[deliverable/linux.git] / net / mac80211 / wpa.c

/*
 * Copyright 2002-2004, 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/slab.h>
#include <linux/skbuff.h>
#include <linux/compiler.h>
#include <linux/ieee80211.h>
#include <asm/unaligned.h>
#include <net/mac80211.h>

#include "ieee80211_i.h"
#include "michael.h"
#include "tkip.h"
#include "aes_ccm.h"
#include "wpa.h"

static int ieee80211_get_hdr_info(const struct sk_buff *skb, u8 **sa, u8 **da,
				  u8 *qos_tid, u8 **data, size_t *data_len)
{
	struct ieee80211_hdr *hdr;
	size_t hdrlen;
	__le16 fc;

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

	hdrlen = ieee80211_hdrlen(fc);

	*sa = ieee80211_get_SA(hdr);
	*da = ieee80211_get_DA(hdr);

	*data = skb->data + hdrlen;
	*data_len = skb->len - hdrlen;

	if (ieee80211_is_data_qos(fc))
		*qos_tid = (*ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK) | 0x80;
	else
		*qos_tid = 0;

	return skb->len < hdrlen ? -1 : 0;
}


ieee80211_tx_result
ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
{
	u8 *data, *sa, *da, *key, *mic, qos_tid, key_offset;
	size_t data_len;
	u16 fc;
	struct sk_buff *skb = tx->skb;
	int authenticator;
	int wpa_test = 0;
	int tail;

	fc = tx->fc;

	if (!tx->key || tx->key->conf.alg != ALG_TKIP || skb->len < 24 ||
	    !WLAN_FC_DATA_PRESENT(fc))
		return TX_CONTINUE;

	if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len))
		return TX_DROP;

	if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
	    !(tx->flags & IEEE80211_TX_FRAGMENTED) &&
	    !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) &&
	    !wpa_test) {
		/* hwaccel - with no need for preallocated room for Michael MIC
		 */
		return TX_CONTINUE;
	}

	tail = MICHAEL_MIC_LEN;
	if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
		tail += TKIP_ICV_LEN;

	if (WARN_ON(skb_tailroom(skb) < tail ||
		    skb_headroom(skb) < TKIP_IV_LEN))
		return TX_DROP;

#if 0
	authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */
#else
	authenticator = 1;
#endif
	/* At this point we know we're using ALG_TKIP. To get the MIC key
	 * we now will rely on the offset from the ieee80211_key_conf::key */
	key_offset = authenticator ?
		NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY :
		NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY;
	key = &tx->key->conf.key[key_offset];
	mic = skb_put(skb, MICHAEL_MIC_LEN);
	michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);

	return TX_CONTINUE;
}


ieee80211_rx_result
ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
{
	u8 *data, *sa, *da, *key = NULL, qos_tid, key_offset;
	size_t data_len;
	u16 fc;
	u8 mic[MICHAEL_MIC_LEN];
	struct sk_buff *skb = rx->skb;
	int authenticator = 1, wpa_test = 0;
	DECLARE_MAC_BUF(mac);

	fc = rx->fc;

	/*
	 * No way to verify the MIC if the hardware stripped it
	 */
	if (rx->status->flag & RX_FLAG_MMIC_STRIPPED)
		return RX_CONTINUE;

	if (!rx->key || rx->key->conf.alg != ALG_TKIP ||
	    !(rx->fc & IEEE80211_FCTL_PROTECTED) || !WLAN_FC_DATA_PRESENT(fc))
		return RX_CONTINUE;

	if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len)
	    || data_len < MICHAEL_MIC_LEN)
		return RX_DROP_UNUSABLE;

	data_len -= MICHAEL_MIC_LEN;

#if 0
	authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */
#else
	authenticator = 1;
#endif
	/* At this point we know we're using ALG_TKIP. To get the MIC key
	 * we now will rely on the offset from the ieee80211_key_conf::key */
	key_offset = authenticator ?
		NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY :
		NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY;
	key = &rx->key->conf.key[key_offset];
	michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);
	if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 || wpa_test) {
		if (!(rx->flags & IEEE80211_RX_RA_MATCH))
			return RX_DROP_UNUSABLE;

		mac80211_ev_michael_mic_failure(rx->dev, rx->key->conf.keyidx,
						(void *) skb->data);
		return RX_DROP_UNUSABLE;
	}

	/* remove Michael MIC from payload */
	skb_trim(skb, skb->len - MICHAEL_MIC_LEN);

