[linux-2.6-block.git] / net / mac80211 / wep.c

/*
 * Software WEP encryption implementation
 * Copyright 2002, Jouni Malinen <jkmaline@cc.hut.fi>
 * Copyright 2003, Instant802 Networks, Inc.
 *
 * 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.
 */

#include <linux/netdevice.h>
#include <linux/types.h>
#include <linux/random.h>
#include <linux/compiler.h>
#include <linux/crc32.h>
#include <linux/crypto.h>
#include <linux/err.h>
#include <linux/mm.h>
#include <linux/scatterlist.h>
#include <asm/unaligned.h>

#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "wep.h"


int ieee80211_wep_init(struct ieee80211_local *local)
{
	/* start WEP IV from a random value */
	get_random_bytes(&local->wep_iv, WEP_IV_LEN);

	local->wep_tx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0,
						CRYPTO_ALG_ASYNC);
	if (IS_ERR(local->wep_tx_tfm))
		return PTR_ERR(local->wep_tx_tfm);

	local->wep_rx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0,
						CRYPTO_ALG_ASYNC);
	if (IS_ERR(local->wep_rx_tfm)) {
		crypto_free_blkcipher(local->wep_tx_tfm);
		return PTR_ERR(local->wep_rx_tfm);
	}

	return 0;
}

void ieee80211_wep_free(struct ieee80211_local *local)
{
	crypto_free_blkcipher(local->wep_tx_tfm);
	crypto_free_blkcipher(local->wep_rx_tfm);
}

static inline bool ieee80211_wep_weak_iv(u32 iv, int keylen)
{
	/*
	 * Fluhrer, Mantin, and Shamir have reported weaknesses in the
	 * key scheduling algorithm of RC4. At least IVs (KeyByte + 3,
	 * 0xff, N) can be used to speedup attacks, so avoid using them.
	 */
	if ((iv & 0xff00) == 0xff00) {
		u8 B = (iv >> 16) & 0xff;
		if (B >= 3 && B < 3 + keylen)
			return true;
	}
	return false;
}


static void ieee80211_wep_get_iv(struct ieee80211_local *local,
				 int keylen, int keyidx, u8 *iv)
{
	local->wep_iv++;
	if (ieee80211_wep_weak_iv(local->wep_iv, keylen))
		local->wep_iv += 0x0100;

	if (!iv)
		return;

	*iv++ = (local->wep_iv >> 16) & 0xff;
	*iv++ = (local->wep_iv >> 8) & 0xff;
	*iv++ = local->wep_iv & 0xff;
	*iv++ = keyidx << 6;
}


static u8 *ieee80211_wep_add_iv(struct ieee80211_local *local,
				struct sk_buff *skb,
				int keylen, int keyidx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
	unsigned int hdrlen;
	u8 *newhdr;

	hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);

	if (WARN_ON(skb_tailroom(skb) < WEP_ICV_LEN ||
		    skb_headroom(skb) < WEP_IV_LEN))
		return NULL;

	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	newhdr = skb_push(skb, WEP_IV_LEN);
	memmove(newhdr, newhdr + WEP_IV_LEN, hdrlen);
	ieee80211_wep_get_iv(local, keylen, keyidx, newhdr + hdrlen);
	return newhdr + hdrlen;
}


static void ieee80211_wep_remove_iv(struct ieee80211_local *local,
				    struct sk_buff *skb,
				    struct ieee80211_key *key)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
	unsigned int hdrlen;

	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	memmove(skb->data + WEP_IV_LEN, skb->data, hdrlen);
	skb_pull(skb, WEP_IV_LEN);
}


