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 <syslog.h>
  17 #include <fcntl.h>
  18 #include <string.h>
  19 #include <sys/time.h>
  20 #include <sys/socket.h>
  21 #include <netinet/in.h>
  22 #include <netinet/ip.h>
  23
  24 #include "rt_names.h"
  25 #include "utils.h"
  26 #include "ip_common.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
 194 int print_neigh(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
 195 {
 196         FILE *fp = (FILE *)arg;
 197         struct ndmsg *r = NLMSG_DATA(n);
 198         int len = n->nlmsg_len;
 199         struct rtattr *tb[NDA_MAX+1];
 200         static int logit = 1;
 201
 202         if (n->nlmsg_type != RTM_NEWNEIGH && n->nlmsg_type != RTM_DELNEIGH &&
 203             n->nlmsg_type != RTM_GETNEIGH) {
 204                 fprintf(stderr, "Not RTM_NEWNEIGH: %08x %08x %08x\n",
 205                         n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
 206
 207                 return 0;
 208         }
 209         len -= NLMSG_LENGTH(sizeof(*r));
 210         if (len < 0) {
 211                 fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
 212                 return -1;
 213         }
 214
 215         if (filter.flushb && n->nlmsg_type != RTM_NEWNEIGH)
 216                 return 0;
 217
 218         if (filter.family && filter.family != r->ndm_family)
 219                 return 0;
 220         if (filter.index && filter.index != r->ndm_ifindex)
 221                 return 0;
 222         if (!(filter.state&r->ndm_state) &&
 223             !(r->ndm_flags & NTF_PROXY) &&
 224             (r->ndm_state || !(filter.state&0x100)) &&
 225              (r->ndm_family != AF_DECnet))
 226                 return 0;
 227
 228         if (filter.master && !(n->nlmsg_flags & NLM_F_DUMP_FILTERED)) {
 229                 if (logit) {
 230                         logit = 0;
 231                         fprintf(fp,
 232                                 "\nWARNING: Kernel does not support filtering by master device\n\n");
 233                 }
 234         }
 235
 236         parse_rtattr(tb, NDA_MAX, NDA_RTA(r), n->nlmsg_len - NLMSG_LENGTH(sizeof(*r)));
 237
 238         if (tb[NDA_DST]) {
 239                 if (filter.pfx.family) {
 240                         inet_prefix dst = { .family = r->ndm_family };
 241
 242                         memcpy(&dst.data, RTA_DATA(tb[NDA_DST]), RTA_PAYLOAD(tb[NDA_DST]));
 243                         if (inet_addr_match(&dst, &filter.pfx, filter.pfx.bitlen))
 244                                 return 0;
 245                 }
 246         }
 247         if (filter.unused_only && tb[NDA_CACHEINFO]) {
 248                 struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
 249
 250                 if (ci->ndm_refcnt)
 251                         return 0;
 252         }
 253
 254         if (filter.flushb) {
 255                 struct nlmsghdr *fn;
 256
 257                 if (NLMSG_ALIGN(filter.flushp) + n->nlmsg_len > filter.flushe) {
 258                         if (flush_update())
 259                                 return -1;
 260                 }
 261                 fn = (struct nlmsghdr *)(filter.flushb + NLMSG_ALIGN(filter.flushp));
 262                 memcpy(fn, n, n->nlmsg_len);
 263                 fn->nlmsg_type = RTM_DELNEIGH;
 264                 fn->nlmsg_flags = NLM_F_REQUEST;
 265                 fn->nlmsg_seq = ++rth.seq;
 266                 filter.flushp = (((char *)fn) + n->nlmsg_len) - filter.flushb;
 267                 filter.flushed++;
 268                 if (show_stats < 2)
 269                         return 0;
 270         }
 271
 272         if (n->nlmsg_type == RTM_DELNEIGH)
 273                 fprintf(fp, "Deleted ");
 274         else if (n->nlmsg_type == RTM_GETNEIGH)
 275                 fprintf(fp, "miss ");
 276         if (tb[NDA_DST]) {
 277                 fprintf(fp, "%s ",
 278                         format_host_rta(r->ndm_family, tb[NDA_DST]));
 279         }
 280         if (!filter.index && r->ndm_ifindex)
 281                 fprintf(fp, "dev %s ", ll_index_to_name(r->ndm_ifindex));
 282         if (tb[NDA_LLADDR]) {
 283                 SPRINT_BUF(b1);
 284                 fprintf(fp, "lladdr %s", ll_addr_n2a(RTA_DATA(tb[NDA_LLADDR]),
 285                                               RTA_PAYLOAD(tb[NDA_LLADDR]),
 286                                               ll_index_to_type(r->ndm_ifindex),
 287                                               b1, sizeof(b1)));
 288         }
 289         if (r->ndm_flags & NTF_ROUTER) {
 290                 fprintf(fp, " router");
 291         }
 292         if (r->ndm_flags & NTF_PROXY) {
 293                 fprintf(fp, " proxy");
 294         }
 295         if (tb[NDA_CACHEINFO] && show_stats) {
 296                 struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
 297                 int hz = get_user_hz();
 298
 299                 if (ci->ndm_refcnt)
