networking/libiproute/iproute.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * iproute.c            "ip route".
   4  *
   5  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
   6  *
   7  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
   8  *
   9  *
  10  * Changes:
  11  *
  12  * Rani Assaf <rani@magic.metawire.com> 980929: resolve addresses
  13  * Kunihiro Ishiguro <kunihiro@zebra.org> 001102: rtnh_ifindex was not initialized
  14  */
  15
  16 #include "ip_common.h"  /* #include "libbb.h" is inside */
  17 #include "rt_names.h"
  18 #include "utils.h"
  19
  20 #ifndef RTAX_RTTVAR
  21 #define RTAX_RTTVAR RTAX_HOPS
  22 #endif
  23
  24
  25 typedef struct filter_t {
  26         int tb;
  27         smallint flushed;
  28         char *flushb;
  29         int flushp;
  30         int flushe;
  31         struct rtnl_handle *rth;
  32         int protocol, protocolmask;
  33         int scope, scopemask;
  34         int type, typemask;
  35         int tos, tosmask;
  36         int iif, iifmask;
  37         int oif, oifmask;
  38         int realm, realmmask;
  39         inet_prefix rprefsrc;
  40         inet_prefix rvia;
  41         inet_prefix rdst;
  42         inet_prefix mdst;
  43         inet_prefix rsrc;
  44         inet_prefix msrc;
  45 } filter_t;
  46
  47 #define filter (*(filter_t*)&bb_common_bufsiz1)
  48
  49 static int flush_update(void)
  50 {
  51         if (rtnl_send(filter.rth, filter.flushb, filter.flushp) < 0) {
  52                 bb_perror_msg("failed to send flush request");
  53                 return -1;
  54         }
  55         filter.flushp = 0;
  56         return 0;
  57 }
  58
  59 static unsigned get_hz(void)
  60 {
  61         static unsigned hz_internal;
  62         FILE *fp;
  63
  64         if (hz_internal)
  65                 return hz_internal;
  66
  67         fp = fopen_for_read("/proc/net/psched");
  68         if (fp) {
  69                 unsigned nom, denom;
  70
  71                 if (fscanf(fp, "%*08x%*08x%08x%08x", &nom, &denom) == 2)
  72                         if (nom == 1000000)
  73                                 hz_internal = denom;
  74                 fclose(fp);
  75         }
  76         if (!hz_internal)
  77                 hz_internal = sysconf(_SC_CLK_TCK);
  78         return hz_internal;
  79 }
  80
  81 static int print_route(const struct sockaddr_nl *who UNUSED_PARAM,
  82                 struct nlmsghdr *n, void *arg UNUSED_PARAM)
  83 {
  84         struct rtmsg *r = NLMSG_DATA(n);
  85         int len = n->nlmsg_len;
  86         struct rtattr * tb[RTA_MAX+1];
  87         char abuf[256];
  88         inet_prefix dst;
  89         inet_prefix src;
  90         int host_len = -1;
  91         SPRINT_BUF(b1);
  92
  93         if (n->nlmsg_type != RTM_NEWROUTE && n->nlmsg_type != RTM_DELROUTE) {
  94                 fprintf(stderr, "Not a route: %08x %08x %08x\n",
  95                         n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
  96                 return 0;
  97         }
  98         if (filter.flushb && n->nlmsg_type != RTM_NEWROUTE)
  99                 return 0;
 100         len -= NLMSG_LENGTH(sizeof(*r));
 101         if (len < 0)
 102                 bb_error_msg_and_die("wrong nlmsg len %d", len);
 103
 104         if (r->rtm_family == AF_INET6)
 105                 host_len = 128;
 106         else if (r->rtm_family == AF_INET)
 107                 host_len = 32;
 108
 109         if (r->rtm_family == AF_INET6) {
 110                 if (filter.tb) {
 111                         if (filter.tb < 0) {
 112                                 if (!(r->rtm_flags & RTM_F_CLONED)) {
 113                                         return 0;
 114                                 }
 115                         } else {
 116                                 if (r->rtm_flags & RTM_F_CLONED) {
 117                                         return 0;
 118                                 }
 119                                 if (filter.tb == RT_TABLE_LOCAL) {
 120                                         if (r->rtm_type != RTN_LOCAL) {
 121                                                 return 0;
 122                                         }
 123                                 } else if (filter.tb == RT_TABLE_MAIN) {
 124                                         if (r->rtm_type == RTN_LOCAL) {
 125                                                 return 0;
 126                                         }
 127                                 } else {
 128                                         return 0;
 129                                 }
 130                         }
 131                 }
 132         } else {
 133                 if (filter.tb > 0 && filter.tb != r->rtm_table) {
 134                         return 0;
 135                 }
 136         }
 137         if (filter.rdst.family &&
 138             (r->rtm_family != filter.rdst.family || filter.rdst.bitlen > r->rtm_dst_len)) {
 139                 return 0;
 140         }
 141         if (filter.mdst.family &&
 142             (r->rtm_family != filter.mdst.family ||
 143              (filter.mdst.bitlen >= 0 && filter.mdst.bitlen < r->rtm_dst_len))) {
