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_arp.h>
104 #include <linux/if_bonding.h>
105 #include <linux/sockios.h>
107 typedef unsigned long long u64; /* hack, so we may include kernel's ethtool.h */
108 typedef uint32_t u32; /* ditto */
109 typedef uint16_t u16; /* ditto */
110 typedef uint8_t u8; /* ditto */
111 #include <linux/ethtool.h>
115 struct ifreq mtu, flags, hwaddr;
119 enum { skfd = 3 }; /* AF_INET socket for ioctl() calls. */
121 unsigned abi_ver; /* userland - kernel ABI version */
122 smallint hwaddr_set; /* Master's hwaddr is set */
123 struct dev_data master;
124 struct dev_data slave;
126 #define G (*ptr_to_globals)
127 #define abi_ver (G.abi_ver )
128 #define hwaddr_set (G.hwaddr_set)
129 #define master (G.master )
130 #define slave (G.slave )
131 #define INIT_G() do { \
132 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
136 static void get_drv_info(char *master_ifname);
137 static int get_if_settings(char *ifname, struct dev_data *dd);
138 static int get_slave_flags(char *slave_ifname);
139 static int set_hwaddr(char *ifname, struct sockaddr *hwaddr);
140 static int set_mtu(char *ifname, int mtu);
141 static int set_if_flags(char *ifname, int flags);
142 static int set_if_up(char *ifname, int flags);
143 static int set_if_down(char *ifname, int flags);
144 static int clear_if_addr(char *ifname);
145 static int set_if_addr(char *master_ifname, char *slave_ifname);
146 static void change_active(char *master_ifname, char *slave_ifname);
147 static int enslave(char *master_ifname, char *slave_ifname);
148 static int release(char *master_ifname, char *slave_ifname);
150 static void strncpy_IFNAMSIZ(char *dst, const char *src)
152 strncpy(dst, src, IFNAMSIZ);
155 static int ioctl_on_skfd(unsigned request, struct ifreq *ifr)
157 return ioctl(skfd, request, ifr);
160 static int set_ifrname_and_do_ioctl(unsigned request, struct ifreq *ifr, const char *ifname)
162 strncpy_IFNAMSIZ(ifr->ifr_name, ifname);
163 return ioctl_on_skfd(request, ifr);
166 int ifenslave_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
167 int ifenslave_main(int argc ATTRIBUTE_UNUSED, char **argv)
169 char *master_ifname, *slave_ifname;
178 #if ENABLE_GETOPT_LONG
179 static const char ifenslave_longopts[] ALIGN1 =
180 "change-active\0" No_argument "c"
181 "detach\0" No_argument "d"
182 "force\0" No_argument "f"
185 applet_long_options = ifenslave_longopts;
189 opt = getopt32(argv, "cdf");
191 if (opt & (opt-1)) /* options check */
194 master_ifname = *argv++;
196 /* No interface names - show all interfaces. */
197 if (!master_ifname) {
198 display_interfaces(NULL);
202 /* Open a basic socket */
203 xmove_fd(xsocket(AF_INET, SOCK_DGRAM, 0), skfd);
205 /* Exchange abi version with bonding module */
206 get_drv_info(master_ifname);
208 slave_ifname = *argv++;
210 if (opt & (OPT_d|OPT_c)) {
211 /* --change or --detach, and no slaves given -
212 * show all interfaces. */
213 display_interfaces(slave_ifname /* == NULL */);
214 return 2; /* why 2? */
216 /* A single arg means show the
217 * configuration for this interface
219 display_interfaces(master_ifname);
223 res = get_if_settings(master_ifname, &master);
225 /* Probably a good reason not to go on */
226 bb_perror_msg_and_die("%s: can't get settings", master_ifname);
229 /* check if master is indeed a master;
230 * if not then fail any operation
232 if (!(master.flags.ifr_flags & IFF_MASTER))
233 bb_error_msg_and_die("%s is not a master", master_ifname);
235 /* check if master is up; if not then fail any operation */
