From: Sebastian Siewior <[EMAIL PROTECTED]>

There are three AES softwore modules in the kernel: One C version
and two arch specific assembly versions. The key expansion routine as
well as the the four lookup tables which are used during encryption
and/or decryption are the same.
This patch simply creates an independent module which shares the
data structures across the modules.

Signed-off-by: Sebastian Siewior <[EMAIL PROTECTED]>
---
 crypto/Kconfig       |    3 +
 crypto/Makefile      |    1 +
 crypto/aes_common.c  |  277 ++++++++++++++++++++++++++++++++++++++++++++++++++
 include/crypto/aes.h |   17 +++
 4 files changed, 298 insertions(+), 0 deletions(-)
 create mode 100644 crypto/aes_common.c

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 1f32071..26130d0 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -325,6 +325,9 @@ config CRYPTO_AES
 
          See <http://csrc.nist.gov/CryptoToolkit/aes/> for more information.
 
+config CRYPTO_AES_COMMON
+       tristate
+
 config CRYPTO_AES_586
        tristate "AES cipher algorithms (i586)"
        depends on (X86 || UML_X86) && !64BIT
diff --git a/crypto/Makefile b/crypto/Makefile
index 1f87db2..59b6a7e 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -41,6 +41,7 @@ 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_generic.o
+obj-$(CONFIG_CRYPTO_AES_COMMON) += aes_common.o
 obj-$(CONFIG_CRYPTO_CAMELLIA) += camellia.o
 obj-$(CONFIG_CRYPTO_CAST5) += cast5.o
 obj-$(CONFIG_CRYPTO_CAST6) += cast6.o
diff --git a/crypto/aes_common.c b/crypto/aes_common.c
new file mode 100644
index 0000000..6ba60cf
--- /dev/null
+++ b/crypto/aes_common.c
@@ -0,0 +1,277 @@
+/*
+ * Cryptographic API.
+ *
+ * AES Cipher Algorithm.
+ *
+ * Based on Brian Gladman's code.
+ *
+ * Linux developers:
+ *  Alexander Kjeldaas <[EMAIL PROTECTED]>
+ *  Herbert Valerio Riedel <[EMAIL PROTECTED]>
+ *  Kyle McMartin <[EMAIL PROTECTED]>
+ *  Adam J. Richter <[EMAIL PROTECTED]> (conversion to 2.5 API).
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * ---------------------------------------------------------------------------
+ * Copyright (c) 2002, Dr Brian Gladman <[EMAIL PROTECTED]>, Worcester, UK.
+ * All rights reserved.
+ *
+ * LICENSE TERMS
+ *
+ * The free distribution and use of this software in both source and binary
+ * form is allowed (with or without changes) provided that:
+ *
+ *   1. distributions of this source code include the above copyright
+ *      notice, this list of conditions and the following disclaimer;
+ *
+ *   2. distributions in binary form include the above copyright
+ *      notice, this list of conditions and the following disclaimer
+ *      in the documentation and/or other associated materials;
+ *
+ *   3. the copyright holder's name is not used to endorse products
+ *      built using this software without specific written permission.
+ *
+ * ALTERNATIVELY, provided that this notice is retained in full, this product
+ * may be distributed under the terms of the GNU General Public License (GPL),
+ * in which case the provisions of the GPL apply INSTEAD OF those given above.
+ *
+ * DISCLAIMER
+ *
+ * This software is provided 'as is' with no explicit or implied warranties
+ * in respect of its properties, including, but not limited to, correctness
+ * and/or fitness for purpose.
+ * ---------------------------------------------------------------------------
+ */
+
+#include <crypto/aes.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/crypto.h>
+#include <asm/byteorder.h>
+
+static inline u8 byte(const u32 x, const unsigned n)
+{
+       return x >> (n << 3);
+}
+
+static u8 pow_tab[256] __initdata;
+static u8 log_tab[256] __initdata;
+static u8 sbx_tab[256] __initdata;
+static u8 isb_tab[256] __initdata;
+
+static u32 rco_tab[10];
+u32 crypto_ft_tab[4][256];
+u32 crypto_it_tab[4][256];
+u32 crypto_fl_tab[4][256];
+u32 crypto_il_tab[4][256];
+
+EXPORT_SYMBOL_GPL(crypto_ft_tab);
+EXPORT_SYMBOL_GPL(crypto_it_tab);
+EXPORT_SYMBOL_GPL(crypto_fl_tab);
+EXPORT_SYMBOL_GPL(crypto_il_tab);
