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 tarball for details.
  11  */
  12 /* This applet currently uses only the ioctl interface and no sysfs at all.
  13  * At the time of this writing this was considered a feature.
  14  */
  15 #include "libbb.h"
  16 #include <linux/sockios.h>
  17 #include <net/if.h>
  18
  19 /* Maximum number of ports supported per bridge interface.  */
  20 #ifndef MAX_PORTS
  21 #define MAX_PORTS 32
  22 #endif
  23
  24 /* Use internal number parsing and not the "exact" conversion.  */
  25 /* #define BRCTL_USE_INTERNAL 0 */ /* use exact conversion */
  26 #define BRCTL_USE_INTERNAL 1
  27
  28 #if ENABLE_FEATURE_BRCTL_FANCY
  29 #include <linux/if_bridge.h>
  30
  31 /* FIXME: These 4 funcs are not really clean and could be improved */
  32 static ALWAYS_INLINE void strtotimeval(struct timeval *tv,
  33                 const char *time_str)
  34 {
  35         double secs;
  36 #if BRCTL_USE_INTERNAL
  37         secs = /*bb_*/strtod(time_str, NULL);
  38         if (!secs)
  39 #else
  40         if (sscanf(time_str, "%lf", &secs) != 1)
  41 #endif
  42                 bb_error_msg_and_die (bb_msg_invalid_arg, time_str, "timespec");
  43         tv->tv_sec = secs;
  44         tv->tv_usec = 1000000 * (secs - tv->tv_sec);
  45 }
  46
  47 static ALWAYS_INLINE unsigned long __tv_to_jiffies(const struct timeval *tv)
  48 {
  49         unsigned long long jif;
  50
  51         jif = 1000000ULL * tv->tv_sec + tv->tv_usec;
  52
  53         return jif/10000;
  54 }
  55 # if 0
  56 static void __jiffies_to_tv(struct timeval *tv, unsigned long jiffies)
  57 {
  58         unsigned long long tvusec;
  59
  60         tvusec = 10000ULL*jiffies;
  61         tv->tv_sec = tvusec/1000000;
  62         tv->tv_usec = tvusec - 1000000 * tv->tv_sec;
  63 }
  64 # endif
  65 static unsigned long str_to_jiffies(const char *time_str)
  66 {
  67         struct timeval tv;
  68         strtotimeval(&tv, time_str);
  69         return __tv_to_jiffies(&tv);
  70 }
  71
  72 static void arm_ioctl(unsigned long *args,
  73                 unsigned long arg0, unsigned long arg1, unsigned long arg2)
  74 {
  75         args[0] = arg0;
  76         args[1] = arg1;
  77         args[2] = arg2;
  78         args[3] = 0;
  79 }
  80 #endif
  81
  82
  83 int brctl_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  84 int brctl_main(int argc UNUSED_PARAM, char **argv)
  85 {
  86         static const char keywords[] ALIGN1 =
  87                 "addbr\0" "delbr\0" "addif\0" "delif\0"
  88         USE_FEATURE_BRCTL_FANCY(
  89                 "stp\0"
  90                 "setageing\0" "setfd\0" "sethello\0" "setmaxage\0"
  91                 "setpathcost\0" "setportprio\0" "setbridgeprio\0"
  92         )
  93         USE_FEATURE_BRCTL_SHOW("showmacs\0" "show\0");
  94
  95         enum { ARG_addbr = 0, ARG_delbr, ARG_addif, ARG_delif
  96                 USE_FEATURE_BRCTL_FANCY(,
  97                    ARG_stp,
  98                    ARG_setageing, ARG_setfd, ARG_sethello, ARG_setmaxage,
  99                    ARG_setpathcost, ARG_setportprio, ARG_setbridgeprio
 100                 )
 101                 USE_FEATURE_BRCTL_SHOW(, ARG_showmacs, ARG_show)
 102         };
 103
 104         int fd;
 105         smallint key;
 106         struct ifreq ifr;
 107         char *br, *brif;
 108
 109         argv++;
 110         while (*argv) {
 111 #if ENABLE_FEATURE_BRCTL_FANCY
 112                 int ifidx[MAX_PORTS];
 113                 unsigned long args[4];
 114                 ifr.ifr_data = (char *) &args;
 115 #endif
 116
 117                 key = index_in_strings(keywords, *argv);
 118                 if (key == -1) /* no match found in keywords array, bail out. */
 119                         bb_error_msg_and_die(bb_msg_invalid_arg, *argv, applet_name);
 120                 argv++;
 121                 fd = xsocket(AF_INET, SOCK_STREAM, 0);
 122
 123 #if ENABLE_FEATURE_BRCTL_SHOW
 124                 if (key == ARG_show) { /* show */
