/* vi: set sw=4 ts=4: */
/*
* Small implementation of brctl for busybox.
*
* Copyright (C) 2008 by Bernhard Reutner-Fischer
*
* Some helper functions from bridge-utils are
* Copyright (C) 2000 Lennert Buytenhek
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//config:config BRCTL
//config: bool "brctl (4.7 kb)"
//config: default y
//config: select PLATFORM_LINUX
//config: help
//config: Manage ethernet bridges.
//config: Supports addbr/delbr and addif/delif.
//config:
//config:config FEATURE_BRCTL_FANCY
//config: bool "Fancy options"
//config: default y
//config: depends on BRCTL
//config: help
//config: Add support for extended option like:
//config: setageing, setfd, sethello, setmaxage,
//config: setpathcost, setportprio, setbridgeprio,
//config: stp
//config: This adds about 600 bytes.
//config:
//config:config FEATURE_BRCTL_SHOW
//config: bool "Support show"
//config: default y
//config: depends on BRCTL && FEATURE_BRCTL_FANCY
//config: help
//config: Add support for option which prints the current config:
//config: show
//applet:IF_BRCTL(APPLET_NOEXEC(brctl, brctl, BB_DIR_USR_SBIN, BB_SUID_DROP, brctl))
//kbuild:lib-$(CONFIG_BRCTL) += brctl.o
//usage:#define brctl_trivial_usage
//usage: "COMMAND [BRIDGE [ARGS]]"
//usage:#define brctl_full_usage "\n\n"
//usage: "Manage ethernet bridges"
//usage: "\nCommands:"
//usage: IF_FEATURE_BRCTL_SHOW(
//usage: "\n show [BRIDGE]... Show bridges"
//usage: )
//usage: "\n addbr BRIDGE Create BRIDGE"
//usage: "\n delbr BRIDGE Delete BRIDGE"
//usage: "\n addif BRIDGE IFACE Add IFACE to BRIDGE"
//usage: "\n delif BRIDGE IFACE Delete IFACE from BRIDGE"
//usage: IF_FEATURE_BRCTL_FANCY(
//usage: "\n stp BRIDGE 1/yes/on|0/no/off STP on/off"
//usage: "\n setageing BRIDGE SECONDS Set ageing time"
//usage: "\n setfd BRIDGE SECONDS Set bridge forward delay"
//usage: "\n sethello BRIDGE SECONDS Set hello time"
//usage: "\n setmaxage BRIDGE SECONDS Set max message age"
//usage: "\n setbridgeprio BRIDGE PRIO Set bridge priority"
//usage: "\n setportprio BRIDGE IFACE PRIO Set port priority"
//usage: "\n setpathcost BRIDGE IFACE COST Set path cost"
//usage: )
// Not yet implemented:
// hairpin BRIDGE IFACE on|off Hairpin on/off
// showmacs BRIDGE List mac addrs
// showstp BRIDGE Show stp info
#include "libbb.h"
#include "common_bufsiz.h"
#include <linux/sockios.h>
#include <net/if.h>
#ifndef SIOCBRADDBR
# define SIOCBRADDBR BRCTL_ADD_BRIDGE
#endif
#ifndef SIOCBRDELBR
# define SIOCBRDELBR BRCTL_DEL_BRIDGE
#endif
#ifndef SIOCBRADDIF
# define SIOCBRADDIF BRCTL_ADD_IF
#endif
#ifndef SIOCBRDELIF
# define SIOCBRDELIF BRCTL_DEL_IF
#endif
#if ENABLE_FEATURE_BRCTL_FANCY
static unsigned str_to_jiffies(const char *time_str)
{
double dd;
char *endptr;
dd = /*bb_*/strtod(time_str, &endptr);
if (endptr == time_str || dd < 0)
bb_error_msg_and_die(bb_msg_invalid_arg_to, time_str, "timespec");
dd *= 100;
/* For purposes of brctl,
* capping SECONDS by ~20 million seconds is quite enough:
*/
if (dd > INT_MAX)
dd = INT_MAX;
return dd;
}
#endif
#define filedata bb_common_bufsiz1
static int read_file(const char *name)
{
int n = open_read_close(name, filedata, COMMON_BUFSIZE - 1);
if (n < 0) {
filedata[0] = '\0';
} else {
filedata[n] = '\0';
if (n != 0 && filedata[n - 1] == '\n')
filedata[--n] = '\0';
}
return n;
}
/* NB: we are in /sys/class/net
*/
static int show_bridge(const char *name, int need_hdr)
