ip/ipneigh.c

   1 /*
   2  * ipneigh.c            "ip neigh".
   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@ms2.inr.ac.ru>
  10  *
  11  */
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <unistd.h>
  16 #include <fcntl.h>
  17 #include <string.h>
  18 #include <sys/time.h>
  19 #include <sys/socket.h>
  20 #include <netinet/in.h>
  21 #include <netinet/ip.h>
  22
  23 #include "rt_names.h"
  24 #include "utils.h"
  25 #include "ip_common.h"
  26 #include "json_print.h"
  27
  28 #define NUD_VALID       (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
  29 #define MAX_ROUNDS      10
  30
  31 static struct
  32 {
  33         int family;
  34         int index;
  35         int state;
  36         int unused_only;
  37         inet_prefix pfx;
  38         int flushed;
  39         char *flushb;
  40         int flushp;
  41         int flushe;
  42         int master;
  43 } filter;
  44
  45 static void usage(void) __attribute__((noreturn));
  46
  47 static void usage(void)
  48 {
  49         fprintf(stderr, "Usage: ip neigh { add | del | change | replace }\n"
  50                         "                { ADDR [ lladdr LLADDR ] [ nud STATE ] | proxy ADDR } [ dev DEV ]\n");
  51         fprintf(stderr, "                                 [ router ]\n\n");
  52         fprintf(stderr, "       ip neigh { show | flush } [ proxy ] [ to PREFIX ] [ dev DEV ] [ nud STATE ]\n");
  53         fprintf(stderr, "                                 [ vrf NAME ]\n\n");
  54         fprintf(stderr, "STATE := { permanent | noarp | stale | reachable | none |\n"
  55                         "           incomplete | delay | probe | failed }\n");
  56         exit(-1);
  57 }
  58
  59 static int nud_state_a2n(unsigned int *state, const char *arg)
  60 {
  61         if (matches(arg, "permanent") == 0)
  62                 *state = NUD_PERMANENT;
  63         else if (matches(arg, "reachable") == 0)
  64                 *state = NUD_REACHABLE;
  65         else if (strcmp(arg, "noarp") == 0)
  66                 *state = NUD_NOARP;
  67         else if (strcmp(arg, "none") == 0)
  68                 *state = NUD_NONE;
  69         else if (strcmp(arg, "stale") == 0)
  70                 *state = NUD_STALE;
  71         else if (strcmp(arg, "incomplete") == 0)
  72                 *state = NUD_INCOMPLETE;
  73         else if (strcmp(arg, "delay") == 0)
  74                 *state = NUD_DELAY;
  75         else if (strcmp(arg, "probe") == 0)
  76                 *state = NUD_PROBE;
  77         else if (matches(arg, "failed") == 0)
  78                 *state = NUD_FAILED;
  79         else {
  80                 if (get_unsigned(state, arg, 0))
  81                         return -1;
  82                 if (*state >= 0x100 || (*state&((*state)-1)))
  83                         return -1;
  84         }
  85         return 0;
  86 }
  87
  88 static int flush_update(void)
  89 {
  90         if (rtnl_send_check(&rth, filter.flushb, filter.flushp) < 0) {
  91                 perror("Failed to send flush request");
  92                 return -1;
  93         }
  94         filter.flushp = 0;
  95         return 0;
  96 }
  97
  98
  99 static int ipneigh_modify(int cmd, int flags, int argc, char **argv)
 100 {
 101         struct {
 102                 struct nlmsghdr n;
 103                 struct ndmsg            ndm;
 104                 char                    buf[256];
 105         } req = {
 106                 .n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),
 107                 .n.nlmsg_flags = NLM_F_REQUEST | flags,
 108                 .n.nlmsg_type = cmd,
 109                 .ndm.ndm_family = preferred_family,
 110                 .ndm.ndm_state = NUD_PERMANENT,
 111         };
 112         char  *dev = NULL;
 113         int dst_ok = 0;
 114         int dev_ok = 0;
 115         int lladdr_ok = 0;
 116         char *lla = NULL;
 117         inet_prefix dst;
 118
 119         while (argc > 0) {
 120                 if (matches(*argv, "lladdr") == 0) {
 121                         NEXT_ARG();
 122                         if (lladdr_ok)
 123                                 duparg("lladdr", *argv);
 124                         lla = *argv;
 125                         lladdr_ok = 1;
 126                 } else if (strcmp(*argv, "nud") == 0) {
 127                         unsigned int state;
 128
 129                         NEXT_ARG();
 130                         if (nud_state_a2n(&state, *argv))
 131                                 invarg("nud state is bad", *argv);