+
+static inline u8 __init f_mult (u8 a, u8 b)
+{
+       u8 aa = log_tab[a], cc = aa + log_tab[b];
+
+       return pow_tab[cc + (cc < aa ? 1 : 0)];
+}
+
+#define ff_mult(a,b)    (a && b ? f_mult(a, b) : 0)
+
+#define ls_box(x)                              \
+    ( crypto_fl_tab[0][byte(x, 0)] ^           \
+      crypto_fl_tab[1][byte(x, 1)] ^           \
+      crypto_fl_tab[2][byte(x, 2)] ^           \
+      crypto_fl_tab[3][byte(x, 3)] )
+
+static int __init gen_tabs (void)
+{
+       u32 i, t;
+       u8 p, q;
+
+       /* log and power tables for GF(2**8) finite field with
+          0x011b as modular polynomial - the simplest primitive
+          root is 0x03, used here to generate the tables */
+
+       for (i = 0, p = 1; i < 256; ++i) {
+               pow_tab[i] = (u8) p;
+               log_tab[p] = (u8) i;
+
+               p ^= (p << 1) ^ (p & 0x80 ? 0x01b : 0);
+       }
+
+       log_tab[1] = 0;
+
+       for (i = 0, p = 1; i < 10; ++i) {
+               rco_tab[i] = p;
+
+               p = (p << 1) ^ (p & 0x80 ? 0x01b : 0);
+       }
+
+       for (i = 0; i < 256; ++i) {
+               p = (i ? pow_tab[255 - log_tab[i]] : 0);
+               q = ((p >> 7) | (p << 1)) ^ ((p >> 6) | (p << 2));
+               p ^= 0x63 ^ q ^ ((q >> 6) | (q << 2));
+               sbx_tab[i] = p;
+               isb_tab[p] = (u8) i;
+       }
+
+       for (i = 0; i < 256; ++i) {
+               p = sbx_tab[i];
+
+               t = p;
+               crypto_fl_tab[0][i] = t;
+               crypto_fl_tab[1][i] = rol32(t, 8);
+               crypto_fl_tab[2][i] = rol32(t, 16);
+               crypto_fl_tab[3][i] = rol32(t, 24);
+
+               t = ((u32) ff_mult (2, p)) |
+                   ((u32) p << 8) |
+                   ((u32) p << 16) | ((u32) ff_mult (3, p) << 24);
+
+               crypto_ft_tab[0][i] = t;
+               crypto_ft_tab[1][i] = rol32(t, 8);
+               crypto_ft_tab[2][i] = rol32(t, 16);
+               crypto_ft_tab[3][i] = rol32(t, 24);
+
+               p = isb_tab[i];
+
+               t = p;
+               crypto_il_tab[0][i] = t;
+               crypto_il_tab[1][i] = rol32(t, 8);
+               crypto_il_tab[2][i] = rol32(t, 16);
+               crypto_il_tab[3][i] = rol32(t, 24);
+
+               t = ((u32) ff_mult (14, p)) |
+                   ((u32) ff_mult (9, p) << 8) |
+                   ((u32) ff_mult (13, p) << 16) |
+                   ((u32) ff_mult (11, p) << 24);
+
+               crypto_it_tab[0][i] = t;
+               crypto_it_tab[1][i] = rol32(t, 8);
+               crypto_it_tab[2][i] = rol32(t, 16);
+               crypto_it_tab[3][i] = rol32(t, 24);
+       }
+
+       return 0;
+}
+
+#define star_x(x) (((x) & 0x7f7f7f7f) << 1) ^ ((((x) & 0x80808080) >> 7) * 
0x1b)
+
+#define imix_col(y,x)       \
+    u   = star_x(x);        \
+    v   = star_x(u);        \
+    w   = star_x(v);        \
+    t   = w ^ (x);          \
+   (y)  = u ^ v ^ w;        \
+   (y) ^= ror32(u ^ t,  8) ^ \
+          ror32(v ^ t, 16) ^ \
+          ror32(t,24)
+
+/* initialise the key schedule from the user supplied key */
+
+#define loop4(i)                                    \
+{   t = ror32(t,  8); t = ls_box(t) ^ rco_tab[i];    \
+    t ^= ctx->key_enc[4 * i];     ctx->key_enc[4 * i + 4] = t;    \
+    t ^= ctx->key_enc[4 * i + 1]; ctx->key_enc[4 * i + 5] = t;    \
+    t ^= ctx->key_enc[4 * i + 2]; ctx->key_enc[4 * i + 6] = t;    \
+    t ^= ctx->key_enc[4 * i + 3]; ctx->key_enc[4 * i + 7] = t;    \
+}
+
+#define loop6(i)                                    \
+{   t = ror32(t,  8); t = ls_box(t) ^ rco_tab[i];    \
+    t ^= ctx->key_enc[6 * i];     ctx->key_enc[6 * i + 6] = t;    \
+    t ^= ctx->key_enc[6 * i + 1]; ctx->key_enc[6 * i + 7] = t;    \
+    t ^= ctx->key_enc[6 * i + 2]; ctx->key_enc[6 * i + 8] = t;    \
+    t ^= ctx->key_enc[6 * i + 3]; ctx->key_enc[6 * i + 9] = t;    \
+    t ^= ctx->key_enc[6 * i + 4]; ctx->key_enc[6 * i + 10] = t;   \
+    t ^= ctx->key_enc[6 * i + 5]; ctx->key_enc[6 * i + 11] = t;   \
