This patch provides support for 'ip tuntap', allowing creation and
deletion of persistent tun/tap devices.

The support for _listing_ devices relies on the patch I just sent to
netdev ([ref]), although
creation and deletion work without that patch.

diff --git a/ip/Makefile b/ip/Makefile
index 98ba876..e868f3e 100644
--- a/ip/Makefile
+++ b/ip/Makefile

@@ -1,6 +1,6 @@
 IPOBJ=ip.o ipaddress.o ipaddrlabel.o iproute.o iprule.o \
     rtm_map.o iptunnel.o ip6tunnel.o tunnel.o ipneigh.o ipntable.o iplink.o \
-    ipmaddr.o ipmonitor.o ipmroute.o ipprefix.o \
+    ipmaddr.o ipmonitor.o ipmroute.o ipprefix.o iptuntap.o \
     ipxfrm.o xfrm_state.o xfrm_policy.o xfrm_monitor.o \
     iplink_vlan.o link_veth.o link_gre.o
 

diff --git a/ip/ip.c b/ip/ip.c
index 2bd54b2..d846a76 100644
--- a/ip/ip.c
+++ b/ip/ip.c

@@ -47,7 +47,7 @@ static void usage(void)
 "Usage: ip [ OPTIONS ] OBJECT { COMMAND | help }\n"
 "       ip [ -force ] -batch filename\n"
 "where  OBJECT := { link | addr | addrlabel | route | rule | neigh | ntable |\n"
-"                   tunnel | maddr | mroute | monitor | xfrm }\n"
+"                   tunnel | tuntap | maddr | mroute | monitor | xfrm }\n"
 "       OPTIONS := { -V[ersion] | -s[tatistics] | -d[etails] | -r[esolve] |\n"
 "                    -f[amily] { inet | inet6 | ipx | dnet | link } |\n"
 "                    -o[neline] | -t[imestamp] | -b[atch] [filename] }\n");

@@ -75,6 +75,8 @@ static const struct cmd {
 	{ "link",	do_iplink },
 	{ "tunnel",	do_iptunnel },
 	{ "tunl",	do_iptunnel },
+	{ "tuntap",	do_iptuntap },
+	{ "tap",	do_iptuntap },
 	{ "monitor",	do_ipmonitor },
 	{ "xfrm",	do_xfrm },
 	{ "mroute",	do_multiroute },

diff --git a/ip/ip_common.h b/ip/ip_common.h
index 273065f..c857667 100644
--- a/ip/ip_common.h
+++ b/ip/ip_common.h

@@ -32,6 +32,7 @@ extern int do_ipneigh(int argc, char **argv);
 extern int do_ipntable(int argc, char **argv);
 extern int do_iptunnel(int argc, char **argv);
 extern int do_ip6tunnel(int argc, char **argv);
+extern int do_iptuntap(int argc, char **argv);
 extern int do_iplink(int argc, char **argv);
 extern int do_ipmonitor(int argc, char **argv);
 extern int do_multiaddr(int argc, char **argv);

diff --git a/ip/iptuntap.c b/ip/iptuntap.c
new file mode 100644
index 0000000..b480296
--- /dev/null
+++ b/ip/iptuntap.c

@@ -0,0 +1,322 @@
+/*
+ * iptunnel.c	       "ip tuntap"
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	David Woodhouse <David.Woodhouse@intel.com>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <sys/ioctl.h>
+#include <linux/if.h>
+#include <linux/if_tun.h>
+#include <pwd.h>
+#include <grp.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <errno.h>
+
+#include "rt_names.h"
+#include "utils.h"
+#include "ip_common.h"
+
+#define TUNDEV "/dev/net/tun"
+
+static void usage(void) __attribute__((noreturn));
+
+static void usage(void)
+{
+	fprintf(stderr, "Usage: ip tuntap { add | del } [ dev PHYS_DEV ] \n");
+	fprintf(stderr, "          [ mode { tun | tap } ] [ user USER ] [ group GROUP ]\n");
+	fprintf(stderr, "          [ one_queue ] [ no_pi ] [ vnet_hdr ]\n");
+	fprintf(stderr, "\n");
+	fprintf(stderr, "Where: USER  := { STRING | NUMBER }\n");
+	fprintf(stderr, "       GROUP := { STRING | NUMBER }\n");
+	exit(-1);
+}
+
+static int tap_add_ioctl(struct ifreq *ifr, uid_t uid, gid_t gid)
+{
+	int fd = open(TUNDEV, O_RDWR);
+	int ret = -1;
+
+#ifndef IFF_TUN_EXCL
+#define IFF_TUN_EXCL	0x8000
+#endif
+	ifr->ifr_flags |= IFF_TUN_EXCL;
+
+	if (fd < 0) {
+		perror("open");
+		return -1;
+	}
+	if (ioctl(fd, TUNSETIFF, ifr)) {
+		perror("ioctl(TUNSETIFF)");
+		goto out;
+	}
+	if (uid != -1 && ioctl(fd, TUNSETOWNER, uid)) {
+		perror("ioctl(TUNSETOWNER)");
+		goto out;
+	}
+	if (gid != -1 && ioctl(fd, TUNSETGROUP, gid)) {
+		perror("ioctl(TUNSETGROUP)");
+		goto out;
+	}
+	if (ioctl(fd, TUNSETPERSIST, 1)) {
+		perror("ioctl(TUNSETPERSIST)");
+		goto out;
+	}
+	ret = 0;
+ out:
+	close(fd);
+	return ret;
+}
+