[mirror_ubuntu-zesty-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 <asm/scatterlist.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 -ENOMEM;

	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 -ENOMEM;
	}

	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 int 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 1;
	}
	return 0;
}


static void ieee80211_wep_get_iv(struct ieee80211_local *local,
				 struct ieee80211_key *key, u8 *iv)
{
	local->wep_iv++;
	if (ieee80211_wep_weak_iv(local->wep_iv, key->conf.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++ = key->conf.keyidx << 6;
}


static u8 *ieee80211_wep_add_iv(struct ieee80211_local *local,
				struct sk_buff *skb,
				struct ieee80211_key *key)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	u16 fc;
	int hdrlen;
	u8 *newhdr;

	fc = le16_to_cpu(hdr->frame_control);
	fc |= IEEE80211_FCTL_PROTECTED;
	hdr->frame_control = cpu_to_le16(fc);

	if ((skb_headroom(skb) < WEP_IV_LEN ||
	     skb_tailroom(skb) < WEP_ICV_LEN)) {
		I802_DEBUG_INC(local->tx_expand_skb_head);
		if (unlikely(pskb_expand_head(skb, WEP_IV_LEN, WEP_ICV_LEN,
					      GFP_ATOMIC)))
			return NULL;
	}

	hdrlen = ieee80211_get_hdrlen(fc);
	newhdr = skb_push(skb, WEP_IV_LEN);
	memmove(newhdr, newhdr + WEP_IV_LEN, hdrlen);
	ieee80211_wep_get_iv(local, key, 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;
	u16 fc;
	int hdrlen;

	fc = le16_to_cpu(hdr->frame_control);
	hdrlen = ieee80211_get_hdrlen(fc);
	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 = (__le32 *)(data + data_len);
	*icv = cpu_to_le32(~crc32_le(~0, data, data_len));

	crypto_blkcipher_setkey(tfm, rc4key, klen);
	sg.page = virt_to_page(data);
	sg.offset = offset_in_page(data);
	sg.length = 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,
			  struct ieee80211_key *key)
{
	u32 klen;
	u8 *rc4key, *iv;
	size_t len;

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

	klen = 3 + key->conf.keylen;
	rc4key = kmalloc(klen, GFP_ATOMIC);
	if (!rc4key)
		return -1;

	iv = ieee80211_wep_add_iv(local, skb, key);
	if (!iv) {
		kfree(rc4key);
		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->conf.key, key->conf.keylen);

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

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

	kfree(rc4key);

	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.page = virt_to_page(data);
	sg.offset = offset_in_page(data);
	sg.length = 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.
 */
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;
	u16 fc;
	int hdrlen;
	size_t len;
	int ret = 0;

	fc = le16_to_cpu(hdr->frame_control);
	if (!(fc & IEEE80211_FCTL_PROTECTED))
		return -1;

	hdrlen = ieee80211_get_hdrlen(fc);

	if (skb->len < 8 + hdrlen)
		return -1;

	len = skb->len - hdrlen - 8;

	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)) {
		printk(KERN_DEBUG "WEP decrypt failed (ICV)\n");
		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;
}


u8 * ieee80211_wep_is_weak_iv(struct sk_buff *skb, struct ieee80211_key *key)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	u16 fc;
	int hdrlen;
	u8 *ivpos;
	u32 iv;

	fc = le16_to_cpu(hdr->frame_control);
	if (!(fc & IEEE80211_FCTL_PROTECTED))
		return NULL;

	hdrlen = ieee80211_get_hdrlen(fc);
	ivpos = skb->data + hdrlen;
	iv = (ivpos[0] << 16) | (ivpos[1] << 8) | ivpos[2];

