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
101 //usage:#define ifenslave_trivial_usage
102 //usage: "[-cdf] MASTER_IFACE SLAVE_IFACE..."
103 //usage:#define ifenslave_full_usage "\n\n"
104 //usage: "Configure network interfaces for parallel routing\n"
105 //usage: "\n -c,--change-active Change active slave"
106 //usage: "\n -d,--detach Remove slave interface from bonding device"
107 //usage: "\n -f,--force Force, even if interface is not Ethernet"
108 /* //usage: "\n -r,--receive-slave Create a receive-only slave" */
110 //usage:#define ifenslave_example_usage
111 //usage: "To create a bond device, simply follow these three steps:\n"
112 //usage: "- ensure that the required drivers are properly loaded:\n"
113 //usage: " # modprobe bonding ; modprobe <3c59x|eepro100|pcnet32|tulip|...>\n"
114 //usage: "- assign an IP address to the bond device:\n"
115 //usage: " # ifconfig bond0 <addr> netmask <mask> broadcast <bcast>\n"
116 //usage: "- attach all the interfaces you need to the bond device:\n"
117 //usage: " # ifenslave bond0 eth0 eth1 eth2\n"
118 //usage: " If bond0 didn't have a MAC address, it will take eth0's. Then, all\n"
119 //usage: " interfaces attached AFTER this assignment will get the same MAC addr.\n\n"
120 //usage: " To detach a dead interface without setting the bond device down:\n"
121 //usage: " # ifenslave -d bond0 eth1\n\n"
122 //usage: " To set the bond device down and automatically release all the slaves:\n"
123 //usage: " # ifconfig bond0 down\n\n"
124 //usage: " To change active slave:\n"
125 //usage: " # ifenslave -c bond0 eth0\n"
129 /* #include <net/if.h> - no. linux/if_bonding.h pulls in linux/if.h */
130 #include <linux/if.h>
131 //#include <net/if_arp.h> - not needed?
132 #include <linux/if_bonding.h>
133 #include <linux/sockios.h>
134 #include "fix_u32.h" /* hack, so we may include kernel's ethtool.h */
135 #include <linux/ethtool.h>
136 #ifndef BOND_ABI_VERSION
137 # define BOND_ABI_VERSION 2
145 struct ifreq mtu
, flags
, hwaddr
;
149 enum { skfd
= 3 }; /* AF_INET socket for ioctl() calls. */
151 unsigned abi_ver
; /* userland - kernel ABI version */
152 smallint hwaddr_set
; /* Master's hwaddr is set */
153 struct dev_data master
;
154 struct dev_data slave
;
156 #define G (*ptr_to_globals)
157 #define abi_ver (G.abi_ver )
158 #define hwaddr_set (G.hwaddr_set)
159 #define master (G.master )
160 #define slave (G.slave )
161 #define INIT_G() do { \
162 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
166 /* NOINLINEs are placed where it results in smaller code (gcc 4.3.1) */
168 static int ioctl_on_skfd(unsigned request
, struct ifreq
*ifr
)
170 return ioctl(skfd
, request
, ifr
);
173 static int set_ifrname_and_do_ioctl(unsigned request
, struct ifreq
*ifr
, const char *ifname
)
175 strncpy_IFNAMSIZ(ifr
->ifr_name
, ifname
);
176 return ioctl_on_skfd(request
, ifr
);
179 static int get_if_settings(char *ifname
