David Woodhouse | 580fbd8 | 2009-09-19 09:48:43 -0700 | [diff] [blame] | 1 | /* |
| 2 | * iptunnel.c "ip tuntap" |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public License |
| 6 | * as published by the Free Software Foundation; either version |
| 7 | * 2 of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * Authors: David Woodhouse <David.Woodhouse@intel.com> |
| 10 | * |
| 11 | */ |
| 12 | |
| 13 | #include <stdio.h> |
| 14 | #include <stdlib.h> |
| 15 | #include <string.h> |
| 16 | #include <unistd.h> |
| 17 | #include <sys/types.h> |
| 18 | #include <sys/socket.h> |
| 19 | #include <arpa/inet.h> |
| 20 | #include <sys/ioctl.h> |
| 21 | #include <linux/if.h> |
| 22 | #include <linux/if_tun.h> |
| 23 | #include <pwd.h> |
| 24 | #include <grp.h> |
| 25 | #include <fcntl.h> |
| 26 | #include <dirent.h> |
| 27 | #include <errno.h> |
| 28 | |
| 29 | #include "rt_names.h" |
| 30 | #include "utils.h" |
| 31 | #include "ip_common.h" |
| 32 | |
| 33 | #define TUNDEV "/dev/net/tun" |
| 34 | |
| 35 | static void usage(void) __attribute__((noreturn)); |
| 36 | |
| 37 | static void usage(void) |
| 38 | { |
vadimk | 08ce8ae | 2014-09-17 00:24:11 +0300 | [diff] [blame] | 39 | fprintf(stderr, "Usage: ip tuntap { add | del | show | list | lst | help } [ dev PHYS_DEV ] \n"); |
David Woodhouse | 580fbd8 | 2009-09-19 09:48:43 -0700 | [diff] [blame] | 40 | fprintf(stderr, " [ mode { tun | tap } ] [ user USER ] [ group GROUP ]\n"); |
Sriram Narasimhan | c41e038 | 2013-05-23 12:36:29 +0000 | [diff] [blame] | 41 | fprintf(stderr, " [ one_queue ] [ pi ] [ vnet_hdr ] [ multi_queue ]\n"); |
David Woodhouse | 580fbd8 | 2009-09-19 09:48:43 -0700 | [diff] [blame] | 42 | fprintf(stderr, "\n"); |
| 43 | fprintf(stderr, "Where: USER := { STRING | NUMBER }\n"); |
| 44 | fprintf(stderr, " GROUP := { STRING | NUMBER }\n"); |
| 45 | exit(-1); |
| 46 | } |
| 47 | |
| 48 | static int tap_add_ioctl(struct ifreq *ifr, uid_t uid, gid_t gid) |
| 49 | { |
Dan McGee | 1313ceb | 2011-08-31 12:14:51 -0700 | [diff] [blame] | 50 | int fd; |
David Woodhouse | 580fbd8 | 2009-09-19 09:48:43 -0700 | [diff] [blame] | 51 | int ret = -1; |
| 52 | |
| 53 | #ifdef IFF_TUN_EXCL |
| 54 | ifr->ifr_flags |= IFF_TUN_EXCL; |
| 55 | #endif |
| 56 | |
| 57 | fd = open(TUNDEV, O_RDWR); |
| 58 | if (fd < 0) { |
| 59 | perror("open"); |
| 60 | return -1; |
| 61 | } |
| 62 | if (ioctl(fd, TUNSETIFF, ifr)) { |
| 63 | perror("ioctl(TUNSETIFF)"); |
| 64 | goto out; |
| 65 | } |
| 66 | if (uid != -1 && ioctl(fd, TUNSETOWNER, uid)) { |
| 67 | perror("ioctl(TUNSETOWNER)"); |
| 68 | goto out; |
| 69 | } |
| 70 | if (gid != -1 && ioctl(fd, TUNSETGROUP, gid)) { |
| 71 | perror("ioctl(TUNSETGROUP)"); |
| 72 | goto out; |
| 73 | } |
