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 /* This applet currently uses only the ioctl interface and no sysfs at all.
  10  * At the time of this writing this was considered a feature.
  11  */
  12 #include "libbb.h"
  13 #include <linux/sockios.h>
  14 #include <net/if.h>
  15
  16 #ifdef ENABLE_FEATURE_BRCTL_SHOW
  17 #error Remove these
  18 #endif
  19 #define ENABLE_FEATURE_BRCTL_SHOW 0
  20 #define USE_FEATURE_BRCTL_SHOW(...)
  21 #if 0
  22 #define ENABLE_FEATURE_BRCTL_FANCY 0
  23 #if ENABLE_FEATURE_BRCTL_FANCY
  24 #define USE_FEATURE_BRCTL_FANCY(...) __VA_ARGS__
  25 #else
  26 #define USE_FEATURE_BRCTL_FANCY(...)
  27 #endif
  28 #endif
  29 #if ENABLE_FEATURE_BRCTL_FANCY
  30 #include <linux/if_bridge.h>
  31 /* FIXME: These 4 funcs are not really clean and could be improved */
  32 static inline ALWAYS_INLINE void strtotimeval(struct timeval *tv,
  33                                                                                           const char *time_str)
  34 {
  35         double secs;
  36         if (sscanf(time_str, "%lf", &secs) != 1)
  37                 bb_error_msg_and_die (bb_msg_invalid_arg, time_str, "timespec");
  38         tv->tv_sec = secs;
  39         tv->tv_usec = 1000000 * (secs - tv->tv_sec);
  40 }
  41
  42 static inline ALWAYS_INLINE unsigned long __tv_to_jiffies(const struct timeval *tv)
  43 {
  44         unsigned long long jif;
  45
  46         jif = 1000000ULL * tv->tv_sec + tv->tv_usec;
  47
  48         return jif/10000;
  49 }
  50 # ifdef UNUSED && 00
  51 static void __jiffies_to_tv(struct timeval *tv, unsigned long jiffies)
  52 {
  53         unsigned long long tvusec;
  54
  55         tvusec = 10000ULL*jiffies;
  56         tv->tv_sec = tvusec/1000000;
  57         tv->tv_usec = tvusec - 1000000 * tv->tv_sec;
  58 }
  59 # endif
  60 static unsigned long str_to_jiffies(const char *time_str)
  61 {
  62         struct timeval tv;
  63         strtotimeval(&tv, time_str);
  64         return __tv_to_jiffies(&tv);
  65 }
  66 #endif
  67
  68
  69 int brctl_main(int argc ATTRIBUTE_UNUSED, char **argv) MAIN_EXTERNALLY_VISIBLE;
  70 int brctl_main(int argc ATTRIBUTE_UNUSED, char **argv)
  71 {
  72         int fd;
  73         static const char keywords[] ALIGN1 =
  74                 "addbr\0" "delbr\0" "addif\0" "delif\0"
  75         USE_FEATURE_BRCTL_FANCY(
  76                 "setageing\0" "setfd\0" "sethello\0" "setmaxage\0"
  77                 "setpathcost\0" "setportprio\0" "setbridgeprio\0"
  78                 "stp\0"
  79         )
  80                 USE_FEATURE_BRCTL_SHOW("showmacs\0" "show\0");
  81         enum { ARG_addbr = 0, ARG_delbr, ARG_addif, ARG_delif
  82                 USE_FEATURE_BRCTL_FANCY(,
  83                    ARG_setageing, ARG_setfd, ARG_sethello, ARG_setmaxage,
  84                    ARG_setpathcost, ARG_setportprio, ARG_setbridgeprio,
  85                    ARG_stp
  86                 )
  87                   USE_FEATURE_BRCTL_SHOW(, ARG_showmacs, ARG_show) };
  88         smallint key;
  89         struct ifreq ifr;
  90         static char info[] = "bridge %s\0 iface %s";
  91         char *br;
  92
  93         argv++;
  94         while (*argv) {
  95                 key = index_in_strings(keywords, *argv);
  96                 if (key == -1) /* no match found in keywords array, bail out. */
  97                         bb_error_msg_and_die(bb_msg_invalid_arg, *argv, applet_name);
  98                 argv++;
  99 #if ENABLE_FEATURE_BRCTL_SHOW
 100                 if (key == ARG_show) { /* show */
 101                         goto out; /* FIXME: implement me! :) */
 102                 }
 103 #endif
 104                 fd = xsocket(AF_INET, SOCK_STREAM, 0);
 105                 br = *(argv++);
 106
 107                 if (key == ARG_addbr || key == ARG_delbr) { /* addbr or delbr */
 108                         ioctl_or_perror_and_die(fd,
 109                                                                 key == ARG_addbr ? SIOCBRADDBR : SIOCBRDELBR,
 110                                                                 br, info, br);
 111                         goto done;
 112                 }
 113                 if (!*argv) /* all but 'show' need at least one argument */
 114                         bb_show_usage();
 115                 safe_strncpy(ifr.ifr_name, br, IFNAMSIZ);
 116                 if (key == ARG_addif || key == ARG_delif) { /* addif or delif */
 117                         char *brif;
 118
 119                         brif = *(argv++);
 120                         if (!(ifr.ifr_ifindex = if_nametoindex(brif))) {
 121                                 bb_perror_msg_and_die(info+11, brif);
 122                         }
 123                         ioctl_or_perror_and_die(fd,
 124                                                                   key == ARG_addif ? SIOCBRADDIF : SIOCBRDELIF,
 125                                                                   &ifr, info, br);
 126                 }
 127 #if ENABLE_FEATURE_BRCTL_FANCY
 128                 if (key - ARG_delif < 5) { /* time related ops */
 129                         unsigned long op = (key == ARG_setageing) ? BRCTL_SET_AGEING_TIME :
 130                                                         (key == ARG_setfd) ? BRCTL_SET_BRIDGE_FORWARD_DELAY:
 131                                                         (key == ARG_sethello) ? BRCTL_SET_BRIDGE_HELLO_TIME:
 132                                                         (key == ARG_setmaxage) ? BRCTL_SET_BRIDGE_MAX_AGE :
 133                                                         -1/*will never be used */;
 134                         unsigned long jiff = str_to_jiffies (*(argv++));
 135                         unsigned long args[4] = {op, jiff, 0, 0};
 136                         ifr.ifr_data = (char *) &args;
 137                         xioctl(fd, SIOCDEVPRIVATE, &ifr);
 138                 }
 139 #endif
 140  done:
 141                 if (ENABLE_FEATURE_CLEAN_UP)
 142                         close(fd);
 143         }
 144  out:
 145         return EXIT_SUCCESS;
 146 }