/* Mode: C;

 * ifenslave.c: Configure network interfaces for parallel routing.

 *

 *	This program controls the Linux implementation of running multiple

 *	network interfaces in parallel.

 *

 * 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.

 *

 *    - 2003/05/01 - Amir Noam <amir.noam at intel dot com>

 *       - Added ABI version control to restore compatibility between

 *         new/old ifenslave and new/old bonding.

 *       - Prevent adding an adapter that is already a slave.

 *         Fixes the problem of stalling the transmission and leaving

 *         the slave in a down state.

 *

 *    - 2003/05/01 - Shmulik Hen <shmulik.hen at intel dot com>

 *       - Prevent enslaving if the bond device is down.

 *         Fixes the problem of leaving the system in unstable state and

 *         halting when trying to remove the module.

 *       - Close socket on all abnormal exists.

 *       - Add versioning scheme that follows that of the bonding driver.

 *         current version is 1.0.0 as a base line.

 *

 *    - 2003/05/22 - Jay Vosburgh <fubar at us dot ibm dot com>

 *	 - ifenslave -c was broken; it's now fixed

 *	 - Fixed problem with routes vanishing from master during enslave

 *	   processing.

 *

 *    - 2003/05/27 - Amir Noam <amir.noam at intel dot com>

 *	 - Fix backward compatibility issues:

 *	   For drivers not using ABI versions, slave was set down while

 *	   it should be left up before enslaving.

 *	   Also, master was not set down and the default set_mac_address()

 *	   would fail and generate an error message in the system log.

 * 	 - For opt_c: slave should not be set to the master's setting

 *	   while it is running. It was already set during enslave. To

 *	   simplify things, it is now handled separately.

 *

 *    - 2003/12/01 - Shmulik Hen <shmulik.hen at intel dot com>

 *	 - Code cleanup and style changes

 *	   set version to 1.1.0

 */

#define APP_VERSION	"1.1.0"

#define APP_RELDATE	"December 1, 2003"

#define APP_NAME	"ifenslave"

static char *version =

APP_NAME ".c:v" APP_VERSION " (" APP_RELDATE ")\n"

"o Donald Becker (becker@cesdis.gsfc.nasa.gov).\n"

"o Detach support added on 2000/10/02 by Willy Tarreau (willy at meta-x.org).\n"

"o 2.4 kernel support added on 2001/02/16 by Chad N. Tindel\n"

"  (ctindel at ieee dot org).\n";

static const char *usage_msg =

"Usage: ifenslave [-f] <master-if> <slave-if> [<slave-if>...]\n"

"       ifenslave -d   <master-if> <slave-if> [<slave-if>...]\n"

"       ifenslave -c   <master-if> <slave-if>\n"

"       ifenslave --help\n";

static const char *help_msg =

"\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 [{-f|--force}] 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"

"         (except for ALB/TLB modes)\n"

"\n"

"       To set the bond device down and automatically release all the slaves :\n"

"         # ifconfig bond0 down\n"

"\n"

"       To detach a dead interface without setting the bond device down :\n"

"         # ifenslave {-d|--detach} bond0 eth0 [eth1 [eth2]...]\n"

"\n"

"       To change active slave :\n"

"         # ifenslave {-c|--change-active} bond0 eth0\n"

"\n"

"       To show master interface info\n"

"         # ifenslave bond0\n"

"\n"

"       To show all interfaces info\n"

"       # ifenslave {-a|--all-interfaces}\n"

"\n"

"       To be more verbose\n"

"       # ifenslave {-v|--verbose} ...\n"

"\n"

"       # ifenslave {-u|--usage}   Show usage\n"

"       # ifenslave {-V|--version} Show version\n"

"       # ifenslave {-h|--help}    This message\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 <net/if_arp.h>

