alistair23-linux/crypto/aes.c
Jesper Juhl 77933d7276 [PATCH] clean up inline static vs static inline
`gcc -W' likes to complain if the static keyword is not at the beginning of
the declaration.  This patch fixes all remaining occurrences of "inline
static" up with "static inline" in the entire kernel tree (140 occurrences in
47 files).

While making this change I came across a few lines with trailing whitespace
that I also fixed up, I have also added or removed a blank line or two here
and there, but there are no functional changes in the patch.

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:20 -07:00

452 lines
11 KiB
C

/*
* 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).
*
* 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 <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/crypto.h>
#include <asm/byteorder.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);
}
#define u32_in(x) le32_to_cpu(*(const u32 *)(x))
#define u32_out(to, from) (*(u32 *)(to) = cpu_to_le32(from))
struct aes_ctx {
int key_length;
u32 E[60];
u32 D[60];
};
#define E_KEY ctx->E
#define D_KEY ctx->D
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];
static u32 ft_tab[4][256];
static u32 it_tab[4][256];
static u32 fl_tab[4][256];
static u32 il_tab[4][256];
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 f_rn(bo, bi, n, k) \
bo[n] = ft_tab[0][byte(bi[n],0)] ^ \
ft_tab[1][byte(bi[(n + 1) & 3],1)] ^ \
ft_tab[2][byte(bi[(n + 2) & 3],2)] ^ \
ft_tab[3][byte(bi[(n + 3) & 3],3)] ^ *(k + n)
#define i_rn(bo, bi, n, k) \
bo[n] = it_tab[0][byte(bi[n],0)] ^ \
it_tab[1][byte(bi[(n + 3) & 3],1)] ^ \
it_tab[2][byte(bi[(n + 2) & 3],2)] ^ \
it_tab[3][byte(bi[(n + 1) & 3],3)] ^ *(k + n)
#define ls_box(x) \
( fl_tab[0][byte(x, 0)] ^ \
fl_tab[1][byte(x, 1)] ^ \
fl_tab[2][byte(x, 2)] ^ \
fl_tab[3][byte(x, 3)] )
#define f_rl(bo, bi, n, k) \
bo[n] = fl_tab[0][byte(bi[n],0)] ^ \
fl_tab[1][byte(bi[(n + 1) & 3],1)] ^ \
fl_tab[2][byte(bi[(n + 2) & 3],2)] ^ \
fl_tab[3][byte(bi[(n + 3) & 3],3)] ^ *(k + n)
#define i_rl(bo, bi, n, k) \
bo[n] = il_tab[0][byte(bi[n],0)] ^ \
il_tab[1][byte(bi[(n + 3) & 3],1)] ^ \
il_tab[2][byte(bi[(n + 2) & 3],2)] ^ \
il_tab[3][byte(bi[(n + 1) & 3],3)] ^ *(k + n)
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;
fl_tab[0][i] = t;
fl_tab[1][i] = rol32(t, 8);
fl_tab[2][i] = rol32(t, 16);
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);
ft_tab[0][i] = t;
ft_tab[1][i] = rol32(t, 8);
ft_tab[2][i] = rol32(t, 16);
ft_tab[3][i] = rol32(t, 24);
p = isb_tab[i];
t = p;
il_tab[0][i] = t;
il_tab[1][i] = rol32(t, 8);
il_tab[2][i] = rol32(t, 16);
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);
it_tab[0][i] = t;
it_tab[1][i] = rol32(t, 8);
it_tab[2][i] = rol32(t, 16);
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;
u32 i, 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;
E_KEY[0] = u32_in (in_key);
E_KEY[1] = u32_in (in_key + 4);
