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 openning 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
103 /* #include <net/if.h> - no. linux/if_bonding.h pulls in linux/if.h */
104 #include <linux/if.h>
105 //#include <net/if_arp.h> - not needed?
106 #include <linux/if_bonding.h>
107 #include <linux/sockios.h>
108 #include "fix_u32.h" /* hack, so we may include kernel's ethtool.h */
109 #include <linux/ethtool.h>
110 #ifndef BOND_ABI_VERSION
111 # define BOND_ABI_VERSION 2
119 struct ifreq mtu
, flags
, hwaddr
;
123 enum { skfd
= 3 }; /* AF_INET socket for ioctl() calls. */
125 unsigned abi_ver
; /* userland - kernel ABI version */
126 smallint hwaddr_set
; /* Master's hwaddr is set */
127 struct dev_data master
;
128 struct dev_data slave
;
130 #define G (*ptr_to_globals)
131 #define abi_ver (G.abi_ver )
132 #define hwaddr_set (G.hwaddr_set)
133 #define master (G.master )
134 #define slave (G.slave )
135 #define INIT_G() do { \
136 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
140 /* NOINLINEs are placed where it results in smaller code (gcc 4.3.1) */
142 static int ioctl_on_skfd(unsigned request
, struct ifreq
*ifr
)
144 return ioctl(skfd
, request
, ifr
);
147 static int set_ifrname_and_do_ioctl(unsigned request
, struct ifreq
*ifr
, const char *ifname
)
149 strncpy_IFNAMSIZ(ifr
->ifr_name
, ifname
);
150 return ioctl_on_skfd(request
, ifr
);
153 static int get_if_settings(char *ifname
, struct dev_data
*dd
)
157 res
= set_ifrname_and_do_ioctl(SIOCGIFMTU
, &dd
->mtu
, ifname
);
158 res
|= set_ifrname_and_do_ioctl(SIOCGIFFLAGS
, &dd
->flags
, ifname
);
159 res
|= set_ifrname_and_do_ioctl(SIOCGIFHWADDR
, &dd
->hwaddr
, ifname
);
164 static int get_slave_flags(char *slave_ifname
)
166 return set_ifrname_and_do_ioctl(SIOCGIFFLAGS
, &slave
.flags
, slave_ifname
);
169 static int set_hwaddr(char *ifname
, struct sockaddr
*hwaddr
)
173 memcpy(&(ifr
.ifr_hwaddr
), hwaddr
, sizeof(*hwaddr
));
174 return set_ifrname_and_do_ioctl(SIOCSIFHWADDR
, &ifr
, ifname
);
177 static int set_mtu(char *ifname
, int mtu
)
182 return set_ifrname_and_do_ioctl(SIOCSIFMTU
, &ifr
, ifname
);
185 static int set_if_flags(char *ifname
, int flags
)
189 ifr
.ifr_flags
= flags
;
190 return set_ifrname_and_do_ioctl(SIOCSIFFLAGS
, &ifr
, ifname
);
193 static int set_if_up(char *ifname
, int flags
)
195 int res
= set_if_flags(ifname
, flags
| IFF_UP
);
197 bb_perror_msg("%s: can't up", ifname
);
201 static int set_if_down(char *ifname
, int flags
)
203 int res
= set_if_flags(ifname
, flags
& ~IFF_UP
);
205 bb_perror_msg("%s: can't down", ifname
);
209 static int clear_if_addr(char *ifname
)
213 ifr
.ifr_addr
.sa_family
= AF_INET
;
214 memset(ifr
.ifr_addr
.sa_data
, 0, sizeof(ifr
.ifr_addr
.sa_data
));
215 return set_ifrname_and_do_ioctl(SIOCSIFADDR
, &ifr
, ifname
);
218 static int set_if_addr(char *master_ifname
, char *slave_ifname
)
220 #if (SIOCGIFADDR | SIOCSIFADDR \
221 | SIOCGIFDSTADDR | SIOCSIFDSTADDR \
222 | SIOCGIFBRDADDR | SIOCSIFBRDADDR \
223 | SIOCGIFNETMASK | SIOCSIFNETMASK) <= 0xffff
228 static const struct {
232 { SIOCGIFADDR
, SIOCSIFADDR
},
233 { SIOCGIFDSTADDR
, SIOCSIFDSTADDR
},
234 { SIOCGIFBRDADDR
, SIOCSIFBRDADDR
},
235 { SIOCGIFNETMASK
, SIOCSIFNETMASK
},
242 for (i
= 0; i
< ARRAY_SIZE(ifra
); i
++) {
243 res
= set_ifrname_and_do_ioctl(ifra
[i
].g_ioctl
, &ifr
, master_ifname
);
245 ifr
.ifr_addr
.sa_family
= AF_INET
;
246 memset(ifr
.ifr_addr
.sa_data
, 0,
247 sizeof(ifr
.ifr_addr
.sa_data
));
250 res
= set_ifrname_and_do_ioctl(ifra
[i
].s_ioctl
, &ifr
, slave_ifname
);
258 static void change_active(char *master_ifname
, char *slave_ifname
)
262 if (!(slave
.flags
.ifr_flags
& IFF_SLAVE
)) {
263 bb_error_msg_and_die("%s is not a slave", slave_ifname
);
266 strncpy_IFNAMSIZ(ifr
.ifr_slave
, slave_ifname
);
267 if (set_ifrname_and_do_ioctl(SIOCBONDCHANGEACTIVE
, &ifr
, master_ifname
)
268 && ioctl_on_skfd(BOND_CHANGE_ACTIVE_OLD
, &ifr
)
270 bb_perror_msg_and_die(
271 "master %s, slave %s: can't "
273 master_ifname
, slave_ifname
);
277 static NOINLINE
int enslave(char *master_ifname
, char *slave_ifname
)
282 if (slave
.flags
.ifr_flags
& IFF_SLAVE
) {
284 "%s is already a slave",
289 res
= set_if_down(slave_ifname
, slave
.flags
.ifr_flags
);
294 /* Older bonding versions would panic if the slave has no IP
295 * address, so get the IP setting from the master.
297 res
= set_if_addr(master_ifname
, slave_ifname
);
299 bb_perror_msg("%s: can't set address", slave_ifname
);
303 res
= clear_if_addr(slave_ifname
);
305 bb_perror_msg("%s: can't clear address", slave_ifname
);
310 if (master
.mtu
.ifr_mtu
!= slave
.mtu
.ifr_mtu
) {
311 res
= set_mtu(slave_ifname
, master
.mtu
.ifr_mtu
);
313 bb_perror_msg("%s: can't set MTU", slave_ifname
);
319 /* Master already has an hwaddr
320 * so set it's hwaddr to the slave
323 /* The driver is using an old ABI, so
324 * the application sets the slave's
327 if (set_hwaddr(slave_ifname
, &(master
.hwaddr
.ifr_hwaddr
))) {
328 bb_perror_msg("%s: can't set hw address",
333 /* For old ABI the application needs to bring the
336 if (set_if_up(slave_ifname
, slave
.flags
.ifr_flags
))
339 /* The driver is using a new ABI,
340 * so the driver takes care of setting
341 * the slave's hwaddr and bringing
345 /* No hwaddr for master yet, so
346 * set the slave's hwaddr to it
349 /* For old ABI, the master needs to be
350 * down before setting it's hwaddr
352 if (set_if_down(master_ifname
, master
.flags
.ifr_flags
))
356 if (set_hwaddr(master_ifname
, &(slave
.hwaddr
.ifr_hwaddr
))) {
357 bb_error_msg("%s: can't set hw address",
363 /* For old ABI, bring the master
366 if (set_if_up(master_ifname
, master
.flags
.ifr_flags
))
367 goto undo_master_mac
;
373 /* Do the real thing */
374 strncpy_IFNAMSIZ(ifr
.ifr_slave
, slave_ifname
);
375 if (set_ifrname_and_do_ioctl(SIOCBONDENSLAVE
, &ifr
, master_ifname
)
376 && ioctl_on_skfd(BOND_ENSLAVE_OLD
, &ifr
)
378 goto undo_master_mac
;
383 /* rollback (best effort) */
385 set_hwaddr(master_ifname
, &(master
.hwaddr
.ifr_hwaddr
));
390 set_hwaddr(slave_ifname
, &(slave
.hwaddr
.ifr_hwaddr
));
392 set_mtu(slave_ifname
, slave
.mtu
.ifr_mtu
);
396 static int release(char *master_ifname
, char *slave_ifname
)
401 if (!(slave
.flags
.ifr_flags
& IFF_SLAVE
)) {
402 bb_error_msg("%s is not a slave", slave_ifname
);
406 strncpy_IFNAMSIZ(ifr
.ifr_slave
, slave_ifname
);
407 if (set_ifrname_and_do_ioctl(SIOCBONDRELEASE
, &ifr
, master_ifname
) < 0
408 && ioctl_on_skfd(BOND_RELEASE_OLD
, &ifr
) < 0
413 /* The driver is using an old ABI, so we'll set the interface
414 * down to avoid any conflicts due to same MAC/IP
416 res
= set_if_down(slave_ifname
, slave
.flags
.ifr_flags
);
419 /* set to default mtu */
420 set_mtu(slave_ifname
, 1500);
425 static NOINLINE
void get_drv_info(char *master_ifname
)
428 struct ethtool_drvinfo info
;
430 memset(&ifr
, 0, sizeof(ifr
));
431 ifr
.ifr_data
= (caddr_t
)&info
;
432 info
.cmd
= ETHTOOL_GDRVINFO
;
433 /* both fields are 32 bytes long (long enough) */
434 strcpy(info
.driver
, "ifenslave");
435 strcpy(info
.fw_version
, utoa(BOND_ABI_VERSION
));
436 if (set_ifrname_and_do_ioctl(SIOCETHTOOL
, &ifr
, master_ifname
) < 0) {
437 if (errno
== EOPNOTSUPP
)
439 bb_perror_msg_and_die("%s: SIOCETHTOOL error", master_ifname
);
442 abi_ver
= bb_strtou(info
.fw_version
, NULL
, 0);
444 bb_error_msg_and_die("%s: SIOCETHTOOL error", master_ifname
);
447 int ifenslave_main(int argc
, char **argv
) MAIN_EXTERNALLY_VISIBLE
;
448 int ifenslave_main(int argc UNUSED_PARAM
, char **argv
)
450 char *master_ifname
, *slave_ifname
;
460 static const char ifenslave_longopts
[] ALIGN1
=
461 "change-active\0" No_argument
"c"
462 "detach\0" No_argument
"d"
463 "force\0" No_argument
"f"
464 /* "all-interfaces\0" No_argument "a" */
467 applet_long_options
= ifenslave_longopts
;
471 opt
= getopt32(argv
, "cdfa");
473 if (opt
& (opt
-1)) /* Only one option can be given */
476 master_ifname
= *argv
++;
478 /* No interface names - show all interfaces. */
479 if (!master_ifname
) {
480 display_interfaces(NULL
);
484 /* Open a basic socket */
485 xmove_fd(xsocket(AF_INET
, SOCK_DGRAM
, 0), skfd
);
487 /* Exchange abi version with bonding module */
488 get_drv_info(master_ifname
);
490 slave_ifname
= *argv
++;
492 if (opt
& (OPT_d
|OPT_c
)) {
493 /* --change or --detach, and no slaves given -
494 * show all interfaces. */
495 display_interfaces(slave_ifname
/* == NULL */);
496 return 2; /* why 2? */
498 /* A single arg means show the
499 * configuration for this interface
501 display_interfaces(master_ifname
);
505 if (get_if_settings(master_ifname
, &master
)) {
506 /* Probably a good reason not to go on */
507 bb_perror_msg_and_die("%s: can't get settings", master_ifname
);
510 /* Check if master is indeed a master;
511 * if not then fail any operation
513 if (!(master
.flags
.ifr_flags
& IFF_MASTER
))
514 bb_error_msg_and_die("%s is not a master", master_ifname
);
516 /* Check if master is up; if not then fail any operation */
517 if (!(master
.flags
.ifr_flags
& IFF_UP
))
518 bb_error_msg_and_die("%s is not up", master_ifname
);
521 /* Neither -c[hange] nor -d[etach] -> it's "enslave" then;
522 * and -f[orce] is not there too. Check that it's ethernet. */
523 if (!(opt
& (OPT_d
|OPT_c
|OPT_f
)) {
524 /* The family '1' is ARPHRD_ETHER for ethernet. */
525 if (master
.hwaddr
.ifr_hwaddr
.sa_family
!= 1) {
526 bb_error_msg_and_die(
527 "%s is not ethernet-like (-f overrides)",
533 /* Accepts only one slave */
535 /* Change active slave */
536 if (get_slave_flags(slave_ifname
)) {
537 bb_perror_msg_and_die(
538 "%s: can't get flags", slave_ifname
);
540 change_active(master_ifname
, slave_ifname
);
544 /* Accepts multiple slaves */
548 /* Detach a slave interface from the master */
549 rv
= get_slave_flags(slave_ifname
);
551 /* Can't work with this slave, */
552 /* remember the error and skip it */
554 "skipping %s: can't get flags",
559 rv
= release(master_ifname
, slave_ifname
);
561 bb_perror_msg("can't release %s from %s",
562 slave_ifname
, master_ifname
);
566 /* Attach a slave interface to the master */
567 rv
= get_if_settings(slave_ifname
, &slave
);
569 /* Can't work with this slave, */
570 /* remember the error and skip it */
572 "skipping %s: can't get settings",
577 rv
= enslave(master_ifname
, slave_ifname
);
579 bb_perror_msg("can't enslave %s to %s",
580 slave_ifname
, master_ifname
);
584 } while ((slave_ifname
= *argv
++) != NULL
);
586 if (ENABLE_FEATURE_CLEAN_UP
) {