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path: root/drivers/staging/rtl8192e/rtllib_crypt_wep.c
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Diffstat (limited to 'drivers/staging/rtl8192e/rtllib_crypt_wep.c')
-rw-r--r--drivers/staging/rtl8192e/rtllib_crypt_wep.c371
1 files changed, 371 insertions, 0 deletions
diff --git a/drivers/staging/rtl8192e/rtllib_crypt_wep.c b/drivers/staging/rtl8192e/rtllib_crypt_wep.c
new file mode 100644
index 00000000000..38679223fa5
--- /dev/null
+++ b/drivers/staging/rtl8192e/rtllib_crypt_wep.c
@@ -0,0 +1,371 @@
1/*
2 * Host AP crypt: host-based WEP encryption implementation for Host AP driver
3 *
4 * Copyright (c) 2002-2004, 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/version.h>
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 <asm/string.h>
19#include "rtllib.h"
20
21#if (LINUX_VERSION_CODE > KERNEL_VERSION(2,6,20))
22#endif
23
24
25#if defined(BUILT_IN_CRYPTO) || (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
26#include "rtl_crypto.h"
27#else
28#include <linux/crypto.h>
29#endif
30
31#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,20)
32 #include <asm/scatterlist.h>
33#else
34 #include <linux/scatterlist.h>
35#endif
36#include <linux/crc32.h>
37/*
38#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
39#include "rtl_crypto.h"
40#else
41#include <linux/crypto.h>
42#endif
43
44#include <asm/scatterlist.h>
45#include <linux/crc32.h>
46*/
47struct prism2_wep_data {
48 u32 iv;
49#define WEP_KEY_LEN 13
50 u8 key[WEP_KEY_LEN + 1];
51 u8 key_len;
52 u8 key_idx;
53 #if ( defined(BUILT_IN_CRYPTO) || ((LINUX_VERSION_CODE < KERNEL_VERSION(2,6,21)) && (!OPENSUSE_SLED)) )
54 struct crypto_tfm *tfm;
55 #else
56 struct crypto_blkcipher *tx_tfm;
57 struct crypto_blkcipher *rx_tfm;
58 #endif
59};
60
61
62static void * prism2_wep_init(int keyidx)
63{
64 struct prism2_wep_data *priv;
65
66 priv = kmalloc(sizeof(*priv), GFP_ATOMIC);
67 if (priv == NULL)
68 goto fail;
69 memset(priv, 0, sizeof(*priv));
70 priv->key_idx = keyidx;
71
72 #if ( defined(BUILT_IN_CRYPTO) || ((LINUX_VERSION_CODE < KERNEL_VERSION(2,6,21)) && (!OPENSUSE_SLED)) )
73 priv->tfm = crypto_alloc_tfm("arc4", 0);
74 if (priv->tfm == NULL) {
75 printk(KERN_DEBUG "rtllib_crypt_wep: could not allocate "
76 "crypto API arc4\n");
77 goto fail;
78 }
79 #else
80 priv->tx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
81 if (IS_ERR(priv->tx_tfm)) {
82 printk(KERN_DEBUG "rtllib_crypt_wep: could not allocate "
83 "crypto API arc4\n");
84 priv->tx_tfm = NULL;
85 goto fail;
86 }
87 priv->rx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
88 if (IS_ERR(priv->rx_tfm)) {
89 printk(KERN_DEBUG "rtllib_crypt_wep: could not allocate "
90 "crypto API arc4\n");
91 priv->rx_tfm = NULL;
92 goto fail;
93 }
94 #endif
95
96 /* start WEP IV from a random value */
97 get_random_bytes(&priv->iv, 4);
98
99 return priv;
100
101fail:
102 #if ( defined(BUILT_IN_CRYPTO) || ((LINUX_VERSION_CODE < KERNEL_VERSION(2,6,21)) && (!OPENSUSE_SLED)) )
103 if (priv) {
104 if (priv->tfm)
105 crypto_free_tfm(priv->tfm);
106 kfree(priv);
107 }
108 #else
109 if (priv) {
110 if (priv->tx_tfm)
111 crypto_free_blkcipher(priv->tx_tfm);
112 if (priv->rx_tfm)
113 crypto_free_blkcipher(priv->rx_tfm);
114 kfree(priv);
115 }
116 #endif
117 return NULL;
118}
119
120
121static void prism2_wep_deinit(void *priv)
122{
123 struct prism2_wep_data *_priv = priv;
124 #if ( defined(BUILT_IN_CRYPTO) || ((LINUX_VERSION_CODE < KERNEL_VERSION(2,6,21)) && (!OPENSUSE_SLED)) )
125 if (_priv && _priv->tfm)
126 crypto_free_tfm(_priv->tfm);
127 #else
128 if (_priv) {
129 if (_priv->tx_tfm)
130 crypto_free_blkcipher(_priv->tx_tfm);
131 if (_priv->rx_tfm)
132 crypto_free_blkcipher(_priv->rx_tfm);
133 }
134 #endif
135 kfree(priv);
136}
137
138/* Perform WEP encryption on given skb that has at least 4 bytes of headroom
139 * for IV and 4 bytes of tailroom for ICV. Both IV and ICV will be transmitted,
140 * so the payload length increases with 8 bytes.
