1 /* 2 * iprule.c "ip rule". 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: Alexey Kuznetsov, <kuznet (at) ms2.inr.ac.ru> 10 * 11 */ 12 13 #include <stdio.h> 14 #include <stdlib.h> 15 #include <unistd.h> 16 #include <syslog.h> 17 #include <fcntl.h> 18 #include <sys/socket.h> 19 #include <netinet/in.h> 20 #include <netinet/ip.h> 21 #include <arpa/inet.h> 22 #include <string.h> 23 #include <linux/fib_rules.h> 24 25 #include "rt_names.h" 26 #include "utils.h" 27 #include "ip_common.h" 28 29 extern struct rtnl_handle rth; 30 31 static void usage(void) __attribute__((noreturn)); 32 33 static void usage(void) 34 { 35 fprintf(stderr, "Usage: ip rule [ list | add | del | flush ] SELECTOR ACTION\n"); 36 fprintf(stderr, "SELECTOR := [ not ] [ from PREFIX ] [ to PREFIX ] [ tos TOS ] [ fwmark FWMARK[/MASK] ]\n"); 37 fprintf(stderr, " [ iif STRING ] [ oif STRING ] [ pref NUMBER ] [ uidrange UID1-UID2 ]\n"); 38 fprintf(stderr, "ACTION := [ table TABLE_ID ]\n"); 39 fprintf(stderr, " [ prohibit | reject | unreachable ]\n"); 40 fprintf(stderr, " [ realms [SRCREALM/]DSTREALM ]\n"); 41 fprintf(stderr, " [ goto NUMBER ]\n"); 42 fprintf(stderr, "TABLE_ID := [ local | main | default | NUMBER ]\n"); 43 exit(-1); 44 } 45 46 int print_rule(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg) 47 { 48 FILE *fp = (FILE*)arg; 49 struct rtmsg *r = NLMSG_DATA(n); 50 int len = n->nlmsg_len; 51 int host_len = -1; 52 __u32 table, uid_start, uid_end; 53 struct rtattr * tb[FRA_MAX+1]; 54 char abuf[256]; 55 SPRINT_BUF(b1); 56 57 if (n->nlmsg_type != RTM_NEWRULE && n->nlmsg_type != RTM_DELRULE) 58 return 0; 59 60 len -= NLMSG_LENGTH(sizeof(*r)); 61 if (len < 0) 62 return -1; 63 64 parse_rtattr(tb, FRA_MAX, RTM_RTA(r), len); 65 66 if (r->rtm_family == AF_INET) 67 host_len = 32; 68 else if (r->rtm_family == AF_INET6) 69 host_len = 128; 70 else if (r->rtm_family == AF_DECnet) 71 host_len = 16; 72 else if (r->rtm_family == AF_IPX) 73 host_len = 80; 74 75 if (n->nlmsg_type == RTM_DELRULE) 76 fprintf(fp, "Deleted "); 77 78 if (tb[FRA_PRIORITY]) 79 fprintf(fp, "%u:\t", *(unsigned*)RTA_DATA(tb[FRA_PRIORITY])); 80 else 81 fprintf(fp, "0:\t"); 82 83 if (r->rtm_flags & FIB_RULE_INVERT) 84 fprintf(fp, "not "); 85 86 if (tb[FRA_SRC]) { 87 if (r->rtm_src_len != host_len) { 88 fprintf(fp, "from %s/%u ", rt_addr_n2a(r->rtm_family, 89 RTA_PAYLOAD(tb[FRA_SRC]), 90 RTA_DATA(tb[FRA_SRC]), 91 abuf, sizeof(abuf)), 92 r->rtm_src_len 93 ); 94 } else { 95 fprintf(fp, "from %s ", format_host(r->rtm_family, 96 RTA_PAYLOAD(tb[FRA_SRC]), 97 RTA_DATA(tb[FRA_SRC]), 98 abuf, sizeof(abuf)) 99 ); 100 } 101 } else