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