From patchwork Mon May 4 10:42:58 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Woodhouse X-Patchwork-Id: 26839 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@bilbo.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from ozlabs.org (ozlabs.org [203.10.76.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.ozlabs.org", Issuer "CA Cert Signing Authority" (verified OK)) by bilbo.ozlabs.org (Postfix) with ESMTPS id C62BAB7063 for ; Mon, 4 May 2009 20:43:10 +1000 (EST) Received: by ozlabs.org (Postfix) id B464EDDDA2; Mon, 4 May 2009 20:43:10 +1000 (EST) Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by ozlabs.org (Postfix) with ESMTP id 1D4B0DDD1C for ; Mon, 4 May 2009 20:43:10 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752830AbZEDKnE (ORCPT ); Mon, 4 May 2009 06:43:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751568AbZEDKnD (ORCPT ); Mon, 4 May 2009 06:43:03 -0400 Received: from casper.infradead.org ([85.118.1.10]:35580 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751706AbZEDKnA (ORCPT ); Mon, 4 May 2009 06:43:00 -0400 Received: from macbook.infradead.org ([2001:8b0:10b:1:216:eaff:fe05:bbb8]) by casper.infradead.org with esmtpsa (Exim 4.69 #1 (Red Hat Linux)) id 1M0vdT-0008H3-Eg; Mon, 04 May 2009 10:43:00 +0000 Subject: [iproute2 patch]: Add 'ip tuntap' facility for managing tun/tap devices From: David Woodhouse To: stephen.hemminger@vyatta.com Cc: netdev@vger.kernel.org In-Reply-To: <1241433136.6126.70.camel@macbook.infradead.org> References: <1241433136.6126.70.camel@macbook.infradead.org> Date: Mon, 04 May 2009 11:42:58 +0100 Message-Id: <1241433778.6126.90.camel@macbook.infradead.org> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1 (2.26.1-2.fc11) X-Bad-Reply: References and In-Reply-To but no 'Re:' in Subject. X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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 (<1241433136.6126.70.camel@macbook.infradead.org>), 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 + * + */ + +#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 ] [ 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; +} + +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 (strcmp(*argv, "mode") == 0) { + NEXT_ARG(); + if (strcmp(*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 (strcmp(*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 && strcmp(*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 && strcmp(*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 (strcmp(*argv, "pi") == 0) { + ifr->ifr_flags &= ~IFF_NO_PI; + } else if (strcmp(*argv, "one_queue") == 0) { + ifr->ifr_flags |= IFF_ONE_QUEUE; + } else if (strcmp(*argv, "vnet_hdr") == 0) { + ifr->ifr_flags |= IFF_VNET_HDR; + } else if (strcmp(*argv, "dev") == 0) { + NEXT_ARG(); + strncpy(ifr->ifr_name, *argv, IFNAMSIZ-1); + } else { + if (strcmp(*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:%x", flags); +} + +static int do_show(int argc, char **argv) +{ + DIR *dir; + struct dirent *d; + long flags, owner = -1, group = -1; + int i; + + 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); +}