networking/libiproute/ipneigh.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   4  *
   5  * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
   6  *
   7  * Ported to Busybox by:  Curt Brune <curt@cumulusnetworks.com>
   8  */
   9
  10 #include "ip_common.h"  /* #include "libbb.h" is inside */
  11 #include "common_bufsiz.h"
  12 #include "rt_names.h"
  13 #include "utils.h"
  14 #include <linux/neighbour.h>
  15 #include <net/if_arp.h>
  16
  17 //static int xshow_stats = 3;
  18 enum { xshow_stats = 3 };
  19
  20 static inline uint32_t rta_getattr_u32(const struct rtattr *rta)
  21 {
  22         return *(uint32_t *)RTA_DATA(rta);
  23 }
  24
  25 #ifndef RTAX_RTTVAR
  26 #define RTAX_RTTVAR RTAX_HOPS
  27 #endif
  28
  29
  30 struct filter_t {
  31         int family;
  32         int index;
  33         int state;
  34         int unused_only;
  35         inet_prefix pfx;
  36         int flushed;
  37         char *flushb;
  38         int flushp;
  39         int flushe;
  40         struct rtnl_handle *rth;
  41 } FIX_ALIASING;
  42 typedef struct filter_t filter_t;
  43
  44 #define G_filter (*(filter_t*)bb_common_bufsiz1)
  45 #define INIT_G() do { setup_common_bufsiz(); } while (0)
  46
  47 static int flush_update(void)
  48 {
  49         if (rtnl_send(G_filter.rth, G_filter.flushb, G_filter.flushp) < 0) {
  50                 bb_perror_msg("can't send flush request");
  51                 return -1;
  52         }
  53         G_filter.flushp = 0;
  54         return 0;
  55 }
  56
  57 static unsigned nud_state_a2n(char *arg)
  58 {
  59         static const char keywords[] ALIGN1 =
  60                 /* "ip neigh show/flush" parameters: */
  61                 "permanent\0" "reachable\0"   "noarp\0"  "none\0"
  62                 "stale\0"     "incomplete\0"  "delay\0"  "probe\0"
  63                 "failed\0"
  64                 ;
  65         static uint8_t nuds[] ALIGN1 = {
  66                 NUD_PERMANENT,NUD_REACHABLE, NUD_NOARP,NUD_NONE,
  67                 NUD_STALE,    NUD_INCOMPLETE,NUD_DELAY,NUD_PROBE,
  68                 NUD_FAILED
  69         };
  70         int id;
  71
  72         BUILD_BUG_ON(
  73                 (NUD_PERMANENT|NUD_REACHABLE| NUD_NOARP|NUD_NONE|
  74                 NUD_STALE|    NUD_INCOMPLETE|NUD_DELAY|NUD_PROBE|
  75                 NUD_FAILED) > 0xff
  76         );
  77
  78         id = index_in_substrings(keywords, arg);
  79         if (id < 0)
  80                 bb_error_msg_and_die(bb_msg_invalid_arg_to, arg, "nud state");
  81         return nuds[id];
  82 }
  83
  84 #ifndef NDA_RTA
  85 #define NDA_RTA(r) \
  86         ((struct rtattr*)(((char*)(r)) + NLMSG_ALIGN(sizeof(struct ndmsg))))
  87 #endif
  88
  89
  90 static int FAST_FUNC print_neigh(const struct sockaddr_nl *who UNUSED_PARAM,
  91                                  struct nlmsghdr *n, void *arg UNUSED_PARAM)
  92 {
  93         struct ndmsg *r = NLMSG_DATA(n);
  94         int len = n->nlmsg_len;
  95         struct rtattr *tb[NDA_MAX+1];
  96
  97         if (n->nlmsg_type != RTM_NEWNEIGH && n->nlmsg_type != RTM_DELNEIGH) {
  98                 bb_error_msg_and_die("not RTM_NEWNEIGH: %08x %08x %08x",
  99                                      n->nlmsg_len, n->nlmsg_type,
 100                                      n->nlmsg_flags);
 101         }
 102         len -= NLMSG_LENGTH(sizeof(*r));
 103         if (len < 0) {
 104                 bb_error_msg_and_die("BUG: wrong nlmsg len %d", len);
 105         }
 106
 107         if (G_filter.flushb && n->nlmsg_type != RTM_NEWNEIGH)
 108                 return 0;
 109
 110         if (G_filter.family && G_filter.family != r->ndm_family)
 111                 return 0;
 112         if (G_filter.index && G_filter.index != r->ndm_ifindex)
 113                 return 0;
 114         if (!(G_filter.state&r->ndm_state) &&
 115             !(r->ndm_flags & NTF_PROXY) &&
 116             (r->ndm_state || !(G_filter.state & 0x100)) &&
 117             (r->ndm_family != AF_DECnet))
 118                 return 0;
 119
 120         parse_rtattr(tb, NDA_MAX, NDA_RTA(r), n->nlmsg_len - NLMSG_LENGTH(sizeof(*r)));
 121
 122         if (tb[NDA_DST]) {
 123                 if (G_filter.pfx.family) {
 124                         inet_prefix dst;
 125                         memset(&dst, 0, sizeof(dst));
 126                         dst.family = r->ndm_family;
 127                         memcpy(&dst.data, RTA_DATA(tb[NDA_DST]), RTA_PAYLOAD(tb[NDA_DST]));
