/* crypto/asn1/a_utf8.c */

/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)

 * All rights reserved.

 *

 * This package is an SSL implementation written

 * by Eric Young (eay@cryptsoft.com).

 * The implementation was written so as to conform with Netscapes SSL.

 * 

 * This library is free for commercial and non-commercial use as long as

 * the following conditions are aheared to.  The following conditions

 * apply to all code found in this distribution, be it the RC4, RSA,

 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation

 * included with this distribution is covered by the same copyright terms

 * except that the holder is Tim Hudson (tjh@cryptsoft.com).

 * 

 * Copyright remains Eric Young's, and as such any Copyright notices in

 * the code are not to be removed.

 * If this package is used in a product, Eric Young should be given attribution

 * as the author of the parts of the library used.

 * This can be in the form of a textual message at program startup or

 * in documentation (online or textual) provided with the package.

 * 

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. All advertising materials mentioning features or use of this software

 *    must display the following acknowledgement:

 *    "This product includes cryptographic software written by

 *     Eric Young (eay@cryptsoft.com)"

 *    The word 'cryptographic' can be left out if the rouines from the library

 *    being used are not cryptographic related :-).

 * 4. If you include any Windows specific code (or a derivative thereof) from 

 *    the apps directory (application code) you must include an acknowledgement:

 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"

 * 

 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 * 

 * The licence and distribution terms for any publically available version or

 * derivative of this code cannot be changed.  i.e. this code cannot simply be

 * copied and put under another distribution licence

 * [including the GNU Public Licence.]

 */

#include <stdio.h>

#include "cryptlib.h"

#include <openssl/asn1.h>

/* UTF8 utilities */

/* This parses a UTF8 string one character at a time. It is passed a pointer

 * to the string and the length of the string. It sets 'value' to the value of

 * the current character. It returns the number of characters read or a

 * negative error code:

 * -1 = string too short

 * -2 = illegal character

 * -3 = subsequent characters not of the form 10xxxxxx

 * -4 = character encoded incorrectly (not minimal length).

 */

EXPORT_C int UTF8_getc(const unsigned char *str, int len, unsigned long *val)

{

	const unsigned char *p;

	unsigned long value;

	int ret;

	if(len <= 0) return 0;

	p = str;

	/* Check syntax and work out the encoded value (if correct) */

	if((*p & 0x80) == 0) {

		value = *p++ & 0x7f;

		ret = 1;

	} else if((*p & 0xe0) == 0xc0) {

		if(len < 2) return -1;

		if((p[1] & 0xc0) != 0x80) return -3;

		value = (*p++ & 0x1f) << 6;

		value |= *p++ & 0x3f;

		if(value < 0x80) return -4;

		ret = 2;

	} else if((*p & 0xf0) == 0xe0) {

		if(len < 3) return -1;

		if( ((p[1] & 0xc0) != 0x80)

		   || ((p[2] & 0xc0) != 0x80) ) return -3;

		value = (*p++ & 0xf) << 12;

		value |= (*p++ & 0x3f) << 6;

		value |= *p++ & 0x3f;

		if(value < 0x800) return -4;

		ret = 3;

	} else if((*p & 0xf8) == 0xf0) {

		if(len < 4) return -1;

		if( ((p[1] & 0xc0) != 0x80)

		   || ((p[2] & 0xc0) != 0x80) 

		   || ((p[3] & 0xc0) != 0x80) ) return -3;

		value = ((unsigned long)(*p++ & 0x7)) << 18;

		value |= (*p++ & 0x3f) << 12;

		value |= (*p++ & 0x3f) << 6;

		value |= *p++ & 0x3f;

		if(value < 0x10000) return -4;

		ret = 4;

