[mirror_ubuntu-bionic-kernel.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 <linux/slab.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_cipher("arc4", 0, CRYPTO_ALG_ASYNC);
	if (IS_ERR(local->wep_tx_tfm)) {
		local->wep_rx_tfm = ERR_PTR(-EINVAL);
		return PTR_ERR(local->wep_tx_tfm);
	}

	local->wep_rx_tfm = crypto_alloc_cipher("arc4", 0, CRYPTO_ALG_ASYNC);
	if (IS_ERR(local->wep_rx_tfm)) {
		crypto_free_cipher(local->wep_tx_tfm);
		local->wep_tx_tfm = ERR_PTR(-EINVAL);
		return PTR_ERR(local->wep_rx_tfm);
	}

	return 0;
}

void ieee80211_wep_free(struct ieee80211_local *local)
{
	if (!IS_ERR(local->wep_tx_tfm))
		crypto_free_cipher(local->wep_tx_tfm);
	if (!IS_ERR(local->wep_rx_tfm))
		crypto_free_cipher(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)) */
int ieee80211_wep_encrypt_data(struct crypto_cipher *tfm, u8 *rc4key,
			       size_t klen, u8 *data, size_t data_len)
{
	__le32 icv;
	int i;

	if (IS_ERR(tfm))
		return -1;

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

	crypto_cipher_setkey(tfm, rc4key, klen);
	for (i = 0; i < data_len + WEP_ICV_LEN; i++)
		crypto_cipher_encrypt_one(tfm, data + i, data + i);

	return 0;
}


/* 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);

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


/* 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_cipher *tfm, u8 *rc4key,
			       size_t klen, u8 *data, size_t data_len)
{
	__le32 crc;
	int i;

	if (IS_ERR(tfm))
		return -1;

	crypto_cipher_setkey(tfm, rc4key, klen);
	for (i = 0; i < data_len + WEP_ICV_LEN; i++)
		crypto_cipher_decrypt_one(tfm, data + i, data + i);

	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[3 + WLAN_KEY_LEN_WEP104];
	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)
		return -1;

	klen = 3 + key->conf.keylen;

	/* 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;

	/* 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;
}


static 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;

	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;
	__le16 fc = hdr->frame_control;

	if (!ieee80211_is_data(fc) && !ieee80211_is_auth(fc))
		return RX_CONTINUE;

	if (!(status->flag & RX_FLAG_DECRYPTED)) {
		if (skb_linearize(rx->skb))
			return RX_DROP_UNUSABLE;
		if (rx->sta && ieee80211_wep_is_weak_iv(rx->skb, rx->key))
			rx->sta->wep_weak_iv_count++;
		if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key))
			return RX_DROP_UNUSABLE;
	} else if (!(status->flag & RX_FLAG_IV_STRIPPED)) {
		if (!pskb_may_pull(rx->skb, ieee80211_hdrlen(fc) + WEP_IV_LEN))
			return RX_DROP_UNUSABLE;
		if (rx->sta && ieee80211_wep_is_weak_iv(rx->skb, rx->key))
			rx->sta->wep_weak_iv_count++;
		ieee80211_wep_remove_iv(rx->local, rx->skb, rx->key);
		/* remove ICV */
		if (pskb_trim(rx->skb, rx->skb->len - WEP_ICV_LEN))
			return RX_DROP_UNUSABLE;
	}

	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 (!info->control.hw_key) {
		if (ieee80211_wep_encrypt(tx->local, skb, tx->key->conf.key,
					  tx->key->conf.keylen,
					  tx->key->conf.keyidx))
			return -1;
	} else if (info->control.hw_key->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_queue_walk(&tx->skbs, skb) {
		if (wep_encrypt_skb(tx, skb) < 0) {
			I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
			return TX_DROP;
		}
	}

