[PATCH-mm 3/3] mac80211: Introduce struct michael_mic_ctx

Harvey Harrison
2008-04-16T18:30:33Z

Small holder for the michael_mic context allows the cleanup of
michael.c

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
---
net/mac80211/michael.c | 55 +++++++++++++++++++++++------------------------
net/mac80211/michael.h | 11 +++++++-
net/mac80211/wpa.c | 14 ++++++++++-
3 files changed, 48 insertions(+), 32 deletions(-)

diff --git a/net/mac80211/michael.c b/net/mac80211/michael.c
index 698d7b3..a9f5323 100644
--- a/net/mac80211/michael.c
+++ b/net/mac80211/michael.c
@@ -9,46 +9,48 @@

#include <linux/types.h>
#include <linux/bitops.h>
-#include <asm/byteorder.h>
#include <asm/unaligned.h>

#include "michael.h"

-static void michael_block(u32 val, u32 *l, u32 *r)
+static void michael_block(u32 val, struct michael_mic_ctx *mctx)
{
- *l ^= val;
- *r ^= rol32(*l, 17);
- *l += *r;
- *r ^= ((*l & 0xff00ff00) >> 8) | ((*l & 0x00ff00ff) << 8);
- *l += *r;
- *r ^= rol32(*l, 3);
- *l += *r;
- *r ^= ror32(*l, 2);
- *l += *r;
+ mctx->l ^= val;
+ mctx->r ^= rol32(mctx->l, 17);
+ mctx->l += mctx->r;
+ mctx->r ^= ((mctx->l & 0xff00ff00) >> 8) | ((mctx->l & 0x00ff00ff) << 8);
+ mctx->l += mctx->r;
+ mctx->r ^= rol32(mctx->l, 3);
+ mctx->l += mctx->r;
+ mctx->r ^= ror32(mctx->l, 2);
+ mctx->l += mctx->r;
}

-void michael_mic(u8 *key, u8 *da, u8 *sa, u8 priority,
- u8 *data, size_t data_len, u8 *mic)
+void michael_mic_init(struct michael_mic_ctx *mctx,
+ u8 *key, u8 *da, u8 *sa, u8 priority)
{
- u32 l, r, val;
- size_t block, blocks, left;
-
- l = get_unaligned_le32(key);
- r = get_unaligned_le32(key + 4);
+ mctx->l = get_unaligned_le32(key);
+ mctx->r = get_unaligned_le32(key + 4);

/* A pseudo header (DA, SA, Priority, 0, 0, 0) is used in Michael MIC
* calculation, but it is _not_ transmitted */
- michael_block(get_unaligned_le32(da), &l, &r);
- michael_block(get_unaligned_le16(da) | (get_unaligned_le16(sa) << 16), &l, &r);
- michael_block(get_unaligned_le32(sa + 2), &l, &r);
- michael_block(priority, &l, &r);
+ michael_block(get_unaligned_le32(da), mctx);
+ michael_block(get_unaligned_le16(da) | (get_unaligned_le16(sa) << 16), mctx);
+ michael_block(get_unaligned_le32(sa + 2), mctx);
+ michael_block(priority, mctx);
+}
+
+void michael_mic(struct michael_mic_ctx *mctx, u8 *data, size_t data_len)
+{
+ u32 val;
+ size_t block, blocks, left;

/* Real data */
blocks = data_len / 4;
left = data_len % 4;

for (block = 0; block < blocks; block++)
- michael_block(get_unaligned_le32(data + (block * 4)), &l, &r);
+ michael_block(get_unaligned_le32(data + (block * 4)), mctx);

/* Partial block of 0..3 bytes and padding: 0x5a + 4..7 zeros to make
* total length a multiple of 4. */
@@ -58,9 +60,6 @@ void michael_mic(u8 *key, u8 *da, u8 *sa, u8 priority,
left--;
val |= data[blocks * 4 + left];
}
- michael_block(val, &l, &r);
- michael_block(0, &l, &r);
-
- put_unaligned_le32(l, mic);
- put_unaligned_le32(r, mic + 4);
+ michael_block(val, mctx);
+ michael_block(0, mctx);
}
diff --git a/net/mac80211/michael.h b/net/mac80211/michael.h
index 2e6aeba..5976550 100644
--- a/net/mac80211/michael.h
+++ b/net/mac80211/michael.h
@@ -14,7 +14,14 @@

#define MICHAEL_MIC_LEN 8

-void michael_mic(u8 *key, u8 *da, u8 *sa, u8 priority,
- u8 *data, size_t data_len, u8 *mic);
+struct michael_mic_ctx {
+ u32 l, r;
+};
+
+extern void michael_mic_init(struct michael_mic_ctx *mctx,
+ u8 *key, u8 *da, u8 *sa, u8 priority);
+
+extern void michael_mic(struct michael_mic_ctx *mctx,
+ u8 *data, size_t data_len);

#endif /* MICHAEL_H */
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 45709ad..7db7b8e 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -12,6 +12,7 @@
#include <linux/skbuff.h>
#include <linux/compiler.h>
#include <net/mac80211.h>
+#include <asm/unaligned.h>

#include "ieee80211_i.h"
#include "michael.h"
@@ -79,6 +80,7 @@ ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
struct sk_buff *skb = tx->skb;
int authenticator;
int wpa_test = 0;
+ struct michael_mic_ctx mctx;

fc = tx->fc;

@@ -117,7 +119,10 @@ ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
key = &tx->key->conf.key[authenticator ? ALG_TKIP_TEMP_AUTH_TX_MIC_KEY :
ALG_TKIP_TEMP_AUTH_RX_MIC_KEY];
mic = skb_put(skb, MICHAEL_MIC_LEN);
- michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);
+ michael_mic_init(&mctx, key, da, sa, qos_tid & 0x0f);
+ michael_mic(&mctx, data, data_len);
+ put_unaligned_le32(mctx.l, mic);
+ put_unaligned_le32(mctx.r, mic + 4);

return TX_CONTINUE;
}
@@ -131,6 +136,7 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
u16 fc;
u8 mic[MICHAEL_MIC_LEN];
struct sk_buff *skb = rx->skb;
+ struct michael_mic_ctx mctx;
int authenticator = 1, wpa_test = 0;
DECLARE_MAC_BUF(mac);

@@ -159,7 +165,11 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
#endif
key = &rx->key->conf.key[authenticator ? ALG_TKIP_TEMP_AUTH_RX_MIC_KEY :
ALG_TKIP_TEMP_AUTH_TX_MIC_KEY];
- michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);
+ michael_mic_init(&mctx, key, da, sa, qos_tid & 0x0f);
+ michael_mic(&mctx, data, data_len);
+ put_unaligned_le32(mctx.l, mic);
+ put_unaligned_le32(mctx.r, mic + 4);
+
if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 || wpa_test) {
if (!(rx->flags & IEEE80211_RX_RA_MATCH))
return RX_DROP_UNUSABLE;
--
1.5.5.144.g3e42