1 /* 2 * link_gre.c gre driver module 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: Herbert Xu <herbert (at) gondor.apana.org.au> 10 * 11 */ 12 13 #include <string.h> 14 #include <net/if.h> 15 #include <sys/types.h> 16 #include <sys/socket.h> 17 #include <arpa/inet.h> 18 19 #include <linux/ip.h> 20 #include <linux/if_tunnel.h> 21 #include "rt_names.h" 22 #include "utils.h" 23 #include "ip_common.h" 24 #include "tunnel.h" 25 26 static void print_usage(FILE *f) 27 { 28 fprintf(f, "Usage: ip link { add | set | change | replace | del } NAME\n"); 29 fprintf(f, " type { gre | gretap } [ remote ADDR ] [ local ADDR ]\n"); 30 fprintf(f, " [ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ]\n"); 31 fprintf(f, " [ ttl TTL ] [ tos TOS ] [ [no]pmtudisc ] [ dev PHYS_DEV ]\n"); 32 fprintf(f, " [ noencap ] [ encap { fou | gue | none } ]\n"); 33 fprintf(f, " [ encap-sport PORT ] [ encap-dport PORT ]\n"); 34 fprintf(f, " [ [no]encap-csum ] [ [no]encap-csum6 ] [ [no]encap-remcsum ]\n"); 35 fprintf(f, "\n"); 36 fprintf(f, "Where: NAME := STRING\n"); 37 fprintf(f, " ADDR := { IP_ADDRESS | any }\n"); 38 fprintf(f, " TOS := { NUMBER | inherit }\n"); 39 fprintf(f, " TTL := { 1..255 | inherit }\n"); 40 fprintf(f, " KEY := { DOTTED_QUAD | NUMBER }\n"); 41 } 42 43 static void usage(void) __attribute__((noreturn)); 44 static void usage(void) 45 { 46 print_usage(stderr); 47 exit(-1); 48 } 49 50 static int gre_parse_opt(struct link_util *lu, int argc, char **argv, 51 struct nlmsghdr *n) 52 { 53 struct { 54 struct nlmsghdr n; 55 struct ifinfomsg i; 56 char buf[16384]; 57 } req; 58 struct ifinfomsg *ifi = (struct ifinfomsg *)(n + 1); 59 struct rtattr *tb[IFLA_MAX + 1]; 60 struct rtattr *linkinfo[IFLA_INFO_MAX+1]; 61 struct rtattr *greinfo[IFLA_GRE_MAX + 1]; 62 __u16 iflags = 0; 63 __u16 oflags = 0; 64 unsigned ikey = 0; 65 unsigned okey = 0; 66 unsigned saddr = 0; 67 unsigned daddr = 0; 68 unsigned link = 0; 69 __u8 pmtudisc = 1; 70 __u8 ttl = 0; 71 __u8 tos = 0; 72 int len; 73 __u16 encaptype = 0; 74 __u16 encapflags = 0; 75 __u16 encapsport = 0; 76 __u16 encapdport = 0; 77 __u8 metadata = 0; 78 79 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 80 memset(&req, 0, sizeof(req)); 81 82 req.n.nlmsg_len = NLMSG_LENGTH(sizeof(*ifi)); 83 req.n.nlmsg_flags = NLM_F_REQUEST; 84 req.n.nlmsg_type = RTM_GETLINK; 85 req.i.ifi_family = preferred_family; 86 req.i.ifi_index = ifi->ifi_index; 87 88 if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0) { 89 get_failed: 90 fprintf(stderr, 91 "Failed to get existing tunnel info.