3 * Mini ifenslave implementation for busybox
4 * Copyright (C) 2005 by Marc Leeman <marc.leeman@barco.com>
6 * ifenslave.c: Configure network interfaces for parallel routing.
8 * This program controls the Linux implementation of running multiple
9 * network interfaces in parallel.
11 * Author: Donald Becker <becker@cesdis.gsfc.nasa.gov>
12 * Copyright 1994-1996 Donald Becker
14 * This program is free software; you can redistribute it
15 * and/or modify it under the terms of the GNU General Public
16 * License as published by the Free Software Foundation.
18 * The author may be reached as becker@CESDIS.gsfc.nasa.gov, or C/O
19 * Center of Excellence in Space Data and Information Sciences
20 * Code 930.5, Goddard Space Flight Center, Greenbelt MD 20771
23 * - 2000/10/02 Willy Tarreau <willy at meta-x.org> :
24 * - few fixes. Master's MAC address is now correctly taken from
25 * the first device when not previously set ;
26 * - detach support : call BOND_RELEASE to detach an enslaved interface.
27 * - give a mini-howto from command-line help : # ifenslave -h
29 * - 2001/02/16 Chad N. Tindel <ctindel at ieee dot org> :
30 * - Master is now brought down before setting the MAC address. In
31 * the 2.4 kernel you can't change the MAC address while the device is
32 * up because you get EBUSY.
34 * - 2001/09/13 Takao Indoh <indou dot takao at jp dot fujitsu dot com>
35 * - Added the ability to change the active interface on a mode 1 bond
38 * - 2001/10/23 Chad N. Tindel <ctindel at ieee dot org> :
39 * - No longer set the MAC address of the master. The bond device will
40 * take care of this itself
41 * - Try the SIOC*** versions of the bonding ioctls before using the
43 * - 2002/02/18 Erik Habbinga <erik_habbinga @ hp dot com> :
44 * - ifr2.ifr_flags was not initialized in the hwaddr_notset case,
45 * SIOCGIFFLAGS now called before hwaddr_notset test
47 * - 2002/10/31 Tony Cureington <tony.cureington * hp_com> :
48 * - If the master does not have a hardware address when the first slave
49 * is enslaved, the master is assigned the hardware address of that
50 * slave - there is a comment in bonding.c stating "ifenslave takes
51 * care of this now." This corrects the problem of slaves having
52 * different hardware addresses in active-backup mode when
53 * multiple interfaces are specified on a single ifenslave command
54 * (ifenslave bond0 eth0 eth1).
56 * - 2003/03/18 - Tsippy Mendelson <tsippy.mendelson at intel dot com> and
57 * Shmulik Hen <shmulik.hen at intel dot com>
58 * - Moved setting the slave's mac address and opening it, from
59 * the application to the driver. This enables support of modes
60 * that need to use the unique mac address of each slave.
61 * The driver also takes care of closing the slave and restoring its
62 * original mac address upon release.
63 * In addition, block possibility of enslaving before the master is up.
64 * This prevents putting the system in an undefined state.
66 * - 2003/05/01 - Amir Noam <amir.noam at intel dot com>
67 * - Added ABI version control to restore compatibility between
68 * new/old ifenslave and new/old bonding.
69 * - Prevent adding an adapter that is already a slave.
70 * Fixes the problem of stalling the transmission and leaving
71 * the slave in a down state.
73 * - 2003/05/01 - Shmulik Hen <shmulik.hen at intel dot com>
74 * - Prevent enslaving if the bond device is down.
75 * Fixes the problem of leaving the system in unstable state and
76 * halting when trying to remove the module.
77 * - Close socket on all abnormal exists.
78 * - Add versioning scheme that follows that of the bonding driver.
79 * current version is 1.0.0 as a base line.
81 * - 2003/05/22 - Jay Vosburgh <fubar at us dot ibm dot com>
82 * - ifenslave -c was broken; it's now fixed
83 * - Fixed problem with routes vanishing from master during enslave
86 * - 2003/05/27 - Amir Noam <amir.noam at intel dot com>
87 * - Fix backward compatibility issues:
88 * For drivers not using ABI versions, slave was set down while
89 * it should be left up before enslaving.
