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mac80211: use kernel-provided bit rotation/byteordering

PATCH In review Harvey Harrison 2 participants 3 messages Mar 8, 2008 – Mar 11, 2008

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#0 lore raw

PATCH 1/5 mac80211: use kernel-provided bit rotation/byteordering

---
Perhaps a bit too fine-grained of a patch series, but each one should be pretty easily reviewable.

 include/linux/bitops.h |   40 ++++++++++++++++++++++++++++++++++++++++
 net/mac80211/michael.c |   28 ++++++----------------------
 net/mac80211/tkip.c    |   20 ++++++--------------
 3 files changed, 52 insertions(+), 36 deletions(-)
include/linux/bitops.h +40 -0
index 69c1edb..40d5473 100644
@@ -65,6 +65,46 @@ static inline __u32 ror32(__u32 word, unsigned int shift)
 	return (word >> shift) | (word << (32 - shift));
 }
 
+/**
+ * rol16 - rotate a 16-bit value left
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline __u16 rol16(__u16 word, unsigned int shift)
+{
+	return (word << shift) | (word >> (16 - shift));
+}
+
+/**
+ * ror16 - rotate a 16-bit value right
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline __u16 ror16(__u16 word, unsigned int shift)
+{
+	return (word >> shift) | (word << (16 - shift));
+}
+
+/**
+ * rol8 - rotate an 8-bit value left
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline __u8 rol8(__u8 word, unsigned int shift)
+{
+	return (word << shift) | (word >> (8 - shift));
+}
+
+/**
+ * ror8 - rotate an 8-bit value right
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline __u8 ror8(__u8 word, unsigned int shift)
+{
+	return (word >> shift) | (word << (8 - shift));
+}
+
 static inline unsigned fls_long(unsigned long l)
 {
 	if (sizeof(l) == 4)
net/mac80211/michael.c +6 -22
index 0f844f7..1a1871f 100644
@@ -7,53 +7,37 @@
  * published by the Free Software Foundation.
  */
 
-#include <linux/types.h>
+#include <linux/kernel.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); \
+	r ^= rol32(l, 17); \
 	l += r; \
 	r ^= xswap(l); \
 	l += r; \
-	r ^= rotl(l, 3); \
+	r ^= rol32(l, 3); \
 	l += r; \
-	r ^= rotr(l, 2); \
+	r ^= ror32(l, 2); \
 	l += r; \
 } while (0)
 
 
 static inline u32 michael_get32(u8 *data)
 {
-	return data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
+	return le32_to_cpup((__le32 *)data);
 }
 
 
 static inline void michael_put32(u32 val, u8 *data)
 {
-	data[0] = val & 0xff;
-	data[1] = (val >> 8) & 0xff;
-	data[2] = (val >> 16) & 0xff;
-	data[3] = (val >> 24) & 0xff;
+	*((u32 *)data) = cpu_to_le32(val);
 }
 
 
net/mac80211/tkip.c +6 -14
index 3abe194..229b4b4 100644
@@ -8,7 +8,6 @@
  */
 
 #include <linux/kernel.h>
-#include <linux/types.h>
 #include <linux/netdevice.h>
 
 #include <net/mac80211.h>
@@ -91,13 +90,6 @@ 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)];
@@ -154,12 +146,12 @@ static void tkip_mixing_phase2(const u16 *p1k, const u8 *tk, u16 tsc_IV16,
 	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] += ror16(ppk[5] ^ Mk16(tk[13], tk[12]), 1);
+	ppk[1] += ror16(ppk[0] ^ Mk16(tk[15], 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;
Signature · 1 line
1.5.4.GIT
maintainer
#1 lore raw
Quoted 5 lines
 include/linux/bitops.h |   40 ++++++++++++++++++++++++++++++++++++++++

+++ b/include/linux/bitops.h

include/linux/bitops.h static inline __u32 ror32(__u32 word, unsigned int shift) · line 73

Quoted 9 lines
include/linux/bitops.h +6 -0
@@ -65,6 +65,46 @@ static inline __u32 ror32(__u32 word, unsigned int shift)
 	return (word >> shift) | (word << (32 - shift));
 }
 
+/**
+ * rol16 - rotate a 16-bit value left
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline __u16 rol16(__u16 word, unsigned int shift)

I don't think we can take that via wireless, and I think architectures should be able to override this if they can optimise it (though the compiler might be good enough...)

johannes

#2 lore raw
Quoted 7 lines · Johannes Berg
Quoted 7 lines
 include/linux/bitops.h |   40 ++++++++++++++++++++++++++++++++++++++++

+++ b/include/linux/bitops.h

include/linux/bitops.h +0 -0
@@ -65,6 +65,46 @@ static inline __u32 ror32(__u32 word, unsigned int shift)
 	return (word >> shift) | (word << (32 - shift));
 }
 
Quoted 10 lines

include/linux/bitops.h static inline __u32 ror32(__u32 word, unsigned int shift) · line 73

Quoted 6 lines
include/linux/bitops.h +6 -0
+/**
+ * rol16 - rotate a 16-bit value left
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline __u16 rol16(__u16 word, unsigned int shift)

I don't think we can take that via wireless, and I think architectures should be able to override this if they can optimise it (though the compiler might be good enough...)

OK, I'll get the common parts through Andrew and once that's in I'll resubmit the wireless parts.

Harvey