#include <linux/if_ether.h>

#include <linux/if_bonding.h>

#include <linux/sockios.h>

typedef unsigned long long u64;	/* hack, so we may include kernel's ethtool.h */

typedef __uint32_t u32;		/* ditto */

typedef __uint16_t u16;		/* ditto */

typedef __uint8_t u8;		/* ditto */

#include <linux/ethtool.h>

struct option longopts[] = {

	/* { name  has_arg  *flag  val } */

	{"all-interfaces",	0, 0, 'a'},	/* Show all interfaces. */

	{"change-active",	0, 0, 'c'},	/* Change the active slave.  */

	{"detach",		0, 0, 'd'},	/* Detach a slave interface. */

	{"force",		0, 0, 'f'},	/* Force the operation. */

	{"help",		0, 0, 'h'},	/* Give help */

	{"usage",		0, 0, 'u'},	/* Give usage */

	{"verbose",		0, 0, 'v'},	/* Report each action taken. */

	{"version",		0, 0, 'V'},	/* Emit version information. */

	{ 0, 0, 0, 0}

};

/* Command-line flags. */

unsigned int

opt_a = 0,	/* Show-all-interfaces flag. */

opt_c = 0,	/* Change-active-slave flag. */

opt_d = 0,	/* Detach a slave interface. */

opt_f = 0,	/* Force the operation. */

opt_h = 0,	/* Help */

opt_u = 0,	/* Usage */

opt_v = 0,	/* Verbose flag. */

opt_V = 0;	/* Version */

int skfd = -1;		/* AF_INET socket for ioctl() calls.*/

int abi_ver = 0;	/* userland - kernel ABI version */

int hwaddr_set = 0;	/* Master's hwaddr is set */

int saved_errno;

struct ifreq master_mtu, master_flags, master_hwaddr;

struct ifreq slave_mtu, slave_flags, slave_hwaddr;

struct dev_ifr {

	struct ifreq *req_ifr;

	char *req_name;

	int req_type;

};

struct dev_ifr master_ifra[] = {

	{&master_mtu,     "SIOCGIFMTU",     SIOCGIFMTU},

	{&master_flags,   "SIOCGIFFLAGS",   SIOCGIFFLAGS},

	{&master_hwaddr,  "SIOCGIFHWADDR",  SIOCGIFHWADDR},

	{NULL, "", 0}

};

struct dev_ifr slave_ifra[] = {

	{&slave_mtu,     "SIOCGIFMTU",     SIOCGIFMTU},

	{&slave_flags,   "SIOCGIFFLAGS",   SIOCGIFFLAGS},

	{&slave_hwaddr,  "SIOCGIFHWADDR",  SIOCGIFHWADDR},

	{NULL, "", 0}

};

static void if_print(char *ifname);

static int get_drv_info(char *master_ifname);

static int get_if_settings(char *ifname, struct dev_ifr ifra[]);

static int get_slave_flags(char *slave_ifname);

static int set_master_hwaddr(char *master_ifname, struct sockaddr *hwaddr);

static int set_slave_hwaddr(char *slave_ifname, struct sockaddr *hwaddr);

static int set_slave_mtu(char *slave_ifname, int mtu);

static int set_if_flags(char *ifname, short flags);

static int set_if_up(char *ifname, short flags);

static int set_if_down(char *ifname, short flags);

static int clear_if_addr(char *ifname);

static int set_if_addr(char *master_ifname, char *slave_ifname);

static int change_active(char *master_ifname, char *slave_ifname);

static int enslave(char *master_ifname, char *slave_ifname);

static int release(char *master_ifname, char *slave_ifname);

#define v_print(fmt, args...)	\

	if (opt_v)		\

		fprintf(stderr, fmt, ## args )

int main(int argc, char *argv[])

