贴一下ifconfig的源码（它属于net-tool软件包），以备平时查看网络信息的配置。
/*
* ifconfig This file contains an implementation of the command
* that either displays or sets the characteristics of
* one or more of the system's networking interfaces.
*
* Version: $Id: ifconfig.c,v 1.58 2008-10-02 23:31:04 ecki Exp $
*
* Author: Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
* and others. Copyright 1993 MicroWalt Corporation
*
* 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; either version 2 of the License, or (at
* your option) any later version.
*
* Patched to support 'add' and 'del' keywords for INET(4) addresses
* by Mrs. Brisby <mrs.brisby@nimh.org>
*
* {1.34} - 19980630 - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
* - gettext instead of catgets for i18n
* 10/1998 - Andi Kleen. Use interface list primitives.
* 20001008 - Bernd Eckenfels, Patch from RH for setting mtu
* (default AF was wrong)
* 20010404 - Arnaldo Carvalho de Melo, use setlocale
*/
#define DFLT_AF "inet"
#include "config.h"
#include <features.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <netdb.h>
/* Ugh. But libc5 doesn't provide POSIX types. */
#include <asm/types.h>
#ifdef HAVE_HWSLIP
#include <linux/if_slip.h>
#endif
#if HAVE_AFINET6
#ifndef _LINUX_IN6_H
/*
* This is in linux/include/net/ipv6.h.
*/
struct in6_ifreq {
struct in6_addr ifr6_addr;
__u32 ifr6_prefixlen;
unsigned int ifr6_ifindex;
};
#endif
#endif /* HAVE_AFINET6 */
#if HAVE_AFIPX
#if (__GLIBC__ > 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1)
#include <netipx/ipx.h>
#else
#include "ipx.h"
#endif
#endif
#include "net-support.h"
#include "pathnames.h"
#include "version.h"
#include "../intl.h"
#include "interface.h"
#include "sockets.h"
#include "util.h"
char *Release = RELEASE, *Version = "ifconfig 1.42 (2001-04-13)";
int opt_a = 0; /* show all interfaces */
int opt_v = 0; /* debugging output flag */
int addr_family = 0; /* currently selected AF */
/* for ipv4 add/del modes */
static int get_nmbc_parent(char *parent, unsigned long *nm,
unsigned long *bc);
static int set_ifstate(char *parent, unsigned long ip,
unsigned long nm, unsigned long bc,
int flag);
static int if_print(char *ifname)
{
int res;
if (ife_short)
printf(_("Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg
"));
if (!ifname) {
res = for_all_interfaces(do_if_print, &opt_a);
} else {
struct interface *ife;
ife = lookup_interface(ifname);
if (!ife) {
return -1;
}
res = do_if_fetch(ife);
if (res >= 0)
ife_print(ife);
}
return res;
}
/* Set a certain interface flag. */
static int set_flag(char *ifname, short flag)
{
struct ifreq ifr;
safe_strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
if (ioctl(skfd, SIOCGIFFLAGS, &ifr) < 0) {
fprintf(stderr, _("%s: ERROR while getting interface flags: %s
"),
ifname, strerror(errno));
return (-1);
}
safe_strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
ifr.ifr_flags |= flag;
if (ioctl(skfd, SIOCSIFFLAGS, &ifr) < 0) {
perror("SIOCSIFFLAGS");
return -1;
}
return (0);
}
/* Clear a certain interface flag. */
static int clr_flag(char *ifname, short flag)
{
struct ifreq ifr;
int fd;
if (strchr(ifname, ':')) {
/* This is a v4 alias interface. Downing it via a socket for
another AF may have bad consequences. */
fd = get_socket_for_af(AF_INET);
if (fd < 0) {
fprintf(stderr, _("No support for INET on this system.
"));
return -1;
}
} else
fd = skfd;
safe_strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
if (ioctl(fd, SIOCGIFFLAGS, &ifr) < 0) {
fprintf(stderr, _("%s: ERROR while getting interface flags: %s
"),
ifname, strerror(errno));
return -1;
}
safe_strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
ifr.ifr_flags &= ~flag;
if (ioctl(fd, SIOCSIFFLAGS, &ifr) < 0) {
perror("SIOCSIFFLAGS");
return -1;
}
return (0);
}
/** test is a specified flag is set */
static int test_flag(char *ifname, short flags)
{
struct ifreq ifr;
int fd;
if (strchr(ifname, ':')) {
/* This is a v4 alias interface. Downing it via a socket for
another AF may have bad consequences. */
fd = get_socket_for_af(AF_INET);
if (fd < 0) {
fprintf(stderr, _("No support for INET on this system.