 132                         req.ndm.ndm_state = state;
 133                 } else if (matches(*argv, "proxy") == 0) {
 134                         NEXT_ARG();
 135                         if (matches(*argv, "help") == 0)
 136                                 usage();
 137                         if (dst_ok)
 138                                 duparg("address", *argv);
 139                         get_addr(&dst, *argv, preferred_family);
 140                         dst_ok = 1;
 141                         dev_ok = 1;
 142                         req.ndm.ndm_flags |= NTF_PROXY;
 143                 } else if (strcmp(*argv, "router") == 0) {
 144                         req.ndm.ndm_flags |= NTF_ROUTER;
 145                 } else if (strcmp(*argv, "dev") == 0) {
 146                         NEXT_ARG();
 147                         dev = *argv;
 148                         dev_ok = 1;
 149                 } else {
 150                         if (strcmp(*argv, "to") == 0) {
 151                                 NEXT_ARG();
 152                         }
 153                         if (matches(*argv, "help") == 0) {
 154                                 NEXT_ARG();
 155                         }
 156                         if (dst_ok)
 157                                 duparg2("to", *argv);
 158                         get_addr(&dst, *argv, preferred_family);
 159                         dst_ok = 1;
 160                 }
 161                 argc--; argv++;
 162         }
 163         if (!dev_ok || !dst_ok || dst.family == AF_UNSPEC) {
 164                 fprintf(stderr, "Device and destination are required arguments.\n");
 165                 exit(-1);
 166         }
 167         req.ndm.ndm_family = dst.family;
 168         if (addattr_l(&req.n, sizeof(req), NDA_DST, &dst.data, dst.bytelen) < 0)
 169                 return -1;
 170
 171         if (lla && strcmp(lla, "null")) {
 172                 char llabuf[20];
 173                 int l;
 174
 175                 l = ll_addr_a2n(llabuf, sizeof(llabuf), lla);
 176                 if (l < 0)
 177                         return -1;
 178
 179                 if (addattr_l(&req.n, sizeof(req), NDA_LLADDR, llabuf, l) < 0)
 180                         return -1;
 181         }
 182
 183         ll_init_map(&rth);
 184
 185         if (dev) {
 186                 req.ndm.ndm_ifindex = ll_name_to_index(dev);
 187                 if (!req.ndm.ndm_ifindex)
 188                         return nodev(dev);
 189         }
 190
 191         if (rtnl_talk(&rth, &req.n, NULL) < 0)
 192                 exit(2);
 193
 194         return 0;
 195 }
 196
 197 static void print_cacheinfo(const struct nda_cacheinfo *ci)
 198 {
 199         static int hz;
 200
 201         if (!hz)
 202                 hz = get_user_hz();
 203
 204         if (ci->ndm_refcnt)
 205                 print_uint(PRINT_ANY, "refcnt",
 206                                 " ref %u", ci->ndm_refcnt);
 207
 208         print_uint(PRINT_ANY, "used", " used %u", ci->ndm_used / hz);
 209         print_uint(PRINT_ANY, "confirmed", "/%u", ci->ndm_confirmed / hz);
 210         print_uint(PRINT_ANY, "updated", "/%u", ci->ndm_updated / hz);
 211 }
 212
 213 static void print_neigh_state(unsigned int nud)
 214 {
 215
 216         open_json_array(PRINT_JSON,
 217                         is_json_context() ?  "state" : "");
 218
 219 #define PRINT_FLAG(f)                                           \
 220         if (nud & NUD_##f) {                                    \
 221                 nud &= ~NUD_##f;                                \
 222                 print_string(PRINT_ANY, NULL, " %s", #f);       \
 223         }
 224
 225         PRINT_FLAG(INCOMPLETE);
 226         PRINT_FLAG(REACHABLE);
 227         PRINT_FLAG(STALE);
 228         PRINT_FLAG(DELAY);
 229         PRINT_FLAG(PROBE);
 230         PRINT_FLAG(FAILED);
 231         PRINT_FLAG(NOARP);
 232         PRINT_FLAG(PERMANENT);
 233 #undef PRINT_FLAG
 234
 235         close_json_array(PRINT_JSON, NULL);
 236 }
 237
 238 int print_neigh(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
 239 {
 240         FILE *fp = (FILE *)arg;
 241         struct ndmsg *r = NLMSG_DATA(n);
 242         int len = n->nlmsg_len;
 243         struct rtattr *tb[NDA_MAX+1];
 244         static int logit = 1;
 245
 246         if (n->nlmsg_type != RTM_NEWNEIGH && n->nlmsg_type != RTM_DELNEIGH &&
 247             n->nlmsg_type != RTM_GETNEIGH) {
 248                 fprintf(stderr, "Not RTM_NEWNEIGH: %08x %08x %08x\n",
 249                         n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
