Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1110 insertions, 0 deletions

diff --git a/Documentation/networking/ifenslave.c b/Documentation/networking/ifenslave.c
new file mode 100644
index 00000000000..f315d20d386
--- /dev/null
+++ b/Documentation/networking/ifenslave.c
@@ -0,0 +1,1110 @@
+/* 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 handeled 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, usage_msg);
+			res = 2;
+			goto out;
+		}
+	}
+
+	/* options check */
+	if (exclusive > 1) {
+		fprintf(stderr, usage_msg);
+		res = 2;
+		goto out;
+	}
+
+	if (opt_v || opt_V) {
+		printf(version);
+		if (opt_V) {
+			res = 0;
+			goto out;
+		}
+	}
+
+	if (opt_u) {
+		printf(usage_msg);
+		res = 0;
+		goto out;
+	}
+
+	if (opt_h) {
+		printf(usage_msg);
+		printf(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, usage_msg);
+			res = 2;
+			goto out;
+		}
+	}
+
+	/* Copy the interface name */
+	spp = argv + optind;
+	master_ifname = *spp++;
+
+	if (master_ifname == NULL) {
+		fprintf(stderr, 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, 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[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(). */
+	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) {
+			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.
+		 */
+		res = set_if_addr(master_ifname, slave_ifname);
+		if (res) {
+			fprintf(stderr,
+				"Slave '%s': Error: set address failed\n",
+				slave_ifname);
+			return res;
+		}
+	} 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 it's 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,
+				strerror(saved_errno));
+
+			return saved_errno;
+		}
+	}
+
+	return 0;
+}
+
+static int get_slave_flags(char *slave_ifname)
+{
+	int res = 0;
+
+	strncpy(slave_flags.ifr_name, slave_ifname, IFNAMSIZ);
+	res = ioctl(skfd, SIOCGIFFLAGS, &slave_flags);
+	if (res < 0) {
+		saved_errno = errno;
+		v_print("Slave '%s': Error: SIOCGIFFLAGS failed: %s\n",
+			slave_ifname, strerror(saved_errno));
+	} else {
+		v_print("Slave %s: flags %04X.\n",
+			slave_ifname, slave_flags.ifr_flags);
+	}
+
+	return res;
+}
+
+static int set_master_hwaddr(char *master_ifname, struct sockaddr *hwaddr)
+{
+	unsigned char *addr = (unsigned char *)hwaddr->sa_data;
+	struct ifreq ifr;
+	int res = 0;
+
+	strncpy(ifr.ifr_name, master_ifname, IFNAMSIZ);
+	memcpy(&(ifr.ifr_hwaddr), hwaddr, sizeof(struct sockaddr));
+	res = ioctl(skfd, SIOCSIFHWADDR, &ifr);
+	if (res < 0) {
+		saved_errno = errno;
+		v_print("Master '%s': Error: SIOCSIFHWADDR failed: %s\n",
+			master_ifname, strerror(saved_errno));
+		return res;
+	} else {
+		v_print("Master '%s': hardware address set to "
+			"%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x.\n",
+			master_ifname, addr[0], addr[1], addr[2],
+			addr[3], addr[4], addr[5]);
+	}
+
+	return res;
+}
+
+static int set_slave_hwaddr(char *slave_ifname, struct sockaddr *hwaddr)
+{
+	unsigned char *addr = (unsigned char *)hwaddr->sa_data;
+	struct ifreq ifr;
+	int res = 0;
+
+	strncpy(ifr.ifr_name, slave_ifname, IFNAMSIZ);
+	memcpy(&(ifr.ifr_hwaddr), hwaddr, sizeof(struct sockaddr));
+	res = ioctl(skfd, SIOCSIFHWADDR, &ifr);
+	if (res < 0) {
+		saved_errno = errno;
+
+		v_print("Slave '%s': Error: SIOCSIFHWADDR failed: %s\n",
+			slave_ifname, strerror(saved_errno));
+
+		if (saved_errno == EBUSY) {
+			v_print("  The device is busy: it must be idle "
+				"before running this command.\n");
+		} else if (saved_errno == EOPNOTSUPP) {
+			v_print("  The device does not support setting "
+				"the MAC address.\n"
