/* Mode: C;
* ifenslave.c: Configure network interfaces for parallel routing.
*
* This program controls the Linux implementation of running multiple
* network interfaces in parallel.
*
* Usage: ifenslave [-v] master-interface < slave-interface [metric <N>] > ...
*
* Author: Donald Becker <becker@cesdis.gsfc.nasa.gov>
* Copyright 1994-1996 Donald Becker
*
* This program is free software; you can redistribute it
* and/or modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation.
*
* The author may be reached as becker@CESDIS.gsfc.nasa.gov, or C/O
* Center of Excellence in Space Data and Information Sciences
* Code 930.5, Goddard Space Flight Center, Greenbelt MD 20771
*
* Changes :
* - 2000/10/02 Willy Tarreau <willy at meta-x.org> :
* - few fixes. Master's MAC address is now correctly taken from
* the first device when not previously set ;
* - detach support : call BOND_RELEASE to detach an enslaved interface.
* - give a mini-howto from command-line help : # ifenslave -h
*
* - 2001/02/16 Chad N. Tindel <ctindel at ieee dot org> :
* - Master is now brought down before setting the MAC address. In
* the 2.4 kernel you can't change the MAC address while the device is
* up because you get EBUSY.
*
* - 2001/09/13 Takao Indoh <indou dot takao at jp dot fujitsu dot com>
* - Added the ability to change the active interface on a mode 1 bond
* at runtime.
*
* - 2001/10/23 Chad N. Tindel <ctindel at ieee dot org> :
* - No longer set the MAC address of the master. The bond device will
* take care of this itself
* - Try the SIOC*** versions of the bonding ioctls before using the
* old versions
* - 2002/02/18 Erik Habbinga <erik_habbinga @ hp dot com> :
* - ifr2.ifr_flags was not initialized in the hwaddr_notset case,
* SIOCGIFFLAGS now called before hwaddr_notset test
*
* - 2002/10/31 Tony Cureington <tony.cureington * hp_com> :
* - If the master does not have a hardware address when the first slave
* is enslaved, the master is assigned the hardware address of that
* slave - there is a comment in bonding.c stating "ifenslave takes
* care of this now." This corrects the problem of slaves having
* different hardware addresses in active-backup mode when
* multiple interfaces are specified on a single ifenslave command
* (ifenslave bond0 eth0 eth1).
*
* - 2003/03/18 - Tsippy Mendelson <tsippy.mendelson at intel dot com> and
* Shmulik Hen <shmulik.hen at intel dot com>
* - Moved setting the slave's mac address and openning it, from
* the application to the driver. This enables support of modes
* that need to use the unique mac address of each slave.
* The driver also takes care of closing the slave and restoring its
* original mac address upon release.
* In addition, block possibility of enslaving before the master is up.
* This prevents putting the system in an undefined state.
*/
static char *version =
"ifenslave.c:v0.07 9/9/97 Donald Becker (becker@cesdis.gsfc.nasa.gov).\n"
"detach support added on 2000/10/02 by Willy Tarreau (willy at meta-x.org).\n"
"2.4 kernel support added on 2001/02/16 by Chad N. Tindel (ctindel at ieee dot org.\n";
static const char *usage_msg =
"Usage: ifenslave [-adfrvVh] <master-interface> < <slave-if> [metric <N>] > ...\n"
" ifenslave -c master-interface slave-if\n";
static const char *howto_msg =
"Usage: ifenslave [-adfrvVh] <master-interface> < <slave-if> [metric <N>] > ...\n"
" ifenslave -c master-interface slave-if\n"
"\n"
" To create a bond device, simply follow these three steps :\n"
" - ensure that the required drivers are properly loaded :\n"
" # modprobe bonding ; modprobe <3c59x|eepro100|pcnet32|tulip|...>\n"
" - assign an IP address to the bond device :\n"
" # ifconfig bond0 <addr> netmask <mask> broadcast <bcast>\n"
" - attach all the interfaces you need to the bond device :\n"
