Add support for NFS mounts to be from non-reserved ports:

- new sysctl vfs.nfs.privport to require NFS mount requests to be on
reserved ports when set to 1 (the default).
- mountd now automatically sets the sysctl depending on the -n flag.
- add mountd_flags to rc.conf to enable the -n flag at boot.
deraadt@ ok

src/etc/rc

@@ -1,4 +1,4 @@
-#	$OpenBSD: rc,v 1.281 2006/03/27 16:53:10 reyk Exp $
+#	$OpenBSD: rc,v 1.282 2006/05/28 23:29:32 avsm Exp $
 
 # System startup script run by init on autoboot
 # or after single-user.
@@ -383,7 +383,7 @@ if [ X"${nfs_server}" = X"YES" -a -s /etc/exports -a \
     `sed -e '/^#/d' < /etc/exports | wc -l` -ne 0 ]; then
 	rm -f /var/db/mountdtab
 	echo -n > /var/db/mountdtab
-	echo -n ' mountd';		mountd
+	echo -n ' mountd';		mountd ${mountd_flags}
 	echo -n ' nfsd';		nfsd ${nfsd_flags}
 	if [ X"${lockd}" = X"YES" ]; then
 		echo -n ' rpc.lockd';	rpc.lockd

src/etc/rc.conf

@@ -1,6 +1,6 @@
 #!/bin/sh -
 #
-#	$OpenBSD: rc.conf,v 1.111 2006/03/27 16:53:10 reyk Exp $
+#	$OpenBSD: rc.conf,v 1.112 2006/05/28 23:29:32 avsm Exp $
 
 # set these to "NO" to turn them off.  otherwise, they're used as flags
 routed_flags=NO		# for normal use: "-q"
@@ -82,6 +82,7 @@ savecore_flags=			# "-z" to compress
 ypserv_flags=			# E.g. -1 for YP v1, -d for DNS etc
 yppasswdd_flags=NO		# "-d /etc/yp" if passwd files are in /etc/yp
 nfsd_flags="-tun 4"		# Crank the 4 for a busy NFS fileserver
+mountd_flags=			# "-n" to permit non-reserved port NFS mounts
 amd_dir=/tmp_mnt		# AMD's mount directory
 amd_master=/etc/amd/master	# AMD 'master' map
 syslogd_flags=			# add more flags, ie. "-u -a /chroot/dev/log"