, struct dev_data
*dd
)
183 res
= set_ifrname_and_do_ioctl(SIOCGIFMTU
, &dd
->mtu
, ifname
);
184 res
|= set_ifrname_and_do_ioctl(SIOCGIFFLAGS
, &dd
->flags
, ifname
);
185 res
|= set_ifrname_and_do_ioctl(SIOCGIFHWADDR
, &dd
->hwaddr
, ifname
);
190 static int get_slave_flags(char *slave_ifname
)
192 return set_ifrname_and_do_ioctl(SIOCGIFFLAGS
, &slave
.flags
, slave_ifname
);
195 static int set_hwaddr(char *ifname
, struct sockaddr
*hwaddr
)
199 memcpy(&(ifr
.ifr_hwaddr
), hwaddr
, sizeof(*hwaddr
));
200 return set_ifrname_and_do_ioctl(SIOCSIFHWADDR
, &ifr
, ifname
);
203 static int set_mtu(char *ifname
, int mtu
)
208 return set_ifrname_and_do_ioctl(SIOCSIFMTU
, &ifr
, ifname
);
211 static int set_if_flags(char *ifname
, int flags
)
215 ifr
.ifr_flags
= flags
;
216 return set_ifrname_and_do_ioctl(SIOCSIFFLAGS
, &ifr
, ifname
);
219 static int set_if_up(char *ifname
, int flags
)
221 int res
= set_if_flags(ifname
, flags
| IFF_UP
);
223 bb_perror_msg("%s: can't up", ifname
);
227 static int set_if_down(char *ifname
, int flags
)
229 int res
= set_if_flags(ifname
, flags
& ~IFF_UP
);
231 bb_perror_msg("%s: can't down", ifname
);
235 static int clear_if_addr(char *ifname
)
239 ifr
.ifr_addr
.sa_family
= AF_INET
;
240 memset(ifr
.ifr_addr
.sa_data
, 0, sizeof(ifr
.ifr_addr
.sa_data
));
241 return set_ifrname_and_do_ioctl(SIOCSIFADDR
, &ifr
, ifname
);
244 static int set_if_addr(char *master_ifname
, char *slave_ifname
)
246 #if (SIOCGIFADDR | SIOCSIFADDR \
247 | SIOCGIFDSTADDR | SIOCSIFDSTADDR \
248 | SIOCGIFBRDADDR | SIOCSIFBRDADDR \
249 | SIOCGIFNETMASK | SIOCSIFNETMASK) <= 0xffff
254 static const struct {
258 { SIOCGIFADDR
, SIOCSIFADDR
},
259 { SIOCGIFDSTADDR
, SIOCSIFDSTADDR
},
260 { SIOCGIFBRDADDR
, SIOCSIFBRDADDR
},
261 { SIOCGIFNETMASK
, SIOCSIFNETMASK
},
268 for (i
= 0; i
< ARRAY_SIZE(ifra
); i
++) {
269 res
= set_ifrname_and_do_ioctl(ifra
[i
].g_ioctl
, &ifr
, master_ifname
);
271 ifr
.ifr_addr
.sa_family
= AF_INET
;
272 memset(ifr
.ifr_addr
.sa_data
, 0,
273 sizeof(ifr
.ifr_addr
.sa_data
));
276 res
= set_ifrname_and_do_ioctl(ifra
[i
].s_ioctl
, &ifr
, slave_ifname
);
284 static void change_active(char *master_ifname
, char *slave_ifname
)
288 if (!(slave
.flags
.ifr_flags
& IFF_SLAVE
)) {
289 bb_error_msg_and_die("%s is not a slave", slave_ifname
);
292 strncpy_IFNAMSIZ(ifr
.ifr_slave
, slave_ifname
);
293 if (set_ifrname_and_do_ioctl(SIOCBONDCHANGEACTIVE
, &ifr
, master_ifname
)
294 && ioctl_on_skfd(BOND_CHANGE_ACTIVE_OLD
, &ifr
)
296 bb_perror_msg_and_die(
297 "master %s, slave %s: can't "
299 master_ifname
, slave_ifname
);
303 static NOINLINE
int enslave(char *master_ifname
, char *slave_ifname
)
308 if (slave
.flags
.ifr_flags
& IFF_SLAVE
) {
310 "%s is already a slave",
315 res
= set_if_down(slave_ifname
, slave
.flags
.ifr_flags
);
320 /* Older bonding versions would panic if the slave has no IP
321 * address, so get the IP setting from the master.
