source: branches/3.2/mindi-busybox/networking/ifenslave.c @ 3232

Last change on this file since 3232 was 3232, checked in by bruno, 5 years ago
  • Update mindi-busybox to 1.21.1
  • Property svn:eol-style set to native
File size: 18.0 KB
RevLine 
[2725]1/* Mode: C;
2 *
3 * Mini ifenslave implementation for busybox
4 * Copyright (C) 2005 by Marc Leeman <marc.leeman@barco.com>
5 *
6 * ifenslave.c: Configure network interfaces for parallel routing.
7 *
8 *      This program controls the Linux implementation of running multiple
9 *      network interfaces in parallel.
10 *
11 * Author:      Donald Becker <becker@cesdis.gsfc.nasa.gov>
12 *              Copyright 1994-1996 Donald Becker
13 *
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.
17 *
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
21 *
22 *  Changes :
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
28 *
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.
33 *
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
36 *         at runtime.
37 *
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
42 *         old versions
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
46 *
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).
55 *
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.
65 *
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.
72 *
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.
80 *
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
84 *         processing.
85 *
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.
95 *
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
99 */
100
[3232]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" */
109//usage:
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"
126
[2725]127#include "libbb.h"
128
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
138#endif
139#ifndef IFNAMSIZ
140# define IFNAMSIZ 16
141#endif
142
143
144struct dev_data {
145    struct ifreq mtu, flags, hwaddr;
146};
147
148
149enum { skfd = 3 };      /* AF_INET socket for ioctl() calls. */
150struct globals {
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;
155};
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))); \
163} while (0)
164
165
166/* NOINLINEs are placed where it results in smaller code (gcc 4.3.1) */
167
168static int ioctl_on_skfd(unsigned request, struct ifreq *ifr)
169{
170    return ioctl(skfd, request, ifr);
171}
172
173static int set_ifrname_and_do_ioctl(unsigned request, struct ifreq *ifr, const char *ifname)
174{
175    strncpy_IFNAMSIZ(ifr->ifr_name, ifname);
176    return ioctl_on_skfd(request, ifr);
177}
178
179static int get_if_settings(char *ifname, struct dev_data *dd)
180{
181    int res;
182
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);
186
187    return res;
188}
189
190static int get_slave_flags(char *slave_ifname)
191{
192    return set_ifrname_and_do_ioctl(SIOCGIFFLAGS, &slave.flags, slave_ifname);
193}
194
195static int set_hwaddr(char *ifname, struct sockaddr *hwaddr)
196{
197    struct ifreq ifr;
198
199    memcpy(&(ifr.ifr_hwaddr), hwaddr, sizeof(*hwaddr));
200    return set_ifrname_and_do_ioctl(SIOCSIFHWADDR, &ifr, ifname);
201}
202
203static int set_mtu(char *ifname, int mtu)
204{
205    struct ifreq ifr;
206
207    ifr.ifr_mtu = mtu;
208    return set_ifrname_and_do_ioctl(SIOCSIFMTU, &ifr, ifname);
209}
210
211static int set_if_flags(char *ifname, int flags)
212{
213    struct ifreq ifr;
214
215    ifr.ifr_flags = flags;
216    return set_ifrname_and_do_ioctl(SIOCSIFFLAGS, &ifr, ifname);
217}
218
219static int set_if_up(char *ifname, int flags)
220{
221    int res = set_if_flags(ifname, flags | IFF_UP);
222    if (res)
223        bb_perror_msg("%s: can't up", ifname);
224    return res;
225}
226
227static int set_if_down(char *ifname, int flags)
228{
229    int res = set_if_flags(ifname, flags & ~IFF_UP);
230    if (res)
231        bb_perror_msg("%s: can't down", ifname);
232    return res;
233}
234
235static int clear_if_addr(char *ifname)
236{
237    struct ifreq ifr;
238
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);
242}
243
244static int set_if_addr(char *master_ifname, char *slave_ifname)
245{
246#if (SIOCGIFADDR | SIOCSIFADDR \
247  | SIOCGIFDSTADDR | SIOCSIFDSTADDR \
248  | SIOCGIFBRDADDR | SIOCSIFBRDADDR \
249  | SIOCGIFNETMASK | SIOCSIFNETMASK) <= 0xffff
250#define INT uint16_t
251#else
252#define INT int
253#endif
254    static const struct {
255        INT g_ioctl;
256        INT s_ioctl;
257    } ifra[] = {
258        { SIOCGIFADDR,    SIOCSIFADDR    },
259        { SIOCGIFDSTADDR, SIOCSIFDSTADDR },
260        { SIOCGIFBRDADDR, SIOCSIFBRDADDR },
261        { SIOCGIFNETMASK, SIOCSIFNETMASK },
262    };
263
264    struct ifreq ifr;
265    int res;
266    unsigned i;
267
268    for (i = 0; i < ARRAY_SIZE(ifra); i++) {
