kern/lib/random/rijndael.c - upstream - Git at Google

 /*	$OpenBSD: rijndael.c,v 1.6 2000/12/09 18:51:34 markus Exp $ */

 /* contrib/pgcrypto/rijndael.c */

 /* This is an independent implementation of the encryption algorithm:	*/
 /*																		*/
 /*		   RIJNDAEL by Joan Daemen and Vincent Rijmen					*/
 /*																		*/
 /* which is a candidate algorithm in the Advanced Encryption Standard	*/
 /* programme of the US National Institute of Standards and Technology.	*/
 /*																		*/
 /* Copyright in this implementation is held by Dr B R Gladman but I		*/
 /* hereby give permission for its free direct or derivative use subject */
 /* to acknowledgment of its origin and compliance with any conditions	*/
 /* that the originators of the algorithm place on its exploitation.		*/
 /*																		*/
 /* Dr Brian Gladman (gladman@seven77.demon.co.uk) 14th January 1999		*/

 /* Timing data for Rijndael (rijndael.c)

 Algorithm: rijndael (rijndael.c)

 128 bit key:
 Key Setup:	  305/1389 cycles (encrypt/decrypt)
 Encrypt:	   374 cycles =    68.4 mbits/sec
 Decrypt:	   352 cycles =    72.7 mbits/sec
 Mean:		   363 cycles =    70.5 mbits/sec

 192 bit key:
 Key Setup:	  277/1595 cycles (encrypt/decrypt)
 Encrypt:	   439 cycles =    58.3 mbits/sec
 Decrypt:	   425 cycles =    60.2 mbits/sec
 Mean:		   432 cycles =    59.3 mbits/sec

 256 bit key:
 Key Setup:	  374/1960 cycles (encrypt/decrypt)
 Encrypt:	   502 cycles =    51.0 mbits/sec
 Decrypt:	   498 cycles =    51.4 mbits/sec
 Mean:		   500 cycles =    51.2 mbits/sec

 */

 #include <random/rijndael.h>

 #include "rijndael.tbl"

 /* 3. Basic macros for speeding up generic operations				*/

 /* Circular rotate of 32 bit values									*/

 #define rotr(x, n) (((x) >> ((int)(n))) | ((x) << (32 - (int)(n))))
 #define rotl(x, n) (((x) << ((int)(n))) | ((x) >> (32 - (int)(n))))

 /* Invert byte order in a 32 bit variable							*/

 #define bswap(x) ((rotl((x), 8) & 0x00ff00ff) | (rotr((x), 8) & 0xff00ff00))

 /* Extract byte from a 32 bit quantity (little endian notation)		*/

 #define byte(x, n) ((uint8_t)((x) >> (8 * (n))))

 #define io_swap(x) (x)

 #define ff_mult(a, b)                                                          \
 	((a) && (b) ? pow_tab[(log_tab[a] + log_tab[b]) % 255] : 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))

 #define star_x(x) (((x)&0x7f7f7f7f) << 1) ^ ((((x)&0x80808080) >> 7) * 0x1b)

 #define imix_col(y, x)                                                         \
 	do {                                                                       \
 		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);                 \
 	} while (0)

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

 #define loop4(i)                                                               \
 	do {                                                                       \
 		t = ls_box(rotr(t, 8)) ^ 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;                                                  \
 	} while (0)

 #define loop6(i)                                                               \
 	do {                                                                       \
 		t = ls_box(rotr(t, 8)) ^ 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;                                               \
 	} while (0)

 #define loop8(i)                                                               \
 	do {                                                                       \
 		t = ls_box(rotr(t, 8)) ^ 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;                                               \
 	} while (0)

 rijndaelCtx *rijndael_set_key(rijndaelCtx *ctx, const uint32_t *in_key,
 							  const uint32_t key_len, int encrypt)
 {
 	uint32_t i, t, u, v, w;
 	uint32_t *e_key = ctx->e_key;
 	uint32_t *d_key = ctx->d_key;

 	ctx->decrypt = !encrypt;

 	ctx->k_len = (key_len + 31) / 32;

 	e_key[0] = io_swap(in_key[0]);
 	e_key[1] = io_swap(in_key[1]);
 	e_key[2] = io_swap(in_key[2]);
 	e_key[3] = io_swap(in_key[3]);