/* Perform WEP encryption using given key. data buffer must have tailroom
 * for 4-byte ICV. data_len must not include this ICV. Note: this function
 * does _not_ add IV. data = RC4(data | CRC32(data)) */
void ieee80211_wep_encrypt_data(struct crypto_blkcipher *tfm, u8 *rc4key,
				size_t klen, u8 *data, size_t data_len)
{
	struct blkcipher_desc desc = { .tfm = tfm };
	struct scatterlist sg;
	__le32 icv;

	icv = cpu_to_le32(~crc32_le(~0, data, data_len));
	put_unaligned(icv, (__le32 *)(data + data_len));

	crypto_blkcipher_setkey(tfm, rc4key, klen);
	sg_init_one(&sg, data, data_len + WEP_ICV_LEN);
	crypto_blkcipher_encrypt(&desc, &sg, &sg, sg.length);
}


/* Perform WEP encryption on given skb. 4 bytes of extra space (IV) in the
 * beginning of the buffer 4 bytes of extra space (ICV) in the end of the
 * buffer will be added. Both IV and ICV will be transmitted, so the
 * payload length increases with 8 bytes.
 *
 * WEP frame payload: IV + TX key idx, RC4(data), ICV = RC4(CRC32(data))
 */
int ieee80211_wep_encrypt(struct ieee80211_local *local,
			  struct sk_buff *skb,
			  const u8 *key, int keylen, int keyidx)
{
	u8 *iv;
	size_t len;
	u8 rc4key[3 + WLAN_KEY_LEN_WEP104];

	iv = ieee80211_wep_add_iv(local, skb, keylen, keyidx);
	if (!iv)
		return -1;

	len = skb->len - (iv + WEP_IV_LEN - skb->data);

	/* Prepend 24-bit IV to RC4 key */
	memcpy(rc4key, iv, 3);

	/* Copy rest of the WEP key (the secret part) */
	memcpy(rc4key + 3, key, keylen);

	/* Add room for ICV */
	skb_put(skb, WEP_ICV_LEN);

	ieee80211_wep_encrypt_data(local->wep_tx_tfm, rc4key, keylen + 3,
				   iv + WEP_IV_LEN, len);

	return 0;
}


/* Perform WEP decryption using given key. data buffer includes encrypted
 * payload, including 4-byte ICV, but _not_ IV. data_len must not include ICV.
 * Return 0 on success and -1 on ICV mismatch. */
int ieee80211_wep_decrypt_data(struct crypto_blkcipher *tfm, u8 *rc4key,
			       size_t klen, u8 *data, size_t data_len)
{
	struct blkcipher_desc desc = { .tfm = tfm };
	struct scatterlist sg;
	__le32 crc;

	crypto_blkcipher_setkey(tfm, rc4key, klen);
	sg_init_one(&sg, data, data_len + WEP_ICV_LEN);
	crypto_blkcipher_decrypt(&desc, &sg, &sg, sg.length);

	crc = cpu_to_le32(~crc32_le(~0, data, data_len));
	if (memcmp(&crc, data + data_len, WEP_ICV_LEN) != 0)
		/* ICV mismatch */
		return -1;

	return 0;
}


/* Perform WEP decryption on given skb. Buffer includes whole WEP part of
 * the frame: IV (4 bytes), encrypted payload (including SNAP header),
 * ICV (4 bytes). skb->len includes both IV and ICV.
 *
 * Returns 0 if frame was decrypted successfully and ICV was correct and -1 on
 * failure. If frame is OK, IV and ICV will be removed, i.e., decrypted payload
 * is moved to the beginning of the skb and skb length will be reduced.
 */
static int ieee80211_wep_decrypt(struct ieee80211_local *local,
				 struct sk_buff *skb,
				 struct ieee80211_key *key)
{
	u32 klen;
	u8 *rc4key;
	u8 keyidx;
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
	unsigned int hdrlen;
	size_t len;
	int ret = 0;

	if (!ieee80211_has_protected(hdr->frame_control))
		return -1;

	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	if (skb->len < hdrlen + WEP_IV_LEN + WEP_ICV_LEN)
		return -1;

	len = skb->len - hdrlen - WEP_IV_LEN - WEP_ICV_LEN;

	keyidx = skb->data[hdrlen + 3] >> 6;

	if (!key || keyidx != key->conf.keyidx || key->conf.alg != ALG_WEP)
		return -1;

	klen = 3 + key->conf.keylen;

	rc4key = kmalloc(klen, GFP_ATOMIC);
	if (!rc4key)
		return -1;