{

	char **spp, *master_ifname, *slave_ifname;

	int c, i, rv;

	int res = 0;

	int exclusive = 0;

	while ((c = getopt_long(argc, argv, "acdfhuvV", longopts, 0)) != EOF) {

		switch (c) {

		case 'a': opt_a++; exclusive++; break;

		case 'c': opt_c++; exclusive++; break;

		case 'd': opt_d++; exclusive++; break;

		case 'f': opt_f++; exclusive++; break;

		case 'h': opt_h++; exclusive++; break;

		case 'u': opt_u++; exclusive++; break;

		case 'v': opt_v++; break;

		case 'V': opt_V++; exclusive++; break;

		case '?':

			fprintf(stderr, "%s", usage_msg);

			res = 2;

			goto out;

		}

	}

	/* options check */

	if (exclusive > 1) {

		fprintf(stderr, "%s", usage_msg);

		res = 2;

		goto out;

	}

	if (opt_v || opt_V) {

		printf("%s", version);

		if (opt_V) {

			res = 0;

			goto out;

		}

	}

	if (opt_u) {

		printf("%s", usage_msg);

		res = 0;

		goto out;

	}

	if (opt_h) {

		printf("%s", usage_msg);

		printf("%s", help_msg);

		res = 0;

		goto out;

	}

	/* Open a basic socket */

	if ((skfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {

		perror("socket");

		res = 1;

		goto out;

	}

	if (opt_a) {

		if (optind == argc) {

			/* No remaining args */

			/* show all interfaces */

			if_print((char *)NULL);

			goto out;

		} else {

			/* Just show usage */

			fprintf(stderr, "%s", usage_msg);

			res = 2;

			goto out;

		}

	}

	/* Copy the interface name */

	spp = argv + optind;

	master_ifname = *spp++;

	if (master_ifname == NULL) {

		fprintf(stderr, "%s", usage_msg);

		res = 2;

		goto out;

	}

	/* exchange abi version with bonding module */

	res = get_drv_info(master_ifname);

	if (res) {

		fprintf(stderr,

			"Master '%s': Error: handshake with driver failed. "

			"Aborting\n",

			master_ifname);

		goto out;

	}

	slave_ifname = *spp++;

	if (slave_ifname == NULL) {

		if (opt_d || opt_c) {

			fprintf(stderr, "%s", usage_msg);

			res = 2;

			goto out;

		}

		/* A single arg means show the

		 * configuration for this interface

		 */

		if_print(master_ifname);

		goto out;

	}

	res = get_if_settings(master_ifname, master_ifra);

	if (res) {

		/* Probably a good reason not to go on */

		fprintf(stderr,

			"Master '%s': Error: get settings failed: %s. "

			"Aborting\n",

			master_ifname, strerror(res));

		goto out;

	}

	/* check if master is indeed a master;

	 * if not then fail any operation

	 */

	if (!(master_flags.ifr_flags & IFF_MASTER)) {

		fprintf(stderr,

			"Illegal operation; the specified interface '%s' "

			"is not a master. Aborting\n",

			master_ifname);

		res = 1;

		goto out;

	}

	/* check if master is up; if not then fail any operation */

	if (!(master_flags.ifr_flags & IFF_UP)) {

		fprintf(stderr,

			"Illegal operation; the specified master interface "

			"'%s' is not up.\n",

			master_ifname);

		res = 1;

		goto out;

	}

	/* Only for enslaving */

	if (!opt_c && !opt_d) {

		sa_family_t master_family = master_hwaddr.ifr_hwaddr.sa_family;

		unsigned char *hwaddr =

			(unsigned char *)master_hwaddr.ifr_hwaddr.sa_data;

		/* The family '1' is ARPHRD_ETHER for ethernet. */

		if (master_family != 1 && !opt_f) {

			fprintf(stderr,

				"Illegal operation: 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);

			res = 1;

			goto out;

		}

		/* Check master's hw addr */

		for (i = 0; i < 6; i++) {

			if (hwaddr[i] != 0) {

				hwaddr_set = 1;

				break;

			}

		}

		if (hwaddr_set) {

			v_print("current hardware address of master '%s' "