 	switch (ctx->k_len) {
 	case 4:
 		t = e_key[3];
 		for (i = 0; i < 10; ++i)
 			loop4(i);
 		break;

 	case 6:
 		e_key[4] = io_swap(in_key[4]);
 		t = e_key[5] = io_swap(in_key[5]);
 		for (i = 0; i < 8; ++i)
 			loop6(i);
 		break;

 	case 8:
 		e_key[4] = io_swap(in_key[4]);
 		e_key[5] = io_swap(in_key[5]);
 		e_key[6] = io_swap(in_key[6]);
 		t = e_key[7] = io_swap(in_key[7]);
 		for (i = 0; i < 7; ++i)
 			loop8(i);
 		break;
 	}

 	if (!encrypt) {
 		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 < 4 * ctx->k_len + 24; ++i)
 			imix_col(d_key[i], e_key[i]);
 	}

 	return ctx;
 }

 /* encrypt a block of text	*/

 #define f_nround(bo, bi, k)                                                    \
 	do {                                                                       \
 		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;                                                                \
 	} while (0)

 #define f_lround(bo, bi, k)                                                    \
 	do {                                                                       \
 		f_rl(bo, bi, 0, k);                                                    \
 		f_rl(bo, bi, 1, k);                                                    \
 		f_rl(bo, bi, 2, k);                                                    \
 		f_rl(bo, bi, 3, k);                                                    \
 	} while (0)

 void rijndael_encrypt(rijndaelCtx *ctx, const uint32_t *in_blk,
 					  uint32_t *out_blk)
 {
 	uint32_t k_len = ctx->k_len;
 	uint32_t *e_key = ctx->e_key;
 	uint32_t b0[4], b1[4], *kp;

 	b0[0] = io_swap(in_blk[0]) ^ e_key[0];
 	b0[1] = io_swap(in_blk[1]) ^ e_key[1];
 	b0[2] = io_swap(in_blk[2]) ^ e_key[2];
 	b0[3] = io_swap(in_blk[3]) ^ e_key[3];

 	kp = e_key + 4;

 	if (k_len > 6) {
 		f_nround(b1, b0, kp);
 		f_nround(b0, b1, kp);
 	}

 	if (k_len > 4) {
 		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);

 	out_blk[0] = io_swap(b0[0]);
 	out_blk[1] = io_swap(b0[1]);
 	out_blk[2] = io_swap(b0[2]);
 	out_blk[3] = io_swap(b0[3]);
 }

 /* decrypt a block of text	*/

 #define i_nround(bo, bi, k)                                                    \
 	do {                                                                       \
 		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;                                                                \
 	} while (0)

 #define i_lround(bo, bi, k)                                                    \
 	do {                                                                       \
 		i_rl(bo, bi, 0, k);                                                    \
 		i_rl(bo, bi, 1, k);                                                    \
 		i_rl(bo, bi, 2, k);                                                    \
 		i_rl(bo, bi, 3, k);                                                    \
 	} while (0)

 void rijndael_decrypt(rijndaelCtx *ctx, const uint32_t *in_blk,
 					  uint32_t *out_blk)
 {
 	uint32_t b0[4], b1[4], *kp;
 	uint32_t k_len = ctx->k_len;
 	uint32_t *e_key = ctx->e_key;
 	uint32_t *d_key = ctx->d_key;

 	b0[0] = io_swap(in_blk[0]) ^ e_key[4 * k_len + 24];
 	b0[1] = io_swap(in_blk[1]) ^ e_key[4 * k_len + 25];
 	b0[2] = io_swap(in_blk[2]) ^ e_key[4 * k_len + 26];
 	b0[3] = io_swap(in_blk[3]) ^ e_key[4 * k_len + 27];

 	kp = d_key + 4 * (k_len + 5);

 	if (k_len > 6) {
 		i_nround(b1, b0, kp);
 		i_nround(b0, b1, kp);
 	}

 	if (k_len > 4) {
 		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);

 	out_blk[0] = io_swap(b0[0]);
 	out_blk[1] = io_swap(b0[1]);
 	out_blk[2] = io_swap(b0[2]);
 	out_blk[3] = io_swap(b0[3]);
 }

