Skip to content

Commit

Permalink
[CRYPTO] padlock-aes: Use generic setkey function
Browse files Browse the repository at this point in the history 
The Padlock AES setkey routine is the same as exported by the generic
implementation. So we could use it.

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Cc: Michal Ludvig <michal@logix.cz>
Tested-by: Stefan Hellermann <stefan@the2masters.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
  • Loading branch information
Sebastian Siewior authored and Herbert Xu committed Apr 21, 2008
1 parent 5427663 commit 7dc748e
Show file tree
Hide file tree
Showing 2 changed files with 20 additions and 301 deletions.
1 change: 1 addition & 0 deletions drivers/crypto/Kconfig
View file
Original file line number Diff line number Diff line change
Expand Up @@ -27,6 +27,7 @@ config CRYPTO_DEV_PADLOCK_AES
tristate "PadLock driver for AES algorithm"
depends on CRYPTO_DEV_PADLOCK
select CRYPTO_BLKCIPHER
select CRYPTO_AES
help
Use VIA PadLock for AES algorithm.

Expand Down
320 changes: 19 additions & 301 deletions drivers/crypto/padlock-aes.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -5,42 +5,6 @@
*
* Copyright (c) 2004 Michal Ludvig <michal@logix.cz>
*
* Key expansion routine taken from crypto/aes_generic.c
*
* 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.
* ---------------------------------------------------------------------------
*/

#include <crypto/algapi.h>
Expand All @@ -54,9 +18,6 @@
#include <asm/byteorder.h>
#include "padlock.h"

#define AES_EXTENDED_KEY_SIZE 64 /* in uint32_t units */
#define AES_EXTENDED_KEY_SIZE_B (AES_EXTENDED_KEY_SIZE * sizeof(uint32_t))

/* Control word. */
struct cword {
unsigned int __attribute__ ((__packed__))
Expand All @@ -70,218 +31,23 @@ struct cword {

/* Whenever making any changes to the following
* structure *make sure* you keep E, d_data
* and cword aligned on 16 Bytes boundaries!!! */
* and cword aligned on 16 Bytes boundaries and
* the Hardware can access 16 * 16 bytes of E and d_data
* (only the first 15 * 16 bytes matter but the HW reads
* more).
*/
struct aes_ctx {
u32 E[AES_MAX_KEYLENGTH_U32]
__attribute__ ((__aligned__(PADLOCK_ALIGNMENT)));
u32 d_data[AES_MAX_KEYLENGTH_U32]
__attribute__ ((__aligned__(PADLOCK_ALIGNMENT)));
struct {
struct cword encrypt;
struct cword decrypt;
} cword;
u32 *D;
int key_length;
u32 E[AES_EXTENDED_KEY_SIZE]
__attribute__ ((__aligned__(PADLOCK_ALIGNMENT)));
u32 d_data[AES_EXTENDED_KEY_SIZE]
__attribute__ ((__aligned__(PADLOCK_ALIGNMENT)));
};

/* ====== Key management routines ====== */

static inline uint32_t
generic_rotr32 (const uint32_t x, const unsigned bits)
{
const unsigned n = bits % 32;
return (x >> n) | (x << (32 - n));
}

static inline uint32_t
generic_rotl32 (const uint32_t x, const unsigned bits)
{
const unsigned n = bits % 32;
return (x << n) | (x >> (32 - n));
}

#define rotl generic_rotl32
#define rotr generic_rotr32

/*
* #define byte(x, nr) ((unsigned char)((x) >> (nr*8)))
*/
static inline uint8_t
byte(const uint32_t x, const unsigned n)
{
return x >> (n << 3);
}

#define E_KEY ctx->E
#define D_KEY ctx->D

static uint8_t pow_tab[256];
static uint8_t log_tab[256];
static uint8_t sbx_tab[256];
static uint8_t isb_tab[256];
static uint32_t rco_tab[10];
static uint32_t ft_tab[4][256];
static uint32_t it_tab[4][256];

static uint32_t fl_tab[4][256];
static uint32_t il_tab[4][256];

static inline uint8_t
f_mult (uint8_t a, uint8_t b)
{
uint8_t 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
gen_tabs (void)
{
uint32_t i, t;
uint8_t p, q;