	/* update IV in key information to be able to detect replays */
	rx->key->u.tkip.rx[rx->queue].iv32 = rx->tkip_iv32;
	rx->key->u.tkip.rx[rx->queue].iv16 = rx->tkip_iv16;

	return RX_CONTINUE;
}


static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	struct ieee80211_key *key = tx->key;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	unsigned int hdrlen;
	int len, tail;
	u8 *pos;

	info->control.icv_len = TKIP_ICV_LEN;
	info->control.iv_len = TKIP_IV_LEN;

	if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
	    !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
		/* hwaccel - with no need for preallocated room for IV/ICV */
		info->control.hw_key = &tx->key->conf;
		return 0;
	}

	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	len = skb->len - hdrlen;

	if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
		tail = 0;
	else
		tail = TKIP_ICV_LEN;

	if (WARN_ON(skb_tailroom(skb) < tail ||
		    skb_headroom(skb) < TKIP_IV_LEN))
		return -1;

	pos = skb_push(skb, TKIP_IV_LEN);
	memmove(pos, pos + TKIP_IV_LEN, hdrlen);
	pos += hdrlen;

	/* Increase IV for the frame */
	key->u.tkip.tx.iv16++;
	if (key->u.tkip.tx.iv16 == 0)
		key->u.tkip.tx.iv32++;

	if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
		/* hwaccel - with preallocated room for IV */
		ieee80211_tkip_add_iv(pos, key, key->u.tkip.tx.iv16);

		info->control.hw_key = &tx->key->conf;
		return 0;
	}

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

	hdr = (struct ieee80211_hdr *) skb->data;
	ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
				    key, pos, len, hdr->addr2);
	return 0;
}


ieee80211_tx_result
ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
{
	struct sk_buff *skb = tx->skb;

	ieee80211_tx_set_protected(tx);

	if (tkip_encrypt_skb(tx, skb) < 0)
		return TX_DROP;

	if (tx->extra_frag) {
		int i;
		for (i = 0; i < tx->num_extra_frag; i++) {
			if (tkip_encrypt_skb(tx, tx->extra_frag[i]) < 0)
				return TX_DROP;
		}
	}

	return TX_CONTINUE;
}


ieee80211_rx_result
ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
	int hdrlen, res, hwaccel = 0, wpa_test = 0;
	struct ieee80211_key *key = rx->key;
	struct sk_buff *skb = rx->skb;
	DECLARE_MAC_BUF(mac);

	hdrlen = ieee80211_hdrlen(hdr->frame_control);

	if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
		return RX_CONTINUE;

	if (!rx->sta || skb->len - hdrlen < 12)
		return RX_DROP_UNUSABLE;

	if (rx->status->flag & RX_FLAG_DECRYPTED) {
		if (rx->status->flag & RX_FLAG_IV_STRIPPED) {
			/*
			 * Hardware took care of all processing, including
			 * replay protection, and stripped the ICV/IV so
			 * we cannot do any checks here.
			 */
			return RX_CONTINUE;
		}

		/* let TKIP code verify IV, but skip decryption */
		hwaccel = 1;
	}

	res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
					  key, skb->data + hdrlen,
					  skb->len - hdrlen, rx->sta->addr,
					  hdr->addr1, hwaccel, rx->queue,
					  &rx->tkip_iv32,
					  &rx->tkip_iv16);
	if (res != TKIP_DECRYPT_OK || wpa_test)
		return RX_DROP_UNUSABLE;

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

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

	return RX_CONTINUE;
}


static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad,
				int encrypted)
{
	__le16 mask_fc;
	int a4_included;
	u8 qos_tid;
	u16 data_len, len_a;
	unsigned int hdrlen;
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;

	/*
	 * Mask FC: zero subtype b4 b5 b6
	 * Retry, PwrMgt, MoreData; set Protected
	 */
	mask_fc = hdr->frame_control;
	mask_fc &= ~cpu_to_le16(0x0070 | IEEE80211_FCTL_RETRY |
				IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
	mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);

	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	len_a = hdrlen - 2;
	a4_included = ieee80211_has_a4(hdr->frame_control);

	if (ieee80211_is_data_qos(hdr->frame_control))
		qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
	else
		qos_tid = 0;

	data_len = skb->len - hdrlen - CCMP_HDR_LEN;
	if (encrypted)
		data_len -= CCMP_MIC_LEN;

	/* First block, b_0 */
	b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
	/* Nonce: QoS Priority | A2 | PN */
	b_0[1] = qos_tid;
	memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
	memcpy(&b_0[8], pn, CCMP_PN_LEN);
	/* l(m) */
	put_unaligned_be16(data_len, &b_0[14]);

	/* AAD (extra authenticate-only data) / masked 802.11 header
	 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
	put_unaligned_be16(len_a, &aad[0]);
	put_unaligned(mask_fc, (__le16 *)&aad[2]);
	memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);

