Experimental support for opportunitic use of jumbograms where only some hosts

on the local network support them.

This adds a new socket option, SO_JUMBO, and a new route flag,
RTF_JUMBO. If _both_ the socket option is set and the route for the host
has RTF_JUMBO set, ip_output will fragment the packet to the largest
possible size for the link, ignoring the card's MTU.

The semantics of this feature will be evolving rapidly; talk to us
if you intend to use it.

ok deraadt@ marius@

1 files changed, 24 insertions, 16 deletions

diff --git a/sbin/ping/ping.c b/sbin/ping/ping.c
index 75db06c5a37..9902f6902cd 100644
--- a/sbin/ping/ping.c
+++ b/sbin/ping/ping.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ping.c,v 1.70 2005/01/19 13:40:47 mpf Exp $	*/
+/*	$OpenBSD: ping.c,v 1.71 2005/05/27 04:55:27 mcbride Exp $	*/
 /*	$NetBSD: ping.c,v 1.20 1995/08/11 22:37:58 cgd Exp $	*/
 
 /*
@@ -43,7 +43,7 @@ static const char copyright[] =
 #if 0
 static char sccsid[] = "@(#)ping.c	8.1 (Berkeley) 6/5/93";
 #else
-static const char rcsid[] = "$OpenBSD: ping.c,v 1.70 2005/01/19 13:40:47 mpf Exp $";
+static const char rcsid[] = "$OpenBSD: ping.c,v 1.71 2005/05/27 04:55:27 mcbride Exp $";
 #endif
 #endif /* not lint */
 
@@ -107,18 +107,19 @@ struct tvi {
 
 /* various options */
 int options;
-#define	F_FLOOD		0x001
-#define	F_INTERVAL	0x002
-#define	F_NUMERIC	0x004
-#define	F_PINGFILLED	0x008
-#define	F_QUIET		0x010
-#define	F_RROUTE	0x020
-#define	F_SO_DEBUG	0x040
-#define	F_SO_DONTROUTE	0x080
-#define	F_VERBOSE	0x100
-#define	F_SADDR		0x200
-#define	F_HDRINCL	0x400
-#define	F_TTL		0x800
+#define	F_FLOOD		0x0001
+#define	F_INTERVAL	0x0002
+#define	F_NUMERIC	0x0004
+#define	F_PINGFILLED	0x0008
+#define	F_QUIET		0x0010
+#define	F_RROUTE	0x0020
+#define	F_SO_DEBUG	0x0040
+#define	F_SO_DONTROUTE	0x0080
+#define	F_VERBOSE	0x0100
+#define	F_SADDR		0x0200
+#define	F_HDRINCL	0x0400
+#define	F_TTL		0x0800
+#define	F_SO_JUMBO	0x1000
 
 /* multicast options */
 int moptions;
@@ -210,7 +211,8 @@ main(int argc, char *argv[])
 
 	preload = 0;
 	datap = &outpack[8 + sizeof(struct tvi)];
-	while ((ch = getopt(argc, argv, "DI:LRS:c:dfi:l:np:qrs:T:t:vw:")) != -1)
+	while ((ch = getopt(argc, argv,
+	    "DI:LRS:c:dfi:jl:np:qrs:T:t:vw:")) != -1)
 		switch(ch) {
 		case 'c':
 			npackets = strtonum(optarg, 1, INT_MAX, &errstr);
@@ -258,6 +260,9 @@ main(int argc, char *argv[])
 
 			options |= F_INTERVAL;
 			break;
+		case 'j':
+			options |= F_SO_JUMBO;
+			break;
 		case 'L':
 			moptions |= MULTICAST_NOLOOP;
 			loop = 0;
@@ -380,6 +385,9 @@ main(int argc, char *argv[])
 	if (options & F_SO_DONTROUTE)
 		(void)setsockopt(s, SOL_SOCKET, SO_DONTROUTE, (char *)&hold,
 		    sizeof(hold));
+	if (options & F_SO_JUMBO)
+		(void)setsockopt(s, SOL_SOCKET, SO_JUMBO, (char *)&hold,
+		    sizeof(hold));
 
 	if (options & F_TTL) {
 		if (IN_MULTICAST(ntohl(to->sin_addr.s_addr)))
@@ -1336,7 +1344,7 @@ void
 usage(void)
 {
 	(void)fprintf(stderr,
-	    "usage: ping [-DdfLnqRrv] [-c count] [-I ifaddr] [-i wait]\n"
+	    "usage: ping [-DdfjLnqRrv] [-c count] [-I ifaddr] [-i wait]\n"
 	    "\t[-l preload] [-p pattern] [-s packetsize] [-T tos] [-t ttl]\n"
 	    "\t[-w maxwait] host\n");
 	exit(1);