	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>
5a0e3ad6	20	#include <linux/slab.h>
860c6e6a	21	#include <asm/unaligned.h>
f0706e82 JB	22
	23	#include <net/mac80211.h>
	24	#include "ieee80211_i.h"
	25	#include "wep.h"
	26
	27
	28	int ieee80211_wep_init(struct ieee80211_local *local)
	29	{
	30	/* start WEP IV from a random value */
	31	get_random_bytes(&local->wep_iv, WEP_IV_LEN);
	32
5f9f1812	33	local->wep_tx_tfm = crypto_alloc_cipher("arc4", 0, CRYPTO_ALG_ASYNC);
088c8726 JL	34	if (IS_ERR(local->wep_tx_tfm)) {
088c8726 JL	35	local->wep_rx_tfm = ERR_PTR(-EINVAL);
023a04be	36	return PTR_ERR(local->wep_tx_tfm);
088c8726	37	}
f0706e82	38
5f9f1812	39	local->wep_rx_tfm = crypto_alloc_cipher("arc4", 0, CRYPTO_ALG_ASYNC);
f0706e82	40	if (IS_ERR(local->wep_rx_tfm)) {
5f9f1812	41	crypto_free_cipher(local->wep_tx_tfm);
088c8726	42	local->wep_tx_tfm = ERR_PTR(-EINVAL);
023a04be	43	return PTR_ERR(local->wep_rx_tfm);
f0706e82 JB	44	}
	45
	46	return 0;
	47	}
	48
	49	void ieee80211_wep_free(struct ieee80211_local *local)
	50	{
3473187d	51	if (!IS_ERR(local->wep_tx_tfm))
5f9f1812	52	crypto_free_cipher(local->wep_tx_tfm);
3473187d	53	if (!IS_ERR(local->wep_rx_tfm))
5f9f1812	54	crypto_free_cipher(local->wep_rx_tfm);
f0706e82 JB	55	}
f0706e82 JB	56
c6a1fa12	57	static inline bool ieee80211_wep_weak_iv(u32 iv, int keylen)
f0706e82	58	{
c6a1fa12 JB	59	/*
c6a1fa12 JB	60	* Fluhrer, Mantin, and Shamir have reported weaknesses in the
f0706e82	61	* key scheduling algorithm of RC4. At least IVs (KeyByte + 3,
c6a1fa12 JB	62	* 0xff, N) can be used to speedup attacks, so avoid using them.
c6a1fa12 JB	63	*/
f0706e82 JB	64	if ((iv & 0xff00) == 0xff00) {
	65	u8 B = (iv >> 16) & 0xff;
	66	if (B >= 3 && B < 3 + keylen)
c6a1fa12	67	return true;
f0706e82	68	}
c6a1fa12	69	return false;
f0706e82 JB	70	}
	71
	72
4f0d18e2	73	static void ieee80211_wep_get_iv(struct ieee80211_local *local,
c9cf0122	74	int keylen, int keyidx, u8 *iv)
f0706e82 JB	75	{
f0706e82 JB	76	local->wep_iv++;
c9cf0122	77	if (ieee80211_wep_weak_iv(local->wep_iv, keylen))
f0706e82 JB	78	local->wep_iv += 0x0100;
	79
	80	if (!iv)
	81	return;
	82
	83	*iv++ = (local->wep_iv >> 16) & 0xff;
	84	*iv++ = (local->wep_iv >> 8) & 0xff;
	85	*iv++ = local->wep_iv & 0xff;
c9cf0122	86	*iv++ = keyidx << 6;
f0706e82 JB	87	}
	88
	89
6a22a59d JB	90	static u8 ieee80211_wep_add_iv(struct ieee80211_local local,
6a22a59d JB	91	struct sk_buff *skb,
c9cf0122	92	int keylen, int keyidx)
f0706e82	93	{
70217d7f HH	94	struct ieee80211_hdr hdr = (struct ieee80211_hdr )skb->data;
70217d7f HH	95	unsigned int hdrlen;
f0706e82 JB	96	u8 *newhdr;
f0706e82 JB	97
70217d7f	98	hdr->frame_control \|= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
f0706e82	99
23c0752a JB	100	if (WARN_ON(skb_tailroom(skb) < WEP_ICV_LEN \|\|
	101	skb_headroom(skb) < WEP_IV_LEN))
	102	return NULL;
