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 /* 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
  16 //usage:#define brctl_trivial_usage
  17 //usage:       "COMMAND [BRIDGE [INTERFACE]]"
  18 //usage:#define brctl_full_usage "\n\n"
  19 //usage:       "Manage ethernet bridges\n"
  20 //usage:     "\nCommands:"
  21 //usage:        IF_FEATURE_BRCTL_SHOW(
  22 //usage:     "\n        show                    Show a list of bridges"
  23 //usage:        )
  24 //usage:     "\n        addbr BRIDGE            Create BRIDGE"
  25 //usage:     "\n        delbr BRIDGE            Delete BRIDGE"
  26 //usage:     "\n        addif BRIDGE IFACE      Add IFACE to BRIDGE"
  27 //usage:     "\n        delif BRIDGE IFACE      Delete IFACE from BRIDGE"
  28 //usage:        IF_FEATURE_BRCTL_FANCY(
  29 //usage:     "\n        setageing BRIDGE TIME           Set ageing time"
  30 //usage:     "\n        setfd BRIDGE TIME               Set bridge forward delay"
  31 //usage:     "\n        sethello BRIDGE TIME            Set hello time"
  32 //usage:     "\n        setmaxage BRIDGE TIME           Set max message age"
  33 //usage:     "\n        setpathcost BRIDGE COST         Set path cost"
  34 //usage:     "\n        setportprio BRIDGE PRIO         Set port priority"
  35 //usage:     "\n        setbridgeprio BRIDGE PRIO       Set bridge priority"
  36 //usage:     "\n        stp BRIDGE [1/yes/on|0/no/off]  STP on/off"
  37 //usage:        )
  38
  39 #include "libbb.h"
  40 #include <linux/sockios.h>
  41 #include <net/if.h>
  42
  43 #ifndef SIOCBRADDBR
  44 # define SIOCBRADDBR BRCTL_ADD_BRIDGE
  45 #endif
  46 #ifndef SIOCBRDELBR
  47 # define SIOCBRDELBR BRCTL_DEL_BRIDGE
  48 #endif
  49 #ifndef SIOCBRADDIF
  50 # define SIOCBRADDIF BRCTL_ADD_IF
  51 #endif
  52 #ifndef SIOCBRDELIF
  53 # define SIOCBRDELIF BRCTL_DEL_IF
  54 #endif
  55
  56
  57 /* Maximum number of ports supported per bridge interface.  */
  58 #ifndef MAX_PORTS
  59 # define MAX_PORTS 32
  60 #endif
  61
  62 /* Use internal number parsing and not the "exact" conversion.  */
  63 /* #define BRCTL_USE_INTERNAL 0 */ /* use exact conversion */
  64 #define BRCTL_USE_INTERNAL 1
  65
  66 #if ENABLE_FEATURE_BRCTL_FANCY
  67 # include <linux/if_bridge.h>
  68
  69 /* FIXME: These 4 funcs are not really clean and could be improved */
  70 static ALWAYS_INLINE void bb_strtotimeval(struct timeval *tv,
  71                 const char *time_str)
  72 {
  73         double secs;
  74 # if BRCTL_USE_INTERNAL
  75         char *endptr;
  76         secs = /*bb_*/strtod(time_str, &endptr);
  77         if (endptr == time_str)
  78 # else
  79         if (sscanf(time_str, "%lf", &secs) != 1)
  80 # endif
  81                 bb_error_msg_and_die(bb_msg_invalid_arg, time_str, "timespec");
  82         tv->tv_sec = secs;
  83         tv->tv_usec = 1000000 * (secs - tv->tv_sec);
  84 }
  85
  86 static ALWAYS_INLINE unsigned long tv_to_jiffies(const struct timeval *tv)
  87 {
  88         unsigned long long jif;
  89
  90         jif = 1000000ULL * tv->tv_sec + tv->tv_usec;
  91
  92         return jif/10000;
  93 }
  94 # if 0
  95 static void jiffies_to_tv(struct timeval *tv, unsigned long jiffies)
  96 {
  97         unsigned long long tvusec;
  98
  99         tvusec = 10000ULL*jiffies;
 100         tv->tv_sec = tvusec/1000000;
 101         tv->tv_usec = tvusec - 1000000 * tv->tv_sec;
 102 }
 103 # endif
 104 static unsigned long str_to_jiffies(const char *time_str)
 105 {
 106         struct timeval tv;
 107         bb_strtotimeval(&tv, time_str);
 108         return tv_to_jiffies(&tv);
 109 }
 110
 111 static void arm_ioctl(unsigned long *args,
 112                 unsigned long arg0, unsigned long arg1, unsigned long arg2)
 113 {
 114         args[0] = arg0;
 115         args[1] = arg1;
 116         args[2] = arg2;
 117         args[3] = 0;
 118 }
 119 #endif
 120
 121
 122 int brctl_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 123 int brctl_main(int argc UNUSED_PARAM, char **argv)
 124 {
 125         static const char keywords[] ALIGN1 =
 126                 "addbr\0" "delbr\0" "addif\0" "delif\0"
 127         IF_FEATURE_BRCTL_FANCY(
 128                 "stp\0"
 129                 "setageing\0" "setfd\0" "sethello\0" "setmaxage\0"
 130                 "setpathcost\0" "setportprio\0" "setbridgeprio\0"
 131         )
 132         IF_FEATURE_BRCTL_SHOW("show\0");
 133
 134         enum { ARG_addbr = 0, ARG_delbr, ARG_addif, ARG_delif
 135                 IF_FEATURE_BRCTL_FANCY(,
 136                         ARG_stp,
 137                         ARG_setageing, ARG_setfd, ARG_sethello, ARG_setmaxage,