"));
return -1;
}
} else
fd = skfd;
safe_strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
if (ioctl(fd, SIOCGIFFLAGS, &ifr) < 0) {
fprintf(stderr, _("%s: ERROR while testing interface flags: %s
"),
ifname, strerror(errno));
return -1;
}
return (ifr.ifr_flags & flags);
}
static void usage(void)
{
fprintf(stderr, _("Usage:
ifconfig [-a] [-v] [-s] <interface> [[<AF>] <address>]
"));
#if HAVE_AFINET
fprintf(stderr, _(" [add <address>[/<prefixlen>]]
"));
fprintf(stderr, _(" [del <address>[/<prefixlen>]]
"));
fprintf(stderr, _(" [[-]broadcast [<address>]] [[-]pointopoint [<address>]]
"));
fprintf(stderr, _(" [netmask <address>] [dstaddr <address>] [tunnel <address>]
"));
#endif
#ifdef SIOCSKEEPALIVE
fprintf(stderr, _(" [outfill <NN>] [keepalive <NN>]
"));
#endif
fprintf(stderr, _(" [hw <HW> <address>] [metric <NN>] [mtu <NN>]
"));
fprintf(stderr, _(" [[-]trailers] [[-]arp] [[-]allmulti]
"));
fprintf(stderr, _(" [multicast] [[-]promisc]
"));
fprintf(stderr, _(" [mem_start <NN>] [io_addr <NN>] [irq <NN>] [media <type>]
"));
#ifdef HAVE_TXQUEUELEN
fprintf(stderr, _(" [txqueuelen <NN>]
"));
#endif
#ifdef HAVE_DYNAMIC
fprintf(stderr, _(" [[-]dynamic]
"));
#endif
fprintf(stderr, _(" [up|down] ...
"));
fprintf(stderr, _(" <HW>=Hardware Type.
"));
fprintf(stderr, _(" List of possible hardware types:
"));
print_hwlist(0); /* 1 = ARPable */
fprintf(stderr, _(" <AF>=Address family. Default: %s
"), DFLT_AF);
fprintf(stderr, _(" List of possible address families:
"));
print_aflist(0); /* 1 = routeable */
exit(E_USAGE);
}
static void version(void)
{
fprintf(stderr, "%s
%s
", Release, Version);
exit(E_USAGE);
}
static int set_netmask(int skfd, struct ifreq *ifr, struct sockaddr *sa)
{
int err = 0;
memcpy((char *) &ifr->ifr_netmask, (char *) sa,
sizeof(struct sockaddr));
if (ioctl(skfd, SIOCSIFNETMASK, ifr) < 0) {
fprintf(stderr, "SIOCSIFNETMASK: %s
",
strerror(errno));
err = 1;
}
return err;
}
int main(int argc, char **argv)
{
struct sockaddr sa;
struct sockaddr samask;
struct sockaddr_in sin;
char host[128];
struct aftype *ap;
struct hwtype *hw;
struct ifreq ifr;
int goterr = 0, didnetmask = 0, neednetmask=0;
char **spp;
int fd;
#if HAVE_AFINET6
extern struct aftype inet6_aftype;
struct sockaddr_in6 sa6;
struct in6_ifreq ifr6;
unsigned long prefix_len;
char *cp;
#endif
#if HAVE_AFINET
extern struct aftype inet_aftype;
#endif
#if I18N
setlocale (LC_ALL, "");
bindtextdomain("net-tools", "/usr/share/locale");
textdomain("net-tools");
#endif
/* Find any options. */
argc--;
argv++;
while (argc && *argv[0] == '-') {
if (!strcmp(*argv, "-a"))
opt_a = 1;
else if (!strcmp(*argv, "-s"))
ife_short = 1;
else if (!strcmp(*argv, "-v"))
opt_v = 1;
else if (!strcmp(*argv, "-V") || !strcmp(*argv, "-version") ||
!strcmp(*argv, "--version"))
version();
else if (!strcmp(*argv, "-?") || !strcmp(*argv, "-h") ||
!strcmp(*argv, "-help") || !strcmp(*argv, "--help"))
usage();
else {
fprintf(stderr, _("ifconfig: option `%s' not recognised.
"),
argv[0]);
fprintf(stderr, _("ifconfig: `--help' gives usage information.
