mac80211: introduce struct michael_mic_ctx and static helpers

Replace the existing macro with a static function, significantly shrinks the
size of the produced object file.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/net/mac80211/michael.c b/net/mac80211/michael.c
index c1e5897fcf7ca2936756b87921d8926849809144..4e151e0caeb76bfb9d149a94ab863c4a753f380a 100644 (file)
--- a/net/mac80211/michael.c
+++ b/net/mac80211/michael.c
@@ -13,46 +13,52 @@
 
 #include "michael.h"
 
-#define michael_block(l, r) \
-do { \
-       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; \
-} while (0)
+static void michael_block(struct michael_mic_ctx *mctx, u32 val)
+{
+       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 void michael_mic_hdr(struct michael_mic_ctx *mctx,
+                           u8 *key, u8 *da, u8 *sa, u8 priority)
+{
+       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)
 {
-       u32 l, r, val;
+       u32 val;
        size_t block, blocks, left;
+       struct michael_mic_ctx mctx;
 
-       l = get_unaligned_le32(key);
-       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 */
-       l ^= get_unaligned_le32(da);
-       michael_block(l, r);
-       l ^= get_unaligned_le16(&da[4]) | (get_unaligned_le16(sa) << 16);
-       michael_block(l, r);
-       l ^= get_unaligned_le32(&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 ^= get_unaligned_le32(&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. */
@@ -62,11 +68,10 @@ 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);
 
-       put_unaligned_le32(l, mic);
-       put_unaligned_le32(r, mic + 4);
+       michael_block(&mctx, val);
+       michael_block(&mctx, 0);
+
+       put_unaligned_le32(mctx.l, mic);
+       put_unaligned_le32(mctx.r, mic + 4);
 }

diff --git a/net/mac80211/michael.h b/net/mac80211/michael.h
index 2e6aebabeea119a90038188dbbbdeb295a562c88..7d5707bf8843f2e4da9c95bcb7707dfd0a6ec9bb 100644 (file)
--- a/net/mac80211/michael.h
+++ b/net/mac80211/michael.h
@@ -14,6 +14,10 @@
 
 #define MICHAEL_MIC_LEN 8
 
+struct michael_mic_ctx {
+       u32 l, r;
+};
+
 void michael_mic(u8 *key, u8 *da, u8 *sa, u8 priority,
                 u8 *data, size_t data_len, u8 *mic);