/*
 *  Hans - IP over ICMP
 *  Copyright (C) 2009 Friedrich Schöller <hans@schoeller.se>
 *  
 *  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 3 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, see <http://www.gnu.org/licenses/>.
 *  
 */

#include "auth.h"
#include "sha1.h"
#include "utility.h"

#include <arpa/inet.h>

Auth::Auth(const char *passphrase)
{
    this->passphrase = passphrase;
}

Auth::Response Auth::getResponse(const Challenge &challenge) const
{
    SHA1 hasher;

    Response response;

    hasher << passphrase.c_str();
    hasher.Input(&challenge[0], challenge.size());

    hasher.Result((unsigned int *)response.data);
    
    for (int i = 0; i < 5; i++)
        response.data[i] = htonl(response.data[i]);

    return response;
}

Auth::Challenge Auth::generateChallenge(int length) const
{
    Challenge challenge;
    challenge.resize(length);

    for (int i = 0; i < length; i++)
        challenge[i] = Utility::rand();

    return challenge;
}