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: "\nOptions:"
106 //usage: "\n -c,--change-active Change active slave"
107 //usage: "\n -d,--detach Remove slave interface from bonding device"
108 //usage: "\n -f,--force Force, even if interface is not Ethernet"
109 /* //usage: "\n -r,--receive-slave Create a receive-only slave" */
111 //usage:#define ifenslave_example_usage
112 //usage: "To create a bond device, simply follow these three steps:\n"
113 //usage: "- ensure that the required drivers are properly loaded:\n"
114 //usage: " # modprobe bonding ; modprobe <3c59x|eepro100|pcnet32|tulip|...>\n"
115 //usage: "- assign an IP address to the bond device:\n"
116 //usage: " # ifconfig bond0 <addr> netmask <mask> broadcast <bcast>\n"
117 //usage: "- attach all the interfaces you need to the bond device:\n"
118 //usage: " # ifenslave bond0 eth0 eth1 eth2\n"
119 //usage: " If bond0 didn't have a MAC address, it will take eth0's. Then, all\n"
120 //usage: " interfaces attached AFTER this assignment will get the same MAC addr.\n\n"
121 //usage: " To detach a dead interface without setting the bond device down:\n"
122 //usage: " # ifenslave -d bond0 eth1\n\n"
123 //usage: " To set the bond device down and automatically release all the slaves:\n"
124 //usage: " # ifconfig bond0 down\n\n"
125 //usage: " To change active slave:\n"
126 //usage: " # ifenslave -c bond0 eth0\n"
130 /* #include <net/if.h> - no. linux/if_bonding.h pulls in linux/if.h */
131 #include <linux/if.h>
132 //#include <net/if_arp.h> - not needed?
133 #include <linux/if_bonding.h>
134 #include <linux/sockios.h>
135 #include "fix_u32.h" /* hack, so we may include kernel's ethtool.h */
136 #include <linux/ethtool.h>
137 #ifndef BOND_ABI_VERSION
138 # define BOND_ABI_VERSION 2
146 struct ifreq mtu, flags, hwaddr;
150 enum { skfd = 3 }; /* AF_INET socket for ioctl() calls. */
152 unsigned abi_ver; /* userland - kernel ABI version */
153 smallint hwaddr_set; /* Master's hwaddr is set */
154 struct dev_data master;
155 struct dev_data slave;
157 #define G (*ptr_to_globals)
158 #define abi_ver (G.abi_ver )
159 #define hwaddr_set (G.hwaddr_set)
160 #define master (G.master )
161 #define slave (G.slave )
162 #define INIT_G() do { \
163 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
167 /* NOINLINEs are placed where it results in smaller code (gcc 4.3.1) */
169 static int ioctl_on_skfd(unsigned request, struct ifreq *ifr)
171 return ioctl(skfd, request, ifr);
174 static int set_ifrname_and_do_ioctl(unsigned request, struct ifreq *ifr, const char *ifname)
176 strncpy_IFNAMSIZ(ifr->ifr_name, ifname);
177 return ioctl_on_skfd(request, ifr);
180 static int get_if_settings(char *ifname, struct dev_data *dd)
184 res = set_ifrname_and_do_ioctl(SIOCGIFMTU, &dd->mtu, ifname);
185 res |= set_ifrname_and_do_ioctl(SIOCGIFFLAGS, &dd->flags, ifname);
186 res |= set_ifrname_and_do_ioctl(SIOCGIFHWADDR, &dd->hwaddr, ifname);
191 static int get_slave_flags(char *slave_ifname)
193 return set_ifrname_and_do_ioctl(SIOCGIFFLAGS, &slave.flags, slave_ifname);
196 static int set_hwaddr(char *ifname, struct sockaddr *hwaddr)
200 memcpy(&(ifr.ifr_hwaddr), hwaddr, sizeof(*hwaddr));
201 return set_ifrname_and_do_ioctl(SIOCSIFHWADDR, &ifr, ifname);
204 static int set_mtu(char *ifname, int mtu)
209 return set_ifrname_and_do_ioctl(SIOCSIFMTU, &ifr, ifname);
212 static int set_if_flags(char *ifname, int flags)
216 ifr.ifr_flags = flags;
217 return set_ifrname_and_do_ioctl(SIOCSIFFLAGS, &ifr, ifname);
220 static int set_if_up(char *ifname, int flags)
222 int res = set_if_flags(ifname, flags | IFF_UP);
224 bb_perror_msg("%s: can't up", ifname);
228 static int set_if_down(char *ifname, int flags)
230 int res = set_if_flags(ifname, flags & ~IFF_UP);
232 bb_perror_msg("%s: can't down", ifname);
236 static int clear_if_addr(char *ifname)