	} else if((*p & 0xfc) == 0xf8) {

		if(len < 5) return -1;

		if( ((p[1] & 0xc0) != 0x80)

		   || ((p[2] & 0xc0) != 0x80) 

		   || ((p[3] & 0xc0) != 0x80) 

		   || ((p[4] & 0xc0) != 0x80) ) return -3;

		value = ((unsigned long)(*p++ & 0x3)) << 24;

		value |= ((unsigned long)(*p++ & 0x3f)) << 18;

		value |= ((unsigned long)(*p++ & 0x3f)) << 12;

		value |= (*p++ & 0x3f) << 6;

		value |= *p++ & 0x3f;

		if(value < 0x200000) return -4;

		ret = 5;

	} else if((*p & 0xfe) == 0xfc) {

		if(len < 6) return -1;

		if( ((p[1] & 0xc0) != 0x80)

		   || ((p[2] & 0xc0) != 0x80) 

		   || ((p[3] & 0xc0) != 0x80) 

		   || ((p[4] & 0xc0) != 0x80) 

		   || ((p[5] & 0xc0) != 0x80) ) return -3;

		value = ((unsigned long)(*p++ & 0x1)) << 30;

		value |= ((unsigned long)(*p++ & 0x3f)) << 24;

		value |= ((unsigned long)(*p++ & 0x3f)) << 18;

		value |= ((unsigned long)(*p++ & 0x3f)) << 12;

		value |= (*p++ & 0x3f) << 6;

		value |= *p++ & 0x3f;

		if(value < 0x4000000) return -4;

		ret = 6;

	} else return -2;

	*val = value;

	return ret;

}

/* This takes a character 'value' and writes the UTF8 encoded value in

 * 'str' where 'str' is a buffer containing 'len' characters. Returns

 * the number of characters written or -1 if 'len' is too small. 'str' can

 * be set to NULL in which case it just returns the number of characters.

 * It will need at most 6 characters.

 */

EXPORT_C int UTF8_putc(unsigned char *str, int len, unsigned long value)

{

	if(!str) len = 6;	/* Maximum we will need */

	else if(len <= 0) return -1;

	if(value < 0x80) {

		if(str) *str = (unsigned char)value;

		return 1;

	}

	if(value < 0x800) {

		if(len < 2) return -1;

		if(str) {

			*str++ = (unsigned char)(((value >> 6) & 0x1f) | 0xc0);

			*str = (unsigned char)((value & 0x3f) | 0x80);

		}

		return 2;

	}

	if(value < 0x10000) {

		if(len < 3) return -1;

		if(str) {

			*str++ = (unsigned char)(((value >> 12) & 0xf) | 0xe0);

			*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);

			*str = (unsigned char)((value & 0x3f) | 0x80);

		}

		return 3;

	}

	if(value < 0x200000) {

		if(len < 4) return -1;

		if(str) {

			*str++ = (unsigned char)(((value >> 18) & 0x7) | 0xf0);

			*str++ = (unsigned char)(((value >> 12) & 0x3f) | 0x80);

			*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);

			*str = (unsigned char)((value & 0x3f) | 0x80);

		}

		return 4;

	}

	if(value < 0x4000000) {

		if(len < 5) return -1;

		if(str) {

			*str++ = (unsigned char)(((value >> 24) & 0x3) | 0xf8);

			*str++ = (unsigned char)(((value >> 18) & 0x3f) | 0x80);

			*str++ = (unsigned char)(((value >> 12) & 0x3f) | 0x80);

			*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);

			*str = (unsigned char)((value & 0x3f) | 0x80);

		}

		return 5;

	}

	if(len < 6) return -1;

	if(str) {

		*str++ = (unsigned char)(((value >> 30) & 0x1) | 0xfc);

		*str++ = (unsigned char)(((value >> 24) & 0x3f) | 0x80);

		*str++ = (unsigned char)(((value >> 18) & 0x3f) | 0x80);

		*str++ = (unsigned char)(((value >> 12) & 0x3f) | 0x80);

		*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);

		*str = (unsigned char)((value & 0x3f) | 0x80);

	}

	return 6;

}