 /*
  * conventional interface
  *
  * ATM it hopes all data is 4-byte aligned - which
  * should be true for PX.  -marko
  */

 void aes_set_key(rijndaelCtx *ctx, const uint8_t *key, unsigned keybits,
 				 int enc)
 {
 	uint32_t *k;

 	k = (uint32_t *)key;
 	rijndael_set_key(ctx, k, keybits, enc);
 }

 void aes_ecb_encrypt(rijndaelCtx *ctx, uint8_t *data, unsigned len)
 {
 	unsigned bs = 16;
 	uint32_t *d;

 	while (len >= bs) {
 		d = (uint32_t *)data;
 		rijndael_encrypt(ctx, d, d);

 		len -= bs;
 		data += bs;
 	}
 }

 void aes_ecb_decrypt(rijndaelCtx *ctx, uint8_t *data, unsigned len)
 {
 	unsigned bs = 16;
 	uint32_t *d;

 	while (len >= bs) {
 		d = (uint32_t *)data;
 		rijndael_decrypt(ctx, d, d);

 		len -= bs;
 		data += bs;
 	}
 }

 void aes_cbc_encrypt(rijndaelCtx *ctx, uint8_t *iva, uint8_t *data,
 					 unsigned len)
 {
 	uint32_t *iv = (uint32_t *)iva;
 	uint32_t *d = (uint32_t *)data;
 	unsigned bs = 16;

 	while (len >= bs) {
 		d[0] ^= iv[0];
 		d[1] ^= iv[1];
 		d[2] ^= iv[2];
 		d[3] ^= iv[3];

 		rijndael_encrypt(ctx, d, d);

 		iv = d;
 		d += bs / 4;
 		len -= bs;
 	}
 }

 void aes_cbc_decrypt(rijndaelCtx *ctx, uint8_t *iva, uint8_t *data,
 					 unsigned len)
 {
 	uint32_t *d = (uint32_t *)data;
 	unsigned bs = 16;
 	uint32_t buf[4], iv[4];

 	memcpy(iv, iva, bs);
 	while (len >= bs) {
 		buf[0] = d[0];
 		buf[1] = d[1];
 		buf[2] = d[2];
 		buf[3] = d[3];

 		rijndael_decrypt(ctx, buf, d);

 		d[0] ^= iv[0];
 		d[1] ^= iv[1];
 		d[2] ^= iv[2];
 		d[3] ^= iv[3];

 		iv[0] = buf[0];
 		iv[1] = buf[1];
 		iv[2] = buf[2];
 		iv[3] = buf[3];
 		d += 4;
 		len -= bs;
 	}
 }
	/* $OpenBSD: rijndael.c,v 1.6 2000/12/09 18:51:34 markus Exp $ */

	/* contrib/pgcrypto/rijndael.c */

	/* This is an independent implementation of the encryption algorithm: */
	/* */
	/* RIJNDAEL by Joan Daemen and Vincent Rijmen */
	/* */
	/* which is a candidate algorithm in the Advanced Encryption Standard */
	/* programme of the US National Institute of Standards and Technology. */
	/* */
	/* Copyright in this implementation is held by Dr B R Gladman but I */
	/* hereby give permission for its free direct or derivative use subject */
	/* to acknowledgment of its origin and compliance with any conditions */
	/* that the originators of the algorithm place on its exploitation. */
	/* */
	/* Dr Brian Gladman (gladman@seven77.demon.co.uk) 14th January 1999 */

	/* Timing data for Rijndael (rijndael.c)

	Algorithm: rijndael (rijndael.c)

	128 bit key:
	Key Setup: 305/1389 cycles (encrypt/decrypt)
	Encrypt: 374 cycles = 68.4 mbits/sec
	Decrypt: 352 cycles = 72.7 mbits/sec
	Mean: 363 cycles = 70.5 mbits/sec

	192 bit key:
	Key Setup: 277/1595 cycles (encrypt/decrypt)
	Encrypt: 439 cycles = 58.3 mbits/sec
	Decrypt: 425 cycles = 60.2 mbits/sec
	Mean: 432 cycles = 59.3 mbits/sec

