| /* |
| * |
| * Glue Code for optimized 586 assembler version of AES |
| * |
| * Copyright (c) 2002, Dr Brian Gladman <>, 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. |
| * |
| * Copyright (c) 2003, Adam J. Richter <adam@yggdrasil.com> (conversion to |
| * 2.5 API). |
| * Copyright (c) 2003, 2004 Fruhwirth Clemens <clemens@endorphin.org> |
| * Copyright (c) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com> |
| * |
| */ |
| |
| #include <asm/byteorder.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/types.h> |
| #include <linux/crypto.h> |
| #include <linux/linkage.h> |
| |
| asmlinkage void aes_enc_blk(struct crypto_tfm *tfm, u8 *dst, const u8 *src); |
| asmlinkage void aes_dec_blk(struct crypto_tfm *tfm, u8 *dst, const u8 *src); |
| |
| #define AES_MIN_KEY_SIZE 16 |
| #define AES_MAX_KEY_SIZE 32 |
| #define AES_BLOCK_SIZE 16 |
| #define AES_KS_LENGTH 4 * AES_BLOCK_SIZE |
| #define RC_LENGTH 29 |
| |
| struct aes_ctx { |
| u32 ekey[AES_KS_LENGTH]; |
| u32 rounds; |
| u32 dkey[AES_KS_LENGTH]; |
| }; |
| |
| #define WPOLY 0x011b |
| #define bytes2word(b0, b1, b2, b3) \ |
| (((u32)(b3) << 24) | ((u32)(b2) << 16) | ((u32)(b1) << 8) | (b0)) |
| |
| /* define the finite field multiplies required for Rijndael */ |
| #define f2(x) ((x) ? pow[log[x] + 0x19] : 0) |
| #define f3(x) ((x) ? pow[log[x] + 0x01] : 0) |
| #define f9(x) ((x) ? pow[log[x] + 0xc7] : 0) |
| #define fb(x) ((x) ? pow[log[x] + 0x68] : 0) |
| #define fd(x) ((x) ? pow[log[x] + 0xee] : 0) |
| #define fe(x) ((x) ? pow[log[x] + 0xdf] : 0) |
| #define fi(x) ((x) ? pow[255 - log[x]]: 0) |
| |
| static inline u32 upr(u32 x, int n) |
| { |
| return (x << 8 * n) | (x >> (32 - 8 * n)); |
| } |
| |
| static inline u8 bval(u32 x, int n) |
| { |
| return x >> 8 * n; |
| } |
| |
| /* The forward and inverse affine transformations used in the S-box */ |
| #define fwd_affine(x) \ |
| (w = (u32)x, w ^= (w<<1)^(w<<2)^(w<<3)^(w<<4), 0x63^(u8)(w^(w>>8))) |
| |
| #define inv_affine(x) \ |
| (w = (u32)x, w = (w<<1)^(w<<3)^(w<<6), 0x05^(u8)(w^(w>>8))) |
| |
| static u32 rcon_tab[RC_LENGTH]; |
| |
| u32 ft_tab[4][256]; |
| u32 fl_tab[4][256]; |
| static u32 im_tab[4][256]; |
| u32 il_tab[4][256]; |
| u32 it_tab[4][256]; |
| |
| static void gen_tabs(void) |
| { |
| u32 i, w; |
| u8 pow[512], log[256]; |
| |
| /* |
| * log and power tables for GF(2^8) finite field with |
| * WPOLY as modular polynomial - the simplest primitive |