 250
 251                 return 0;
 252         }
 253         len -= NLMSG_LENGTH(sizeof(*r));
 254         if (len < 0) {
 255                 fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
 256                 return -1;
 257         }
 258
 259         if (filter.flushb && n->nlmsg_type != RTM_NEWNEIGH)
 260                 return 0;
 261
 262         if (filter.family && filter.family != r->ndm_family)
 263                 return 0;
 264         if (filter.index && filter.index != r->ndm_ifindex)
 265                 return 0;
 266         if (!(filter.state&r->ndm_state) &&
 267             !(r->ndm_flags & NTF_PROXY) &&
 268             !(r->ndm_flags & NTF_EXT_LEARNED) &&
 269             (r->ndm_state || !(filter.state&0x100)) &&
 270             (r->ndm_family != AF_DECnet))
 271                 return 0;
 272
 273         if (filter.master && !(n->nlmsg_flags & NLM_F_DUMP_FILTERED)) {
 274                 if (logit) {
 275                         logit = 0;
 276                         fprintf(fp,
 277                                 "\nWARNING: Kernel does not support filtering by master device\n\n");
 278                 }
 279         }
 280
 281         parse_rtattr(tb, NDA_MAX, NDA_RTA(r), n->nlmsg_len - NLMSG_LENGTH(sizeof(*r)));
 282
 283         if (inet_addr_match_rta(&filter.pfx, tb[NDA_DST]))
 284                 return 0;
 285
 286         if (filter.unused_only && tb[NDA_CACHEINFO]) {
 287                 struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
 288
 289                 if (ci->ndm_refcnt)
 290                         return 0;
 291         }
 292
 293         if (filter.flushb) {
 294                 struct nlmsghdr *fn;
 295
 296                 if (NLMSG_ALIGN(filter.flushp) + n->nlmsg_len > filter.flushe) {
 297                         if (flush_update())
 298                                 return -1;
 299                 }
 300                 fn = (struct nlmsghdr *)(filter.flushb + NLMSG_ALIGN(filter.flushp));
 301                 memcpy(fn, n, n->nlmsg_len);
 302                 fn->nlmsg_type = RTM_DELNEIGH;
 303                 fn->nlmsg_flags = NLM_F_REQUEST;
 304                 fn->nlmsg_seq = ++rth.seq;
 305                 filter.flushp = (((char *)fn) + n->nlmsg_len) - filter.flushb;
 306                 filter.flushed++;
 307                 if (show_stats < 2)
 308                         return 0;
 309         }
 310
 311         open_json_object(NULL);
 312         if (n->nlmsg_type == RTM_DELNEIGH)
 313                 print_bool(PRINT_ANY, "deleted", "Deleted ", true);
 314         else if (n->nlmsg_type == RTM_GETNEIGH)
 315                 print_null(PRINT_ANY, "miss", "%s ", "miss");
 316
 317         if (tb[NDA_DST]) {
 318                 const char *dst;
 319
 320                 dst = format_host_rta(r->ndm_family, tb[NDA_DST]);
 321                 print_color_string(PRINT_ANY,
 322                                    ifa_family_color(r->ndm_family),
 323                                    "dst", "%s ", dst);
 324         }
 325
 326         if (!filter.index && r->ndm_ifindex) {
 327                 if (!is_json_context())
 328                         fprintf(fp, "dev ");
 329
 330                 print_color_string(PRINT_ANY, COLOR_IFNAME,
 331                                    "dev", "%s ",
 332                                    ll_index_to_name(r->ndm_ifindex));
 333         }
 334
 335         if (tb[NDA_LLADDR]) {
 336                 const char *lladdr;
 337                 SPRINT_BUF(b1);
 338
 339                 lladdr = ll_addr_n2a(RTA_DATA(tb[NDA_LLADDR]),
 340                                      RTA_PAYLOAD(tb[NDA_LLADDR]),
 341                                      ll_index_to_type(r->ndm_ifindex),
 342                                      b1, sizeof(b1));
 343
 344                 if (!is_json_context())
 345                         fprintf(fp, "lladdr ");
 346
 347                 print_color_string(PRINT_ANY, COLOR_MAC,
 348                                    "lladdr", "%s", lladdr);
 349         }
 350
 351         if (r->ndm_flags & NTF_ROUTER)
 352                 print_null(PRINT_ANY, "router", " %s", "router");
 353
 354         if (r->ndm_flags & NTF_PROXY)
 355                 print_null(PRINT_ANY, "proxy", " %s", "proxy");
 356
 357         if (show_stats) {
 358                 if (tb[NDA_CACHEINFO])
 359                         print_cacheinfo(RTA_DATA(tb[NDA_CACHEINFO]));
 360
 361                 if (tb[NDA_PROBES])
 362                         print_uint(PRINT_ANY, "probes", " probes %u",
