[CRYPTO] aes-generic: Make key generation exportable

This patch exports four tables and the set_key() routine. This ressources
can be shared by other AES implementations (aes-x86_64 for instance).
The decryption key has been turned around (deckey[0] is the first piece
of the key instead of deckey[keylen+20]). The encrypt/decrypt functions
are looking now identical (except they are using different tables and
key).

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Sebastian Siewior 2007-11-08 21:20:30 +08:00 committed by Herbert Xu
parent be5fb27012
commit 96e82e4551
2 changed files with 136 additions and 129 deletions

View File

@ -47,11 +47,6 @@
* ---------------------------------------------------------------------------
*/
/* Some changes from the Gladman version:
s/RIJNDAEL(e_key)/E_KEY/g
s/RIJNDAEL(d_key)/D_KEY/g
*/
#include <crypto/aes.h>
#include <linux/module.h>
#include <linux/init.h>
@ -60,32 +55,26 @@
#include <linux/crypto.h>
#include <asm/byteorder.h>
/*
* #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 {
int 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];
static u32 ft_tab[4][256];
static u32 it_tab[4][256];
static u32 fl_tab[4][256];
static u32 il_tab[4][256];
u32 crypto_ft_tab[4][256];
u32 crypto_fl_tab[4][256];
u32 crypto_it_tab[4][256];
u32 crypto_il_tab[4][256];
EXPORT_SYMBOL_GPL(crypto_ft_tab);
EXPORT_SYMBOL_GPL(crypto_fl_tab);
EXPORT_SYMBOL_GPL(crypto_it_tab);
EXPORT_SYMBOL_GPL(crypto_il_tab);
static inline u8 __init f_mult(u8 a, u8 b)
{
@ -134,37 +123,37 @@ static void __init gen_tabs(void)
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);
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);
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);
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;
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);
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);
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);
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);
}
}
@ -184,69 +173,69 @@ static void __init gen_tabs(void)
} while (0)
#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)]
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)]
#define loop4(i) do { \
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; \
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; \
} while (0)
#define loop6(i) do { \
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; \
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; \
} while (0)
#define loop8(i) do { \
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; \
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; \
} while (0)
static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
int crypto_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
unsigned int key_len)
{
struct aes_ctx *ctx = crypto_tfm_ctx(tfm);
struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
const __le32 *key = (const __le32 *)in_key;
u32 *flags = &tfm->crt_flags;
u32 i, t, u, v, w;
u32 i, t, u, v, w, j;
if (key_len % 8) {
*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
@ -255,54 +244,55 @@ static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
ctx->key_length = key_len;
E_KEY[0] = le32_to_cpu(key[0]);
E_KEY[1] = le32_to_cpu(key[1]);
E_KEY[2] = le32_to_cpu(key[2]);
E_KEY[3] = le32_to_cpu(key[3]);
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 = E_KEY[3];
t = ctx->key_enc[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]);
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:
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]);
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;
}
D_KEY[0] = E_KEY[0];
D_KEY[1] = E_KEY[1];
D_KEY[2] = E_KEY[2];
D_KEY[3] = E_KEY[3];
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) {
imix_col(D_KEY[i], E_KEY[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);
/* encrypt a block of text */
#define f_rn(bo, bi, n, k) do { \
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); \
bo[n] = crypto_ft_tab[0][byte(bi[n], 0)] ^ \
crypto_ft_tab[1][byte(bi[(n + 1) & 3], 1)] ^ \
crypto_ft_tab[2][byte(bi[(n + 2) & 3], 2)] ^ \
crypto_ft_tab[3][byte(bi[(n + 3) & 3], 3)] ^ *(k + n); \