 138                         ARG_setpathcost, ARG_setportprio, ARG_setbridgeprio
 139                 )
 140                 IF_FEATURE_BRCTL_SHOW(, ARG_show)
 141         };
 142
 143         int fd;
 144         smallint key;
 145         struct ifreq ifr;
 146         char *br, *brif;
 147
 148         argv++;
 149         while (*argv) {
 150 #if ENABLE_FEATURE_BRCTL_FANCY
 151                 int ifidx[MAX_PORTS];
 152                 unsigned long args[4];
 153                 ifr.ifr_data = (char *) &args;
 154 #endif
 155
 156                 key = index_in_strings(keywords, *argv);
 157                 if (key == -1) /* no match found in keywords array, bail out. */
 158                         bb_error_msg_and_die(bb_msg_invalid_arg, *argv, applet_name);
 159                 argv++;
 160                 fd = xsocket(AF_INET, SOCK_STREAM, 0);
 161
 162 #if ENABLE_FEATURE_BRCTL_SHOW
 163                 if (key == ARG_show) { /* show */
 164                         char brname[IFNAMSIZ];
 165                         int bridx[MAX_PORTS];
 166                         int i, num;
 167                         arm_ioctl(args, BRCTL_GET_BRIDGES,
 168                                                 (unsigned long) bridx, MAX_PORTS);
 169                         num = xioctl(fd, SIOCGIFBR, args);
 170                         printf("bridge name\tbridge id\t\tSTP enabled\tinterfaces\n");
 171                         for (i = 0; i < num; i++) {
 172                                 char ifname[IFNAMSIZ];
 173                                 int j, tabs;
 174                                 struct __bridge_info bi;
 175                                 unsigned char *x;
 176
 177                                 if (!if_indextoname(bridx[i], brname))
 178                                         bb_perror_msg_and_die("can't get bridge name for index %d", i);
 179                                 strncpy_IFNAMSIZ(ifr.ifr_name, brname);
 180
 181                                 arm_ioctl(args, BRCTL_GET_BRIDGE_INFO,
 182                                                         (unsigned long) &bi, 0);
 183                                 xioctl(fd, SIOCDEVPRIVATE, &ifr);
 184                                 printf("%s\t\t", brname);
 185
 186                                 /* print bridge id */
 187                                 x = (unsigned char *) &bi.bridge_id;
 188                                 for (j = 0; j < 8; j++) {
 189                                         printf("%.2x", x[j]);
 190                                         if (j == 1)
 191                                                 bb_putchar('.');
 192                                 }
 193                                 printf(bi.stp_enabled ? "\tyes" : "\tno");
 194
 195                                 /* print interface list */
 196                                 arm_ioctl(args, BRCTL_GET_PORT_LIST,
 197                                                         (unsigned long) ifidx, MAX_PORTS);
 198                                 xioctl(fd, SIOCDEVPRIVATE, &ifr);
 199                                 tabs = 0;
 200                                 for (j = 0; j < MAX_PORTS; j++) {
 201                                         if (!ifidx[j])
 202                                                 continue;
 203                                         if (!if_indextoname(ifidx[j], ifname))
 204                                                 bb_perror_msg_and_die("can't get interface name for index %d", j);
 205                                         if (tabs)
 206                                                 printf("\t\t\t\t\t");
 207                                         else
 208                                                 tabs = 1;
 209                                         printf("\t\t%s\n", ifname);
 210                                 }
 211                                 if (!tabs)  /* bridge has no interfaces */
 212                                         bb_putchar('\n');
 213                         }
 214                         goto done;
 215                 }
 216 #endif
 217
 218                 if (!*argv) /* all but 'show' need at least one argument */
 219                         bb_show_usage();
 220
 221                 br = *argv++;
 222
 223                 if (key == ARG_addbr || key == ARG_delbr) { /* addbr or delbr */
 224                         ioctl_or_perror_and_die(fd,
 225                                         key == ARG_addbr ? SIOCBRADDBR : SIOCBRDELBR,
 226                                         br, "bridge %s", br);
 227                         goto done;
 228                 }
 229