"));
exit(1);
}
argv++;
argc--;
}
/* Create a channel to the NET kernel. */
if ((skfd = sockets_open(0)) < 0) {
perror("socket");
exit(1);
}
/* Do we have to show the current setup? */
if (argc == 0) {
int err = if_print((char *) NULL);
(void) close(skfd);
exit(err < 0);
}
/* No. Fetch the interface name. */
spp = argv;
safe_strncpy(ifr.ifr_name, *spp++, IFNAMSIZ);
if (*spp == (char *) NULL) {
int err = if_print(ifr.ifr_name);
(void) close(skfd);
exit(err < 0);
}
/* The next argument is either an address family name, or an option. */
if ((ap = get_aftype(*spp)) != NULL)
spp++; /* it was a AF name */
else
ap = get_aftype(DFLT_AF);
if (ap) {
addr_family = ap->af;
skfd = ap->fd;
}
/* Process the remaining arguments. */
while (*spp != (char *) NULL) {
if (!strcmp(*spp, "arp")) {
goterr |= clr_flag(ifr.ifr_name, IFF_NOARP);
spp++;
continue;
}
if (!strcmp(*spp, "-arp")) {
goterr |= set_flag(ifr.ifr_name, IFF_NOARP);
spp++;
continue;
}
#ifdef IFF_PORTSEL
if (!strcmp(*spp, "media") || !strcmp(*spp, "port")) {
if (*++spp == NULL)
usage();
if (!strcasecmp(*spp, "auto")) {
goterr |= set_flag(ifr.ifr_name, IFF_AUTOMEDIA);
} else {
int i, j, newport;
char *endp;
newport = strtol(*spp, &endp, 10);
if (*endp != 0) {
newport = -1;
for (i = 0; if_port_text[i][0] && newport == -1; i++) {
for (j = 0; if_port_text[i][j]; j++) {
if (!strcasecmp(*spp, if_port_text[i][j])) {
newport = i;
break;
}
}
}
}
spp++;
if (newport == -1) {
fprintf(stderr, _("Unknown media type.
"));
goterr = 1;
} else {
if (ioctl(skfd, SIOCGIFMAP, &ifr) < 0) {
perror("port: SIOCGIFMAP");
goterr = 1;
continue;
}
ifr.ifr_map.port = newport;
if (ioctl(skfd, SIOCSIFMAP, &ifr) < 0) {
perror("port: SIOCSIFMAP");
goterr = 1;
}
}
}
continue;
}
#endif
if (!strcmp(*spp, "trailers")) {
goterr |= clr_flag(ifr.ifr_name, IFF_NOTRAILERS);
spp++;
continue;
}
if (!strcmp(*spp, "-trailers")) {
goterr |= set_flag(ifr.ifr_name, IFF_NOTRAILERS);
spp++;
continue;
}
if (!strcmp(*spp, "promisc")) {
goterr |= set_flag(ifr.ifr_name, IFF_PROMISC);
spp++;
continue;
}
if (!strcmp(*spp, "-promisc")) {
goterr |= clr_flag(ifr.ifr_name, IFF_PROMISC);
if (test_flag(ifr.ifr_name, IFF_PROMISC) > 0)
fprintf(stderr, _("Warning: Interface %s still in promisc mode... maybe other application is running?
"), ifr.ifr_name);
spp++;
continue;
}
if (!strcmp(*spp, "multicast")) {
goterr |= set_flag(ifr.ifr_name, IFF_MULTICAST);
spp++;
continue;
}
if (!strcmp(*spp, "-multicast")) {
goterr |= clr_flag(ifr.ifr_name, IFF_MULTICAST);
if (test_flag(ifr.ifr_name, IFF_MULTICAST) > 0)
fprintf(stderr, _("Warning: Interface %s still in MULTICAST mode.
"), ifr.ifr_name);
spp++;
continue;
}
if (!strcmp(*spp, "allmulti")) {
goterr |= set_flag(ifr.ifr_name, IFF_ALLMULTI);
spp++;
continue;
}
if (!strcmp(*spp, "-allmulti")) {
goterr |= clr_flag(ifr.ifr_name, IFF_ALLMULTI);
if (test_flag(ifr.ifr_name, IFF_MULTICAST) > 0)
fprintf(stderr, _("Warning: Interface %s still in ALLMULTI mode.
