/*
 * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
 * 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. Neither the name of Hyra nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * 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 OWNER 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 <net/stpsession.h>
#include <libostp/session.h>
#include <crypto/aes.h>
#include <net/param.h>
#include <net/auth.h>
#include <otconfig.h>
#include <stdio.h>

static int
handle_pap(struct ostp_session *sp, const struct pap *pap, const unsigned char *session_key)
{
    int error = -1;
    uint8_t attempts = 0;
    struct pap tmp_pap = *pap;
    const size_t LEN = sizeof(struct pap);

    /* TODO: Support more SPW bits */
    while (1) {
        /* Quick session request, jump right in! */
        if (ISSET(tmp_pap.spw, PAP_SPW_QSR)) {
            printf("Got QSR, starting session...\n");
            send_frame(sp->sockfd, &tmp_pap, LEN, session_key);
            return 0;
        }

        /* We have exhausted our attempts */
        if (attempts >= ARBITRATION_MAX) {
            printf("Too many arbitration attempts, bailing!\n");
            return -1;
        }

        printf("Got bad SPW from client\n");
        printf("Attempting arbitration...\n");

        tmp_pap.spw = 0;
        tmp_pap.code = PAP_BAD_SPW;

        /* Send in PAP and wait for response */
        if ((error = send_frame(sp->sockfd, &tmp_pap, LEN, session_key)) < -1) {
            printf("Failed to send PAP frame\n");
            return -1;
        }
        if ((error = recv_frame(sp->sockfd, LEN, session_key, &tmp_pap)) < -1) {
            printf("Failed to recv PAP frame\n");
            return error;
        }

        ++attempts;
    }

    return 0;
}

int
negotiate_spw(struct ostp_session *sp, unsigned char *session_key)
{
    const size_t LEN = sizeof(struct pap);
    struct pap pap;
    int error;

    /* Get PAP from the network */
    if ((error = recv_frame(sp->sockfd, LEN, session_key, &pap)) < -1) {
        return error;
    }

    return handle_pap(sp, &pap, session_key);
}