} while (0)
#define f_nround(bo, bi, k) do {\
@ -314,10 +304,10 @@ static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
} while (0)
#define f_rl(bo, bi, n, k) do { \
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); \
bo[n] = crypto_fl_tab[0][byte(bi[n], 0)] ^ \
crypto_fl_tab[1][byte(bi[(n + 1) & 3], 1)] ^ \
crypto_fl_tab[2][byte(bi[(n + 2) & 3], 2)] ^ \
crypto_fl_tab[3][byte(bi[(n + 3) & 3], 3)] ^ *(k + n); \
} while (0)
#define f_lround(bo, bi, k) do {\
@ -329,23 +319,24 @@ static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
static void aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
const struct aes_ctx *ctx = crypto_tfm_ctx(tfm);
const struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
const __le32 *src = (const __le32 *)in;
__le32 *dst = (__le32 *)out;
u32 b0[4], b1[4];
const u32 *kp = E_KEY + 4;
const u32 *kp = ctx->key_enc + 4;
const int key_len = ctx->key_length;
b0[0] = le32_to_cpu(src[0]) ^ E_KEY[0];
b0[1] = le32_to_cpu(src[1]) ^ E_KEY[1];
b0[2] = le32_to_cpu(src[2]) ^ E_KEY[2];
b0[3] = le32_to_cpu(src[3]) ^ E_KEY[3];
b0[0] = le32_to_cpu(src[0]) ^ ctx->key_enc[0];
b0[1] = le32_to_cpu(src[1]) ^ ctx->key_enc[1];
b0[2] = le32_to_cpu(src[2]) ^ ctx->key_enc[2];
b0[3] = le32_to_cpu(src[3]) ^ ctx->key_enc[3];
if (ctx->key_length > 24) {
if (key_len > 24) {
f_nround(b1, b0, kp);
f_nround(b0, b1, kp);
}
if (ctx->key_length > 16) {
if (key_len > 16) {
f_nround(b1, b0, kp);
f_nround(b0, b1, kp);
}
@ -370,10 +361,10 @@ static void aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
/* decrypt a block of text */
#define i_rn(bo, bi, n, k) do { \
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); \
bo[n] = crypto_it_tab[0][byte(bi[n], 0)] ^ \
crypto_it_tab[1][byte(bi[(n + 3) & 3], 1)] ^ \
crypto_it_tab[2][byte(bi[(n + 2) & 3], 2)] ^ \
crypto_it_tab[3][byte(bi[(n + 1) & 3], 3)] ^ *(k + n); \
} while (0)
#define i_nround(bo, bi, k) do {\
@ -381,14 +372,14 @@ static void aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
i_rn(bo, bi, 1, k); \
i_rn(bo, bi, 2, k); \
i_rn(bo, bi, 3, k); \
k -= 4; \
k += 4; \
} while (0)
#define i_rl(bo, bi, n, k) do { \
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); \
bo[n] = crypto_il_tab[0][byte(bi[n], 0)] ^ \
crypto_il_tab[1][byte(bi[(n + 3) & 3], 1)] ^ \
crypto_il_tab[2][byte(bi[(n + 2) & 3], 2)] ^ \
crypto_il_tab[3][byte(bi[(n + 1) & 3], 3)] ^ *(k + n); \
} while (0)
#define i_lround(bo, bi, k) do {\
@ -400,17 +391,17 @@ static void aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
static void aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
const struct aes_ctx *ctx = crypto_tfm_ctx(tfm);
const struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
const __le32 *src = (const __le32 *)in;
__le32 *dst = (__le32 *)out;
u32 b0[4], b1[4];
const int key_len = ctx->key_length;
const u32 *kp = D_KEY + key_len + 20;
const u32 *kp = ctx->key_dec + 4;
b0[0] = le32_to_cpu(src[0]) ^ E_KEY[key_len + 24];
b0[1] = le32_to_cpu(src[1]) ^ E_KEY[key_len + 25];
b0[2] = le32_to_cpu(src[2]) ^ E_KEY[key_len + 26];
b0[3] = le32_to_cpu(src[3]) ^ E_KEY[key_len + 27];
b0[0] = le32_to_cpu(src[0]) ^ ctx->key_dec[0];
b0[1] = le32_to_cpu(src[1]) ^ ctx->key_dec[1];
b0[2] = le32_to_cpu(src[2]) ^ ctx->key_dec[2];
b0[3] = le32_to_cpu(src[3]) ^ ctx->key_dec[3];
if (key_len > 24) {
i_nround(b1, b0, kp);
@ -445,7 +436,7 @@ static struct crypto_alg aes_alg = {
.cra_priority = 100,
.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct aes_ctx),
.cra_ctxsize = sizeof(struct crypto_aes_ctx),
.cra_alignmask = 3,
.cra_module = THIS_MODULE,
.cra_list = LIST_HEAD_INIT(aes_alg.cra_list),
@ -453,7 +444,7 @@ static struct crypto_alg aes_alg = {
.cipher = {
.cia_min_keysize = AES_MIN_KEY_SIZE,
.cia_max_keysize = AES_MAX_KEY_SIZE,
.cia_setkey = aes_set_key,
.cia_setkey = crypto_aes_set_key,
.cia_encrypt = aes_encrypt,
.cia_decrypt = aes_decrypt
}

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@ -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 +15,17 @@
#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_fl_tab[4][256];
extern u32 crypto_it_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