| * root is 0x03, used here to generate the tables. |
| */ |
| i = 0; w = 1; |
| |
| do { |
| pow[i] = (u8)w; |
| pow[i + 255] = (u8)w; |
| log[w] = (u8)i++; |
| w ^= (w << 1) ^ (w & 0x80 ? WPOLY : 0); |
| } while (w != 1); |
| |
| for(i = 0, w = 1; i < RC_LENGTH; ++i) { |
| rcon_tab[i] = bytes2word(w, 0, 0, 0); |
| w = f2(w); |
| } |
| |
| for(i = 0; i < 256; ++i) { |
| u8 b; |
| |
| b = fwd_affine(fi((u8)i)); |
| w = bytes2word(f2(b), b, b, f3(b)); |
| |
| /* tables for a normal encryption round */ |
| ft_tab[0][i] = w; |
| ft_tab[1][i] = upr(w, 1); |
| ft_tab[2][i] = upr(w, 2); |
| ft_tab[3][i] = upr(w, 3); |
| w = bytes2word(b, 0, 0, 0); |
| |
| /* |
| * tables for last encryption round |
| * (may also be used in the key schedule) |
| */ |
| fl_tab[0][i] = w; |
| fl_tab[1][i] = upr(w, 1); |
| fl_tab[2][i] = upr(w, 2); |
| fl_tab[3][i] = upr(w, 3); |
| |
| b = fi(inv_affine((u8)i)); |
| w = bytes2word(fe(b), f9(b), fd(b), fb(b)); |
| |
| /* tables for the inverse mix column operation */ |
| im_tab[0][b] = w; |
| im_tab[1][b] = upr(w, 1); |
| im_tab[2][b] = upr(w, 2); |
| im_tab[3][b] = upr(w, 3); |
| |
| /* tables for a normal decryption round */ |
| it_tab[0][i] = w; |
| it_tab[1][i] = upr(w,1); |
| it_tab[2][i] = upr(w,2); |
| it_tab[3][i] = upr(w,3); |
| |
| w = bytes2word(b, 0, 0, 0); |
| |
| /* tables for last decryption round */ |
| il_tab[0][i] = w; |
| il_tab[1][i] = upr(w,1); |
| il_tab[2][i] = upr(w,2); |
| il_tab[3][i] = upr(w,3); |
| } |
| } |
| |
| #define four_tables(x,tab,vf,rf,c) \ |
| ( tab[0][bval(vf(x,0,c),rf(0,c))] ^ \ |
| tab[1][bval(vf(x,1,c),rf(1,c))] ^ \ |
| tab[2][bval(vf(x,2,c),rf(2,c))] ^ \ |
| tab[3][bval(vf(x,3,c),rf(3,c))] \ |
| ) |
| |
| #define vf1(x,r,c) (x) |
| #define rf1(r,c) (r) |
| #define rf2(r,c) ((r-c)&3) |
| |
| #define inv_mcol(x) four_tables(x,im_tab,vf1,rf1,0) |
| #define ls_box(x,c) four_tables(x,fl_tab,vf1,rf2,c) |
| |
| #define ff(x) inv_mcol(x) |
| |
| #define ke4(k,i) \ |
| { \ |
| k[4*(i)+4] = ss[0] ^= ls_box(ss[3],3) ^ rcon_tab[i]; \ |
| k[4*(i)+5] = ss[1] ^= ss[0]; \ |
| k[4*(i)+6] = ss[2] ^= ss[1]; \ |
| k[4*(i)+7] = ss[3] ^= ss[2]; \ |
| } |
| |
| #define kel4(k,i) \ |
| { \ |
| k[4*(i)+4] = ss[0] ^= ls_box(ss[3],3) ^ rcon_tab[i]; \ |
| k[4*(i)+5] = ss[1] ^= ss[0]; \ |
| k[4*(i)+6] = ss[2] ^= ss[1]; k[4*(i)+7] = ss[3] ^= ss[2]; \ |
| } |
| |
| #define ke6(k,i) \ |
| { \ |
| k[6*(i)+ 6] = ss[0] ^= ls_box(ss[5],3) ^ rcon_tab[i]; \ |
| k[6*(i)+ 7] = ss[1] ^= ss[0]; \ |
