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Diffstat (limited to 'usr.sbin/traceroute/README')
| -rw-r--r-- | usr.sbin/traceroute/README | 133 |
1 files changed, 18 insertions, 115 deletions
diff --git a/usr.sbin/traceroute/README b/usr.sbin/traceroute/README index 6d33c6c..9d9f4e2 100644 --- a/usr.sbin/traceroute/README +++ b/usr.sbin/traceroute/README @@ -1,126 +1,29 @@ -Tue Dec 27 06:24:24 PST 1988 +@(#) $Header: README,v 1.6 95/08/27 16:58:04 leres Exp $ (LBL) + +TRACEROUTE 1.2 +Lawrence Berkeley National Laboratory +Network Research Group +traceroute@ee.lbl.gov +ftp://ftp.ee.lbl.gov/traceroute-*.tar.Z Traceroute is a system administrators utility to trace the route ip packets from the current system take in getting to some destination system. See the comments at the front of the program for a description of its use. -This program - - a) can only be run by root (it uses raw ip sockets). - - b) REQUIRES A KERNEL MOD to the raw ip output code to run. - -If you want to hack on your kernel, my modified version of the -routine rip_output (in file /sys/netinet/raw_ip.c) is attached. -This code may or may not resemble the code in your kernel. -It may offer you a place to start but I make no promises. -If you do hack your kernel, remember to test everything that uses -raw ip sockets (e.g., ping and egpup/gated) & make sure they still -work. I wish you the best of luck and you're on your own. - -If your system has the ttl bug mentioned in the source, you -might want to fix it while you're in the kernel. (This bug -appears in all releases of BSD up to but not including 4.3tahoe. -If your version of netinet/ip_icmp.c is any earlier than 7.3 -(April, '87), it has the bug.) The fix is just to add the line - ip->ip_ttl = MAXTTL; -after the line - ip->ip_src = t; -(or anywhere before the call to icmp_send) in routine icmp_reflect. - -If you're running this on a pre-4.3bsd system (e.g., Sun 3.x, -Ultrix) that strips ip headers from icmp messages, add -DARCHAIC -to CFLAGS in the Makefile. Also note that rip_output contains -a conditional for a 4.2/4.3 change in the location of a raw -socket's protocol number. I've checked this under 4.3 & Sun OS -3.5 but you should double-check your system to make sure the -appropriate branch of the #if is taken (check the line that -assigned to ip->ip_p in your system's original rip_output). +This program uses raw ip sockets and must be run as root (or installed +setuid to root). A couple of awk programs to massage the traceroute output are -included. "mean.awk" and "median.awk" compute the mean and median -time to each hop, respectively. I've found that something like - - traceroute -q 7 foo.somewhere >t - awk -f median.awk t | graph - -can give you a quick picture of the bad spots on a long -path (median is usually a better noise filter than mean). - -Enjoy. - - - Van Jacobson (van@helios.ee.lbl.gov) - --------------------- rip_output from /sys/netinet/raw_ip.c -rip_output(m, so) - register struct mbuf *m; - struct socket *so; -{ - register struct ip *ip; - int error; - struct rawcb *rp = sotorawcb(so); - struct sockaddr_in *sin; -#if BSD>=43 - short proto = rp->rcb_proto.sp_protocol; -#else - short proto = so->so_proto->pr_protocol; -#endif - /* - * if the protocol is IPPROTO_RAW, the user handed us a - * complete IP packet. Otherwise, allocate an mbuf for a - * header and fill it in as needed. - */ - if (proto != IPPROTO_RAW) { - /* - * Calculate data length and get an mbuf - * for IP header. - */ - int len = 0; - struct mbuf *m0; - - for (m0 = m; m; m = m->m_next) - len += m->m_len; - - m = m_get(M_DONTWAIT, MT_HEADER); - if (m == 0) { - m = m0; - error = ENOBUFS; - goto bad; - } - m->m_off = MMAXOFF - sizeof(struct ip); - m->m_len = sizeof(struct ip); - m->m_next = m0; - - ip = mtod(m, struct ip *); - ip->ip_tos = 0; - ip->ip_off = 0; - ip->ip_p = proto; - ip->ip_len = sizeof(struct ip) + len; - ip->ip_ttl = MAXTTL; - } else - ip = mtod(m, struct ip *); +included. "mean.awk" and "median.awk" compute the mean and median time +to each hop, respectively. I've found that something like - if (rp->rcb_flags & RAW_LADDR) { - sin = (struct sockaddr_in *)&rp->rcb_laddr; - if (sin->sin_family != AF_INET) { - error = EAFNOSUPPORT; - goto bad; - } - ip->ip_src.s_addr = sin->sin_addr.s_addr; - } else - ip->ip_src.s_addr = 0; + traceroute -q 7 foo.somewhere >t + awk -f median.awk t | graph - ip->ip_dst = ((struct sockaddr_in *)&rp->rcb_faddr)->sin_addr; +can give you a quick picture of the bad spots on a long path (median is +usually a better noise filter than mean). -#if BSD>=43 - return (ip_output(m, rp->rcb_options, &rp->rcb_route, - (so->so_options & SO_DONTROUTE) | IP_ALLOWBROADCAST)); -#else - return (ip_output(m, (struct mbuf *)0, &rp->rcb_route, - (so->so_options & SO_DONTROUTE) | IP_ALLOWBROADCAST)); -#endif -bad: - m_freem(m); - return (error); -} +Problems, bugs, questions, desirable enhancements, source code +contributions, etc., should be sent to the email address +"traceroute@ee.lbl.gov". |