 300                         printf(" ref %d", ci->ndm_refcnt);
 301                 fprintf(fp, " used %d/%d/%d", ci->ndm_used/hz,
 302                        ci->ndm_confirmed/hz, ci->ndm_updated/hz);
 303         }
 304
 305         if (tb[NDA_PROBES] && show_stats) {
 306                 __u32 p = rta_getattr_u32(tb[NDA_PROBES]);
 307
 308                 fprintf(fp, " probes %u", p);
 309         }
 310
 311         if (r->ndm_state) {
 312                 int nud = r->ndm_state;
 313
 314                 fprintf(fp, " ");
 315
 316 #define PRINT_FLAG(f) if (nud & NUD_##f) { \
 317         nud &= ~NUD_##f; fprintf(fp, #f "%s", nud ? "," : ""); }
 318                 PRINT_FLAG(INCOMPLETE);
 319                 PRINT_FLAG(REACHABLE);
 320                 PRINT_FLAG(STALE);
 321                 PRINT_FLAG(DELAY);
 322                 PRINT_FLAG(PROBE);
 323                 PRINT_FLAG(FAILED);
 324                 PRINT_FLAG(NOARP);
 325                 PRINT_FLAG(PERMANENT);
 326 #undef PRINT_FLAG
 327         }
 328         fprintf(fp, "\n");
 329
 330         fflush(fp);
 331         return 0;
 332 }
 333
 334 void ipneigh_reset_filter(int ifindex)
 335 {
 336         memset(&filter, 0, sizeof(filter));
 337         filter.state = ~0;
 338         filter.index = ifindex;
 339 }
 340
 341 static int do_show_or_flush(int argc, char **argv, int flush)
 342 {
 343         struct {
 344                 struct nlmsghdr n;
 345                 struct ndmsg            ndm;
 346                 char                    buf[256];
 347         } req = {
 348                 .n.nlmsg_type = RTM_GETNEIGH,
 349                 .n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),
 350         };
 351         char *filter_dev = NULL;
 352         int state_given = 0;
 353
 354         ipneigh_reset_filter(0);
 355
 356         if (!filter.family)
 357                 filter.family = preferred_family;
 358
 359         if (flush) {
 360                 if (argc <= 0) {
 361                         fprintf(stderr, "Flush requires arguments.\n");
 362                         return -1;
 363                 }
 364                 filter.state = ~(NUD_PERMANENT|NUD_NOARP);
 365         } else
 366                 filter.state = 0xFF & ~NUD_NOARP;
 367
 368         while (argc > 0) {
 369                 if (strcmp(*argv, "dev") == 0) {
 370                         NEXT_ARG();
 371                         if (filter_dev)
 372                                 duparg("dev", *argv);
 373                         filter_dev = *argv;
 374                 } else if (strcmp(*argv, "master") == 0) {
 375                         int ifindex;
 376
 377                         NEXT_ARG();
 378                         ifindex = ll_name_to_index(*argv);
 379                         if (!ifindex)
 380                                 invarg("Device does not exist\n", *argv);
 381                         addattr32(&req.n, sizeof(req), NDA_MASTER, ifindex);
 382                         filter.master = ifindex;
 383                 } else if (strcmp(*argv, "vrf") == 0) {
 384                         int ifindex;
 385
 386                         NEXT_ARG();
 387                         ifindex = ll_name_to_index(*argv);
 388                         if (!ifindex)
 389                                 invarg("Not a valid VRF name\n", *argv);
 390                         if (!name_is_vrf(*argv))
 391                                 invarg("Not a valid VRF name\n", *argv);
 392                         addattr32(&req.n, sizeof(req), NDA_MASTER, ifindex);
 393                         filter.master = ifindex;
 394                 } else if (strcmp(*argv, "unused") == 0) {
 395                         filter.unused_only = 1;
 396                 } else if (strcmp(*argv, "nud") == 0) {
 397                         unsigned int state;
 398
 399                         NEXT_ARG();
 400                         if (!state_given) {
 401                                 state_given = 1;
 402                                 filter.state = 0;
 403                         }
 404                         if (nud_state_a2n(&state, *argv)) {
 405                                 if (strcmp(*argv, "all") != 0)
 406                                         invarg("nud state is bad", *argv);
 407                                 state = ~0;
 408                                 if (flush)
 409                                         state &= ~NUD_NOARP;
 410                         }
 411                         if (state == 0)
 412                                 state = 0x100;
 413                         filter.state |= state;
 414                 } else if (strcmp(*argv, "proxy") == 0)
 415                         req.ndm.ndm_flags = NTF_PROXY;
 416                 else {
 417                         if (strcmp(*argv, "to") == 0) {
 418                                 NEXT_ARG();