"), ifr.ifr_name);
spp++;
continue;
}
if (!strcmp(*spp, "up")) {
goterr |= set_flag(ifr.ifr_name, (IFF_UP | IFF_RUNNING));
spp++;
continue;
}
if (!strcmp(*spp, "down")) {
goterr |= clr_flag(ifr.ifr_name, IFF_UP);
spp++;
continue;
}
#ifdef HAVE_DYNAMIC
if (!strcmp(*spp, "dynamic")) {
goterr |= set_flag(ifr.ifr_name, IFF_DYNAMIC);
spp++;
continue;
}
if (!strcmp(*spp, "-dynamic")) {
goterr |= clr_flag(ifr.ifr_name, IFF_DYNAMIC);
spp++;
if (test_flag(ifr.ifr_name, IFF_MULTICAST) > 0)
fprintf(stderr, _("Warning: Interface %s still in DYNAMIC mode.
"), ifr.ifr_name);
continue;
}
#endif
if (!strcmp(*spp, "metric")) {
if (*++spp == NULL)
usage();
ifr.ifr_metric = atoi(*spp);
if (ioctl(skfd, SIOCSIFMETRIC, &ifr) < 0) {
fprintf(stderr, "SIOCSIFMETRIC: %s
", strerror(errno));
goterr = 1;
}
spp++;
continue;
}
if (!strcmp(*spp, "mtu")) {
if (*++spp == NULL)
usage();
ifr.ifr_mtu = atoi(*spp);
if (ioctl(skfd, SIOCSIFMTU, &ifr) < 0) {
fprintf(stderr, "SIOCSIFMTU: %s
", strerror(errno));
goterr = 1;
}
spp++;
continue;
}
#ifdef SIOCSKEEPALIVE
if (!strcmp(*spp, "keepalive")) {
if (*++spp == NULL)
usage();
ifr.ifr_data = (caddr_t) atoi(*spp);
if (ioctl(skfd, SIOCSKEEPALIVE, &ifr) < 0) {
fprintf(stderr, "SIOCSKEEPALIVE: %s
", strerror(errno));
goterr = 1;
}
spp++;
continue;
}
#endif
#ifdef SIOCSOUTFILL
if (!strcmp(*spp, "outfill")) {
if (*++spp == NULL)
usage();
ifr.ifr_data = (caddr_t) atoi(*spp);
if (ioctl(skfd, SIOCSOUTFILL, &ifr) < 0) {
fprintf(stderr, "SIOCSOUTFILL: %s
", strerror(errno));
goterr = 1;
}
spp++;
continue;
}
#endif
if (!strcmp(*spp, "-broadcast")) {
goterr |= clr_flag(ifr.ifr_name, IFF_BROADCAST);
if (test_flag(ifr.ifr_name, IFF_MULTICAST) > 0)
fprintf(stderr, _("Warning: Interface %s still in BROADCAST mode.
"), ifr.ifr_name);
spp++;
continue;
}
if (!strcmp(*spp, "broadcast")) {
if (*++spp != NULL) {
safe_strncpy(host, *spp, (sizeof host));
if (ap->input(0, host, &sa) < 0) {
if (ap->herror)
ap->herror(host);
else
fprintf(stderr, _("ifconfig: Error resolving '%s' for broadcast
"), host);
goterr = 1;
spp++;
continue;
}
memcpy((char *) &ifr.ifr_broadaddr, (char *) &sa,
sizeof(struct sockaddr));
if (ioctl(ap->fd, SIOCSIFBRDADDR, &ifr) < 0) {
fprintf(stderr, "SIOCSIFBRDADDR: %s
",
strerror(errno));
goterr = 1;
}
spp++;
}
goterr |= set_flag(ifr.ifr_name, IFF_BROADCAST);
continue;
}
if (!strcmp(*spp, "dstaddr")) {
if (*++spp == NULL)
usage();
safe_strncpy(host, *spp, (sizeof host));
if (ap->input(0, host, &sa) < 0) {
if (ap->herror)
ap->herror(host);
else
fprintf(stderr, _("ifconfig: Error resolving '%s' for dstaddr
"), host);
goterr = 1;
spp++;
continue;
}
memcpy((char *) &ifr.ifr_dstaddr, (char *) &sa,
sizeof(struct sockaddr));
if (ioctl(ap->fd, SIOCSIFDSTADDR, &ifr) < 0) {
fprintf(stderr, "SIOCSIFDSTADDR: %s
",
strerror(errno));
goterr = 1;
}
spp++;
continue;
}
if (!strcmp(*spp, "netmask")) {
if (*++spp == NULL || didnetmask)
