networking/brctl.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Small implementation of brctl for busybox.
   4  *
   5  * Copyright (C) 2008 by Bernhard Reutner-Fischer
   6  *
   7  * Some helper functions from bridge-utils are
   8  * Copyright (C) 2000 Lennert Buytenhek
   9  *
  10  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  11  */
  12 //config:config BRCTL
  13 //config:       bool "brctl (4.7 kb)"
  14 //config:       default y
  15 //config:       select PLATFORM_LINUX
  16 //config:       help
  17 //config:       Manage ethernet bridges.
  18 //config:       Supports addbr/delbr and addif/delif.
  19 //config:
  20 //config:config FEATURE_BRCTL_FANCY
  21 //config:       bool "Fancy options"
  22 //config:       default y
  23 //config:       depends on BRCTL
  24 //config:       help
  25 //config:       Add support for extended option like:
  26 //config:               setageing, setfd, sethello, setmaxage,
  27 //config:               setpathcost, setportprio, setbridgeprio,
  28 //config:               stp
  29 //config:       This adds about 600 bytes.
  30 //config:
  31 //config:config FEATURE_BRCTL_SHOW
  32 //config:       bool "Support show"
  33 //config:       default y
  34 //config:       depends on BRCTL && FEATURE_BRCTL_FANCY
  35 //config:       help
  36 //config:       Add support for option which prints the current config:
  37 //config:               show
  38
  39 //applet:IF_BRCTL(APPLET_NOEXEC(brctl, brctl, BB_DIR_USR_SBIN, BB_SUID_DROP, brctl))
  40
  41 //kbuild:lib-$(CONFIG_BRCTL) += brctl.o
  42
  43 //usage:#define brctl_trivial_usage
  44 //usage:       "COMMAND [BRIDGE [ARGS]]"
  45 //usage:#define brctl_full_usage "\n\n"
  46 //usage:       "Manage ethernet bridges"
  47 //usage:     "\nCommands:"
  48 //usage:        IF_FEATURE_BRCTL_SHOW(
  49 //usage:     "\n        show [BRIDGE]...        Show bridges"
  50 //usage:        )
  51 //usage:     "\n        addbr BRIDGE            Create BRIDGE"
  52 //usage:     "\n        delbr BRIDGE            Delete BRIDGE"
  53 //usage:     "\n        addif BRIDGE IFACE      Add IFACE to BRIDGE"
  54 //usage:     "\n        delif BRIDGE IFACE      Delete IFACE from BRIDGE"
  55 //usage:        IF_FEATURE_BRCTL_FANCY(
  56 //usage:     "\n        showmacs BRIDGE                 List MAC addresses"
  57 //usage:     "\n        showstp BRIDGE                  Show STP info"
  58 //usage:     "\n        stp BRIDGE 1/yes/on|0/no/off    Set STP on/off"
  59 //usage:     "\n        setageing BRIDGE SECONDS        Set ageing time"
  60 //usage:     "\n        setfd BRIDGE SECONDS            Set bridge forward delay"
  61 //usage:     "\n        sethello BRIDGE SECONDS         Set hello time"
  62 //usage:     "\n        setmaxage BRIDGE SECONDS        Set max message age"
  63 //usage:     "\n        setbridgeprio BRIDGE PRIO       Set bridge priority"
  64 //usage:     "\n        setportprio BRIDGE IFACE PRIO   Set port priority"
  65 //usage:     "\n        setpathcost BRIDGE IFACE COST   Set path cost"
  66 //usage:        )
  67 // Not yet implemented:
  68 //                      hairpin BRIDGE IFACE on|off     Set hairpin on/off
  69
  70 #include "libbb.h"
  71 #include "common_bufsiz.h"
  72 #include <linux/sockios.h>
  73 #include <net/if.h>
  74
  75 #ifndef SIOCBRADDBR
  76 # define SIOCBRADDBR BRCTL_ADD_BRIDGE
  77 #endif
  78 #ifndef SIOCBRDELBR
  79 # define SIOCBRDELBR BRCTL_DEL_BRIDGE
  80 #endif
  81 #ifndef SIOCBRADDIF
  82 # define SIOCBRADDIF BRCTL_ADD_IF
  83 #endif
  84 #ifndef SIOCBRDELIF
  85 # define SIOCBRDELIF BRCTL_DEL_IF
  86 #endif
  87
  88 #if ENABLE_FEATURE_BRCTL_FANCY
  89 static unsigned str_to_jiffies(const char *time_str)
  90 {
  91         double dd;