 144                 return 0;
 145         }
 146         if (filter.rsrc.family &&
 147             (r->rtm_family != filter.rsrc.family || filter.rsrc.bitlen > r->rtm_src_len)) {
 148                 return 0;
 149         }
 150         if (filter.msrc.family &&
 151             (r->rtm_family != filter.msrc.family ||
 152              (filter.msrc.bitlen >= 0 && filter.msrc.bitlen < r->rtm_src_len))) {
 153                 return 0;
 154         }
 155
 156         memset(tb, 0, sizeof(tb));
 157         parse_rtattr(tb, RTA_MAX, RTM_RTA(r), len);
 158
 159         if (filter.rdst.family && inet_addr_match(&dst, &filter.rdst, filter.rdst.bitlen))
 160                 return 0;
 161         if (filter.mdst.family && filter.mdst.bitlen >= 0 &&
 162             inet_addr_match(&dst, &filter.mdst, r->rtm_dst_len))
 163                 return 0;
 164
 165         if (filter.rsrc.family && inet_addr_match(&src, &filter.rsrc, filter.rsrc.bitlen))
 166                 return 0;
 167         if (filter.msrc.family && filter.msrc.bitlen >= 0 &&
 168             inet_addr_match(&src, &filter.msrc, r->rtm_src_len))
 169                 return 0;
 170
 171         if (filter.flushb &&
 172             r->rtm_family == AF_INET6 &&
 173             r->rtm_dst_len == 0 &&
 174             r->rtm_type == RTN_UNREACHABLE &&
 175             tb[RTA_PRIORITY] &&
 176             *(int*)RTA_DATA(tb[RTA_PRIORITY]) == -1)
 177                 return 0;
 178
 179         if (filter.flushb) {
 180                 struct nlmsghdr *fn;
 181                 if (NLMSG_ALIGN(filter.flushp) + n->nlmsg_len > filter.flushe) {
 182                         if (flush_update())
 183                                 bb_error_msg_and_die("flush");
 184                 }
 185                 fn = (struct nlmsghdr*)(filter.flushb + NLMSG_ALIGN(filter.flushp));
 186                 memcpy(fn, n, n->nlmsg_len);
 187                 fn->nlmsg_type = RTM_DELROUTE;
 188                 fn->nlmsg_flags = NLM_F_REQUEST;
 189                 fn->nlmsg_seq = ++filter.rth->seq;
 190                 filter.flushp = (((char*)fn) + n->nlmsg_len) - filter.flushb;
 191                 filter.flushed = 1;
 192                 return 0;
 193         }
 194
 195         if (n->nlmsg_type == RTM_DELROUTE) {
 196                 printf("Deleted ");
 197         }
 198         if (r->rtm_type != RTN_UNICAST && !filter.type) {
 199                 printf("%s ", rtnl_rtntype_n2a(r->rtm_type, b1, sizeof(b1)));
 200         }
 201
 202         if (tb[RTA_DST]) {
 203                 if (r->rtm_dst_len != host_len) {
 204                         printf("%s/%u ", rt_addr_n2a(r->rtm_family,
 205                                                 RTA_DATA(tb[RTA_DST]),
 206                                                 abuf, sizeof(abuf)),
 207                                         r->rtm_dst_len
 208                                         );
 209                 } else {
 210                         printf("%s ", format_host(r->rtm_family,
 211                                                 RTA_PAYLOAD(tb[RTA_DST]),
 212                                                 RTA_DATA(tb[RTA_DST]),
 213                                                 abuf, sizeof(abuf))
 214                                         );
 215                 }
 216         } else if (r->rtm_dst_len) {
 217                 printf("0/%d ", r->rtm_dst_len);
 218         } else {
 219                 printf("default ");
 220         }
 221         if (tb[RTA_SRC]) {
 222                 if (r->rtm_src_len != host_len) {
 223                         printf("from %s/%u ", rt_addr_n2a(r->rtm_family,
 224                                                 RTA_DATA(tb[RTA_SRC]),
 225                                                 abuf, sizeof(abuf)),
 226                                         r->rtm_src_len
 227                                         );
 228                 } else {
 229                         printf("from %s ", format_host(r->rtm_family,
 230                                                 RTA_PAYLOAD(tb[RTA_SRC]),
 231                                                 RTA_DATA(tb[RTA_SRC]),
 232                                                 abuf, sizeof(abuf))
 233                                         );
 234                 }
 235         } else if (r->rtm_src_len) {
 236                 printf("from 0/%u ", r->rtm_src_len);
 237         }
 238         if (tb[RTA_GATEWAY] && filter.rvia.bitlen != host_len) {
 239                 printf("via %s ", format_host(r->rtm_family,
 240                                         RTA_PAYLOAD(tb[RTA_GATEWAY]),
 241                                         RTA_DATA(tb[RTA_GATEWAY]),
 242                                         abuf, sizeof(abuf)));
 243         }
 244         if (tb[RTA_OIF] && filter.oifmask != -1) {
 245                 printf("dev %s ", ll_index_to_name(*(int*)RTA_DATA(tb[RTA_OIF])));
 246         }
 247
 248         if (tb[RTA_PREFSRC] && filter.rprefsrc.bitlen != host_len) {
 249                 /* Do not use format_host(). It is our local addr
 250                    and symbolic name will not be useful.
