From: David Woodhouse Date: Sat, 19 Sep 2009 16:48:43 +0000 (-0700) Subject: Add 'ip tuntap' support. X-Git-Tag: v2.6.34~15^2~2 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=580fbd88f75cc9eea0d28a48c025b090eb9419a7;p=thirdparty%2Fiproute2.git Add 'ip tuntap' support. This patch provides support for 'ip tuntap', allowing creation and deletion of persistent tun/tap devices. --- diff --git a/include/linux/if_tun.h b/include/linux/if_tun.h new file mode 100644 index 000000000..049d6c942 --- /dev/null +++ b/include/linux/if_tun.h @@ -0,0 +1,87 @@ +/* + * Universal TUN/TAP device driver. + * Copyright (C) 1999-2000 Maxim Krasnyansky + * + * 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 +#include + +/* 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 */ diff --git a/ip/Makefile b/ip/Makefile index 3c185cfbb..fd16fe947 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 iplink_can.o diff --git a/ip/ip.c b/ip/ip.c index 2bd54b2aa..d846a763e 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 273065f5f..c85766731 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 000000000..2a8aa7fc8 --- /dev/null +++ b/ip/iptuntap.c @@ -0,0 +1,323 @@ +/* + * 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 + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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); +}