+++ /dev/null
-/*
- * 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);
-}
-
-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];
-
-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(struct crypto_tfm *tfm, const u8 *in_key,
- unsigned int key_len)
-{
- struct 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;
-
- if (key_len % 8) {
- *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
- return -EINVAL;
- }
-
- 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]);
-
- 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]);
- }
-
- 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(struct crypto_tfm *tfm, u8 *out, const u8 *in)
-{
- const struct 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;
-
- 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];
-
- 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);
-
- dst[0] = cpu_to_le32(b0[0]);
- dst[1] = cpu_to_le32(b0[1]);
- dst[2] = cpu_to_le32(b0[2]);
- dst[3] = cpu_to_le32(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(struct crypto_tfm *tfm, u8 *out, const u8 *in)
-{
- const struct 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;
-
- 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];
-
- 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);
-
- dst[0] = cpu_to_le32(b0[0]);
- dst[1] = cpu_to_le32(b0[1]);
- dst[2] = cpu_to_le32(b0[2]);
- dst[3] = cpu_to_le32(b0[3]);
-}
-
-
-static struct crypto_alg aes_alg = {
- .cra_name = "aes",
- .cra_driver_name = "aes-generic",
- .cra_priority = 100,
- .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
- .cra_blocksize = AES_BLOCK_SIZE,
- .cra_ctxsize = sizeof(struct aes_ctx),
- .cra_alignmask = 3,
- .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");
-
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff