1121257Sume/*	$KAME: rijndael-api-fst.c,v 1.10 2001/05/27 09:34:18 itojun Exp $	*/
267957Skris
3121257Sume/*
4121257Sume * rijndael-api-fst.c   v2.3   April '2000
567957Skris *
6121257Sume * Optimised ANSI C code
767957Skris *
8121257Sume * authors: v1.0: Antoon Bosselaers
9121257Sume *          v2.0: Vincent Rijmen
10121257Sume *          v2.1: Vincent Rijmen
11121257Sume *          v2.2: Vincent Rijmen
12121257Sume *          v2.3: Paulo Barreto
13121257Sume *          v2.4: Vincent Rijmen
1467957Skris *
15121257Sume * This code is placed in the public domain.
1667957Skris */
1767957Skris
18116174Sobrien#include <sys/cdefs.h>
19116174Sobrien__FBSDID("$FreeBSD: releng/11.0/sys/crypto/rijndael/rijndael-api-fst.c 274380 2014-11-11 13:37:28Z des $");
20116174Sobrien
2167957Skris#include <sys/param.h>
2278064Sume#ifdef _KERNEL
2367957Skris#include <sys/systm.h>
2478064Sume#else
2578064Sume#include <string.h>
2678064Sume#endif
27122410Sume
28122410Sume#include <crypto/rijndael/rijndael_local.h>
2967957Skris#include <crypto/rijndael/rijndael-api-fst.h>
3067957Skris
31121257Sume#ifndef TRUE
32121257Sume#define TRUE 1
33121257Sume#endif
34121257Sume
35121257Sumetypedef u_int8_t	BYTE;
36121257Sume
37274340Sdesint rijndael_makeKey(keyInstance *key, BYTE direction, int keyLen,
38274340Sdes	const char *keyMaterial) {
39122410Sume	u_int8_t cipherKey[RIJNDAEL_MAXKB];
40122410Sume
4167957Skris	if (key == NULL) {
4267957Skris		return BAD_KEY_INSTANCE;
4367957Skris	}
4467957Skris
4567957Skris	if ((direction == DIR_ENCRYPT) || (direction == DIR_DECRYPT)) {
4667957Skris		key->direction = direction;
4767957Skris	} else {
4867957Skris		return BAD_KEY_DIR;
4967957Skris	}
5067957Skris
51122410Sume	if ((keyLen == 128) || (keyLen == 192) || (keyLen == 256)) {
5267957Skris		key->keyLen = keyLen;
5367957Skris	} else {
5467957Skris		return BAD_KEY_MAT;
5567957Skris	}
5667957Skris
5767957Skris	if (keyMaterial != NULL) {
58122410Sume		memcpy(key->keyMaterial, keyMaterial, keyLen/8);
5967957Skris	}
6067957Skris
6167957Skris	/* initialize key schedule: */
62122410Sume	memcpy(cipherKey, key->keyMaterial, keyLen/8);
63122410Sume	if (direction == DIR_ENCRYPT) {
64122410Sume		key->Nr = rijndaelKeySetupEnc(key->rk, cipherKey, keyLen);
65122410Sume	} else {
66122410Sume		key->Nr = rijndaelKeySetupDec(key->rk, cipherKey, keyLen);
6767957Skris	}
68122410Sume	rijndaelKeySetupEnc(key->ek, cipherKey, keyLen);
6967957Skris	return TRUE;
7067957Skris}
7167957Skris
7267957Skrisint rijndael_cipherInit(cipherInstance *cipher, BYTE mode, char *IV) {
7367957Skris	if ((mode == MODE_ECB) || (mode == MODE_CBC) || (mode == MODE_CFB1)) {
7467957Skris		cipher->mode = mode;
7567957Skris	} else {
7667957Skris		return BAD_CIPHER_MODE;
7767957Skris	}
7867957Skris	if (IV != NULL) {
79122410Sume		memcpy(cipher->IV, IV, RIJNDAEL_MAX_IV_SIZE);
8067957Skris	} else {
81122410Sume		memset(cipher->IV, 0, RIJNDAEL_MAX_IV_SIZE);
8267957Skris	}
8367957Skris	return TRUE;
8467957Skris}
8567957Skris
8667957Skrisint rijndael_blockEncrypt(cipherInstance *cipher, keyInstance *key,
87274340Sdes		const BYTE *input, int inputLen, BYTE *outBuffer) {
88121257Sume	int i, k, numBlocks;
89122410Sume	u_int8_t block[16], iv[4][4];
9067957Skris
9167957Skris	if (cipher == NULL ||
9267957Skris		key == NULL ||
9367957Skris		key->direction == DIR_DECRYPT) {
9467957Skris		return BAD_CIPHER_STATE;
9567957Skris	}
9667957Skris	if (input == NULL || inputLen <= 0) {
9767957Skris		return 0; /* nothing to do */
9867957Skris	}
9967957Skris
10067957Skris	numBlocks = inputLen/128;
101122410Sume
10267957Skris	switch (cipher->mode) {
103122410Sume	case MODE_ECB:
10467957Skris		for (i = numBlocks; i > 0; i--) {
105122410Sume			rijndaelEncrypt(key->rk, key->Nr, input, outBuffer);
10667957Skris			input += 16;
10767957Skris			outBuffer += 16;
10867957Skris		}
10967957Skris		break;
110122410Sume
11167957Skris	case MODE_CBC:
112121085Sume#if 1 /*STRICT_ALIGN*/
113122410Sume		memcpy(block, cipher->IV, 16);
114122410Sume		memcpy(iv, input, 16);
115122410Sume		((u_int32_t*)block)[0] ^= ((u_int32_t*)iv)[0];
116122410Sume		((u_int32_t*)block)[1] ^= ((u_int32_t*)iv)[1];
117122410Sume		((u_int32_t*)block)[2] ^= ((u_int32_t*)iv)[2];
118122410Sume		((u_int32_t*)block)[3] ^= ((u_int32_t*)iv)[3];
119121085Sume#else
120122410Sume		((u_int32_t*)block)[0] = ((u_int32_t*)cipher->IV)[0] ^ ((u_int32_t*)input)[0];
121122410Sume		((u_int32_t*)block)[1] = ((u_int32_t*)cipher->IV)[1] ^ ((u_int32_t*)input)[1];
122122410Sume		((u_int32_t*)block)[2] = ((u_int32_t*)cipher->IV)[2] ^ ((u_int32_t*)input)[2];
123122410Sume		((u_int32_t*)block)[3] = ((u_int32_t*)cipher->IV)[3] ^ ((u_int32_t*)input)[3];
124121085Sume#endif
125122410Sume		rijndaelEncrypt(key->rk, key->Nr, block, outBuffer);
126121257Sume		input += 16;
127121257Sume		for (i = numBlocks - 1; i > 0; i--) {
128121085Sume#if 1 /*STRICT_ALIGN*/
129122410Sume			memcpy(block, outBuffer, 16);
130122410Sume			memcpy(iv, input, 16);
131122410Sume			((u_int32_t*)block)[0] ^= ((u_int32_t*)iv)[0];
132122410Sume			((u_int32_t*)block)[1] ^= ((u_int32_t*)iv)[1];
133122410Sume			((u_int32_t*)block)[2] ^= ((u_int32_t*)iv)[2];
134122410Sume			((u_int32_t*)block)[3] ^= ((u_int32_t*)iv)[3];
135121085Sume#else
136122410Sume			((u_int32_t*)block)[0] = ((u_int32_t*)outBuffer)[0] ^ ((u_int32_t*)input)[0];
137122410Sume			((u_int32_t*)block)[1] = ((u_int32_t*)outBuffer)[1] ^ ((u_int32_t*)input)[1];
138122410Sume			((u_int32_t*)block)[2] = ((u_int32_t*)outBuffer)[2] ^ ((u_int32_t*)input)[2];
139122410Sume			((u_int32_t*)block)[3] = ((u_int32_t*)outBuffer)[3] ^ ((u_int32_t*)input)[3];
140121085Sume#endif
141121257Sume			outBuffer += 16;
142122410Sume			rijndaelEncrypt(key->rk, key->Nr, block, outBuffer);
143121050Sume			input += 16;
14467957Skris		}
14567957Skris		break;
146122410Sume
147121257Sume	case MODE_CFB1:
148121085Sume#if 1 /*STRICT_ALIGN*/
149122410Sume		memcpy(iv, cipher->IV, 16);
150121257Sume#else  /* !STRICT_ALIGN */
151122410Sume		*((u_int32_t*)iv[0]) = *((u_int32_t*)(cipher->IV   ));
152122410Sume		*((u_int32_t*)iv[1]) = *((u_int32_t*)(cipher->IV+ 4));
153122410Sume		*((u_int32_t*)iv[2]) = *((u_int32_t*)(cipher->IV+ 8));
154122410Sume		*((u_int32_t*)iv[3]) = *((u_int32_t*)(cipher->IV+12));
155121257Sume#endif /* ?STRICT_ALIGN */
156121257Sume		for (i = numBlocks; i > 0; i--) {
157121257Sume			for (k = 0; k < 128; k++) {
158122410Sume				*((u_int32_t*) block    ) = *((u_int32_t*)iv[0]);
159122410Sume				*((u_int32_t*)(block+ 4)) = *((u_int32_t*)iv[1]);
160122410Sume				*((u_int32_t*)(block+ 8)) = *((u_int32_t*)iv[2]);
161122410Sume				*((u_int32_t*)(block+12)) = *((u_int32_t*)iv[3]);
162122410Sume				rijndaelEncrypt(key->ek, key->Nr, block,
163122410Sume				    block);
164121257Sume				outBuffer[k/8] ^= (block[0] & 0x80) >> (k & 7);
165121257Sume				iv[0][0] = (iv[0][0] << 1) | (iv[0][1] >> 7);
166121257Sume				iv[0][1] = (iv[0][1] << 1) | (iv[0][2] >> 7);
167121257Sume				iv[0][2] = (iv[0][2] << 1) | (iv[0][3] >> 7);
168121257Sume				iv[0][3] = (iv[0][3] << 1) | (iv[1][0] >> 7);
169121257Sume				iv[1][0] = (iv[1][0] << 1) | (iv[1][1] >> 7);
170121257Sume				iv[1][1] = (iv[1][1] << 1) | (iv[1][2] >> 7);
171121257Sume				iv[1][2] = (iv[1][2] << 1) | (iv[1][3] >> 7);
172121257Sume				iv[1][3] = (iv[1][3] << 1) | (iv[2][0] >> 7);
173121257Sume				iv[2][0] = (iv[2][0] << 1) | (iv[2][1] >> 7);
174121257Sume				iv[2][1] = (iv[2][1] << 1) | (iv[2][2] >> 7);
175121257Sume				iv[2][2] = (iv[2][2] << 1) | (iv[2][3] >> 7);
176121257Sume				iv[2][3] = (iv[2][3] << 1) | (iv[3][0] >> 7);
177121257Sume				iv[3][0] = (iv[3][0] << 1) | (iv[3][1] >> 7);
178121257Sume				iv[3][1] = (iv[3][1] << 1) | (iv[3][2] >> 7);
179121257Sume				iv[3][2] = (iv[3][2] << 1) | (iv[3][3] >> 7);
180121257Sume				iv[3][3] = (iv[3][3] << 1) | ((outBuffer[k/8] >> (7-(k&7))) & 1);
181121257Sume			}
182121257Sume		}
183121257Sume		break;
184122410Sume
18567957Skris	default:
18667957Skris		return BAD_CIPHER_STATE;
18767957Skris	}
188122410Sume
18967957Skris	return 128*numBlocks;
19067957Skris}
19167957Skris
19267957Skris/**
19367957Skris * Encrypt data partitioned in octets, using RFC 2040-like padding.
19467957Skris *
19567957Skris * @param   input           data to be encrypted (octet sequence)
19667957Skris * @param   inputOctets		input length in octets (not bits)
19767957Skris * @param   outBuffer       encrypted output data
19867957Skris *
19967957Skris * @return	length in octets (not bits) of the encrypted output buffer.
20067957Skris */
20167957Skrisint rijndael_padEncrypt(cipherInstance *cipher, keyInstance *key,
202274340Sdes		const BYTE *input, int inputOctets, BYTE *outBuffer) {
20367957Skris	int i, numBlocks, padLen;
204122410Sume	u_int8_t block[16], *iv, *cp;
20567957Skris
20667957Skris	if (cipher == NULL ||
20767957Skris		key == NULL ||
20867957Skris		key->direction == DIR_DECRYPT) {
20967957Skris		return BAD_CIPHER_STATE;
21067957Skris	}
21167957Skris	if (input == NULL || inputOctets <= 0) {
21267957Skris		return 0; /* nothing to do */
21367957Skris	}
21467957Skris
21567957Skris	numBlocks = inputOctets/16;
21667957Skris
21767957Skris	switch (cipher->mode) {
218122410Sume	case MODE_ECB:
21967957Skris		for (i = numBlocks; i > 0; i--) {
220122410Sume			rijndaelEncrypt(key->rk, key->Nr, input, outBuffer);
22167957Skris			input += 16;
22267957Skris			outBuffer += 16;
22367957Skris		}
22467957Skris		padLen = 16 - (inputOctets - 16*numBlocks);
225120157Sume		if (padLen <= 0 || padLen > 16)
226105099Sphk			return BAD_CIPHER_STATE;
227122410Sume		memcpy(block, input, 16 - padLen);
228121257Sume		for (cp = block + 16 - padLen; cp < block + 16; cp++)
229121257Sume			*cp = padLen;
230122410Sume		rijndaelEncrypt(key->rk, key->Nr, block, outBuffer);
23167957Skris		break;
23267957Skris
23367957Skris	case MODE_CBC:
23467957Skris		iv = cipher->IV;
23567957Skris		for (i = numBlocks; i > 0; i--) {
236274380Sdes			((u_int32_t*)block)[0] = ((const u_int32_t*)input)[0] ^ ((u_int32_t*)iv)[0];
237274380Sdes			((u_int32_t*)block)[1] = ((const u_int32_t*)input)[1] ^ ((u_int32_t*)iv)[1];
238274380Sdes			((u_int32_t*)block)[2] = ((const u_int32_t*)input)[2] ^ ((u_int32_t*)iv)[2];
239274380Sdes			((u_int32_t*)block)[3] = ((const u_int32_t*)input)[3] ^ ((u_int32_t*)iv)[3];
240122410Sume			rijndaelEncrypt(key->rk, key->Nr, block, outBuffer);
24167957Skris			iv = outBuffer;
24267957Skris			input += 16;
24367957Skris			outBuffer += 16;
24467957Skris		}
24567957Skris		padLen = 16 - (inputOctets - 16*numBlocks);
246120206Sume		if (padLen <= 0 || padLen > 16)
247105099Sphk			return BAD_CIPHER_STATE;
24867957Skris		for (i = 0; i < 16 - padLen; i++) {
24967957Skris			block[i] = input[i] ^ iv[i];
25067957Skris		}
25167957Skris		for (i = 16 - padLen; i < 16; i++) {
25267957Skris			block[i] = (BYTE)padLen ^ iv[i];
25367957Skris		}
254122410Sume		rijndaelEncrypt(key->rk, key->Nr, block, outBuffer);
25567957Skris		break;
25667957Skris
25767957Skris	default:
25867957Skris		return BAD_CIPHER_STATE;
25967957Skris	}
26067957Skris
26167957Skris	return 16*(numBlocks + 1);
26267957Skris}
26367957Skris
26467957Skrisint rijndael_blockDecrypt(cipherInstance *cipher, keyInstance *key,
265274340Sdes		const BYTE *input, int inputLen, BYTE *outBuffer) {
266121257Sume	int i, k, numBlocks;
267122410Sume	u_int8_t block[16], iv[4][4];
26867957Skris
26967957Skris	if (cipher == NULL ||
27067957Skris		key == NULL ||
27167957Skris		(cipher->mode != MODE_CFB1 && key->direction == DIR_ENCRYPT)) {
27267957Skris		return BAD_CIPHER_STATE;
27367957Skris	}
27467957Skris	if (input == NULL || inputLen <= 0) {
27567957Skris		return 0; /* nothing to do */
27667957Skris	}
27767957Skris
27867957Skris	numBlocks = inputLen/128;
27967957Skris
28067957Skris	switch (cipher->mode) {
281122410Sume	case MODE_ECB:
282122410Sume		for (i = numBlocks; i > 0; i--) {
283122410Sume			rijndaelDecrypt(key->rk, key->Nr, input, outBuffer);
28467957Skris			input += 16;
28567957Skris			outBuffer += 16;
28667957Skris		}
28767957Skris		break;
288122410Sume
28967957Skris	case MODE_CBC:
290121257Sume#if 1 /*STRICT_ALIGN */
291122410Sume		memcpy(iv, cipher->IV, 16);
292121085Sume#else
293122410Sume		*((u_int32_t*)iv[0]) = *((u_int32_t*)(cipher->IV   ));
294122410Sume		*((u_int32_t*)iv[1]) = *((u_int32_t*)(cipher->IV+ 4));
295122410Sume		*((u_int32_t*)iv[2]) = *((u_int32_t*)(cipher->IV+ 8));
296122410Sume		*((u_int32_t*)iv[3]) = *((u_int32_t*)(cipher->IV+12));
297121085Sume#endif
29867957Skris		for (i = numBlocks; i > 0; i--) {
299122410Sume			rijndaelDecrypt(key->rk, key->Nr, input, block);
300122410Sume			((u_int32_t*)block)[0] ^= *((u_int32_t*)iv[0]);
301122410Sume			((u_int32_t*)block)[1] ^= *((u_int32_t*)iv[1]);
302122410Sume			((u_int32_t*)block)[2] ^= *((u_int32_t*)iv[2]);
303122410Sume			((u_int32_t*)block)[3] ^= *((u_int32_t*)iv[3]);
304121085Sume#if 1 /*STRICT_ALIGN*/
305122410Sume			memcpy(iv, input, 16);
306122410Sume			memcpy(outBuffer, block, 16);
307121085Sume#else
308122410Sume			*((u_int32_t*)iv[0]) = ((u_int32_t*)input)[0]; ((u_int32_t*)outBuffer)[0] = ((u_int32_t*)block)[0];
309122410Sume			*((u_int32_t*)iv[1]) = ((u_int32_t*)input)[1]; ((u_int32_t*)outBuffer)[1] = ((u_int32_t*)block)[1];
310122410Sume			*((u_int32_t*)iv[2]) = ((u_int32_t*)input)[2]; ((u_int32_t*)outBuffer)[2] = ((u_int32_t*)block)[2];
311122410Sume			*((u_int32_t*)iv[3]) = ((u_int32_t*)input)[3]; ((u_int32_t*)outBuffer)[3] = ((u_int32_t*)block)[3];
312121085Sume#endif
31367957Skris			input += 16;
31467957Skris			outBuffer += 16;
31567957Skris		}
31667957Skris		break;
317122410Sume
318121257Sume	case MODE_CFB1:
319121257Sume#if 1 /*STRICT_ALIGN */
320122410Sume		memcpy(iv, cipher->IV, 16);
321121085Sume#else
322122410Sume		*((u_int32_t*)iv[0]) = *((u_int32_t*)(cipher->IV));
323122410Sume		*((u_int32_t*)iv[1]) = *((u_int32_t*)(cipher->IV+ 4));
324122410Sume		*((u_int32_t*)iv[2]) = *((u_int32_t*)(cipher->IV+ 8));
325122410Sume		*((u_int32_t*)iv[3]) = *((u_int32_t*)(cipher->IV+12));
326121085Sume#endif
327121257Sume		for (i = numBlocks; i > 0; i--) {
328121257Sume			for (k = 0; k < 128; k++) {
329122410Sume				*((u_int32_t*) block    ) = *((u_int32_t*)iv[0]);
330122410Sume				*((u_int32_t*)(block+ 4)) = *((u_int32_t*)iv[1]);
331122410Sume				*((u_int32_t*)(block+ 8)) = *((u_int32_t*)iv[2]);
332122410Sume				*((u_int32_t*)(block+12)) = *((u_int32_t*)iv[3]);
333122410Sume				rijndaelEncrypt(key->ek, key->Nr, block,
334122410Sume				    block);
335121257Sume				iv[0][0] = (iv[0][0] << 1) | (iv[0][1] >> 7);
336121257Sume				iv[0][1] = (iv[0][1] << 1) | (iv[0][2] >> 7);
337121257Sume				iv[0][2] = (iv[0][2] << 1) | (iv[0][3] >> 7);
338121257Sume				iv[0][3] = (iv[0][3] << 1) | (iv[1][0] >> 7);
339121257Sume				iv[1][0] = (iv[1][0] << 1) | (iv[1][1] >> 7);
340121257Sume				iv[1][1] = (iv[1][1] << 1) | (iv[1][2] >> 7);
341121257Sume				iv[1][2] = (iv[1][2] << 1) | (iv[1][3] >> 7);
342121257Sume				iv[1][3] = (iv[1][3] << 1) | (iv[2][0] >> 7);
343121257Sume				iv[2][0] = (iv[2][0] << 1) | (iv[2][1] >> 7);
344121257Sume				iv[2][1] = (iv[2][1] << 1) | (iv[2][2] >> 7);
345121257Sume				iv[2][2] = (iv[2][2] << 1) | (iv[2][3] >> 7);
346121257Sume				iv[2][3] = (iv[2][3] << 1) | (iv[3][0] >> 7);
347121257Sume				iv[3][0] = (iv[3][0] << 1) | (iv[3][1] >> 7);