usage();
safe_strncpy(host, *spp, (sizeof host));
if (ap->input(0, host, &sa) < 0) {
if (ap->herror)
ap->herror(host);
else
fprintf(stderr, _("ifconfig: Error resolving '%s' for netmask
"), host);
goterr = 1;
spp++;
continue;
}
didnetmask++;
goterr |= set_netmask(ap->fd, &ifr, &sa);
spp++;
continue;
}
#ifdef HAVE_TXQUEUELEN
if (!strcmp(*spp, "txqueuelen")) {
if (*++spp == NULL)
usage();
ifr.ifr_qlen = strtoul(*spp, NULL, 0);
if (ioctl(skfd, SIOCSIFTXQLEN, &ifr) < 0) {
fprintf(stderr, "SIOCSIFTXQLEN: %s
", strerror(errno));
goterr = 1;
}
spp++;
continue;
}
#endif
if (!strcmp(*spp, "mem_start")) {
if (*++spp == NULL)
usage();
if (ioctl(skfd, SIOCGIFMAP, &ifr) < 0) {
fprintf(stderr, "mem_start: SIOCGIFMAP: %s
", strerror(errno));
spp++;
goterr = 1;
continue;
}
ifr.ifr_map.mem_start = strtoul(*spp, NULL, 0);
if (ioctl(skfd, SIOCSIFMAP, &ifr) < 0) {
fprintf(stderr, "mem_start: SIOCSIFMAP: %s
", strerror(errno));
goterr = 1;
}
spp++;
continue;
}
if (!strcmp(*spp, "io_addr")) {
if (*++spp == NULL)
usage();
if (ioctl(skfd, SIOCGIFMAP, &ifr) < 0) {
fprintf(stderr, "io_addr: SIOCGIFMAP: %s
", strerror(errno));
spp++;
goterr = 1;
continue;
}
ifr.ifr_map.base_addr = strtol(*spp, NULL, 0);
if (ioctl(skfd, SIOCSIFMAP, &ifr) < 0) {
fprintf(stderr, "io_addr: SIOCSIFMAP: %s
", strerror(errno));
goterr = 1;
}
spp++;
continue;
}
if (!strcmp(*spp, "irq")) {
if (*++spp == NULL)
usage();
if (ioctl(skfd, SIOCGIFMAP, &ifr) < 0) {
fprintf(stderr, "irq: SIOCGIFMAP: %s
", strerror(errno));
goterr = 1;
spp++;
continue;
}
ifr.ifr_map.irq = atoi(*spp);
if (ioctl(skfd, SIOCSIFMAP, &ifr) < 0) {
fprintf(stderr, "irq: SIOCSIFMAP: %s
", strerror(errno));
goterr = 1;
}
spp++;
continue;
}
if (!strcmp(*spp, "-pointopoint")) {
goterr |= clr_flag(ifr.ifr_name, IFF_POINTOPOINT);
spp++;
if (test_flag(ifr.ifr_name, IFF_MULTICAST) > 0)
fprintf(stderr, _("Warning: Interface %s still in POINTOPOINT mode.
"), ifr.ifr_name);
continue;
}
if (!strcmp(*spp, "pointopoint")) {
if (*(spp + 1) != NULL) {
spp++;
safe_strncpy(host, *spp, (sizeof host));
if (ap->input(0, host, &sa)) {
if (ap->herror)
ap->herror(host);
else
fprintf(stderr, _("ifconfig: Error resolving '%s' for pointopoint
"), host);
goterr = 1;
spp++;
continue;
}
memcpy((char *) &ifr.ifr_dstaddr, (char *) &sa,
sizeof(struct sockaddr));
if (ioctl(ap->fd, SIOCSIFDSTADDR, &ifr) < 0) {
fprintf(stderr, "SIOCSIFDSTADDR: %s
",
strerror(errno));
goterr = 1;
}
}
goterr |= set_flag(ifr.ifr_name, IFF_POINTOPOINT);
spp++;
continue;
};
if (!strcmp(*spp, "hw")) {
if (*++spp == NULL)
usage();
if ((hw = get_hwtype(*spp)) == NULL)
usage();
if (hw->input == NULL) {
fprintf(stderr, _("hw address type `%s' has no handler to set address. failed.
"), *spp);
spp+=2;
goterr = 1;
continue;
}
if (*++spp == NULL)
usage();
safe_strncpy(host, *spp, (sizeof host));
if (hw->input(host, &sa) < 0) {
fprintf(stderr, _("%s: invalid %s address.
