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 <net/if_arp.h>
105 #include <linux/if_bonding.h>
106 #include <linux/sockios.h>
112 typedef uint64_t u64
; /* hack, so we may include kernel's ethtool.h */
113 typedef uint32_t u32
; /* ditto */
114 typedef uint16_t u16
; /* ditto */
115 typedef uint8_t u8
; /* ditto */
116 #include <linux/ethtool.h>
120 struct ifreq mtu
, flags
, hwaddr
;
124 enum { skfd
= 3 }; /* AF_INET socket for ioctl() calls. */
126 unsigned abi_ver
; /* userland - kernel ABI version */
127 smallint hwaddr_set
; /* Master's hwaddr is set */
128 struct dev_data master
;
129 struct dev_data slave
;
131 #define G (*ptr_to_globals)
132 #define abi_ver (G.abi_ver )
133 #define hwaddr_set (G.hwaddr_set)
134 #define master (G.master )
135 #define slave (G.slave )
136 #define INIT_G() do { \
137 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
141 /* NOINLINEs are placed where it results in smaller code (gcc 4.3.1) */
143 static int ioctl_on_skfd(unsigned request
, struct ifreq
*ifr
)
145 return ioctl(skfd
, request
, ifr
);
148 static int set_ifrname_and_do_ioctl(unsigned request
, struct ifreq
*ifr
, const char *ifname
)
150 strncpy_IFNAMSIZ(ifr
->ifr_name
, ifname
);
151 return ioctl_on_skfd(request
, ifr
);
154 static int get_if_settings(char *ifname
, struct dev_data
*dd
)
158 res
= set_ifrname_and_do_ioctl(SIOCGIFMTU
, &dd
->mtu
, ifname
);
159 res
|= set_ifrname_and_do_ioctl(SIOCGIFFLAGS
, &dd
->flags
, ifname
);
160 res
|= set_ifrname_and_do_ioctl(SIOCGIFHWADDR
, &dd
->hwaddr
, ifname
);
165 static int get_slave_flags(char *slave_ifname
)
167 return set_ifrname_and_do_ioctl(SIOCGIFFLAGS
, &slave
.flags
, slave_ifname
);
170 static int set_hwaddr(char *ifname
, struct sockaddr
*hwaddr
)
174 memcpy(&(ifr
.ifr_hwaddr
), hwaddr
, sizeof(*hwaddr
));
175 return set_ifrname_and_do_ioctl(SIOCSIFHWADDR
, &ifr
, ifname
);
178 static int set_mtu(char *ifname
, int mtu
)
183 return set_ifrname_and_do_ioctl(SIOCSIFMTU
, &ifr
, ifname
);
186 static int set_if_flags(char *ifname
, int flags
)
190 ifr
.ifr_flags
= flags
;
191 return set_ifrname_and_do_ioctl(SIOCSIFFLAGS
, &ifr
, ifname
);
194 static int set_if_up(char *ifname
, int flags
)
196 int res
= set_if_flags(ifname
, flags
| IFF_UP
);
198 bb_perror_msg("%s: can't up", ifname
);
202 static int set_if_down(char *ifname
, int flags
)
204 int res
= set_if_flags(ifname
, flags
& ~IFF_UP
);
206 bb_perror_msg("%s: can't down", ifname
);
210 static int clear_if_addr(char *ifname
)
214 ifr
.ifr_addr
.sa_family
= AF_INET
;
215 memset(ifr
.ifr_addr
.sa_data
, 0, sizeof(ifr
.ifr_addr
.sa_data
));
216 return set_ifrname_and_do_ioctl(SIOCSIFADDR
, &ifr
, ifname
);
219 static int set_if_addr(char *master_ifname
, char *slave_ifname
)
221 #if (SIOCGIFADDR | SIOCSIFADDR \
222 | SIOCGIFDSTADDR | SIOCSIFDSTADDR \
223 | SIOCGIFBRDADDR | SIOCSIFBRDADDR \
224 | SIOCGIFNETMASK | SIOCSIFNETMASK) <= 0xffff
229 static const struct {
233 { SIOCGIFADDR
, SIOCSIFADDR
},
234 { SIOCGIFDSTADDR
, SIOCSIFDSTADDR
},
235 { SIOCGIFBRDADDR
, SIOCSIFBRDADDR
},
236 { SIOCGIFNETMASK
, SIOCSIFNETMASK
},
243 for (i
= 0; i
< ARRAY_SIZE(ifra
); i
++) {
244 res
= set_ifrname_and_do_ioctl(ifra
[i
].g_ioctl
, &ifr
, master_ifname
);
246 ifr
.ifr_addr
.sa_family
= AF_INET
;
247 memset(ifr
.ifr_addr
.sa_data
, 0,
248 sizeof(ifr
.ifr_addr
.sa_data
));
251 res
= set_ifrname_and_do_ioctl(ifra
[i
].s_ioctl
, &ifr
, slave_ifname
);
259 static void change_active(char *master_ifname
, char *slave_ifname
)
263 if (!(slave
.flags
.ifr_flags
& IFF_SLAVE
)) {
264 bb_error_msg_and_die("%s is not a slave", slave_ifname
);
267 strncpy_IFNAMSIZ(ifr
.ifr_slave
, slave_ifname
);
268 if (set_ifrname_and_do_ioctl(SIOCBONDCHANGEACTIVE
, &ifr
, master_ifname
)
269 && ioctl_on_skfd(BOND_CHANGE_ACTIVE_OLD
, &ifr
)
271 bb_perror_msg_and_die(
272 "master %s, slave %s: can't "
274 master_ifname
, slave_ifname
);
278 static NOINLINE
int enslave(char *master_ifname
, char *slave_ifname
)
283 if (slave
.flags
.ifr_flags
& IFF_SLAVE
) {
285 "%s is already a slave",
290 res
= set_if_down(slave_ifname
, slave
.flags
.ifr_flags
);
295 /* Older bonding versions would panic if the slave has no IP
296 * address, so get the IP setting from the master.