	/* Mask Seq#, leave Frag# */
	aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
	aad[23] = 0;

	if (a4_included) {
		memcpy(&aad[24], hdr->addr4, ETH_ALEN);
		aad[30] = qos_tid;
		aad[31] = 0;
	} else {
		memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
		aad[24] = qos_tid;
	}
}


static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
{
	hdr[0] = pn[5];
	hdr[1] = pn[4];
	hdr[2] = 0;
	hdr[3] = 0x20 | (key_id << 6);
	hdr[4] = pn[3];
	hdr[5] = pn[2];
	hdr[6] = pn[1];
	hdr[7] = pn[0];
}


static inline int ccmp_hdr2pn(u8 *pn, u8 *hdr)
{
	pn[0] = hdr[7];
	pn[1] = hdr[6];
	pn[2] = hdr[5];
	pn[3] = hdr[4];
	pn[4] = hdr[1];
	pn[5] = hdr[0];
	return (hdr[3] >> 6) & 0x03;
}


static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	struct ieee80211_key *key = tx->key;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	int hdrlen, len, tail;
	u8 *pos, *pn, *b_0, *aad, *scratch;
	int i;

	info->control.icv_len = CCMP_MIC_LEN;
	info->control.iv_len = CCMP_HDR_LEN;

	if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
	    !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
		/* hwaccel - with no need for preallocated room for CCMP "
		 * header or MIC fields */
		info->control.hw_key = &tx->key->conf;
		return 0;
	}

	scratch = key->u.ccmp.tx_crypto_buf;
	b_0 = scratch + 3 * AES_BLOCK_LEN;
	aad = scratch + 4 * AES_BLOCK_LEN;

	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	len = skb->len - hdrlen;

	if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
		tail = 0;
	else
		tail = CCMP_MIC_LEN;

	if (WARN_ON(skb_tailroom(skb) < tail ||
		    skb_headroom(skb) < CCMP_HDR_LEN))
		return -1;

	pos = skb_push(skb, CCMP_HDR_LEN);
	memmove(pos, pos + CCMP_HDR_LEN, hdrlen);
	hdr = (struct ieee80211_hdr *) pos;
	pos += hdrlen;

	/* PN = PN + 1 */
	pn = key->u.ccmp.tx_pn;

	for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
		pn[i]++;
		if (pn[i])
			break;
	}

	ccmp_pn2hdr(pos, pn, key->conf.keyidx);

	if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
		/* hwaccel - with preallocated room for CCMP header */
		info->control.hw_key = &tx->key->conf;
		return 0;
	}

	pos += CCMP_HDR_LEN;
	ccmp_special_blocks(skb, pn, b_0, aad, 0);
	ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, b_0, aad, pos, len,
				  pos, skb_put(skb, CCMP_MIC_LEN));

	return 0;
}


ieee80211_tx_result
ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx)
{
	struct sk_buff *skb = tx->skb;

	ieee80211_tx_set_protected(tx);

	if (ccmp_encrypt_skb(tx, skb) < 0)
		return TX_DROP;

	if (tx->extra_frag) {
		int i;
		for (i = 0; i < tx->num_extra_frag; i++) {
			if (ccmp_encrypt_skb(tx, tx->extra_frag[i]) < 0)
				return TX_DROP;
		}
	}

	return TX_CONTINUE;
}


ieee80211_rx_result
ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
	int hdrlen;
	struct ieee80211_key *key = rx->key;
	struct sk_buff *skb = rx->skb;
	u8 pn[CCMP_PN_LEN];
	int data_len;
	DECLARE_MAC_BUF(mac);

	hdrlen = ieee80211_hdrlen(hdr->frame_control);

	if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
		return RX_CONTINUE;

	data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
	if (!rx->sta || data_len < 0)
		return RX_DROP_UNUSABLE;

	if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
	    (rx->status->flag & RX_FLAG_IV_STRIPPED))
		return RX_CONTINUE;

	(void) ccmp_hdr2pn(pn, skb->data + hdrlen);

	if (memcmp(pn, key->u.ccmp.rx_pn[rx->queue], CCMP_PN_LEN) <= 0) {
		key->u.ccmp.replays++;
		return RX_DROP_UNUSABLE;
	}

	if (!(rx->status->flag & RX_FLAG_DECRYPTED)) {
		/* hardware didn't decrypt/verify MIC */
		u8 *scratch, *b_0, *aad;

		scratch = key->u.ccmp.rx_crypto_buf;
		b_0 = scratch + 3 * AES_BLOCK_LEN;
		aad = scratch + 4 * AES_BLOCK_LEN;

		ccmp_special_blocks(skb, pn, b_0, aad, 1);

		if (ieee80211_aes_ccm_decrypt(
			    key->u.ccmp.tfm, scratch, b_0, aad,
			    skb->data + hdrlen + CCMP_HDR_LEN, data_len,
			    skb->data + skb->len - CCMP_MIC_LEN,
			    skb->data + hdrlen + CCMP_HDR_LEN)) {
			return RX_DROP_UNUSABLE;
		}
	}

	memcpy(key->u.ccmp.rx_pn[rx->queue], pn, CCMP_PN_LEN);