" # ifenslave bond0 eth0 eth1 eth2\n"
" If bond0 didn't have a MAC address, it will take eth0's. Then, all\n"
" interfaces attached AFTER this assignment will get the same MAC addr.\n"
"\n"
" To detach a dead interface without setting the bond device down :\n"
" # ifenslave -d bond0 eth1\n"
"\n"
" To set the bond device down and automatically release all the slaves :\n"
" # ifconfig bond0 down\n"
"\n"
" To change active slave :\n"
" # ifenslave -c bond0 eth0\n"
"\n";
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <linux/if.h>
#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/if_bonding.h>
#include <linux/sockios.h>
struct option longopts[] = {
/* { name has_arg *flag val } */
{"all-interfaces", 0, 0, 'a'}, /* Show all interfaces. */
{"force", 0, 0, 'f'}, /* Force the operation. */
{"help", 0, 0, '?'}, /* Give help */
{"howto", 0, 0, 'h'}, /* Give some more help */
{"receive-slave", 0, 0, 'r'}, /* Make a receive-only slave. */
{"verbose", 0, 0, 'v'}, /* Report each action taken. */
{"version", 0, 0, 'V'}, /* Emit version information. */
{"detach", 0, 0, 'd'}, /* Detach a slave interface. */
{"change-active", 0, 0, 'c'}, /* Change the active slave. */
{ 0, 0, 0, 0 }
};
/* Command-line flags. */
unsigned int
opt_a = 0, /* Show-all-interfaces flag. */
opt_f = 0, /* Force the operation. */
opt_r = 0, /* Set up a Rx-only slave. */
opt_d = 0, /* detach a slave interface. */
opt_c = 0, /* change-active-slave flag. */
verbose = 0, /* Verbose flag. */
opt_version = 0,
opt_howto = 0;
int skfd = -1; /* AF_INET socket for ioctl() calls. */
static void if_print(char *ifname);
int
main(int argc, char **argv)
{
struct ifreq ifr2, if_hwaddr, if_ipaddr, if_metric, if_mtu, if_dstaddr;
struct ifreq if_netmask, if_brdaddr, if_flags;
int goterr = 0;
int c, errflag = 0;
sa_family_t master_family;
char **spp, *master_ifname, *slave_ifname;
int hwaddr_notset;
int master_up;
while ((c = getopt_long(argc, argv, "acdfrvV?h", longopts, 0)) != EOF)
switch (c) {
case 'a': opt_a++; break;
case 'f': opt_f++; break;
case 'r': opt_r++; break;
case 'd': opt_d++; break;
case 'c': opt_c++; break;
case 'v': verbose++; break;
case 'V': opt_version++; break;
case 'h': opt_howto++; break;
case '?': errflag++;
}
/* option check */
if (opt_c)
if(opt_a || opt_f || opt_r || opt_d || verbose || opt_version ||
opt_howto || errflag ) {
fprintf(stderr, usage_msg);
return 2;
}
if (errflag) {
fprintf(stderr, usage_msg);
return 2;
}
if (opt_howto) {
fprintf(stderr, howto_msg);
return 0;
}
if (verbose || opt_version) {
printf(version);
if (opt_version)
exit(0);
}
/* Open a basic socket. */
if ((skfd = socket(AF_INET, SOCK_DGRAM,0)) < 0) {
perror("socket");
exit(-1);
}
if (verbose)
fprintf(stderr, "DEBUG: argc=%d, optind=%d and argv[optind] is %s.\n",
argc, optind, argv[optind]);
/* No remaining args means show all interfaces. */
if (optind == argc) {
if_print((char *)NULL);
(void) close(skfd);
exit(0);
}
/* Copy the interface name. */
spp = argv + optind;
master_ifname = *spp++;
slave_ifname = *spp++;
/* Check command line. */
if (opt_c) {
char **tempp = spp;
if ((master_ifname == NULL)||(slave_ifname == NULL)||(*tempp++ != NULL)) {
fprintf(stderr, usage_msg);
return 2;
}
}
/* A single args means show the configuration for this interface. */
if (slave_ifname == NULL) {
if_print(master_ifname);
(void) close(skfd);
exit(0);
}
/* Get the vitals from the master interface. */
{
struct ifreq *ifra[7] = { &if_ipaddr, &if_mtu, &if_dstaddr,
&if_brdaddr, &if_netmask, &if_flags,
&if_hwaddr };
const char *req_name[7] = {
"IP address", "MTU", "destination address",
"broadcast address", "netmask", "status flags",
"hardware address" };
const int ioctl_req_type[7] = {
SIOCGIFADDR, SIOCGIFMTU, SIOCGIFDSTADDR,