298 res
= set_if_addr(master_ifname
, slave_ifname
);
300 bb_perror_msg("%s: can't set address", slave_ifname
);
304 res
= clear_if_addr(slave_ifname
);
306 bb_perror_msg("%s: can't clear address", slave_ifname
);
311 if (master
.mtu
.ifr_mtu
!= slave
.mtu
.ifr_mtu
) {
312 res
= set_mtu(slave_ifname
, master
.mtu
.ifr_mtu
);
314 bb_perror_msg("%s: can't set MTU", slave_ifname
);
320 /* Master already has an hwaddr
321 * so set it's hwaddr to the slave
324 /* The driver is using an old ABI, so
325 * the application sets the slave's
328 if (set_hwaddr(slave_ifname
, &(master
.hwaddr
.ifr_hwaddr
))) {
329 bb_perror_msg("%s: can't set hw address",
334 /* For old ABI the application needs to bring the
337 if (set_if_up(slave_ifname
, slave
.flags
.ifr_flags
))
340 /* The driver is using a new ABI,
341 * so the driver takes care of setting
342 * the slave's hwaddr and bringing
346 /* No hwaddr for master yet, so
347 * set the slave's hwaddr to it
350 /* For old ABI, the master needs to be
351 * down before setting it's hwaddr
353 if (set_if_down(master_ifname
, master
.flags
.ifr_flags
))
357 if (set_hwaddr(master_ifname
, &(slave
.hwaddr
.ifr_hwaddr
))) {
358 bb_error_msg("%s: can't set hw address",
364 /* For old ABI, bring the master
367 if (set_if_up(master_ifname
, master
.flags
.ifr_flags
))
368 goto undo_master_mac
;
374 /* Do the real thing */
375 strncpy_IFNAMSIZ(ifr
.ifr_slave
, slave_ifname
);
376 if (set_ifrname_and_do_ioctl(SIOCBONDENSLAVE
, &ifr
, master_ifname
)
377 && ioctl_on_skfd(BOND_ENSLAVE_OLD
, &ifr
)
379 goto undo_master_mac
;
384 /* rollback (best effort) */
386 set_hwaddr(master_ifname
, &(master
.hwaddr
.ifr_hwaddr
));
391 set_hwaddr(slave_ifname
, &(slave
.hwaddr
.ifr_hwaddr
));
393 set_mtu(slave_ifname
, slave
.mtu
.ifr_mtu
);
397 static int release(char *master_ifname
, char *slave_ifname
)
402 if (!(slave
.flags
.ifr_flags
& IFF_SLAVE
)) {
403 bb_error_msg("%s is not a slave", slave_ifname
);
407 strncpy_IFNAMSIZ(ifr
.ifr_slave
, slave_ifname
);
408 if (set_ifrname_and_do_ioctl(SIOCBONDRELEASE
, &ifr
, master_ifname
) < 0
409 && ioctl_on_skfd(BOND_RELEASE_OLD
, &ifr
) < 0
414 /* The driver is using an old ABI, so we'll set the interface
415 * down to avoid any conflicts due to same MAC/IP
417 res
= set_if_down(slave_ifname
, slave
.flags
.ifr_flags
);
420 /* set to default mtu */
421 set_mtu(slave_ifname
, 1500);
426 static NOINLINE
void get_drv_info(char *master_ifname
)
429 struct ethtool_drvinfo info
;
431 memset(&ifr
, 0, sizeof(ifr
));
432 ifr
.ifr_data
= (caddr_t
)&info
;
433 info
.cmd
= ETHTOOL_GDRVINFO
;
434 /* both fields are 32 bytes long (long enough) */
435 strcpy(info
.driver
, "ifenslave");
436 strcpy(info
.fw_version
, utoa(BOND_ABI_VERSION
));
437 if (set_ifrname_and_do_ioctl(SIOCETHTOOL
, &ifr
, master_ifname
) < 0) {
438 if (errno
== EOPNOTSUPP
)
440 bb_perror_msg_and_die("%s: SIOCETHTOOL error", master_ifname
);
443 abi_ver
= bb_strtou(info
.fw_version
, NULL
, 0);
445 bb_error_msg_and_die("%s: SIOCETHTOOL error", master_ifname
);
448 int ifenslave_main(int argc