	/* Remove CCMP header and MIC */
	skb_trim(skb, skb->len - CCMP_MIC_LEN);
	memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen);
	skb_pull(skb, CCMP_HDR_LEN);

	return RX_CONTINUE;
}
Commit	Line	Data
f0706e82 JB	1	/*
	2	* Copyright 2002-2004, Instant802 Networks, Inc.
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*/
	8
	9	#include <linux/netdevice.h>
	10	#include <linux/types.h>
	11	#include <linux/slab.h>
	12	#include <linux/skbuff.h>
	13	#include <linux/compiler.h>
f14df804 HH	14	#include <linux/ieee80211.h>
f14df804 HH	15	#include <asm/unaligned.h>
f0706e82	16	#include <net/mac80211.h>
eb063c17	17
f0706e82 JB	18	#include "ieee80211_i.h"
	19	#include "michael.h"
	20	#include "tkip.h"
	21	#include "aes_ccm.h"
	22	#include "wpa.h"
	23
	24	static int ieee80211_get_hdr_info(const struct sk_buff skb, u8 sa, u8 *da,
	25	u8 qos_tid, u8 data, size_t data_len)
	26	{
	27	struct ieee80211_hdr *hdr;
	28	size_t hdrlen;
d5184cac	29	__le16 fc;
f0706e82	30
d5184cac HH	31	hdr = (struct ieee80211_hdr *)skb->data;
d5184cac HH	32	fc = hdr->frame_control;
f0706e82	33
d5184cac HH	34	hdrlen = ieee80211_hdrlen(fc);
	35
	36	*sa = ieee80211_get_SA(hdr);
	37	*da = ieee80211_get_DA(hdr);
f0706e82 JB	38
	39	*data = skb->data + hdrlen;
	40	*data_len = skb->len - hdrlen;
	41
d5184cac	42	if (ieee80211_is_data_qos(fc))
73e1f7c8	43	qos_tid = (ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK) \| 0x80;
d5184cac	44	else
f0706e82 JB	45	*qos_tid = 0;
	46
	47	return skb->len < hdrlen ? -1 : 0;
	48	}
	49
	50
9ae54c84	51	ieee80211_tx_result
5cf121c3	52	ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
f0706e82	53	{
ffd7891d	54	u8 data, sa, da, key, *mic, qos_tid, key_offset;
f0706e82 JB	55	size_t data_len;
	56	u16 fc;
	57	struct sk_buff *skb = tx->skb;
	58	int authenticator;
	59	int wpa_test = 0;
23c0752a	60	int tail;
f0706e82 JB	61
	62	fc = tx->fc;
	63
8f20fc24	64	if (!tx->key \|\| tx->key->conf.alg != ALG_TKIP \|\| skb->len < 24 \|\|
f0706e82	65	!WLAN_FC_DATA_PRESENT(fc))
9ae54c84	66	return TX_CONTINUE;
f0706e82 JB	67
f0706e82 JB	68	if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len))
9ae54c84	69	return TX_DROP;
f0706e82	70
11a843b7	71	if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
5cf121c3	72	!(tx->flags & IEEE80211_TX_FRAGMENTED) &&
7848ba7d	73	!(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) &&
f0706e82 JB	74	!wpa_test) {
	75	/* hwaccel - with no need for preallocated room for Michael MIC
	76	*/
9ae54c84	77	return TX_CONTINUE;
f0706e82 JB	78	}
f0706e82 JB	79
23c0752a JB	80	tail = MICHAEL_MIC_LEN;
	81	if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
	82	tail += TKIP_ICV_LEN;
	83
	84	if (WARN_ON(skb_tailroom(skb) < tail \|\|
	85	skb_headroom(skb) < TKIP_IV_LEN))
	86	return TX_DROP;
f0706e82 JB	87
	88	#if 0
	89	authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */
	90	#else
	91	authenticator = 1;
	92	#endif
ffd7891d LR	93	/* At this point we know we're using ALG_TKIP. To get the MIC key
	94	* we now will rely on the offset from the ieee80211_key_conf::key */
	95	key_offset = authenticator ?
	96	NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY :
	97	NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY;
	98	key = &tx->key->conf.key[key_offset];
f0706e82 JB	99	mic = skb_put(skb, MICHAEL_MIC_LEN);
	100	michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);
	101
9ae54c84	102	return TX_CONTINUE;
f0706e82 JB	103	}
	104
	105
9ae54c84	106	ieee80211_rx_result
5cf121c3	107	ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
f0706e82	108	{