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

	return NULL;
}

ieee80211_txrx_result
ieee80211_crypto_wep_decrypt(struct ieee80211_txrx_data *rx)
{
	if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
	    ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
	     (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH))
		return TXRX_CONTINUE;

	if (!(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) {
		if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key)) {
			if (net_ratelimit())
				printk(KERN_DEBUG "%s: RX WEP frame, decrypt "
				       "failed\n", rx->dev->name);
			return TXRX_DROP;
		}
	} else if (!(rx->u.rx.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 - 4);
	}

	return TXRX_CONTINUE;
}

static int wep_encrypt_skb(struct ieee80211_txrx_data *tx, struct sk_buff *skb)
{
	if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) {
		if (ieee80211_wep_encrypt(tx->local, skb, tx->key))
			return -1;
	} else {
		tx->u.tx.control->key_idx = tx->key->conf.hw_key_idx;
		if (tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) {
			if (!ieee80211_wep_add_iv(tx->local, skb, tx->key))
				return -1;
		}
	}
	return 0;
}

ieee80211_txrx_result
ieee80211_crypto_wep_encrypt(struct ieee80211_txrx_data *tx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
	u16 fc;

	fc = le16_to_cpu(hdr->frame_control);

	if (((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
	     ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
	      (fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)))
		return TXRX_CONTINUE;

	tx->u.tx.control->iv_len = WEP_IV_LEN;
	tx->u.tx.control->icv_len = WEP_ICV_LEN;
	ieee80211_tx_set_iswep(tx);

	if (wep_encrypt_skb(tx, tx->skb) < 0) {
		I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
		return TXRX_DROP;
	}

	if (tx->u.tx.extra_frag) {
		int i;
		for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
			if (wep_encrypt_skb(tx, tx->u.tx.extra_frag[i]) < 0) {
				I802_DEBUG_INC(tx->local->
					       tx_handlers_drop_wep);
				return TXRX_DROP;
			}
		}
	}