SIOCGIFBRDADDR, SIOCGIFNETMASK, SIOCGIFFLAGS,
SIOCGIFHWADDR };
int i;
for (i = 0; i < 7; i++) {
strncpy(ifra[i]->ifr_name, master_ifname, IFNAMSIZ);
if (ioctl(skfd, ioctl_req_type[i], ifra[i]) < 0) {
fprintf(stderr,
"Something broke getting the master's %s: %s.\n",
req_name[i], strerror(errno));
}
}
hwaddr_notset = 1; /* assume master's address not set yet */
for (i = 0; hwaddr_notset && (i < 6); i++) {
hwaddr_notset &= ((unsigned char *)if_hwaddr.ifr_hwaddr.sa_data)[i] == 0;
}
/* The family '1' is ARPHRD_ETHER for ethernet. */
if (if_hwaddr.ifr_hwaddr.sa_family != 1 && !opt_f) {
fprintf(stderr, "The specified master interface '%s' is not"
" ethernet-like.\n This program is designed to work"
" with ethernet-like network interfaces.\n"
" Use the '-f' option to force the operation.\n",
master_ifname);
exit (1);
}
master_family = if_hwaddr.ifr_hwaddr.sa_family;
if (verbose) {
unsigned char *hwaddr = (unsigned char *)if_hwaddr.ifr_hwaddr.sa_data;
printf("The current hardware address (SIOCGIFHWADDR) of %s is type %d "
"%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x.\n", master_ifname,
if_hwaddr.ifr_hwaddr.sa_family, hwaddr[0], hwaddr[1],
hwaddr[2], hwaddr[3], hwaddr[4], hwaddr[5]);
}
}
/* do this when enslaving interfaces */
do {
if (opt_d) { /* detach a slave interface from the master */
strncpy(if_flags.ifr_name, master_ifname, IFNAMSIZ);
strncpy(if_flags.ifr_slave, slave_ifname, IFNAMSIZ);
if ((ioctl(skfd, SIOCBONDRELEASE, &if_flags) < 0) &&
(ioctl(skfd, BOND_RELEASE_OLD, &if_flags) < 0)) {
fprintf(stderr, "SIOCBONDRELEASE: cannot detach %s from %s. errno=%s.\n",
slave_ifname, master_ifname, strerror(errno));
}
/* the bonding module takes care of restoring the slaves original
* mac address and closing its net device
*/
}
else { /* attach a slave interface to the master */
strncpy(ifr2.ifr_name, slave_ifname, IFNAMSIZ);
if (ioctl(skfd, SIOCGIFFLAGS, &ifr2) < 0) {
int saved_errno = errno;
fprintf(stderr, "SIOCGIFFLAGS on %s failed: %s\n", slave_ifname,
strerror(saved_errno));
return 1;
}
/* if hwaddr_notset, assign the slave hw address to the master */
if (hwaddr_notset) {
/* assign the slave hw address to the
* master since it currently does not
* have one; otherwise, slaves may
* have different hw addresses in
* active-backup mode as seen when enslaving
* using "ifenslave bond0 eth0 eth1" because
* hwaddr_notset is set outside this loop.
* TODO: put this and the "else" portion in
* a function.
*/
goterr = 0;
master_up = 0;
if (if_flags.ifr_flags & IFF_UP) {
if_flags.ifr_flags &= ~IFF_UP;
if (ioctl(skfd, SIOCSIFFLAGS,
&if_flags) < 0) {
goterr = 1;
fprintf(stderr,
"Shutting down "
"interface %s failed: "
"%s\n",
master_ifname,
strerror(errno));
} else {
/* we took the master down,
* so we must bring it up
*/
master_up = 1;
}
} else {
fprintf(stderr, "Cannot enslave; the specified master interface '%s' is not up.\n", master_ifname);
exit (1);
}
if (!goterr) {
/* get the slaves MAC address */
strncpy(if_hwaddr.ifr_name,
slave_ifname, IFNAMSIZ);
if (ioctl(skfd, SIOCGIFHWADDR,
&if_hwaddr) < 0) {
fprintf(stderr,
"Could not get MAC "
"address of %s: %s\n",
slave_ifname,
strerror(errno));
strncpy(if_hwaddr.ifr_name,
master_ifname,
IFNAMSIZ);
goterr=1;
}
}
if (!goterr) {
strncpy(if_hwaddr.ifr_name,
master_ifname, IFNAMSIZ);
if (ioctl(skfd, SIOCSIFHWADDR,
&if_hwaddr) < 0) {
fprintf(stderr,
"Could not set MAC "
"address of %s: %s\n",
master_ifname,
strerror(errno));
goterr=1;
} else {
hwaddr_notset = 0;
}
}
if (master_up) {
if_flags.ifr_flags |= IFF_UP;
if (ioctl(skfd, SIOCSIFFLAGS,
&if_flags) < 0) {
fprintf(stderr,
"Bringing up interface "
"%s failed: %s\n",
master_ifname,
strerror(errno));
}
}
}
/* the bonding module takes care of setting the slave's mac address
* according to the mode requirements.