| k[6*(i)+ 8] = ss[2] ^= ss[1]; \ |
| k[6*(i)+ 9] = ss[3] ^= ss[2]; \ |
| k[6*(i)+10] = ss[4] ^= ss[3]; \ |
| k[6*(i)+11] = ss[5] ^= ss[4]; \ |
| } |
| |
| #define kel6(k,i) \ |
| { \ |
| k[6*(i)+ 6] = ss[0] ^= ls_box(ss[5],3) ^ rcon_tab[i]; \ |
| k[6*(i)+ 7] = ss[1] ^= ss[0]; \ |
| k[6*(i)+ 8] = ss[2] ^= ss[1]; \ |
| k[6*(i)+ 9] = ss[3] ^= ss[2]; \ |
| } |
| |
| #define ke8(k,i) \ |
| { \ |
| k[8*(i)+ 8] = ss[0] ^= ls_box(ss[7],3) ^ rcon_tab[i]; \ |
| k[8*(i)+ 9] = ss[1] ^= ss[0]; \ |
| k[8*(i)+10] = ss[2] ^= ss[1]; \ |
| k[8*(i)+11] = ss[3] ^= ss[2]; \ |
| k[8*(i)+12] = ss[4] ^= ls_box(ss[3],0); \ |
| k[8*(i)+13] = ss[5] ^= ss[4]; \ |
| k[8*(i)+14] = ss[6] ^= ss[5]; \ |
| k[8*(i)+15] = ss[7] ^= ss[6]; \ |
| } |
| |
| #define kel8(k,i) \ |
| { \ |
| k[8*(i)+ 8] = ss[0] ^= ls_box(ss[7],3) ^ rcon_tab[i]; \ |
| k[8*(i)+ 9] = ss[1] ^= ss[0]; \ |
| k[8*(i)+10] = ss[2] ^= ss[1]; \ |
| k[8*(i)+11] = ss[3] ^= ss[2]; \ |
| } |
| |
| #define kdf4(k,i) \ |
| { \ |
| ss[0] = ss[0] ^ ss[2] ^ ss[1] ^ ss[3]; \ |
| ss[1] = ss[1] ^ ss[3]; \ |
| ss[2] = ss[2] ^ ss[3]; \ |
| ss[3] = ss[3]; \ |
| ss[4] = ls_box(ss[(i+3) % 4], 3) ^ rcon_tab[i]; \ |
| ss[i % 4] ^= ss[4]; \ |
| ss[4] ^= k[4*(i)]; \ |
| k[4*(i)+4] = ff(ss[4]); \ |
| ss[4] ^= k[4*(i)+1]; \ |
| k[4*(i)+5] = ff(ss[4]); \ |
| ss[4] ^= k[4*(i)+2]; \ |
| k[4*(i)+6] = ff(ss[4]); \ |
| ss[4] ^= k[4*(i)+3]; \ |
| k[4*(i)+7] = ff(ss[4]); \ |
| } |
| |
| #define kd4(k,i) \ |
| { \ |
| ss[4] = ls_box(ss[(i+3) % 4], 3) ^ rcon_tab[i]; \ |
| ss[i % 4] ^= ss[4]; \ |
| ss[4] = ff(ss[4]); \ |
| k[4*(i)+4] = ss[4] ^= k[4*(i)]; \ |
| k[4*(i)+5] = ss[4] ^= k[4*(i)+1]; \ |
| k[4*(i)+6] = ss[4] ^= k[4*(i)+2]; \ |
| k[4*(i)+7] = ss[4] ^= k[4*(i)+3]; \ |
| } |
| |
| #define kdl4(k,i) \ |
| { \ |
| ss[4] = ls_box(ss[(i+3) % 4], 3) ^ rcon_tab[i]; \ |
| ss[i % 4] ^= ss[4]; \ |
| k[4*(i)+4] = (ss[0] ^= ss[1]) ^ ss[2] ^ ss[3]; \ |
| k[4*(i)+5] = ss[1] ^ ss[3]; \ |
| k[4*(i)+6] = ss[0]; \ |
| k[4*(i)+7] = ss[1]; \ |
| } |
| |
| #define kdf6(k,i) \ |
| { \ |
| ss[0] ^= ls_box(ss[5],3) ^ rcon_tab[i]; \ |
| k[6*(i)+ 6] = ff(ss[0]); \ |
| ss[1] ^= ss[0]; \ |
| k[6*(i)+ 7] = ff(ss[1]); \ |
| ss[2] ^= ss[1]; \ |
| k[6*(i)+ 8] = ff(ss[2]); \ |
| ss[3] ^= ss[2]; \ |
| k[6*(i)+ 9] = ff(ss[3]); \ |
| ss[4] ^= ss[3]; \ |
| k[6*(i)+10] = ff(ss[4]); \ |
| ss[5] ^= ss[4]; \ |
| k[6*(i)+11] = ff(ss[5]); \ |
| } |
| |
| #define kd6(k,i) \ |
| { \ |
| ss[6] = ls_box(ss[5],3) ^ rcon_tab[i]; \ |