	/* Prepend 24-bit IV to RC4 key */
	memcpy(rc4key, skb->data + hdrlen, 3);

	/* Copy rest of the WEP key (the secret part) */
	memcpy(rc4key + 3, key->conf.key, key->conf.keylen);

	if (ieee80211_wep_decrypt_data(local->wep_rx_tfm, rc4key, klen,
				       skb->data + hdrlen + WEP_IV_LEN,
				       len))
		ret = -1;

	kfree(rc4key);

	/* Trim ICV */
	skb_trim(skb, skb->len - WEP_ICV_LEN);

	/* Remove IV */
	memmove(skb->data + WEP_IV_LEN, skb->data, hdrlen);
	skb_pull(skb, WEP_IV_LEN);

	return ret;
}


bool ieee80211_wep_is_weak_iv(struct sk_buff *skb, struct ieee80211_key *key)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
	unsigned int hdrlen;
	u8 *ivpos;
	u32 iv;

	if (!ieee80211_has_protected(hdr->frame_control))
		return false;

	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	ivpos = skb->data + hdrlen;
	iv = (ivpos[0] << 16) | (ivpos[1] << 8) | ivpos[2];

	return ieee80211_wep_weak_iv(iv, key->conf.keylen);
}

ieee80211_rx_result
ieee80211_crypto_wep_decrypt(struct ieee80211_rx_data *rx)
{
	struct sk_buff *skb = rx->skb;
	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;

	if (!ieee80211_is_data(hdr->frame_control) &&
	    !ieee80211_is_auth(hdr->frame_control))
		return RX_CONTINUE;

	if (!(status->flag & RX_FLAG_DECRYPTED)) {
		if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key))
			return RX_DROP_UNUSABLE;
	} else if (!(status->flag & RX_FLAG_IV_STRIPPED)) {
		ieee80211_wep_remove_iv(rx->local, rx->skb, rx->key);
		/* remove ICV */
		skb_trim(rx->skb, rx->skb->len - WEP_ICV_LEN);
	}

	return RX_CONTINUE;
}

static int wep_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
{
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);

	if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) {
		if (ieee80211_wep_encrypt(tx->local, skb, tx->key->conf.key,
					  tx->key->conf.keylen,
					  tx->key->conf.keyidx))
			return -1;
	} else {
		info->control.hw_key = &tx->key->conf;
		if (tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) {
			if (!ieee80211_wep_add_iv(tx->local, skb,
						  tx->key->conf.keylen,
						  tx->key->conf.keyidx))
				return -1;
		}
	}
	return 0;
}

ieee80211_tx_result
ieee80211_crypto_wep_encrypt(struct ieee80211_tx_data *tx)
{
	struct sk_buff *skb;

	ieee80211_tx_set_protected(tx);

	skb = tx->skb;
	do {
		if (wep_encrypt_skb(tx, skb) < 0) {
			I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
			return TX_DROP;
		}
	} while ((skb = skb->next));

	return TX_CONTINUE;
}
Commit	Line	Data
f0706e82 JB	1	/*
	2	* Software WEP encryption implementation
	3	* Copyright 2002, Jouni Malinen <jkmaline@cc.hut.fi>
	4	* Copyright 2003, Instant802 Networks, Inc.
	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.
	9	*/
	10
	11	#include <linux/netdevice.h>
	12	#include <linux/types.h>
	13	#include <linux/random.h>
	14	#include <linux/compiler.h>
	15	#include <linux/crc32.h>
	16	#include <linux/crypto.h>
	17	#include <linux/err.h>
	18	#include <linux/mm.h>
11763609	19	#include <linux/scatterlist.h>
860c6e6a	20	#include <asm/unaligned.h>
f0706e82 JB	21
	22	#include <net/mac80211.h>
	23	#include "ieee80211_i.h"
	24	#include "wep.h"
	25
	26
	27	int ieee80211_wep_init(struct ieee80211_local *local)
	28	{
	29	/* start WEP IV from a random value */
	30	get_random_bytes(&local->wep_iv, WEP_IV_LEN);
	31
	32	local->wep_tx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0,
	33	CRYPTO_ALG_ASYNC);
	34	if (IS_ERR(local->wep_tx_tfm))
023a04be	35	return PTR_ERR(local->wep_tx_tfm);
f0706e82 JB	36
	37	local->wep_rx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0,
	38	CRYPTO_ALG_ASYNC);
	39	if (IS_ERR(local->wep_rx_tfm)) {
	40	crypto_free_blkcipher(local->wep_tx_tfm);
023a04be	41	return PTR_ERR(local->wep_rx_tfm);
f0706e82 JB	42	}
	43
	44	return 0;
	45	}
	46
	47	void ieee80211_wep_free(struct ieee80211_local *local)
	48	{
	49	crypto_free_blkcipher(local->wep_tx_tfm);
	50	crypto_free_blkcipher(local->wep_rx_tfm);
	51	}
	52
c6a1fa12	53	static inline bool ieee80211_wep_weak_iv(u32 iv, int keylen)
f0706e82	54	{
c6a1fa12 JB	55	/*
c6a1fa12 JB	56	* Fluhrer, Mantin, and Shamir have reported weaknesses in the
f0706e82	57	* key scheduling algorithm of RC4. At least IVs (KeyByte + 3,
c6a1fa12 JB	58	* 0xff, N) can be used to speedup attacks, so avoid using them.
c6a1fa12 JB	59	*/
f0706e82 JB	60	if ((iv & 0xff00) == 0xff00) {
	61	u8 B = (iv >> 16) & 0xff;
	62	if (B >= 3 && B < 3 + keylen)
c6a1fa12	63	return true;
f0706e82	64	}
c6a1fa12	65	return false;
f0706e82 JB	66	}
	67
	68
4f0d18e2	69	static void ieee80211_wep_get_iv(struct ieee80211_local *local,
c9cf0122	70	int keylen, int keyidx, u8 *iv)
f0706e82 JB	71	{
f0706e82 JB	72	local->wep_iv++;
c9cf0122	73	if (ieee80211_wep_weak_iv(local->wep_iv, keylen))
f0706e82 JB	74	local->wep_iv += 0x0100;
	75
	76	if (!iv)
	77	return;
	78
	79	*iv++ = (local->wep_iv >> 16) & 0xff;
	80	*iv++ = (local->wep_iv >> 8) & 0xff;
	81	*iv++ = local->wep_iv & 0xff;
c9cf0122	82	*iv++ = keyidx << 6;
f0706e82 JB	83	}
	84
	85
6a22a59d JB	86	static u8 ieee80211_wep_add_iv(struct ieee80211_local local,
6a22a59d JB	87	struct sk_buff *skb,
c9cf0122	88	int keylen, int keyidx)
f0706e82	89	{
70217d7f HH	90	struct ieee80211_hdr hdr = (struct ieee80211_hdr )skb->data;
70217d7f HH	91	unsigned int hdrlen;
f0706e82 JB	92	u8 *newhdr;
f0706e82 JB	93
70217d7f	94	hdr->frame_control \|= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