 419                         }
 420                         if (matches(*argv, "help") == 0)
 421                                 usage();
 422                         get_prefix(&filter.pfx, *argv, filter.family);
 423                         if (filter.family == AF_UNSPEC)
 424                                 filter.family = filter.pfx.family;
 425                 }
 426                 argc--; argv++;
 427         }
 428
 429         ll_init_map(&rth);
 430
 431         if (filter_dev) {
 432                 if ((filter.index = ll_name_to_index(filter_dev)) == 0) {
 433                         fprintf(stderr, "Cannot find device \"%s\"\n", filter_dev);
 434                         return -1;
 435                 }
 436                 addattr32(&req.n, sizeof(req), NDA_IFINDEX, filter.index);
 437         }
 438
 439         req.ndm.ndm_family = filter.family;
 440
 441         if (flush) {
 442                 int round = 0;
 443                 char flushb[4096-512];
 444
 445                 filter.flushb = flushb;
 446                 filter.flushp = 0;
 447                 filter.flushe = sizeof(flushb);
 448
 449                 while (round < MAX_ROUNDS) {
 450                         if (rtnl_dump_request_n(&rth, &req.n) < 0) {
 451                                 perror("Cannot send dump request");
 452                                 exit(1);
 453                         }
 454                         filter.flushed = 0;
 455                         if (rtnl_dump_filter(&rth, print_neigh, stdout) < 0) {
 456                                 fprintf(stderr, "Flush terminated\n");
 457                                 exit(1);
 458                         }
 459                         if (filter.flushed == 0) {
 460                                 if (show_stats) {
 461                                         if (round == 0)
 462                                                 printf("Nothing to flush.\n");
 463                                         else
 464                                                 printf("*** Flush is complete after %d round%s ***\n", round, round > 1?"s":"");
 465                                 }
 466                                 fflush(stdout);
 467                                 return 0;
 468                         }
 469                         round++;
 470                         if (flush_update() < 0)
 471                                 exit(1);
 472                         if (show_stats) {
 473                                 printf("\n*** Round %d, deleting %d entries ***\n", round, filter.flushed);
 474                                 fflush(stdout);
 475                         }
 476                         filter.state &= ~NUD_FAILED;
 477                 }
 478                 printf("*** Flush not complete bailing out after %d rounds\n",
 479                         MAX_ROUNDS);
 480                 return 1;
 481         }
 482
 483         if (rtnl_dump_request_n(&rth, &req.n) < 0) {
 484                 perror("Cannot send dump request");
 485                 exit(1);
 486         }
 487
 488         if (rtnl_dump_filter(&rth, print_neigh, stdout) < 0) {
 489                 fprintf(stderr, "Dump terminated\n");
 490                 exit(1);
 491         }
 492
 493         return 0;
 494 }
 495
 496 int do_ipneigh(int argc, char **argv)
 497 {
 498         if (argc > 0) {
 499                 if (matches(*argv, "add") == 0)
 500                         return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_EXCL, argc-1, argv+1);
 501                 if (matches(*argv, "change") == 0 ||
 502                     strcmp(*argv, "chg") == 0)
 503                         return ipneigh_modify(RTM_NEWNEIGH, NLM_F_REPLACE, argc-1, argv+1);
 504                 if (matches(*argv, "replace") == 0)
 505                         return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_REPLACE, argc-1, argv+1);
 506                 if (matches(*argv, "delete") == 0)
 507                         return ipneigh_modify(RTM_DELNEIGH, 0, argc-1, argv+1);
 508                 if (matches(*argv, "get") == 0) {
 509                         fprintf(stderr, "Sorry, \"neigh get\" is not implemented :-(\n");
 510                         return -1;
 511                 }
 512                 if (matches(*argv, "show") == 0 ||
 513                     matches(*argv, "lst") == 0 ||
 514                     matches(*argv, "list") == 0)
 515                         return do_show_or_flush(argc-1, argv+1, 0);
 516                 if (matches(*argv, "flush") == 0)
 517                         return do_show_or_flush(argc-1, argv+1, 1);
 518                 if (matches(*argv, "help") == 0)
 519                         usage();
 520         } else
 521                 return do_show_or_flush(0, NULL, 0);
 522
 523         fprintf(stderr, "Command \"%s\" is unknown, try \"ip neigh help\".\n", *argv);
 524         exit(-1);
 525 }