if (r->rtm_src_len) { 102 fprintf(fp, "from 0/%d ", r->rtm_src_len); 103 } else { 104 fprintf(fp, "from all "); 105 } 106 107 if (tb[FRA_DST]) { 108 if (r->rtm_dst_len != host_len) { 109 fprintf(fp, "to %s/%u ", rt_addr_n2a(r->rtm_family, 110 RTA_PAYLOAD(tb[FRA_DST]), 111 RTA_DATA(tb[FRA_DST]), 112 abuf, sizeof(abuf)), 113 r->rtm_dst_len 114 ); 115 } else { 116 fprintf(fp, "to %s ", format_host(r->rtm_family, 117 RTA_PAYLOAD(tb[FRA_DST]), 118 RTA_DATA(tb[FRA_DST]), 119 abuf, sizeof(abuf))); 120 } 121 } else if (r->rtm_dst_len) { 122 fprintf(fp, "to 0/%d ", r->rtm_dst_len); 123 } 124 125 if (r->rtm_tos) { 126 SPRINT_BUF(b1); 127 fprintf(fp, "tos %s ", rtnl_dsfield_n2a(r->rtm_tos, b1, sizeof(b1))); 128 } 129 130 if (tb[FRA_FWMARK] || tb[FRA_FWMASK]) { 131 __u32 mark = 0, mask = 0; 132 133 if (tb[FRA_FWMARK]) 134 mark = rta_getattr_u32(tb[FRA_FWMARK]); 135 136 if (tb[FRA_FWMASK] && 137 (mask = rta_getattr_u32(tb[FRA_FWMASK])) != 0xFFFFFFFF) 138 fprintf(fp, "fwmark 0x%x/0x%x ", mark, mask); 139 else 140 fprintf(fp, "fwmark 0x%x ", mark); 141 } 142 143 if (tb[FRA_IFNAME]) { 144 fprintf(fp, "iif %s ", rta_getattr_str(tb[FRA_IFNAME])); 145 if (r->rtm_flags & FIB_RULE_IIF_DETACHED) 146 fprintf(fp, "[detached] "); 147 } 148 149 if (tb[FRA_OIFNAME]) { 150 fprintf(fp, "oif %s ", rta_getattr_str(tb[FRA_OIFNAME])); 151 if (r->rtm_flags & FIB_RULE_OIF_DETACHED) 152 fprintf(fp, "[detached] "); 153 } 154 155 if (tb[FRA_UID_START] || tb[FRA_UID_END]) { 156 fprintf(fp, "uidrange "); 157 if (tb[FRA_UID_START]) 158 fprintf(fp, "%u", rta_getattr_u32(tb[FRA_UID_START])); 159 else 160 fprintf(fp, "???"); 161 162 if (tb[FRA_UID_END]) 163 fprintf(fp, "-%u ", rta_getattr_u32(tb[FRA_UID_END])); 164 else 165 fprintf(fp, "-??? "); 166 } 167 168 table = rtm_get_table(r, tb); 169 if (table) 170 fprintf(fp, "lookup %s ", rtnl_rttable_n2a(table, b1, sizeof(b1))); 171 172 if (tb[FRA_FLOW]) { 173 __u32 to = rta_getattr_u32(tb[FRA_FLOW]); 174 __u32 from = to>>16; 175 to &= 0xFFFF; 176 if (from) { 177 fprintf(fp, "realms %s/", 178 rtnl_rtrealm_n2a(from, b1, sizeof(b1))); 179 } 180 fprintf(fp, "%s ", 181 rtnl_rtrealm_n2a(to, b1, sizeof(b1))); 182 } 183 184 if (r->rtm_type == RTN_NAT) { 185 if (tb[RTA_GATEWAY]) { 186 fprintf(fp, "map-to %s ", 187 format_host(r->rtm_family, 188 RTA_PAYLOAD(tb[RTA_GATEWAY]), 189 RTA_DATA(tb[RTA_GATEWAY]), 190 abuf, sizeof(abuf))); 191 } else 192 fprintf(fp, "masquerade"); 193 } else if (r->rtm_type == FR_ACT_GOTO) { 194 fprintf(fp, "goto "); 195 if (tb[FRA_GOTO]) 196 fprintf(fp, "%u", rta_getattr_u32(tb[FRA_GOTO])); 197 else 198 fprintf(fp, "none"); 199 if (r->rtm_flags & FIB_RULE_UNRESOLVED) 200 fprintf(fp, " [unresolved]"); 201 } else if (r->rtm_type == FR_ACT_NOP) 202 fprintf(fp, "nop"); 203 else if (r->rtm_type != RTN_UNICAST) 204 fprintf(fp, "%s", rtnl_rtntype_n2a(r->rtm_type, b1, sizeof(b1))); 205 206 fprintf(fp, "\n"); 207 fflush(fp); 208 return 0; 209 } 210 211 static int iprule_list(int argc, char **argv) 212 { 213 int af = preferred_family; 214 215 if (af == AF_UNSPEC) 216 af = AF_INET; 217 218 if (argc > 0) { 219 fprintf(stderr, "\"ip rule show\" does not take any arguments.\n"); 220 return -1; 221 } 222 223 if (rtnl_wilddump_request(&rth, af, RTM_GETRULE) < 0) { 224 perror("Cannot send dump request"); 225 return 1; 226 } 227 228 if (rtnl_dump_filter(&rth, print_rule, stdout) < 0) { 229 fprintf(stderr, "Dump terminated\n"); 230 return 1; 231 } 232 233 return 0; 234 } 235 236 237 static int iprule_modify(int cmd, int argc, char **argv) 238 { 239 int table_ok = 0; 240 struct { 241 struct nlmsghdr n; 242 struct rtmsg r; 243 char buf[1024]; 244 } req; 245 246 memset(&req, 0, sizeof(req)); 247 248 req.n.nlmsg_type = cmd; 249 req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg)); 250 req.n.nlmsg_flags = NLM_F_REQUEST; 251 req.r.rtm_family = preferred_family; 252 req.r.rtm_protocol = RTPROT_BOOT; 253 req.r.rtm_scope = RT_SCOPE_UNIVERSE; 254 req.r.rtm_table = 0; 255 req.r.rtm_type = RTN_UNSPEC; 256 req.r.rtm_flags = 0; 257 258 if (cmd == RTM_NEWRULE) { 259 req.n.nlmsg_flags |= NLM_F_CREATE|NLM_F_EXCL; 260 req.r.rtm_type = RTN_UNICAST; 261 } 262 263 while (argc > 0) { 264 if (strcmp(*argv, "not") == 0) { 265 req.r.rtm_flags |= FIB_RULE_INVERT; 266 } else if (strcmp(*argv, "from") == 0) { 267 inet_prefix dst; 268 NEXT_ARG(); 269 get_prefix(&dst, *argv, req.r.rtm_family); 270 req.r.rtm_src_len = dst.bitlen; 271 addattr_l(&req.n, sizeof(req), FRA_SRC, &dst.data, dst.bytelen); 272 } else if (strcmp(*argv, "to") == 0) { 273 inet_prefix dst; 274 NEXT_ARG(); 275 get_prefix(&dst, *argv, req.r.rtm_family); 276 req.r.rtm_dst_len = dst.bitlen; 277 addattr_l(&req.n, sizeof(req), FRA_DST, &dst.data, dst.bytelen); 278 } else if (matches(*argv, "preference") == 0 || 279 matches(*argv, "order") == 0 || 280 matches(*argv, "priority") == 0) { 281 __u32 pref; 282 NEXT_ARG(); 283 if (get_u32(&pref, *argv, 0)) 284 invarg("preference value is invalid\n", *argv); 285 addattr32(&req.n, sizeof(req), FRA_PRIORITY, pref); 286 } else if (strcmp(*argv, "tos") == 0 || 287 matches(*argv, "dsfield") == 0) { 288 __u32 tos; 289 NEXT_ARG(); 290 if (rtnl_dsfield_a2n(&tos, *argv)) 291 invarg("TOS value is invalid\n", *argv); 292 