/* * Cryptographic API. * * AES Cipher Algorithm. * * Based on Brian Gladman's code. * * Linux developers: *  Alexander Kjeldaas <astor@fast.no> *  Herbert Valerio Riedel <hvr@hvrlab.org> *  Kyle McMartin <kyle@debian.org> *  Adam J. Richter <adam@yggdrasil.com> (conversion to 2.5 API). *  Andreas Steinmetz <ast@domdv.de> (adapted to x86_64 assembler) * * 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@gladman.me.uk>, 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. * --------------------------------------------------------------------------- *//* Some changes from the Gladman version:    s/RIJNDAEL(e_key)/E_KEY/g    s/RIJNDAEL(d_key)/D_KEY/g*/#include <asm/byteorder.h>#include <linux/bitops.h>#include <linux/crypto.h>#include <linux/errno.h>#include <linux/init.h>#include <linux/module.h>#include <linux/types.h>#define AES_MIN_KEY_SIZE	16#define AES_MAX_KEY_SIZE	32#define AES_BLOCK_SIZE		16/* * #define byte(x, nr) ((unsigned char)((x) >> (nr*8))) */static inline u8 byte(const u32 x, const unsigned n){	return x >> (n << 3);}struct aes_ctx{	u32 key_length;	u32 buf[120];};#define E_KEY (&ctx->buf[0])#define D_KEY (&ctx->buf[60])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 aes_ft_tab[4][256];u32 aes_it_tab[4][256];u32 aes_fl_tab[4][256];u32 aes_il_tab[4][256];static inline u8 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)				\	(aes_fl_tab[0][byte(x, 0)] ^		\	 aes_fl_tab[1][byte(x, 1)] ^		\	 aes_fl_tab[2][byte(x, 2)] ^		\	 aes_fl_tab[3][byte(x, 3)])static void __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;		aes_fl_tab[0][i] = t;		aes_fl_tab[1][i] = rol32(t, 8);		aes_fl_tab[2][i] = rol32(t, 16);		aes_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);		aes_ft_tab[0][i] = t;		aes_ft_tab[1][i] = rol32(t, 8);		aes_ft_tab[2][i] = rol32(t, 16);		aes_ft_tab[3][i] = rol32(t, 24);		p = isb_tab[i];		t = p;		aes_il_tab[0][i] = t;		aes_il_tab[1][i] = rol32(t, 8);		aes_il_tab[2][i] = rol32(t, 16);		aes_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);		aes_it_tab[0][i] = t;		aes_it_tab[1][i] = rol32(t, 8);		aes_it_tab[2][i] = rol32(t, 16);		aes_it_tab[3][i] = rol32(t, 24);	}}#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 ^= E_KEY[4 * i];     E_KEY[4 * i + 4] = t;	\	t ^= E_KEY[4 * i + 1]; E_KEY[4 * i + 5] = t;	\	t ^= E_KEY[4 * i + 2]; E_KEY[4 * i + 6] = t;	\	t ^= E_KEY[4 * i + 3]; E_KEY[4 * i + 7] = t;	\}#define loop6(i)					\{							\	t = ror32(t,  8); t = ls_box(t) ^ rco_tab[i];	\	t ^= E_KEY[6 * i];     E_KEY[6 * i + 6] = t;	\	t ^= E_KEY[6 * i + 1]; E_KEY[6 * i + 7] = t;	\	t ^= E_KEY[6 * i + 2]; E_KEY[6 * i + 8] = t;	\	t ^= E_KEY[6 * i + 3]; E_KEY[6 * i + 9] = t;	\	t ^= E_KEY[6 * i + 4]; E_KEY[6 * i + 10] = t;	\	t ^= E_KEY[6 * i + 5]; E_KEY[6 * i + 11] = t;	\}#define loop8(i)					\{							\	t = ror32(t,  8); ; t = ls_box(t) ^ rco_tab[i];	\	t ^= E_KEY[8 * i];     E_KEY[8 * i + 8] = t;	\	t ^= E_KEY[8 * i + 1]; E_KEY[8 * i + 9] = t;	\	t ^= E_KEY[8 * i + 2]; E_KEY[8 * i + 10] = t;	\	t ^= E_KEY[8 * i + 3]; E_KEY[8 * i + 11] = t;	\	t  = E_KEY[8 * i + 4] ^ ls_box(t);		\	E_KEY[8 * i + 12] = t;				\	t ^= E_KEY[8 * i + 5]; E_KEY[8 * i + 13] = t;	\	t ^= E_KEY[8 * i + 6]; E_KEY[8 * i + 14] = t;	\	t ^= E_KEY[8 * i + 7]; E_KEY[8 * i + 15] = t;	\}static int aes_set_key(void *ctx_arg, const u8 *in_key, unsigned int key_len,		       u32 *flags){	struct aes_ctx *ctx = ctx_arg;	const __le32 *key = (const __le32 *)in_key;	u32 i, j, t, u, v, w;	if (key_len != 16 && key_len != 24 && key_len != 32) {		*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;		return -EINVAL;	}	ctx->key_length = key_len;	D_KEY[key_len + 24] = E_KEY[0] = le32_to_cpu(key[0]);	D_KEY[key_len + 25] = E_KEY[1] = le32_to_cpu(key[1]);	D_KEY[key_len + 26] = E_KEY[2] = le32_to_cpu(key[2]);	D_KEY[key_len + 27] = E_KEY[3] = le32_to_cpu(key[3]);	switch (key_len) {	case 16:		t = E_KEY[3];		for (i = 0; i < 10; ++i)			loop4(i);		break;	case 24:		E_KEY[4] = le32_to_cpu(key[4]);		t = E_KEY[5] = le32_to_cpu(key[5]);		for (i = 0; i < 8; ++i)			loop6 (i);		break;	case 32:		E_KEY[4] = le32_to_cpu(key[4]);		E_KEY[5] = le32_to_cpu(key[5]);		E_KEY[6] = le32_to_cpu(key[6]);		t = E_KEY[7] = le32_to_cpu(key[7]);		for (i = 0; i < 7; ++i)			loop8(i);		break;	}	D_KEY[0] = E_KEY[key_len + 24];	D_KEY[1] = E_KEY[key_len + 25];	D_KEY[2] = E_KEY[key_len + 26];	D_KEY[3] = E_KEY[key_len + 27];	for (i = 4; i < key_len + 24; ++i) {		j = key_len + 24 - (i & ~3) + (i & 3);		imix_col(D_KEY[j], E_KEY[i]);	}	return 0;}extern void aes_encrypt(void *ctx_arg, u8 *out, const u8 *in);extern void aes_decrypt(void *ctx_arg, u8 *out, const u8 *in);static struct crypto_alg aes_alg = {	.cra_name		=	"aes",	.cra_driver_name	=	"aes-x86_64",	.cra_priority		=	200,	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,	.cra_blocksize		=	AES_BLOCK_SIZE,	.cra_ctxsize		=	sizeof(struct aes_ctx),	.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,			.cia_encrypt	 	=	aes_encrypt,			.cia_decrypt	  	=	aes_decrypt		}	}};static int __init aes_init(void){	gen_tabs();	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");MODULE_LICENSE("GPL");MODULE_ALIAS("aes");