, char **argv
) MAIN_EXTERNALLY_VISIBLE
;
449 int ifenslave_main(int argc UNUSED_PARAM
, char **argv
)
451 char *master_ifname
, *slave_ifname
;
460 #if ENABLE_GETOPT_LONG
461 static const char ifenslave_longopts
[] ALIGN1
=
462 "change-active\0" No_argument
"c"
463 "detach\0" No_argument
"d"
464 "force\0" No_argument
"f"
465 /* "all-interfaces\0" No_argument "a" */
468 applet_long_options
= ifenslave_longopts
;
472 opt
= getopt32(argv
, "cdfa");
474 if (opt
& (opt
-1)) /* Only one option can be given */
477 master_ifname
= *argv
++;
479 /* No interface names - show all interfaces. */
480 if (!master_ifname
) {
481 display_interfaces(NULL
);
485 /* Open a basic socket */
486 xmove_fd(xsocket(AF_INET
, SOCK_DGRAM
, 0), skfd
);
488 /* Exchange abi version with bonding module */
489 get_drv_info(master_ifname
);
491 slave_ifname
= *argv
++;
493 if (opt
& (OPT_d
|OPT_c
)) {
494 /* --change or --detach, and no slaves given -
495 * show all interfaces. */
496 display_interfaces(slave_ifname
/* == NULL */);
497 return 2; /* why 2? */
499 /* A single arg means show the
500 * configuration for this interface
502 display_interfaces(master_ifname
);
506 if (get_if_settings(master_ifname
, &master
)) {
507 /* Probably a good reason not to go on */
508 bb_perror_msg_and_die("%s: can't get settings", master_ifname
);
511 /* Check if master is indeed a master;
512 * if not then fail any operation
514 if (!(master
.flags
.ifr_flags
& IFF_MASTER
))
515 bb_error_msg_and_die("%s is not a master", master_ifname
);
517 /* Check if master is up; if not then fail any operation */
518 if (!(master
.flags
.ifr_flags
& IFF_UP
))
519 bb_error_msg_and_die("%s is not up", master_ifname
);
522 /* Neither -c[hange] nor -d[etach] -> it's "enslave" then;
523 * and -f[orce] is not there too. Check that it's ethernet. */
524 if (!(opt
& (OPT_d
|OPT_c
|OPT_f
)) {
525 /* The family '1' is ARPHRD_ETHER for ethernet. */
526 if (master
.hwaddr
.ifr_hwaddr
.sa_family
!= 1) {
527 bb_error_msg_and_die(
528 "%s is not ethernet-like (-f overrides)",
534 /* Accepts only one slave */
536 /* Change active slave */
537 if (get_slave_flags(slave_ifname
)) {
538 bb_perror_msg_and_die(
539 "%s: can't get flags", slave_ifname
);
541 change_active(master_ifname
, slave_ifname
);
545 /* Accepts multiple slaves */
549 /* Detach a slave interface from the master */
550 rv
= get_slave_flags(slave_ifname
);
552 /* Can't work with this slave, */
553 /* remember the error and skip it */
555 "skipping %s: can't get flags",
560 rv
= release(master_ifname
, slave_ifname
);
562 bb_perror_msg("can't release %s from %s",
563 slave_ifname
, master_ifname
);
567 /* Attach a slave interface to the master */
568 rv
= get_if_settings(slave_ifname
, &slave
);
570 /* Can't work with this slave, */
571 /* remember the error and skip it */
573 "skipping %s: can't get settings",
578 rv
= enslave(master_ifname
, slave_ifname
);
580 bb_perror_msg("can't enslave %s to %s",
581 slave_ifname
, master_ifname
);
585 } while ((slave_ifname
= *argv
++) != NULL
);
587 if (ENABLE_FEATURE_CLEAN_UP
) {