 125                         char brname[IFNAMSIZ];
 126                         int bridx[MAX_PORTS];
 127                         int i, num;
 128                         arm_ioctl(args, BRCTL_GET_BRIDGES,
 129                                                 (unsigned long) bridx, MAX_PORTS);
 130                         num = xioctl(fd, SIOCGIFBR, args);
 131                         printf("bridge name\tbridge id\t\tSTP enabled\tinterfaces\n");
 132                         for (i = 0; i < num; i++) {
 133                                 char ifname[IFNAMSIZ];
 134                                 int j, tabs;
 135                                 struct __bridge_info bi;
 136                                 unsigned char *x;
 137
 138                                 if (!if_indextoname(bridx[i], brname))
 139                                         bb_perror_msg_and_die("can't get bridge name for index %d", i);
 140                                 strncpy_IFNAMSIZ(ifr.ifr_name, brname);
 141
 142                                 arm_ioctl(args, BRCTL_GET_BRIDGE_INFO,
 143                                                         (unsigned long) &bi, 0);
 144                                 xioctl(fd, SIOCDEVPRIVATE, &ifr);
 145                                 printf("%s\t\t", brname);
 146
 147                                 /* print bridge id */
 148                                 x = (unsigned char *) &bi.bridge_id;
 149                                 for (j = 0; j < 8; j++) {
 150                                         printf("%.2x", x[j]);
 151                                         if (j == 1)
 152                                                 bb_putchar('.');
 153                                 }
 154                                 printf(bi.stp_enabled ? "\tyes" : "\tno");
 155
 156                                 /* print interface list */
 157                                 arm_ioctl(args, BRCTL_GET_PORT_LIST,
 158                                                         (unsigned long) ifidx, MAX_PORTS);
 159                                 xioctl(fd, SIOCDEVPRIVATE, &ifr);
 160                                 tabs = 0;
 161                                 for (j = 0; j < MAX_PORTS; j++) {
 162                                         if (!ifidx[j])
 163                                                 continue;
 164                                         if (!if_indextoname(ifidx[j], ifname))
 165                                                 bb_perror_msg_and_die("can't get interface name for index %d", j);
 166                                         if (tabs)
 167                                                 printf("\t\t\t\t\t");
 168                                         else
 169                                                 tabs = 1;
 170                                         printf("\t\t%s\n", ifname);
 171                                 }
 172                                 if (!tabs)      /* bridge has no interfaces */
 173                                         bb_putchar('\n');
 174                         }
 175                         goto done;
 176                 }
 177 #endif
 178
 179                 if (!*argv) /* all but 'show' need at least one argument */
 180                         bb_show_usage();
 181
 182                 br = *argv++;
 183
 184                 if (key == ARG_addbr || key == ARG_delbr) { /* addbr or delbr */
 185                         ioctl_or_perror_and_die(fd,
 186                                         key == ARG_addbr ? SIOCBRADDBR : SIOCBRDELBR,
 187                                         br, "bridge %s", br);
 188                         goto done;
 189                 }
 190
 191                 if (!*argv) /* all but 'addif/delif' need at least two arguments */
 192                         bb_show_usage();
 193
 194                 strncpy_IFNAMSIZ(ifr.ifr_name, br);
 195                 if (key == ARG_addif || key == ARG_delif) { /* addif or delif */
 196                         brif = *argv;