"), host, hw->name);
goterr = 1;
spp++;
continue;
}
memcpy((char *) &ifr.ifr_hwaddr, (char *) &sa,
sizeof(struct sockaddr));
if (ioctl(skfd, SIOCSIFHWADDR, &ifr) < 0) {
if (errno == EBUSY)
fprintf(stderr, "SIOCSIFHWADDR: %s - you may need to down the interface
",
strerror(errno));
else
fprintf(stderr, "SIOCSIFHWADDR: %s
",
strerror(errno));
goterr = 1;
}
spp++;
continue;
}
#if HAVE_AFINET || HAVE_AFINET6
if (!strcmp(*spp, "add")) {
if (*++spp == NULL)
usage();
#if HAVE_AFINET6
if (strchr(*spp, ':')) {
/* INET6 */
if ((cp = strchr(*spp, '/'))) {
prefix_len = atol(cp + 1);
if ((prefix_len < 0) || (prefix_len > 128))
usage();
*cp = 0;
} else {
prefix_len = 128;
}
safe_strncpy(host, *spp, (sizeof host));
if (inet6_aftype.input(1, host,
(struct sockaddr *) &sa6) < 0) {
if (inet6_aftype.herror)
inet6_aftype.herror(host);
else
fprintf(stderr, _("ifconfig: Error resolving '%s' for add
"), host);
goterr = 1;
spp++;
continue;
}
memcpy((char *) &ifr6.ifr6_addr, (char *) &sa6.sin6_addr,
sizeof(struct in6_addr));
fd = get_socket_for_af(AF_INET6);
if (fd < 0) {
fprintf(stderr,
_("No support for INET6 on this system.
"));
goterr = 1;
spp++;
continue;
}
if (ioctl(fd, SIOGIFINDEX, &ifr) < 0) {
perror("SIOGIFINDEX");
goterr = 1;
spp++;
continue;
}
ifr6.ifr6_ifindex = ifr.ifr_ifindex;
ifr6.ifr6_prefixlen = prefix_len;
if (ioctl(fd, SIOCSIFADDR, &ifr6) < 0) {
perror("SIOCSIFADDR");
goterr = 1;
}
spp++;
continue;
}
#endif
#ifdef HAVE_AFINET
{ /* ipv4 address a.b.c.d */
unsigned long ip, nm, bc;
safe_strncpy(host, *spp, (sizeof host));
if (inet_aftype.input(0, host, (struct sockaddr *)&sin) < 0) {
ap->herror(host);
goterr = 1;
spp++;
continue;
}
fd = get_socket_for_af(AF_INET);
if (fd < 0) {
fprintf(stderr,
_("No support for INET on this system.
"));
goterr = 1;
spp++;
continue;
}
memcpy(&ip, &sin.sin_addr.s_addr, sizeof(unsigned long));
if (get_nmbc_parent(ifr.ifr_name, &nm, &bc) < 0) {
fprintf(stderr, _("Interface %s not initialized
"),
ifr.ifr_name);
goterr = 1;
spp++;
continue;
}
set_ifstate(ifr.ifr_name, ip, nm, bc, 1);
}
spp++;
continue;
#else
fprintf(stderr, _("Bad address.
"));
#endif
}
#endif
#if HAVE_AFINET || HAVE_AFINET6
if (!strcmp(*spp, "del")) {
if (*++spp == NULL)
usage();
#ifdef SIOCDIFADDR
#if HAVE_AFINET6
if (strchr(*spp, ':')) { /* INET6 */
if ((cp = strchr(*spp, '/'))) {
prefix_len = atol(cp + 1);
if ((prefix_len < 0) || (prefix_len > 128))
usage();
*cp = 0;
} else {
prefix_len = 128;
}
safe_strncpy(host, *spp, (sizeof host));
if (inet6_aftype.input(1, host,
(struct sockaddr *) &sa6) < 0) {
inet6_aftype.herror(host);
goterr = 1;
spp++;
continue;
}
memcpy((char *) &ifr6.ifr6_addr, (char *) &sa6.sin6_addr,
sizeof(struct in6_addr));
fd = get_socket_for_af(AF_INET6);
if (fd < 0) {
fprintf(stderr,
_("No support for INET6 on this system.