f0706e82	103
70217d7f	104	hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82 JB	105	newhdr = skb_push(skb, WEP_IV_LEN);
f0706e82 JB	106	memmove(newhdr, newhdr + WEP_IV_LEN, hdrlen);
c9cf0122	107	ieee80211_wep_get_iv(local, keylen, keyidx, newhdr + hdrlen);
f0706e82 JB	108	return newhdr + hdrlen;
	109	}
	110
	111
4f0d18e2 JB	112	static void ieee80211_wep_remove_iv(struct ieee80211_local *local,
	113	struct sk_buff *skb,
	114	struct ieee80211_key *key)
f0706e82	115	{
70217d7f HH	116	struct ieee80211_hdr hdr = (struct ieee80211_hdr )skb->data;
70217d7f HH	117	unsigned int hdrlen;
f0706e82	118
70217d7f	119	hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82 JB	120	memmove(skb->data + WEP_IV_LEN, skb->data, hdrlen);
	121	skb_pull(skb, WEP_IV_LEN);
	122	}
	123
	124
	125	/* Perform WEP encryption using given key. data buffer must have tailroom
	126	* for 4-byte ICV. data_len must not include this ICV. Note: this function
	127	* does _not_ add IV. data = RC4(data \| CRC32(data)) */
5f9f1812	128	int ieee80211_wep_encrypt_data(struct crypto_cipher tfm, u8 rc4key,
3473187d	129	size_t klen, u8 *data, size_t data_len)
f0706e82	130	{
860c6e6a	131	__le32 icv;
5f9f1812	132	int i;
f0706e82	133
3473187d JL	134	if (IS_ERR(tfm))
	135	return -1;
	136
860c6e6a IK	137	icv = cpu_to_le32(~crc32_le(~0, data, data_len));
860c6e6a IK	138	put_unaligned(icv, (__le32 *)(data + data_len));
f0706e82	139
5f9f1812 FF	140	crypto_cipher_setkey(tfm, rc4key, klen);
	141	for (i = 0; i < data_len + WEP_ICV_LEN; i++)
	142	crypto_cipher_encrypt_one(tfm, data + i, data + i);
3473187d JL	143
3473187d JL	144	return 0;
f0706e82 JB	145	}
	146
	147
	148	/* Perform WEP encryption on given skb. 4 bytes of extra space (IV) in the
	149	* beginning of the buffer 4 bytes of extra space (ICV) in the end of the
	150	* buffer will be added. Both IV and ICV will be transmitted, so the
	151	* payload length increases with 8 bytes.
	152	*
	153	* WEP frame payload: IV + TX key idx, RC4(data), ICV = RC4(CRC32(data))
	154	*/
fffd0934 JB	155	int ieee80211_wep_encrypt(struct ieee80211_local *local,
	156	struct sk_buff *skb,
	157	const u8 *key, int keylen, int keyidx)
f0706e82	158	{
c9cf0122	159	u8 *iv;
f0706e82	160	size_t len;
c9cf0122	161	u8 rc4key[3 + WLAN_KEY_LEN_WEP104];
f0706e82	162
c9cf0122 JB	163	iv = ieee80211_wep_add_iv(local, skb, keylen, keyidx);
c9cf0122 JB	164	if (!iv)
f0706e82	165	return -1;
f0706e82 JB	166
	167	len = skb->len - (iv + WEP_IV_LEN - skb->data);
	168
	169	/* Prepend 24-bit IV to RC4 key */
	170	memcpy(rc4key, iv, 3);
	171
	172	/* Copy rest of the WEP key (the secret part) */
c9cf0122	173	memcpy(rc4key + 3, key, keylen);
f0706e82 JB	174
	175	/* Add room for ICV */
	176	skb_put(skb, WEP_ICV_LEN);
	177
3473187d JL	178	return ieee80211_wep_encrypt_data(local->wep_tx_tfm, rc4key, keylen + 3,