 197                         ifr.ifr_ifindex = if_nametoindex(brif);
 198                         if (!ifr.ifr_ifindex) {
 199                                 bb_perror_msg_and_die("iface %s", brif);
 200                         }
 201                         ioctl_or_perror_and_die(fd,
 202                                         key == ARG_addif ? SIOCBRADDIF : SIOCBRDELIF,
 203                                         &ifr, "bridge %s", br);
 204                         goto done_next_argv;
 205                 }
 206 #if ENABLE_FEATURE_BRCTL_FANCY
 207                 if (key == ARG_stp) { /* stp */
 208                         /* FIXME: parsing yes/y/on/1 versus no/n/off/0 is too involved */
 209                         arm_ioctl(args, BRCTL_SET_BRIDGE_STP_STATE,
 210                                           (unsigned)(**argv - '0'), 0);
 211                         goto fire;
 212                 }
 213                 if ((unsigned)(key - ARG_setageing) < 4) { /* time related ops */
 214                         static const uint8_t ops[] ALIGN1 = {
 215                                 BRCTL_SET_AGEING_TIME,          /* ARG_setageing */
 216                                 BRCTL_SET_BRIDGE_FORWARD_DELAY, /* ARG_setfd     */
 217                                 BRCTL_SET_BRIDGE_HELLO_TIME,    /* ARG_sethello  */
 218                                 BRCTL_SET_BRIDGE_MAX_AGE        /* ARG_setmaxage */
 219                         };
 220                         arm_ioctl(args, ops[key - ARG_setageing], str_to_jiffies(*argv), 0);
 221                         goto fire;
 222                 }
 223                 if (key == ARG_setpathcost
 224                  || key == ARG_setportprio
 225                  || key == ARG_setbridgeprio
 226                 ) {
 227                         static const uint8_t ops[] ALIGN1 = {
 228                                 BRCTL_SET_PATH_COST,      /* ARG_setpathcost   */
 229                                 BRCTL_SET_PORT_PRIORITY,  /* ARG_setportprio   */
 230                                 BRCTL_SET_BRIDGE_PRIORITY /* ARG_setbridgeprio */
 231                         };
 232                         int port = -1;
 233                         unsigned arg1, arg2;
 234
 235                         if (key != ARG_setbridgeprio) {
 236                                 /* get portnum */
 237                                 unsigned i;
 238
 239                                 port = if_nametoindex(*argv++);
 240                                 if (!port)
 241                                         bb_error_msg_and_die(bb_msg_invalid_arg, *argv, "port");
 242                                 memset(ifidx, 0, sizeof ifidx);
 243                                 arm_ioctl(args, BRCTL_GET_PORT_LIST, (unsigned long)ifidx,
 244                                                   MAX_PORTS);
 245                                 xioctl(fd, SIOCDEVPRIVATE, &ifr);
 246                                 for (i = 0; i < MAX_PORTS; i++) {
 247                                         if (ifidx[i] == port) {
 248                                                 port = i;
 249                                                 break;
 250                                         }
 251                                 }
 252                         }
 253                         arg1 = port;
 254                         arg2 = xatoi_u(*argv);
 255                         if (key == ARG_setbridgeprio) {
 256                                 arg1 = arg2;
 257                                 arg2 = 0;
 258                         }
 259                         arm_ioctl(args, ops[key - ARG_setpathcost], arg1, arg2);
 260                 }
 261  fire:
 262                 /* Execute the previously set command */
 263                 xioctl(fd, SIOCDEVPRIVATE, &ifr);
 264 #endif
 265  done_next_argv:
 266                 argv++;
 267  done:
 268                 close(fd);
 269         }
 270
 271         return EXIT_SUCCESS;
 272 }