| 74 | if (ioctl(fd, TUNSETPERSIST, 1)) { |
| 75 | perror("ioctl(TUNSETPERSIST)"); |
| 76 | goto out; |
| 77 | } |
| 78 | ret = 0; |
| 79 | out: |
| 80 | close(fd); |
| 81 | return ret; |
| 82 | } |
| 83 | |
| 84 | static int tap_del_ioctl(struct ifreq *ifr) |
| 85 | { |
| 86 | int fd = open(TUNDEV, O_RDWR); |
| 87 | int ret = -1; |
| 88 | |
| 89 | if (fd < 0) { |
| 90 | perror("open"); |
| 91 | return -1; |
| 92 | } |
| 93 | if (ioctl(fd, TUNSETIFF, ifr)) { |
| 94 | perror("ioctl(TUNSETIFF)"); |
| 95 | goto out; |
| 96 | } |
| 97 | if (ioctl(fd, TUNSETPERSIST, 0)) { |
| 98 | perror("ioctl(TUNSETPERSIST)"); |
| 99 | goto out; |
| 100 | } |
| 101 | ret = 0; |
| 102 | out: |
| 103 | close(fd); |
| 104 | return ret; |
| 105 | |
| 106 | } |
| 107 | static int parse_args(int argc, char **argv, struct ifreq *ifr, uid_t *uid, gid_t *gid) |
| 108 | { |
| 109 | int count = 0; |
| 110 | |
| 111 | memset(ifr, 0, sizeof(*ifr)); |
| 112 | |
| 113 | ifr->ifr_flags |= IFF_NO_PI; |
| 114 | |
| 115 | while (argc > 0) { |
| 116 | if (matches(*argv, "mode") == 0) { |
| 117 | NEXT_ARG(); |
| 118 | if (matches(*argv, "tun") == 0) { |
| 119 | if (ifr->ifr_flags & IFF_TAP) { |
| 120 | fprintf(stderr,"You managed to ask for more than one tunnel mode.\n"); |
| 121 | exit(-1); |
| 122 | } |
| 123 | ifr->ifr_flags |= IFF_TUN; |
| 124 | } else if (matches(*argv, "tap") == 0) { |
| 125 | if (ifr->ifr_flags & IFF_TUN) { |
| 126 | fprintf(stderr,"You managed to ask for more than one tunnel mode.\n"); |
| 127 | exit(-1); |
| 128 | } |
| 129 | ifr->ifr_flags |= IFF_TAP; |
| 130 | } else { |
Kees van Reeuwijk | 14645ec | 2013-02-08 03:32:36 +0000 | [diff] [blame] | 131 | fprintf(stderr,"Unknown tunnel mode \"%s\"\n", *argv); |
David Woodhouse | 580fbd8 | 2009-09-19 09:48:43 -0700 | [diff] [blame] | 132 | exit(-1); |
| 133 | } |
| 134 | } else if (uid && matches(*argv, "user") == 0) { |
| 135 | char *end; |
| 136 | unsigned long user; |
| 137 | |
| 138 | NEXT_ARG(); |
| 139 | if (**argv && ((user = strtol(*argv, &end, 10)), !*end)) |
| 140 | *uid = user; |
| 141 | else { |
| 142 | struct passwd *pw = getpwnam(*argv); |
| 143 | if (!pw) { |
| 144 | fprintf(stderr, "invalid user \"%s\"\n", *argv); |
| 145 | exit(-1); |
| 146 | } |
| 147 | *uid = pw->pw_uid; |
| 148 | } |
| 149 | } else if (gid && matches(*argv, "group") == 0) { |
| 150 | char *end; |
| 151 | unsigned long group; |
| 152 | |
| 153 | NEXT_ARG(); |
| 154 | |
| 155 | if (**argv && ((group = strtol(*argv, &end, 10)), !*end)) |
| 156 | *gid = group; |
| 157 | else { |
| 158 | struct group *gr = getgrnam(*argv); |
| 159 | if (!gr) { |
| 160 | fprintf(stderr, "invalid group \"%s\"\n", *argv); |
| 161 | exit(-1); |
| 162 | } |
| 163 | *gid = gr->gr_gid; |
