ifconfig 源码

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, <[e-mail]> *              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 <[e-mail]> * * {1.34} - 19980630 - Arnaldo Carvalho de Melo <[e-mail]> *                     - 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\n"));    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\n"), 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.\n"));    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\n"), 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.\n"));    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\n"), ifname, strerror(errno));return -1;    }    return (ifr.ifr_flags & flags);}static void usage(void){    fprintf(stderr, _("Usage:\n  ifconfig [-a] [-v] [-s] <interface> [[<AF>] <address>]\n"));#if HAVE_AFINET    fprintf(stderr, _("  [add <address>[/<prefixlen>]]\n"));    fprintf(stderr, _("  [del <address>[/<prefixlen>]]\n"));    fprintf(stderr, _("  [[-]broadcast [<address>]]  [[-]pointopoint [<address>]]\n"));    fprintf(stderr, _("  [netmask <address>]  [dstaddr <address>]  [tunnel <address>]\n"));#endif#ifdef SIOCSKEEPALIVE    fprintf(stderr, _("  [outfill <NN>] [keepalive <NN>]\n"));#endif    fprintf(stderr, _("  [hw <HW> <address>]  [metric <NN>]  [mtu <NN>]\n"));    fprintf(stderr, _("  [[-]trailers]  [[-]arp]  [[-]allmulti]\n"));    fprintf(stderr, _("  [multicast]  [[-]promisc]\n"));    fprintf(stderr, _("  [mem_start <NN>]  [io_addr <NN>]  [irq <NN>]  [media <type>]\n"));#ifdef HAVE_TXQUEUELEN    fprintf(stderr, _("  [txqueuelen <NN>]\n"));#endif#ifdef HAVE_DYNAMIC    fprintf(stderr, _("  [[-]dynamic]\n"));#endif    fprintf(stderr, _("  [up|down] ...\n\n"));    fprintf(stderr, _("  <HW>=Hardware Type.\n"));    fprintf(stderr, _("  List of possible hardware types:\n"));    print_hwlist(0); /* 1 = ARPable */    fprintf(stderr, _("  <AF>=Address family. Default: %s\n"), DFLT_AF);    fprintf(stderr, _("  List of possible address families:\n"));    print_aflist(0); /* 1 = routeable */    exit(E_USAGE);}static void version(void){    fprintf(stderr, "%s\n%s\n", 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\n",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.\n"),     argv[0]);    fprintf(stderr, _("ifconfig: `--help' gives usage information.\n"));    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_PORTSELif (!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.\n"));    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;}#endifif (!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?\n"), 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.\n"), 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.\n"), 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_DYNAMICif (!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.\n"), ifr.ifr_name);    continue;}#endifif (!strcmp(*spp, "metric")) {    if (*++spp == NULL)usage();    ifr.ifr_metric = atoi(*spp);    if (ioctl(skfd, SIOCSIFMETRIC, &ifr) < 0) {fprintf(stderr, "SIOCSIFMETRIC: %s\n", 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\n", strerror(errno));goterr = 1;    }    spp++;    continue;}#ifdef SIOCSKEEPALIVEif (!strcmp(*spp, "keepalive")) {    if (*++spp == NULL)usage();    ifr.ifr_data = (caddr_t) atoi(*spp);    if (ioctl(skfd, SIOCSKEEPALIVE, &ifr) < 0) {fprintf(stderr, "SIOCSKEEPALIVE: %s\n", strerror(errno));goterr = 1;    }    spp++;    continue;}#endif#ifdef SIOCSOUTFILLif (!strcmp(*spp, "outfill")) {    if (*++spp == NULL)usage();    ifr.ifr_data = (caddr_t) atoi(*spp);    if (ioctl(skfd, SIOCSOUTFILL, &ifr) < 0) {fprintf(stderr, "SIOCSOUTFILL: %s\n", strerror(errno));goterr = 1;    }    spp++;    continue;}#endifif (!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.\n"), 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\n"), 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\n",    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\n"), 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\n",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\n"), host);goterr = 1;spp++;continue;    }    didnetmask++;    goterr |= set_netmask(ap->fd, &ifr, &sa);    spp++;    continue;}#ifdef HAVE_TXQUEUELENif (!strcmp(*spp, "txqueuelen")) {    if (*++spp == NULL)usage();    ifr.ifr_qlen = strtoul(*spp, NULL, 0);    if (ioctl(skfd, SIOCSIFTXQLEN, &ifr) < 0) {fprintf(stderr, "SIOCSIFTXQLEN: %s\n", strerror(errno));goterr = 1;    }    spp++;    continue;}#endifif (!strcmp(*spp, "mem_start")) {    if (*++spp == NULL)usage();    if (ioctl(skfd, SIOCGIFMAP, &ifr) < 0) {fprintf(stderr, "mem_start: SIOCGIFMAP: %s\n", 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\n", 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\n", 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\n", 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\n", strerror(errno)); goterr = 1;spp++; continue;    }    ifr.ifr_map.irq = atoi(*spp);    if (ioctl(skfd, SIOCSIFMAP, &ifr) < 0) {fprintf(stderr, "irq: SIOCSIFMAP: %s\n", 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.\n"), 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\n"), 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\n",    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.\n"), *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.\n"), 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\n",strerror(errno));elsefprintf(stderr, "SIOCSIFHWADDR: %s\n",strerror(errno));goterr = 1;    }    spp++;    continue;}#if HAVE_AFINET || HAVE_AFINET6if (!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\n"), 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.\n"));    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.\n"));    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\n"),ifr.ifr_name);goterr = 1;spp++;continue;}set_ifstate(ifr.ifr_name, ip, nm, bc, 1);    }    spp++;    continue;#else    fprintf(stderr, _("Bad address.\n"));#endif}#endif#if HAVE_AFINET || HAVE_AFINET6if (!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.\n"));    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})\n",ifr.ifr_ifindex,prefix_len);if (ioctl(fd, SIOCDIFADDR, &ifr6) < 0) {    fprintf(stderr, "SIOCDIFADDR: %s\n",    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.\n"));    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\n"),    ifr.ifr_name);    goterr = 1;    spp++;    continue;}set_ifstate(ifr.ifr_name, ip, nm, bc, 0);    }    spp++;    continue;#else    fprintf(stderr, _("Bad address.\n"));#endif#else    fprintf(stderr, _("Address deletion not supported on this system.\n"));#endif}#endif#if HAVE_AFINET6if (!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.\n"));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\n",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 laterneednetmask = 1;break;    }}if (ap->input == NULL) {   fprintf(stderr, _("ifconfig: Cannot set address for this protocol family.\n"));   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\n"), host, ap->name); fprintf(stderr,    _("ifconfig: `--help' gives usage information.\n")); 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.\n"));    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.\n"));    exit(1);}r = ioctl(fd, SIOCSIFADDR, &ifr);break;#endif    default:fprintf(stderr,_("Don't know how to set addresses for family %d.\n"), 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)\n"), 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;}