 251                  */
 252                 printf(" src %s ", rt_addr_n2a(r->rtm_family,
 253                                         RTA_DATA(tb[RTA_PREFSRC]),
 254                                         abuf, sizeof(abuf)));
 255         }
 256         if (tb[RTA_PRIORITY]) {
 257                 printf(" metric %d ", *(uint32_t*)RTA_DATA(tb[RTA_PRIORITY]));
 258         }
 259         if (r->rtm_family == AF_INET6) {
 260                 struct rta_cacheinfo *ci = NULL;
 261                 if (tb[RTA_CACHEINFO]) {
 262                         ci = RTA_DATA(tb[RTA_CACHEINFO]);
 263                 }
 264                 if ((r->rtm_flags & RTM_F_CLONED) || (ci && ci->rta_expires)) {
 265                         if (r->rtm_flags & RTM_F_CLONED) {
 266                                 printf("%c    cache ", _SL_);
 267                         }
 268                         if (ci->rta_expires) {
 269                                 printf(" expires %dsec", ci->rta_expires / get_hz());
 270                         }
 271                         if (ci->rta_error != 0) {
 272                                 printf(" error %d", ci->rta_error);
 273                         }
 274                 } else if (ci) {
 275                         if (ci->rta_error != 0)
 276                                 printf(" error %d", ci->rta_error);
 277                 }
 278         }
 279         if (tb[RTA_IIF] && filter.iifmask != -1) {
 280                 printf(" iif %s", ll_index_to_name(*(int*)RTA_DATA(tb[RTA_IIF])));
 281         }
 282         bb_putchar('\n');
 283         return 0;
 284 }
 285
 286 /* Return value becomes exitcode. It's okay to not return at all */
 287 static int iproute_modify(int cmd, unsigned flags, char **argv)
 288 {
 289         static const char keywords[] ALIGN1 =
 290                 "src\0""via\0""mtu\0""lock\0""protocol\0"IF_FEATURE_IP_RULE("table\0")
 291                 "dev\0""oif\0""to\0""metric\0";
 292         enum {
 293                 ARG_src,
 294                 ARG_via,
 295                 ARG_mtu, PARM_lock,
 296                 ARG_protocol,
 297 IF_FEATURE_IP_RULE(ARG_table,)
 298                 ARG_dev,
 299                 ARG_oif,
 300                 ARG_to,
 301                 ARG_metric,
 302         };
 303         enum {
 304                 gw_ok = 1 << 0,
 305                 dst_ok = 1 << 1,
 306                 proto_ok = 1 << 2,
 307                 type_ok = 1 << 3
 308         };
 309         struct rtnl_handle rth;
 310         struct {
 311                 struct nlmsghdr         n;
 312                 struct rtmsg            r;
 313                 char                    buf[1024];
 314         } req;
 315         char mxbuf[256];
 316         struct rtattr * mxrta = (void*)mxbuf;
 317         unsigned mxlock = 0;
 318         char *d = NULL;
 319         smalluint ok = 0;
 320         int arg;
 321
 322         memset(&req, 0, sizeof(req));
 323
 324         req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
 325         req.n.nlmsg_flags = NLM_F_REQUEST | flags;
 326         req.n.nlmsg_type = cmd;
 327         req.r.rtm_family = preferred_family;
 328         if (RT_TABLE_MAIN) /* if it is zero, memset already did it */
 329                 req.r.rtm_table = RT_TABLE_MAIN;
 330         if (RT_SCOPE_NOWHERE)
 331                 req.r.rtm_scope = RT_SCOPE_NOWHERE;
 332
 333         if (cmd != RTM_DELROUTE) {
 334                 req.r.rtm_protocol = RTPROT_BOOT;
 335                 req.r.rtm_scope = RT_SCOPE_UNIVERSE;
 336                 req.r.rtm_type = RTN_UNICAST;
 337         }
 338
 339         mxrta->rta_type = RTA_METRICS;
 340         mxrta->rta_len = RTA_LENGTH(0);
 341
 342         while (*argv) {
 343                 arg = index_in_substrings(keywords, *argv);
 344                 if (arg == ARG_src) {
 345                         inet_prefix addr;
 346                         NEXT_ARG();
 347                         get_addr(&addr, *argv, req.r.rtm_family);
 348                         if (req.r.rtm_family == AF_UNSPEC)
 349                                 req.r.rtm_family = addr.family;
 350                         addattr_l(&req.n, sizeof(req), RTA_PREFSRC, &addr.data, addr.bytelen);
 351                 } else if (arg == ARG_via) {
 352                         inet_prefix addr;
 353                         ok |= gw_ok;
 354                         NEXT_ARG();
 355                         get_addr(&addr, *argv, req.r.rtm_family);
 356                         if (req.r.rtm_family == AF_UNSPEC) {
 357                                 req.r.rtm_family = addr.family;