f0706e82	95
23c0752a JB	96	if (WARN_ON(skb_tailroom(skb) < WEP_ICV_LEN \|\|
	97	skb_headroom(skb) < WEP_IV_LEN))
	98	return NULL;
f0706e82	99
70217d7f	100	hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82 JB	101	newhdr = skb_push(skb, WEP_IV_LEN);
f0706e82 JB	102	memmove(newhdr, newhdr + WEP_IV_LEN, hdrlen);
c9cf0122	103	ieee80211_wep_get_iv(local, keylen, keyidx, newhdr + hdrlen);
f0706e82 JB	104	return newhdr + hdrlen;
	105	}
	106
	107
4f0d18e2 JB	108	static void ieee80211_wep_remove_iv(struct ieee80211_local *local,
	109	struct sk_buff *skb,
	110	struct ieee80211_key *key)
f0706e82	111	{
70217d7f HH	112	struct ieee80211_hdr hdr = (struct ieee80211_hdr )skb->data;
70217d7f HH	113	unsigned int hdrlen;
f0706e82	114
70217d7f	115	hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82 JB	116	memmove(skb->data + WEP_IV_LEN, skb->data, hdrlen);
	117	skb_pull(skb, WEP_IV_LEN);
	118	}
	119
	120
	121	/* Perform WEP encryption using given key. data buffer must have tailroom
	122	* for 4-byte ICV. data_len must not include this ICV. Note: this function
	123	* does _not_ add IV. data = RC4(data \| CRC32(data)) */
	124	void ieee80211_wep_encrypt_data(struct crypto_blkcipher tfm, u8 rc4key,
	125	size_t klen, u8 *data, size_t data_len)
	126	{
	127	struct blkcipher_desc desc = { .tfm = tfm };
	128	struct scatterlist sg;
860c6e6a	129	__le32 icv;
f0706e82	130
860c6e6a IK	131	icv = cpu_to_le32(~crc32_le(~0, data, data_len));
860c6e6a IK	132	put_unaligned(icv, (__le32 *)(data + data_len));
f0706e82 JB	133
f0706e82 JB	134	crypto_blkcipher_setkey(tfm, rc4key, klen);
fa05f128	135	sg_init_one(&sg, data, data_len + WEP_ICV_LEN);
f0706e82 JB	136	crypto_blkcipher_encrypt(&desc, &sg, &sg, sg.length);
	137	}
	138
	139
	140	/* Perform WEP encryption on given skb. 4 bytes of extra space (IV) in the
	141	* beginning of the buffer 4 bytes of extra space (ICV) in the end of the
	142	* buffer will be added. Both IV and ICV will be transmitted, so the
	143	* payload length increases with 8 bytes.
	144	*
	145	* WEP frame payload: IV + TX key idx, RC4(data), ICV = RC4(CRC32(data))
	146	*/
fffd0934 JB	147	int ieee80211_wep_encrypt(struct ieee80211_local *local,
	148	struct sk_buff *skb,
	149	const u8 *key, int keylen, int keyidx)
f0706e82	150	{
c9cf0122	151	u8 *iv;
f0706e82	152	size_t len;
c9cf0122	153	u8 rc4key[3 + WLAN_KEY_LEN_WEP104];
f0706e82	154
c9cf0122 JB	155	iv = ieee80211_wep_add_iv(local, skb, keylen, keyidx);
c9cf0122 JB	156	if (!iv)
f0706e82	157	return -1;
f0706e82 JB	158
	159	len = skb->len - (iv + WEP_IV_LEN - skb->data);
	160
	161	/* Prepend 24-bit IV to RC4 key */
	162	memcpy(rc4key, iv, 3);
	163
	164	/* Copy rest of the WEP key (the secret part) */
c9cf0122	165	memcpy(rc4key + 3, key, keylen);
f0706e82 JB	166
	167	/* Add room for ICV */
	168	skb_put(skb, WEP_ICV_LEN);
	169
c9cf0122	170	ieee80211_wep_encrypt_data(local->wep_tx_tfm, rc4key, keylen + 3,
f0706e82 JB	171	iv + WEP_IV_LEN, len);