*/
if (*spp && !strcmp(*spp, "metric")) {
if (*++spp == NULL) {
fprintf(stderr, usage_msg);
exit(2);
}
if_metric.ifr_metric = atoi(*spp);
strncpy(if_metric.ifr_name, slave_ifname, IFNAMSIZ);
if (ioctl(skfd, SIOCSIFMETRIC, &if_metric) < 0) {
fprintf(stderr, "SIOCSIFMETRIC on %s: %s\n", slave_ifname,
strerror(errno));
goterr = 1;
}
spp++;
}
if (strncpy(if_ipaddr.ifr_name, slave_ifname, IFNAMSIZ) <= 0
|| ioctl(skfd, SIOCSIFADDR, &if_ipaddr) < 0) {
fprintf(stderr,
"Something broke setting the slave's address: %s.\n",
strerror(errno));
} else {
if (verbose) {
unsigned char *ipaddr = if_ipaddr.ifr_addr.sa_data;
printf("Set the slave's (%s) IP address to %d.%d.%d.%d.\n",
slave_ifname, ipaddr[0], ipaddr[1], ipaddr[2], ipaddr[3]);
}
}
if (strncpy(if_mtu.ifr_name, slave_ifname, IFNAMSIZ) <= 0
|| ioctl(skfd, SIOCSIFMTU, &if_mtu) < 0) {
fprintf(stderr, "Something broke setting the slave MTU: %s.\n",
strerror(errno));
} else {
if (verbose)
printf("Set the slave's (%s) MTU to %d.\n", slave_ifname, if_mtu.ifr_mtu);
}
if (strncpy(if_dstaddr.ifr_name, slave_ifname, IFNAMSIZ) <= 0
|| ioctl(skfd, SIOCSIFDSTADDR, &if_dstaddr) < 0) {
fprintf(stderr, "Error setting the slave (%s) with SIOCSIFDSTADDR: %s.\n",
slave_ifname, strerror(errno));
} else {
if (verbose) {
unsigned char *ipaddr = if_dstaddr.ifr_dstaddr.sa_data;
printf("Set the slave's (%s) destination address to %d.%d.%d.%d.\n",
slave_ifname, ipaddr[0], ipaddr[1], ipaddr[2], ipaddr[3]);
}
}
if (strncpy(if_brdaddr.ifr_name, slave_ifname, IFNAMSIZ) <= 0
|| ioctl(skfd, SIOCSIFBRDADDR, &if_brdaddr) < 0) {
fprintf(stderr,
"Something broke setting the slave (%s) broadcast address: %s.\n",
slave_ifname, strerror(errno));
} else {
if (verbose) {
unsigned char *ipaddr = if_brdaddr.ifr_broadaddr.sa_data;
printf("Set the slave's (%s) broadcast address to %d.%d.%d.%d.\n",
slave_ifname, ipaddr[0], ipaddr[1], ipaddr[2], ipaddr[3]);
}
}
if (strncpy(if_netmask.ifr_name, slave_ifname, IFNAMSIZ) <= 0
|| ioctl(skfd, SIOCSIFNETMASK, &if_netmask) < 0) {
fprintf(stderr,
"Something broke setting the slave (%s) netmask: %s.\n",
slave_ifname, strerror(errno));
} else {
if (verbose) {
unsigned char *ipaddr = if_netmask.ifr_netmask.sa_data;
printf("Set the slave's (%s) netmask to %d.%d.%d.%d.\n",
slave_ifname, ipaddr[0], ipaddr[1], ipaddr[2], ipaddr[3]);
}
}
/* the bonding module takes care of openning the interface
* after setting its mac address
*/
if (ifr2.ifr_flags & IFF_UP) { // the interface will need to be down
ifr2.ifr_flags &= ~IFF_UP;
if (ioctl(skfd, SIOCSIFFLAGS, &ifr2) < 0) {
int saved_errno = errno;
fprintf(stderr, "Shutting down interface %s failed: %s\n",
slave_ifname, strerror(saved_errno));
}
}
/* Do the real thing */
if ( ! opt_r) {
strncpy(if_flags.ifr_name, master_ifname, IFNAMSIZ);
strncpy(if_flags.ifr_slave, slave_ifname, IFNAMSIZ);
if (!opt_c) {
if ((ioctl(skfd, SIOCBONDENSLAVE, &if_flags) < 0) &&
(ioctl(skfd, BOND_ENSLAVE_OLD, &if_flags) < 0)) {
fprintf(stderr, "SIOCBONDENSLAVE: %s.\n", strerror(errno));
