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/*-
* Copyright (c) 2021 Ribose Inc.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT HOLDERS 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 <cstdio>
#include <cstring>
#include "mem.h"
#include "logging.h"
#include <openssl/crypto.h>
void
secure_clear(void *vp, size_t size)
{
OPENSSL_cleanse(vp, size);
}
namespace rnp {
bool
hex_encode(const uint8_t *buf, size_t buf_len, char *hex, size_t hex_len, hex_format_t format)
{
if (hex_len < (buf_len * 2 + 1)) {
return false;
}
static const char *hex_low = "0123456789abcdef";
static const char *hex_up = "0123456789ABCDEF";
const char * hex_ch = (format == HEX_LOWERCASE) ? hex_low : hex_up;
hex[buf_len * 2] = '\0';
for (size_t i = 0; i < buf_len; i++) {
hex[i << 1] = hex_ch[buf[i] >> 4];
hex[(i << 1) + 1] = hex_ch[buf[i] & 0xF];
}
return true;
}
static bool
hex_char_decode(const char hex, uint8_t &res)
{
if ((hex >= '0') && (hex <= '9')) {
res = hex - '0';
return true;
}
if (hex >= 'a' && hex <= 'f') {
res = hex + 10 - 'a';
return true;
}
if (hex >= 'A' && hex <= 'F') {
res = hex + 10 - 'A';
return true;
}
return false;
}
size_t
hex_decode(const char *hex, uint8_t *buf, size_t buf_len)
{
size_t hexlen = strlen(hex);
/* check for 0x prefix */
if ((hexlen >= 2) && (hex[0] == '0') && ((hex[1] == 'x') || (hex[1] == 'X'))) {
hex += 2;
hexlen -= 2;
}
const char *end = hex + hexlen;
uint8_t * buf_st = buf;
uint8_t * buf_en = buf + buf_len;
while (hex < end) {
/* skip whitespaces */
if ((*hex < '0') &&
((*hex == ' ') || (*hex == '\t') || (*hex == '\r') || (*hex == '\n'))) {
hex++;
continue;
}
if (hexlen < 2) {
RNP_LOG("Invalid hex string length.");
return 0;
}
uint8_t lo, hi;
if (!hex_char_decode(*hex++, hi) || !hex_char_decode(*hex++, lo)) {
RNP_LOG("Hex decode failed on string: %s", hex);
return 0;
}
if (buf == buf_en) {
return 0;
}
*buf++ = (hi << 4) | lo;
}
return buf - buf_st;
}
} // namespace rnp