| 164 | } |
| 165 | } else if (matches(*argv, "pi") == 0) { |
| 166 | ifr->ifr_flags &= ~IFF_NO_PI; |
| 167 | } else if (matches(*argv, "one_queue") == 0) { |
| 168 | ifr->ifr_flags |= IFF_ONE_QUEUE; |
| 169 | } else if (matches(*argv, "vnet_hdr") == 0) { |
| 170 | ifr->ifr_flags |= IFF_VNET_HDR; |
Sriram Narasimhan | c41e038 | 2013-05-23 12:36:29 +0000 | [diff] [blame] | 171 | } else if (matches(*argv, "multi_queue") == 0) { |
| 172 | ifr->ifr_flags |= IFF_MULTI_QUEUE; |
David Woodhouse | 580fbd8 | 2009-09-19 09:48:43 -0700 | [diff] [blame] | 173 | } else if (matches(*argv, "dev") == 0) { |
| 174 | NEXT_ARG(); |
| 175 | strncpy(ifr->ifr_name, *argv, IFNAMSIZ-1); |
| 176 | } else { |
| 177 | if (matches(*argv, "name") == 0) { |
| 178 | NEXT_ARG(); |
| 179 | } else if (matches(*argv, "help") == 0) |
| 180 | usage(); |
| 181 | if (ifr->ifr_name[0]) |
| 182 | duparg2("name", *argv); |
| 183 | strncpy(ifr->ifr_name, *argv, IFNAMSIZ); |
| 184 | } |
| 185 | count++; |
| 186 | argc--; argv++; |
| 187 | } |
| 188 | |
vadimk | f1a505a | 2014-09-16 23:54:34 +0300 | [diff] [blame] | 189 | if (!(ifr->ifr_flags & TUN_TYPE_MASK)) { |
| 190 | fprintf(stderr, "You failed to specify a tunnel mode\n"); |
| 191 | return -1; |
| 192 | } |
| 193 | |
David Woodhouse | 580fbd8 | 2009-09-19 09:48:43 -0700 | [diff] [blame] | 194 | return 0; |
| 195 | } |
| 196 | |
| 197 | |
| 198 | static int do_add(int argc, char **argv) |
| 199 | { |
| 200 | struct ifreq ifr; |
| 201 | uid_t uid = -1; |
| 202 | gid_t gid = -1; |
| 203 | |
| 204 | if (parse_args(argc, argv, &ifr, &uid, &gid) < 0) |
| 205 | return -1; |
| 206 | |
David Woodhouse | 580fbd8 | 2009-09-19 09:48:43 -0700 | [diff] [blame] | 207 | return tap_add_ioctl(&ifr, uid, gid); |
| 208 | } |
| 209 | |
| 210 | static int do_del(int argc, char **argv) |
| 211 | { |
| 212 | struct ifreq ifr; |
| 213 | |
| 214 | if (parse_args(argc, argv, &ifr, NULL, NULL) < 0) |
| 215 | return -1; |
| 216 | |
| 217 | return tap_del_ioctl(&ifr); |
| 218 | } |
| 219 | |
| 220 | static int read_prop(char *dev, char *prop, long *value) |
| 221 | { |
| 222 | char fname[IFNAMSIZ+25], buf[80], *endp; |
| 223 | ssize_t len; |
| 224 | int fd; |
| 225 | long result; |
| 226 | |
| 227 | sprintf(fname, "/sys/class/net/%s/%s", dev, prop); |
| 228 | fd = open(fname, O_RDONLY); |
| 229 | if (fd < 0) { |
| 230 | if (strcmp(prop, "tun_flags")) |
| 231 | fprintf(stderr, "open %s: %s\n", fname, |
| 232 | strerror(errno)); |
| 233 | return -1; |
| 234 | } |
| 235 | len = read(fd, buf, sizeof(buf)-1); |
| 236 | close(fd); |
| 237 | if (len < 0) { |
| 238 | fprintf(stderr, "read %s: %s", fname, strerror(errno)); |
| 239 | return -1; |
| 240 | } |
| 241 | |
| 242 | buf[len] = 0; |