				"is %2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x, "

				"type %d\n",

				master_ifname,

				hwaddr[0], hwaddr[1],

				hwaddr[2], hwaddr[3],

				hwaddr[4], hwaddr[5],

				master_family);

		}

	}

	/* Accepts only one slave */

	if (opt_c) {

		/* change active slave */

		res = get_slave_flags(slave_ifname);

		if (res) {

			fprintf(stderr,

				"Slave '%s': Error: get flags failed. "

				"Aborting\n",

				slave_ifname);

			goto out;

		}

		res = change_active(master_ifname, slave_ifname);

		if (res) {

			fprintf(stderr,

				"Master '%s', Slave '%s': Error: "

				"Change active failed\n",

				master_ifname, slave_ifname);

		}

	} else {

		/* Accept multiple slaves */

		do {

			if (opt_d) {

				/* detach a slave interface from the master */

				rv = get_slave_flags(slave_ifname);

				if (rv) {

					/* Can't work with this slave. */

					/* remember the error and skip it*/

					fprintf(stderr,

						"Slave '%s': Error: get flags "

						"failed. Skipping\n",

						slave_ifname);

					res = rv;

					continue;

				}

				rv = release(master_ifname, slave_ifname);

				if (rv) {

					fprintf(stderr,

						"Master '%s', Slave '%s': Error: "

						"Release failed\n",

						master_ifname, slave_ifname);

					res = rv;

				}

			} else {

				/* attach a slave interface to the master */

				rv = get_if_settings(slave_ifname, slave_ifra);

				if (rv) {

					/* Can't work with this slave. */

					/* remember the error and skip it*/

					fprintf(stderr,

						"Slave '%s': Error: get "

						"settings failed: %s. "

						"Skipping\n",

						slave_ifname, strerror(rv));

					res = rv;

					continue;

				}

				rv = enslave(master_ifname, slave_ifname);

				if (rv) {

					fprintf(stderr,

						"Master '%s', Slave '%s': Error: "

						"Enslave failed\n",

						master_ifname, slave_ifname);

					res = rv;

				}

			}

		} while ((slave_ifname = *spp++) != NULL);

	}

out:

	if (skfd >= 0) {

		close(skfd);

	}

	return res;

}

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;

	unsigned char *hwaddr;

	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[2], ifr.ifr_addr.sa_data[3],

	       ifr.ifr_addr.sa_data[4], ifr.ifr_addr.sa_data[5]);

	strcpy(ifr.ifr_name, ifname);

	if (ioctl(skfd, SIOCGIFHWADDR, &ifr) < 0)

		return -1;

	/* Gotta convert from 'char' to unsigned for printf(). */

	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;

	printf("The result of SIOCGIFMETRIC is %d\n", metric);

	strcpy(ifr.ifr_name, ifname);

	if (ioctl(skfd, SIOCGIFMTU, &ifr) < 0)

		mtu = 0;

	else

		mtu = ifr.ifr_mtu;

	printf("The result of SIOCGIFMTU is %d\n", 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) {

			perror("SIOCGIFCONF failed");

			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);

		}

	}

}

static int get_drv_info(char *master_ifname)

{

	struct ifreq ifr;

	struct ethtool_drvinfo info;

	char *endptr;

	memset(&ifr, 0, sizeof(ifr));

	strncpy(ifr.ifr_name, master_ifname, IFNAMSIZ);

	ifr.ifr_data = (caddr_t)&info;

	info.cmd = ETHTOOL_GDRVINFO;

	strncpy(info.driver, "ifenslave", 32);

	snprintf(info.fw_version, 32, "%d", BOND_ABI_VERSION);

	if (ioctl(skfd, SIOCETHTOOL, &ifr) < 0) {

		if (errno == EOPNOTSUPP) {

			goto out;

		}

		saved_errno = errno;

		v_print("Master '%s': Error: get bonding info failed %s\n",

			master_ifname, strerror(saved_errno));

		return 1;