 358                         }
 359                         addattr_l(&req.n, sizeof(req), RTA_GATEWAY, &addr.data, addr.bytelen);
 360                 } else if (arg == ARG_mtu) {
 361                         unsigned mtu;
 362                         NEXT_ARG();
 363                         if (index_in_strings(keywords, *argv) == PARM_lock) {
 364                                 mxlock |= (1 << RTAX_MTU);
 365                                 NEXT_ARG();
 366                         }
 367                         mtu = get_unsigned(*argv, "mtu");
 368                         rta_addattr32(mxrta, sizeof(mxbuf), RTAX_MTU, mtu);
 369                 } else if (arg == ARG_protocol) {
 370                         uint32_t prot;
 371                         NEXT_ARG();
 372                         if (rtnl_rtprot_a2n(&prot, *argv))
 373                                 invarg(*argv, "protocol");
 374                         req.r.rtm_protocol = prot;
 375                         ok |= proto_ok;
 376 #if ENABLE_FEATURE_IP_RULE
 377                 } else if (arg == ARG_table) {
 378                         uint32_t tid;
 379                         NEXT_ARG();
 380                         if (rtnl_rttable_a2n(&tid, *argv))
 381                                 invarg(*argv, "table");
 382                         req.r.rtm_table = tid;
 383 #endif
 384                 } else if (arg == ARG_dev || arg == ARG_oif) {
 385                         NEXT_ARG();
 386                         d = *argv;
 387                 } else if (arg == ARG_metric) {
 388                         uint32_t metric;
 389                         NEXT_ARG();
 390                         metric = get_u32(*argv, "metric");
 391                         addattr32(&req.n, sizeof(req), RTA_PRIORITY, metric);
 392                 } else {
 393                         int type;
 394                         inet_prefix dst;
 395
 396                         if (arg == ARG_to) {
 397                                 NEXT_ARG();
 398                         }
 399                         if ((**argv < '0' || **argv > '9')
 400                          && rtnl_rtntype_a2n(&type, *argv) == 0) {
 401                                 NEXT_ARG();
 402                                 req.r.rtm_type = type;
 403                                 ok |= type_ok;
 404                         }
 405
 406                         if (ok & dst_ok) {
 407                                 duparg2("to", *argv);
 408                         }
 409                         get_prefix(&dst, *argv, req.r.rtm_family);
 410                         if (req.r.rtm_family == AF_UNSPEC) {
 411                                 req.r.rtm_family = dst.family;
 412                         }
 413                         req.r.rtm_dst_len = dst.bitlen;
 414                         ok |= dst_ok;
 415                         if (dst.bytelen) {
 416                                 addattr_l(&req.n, sizeof(req), RTA_DST, &dst.data, dst.bytelen);
 417                         }
 418                 }
 419                 argv++;
 420         }
 421
 422         xrtnl_open(&rth);
 423
 424         if (d)  {
 425                 int idx;
 426
 427                 ll_init_map(&rth);
 428
 429                 if (d) {
 430                         idx = xll_name_to_index(d);
 431                         addattr32(&req.n, sizeof(req), RTA_OIF, idx);
 432                 }
 433         }
 434
 435         if (mxrta->rta_len > RTA_LENGTH(0)) {
 436                 if (mxlock) {
 437                         rta_addattr32(mxrta, sizeof(mxbuf), RTAX_LOCK, mxlock);
 438                 }
 439                 addattr_l(&req.n, sizeof(req), RTA_METRICS, RTA_DATA(mxrta), RTA_PAYLOAD(mxrta));
 440         }
 441
 442         if (req.r.rtm_type == RTN_LOCAL || req.r.rtm_type == RTN_NAT)
 443                 req.r.rtm_scope = RT_SCOPE_HOST;
 444         else if (req.r.rtm_type == RTN_BROADCAST ||
 445                         req.r.rtm_type == RTN_MULTICAST ||
 446                         req.r.rtm_type == RTN_ANYCAST)
 447                 req.r.rtm_scope = RT_SCOPE_LINK;
 448         else if (req.r.rtm_type == RTN_UNICAST || req.r.rtm_type == RTN_UNSPEC) {
 449                 if (cmd == RTM_DELROUTE)
 450                         req.r.rtm_scope = RT_SCOPE_NOWHERE;
 451                 else if (!(ok & gw_ok))
 452                         req.r.rtm_scope = RT_SCOPE_LINK;
 453         }
 454
 455         if (req.r.rtm_family == AF_UNSPEC) {
 456                 req.r.rtm_family = AF_INET;
 457         }
 458