"));
goterr = 1;
spp++;
continue;
}
if (ioctl(fd, SIOGIFINDEX, &ifr) < 0) {
perror("SIOGIFINDEX");
goterr = 1;
spp++;
continue;
}
ifr6.ifr6_ifindex = ifr.ifr_ifindex;
ifr6.ifr6_prefixlen = prefix_len;
if (opt_v)
fprintf(stderr, "now deleting: ioctl(SIOCDIFADDR,{ifindex=%d,prefixlen=%ld})
",ifr.ifr_ifindex,prefix_len);
if (ioctl(fd, SIOCDIFADDR, &ifr6) < 0) {
fprintf(stderr, "SIOCDIFADDR: %s
",
strerror(errno));
goterr = 1;
}
spp++;
continue;
}
#endif
#ifdef HAVE_AFINET
{
/* ipv4 address a.b.c.d */
unsigned long ip, nm, bc;
safe_strncpy(host, *spp, (sizeof host));
if (inet_aftype.input(0, host, (struct sockaddr *)&sin) < 0) {
ap->herror(host);
goterr = 1;
spp++;
continue;
}
fd = get_socket_for_af(AF_INET);
if (fd < 0) {
fprintf(stderr, _("No support for INET on this system.
"));
goterr = 1;
spp++;
continue;
}
memcpy(&ip, &sin.sin_addr.s_addr, sizeof(unsigned long));
if (get_nmbc_parent(ifr.ifr_name, &nm, &bc) < 0) {
fprintf(stderr, _("Interface %s not initialized
"),
ifr.ifr_name);
goterr = 1;
spp++;
continue;
}
set_ifstate(ifr.ifr_name, ip, nm, bc, 0);
}
spp++;
continue;
#else
fprintf(stderr, _("Bad address.
"));
#endif
#else
fprintf(stderr, _("Address deletion not supported on this system.
"));
#endif
}
#endif
#if HAVE_AFINET6
if (!strcmp(*spp, "tunnel")) {
if (*++spp == NULL)
usage();
if ((cp = strchr(*spp, '/'))) {
prefix_len = atol(cp + 1);
if ((prefix_len < 0) || (prefix_len > 128))
usage();
*cp = 0;
} else {
prefix_len = 128;
}
safe_strncpy(host, *spp, (sizeof host));
if (inet6_aftype.input(1, host, (struct sockaddr *) &sa6) < 0) {
inet6_aftype.herror(host);
goterr = 1;
spp++;
continue;
}
memcpy((char *) &ifr6.ifr6_addr, (char *) &sa6.sin6_addr,
sizeof(struct in6_addr));
fd = get_socket_for_af(AF_INET6);
if (fd < 0) {
fprintf(stderr, _("No support for INET6 on this system.
"));
goterr = 1;
spp++;
continue;
}
if (ioctl(fd, SIOGIFINDEX, &ifr) < 0) {
perror("SIOGIFINDEX");
goterr = 1;
spp++;
continue;
}
ifr6.ifr6_ifindex = ifr.ifr_ifindex;
ifr6.ifr6_prefixlen = prefix_len;
if (ioctl(fd, SIOCSIFDSTADDR, &ifr6) < 0) {
fprintf(stderr, "SIOCSIFDSTADDR: %s
",
strerror(errno));
goterr = 1;
}
spp++;
continue;
}
#endif
/* If the next argument is a valid hostname, assume OK. */
safe_strncpy(host, *spp, (sizeof host));
/* FIXME: sa is too small for INET6 addresses, inet6 should use that too,
broadcast is unexpected */
if (ap->getmask) {
switch (ap->getmask(host, &samask, NULL)) {
case -1:
usage();
break;
case 1:
if (didnetmask)
usage();
// remeber to set the netmask from samask later
neednetmask = 1;
break;
}
}
if (ap->input == NULL) {
fprintf(stderr, _("ifconfig: Cannot set address for this protocol family.
"));
exit(1);
}
if (ap->input(0, host, &sa) < 0) {
if (ap->herror)
ap->herror(host);
else
fprintf(stderr,_("ifconfig: error resolving '%s' to set address for af=%s
"), host, ap->name); fprintf(stderr,
_("ifconfig: `--help' gives usage information.
")); exit(1);
}
memcpy((char *) &ifr.ifr_addr, (char *) &sa, sizeof(struct sockaddr));
{
int r = 0; /* to shut gcc up */
switch (ap->af) {
#if HAVE_AFINET
case AF_INET:
fd = get_socket_for_af(AF_INET);
if (fd < 0) {
fprintf(stderr, _("No support for INET on this system.
"));
exit(1);
}
r = ioctl(fd, SIOCSIFADDR, &ifr);
break;
#endif
#if HAVE_AFECONET
case AF_ECONET:
fd = get_socket_for_af(AF_ECONET);
if (fd < 0) {
fprintf(stderr, _("No support for ECONET on this system.