ffd7891d	109	u8 data, sa, da, key = NULL, qos_tid, key_offset;
f0706e82 JB	110	size_t data_len;
	111	u16 fc;
	112	u8 mic[MICHAEL_MIC_LEN];
	113	struct sk_buff *skb = rx->skb;
	114	int authenticator = 1, wpa_test = 0;
0795af57	115	DECLARE_MAC_BUF(mac);
f0706e82 JB	116
	117	fc = rx->fc;
	118
3017b80b JB	119	/*
	120	* No way to verify the MIC if the hardware stripped it
	121	*/
5cf121c3	122	if (rx->status->flag & RX_FLAG_MMIC_STRIPPED)
9ae54c84	123	return RX_CONTINUE;
f0706e82	124
8f20fc24	125	if (!rx->key \|\| rx->key->conf.alg != ALG_TKIP \|\|
f0706e82	126	!(rx->fc & IEEE80211_FCTL_PROTECTED) \|\| !WLAN_FC_DATA_PRESENT(fc))
9ae54c84	127	return RX_CONTINUE;
f0706e82	128
f0706e82 JB	129	if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len)
f0706e82 JB	130	\|\| data_len < MICHAEL_MIC_LEN)
e4c26add	131	return RX_DROP_UNUSABLE;
f0706e82 JB	132
	133	data_len -= MICHAEL_MIC_LEN;
	134
	135	#if 0
	136	authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */
	137	#else
	138	authenticator = 1;
	139	#endif
ffd7891d LR	140	/* At this point we know we're using ALG_TKIP. To get the MIC key
	141	* we now will rely on the offset from the ieee80211_key_conf::key */
	142	key_offset = authenticator ?
	143	NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY :
	144	NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY;
	145	key = &rx->key->conf.key[key_offset];
f0706e82 JB	146	michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);
f0706e82 JB	147	if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 \|\| wpa_test) {
5cf121c3	148	if (!(rx->flags & IEEE80211_RX_RA_MATCH))
e4c26add	149	return RX_DROP_UNUSABLE;
f0706e82	150
8f20fc24	151	mac80211_ev_michael_mic_failure(rx->dev, rx->key->conf.keyidx,
eb063c17	152	(void *) skb->data);
e4c26add	153	return RX_DROP_UNUSABLE;
f0706e82 JB	154	}
f0706e82 JB	155
f0706e82 JB	156	/* remove Michael MIC from payload */
	157	skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
	158
50741ae0	159	/* update IV in key information to be able to detect replays */
b0f76b33 HH	160	rx->key->u.tkip.rx[rx->queue].iv32 = rx->tkip_iv32;
b0f76b33 HH	161	rx->key->u.tkip.rx[rx->queue].iv16 = rx->tkip_iv16;
50741ae0	162
9ae54c84	163	return RX_CONTINUE;
f0706e82 JB	164	}
	165
	166
e039fa4a	167	static int tkip_encrypt_skb(struct ieee80211_tx_data tx, struct sk_buff skb)
f0706e82 JB	168	{
	169	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
	170	struct ieee80211_key *key = tx->key;
e039fa4a	171	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
d5184cac HH	172	unsigned int hdrlen;
d5184cac HH	173	int len, tail;
f0706e82 JB	174	u8 *pos;
f0706e82 JB	175
e039fa4a JB	176	info->control.icv_len = TKIP_ICV_LEN;
	177	info->control.iv_len = TKIP_IV_LEN;
	178
	179	if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
	180	!(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
	181	/* hwaccel - with no need for preallocated room for IV/ICV */
	182	info->control.hw_key = &tx->key->conf;
23c0752a	183	return 0;
e039fa4a JB	184	}
e039fa4a JB	185
d5184cac	186	hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82 JB	187	len = skb->len - hdrlen;
f0706e82 JB	188
11a843b7	189	if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
23c0752a	190	tail = 0;
11a843b7	191	else
23c0752a JB	192	tail = TKIP_ICV_LEN;
	193
	194	if (WARN_ON(skb_tailroom(skb) < tail \|\|
	195	skb_headroom(skb) < TKIP_IV_LEN))
	196	return -1;
f0706e82 JB	197
	198	pos = skb_push(skb, TKIP_IV_LEN);
	199	memmove(pos, pos + TKIP_IV_LEN, hdrlen);
	200	pos += hdrlen;
	201
