linux-imx

/*

 * lib80211 crypt: host-based WEP encryption implementation for lib80211

 *

 * Copyright (c) 2002-2004, Jouni Malinen <j@w1.fi>

 * Copyright (c) 2008, John W. Linville <linville@tuxdriver.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation. See README and COPYING for

 * more details.

 */

​

#include <linux/err.h>

#include <linux/module.h>

#include <linux/init.h>

#include <linux/slab.h>

#include <linux/random.h>

#include <linux/scatterlist.h>

#include <linux/skbuff.h>

#include <linux/mm.h>

#include <asm/string.h>

​

#include <net/lib80211.h>

​

#include <linux/crypto.h>

#include <linux/crc32.h>

​

MODULE_AUTHOR("Jouni Malinen");

MODULE_DESCRIPTION("lib80211 crypt: WEP");

MODULE_LICENSE("GPL");

​

struct lib80211_wep_data {

    u32 iv;

#define WEP_KEY_LEN 13

    u8 key[WEP_KEY_LEN + 1];

    u8 key_len;

    u8 key_idx;

    struct crypto_cipher *tx_tfm;

    struct crypto_cipher *rx_tfm;

};

​

static void *lib80211_wep_init(int keyidx)

{

    struct lib80211_wep_data *priv;

​

    priv = kzalloc(sizeof(*priv), GFP_ATOMIC);

    if (priv == NULL)

        goto fail;

    priv->key_idx = keyidx;

​

    priv->tx_tfm = crypto_alloc_cipher("arc4", 0, 0);

    if (IS_ERR(priv->tx_tfm)) {

        priv->tx_tfm = NULL;

        goto fail;

    }

​

    priv->rx_tfm = crypto_alloc_cipher("arc4", 0, 0);

    if (IS_ERR(priv->rx_tfm)) {

        priv->rx_tfm = NULL;

        goto fail;

    }

    /* start WEP IV from a random value */

    get_random_bytes(&priv->iv, 4);

​

    return priv;

​

      fail:

    if (priv) {

        crypto_free_cipher(priv->tx_tfm);

        crypto_free_cipher(priv->rx_tfm);

        kfree(priv);

    }

    return NULL;

}

​

static void lib80211_wep_deinit(void *priv)

{

    struct lib80211_wep_data *_priv = priv;

    if (_priv) {

        crypto_free_cipher(_priv->tx_tfm);

        crypto_free_cipher(_priv->rx_tfm);

    }

    kfree(priv);

}

​

/* Add WEP IV/key info to a frame that has at least 4 bytes of headroom */

static int lib80211_wep_build_iv(struct sk_buff *skb, int hdr_len,

                   u8 *key, int keylen, void *priv)

{

    struct lib80211_wep_data *wep = priv;

    u32 klen;

    u8 *pos;