/*
* Copyright (c) 2004-2005 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* 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 above 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. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE 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.
*/
#include <config.h>
#include "roken.h"
#include <ctype.h>
#include "hex.h"
static const char hexchar[16] = "0123456789ABCDEF";
static int
pos(char c)
{
const char *p;
c = toupper((unsigned char)c);
for (p = hexchar; *p; p++)
if (*p == c)
return p - hexchar;
return -1;
}
ROKEN_LIB_FUNCTION ssize_t ROKEN_LIB_CALL
hex_encode(const void *data, size_t size, char **str)
{
const unsigned char *q = data;
size_t i;
char *p;
/* check for overflow */
if (size * 2 < size) {
*str = NULL;
return -1;
}
p = malloc(size * 2 + 1);
if (p == NULL) {
*str = NULL;
return -1;
}
for (i = 0; i < size; i++) {
p[i * 2] = hexchar[(*q >> 4) & 0xf];
p[i * 2 + 1] = hexchar[*q & 0xf];
q++;
}
p[i * 2] = '\0';
*str = p;
return i * 2;
}
ROKEN_LIB_FUNCTION ssize_t ROKEN_LIB_CALL
hex_decode(const char *str, void *data, size_t len)
{
size_t l;
unsigned char *p = data;
size_t i;
l = strlen(str);
/* check for overflow, same as (l+1)/2 but overflow safe */
if ((l/2) + (l&1) > len)
return -1;
if (l & 1) {
p[0] = pos(str[0]);
str++;
p++;
}
for (i = 0; i < l / 2; i++)
p[i] = pos(str[i * 2]) << 4 | pos(str[(i * 2) + 1]);
return i + (l & 1);
}