 459         if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0) {
 460                 return 2;
 461         }
 462
 463         return 0;
 464 }
 465
 466 static int rtnl_rtcache_request(struct rtnl_handle *rth, int family)
 467 {
 468         struct {
 469                 struct nlmsghdr nlh;
 470                 struct rtmsg rtm;
 471         } req;
 472         struct sockaddr_nl nladdr;
 473
 474         memset(&nladdr, 0, sizeof(nladdr));
 475         memset(&req, 0, sizeof(req));
 476         nladdr.nl_family = AF_NETLINK;
 477
 478         req.nlh.nlmsg_len = sizeof(req);
 479         if (RTM_GETROUTE)
 480                 req.nlh.nlmsg_type = RTM_GETROUTE;
 481         if (NLM_F_ROOT | NLM_F_REQUEST)
 482                 req.nlh.nlmsg_flags = NLM_F_ROOT | NLM_F_REQUEST;
 483         /*req.nlh.nlmsg_pid = 0; - memset did it already */
 484         req.nlh.nlmsg_seq = rth->dump = ++rth->seq;
 485         req.rtm.rtm_family = family;
 486         if (RTM_F_CLONED)
 487                 req.rtm.rtm_flags = RTM_F_CLONED;
 488
 489         return xsendto(rth->fd, (void*)&req, sizeof(req), (struct sockaddr*)&nladdr, sizeof(nladdr));
 490 }
 491
 492 static void iproute_flush_cache(void)
 493 {
 494         static const char fn[] ALIGN1 = "/proc/sys/net/ipv4/route/flush";
 495         int flush_fd = open_or_warn(fn, O_WRONLY);
 496
 497         if (flush_fd < 0) {
 498                 return;
 499         }
 500
 501         if (write(flush_fd, "-1", 2) < 2) {
 502                 bb_perror_msg("cannot flush routing cache");
 503                 return;
 504         }
 505         close(flush_fd);
 506 }
 507
 508 static void iproute_reset_filter(void)
 509 {
 510         memset(&filter, 0, sizeof(filter));
 511         filter.mdst.bitlen = -1;
 512         filter.msrc.bitlen = -1;
 513 }
 514
 515 /* Return value becomes exitcode. It's okay to not return at all */
 516 static int iproute_list_or_flush(char **argv, int flush)
 517 {
 518         int do_ipv6 = preferred_family;
 519         struct rtnl_handle rth;
 520         char *id = NULL;
 521         char *od = NULL;
 522         static const char keywords[] ALIGN1 =
 523                 /* "ip route list/flush" parameters: */
 524                 "protocol\0" "dev\0"   "oif\0"   "iif\0"
 525                 "via\0"      "table\0" "cache\0"
 526                 "from\0"     "to\0"
 527                 /* and possible further keywords */
 528                 "all\0"
 529                 "root\0"
 530                 "match\0"
 531                 "exact\0"
 532                 "main\0"
 533                 ;
 534         enum {
 535                 KW_proto, KW_dev,   KW_oif,  KW_iif,
 536                 KW_via,   KW_table, KW_cache,
 537                 KW_from,  KW_to,
 538                 /* */
 539                 KW_all,
 540                 KW_root,
 541                 KW_match,
 542                 KW_exact,
 543                 KW_main,
 544         };
 545         int arg, parm;
 546
 547         iproute_reset_filter();
 548         filter.tb = RT_TABLE_MAIN;
 549
 550         if (flush && !*argv)
 551                 bb_error_msg_and_die(bb_msg_requires_arg, "\"ip route flush\"");
 552
 553         while (*argv) {
 554                 arg = index_in_substrings(keywords, *argv);
 555                 if (arg == KW_proto) {
 556                         uint32_t prot = 0;
 557                         NEXT_ARG();
 558                         filter.protocolmask = -1;
 559                         if (rtnl_rtprot_a2n(&prot, *argv)) {
 560                                 if (index_in_strings(keywords, *argv) != KW_all)
 561                                         invarg(*argv, "protocol");
 562                                 prot = 0;
 563                                 filter.protocolmask = 0;
 564                         }
 565                         filter.protocol = prot;
 566                 } else if (arg == KW_dev || arg == KW_oif) {
 567                         NEXT_ARG();
 568                         od = *argv;
 569                 } else if (arg == KW_iif) {
 570                         NEXT_ARG();
 571                         id = *argv;
 572                 } else if (arg == KW_via) {
 573                         NEXT_ARG();
 574                         get_prefix(&filter.rvia, *argv, do_ipv6);
 575                 } else if (arg == KW_table) { /* table all/cache/main */
 576                         NEXT_ARG();
 577                         parm = index_in_substrings(keywords, *argv);
 578                         if (parm == KW_cache)
 579                                 filter.tb = -1;