	202	/* Increase IV for the frame */
b0f76b33 HH	203	key->u.tkip.tx.iv16++;
	204	if (key->u.tkip.tx.iv16 == 0)
	205	key->u.tkip.tx.iv32++;
f0706e82	206
11a843b7	207	if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
f0706e82	208	/* hwaccel - with preallocated room for IV */
c801242c	209	ieee80211_tkip_add_iv(pos, key, key->u.tkip.tx.iv16);
f0706e82	210
e039fa4a	211	info->control.hw_key = &tx->key->conf;
f0706e82 JB	212	return 0;
	213	}
	214
	215	/* Add room for ICV */
	216	skb_put(skb, TKIP_ICV_LEN);
	217
	218	hdr = (struct ieee80211_hdr *) skb->data;
	219	ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
	220	key, pos, len, hdr->addr2);
	221	return 0;
	222	}
	223
	224
9ae54c84	225	ieee80211_tx_result
5cf121c3	226	ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
f0706e82	227	{
f0706e82	228	struct sk_buff *skb = tx->skb;
f0706e82	229
5cf121c3	230	ieee80211_tx_set_protected(tx);
f0706e82	231
e039fa4a	232	if (tkip_encrypt_skb(tx, skb) < 0)
9ae54c84	233	return TX_DROP;
f0706e82	234
5cf121c3	235	if (tx->extra_frag) {
f0706e82	236	int i;
5cf121c3	237	for (i = 0; i < tx->num_extra_frag; i++) {
e039fa4a	238	if (tkip_encrypt_skb(tx, tx->extra_frag[i]) < 0)
9ae54c84	239	return TX_DROP;
f0706e82 JB	240	}
	241	}
	242
9ae54c84	243	return TX_CONTINUE;
f0706e82 JB	244	}
	245
	246
9ae54c84	247	ieee80211_rx_result
5cf121c3	248	ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
f0706e82 JB	249	{
f0706e82 JB	250	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) rx->skb->data;
f0706e82 JB	251	int hdrlen, res, hwaccel = 0, wpa_test = 0;
	252	struct ieee80211_key *key = rx->key;
	253	struct sk_buff *skb = rx->skb;
0795af57	254	DECLARE_MAC_BUF(mac);
f0706e82	255
d5184cac	256	hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82	257
4f0d18e2	258	if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
9ae54c84	259	return RX_CONTINUE;
f0706e82 JB	260
f0706e82 JB	261	if (!rx->sta \|\| skb->len - hdrlen < 12)
e4c26add	262	return RX_DROP_UNUSABLE;
f0706e82	263
5cf121c3 JB	264	if (rx->status->flag & RX_FLAG_DECRYPTED) {
5cf121c3 JB	265	if (rx->status->flag & RX_FLAG_IV_STRIPPED) {
7848ba7d JB	266	/*
	267	* Hardware took care of all processing, including
	268	* replay protection, and stripped the ICV/IV so
	269	* we cannot do any checks here.
	270	*/
9ae54c84	271	return RX_CONTINUE;
f0706e82 JB	272	}
	273
	274	/* let TKIP code verify IV, but skip decryption */
	275	hwaccel = 1;
	276	}
	277
	278	res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
	279	key, skb->data + hdrlen,
	280	skb->len - hdrlen, rx->sta->addr,
9ae4fda3	281	hdr->addr1, hwaccel, rx->queue,
5cf121c3 JB	282	&rx->tkip_iv32,
5cf121c3 JB	283	&rx->tkip_iv16);
f4ea83dd	284	if (res != TKIP_DECRYPT_OK \|\| wpa_test)
e4c26add	285	return RX_DROP_UNUSABLE;
f0706e82 JB	286
	287	/* Trim ICV */
	288	skb_trim(skb, skb->len - TKIP_ICV_LEN);
	289
	290	/* Remove IV */
	291	memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen);
	292	skb_pull(skb, TKIP_IV_LEN);
	293
9ae54c84	294	return RX_CONTINUE;
f0706e82 JB	295	}
	296
	297
	298	static void ccmp_special_blocks(struct sk_buff skb, u8 pn, u8 b_0, u8 aad,
	299	int encrypted)
	300	{
f14df804 HH	301	__le16 mask_fc;
	302	int a4_included;
	303	u8 qos_tid;
	304	u16 data_len, len_a;
	305	unsigned int hdrlen;
	306	struct ieee80211_hdr hdr = (struct ieee80211_hdr )skb->data;
f0706e82	307
f14df804 HH	308	/*
	309	* Mask FC: zero subtype b4 b5 b6
	310	* Retry, PwrMgt, MoreData; set Protected
	311	*/
	312	mask_fc = hdr->frame_control;
	313	mask_fc &= ~cpu_to_le16(0x0070 \| IEEE80211_FCTL_RETRY \|