| 243 | result = strtol(buf, &endp, 0); |
| 244 | if (*endp != '\n') { |
| 245 | fprintf(stderr, "Failed to parse %s\n", fname); |
| 246 | return -1; |
| 247 | } |
| 248 | *value = result; |
| 249 | return 0; |
| 250 | } |
| 251 | |
| 252 | static void print_flags(long flags) |
| 253 | { |
| 254 | if (flags & IFF_TUN) |
| 255 | printf(" tun"); |
| 256 | |
| 257 | if (flags & IFF_TAP) |
| 258 | printf(" tap"); |
| 259 | |
| 260 | if (!(flags & IFF_NO_PI)) |
| 261 | printf(" pi"); |
| 262 | |
| 263 | if (flags & IFF_ONE_QUEUE) |
| 264 | printf(" one_queue"); |
| 265 | |
| 266 | if (flags & IFF_VNET_HDR) |
| 267 | printf(" vnet_hdr"); |
| 268 | |
| 269 | flags &= ~(IFF_TUN|IFF_TAP|IFF_NO_PI|IFF_ONE_QUEUE|IFF_VNET_HDR); |
| 270 | if (flags) |
| 271 | printf(" UNKNOWN_FLAGS:%lx", flags); |
| 272 | } |
| 273 | |
| 274 | static int do_show(int argc, char **argv) |
| 275 | { |
| 276 | DIR *dir; |
| 277 | struct dirent *d; |
| 278 | long flags, owner = -1, group = -1; |
| 279 | |
| 280 | dir = opendir("/sys/class/net"); |
| 281 | if (!dir) { |
| 282 | perror("opendir"); |
| 283 | return -1; |
| 284 | } |
| 285 | while ((d = readdir(dir))) { |
| 286 | if (d->d_name[0] == '.' && |
| 287 | (d->d_name[1] == 0 || d->d_name[1] == '.')) |
| 288 | continue; |
| 289 | |
| 290 | if (read_prop(d->d_name, "tun_flags", &flags)) |
| 291 | continue; |
| 292 | |
| 293 | read_prop(d->d_name, "owner", &owner); |
| 294 | read_prop(d->d_name, "group", &group); |
| 295 | |
| 296 | printf("%s:", d->d_name); |
| 297 | print_flags(flags); |
| 298 | if (owner != -1) |
| 299 | printf(" user %ld", owner); |
| 300 | if (group != -1) |
| 301 | printf(" group %ld", group); |
| 302 | printf("\n"); |
| 303 | } |
Thomas Jarosch | e9a927d | 2011-10-03 05:23:42 +0000 | [diff] [blame] | 304 | closedir(dir); |
David Woodhouse | 580fbd8 | 2009-09-19 09:48:43 -0700 | [diff] [blame] | 305 | return 0; |
| 306 | } |
| 307 | |
| 308 | int do_iptuntap(int argc, char **argv) |
| 309 | { |
| 310 | if (argc > 0) { |
| 311 | if (matches(*argv, "add") == 0) |
| 312 | return do_add(argc-1, argv+1); |
Andreas Henriksson | 6e30461 | 2012-05-19 16:08:21 +0200 | [diff] [blame] | 313 | if (matches(*argv, "delete") == 0) |
David Woodhouse | 580fbd8 | 2009-09-19 09:48:43 -0700 | [diff] [blame] | 314 | return do_del(argc-1, argv+1); |
| 315 | if (matches(*argv, "show") == 0 || |
| 316 | matches(*argv, "lst") == 0 || |
| 317 | matches(*argv, "list") == 0) |
| 318 | return do_show(argc-1, argv+1); |
| 319 | if (matches(*argv, "help") == 0) |
| 320 | usage(); |
| 321 | } else |
| 322 | return do_show(0, NULL); |
| 323 | |
| 324 | fprintf(stderr, "Command \"%s\" is unknown, try \"ip tuntap help\".\n", |
| 325 | *argv); |
| 326 | exit(-1); |
| 327 | } |