From: Sebastian Siewior <sebastian@xxxxxxxxxxxxx> 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 <sebastian@xxxxxxxxxxxxx> --- 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 <astor@xxxxxxx> + * Herbert Valerio Riedel <hvr@xxxxxxxxxx> + * Kyle McMartin <kyle@xxxxxxxxxx> + * Adam J. Richter <adam@xxxxxxxxxxxxx> (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 <brg@xxxxxxxxxxxxx>, 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 - To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