323 res
= set_if_addr(master_ifname
, slave_ifname
);
325 bb_perror_msg("%s: can't set address", slave_ifname
);
329 res
= clear_if_addr(slave_ifname
);
331 bb_perror_msg("%s: can't clear address", slave_ifname
);
336 if (master
.mtu
.ifr_mtu
!= slave
.mtu
.ifr_mtu
) {
337 res
= set_mtu(slave_ifname
, master
.mtu
.ifr_mtu
);
339 bb_perror_msg("%s: can't set MTU", slave_ifname
);
345 /* Master already has an hwaddr
346 * so set it's hwaddr to the slave
349 /* The driver is using an old ABI, so
350 * the application sets the slave's
353 if (set_hwaddr(slave_ifname
, &(master
.hwaddr
.ifr_hwaddr
))) {
354 bb_perror_msg("%s: can't set hw address",
359 /* For old ABI the application needs to bring the
362 if (set_if_up(slave_ifname
, slave
.flags
.ifr_flags
))
365 /* The driver is using a new ABI,
366 * so the driver takes care of setting
367 * the slave's hwaddr and bringing
371 /* No hwaddr for master yet, so
372 * set the slave's hwaddr to it
375 /* For old ABI, the master needs to be
376 * down before setting it's hwaddr
378 if (set_if_down(master_ifname
, master
.flags
.ifr_flags
))
382 if (set_hwaddr(master_ifname
, &(slave
.hwaddr
.ifr_hwaddr
))) {
383 bb_error_msg("%s: can't set hw address",
389 /* For old ABI, bring the master
392 if (set_if_up(master_ifname
, master
.flags
.ifr_flags
))
393 goto undo_master_mac
;
399 /* Do the real thing */
400 strncpy_IFNAMSIZ(ifr
.ifr_slave
, slave_ifname
);
401 if (set_ifrname_and_do_ioctl(SIOCBONDENSLAVE
, &ifr
, master_ifname
)
402 && ioctl_on_skfd(BOND_ENSLAVE_OLD
, &ifr
)
404 goto undo_master_mac
;
409 /* rollback (best effort) */
411 set_hwaddr(master_ifname
, &(master
.hwaddr
.ifr_hwaddr
));
416 set_hwaddr(slave_ifname
, &(slave
.hwaddr
.ifr_hwaddr
));
418 set_mtu(slave_ifname
, slave
.mtu
.ifr_mtu
);
422 static int release(char *master_ifname
, char *slave_ifname
)
427 if (!(slave
.flags
.ifr_flags
& IFF_SLAVE
)) {
428 bb_error_msg("%s is not a slave", slave_ifname
);
432 strncpy_IFNAMSIZ(ifr
.ifr_slave
, slave_ifname
);
433 if (set_ifrname_and_do_ioctl(SIOCBONDRELEASE
, &ifr
, master_ifname
) < 0
434 && ioctl_on_skfd(BOND_RELEASE_OLD
, &ifr
) < 0
439 /* The driver is using an old ABI, so we'll set the interface
440 * down to avoid any conflicts due to same MAC/IP
442 res
= set_if_down(slave_ifname
, slave
.flags
.ifr_flags
);
445 /* set to default mtu */
446 set_mtu(slave_ifname
, 1500);
451 static NOINLINE
void get_drv_info(char *master_ifname
)
454 struct ethtool_drvinfo info
;
456 memset(&ifr
, 0, sizeof(ifr
));
457 ifr
.ifr_data
= (caddr_t
)&info
;
458 info
.cmd
= ETHTOOL_GDRVINFO
;
459 /* both fields are 32 bytes long (long enough) */
460 strcpy(info
.driver
, "ifenslave");
461 strcpy(info
.fw_version
, utoa(BOND_ABI_VERSION
));
462 if (set_ifrname_and_do_ioctl(SIOCETHTOOL
, &ifr
, master_ifname
) < 0) {
463 if (errno
== EOPNOTSUPP
)
465 bb_perror_msg_and_die("%s: SIOCETHTOOL error", master_ifname
);
468 abi_ver
= bb_strtou(info
.fw_version
, NULL
, 0);
470 bb_error_msg_and_die("%s: SIOCETHTOOL error", master_ifname
);
473 int ifenslave_main(int argc
