aboutsummaryrefslogtreecommitdiff
path: root/arch/i386/crypto/aes.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/i386/crypto/aes.c')
-rw-r--r--arch/i386/crypto/aes.c520
1 files changed, 520 insertions, 0 deletions
diff --git a/arch/i386/crypto/aes.c b/arch/i386/crypto/aes.c
new file mode 100644
index 000000000000..1019430fc1f1
--- /dev/null
+++ b/arch/i386/crypto/aes.c
@@ -0,0 +1,520 @@
+/*
+ *
+ * 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 <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(const u8 *src, u8 *dst, void *ctx);
+asmlinkage void aes_dec_blk(const u8 *src, u8 *dst, void *ctx);
+
+#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 u32_in(x) le32_to_cpu(*(const u32 *)(x))
+#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 ls_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);
+
+ /*
+ * table for key schedule if fl_tab above is
+ * not of the required form
+ */
+ ls_tab[0][i] = w;
+ ls_tab[1][i] = upr(w, 1);
+ ls_tab[2][i] = upr(w, 2);
+ ls_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(void *ctx_arg, const u8 *in_key, unsigned int key_len, u32 *flags)
+{
+ int i;
+ u32 ss[8];
+ struct aes_ctx *ctx = ctx_arg;
+
+ /* encryption schedule */
+
+ ctx->ekey[0] = ss[0] = u32_in(in_key);
+ ctx->ekey[1] = ss[1] = u32_in(in_key + 4);
+ ctx->ekey[2] = ss[2] = u32_in(in_key + 8);
+ ctx->ekey[3] = ss[3] = u32_in(in_key + 12);
+
+ 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] = u32_in(in_key + 16);
+ ctx->ekey[5] = ss[5] = u32_in(in_key + 20);
+ 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] = u32_in(in_key + 16);
+ ctx->ekey[5] = ss[5] = u32_in(in_key + 20);
+ ctx->ekey[6] = ss[6] = u32_in(in_key + 24);
+ ctx->ekey[7] = ss[7] = u32_in(in_key + 28);
+ 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] = u32_in(in_key);
+ ctx->dkey[1] = ss[1] = u32_in(in_key + 4);
+ ctx->dkey[2] = ss[2] = u32_in(in_key + 8);
+ ctx->dkey[3] = ss[3] = u32_in(in_key + 12);
+
+ 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] = u32_in(in_key + 16));
+ ctx->dkey[5] = ff(ss[5] = u32_in(in_key + 20));
+ 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] = u32_in(in_key + 16));
+ ctx->dkey[5] = ff(ss[5] = u32_in(in_key + 20));
+ ctx->dkey[6] = ff(ss[6] = u32_in(in_key + 24));
+ ctx->dkey[7] = ff(ss[7] = u32_in(in_key + 28));
+ kdf8(ctx->dkey, 0);
+ for (i = 1; i < 6; i++)
+ kd8(ctx->dkey, i);
+ kdl8(ctx->dkey, 6);
+ break;
+ }
+ return 0;
+}
+
+static inline void aes_encrypt(void *ctx, u8 *dst, const u8 *src)
+{
+ aes_enc_blk(src, dst, ctx);
+}
+static inline void aes_decrypt(void *ctx, u8 *dst, const u8 *src)
+{
+ aes_dec_blk(src, dst, ctx);
+}
+
+
+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
+ }
+ }
+};
+
+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");