req.r.rtm_tos = tos; 293 } else if (strcmp(*argv, "fwmark") == 0) { 294 char *slash; 295 __u32 fwmark, fwmask; 296 NEXT_ARG(); 297 if ((slash = strchr(*argv, '/')) != NULL) 298 *slash = '\0'; 299 if (get_u32(&fwmark, *argv, 0)) 300 invarg("fwmark value is invalid\n", *argv); 301 addattr32(&req.n, sizeof(req), FRA_FWMARK, fwmark); 302 if (slash) { 303 if (get_u32(&fwmask, slash+1, 0)) 304 invarg("fwmask value is invalid\n", slash+1); 305 addattr32(&req.n, sizeof(req), FRA_FWMASK, fwmask); 306 } 307 } else if (matches(*argv, "realms") == 0) { 308 __u32 realm; 309 NEXT_ARG(); 310 if (get_rt_realms(&realm, *argv)) 311 invarg("invalid realms\n", *argv); 312 addattr32(&req.n, sizeof(req), FRA_FLOW, realm); 313 } else if (matches(*argv, "table") == 0 || 314 strcmp(*argv, "lookup") == 0) { 315 __u32 tid; 316 NEXT_ARG(); 317 if (rtnl_rttable_a2n(&tid, *argv)) 318 invarg("invalid table ID\n", *argv); 319 if (tid < 256) 320 req.r.rtm_table = tid; 321 else { 322 req.r.rtm_table = RT_TABLE_UNSPEC; 323 addattr32(&req.n, sizeof(req), FRA_TABLE, tid); 324 } 325 table_ok = 1; 326 } else if (strcmp(*argv, "dev") == 0 || 327 strcmp(*argv, "iif") == 0) { 328 NEXT_ARG(); 329 addattr_l(&req.n, sizeof(req), FRA_IFNAME, *argv, strlen(*argv)+1); 330 } else if (strcmp(*argv, "oif") == 0) { 331 NEXT_ARG(); 332 addattr_l(&req.n, sizeof(req), FRA_OIFNAME, *argv, strlen(*argv)+1); 333 } else if (strcmp(*argv, "nat") == 0 || 334 matches(*argv, "map-to") == 0) { 335 NEXT_ARG(); 336 fprintf(stderr, "Warning: route NAT is deprecated\n"); 337 addattr32(&req.n, sizeof(req), RTA_GATEWAY, get_addr32(*argv)); 338 req.r.rtm_type = RTN_NAT; 339 } else if (strcmp(*argv, "uidrange") == 0) { 340 __u32 uid_start, uid_end; 341 NEXT_ARG(); 342 if (sscanf(*argv, "%u-%u", &uid_start, &uid_end) != 2) 343 invarg("UID range is invalid\n", *argv); 344 addattr32(&req.n, sizeof(req), FRA_UID_START, uid_start); 345 addattr32(&req.n, sizeof(req), FRA_UID_END, uid_end); 346 } else { 347 int type; 348 349 if (strcmp(*argv, "type") == 0) { 350 NEXT_ARG(); 351 } 352 if (matches(*argv, "help") == 0) 353 usage(); 354 else if (matches(*argv, "goto") == 0) { 355 __u32 target; 356 type = FR_ACT_GOTO; 357 NEXT_ARG(); 358 if (get_u32(&target, *argv, 0)) 359 invarg("invalid target\n", *argv); 360 addattr32(&req.n, sizeof(req), FRA_GOTO, target); 361 } else if (matches(*argv, "nop") == 0) 362 type = FR_ACT_NOP; 363 else if (rtnl_rtntype_a2n(&type, *argv)) 364 invarg("Failed to parse rule type", *argv); 365 req.r.rtm_type = type; 366 table_ok = 1; 367 } 368 argc--; 369 argv++; 370 } 371 372 if (req.r.rtm_family == AF_UNSPEC) 