	256 bit key:
	Key Setup: 374/1960 cycles (encrypt/decrypt)
	Encrypt: 502 cycles = 51.0 mbits/sec
	Decrypt: 498 cycles = 51.4 mbits/sec
	Mean: 500 cycles = 51.2 mbits/sec

	*/

	#include <random/rijndael.h>

	#include "rijndael.tbl"

	/* 3. Basic macros for speeding up generic operations */

	/* Circular rotate of 32 bit values */

	#define rotr(x, n) (((x) >> ((int)(n))) \| ((x) << (32 - (int)(n))))
	#define rotl(x, n) (((x) << ((int)(n))) \| ((x) >> (32 - (int)(n))))

	/* Invert byte order in a 32 bit variable */

	#define bswap(x) ((rotl((x), 8) & 0x00ff00ff) \| (rotr((x), 8) & 0xff00ff00))

	/* Extract byte from a 32 bit quantity (little endian notation) */

	#define byte(x, n) ((uint8_t)((x) >> (8 * (n))))

	#define io_swap(x) (x)

	#define ff_mult(a, b) \
	((a) && (b) ? pow_tab[(log_tab[a] + log_tab[b]) % 255] : 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))

	#define star_x(x) (((x)&0x7f7f7f7f) << 1) ^ ((((x)&0x80808080) >> 7) * 0x1b)

	#define imix_col(y, x) \
	do { \
	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); \
	} while (0)

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

	#define loop4(i) \
	do { \
	t = ls_box(rotr(t, 8)) ^ 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; \
	} while (0)

	#define loop6(i) \
	do { \
	t = ls_box(rotr(t, 8)) ^ 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; \
	} while (0)

	#define loop8(i) \
	do { \
	t = ls_box(rotr(t, 8)) ^ 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; \
	} while (0)

	rijndaelCtx rijndael_set_key(rijndaelCtx ctx, const uint32_t *in_key,
	const uint32_t key_len, int encrypt)
	{
	uint32_t i, t, u, v, w;
	uint32_t *e_key = ctx->e_key;
	uint32_t *d_key = ctx->d_key;

	ctx->decrypt = !encrypt;

	ctx->k_len = (key_len + 31) / 32;

	e_key[0] = io_swap(in_key[0]);
	e_key[1] = io_swap(in_key[1]);
	e_key[2] = io_swap(in_key[2]);
	e_key[3] = io_swap(in_key[3]);

	switch (ctx->k_len) {
	case 4:
	t = e_key[3];
	for (i = 0; i < 10; ++i)
	loop4(i);
	break;

	case 6:
	e_key[4] = io_swap(in_key[4]);
	t = e_key[5] = io_swap(in_key[5]);
	for (i = 0; i < 8; ++i)
	loop6(i);
	break;

	case 8:
	e_key[4] = io_swap(in_key[4]);
	e_key[5] = io_swap(in_key[5]);
	e_key[6] = io_swap(in_key[6]);
	t = e_key[7] = io_swap(in_key[7]);
	for (i = 0; i < 7; ++i)
	loop8(i);
	break;
	}

	if (!encrypt) {
	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 < 4 * ctx->k_len + 24; ++i)
	imix_col(d_key[i], e_key[i]);
	}

	return ctx;
	}

	/* encrypt a block of text */

	#define f_nround(bo, bi, k) \
	do { \
	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; \
	} while (0)

	#define f_lround(bo, bi, k) \
	do { \
	f_rl(bo, bi, 0, k); \
	f_rl(bo, bi, 1, k); \
	f_rl(bo, bi, 2, k); \
	f_rl(bo, bi, 3, k); \
	} while (0)

	void rijndael_encrypt(rijndaelCtx ctx, const uint32_t in_blk,
	uint32_t *out_blk)
	{
	uint32_t k_len = ctx->k_len;
	uint32_t *e_key = ctx->e_key;
	uint32_t b0[4], b1[4], *kp;

	b0[0] = io_swap(in_blk[0]) ^ e_key[0];
	b0[1] = io_swap(in_blk[1]) ^ e_key[1];
	b0[2] = io_swap(in_blk[2]) ^ e_key[2];
	b0[3] = io_swap(in_blk[3]) ^ e_key[3];

	kp = e_key + 4;

	if (k_len > 6) {
	f_nround(b1, b0, kp);
	f_nround(b0, b1, kp);
	}

	if (k_len > 4) {
	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);

	out_blk[0] = io_swap(b0[0]);
	out_blk[1] = io_swap(b0[1]);
	out_blk[2] = io_swap(b0[2]);
	out_blk[3] = io_swap(b0[3]);
	}