E_KEY[2] = u32_in (in_key + 8);
E_KEY[3] = u32_in (in_key + 12);
switch (key_len) {
case 16:
t = E_KEY[3];
for (i = 0; i < 10; ++i)
loop4 (i);
break;
case 24:
E_KEY[4] = u32_in (in_key + 16);
t = E_KEY[5] = u32_in (in_key + 20);
for (i = 0; i < 8; ++i)
loop6 (i);
break;
case 32:
E_KEY[4] = u32_in (in_key + 16);
E_KEY[5] = u32_in (in_key + 20);
E_KEY[6] = u32_in (in_key + 24);
t = E_KEY[7] = u32_in (in_key + 28);
for (i = 0; i < 7; ++i)
loop8 (i);
break;
}
D_KEY[0] = E_KEY[0];
D_KEY[1] = E_KEY[1];
D_KEY[2] = E_KEY[2];
D_KEY[3] = E_KEY[3];
for (i = 4; i < key_len + 24; ++i) {
imix_col (D_KEY[i], E_KEY[i]);
}
return 0;
}
/* encrypt a block of text */
#define f_nround(bo, bi, k) \
f_rn(bo, bi, 0, k); \
f_rn(bo, bi, 1, k); \
f_rn(bo, bi, 2, k); \
f_rn(bo, bi, 3, k); \
k += 4
#define f_lround(bo, bi, k) \
f_rl(bo, bi, 0, k); \
f_rl(bo, bi, 1, k); \
f_rl(bo, bi, 2, k); \
f_rl(bo, bi, 3, k)
static void aes_encrypt(void *ctx_arg, u8 *out, const u8 *in)
{
const struct aes_ctx *ctx = ctx_arg;
u32 b0[4], b1[4];
const u32 *kp = E_KEY + 4;
b0[0] = u32_in (in) ^ E_KEY[0];
b0[1] = u32_in (in + 4) ^ E_KEY[1];
b0[2] = u32_in (in + 8) ^ E_KEY[2];
b0[3] = u32_in (in + 12) ^ E_KEY[3];
if (ctx->key_length > 24) {
f_nround (b1, b0, kp);
f_nround (b0, b1, kp);
}
if (ctx->key_length > 16) {
f_nround (b1, b0, kp);
f_nround (b0, b1, kp);
}
f_nround (b1, b0, kp);
f_nround (b0, b1, kp);
f_nround (b1, b0, kp);
f_nround (b0, b1, kp);
f_nround (b1, b0, kp);
f_nround (b0, b1, kp);
f_nround (b1, b0, kp);
f_nround (b0, b1, kp);
f_nround (b1, b0, kp);
f_lround (b0, b1, kp);
u32_out (out, b0[0]);
u32_out (out + 4, b0[1]);
u32_out (out + 8, b0[2]);
u32_out (out + 12, b0[3]);
}
/* decrypt a block of text */
#define i_nround(bo, bi, k) \
i_rn(bo, bi, 0, k); \
i_rn(bo, bi, 1, k); \
i_rn(bo, bi, 2, k); \
i_rn(bo, bi, 3, k); \
k -= 4
#define i_lround(bo, bi, k) \
i_rl(bo, bi, 0, k); \
i_rl(bo, bi, 1, k); \
i_rl(bo, bi, 2, k); \
i_rl(bo, bi, 3, k)
static void aes_decrypt(void *ctx_arg, u8 *out, const u8 *in)
{
const struct aes_ctx *ctx = ctx_arg;
u32 b0[4], b1[4];
const int key_len = ctx->key_length;
const u32 *kp = D_KEY + key_len + 20;
b0[0] = u32_in (in) ^ E_KEY[key_len + 24];
b0[1] = u32_in (in + 4) ^ E_KEY[key_len + 25];
b0[2] = u32_in (in + 8) ^ E_KEY[key_len + 26];
b0[3] = u32_in (in + 12) ^ E_KEY[key_len + 27];
if (key_len > 24) {
i_nround (b1, b0, kp);
i_nround (b0, b1, kp);
}
if (key_len > 16) {
i_nround (b1, b0, kp);
i_nround (b0, b1, kp);
}
i_nround (b1, b0, kp);
i_nround (b0, b1, kp);
i_nround (b1, b0, kp);
i_nround (b0, b1, kp);
i_nround (b1, b0, kp);
i_nround (b0, b1, kp);
i_nround (b1, b0, kp);
i_nround (b0, b1, kp);
i_nround (b1, b0, kp);
i_lround (b0, b1, kp);
u32_out (out, b0[0]);
u32_out (out + 4, b0[1]);
u32_out (out + 8, b0[2]);
u32_out (out + 12, b0[3]);
}
static struct crypto_alg aes_alg = {
.cra_name = "aes",
.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("Dual BSD/GPL");