3473187d JL	179	iv + WEP_IV_LEN, len);
f0706e82 JB	180	}
	181
	182
	183	/* Perform WEP decryption using given key. data buffer includes encrypted
	184	* payload, including 4-byte ICV, but _not_ IV. data_len must not include ICV.
	185	* Return 0 on success and -1 on ICV mismatch. */
5f9f1812	186	int ieee80211_wep_decrypt_data(struct crypto_cipher tfm, u8 rc4key,
f0706e82 JB	187	size_t klen, u8 *data, size_t data_len)
f0706e82 JB	188	{
f0706e82	189	__le32 crc;
5f9f1812	190	int i;
f0706e82	191
3473187d JL	192	if (IS_ERR(tfm))
	193	return -1;
	194
5f9f1812 FF	195	crypto_cipher_setkey(tfm, rc4key, klen);
	196	for (i = 0; i < data_len + WEP_ICV_LEN; i++)
	197	crypto_cipher_decrypt_one(tfm, data + i, data + i);
f0706e82 JB	198
	199	crc = cpu_to_le32(~crc32_le(~0, data, data_len));
	200	if (memcmp(&crc, data + data_len, WEP_ICV_LEN) != 0)
	201	/* ICV mismatch */
	202	return -1;
	203
	204	return 0;
	205	}
	206
	207
	208	/* Perform WEP decryption on given skb. Buffer includes whole WEP part of
	209	* the frame: IV (4 bytes), encrypted payload (including SNAP header),
	210	* ICV (4 bytes). skb->len includes both IV and ICV.
	211	*
	212	* Returns 0 if frame was decrypted successfully and ICV was correct and -1 on
	213	* failure. If frame is OK, IV and ICV will be removed, i.e., decrypted payload
	214	* is moved to the beginning of the skb and skb length will be reduced.
	215	*/
c9cf0122 JB	216	static int ieee80211_wep_decrypt(struct ieee80211_local *local,
	217	struct sk_buff *skb,
	218	struct ieee80211_key *key)
f0706e82 JB	219	{
f0706e82 JB	220	u32 klen;
730bd83b	221	u8 rc4key[3 + WLAN_KEY_LEN_WEP104];
f0706e82	222	u8 keyidx;
70217d7f HH	223	struct ieee80211_hdr hdr = (struct ieee80211_hdr )skb->data;
70217d7f HH	224	unsigned int hdrlen;
f0706e82 JB	225	size_t len;
	226	int ret = 0;
	227
70217d7f	228	if (!ieee80211_has_protected(hdr->frame_control))
f0706e82 JB	229	return -1;
f0706e82 JB	230
70217d7f	231	hdrlen = ieee80211_hdrlen(hdr->frame_control);
d2984872	232	if (skb->len < hdrlen + WEP_IV_LEN + WEP_ICV_LEN)
f0706e82 JB	233	return -1;
f0706e82 JB	234
d2984872	235	len = skb->len - hdrlen - WEP_IV_LEN - WEP_ICV_LEN;
f0706e82 JB	236
	237	keyidx = skb->data[hdrlen + 3] >> 6;
	238
97359d12	239	if (!key \|\| keyidx != key->conf.keyidx)
f0706e82 JB	240	return -1;
f0706e82 JB	241
8f20fc24	242	klen = 3 + key->conf.keylen;
f0706e82	243
f0706e82 JB	244	/* Prepend 24-bit IV to RC4 key */
	245	memcpy(rc4key, skb->data + hdrlen, 3);
	246
	247	/* Copy rest of the WEP key (the secret part) */
8f20fc24	248	memcpy(rc4key + 3, key->conf.key, key->conf.keylen);
f0706e82 JB	249
	250	if (ieee80211_wep_decrypt_data(local->wep_rx_tfm, rc4key, klen,
	251	skb->data + hdrlen + WEP_IV_LEN,
f4ea83dd	252	len))
f0706e82	253	ret = -1;
f0706e82	254
f0706e82 JB	255	/* Trim ICV */
	256	skb_trim(skb, skb->len - WEP_ICV_LEN);
