/*      $NetBSD: btpand.c,v 1.1 2008/08/17 13:20:57 plunky Exp $        */

/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2008 Iain Hibbert
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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 <sys/wait.h>

#define L2CAP_SOCKET_CHECKED
#include <bluetooth.h>
#include <err.h>
#include <fcntl.h>
#include <paths.h>
#include <sdp.h>
#include <stdio.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "btpand.h"

/* global variables */
const char *    control_path;           /* -c <path> */
const char *    interface_name;         /* -i <ifname> */
const char *    service_name;           /* -s <service> */
uint16_t        service_class;

bdaddr_t        local_bdaddr;           /* -d <addr> */
bdaddr_t        remote_bdaddr;          /* -a <addr> */
uint16_t        l2cap_psm;              /* -p <psm> */
int             l2cap_mode;             /* -m <mode> */

int             server_limit;           /* -n <limit> */

static const struct {
        const char *    name;
        uint16_t        class;
        const char *    desc;
} services[] = {
        { "PANU", SDP_SERVICE_CLASS_PANU, "Personal Area Networking User" },
        { "NAP",  SDP_SERVICE_CLASS_NAP,  "Network Access Point"                  },
        { "GN",   SDP_SERVICE_CLASS_GN,   "Group Network"                 },
};

static void main_exit(int) __dead2;
static void main_detach(void);
static void usage(void) __dead2;

int
main(int argc, char *argv[])
{
        unsigned long   ul;
        char *          ep;
        int             ch, status;

        while ((ch = getopt(argc, argv, "a:c:d:i:l:m:p:S:s:")) != -1) {
                switch (ch) {
                case 'a': /* remote address */
                        if (!bt_aton(optarg, &remote_bdaddr)) {
                                struct hostent  *he;

                                if ((he = bt_gethostbyname(optarg)) == NULL)
                                        errx(EXIT_FAILURE, "%s: %s",
                                            optarg, hstrerror(h_errno));

                                bdaddr_copy(&remote_bdaddr,
                                        (bdaddr_t *)he->h_addr);
                        }

                        break;

                case 'c': /* control socket path */
                        control_path = optarg;
                        break;

                case 'd': /* local address */
                        if (!bt_devaddr(optarg, &local_bdaddr)) {
                                struct hostent  *he;

                                if ((he = bt_gethostbyname(optarg)) == NULL)
                                        errx(EXIT_FAILURE, "%s: %s",
                                            optarg, hstrerror(h_errno));

                                bdaddr_copy(&local_bdaddr,
                                        (bdaddr_t *)he->h_addr);
                        }
                        break;

                case 'i': /* tap interface name */
                        if (strchr(optarg, '/') == NULL) {
                                asprintf(&ep, "/dev/%s", optarg);
                                interface_name = ep;
                        } else
                                interface_name = optarg;
                        break;

                case 'l': /* limit server sessions */
                        ul = strtoul(optarg, &ep, 10);
                        if (*optarg == '\0' || *ep != '\0' || ul == 0)
                                errx(EXIT_FAILURE, "%s: invalid session limit",
                                        optarg);

                        server_limit = ul;
                        break;

                case 'm': /* link mode */
                        warnx("Setting link mode is not yet supported");
                        break;

                case 'p': /* protocol/service multiplexer */
                        ul = strtoul(optarg, &ep, 0);
                        if (*optarg == '\0' || *ep != '\0'
                            || ul > 0xffff || L2CAP_PSM_INVALID(ul))
                                errx(EXIT_FAILURE, "%s: invalid PSM", optarg);

                        l2cap_psm = ul;
                        break;

                case 's': /* service */
                case 'S': /* service (no SDP) */
                        for (ul = 0; ul < __arraycount(services); ul++) {
                                if (strcasecmp(optarg, services[ul].name) == 0)
                                        break;
                        }

                        if (ul == __arraycount(services))
                                errx(EXIT_FAILURE, "%s: unknown service", optarg);