\n"); 92 return -1; 93 } 94 95 len = req.n.nlmsg_len; 96 len -= NLMSG_LENGTH(sizeof(*ifi)); 97 if (len < 0) 98 goto get_failed; 99 100 parse_rtattr(tb, IFLA_MAX, IFLA_RTA(&req.i), len); 101 102 if (!tb[IFLA_LINKINFO]) 103 goto get_failed; 104 105 parse_rtattr_nested(linkinfo, IFLA_INFO_MAX, tb[IFLA_LINKINFO]); 106 107 if (!linkinfo[IFLA_INFO_DATA]) 108 goto get_failed; 109 110 parse_rtattr_nested(greinfo, IFLA_GRE_MAX, 111 linkinfo[IFLA_INFO_DATA]); 112 113 if (greinfo[IFLA_GRE_IKEY]) 114 ikey = rta_getattr_u32(greinfo[IFLA_GRE_IKEY]); 115 116 if (greinfo[IFLA_GRE_OKEY]) 117 okey = rta_getattr_u32(greinfo[IFLA_GRE_OKEY]); 118 119 if (greinfo[IFLA_GRE_IFLAGS]) 120 iflags = rta_getattr_u16(greinfo[IFLA_GRE_IFLAGS]); 121 122 if (greinfo[IFLA_GRE_OFLAGS]) 123 oflags = rta_getattr_u16(greinfo[IFLA_GRE_OFLAGS]); 124 125 if (greinfo[IFLA_GRE_LOCAL]) 126 saddr = rta_getattr_u32(greinfo[IFLA_GRE_LOCAL]); 127 128 if (greinfo[IFLA_GRE_REMOTE]) 129 daddr = rta_getattr_u32(greinfo[IFLA_GRE_REMOTE]); 130 131 if (greinfo[IFLA_GRE_PMTUDISC]) 132 pmtudisc = rta_getattr_u8( 133 greinfo[IFLA_GRE_PMTUDISC]); 134 135 if (greinfo[IFLA_GRE_TTL]) 136 ttl = rta_getattr_u8(greinfo[IFLA_GRE_TTL]); 137 138 if (greinfo[IFLA_GRE_TOS]) 139 tos = rta_getattr_u8(greinfo[IFLA_GRE_TOS]); 140 141 if (greinfo[IFLA_GRE_LINK]) 142 link = rta_getattr_u8(greinfo[IFLA_GRE_LINK]); 143 144 if (greinfo[IFLA_GRE_ENCAP_TYPE]) 145 encaptype = rta_getattr_u16(greinfo[IFLA_GRE_ENCAP_TYPE]); 146 if (greinfo[IFLA_GRE_ENCAP_FLAGS]) 147 encapflags = rta_getattr_u16(greinfo[IFLA_GRE_ENCAP_FLAGS]); 148 if (greinfo[IFLA_GRE_ENCAP_SPORT]) 149 encapsport = rta_getattr_u16(greinfo[IFLA_GRE_ENCAP_SPORT]); 150 if (greinfo[IFLA_GRE_ENCAP_DPORT]) 151 encapdport = rta_getattr_u16(greinfo[IFLA_GRE_ENCAP_DPORT]); 152 153 if (greinfo[IFLA_GRE_COLLECT_METADATA]) 154 metadata = 1; 155 } 156 157 while (argc > 0) { 158 if (!matches(*argv, "key")) { 159 unsigned uval; 160 161 NEXT_ARG(); 162 iflags |= GRE_KEY; 163 oflags |= GRE_KEY; 164 if (strchr(*argv, '.')) 165 uval = get_addr32(*argv); 166 else { 167 if (get_unsigned(&uval, *argv, 0) < 0) { 168 fprintf(stderr, 169 "Invalid value for \"key\": \"%s\"; it should be an unsigned integer\n", *argv); 170 exit(-1); 171 } 172 uval = htonl(uval); 173 } 174 175 ikey = okey = uval; 176 } else if (!matches(*argv, "ikey")) { 177 unsigned uval; 178 179 NEXT_ARG(); 180 iflags |= GRE_KEY; 181 if (strchr(*argv, '.')) 182 uval = get_addr32(*argv); 183 else { 184 if (get_unsigned(&uval, *argv, 0)<0) { 185 fprintf(stderr, "invalid value for \"ikey\": \"%s\"; it should be an unsigned integer\n", *argv); 186 exit(-1); 187 } 188 uval = htonl(uval); 189 } 190 ikey = uval; 191 } else if (!matches(*argv, "okey")) { 192 unsigned uval; 193 194 NEXT_ARG(); 195 oflags |= GRE_KEY; 196 if (strchr(*argv, '.')) 