[CRYPTO] twofish: Split out common c code

This patch splits up the twofish crypto routine into a common part ( key
setup  ) which will be uses by all twofish crypto modules ( generic-c , i586
assembler and x86_64 assembler ) and generic-c part. It also creates a new
header file which will be used by all 3 modules.

This eliminates all code duplication.

Correctness was verified with the tcrypt module and automated test scripts.

Signed-off-by: Joachim Fritschi <jfritschi@freenet.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/Kconfig

@@ -131,6 +131,7 @@ config CRYPTO_BLOWFISH
 config CRYPTO_TWOFISH
 	tristate "Twofish cipher algorithm"
 	depends on CRYPTO
+	select CRYPTO_TWOFISH_COMMON
 	help
 	  Twofish cipher algorithm.
 
@@ -142,6 +143,13 @@ config CRYPTO_TWOFISH
 	  See also:
 	  <http://www.schneier.com/twofish.html>
 
+config CRYPTO_TWOFISH_COMMON
+	tristate
+	depends on CRYPTO
+	help
+	  Common parts of the Twofish cipher algorithm shared by the
+	  generic c and the assembler implementations.
+
 config CRYPTO_SERPENT
 	tristate "Serpent cipher algorithm"
 	depends on CRYPTO

crypto/Makefile

@@ -19,6 +19,7 @@ obj-$(CONFIG_CRYPTO_TGR192) += tgr192.o
 obj-$(CONFIG_CRYPTO_DES) += des.o
 obj-$(CONFIG_CRYPTO_BLOWFISH) += blowfish.o
 obj-$(CONFIG_CRYPTO_TWOFISH) += twofish.o
+obj-$(CONFIG_CRYPTO_TWOFISH_COMMON) += twofish_common.o
 obj-$(CONFIG_CRYPTO_SERPENT) += serpent.o
 obj-$(CONFIG_CRYPTO_AES) += aes.o
 obj-$(CONFIG_CRYPTO_CAST5) += cast5.o