypt: CCMP");
31MODULE_LICENSE("GPL");
32
33#define AES_BLOCK_LEN 16
34#define CCMP_HDR_LEN 8
35#define CCMP_MIC_LEN 8
36#define CCMP_TK_LEN 16
37#define CCMP_PN_LEN 6
38
39struct ieee80211_ccmp_data {
40 u8 key[CCMP_TK_LEN];
41 int key_set;
42
43 u8 tx_pn[CCMP_PN_LEN];
44 u8 rx_pn[CCMP_PN_LEN];
45
46 u32 dot11RSNAStatsCCMPFormatErrors;
47 u32 dot11RSNAStatsCCMPReplays;
48 u32 dot11RSNAStatsCCMPDecryptErrors;
49
50 int key_idx;
51
52 struct crypto_cipher *tfm;
53
54 /* scratch buffers for virt_to_page() (crypto API) */
55 u8 tx_b0[AES_BLOCK_LEN], tx_b[AES_BLOCK_LEN],
56 tx_e[AES_BLOCK_LEN], tx_s0[AES_BLOCK_LEN];
57 u8 rx_b0[AES_BLOCK_LEN], rx_b[AES_BLOCK_LEN], rx_a[AES_BLOCK_LEN];
58};
59
60static inline void ieee80211_ccmp_aes_encrypt(struct crypto_cipher *tfm,
61 const u8 pt[16], u8 ct[16])
62{
63 crypto_cipher_encrypt_one(tfm, ct, pt);
64}
65
66static void *ieee80211_ccmp_init(int key_idx)
67{
68 struct ieee80211_ccmp_data *priv;
69
70 priv = kzalloc(sizeof(*priv), GFP_ATOMIC);
71 if (priv == NULL)
72 goto fail;
73 priv->key_idx = key_idx;
74
75 priv->tfm = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
76 if (IS_ERR(priv->tfm)) {
77 printk(KERN_DEBUG "ieee80211_crypt_ccmp: could not allocate "
78 "crypto API aes\n");
79 priv->tfm = NULL;
80 goto fail;
81 }
82
83 return priv;
84
85 fail:
86 if (priv) {
87 if (priv->tfm)
88 crypto_free_cipher(priv->tfm);
89 kfree(priv);
90 }
91
92 return NULL;
93}
94
95static void ieee80211_ccmp_deinit(void *priv)
96{
97 struct ieee80211_ccmp_data *_priv = priv;
98 if (_priv && _priv->tfm)
99 crypto_free_cipher(_priv->tfm);
100 kfree(priv);
101}
102
103static inline void xor_block(u8 * b, u8 * a, size_t len)
104{
105 int i;
106 for (i = 0; i < len; i++)
107 b[i] ^= a[i];
108}
109
110static void ccmp_init_blocks(struct crypto_cipher *tfm,
111 struct ieee80211_hdr_4addr *hdr,
112 u8 * pn, size_t dlen, u8 * b0, u8 * auth, u8 * s0)
113{
114 u8 *pos, qc = 0;
115 size_t aad_len;
116 u16 fc;
117 int a4_included, qc_included;
118 u8 aad[2 * AES_BLOCK_LEN];
119
120 fc = le16_to_cpu(hdr->frame_ctl);
121 a4_included = ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
122 (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS));
123 qc_included = ((WLAN_FC_GET_TYPE(fc) == IEEE80211_FTYPE_DATA) &&
124 (WLAN_FC_GET_STYPE(fc) & IEEE80211_STYPE_QOS_DATA));
125 aad_len = 22;
126 if (a4_included)
127 aad_len += 6;
128 if (qc_included) {
129 pos = (u8 *) & hdr->addr4;
130 if (a4_included)
131 pos += 6;
132 qc = *pos & 0x0f;
133 aad_len += 2;
134 }
135
136 /* CCM Initial Block:
137 * Flag (Include authentication header, M=3 (8-octet MIC),
138 * L=1 (2-octet Dlen))
139 * Nonce: 0x00 | A2 | PN
140 * Dlen */
141 b0[0] = 0x59;
142 b0[1] = qc;
143 memcpy(b0 + 2, hdr->addr2, ETH_ALEN);
144 memcpy(b0 + 8, pn, CCMP_PN_LEN);
145 b0[14] = (dlen >> 8) & 0xff;
146 b0[15] = dlen & 0xff;
147
148 /* AAD:
149 * FC with bits 4..6 and 11..13 masked to zero; 14 is always one
150 * A1 | A2 | A3
151 * SC with bits 4..15 (seq#) masked to zero
152 * A4 (if present)
153 * QC (if present)
154 */
155 pos = (u8 *) hdr;
156 aad[0] = 0; /* aad_len >> 8 */
157 aad[1] = aad_len & 0xff;
158 aad[2] = pos[0] & 0x8f;
159 aad[3] = pos[1] & 0xc7;
160 memcpy(aad + 4, hdr->addr1, 3 * ETH_ALEN);
161 pos = (u8 *) & hdr->seq_ctl;
162 aad[22] = pos[0] & 0x0f;
163 aad[23] = 0; /* all bits masked */
164 memset(aad + 24, 0, 8);
165 if (a4_included)
166 memcpy(aad + 24, hdr->addr4, ETH_ALEN);
167 if (qc_included) {
168 aad[a4_included ? 30 : 24] = qc;
169 /* rest of QC masked */
170 }
171
172 /* Start with the first block and AAD */
173 ieee80211_ccmp_aes_encrypt(tfm, b0, auth);
174 xor_block(auth, aad, AES_BLOCK_LEN);
175 ieee80211_ccmp_aes_encrypt(tfm, auth, auth);
176 xor_block(auth, &aad[AES_BLOCK_LEN], AES_BLOCK_LEN);
177 ieee80211_ccmp_aes_encrypt(tfm, auth, auth);
178 b0[0] &= 0x07;
179 b0[14] = b0[15] = 0;
180 ieee80211_ccmp_aes_encrypt(tfm, b0, s0);
181}
182
183static int ieee80211_ccmp_hdr(struct sk_buff *skb, int hdr_len,
184 u8 *aeskey, int keylen, void *priv)
185{
186 struct ieee80211_ccmp_data *key = priv;
187 int i;
188 u8 *pos;
189
190 if (skb_headroom(skb) < CCMP_HDR_LEN || skb->len < hdr_len)
191 return -1;
192
193 if (aeskey != NULL && keylen >= CCMP_TK_LEN)
194 memcpy(aeskey, key->key, CCMP_TK_LEN);
195
196 pos = skb_push(skb, CCMP_HDR_LEN);
197 memmove(pos, pos + CCMP_HDR_LEN, hdr_len);
198 pos += hdr_len;
199
200 i = CCMP_PN_LEN - 1;
201 while (i >= 0) {
202 key->tx_pn[i]++;
203 if (key->tx_pn[i] != 0)
204 break;
205 i--;
206 }
207
208 *pos++ = key->tx_pn[5];
209 *pos++ = key->tx_pn[4];
210 *pos++ = 0;
211 *pos++ = (key->key_idx << 6) | (1 << 5) /* Ext IV included */ ;
212 *pos++ = key->tx_pn[3];
213 *pos++ = key->tx_pn[2];
214 *pos++ = key->tx_pn[1];
215 *pos++ = key->tx_pn[0];
216
217 return CCMP_HDR_LEN;
218}
219
220static int ieee80211_ccmp_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
221{
222 struct ieee80211_ccmp_data *key = priv;
223 int data_len, i, blocks, last, len;
224 u8 *pos, *mic;
225 struct ieee80211_hdr_4addr *hdr;
226 u8 *b0 = key->tx_b0;
227 u8 *b = key->tx_b;