197 uval = get_addr32(*argv); 198 else { 199 if (get_unsigned(&uval, *argv, 0)<0) { 200 fprintf(stderr, "invalid value for \"okey\": \"%s\"; it should be an unsigned integer\n", *argv); 201 exit(-1); 202 } 203 uval = htonl(uval); 204 } 205 okey = uval; 206 } else if (!matches(*argv, "seq")) { 207 iflags |= GRE_SEQ; 208 oflags |= GRE_SEQ; 209 } else if (!matches(*argv, "iseq")) { 210 iflags |= GRE_SEQ; 211 } else if (!matches(*argv, "oseq")) { 212 oflags |= GRE_SEQ; 213 } else if (!matches(*argv, "csum")) { 214 iflags |= GRE_CSUM; 215 oflags |= GRE_CSUM; 216 } else if (!matches(*argv, "icsum")) { 217 iflags |= GRE_CSUM; 218 } else if (!matches(*argv, "ocsum")) { 219 oflags |= GRE_CSUM; 220 } else if (!matches(*argv, "nopmtudisc")) { 221 pmtudisc = 0; 222 } else if (!matches(*argv, "pmtudisc")) { 223 pmtudisc = 1; 224 } else if (!matches(*argv, "remote")) { 225 NEXT_ARG(); 226 if (strcmp(*argv, "any")) 227 daddr = get_addr32(*argv); 228 } else if (!matches(*argv, "local")) { 229 NEXT_ARG(); 230 if (strcmp(*argv, "any")) 231 saddr = get_addr32(*argv); 232 } else if (!matches(*argv, "dev")) { 233 NEXT_ARG(); 234 link = if_nametoindex(*argv); 235 if (link == 0) { 236 fprintf(stderr, "Cannot find device \"%s\"\n", 237 *argv); 238 exit(-1); 239 } 240 } else if (!matches(*argv, "ttl") || 241 !matches(*argv, "hoplimit")) { 242 unsigned uval; 243 244 NEXT_ARG(); 245 if (strcmp(*argv, "inherit") != 0) { 246 if (get_unsigned(&uval, *argv, 0)) 247 invarg("invalid TTL\n", *argv); 248 if (uval > 255) 249 invarg("TTL must be <= 255\n", *argv); 250 ttl = uval; 251 } 252 } else if (!matches(*argv, "tos") || 253 !matches(*argv, "tclass") || 254 !matches(*argv, "dsfield")) { 255 __u32 uval; 256 257 NEXT_ARG(); 258 if (strcmp(*argv, "inherit") != 0) { 259 if (rtnl_dsfield_a2n(&uval, *argv)) 260 invarg("bad TOS value", *argv); 261 tos = uval; 262 } else 263 tos = 1; 264 } else if (strcmp(*argv, "noencap") == 0) { 265 encaptype = TUNNEL_ENCAP_NONE; 266 } else if (strcmp(*argv, "encap") == 0) { 267 NEXT_ARG(); 268 if (strcmp(*argv, "fou") == 0) 269 encaptype = TUNNEL_ENCAP_FOU; 270 else if (strcmp(*argv, "gue") == 0) 271 encaptype = TUNNEL_ENCAP_GUE; 272 else if (strcmp(*argv, "none") == 0) 273 encaptype = TUNNEL_ENCAP_NONE; 274 else 275 invarg("Invalid encap type.", *argv); 276 } else if (strcmp(*argv, "encap-sport") == 0) { 277 NEXT_ARG(); 278 if (strcmp(*argv, "auto") == 0) 279 encapsport = 0; 280 else if (get_u16(&encapsport, *argv, 0)) 281 invarg("Invalid source port.", *argv); 282 } else if (strcmp(*argv, "encap-dport") == 0) { 283 NEXT_ARG(); 284 if (get_u16(&encapdport, *argv, 0)) 285 invarg("Invalid destination port.", *argv); 286 } else if (strcmp(*argv, "encap-csum") == 0) { 287 encapflags |= TUNNEL_ENCAP_FLAG_CSUM; 288 } else if (strcmp(*argv, "noencap-csum") == 0) { 289 encapflags &= ~TUNNEL_ENCAP_FLAG_CSUM; 290 } else if (strcmp(*argv, "encap-udp6-csum") == 0) { 291 encapflags |= TUNNEL_ENCAP_FLAG_CSUM6; 292 } else if (strcmp(*argv, "noencap-udp6-csum") == 0) { 293 encapflags |= ~TUNNEL_ENCAP_FLAG_CSUM6; 294 } else if (strcmp(*argv, "encap-remcsum") == 0) { 295 encapflags |= TUNNEL_ENCAP_FLAG_REMCSUM; 296 } else if (strcmp(*argv, "noencap-remcsum") == 0) { 297 encapflags |= ~TUNNEL_ENCAP_FLAG_REMCSUM; 298 } else if (strcmp(*argv, "external") == 0) { 299 metadata = 1; 300 } else 301 usage(); 302 argc--; argv++; 303 } 304 305 if (!ikey && IN_MULTICAST(ntohl(daddr))) { 306 ikey = daddr; 307 iflags |= GRE_KEY; 308 } 309 if (!okey && IN_MULTICAST(ntohl(daddr))) { 310 okey = daddr; 311 oflags |= GRE_KEY; 312 } 313 if (IN_MULTICAST(ntohl(daddr)) && !saddr) { 314 fprintf(stderr, "A broadcast tunnel requires a source address.\n"); 315 return -1; 316 } 317 318 addattr32(n, 1024, IFLA_GRE_IKEY, ikey); 319 addattr32(n, 1024, IFLA_GRE_OKEY, okey); 320 addattr_l(n, 1024, IFLA_GRE_IFLAGS, &iflags, 2); 321 addattr_l(n, 1024, IFLA_GRE_OFLAGS, &oflags, 2); 322 addattr_l(n, 1024, IFLA_GRE_LOCAL, &saddr, 4); 323 addattr_l(n, 1024, IFLA_GRE_REMOTE, &daddr, 4); 324 addattr_l(n, 1024, IFLA_GRE_PMTUDISC, &pmtudisc, 1); 325 if (link) 326 addattr32(n, 1024, IFLA_GRE_LINK, link); 327 addattr_l(n, 1024, IFLA_GRE_TTL, &ttl, 1); 328 addattr_l(n, 1024, IFLA_GRE_TOS, &tos, 1); 329 330 addattr16(n, 1024, IFLA_GRE_ENCAP_TYPE, encaptype); 331 addattr16(n, 1024, IFLA_GRE_ENCAP_FLAGS, encapflags); 332 addattr16(n, 1024, IFLA_GRE_ENCAP_SPORT, htons(encapsport)); 333 addattr16(n, 1024, IFLA_GRE_ENCAP_DPORT, htons(encapdport)); 334 if (metadata) 335 addattr_l(n, 1024, IFLA_GRE_COLLECT_METADATA, NULL, 0); 336 337 return 0; 338 } 339 340 static void gre_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[]) 341 { 342 char s1[1024]; 343 char s2[64]; 344 const char *local = "any"; 345 const char *remote = "any"; 346 unsigned iflags = 0; 347 unsigned oflags = 0; 348 349 if (!tb) 350 return; 351 352 if (tb[IFLA_GRE_REMOTE]) { 353 unsigned addr = rta_getattr_u32(tb[IFLA_GRE_REMOTE]); 354 355 if (addr) 356 remote = format_host(AF_INET, 4, &addr, s1, sizeof(s1)); 357 } 358 359 fprintf(f, "remote %s ", remote); 360 361 if (tb[IFLA_GRE_LOCAL]) { 362 unsigned addr = rta_getattr_u32(tb[IFLA_GRE_LOCAL]); 363 364 if (addr) 365 local = format_host(AF_INET, 4, &addr, s1, sizeof(s1)); 366 } 367 368 fprintf(f, "local %s ", local); 369 370 if (tb[IFLA_GRE_LINK] && rta_getattr_u32(tb[IFLA_GRE_LINK])) { 371 unsigned link = rta_getattr_u32(tb[IFLA_GRE_LINK]); 372 const char *n = if_indextoname(link, s2); 373 374 if (n) 375 fprintf(f, "dev %s ", n); 376 else 377 fprintf(f, "dev %u ", link); 378 } 379 380 if (tb[IFLA_GRE_TTL] && rta_getattr_u8(tb[IFLA_GRE_TTL])) 381 fprintf(f, "ttl %d ", rta_getattr_u8(tb[IFLA_GRE_TTL])); 382 else 383 fprintf(f, "ttl