1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
468 lines
13 KiB
C
468 lines
13 KiB
C
/*
|
|
* Cryptographic API.
|
|
*
|
|
* Support for VIA PadLock hardware crypto engine.
|
|
*
|
|
* Copyright (c) 2004 Michal Ludvig <michal@logix.cz>
|
|
*
|
|
* Key expansion routine taken from crypto/aes.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 <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/types.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/crypto.h>
|
|
#include <linux/interrupt.h>
|
|
#include <asm/byteorder.h>
|
|
#include "padlock.h"
|
|
|
|
#define AES_MIN_KEY_SIZE 16 /* in uint8_t units */
|
|
#define AES_MAX_KEY_SIZE 32 /* ditto */
|
|
#define AES_BLOCK_SIZE 16 /* ditto */
|
|
#define AES_EXTENDED_KEY_SIZE 64 /* in uint32_t units */
|
|
#define AES_EXTENDED_KEY_SIZE_B (AES_EXTENDED_KEY_SIZE * sizeof(uint32_t))
|
|
|
|
struct aes_ctx {
|
|
uint32_t e_data[AES_EXTENDED_KEY_SIZE+4];
|
|
uint32_t d_data[AES_EXTENDED_KEY_SIZE+4];
|
|
uint32_t *E;
|
|
uint32_t *D;
|
|
int key_length;
|
|
};
|
|
|
|
/* ====== 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 uint32_t_in(x) le32_to_cpu(*(const uint32_t *)(x))
|
|
#define uint32_t_out(to, from) (*(uint32_t *)(to) = cpu_to_le32(from))
|
|
|
|
#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
|
|
aes_hw_extkey_available(uint8_t key_len)
|
|
{
|
|
/* TODO: We should check the actual CPU model/stepping
|
|
as it's possible that the capability will be
|
|
added in the next CPU revisions. */
|
|
if (key_len == 16)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
aes_set_key(void *ctx_arg, const uint8_t *in_key, unsigned int key_len, uint32_t *flags)
|
|
{
|
|
struct aes_ctx *ctx = ctx_arg;
|
|
uint32_t i, t, u, v, w;
|
|
uint32_t P[AES_EXTENDED_KEY_SIZE];
|
|
uint32_t rounds;
|
|
|
|
if (key_len != 16 && key_len != 24 && key_len != 32) {
|
|
*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
|
|
return -EINVAL;
|
|
}
|
|
|
|
ctx->key_length = key_len;
|
|
|
|
ctx->E = ctx->e_data;
|
|
ctx->D = ctx->d_data;
|
|
|
|
/* Ensure 16-Bytes alignmentation of keys for VIA PadLock. */
|
|
if ((int)(ctx->e_data) & 0x0F)
|
|
ctx->E += 4 - (((int)(ctx->e_data) & 0x0F) / sizeof (ctx->e_data[0]));
|
|
|
|
if ((int)(ctx->d_data) & 0x0F)
|
|
ctx->D += 4 - (((int)(ctx->d_data) & 0x0F) / sizeof (ctx->d_data[0]));
|
|
|
|
E_KEY[0] = uint32_t_in (in_key);
|
|
E_KEY[1] = uint32_t_in (in_key + 4);
|
|
E_KEY[2] = uint32_t_in (in_key + 8);
|
|
E_KEY[3] = uint32_t_in (in_key + 12);
|
|
|
|
/* Don't generate extended keys if the hardware can do it. */
|
|
if (aes_hw_extkey_available(key_len))
|
|
return 0;
|
|
|
|
switch (key_len) {
|
|
case 16:
|
|
t = E_KEY[3];
|
|
for (i = 0; i < 10; ++i)
|
|
loop4 (i);
|
|
break;
|
|
|
|
case 24:
|
|
E_KEY[4] = uint32_t_in (in_key + 16);
|
|
t = E_KEY[5] = uint32_t_in (in_key + 20);
|
|
for (i = 0; i < 8; ++i)
|
|
loop6 (i);
|
|
break;
|
|
|
|
case 32:
|
|
E_KEY[4] = uint32_t_in (in_key + 16);
|
|
E_KEY[5] = uint32_t_in (in_key + 20);
|
|
