| /* src/p80211/p80211wep.c |
| * |
| * WEP encode/decode for P80211. |
| * |
| * Copyright (C) 2002 AbsoluteValue Systems, Inc. All Rights Reserved. |
| * -------------------------------------------------------------------- |
| * |
| * linux-wlan |
| * |
| * The contents of this file are subject to the Mozilla Public |
| * License Version 1.1 (the "License"); you may not use this file |
| * except in compliance with the License. You may obtain a copy of |
| * the License at http://www.mozilla.org/MPL/ |
| * |
| * Software distributed under the License is distributed on an "AS |
| * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or |
| * implied. See the License for the specific language governing |
| * rights and limitations under the License. |
| * |
| * Alternatively, the contents of this file may be used under the |
| * terms of the GNU Public License version 2 (the "GPL"), in which |
| * case the provisions of the GPL are applicable instead of the |
| * above. If you wish to allow the use of your version of this file |
| * only under the terms of the GPL and not to allow others to use |
| * your version of this file under the MPL, indicate your decision |
| * by deleting the provisions above and replace them with the notice |
| * and other provisions required by the GPL. If you do not delete |
| * the provisions above, a recipient may use your version of this |
| * file under either the MPL or the GPL. |
| * |
| * -------------------------------------------------------------------- |
| * |
| * Inquiries regarding the linux-wlan Open Source project can be |
| * made directly to: |
| * |
| * AbsoluteValue Systems Inc. |
| * info@linux-wlan.com |
| * http://www.linux-wlan.com |
| * |
| * -------------------------------------------------------------------- |
| * |
| * Portions of the development of this software were funded by |
| * Intersil Corporation as part of PRISM(R) chipset product development. |
| * |
| * -------------------------------------------------------------------- |
| */ |
| |
| /*================================================================*/ |
| /* System Includes */ |
| |
| #include <linux/netdevice.h> |
| #include <linux/wireless.h> |
| #include <linux/random.h> |
| #include <linux/kernel.h> |
| #include "p80211hdr.h" |
| #include "p80211types.h" |
| #include "p80211msg.h" |
| #include "p80211conv.h" |
| #include "p80211netdev.h" |
| |
| #define WEP_KEY(x) (((x) & 0xC0) >> 6) |
| |
| static const u32 wep_crc32_table[256] = { |
| 0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L, |
| 0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L, |
| 0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L, |
| 0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL, |
| 0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L, |
| 0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L, |
| 0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L, |
| 0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL, |
| 0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L, |
| 0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL, |
| 0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L, |
| 0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L, |
| 0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L, |
| 0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL, |
| 0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL, |
| 0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L, |
| 0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL, |
| 0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L, |
| 0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L, |
| 0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L, |
| 0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL, |
| 0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L, |
| 0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L, |
| 0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL, |
| 0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L, |
| 0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L, |
| 0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L, |
| 0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L, |
| 0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L, |
| 0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL, |
| 0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL, |
| 0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L, |
| 0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L, |
| 0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL, |
| 0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL, |
| 0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L, |
| 0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL, |
| 0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L, |