236 if (!(master.flags.ifr_flags & IFF_UP))
237 bb_error_msg_and_die("%s is not up", master_ifname);
239 /* No opts: neither -c[hange] nor -d[etach] -> it's "enslave" then;
240 * and -f[orce] is not there too */
242 /* The family '1' is ARPHRD_ETHER for ethernet. */
243 if (master.hwaddr.ifr_hwaddr.sa_family != 1) {
244 bb_error_msg_and_die(
245 "%s is not ethernet-like (-f overrides)",
250 /* Accepts only one slave */
252 /* change active slave */
253 if (get_slave_flags(slave_ifname)) {
254 bb_perror_msg_and_die(
255 "%s: can't get flags", slave_ifname);
257 change_active(master_ifname, slave_ifname);
261 /* Accept multiple slaves */
265 /* detach a slave interface from the master */
266 rv = get_slave_flags(slave_ifname);
268 /* Can't work with this slave, */
269 /* remember the error and skip it */
271 "skipping %s: can't get flags",
276 rv = release(master_ifname, slave_ifname);
279 "master %s, slave %s: "
281 master_ifname, slave_ifname);
285 /* attach a slave interface to the master */
286 rv = get_if_settings(slave_ifname, &slave);
288 /* Can't work with this slave, */
289 /* remember the error and skip it */
291 "skipping %s: can't get settings",
296 rv = enslave(master_ifname, slave_ifname);
299 "master %s, slave %s: "
301 master_ifname, slave_ifname);
305 } while ((slave_ifname = *argv++) != NULL);
307 if (ENABLE_FEATURE_CLEAN_UP) {
314 static void get_drv_info(char *master_ifname)
317 struct ethtool_drvinfo info;
319 memset(&ifr, 0, sizeof(ifr));
320 ifr.ifr_data = (caddr_t)&info;
321 info.cmd = ETHTOOL_GDRVINFO;
322 strncpy(info.driver, "ifenslave", 32);
323 snprintf(info.fw_version, 32, "%d", BOND_ABI_VERSION);
324 if (set_ifrname_and_do_ioctl(SIOCETHTOOL, &ifr, master_ifname) < 0) {
325 if (errno == EOPNOTSUPP)
327 bb_perror_msg_and_die("%s: SIOCETHTOOL error", master_ifname);
330 abi_ver = bb_strtou(info.fw_version, NULL, 0);
332 bb_error_msg_and_die("%s: SIOCETHTOOL error", master_ifname);
335 static void change_active(char *master_ifname, char *slave_ifname)
339 if (!(slave.flags.ifr_flags & IFF_SLAVE)) {
340 bb_error_msg_and_die(
345 strncpy_IFNAMSIZ(ifr.ifr_slave, slave_ifname);
346 if (set_ifrname_and_do_ioctl(SIOCBONDCHANGEACTIVE, &ifr, master_ifname)
347 && ioctl_on_skfd(BOND_CHANGE_ACTIVE_OLD, &ifr)
349 bb_perror_msg_and_die(
350 "master %s, slave %s: can't "
352 master_ifname, slave_ifname);
356 static int enslave(char *master_ifname, char *slave_ifname)
361 if (slave.flags.ifr_flags & IFF_SLAVE) {
363 "%s is already a slave",
368 res = set_if_down(slave_ifname, slave.flags.ifr_flags);
373 /* Older bonding versions would panic if the slave has no IP
374 * address, so get the IP setting from the master.
376 res = set_if_addr(master_ifname, slave_ifname);
378 bb_perror_msg("%s: can't set address", slave_ifname);
382 res = clear_if_addr(slave_ifname);
384 bb_perror_msg("%s: can't clear address", slave_ifname);
389 if (master.mtu.ifr_mtu != slave.mtu.ifr_mtu) {
390 res = set_mtu(slave_ifname, master.mtu.ifr_mtu);
392 bb_perror_msg("%s: can't set MTU", slave_ifname);
398 /* Master already has an hwaddr
399 * so set it's hwaddr to the slave
402 /* The driver is using an old ABI, so
403 * the application sets the slave's
406 if (set_hwaddr(slave_ifname, &(master.hwaddr.ifr_hwaddr))) {
407 bb_perror_msg("%s: can't set hw address",
412 /* For old ABI the application needs to bring the
415 if (set_if_up(slave_ifname, slave.flags.ifr_flags))
418 /* The driver is using a new ABI,
419 * so the driver takes care of setting