 580                         else if (parm == KW_all)
 581                                 filter.tb = 0;
 582                         else if (parm != KW_main) {
 583 #if ENABLE_FEATURE_IP_RULE
 584                                 uint32_t tid;
 585                                 if (rtnl_rttable_a2n(&tid, *argv))
 586                                         invarg(*argv, "table");
 587                                 filter.tb = tid;
 588 #else
 589                                 invarg(*argv, "table");
 590 #endif
 591                         }
 592                 } else if (arg == KW_cache) {
 593                         /* The command 'ip route flush cache' is used by OpenSWAN.
 594                          * Assuming it's a synonym for 'ip route flush table cache' */
 595                         filter.tb = -1;
 596                 } else if (arg == KW_from) {
 597                         NEXT_ARG();
 598                         parm = index_in_substrings(keywords, *argv);
 599                         if (parm == KW_root) {
 600                                 NEXT_ARG();
 601                                 get_prefix(&filter.rsrc, *argv, do_ipv6);
 602                         } else if (parm == KW_match) {
 603                                 NEXT_ARG();
 604                                 get_prefix(&filter.msrc, *argv, do_ipv6);
 605                         } else {
 606                                 if (parm == KW_exact)
 607                                         NEXT_ARG();
 608                                 get_prefix(&filter.msrc, *argv, do_ipv6);
 609                                 filter.rsrc = filter.msrc;
 610                         }
 611                 } else { /* "to" is the default parameter */
 612                         if (arg == KW_to) {
 613                                 NEXT_ARG();
 614                                 arg = index_in_substrings(keywords, *argv);
 615                         }
 616                         /* parm = arg; - would be more plausible, but we reuse 'arg' here */
 617                         if (arg == KW_root) {
 618                                 NEXT_ARG();
 619                                 get_prefix(&filter.rdst, *argv, do_ipv6);
 620                         } else if (arg == KW_match) {
 621                                 NEXT_ARG();
 622                                 get_prefix(&filter.mdst, *argv, do_ipv6);
 623                         } else { /* "to exact" is the default */
 624                                 if (arg == KW_exact)
 625                                         NEXT_ARG();
 626                                 get_prefix(&filter.mdst, *argv, do_ipv6);
 627                                 filter.rdst = filter.mdst;
 628                         }
 629                 }
 630                 argv++;
 631         }
 632
 633         if (do_ipv6 == AF_UNSPEC && filter.tb) {
 634                 do_ipv6 = AF_INET;
 635         }
 636
 637         xrtnl_open(&rth);
 638         ll_init_map(&rth);
 639
 640         if (id || od)  {
 641                 int idx;
 642
 643                 if (id) {
 644                         idx = xll_name_to_index(id);
 645                         filter.iif = idx;
 646                         filter.iifmask = -1;
 647                 }
 648                 if (od) {
 649                         idx = xll_name_to_index(od);
 650                         filter.oif = idx;
 651                         filter.oifmask = -1;
 652                 }
 653         }
 654
 655         if (flush) {
 656                 char flushb[4096-512];
 657
 658                 if (filter.tb == -1) { /* "flush table cache" */
 659                         if (do_ipv6 != AF_INET6)
 660                                 iproute_flush_cache();
 661                         if (do_ipv6 == AF_INET)
 662                                 return 0;
 663                 }
 664
 665                 filter.flushb = flushb;
 666                 filter.flushp = 0;
 667                 filter.flushe = sizeof(flushb);
 668                 filter.rth = &rth;
 669
 670                 for (;;) {
 671                         xrtnl_wilddump_request(&rth, do_ipv6, RTM_GETROUTE);
 672                         filter.flushed = 0;
 673                         xrtnl_dump_filter(&rth, print_route, NULL);
 674                         if (filter.flushed == 0)
 675                                 return 0;
 676                         if (flush_update())
 677                                 return 1;
 678                 }
 679         }
 680
 681         if (filter.tb != -1) {