348121257Sume				iv[3][1] = (iv[3][1] << 1) | (iv[3][2] >> 7);
349121257Sume				iv[3][2] = (iv[3][2] << 1) | (iv[3][3] >> 7);
350121257Sume				iv[3][3] = (iv[3][3] << 1) | ((input[k/8] >> (7-(k&7))) & 1);
351121257Sume				outBuffer[k/8] ^= (block[0] & 0x80) >> (k & 7);
352121257Sume			}
353121257Sume		}
354121257Sume		break;
355121050Sume
35667957Skris	default:
35767957Skris		return BAD_CIPHER_STATE;
35867957Skris	}
359122410Sume
36067957Skris	return 128*numBlocks;
36167957Skris}
36267957Skris
36367957Skrisint rijndael_padDecrypt(cipherInstance *cipher, keyInstance *key,
364274340Sdes		const BYTE *input, int inputOctets, BYTE *outBuffer) {
36567957Skris	int i, numBlocks, padLen;
366122410Sume	u_int8_t block[16];
367122410Sume	u_int32_t iv[4];
36867957Skris
36967957Skris	if (cipher == NULL ||
37067957Skris		key == NULL ||
37167957Skris		key->direction == DIR_ENCRYPT) {
37267957Skris		return BAD_CIPHER_STATE;
37367957Skris	}
37467957Skris	if (input == NULL || inputOctets <= 0) {
37567957Skris		return 0; /* nothing to do */
37667957Skris	}
37767957Skris	if (inputOctets % 16 != 0) {
37867957Skris		return BAD_DATA;
37967957Skris	}
38067957Skris
38167957Skris	numBlocks = inputOctets/16;
38267957Skris
38367957Skris	switch (cipher->mode) {
38467957Skris	case MODE_ECB:
38567957Skris		/* all blocks but last */
386122410Sume		for (i = numBlocks - 1; i > 0; i--) {
387122410Sume			rijndaelDecrypt(key->rk, key->Nr, input, outBuffer);
38867957Skris			input += 16;
38967957Skris			outBuffer += 16;
39067957Skris		}
39167957Skris		/* last block */
392122410Sume		rijndaelDecrypt(key->rk, key->Nr, input, block);
39367957Skris		padLen = block[15];
39467957Skris		if (padLen >= 16) {
39567957Skris			return BAD_DATA;
39667957Skris		}
39767957Skris		for (i = 16 - padLen; i < 16; i++) {
39867957Skris			if (block[i] != padLen) {
39967957Skris				return BAD_DATA;
40067957Skris			}
40167957Skris		}
402122410Sume		memcpy(outBuffer, block, 16 - padLen);
40367957Skris		break;
404122410Sume
40567957Skris	case MODE_CBC:
406122410Sume		memcpy(iv, cipher->IV, 16);
40767957Skris		/* all blocks but last */
40867957Skris		for (i = numBlocks - 1; i > 0; i--) {
409122410Sume			rijndaelDecrypt(key->rk, key->Nr, input, block);
410122410Sume			((u_int32_t*)block)[0] ^= iv[0];
411122410Sume			((u_int32_t*)block)[1] ^= iv[1];
412122410Sume			((u_int32_t*)block)[2] ^= iv[2];
413122410Sume			((u_int32_t*)block)[3] ^= iv[3];
414122410Sume			memcpy(iv, input, 16);
415122410Sume			memcpy(outBuffer, block, 16);
41667957Skris			input += 16;
41767957Skris			outBuffer += 16;
41867957Skris		}
41967957Skris		/* last block */
420122410Sume		rijndaelDecrypt(key->rk, key->Nr, input, block);
421122410Sume		((u_int32_t*)block)[0] ^= iv[0];
422122410Sume		((u_int32_t*)block)[1] ^= iv[1];
423122410Sume		((u_int32_t*)block)[2] ^= iv[2];
424122410Sume		((u_int32_t*)block)[3] ^= iv[3];
42567957Skris		padLen = block[15];
42667957Skris		if (padLen <= 0 || padLen > 16) {
42767957Skris			return BAD_DATA;
42867957Skris		}
42967957Skris		for (i = 16 - padLen; i < 16; i++) {
43067957Skris			if (block[i] != padLen) {
43167957Skris				return BAD_DATA;
43267957Skris			}
43367957Skris		}
434122410Sume		memcpy(outBuffer, block, 16 - padLen);
43567957Skris		break;
436122410Sume
43767957Skris	default:
43867957Skris		return BAD_CIPHER_STATE;
43967957Skris	}
440122410Sume
44167957Skris	return 16*numBlocks - padLen;
44267957Skris}
443