420 * the slave's hwaddr and bringing
424 /* No hwaddr for master yet, so
425 * set the slave's hwaddr to it
428 /* For old ABI, the master needs to be
429 * down before setting it's hwaddr
431 if (set_if_down(master_ifname, master.flags.ifr_flags))
435 if (set_hwaddr(master_ifname, &(slave.hwaddr.ifr_hwaddr))) {
436 bb_error_msg("%s: can't set hw address",
442 /* For old ABI, bring the master
445 if (set_if_up(master_ifname, master.flags.ifr_flags))
446 goto undo_master_mac;
452 /* Do the real thing */
453 strncpy_IFNAMSIZ(ifr.ifr_slave, slave_ifname);
454 if (set_ifrname_and_do_ioctl(SIOCBONDENSLAVE, &ifr, master_ifname)
455 && ioctl_on_skfd(BOND_ENSLAVE_OLD, &ifr)
457 goto undo_master_mac;
462 /* rollback (best effort) */
464 set_hwaddr(master_ifname, &(master.hwaddr.ifr_hwaddr));
469 set_hwaddr(slave_ifname, &(slave.hwaddr.ifr_hwaddr));
471 set_mtu(slave_ifname, slave.mtu.ifr_mtu);
475 static int release(char *master_ifname, char *slave_ifname)
480 if (!(slave.flags.ifr_flags & IFF_SLAVE)) {
481 bb_error_msg("%s is not a slave",
486 strncpy_IFNAMSIZ(ifr.ifr_slave, slave_ifname);
487 if (set_ifrname_and_do_ioctl(SIOCBONDRELEASE, &ifr, master_ifname) < 0
488 && ioctl_on_skfd(BOND_RELEASE_OLD, &ifr) < 0
493 /* The driver is using an old ABI, so we'll set the interface
494 * down to avoid any conflicts due to same MAC/IP
496 res = set_if_down(slave_ifname, slave.flags.ifr_flags);
499 /* set to default mtu */
500 set_mtu(slave_ifname, 1500);
505 static int get_if_settings(char *ifname, struct dev_data *dd)
509 res = set_ifrname_and_do_ioctl(SIOCGIFMTU, &dd->mtu, ifname);
510 res |= set_ifrname_and_do_ioctl(SIOCGIFFLAGS, &dd->flags, ifname);
511 res |= set_ifrname_and_do_ioctl(SIOCGIFHWADDR, &dd->hwaddr, ifname);
516 static int get_slave_flags(char *slave_ifname)
518 return set_ifrname_and_do_ioctl(SIOCGIFFLAGS, &slave.flags, slave_ifname);
521 static int set_hwaddr(char *ifname, struct sockaddr *hwaddr)
525 memcpy(&(ifr.ifr_hwaddr), hwaddr, sizeof(*hwaddr));
526 return set_ifrname_and_do_ioctl(SIOCSIFHWADDR, &ifr, ifname);
529 static int set_mtu(char *ifname, int mtu)
534 return set_ifrname_and_do_ioctl(SIOCSIFMTU, &ifr, ifname);
537 static int set_if_flags(char *ifname, int flags)
541 ifr.ifr_flags = flags;
542 return set_ifrname_and_do_ioctl(SIOCSIFFLAGS, &ifr, ifname);
545 static int set_if_up(char *ifname, int flags)
547 int res = set_if_flags(ifname, flags | IFF_UP);
549 bb_perror_msg("%s: can't up", ifname);
553 static int set_if_down(char *ifname, int flags)
555 int res = set_if_flags(ifname, flags & ~IFF_UP);
557 bb_perror_msg("%s: can't down", ifname);
561 static int clear_if_addr(char *ifname)
565 ifr.ifr_addr.sa_family = AF_INET;
566 memset(ifr.ifr_addr.sa_data, 0, sizeof(ifr.ifr_addr.sa_data));
567 return set_ifrname_and_do_ioctl(SIOCSIFADDR, &ifr, ifname);
570 static int set_if_addr(char *master_ifname, char *slave_ifname)
572 #if (SIOCGIFADDR | SIOCSIFADDR \
573 | SIOCGIFDSTADDR | SIOCSIFDSTADDR \
574 | SIOCGIFBRDADDR | SIOCSIFBRDADDR \
575 | SIOCGIFNETMASK | SIOCSIFNETMASK) <= 0xffff
580 static const struct {
584 { SIOCGIFADDR, SIOCSIFADDR },
585 { SIOCGIFDSTADDR, SIOCSIFDSTADDR },
586 { SIOCGIFBRDADDR, SIOCSIFBRDADDR },
587 { SIOCGIFNETMASK, SIOCSIFNETMASK },
594 for (i = 0; i < ARRAY_SIZE(ifra); i++) {
595 res = set_ifrname_and_do_ioctl(ifra[i].g_ioctl, &ifr, master_ifname);
597 ifr.ifr_addr.sa_family = AF_INET;
598 memset(ifr.ifr_addr.sa_data, 0,
599 sizeof(ifr.ifr_addr.sa_data));
602 res = set_ifrname_and_do_ioctl(ifra[i].s_ioctl, &ifr, slave_ifname);