  92         char *endptr;
  93         dd = /*bb_*/strtod(time_str, &endptr);
  94         if (endptr == time_str || dd < 0)
  95                 bb_error_msg_and_die(bb_msg_invalid_arg_to, time_str, "timespec");
  96
  97         dd *= 100;
  98         /* For purposes of brctl,
  99          * capping SECONDS by ~20 million seconds is quite enough:
 100          */
 101         if (dd > INT_MAX)
 102                 dd = INT_MAX;
 103
 104         return dd;
 105 }
 106 #endif
 107
 108 #define filedata bb_common_bufsiz1
 109
 110 #if ENABLE_FEATURE_BRCTL_SHOW
 111 static int read_file(const char *name)
 112 {
 113         int n = open_read_close(name, filedata, COMMON_BUFSIZE - 1);
 114         if (n < 0) {
 115                 filedata[0] = '\0';
 116         } else {
 117                 filedata[n] = '\0';
 118                 if (n != 0 && filedata[n - 1] == '\n')
 119                         filedata[--n] = '\0';
 120         }
 121         return n;
 122 }
 123
 124 /* NB: we are in /sys/class/net
 125  */
 126 static int show_bridge(const char *name, int need_hdr)
 127 {
 128 /* Output:
 129  *bridge name   bridge id               STP enabled     interfaces
 130  *br0           8000.000000000000       no              eth0
 131  */
 132         char pathbuf[IFNAMSIZ + sizeof("/bridge/bridge_id") + 8];
 133         int tabs;
 134         DIR *ifaces;
 135         struct dirent *ent;
 136         char *sfx;
 137
 138 #if IFNAMSIZ == 16
 139         sfx = pathbuf + sprintf(pathbuf, "%.16s/bridge/", name);
 140 #else
 141         sfx = pathbuf + sprintf(pathbuf, "%.*s/bridge/", (int)IFNAMSIZ, name);
 142 #endif
 143         strcpy(sfx, "bridge_id");
 144         if (read_file(pathbuf) < 0)
 145                 return -1; /* this iface is not a bridge */
 146
 147         if (need_hdr)
 148                 puts("bridge name\tbridge id\t\tSTP enabled\tinterfaces");
 149         printf("%s\t\t%s\t", name, filedata);
 150
 151         strcpy(sfx, "stp_state");
 152         read_file(pathbuf);
 153         if (LONE_CHAR(filedata, '0'))
 154                 strcpy(filedata, "no");
 155         else
 156         if (LONE_CHAR(filedata, '1'))
 157                 strcpy(filedata, "yes");
 158         fputs(filedata, stdout);
 159
 160         /* sfx points past "BR/bridge/", turn it into "BR/brif": */
 161         sfx[-4] = 'f'; sfx[-3] = '\0';
 162         tabs = 0;
 163         ifaces = opendir(pathbuf);
 164         if (ifaces) {
 165                 while ((ent = readdir(ifaces)) != NULL) {
 166                         if (DOT_OR_DOTDOT(ent->d_name))
 167                                 continue; /* . or .. */
 168                         if (tabs)
 169                                 printf("\t\t\t\t\t");
 170                         else
 171                                 tabs = 1;
 172                         printf("\t\t%s\n", ent->d_name);
 173                 }
 174                 closedir(ifaces);
 175         }
 176         if (!tabs)  /* bridge has no interfaces */
 177                 bb_putchar('\n');
 178         return 0;
 179 }
 180 #endif
 181
 182 #if ENABLE_FEATURE_BRCTL_FANCY
 183 static void write_uint(const char *name, const char *leaf, unsigned val)
 184 {
 185         char pathbuf[IFNAMSIZ + sizeof("/bridge/bridge_id") + 32];
 186         int fd, n;
 187
 188 #if IFNAMSIZ == 16
 189         sprintf(pathbuf, "%.16s/%s", name, leaf);
 190 #else
 191         sprintf(pathbuf, "%.*s/%s", (int)IFNAMSIZ, name, leaf);
 192 #endif
 193         fd = xopen(pathbuf, O_WRONLY);
 194         n = sprintf(filedata, "%u\n", val);
 195         if (write(fd, filedata, n) < 0)
 196                 bb_simple_perror_msg_and_die(name);
 197         /* So far all callers exit very soon after calling us.