	314	IEEE80211_FCTL_PM \| IEEE80211_FCTL_MOREDATA);
	315	mask_fc \|= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
	316
	317	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	318	len_a = hdrlen - 2;
	319	a4_included = ieee80211_has_a4(hdr->frame_control);
f0706e82	320
f14df804 HH	321	if (ieee80211_is_data_qos(hdr->frame_control))
	322	qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
	323	else
	324	qos_tid = 0;
	325
	326	data_len = skb->len - hdrlen - CCMP_HDR_LEN;
	327	if (encrypted)
	328	data_len -= CCMP_MIC_LEN;
	329
	330	/* First block, b_0 */
f0706e82 JB	331	b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
	332	/* Nonce: QoS Priority \| A2 \| PN */
	333	b_0[1] = qos_tid;
73e1f7c8	334	memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
f0706e82 JB	335	memcpy(&b_0[8], pn, CCMP_PN_LEN);
f0706e82 JB	336	/* l(m) */
f14df804	337	put_unaligned_be16(data_len, &b_0[14]);
f0706e82 JB	338
	339	/* AAD (extra authenticate-only data) / masked 802.11 header
	340	* FC \| A1 \| A2 \| A3 \| SC \| [A4] \| [QC] */
f14df804 HH	341	put_unaligned_be16(len_a, &aad[0]);
f14df804 HH	342	put_unaligned(mask_fc, (__le16 *)&aad[2]);
73e1f7c8	343	memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
f0706e82 JB	344
	345	/* Mask Seq#, leave Frag# */
	346	aad[22] = ((u8 ) &hdr->seq_ctrl) & 0x0f;
	347	aad[23] = 0;
f14df804	348
f0706e82	349	if (a4_included) {
73e1f7c8	350	memcpy(&aad[24], hdr->addr4, ETH_ALEN);
f14df804	351	aad[30] = qos_tid;
f0706e82	352	aad[31] = 0;
f14df804	353	} else {
73e1f7c8	354	memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
f14df804	355	aad[24] = qos_tid;
f0706e82 JB	356	}
	357	}
	358
	359
	360	static inline void ccmp_pn2hdr(u8 hdr, u8 pn, int key_id)
	361	{
	362	hdr[0] = pn[5];
	363	hdr[1] = pn[4];
	364	hdr[2] = 0;
	365	hdr[3] = 0x20 \| (key_id << 6);
	366	hdr[4] = pn[3];
	367	hdr[5] = pn[2];
	368	hdr[6] = pn[1];
	369	hdr[7] = pn[0];
	370	}
	371
	372
	373	static inline int ccmp_hdr2pn(u8 pn, u8 hdr)
	374	{
	375	pn[0] = hdr[7];
	376	pn[1] = hdr[6];
	377	pn[2] = hdr[5];
	378	pn[3] = hdr[4];
	379	pn[4] = hdr[1];
	380	pn[5] = hdr[0];
	381	return (hdr[3] >> 6) & 0x03;
	382	}
	383
	384
e039fa4a	385	static int ccmp_encrypt_skb(struct ieee80211_tx_data tx, struct sk_buff skb)
f0706e82 JB	386	{
	387	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
	388	struct ieee80211_key *key = tx->key;
e039fa4a	389	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
23c0752a	390	int hdrlen, len, tail;
f0706e82 JB	391	u8 pos, pn, b_0, aad, *scratch;
	392	int i;
	393
e039fa4a JB	394	info->control.icv_len = CCMP_MIC_LEN;
	395	info->control.iv_len = CCMP_HDR_LEN;
	396
	397	if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
	398	!(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
	399	/* hwaccel - with no need for preallocated room for CCMP "
	400	* header or MIC fields */
	401	info->control.hw_key = &tx->key->conf;
23c0752a	402	return 0;
e039fa4a JB	403	}
e039fa4a JB	404
f0706e82 JB	405	scratch = key->u.ccmp.tx_crypto_buf;
	406	b_0 = scratch + 3 * AES_BLOCK_LEN;
	407	aad = scratch + 4 * AES_BLOCK_LEN;
	408
d5184cac	409	hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82 JB	410	len = skb->len - hdrlen;
f0706e82 JB	411
11a843b7	412	if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
23c0752a	413	tail = 0;
11a843b7	414	else
23c0752a JB	415	tail = CCMP_MIC_LEN;
	416
	417	if (WARN_ON(skb_tailroom(skb) < tail \|\|
	418	skb_headroom(skb) < CCMP_HDR_LEN))
	419	return -1;
f0706e82 JB	420
	421	pos = skb_push(skb, CCMP_HDR_LEN);