}
}
else {
if ((ioctl(skfd, SIOCBONDCHANGEACTIVE, &if_flags) < 0) &&
(ioctl(skfd, BOND_CHANGE_ACTIVE_OLD, &if_flags) < 0)) {
fprintf(stderr, "SIOCBONDCHANGEACTIVE: %s.\n", strerror(errno));
}
}
}
}
} while ( (slave_ifname = *spp++) != NULL);
/* Close the socket. */
(void) close(skfd);
return(goterr);
}
static short mif_flags;
/* Get the inteface configuration from the kernel. */
static int if_getconfig(char *ifname)
{
struct ifreq ifr;
int metric, mtu; /* Parameters of the master interface. */
struct sockaddr dstaddr, broadaddr, netmask;
strcpy(ifr.ifr_name, ifname);
if (ioctl(skfd, SIOCGIFFLAGS, &ifr) < 0)
return -1;
mif_flags = ifr.ifr_flags;
printf("The result of SIOCGIFFLAGS on %s is %x.\n",
ifname, ifr.ifr_flags);
strcpy(ifr.ifr_name, ifname);
if (ioctl(skfd, SIOCGIFADDR, &ifr) < 0)
return -1;
printf("The result of SIOCGIFADDR is %2.2x.%2.2x.%2.2x.%2.2x.\n",
ifr.ifr_addr.sa_data[0], ifr.ifr_addr.sa_data[1],
ifr.ifr_addr.sa_data[2], ifr.ifr_addr.sa_data[3]);
strcpy(ifr.ifr_name, ifname);
if (ioctl(skfd, SIOCGIFHWADDR, &ifr) < 0)
return -1;
{
/* Gotta convert from 'char' to unsigned for printf(). */
unsigned char *hwaddr = (unsigned char *)ifr.ifr_hwaddr.sa_data;
printf("The result of SIOCGIFHWADDR is type %d "
"%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x.\n",
ifr.ifr_hwaddr.sa_family, hwaddr[0], hwaddr[1],
hwaddr[2], hwaddr[3], hwaddr[4], hwaddr[5]);
}
strcpy(ifr.ifr_name, ifname);
if (ioctl(skfd, SIOCGIFMETRIC, &ifr) < 0) {
metric = 0;
} else
metric = ifr.ifr_metric;
strcpy(ifr.ifr_name, ifname);
if (ioctl(skfd, SIOCGIFMTU, &ifr) < 0)
mtu = 0;
else
mtu = ifr.ifr_mtu;
strcpy(ifr.ifr_name, ifname);
if (ioctl(skfd, SIOCGIFDSTADDR, &ifr) < 0) {
memset(&dstaddr, 0, sizeof(struct sockaddr));
} else
dstaddr = ifr.ifr_dstaddr;
strcpy(ifr.ifr_name, ifname);
if (ioctl(skfd, SIOCGIFBRDADDR, &ifr) < 0) {
memset(&broadaddr, 0, sizeof(struct sockaddr));
} else
broadaddr = ifr.ifr_broadaddr;
strcpy(ifr.ifr_name, ifname);
if (ioctl(skfd, SIOCGIFNETMASK, &ifr) < 0) {
memset(&netmask, 0, sizeof(struct sockaddr));
} else
netmask = ifr.ifr_netmask;
return(0);
}
static void if_print(char *ifname)
{
char buff[1024];
struct ifconf ifc;
struct ifreq *ifr;
int i;
if (ifname == (char *)NULL) {
ifc.ifc_len = sizeof(buff);
ifc.ifc_buf = buff;
if (ioctl(skfd, SIOCGIFCONF, &ifc) < 0) {
fprintf(stderr, "SIOCGIFCONF: %s\n", strerror(errno));
return;
}
ifr = ifc.ifc_req;
for (i = ifc.ifc_len / sizeof(struct ifreq); --i >= 0; ifr++) {
if (if_getconfig(ifr->ifr_name) < 0) {
fprintf(stderr, "%s: unknown interface.\n",
ifr->ifr_name);
continue;
}
if (((mif_flags & IFF_UP) == 0) && !opt_a) continue;
/*ife_print(&ife);*/
}
} else {
if (if_getconfig(ifname) < 0)
fprintf(stderr, "%s: unknown interface.\n", ifname);
}
}
/*
* Local variables:
* version-control: t
* kept-new-versions: 5
* c-indent-level: 4
* c-basic-offset: 4
* tab-width: 4
* compile-command: "gcc -Wall -Wstrict-prototypes -O -I/usr/src/linux/include ifenslave.c -o ifenslave"
* End:
*/
