mac80211: tkip.c use a local struct tkip_ctx in ieee80211_get_tkip_key

	struct ieee80211_key *key = (struct ieee80211_key *)

			container_of(keyconf, struct ieee80211_key, conf);

	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;

	u8 *data = (u8 *) hdr;

	u16 fc = le16_to_cpu(hdr->frame_control);

	int hdr_len = ieee80211_get_hdrlen(fc);

	u8 *tk = &key->conf.key[ALG_TKIP_TEMP_ENCR_KEY];

	u8 *ta = hdr->addr2;

	u8 *data;

	const u8 *tk;

	struct tkip_ctx *ctx;

	u16 iv16;

	u32 iv32;

	iv16 = data[hdr_len + 2] | (data[hdr_len] << 8);

	iv32 = get_unaligned_le32(data + hdr_len + 4);

	data = (u8 *)hdr + ieee80211_hdrlen(hdr->frame_control);

	iv16 = data[2] | (data[0] << 8);

	iv32 = get_unaligned_le32(&data[4]);

	tk = &key->conf.key[ALG_TKIP_TEMP_ENCR_KEY];

	ctx = &key->u.tkip.tx;

#ifdef CONFIG_TKIP_DEBUG

	printk(KERN_DEBUG "TKIP encrypt: iv16 = 0x%04x, iv32 = 0x%08x\n",

			iv16, iv32);

	if (iv32 != key->u.tkip.tx.iv32) {

	if (iv32 != ctx->iv32) {

		printk(KERN_DEBUG "skb: iv32 = 0x%08x key: iv32 = 0x%08x\n",

			iv32, key->u.tkip.tx.iv32);

			iv32, ctx->iv32);

		printk(KERN_DEBUG "Wrap around of iv16 in the middle of a "

			"fragmented packet\n");

	}

	/* Update the p1k only when the iv16 in the packet wraps around, this

	 * might occur after the wrap around of iv16 in the key in case of

	 * fragmented packets. */

	if (iv16 == 0 || !key->u.tkip.tx.initialized)

		tkip_mixing_phase1(tk, &key->u.tkip.tx, ta, iv32);

	if (iv16 == 0 || !ctx->initialized)

		tkip_mixing_phase1(tk, ctx, hdr->addr2, iv32);

	if (type == IEEE80211_TKIP_P1_KEY) {

		memcpy(outkey, key->u.tkip.tx.p1k, sizeof(u16) * 5);

		memcpy(outkey, ctx->p1k, sizeof(u16) * 5);

		return;

	}

	tkip_mixing_phase2(tk, &key->u.tkip.tx, iv16, outkey);

	tkip_mixing_phase2(tk, ctx, iv16, outkey);

}

EXPORT_SYMBOL(ieee80211_get_tkip_key);