Add a min TTL flag to go along with the max TTL flag. That is, this flag

allows you to start tracing at a hop number other than 1.

Submitted by:	Stefan `Sec` Zehl <sec@42.org>

2 files changed, 44 insertions, 20 deletions

diff --git a/contrib/traceroute/traceroute.8 b/contrib/traceroute/traceroute.8
index 26e11b6..16fba5c 100644
--- a/contrib/traceroute/traceroute.8
+++ b/contrib/traceroute/traceroute.8
@@ -13,14 +13,14 @@
 .\" IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 .\" WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 .\"
-.\"	$Header: /home/ncvs/src/contrib/traceroute/traceroute.8,v 1.3 1998/01/09 18:46:53 steve Exp $
+.\"	$Header: /home/ncvs/src/contrib/traceroute/traceroute.8,v 1.4 1999/05/06 03:23:23 archie Exp $
 .\"
 .TH TRACEROUTE 8 "27 September 1996"
 .UC 6
 .SH NAME
 traceroute \- print the route packets take to network host
 .SH SYNOPSIS
-.. while ((op = getopt(argc, argv, "dnrvg:m:p:q:s:t:w:")) != EOF)
+.. while ((op = getopt(argc, argv, "dnrvg:M:m:P:p:q:s:t:w:")) != EOF)
 .na
 .B traceroute
 [
@@ -29,35 +29,39 @@ traceroute \- print the route packets take to network host
 .B \-g
 .I gw_host
 ] [
-.B \-m
-max_ttl
-.I ]
+.B \-M
+.I min_ttl
+] 
 .br
 .ti +8
 [
+.B \-m
+.I max_ttl
+] [
 .B \-P
 .I proto
 ] [
 .B \-p
 .I port
-] [
-.B \-q
-.I nqueries
 ]
 .br
 .ti +8
 [
+.B \-q
+.I nqueries
+] [
 .B \-s
 .I src_addr
 ] [
 .B \-t
 .I tos
-] [
-.B \-w
-.I waittime
 ]
 .br
 .ti +8
+[
+.B \-w
+.I waittime
+]
 .I host
 [
 .I packetlen
@@ -86,6 +90,10 @@ Print a summary of how many probes were not answered for each hop.
 .B \-g
 Specify a loose source route gateway (8 maximum).
 .TP
+.B \-M
+Set the initial time-to-live value used in outgoing probe packets.
+The default is 1, i.e., start with the first hop.
+.TP
 .B \-m
 Set the max time-to-live (max number of hops) used in outgoing probe
 packets.  The default is 30 hops (the same default used for TCP
diff --git a/contrib/traceroute/traceroute.c b/contrib/traceroute/traceroute.c
index 2a6dd51..641577c 100644
--- a/contrib/traceroute/traceroute.c
+++ b/contrib/traceroute/traceroute.c
@@ -24,7 +24,7 @@ static const char copyright[] =
     "@(#) Copyright (c) 1988, 1989, 1991, 1994, 1995, 1996\n\
 The Regents of the University of California.  All rights reserved.\n";
 static const char rcsid[] =
-    "@(#)$Header: /home/ncvs/src/contrib/traceroute/traceroute.c,v 1.8 1999/02/16 14:19:50 des Exp $ (LBL)";
+    "@(#)$Header: /home/ncvs/src/contrib/traceroute/traceroute.c,v 1.9 1999/05/06 03:23:24 archie Exp $ (LBL)";
 #endif
 
 /*
@@ -298,6 +298,7 @@ char *source;
 char *hostname;
 
 int nprobes = 3;
+int min_ttl = 1;
 int max_ttl = 30;
 u_short ident;
 u_short port;			/* protocol specific base "port" */
@@ -412,7 +413,7 @@ main(int argc, char **argv)
 		prog = argv[0];
 
 	opterr = 0;
-	while ((op = getopt(argc, argv, "Sdnrvg:m:P:p:q:s:t:w:")) != EOF)
+	while ((op = getopt(argc, argv, "Sdnrvg:M:m:P:p:q:s:t:w:")) != EOF)
 		switch (op) {
 
 		case 'S':
@@ -433,11 +434,20 @@ main(int argc, char **argv)
 			++lsrr;
 			break;
 
+		case 'M':
+			min_ttl = atoi(optarg);
+			if (min_ttl < 1 || min_ttl > 0xff) {
+				Fprintf(stderr, "%s: invalid ttl value %s\n",
+				    prog, optarg);
+				exit(1);
+			}
+			break;
+
 		case 'm':
 			max_ttl = atoi(optarg);
-			if (max_ttl <= 1) {
-				Fprintf(stderr, "%s: max ttl must be > 1\n",
-				    prog);
+			if (max_ttl < 1 || max_ttl > 0xff) {
+				Fprintf(stderr, "%s: invalid ttl value %s\n",
+				    prog, optarg);
 				exit(1);
 			}
 			break;
@@ -532,6 +542,12 @@ main(int argc, char **argv)
 			usage();
 		}
 
+	/* Check min vs. max TTL */
+	if (min_ttl > max_ttl) {
+		Fprintf(stderr, "%s: min ttl must be <= max ttl\n", prog);
+		exit(1);
+	}
+
 	/* Process destination and optional packet size */
 	switch (argc - optind) {
 
@@ -705,7 +721,7 @@ main(int argc, char **argv)
 	Fprintf(stderr, ", %d hops max, %d byte packets\n", max_ttl, packlen);
 	(void)fflush(stderr);
 
-	for (ttl = 1; ttl <= max_ttl; ++ttl) {
+	for (ttl = min_ttl; ttl <= max_ttl; ++ttl) {
 		u_int32_t lastaddr = 0;
 		int got_there = 0;
 		int unreachable = 0;
@@ -1205,8 +1221,8 @@ usage(void)
 	extern char version[];
 
 	Fprintf(stderr, "Version %s\n", version);
-	Fprintf(stderr, "Usage: %s [-dnrv] [-w wait] [-m max_ttl] [-p port#] \
-[-q nqueries]\n\t [-t tos] [-s src_addr] [-g gateway] host [data_size]\n",
-	    prog);
+	Fprintf(stderr, "Usage: %s [-dnrv] [-w wait] [-m max_ttl] [-M min_ttl] \
+[-P proto]\n\t [-p port#] [-q nqueries] [-t tos] [-s src_addr] [-g gateway] \
+\n\t host [data_size]\n", prog);
 	exit(1);
 }