| ss[0] ^= ss[6]; ss[6] = ff(ss[6]); \ |
| k[6*(i)+ 6] = ss[6] ^= k[6*(i)]; \ |
| ss[1] ^= ss[0]; \ |
| k[6*(i)+ 7] = ss[6] ^= k[6*(i)+ 1]; \ |
| ss[2] ^= ss[1]; \ |
| k[6*(i)+ 8] = ss[6] ^= k[6*(i)+ 2]; \ |
| ss[3] ^= ss[2]; \ |
| k[6*(i)+ 9] = ss[6] ^= k[6*(i)+ 3]; \ |
| ss[4] ^= ss[3]; \ |
| k[6*(i)+10] = ss[6] ^= k[6*(i)+ 4]; \ |
| ss[5] ^= ss[4]; \ |
| k[6*(i)+11] = ss[6] ^= k[6*(i)+ 5]; \ |
| } |
| |
| #define kdl6(k,i) \ |
| { \ |
| ss[0] ^= ls_box(ss[5],3) ^ rcon_tab[i]; \ |
| k[6*(i)+ 6] = ss[0]; \ |
| ss[1] ^= ss[0]; \ |
| k[6*(i)+ 7] = ss[1]; \ |
| ss[2] ^= ss[1]; \ |
| k[6*(i)+ 8] = ss[2]; \ |
| ss[3] ^= ss[2]; \ |
| k[6*(i)+ 9] = ss[3]; \ |
| } |
| |
| #define kdf8(k,i) \ |
| { \ |
| ss[0] ^= ls_box(ss[7],3) ^ rcon_tab[i]; \ |
| k[8*(i)+ 8] = ff(ss[0]); \ |
| ss[1] ^= ss[0]; \ |
| k[8*(i)+ 9] = ff(ss[1]); \ |
| ss[2] ^= ss[1]; \ |
| k[8*(i)+10] = ff(ss[2]); \ |
| ss[3] ^= ss[2]; \ |
| k[8*(i)+11] = ff(ss[3]); \ |
| ss[4] ^= ls_box(ss[3],0); \ |
| k[8*(i)+12] = ff(ss[4]); \ |
| ss[5] ^= ss[4]; \ |
| k[8*(i)+13] = ff(ss[5]); \ |
| ss[6] ^= ss[5]; \ |
| k[8*(i)+14] = ff(ss[6]); \ |
| ss[7] ^= ss[6]; \ |
| k[8*(i)+15] = ff(ss[7]); \ |
| } |
| |
| #define kd8(k,i) \ |
| { \ |
| u32 __g = ls_box(ss[7],3) ^ rcon_tab[i]; \ |
| ss[0] ^= __g; \ |
| __g = ff(__g); \ |
| k[8*(i)+ 8] = __g ^= k[8*(i)]; \ |
| ss[1] ^= ss[0]; \ |
| k[8*(i)+ 9] = __g ^= k[8*(i)+ 1]; \ |
| ss[2] ^= ss[1]; \ |
| k[8*(i)+10] = __g ^= k[8*(i)+ 2]; \ |
| ss[3] ^= ss[2]; \ |
| k[8*(i)+11] = __g ^= k[8*(i)+ 3]; \ |
| __g = ls_box(ss[3],0); \ |
| ss[4] ^= __g; \ |
| __g = ff(__g); \ |
| k[8*(i)+12] = __g ^= k[8*(i)+ 4]; \ |
| ss[5] ^= ss[4]; \ |
| k[8*(i)+13] = __g ^= k[8*(i)+ 5]; \ |
| ss[6] ^= ss[5]; \ |
| k[8*(i)+14] = __g ^= k[8*(i)+ 6]; \ |
| ss[7] ^= ss[6]; \ |
| k[8*(i)+15] = __g ^= k[8*(i)+ 7]; \ |
| } |
| |
| #define kdl8(k,i) \ |
| { \ |
| ss[0] ^= ls_box(ss[7],3) ^ rcon_tab[i]; \ |
| k[8*(i)+ 8] = ss[0]; \ |
| ss[1] ^= ss[0]; \ |
| k[8*(i)+ 9] = ss[1]; \ |
| ss[2] ^= ss[1]; \ |
| k[8*(i)+10] = ss[2]; \ |
| ss[3] ^= ss[2]; \ |
| k[8*(i)+11] = ss[3]; \ |
| } |
| |
| static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, |
| unsigned int key_len, u32 *flags) |
| { |
| int i; |
| u32 ss[8]; |
| struct aes_ctx *ctx = crypto_tfm_ctx(tfm); |
| const __le32 *key = (const __le32 *)in_key; |
| |
| /* encryption schedule */ |
| |
| ctx->ekey[0] = ss[0] = le32_to_cpu(key[0]); |
| ctx->ekey[1] = ss[1] = le32_to_cpu(key[1]); |