90 * Also, master was not set down and the default set_mac_address()
91 * would fail and generate an error message in the system log.
92 * - For opt_c: slave should not be set to the master's setting
93 * while it is running. It was already set during enslave. To
94 * simplify things, it is now handeled separately.
96 * - 2003/12/01 - Shmulik Hen <shmulik.hen at intel dot com>
97 * - Code cleanup and style changes
98 * set version to 1.1.0
100 //config:config IFENSLAVE
101 //config: bool "ifenslave (13 kb)"
103 //config: select PLATFORM_LINUX
105 //config: Userspace application to bind several interfaces
106 //config: to a logical interface (use with kernel bonding driver).
108 //applet:IF_IFENSLAVE(APPLET_NOEXEC(ifenslave, ifenslave, BB_DIR_SBIN, BB_SUID_DROP, ifenslave))
110 //kbuild:lib-$(CONFIG_IFENSLAVE) += ifenslave.o interface.o
112 //usage:#define ifenslave_trivial_usage
113 //usage: "[-cdf] MASTER_IFACE SLAVE_IFACE..."
114 //usage:#define ifenslave_full_usage "\n\n"
115 //usage: "Configure network interfaces for parallel routing\n"
116 //usage: "\n -c Change active slave"
117 //usage: "\n -d Remove slave interface from bonding device"
118 //usage: "\n -f Force, even if interface is not Ethernet"
119 /* //usage: "\n -r Create a receive-only slave" */
121 //usage:#define ifenslave_example_usage
122 //usage: "To create a bond device, simply follow these three steps:\n"
123 //usage: "- ensure that the required drivers are properly loaded:\n"
124 //usage: " # modprobe bonding ; modprobe <3c59x|eepro100|pcnet32|tulip|...>\n"
125 //usage: "- assign an IP address to the bond device:\n"
126 //usage: " # ifconfig bond0 <addr> netmask <mask> broadcast <bcast>\n"
127 //usage: "- attach all the interfaces you need to the bond device:\n"
128 //usage: " # ifenslave bond0 eth0 eth1 eth2\n"
129 //usage: " If bond0 didn't have a MAC address, it will take eth0's. Then, all\n"
130 //usage: " interfaces attached AFTER this assignment will get the same MAC addr.\n\n"
131 //usage: " To detach a dead interface without setting the bond device down:\n"
132 //usage: " # ifenslave -d bond0 eth1\n\n"
133 //usage: " To set the bond device down and automatically release all the slaves:\n"
134 //usage: " # ifconfig bond0 down\n\n"
135 //usage: " To change active slave:\n"
136 //usage: " # ifenslave -c bond0 eth0\n"
140 /* #include <net/if.h> - no. linux/if_bonding.h pulls in linux/if.h */
141 #include <linux/if.h>
142 //#include <net/if_arp.h> - not needed?
