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Diffstat (limited to 'net/mac80211/michael.c')
-rw-r--r--net/mac80211/michael.c106
1 files changed, 39 insertions, 67 deletions
diff --git a/net/mac80211/michael.c b/net/mac80211/michael.c
index 0f844f7895f..1fcdf38cf60 100644
--- a/net/mac80211/michael.c
+++ b/net/mac80211/michael.c
@@ -6,85 +6,58 @@
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
-
#include <linux/types.h>
+#include <linux/bitops.h>
+#include <asm/unaligned.h>
#include "michael.h"
-static inline u32 rotr(u32 val, int bits)
-{
- return (val >> bits) | (val << (32 - bits));
-}
-
-
-static inline u32 rotl(u32 val, int bits)
-{
- return (val << bits) | (val >> (32 - bits));
-}
-
-
-static inline u32 xswap(u32 val)
-{
- return ((val & 0xff00ff00) >> 8) | ((val & 0x00ff00ff) << 8);
-}
-
-
-#define michael_block(l, r) \
-do { \
- r ^= rotl(l, 17); \
- l += r; \
- r ^= xswap(l); \
- l += r; \
- r ^= rotl(l, 3); \
- l += r; \
- r ^= rotr(l, 2); \
- l += r; \
-} while (0)
-
-
-static inline u32 michael_get32(u8 *data)
+static void michael_block(struct michael_mic_ctx *mctx, u32 val)
{
- return data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
+ 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;
}
-
-static inline void michael_put32(u32 val, u8 *data)
+static void michael_mic_hdr(struct michael_mic_ctx *mctx,
+ const u8 *key, const u8 *da, const u8 *sa, u8 priority)
{
- data[0] = val & 0xff;
- data[1] = (val >> 8) & 0xff;
- data[2] = (val >> 16) & 0xff;
- data[3] = (val >> 24) & 0xff;
+ 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(mctx, get_unaligned_le32(da));
+ 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);
}
-
-void michael_mic(u8 *key, u8 *da, u8 *sa, u8 priority,
- u8 *data, size_t data_len, u8 *mic)
+void michael_mic(const u8 *key, const u8 *da, const u8 *sa, u8 priority,
+ const u8 *data, size_t data_len, u8 *mic)
{
- u32 l, r, val;
+ u32 val;
size_t block, blocks, left;
+ struct michael_mic_ctx mctx;
- l = michael_get32(key);
- r = michael_get32(key + 4);
-
- /* A pseudo header (DA, SA, Priority, 0, 0, 0) is used in Michael MIC
- * calculation, but it is _not_ transmitted */
- l ^= michael_get32(da);
- michael_block(l, r);
- l ^= da[4] | (da[5] << 8) | (sa[0] << 16) | (sa[1] << 24);
- michael_block(l, r);
- l ^= michael_get32(&sa[2]);
- michael_block(l, r);
- l ^= priority;
- michael_block(l, r);
+ michael_mic_hdr(&mctx, key, da, sa, priority);
/* Real data */
blocks = data_len / 4;
left = data_len % 4;
- for (block = 0; block < blocks; block++) {
- l ^= michael_get32(&data[block * 4]);
- michael_block(l, r);
- }
+ for (block = 0; block < blocks; block++)
+ michael_block(&mctx, get_unaligned_le32(&data[block * 4]));
/* Partial block of 0..3 bytes and padding: 0x5a + 4..7 zeros to make
* total length a multiple of 4. */
@@ -94,11 +67,10 @@ void michael_mic(u8 *key, u8 *da, u8 *sa, u8 priority,
left--;
val |= data[blocks * 4 + left];
}
- l ^= val;
- michael_block(l, r);
- /* last block is zero, so l ^ 0 = l */
- michael_block(l, r);
- michael_put32(l, mic);
- michael_put32(r, mic + 4);
+ michael_block(&mctx, val);
+ michael_block(&mctx, 0);
+
+ put_unaligned_le32(mctx.l, mic);
+ put_unaligned_le32(mctx.r, mic + 4);
}