                        if (ch == 's')
                                service_name = services[ul].name;

                        service_class = services[ul].class;
                        break;

                default:
                        usage();
                        /* NOTREACHED */
                }
        }

        argc -= optind;
        argv += optind;

        /* validate options */
        if (bdaddr_any(&local_bdaddr) || service_class == 0)
                usage();

        if (!bdaddr_any(&remote_bdaddr) && (server_limit != 0 ||
            control_path != NULL || (service_name != NULL && l2cap_psm != 0)))
                usage();

        /* default options */
        if (interface_name == NULL)
                interface_name = "/dev/tap";

        if (l2cap_psm == 0)
                l2cap_psm = L2CAP_PSM_BNEP;

        if (bdaddr_any(&remote_bdaddr) && server_limit == 0) {
                if (service_class == SDP_SERVICE_CLASS_PANU)
                        server_limit = 1;
                else
                        server_limit = 7;
        }

#ifdef L2CAP_LM_MASTER
        if (server_limit > 1 && service_class != SDP_SERVICE_CLASS_PANU)
                l2cap_mode |= L2CAP_LM_MASTER;
#endif

        /*
         * fork() now so that the setup can be done in the child process
         * (as kqueue is not inherited) but block in the parent until the
         * setup is finished so we can return an error if necessary.
         */
        switch(fork()) {
        case -1: /* bad */
                err(EXIT_FAILURE, "fork() failed");

        case 0: /* child */
                signal(SIGPIPE, SIG_IGN);

                openlog(getprogname(), LOG_NDELAY | LOG_PERROR | LOG_PID, LOG_DAEMON);

                channel_init();
                server_init();
                event_init();
                client_init();
                tap_init();

                main_detach();

                event_dispatch();
                break;

        default: /* parent */
                signal(SIGUSR1, main_exit);
                wait(&status);

                if (WIFEXITED(status))
                        exit(WEXITSTATUS(status));

                break;
        }

        err(EXIT_FAILURE, "exiting");
}

static void
main_exit(int s)
{

        /* child is all grown up */
        _exit(EXIT_SUCCESS);
}

static void
main_detach(void)
{
        int fd;

        if (kill(getppid(), SIGUSR1) == -1)
                log_err("Could not signal main process: %m");

        if (setsid() == -1)
                log_err("setsid() failed");

        fd = open(_PATH_DEVNULL, O_RDWR, 0);
        if (fd == -1) {
                log_err("Could not open %s", _PATH_DEVNULL);
        } else {
                (void)dup2(fd, STDIN_FILENO);
                (void)dup2(fd, STDOUT_FILENO);
                (void)dup2(fd, STDERR_FILENO);
                close(fd);
        }
}

static void
usage(void)
{
        const char *p = getprogname();
        int n = strlen(p);

        fprintf(stderr,
            "usage: %s [-i ifname] [-m mode] -a address -d device\n"
            "       %*s {-s service | -S service [-p psm]}\n"
            "       %s [-c path] [-i ifname] [-l limit] [-m mode] [-p psm] -d device\n"
            "       %*s {-s service | -S service}\n"
            "\n"
            "Where:\n"
            "\t-a address  remote bluetooth device\n"
            "\t-c path     SDP server socket\n"
            "\t-d device   local bluetooth device\n"
            "\t-i ifname   tap interface\n"
            "\t-l limit    limit server sessions\n"
            "\t-m mode     L2CAP link mode (NOT YET SUPPORTED)\n"
            "\t-p psm      L2CAP PSM\n"
            "\t-S service  service name (no SDP)\n"
            "\t-s service  service name\n"
            "\n"
            "Known services:\n"
            "", p, n, "", p, n, "");

        for (n = 0; n < __arraycount(services); n++)
                fprintf(stderr, "\t%s\t%s\n", services[n].name, services[n].desc);

        exit(EXIT_FAILURE);
}