 682                 xrtnl_wilddump_request(&rth, do_ipv6, RTM_GETROUTE);
 683         } else if (rtnl_rtcache_request(&rth, do_ipv6) < 0) {
 684                 bb_perror_msg_and_die("cannot send dump request");
 685         }
 686         xrtnl_dump_filter(&rth, print_route, NULL);
 687
 688         return 0;
 689 }
 690
 691
 692 /* Return value becomes exitcode. It's okay to not return at all */
 693 static int iproute_get(char **argv)
 694 {
 695         struct rtnl_handle rth;
 696         struct {
 697                 struct nlmsghdr n;
 698                 struct rtmsg    r;
 699                 char            buf[1024];
 700         } req;
 701         char *idev = NULL;
 702         char *odev = NULL;
 703         bool connected = 0;
 704         bool from_ok = 0;
 705         static const char options[] ALIGN1 =
 706                 "from\0""iif\0""oif\0""dev\0""notify\0""connected\0""to\0";
 707
 708         memset(&req, 0, sizeof(req));
 709
 710         iproute_reset_filter();
 711
 712         req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
 713         if (NLM_F_REQUEST)
 714                 req.n.nlmsg_flags = NLM_F_REQUEST;
 715         if (RTM_GETROUTE)
 716                 req.n.nlmsg_type = RTM_GETROUTE;
 717         req.r.rtm_family = preferred_family;
 718         /*req.r.rtm_table = 0; - memset did this already */
 719         /*req.r.rtm_protocol = 0;*/
 720         /*req.r.rtm_scope = 0;*/
 721         /*req.r.rtm_type = 0;*/
 722         /*req.r.rtm_src_len = 0;*/
 723         /*req.r.rtm_dst_len = 0;*/
 724         /*req.r.rtm_tos = 0;*/
 725
 726         while (*argv) {
 727                 switch (index_in_strings(options, *argv)) {
 728                         case 0: /* from */
 729                         {
 730                                 inet_prefix addr;
 731                                 NEXT_ARG();
 732                                 from_ok = 1;
 733                                 get_prefix(&addr, *argv, req.r.rtm_family);
 734                                 if (req.r.rtm_family == AF_UNSPEC) {
 735                                         req.r.rtm_family = addr.family;
 736                                 }
 737                                 if (addr.bytelen) {
 738                                         addattr_l(&req.n, sizeof(req), RTA_SRC, &addr.data, addr.bytelen);
 739                                 }
 740                                 req.r.rtm_src_len = addr.bitlen;
 741                                 break;
 742                         }
 743                         case 1: /* iif */
 744                                 NEXT_ARG();
 745                                 idev = *argv;
 746                                 break;
 747                         case 2: /* oif */
 748                         case 3: /* dev */
 749                                 NEXT_ARG();
 750                                 odev = *argv;
 751                                 break;
 752                         case 4: /* notify */
 753                                 req.r.rtm_flags |= RTM_F_NOTIFY;
 754                                 break;
 755                         case 5: /* connected */
 756                                 connected = 1;
 757                                 break;
 758                         case 6: /* to */
 759                                 NEXT_ARG();
 760                         default:
 761                         {
 762                                 inet_prefix addr;
 763                                 get_prefix(&addr, *argv, req.r.rtm_family);
 764                                 if (req.r.rtm_family == AF_UNSPEC) {
 765                                         req.r.rtm_family = addr.family;
 766                                 }
 767                                 if (addr.bytelen) {
 768                                         addattr_l(&req.n, sizeof(req), RTA_DST, &addr.data, addr.bytelen);
 769                                 }
 770                                 req.r.rtm_dst_len = addr.bitlen;
 771                         }
 772                         argv++;
 773                 }
 774         }
 775
 776         if (req.r.rtm_dst_len == 0) {
 777                 bb_error_msg_and_die("need at least destination address");
 778         }
 779
 780         xrtnl_open(&rth);
 781
 782         ll_init_map(&rth);
 783
 784         if (idev || odev)  {
 785                 int idx;
 786
 787                 if (idev) {
 788                         idx = xll_name_to_index(idev);
 789                         addattr32(&req.n, sizeof(req), RTA_IIF, idx);