228 u8 *e = key->tx_e;
229 u8 *s0 = key->tx_s0;
230
231 if (skb_tailroom(skb) < CCMP_MIC_LEN || skb->len < hdr_len)
232 return -1;
233
234 data_len = skb->len - hdr_len;
235 len = ieee80211_ccmp_hdr(skb, hdr_len, NULL, 0, priv);
236 if (len < 0)
237 return -1;
238
239 pos = skb->data + hdr_len + CCMP_HDR_LEN;
240 mic = skb_put(skb, CCMP_MIC_LEN);
241 hdr = (struct ieee80211_hdr_4addr *)skb->data;
242 ccmp_init_blocks(key->tfm, hdr, key->tx_pn, data_len, b0, b, s0);
243
244 blocks = DIV_ROUND_UP(data_len, AES_BLOCK_LEN);
245 last = data_len % AES_BLOCK_LEN;
246
247 for (i = 1; i <= blocks; i++) {
248 len = (i == blocks && last) ? last : AES_BLOCK_LEN;
249 /* Authentication */
250 xor_block(b, pos, len);
251 ieee80211_ccmp_aes_encrypt(key->tfm, b, b);
252 /* Encryption, with counter */
253 b0[14] = (i >> 8) & 0xff;
254 b0[15] = i & 0xff;
255 ieee80211_ccmp_aes_encrypt(key->tfm, b0, e);
256 xor_block(pos, e, len);
257 pos += len;
258 }
259
260 for (i = 0; i < CCMP_MIC_LEN; i++)
261 mic[i] = b[i] ^ s0[i];
262
263 return 0;
264}
265
266/*
267 * deal with seq counter wrapping correctly.
268 * refer to timer_after() for jiffies wrapping handling
269 */
270static inline int ccmp_replay_check(u8 *pn_n, u8 *pn_o)
271{
272 u32 iv32_n, iv16_n;
273 u32 iv32_o, iv16_o;
274
275 iv32_n = (pn_n[0] << 24) | (pn_n[1] << 16) | (pn_n[2] << 8) | pn_n[3];
276 iv16_n = (pn_n[4] << 8) | pn_n[5];
277
278 iv32_o = (pn_o[0] << 24) | (pn_o[1] << 16) | (pn_o[2] << 8) | pn_o[3];
279 iv16_o = (pn_o[4] << 8) | pn_o[5];
280
281 if ((s32)iv32_n - (s32)iv32_o < 0 ||
282 (iv32_n == iv32_o && iv16_n <= iv16_o))
283 return 1;
284 return 0;
285}
286
287static int ieee80211_ccmp_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
288{
289 struct ieee80211_ccmp_data *key = priv;
290 u8 keyidx, *pos;
291 struct ieee80211_hdr_4addr *hdr;
292 u8 *b0 = key->rx_b0;
293 u8 *b = key->rx_b;
294 u8 *a = key->rx_a;
295 u8 pn[6];
296 int i, blocks, last, len;
297 size_t data_len = skb->len - hdr_len - CCMP_HDR_LEN - CCMP_MIC_LEN;
298 u8 *mic = skb->data + skb->len - CCMP_MIC_LEN;
299 DECLARE_MAC_BUF(mac);
300
301 if (skb->len < hdr_len + CCMP_HDR_LEN + CCMP_MIC_LEN) {
302 key->dot11RSNAStatsCCMPFormatErrors++;
303 return -1;
304 }
305
306 hdr = (struct ieee80211_hdr_4addr *)skb->data;
307 pos = skb->data + hdr_len;
308 keyidx = pos[3];
309 if (!(keyidx & (1 << 5))) {
310 if (net_ratelimit()) {
311 printk(KERN_DEBUG "CCMP: received packet without ExtIV"
312 " flag from %s\n", print_mac(mac, hdr->addr2));
313 }
314 key->dot11RSNAStatsCCMPFormatErrors++;
