Commit 8e8862b7 authored by Harvey Harrison's avatar Harvey Harrison Committed by John W. Linville
Browse files

mac80211: remove ieee80211_get_hdr_info 



Do the check for sufficient skb->len explicitly and pass a pointer
to the struct ieee80211_hdr directly to the michael_mic calculation.

Signed-off-by: default avatarHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent f14df804

net/mac80211/michael.c

+15 −5
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
 */

#include <linux/types.h>

#include <linux/bitops.h>

#include <linux/ieee80211.h>

#include <asm/unaligned.h>



#include "michael.h"
@@ -26,9 +27,18 @@ static void michael_block(struct michael_mic_ctx *mctx, u32 val) 
	mctx->l += mctx->r;

}



static void michael_mic_hdr(struct michael_mic_ctx *mctx,

			const u8 *key, const u8 *da, const u8 *sa, u8 priority)

static void michael_mic_hdr(struct michael_mic_ctx *mctx, const u8 *key,

			    struct ieee80211_hdr *hdr)

{

	u8 *da, *sa, tid;



	da = ieee80211_get_DA(hdr);

	sa = ieee80211_get_SA(hdr);

	if (ieee80211_is_data_qos(hdr->frame_control))

		tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;

	else

		tid = 0;



	mctx->l = get_unaligned_le32(key);

	mctx->r = get_unaligned_le32(key + 4);
@@ -40,17 +50,17 @@ static void michael_mic_hdr(struct michael_mic_ctx *mctx, 
	michael_block(mctx, get_unaligned_le16(&da[4]) |

			    (get_unaligned_le16(sa) << 16));

	michael_block(mctx, get_unaligned_le32(&sa[2]));

	michael_block(mctx, priority);

	michael_block(mctx, tid);

}



void michael_mic(const u8 *key, const u8 *da, const u8 *sa, u8 priority,

void michael_mic(const u8 *key, struct ieee80211_hdr *hdr,

		 const u8 *data, size_t data_len, u8 *mic)

{

	u32 val;

	size_t block, blocks, left;

	struct michael_mic_ctx mctx;



	michael_mic_hdr(&mctx, key, da, sa, priority);

	michael_mic_hdr(&mctx, key, hdr);



	/* Real data */

	blocks = data_len / 4;

net/mac80211/michael.h

+1 −1
Original line number Diff line number Diff line
@@ -18,7 +18,7 @@ struct michael_mic_ctx { 
	u32 l, r;

};



void michael_mic(const u8 *key, const u8 *da, const u8 *sa, u8 priority,

void michael_mic(const u8 *key, struct ieee80211_hdr *hdr,

		 const u8 *data, size_t data_len, u8 *mic);



#endif /* MICHAEL_H */

net/mac80211/wpa.c

+19 −35
Original line number Diff line number Diff line
@@ -21,38 +21,13 @@ 
#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;

	u8 *data, *key, *mic, key_offset;

	size_t data_len;

	unsigned int hdrlen;

	struct ieee80211_hdr *hdr;

	u16 fc;

	struct sk_buff *skb = tx->skb;

	int authenticator;
@@ -65,9 +40,14 @@ ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx) 
	    !WLAN_FC_DATA_PRESENT(fc))

		return TX_CONTINUE;



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

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

	hdrlen = ieee80211_hdrlen(hdr->frame_control);

	if (skb->len < hdrlen)

		return TX_DROP;



	data = skb->data + hdrlen;

	data_len = skb->len - hdrlen;



	if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&

	    !(tx->flags & IEEE80211_TX_FRAGMENTED) &&

	    !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) &&
@@ -97,7 +77,7 @@ ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx) 
		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);

	michael_mic(key, hdr, data, data_len, mic);



	return TX_CONTINUE;

}
@@ -106,8 +86,10 @@ ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx) 
ieee80211_rx_result

ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)

{

	u8 *data, *sa, *da, *key = NULL, qos_tid, key_offset;

	u8 *data, *key = NULL, key_offset;

	size_t data_len;

	unsigned int hdrlen;

	struct ieee80211_hdr *hdr;

	u16 fc;

	u8 mic[MICHAEL_MIC_LEN];

	struct sk_buff *skb = rx->skb;
@@ -126,11 +108,13 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) 
	    !(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)

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

	hdrlen = ieee80211_hdrlen(hdr->frame_control);

	if (skb->len < hdrlen + MICHAEL_MIC_LEN)

		return RX_DROP_UNUSABLE;



	data_len -= MICHAEL_MIC_LEN;

	data = skb->data + hdrlen;

	data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;



#if 0

	authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */
@@ -143,7 +127,7 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) 
		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);

	michael_mic(key, hdr, 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;