From 1b19ca396621dcba573b20d4625526f5a460c886 Mon Sep 17 00:00:00 2001 From: Harvey Harrison Date: Wed, 14 May 2008 16:26:17 -0700 Subject: [PATCH] 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 Cc: "John W. Linville" Signed-off-by: Andrew Morton Signed-off-by: John W. Linville --- net/mac80211/michael.c | 75 ++++++++++++++++++++++-------------------- net/mac80211/michael.h | 4 +++ 2 files changed, 44 insertions(+), 35 deletions(-) diff --git a/net/mac80211/michael.c b/net/mac80211/michael.c index c1e5897fcf7c..4e151e0caeb7 100644 --- 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 2e6aebabeea1..7d5707bf8843 100644 --- 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); -- 2.20.1