269        res = set_ifrname_and_do_ioctl(ifra[i].g_ioctl, &ifr, master_ifname);
270        if (res < 0) {
271            ifr.ifr_addr.sa_family = AF_INET;
272            memset(ifr.ifr_addr.sa_data, 0,
[3232]273                sizeof(ifr.ifr_addr.sa_data));
[2725]274        }
275
276        res = set_ifrname_and_do_ioctl(ifra[i].s_ioctl, &ifr, slave_ifname);
277        if (res < 0)
278            return res;
279    }
280
281    return 0;
282}
283
284static void change_active(char *master_ifname, char *slave_ifname)
285{
286    struct ifreq ifr;
287
288    if (!(slave.flags.ifr_flags & IFF_SLAVE)) {
289        bb_error_msg_and_die("%s is not a slave", slave_ifname);
290    }
291
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)
295    ) {
296        bb_perror_msg_and_die(
297            "master %s, slave %s: can't "
298            "change active",
299            master_ifname, slave_ifname);
300    }
301}
302
303static NOINLINE int enslave(char *master_ifname, char *slave_ifname)
304{
305    struct ifreq ifr;
306    int res;
307
308    if (slave.flags.ifr_flags & IFF_SLAVE) {
309        bb_error_msg(
310            "%s is already a slave",
311            slave_ifname);
312        return 1;
313    }
314
315    res = set_if_down(slave_ifname, slave.flags.ifr_flags);
316    if (res)
317        return res;
318
319    if (abi_ver < 2) {
320        /* Older bonding versions would panic if the slave has no IP
321         * address, so get the IP setting from the master.
322         */
323        res = set_if_addr(master_ifname, slave_ifname);
324        if (res) {
325            bb_perror_msg("%s: can't set address", slave_ifname);
326            return res;
327        }
328    } else {
329        res = clear_if_addr(slave_ifname);
330        if (res) {
331            bb_perror_msg("%s: can't clear address", slave_ifname);
332            return res;
333        }
334    }
335
336    if (master.mtu.ifr_mtu != slave.mtu.ifr_mtu) {
337        res = set_mtu(slave_ifname, master.mtu.ifr_mtu);
338        if (res) {
339            bb_perror_msg("%s: can't set MTU", slave_ifname);
340            return res;
341        }
342    }
343
344    if (hwaddr_set) {
345        /* Master already has an hwaddr
346         * so set it's hwaddr to the slave
347         */
348        if (abi_ver < 1) {
349            /* The driver is using an old ABI, so
350             * the application sets the slave's
351             * hwaddr
352             */
353            if (set_hwaddr(slave_ifname, &(master.hwaddr.ifr_hwaddr))) {
354                bb_perror_msg("%s: can't set hw address",
355                        slave_ifname);
356                goto undo_mtu;
357            }
358
359            /* For old ABI the application needs to bring the
360             * slave back up
361             */
362            if (set_if_up(slave_ifname, slave.flags.ifr_flags))
363                goto undo_slave_mac;
364        }
365        /* The driver is using a new ABI,
366         * so the driver takes care of setting
367         * the slave's hwaddr and bringing
368         * it up again
369         */
370    } else {
371        /* No hwaddr for master yet, so
372         * set the slave's hwaddr to it
373         */
374        if (abi_ver < 1) {
375            /* For old ABI, the master needs to be
376             * down before setting it's hwaddr
377             */
378            if (set_if_down(master_ifname, master.flags.ifr_flags))
379                goto undo_mtu;
380        }
381
382        if (set_hwaddr(master_ifname, &(slave.hwaddr.ifr_hwaddr))) {
383            bb_error_msg("%s: can't set hw address",
384                master_ifname);
385            goto undo_mtu;
386        }
387
388        if (abi_ver < 1) {
389            /* For old ABI, bring the master
390             * back up
391             */
392            if (set_if_up(master_ifname, master.flags.ifr_flags))
393                goto undo_master_mac;
394        }
395
396        hwaddr_set = 1;
397    }
398
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)
403    ) {
404        goto undo_master_mac;
405    }
406
407    return 0;
408
409/* rollback (best effort) */
410 undo_master_mac:
411    set_hwaddr(master_ifname, &(master.hwaddr.ifr_hwaddr));
412    hwaddr_set = 0;
413    goto undo_mtu;
414
415 undo_slave_mac:
416    set_hwaddr(slave_ifname, &(slave.hwaddr.ifr_hwaddr));
417 undo_mtu:
418    set_mtu(slave_ifname, slave.mtu.ifr_mtu);
419    return 1;
420}
421
422static int release(char *master_ifname, char *slave_ifname)
423{
424    struct ifreq ifr;
425    int res = 0;
426
427    if (!(slave.flags.ifr_flags & IFF_SLAVE)) {
428        bb_error_msg("%s is not a slave", slave_ifname);
429        return 1;
430    }
431
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
