105 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			105 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (c) 2004-2005 Kungliga Tekniska Högskolan
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|  * (Royal Institute of Technology, Stockholm, Sweden).
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|  * All rights reserved.
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|  *
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|  * Redistribution and use in source and binary forms, with or without
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|  * modification, are permitted provided that the following conditions
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|  * are met:
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|  *
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|  * 1. Redistributions of source code must retain the above copyright
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|  *    notice, this list of conditions and the following disclaimer.
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|  *
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|  * 2. Redistributions in binary form must reproduce the above copyright
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|  *    notice, this list of conditions and the following disclaimer in the
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|  *    documentation and/or other materials provided with the distribution.
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|  *
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|  * 3. Neither the name of the Institute nor the names of its contributors
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|  *    may be used to endorse or promote products derived from this software
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|  *    without specific prior written permission.
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|  *
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|  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
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|  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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|  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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|  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
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|  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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|  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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|  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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|  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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|  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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|  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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|  * SUCH DAMAGE.
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|  */
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| 
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| 
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| #include <config.h>
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| #include "roken.h"
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| #include <ctype.h>
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| #include "hex.h"
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| 
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| static const char hexchar[16] = "0123456789ABCDEF";
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| 
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| static int
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| pos(char c)
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| {
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|     const char *p;
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|     c = toupper((unsigned char)c);
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|     for (p = hexchar; *p; p++)
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| 	if (*p == c)
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| 	    return p - hexchar;
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|     return -1;
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| }
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| 
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| ROKEN_LIB_FUNCTION ssize_t ROKEN_LIB_CALL
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| hex_encode(const void *data, size_t size, char **str)
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| {
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|     const unsigned char *q = data;
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|     size_t i;
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|     char *p;
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| 
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|     /* check for overflow */
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|     if (size * 2 < size) {
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|         *str = NULL;
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| 	return -1;
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|     }
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| 
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|     p = malloc(size * 2 + 1);
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|     if (p == NULL) {
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|         *str = NULL;
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| 	return -1;
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|     }
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| 
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|     for (i = 0; i < size; i++) {
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| 	p[i * 2] = hexchar[(*q >> 4) & 0xf];
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| 	p[i * 2 + 1] = hexchar[*q & 0xf];
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| 	q++;
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|     }
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|     p[i * 2] = '\0';
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|     *str = p;
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| 
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|     return i * 2;
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| }
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| 
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| ROKEN_LIB_FUNCTION ssize_t ROKEN_LIB_CALL
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| hex_decode(const char *str, void *data, size_t len)
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| {
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|     size_t l;
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|     unsigned char *p = data;
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|     size_t i;
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| 
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|     l = strlen(str);
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| 
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|     /* check for overflow, same as (l+1)/2 but overflow safe */
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|     if ((l/2) + (l&1) > len)
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| 	return -1;
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| 
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|     if (l & 1) {
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| 	p[0] = pos(str[0]);
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| 	str++;
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| 	p++;
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|     }
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|     for (i = 0; i < l / 2; i++)
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| 	p[i] = pos(str[i * 2]) << 4 | pos(str[(i * 2) + 1]);
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|     return i + (l & 1);
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| }
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