	422	memmove(pos, pos + CCMP_HDR_LEN, hdrlen);
	423	hdr = (struct ieee80211_hdr *) pos;
	424	pos += hdrlen;
	425
	426	/* PN = PN + 1 */
	427	pn = key->u.ccmp.tx_pn;
	428
	429	for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
	430	pn[i]++;
	431	if (pn[i])
	432	break;
	433	}
	434
8f20fc24	435	ccmp_pn2hdr(pos, pn, key->conf.keyidx);
f0706e82	436
11a843b7	437	if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
f0706e82	438	/* hwaccel - with preallocated room for CCMP header */
e039fa4a	439	info->control.hw_key = &tx->key->conf;
f0706e82 JB	440	return 0;
	441	}
	442
	443	pos += CCMP_HDR_LEN;
	444	ccmp_special_blocks(skb, pn, b_0, aad, 0);
	445	ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, b_0, aad, pos, len,
	446	pos, skb_put(skb, CCMP_MIC_LEN));
	447
	448	return 0;
	449	}
	450
	451
9ae54c84	452	ieee80211_tx_result
5cf121c3	453	ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx)
f0706e82	454	{
f0706e82	455	struct sk_buff *skb = tx->skb;
f0706e82	456
5cf121c3	457	ieee80211_tx_set_protected(tx);
f0706e82	458
e039fa4a	459	if (ccmp_encrypt_skb(tx, skb) < 0)
9ae54c84	460	return TX_DROP;
f0706e82	461
5cf121c3	462	if (tx->extra_frag) {
f0706e82	463	int i;
5cf121c3	464	for (i = 0; i < tx->num_extra_frag; i++) {
e039fa4a	465	if (ccmp_encrypt_skb(tx, tx->extra_frag[i]) < 0)
9ae54c84	466	return TX_DROP;
f0706e82 JB	467	}
	468	}
	469
9ae54c84	470	return TX_CONTINUE;
f0706e82 JB	471	}
	472
	473
9ae54c84	474	ieee80211_rx_result
5cf121c3	475	ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
f0706e82 JB	476	{
f0706e82 JB	477	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) rx->skb->data;
f0706e82 JB	478	int hdrlen;
	479	struct ieee80211_key *key = rx->key;
	480	struct sk_buff *skb = rx->skb;
	481	u8 pn[CCMP_PN_LEN];
	482	int data_len;
0795af57	483	DECLARE_MAC_BUF(mac);
f0706e82	484
d5184cac	485	hdrlen = ieee80211_hdrlen(hdr->frame_control);
f0706e82	486
4f0d18e2	487	if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
9ae54c84	488	return RX_CONTINUE;
f0706e82 JB	489
	490	data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
	491	if (!rx->sta \|\| data_len < 0)
e4c26add	492	return RX_DROP_UNUSABLE;
f0706e82	493
5cf121c3 JB	494	if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
5cf121c3 JB	495	(rx->status->flag & RX_FLAG_IV_STRIPPED))
9ae54c84	496	return RX_CONTINUE;
f0706e82 JB	497
	498	(void) ccmp_hdr2pn(pn, skb->data + hdrlen);
	499
5cf121c3	500	if (memcmp(pn, key->u.ccmp.rx_pn[rx->queue], CCMP_PN_LEN) <= 0) {
f0706e82	501	key->u.ccmp.replays++;
e4c26add	502	return RX_DROP_UNUSABLE;
f0706e82 JB	503	}
f0706e82 JB	504
5cf121c3	505	if (!(rx->status->flag & RX_FLAG_DECRYPTED)) {
7848ba7d	506	/* hardware didn't decrypt/verify MIC */
f0706e82 JB	507	u8 scratch, b_0, *aad;
	508
	509	scratch = key->u.ccmp.rx_crypto_buf;
	510	b_0 = scratch + 3 * AES_BLOCK_LEN;
	511	aad = scratch + 4 * AES_BLOCK_LEN;
	512
	513	ccmp_special_blocks(skb, pn, b_0, aad, 1);
	514
	515	if (ieee80211_aes_ccm_decrypt(
	516	key->u.ccmp.tfm, scratch, b_0, aad,
	517	skb->data + hdrlen + CCMP_HDR_LEN, data_len,
	518	skb->data + skb->len - CCMP_MIC_LEN,
	519	skb->data + hdrlen + CCMP_HDR_LEN)) {
e4c26add	520	return RX_DROP_UNUSABLE;
f0706e82 JB	521	}
	522	}
	523
5cf121c3	524	memcpy(key->u.ccmp.rx_pn[rx->queue], pn, CCMP_PN_LEN);
f0706e82 JB	525
	526	/* Remove CCMP header and MIC */
	527	skb_trim(skb, skb->len - CCMP_MIC_LEN);
	528	memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen);
	529	skb_pull(skb, CCMP_HDR_LEN);
	530
9ae54c84	531	return RX_CONTINUE;
f0706e82	532	}