f0706e82 JB	172
f0706e82 JB	173	return 0;
	174	}
	175
	176
	177	/* Perform WEP decryption using given key. data buffer includes encrypted
	178	* payload, including 4-byte ICV, but _not_ IV. data_len must not include ICV.
	179	* Return 0 on success and -1 on ICV mismatch. */
	180	int ieee80211_wep_decrypt_data(struct crypto_blkcipher tfm, u8 rc4key,
	181	size_t klen, u8 *data, size_t data_len)
	182	{
	183	struct blkcipher_desc desc = { .tfm = tfm };
	184	struct scatterlist sg;
	185	__le32 crc;
	186
	187	crypto_blkcipher_setkey(tfm, rc4key, klen);
fa05f128	188	sg_init_one(&sg, data, data_len + WEP_ICV_LEN);
f0706e82 JB	189	crypto_blkcipher_decrypt(&desc, &sg, &sg, sg.length);
	190
	191	crc = cpu_to_le32(~crc32_le(~0, data, data_len));
	192	if (memcmp(&crc, data + data_len, WEP_ICV_LEN) != 0)
	193	/* ICV mismatch */
	194	return -1;
	195
	196	return 0;
	197	}
	198
	199
	200	/* Perform WEP decryption on given skb. Buffer includes whole WEP part of
	201	* the frame: IV (4 bytes), encrypted payload (including SNAP header),
	202	* ICV (4 bytes). skb->len includes both IV and ICV.
	203	*
	204	* Returns 0 if frame was decrypted successfully and ICV was correct and -1 on
	205	* failure. If frame is OK, IV and ICV will be removed, i.e., decrypted payload
	206	* is moved to the beginning of the skb and skb length will be reduced.
	207	*/
c9cf0122 JB	208	static int ieee80211_wep_decrypt(struct ieee80211_local *local,
	209	struct sk_buff *skb,
	210	struct ieee80211_key *key)
f0706e82 JB	211	{
	212	u32 klen;
	213	u8 *rc4key;
	214	u8 keyidx;
70217d7f HH	215	struct ieee80211_hdr hdr = (struct ieee80211_hdr )skb->data;
70217d7f HH	216	unsigned int hdrlen;
f0706e82 JB	217	size_t len;
	218	int ret = 0;
	219
70217d7f	220	if (!ieee80211_has_protected(hdr->frame_control))
f0706e82 JB	221	return -1;
f0706e82 JB	222
70217d7f	223	hdrlen = ieee80211_hdrlen(hdr->frame_control);
d2984872	224	if (skb->len < hdrlen + WEP_IV_LEN + WEP_ICV_LEN)
f0706e82 JB	225	return -1;
f0706e82 JB	226
d2984872	227	len = skb->len - hdrlen - WEP_IV_LEN - WEP_ICV_LEN;
f0706e82 JB	228
	229	keyidx = skb->data[hdrlen + 3] >> 6;
	230
8f20fc24	231	if (!key \|\| keyidx != key->conf.keyidx \|\| key->conf.alg != ALG_WEP)
f0706e82 JB	232	return -1;
f0706e82 JB	233
8f20fc24	234	klen = 3 + key->conf.keylen;
f0706e82 JB	235
	236	rc4key = kmalloc(klen, GFP_ATOMIC);
	237	if (!rc4key)
	238	return -1;
	239
	240	/* Prepend 24-bit IV to RC4 key */
	241	memcpy(rc4key, skb->data + hdrlen, 3);
	242
	243	/* Copy rest of the WEP key (the secret part) */
8f20fc24	244	memcpy(rc4key + 3, key->conf.key, key->conf.keylen);
f0706e82 JB	245
	246	if (ieee80211_wep_decrypt_data(local->wep_rx_tfm, rc4key, klen,
	247	skb->data + hdrlen + WEP_IV_LEN,
f4ea83dd	248	len))
f0706e82	249	ret = -1;
f0706e82 JB	250
	251	kfree(rc4key);
	252
	253	/* Trim ICV */
	254	skb_trim(skb, skb->len - WEP_ICV_LEN);
	255
	256	/* Remove IV */
	257	memmove(skb->data + WEP_IV_LEN, skb->data, hdrlen);