	}

	abi_ver = strtoul(info.fw_version, &endptr, 0);

	if (*endptr) {

                v_print("Master '%s': Error: got invalid string as an ABI "

			"version from the bonding module\n",

			master_ifname);

		return 1;

	}

out:

	v_print("ABI ver is %d\n", abi_ver);

	return 0;

}

static int change_active(char *master_ifname, char *slave_ifname)

{

	struct ifreq ifr;

	int res = 0;

	if (!(slave_flags.ifr_flags & IFF_SLAVE)) {

		fprintf(stderr,

			"Illegal operation: The specified slave interface "

			"'%s' is not a slave\n",

			slave_ifname);

		return 1;

	}

	strncpy(ifr.ifr_name, master_ifname, IFNAMSIZ);

	strncpy(ifr.ifr_slave, slave_ifname, IFNAMSIZ);

	if ((ioctl(skfd, SIOCBONDCHANGEACTIVE, &ifr) < 0) &&

	    (ioctl(skfd, BOND_CHANGE_ACTIVE_OLD, &ifr) < 0)) {

		saved_errno = errno;

		v_print("Master '%s': Error: SIOCBONDCHANGEACTIVE failed: "

			"%s\n",

			master_ifname, strerror(saved_errno));

		res = 1;

	}

	return res;

}

static int enslave(char *master_ifname, char *slave_ifname)

{

	struct ifreq ifr;

	int res = 0;

	if (slave_flags.ifr_flags & IFF_SLAVE) {

		fprintf(stderr,

			"Illegal operation: The specified slave interface "

			"'%s' is already a slave\n",

			slave_ifname);

		return 1;

	}

	res = set_if_down(slave_ifname, slave_flags.ifr_flags);

	if (res) {

		fprintf(stderr,

			"Slave '%s': Error: bring interface down failed\n",

			slave_ifname);

		return res;

	}

	if (abi_ver < 2) {

		/* Older bonding versions would panic if the slave has no IP

		 * address, so get the IP setting from the master.

		 */

		set_if_addr(master_ifname, slave_ifname);

	} else {

		res = clear_if_addr(slave_ifname);

		if (res) {

			fprintf(stderr,

				"Slave '%s': Error: clear address failed\n",

				slave_ifname);

			return res;

		}

	}

	if (master_mtu.ifr_mtu != slave_mtu.ifr_mtu) {

		res = set_slave_mtu(slave_ifname, master_mtu.ifr_mtu);

		if (res) {

			fprintf(stderr,

				"Slave '%s': Error: set MTU failed\n",

				slave_ifname);

			return res;

		}

	}

	if (hwaddr_set) {

		/* Master already has an hwaddr

		 * so set it's hwaddr to the slave

		 */

		if (abi_ver < 1) {

			/* The driver is using an old ABI, so

			 * the application sets the slave's

			 * hwaddr

			 */

			res = set_slave_hwaddr(slave_ifname,

					       &(master_hwaddr.ifr_hwaddr));

			if (res) {

				fprintf(stderr,

					"Slave '%s': Error: set hw address "

					"failed\n",

					slave_ifname);

				goto undo_mtu;

			}

			/* For old ABI the application needs to bring the

			 * slave back up

			 */

			res = set_if_up(slave_ifname, slave_flags.ifr_flags);

			if (res) {

				fprintf(stderr,

					"Slave '%s': Error: bring interface "

					"down failed\n",

					slave_ifname);

				goto undo_slave_mac;

			}

		}

		/* The driver is using a new ABI,

		 * so the driver takes care of setting

		 * the slave's hwaddr and bringing

		 * it up again

		 */

	} else {

		/* No hwaddr for master yet, so

		 * set the slave's hwaddr to it

		 */

		if (abi_ver < 1) {

			/* For old ABI, the master needs to be

			 * down before setting its hwaddr

			 */

			res = set_if_down(master_ifname, master_flags.ifr_flags);

			if (res) {

				fprintf(stderr,

					"Master '%s': Error: bring interface "