/* log and power tables for GF(2**8) finite field with
0x011b as modular polynomial - the simplest prmitive
root is 0x03, used here to generate the tables */

for (i = 0, p = 1; i < 256; ++i) {
pow_tab[i] = (uint8_t) p;
log_tab[p] = (uint8_t) 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] = (uint8_t) i;
}

for (i = 0; i < 256; ++i) {
p = sbx_tab[i];

t = p;
fl_tab[0][i] = t;
fl_tab[1][i] = rotl (t, 8);
fl_tab[2][i] = rotl (t, 16);
fl_tab[3][i] = rotl (t, 24);

t = ((uint32_t) ff_mult (2, p)) |
((uint32_t) p << 8) |
((uint32_t) p << 16) | ((uint32_t) ff_mult (3, p) << 24);

ft_tab[0][i] = t;
ft_tab[1][i] = rotl (t, 8);
ft_tab[2][i] = rotl (t, 16);
ft_tab[3][i] = rotl (t, 24);

p = isb_tab[i];

t = p;
il_tab[0][i] = t;
il_tab[1][i] = rotl (t, 8);
il_tab[2][i] = rotl (t, 16);
il_tab[3][i] = rotl (t, 24);

t = ((uint32_t) ff_mult (14, p)) |
((uint32_t) ff_mult (9, p) << 8) |
((uint32_t) ff_mult (13, p) << 16) |
((uint32_t) ff_mult (11, p) << 24);

it_tab[0][i] = t;
it_tab[1][i] = rotl (t, 8);
it_tab[2][i] = rotl (t, 16);
it_tab[3][i] = rotl (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) ^= rotr(u ^ t, 8) ^ \
rotr(v ^ t, 16) ^ \
rotr(t,24)

/* initialise the key schedule from the user supplied key */

#define loop4(i) \
{ t = rotr(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 = rotr(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 = rotr(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; \
}

/* Tells whether the ACE is capable to generate
the extended key for a given key_len. */
static inline int
Expand Down Expand Up @@ -321,28 +87,24 @@ static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
struct aes_ctx *ctx = aes_ctx(tfm);
const __le32 *key = (const __le32 *)in_key;
u32 *flags = &tfm->crt_flags;
uint32_t i, t, u, v, w;
uint32_t P[AES_EXTENDED_KEY_SIZE];
uint32_t rounds;
struct crypto_aes_ctx gen_aes;

if (key_len % 8) {
*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
return -EINVAL;
}

ctx->key_length = key_len;

/*
* If the hardware is capable of generating the extended key
* itself we must supply the plain key for both encryption
* and decryption.
*/
ctx->D = ctx->E;

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->E[0] = le32_to_cpu(key[0]);
ctx->E[1] = le32_to_cpu(key[1]);
ctx->E[2] = le32_to_cpu(key[2]);
ctx->E[3] = le32_to_cpu(key[3]);

/* Prepare control words. */
memset(&ctx->cword, 0, sizeof(ctx->cword));
Expand All @@ -361,56 +123,13 @@ static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
ctx->cword.encrypt.keygen = 1;
ctx->cword.decrypt.keygen = 1;

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[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]);
}

/* PadLock needs a different format of the decryption key. */
rounds = 10 + (key_len - 16) / 4;

for (i = 0; i < rounds; i++) {
P[((i + 1) * 4) + 0] = D_KEY[((rounds - i - 1) * 4) + 0];
P[((i + 1) * 4) + 1] = D_KEY[((rounds - i - 1) * 4) + 1];
P[((i + 1) * 4) + 2] = D_KEY[((rounds - i - 1) * 4) + 2];
P[((i + 1) * 4) + 3] = D_KEY[((rounds - i - 1) * 4) + 3];
if (crypto_aes_expand_key(&gen_aes, in_key, key_len)) {
*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
return -EINVAL;
}

P[0] = E_KEY[(rounds * 4) + 0];
P[1] = E_KEY[(rounds * 4) + 1];
P[2] = E_KEY[(rounds * 4) + 2];
P[3] = E_KEY[(rounds * 4) + 3];

memcpy(D_KEY, P, AES_EXTENDED_KEY_SIZE_B);

memcpy(ctx->E, gen_aes.key_enc, AES_MAX_KEYLENGTH);
memcpy(ctx->D, gen_aes.key_dec, AES_MAX_KEYLENGTH);
return 0;
}

Expand Down Expand Up @@ -675,7 +394,6 @@ static int __init padlock_init(void)
return -ENODEV;
}

gen_tabs();
if ((ret = crypto_register_alg(&aes_alg)))
goto aes_err;

Expand Down

0 comments on commit 7dc748e

Please sign in to comment.