mac80211: tkip.c use kernel-provided infrastructure
Use kernel-provided bit rotation and unaligned access infrastructure rather
than opencoding it.
Some minor spacing adjustments as well.
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/tkip.c b/net/mac80211/tkip.c
index 09093da..a7c3feb 100644
--- a/net/mac80211/tkip.c
+++ b/net/mac80211/tkip.c
@@ -8,23 +8,22 @@
*/
#include <linux/kernel.h>
+#include <linux/bitops.h>
#include <linux/types.h>
#include <linux/netdevice.h>
+#include <asm/unaligned.h>
#include <net/mac80211.h>
#include "key.h"
#include "tkip.h"
#include "wep.h"
-
-/* TKIP key mixing functions */
-
-
#define PHASE1_LOOP_COUNT 8
-
-/* 2-byte by 2-byte subset of the full AES S-box table; second part of this
- * table is identical to first part but byte-swapped */
+/*
+ * 2-byte by 2-byte subset of the full AES S-box table; second part of this
+ * table is identical to first part but byte-swapped
+ */
static const u16 tkip_sbox[256] =
{
0xC6A5, 0xF884, 0xEE99, 0xF68D, 0xFF0D, 0xD6BD, 0xDEB1, 0x9154,
@@ -61,53 +60,13 @@
0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A,
};
-
-static inline u16 Mk16(u8 x, u8 y)
+static u16 tkipS(u16 val)
{
- return ((u16) x << 8) | (u16) y;
+ return tkip_sbox[val & 0xff] ^ swab16(tkip_sbox[val >> 8]);
}
-
-static inline u8 Hi8(u16 v)
-{
- return v >> 8;
-}
-
-
-static inline u8 Lo8(u16 v)
-{
- return v & 0xff;
-}
-
-
-static inline u16 Hi16(u32 v)
-{
- return v >> 16;
-}
-
-
-static inline u16 Lo16(u32 v)
-{
- return v & 0xffff;
-}
-
-
-static inline u16 RotR1(u16 v)
-{
- return (v >> 1) | ((v & 0x0001) << 15);
-}
-
-
-static inline u16 tkip_S(u16 val)
-{
- u16 a = tkip_sbox[Hi8(val)];
-
- return tkip_sbox[Lo8(val)] ^ Hi8(a) ^ (Lo8(a) << 8);
-}
-
-
-
-/* P1K := Phase1(TA, TK, TSC)
+/*
+ * P1K := Phase1(TA, TK, TSC)
* TA = transmitter address (48 bits)
* TK = dot11DefaultKeyValue or dot11KeyMappingValue (128 bits)
* TSC = TKIP sequence counter (48 bits, only 32 msb bits used)
@@ -118,23 +77,22 @@
{
int i, j;
- p1k[0] = Lo16(tsc_IV32);
- p1k[1] = Hi16(tsc_IV32);
- p1k[2] = Mk16(ta[1], ta[0]);
- p1k[3] = Mk16(ta[3], ta[2]);
- p1k[4] = Mk16(ta[5], ta[4]);
+ p1k[0] = tsc_IV32 & 0xFFFF;
+ p1k[1] = tsc_IV32 >> 16;
+ p1k[2] = get_unaligned_le16(ta + 0);
+ p1k[3] = get_unaligned_le16(ta + 2);
+ p1k[4] = get_unaligned_le16(ta + 4);
for (i = 0; i < PHASE1_LOOP_COUNT; i++) {
j = 2 * (i & 1);
- p1k[0] += tkip_S(p1k[4] ^ Mk16(tk[ 1 + j], tk[ 0 + j]));
- p1k[1] += tkip_S(p1k[0] ^ Mk16(tk[ 5 + j], tk[ 4 + j]));
- p1k[2] += tkip_S(p1k[1] ^ Mk16(tk[ 9 + j], tk[ 8 + j]));
- p1k[3] += tkip_S(p1k[2] ^ Mk16(tk[13 + j], tk[12 + j]));
- p1k[4] += tkip_S(p1k[3] ^ Mk16(tk[ 1 + j], tk[ 0 + j])) + i;
+ p1k[0] += tkipS(p1k[4] ^ get_unaligned_le16(tk + 0 + j));
+ p1k[1] += tkipS(p1k[0] ^ get_unaligned_le16(tk + 4 + j));
+ p1k[2] += tkipS(p1k[1] ^ get_unaligned_le16(tk + 8 + j));
+ p1k[3] += tkipS(p1k[2] ^ get_unaligned_le16(tk + 12 + j));
+ p1k[4] += tkipS(p1k[3] ^ get_unaligned_le16(tk + 0 + j)) + i;
}
}
-
static void tkip_mixing_phase2(const u16 *p1k, const u8 *tk, u16 tsc_IV16,
u8 *rc4key)
{
@@ -148,31 +106,29 @@
ppk[4] = p1k[4];
ppk[5] = p1k[4] + tsc_IV16;