					"down failed\n",

					master_ifname);

				goto undo_mtu;

			}

		}

		res = set_master_hwaddr(master_ifname,

					&(slave_hwaddr.ifr_hwaddr));

		if (res) {

			fprintf(stderr,

				"Master '%s': Error: set hw address "

				"failed\n",

				master_ifname);

			goto undo_mtu;

		}

		if (abi_ver < 1) {

			/* For old ABI, bring the master

			 * back up

			 */

			res = set_if_up(master_ifname, master_flags.ifr_flags);

			if (res) {

				fprintf(stderr,

					"Master '%s': Error: bring interface "

					"up failed\n",

					master_ifname);

				goto undo_master_mac;

			}

		}

		hwaddr_set = 1;

	}

	/* Do the real thing */

	strncpy(ifr.ifr_name, master_ifname, IFNAMSIZ);

	strncpy(ifr.ifr_slave, slave_ifname, IFNAMSIZ);

	if ((ioctl(skfd, SIOCBONDENSLAVE, &ifr) < 0) &&

	    (ioctl(skfd, BOND_ENSLAVE_OLD, &ifr) < 0)) {

		saved_errno = errno;

		v_print("Master '%s': Error: SIOCBONDENSLAVE failed: %s\n",

			master_ifname, strerror(saved_errno));

		res = 1;

	}

	if (res) {

		goto undo_master_mac;

	}

	return 0;

/* rollback (best effort) */

undo_master_mac:

	set_master_hwaddr(master_ifname, &(master_hwaddr.ifr_hwaddr));

	hwaddr_set = 0;

	goto undo_mtu;

undo_slave_mac:

	set_slave_hwaddr(slave_ifname, &(slave_hwaddr.ifr_hwaddr));

undo_mtu:

	set_slave_mtu(slave_ifname, slave_mtu.ifr_mtu);

	return res;

}

static int release(char *master_ifname, char *slave_ifname)

{

	struct ifreq ifr;

	int res = 0;

	if (!(slave_flags.ifr_flags & IFF_SLAVE)) {

		fprintf(stderr,

			"Illegal operation: The specified slave interface "

			"'%s' is not a slave\n",

			slave_ifname);

		return 1;

	}

	strncpy(ifr.ifr_name, master_ifname, IFNAMSIZ);

	strncpy(ifr.ifr_slave, slave_ifname, IFNAMSIZ);

	if ((ioctl(skfd, SIOCBONDRELEASE, &ifr) < 0) &&

	    (ioctl(skfd, BOND_RELEASE_OLD, &ifr) < 0)) {

		saved_errno = errno;

		v_print("Master '%s': Error: SIOCBONDRELEASE failed: %s\n",

			master_ifname, strerror(saved_errno));

		return 1;

	} else if (abi_ver < 1) {

		/* The driver is using an old ABI, so we'll set the interface

		 * down to avoid any conflicts due to same MAC/IP

		 */

		res = set_if_down(slave_ifname, slave_flags.ifr_flags);

		if (res) {

			fprintf(stderr,

				"Slave '%s': Error: bring interface "

				"down failed\n",

				slave_ifname);

		}

	}

	/* set to default mtu */

	set_slave_mtu(slave_ifname, 1500);

	return res;

}

static int get_if_settings(char *ifname, struct dev_ifr ifra[])

{

	int i;

	int res = 0;

	for (i = 0; ifra[i].req_ifr; i++) {

		strncpy(ifra[i].req_ifr->ifr_name, ifname, IFNAMSIZ);

		res = ioctl(skfd, ifra[i].req_type, ifra[i].req_ifr);

		if (res < 0) {

			saved_errno = errno;

			v_print("Interface '%s': Error: %s failed: %s\n",

				ifname, ifra[i].req_name,