 230                 if (!*argv) /* all but 'addbr/delbr' need at least two arguments */
 231                         bb_show_usage();
 232
 233                 strncpy_IFNAMSIZ(ifr.ifr_name, br);
 234                 if (key == ARG_addif || key == ARG_delif) { /* addif or delif */
 235                         brif = *argv;
 236                         ifr.ifr_ifindex = if_nametoindex(brif);
 237                         if (!ifr.ifr_ifindex) {
 238                                 bb_perror_msg_and_die("iface %s", brif);
 239                         }
 240                         ioctl_or_perror_and_die(fd,
 241                                         key == ARG_addif ? SIOCBRADDIF : SIOCBRDELIF,
 242                                         &ifr, "bridge %s", br);
 243                         goto done_next_argv;
 244                 }
 245 #if ENABLE_FEATURE_BRCTL_FANCY
 246                 if (key == ARG_stp) { /* stp */
 247                         static const char no_yes[] ALIGN1 =
 248                                 "0\0" "off\0" "n\0" "no\0"   /* 0 .. 3 */
 249                                 "1\0" "on\0"  "y\0" "yes\0"; /* 4 .. 7 */
 250                         int onoff = index_in_strings(no_yes, *argv);
 251                         if (onoff < 0)
 252                                 bb_error_msg_and_die(bb_msg_invalid_arg, *argv, applet_name);
 253                         onoff = (unsigned)onoff / 4;
 254                         arm_ioctl(args, BRCTL_SET_BRIDGE_STP_STATE, onoff, 0);
 255                         goto fire;
 256                 }
 257                 if ((unsigned)(key - ARG_setageing) < 4) { /* time related ops */
 258                         static const uint8_t ops[] ALIGN1 = {
 259                                 BRCTL_SET_AGEING_TIME,          /* ARG_setageing */
 260                                 BRCTL_SET_BRIDGE_FORWARD_DELAY, /* ARG_setfd     */
 261                                 BRCTL_SET_BRIDGE_HELLO_TIME,    /* ARG_sethello  */
 262                                 BRCTL_SET_BRIDGE_MAX_AGE        /* ARG_setmaxage */
 263                         };
 264                         arm_ioctl(args, ops[key - ARG_setageing], str_to_jiffies(*argv), 0);
 265                         goto fire;
 266                 }
 267                 if (key == ARG_setpathcost
 268                  || key == ARG_setportprio
 269                  || key == ARG_setbridgeprio
 270                 ) {
 271                         static const uint8_t ops[] ALIGN1 = {
 272                                 BRCTL_SET_PATH_COST,      /* ARG_setpathcost   */
 273                                 BRCTL_SET_PORT_PRIORITY,  /* ARG_setportprio   */
 274                                 BRCTL_SET_BRIDGE_PRIORITY /* ARG_setbridgeprio */
 275                         };
 276                         int port = -1;
 277                         unsigned arg1, arg2;
 278
 279                         if (key != ARG_setbridgeprio) {
 280                                 /* get portnum */
 281                                 unsigned i;
 282
 283                                 port = if_nametoindex(*argv++);
 284                                 if (!port)
 285                                         bb_error_msg_and_die(bb_msg_invalid_arg, *argv, "port");
 286                                 memset(ifidx, 0, sizeof ifidx);
 287                                 arm_ioctl(args, BRCTL_GET_PORT_LIST, (unsigned long)ifidx,
 288                                                 MAX_PORTS);
 289                                 xioctl(fd, SIOCDEVPRIVATE, &ifr);
 290                                 for (i = 0; i < MAX_PORTS; i++) {
 291                                         if (ifidx[i] == port) {
 292                                                 port = i;
 293                                                 break;
 294                                         }
 295                                 }
 296                         }
 297                         arg1 = port;
 298                         arg2 = xatoi_positive(*argv);
 299                         if (key == ARG_setbridgeprio) {
 300                                 arg1 = arg2;
 301                                 arg2 = 0;
 302                         }
 303                         arm_ioctl(args, ops[key - ARG_setpathcost], arg1, arg2);
 304                 }
 305  fire:
 306                 /* Execute the previously set command */
 307                 xioctl(fd, SIOCDEVPRIVATE, &ifr);
 308 #endif
 309  done_next_argv:
 310                 argv++;
 311  done:
 312                 close(fd);
 313         }
 314
 315         return EXIT_SUCCESS;
 316 }