mirror of
https://github.com/cryb-to/cryb-otp.git
synced 2024-12-22 20:31:07 +00:00
76 lines
2.5 KiB
C
76 lines
2.5 KiB
C
|
/*-
|
||
|
|
* Copyright (c) 2013-2018 The University of Oslo
|
||
|
|
* Copyright (c) 2016-2018 Dag-Erling Smørgrav
|
||
|
|
* 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. The name of the author may not be used to endorse or promote
|
||
|
|
* products derived from this software without specific prior written
|
||
|
|
* permission.
|
||
|
|
*
|
||
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 "cryb/impl.h"
|
||
|
|
|
||
|
|
#include <stddef.h>
|
||
|
|
#include <stdint.h>
|
||
|
|
|
||
|
|
#include <cryb/assert.h>
|
||
|
|
#include <cryb/oath.h>
|
||
|
|
#include <cryb/otp.h>
|
||
|
|
|
||
|
|
#include "cryb_otp_impl.h"
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Check whether a given response is correct for the given keyfile.
|
||
|
|
*/
|
||
|
|
int
|
||
|
|
otp_verify(oath_key *key, unsigned long response)
|
||
|
|
{
|
||
|
|
uint64_t prev;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
switch (key->mode) {
|
||
|
|
case om_hotp:
|
||
|
|
prev = key->counter;
|
||
|
|
ret = oath_hotp_match(key, response, HOTP_WINDOW);
|
||
|
|
assertf(key->counter >= prev, "counter went backwads");
|
||
|
|
if (ret > 0) {
|
||
|
|
assertf(key->counter > prev, "counter did not advance");
|
||
|
|
ret = key->counter - prev - 1;
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
case om_totp:
|
||
|
|
prev = key->lastused;
|
||
|
|
ret = oath_totp_match(key, response, TOTP_WINDOW);
|
||
|
|
assertf(key->lastused >= prev, "lastused went backwards");
|
||
|
|
if (ret > 0) {
|
||
|
|
assertf(key->lastused > prev, "lastused did not advance");
|
||
|
|
ret = key->lastused - prev / key->timestep;
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
default:
|
||
|
|
ret = -1;
|
||
|
|
}
|
||
|
|
/* oath_*_ret() return -1 on error, 0 on failure, 1 on success */
|
||
|
|
return (ret);
|
||
|
|
}
|