inherit "); 384 385 if (tb[IFLA_GRE_TOS] && rta_getattr_u8(tb[IFLA_GRE_TOS])) { 386 int tos = rta_getattr_u8(tb[IFLA_GRE_TOS]); 387 388 fputs("tos ", f); 389 if (tos == 1) 390 fputs("inherit ", f); 391 else 392 fprintf(f, "0x%x ", tos); 393 } 394 395 if (tb[IFLA_GRE_PMTUDISC] && 396 !rta_getattr_u8(tb[IFLA_GRE_PMTUDISC])) 397 fputs("nopmtudisc ", f); 398 399 if (tb[IFLA_GRE_IFLAGS]) 400 iflags = rta_getattr_u16(tb[IFLA_GRE_IFLAGS]); 401 402 if (tb[IFLA_GRE_OFLAGS]) 403 oflags = rta_getattr_u16(tb[IFLA_GRE_OFLAGS]); 404 405 if ((iflags & GRE_KEY) && tb[IFLA_GRE_IKEY]) { 406 inet_ntop(AF_INET, RTA_DATA(tb[IFLA_GRE_IKEY]), s2, sizeof(s2)); 407 fprintf(f, "ikey %s ", s2); 408 } 409 410 if ((oflags & GRE_KEY) && tb[IFLA_GRE_OKEY]) { 411 inet_ntop(AF_INET, RTA_DATA(tb[IFLA_GRE_OKEY]), s2, sizeof(s2)); 412 fprintf(f, "okey %s ", s2); 413 } 414 415 if (iflags & GRE_SEQ) 416 fputs("iseq ", f); 417 if (oflags & GRE_SEQ) 418 fputs("oseq ", f); 419 if (iflags & GRE_CSUM) 420 fputs("icsum ", f); 421 if (oflags & GRE_CSUM) 422 fputs("ocsum ", f); 423 424 if (tb[IFLA_GRE_COLLECT_METADATA]) 425 fputs("external ", f); 426 427 if (tb[IFLA_GRE_ENCAP_TYPE] && 428 *(__u16 *)RTA_DATA(tb[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE) { 429 __u16 type = rta_getattr_u16(tb[IFLA_GRE_ENCAP_TYPE]); 430 __u16 flags = rta_getattr_u16(tb[IFLA_GRE_ENCAP_FLAGS]); 431 __u16 sport = rta_getattr_u16(tb[IFLA_GRE_ENCAP_SPORT]); 432 __u16 dport = rta_getattr_u16(tb[IFLA_GRE_ENCAP_DPORT]); 433 434 fputs("encap ", f); 435 switch (type) { 436 case TUNNEL_ENCAP_FOU: 437 fputs("fou ", f); 438 break; 439 case TUNNEL_ENCAP_GUE: 440 fputs("gue ", f); 441 break; 442 default: 443 fputs("unknown ", f); 444 break; 445 } 446 447 if (sport == 0) 448 fputs("encap-sport auto ", f); 449 else 450 fprintf(f, "encap-sport %u", ntohs(sport)); 451 452 fprintf(f, "encap-dport %u ", ntohs(dport)); 453 454 if (flags & TUNNEL_ENCAP_FLAG_CSUM) 455 fputs("encap-csum ", f); 456 else 457 fputs("noencap-csum ", f); 458 459 if (flags & TUNNEL_ENCAP_FLAG_CSUM6) 460 fputs("encap-csum6 ", f); 461 else 462 fputs("noencap-csum6 ", f); 463 464 if (flags & TUNNEL_ENCAP_FLAG_REMCSUM) 465 fputs("encap-remcsum ", f); 466 else 467 fputs("noencap-remcsum ", f); 468 } 469 } 470 471 static void gre_print_help(struct link_util *lu, int argc, char **argv, 472 FILE *f) 473 { 474 print_usage(f); 475 } 476 477 struct link_util gre_link_util = { 478 .id = "gre", 479 .maxattr = IFLA_GRE_MAX, 480 .parse_opt = gre_parse_opt, 481 .print_opt = gre_print_opt, 482 .print_help = gre_print_help, 483 }; 484 485 struct link_util gretap_link_util = { 486 .id = "gretap", 487 .maxattr = IFLA_GRE_MAX, 488 .parse_opt = gre_parse_opt, 489 .print_opt = gre_print_opt, 490 .print_help = gre_print_help, 491 }; 492