| 0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL, |
| 0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L, |
| 0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL, |
| 0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L, |
| 0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L, |
| 0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL, |
| 0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L, |
| 0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L, |
| 0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L, |
| 0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L, |
| 0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L, |
| 0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L, |
| 0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL, |
| 0x2d02ef8dL |
| }; |
| |
| /* keylen in bytes! */ |
| |
| int wep_change_key(struct wlandevice *wlandev, int keynum, u8 *key, int keylen) |
| { |
| if (keylen < 0) |
| return -1; |
| if (keylen >= MAX_KEYLEN) |
| return -1; |
| if (!key) |
| return -1; |
| if (keynum < 0) |
| return -1; |
| if (keynum >= NUM_WEPKEYS) |
| return -1; |
| |
| wlandev->wep_keylens[keynum] = keylen; |
| memcpy(wlandev->wep_keys[keynum], key, keylen); |
| |
| return 0; |
| } |
| |
| /* |
| * 4-byte IV at start of buffer, 4-byte ICV at end of buffer. |
| * if successful, buf start is payload begin, length -= 8; |
| */ |
| int wep_decrypt(struct wlandevice *wlandev, u8 *buf, u32 len, int key_override, |
| u8 *iv, u8 *icv) |
| { |
| u32 i, j, k, crc, keylen; |
| u8 s[256], key[64], c_crc[4]; |
| u8 keyidx; |
| |
| /* Needs to be at least 8 bytes of payload */ |
| if (len <= 0) |
| return -1; |
| |
| /* initialize the first bytes of the key from the IV */ |
| key[0] = iv[0]; |
| key[1] = iv[1]; |
| key[2] = iv[2]; |
| keyidx = WEP_KEY(iv[3]); |
| |
| if (key_override >= 0) |
| keyidx = key_override; |
| |
| if (keyidx >= NUM_WEPKEYS) |
| return -2; |
| |
| keylen = wlandev->wep_keylens[keyidx]; |
| |
| if (keylen == 0) |
| return -3; |
| |
| /* copy the rest of the key over from the designated key */ |
| memcpy(key + 3, wlandev->wep_keys[keyidx], keylen); |
| |
| keylen += 3; /* add in IV bytes */ |
| |
| /* set up the RC4 state */ |
| for (i = 0; i < 256; i++) |
| s[i] = i; |
| j = 0; |
| for (i = 0; i < 256; i++) { |
| j = (j + s[i] + key[i % keylen]) & 0xff; |
| swap(i, j); |
| } |
| |
| /* Apply the RC4 to the data, update the CRC32 */ |
| crc = ~0; |
| i = 0; |
| j = 0; |
| for (k = 0; k < len; k++) { |
| i = (i + 1) & 0xff; |
| j = (j + s[i]) & 0xff; |
| swap(i, j); |
| buf[k] ^= s[(s[i] + s[j]) & 0xff]; |
| crc = wep_crc32_table[(crc ^ buf[k]) & 0xff] ^ (crc >> 8); |
| } |
| crc = ~crc; |
| |
| /* now let's check the crc */ |
| c_crc[0] = crc; |
| c_crc[1] = crc >> 8; |
| c_crc[2] = crc >> 16; |
| c_crc[3] = crc >> 24; |
| |
| for (k = 0; k < 4; k++) { |
| i = (i + 1) & 0xff; |
| j = (j + s[i]) & 0xff; |
| swap(i, j); |
| if ((c_crc[k] ^ s[(s[i] + s[j]) & 0xff]) != icv[k]) |
| return -(4 | (k << 4)); /* ICV mismatch */ |
| } |
| |
| return 0; |
| } |
| |
| /* encrypts in-place. */ |
| int wep_encrypt(struct wlandevice *wlandev, u8 *buf, |
| u8 *dst, u32 len, int keynum, u8 *iv, u8 *icv) |
| { |
| u32 i, j, k, crc, keylen; |
| u8 s[256], key[64]; |
| |
| /* no point in WEPping an empty frame */ |
| if (len <= 0) |
| return -1; |
| |
| /* we need to have a real key.. */ |
| if (keynum >= NUM_WEPKEYS) |
| return -2; |
| keylen = wlandev->wep_keylens[keynum]; |
| if (keylen <= 0) |
| return -3; |
| |
| /* use a random IV. And skip known weak ones. */ |
| get_random_bytes(iv, 3); |
| while ((iv[1] == 0xff) && (iv[0] >= 3) && (iv[0] < keylen)) |
| get_random_bytes(iv, 3); |
| |
| iv[3] = (keynum & 0x03) << 6; |
| |
| key[0] = iv[0]; |
| key[1] = iv[1]; |
| key[2] = iv[2]; |
| |
| /* copy the rest of the key over from the designated key */ |
| memcpy(key + 3, wlandev->wep_keys[keynum], keylen); |
| |
| keylen += 3; /* add in IV bytes */ |
| |
| /* set up the RC4 state */ |
| for (i = 0; i < 256; i++) |
| s[i] = i; |
| j = 0; |
| for (i = 0; i < 256; i++) { |
| j = (j + s[i] + key[i % keylen]) & 0xff; |
| swap(i, j); |
| } |
| |
| /* Update CRC32 then apply RC4 to the data */ |
| crc = ~0; |
| i = 0; |
| j = 0; |
| for (k = 0; k < len; k++) { |
| crc = wep_crc32_table[(crc ^ buf[k]) & 0xff] ^ (crc >> 8); |
| i = (i + 1) & 0xff; |
| j = (j + s[i]) & 0xff; |
| swap(i, j); |
| dst[k] = buf[k] ^ s[(s[i] + s[j]) & 0xff]; |
| } |
| crc = ~crc; |
| |
| /* now let's encrypt the crc */ |
| icv[0] = crc; |
| icv[1] = crc >> 8; |
| icv[2] = crc >> 16; |
| icv[3] = crc >> 24; |
| |
| for (k = 0; k < 4; k++) { |
| i = (i + 1) & 0xff; |
| j = (j + s[i]) & 0xff; |
| swap(i, j); |
| icv[k] ^= s[(s[i] + s[j]) & 0xff]; |
| } |
| |
| return 0; |
| } |