	257
	258	/* Remove IV */
	259	memmove(skb->data + WEP_IV_LEN, skb->data, hdrlen);
	260	skb_pull(skb, WEP_IV_LEN);
	261
	262	return ret;
	263	}
	264
	265
617bbde8 JB	266	static bool ieee80211_wep_is_weak_iv(struct sk_buff *skb,
617bbde8 JB	267	struct ieee80211_key *key)
f0706e82	268	{
70217d7f HH	269	struct ieee80211_hdr hdr = (struct ieee80211_hdr )skb->data;
70217d7f HH	270	unsigned int hdrlen;
f0706e82 JB	271	u8 *ivpos;
	272	u32 iv;
	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;
a8286911	287	__le16 fc = hdr->frame_control;
358c8d9d	288
a8286911	289	if (!ieee80211_is_data(fc) && !ieee80211_is_auth(fc))
9ae54c84	290	return RX_CONTINUE;
4f0d18e2	291
eb9fb5b8	292	if (!(status->flag & RX_FLAG_DECRYPTED)) {
a8286911 JB	293	if (skb_linearize(rx->skb))
a8286911 JB	294	return RX_DROP_UNUSABLE;
617bbde8 JB	295	if (rx->sta && ieee80211_wep_is_weak_iv(rx->skb, rx->key))
617bbde8 JB	296	rx->sta->wep_weak_iv_count++;
f4ea83dd	297	if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key))
e4c26add	298	return RX_DROP_UNUSABLE;
eb9fb5b8	299	} else if (!(status->flag & RX_FLAG_IV_STRIPPED)) {
a8286911 JB	300	if (!pskb_may_pull(rx->skb, ieee80211_hdrlen(fc) + WEP_IV_LEN))
a8286911 JB	301	return RX_DROP_UNUSABLE;
617bbde8 JB	302	if (rx->sta && ieee80211_wep_is_weak_iv(rx->skb, rx->key))
617bbde8 JB	303	rx->sta->wep_weak_iv_count++;
4f0d18e2 JB	304	ieee80211_wep_remove_iv(rx->local, rx->skb, rx->key);
4f0d18e2 JB	305	/* remove ICV */
a8286911 JB	306	if (pskb_trim(rx->skb, rx->skb->len - WEP_ICV_LEN))
a8286911 JB	307	return RX_DROP_UNUSABLE;
4f0d18e2 JB	308	}
4f0d18e2 JB	309
9ae54c84	310	return RX_CONTINUE;
4f0d18e2	311	}
6a22a59d	312
5cf121c3	313	static int wep_encrypt_skb(struct ieee80211_tx_data tx, struct sk_buff skb)
6a22a59d	314	{
e039fa4a JB	315	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
e039fa4a JB	316
813d7669	317	if (!info->control.hw_key) {
c9cf0122 JB	318	if (ieee80211_wep_encrypt(tx->local, skb, tx->key->conf.key,
	319	tx->key->conf.keylen,
	320	tx->key->conf.keyidx))
6a22a59d	321	return -1;
e4fca007 JL	322	} else if (info->control.hw_key->flags &
e4fca007 JL	323	IEEE80211_KEY_FLAG_GENERATE_IV) {
813d7669 JB	324	if (!ieee80211_wep_add_iv(tx->local, skb,
	325	tx->key->conf.keylen,
	326	tx->key->conf.keyidx))
	327	return -1;
	328	}
	329
6a22a59d JB	330	return 0;
	331	}
	332
9ae54c84	333	ieee80211_tx_result
5cf121c3	334	ieee80211_crypto_wep_encrypt(struct ieee80211_tx_data *tx)
6a22a59d	335	{
2de8e0d9	336	struct sk_buff *skb;
c6a1fa12	337
5cf121c3	338	ieee80211_tx_set_protected(tx);
6a22a59d	339
252b86c4	340	skb_queue_walk(&tx->skbs, skb) {
2de8e0d9 JB	341	if (wep_encrypt_skb(tx, skb) < 0) {
	342	I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
	343	return TX_DROP;
6a22a59d	344	}
252b86c4	345	}
6a22a59d	346
9ae54c84	347	return TX_CONTINUE;
6a22a59d	348	}