--- /dev/null
+/*
+ * Universal TUN/TAP device driver.
+ * Copyright (C) 1999-2000 Maxim Krasnyansky <max_mk@yahoo.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __IF_TUN_H
+#define __IF_TUN_H
+
+#include <linux/types.h>
+#include <linux/if_ether.h>
+
+/* Read queue size */
+#define TUN_READQ_SIZE 500
+
+/* TUN device flags */
+#define TUN_TUN_DEV 0x0001
+#define TUN_TAP_DEV 0x0002
+#define TUN_TYPE_MASK 0x000f
+
+#define TUN_FASYNC 0x0010
+#define TUN_NOCHECKSUM 0x0020
+#define TUN_NO_PI 0x0040
+#define TUN_ONE_QUEUE 0x0080
+#define TUN_PERSIST 0x0100
+#define TUN_VNET_HDR 0x0200
+
+/* Ioctl defines */
+#define TUNSETNOCSUM _IOW('T', 200, int)
+#define TUNSETDEBUG _IOW('T', 201, int)
+#define TUNSETIFF _IOW('T', 202, int)
+#define TUNSETPERSIST _IOW('T', 203, int)
+#define TUNSETOWNER _IOW('T', 204, int)
+#define TUNSETLINK _IOW('T', 205, int)
+#define TUNSETGROUP _IOW('T', 206, int)
+#define TUNGETFEATURES _IOR('T', 207, unsigned int)
+#define TUNSETOFFLOAD _IOW('T', 208, unsigned int)
+#define TUNSETTXFILTER _IOW('T', 209, unsigned int)
+#define TUNGETIFF _IOR('T', 210, unsigned int)
+#define TUNGETSNDBUF _IOR('T', 211, int)
+#define TUNSETSNDBUF _IOW('T', 212, int)
+
+/* TUNSETIFF ifr flags */
+#define IFF_TUN 0x0001
+#define IFF_TAP 0x0002
+#define IFF_NO_PI 0x1000
+#define IFF_ONE_QUEUE 0x2000
+#define IFF_VNET_HDR 0x4000
+
+/* Features for GSO (TUNSETOFFLOAD). */
+#define TUN_F_CSUM 0x01 /* You can hand me unchecksummed packets. */
+#define TUN_F_TSO4 0x02 /* I can handle TSO for IPv4 packets */
+#define TUN_F_TSO6 0x04 /* I can handle TSO for IPv6 packets */
+#define TUN_F_TSO_ECN 0x08 /* I can handle TSO with ECN bits. */
+
+/* Protocol info prepended to the packets (when IFF_NO_PI is not set) */
+#define TUN_PKT_STRIP 0x0001
+struct tun_pi {
+ __u16 flags;
+ __be16 proto;
+};
+
+/*
+ * Filter spec (used for SETXXFILTER ioctls)
+ * This stuff is applicable only to the TAP (Ethernet) devices.
+ * If the count is zero the filter is disabled and the driver accepts
+ * all packets (promisc mode).
+ * If the filter is enabled in order to accept broadcast packets
+ * broadcast addr must be explicitly included in the addr list.
+ */
+#define TUN_FLT_ALLMULTI 0x0001 /* Accept all multicast packets */
+struct tun_filter {
+ __u16 flags; /* TUN_FLT_ flags see above */
+ __u16 count; /* Number of addresses */
+ __u8 addr[0][ETH_ALEN];
+};
+
+#endif /* __IF_TUN_H */
--- /dev/null
+/*
+ * 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 ] [ 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;
+
+#ifdef IFF_TUN_EXCL
+ ifr->ifr_flags |= IFF_TUN_EXCL;
+#endif
+
+ fd = open(TUNDEV, O_RDWR);
+ 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;
+}
+
+static int tap_del_ioctl(struct ifreq *ifr)
+{
+ int fd = open(TUNDEV, O_RDWR);
+ int ret = -1;
+
+ if (fd < 0) {
+ perror("open");
+ return -1;
+ }
+ if (ioctl(fd, TUNSETIFF, ifr)) {
+ perror("ioctl(TUNSETIFF)");
+ goto out;
+ }
+ if (ioctl(fd, TUNSETPERSIST, 0)) {
+ perror("ioctl(TUNSETPERSIST)");
+ goto out;
+ }
+ ret = 0;
+ out:
+ close(fd);
+ return ret;
+
+}
+static int parse_args(int argc, char **argv, struct ifreq *ifr, uid_t *uid, gid_t *gid)
+{
+ int count = 0;
+
+ memset(ifr, 0, sizeof(*ifr));
+
+ ifr->ifr_flags |= IFF_NO_PI;
+
+ while (argc > 0) {
+ if (matches(*argv, "mode") == 0) {
+ NEXT_ARG();
+ if (matches(*argv, "tun") == 0) {
+ if (ifr->ifr_flags & IFF_TAP) {
+ fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
+ exit(-1);
+ }
+ ifr->ifr_flags |= IFF_TUN;
+ } else if (matches(*argv, "tap") == 0) {
+ if (ifr->ifr_flags & IFF_TUN) {
+ fprintf(stderr,"You managed to ask for more than one tunnel mode.\n");
+ exit(-1);
+ }
+ ifr->ifr_flags |= IFF_TAP;
+ } else {
+ fprintf(stderr,"Cannot guess tunnel mode.\n");
+ exit(-1);
+ }
+ } else if (uid && matches(*argv, "user") == 0) {
+ char *end;
+ unsigned long user;
+
+ NEXT_ARG();