+				"  Your kernel likely does not support slave "
+				"devices.\n");
+		} else if (saved_errno == EINVAL) {
+			v_print("  The device's address type does not match "
+				"the master's address type.\n");
+		}
+		return res;
+	} else {
+		v_print("Slave '%s': hardware address set to "
+			"%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x.\n",
+			slave_ifname, addr[0], addr[1], addr[2],
+			addr[3], addr[4], addr[5]);
+	}
+
+	return res;
+}
+
+static int set_slave_mtu(char *slave_ifname, int mtu)
+{
+	struct ifreq ifr;
+	int res = 0;
+
+	ifr.ifr_mtu = mtu;
+	strncpy(ifr.ifr_name, slave_ifname, IFNAMSIZ);
+
+	res = ioctl(skfd, SIOCSIFMTU, &ifr);
+	if (res < 0) {
+		saved_errno = errno;
+		v_print("Slave '%s': Error: SIOCSIFMTU failed: %s\n",
+			slave_ifname, strerror(saved_errno));
+	} else {
+		v_print("Slave '%s': MTU set to %d.\n", slave_ifname, mtu);
+	}
+
+	return res;
+}
+
+static int set_if_flags(char *ifname, short flags)
+{
+	struct ifreq ifr;
+	int res = 0;
+
+	ifr.ifr_flags = flags;
+	strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
+
+	res = ioctl(skfd, SIOCSIFFLAGS, &ifr);
+	if (res < 0) {
+		saved_errno = errno;
+		v_print("Interface '%s': Error: SIOCSIFFLAGS failed: %s\n",
+			ifname, strerror(saved_errno));
+	} else {
+		v_print("Interface '%s': flags set to %04X.\n", ifname, flags);
+	}
+
+	return res;
+}
+
+static int set_if_up(char *ifname, short flags)
+{
+	return set_if_flags(ifname, flags | IFF_UP);
+}
+
+static int set_if_down(char *ifname, short flags)
+{
+	return set_if_flags(ifname, flags & ~IFF_UP);
+}
+
+static int clear_if_addr(char *ifname)
+{
+	struct ifreq ifr;
+	int res = 0;
+
+	strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
+	ifr.ifr_addr.sa_family = AF_INET;
+	memset(ifr.ifr_addr.sa_data, 0, sizeof(ifr.ifr_addr.sa_data));
+
+	res = ioctl(skfd, SIOCSIFADDR, &ifr);
+	if (res < 0) {
+		saved_errno = errno;
+		v_print("Interface '%s': Error: SIOCSIFADDR failed: %s\n",
+			ifname, strerror(saved_errno));
+	} else {
+		v_print("Interface '%s': address cleared\n", ifname);
+	}
+
+	return res;
+}
+
+static int set_if_addr(char *master_ifname, char *slave_ifname)
+{
+	struct ifreq ifr;
+	int res;
+	unsigned char *ipaddr;
+	int i;
+	struct {
+		char *req_name;
+		char *desc;
+		int g_ioctl;
+		int s_ioctl;
+	} ifra[] = {
+		{"IFADDR", "addr", SIOCGIFADDR, SIOCSIFADDR},
+		{"DSTADDR", "destination addr", SIOCGIFDSTADDR, SIOCSIFDSTADDR},
+		{"BRDADDR", "broadcast addr", SIOCGIFBRDADDR, SIOCSIFBRDADDR},
+		{"NETMASK", "netmask", SIOCGIFNETMASK, SIOCSIFNETMASK},
+		{NULL, NULL, 0, 0},
+	};
+
+	for (i = 0; ifra[i].req_name; i++) {
+		strncpy(ifr.ifr_name, master_ifname, IFNAMSIZ);
+		res = ioctl(skfd, ifra[i].g_ioctl, &ifr);
+		if (res < 0) {
+			int saved_errno = errno;
+
+			v_print("Interface '%s': Error: SIOCG%s failed: %s\n",
+				master_ifname, ifra[i].req_name,
+				strerror(saved_errno));
+
+			ifr.ifr_addr.sa_family = AF_INET;
+			memset(ifr.ifr_addr.sa_data, 0,
+			       sizeof(ifr.ifr_addr.sa_data));
+		}
+
+		strncpy(ifr.ifr_name, slave_ifname, IFNAMSIZ);
+		res = ioctl(skfd, ifra[i].s_ioctl, &ifr);
+		if (res < 0) {
+			int saved_errno = errno;
+
+			v_print("Interface '%s': Error: SIOCS%s failed: %s\n",
+				slave_ifname, ifra[i].req_name,
+				strerror(saved_errno));
+
+			return res;
+		}
+
+		ipaddr = ifr.ifr_addr.sa_data;
+		v_print("Interface '%s': set IP %s to %d.%d.%d.%d\n",
+			slave_ifname, ifra[i].desc,
+			ipaddr[0], ipaddr[1], ipaddr[2], ipaddr[3]);
+	}
+
+	return 0;
+}
+
+/*
+ * 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:
+ */
+