1 // SPDX-License-Identifier: (GPL-2.0 OR MPL-1.1)
2 /* src/p80211/p80211wep.c
4 * WEP encode/decode for P80211.
6 * Copyright (C) 2002 AbsoluteValue Systems, Inc. All Rights Reserved.
7 * --------------------------------------------------------------------
11 * The contents of this file are subject to the Mozilla Public
12 * License Version 1.1 (the "License"); you may not use this file
13 * except in compliance with the License. You may obtain a copy of
14 * the License at http://www.mozilla.org/MPL/
16 * Software distributed under the License is distributed on an "AS
17 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
18 * implied. See the License for the specific language governing
19 * rights and limitations under the License.
21 * Alternatively, the contents of this file may be used under the
22 * terms of the GNU Public License version 2 (the "GPL"), in which
23 * case the provisions of the GPL are applicable instead of the
24 * above. If you wish to allow the use of your version of this file
25 * only under the terms of the GPL and not to allow others to use
26 * your version of this file under the MPL, indicate your decision
27 * by deleting the provisions above and replace them with the notice
28 * and other provisions required by the GPL. If you do not delete
29 * the provisions above, a recipient may use your version of this
30 * file under either the MPL or the GPL.
32 * --------------------------------------------------------------------
34 * Inquiries regarding the linux-wlan Open Source project can be
37 * AbsoluteValue Systems Inc.
39 * http://www.linux-wlan.com
41 * --------------------------------------------------------------------
43 * Portions of the development of this software were funded by
44 * Intersil Corporation as part of PRISM(R) chipset product development.
46 * --------------------------------------------------------------------
49 /*================================================================*/
52 #include <linux/netdevice.h>
53 #include <linux/wireless.h>
54 #include <linux/random.h>
55 #include <linux/kernel.h>
56 #include "p80211hdr.h"
57 #include "p80211types.h"
58 #include "p80211msg.h"
59 #include "p80211conv.h"
60 #include "p80211netdev.h"
62 #define WEP_KEY(x) (((x) & 0xC0) >> 6)
64 static const u32 wep_crc32_table[256] = {
65 0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
66 0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
67 0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
68 0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
69 0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
70 0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
71 0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
72 0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
73 0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
74 0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
75 0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
76 0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
77 0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
78 0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
79 0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
80 0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
81 0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
82 0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
83 0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
84 0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
85 0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
86 0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
87 0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
88 0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
89 0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
90 0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
91 0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
92 0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
93 0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
94 0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
95 0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
96 0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
97 0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
98 0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
99 0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
100 0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
101 0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
102 0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
103 0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
104 0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
105 0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
106 0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
107 0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
108 0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
109 0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
110 0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
111 0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
112 0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
113 0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
114 0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
115 0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
119 /* keylen in bytes! */
121 int wep_change_key(struct wlandevice *wlandev, int keynum, u8 *key, int keylen)
125 if (keylen >= MAX_KEYLEN)
131 if (keynum >= NUM_WEPKEYS)
134 wlandev->wep_keylens[keynum] = keylen;
135 memcpy(wlandev->wep_keys[keynum], key, keylen);
141 * 4-byte IV at start of buffer, 4-byte ICV at end of buffer.
142 * if successful, buf start is payload begin, length -= 8;
144 int wep_decrypt(struct wlandevice *wlandev, u8 *buf, u32 len, int key_override,
147 u32 i, j, k, crc, keylen;
148 u8 s[256], key[64], c_crc[4];
151 /* Needs to be at least 8 bytes of payload */
155 /* initialize the first bytes of the key from the IV */
159 keyidx = WEP_KEY(iv[3]);
161 if (key_override >= 0)
162 keyidx = key_override;
164 if (keyidx >= NUM_WEPKEYS)
167 keylen = wlandev->wep_keylens[keyidx];
172 /* copy the rest of the key over from the designated key */
173 memcpy(key + 3, wlandev->wep_keys[keyidx], keylen);
175 keylen += 3; /* add in IV bytes */
177 /* set up the RC4 state */
178 for (i = 0; i < 256; i++)
181 for (i = 0; i < 256; i++) {
182 j = (j + s[i] + key[i % keylen]) & 0xff;
186 /* Apply the RC4 to the data, update the CRC32 */
190 for (k = 0; k < len; k++) {
192 j = (j + s[i]) & 0xff;
194 buf[k] ^= s[(s[i] + s[j]) & 0xff];
195 crc = wep_crc32_table[(crc ^ buf[k]) & 0xff] ^ (crc >> 8);
199 /* now let's check the crc */
202 c_crc[2] = crc >> 16;
203 c_crc[3] = crc >> 24;
205 for (k = 0; k < 4; k++) {
207 j = (j + s[i]) & 0xff;
209 if ((c_crc[k] ^ s[(s[i] + s[j]) & 0xff]) != icv[k])
210 return -(4 | (k << 4)); /* ICV mismatch */
216 /* encrypts in-place. */
217 int wep_encrypt(struct wlandevice *wlandev, u8 *buf,
218 u8 *dst, u32 len, int keynum, u8 *iv, u8 *icv)
220 u32 i, j, k, crc, keylen;
223 /* no point in WEPping an empty frame */
227 /* we need to have a real key.. */
228 if (keynum >= NUM_WEPKEYS)
230 keylen = wlandev->wep_keylens[keynum];
234 /* use a random IV. And skip known weak ones. */
235 get_random_bytes(iv, 3);
236 while ((iv[1] == 0xff) && (iv[0] >= 3) && (iv[0] < keylen))
237 get_random_bytes(iv, 3);
239 iv[3] = (keynum & 0x03) << 6;
245 /* copy the rest of the key over from the designated key */
246 memcpy(key + 3, wlandev->wep_keys[keynum], keylen);
248 keylen += 3; /* add in IV bytes */
250 /* set up the RC4 state */
251 for (i = 0; i < 256; i++)
254 for (i = 0; i < 256; i++) {
255 j = (j + s[i] + key[i % keylen]) & 0xff;
259 /* Update CRC32 then apply RC4 to the data */
263 for (k = 0; k < len; k++) {
264 crc = wep_crc32_table[(crc ^ buf[k]) & 0xff] ^ (crc >> 8);
266 j = (j + s[i]) & 0xff;
268 dst[k] = buf[k] ^ s[(s[i] + s[j]) & 0xff];
272 /* now let's encrypt the crc */
278 for (k = 0; k < 4; k++) {
280 j = (j + s[i]) & 0xff;
282 icv[k] ^= s[(s[i] + s[j]) & 0xff];