tinc/src/utils.c
2011-07-03 23:33:56 +02:00

148 lines
3.9 KiB
C

/*
utils.c -- gathering of some stupid small functions
Copyright (C) 1999-2005 Ivo Timmermans
2000-2009 Guus Sliepen <guus@tinc-vpn.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "system.h"
#include "../src/logger.h"
#include "utils.h"
static const char hexadecimals[] = "0123456789ABCDEF";
static const char base64imals[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static int charhex2bin(char c) {
if(isdigit(c))
return c - '0';
else
return toupper(c) - 'A' + 10;
}
static int charb64decode(char c) {
if(c >= 'a')
return c - 'a' + 26;
else if(c >= 'A')
return c - 'A';
else if(c >= '0')
return c - '0' + 52;
else if(c == '+')
return 62;
else
return 63;
}
void hex2bin(char *src, char *dst, int length) {
int i;
for(i = 0; i < length; i++)
dst[i] = charhex2bin(src[i * 2]) * 16 + charhex2bin(src[i * 2 + 1]);
}
void bin2hex(char *src, char *dst, int length) {
int i;
for(i = length - 1; i >= 0; i--) {
dst[i * 2 + 1] = hexadecimals[(unsigned char) src[i] & 15];
dst[i * 2] = hexadecimals[(unsigned char) src[i] >> 4];
}
}
int b64decode(const char *src, char *dst, int length) {
uint32_t triplet = 0;
unsigned char *udst = dst;
for(int i = 0; i < length; i++) {
triplet |= charb64decode(src[i]) << (6 * (i & 3));
if((i & 3) == 3) {
udst[0] = triplet & 0xff; triplet >>= 8;
udst[1] = triplet & 0xff; triplet >>= 8;
udst[2] = triplet;
triplet = 0;
udst += 3;
}
}
if((length & 3) == 3) {
udst[0] = triplet & 0xff; triplet >>= 8;
udst[1] = triplet & 0xff;
return length / 4 * 3 + 2;
} else if((length & 3) == 2) {
udst[0] = triplet & 0xff;
return length / 4 * 3 + 1;
} else {
return length / 4 * 3;
}
}
int b64encode(const char *src, char *dst, int length) {
uint32_t triplet;
const unsigned char *usrc = src;
int origlen = length;
while(length > 0) {
if(length >= 3) {
triplet = usrc[0] | usrc[1] << 8 | usrc[2] << 16;
dst[0] = base64imals[triplet & 63]; triplet >>= 6;
dst[1] = base64imals[triplet & 63]; triplet >>= 6;
dst[2] = base64imals[triplet & 63]; triplet >>= 6;
dst[3] = base64imals[triplet];
dst += 4; usrc += 3; length -= 3;
} else if(length >=2) {
triplet = usrc[0] | usrc[1] << 8;
dst[0] = base64imals[triplet & 63]; triplet >>= 6;
dst[1] = base64imals[triplet & 63]; triplet >>= 6;
dst[2] = base64imals[triplet];
dst[3] = 0;
return origlen / 3 * 4 + 3;
} else {
triplet = usrc[0];
dst[0] = base64imals[triplet & 63]; triplet >>= 6;
dst[1] = base64imals[triplet];
dst[2] = 0;
return origlen / 3 * 4 + 2;
}
}
*dst = 0;
return origlen / 4 * 3;
}
#if defined(HAVE_MINGW) || defined(HAVE_CYGWIN)
#ifdef HAVE_CYGWIN
#include <w32api/windows.h>
#endif
const char *winerror(int err) {
static char buf[1024], *newline;
if (!FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, err, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf, sizeof(buf), NULL)) {
strncpy(buf, "(unable to format errormessage)", sizeof(buf));
};
if((newline = strchr(buf, '\r')))
*newline = '\0';
return buf;
}
#endif
unsigned int bitfield_to_int(const void *bitfield, size_t size) {
unsigned int value = 0;
if(size > sizeof value)
size = sizeof value;
memcpy(&value, bitfield, size);
return value;
}