315 return -2;
316 }
317 keyidx >>= 6;
318 if (key->key_idx != keyidx) {
319 printk(KERN_DEBUG "CCMP: RX tkey->key_idx=%d frame "
320 "keyidx=%d priv=%p\n", key->key_idx, keyidx, priv);
321 return -6;
322 }
323 if (!key->key_set) {
324 if (net_ratelimit()) {
325 printk(KERN_DEBUG "CCMP: received packet from %s"
326 " with keyid=%d that does not have a configured"
327 " key\n", print_mac(mac, hdr->addr2), keyidx);
328 }
329 return -3;
330 }
331
332 pn[0] = pos[7];
333 pn[1] = pos[6];
334 pn[2] = pos[5];
335 pn[3] = pos[4];
336 pn[4] = pos[1];
337 pn[5] = pos[0];
338 pos += 8;
339
340 if (ccmp_replay_check(pn, key->rx_pn)) {
341 if (ieee80211_ratelimit_debug(IEEE80211_DL_DROP)) {
342 IEEE80211_DEBUG_DROP("CCMP: replay detected: STA=%s "
343 "previous PN %02x%02x%02x%02x%02x%02x "
344 "received PN %02x%02x%02x%02x%02x%02x\n",
345 print_mac(mac, hdr->addr2),
346 key->rx_pn[0], key->rx_pn[1], key->rx_pn[2],
347 key->rx_pn[3], key->rx_pn[4], key->rx_pn[5],
348 pn[0], pn[1], pn[2], pn[3], pn[4], pn[5]);
349 }
350 key->dot11RSNAStatsCCMPReplays++;
351 return -4;
352 }
353
354 ccmp_init_blocks(key->tfm, hdr, pn, data_len, b0, a, b);
355 xor_block(mic, b, CCMP_MIC_LEN);
356
357 blocks = DIV_ROUND_UP(data_len, AES_BLOCK_LEN);
358 last = data_len % AES_BLOCK_LEN;
359
360 for (i = 1; i <= blocks; i++) {
361 len = (i == blocks && last) ? last : AES_BLOCK_LEN;
362 /* Decrypt, with counter */
363 b0[14] = (i >> 8) & 0xff;
364 b0[15] = i & 0xff;
365 ieee80211_ccmp_aes_encrypt(key->tfm, b0, b);
366 xor_block(pos, b, len);
367 /* Authentication */
368 xor_block(a, pos, len);
369 ieee80211_ccmp_aes_encrypt(key->tfm, a, a);
370 pos += len;
371 }
372
373 if (memcmp(mic, a, CCMP_MIC_LEN) != 0) {
374 if (net_ratelimit()) {
375 printk(KERN_DEBUG "CCMP: decrypt failed: STA="
376 "%s\n", print_mac(mac, hdr->addr2));
377 }
378 key->dot11RSNAStatsCCMPDecryptErrors++;
379 return -5;
380 }
381
382 memcpy(key->rx_pn, pn, CCMP_PN_LEN);
383
384 /* Remove hdr and MIC */
385 memmove(skb->data + CCMP_HDR_LEN, skb->data, hdr_len);
386 skb_pull(skb, CCMP_HDR_LEN);
387 skb_trim(skb, skb->len - CCMP_MIC_LEN);
388
389 return keyidx;
390}
391
392static int ieee80211_ccmp_set_key(void *key, int len, u8 * seq, void *priv)
393{
394 struct ieee80211_ccmp_data *data = priv;
395 int keyidx;
396 struct crypto_cipher *tfm = data->tfm;
397
398 keyidx = data->key_idx;
399 memset(data, 0, sizeof(*data));
400 data->key_idx = keyidx;
401 data->tfm = tfm;
402 if (len == CCMP_TK_LEN) {
403 memcpy(data->key, key, CCMP_TK_LEN);
404 data->key_set = 1;