E_KEY[6] = uint32_t_in (in_key + 24);
|
|
t = E_KEY[7] = uint32_t_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]);
|
|
}
|
|
|
|
/* 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];
|
|
}
|
|
|
|
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);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* ====== Encryption/decryption routines ====== */
|
|
|
|
/* This is the real call to PadLock. */
|
|
static inline void
|
|
padlock_xcrypt_ecb(uint8_t *input, uint8_t *output, uint8_t *key,
|
|
void *control_word, uint32_t count)
|
|
{
|
|
asm volatile ("pushfl; popfl"); /* enforce key reload. */
|
|
asm volatile (".byte 0xf3,0x0f,0xa7,0xc8" /* rep xcryptecb */
|
|
: "+S"(input), "+D"(output)
|
|
: "d"(control_word), "b"(key), "c"(count));
|
|
}
|
|
|
|
static void
|
|
aes_padlock(void *ctx_arg, uint8_t *out_arg, const uint8_t *in_arg, int encdec)
|
|
{
|
|
/* Don't blindly modify this structure - the items must
|
|
fit on 16-Bytes boundaries! */
|
|
struct padlock_xcrypt_data {
|
|
uint8_t buf[AES_BLOCK_SIZE];
|
|
union cword cword;
|
|
};
|
|
|
|
struct aes_ctx *ctx = ctx_arg;
|
|
char bigbuf[sizeof(struct padlock_xcrypt_data) + 16];
|
|
struct padlock_xcrypt_data *data;
|
|
void *key;
|
|
|
|
/* Place 'data' at the first 16-Bytes aligned address in 'bigbuf'. */
|
|
if (((long)bigbuf) & 0x0F)
|
|
data = (void*)(bigbuf + 16 - ((long)bigbuf & 0x0F));
|
|
else
|
|
data = (void*)bigbuf;
|
|
|
|
/* Prepare Control word. */
|
|
memset (data, 0, sizeof(struct padlock_xcrypt_data));
|
|
data->cword.b.encdec = !encdec; /* in the rest of cryptoapi ENC=1/DEC=0 */
|
|
data->cword.b.rounds = 10 + (ctx->key_length - 16) / 4;
|
|
data->cword.b.ksize = (ctx->key_length - 16) / 8;
|
|
|
|
/* Is the hardware capable to generate the extended key? */
|
|
if (!aes_hw_extkey_available(ctx->key_length))
|
|
data->cword.b.keygen = 1;
|
|
|
|
/* ctx->E starts with a plain key - if the hardware is capable
|
|
to generate the extended key itself we must supply
|
|
the plain key for both Encryption and Decryption. */
|
|
if (encdec == CRYPTO_DIR_ENCRYPT || data->cword.b.keygen == 0)
|
|
key = ctx->E;
|
|
else
|
|
key = ctx->D;
|
|
|
|
memcpy(data->buf, in_arg, AES_BLOCK_SIZE);
|
|
padlock_xcrypt_ecb(data->buf, data->buf, key, &data->cword, 1);
|
|
memcpy(out_arg, data->buf, AES_BLOCK_SIZE);
|
|
}
|
|
|
|
static void
|
|
aes_encrypt(void *ctx_arg, uint8_t *out, const uint8_t *in)
|
|
{
|
|
aes_padlock(ctx_arg, out, in, CRYPTO_DIR_ENCRYPT);
|
|
}
|
|
|
|
static void
|
|
aes_decrypt(void *ctx_arg, uint8_t *out, const uint8_t *in)
|
|
{
|
|
aes_padlock(ctx_arg, out, in, CRYPTO_DIR_DECRYPT);
|
|
}
|
|
|
|
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
|
|
}
|
|
}
|
|
};
|
|
|
|
int __init padlock_init_aes(void)
|
|
{
|
|
printk(KERN_NOTICE PFX "Using VIA PadLock ACE for AES algorithm.\n");
|
|
|
|
gen_tabs();
|
|
return crypto_register_alg(&aes_alg);
|
|
}
|
|
|
|
void __exit padlock_fini_aes(void)
|
|
{
|
|
crypto_unregister_alg(&aes_alg);
|
|
}
|