 198          * Do not bother closing fd (unless debugging):
 199          */
 200         if (ENABLE_FEATURE_CLEAN_UP)
 201                 close(fd);
 202 }
 203
 204 struct fdb_entry {
 205         uint8_t mac_addr[6];
 206         uint8_t port_no;
 207         uint8_t is_local;
 208         uint32_t ageing_timer_value;
 209         uint8_t port_hi;
 210         uint8_t pad0;
 211         uint16_t unused;
 212 };
 213
 214 static int compare_fdbs(const void *_f0, const void *_f1)
 215 {
 216         const struct fdb_entry *f0 = _f0;
 217         const struct fdb_entry *f1 = _f1;
 218
 219         return memcmp(f0->mac_addr, f1->mac_addr, 6);
 220 }
 221
 222 static size_t read_bridge_forward_db(const char *name, struct fdb_entry **_fdb)
 223 {
 224         char pathbuf[IFNAMSIZ + sizeof("/brforward") + 8];
 225         struct fdb_entry *fdb;
 226         size_t nentries;
 227         int fd;
 228         ssize_t cc;
 229
 230 #if IFNAMSIZ == 16
 231         sprintf(pathbuf, "%.16s/brforward", name);
 232 #else
 233         sprintf(pathbuf, "%.*s/brforward", (int)IFNAMSIZ, name);
 234 #endif
 235         fd = open(pathbuf, O_RDONLY);
 236         if (fd < 0)
 237                 bb_error_msg_and_die("bridge %s does not exist", name);
 238
 239         fdb = NULL;
 240         nentries = 0;
 241         for (;;) {
 242                 fdb = xrealloc_vector(fdb, 4, nentries);
 243                 cc = full_read(fd, &fdb[nentries], sizeof(*fdb));
 244                 if (cc == 0) {
 245                         break;
 246                 }
 247                 if (cc != sizeof(*fdb)) {
 248                         bb_perror_msg_and_die("can't read bridge %s forward db", name);
 249                 }
 250                 ++nentries;
 251         }
 252
 253         if (ENABLE_FEATURE_CLEAN_UP)
 254                 close(fd);
 255
 256         qsort(fdb, nentries, sizeof(*fdb), compare_fdbs);
 257
 258         *_fdb = fdb;
 259         return nentries;
 260 }
 261
 262 static void show_bridge_macs(const char *name)
 263 {
 264         struct fdb_entry *fdb;
 265         size_t nentries;
 266         size_t i;
 267
 268         nentries = read_bridge_forward_db(name, &fdb);
 269
 270         printf("port no\tmac addr\t\tis local?\tageing timer\n");
 271         for (i = 0; i < nentries; ++i) {
 272                 const struct fdb_entry *f = &fdb[i];
 273                 unsigned tv_sec = f->ageing_timer_value / 100;
 274                 unsigned tv_csec = f->ageing_timer_value % 100;
 275                 printf("%3u\t"
 276                         "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x\t"
 277                         "%s\t\t"
 278                         "%4u.%.2u\n",
 279                         f->port_no,
 280                         f->mac_addr[0], f->mac_addr[1], f->mac_addr[2],
 281                         f->mac_addr[3], f->mac_addr[4], f->mac_addr[5],
 282                         (f->is_local ? "yes" : "no"),
 283                         tv_sec, tv_csec
 284                 );
 285         }
 286
 287         if (ENABLE_FEATURE_CLEAN_UP)
 288                 free(fdb);
 289 }
 290
 291 static void show_bridge_timer(const char *msg)
 292 {
 293         unsigned long long centisec = xstrtoull(filedata, 0);
 294         unsigned tv_sec = centisec / 100;
 295         unsigned tv_csec = centisec % 100;
 296         printf("%s%4u.%.2u", msg, tv_sec, tv_csec);
 297 }
 298
 299 static const char *show_bridge_state(unsigned state)
 300 {
 301         /* See linux/if_bridge.h, BR_STATE_ constants */
 302         static const char state_names[] ALIGN1 =
 303                 "disabled\0"    //BR_STATE_DISABLED   0
 304                 "listening\0"   //BR_STATE_LISTENING  1