141 *
142 * WEP frame payload: IV + TX key idx, RC4(data), ICV = RC4(CRC32(data))
143 */
144static int prism2_wep_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
145{
146 struct prism2_wep_data *wep = priv;
147 u32 klen, len;
148 u8 key[WEP_KEY_LEN + 3];
149 u8 *pos;
150 cb_desc *tcb_desc = (cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE);
151 #if ( !defined(BUILT_IN_CRYPTO) && ((LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,21)) || (OPENSUSE_SLED)) )
152 struct blkcipher_desc desc = {.tfm = wep->tx_tfm};
153 #endif
154 u32 crc;
155 u8 *icv;
156 struct scatterlist sg;
157 if (skb_headroom(skb) < 4 || skb_tailroom(skb) < 4 ||
158 skb->len < hdr_len){
159 printk("Error!!!headroom=%d tailroom=%d skblen=%d hdr_len=%d\n",skb_headroom(skb),skb_tailroom(skb),skb->len,hdr_len);
160 return -1;
161 }
162 len = skb->len - hdr_len;
163 pos = skb_push(skb, 4);
164 memmove(pos, pos + 4, hdr_len);
165 pos += hdr_len;
166
167 klen = 3 + wep->key_len;
168
169 wep->iv++;
170
171 /* Fluhrer, Mantin, and Shamir have reported weaknesses in the key
172 * scheduling algorithm of RC4. At least IVs (KeyByte + 3, 0xff, N)
173 * can be used to speedup attacks, so avoid using them. */
174 if ((wep->iv & 0xff00) == 0xff00) {
175 u8 B = (wep->iv >> 16) & 0xff;
176 if (B >= 3 && B < klen)
177 wep->iv += 0x0100;
178 }
179
180 /* Prepend 24-bit IV to RC4 key and TX frame */
181 *pos++ = key[0] = (wep->iv >> 16) & 0xff;
182 *pos++ = key[1] = (wep->iv >> 8) & 0xff;
183 *pos++ = key[2] = wep->iv & 0xff;
184 *pos++ = wep->key_idx << 6;
185
186 /* Copy rest of the WEP key (the secret part) */
187 memcpy(key + 3, wep->key, wep->key_len);
188
189 if (!tcb_desc->bHwSec)
190 {
191
192 /* Append little-endian CRC32 and encrypt it to produce ICV */
193 #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
194 crc = ~crc32_le(~0, pos, len);
195 #else
196 crc = ~ether_crc_le(len, pos);
197 #endif
198 icv = skb_put(skb, 4);
199 icv[0] = crc;
200 icv[1] = crc >> 8;
201 icv[2] = crc >> 16;
202 icv[3] = crc >> 24;
203
204 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,24))
205 sg.page = virt_to_page(pos);
206 sg.offset = offset_in_page(pos);
207 sg.length = len + 4;
208 #else
209 sg_init_one(&sg, pos, len+4);
210 #endif
211 #if ( defined(BUILT_IN_CRYPTO) || ((LINUX_VERSION_CODE < KERNEL_VERSION(2,6,21)) && (!OPENSUSE_SLED)) )
212 crypto_cipher_setkey(wep->tfm, key, klen);
213 crypto_cipher_encrypt(wep->tfm, &sg, &sg, len + 4);
214 return 0;
215 #else
216 crypto_blkcipher_setkey(wep->tx_tfm, key, klen);
217 return crypto_blkcipher_encrypt(&desc, &sg, &sg, len + 4);
218 #endif
219 }
220
221 return 0;
222}
223
224
225/* Perform WEP decryption on given buffer. Buffer includes whole WEP part of
226 * the frame: IV (4 bytes), encrypted payload (including SNAP header),
227 * ICV (4 bytes). len includes both IV and ICV.
228 *
229 * Returns 0 if frame was decrypted successfully and ICV was correct and -1 on
230 * failure. If frame is OK, IV and ICV will be removed.