	/* decrypt a block of text */

	#define i_nround(bo, bi, k) \
	do { \
	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; \
	} while (0)

	#define i_lround(bo, bi, k) \
	do { \
	i_rl(bo, bi, 0, k); \
	i_rl(bo, bi, 1, k); \
	i_rl(bo, bi, 2, k); \
	i_rl(bo, bi, 3, k); \
	} while (0)

	void rijndael_decrypt(rijndaelCtx ctx, const uint32_t in_blk,
	uint32_t *out_blk)
	{
	uint32_t b0[4], b1[4], *kp;
	uint32_t k_len = ctx->k_len;
	uint32_t *e_key = ctx->e_key;
	uint32_t *d_key = ctx->d_key;

	b0[0] = io_swap(in_blk[0]) ^ e_key[4 * k_len + 24];
	b0[1] = io_swap(in_blk[1]) ^ e_key[4 * k_len + 25];
	b0[2] = io_swap(in_blk[2]) ^ e_key[4 * k_len + 26];
	b0[3] = io_swap(in_blk[3]) ^ e_key[4 * k_len + 27];

	kp = d_key + 4 * (k_len + 5);

	if (k_len > 6) {
	i_nround(b1, b0, kp);
	i_nround(b0, b1, kp);
	}

	if (k_len > 4) {
	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);

	out_blk[0] = io_swap(b0[0]);
	out_blk[1] = io_swap(b0[1]);
	out_blk[2] = io_swap(b0[2]);
	out_blk[3] = io_swap(b0[3]);
	}

	/*
	* conventional interface
	*
	* ATM it hopes all data is 4-byte aligned - which
	* should be true for PX. -marko
	*/

	void aes_set_key(rijndaelCtx ctx, const uint8_t key, unsigned keybits,
	int enc)
	{
	uint32_t *k;

	k = (uint32_t *)key;
	rijndael_set_key(ctx, k, keybits, enc);
	}

	void aes_ecb_encrypt(rijndaelCtx ctx, uint8_t data, unsigned len)
	{
	unsigned bs = 16;
	uint32_t *d;

	while (len >= bs) {
	d = (uint32_t *)data;
	rijndael_encrypt(ctx, d, d);

	len -= bs;
	data += bs;
	}
	}

	void aes_ecb_decrypt(rijndaelCtx ctx, uint8_t data, unsigned len)
	{
	unsigned bs = 16;
	uint32_t *d;

	while (len >= bs) {
	d = (uint32_t *)data;
	rijndael_decrypt(ctx, d, d);

	len -= bs;
	data += bs;
	}
	}

	void aes_cbc_encrypt(rijndaelCtx ctx, uint8_t iva, uint8_t *data,
	unsigned len)
	{
	uint32_t iv = (uint32_t )iva;
	uint32_t d = (uint32_t )data;
	unsigned bs = 16;

	while (len >= bs) {
	d[0] ^= iv[0];
	d[1] ^= iv[1];
	d[2] ^= iv[2];
	d[3] ^= iv[3];

	rijndael_encrypt(ctx, d, d);

	iv = d;
	d += bs / 4;
	len -= bs;
	}
	}

	void aes_cbc_decrypt(rijndaelCtx ctx, uint8_t iva, uint8_t *data,
	unsigned len)
	{
	uint32_t d = (uint32_t )data;
	unsigned bs = 16;
	uint32_t buf[4], iv[4];

	memcpy(iv, iva, bs);
	while (len >= bs) {
	buf[0] = d[0];
	buf[1] = d[1];
	buf[2] = d[2];
	buf[3] = d[3];

	rijndael_decrypt(ctx, buf, d);

	d[0] ^= iv[0];
	d[1] ^= iv[1];
	d[2] ^= iv[2];
	d[3] ^= iv[3];

	iv[0] = buf[0];
	iv[1] = buf[1];
	iv[2] = buf[2];
	iv[3] = buf[3];
	d += 4;
	len -= bs;
	}
	}