release/src-rt-6.x.4708/bcmcrypto/wep.c

   1 /*
   2  *   wep.c - WEP functions
   3  *
   4  * Copyright (C) 2012, Broadcom Corporation
   5  * All Rights Reserved.
   6  *
   7  * This is UNPUBLISHED PROPRIETARY SOURCE CODE of Broadcom Corporation;
   8  * the contents of this file may not be disclosed to third parties, copied
   9  * or duplicated in any form, in whole or in part, without the prior
  10  * written permission of Broadcom Corporation.
  11  *
  12  * $Id: wep.c 358033 2012-09-20 23:57:22Z $
  13  */
  14
  15 #include <bcm_cfg.h>
  16 #include <typedefs.h>
  17
  18 /* include wl driver config file if this file is compiled for driver */
  19 #ifdef BCMDRIVER
  20 #include <osl.h>
  21 #else
  22 #include <string.h>
  23 #endif /* BCMDRIVER */
  24
  25 #include <bcmutils.h>
  26 #include <bcmcrypto/rc4.h>
  27 #include <bcmcrypto/wep.h>
  28 #include <proto/802.11.h>
  29
  30 /* WEP-encrypt a buffer */
  31 /* assumes a contiguous buffer, with IV prepended, and with enough space at
  32  * the end for the ICV
  33  */
  34 void
  35 BCMROMFN(wep_encrypt)(uint buf_len, uint8 *buf, uint sec_len, uint8 *sec_data)
  36 {
  37         uint8 key_data[16];
  38         uint32 ICV;
  39         rc4_ks_t ks;
  40         uint8 *body = buf + DOT11_IV_LEN;
  41         uint body_len = buf_len - (DOT11_IV_LEN + DOT11_ICV_LEN);
  42         uint8 *picv = body + body_len;
  43
  44         memcpy(key_data, buf, 3);
  45         memcpy(&key_data[3], sec_data, sec_len);
  46
  47         prepare_key(key_data, sec_len + 3, &ks);
  48
  49         /* append ICV */
  50         ICV = ~hndcrc32(body, body_len, CRC32_INIT_VALUE);
  51         picv[0] = ICV & 0xff;
  52         picv[1] = (ICV >> 8) & 0xff;
  53         picv[2] = (ICV >> 16) & 0xff;
  54         picv[3] = (ICV >> 24) & 0xff;
  55
  56         rc4(body, body_len + DOT11_ICV_LEN, &ks);
  57 }
  58
  59 /* WEP-decrypt
  60  * Assumes a contigous buffer, with IV prepended.
  61  * Returns TRUE if ICV check passes, FALSE otherwise
  62  *
  63  */
  64 bool
  65 BCMROMFN(wep_decrypt)(uint buf_len, uint8 *buf, uint sec_len, uint8 *sec_data)
  66 {
  67         uint8 key_data[16];
  68         rc4_ks_t ks;
  69
  70         memcpy(key_data, buf, 3);
  71         memcpy(&key_data[3], sec_data, sec_len);
  72
  73         prepare_key(key_data, sec_len + 3, &ks);
  74
  75         rc4(buf + DOT11_IV_LEN, buf_len - DOT11_IV_LEN, &ks);
  76
  77         return (hndcrc32(buf + DOT11_IV_LEN, buf_len - DOT11_IV_LEN, CRC32_INIT_VALUE) ==
  78                 CRC32_GOOD_VALUE);
  79 }