 305                 "learning\0"    //BR_STATE_LEARNING   2
 306                 "forwarding\0"  //BR_STATE_FORWARDING 3
 307                 "blocking"      //BR_STATE_BLOCKING   4
 308         ;
 309         if (state < 5)
 310                 return nth_string(state_names, state);
 311         return utoa(state);
 312 }
 313
 314 static void printf_xstrtou(const char *fmt)
 315 {
 316         printf(fmt, xstrtou(filedata, 0));
 317 }
 318
 319 static void show_bridge_port(const char *name)
 320 {
 321         char pathbuf[IFNAMSIZ + sizeof("/brport/forward_delay_timer") + 8];
 322         char *sfx;
 323
 324 #if IFNAMSIZ == 16
 325         sfx = pathbuf + sprintf(pathbuf, "%.16s/brport/", name);
 326 #else
 327         sfx = pathbuf + sprintf(pathbuf, "%.*s/brport/", (int)IFNAMSIZ, name);
 328 #endif
 329
 330         strcpy(sfx, "port_no");
 331         read_file(pathbuf);
 332         printf("%s (%u)\n", name, xstrtou(filedata, 0));
 333
 334         strcpy(sfx + 5, "id"); // "port_id"
 335         read_file(pathbuf);
 336         printf_xstrtou(" port id\t\t%.4x");
 337
 338         strcpy(sfx, "state");
 339         read_file(pathbuf);
 340         printf("\t\t\tstate\t\t%15s\n", show_bridge_state(xstrtou(filedata, 0)));
 341
 342         strcpy(sfx, "designated_root");
 343         read_file(pathbuf);
 344         printf(" designated root\t%s", filedata);
 345
 346         strcpy(sfx, "path_cost");
 347         read_file(pathbuf);
 348         printf_xstrtou("\tpath cost\t\t%4u\n");
 349
 350         strcpy(sfx, "designated_bridge");
 351         read_file(pathbuf);
 352         printf(" designated bridge\t%s", filedata);
 353
 354         strcpy(sfx, "message_age_timer");
 355         read_file(pathbuf);
 356         show_bridge_timer("\tmessage age timer\t");
 357
 358         strcpy(sfx, "designated_port");
 359         read_file(pathbuf);
 360         printf_xstrtou("\n designated port\t%.4x");
 361
 362         strcpy(sfx, "forward_delay_timer");
 363         read_file(pathbuf);
 364         show_bridge_timer("\t\t\tforward delay timer\t");
 365
 366         strcpy(sfx, "designated_cost");
 367         read_file(pathbuf);
 368         printf_xstrtou("\n designated cost\t%4u");
 369
 370         strcpy(sfx, "hold_timer");
 371         read_file(pathbuf);
 372         show_bridge_timer("\t\t\thold timer\t\t");
 373
 374         printf("\n flags\t\t\t");
 375
 376         strcpy(sfx, "config_pending");
 377         read_file(pathbuf);
 378         if (!LONE_CHAR(filedata, '0'))
 379                 printf("CONFIG_PENDING ");
 380
 381         strcpy(sfx, "change_ack");
 382         read_file(pathbuf);
 383         if (!LONE_CHAR(filedata, '0'))
 384                 printf("TOPOLOGY_CHANGE_ACK ");
 385
 386         strcpy(sfx, "hairpin_mode");
 387         read_file(pathbuf);
 388         if (!LONE_CHAR(filedata, '0'))
 389                 printf_xstrtou("\n hairpin mode\t\t%4u");
 390
 391         printf("\n\n");
 392 }
 393
 394 static void show_bridge_stp(const char *name)
 395 {
 396         char pathbuf[IFNAMSIZ + sizeof("/bridge/topology_change_timer") + 8];
 397         char *sfx;
 398
 399 #if IFNAMSIZ == 16
 400         sfx = pathbuf + sprintf(pathbuf, "%.16s/bridge/", name);
 401 #else
 402         sfx = pathbuf + sprintf(pathbuf, "%.*s/bridge/", (int)IFNAMSIZ, name);
 403 #endif
 404
 405         strcpy(sfx, "bridge_id");
 406         if (read_file(pathbuf) < 0)
 407                 bb_error_msg_and_die("bridge %s does not exist", name);
 408
 409         printf("%s\n"
 410                 " bridge id\t\t%s", name, filedata);
 411
 412         strcpy(sfx, "root_id");
 413         read_file(pathbuf);
 414         printf("\n designated root\t%s", filedata);
 415