405 if (seq) {
406 data->rx_pn[0] = seq[5];
407 data->rx_pn[1] = seq[4];
408 data->rx_pn[2] = seq[3];
409 data->rx_pn[3] = seq[2];
410 data->rx_pn[4] = seq[1];
411 data->rx_pn[5] = seq[0];
412 }
413 crypto_cipher_setkey(data->tfm, data->key, CCMP_TK_LEN);
414 } else if (len == 0)
415 data->key_set = 0;
416 else
417 return -1;
418
419 return 0;
420}
421
422static int ieee80211_ccmp_get_key(void *key, int len, u8 * seq, void *priv)
423{
424 struct ieee80211_ccmp_data *data = priv;
425
426 if (len < CCMP_TK_LEN)
427 return -1;
428
429 if (!data->key_set)
430 return 0;
431 memcpy(key, data->key, CCMP_TK_LEN);
432
433 if (seq) {
434 seq[0] = data->tx_pn[5];
435 seq[1] = data->tx_pn[4];
436 seq[2] = data->tx_pn[3];
437 seq[3] = data->tx_pn[2];
438 seq[4] = data->tx_pn[1];
439 seq[5] = data->tx_pn[0];
440 }
441
442 return CCMP_TK_LEN;
443}
444
445static char *ieee80211_ccmp_print_stats(char *p, void *priv)
446{
447 struct ieee80211_ccmp_data *ccmp = priv;
448
449 p += sprintf(p, "key[%d] alg=CCMP key_set=%d "
450 "tx_pn=%02x%02x%02x%02x%02x%02x "
451 "rx_pn=%02x%02x%02x%02x%02x%02x "
452 "format_errors=%d replays=%d decrypt_errors=%d\n",
453 ccmp->key_idx, ccmp->key_set,
454 ccmp->tx_pn[0], ccmp->tx_pn[1], ccmp->tx_pn[2],
455 ccmp->tx_pn[3], ccmp->tx_pn[4], ccmp->tx_pn[5],
456 ccmp->rx_pn[0], ccmp->rx_pn[1], ccmp->rx_pn[2],
457 ccmp->rx_pn[3], ccmp->rx_pn[4], ccmp->rx_pn[5],
458 ccmp->dot11RSNAStatsCCMPFormatErrors,
459 ccmp->dot11RSNAStatsCCMPReplays,
460 ccmp->dot11RSNAStatsCCMPDecryptErrors);
461
462 return p;
463}
464
465static struct ieee80211_crypto_ops ieee80211_crypt_ccmp = {
466 .name = "CCMP",
467 .init = ieee80211_ccmp_init,
468 .deinit = ieee80211_ccmp_deinit,
469 .build_iv = ieee80211_ccmp_hdr,
470 .encrypt_mpdu = ieee80211_ccmp_encrypt,
471 .decrypt_mpdu = ieee80211_ccmp_decrypt,
472 .encrypt_msdu = NULL,
473 .decrypt_msdu = NULL,
474 .set_key = ieee80211_ccmp_set_key,
475 .get_key = ieee80211_ccmp_get_key,
476 .print_stats = ieee80211_ccmp_print_stats,
477 .extra_mpdu_prefix_len = CCMP_HDR_LEN,
478 .extra_mpdu_postfix_len = CCMP_MIC_LEN,
479 .owner = THIS_MODULE,
480};
481
482static int __init ieee80211_crypto_ccmp_init(void)
483{
484 return ieee80211_register_crypto_ops(&ieee80211_crypt_ccmp);
485}
486
487static void __exit ieee80211_crypto_ccmp_exit(void)
488{
489 ieee80211_unregister_crypto_ops(&ieee80211_crypt_ccmp);
490}
491
492module_init(ieee80211_crypto_ccmp_init);
493module_exit(ieee80211_crypto_ccmp_exit);
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-14 03:13:42 -0500