[CRYPTO]: Add i586 optimized AES

Below is an updated version of patch from Fruhwirth which integrates the 
Gladman AES code into the crypto API.

I've tried to ensure that this is done as simply as possible: the user 
gets the asm version by default if it's suitable.

I've also now added the alternate GPL licensing provided by Brian Gladman, 
and licensed the code as GPL.
Signed-off-by: James Morris <jmorris@redhat.com>
Signed-off-by: David S. Miller <davem@redhat.com>

Documentation/crypto/api-intro.txt

@@ -215,6 +215,7 @@ AES algorithm contributors:
   Herbert Valerio Riedel
   Kyle McMartin
   Adam J. Richter
+  Fruhwirth Clemens (i586)
 
 CAST5 algorithm contributors:
   Kartikey Mahendra Bhatt (original developers unknown, FSF copyright).

arch/i386/Makefile

@@ -104,7 +104,8 @@ head-y := arch/i386/kernel/head.o arch/i386/kernel/init_task.o
 libs-y 					+= arch/i386/lib/
 core-y					+= arch/i386/kernel/ \
 					   arch/i386/mm/ \
-					   arch/i386/$(mcore-y)/
+					   arch/i386/$(mcore-y)/ \
+					   arch/i386/crypto/
 drivers-$(CONFIG_MATH_EMULATION)	+= arch/i386/math-emu/
 drivers-$(CONFIG_PCI)			+= arch/i386/pci/
 # must be linked after kernel/

arch/i386/crypto/Makefile

+# 
+# i386/crypto/Makefile 
+# 
+# Arch-specific CryptoAPI modules.
+# 
+
+obj-$(CONFIG_CRYPTO_AES_586) += aes-i586.o
+
+aes-i586-y := aes-i586-asm.o aes-i586-glue.o

arch/i386/crypto/aes-i586-glue.c

+/* 
+ * 
+ * Glue Code for optimized 586 assembler version of AES
+ *
+ * Copyright (c) 2001, Dr Brian Gladman <brg@gladman.uk.net>, Worcester, UK.
+ * Copyright (c) 2003, Adam J. Richter <adam@yggdrasil.com> (conversion to
+ * 2.5 API).
+ * Copyright (c) 2003, 2004 Fruhwirth Clemens <clemens@endorphin.org>
+*/
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/crypto.h>
+#include <linux/linkage.h>
+
+#define AES_MIN_KEY_SIZE	16
+#define AES_MAX_KEY_SIZE	32
+#define AES_BLOCK_SIZE		16
+#define AES_KS_LENGTH   4 * AES_BLOCK_SIZE
+#define AES_RC_LENGTH   (9 * AES_BLOCK_SIZE) / 8 - 8
+
+typedef struct
+{
+    u_int32_t	 aes_Nkey;	// the number of words in the key input block
+    u_int32_t	 aes_Nrnd;	// the number of cipher rounds
+    u_int32_t	 aes_e_key[AES_KS_LENGTH];   // the encryption key schedule
+    u_int32_t	 aes_d_key[AES_KS_LENGTH];   // the decryption key schedule
+    u_int32_t	 aes_Ncol;	// the number of columns in the cipher state
+} aes_context;
+
+/*
+ * The Cipher Interface
+ */
+ 
+asmlinkage void aes_set_key(void *, const unsigned char [], const int, const int);
+
+
+
+/* Actually:
+ * extern void aes_encrypt(const aes_context *, unsigned char [], const unsigned char []);
+ * extern void aes_decrypt(const aes_context *, unsigned char [], const unsigned char []);
+*/
+ 
+asmlinkage void aes_encrypt(void*, unsigned char [], const unsigned char []);
+asmlinkage void aes_decrypt(void*, unsigned char [], const unsigned char []);
+
+static int aes_set_key_glue(void *cx, const u8 *key,unsigned int key_length, u32 *flags)
+{
+	if(key_length != 16 && key_length != 24 && key_length != 32)
+	{
+ 		*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
+		return -EINVAL;
+	}
+	aes_set_key(cx, key,key_length,0);
+	return 0;
+}
+
+#ifdef CONFIG_REGPARM
+static void aes_encrypt_glue(void* a, unsigned char b[], const unsigned char c[]) {
+	aes_encrypt(a,b,c);
+}
+static void aes_decrypt_glue(void* a, unsigned char b[], const unsigned char c[]) {
+	aes_decrypt(a,b,c);
+}
+#else
+#define aes_encrypt_glue aes_encrypt
+#define aes_decrypt_glue aes_decrypt
+#endif /* CONFIG_REGPARM */
+
+static struct crypto_alg aes_alg = {
+	.cra_name		=	"aes",
+	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
+	.cra_blocksize		=	AES_BLOCK_SIZE,
+	.cra_ctxsize		=	sizeof(aes_context),
+	.cra_module		=	THIS_MODULE,
+	.cra_list		=	LIST_HEAD_INIT(aes_alg.cra_list),
+	.cra_u			=	{
+		.cipher = {
+			.cia_min_keysize	=	AES_MIN_KEY_SIZE,
+			.cia_max_keysize	=	AES_MAX_KEY_SIZE,
+			.cia_setkey	   	= 	aes_set_key_glue,
+			.cia_encrypt	 	=	aes_encrypt_glue,
+			.cia_decrypt	  	=	aes_decrypt_glue
+		}
+	}
+};
+
+static int __init aes_init(void)
+{
+	return crypto_register_alg(&aes_alg);
+}
+
+static void __exit aes_fini(void)
+{
+	crypto_unregister_alg(&aes_alg);
+}
+
+module_init(aes_init);
+module_exit(aes_fini);
+
+MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm, i586 asm optimized");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Fruhwirth Clemens");
+MODULE_ALIAS("aes");

crypto/Kconfig

@@ -118,9 +118,9 @@ config CRYPTO_SERPENT
 	  See also:
 	  http://www.cl.cam.ac.uk/~rja14/serpent.html
 
-config CRYPTO_AES
+config CRYPTO_AES_GENERIC
 	tristate "AES cipher algorithms"
-	depends on CRYPTO
+	depends on CRYPTO && !(X86 && !X86_64)
 	help
 	  AES cipher algorithms (FIPS-197). AES uses the Rijndael 
 	  algorithm.
@@ -138,6 +138,26 @@ config CRYPTO_AES
 
 	  See http://csrc.nist.gov/CryptoToolkit/aes/ for more information.
 
+config CRYPTO_AES_586
+	tristate "AES cipher algorithms (i586)"
+	depends on CRYPTO && (X86 && !X86_64)
+	help
+	  AES cipher algorithms (FIPS-197). AES uses the Rijndael 
+	  algorithm.
+
+	  Rijndael appears to be consistently a very good performer in
+	  both hardware and software across a wide range of computing 
+	  environments regardless of its use in feedback or non-feedback 
+	  modes. Its key setup time is excellent, and its key agility is 
+	  good. Rijndael's very low memory requirements make it very well 
+	  suited for restricted-space environments, in which it also 
+	  demonstrates excellent performance. Rijndael's operations are 
+	  among the easiest to defend against power and timing attacks.	
+
+	  The AES specifies three key sizes: 128, 192 and 256 bits	  
+
+	  See http://csrc.nist.gov/encryption/aes/ for more information.
+
 config CRYPTO_CAST5
 	tristate "CAST5 (CAST-128) cipher algorithm"
 	depends on CRYPTO