/*
* Off-the-Record Messaging Toolkit
* Copyright (C) 2004-2012 Ian Goldberg, Chris Alexander, Nikita Borisov
* <otr@cypherpunks.ca>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* 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
*/
/* system headers */
#include <stdio.h>
#include <stdlib.h>
/* toolkit headers */
#include "parse.h"
#include "sesskeys.h"
static void usage(const char *progname)
{
fprintf(stderr, "Usage: %s aeskey\n"
"Calculate and display the MAC key derived from a given AES key.\n",
progname);
exit(1);
}
int main(int argc, char **argv)
{
unsigned char *argbuf;
size_t argbuflen;
unsigned char mackey[20];
if (argc != 2) {
usage(argv[0]);
}
argv_to_buf(&argbuf, &argbuflen, argv[1]);
/* AES keys are 128 bits long, so check for that */
if (!argbuf) {
usage(argv[0]);
}
if (argbuflen != 16) {
fprintf(stderr, "The AES key must be 32 hex chars long.\n");
usage(argv[0]);
}
sesskeys_make_mac(mackey, argbuf);
dump_data(stdout, "AES key", argbuf, 16);
dump_data(stdout, "MAC key", mackey, 20);
free(argbuf);
fflush(stdout);
return 0;
}