 416         strcpy(sfx + 5, "port"); // "root_port"
 417         read_file(pathbuf);
 418         printf_xstrtou("\n root port\t\t%4u\t\t\t");
 419
 420         strcpy(sfx + 6, "ath_cost"); // "root_path_cost"
 421         read_file(pathbuf);
 422         printf_xstrtou("path cost\t\t%4u\n");
 423
 424         strcpy(sfx, "max_age");
 425         read_file(pathbuf);
 426         show_bridge_timer(" max age\t\t");
 427         show_bridge_timer("\t\t\tbridge max age\t\t");
 428
 429         strcpy(sfx, "hello_time");
 430         read_file(pathbuf);
 431         show_bridge_timer("\n hello time\t\t");
 432         show_bridge_timer("\t\t\tbridge hello time\t");
 433
 434         strcpy(sfx, "forward_delay");
 435         read_file(pathbuf);
 436         show_bridge_timer("\n forward delay\t\t");
 437         show_bridge_timer("\t\t\tbridge forward delay\t");
 438
 439         strcpy(sfx, "ageing_time");
 440         read_file(pathbuf);
 441         show_bridge_timer("\n ageing time\t\t");
 442
 443         strcpy(sfx, "hello_timer");
 444         read_file(pathbuf);
 445         show_bridge_timer("\n hello timer\t\t");
 446
 447         strcpy(sfx, "tcn_timer");
 448         read_file(pathbuf);
 449         show_bridge_timer("\t\t\ttcn timer\t\t");
 450
 451         strcpy(sfx, "topology_change_timer");
 452         read_file(pathbuf);
 453         show_bridge_timer("\n topology change timer\t");
 454
 455         strcpy(sfx, "gc_timer");
 456         read_file(pathbuf);
 457         show_bridge_timer("\t\t\tgc timer\t\t");
 458
 459         printf("\n flags\t\t\t");
 460
 461         strcpy(sfx, "topology_change");
 462         read_file(pathbuf);
 463         if (!LONE_CHAR(filedata, '0'))
 464                 printf("TOPOLOGY_CHANGE ");
 465
 466         strcpy(sfx, "topology_change_detected");
 467         read_file(pathbuf);
 468         if (!LONE_CHAR(filedata, '0'))
 469                 printf("TOPOLOGY_CHANGE_DETECTED ");
 470         printf("\n\n\n");
 471
 472         /* Show bridge ports */
 473         {
 474                 DIR *ifaces;
 475
 476                 /* sfx points past "BR/bridge/", turn it into "BR/brif": */
 477                 sfx[-4] = 'f'; sfx[-3] = '\0';
 478                 ifaces = opendir(pathbuf);
 479                 if (ifaces) {
 480                         struct dirent *ent;
 481                         while ((ent = readdir(ifaces)) != NULL) {
 482                                 if (DOT_OR_DOTDOT(ent->d_name))
 483                                         continue; /* . or .. */
 484                                 show_bridge_port(ent->d_name);
 485                         }
 486                         if (ENABLE_FEATURE_CLEAN_UP)
 487                                 closedir(ifaces);
 488                 }
 489         }
 490 }
 491 #endif
 492
 493 int brctl_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 494 int brctl_main(int argc UNUSED_PARAM, char **argv)
 495 {
 496         static const char keywords[] ALIGN1 =
 497                 "addbr\0" "delbr\0" "addif\0" "delif\0"
 498         IF_FEATURE_BRCTL_FANCY(
 499                 "stp\0"
 500                 "showstp\0"
 501                 "setageing\0" "setfd\0" "sethello\0" "setmaxage\0"
 502                 "setpathcost\0" "setportprio\0"
 503                 "setbridgeprio\0"
 504                 "showmacs\0"
 505         )
 506         IF_FEATURE_BRCTL_SHOW("show\0");
 507         enum { ARG_addbr = 0, ARG_delbr, ARG_addif, ARG_delif
 508                 IF_FEATURE_BRCTL_FANCY(,
 509                         ARG_stp,
 510                         ARG_showstp,
 511                         ARG_setageing, ARG_setfd, ARG_sethello, ARG_setmaxage,
 512                         ARG_setpathcost, ARG_setportprio,