 128                         if (inet_addr_match(&dst, &G_filter.pfx, G_filter.pfx.bitlen))
 129                                 return 0;
 130                 }
 131         }
 132         if (G_filter.unused_only && tb[NDA_CACHEINFO]) {
 133                 struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
 134                 if (ci->ndm_refcnt)
 135                         return 0;
 136         }
 137
 138         if (G_filter.flushb) {
 139                 struct nlmsghdr *fn;
 140                 if (NLMSG_ALIGN(G_filter.flushp) + n->nlmsg_len > G_filter.flushe) {
 141                         if (flush_update())
 142                                 return -1;
 143                 }
 144                 fn = (struct nlmsghdr*)(G_filter.flushb + NLMSG_ALIGN(G_filter.flushp));
 145                 memcpy(fn, n, n->nlmsg_len);
 146                 fn->nlmsg_type = RTM_DELNEIGH;
 147                 fn->nlmsg_flags = NLM_F_REQUEST;
 148                 fn->nlmsg_seq = ++(G_filter.rth->seq);
 149                 G_filter.flushp = (((char*)fn) + n->nlmsg_len) - G_filter.flushb;
 150                 G_filter.flushed++;
 151                 if (xshow_stats < 2)
 152                         return 0;
 153         }
 154
 155         if (tb[NDA_DST]) {
 156                 printf("%s ",
 157                        format_host(r->ndm_family,
 158                                    RTA_PAYLOAD(tb[NDA_DST]),
 159                                    RTA_DATA(tb[NDA_DST]))
 160                 );
 161         }
 162         if (!G_filter.index && r->ndm_ifindex)
 163                 printf("dev %s ", ll_index_to_name(r->ndm_ifindex));
 164         if (tb[NDA_LLADDR]) {
 165                 SPRINT_BUF(b1);
 166                 printf("lladdr %s", ll_addr_n2a(RTA_DATA(tb[NDA_LLADDR]),
 167                                                 RTA_PAYLOAD(tb[NDA_LLADDR]),
 168                                                 ARPHRD_ETHER,
 169                                                 b1, sizeof(b1)));
 170         }
 171         if (r->ndm_flags & NTF_ROUTER) {
 172                 printf(" router");
 173         }
 174         if (r->ndm_flags & NTF_PROXY) {
 175                 printf(" proxy");
 176         }
 177         if (tb[NDA_CACHEINFO] && xshow_stats) {
 178                 struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
 179                 int hz = get_hz();
 180
 181                 if (ci->ndm_refcnt)
 182                         printf(" ref %d", ci->ndm_refcnt);
 183                 printf(" used %d/%d/%d", ci->ndm_used/hz,
 184                        ci->ndm_confirmed/hz, ci->ndm_updated/hz);
 185         }
 186
 187         if (tb[NDA_PROBES] && xshow_stats) {
 188                 uint32_t p = rta_getattr_u32(tb[NDA_PROBES]);
 189                 printf(" probes %u", p);
 190         }
 191
 192         /*if (r->ndm_state)*/ {
 193                 int nud = r->ndm_state;
 194                 char c = ' ';
 195 #define PRINT_FLAG(f) \
 196                 if (nud & NUD_##f) { \
 197                         printf("%c"#f, c); \
 198                         c = ','; \
 199                 }
 200                 PRINT_FLAG(INCOMPLETE);
 201                 PRINT_FLAG(REACHABLE);
 202                 PRINT_FLAG(STALE);
 203                 PRINT_FLAG(DELAY);
 204                 PRINT_FLAG(PROBE);
 205                 PRINT_FLAG(FAILED);
 206                 PRINT_FLAG(NOARP);
 207                 PRINT_FLAG(PERMANENT);
 208 #undef PRINT_FLAG
 209         }
 210         bb_putchar('\n');
 211
 212         return 0;
 213 }
 214
 215 static void ipneigh_reset_filter(void)
 216 {
 217         memset(&G_filter, 0, sizeof(G_filter));
 218         G_filter.state = ~0;
 219 }
 220
 221 #define MAX_ROUNDS      10
 222 /* Return value becomes exitcode. It's okay to not return at all */
 223 static int FAST_FUNC ipneigh_list_or_flush(char **argv, int flush)
 224 {
 225         static const char keywords[] ALIGN1 =
 226                 /* "ip neigh show/flush" parameters: */
 227                 "to\0" "dev\0"   "nud\0";
 228         enum {
 229                 KW_to, KW_dev, KW_nud,
 230         };
 231         struct rtnl_handle rth;
 232         struct ndmsg ndm = { 0 };
 233         char *filter_dev = NULL;
 234         int state_given = 0;
 235         int arg;
 236
 237         ipneigh_reset_filter();
 238
 239         if (flush && !*argv)
 240                 bb_error_msg_and_die(bb_msg_requires_arg, "\"ip neigh flush\"");
 241
 242         if (!G_filter.family)