+}
+
+#define loop8(i)                                    \
+{   t = ror32(t,  8); ; t = ls_box(t) ^ rco_tab[i];  \
+    t ^= ctx->key_enc[8 * i];     ctx->key_enc[8 * i + 8] = t;    \
+    t ^= ctx->key_enc[8 * i + 1]; ctx->key_enc[8 * i + 9] = t;    \
+    t ^= ctx->key_enc[8 * i + 2]; ctx->key_enc[8 * i + 10] = t;   \
+    t ^= ctx->key_enc[8 * i + 3]; ctx->key_enc[8 * i + 11] = t;   \
+    t  = ctx->key_enc[8 * i + 4] ^ ls_box(t);    \
+    ctx->key_enc[8 * i + 12] = t;                \
+    t ^= ctx->key_enc[8 * i + 5]; ctx->key_enc[8 * i + 13] = t;   \
+    t ^= ctx->key_enc[8 * i + 6]; ctx->key_enc[8 * i + 14] = t;   \
+    t ^= ctx->key_enc[8 * i + 7]; ctx->key_enc[8 * i + 15] = t;   \
+}
+
+int crypto_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
+               unsigned int key_len)
+{
+       struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
+       const __le32 *key = (const __le32 *)in_key;
+       u32 *flags = &tfm->crt_flags;
+       u32 i, j, t, u, v, w;
+
+       if (key_len % 8) {
+               *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
+               return -EINVAL;
+       }
+
+       ctx->key_length = key_len;
+
+       ctx->key_dec[key_len + 24] = ctx->key_enc[0] = le32_to_cpu(key[0]);
+       ctx->key_dec[key_len + 25] = ctx->key_enc[1] = le32_to_cpu(key[1]);
+       ctx->key_dec[key_len + 26] = ctx->key_enc[2] = le32_to_cpu(key[2]);
+       ctx->key_dec[key_len + 27] = ctx->key_enc[3] = le32_to_cpu(key[3]);
+
+       switch (key_len) {
+               case 16:
+                       t = ctx->key_enc[3];
+                       for (i = 0; i < 10; ++i)
+                               loop4(i);
+                       break;
+
+               case 24:
+                       ctx->key_enc[4] = le32_to_cpu(key[4]);
+                       t = ctx->key_enc[5] = le32_to_cpu(key[5]);
+                       for (i = 0; i < 8; ++i)
+                               loop6 (i);
+                       break;
+
+               case 32:
+                       ctx->key_enc[4] = le32_to_cpu(key[4]);
+                       ctx->key_enc[5] = le32_to_cpu(key[5]);
+                       ctx->key_enc[6] = le32_to_cpu(key[6]);
+                       t = ctx->key_enc[7] = le32_to_cpu(key[7]);
+                       for (i = 0; i < 7; ++i)
+                               loop8(i);
+                       break;
+       }
+
+       ctx->key_dec[0] = ctx->key_enc[key_len + 24];
+       ctx->key_dec[1] = ctx->key_enc[key_len + 25];
+       ctx->key_dec[2] = ctx->key_enc[key_len + 26];
+       ctx->key_dec[3] = ctx->key_enc[key_len + 27];
+
+       for (i = 4; i < key_len + 24; ++i) {
+               j = key_len + 24 - (i & ~3) + (i & 3);
+               imix_col(ctx->key_dec[j], ctx->key_enc[i]);
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(crypto_aes_set_key);
+
+static void damn_I_can_t_name_it_void(void)
+{
+}
+
+module_init(gen_tabs);
+module_exit(damn_I_can_t_name_it_void);
+
+MODULE_DESCRIPTION("Commom used functions for the Rijndael (AES) Cipher 
Algorithm");
+MODULE_LICENSE("Dual BSD/GPL");
diff --git a/include/crypto/aes.h b/include/crypto/aes.h
index 9ff842f..ab7c7c8 100644
--- a/include/crypto/aes.h
+++ b/include/crypto/aes.h
@@ -5,6 +5,9 @@
 #ifndef _CRYPTO_AES_H
 #define _CRYPTO_AES_H
 
+#include <linux/types.h>
+#include <linux/crypto.h>
+
 #define AES_MIN_KEY_SIZE       16
 #define AES_MAX_KEY_SIZE       32
 #define AES_KEYSIZE_128                16
@@ -12,4 +15,18 @@
 #define AES_KEYSIZE_256                32
 #define AES_BLOCK_SIZE         16
 
+struct crypto_aes_ctx {
+       u32 key_length;
+       u32 key_enc[60];
+       u32 key_dec[60];
+};
+
+extern u32 crypto_ft_tab[4][256];
+extern u32 crypto_it_tab[4][256];
+extern u32 crypto_fl_tab[4][256];
+extern u32 crypto_il_tab[4][256];
+
+int crypto_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
+               unsigned int key_len);
+
 #endif
-- 
1.5.3.4

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