 513                         ARG_setbridgeprio,
 514                         ARG_showmacs
 515                 )
 516                 IF_FEATURE_BRCTL_SHOW(, ARG_show)
 517         };
 518         int key;
 519         char *br;
 520
 521         argv++;
 522         if (!*argv) {
 523                 /* bare "brctl" shows --help */
 524                 bb_show_usage();
 525         }
 526
 527         xchdir("/sys/class/net");
 528
 529         key = index_in_strings(keywords, *argv);
 530         if (key == -1) /* no match found in keywords array, bail out. */
 531                 bb_error_msg_and_die(bb_msg_invalid_arg_to, *argv, applet_name);
 532         argv++;
 533
 534 #if ENABLE_FEATURE_BRCTL_SHOW
 535         if (key == ARG_show) { /* show [BR]... */
 536                 DIR *net;
 537                 struct dirent *ent;
 538                 int need_hdr = 1;
 539                 int exitcode = EXIT_SUCCESS;
 540
 541                 if (*argv) {
 542                         /* "show BR1 BR2 BR3" */
 543                         do {
 544                                 if (show_bridge(*argv, need_hdr) >= 0) {
 545                                         need_hdr = 0;
 546                                 } else {
 547                                         bb_error_msg("bridge %s does not exist", *argv);
 548 //TODO: if device exists, but is not a BR, brctl from bridge-utils 1.6
 549 //says this instead: "device eth0 is not a bridge"
 550                                         exitcode = EXIT_FAILURE;
 551                                 }
 552                         } while (*++argv != NULL);
 553                         return exitcode;
 554                 }
 555
 556                 /* "show" (if no ifaces, shows nothing, not even header) */
 557                 net = xopendir(".");
 558                 while ((ent = readdir(net)) != NULL) {
 559                         if (DOT_OR_DOTDOT(ent->d_name))
 560                                 continue; /* . or .. */
 561                         if (show_bridge(ent->d_name, need_hdr) >= 0)
 562                                 need_hdr = 0;
 563                 }
 564                 if (ENABLE_FEATURE_CLEAN_UP)
 565                         closedir(net);
 566                 return exitcode;
 567         }
 568 #endif
 569
 570         if (!*argv) /* All of the below need at least one argument */
 571                 bb_show_usage();
 572
 573         br = *argv++;
 574
 575         if (key == ARG_addbr || key == ARG_delbr) {
 576                 /* brctl from bridge-utils 1.6 still uses ioctl
 577                  * for SIOCBRADDBR / SIOCBRDELBR, not /sys accesses
 578                  */
 579                 int fd = xsocket(AF_INET, SOCK_STREAM, 0);
 580                 ioctl_or_perror_and_die(fd,
 581                         key == ARG_addbr ? SIOCBRADDBR : SIOCBRDELBR,
 582                         br, "bridge %s", br
 583                 );
 584                 //close(fd);
 585                 //goto done;
 586                 /* bridge-utils 1.6 simply ignores trailing args:
 587                  * "brctl addbr BR1 ARGS" ignores ARGS
 588                  */
 589                 if (ENABLE_FEATURE_CLEAN_UP)
 590                         close(fd);
 591                 return EXIT_SUCCESS;
 592         }
 593
 594         if (key == ARG_showmacs) {
 595                 show_bridge_macs(br);
 596                 return EXIT_SUCCESS;
 597         }
 598         if (key == ARG_showstp) {
 599                 show_bridge_stp(br);
 600                 return EXIT_SUCCESS;
 601         }
 602
 603         if (!*argv) /* All of the below need at least two arguments */
 604                 bb_show_usage();