 363                                    rta_getattr_u32(tb[NDA_PROBES]));
 364         }
 365
 366         if (r->ndm_state)
 367                 print_neigh_state(r->ndm_state);
 368
 369         print_string(PRINT_FP, NULL, "\n", "");
 370         close_json_object();
 371         fflush(stdout);
 372
 373         return 0;
 374 }
 375
 376 void ipneigh_reset_filter(int ifindex)
 377 {
 378         memset(&filter, 0, sizeof(filter));
 379         filter.state = ~0;
 380         filter.index = ifindex;
 381 }
 382
 383 static int do_show_or_flush(int argc, char **argv, int flush)
 384 {
 385         struct {
 386                 struct nlmsghdr n;
 387                 struct ndmsg            ndm;
 388                 char                    buf[256];
 389         } req = {
 390                 .n.nlmsg_type = RTM_GETNEIGH,
 391                 .n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),
 392         };
 393         char *filter_dev = NULL;
 394         int state_given = 0;
 395
 396         ipneigh_reset_filter(0);
 397
 398         if (!filter.family)
 399                 filter.family = preferred_family;
 400
 401         if (flush) {
 402                 if (argc <= 0) {
 403                         fprintf(stderr, "Flush requires arguments.\n");
 404                         return -1;
 405                 }
 406                 filter.state = ~(NUD_PERMANENT|NUD_NOARP);
 407         } else
 408                 filter.state = 0xFF & ~NUD_NOARP;
 409
 410         while (argc > 0) {
 411                 if (strcmp(*argv, "dev") == 0) {
 412                         NEXT_ARG();
 413                         if (filter_dev)
 414                                 duparg("dev", *argv);
 415                         filter_dev = *argv;
 416                 } else if (strcmp(*argv, "master") == 0) {
 417                         int ifindex;
 418
 419                         NEXT_ARG();
 420                         ifindex = ll_name_to_index(*argv);
 421                         if (!ifindex)
 422                                 invarg("Device does not exist\n", *argv);
 423                         addattr32(&req.n, sizeof(req), NDA_MASTER, ifindex);
 424                         filter.master = ifindex;
 425                 } else if (strcmp(*argv, "vrf") == 0) {
 426                         int ifindex;
 427
 428                         NEXT_ARG();
 429                         ifindex = ll_name_to_index(*argv);
 430                         if (!ifindex)
 431                                 invarg("Not a valid VRF name\n", *argv);
 432                         if (!name_is_vrf(*argv))
 433                                 invarg("Not a valid VRF name\n", *argv);
 434                         addattr32(&req.n, sizeof(req), NDA_MASTER, ifindex);
 435                         filter.master = ifindex;
 436                 } else if (strcmp(*argv, "unused") == 0) {
 437                         filter.unused_only = 1;
 438                 } else if (strcmp(*argv, "nud") == 0) {
 439                         unsigned int state;
 440
 441                         NEXT_ARG();
 442                         if (!state_given) {
 443                                 state_given = 1;
 444                                 filter.state = 0;
 445                         }
 446                         if (nud_state_a2n(&state, *argv)) {
 447                                 if (strcmp(*argv, "all") != 0)
 448                                         invarg("nud state is bad", *argv);
 449                                 state = ~0;
 450                                 if (flush)
 451                                         state &= ~NUD_NOARP;
 452                         }
 453                         if (state == 0)
 454                                 state = 0x100;
 455                         filter.state |= state;
 456                 } else if (strcmp(*argv, "proxy") == 0)
 457                         req.ndm.ndm_flags = NTF_PROXY;
 458                 else {
 459                         if (strcmp(*argv, "to") == 0) {
 460                                 NEXT_ARG();
 461                         }
 462                         if (matches(*argv, "help") == 0)
 463                                 usage();
 464                         if (get_prefix(&filter.pfx, *argv, filter.family))
 465                                 invarg("to value is invalid\n", *argv);
 466                         if (filter.family == AF_UNSPEC)
 467                                 filter.family = filter.pfx.family;
 468                 }
