/*      $OpenBSD: mopd.c,v 1.19 2015/02/09 23:00:14 deraadt Exp $ */

/*
 * Copyright (c) 1993-96 Mats O Jansson.  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.
 */

/*
 * mopd - MOP Dump/Load Daemon
 *
 * Usage:       mopd [-3 | -4] [-adfv] interface
 */

#include "os.h"
#include "common/common.h"
#include "common/mopdef.h"
#include "common/device.h"
#include "common/print.h"
#include "common/pf.h"
#include "common/cmp.h"
#include "common/get.h"
#include "common/dl.h"
#include "common/rc.h"
#include "process.h"

#include "pwd.h"

/*
 * The list of all interfaces that are being listened to. 
 * "selects" on the descriptors in this list.
 */
struct if_info  *iflist;

void            Usage(void);
void            mopProcess(struct if_info *, u_char *);

int      AllFlag = 0;           /* listen on "all" interfaces */
int      DebugFlag = 0;         /* print debugging messages   */
int      ForegroundFlag = 0;    /* run in foreground          */
int      VersionFlag = 0;       /* print version              */
int      Not3Flag = 0;          /* Not MOP V3 messages.       */
int      Not4Flag = 0;          /* Not MOP V4 messages.       */
int      promisc = 1;           /* Need promisc mode    */

extern char *__progname;

int
main(int argc, char *argv[])
{
        int              c;
        char            *interface;
        struct passwd   *pw;

        extern char version[];

        while ((c = getopt(argc, argv, "34adfv")) != -1)
                switch (c) {
                case '3':
                        Not3Flag = 1;
                        break;
                case '4':
                        Not4Flag = 1;
                        break;
                case 'a':
                        AllFlag = 1;
                        break;
                case 'd':
                        DebugFlag++;
                        break;
                case 'f':
                        ForegroundFlag = 1;
                        break;
                case 'v':
                        VersionFlag = 1;
                        break;
                default:
                        Usage();
                        /* NOTREACHED */
                }

        if (VersionFlag) {
                fprintf(stdout,"%s: version %s\n", __progname, version);
                exit(0);
        }

        interface = argv[optind++];

        if ((AllFlag && interface) || (!AllFlag && interface == 0) ||
            (argc > optind) || (Not3Flag && Not4Flag))
                Usage();

        /* All error reporting is done through syslogs. */
        openlog(__progname, LOG_PID | LOG_CONS, LOG_DAEMON);
        tzset();

        if ((pw = getpwnam("_mopd")) == NULL)
                err(1, "getpwnam");

        if ((!ForegroundFlag) && DebugFlag)
                fprintf(stdout, "%s: not running as daemon, -d given.\n",
                    __progname);

        if ((!ForegroundFlag) && (!DebugFlag))
                if (daemon(0, 0) == -1)
                        err(1, NULL);

        syslog(LOG_INFO, "%s %s started.", __progname, version);

        if (AllFlag)
                deviceInitAll();
        else
                deviceInitOne(interface);

        if (chroot(MOP_FILE_PATH) == -1) {
                syslog(LOG_CRIT, "chroot %s: %m", MOP_FILE_PATH);
                exit(1);
        }
        if (chdir("/") == -1) {
                syslog(LOG_CRIT, "chdir(\"/\"): %m");
                exit(1);
        }
        if (setgroups(1, &pw->pw_gid) ||
            setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
            setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid)) {
                syslog(LOG_CRIT, "can't drop privileges: %m");
                exit(1);
        }
        endpwent();

        Loop();
        /* NOTREACHED */
}

void
Usage()
{
        fprintf(stderr, "usage: %s [-3 | -4] [-adfv] interface\n",
            __progname);
        exit(1);
}

/*
 * Process incoming packages.
 */
void
mopProcess(struct if_info *ii, u_char *pkt)
{
        u_char  *dst, *src;
        u_short  ptype;
        int      idx, trans, len;

        /* We don't known with transport, Guess! */
        trans = mopGetTrans(pkt, 0);

        /* Ok, return if we don't wan't this message */
        if ((trans == TRANS_ETHER) && Not3Flag) return;
        if ((trans == TRANS_8023) && Not4Flag)  return;

        idx = 0;
        mopGetHeader(pkt, &idx, &dst, &src, &ptype, &len, trans);

        /*
         * Ignore our own transmissions
         *
         */     
        if (mopCmpEAddr(ii->eaddr,src) == 0)
                return;

        switch (ptype) {
        case MOP_K_PROTO_DL:
                mopProcessDL(stdout, ii, pkt, &idx, dst, src, trans, len);
                break;
        case MOP_K_PROTO_RC:
                mopProcessRC(stdout, ii, pkt, &idx, dst, src, trans, len);
                break;
        default:
                break;
        }
}