373 req.r.rtm_family = AF_INET; 374 375 if (!table_ok && cmd == RTM_NEWRULE) 376 req.r.rtm_table = RT_TABLE_MAIN; 377 378 if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0) 379 return 2; 380 381 return 0; 382 } 383 384 385 static int flush_rule(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg) 386 { 387 struct rtnl_handle rth2; 388 struct rtmsg *r = NLMSG_DATA(n); 389 int len = n->nlmsg_len; 390 struct rtattr * tb[FRA_MAX+1]; 391 392 len -= NLMSG_LENGTH(sizeof(*r)); 393 if (len < 0) 394 return -1; 395 396 parse_rtattr(tb, FRA_MAX, RTM_RTA(r), len); 397 398 if (tb[FRA_PRIORITY]) { 399 n->nlmsg_type = RTM_DELRULE; 400 n->nlmsg_flags = NLM_F_REQUEST; 401 402 if (rtnl_open(&rth2, 0) < 0) 403 return -1; 404 405 if (rtnl_talk(&rth2, n, 0, 0, NULL) < 0) 406 return -2; 407 408 rtnl_close(&rth2); 409 } 410 411 return 0; 412 } 413 414 static int iprule_flush(int argc, char **argv) 415 { 416 int af = preferred_family; 417 418 if (af == AF_UNSPEC) 419 af = AF_INET; 420 421 if (argc > 0) { 422 fprintf(stderr, "\"ip rule flush\" does not allow arguments\n"); 423 return -1; 424 } 425 426 if (rtnl_wilddump_request(&rth, af, RTM_GETRULE) < 0) { 427 perror("Cannot send dump request"); 428 return 1; 429 } 430 431 if (rtnl_dump_filter(&rth, flush_rule, NULL) < 0) { 432 fprintf(stderr, "Flush terminated\n"); 433 return 1; 434 } 435 436 return 0; 437 } 438 439 int do_iprule(int argc, char **argv) 440 { 441 if (argc < 1) { 442 return iprule_list(0, NULL); 443 } else if (matches(argv[0], "list") == 0 || 444 matches(argv[0], "lst") == 0 || 445 matches(argv[0], "show") == 0) { 446 return iprule_list(argc-1, argv+1); 447 } else if (matches(argv[0], "add") == 0) { 448 return iprule_modify(RTM_NEWRULE, argc-1, argv+1); 449 } else if (matches(argv[0], "delete") == 0) { 450 return iprule_modify(RTM_DELRULE, argc-1, argv+1); 451 } else if (matches(argv[0], "flush") == 0) { 452 return iprule_flush(argc-1, argv+1); 453 } else if (matches(argv[0], "help") == 0) 454 usage(); 455 456 fprintf(stderr, "Command \"%s\" is unknown, try \"ip rule help\".\n", *argv); 457 exit(-1); 458 } 459 460 int do_multirule(int argc, char **argv) 461 { 462 switch (preferred_family) { 463 case AF_UNSPEC: 464 case AF_INET: 465 preferred_family = RTNL_FAMILY_IPMR; 466 break; 467 case AF_INET6: 468 preferred_family = RTNL_FAMILY_IP6MR; 469 break; 470 case RTNL_FAMILY_IPMR: 471 case RTNL_FAMILY_IP6MR: 472 break; 473 default: 474 fprintf(stderr, "Multicast rules are only supported for IPv4/IPv6, was: %i\n", 475 preferred_family); 476 exit(-1); 477 } 478 479 return do_iprule(argc, argv); 480 } 481
