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 Fischer
   6  *
   7  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
   8  */
   9 #include "libbb.h"
  10 #include <linux/sockios.h>
  11 #include <net/if.h>
  12
  13 #ifdef ENABLE_FEATURE_BRCTL_SHOW
  14 #error Remove these
  15 #endif
  16 #define ENABLE_FEATURE_BRCTL_SHOW 0
  17 #define USE_FEATURE_BRCTL_SHOW(...)
  18
  19
  20 /* Fancy diagnostics -- printing add/del -- costs 49 bytes. */
  21 #if 0
  22 #define BRCTL_VERBOSE(...) __VA_ARGS__
  23 #else
  24 #define BRCTL_VERBOSE(...)
  25 #endif
  26
  27 int brctl_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  28 int brctl_main(int argc, char **argv)
  29 {
  30         int fd;
  31         static const char keywords[] ALIGN1 =
  32                 "addbr\0" "delbr\0" "addif\0" "delif\0"
  33                 USE_FEATURE_BRCTL_SHOW("show\0");
  34         enum { ARG_addbr = 1, ARG_delbr, ARG_addif, ARG_delif
  35                   USE_FEATURE_BRCTL_SHOW(, ARG_show) };
  36         smalluint key;
  37         static char info[] = BRCTL_VERBOSE("%s ")"bridge %s\0 iface %s";
  38         char *br;
  39
  40         argv++;
  41         while (*argv) {
  42                 BRCTL_VERBOSE(char *op;)
  43
  44                 key = index_in_strings(keywords, *argv) + 1;
  45                 if (key == 0) /* no match found in keywords array, bail out. */
  46                         bb_error_msg_and_die(bb_msg_invalid_arg, *argv, applet_name);
  47                 argv++;
  48 #if ENABLE_FEATURE_BRCTL_SHOW
  49                 if (key == ARG_show) { /* show */
  50                         ;
  51                 }
  52 #endif
  53                 BRCTL_VERBOSE(op = (char*)((key % 2) ? "add" : "del");)
  54                 fd = xsocket(AF_INET, SOCK_STREAM, 0);
  55                 br = *(argv++);
  56
  57                 if (key < 3) { /* addbr or delbr */
  58                         if (ioctl(fd, key == ARG_addbr ? SIOCBRADDBR : SIOCBRDELBR, br) < 0)
  59                         {
  60                                 info[9 BRCTL_VERBOSE(+3)] = '\0';
  61                                 bb_perror_msg_and_die(info, BRCTL_VERBOSE(op,) br);
  62                         }
  63                 }
  64                 if (key > 2) { /* addif or delif */
  65                         struct ifreq ifr;
  66                         char *brif;
  67
  68                         if (!*argv)
  69                                 bb_show_usage();
  70                         brif = *(argv++);
  71
  72                         if (!(ifr.ifr_ifindex = if_nametoindex(brif))) {
  73                                 bb_perror_msg_and_die(info+11 BRCTL_VERBOSE(+3), brif);
  74                         }
  75                         safe_strncpy(ifr.ifr_name, br, IFNAMSIZ);
  76                         if (ioctl(fd,
  77                                           key == ARG_addif ? SIOCBRADDIF : SIOCBRDELIF, &ifr) < 0) {
  78                                 info[9 BRCTL_VERBOSE(+3)] = ',';
  79                                 bb_perror_msg_and_die (info, BRCTL_VERBOSE(op,) br, brif);
  80                         }
  81                 }
  82                 if (ENABLE_FEATURE_CLEAN_UP)
  83                         close(fd);
  84         }
  85         return EXIT_SUCCESS;
  86 }