143 #include <linux/if_bonding.h>
144 #include <linux/sockios.h>
145 #include "fix_u32.h" /* hack, so we may include kernel's ethtool.h */
146 #include <linux/ethtool.h>
147 #ifndef BOND_ABI_VERSION
148 # define BOND_ABI_VERSION 2
156 struct ifreq mtu, flags, hwaddr;
160 enum { skfd = 3 }; /* AF_INET socket for ioctl() calls. */
162 unsigned abi_ver; /* userland - kernel ABI version */
163 smallint hwaddr_set; /* Master's hwaddr is set */
164 struct dev_data master;
165 struct dev_data slave;
167 #define G (*ptr_to_globals)
168 #define abi_ver (G.abi_ver )
169 #define hwaddr_set (G.hwaddr_set)
170 #define master (G.master )
171 #define slave (G.slave )
172 #define INIT_G() do { \
173 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
177 /* NOINLINEs are placed where it results in smaller code (gcc 4.3.1) */
179 static int ioctl_on_skfd(unsigned request, struct ifreq *ifr)
181 return ioctl(skfd, request, ifr);
184 static int set_ifrname_and_do_ioctl(unsigned request, struct ifreq *ifr, const char *ifname)
186 strncpy_IFNAMSIZ(ifr->ifr_name, ifname);
187 return ioctl_on_skfd(request, ifr);
190 static int get_if_settings(char *ifname, struct dev_data *dd)
194 res = set_ifrname_and_do_ioctl(SIOCGIFMTU, &dd->mtu, ifname);
195 res |= set_ifrname_and_do_ioctl(SIOCGIFFLAGS, &dd->flags, ifname);
196 res |= set_ifrname_and_do_ioctl(SIOCGIFHWADDR, &dd->hwaddr, ifname);
201 static int get_slave_flags(char *slave_ifname)
203 return set_ifrname_and_do_ioctl(SIOCGIFFLAGS, &slave.flags, slave_ifname);
206 static int set_hwaddr(char *ifname, struct sockaddr *hwaddr)
210 memcpy(&(ifr.ifr_hwaddr), hwaddr, sizeof(*hwaddr));
211 return set_ifrname_and_do_ioctl(SIOCSIFHWADDR, &ifr, ifname);
214 static int set_mtu(char *ifname, int mtu)
219 return set_ifrname_and_do_ioctl(SIOCSIFMTU, &ifr, ifname);
222 static int set_if_flags(char *ifname, int flags)
226 ifr.ifr_flags = flags;
227 return set_ifrname_and_do_ioctl(SIOCSIFFLAGS, &ifr, ifname);
230 static int set_if_up(char *ifname, int flags)
232 int res = set_if_flags(ifname, flags | IFF_UP);
234 bb_perror_msg("%s: can't up", ifname);
238 static int set_if_down(char *ifname, int flags)
240 int res = set_if_flags(ifname, flags & ~IFF_UP);
242 bb_perror_msg("%s: can't down", ifname);
246 static int clear_if_addr(char *ifname)
250 ifr.ifr_addr.sa_family = AF_INET;
251 memset(ifr.ifr_addr.sa_data, 0, sizeof(ifr.ifr_addr.sa_data));
252 return set_ifrname_and_do_ioctl(SIOCSIFADDR, &ifr, ifname);
255 static int set_if_addr(char *master_ifname, char *slave_ifname)
257 #if (SIOCGIFADDR | SIOCSIFADDR \
258 | SIOCGIFDSTADDR | SIOCSIFDSTADDR \
259 | SIOCGIFBRDADDR | SIOCSIFBRDADDR \
260 | SIOCGIFNETMASK | SIOCSIFNETMASK) <= 0xffff
265 static const struct {
269 { SIOCGIFADDR, SIOCSIFADDR },
270 { SIOCGIFDSTADDR, SIOCSIFDSTADDR },
271 { SIOCGIFBRDADDR, SIOCSIFBRDADDR },
272 { SIOCGIFNETMASK, SIOCSIFNETMASK },
279 for (i = 0; i < ARRAY_SIZE(ifra); i++) {
280 res = set_ifrname_and_do_ioctl(ifra[i].g_ioctl, &ifr, master_ifname);
282 ifr.ifr_addr.sa_family = AF_INET;
283 memset(ifr.ifr_addr.sa_data, 0,
284 sizeof(ifr.ifr_addr.sa_data));
287 res = set_ifrname_and_do_ioctl(ifra[i].s_ioctl, &ifr, slave_ifname);
295 static void change_active(char *master_ifname, char *slave_ifname)
299 if (!(slave.flags.ifr_flags & IFF_SLAVE)) {
300 bb_error_msg_and_die("%s is not a slave", slave_ifname);
303 strncpy_IFNAMSIZ(ifr.ifr_slave, slave_ifname);
304 if (set_ifrname_and_do_ioctl(SIOCBONDCHANGEACTIVE, &ifr, master_ifname)
305 && ioctl_on_skfd(BOND_CHANGE_ACTIVE_OLD, &ifr)
307 bb_perror_msg_and_die(
308 "master %s, slave %s: can't "
310 master_ifname, slave_ifname);
314 static NOINLINE int enslave(char *master_ifname, char *slave_ifname)
319 if (slave.flags.ifr_flags & IFF_SLAVE) {
321 "%s is already a slave",
326 res = set_if_down(slave_ifname, slave.flags.ifr_flags);
331 /* Older bonding versions would panic if the slave has no IP
332 * address, so get the IP setting from the master.
334 res = set_if_addr(master_ifname, slave_ifname);
336 bb_perror_msg("%s: can't set address", slave_ifname);
340 res = clear_if_addr(slave_ifname);
342 bb_perror_msg("%s: can't clear address", slave_ifname);
347 if (master.mtu.ifr_mtu != slave.mtu.ifr_mtu) {
348 res = set_mtu(slave_ifname, master.mtu.ifr_mtu);
350 bb_perror_msg("%s: can't set MTU", slave_ifname);
356 /* Master already has an hwaddr
357 * so set it's hwaddr to the slave
360 /* The driver is using an old ABI, so
361 * the application sets the slave's
364 if (set_hwaddr(slave_ifname, &(master.hwaddr.ifr_hwaddr))) {
365 bb_perror_msg("%s: can't set hw address",
370 /* For old ABI the application needs to bring the
373 if (set_if_up(slave_ifname, slave.flags.ifr_flags))
376 /* The driver is using a new ABI,
377 * so the driver takes care of setting
378 * the slave's hwaddr and bringing
382 /* No hwaddr for master yet, so
383 * set the slave's hwaddr to it
386 /* For old ABI, the master needs to be
387 * down before setting it's hwaddr
389 if (set_if_down(master_ifname, master.flags.ifr_flags))
393 if (set_hwaddr(master_ifname, &(slave.hwaddr.ifr_hwaddr))) {
394 bb_error_msg("%s: can't set hw address",
400 /* For old ABI, bring the master
403 if (set_if_up(master_ifname, master.flags.ifr_flags))
404 goto undo_master_mac;
410 /* Do the real thing */
411 strncpy_IFNAMSIZ(ifr.ifr_slave, slave_ifname);
412 if (set_ifrname_and_do_ioctl(SIOCBONDENSLAVE, &ifr, master_ifname)
413 && ioctl_on_skfd(BOND_ENSLAVE_OLD, &ifr)
415 goto undo_master_mac;
420 /* rollback (best effort) */
422 set_hwaddr(master_ifname, &(master.hwaddr.ifr_hwaddr));
427 set_hwaddr(slave_ifname, &(slave.hwaddr.ifr_hwaddr));
429 set_mtu(slave_ifname, slave.mtu.ifr_mtu);
433 static int release(char *master_ifname, char *slave_ifname)
438 if (!(slave.flags.ifr_flags & IFF_SLAVE)) {
439 bb_error_msg("%s is not a slave", slave_ifname);
443 strncpy_IFNAMSIZ(ifr.ifr_slave, slave_ifname);
444 if (set_ifrname_and_do_ioctl(SIOCBONDRELEASE, &ifr, master_ifname) < 0
445 && ioctl_on_skfd(BOND_RELEASE_OLD, &ifr) < 0
450 /* The driver is using an old ABI, so we'll set the interface
451 * down to avoid any conflicts due to same MAC/IP
453 res = set_if_down(slave_ifname, slave.flags.ifr_flags);
456 /* set to default mtu */
457 set_mtu(slave_ifname, 1500);
462 static NOINLINE void get_drv_info(char *master_ifname)
465 struct ethtool_drvinfo info;
467 memset(&ifr, 0, sizeof(ifr));
468 ifr.ifr_data = (caddr_t)&info;
469 info.cmd = ETHTOOL_GDRVINFO;
470 /* both fields are 32 bytes long (long enough) */
471 strcpy(info.driver, "ifenslave");
472 strcpy(info.fw_version, utoa(BOND_ABI_VERSION));
473 if (set_ifrname_and_do_ioctl(SIOCETHTOOL, &ifr, master_ifname) < 0) {
474 if (errno == EOPNOTSUPP)
476 bb_perror_msg_and_die("%s: SIOCETHTOOL error", master_ifname);
479 abi_ver = bb_strtou(info.fw_version, NULL, 0);
481 bb_error_msg_and_die("%s: SIOCETHTOOL error", master_ifname);
484 int ifenslave_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
485 int ifenslave_main(int argc UNUSED_PARAM, char **argv)
487 char *master_ifname, *slave_ifname;
499 opt = getopt32long(argv, "cdfa",
500 "change-active\0" No_argument "c"
501 "detach\0" No_argument "d"
502 "force\0" No_argument "f"
503 /* "all-interfaces\0" No_argument "a" */
506 if (opt & (opt-1)) /* Only one option can be given */
509 master_ifname = *argv++;
511 /* No interface names - show all interfaces. */
512 if (!master_ifname) {
513 display_interfaces(NULL);
517 /* Open a basic socket */
518 xmove_fd(xsocket(AF_INET, SOCK_DGRAM, 0), skfd);
520 /* Exchange abi version with bonding module */
521 get_drv_info(master_ifname);
523 slave_ifname = *argv++;
525 if (opt & (OPT_d|OPT_c)) {
526 /* --change or --detach, and no slaves given -
527 * show all interfaces. */
528 display_interfaces(slave_ifname /* == NULL */);
529 return 2; /* why 2? */
531 /* A single arg means show the
532 * configuration for this interface
534 display_interfaces(master_ifname);
538 if (get_if_settings(master_ifname, &master)) {
539 /* Probably a good reason not to go on */
540 bb_perror_msg_and_die("%s: can't get settings", master_ifname);
543 /* Check if master is indeed a master;
544 * if not then fail any operation
546 if (!(master.flags.ifr_flags & IFF_MASTER))
547 bb_error_msg_and_die("%s is not a master", master_ifname);
549 /* Check if master is up; if not then fail any operation */
550 if (!(master.flags.ifr_flags & IFF_UP))
551 bb_error_msg_and_die("%s is not up", master_ifname);
554 /* Neither -c[hange] nor -d[etach] -> it's "enslave" then;
555 * and -f[orce] is not there too. Check that it's ethernet. */
556 if (!(opt & (OPT_d|OPT_c|OPT_f))) {
557 /* The family '1' is ARPHRD_ETHER for ethernet. */
558 if (master.hwaddr.ifr_hwaddr.sa_family != 1) {
559 bb_error_msg_and_die(
560 "%s is not ethernet-like (-f overrides)",
566 /* Accepts only one slave */
568 /* Change active slave */
569 if (get_slave_flags(slave_ifname)) {
570 bb_perror_msg_and_die(
571 "%s: can't get flags", slave_ifname);
573 change_active(master_ifname, slave_ifname);
577 /* Accepts multiple slaves */
581 /* Detach a slave interface from the master */
582 rv = get_slave_flags(slave_ifname);
584 /* Can't work with this slave, */
585 /* remember the error and skip it */
587 "skipping %s: can't get %s",
588 slave_ifname, "flags");
592 rv = release(master_ifname, slave_ifname);
594 bb_perror_msg("can't release %s from %s",
595 slave_ifname, master_ifname);
599 /* Attach a slave interface to the master */
600 rv = get_if_settings(slave_ifname, &slave);
602 /* Can't work with this slave, */
603 /* remember the error and skip it */
605 "skipping %s: can't get %s",
606 slave_ifname, "settings");
610 rv = enslave(master_ifname, slave_ifname);
612 bb_perror_msg("can't enslave %s to %s",
613 slave_ifname, master_ifname);
617 } while ((slave_ifname = *argv++) != NULL);
619 if (ENABLE_FEATURE_CLEAN_UP) {