+ if (**argv && ((user = strtol(*argv, &end, 10)), !*end))
+ *uid = user;
+ else {
+ struct passwd *pw = getpwnam(*argv);
+ if (!pw) {
+ fprintf(stderr, "invalid user \"%s\"\n", *argv);
+ exit(-1);
+ }
+ *uid = pw->pw_uid;
+ }
+ } else if (gid && matches(*argv, "group") == 0) {
+ char *end;
+ unsigned long group;
+
+ NEXT_ARG();
+
+ if (**argv && ((group = strtol(*argv, &end, 10)), !*end))
+ *gid = group;
+ else {
+ struct group *gr = getgrnam(*argv);
+ if (!gr) {
+ fprintf(stderr, "invalid group \"%s\"\n", *argv);
+ exit(-1);
+ }
+ *gid = gr->gr_gid;
+ }
+ } else if (matches(*argv, "pi") == 0) {
+ ifr->ifr_flags &= ~IFF_NO_PI;
+ } else if (matches(*argv, "one_queue") == 0) {
+ ifr->ifr_flags |= IFF_ONE_QUEUE;
+ } else if (matches(*argv, "vnet_hdr") == 0) {
+ ifr->ifr_flags |= IFF_VNET_HDR;
+ } else if (matches(*argv, "dev") == 0) {
+ NEXT_ARG();
+ strncpy(ifr->ifr_name, *argv, IFNAMSIZ-1);
+ } else {
+ if (matches(*argv, "name") == 0) {
+ NEXT_ARG();
+ } else if (matches(*argv, "help") == 0)
+ usage();
+ if (ifr->ifr_name[0])
+ duparg2("name", *argv);
+ strncpy(ifr->ifr_name, *argv, IFNAMSIZ);
+ }
+ count++;
+ argc--; argv++;
+ }
+
+ return 0;
+}
+
+
+static int do_add(int argc, char **argv)
+{
+ struct ifreq ifr;
+ uid_t uid = -1;
+ gid_t gid = -1;
+
+ if (parse_args(argc, argv, &ifr, &uid, &gid) < 0)
+ return -1;
+
+ if (!(ifr.ifr_flags & TUN_TYPE_MASK)) {
+ fprintf(stderr, "You failed to specify a tunnel mode\n");
+ return -1;
+ }
+ return tap_add_ioctl(&ifr, uid, gid);
+}
+
+static int do_del(int argc, char **argv)
+{
+ struct ifreq ifr;
+
+ if (parse_args(argc, argv, &ifr, NULL, NULL) < 0)
+ return -1;
+
+ return tap_del_ioctl(&ifr);
+}
+
+static int read_prop(char *dev, char *prop, long *value)
+{
+ char fname[IFNAMSIZ+25], buf[80], *endp;
+ ssize_t len;
+ int fd;
+ long result;
+
+ sprintf(fname, "/sys/class/net/%s/%s", dev, prop);
+ fd = open(fname, O_RDONLY);
+ if (fd < 0) {
+ if (strcmp(prop, "tun_flags"))
+ fprintf(stderr, "open %s: %s\n", fname,
+ strerror(errno));
+ return -1;
+ }
+ len = read(fd, buf, sizeof(buf)-1);
+ close(fd);
+ if (len < 0) {
+ fprintf(stderr, "read %s: %s", fname, strerror(errno));
+ return -1;
+ }
+
+ buf[len] = 0;
+ result = strtol(buf, &endp, 0);
+ if (*endp != '\n') {
+ fprintf(stderr, "Failed to parse %s\n", fname);
+ return -1;
+ }
+ *value = result;
+ return 0;
+}
+
+static void print_flags(long flags)
+{
+ if (flags & IFF_TUN)
+ printf(" tun");
+
+ if (flags & IFF_TAP)
+ printf(" tap");
+
+ if (!(flags & IFF_NO_PI))
+ printf(" pi");
+
+ if (flags & IFF_ONE_QUEUE)
+ printf(" one_queue");
+
+ if (flags & IFF_VNET_HDR)
+ printf(" vnet_hdr");
+
+ flags &= ~(IFF_TUN|IFF_TAP|IFF_NO_PI|IFF_ONE_QUEUE|IFF_VNET_HDR);
+ if (flags)
+ printf(" UNKNOWN_FLAGS:%lx", flags);
+}
+
+static int do_show(int argc, char **argv)
+{
+ DIR *dir;
+ struct dirent *d;
+ long flags, owner = -1, group = -1;
+
+ dir = opendir("/sys/class/net");
+ if (!dir) {
+ perror("opendir");
+ return -1;
+ }
+ while ((d = readdir(dir))) {
+ if (d->d_name[0] == '.' &&
+ (d->d_name[1] == 0 || d->d_name[1] == '.'))
+ continue;
+
+ if (read_prop(d->d_name, "tun_flags", &flags))
+ continue;
+
+ read_prop(d->d_name, "owner", &owner);
+ read_prop(d->d_name, "group", &group);
+
+ printf("%s:", d->d_name);
+ print_flags(flags);
+ if (owner != -1)
+ printf(" user %ld", owner);
+ if (group != -1)
+ printf(" group %ld", group);
+ printf("\n");
+ }
+ return 0;
+}
+
+int do_iptuntap(int argc, char **argv)
+{
+ if (argc > 0) {
+ if (matches(*argv, "add") == 0)
+ return do_add(argc-1, argv+1);
+ if (matches(*argv, "del") == 0)
+ return do_del(argc-1, argv+1);
+ if (matches(*argv, "show") == 0 ||
+ matches(*argv, "lst") == 0 ||
+ matches(*argv, "list") == 0)
+ return do_show(argc-1, argv+1);
+ if (matches(*argv, "help") == 0)
+ usage();
+ } else
+ return do_show(0, NULL);
+
+ fprintf(stderr, "Command \"%s\" is unknown, try \"ip tuntap help\".\n",
+ *argv);
+ exit(-1);
+}