	return TXRX_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>
	19	#include <asm/scatterlist.h>
	20
	21	#include <net/mac80211.h>
	22	#include "ieee80211_i.h"
	23	#include "wep.h"
	24
	25
	26	int ieee80211_wep_init(struct ieee80211_local *local)
	27	{
	28	/* start WEP IV from a random value */
	29	get_random_bytes(&local->wep_iv, WEP_IV_LEN);
	30
	31	local->wep_tx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0,
	32	CRYPTO_ALG_ASYNC);
	33	if (IS_ERR(local->wep_tx_tfm))
	34	return -ENOMEM;
	35
	36	local->wep_rx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0,
	37	CRYPTO_ALG_ASYNC);
	38	if (IS_ERR(local->wep_rx_tfm)) {
	39	crypto_free_blkcipher(local->wep_tx_tfm);
	40	return -ENOMEM;
	41	}
	42
	43	return 0;
	44	}
	45
	46	void ieee80211_wep_free(struct ieee80211_local *local)
	47	{
	48	crypto_free_blkcipher(local->wep_tx_tfm);
	49	crypto_free_blkcipher(local->wep_rx_tfm);
	50	}
	51
	52	static inline int ieee80211_wep_weak_iv(u32 iv, int keylen)
	53	{
	54	/* Fluhrer, Mantin, and Shamir have reported weaknesses in the
	55	* key scheduling algorithm of RC4. At least IVs (KeyByte + 3,
	56	* 0xff, N) can be used to speedup attacks, so avoid using them. */
	57	if ((iv & 0xff00) == 0xff00) {
	58	u8 B = (iv >> 16) & 0xff;
	59	if (B >= 3 && B < 3 + keylen)
	60	return 1;
	61	}
	62	return 0;
	63	}
	64
65
4f0d18e2 JB	66	static void ieee80211_wep_get_iv(struct ieee80211_local *local,
4f0d18e2 JB	67	struct ieee80211_key key, u8 iv)
f0706e82 JB	68	{
f0706e82 JB	69	local->wep_iv++;
8f20fc24	70	if (ieee80211_wep_weak_iv(local->wep_iv, key->conf.keylen))
f0706e82 JB	71	local->wep_iv += 0x0100;
	72
	73	if (!iv)
	74	return;
	75
	76	*iv++ = (local->wep_iv >> 16) & 0xff;
	77	*iv++ = (local->wep_iv >> 8) & 0xff;
	78	*iv++ = local->wep_iv & 0xff;
8f20fc24	79	*iv++ = key->conf.keyidx << 6;
f0706e82 JB	80	}
	81
	82
6a22a59d JB	83	static u8 ieee80211_wep_add_iv(struct ieee80211_local local,
	84	struct sk_buff *skb,
	85	struct ieee80211_key *key)
f0706e82 JB	86	{
	87	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
	88	u16 fc;
	89	int hdrlen;
	90	u8 *newhdr;
	91
	92	fc = le16_to_cpu(hdr->frame_control);
	93	fc \|= IEEE80211_FCTL_PROTECTED;
	94	hdr->frame_control = cpu_to_le16(fc);
	95
	96	if ((skb_headroom(skb) < WEP_IV_LEN \|\|
	97	skb_tailroom(skb) < WEP_ICV_LEN)) {
	98	I802_DEBUG_INC(local->tx_expand_skb_head);
	99	if (unlikely(pskb_expand_head(skb, WEP_IV_LEN, WEP_ICV_LEN,
	100	GFP_ATOMIC)))
	101	return NULL;
	102	}
	103
	104	hdrlen = ieee80211_get_hdrlen(fc);
	105	newhdr = skb_push(skb, WEP_IV_LEN);
	106	memmove(newhdr, newhdr + WEP_IV_LEN, hdrlen);
	107	ieee80211_wep_get_iv(local, key, newhdr + hdrlen);
	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 JB	115	{
	116	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
	117	u16 fc;
	118	int hdrlen;
	119
	120	fc = le16_to_cpu(hdr->frame_control);
	121	hdrlen = ieee80211_get_hdrlen(fc);
	122	memmove(skb->data + WEP_IV_LEN, skb->data, hdrlen);
	123	skb_pull(skb, WEP_IV_LEN);
	124	}
	125
	126
	127	/* Perform WEP encryption using given key. data buffer must have tailroom
	128	* for 4-byte ICV. data_len must not include this ICV. Note: this function
	129	* does _not_ add IV. data = RC4(data \| CRC32(data)) */
	130	void ieee80211_wep_encrypt_data(struct crypto_blkcipher tfm, u8 rc4key,
	131	size_t klen, u8 *data, size_t data_len)
	132	{
	133	struct blkcipher_desc desc = { .tfm = tfm };
	134	struct scatterlist sg;
	135	__le32 *icv;
	136
	137	icv = (__le32 *)(data + data_len);
	138	*icv = cpu_to_le32(~crc32_le(~0, data, data_len));
	139
