busybox

/*-

 * Copyright (c) 1990, 1993

 *      The Regents of the University of California.  All rights reserved.

 *

 * This code is derived from software contributed to Berkeley by

 * Van Jacobson.

 *

 * Special for busybox ported by Vladimir Oleynik <dzo@simtreas.ru> 2001

 * 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. All advertising materials mentioning features or use of this software

 *    must display the following acknowledgement:

 *      This product includes software developed by the University of

 *      California, Berkeley and its contributors.

 * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.

 */

​

/*

 * traceroute host  - trace the route ip packets follow going to "host".

 * Notes

 * -----

 * This program must be run by root or be setuid.  (I suggest that

 * you *don't* make it setuid -- casual use could result in a lot

 * of unnecessary traffic on our poor, congested nets.)

 *

 * I stole the idea for this program from Steve Deering.  Since

 * the first release, I've learned that had I attended the right

 * IETF working group meetings, I also could have stolen it from Guy

 * Almes or Matt Mathis.  I don't know (or care) who came up with

 * the idea first.  I envy the originators' perspicacity and I'm

 * glad they didn't keep the idea a secret.

 *

 * Tim Seaver, Ken Adelman and C. Philip Wood provided bug fixes and/or

 * enhancements to the original distribution.

 *

 * I've hacked up a round-trip-route version of this that works by

 * sending a loose-source-routed udp datagram through the destination

 * back to yourself.  Unfortunately, SO many gateways botch source

 * routing, the thing is almost worthless.  Maybe one day...

 *

 *  -- Van Jacobson (van@helios.ee.lbl.gov)

 *     Tue Dec 20 03:50:13 PST 1988

 */