 469                 argc--; argv++;
 470         }
 471
 472         ll_init_map(&rth);
 473
 474         if (filter_dev) {
 475                 filter.index = ll_name_to_index(filter_dev);
 476                 if (!filter.index)
 477                         return nodev(filter_dev);
 478                 addattr32(&req.n, sizeof(req), NDA_IFINDEX, filter.index);
 479         }
 480
 481         req.ndm.ndm_family = filter.family;
 482
 483         if (flush) {
 484                 int round = 0;
 485                 char flushb[4096-512];
 486
 487                 filter.flushb = flushb;
 488                 filter.flushp = 0;
 489                 filter.flushe = sizeof(flushb);
 490
 491                 while (round < MAX_ROUNDS) {
 492                         if (rtnl_dump_request_n(&rth, &req.n) < 0) {
 493                                 perror("Cannot send dump request");
 494                                 exit(1);
 495                         }
 496                         filter.flushed = 0;
 497                         if (rtnl_dump_filter(&rth, print_neigh, stdout) < 0) {
 498                                 fprintf(stderr, "Flush terminated\n");
 499                                 exit(1);
 500                         }
 501                         if (filter.flushed == 0) {
 502                                 if (show_stats) {
 503                                         if (round == 0)
 504                                                 printf("Nothing to flush.\n");
 505                                         else
 506                                                 printf("*** Flush is complete after %d round%s ***\n", round, round > 1?"s":"");
 507                                 }
 508                                 fflush(stdout);
 509                                 return 0;
 510                         }
 511                         round++;
 512                         if (flush_update() < 0)
 513                                 exit(1);
 514                         if (show_stats) {
 515                                 printf("\n*** Round %d, deleting %d entries ***\n", round, filter.flushed);
 516                                 fflush(stdout);
 517                         }
 518                         filter.state &= ~NUD_FAILED;
 519                 }
 520                 printf("*** Flush not complete bailing out after %d rounds\n",
 521                         MAX_ROUNDS);
 522                 return 1;
 523         }
 524
 525         if (rtnl_dump_request_n(&rth, &req.n) < 0) {
 526                 perror("Cannot send dump request");
 527                 exit(1);
 528         }
 529
 530         new_json_obj(json);
 531         if (rtnl_dump_filter(&rth, print_neigh, stdout) < 0) {
 532                 fprintf(stderr, "Dump terminated\n");
 533                 exit(1);
 534         }
 535         delete_json_obj();
 536
 537         return 0;
 538 }
 539
 540 int do_ipneigh(int argc, char **argv)
 541 {
 542         if (argc > 0) {
 543                 if (matches(*argv, "add") == 0)
 544                         return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_EXCL, argc-1, argv+1);
 545                 if (matches(*argv, "change") == 0 ||
 546                     strcmp(*argv, "chg") == 0)
 547                         return ipneigh_modify(RTM_NEWNEIGH, NLM_F_REPLACE, argc-1, argv+1);
 548                 if (matches(*argv, "replace") == 0)
 549                         return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_REPLACE, argc-1, argv+1);
 550                 if (matches(*argv, "delete") == 0)
 551                         return ipneigh_modify(RTM_DELNEIGH, 0, argc-1, argv+1);
 552                 if (matches(*argv, "get") == 0) {
 553                         fprintf(stderr, "Sorry, \"neigh get\" is not implemented :-(\n");
 554                         return -1;
 555                 }
 556                 if (matches(*argv, "show") == 0 ||
 557                     matches(*argv, "lst") == 0 ||
 558                     matches(*argv, "list") == 0)
 559                         return do_show_or_flush(argc-1, argv+1, 0);
 560                 if (matches(*argv, "flush") == 0)
 561                         return do_show_or_flush(argc-1, argv+1, 1);
 562                 if (matches(*argv, "help") == 0)
 563                         usage();
 564         } else
 565                 return do_show_or_flush(0, NULL, 0);
 566
 567         fprintf(stderr, "Command \"%s\" is unknown, try \"ip neigh help\".\n", *argv);
 568         exit(-1);
 569 }