 243                 G_filter.family = preferred_family;
 244
 245         G_filter.state = (flush) ?
 246                 ~(NUD_PERMANENT|NUD_NOARP) : 0xFF & ~NUD_NOARP;
 247
 248         while (*argv) {
 249                 arg = index_in_substrings(keywords, *argv);
 250                 if (arg == KW_dev) {
 251                         NEXT_ARG();
 252                         filter_dev = *argv;
 253                 } else if (arg == KW_nud) {
 254                         unsigned state;
 255                         NEXT_ARG();
 256                         if (!state_given) {
 257                                 state_given = 1;
 258                                 G_filter.state = 0;
 259                         }
 260                         if (strcmp(*argv, "all") == 0) {
 261                                 state = ~0;
 262                                 if (flush)
 263                                         state &= ~NUD_NOARP;
 264                         } else {
 265                                 state = nud_state_a2n(*argv);
 266                         }
 267                         if (state == 0)
 268                                 state = 0x100;
 269                         G_filter.state |= state;
 270                 } else {
 271                         if (arg == KW_to) {
 272                                 NEXT_ARG();
 273                         }
 274                         get_prefix(&G_filter.pfx, *argv, G_filter.family);
 275                         if (G_filter.family == AF_UNSPEC)
 276                                 G_filter.family = G_filter.pfx.family;
 277                 }
 278                 argv++;
 279         }
 280
 281         xrtnl_open(&rth);
 282         ll_init_map(&rth);
 283
 284         if (filter_dev)  {
 285                 G_filter.index = xll_name_to_index(filter_dev);
 286                 if (G_filter.index == 0) {
 287                         bb_error_msg_and_die("can't find device '%s'", filter_dev);
 288                 }
 289         }
 290
 291         if (flush) {
 292                 int round = 0;
 293                 char flushb[4096-512];
 294                 G_filter.flushb = flushb;
 295                 G_filter.flushp = 0;
 296                 G_filter.flushe = sizeof(flushb);
 297                 G_filter.state &= ~NUD_FAILED;
 298                 G_filter.rth = &rth;
 299
 300                 while (round < MAX_ROUNDS) {
 301                         if (xrtnl_wilddump_request(&rth, G_filter.family, RTM_GETNEIGH) < 0) {
 302                                 bb_perror_msg_and_die("can't send dump request");
 303                         }
 304                         G_filter.flushed = 0;
 305                         if (xrtnl_dump_filter(&rth, print_neigh, NULL) < 0) {
 306                                 bb_perror_msg_and_die("flush terminated");
 307                         }
 308                         if (G_filter.flushed == 0) {
 309                                 if (round == 0)
 310                                         puts("Nothing to flush");
 311                                 else
 312                                         printf("*** Flush is complete after %d round(s) ***\n", round);
 313                                 return 0;
 314                         }
 315                         round++;
 316                         if (flush_update() < 0)
 317                                 xfunc_die();
 318                         printf("\n*** Round %d, deleting %d entries ***\n", round, G_filter.flushed);
 319                 }
 320                 bb_error_msg_and_die("*** Flush not complete bailing out after %d rounds", MAX_ROUNDS);
 321         }
 322
 323         ndm.ndm_family = G_filter.family;
 324
 325         if (rtnl_dump_request(&rth, RTM_GETNEIGH, &ndm, sizeof(struct ndmsg)) < 0) {
 326                 bb_perror_msg_and_die("can't send dump request");
 327         }
 328
 329         if (xrtnl_dump_filter(&rth, print_neigh, NULL) < 0) {
 330                 bb_error_msg_and_die("dump terminated");
 331         }
 332
 333         return 0;
 334 }
 335
 336 /* Return value becomes exitcode. It's okay to not return at all */
 337 int FAST_FUNC do_ipneigh(char **argv)
 338 {
 339         static const char ip_neigh_commands[] ALIGN1 =
 340                 /*0-1*/ "show\0"  "flush\0";
 341         int command_num;
 342
 343         INIT_G();
 344
 345         if (!*argv)
 346                 return ipneigh_list_or_flush(argv, 0);
 347
 348         command_num = index_in_substrings(ip_neigh_commands, *argv);
 349         switch (command_num) {
 350                 case 0: /* show */
 351                         return ipneigh_list_or_flush(argv + 1, 0);
 352                 case 1: /* flush */
 353                         return ipneigh_list_or_flush(argv + 1, 1);
 354         }
 355         invarg_1_to_2(*argv, applet_name);
 356         return 1;
 357 }