231 */
232static int prism2_wep_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
233{
234 struct prism2_wep_data *wep = priv;
235 u32 klen, plen;
236 u8 key[WEP_KEY_LEN + 3];
237 u8 keyidx, *pos;
238 cb_desc *tcb_desc = (cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE);
239 #if ( !defined(BUILT_IN_CRYPTO) && ((LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,21)) || (OPENSUSE_SLED)) )
240 struct blkcipher_desc desc = {.tfm = wep->rx_tfm};
241 #endif
242 u32 crc;
243 u8 icv[4];
244 struct scatterlist sg;
245 if (skb->len < hdr_len + 8)
246 return -1;
247
248 pos = skb->data + hdr_len;
249 key[0] = *pos++;
250 key[1] = *pos++;
251 key[2] = *pos++;
252 keyidx = *pos++ >> 6;
253 if (keyidx != wep->key_idx)
254 return -1;
255
256 klen = 3 + wep->key_len;
257
258 /* Copy rest of the WEP key (the secret part) */
259 memcpy(key + 3, wep->key, wep->key_len);
260
261 /* Apply RC4 to data and compute CRC32 over decrypted data */
262 plen = skb->len - hdr_len - 8;
263
264 if (!tcb_desc->bHwSec)
265 {
266 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,24))
267 sg.page = virt_to_page(pos);
268 sg.offset = offset_in_page(pos);
269 sg.length = plen + 4;
270 #else
271 sg_init_one(&sg, pos, plen+4);
272 #endif
273 #if ( defined(BUILT_IN_CRYPTO) || ((LINUX_VERSION_CODE < KERNEL_VERSION(2,6,21)) && (!OPENSUSE_SLED)) )
274 crypto_cipher_setkey(wep->tfm, key, klen);
275 crypto_cipher_decrypt(wep->tfm, &sg, &sg, plen + 4);
276 #else
277 crypto_blkcipher_setkey(wep->rx_tfm, key, klen);
278 if (crypto_blkcipher_decrypt(&desc, &sg, &sg, plen + 4))
279 return -7;
280 #endif
281 #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
282 crc = ~crc32_le(~0, pos, plen);
283 #else
284 crc = ~ether_crc_le(plen, pos);
285 #endif
286 icv[0] = crc;
287 icv[1] = crc >> 8;
288 icv[2] = crc >> 16;
289 icv[3] = crc >> 24;
290 if (memcmp(icv, pos + plen, 4) != 0) {
291 /* ICV mismatch - drop frame */
292 return -2;
293 }
294 }
295 /* Remove IV and ICV */
296 memmove(skb->data + 4, skb->data, hdr_len);
297 skb_pull(skb, 4);
298 skb_trim(skb, skb->len - 4);
299
300 return 0;
301}
302
303
304static int prism2_wep_set_key(void *key, int len, u8 *seq, void *priv)
305{
306 struct prism2_wep_data *wep = priv;
307
308 if (len < 0 || len > WEP_KEY_LEN)
309 return -1;
310
311 memcpy(wep->key, key, len);
312 wep->key_len = len;
313
314 return 0;
315}
316
317
318static int prism2_wep_get_key(void *key, int len, u8 *seq, void *priv)
319{
320 struct prism2_wep_data *wep = priv;
321
322 if (len < wep->key_len)
323 return -1;
324
325 memcpy(key, wep->key, wep->key_len);
326
327 return wep->key_len;
328}
329
330
331static char * prism2_wep_print_stats(char *p, void *priv)
332{
333 struct prism2_wep_data *wep = priv;
334 p += sprintf(p, "key[%d] alg=WEP len=%d\n",
335 wep->key_idx, wep->key_len);
336 return p;
337}
338
339
340static struct rtllib_crypto_ops rtllib_crypt_wep = {
341 .name = "WEP",
342 .init = prism2_wep_init,
343 .deinit = prism2_wep_deinit,
344 .encrypt_mpdu = prism2_wep_encrypt,
345 .decrypt_mpdu = prism2_wep_decrypt,
346 .encrypt_msdu = NULL,
347 .decrypt_msdu = NULL,
348 .set_key = prism2_wep_set_key,
349 .get_key = prism2_wep_get_key,
350 .print_stats = prism2_wep_print_stats,
351 .extra_prefix_len = 4, /* IV */
352 .extra_postfix_len = 4, /* ICV */
353 .owner = THIS_MODULE,
354};
355
356
357int __init rtllib_crypto_wep_init(void)
358{
359 return rtllib_register_crypto_ops(&rtllib_crypt_wep);
360}
361
362
363void __exit rtllib_crypto_wep_exit(void)
364{
365 rtllib_unregister_crypto_ops(&rtllib_crypt_wep);
366}
367
368void rtllib_wep_null(void)
369{
370 return;
371}
generated by cgit v1.2.2 (git 2.25.0) at 2024-10-21 20:38:53 -0400