240 ifr.ifr_addr.sa_family = AF_INET;
241 memset(ifr.ifr_addr.sa_data, 0, sizeof(ifr.ifr_addr.sa_data));
242 return set_ifrname_and_do_ioctl(SIOCSIFADDR, &ifr, ifname);
245 static int set_if_addr(char *master_ifname, char *slave_ifname)
247 #if (SIOCGIFADDR | SIOCSIFADDR \
248 | SIOCGIFDSTADDR | SIOCSIFDSTADDR \
249 | SIOCGIFBRDADDR | SIOCSIFBRDADDR \
250 | SIOCGIFNETMASK | SIOCSIFNETMASK) <= 0xffff
255 static const struct {
259 { SIOCGIFADDR, SIOCSIFADDR },
260 { SIOCGIFDSTADDR, SIOCSIFDSTADDR },
261 { SIOCGIFBRDADDR, SIOCSIFBRDADDR },
262 { SIOCGIFNETMASK, SIOCSIFNETMASK },
269 for (i = 0; i < ARRAY_SIZE(ifra); i++) {
270 res = set_ifrname_and_do_ioctl(ifra[i].g_ioctl, &ifr, master_ifname);
272 ifr.ifr_addr.sa_family = AF_INET;
273 memset(ifr.ifr_addr.sa_data, 0,
274 sizeof(ifr.ifr_addr.sa_data));
277 res = set_ifrname_and_do_ioctl(ifra[i].s_ioctl, &ifr, slave_ifname);
285 static void change_active(char *master_ifname, char *slave_ifname)
289 if (!(slave.flags.ifr_flags & IFF_SLAVE)) {
290 bb_error_msg_and_die("%s is not a slave", slave_ifname);
293 strncpy_IFNAMSIZ(ifr.ifr_slave, slave_ifname);
294 if (set_ifrname_and_do_ioctl(SIOCBONDCHANGEACTIVE, &ifr, master_ifname)
295 && ioctl_on_skfd(BOND_CHANGE_ACTIVE_OLD, &ifr)
297 bb_perror_msg_and_die(
298 "master %s, slave %s: can't "
300 master_ifname, slave_ifname);
304 static NOINLINE int enslave(char *master_ifname, char *slave_ifname)
309 if (slave.flags.ifr_flags & IFF_SLAVE) {
311 "%s is already a slave",
316 res = set_if_down(slave_ifname, slave.flags.ifr_flags);
321 /* Older bonding versions would panic if the slave has no IP
322 * address, so get the IP setting from the master.
324 res = set_if_addr(master_ifname, slave_ifname);
326 bb_perror_msg("%s: can't set address", slave_ifname);
330 res = clear_if_addr(slave_ifname);
332 bb_perror_msg("%s: can't clear address", slave_ifname);
337 if (master.mtu.ifr_mtu != slave.mtu.ifr_mtu) {
338 res = set_mtu(slave_ifname, master.mtu.ifr_mtu);
340 bb_perror_msg("%s: can't set MTU", slave_ifname);
346 /* Master already has an hwaddr
347 * so set it's hwaddr to the slave
350 /* The driver is using an old ABI, so
351 * the application sets the slave's
354 if (set_hwaddr(slave_ifname, &(master.hwaddr.ifr_hwaddr))) {
355 bb_perror_msg("%s: can't set hw address",
360 /* For old ABI the application needs to bring the
363 if (set_if_up(slave_ifname, slave.flags.ifr_flags))
366 /* The driver is using a new ABI,
367 * so the driver takes care of setting
368 * the slave's hwaddr and bringing
372 /* No hwaddr for master yet, so
373 * set the slave's hwaddr to it
376 /* For old ABI, the master needs to be
377 * down before setting it's hwaddr
379 if (set_if_down(master_ifname, master.flags.ifr_flags))
383 if (set_hwaddr(master_ifname, &(slave.hwaddr.ifr_hwaddr))) {
384 bb_error_msg("%s: can't set hw address",
390 /* For old ABI, bring the master
393 if (set_if_up(master_ifname, master.flags.ifr_flags))
394 goto undo_master_mac;
400 /* Do the real thing */
401 strncpy_IFNAMSIZ(ifr.ifr_slave, slave_ifname);
402 if (set_ifrname_and_do_ioctl(SIOCBONDENSLAVE, &ifr, master_ifname)
403 && ioctl_on_skfd(BOND_ENSLAVE_OLD, &ifr)
405 goto undo_master_mac;
410 /* rollback (best effort) */
412 set_hwaddr(master_ifname, &(master.hwaddr.ifr_hwaddr));
417 set_hwaddr(slave_ifname, &(slave.hwaddr.ifr_hwaddr));
419 set_mtu(slave_ifname, slave.mtu.ifr_mtu);
423 static int release(char *master_ifname, char *slave_ifname)
428 if (!(slave.flags.ifr_flags & IFF_SLAVE)) {
429 bb_error_msg("%s is not a slave", slave_ifname);
433 strncpy_IFNAMSIZ(ifr.ifr_slave, slave_ifname);
434 if (set_ifrname_and_do_ioctl(SIOCBONDRELEASE, &ifr, master_ifname) < 0
435 && ioctl_on_skfd(BOND_RELEASE_OLD, &ifr) < 0
440 /* The driver is using an old ABI, so we'll set the interface