 605
 606 #if ENABLE_FEATURE_BRCTL_FANCY
 607         if (key == ARG_stp) {
 608                 static const char no_yes[] ALIGN1 =
 609                         "0\0" "off\0" "n\0" "no\0"   /* 0 .. 3 */
 610                         "1\0" "on\0"  "y\0" "yes\0"; /* 4 .. 7 */
 611                 int onoff = index_in_strings(no_yes, *argv);
 612                 if (onoff < 0)
 613                         bb_error_msg_and_die(bb_msg_invalid_arg_to, *argv, applet_name);
 614                 onoff = (unsigned)onoff / 4;
 615                 write_uint(br, "bridge/stp_state", onoff);
 616                 return EXIT_SUCCESS;
 617         }
 618
 619         if ((unsigned)(key - ARG_setageing) < 4) { /* time related ops */
 620                 /* setageing BR N: "N*100\n" to /sys/class/net/BR/bridge/ageing_time
 621                  * setfd BR N:     "N*100\n" to /sys/class/net/BR/bridge/forward_delay
 622                  * sethello BR N:  "N*100\n" to /sys/class/net/BR/bridge/hello_time
 623                  * setmaxage BR N: "N*100\n" to /sys/class/net/BR/bridge/max_age
 624                  */
 625                 write_uint(br,
 626                         nth_string(
 627                                 "bridge/ageing_time"  "\0" /* ARG_setageing */
 628                                 "bridge/forward_delay""\0" /* ARG_setfd     */
 629                                 "bridge/hello_time"   "\0" /* ARG_sethello  */
 630                                 "bridge/max_age",          /* ARG_setmaxage */
 631                                 key - ARG_setageing
 632                         ),
 633                         str_to_jiffies(*argv)
 634                 );
 635                 return EXIT_SUCCESS;
 636         }
 637
 638         if (key == ARG_setbridgeprio) {
 639                 write_uint(br, "bridge/priority", xatoi_positive(*argv));
 640                 return EXIT_SUCCESS;
 641         }
 642
 643         if (key == ARG_setpathcost
 644          || key == ARG_setportprio
 645         ) {
 646                 if (!argv[1])
 647                         bb_show_usage();
 648                 /* BR is not used (and ignored!) for these commands:
 649                  * "setpathcost BR PORT N" writes "N\n" to
 650                  * /sys/class/net/PORT/brport/path_cost
 651                  * "setportprio BR PORT N" writes "N\n" to
 652                  * /sys/class/net/PORT/brport/priority
 653                  */
 654                 write_uint(argv[0],
 655                         nth_string(
 656                                 "brport/path_cost" "\0" /* ARG_setpathcost */
 657                                 "brport/priority",      /* ARG_setportprio */
 658                                 key - ARG_setpathcost
 659                         ),
 660                         xatoi_positive(argv[1])
 661                 );
 662                 return EXIT_SUCCESS;
 663         }
 664 #endif
 665         /* always true: if (key == ARG_addif || key == ARG_delif) */ {
 666                 struct ifreq ifr;
 667                 int fd = xsocket(AF_INET, SOCK_STREAM, 0);
 668
 669                 strncpy_IFNAMSIZ(ifr.ifr_name, br);
 670                 ifr.ifr_ifindex = if_nametoindex(*argv);
 671                 if (ifr.ifr_ifindex == 0) {
 672                         bb_perror_msg_and_die("iface %s", *argv);
 673                 }
 674                 ioctl_or_perror_and_die(fd,
 675                         key == ARG_addif ? SIOCBRADDIF : SIOCBRDELIF,
 676                         &ifr, "bridge %s", br
 677                 );
 678                 if (ENABLE_FEATURE_CLEAN_UP)
 679                         close(fd);
 680         }
 681
 682         return EXIT_SUCCESS;
 683 }