{
/* Output:
*bridge name bridge id STP enabled interfaces
*br0 8000.000000000000 no eth0
*/
char pathbuf[IFNAMSIZ + sizeof("/bridge/bridge_id") + 32];
int tabs;
DIR *ifaces;
struct dirent *ent;
char *sfx;
#if IFNAMSIZ == 16
sfx = pathbuf + sprintf(pathbuf, "%.16s/bridge/", name);
#else
sfx = pathbuf + sprintf(pathbuf, "%.*s/bridge/", (int)IFNAMSIZ, name);
#endif
strcpy(sfx, "bridge_id");
if (read_file(pathbuf) < 0)
return -1; /* this iface is not a bridge */
if (need_hdr)
puts("bridge name\tbridge id\t\tSTP enabled\tinterfaces");
printf("%s\t\t", name);
printf("%s\t", filedata);
strcpy(sfx, "stp_state");
read_file(pathbuf);
if (LONE_CHAR(filedata, '0'))
strcpy(filedata, "no");
else
if (LONE_CHAR(filedata, '1'))
strcpy(filedata, "yes");
fputs(filedata, stdout);
strcpy(sfx - (sizeof("bridge/")-1), "brif");
tabs = 0;
ifaces = opendir(pathbuf);
if (ifaces) {
while ((ent = readdir(ifaces)) != NULL) {
if (DOT_OR_DOTDOT(ent->d_name))
continue; /* . or .. */
if (tabs)
printf("\t\t\t\t\t");
else
tabs = 1;
printf("\t\t%s\n", ent->d_name);
}
closedir(ifaces);
}
if (!tabs) /* bridge has no interfaces */
bb_putchar('\n');
return 0;
}
static void write_uint(const char *name, const char *leaf, unsigned val)
{
char pathbuf[IFNAMSIZ + sizeof("/bridge/bridge_id") + 32];
int fd, n;
#if IFNAMSIZ == 16
sprintf(pathbuf, "%.16s/%s", name, leaf);
#else
sprintf(pathbuf, "%.*s/%s", (int)IFNAMSIZ, name, leaf);
#endif
fd = xopen(pathbuf, O_WRONLY);
n = sprintf(filedata, "%u\n", val);
if (write(fd, filedata, n) < 0)
bb_simple_perror_msg_and_die(name);
close(fd);
}
int brctl_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int brctl_main(int argc UNUSED_PARAM, char **argv)
{
static const char keywords[] ALIGN1 =
"addbr\0" "delbr\0" "addif\0" "delif\0"
IF_FEATURE_BRCTL_FANCY(
"stp\0"
"setageing\0" "setfd\0" "sethello\0" "setmaxage\0"
"setpathcost\0" "setportprio\0"
"setbridgeprio\0"
)
IF_FEATURE_BRCTL_SHOW("show\0");
enum { ARG_addbr = 0, ARG_delbr, ARG_addif, ARG_delif
IF_FEATURE_BRCTL_FANCY(,
ARG_stp,
ARG_setageing, ARG_setfd, ARG_sethello, ARG_setmaxage,
ARG_setpathcost, ARG_setportprio,
ARG_setbridgeprio
)
IF_FEATURE_BRCTL_SHOW(, ARG_show)
};
argv++;
if (!*argv) {
/* bare "brctl" shows --help */
bb_show_usage();
}
xchdir("/sys/class/net");
// while (*argv)
{
smallint key;
char *br;
key = index_in_strings(keywords, *argv);
if (key == -1) /* no match found in keywords array, bail out. */
bb_error_msg_and_die(bb_msg_invalid_arg_to, *argv, applet_name);
argv++;
#if ENABLE_FEATURE_BRCTL_SHOW
if (key == ARG_show) { /* show [BR]... */
DIR *net;
struct dirent *ent;
int need_hdr = 1;
int exitcode = EXIT_SUCCESS;
if (*argv) {
/* "show BR1 BR2 BR3" */
do {
if (show_bridge(*argv, need_hdr) >= 0) {
need_hdr = 0;
} else {
bb_error_msg("bridge %s does not exist", *argv);
//TODO: if device exists, but is not a BR, brctl from bridge-utils 1.6
//says this instead: "device eth0 is not a bridge"
exitcode = EXIT_FAILURE;
}
} while (*++argv != NULL);
return exitcode;
}
/* "show" (if no ifaces, shows nothing, not even header) */
net = xopendir(".");
while ((ent = readdir(net)) != NULL) {
if (DOT_OR_DOTDOT(ent->d_name))
continue; /* . or .. */
if (show_bridge(ent->d_name, need_hdr) >= 0)
need_hdr = 0;
}
if (ENABLE_FEATURE_CLEAN_UP)
closedir(net);
return exitcode;
}
#endif
if (!*argv) /* all but 'show' need at least one argument */