	140	crypto_blkcipher_setkey(tfm, rc4key, klen);
	141	sg.page = virt_to_page(data);
	142	sg.offset = offset_in_page(data);
	143	sg.length = data_len + WEP_ICV_LEN;
	144	crypto_blkcipher_encrypt(&desc, &sg, &sg, sg.length);
	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	*/
	155	int ieee80211_wep_encrypt(struct ieee80211_local local, struct sk_buff skb,
	156	struct ieee80211_key *key)
	157	{
	158	u32 klen;
	159	u8 rc4key, iv;
	160	size_t len;
	161
8f20fc24	162	if (!key \|\| key->conf.alg != ALG_WEP)
f0706e82 JB	163	return -1;
f0706e82 JB	164
8f20fc24	165	klen = 3 + key->conf.keylen;
f0706e82 JB	166	rc4key = kmalloc(klen, GFP_ATOMIC);
	167	if (!rc4key)
	168	return -1;
	169
	170	iv = ieee80211_wep_add_iv(local, skb, key);
	171	if (!iv) {
	172	kfree(rc4key);
	173	return -1;
	174	}
	175
	176	len = skb->len - (iv + WEP_IV_LEN - skb->data);
	177
	178	/* Prepend 24-bit IV to RC4 key */
	179	memcpy(rc4key, iv, 3);
	180
	181	/* Copy rest of the WEP key (the secret part) */
8f20fc24	182	memcpy(rc4key + 3, key->conf.key, key->conf.keylen);
f0706e82 JB	183
	184	/* Add room for ICV */
	185	skb_put(skb, WEP_ICV_LEN);
	186
	187	ieee80211_wep_encrypt_data(local->wep_tx_tfm, rc4key, klen,
	188	iv + WEP_IV_LEN, len);
	189
	190	kfree(rc4key);
	191
	192	return 0;
	193	}
	194
	195
	196	/* Perform WEP decryption using given key. data buffer includes encrypted
	197	* payload, including 4-byte ICV, but _not_ IV. data_len must not include ICV.
	198	* Return 0 on success and -1 on ICV mismatch. */
	199	int ieee80211_wep_decrypt_data(struct crypto_blkcipher tfm, u8 rc4key,
	200	size_t klen, u8 *data, size_t data_len)
	201	{
	202	struct blkcipher_desc desc = { .tfm = tfm };
	203	struct scatterlist sg;
	204	__le32 crc;
	205
	206	crypto_blkcipher_setkey(tfm, rc4key, klen);
	207	sg.page = virt_to_page(data);
	208	sg.offset = offset_in_page(data);
	209	sg.length = data_len + WEP_ICV_LEN;
	210	crypto_blkcipher_decrypt(&desc, &sg, &sg, sg.length);
	211
	212	crc = cpu_to_le32(~crc32_le(~0, data, data_len));
	213	if (memcmp(&crc, data + data_len, WEP_ICV_LEN) != 0)
	214	/* ICV mismatch */
	215	return -1;
	216
	217	return 0;
	218	}
	219
	220
	221	/* Perform WEP decryption on given skb. Buffer includes whole WEP part of
	222	* the frame: IV (4 bytes), encrypted payload (including SNAP header),
	223	* ICV (4 bytes). skb->len includes both IV and ICV.
	224	*
	225	* Returns 0 if frame was decrypted successfully and ICV was correct and -1 on
	226	* failure. If frame is OK, IV and ICV will be removed, i.e., decrypted payload
	227	* is moved to the beginning of the skb and skb length will be reduced.
	228	*/
	229	int ieee80211_wep_decrypt(struct ieee80211_local local, struct sk_buff skb,
	230	struct ieee80211_key *key)
	231	{
	232	u32 klen;
	233	u8 *rc4key;
	234	u8 keyidx;
	235	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
	236	u16 fc;
	237	int hdrlen;
	238	size_t len;
	239	int ret = 0;
	240
	241	fc = le16_to_cpu(hdr->frame_control);
	242	if (!(fc & IEEE80211_FCTL_PROTECTED))
	243	return -1;
	244
	245	hdrlen = ieee80211_get_hdrlen(fc);
	246
247	if (skb->len < 8 + hdrlen)
248	return -1;
249
250	len = skb->len - hdrlen - 8;
251
252	keyidx = skb->data[hdrlen + 3] >> 6;
253
8f20fc24	254	if (!key \|\| keyidx != key->conf.keyidx \|\| key->conf.alg != ALG_WEP)
f0706e82 JB	255	return -1;
f0706e82 JB	256
8f20fc24	257	klen = 3 + key->conf.keylen;
f0706e82 JB	258
	259	rc4key = kmalloc(klen, GFP_ATOMIC);
	260	if (!rc4key)
	261	return -1;
	262
	263	/* Prepend 24-bit IV to RC4 key */
	264	memcpy(rc4key, skb->data + hdrlen, 3);
	265