- ppk[0] += tkip_S(ppk[5] ^ Mk16(tk[ 1], tk[ 0]));
- ppk[1] += tkip_S(ppk[0] ^ Mk16(tk[ 3], tk[ 2]));
- ppk[2] += tkip_S(ppk[1] ^ Mk16(tk[ 5], tk[ 4]));
- ppk[3] += tkip_S(ppk[2] ^ Mk16(tk[ 7], tk[ 6]));
- ppk[4] += tkip_S(ppk[3] ^ Mk16(tk[ 9], tk[ 8]));
- ppk[5] += tkip_S(ppk[4] ^ Mk16(tk[11], tk[10]));
- ppk[0] += RotR1(ppk[5] ^ Mk16(tk[13], tk[12]));
- ppk[1] += RotR1(ppk[0] ^ Mk16(tk[15], tk[14]));
- ppk[2] += RotR1(ppk[1]);
- ppk[3] += RotR1(ppk[2]);
- ppk[4] += RotR1(ppk[3]);
- ppk[5] += RotR1(ppk[4]);
+ ppk[0] += tkipS(ppk[5] ^ get_unaligned_le16(tk + 0));
+ ppk[1] += tkipS(ppk[0] ^ get_unaligned_le16(tk + 2));
+ ppk[2] += tkipS(ppk[1] ^ get_unaligned_le16(tk + 4));
+ ppk[3] += tkipS(ppk[2] ^ get_unaligned_le16(tk + 6));
+ ppk[4] += tkipS(ppk[3] ^ get_unaligned_le16(tk + 8));
+ ppk[5] += tkipS(ppk[4] ^ get_unaligned_le16(tk + 10));
+ ppk[0] += ror16(ppk[5] ^ get_unaligned_le16(tk + 12), 1);
+ ppk[1] += ror16(ppk[0] ^ get_unaligned_le16(tk + 14), 1);
+ ppk[2] += ror16(ppk[1], 1);
+ ppk[3] += ror16(ppk[2], 1);
+ ppk[4] += ror16(ppk[3], 1);
+ ppk[5] += ror16(ppk[4], 1);
- rc4key[0] = Hi8(tsc_IV16);
- rc4key[1] = (Hi8(tsc_IV16) | 0x20) & 0x7f;
- rc4key[2] = Lo8(tsc_IV16);
- rc4key[3] = Lo8((ppk[5] ^ Mk16(tk[1], tk[0])) >> 1);
+ rc4key[0] = tsc_IV16 >> 8;
+ rc4key[1] = ((tsc_IV16 >> 8) | 0x20) & 0x7f;
+ rc4key[2] = tsc_IV16 & 0xFF;
+ rc4key[3] = ((ppk[5] ^ get_unaligned_le16(tk)) >> 1) & 0xFF;
- for (i = 0; i < 6; i++) {
- rc4key[4 + 2 * i] = Lo8(ppk[i]);
- rc4key[5 + 2 * i] = Hi8(ppk[i]);
- }
+ rc4key += 4;
+ for (i = 0; i < 6; i++)
+ put_unaligned_le16(ppk[i], rc4key + 2 * i);
}
-
/* Add TKIP IV and Ext. IV at @pos. @iv0, @iv1, and @iv2 are the first octets
* of the IV. Returns pointer to the octet following IVs (i.e., beginning of
* the packet payload). */
@@ -183,14 +139,10 @@
*pos++ = iv1;
*pos++ = iv2;
*pos++ = (key->conf.keyidx << 6) | (1 << 5) /* Ext IV */;
- *pos++ = key->u.tkip.iv32 & 0xff;
- *pos++ = (key->u.tkip.iv32 >> 8) & 0xff;
- *pos++ = (key->u.tkip.iv32 >> 16) & 0xff;
- *pos++ = (key->u.tkip.iv32 >> 24) & 0xff;
- return pos;
+ put_unaligned_le32(key->u.tkip.iv32, pos);
+ return pos + 4;
}
-
void ieee80211_tkip_gen_phase1key(struct ieee80211_key *key, u8 *ta,
u16 *phase1key)
{
@@ -228,10 +180,8 @@
u16 iv16;
u32 iv32;
- iv16 = data[hdr_len] << 8;
- iv16 += data[hdr_len + 2];
- iv32 = data[hdr_len + 4] | (data[hdr_len + 5] << 8) |
- (data[hdr_len + 6] << 16) | (data[hdr_len + 7] << 24);
+ iv16 = data[hdr_len + 2] | (data[hdr_len] << 8);
+ iv32 = get_unaligned_le32(data + hdr_len + 4);
#ifdef CONFIG_TKIP_DEBUG
printk(KERN_DEBUG "TKIP encrypt: iv16 = 0x%04x, iv32 = 0x%08x\n",
@@ -281,7 +231,6 @@
ieee80211_wep_encrypt_data(tfm, rc4key, 16, pos, payload_len);
}
-
/* Decrypt packet payload with TKIP using @key. @pos is a pointer to the
* beginning of the buffer containing IEEE 802.11 header payload, i.e.,
* including IV, Ext. IV, real data, Michael MIC, ICV. @payload_len is the
@@ -302,7 +251,7 @@
iv16 = (pos[0] << 8) | pos[2];
keyid = pos[3];
- iv32 = pos[4] | (pos[5] << 8) | (pos[6] << 16) | (pos[7] << 24);
+ iv32 = get_unaligned_le32(pos + 4);
pos += 8;
#ifdef CONFIG_TKIP_DEBUG
{
@@ -409,5 +358,3 @@
return res;
}
-
-