 790                 }
 791                 if (odev) {
 792                         idx = xll_name_to_index(odev);
 793                         addattr32(&req.n, sizeof(req), RTA_OIF, idx);
 794                 }
 795         }
 796
 797         if (req.r.rtm_family == AF_UNSPEC) {
 798                 req.r.rtm_family = AF_INET;
 799         }
 800
 801         if (rtnl_talk(&rth, &req.n, 0, 0, &req.n, NULL, NULL) < 0) {
 802                 return 2;
 803         }
 804
 805         if (connected && !from_ok) {
 806                 struct rtmsg *r = NLMSG_DATA(&req.n);
 807                 int len = req.n.nlmsg_len;
 808                 struct rtattr * tb[RTA_MAX+1];
 809
 810                 print_route(NULL, &req.n, NULL);
 811
 812                 if (req.n.nlmsg_type != RTM_NEWROUTE) {
 813                         bb_error_msg_and_die("not a route?");
 814                 }
 815                 len -= NLMSG_LENGTH(sizeof(*r));
 816                 if (len < 0) {
 817                         bb_error_msg_and_die("wrong len %d", len);
 818                 }
 819
 820                 memset(tb, 0, sizeof(tb));
 821                 parse_rtattr(tb, RTA_MAX, RTM_RTA(r), len);
 822
 823                 if (tb[RTA_PREFSRC]) {
 824                         tb[RTA_PREFSRC]->rta_type = RTA_SRC;
 825                         r->rtm_src_len = 8*RTA_PAYLOAD(tb[RTA_PREFSRC]);
 826                 } else if (!tb[RTA_SRC]) {
 827                         bb_error_msg_and_die("failed to connect the route");
 828                 }
 829                 if (!odev && tb[RTA_OIF]) {
 830                         tb[RTA_OIF]->rta_type = 0;
 831                 }
 832                 if (tb[RTA_GATEWAY]) {
 833                         tb[RTA_GATEWAY]->rta_type = 0;
 834                 }
 835                 if (!idev && tb[RTA_IIF]) {
 836                         tb[RTA_IIF]->rta_type = 0;
 837                 }
 838                 req.n.nlmsg_flags = NLM_F_REQUEST;
 839                 req.n.nlmsg_type = RTM_GETROUTE;
 840
 841                 if (rtnl_talk(&rth, &req.n, 0, 0, &req.n, NULL, NULL) < 0) {
 842                         return 2;
 843                 }
 844         }
 845         print_route(NULL, &req.n, NULL);
 846         return 0;
 847 }
 848
 849 /* Return value becomes exitcode. It's okay to not return at all */
 850 int do_iproute(char **argv)
 851 {
 852         static const char ip_route_commands[] ALIGN1 =
 853         /*0-3*/ "add\0""append\0""change\0""chg\0"
 854         /*4-7*/ "delete\0""get\0""list\0""show\0"
 855         /*8..*/ "prepend\0""replace\0""test\0""flush\0";
 856         int command_num;
 857         unsigned flags = 0;
 858         int cmd = RTM_NEWROUTE;
 859
 860         if (!*argv)
 861                 return iproute_list_or_flush(argv, 0);
 862
 863         /* "Standard" 'ip r a' treats 'a' as 'add', not 'append' */
 864         /* It probably means that it is using "first match" rule */
 865         command_num = index_in_substrings(ip_route_commands, *argv);
 866
 867         switch (command_num) {
 868                 case 0: /* add */
 869                         flags = NLM_F_CREATE|NLM_F_EXCL;
 870                         break;
 871                 case 1: /* append */
 872                         flags = NLM_F_CREATE|NLM_F_APPEND;
 873                         break;
 874                 case 2: /* change */
 875                 case 3: /* chg */
 876                         flags = NLM_F_REPLACE;
 877                         break;
 878                 case 4: /* delete */
 879                         cmd = RTM_DELROUTE;
 880                         break;
 881                 case 5: /* get */
 882                         return iproute_get(argv+1);
 883                 case 6: /* list */
 884                 case 7: /* show */
 885                         return iproute_list_or_flush(argv+1, 0);
 886                 case 8: /* prepend */
 887                         flags = NLM_F_CREATE;
 888                         break;
 889                 case 9: /* replace */
 890                         flags = NLM_F_CREATE|NLM_F_REPLACE;
 891                         break;
 892                 case 10: /* test */
 893                         flags = NLM_F_EXCL;
 894                         break;
 895                 case 11: /* flush */
 896                         return iproute_list_or_flush(argv+1, 1);
 897                 default:
 898                         bb_error_msg_and_die("unknown command %s", *argv);
 899         }
 900
 901         return iproute_modify(cmd, flags, argv+1);
 902 }