	266	/* Copy rest of the WEP key (the secret part) */
8f20fc24	267	memcpy(rc4key + 3, key->conf.key, key->conf.keylen);
f0706e82 JB	268
	269	if (ieee80211_wep_decrypt_data(local->wep_rx_tfm, rc4key, klen,
	270	skb->data + hdrlen + WEP_IV_LEN,
	271	len)) {
	272	printk(KERN_DEBUG "WEP decrypt failed (ICV)\n");
	273	ret = -1;
	274	}
	275
	276	kfree(rc4key);
	277
	278	/* Trim ICV */
	279	skb_trim(skb, skb->len - WEP_ICV_LEN);
	280
	281	/* Remove IV */
	282	memmove(skb->data + WEP_IV_LEN, skb->data, hdrlen);
	283	skb_pull(skb, WEP_IV_LEN);
	284
	285	return ret;
	286	}
	287
	288
f0706e82 JB	289	u8 * ieee80211_wep_is_weak_iv(struct sk_buff skb, struct ieee80211_key key)
	290	{
	291	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
	292	u16 fc;
	293	int hdrlen;
	294	u8 *ivpos;
	295	u32 iv;
	296
	297	fc = le16_to_cpu(hdr->frame_control);
	298	if (!(fc & IEEE80211_FCTL_PROTECTED))
	299	return NULL;
	300
	301	hdrlen = ieee80211_get_hdrlen(fc);
	302	ivpos = skb->data + hdrlen;
	303	iv = (ivpos[0] << 16) \| (ivpos[1] << 8) \| ivpos[2];
	304
8f20fc24	305	if (ieee80211_wep_weak_iv(iv, key->conf.keylen))
f0706e82 JB	306	return ivpos;
	307
	308	return NULL;
	309	}
4f0d18e2 JB	310
	311	ieee80211_txrx_result
	312	ieee80211_crypto_wep_decrypt(struct ieee80211_txrx_data *rx)
	313	{
	314	if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
	315	((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT \|\|
	316	(rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH))
	317	return TXRX_CONTINUE;
	318
	319	if (!(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) {
	320	if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key)) {
	321	if (net_ratelimit())
	322	printk(KERN_DEBUG "%s: RX WEP frame, decrypt "
	323	"failed\n", rx->dev->name);
	324	return TXRX_DROP;
	325	}
	326	} else if (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED)) {
	327	ieee80211_wep_remove_iv(rx->local, rx->skb, rx->key);
	328	/* remove ICV */
	329	skb_trim(rx->skb, rx->skb->len - 4);
	330	}
	331
	332	return TXRX_CONTINUE;
	333	}
6a22a59d JB	334
	335	static int wep_encrypt_skb(struct ieee80211_txrx_data tx, struct sk_buff skb)
	336	{
	337	if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) {
	338	if (ieee80211_wep_encrypt(tx->local, skb, tx->key))
	339	return -1;
	340	} else {
	341	tx->u.tx.control->key_idx = tx->key->conf.hw_key_idx;
	342	if (tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) {
	343	if (!ieee80211_wep_add_iv(tx->local, skb, tx->key))
	344	return -1;
	345	}
	346	}
	347	return 0;
	348	}
	349
	350	ieee80211_txrx_result
	351	ieee80211_crypto_wep_encrypt(struct ieee80211_txrx_data *tx)
	352	{
	353	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) tx->skb->data;
	354	u16 fc;
	355
	356	fc = le16_to_cpu(hdr->frame_control);
	357
	358	if (((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
	359	((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT \|\|
	360	(fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)))
	361	return TXRX_CONTINUE;
	362
	363	tx->u.tx.control->iv_len = WEP_IV_LEN;
	364	tx->u.tx.control->icv_len = WEP_ICV_LEN;
	365	ieee80211_tx_set_iswep(tx);
	366
	367	if (wep_encrypt_skb(tx, tx->skb) < 0) {
	368	I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
	369	return TXRX_DROP;
	370	}
	371
	372	if (tx->u.tx.extra_frag) {
	373	int i;
	374	for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
	375	if (wep_encrypt_skb(tx, tx->u.tx.extra_frag[i]) < 0) {
	376	I802_DEBUG_INC(tx->local->
	377	tx_handlers_drop_wep);
	378	return TXRX_DROP;
	379	}
	380	}
	381	}
	382
	383	return TXRX_CONTINUE;
	384	}