	258	skb_pull(skb, WEP_IV_LEN);
	259
	260	return ret;
	261	}
	262
	263
c6a1fa12	264	bool ieee80211_wep_is_weak_iv(struct sk_buff skb, struct ieee80211_key key)
f0706e82	265	{
70217d7f HH	266	struct ieee80211_hdr hdr = (struct ieee80211_hdr )skb->data;
70217d7f HH	267	unsigned int hdrlen;
f0706e82 JB	268	u8 *ivpos;
	269	u32 iv;
	270
70217d7f	271	if (!ieee80211_has_protected(hdr->frame_control))
c6a1fa12	272	return false;
f0706e82	273
70217d7f	274	hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82 JB	275	ivpos = skb->data + hdrlen;
	276	iv = (ivpos[0] << 16) \| (ivpos[1] << 8) \| ivpos[2];
	277
c6a1fa12	278	return ieee80211_wep_weak_iv(iv, key->conf.keylen);
f0706e82	279	}
4f0d18e2	280
9ae54c84	281	ieee80211_rx_result
5cf121c3	282	ieee80211_crypto_wep_decrypt(struct ieee80211_rx_data *rx)
4f0d18e2	283	{
eb9fb5b8 JB	284	struct sk_buff *skb = rx->skb;
	285	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
	286	struct ieee80211_hdr hdr = (struct ieee80211_hdr )skb->data;
358c8d9d HH	287
	288	if (!ieee80211_is_data(hdr->frame_control) &&
	289	!ieee80211_is_auth(hdr->frame_control))
9ae54c84	290	return RX_CONTINUE;
4f0d18e2	291
eb9fb5b8	292	if (!(status->flag & RX_FLAG_DECRYPTED)) {
f4ea83dd	293	if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key))
e4c26add	294	return RX_DROP_UNUSABLE;
eb9fb5b8	295	} else if (!(status->flag & RX_FLAG_IV_STRIPPED)) {
4f0d18e2 JB	296	ieee80211_wep_remove_iv(rx->local, rx->skb, rx->key);
4f0d18e2 JB	297	/* remove ICV */
d2984872	298	skb_trim(rx->skb, rx->skb->len - WEP_ICV_LEN);
4f0d18e2 JB	299	}
4f0d18e2 JB	300
9ae54c84	301	return RX_CONTINUE;
4f0d18e2	302	}
6a22a59d	303
5cf121c3	304	static int wep_encrypt_skb(struct ieee80211_tx_data tx, struct sk_buff skb)
6a22a59d	305	{
e039fa4a JB	306	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
e039fa4a JB	307
6a22a59d	308	if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) {
c9cf0122 JB	309	if (ieee80211_wep_encrypt(tx->local, skb, tx->key->conf.key,
	310	tx->key->conf.keylen,
	311	tx->key->conf.keyidx))
6a22a59d JB	312	return -1;
6a22a59d JB	313	} else {
2b212141	314	info->control.hw_key = &tx->key->conf;
6a22a59d	315	if (tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) {
c9cf0122 JB	316	if (!ieee80211_wep_add_iv(tx->local, skb,
	317	tx->key->conf.keylen,
	318	tx->key->conf.keyidx))
6a22a59d JB	319	return -1;
	320	}
	321	}
	322	return 0;
	323	}
	324
9ae54c84	325	ieee80211_tx_result
5cf121c3	326	ieee80211_crypto_wep_encrypt(struct ieee80211_tx_data *tx)
6a22a59d	327	{
2de8e0d9	328	struct sk_buff *skb;
c6a1fa12	329
5cf121c3	330	ieee80211_tx_set_protected(tx);
6a22a59d	331
2de8e0d9 JB	332	skb = tx->skb;
	333	do {
	334	if (wep_encrypt_skb(tx, skb) < 0) {
	335	I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
	336	return TX_DROP;
6a22a59d	337	}
2de8e0d9	338	} while ((skb = skb->next));
6a22a59d	339
9ae54c84	340	return TX_CONTINUE;
6a22a59d	341	}