Make route flush more powerful by allowing -iface/-interface or -priority

to be specified. So only routes matching these conditions will be flushed.
This will help making dhclient less dumb when fiddeling with routes.
OK henning@

2 files changed, 35 insertions, 7 deletions

diff --git a/sbin/route/route.8 b/sbin/route/route.8
index 7c9aa20c3f8..8849c509cb2 100644
--- a/sbin/route/route.8
+++ b/sbin/route/route.8
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: route.8,v 1.56 2008/05/07 06:29:48 claudio Exp $
+.\"	$OpenBSD: route.8,v 1.57 2009/05/30 19:50:28 claudio Exp $
 .\"	$NetBSD: route.8,v 1.6 1995/03/18 15:00:13 cgd Exp $
 .\"
 .\" Copyright (c) 1983, 1991, 1993
@@ -30,7 +30,7 @@
 .\"
 .\"	@(#)route.8	8.3 (Berkeley) 3/19/94
 .\"
-.Dd $Mdocdate: May 7 2008 $
+.Dd $Mdocdate: May 30 2009 $
 .Dt ROUTE 8
 .Os
 .Sh NAME
@@ -134,7 +134,7 @@ command has the syntax:
 .Bd -filled -offset indent
 .Nm route Op Fl dnqtv
 .Cm flush
-.Op Ar family
+.Op Ar modifiers
 .Ed
 .Pp
 If the
@@ -149,6 +149,12 @@ When the address family is specified by any one of the
 modifiers (listed below), only routes having destinations with addresses
 in the
 delineated family will be deleted.
+Also, only routes matching a specific interface or priority can be flushed
+by using the
+.Fl iface
+or
+.Fl priority
+modifiers.
 .Pp
 The
 .Cm monitor
diff --git a/sbin/route/route.c b/sbin/route/route.c
index 0c267553a69..3bdc528e6d8 100644
--- a/sbin/route/route.c
+++ b/sbin/route/route.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: route.c,v 1.128 2009/04/28 12:09:35 michele Exp $	*/
+/*	$OpenBSD: route.c,v 1.129 2009/05/30 19:50:28 claudio Exp $	*/
 /*	$NetBSD: route.c,v 1.16 1996/04/15 18:27:05 cgd Exp $	*/
 
 /*
@@ -210,18 +210,20 @@ main(int argc, char **argv)
 void
 flushroutes(int argc, char **argv)
 {
+	const char *errstr;
 	size_t needed;
 	int mib[7], rlen, seqno;
 	char *buf = NULL, *next, *lim = NULL;
 	struct rt_msghdr *rtm;
 	struct sockaddr *sa;
+	u_short prio = 0;
+	unsigned int ifindex;
 
 	if (uid)
 		errx(1, "must be root to alter routing table");
 	shutdown(s, 0); /* Don't want to read back our messages */
-	if (argc > 1) {
-		argv++;
-		if (argc == 2 && **argv == '-')
+	while (--argc > 0) {
+		if (**(++argv) == '-')
 			switch (keyword(*argv + 1)) {
 			case K_INET:
 				af = AF_INET;
@@ -235,6 +237,22 @@ flushroutes(int argc, char **argv)
 			case K_MPLS:
 				af = AF_MPLS;
 				break;
+			case K_IFACE:
+			case K_INTERFACE:
+				if (!--argc)
+					usage(1+*argv);
+				ifindex = if_nametoindex(*++argv);
+				if (ifindex == 0)
+					errx(1, "no such interface %s", *argv);
+				break;
+			case K_PRIORITY:
+				if (!--argc)
+					usage(1+*argv);
+				prio = strtonum(*++argv, 0, RTP_MAX, &errstr);
+				if (errstr)
+					errx(1, "priority is %s: %s", errstr,
+					    *argv);
+				break;
 			default:
 				usage(*argv);
 				/* NOTREACHED */
@@ -278,6 +296,10 @@ flushroutes(int argc, char **argv)
 		sa = (struct sockaddr *)(next + rtm->rtm_hdrlen);
 		if (af && sa->sa_family != af)
 			continue;
+		if (ifindex && rtm->rtm_index != ifindex)
+			continue;
+		if (prio && rtm->rtm_priority != prio)
+			continue;
 		if (sa->sa_family == AF_KEY)
 			continue;  /* Don't flush SPD */
 		if (debugonly)