435    ) {
436        return 1;
437    }
438    if (abi_ver < 1) {
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
441         */
442        res = set_if_down(slave_ifname, slave.flags.ifr_flags);
443    }
444
445    /* set to default mtu */
446    set_mtu(slave_ifname, 1500);
447
448    return res;
449}
450
451static NOINLINE void get_drv_info(char *master_ifname)
452{
453    struct ifreq ifr;
454    struct ethtool_drvinfo info;
455
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)
464            return;
465        bb_perror_msg_and_die("%s: SIOCETHTOOL error", master_ifname);
466    }
467
468    abi_ver = bb_strtou(info.fw_version, NULL, 0);
469    if (errno)
470        bb_error_msg_and_die("%s: SIOCETHTOOL error", master_ifname);
471}
472
473int ifenslave_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
474int ifenslave_main(int argc UNUSED_PARAM, char **argv)
475{
476    char *master_ifname, *slave_ifname;
477    int rv;
478    int res;
479    unsigned opt;
480    enum {
481        OPT_c = (1 << 0),
482        OPT_d = (1 << 1),
483        OPT_f = (1 << 2),
484    };
485#if ENABLE_LONG_OPTS
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" */
491        ;
492
493    applet_long_options = ifenslave_longopts;
494#endif
495    INIT_G();
496
497    opt = getopt32(argv, "cdfa");
498    argv += optind;
499    if (opt & (opt-1)) /* Only one option can be given */
500        bb_show_usage();
501
502    master_ifname = *argv++;
503
504    /* No interface names - show all interfaces. */
505    if (!master_ifname) {
506        display_interfaces(NULL);
507        return EXIT_SUCCESS;
508    }
509
510    /* Open a basic socket */
511    xmove_fd(xsocket(AF_INET, SOCK_DGRAM, 0), skfd);
512
513    /* Exchange abi version with bonding module */
514    get_drv_info(master_ifname);
515
516    slave_ifname = *argv++;
517    if (!slave_ifname) {
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? */
523        }
524        /* A single arg means show the
525         * configuration for this interface
526         */
527        display_interfaces(master_ifname);
528        return EXIT_SUCCESS;
529    }
530
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);
534    }
535
536    /* Check if master is indeed a master;
537     * if not then fail any operation
538     */
539    if (!(master.flags.ifr_flags & IFF_MASTER))
540        bb_error_msg_and_die("%s is not a master", master_ifname);
541
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);
545
546#ifdef WHY_BOTHER
547    /* Neither -c[hange] nor -d[etach] -> it's "enslave" then;
548     * and -f[orce] is not there too. Check that it's ethernet. */
[3232]549    if (!(opt & (OPT_d|OPT_c|OPT_f))) {
[2725]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)",
554                master_ifname);
555        }
556    }
557#endif
558
559    /* Accepts only one slave */
560    if (opt & OPT_c) {
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);
565        }
566        change_active(master_ifname, slave_ifname);
567        return EXIT_SUCCESS;
568    }
569
570    /* Accepts multiple slaves */
571    res = 0;
572    do {
573        if (opt & OPT_d) {
574            /* Detach a slave interface from the master */
575            rv = get_slave_flags(slave_ifname);
576            if (rv) {
577                /* Can't work with this slave, */
578                /* remember the error and skip it */
579                bb_perror_msg(
580                    "skipping %s: can't get flags",
581                    slave_ifname);
582                res = rv;
583                continue;
584            }
585            rv = release(master_ifname, slave_ifname);
586            if (rv) {
587                bb_perror_msg("can't release %s from %s",
588                    slave_ifname, master_ifname);
589                res = rv;
590            }
591        } else {
592            /* Attach a slave interface to the master */
593            rv = get_if_settings(slave_ifname, &slave);
594            if (rv) {
595                /* Can't work with this slave, */
596                /* remember the error and skip it */
597                bb_perror_msg(
598                    "skipping %s: can't get settings",
599                    slave_ifname);
600                res = rv;
601                continue;
602            }
603            rv = enslave(master_ifname, slave_ifname);
604            if (rv) {
605                bb_perror_msg("can't enslave %s to %s",
606                    slave_ifname, master_ifname);
607                res = rv;
608            }
609        }
610    } while ((slave_ifname = *argv++) != NULL);
611
612    if (ENABLE_FEATURE_CLEAN_UP) {
613        close(skfd);
614    }
615
616    return res;
617}
Note: See TracBrowser for help on using the repository browser.