441 * down to avoid any conflicts due to same MAC/IP
443 res = set_if_down(slave_ifname, slave.flags.ifr_flags);
446 /* set to default mtu */
447 set_mtu(slave_ifname, 1500);
452 static NOINLINE void get_drv_info(char *master_ifname)
455 struct ethtool_drvinfo info;
457 memset(&ifr, 0, sizeof(ifr));
458 ifr.ifr_data = (caddr_t)&info;
459 info.cmd = ETHTOOL_GDRVINFO;
460 /* both fields are 32 bytes long (long enough) */
461 strcpy(info.driver, "ifenslave");
462 strcpy(info.fw_version, utoa(BOND_ABI_VERSION));
463 if (set_ifrname_and_do_ioctl(SIOCETHTOOL, &ifr, master_ifname) < 0) {
464 if (errno == EOPNOTSUPP)
466 bb_perror_msg_and_die("%s: SIOCETHTOOL error", master_ifname);
469 abi_ver = bb_strtou(info.fw_version, NULL, 0);
471 bb_error_msg_and_die("%s: SIOCETHTOOL error", master_ifname);
474 int ifenslave_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
475 int ifenslave_main(int argc UNUSED_PARAM, char **argv)
477 char *master_ifname, *slave_ifname;
487 static const char ifenslave_longopts[] ALIGN1 =
488 "change-active\0" No_argument "c"
489 "detach\0" No_argument "d"
490 "force\0" No_argument "f"
491 /* "all-interfaces\0" No_argument "a" */
494 applet_long_options = ifenslave_longopts;
498 opt = getopt32(argv, "cdfa");
500 if (opt & (opt-1)) /* Only one option can be given */
503 master_ifname = *argv++;
505 /* No interface names - show all interfaces. */
506 if (!master_ifname) {
507 display_interfaces(NULL);
511 /* Open a basic socket */
512 xmove_fd(xsocket(AF_INET, SOCK_DGRAM, 0), skfd);
514 /* Exchange abi version with bonding module */
515 get_drv_info(master_ifname);
517 slave_ifname = *argv++;
519 if (opt & (OPT_d|OPT_c)) {
520 /* --change or --detach, and no slaves given -
521 * show all interfaces. */
522 display_interfaces(slave_ifname /* == NULL */);
523 return 2; /* why 2? */
525 /* A single arg means show the
526 * configuration for this interface
528 display_interfaces(master_ifname);
532 if (get_if_settings(master_ifname, &master)) {
533 /* Probably a good reason not to go on */
534 bb_perror_msg_and_die("%s: can't get settings", master_ifname);
537 /* Check if master is indeed a master;
538 * if not then fail any operation
540 if (!(master.flags.ifr_flags & IFF_MASTER))
541 bb_error_msg_and_die("%s is not a master", master_ifname);
543 /* Check if master is up; if not then fail any operation */
544 if (!(master.flags.ifr_flags & IFF_UP))
545 bb_error_msg_and_die("%s is not up", master_ifname);
548 /* Neither -c[hange] nor -d[etach] -> it's "enslave" then;
549 * and -f[orce] is not there too. Check that it's ethernet. */
550 if (!(opt & (OPT_d|OPT_c|OPT_f)) {
551 /* The family '1' is ARPHRD_ETHER for ethernet. */
552 if (master.hwaddr.ifr_hwaddr.sa_family != 1) {
553 bb_error_msg_and_die(
554 "%s is not ethernet-like (-f overrides)",
560 /* Accepts only one slave */
562 /* Change active slave */
563 if (get_slave_flags(slave_ifname)) {
564 bb_perror_msg_and_die(
565 "%s: can't get flags", slave_ifname);
567 change_active(master_ifname, slave_ifname);
571 /* Accepts multiple slaves */
575 /* Detach a slave interface from the master */
576 rv = get_slave_flags(slave_ifname);
578 /* Can't work with this slave, */
579 /* remember the error and skip it */
581 "skipping %s: can't get flags",
586 rv = release(master_ifname, slave_ifname);
588 bb_perror_msg("can't release %s from %s",
589 slave_ifname, master_ifname);
593 /* Attach a slave interface to the master */
594 rv = get_if_settings(slave_ifname, &slave);
596 /* Can't work with this slave, */
597 /* remember the error and skip it */
599 "skipping %s: can't get settings",
604 rv = enslave(master_ifname, slave_ifname);
606 bb_perror_msg("can't enslave %s to %s",
607 slave_ifname, master_ifname);
611 } while ((slave_ifname = *argv++) != NULL);
613 if (ENABLE_FEATURE_CLEAN_UP) {