| ctx->ekey[2] = ss[2] = le32_to_cpu(key[2]); |
| ctx->ekey[3] = ss[3] = le32_to_cpu(key[3]); |
| |
| switch(key_len) { |
| case 16: |
| for (i = 0; i < 9; i++) |
| ke4(ctx->ekey, i); |
| kel4(ctx->ekey, 9); |
| ctx->rounds = 10; |
| break; |
| |
| case 24: |
| ctx->ekey[4] = ss[4] = le32_to_cpu(key[4]); |
| ctx->ekey[5] = ss[5] = le32_to_cpu(key[5]); |
| for (i = 0; i < 7; i++) |
| ke6(ctx->ekey, i); |
| kel6(ctx->ekey, 7); |
| ctx->rounds = 12; |
| break; |
| |
| case 32: |
| ctx->ekey[4] = ss[4] = le32_to_cpu(key[4]); |
| ctx->ekey[5] = ss[5] = le32_to_cpu(key[5]); |
| ctx->ekey[6] = ss[6] = le32_to_cpu(key[6]); |
| ctx->ekey[7] = ss[7] = le32_to_cpu(key[7]); |
| for (i = 0; i < 6; i++) |
| ke8(ctx->ekey, i); |
| kel8(ctx->ekey, 6); |
| ctx->rounds = 14; |
| break; |
| |
| default: |
| *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; |
| return -EINVAL; |
| } |
| |
| /* decryption schedule */ |
| |
| ctx->dkey[0] = ss[0] = le32_to_cpu(key[0]); |
| ctx->dkey[1] = ss[1] = le32_to_cpu(key[1]); |
| ctx->dkey[2] = ss[2] = le32_to_cpu(key[2]); |
| ctx->dkey[3] = ss[3] = le32_to_cpu(key[3]); |
| |
| switch (key_len) { |
| case 16: |
| kdf4(ctx->dkey, 0); |
| for (i = 1; i < 9; i++) |
| kd4(ctx->dkey, i); |
| kdl4(ctx->dkey, 9); |
| break; |
| |
| case 24: |
| ctx->dkey[4] = ff(ss[4] = le32_to_cpu(key[4])); |
| ctx->dkey[5] = ff(ss[5] = le32_to_cpu(key[5])); |
| kdf6(ctx->dkey, 0); |
| for (i = 1; i < 7; i++) |
| kd6(ctx->dkey, i); |
| kdl6(ctx->dkey, 7); |
| break; |
| |
| case 32: |
| ctx->dkey[4] = ff(ss[4] = le32_to_cpu(key[4])); |
| ctx->dkey[5] = ff(ss[5] = le32_to_cpu(key[5])); |
| ctx->dkey[6] = ff(ss[6] = le32_to_cpu(key[6])); |
| ctx->dkey[7] = ff(ss[7] = le32_to_cpu(key[7])); |
| kdf8(ctx->dkey, 0); |
| for (i = 1; i < 6; i++) |
| kd8(ctx->dkey, i); |
| kdl8(ctx->dkey, 6); |
| break; |
| } |
| return 0; |
| } |
| |
| static void aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) |
| { |
| aes_enc_blk(tfm, dst, src); |
| } |
| |
| static void aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) |
| { |
| aes_dec_blk(tfm, dst, src); |
| } |
| |
| static struct crypto_alg aes_alg = { |
| .cra_name = "aes", |
| .cra_driver_name = "aes-i586", |
| .cra_priority = 200, |
| .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, i586 asm optimized"); |
| MODULE_LICENSE("Dual BSD/GPL"); |
| MODULE_AUTHOR("Fruhwirth Clemens, James Morris, Brian Gladman, Adam Richter"); |
| MODULE_ALIAS("aes"); |