, char **argv
) MAIN_EXTERNALLY_VISIBLE
;
474 int ifenslave_main(int argc UNUSED_PARAM
, char **argv
)
476 char *master_ifname
, *slave_ifname
;
486 static const char ifenslave_longopts
[] ALIGN1
=
487 "change-active\0" No_argument
"c"
488 "detach\0" No_argument
"d"
489 "force\0" No_argument
"f"
490 /* "all-interfaces\0" No_argument "a" */
493 applet_long_options
= ifenslave_longopts
;
497 opt
= getopt32(argv
, "cdfa");
499 if (opt
& (opt
-1)) /* Only one option can be given */
502 master_ifname
= *argv
++;
504 /* No interface names - show all interfaces. */
505 if (!master_ifname
) {
506 display_interfaces(NULL
);
510 /* Open a basic socket */
511 xmove_fd(xsocket(AF_INET
, SOCK_DGRAM
, 0), skfd
);
513 /* Exchange abi version with bonding module */
514 get_drv_info(master_ifname
);
516 slave_ifname
= *argv
++;
518 if (opt
& (OPT_d
|OPT_c
)) {
519 /* --change or --detach, and no slaves given -
520 * show all interfaces. */
521 display_interfaces(slave_ifname
/* == NULL */);
522 return 2; /* why 2? */
524 /* A single arg means show the
525 * configuration for this interface
527 display_interfaces(master_ifname
);
531 if (get_if_settings(master_ifname
, &master
)) {
532 /* Probably a good reason not to go on */
533 bb_perror_msg_and_die("%s: can't get settings", master_ifname
);
536 /* Check if master is indeed a master;
537 * if not then fail any operation
539 if (!(master
.flags
.ifr_flags
& IFF_MASTER
))
540 bb_error_msg_and_die("%s is not a master", master_ifname
);
542 /* Check if master is up; if not then fail any operation */
543 if (!(master
.flags
.ifr_flags
& IFF_UP
))
544 bb_error_msg_and_die("%s is not up", master_ifname
);
547 /* Neither -c[hange] nor -d[etach] -> it's "enslave" then;
548 * and -f[orce] is not there too. Check that it's ethernet. */
549 if (!(opt
& (OPT_d
|OPT_c
|OPT_f
))) {
550 /* The family '1' is ARPHRD_ETHER for ethernet. */
551 if (master
.hwaddr
.ifr_hwaddr
.sa_family
!= 1) {
552 bb_error_msg_and_die(
553 "%s is not ethernet-like (-f overrides)",
559 /* Accepts only one slave */
561 /* Change active slave */
562 if (get_slave_flags(slave_ifname
)) {
563 bb_perror_msg_and_die(
564 "%s: can't get flags", slave_ifname
);
566 change_active(master_ifname
, slave_ifname
);
570 /* Accepts multiple slaves */
574 /* Detach a slave interface from the master */
575 rv
= get_slave_flags(slave_ifname
);
577 /* Can't work with this slave, */
578 /* remember the error and skip it */
580 "skipping %s: can't get flags",
585 rv
= release(master_ifname
, slave_ifname
);
587 bb_perror_msg("can't release %s from %s",
588 slave_ifname
, master_ifname
);
592 /* Attach a slave interface to the master */
593 rv
= get_if_settings(slave_ifname
, &slave
);
595 /* Can't work with this slave, */
596 /* remember the error and skip it */
598 "skipping %s: can't get settings",
603 rv
= enslave(master_ifname
, slave_ifname
);
605 bb_perror_msg("can't enslave %s to %s",
606 slave_ifname
, master_ifname
);
610 } while ((slave_ifname
= *argv
++) != NULL
);
612 if (ENABLE_FEATURE_CLEAN_UP
) {