bb_show_usage();
br = *argv++;
if (key == ARG_addbr || key == ARG_delbr) {
/* addbr or delbr */
/* brctl from bridge-utils 1.6 still uses ioctl
* for SIOCBRADDBR / SIOCBRDELBR, not /sys accesses
*/
int fd = xsocket(AF_INET, SOCK_STREAM, 0);
ioctl_or_perror_and_die(fd,
key == ARG_addbr ? SIOCBRADDBR : SIOCBRDELBR,
br, "bridge %s", br
);
//close(fd);
//goto done;
/* bridge-utils 1.6 simply ignores trailing args:
* "brctl addbr BR1 ARGS" ignores ARGS
*/
if (ENABLE_FEATURE_CLEAN_UP)
close(fd);
return EXIT_SUCCESS;
}
if (!*argv) /* all but 'addbr/delbr' need at least two arguments */
bb_show_usage();
#if ENABLE_FEATURE_BRCTL_FANCY
if (key == ARG_stp) { /* stp */
static const char no_yes[] ALIGN1 =
"0\0" "off\0" "n\0" "no\0" /* 0 .. 3 */
"1\0" "on\0" "y\0" "yes\0"; /* 4 .. 7 */
int onoff = index_in_strings(no_yes, *argv);
if (onoff < 0)
bb_error_msg_and_die(bb_msg_invalid_arg_to, *argv, applet_name);
onoff = (unsigned)onoff / 4;
write_uint(br, "bridge/stp_state", onoff);
//goto done_next_argv;
return EXIT_SUCCESS;
}
if ((unsigned)(key - ARG_setageing) < 4) { /* time related ops */
/* setageing BR N: "N*100\n" to /sys/class/net/BR/bridge/ageing_time
* setfd BR N: "N*100\n" to /sys/class/net/BR/bridge/forward_delay
* sethello BR N: "N*100\n" to /sys/class/net/BR/bridge/hello_time
* setmaxage BR N: "N*100\n" to /sys/class/net/BR/bridge/max_age
*/
write_uint(br,
nth_string(
"bridge/ageing_time" "\0" /* ARG_setageing */
"bridge/forward_delay""\0" /* ARG_setfd */
"bridge/hello_time" "\0" /* ARG_sethello */
"bridge/max_age", /* ARG_setmaxage */
key - ARG_setageing
),
str_to_jiffies(*argv)
);
//goto done_next_argv;
return EXIT_SUCCESS;
}
if (key == ARG_setbridgeprio) {
write_uint(br, "bridge/priority", xatoi_positive(*argv));
//goto done_next_argv;
return EXIT_SUCCESS;
}
if (key == ARG_setpathcost
|| key == ARG_setportprio
) {
if (!argv[1])
bb_show_usage();
/* BR is not used (and ignored!) for these commands:
* "setpathcost BR PORT N" writes "N\n" to
* /sys/class/net/PORT/brport/path_cost
* "setportprio BR PORT N" writes "N\n" to
* /sys/class/net/PORT/brport/priority
*/
write_uint(argv[0],
nth_string(
"brport/path_cost" "\0" /* ARG_setpathcost */
"brport/priority", /* ARG_setportprio */
key - ARG_setpathcost
),
xatoi_positive(argv[1])
);
//argv++;
//goto done_next_argv;
return EXIT_SUCCESS;
}
/* TODO: "showmacs BR"
* port no\tmac addr\t\tis local?\tageing timer
* <sp><sp>1\txx:xx:xx:xx:xx:xx\tno\t\t<sp><sp><sp>1.31
* port no mac addr is local? ageing timer
* 1 xx:xx:xx:xx:xx:xx no 1.31
* Read fixed-sized records from /sys/class/net/BR/brforward:
* struct __fdb_entry {
* uint8_t mac_addr[ETH_ALEN];
* uint8_t port_no; //lsb
* uint8_t is_local;
* uint32_t ageing_timer_value;
* uint8_t port_hi;
* uint8_t pad0;
* uint16_t unused;
* };
*/
#endif
/* always true: if (key == ARG_addif || key == ARG_delif) */ {
/* addif or delif */
struct ifreq ifr;
int fd = xsocket(AF_INET, SOCK_STREAM, 0);
strncpy_IFNAMSIZ(ifr.ifr_name, br);
ifr.ifr_ifindex = if_nametoindex(*argv);
if (ifr.ifr_ifindex == 0) {
bb_perror_msg_and_die("iface %s", *argv);
}
ioctl_or_perror_and_die(fd,
key == ARG_addif ? SIOCBRADDIF : SIOCBRDELIF,
&ifr, "bridge %s", br
);
//close(fd);
//goto done_next_argv;
if (ENABLE_FEATURE_CLEAN_UP)
close(fd);
return EXIT_SUCCESS;
}
// done_next_argv:
// argv++;
// done:
}
return EXIT_SUCCESS;
}