"));
exit(1);
}
r = ioctl(fd, SIOCSIFADDR, &ifr);
break;
#endif
default:
fprintf(stderr,
_("Don't know how to set addresses for family %d.
"), ap->af);
exit(1);
}
if (r < 0) {
perror("SIOCSIFADDR");
goterr = 1;
}
}
/*
* Don't do the set_flag() if the address is an alias with a - at the
* end, since it's deleted already! - Roman
*
* Should really use regex.h here, not sure though how well it'll go
* with the cross-platform support etc.
*/
{
char *ptr;
short int found_colon = 0;
for (ptr = ifr.ifr_name; *ptr; ptr++ )
if (*ptr == ':') found_colon++;
if (!(found_colon && *(ptr - 1) == '-'))
goterr |= set_flag(ifr.ifr_name, (IFF_UP | IFF_RUNNING));
}
spp++;
}
if (neednetmask) {
goterr |= set_netmask(skfd, &ifr, &samask);
didnetmask++;
}
if (opt_v && goterr)
fprintf(stderr, _("WARNING: at least one error occured. (%d)
"), goterr);
return (goterr);
}
struct ifcmd {
int flag;
unsigned long addr;
char *base;
int baselen;
};
static unsigned char searcher[256];
static int set_ip_using(const char *name, int c, unsigned long ip)
{
struct ifreq ifr;
struct sockaddr_in sin;
safe_strncpy(ifr.ifr_name, name, IFNAMSIZ);
memset(&sin, 0, sizeof(struct sockaddr));
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = ip;
memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
if (ioctl(skfd, c, &ifr) < 0)
return -1;
return 0;
}
static int do_ifcmd(struct interface *x, struct ifcmd *ptr)
{
char *z, *e;
struct sockaddr_in *sin;
int i;
if (do_if_fetch(x) < 0)
return 0;
if (strncmp(x->name, ptr->base, ptr->baselen) != 0)
return 0; /* skip */
z = strchr(x->name, ':');
if (!z || !*z)
return 0;
z++;
for (e = z; *e; e++)
if (*e == '-') /* deleted */
return 0;
i = atoi(z);
if (i < 0 || i > 255)
abort();
searcher[i] = 1;
/* copy */
sin = (struct sockaddr_in *)&x->dstaddr;
if (sin->sin_addr.s_addr != ptr->addr) {
return 0;
}
if (ptr->flag) {
/* turn UP */
if (set_flag(x->name, IFF_UP | IFF_RUNNING) == -1)
return -1;
} else {
/* turn DOWN */
if (clr_flag(x->name, IFF_UP) == -1)
return -1;
}
return 1; /* all done! */
}
static int get_nmbc_parent(char *parent,
unsigned long *nm, unsigned long *bc)
{
struct interface *i;
struct sockaddr_in *sin;
i = lookup_interface(parent);
if (!i)
return -1;
if (do_if_fetch(i) < 0)
return 0;
sin = (struct sockaddr_in *)&i->netmask;
memcpy(nm, &sin->sin_addr.s_addr, sizeof(unsigned long));
sin = (struct sockaddr_in *)&i->broadaddr;
memcpy(bc, &sin->sin_addr.s_addr, sizeof(unsigned long));
return 0;
}
static int set_ifstate(char *parent, unsigned long ip,
unsigned long nm, unsigned long bc,
int flag)
{
char buf[IFNAMSIZ];
struct ifcmd pt;
int i;
pt.base = parent;
pt.baselen = strlen(parent);
pt.addr = ip;
pt.flag = flag;
memset(searcher, 0, sizeof(searcher));
i = for_all_interfaces((int (*)(struct interface *,void *))do_ifcmd,
&pt);
if (i == -1)
return -1;
if (i == 1)
return 0;
/* add a new interface */
for (i = 0; i < 256; i++)
if (searcher[i] == 0)
break;
if (i == 256)
return -1; /* FAILURE!!! out of ip addresses */
if (snprintf(buf, IFNAMSIZ, "%s:%d", parent, i) > IFNAMSIZ)
return -1;
if (set_ip_using(buf, SIOCSIFADDR, ip) == -1)
return -1;
if (set_ip_using(buf, SIOCSIFNETMASK, nm) == -1)
return -1;
if (set_ip_using(buf, SIOCSIFBRDADDR, bc) == -1)
return -1;
if (set_flag(buf, IFF_BROADCAST) == -1)
return -1;
return 0;
}