networking/ifconfig.c

   1 /* ifconfig
   2  *
   3  * Similar to the standard Unix ifconfig, but with only the necessary
   4  * parts for AF_INET, and without any printing of if info (for now).
   5  *
   6  * Bjorn Wesen, Axis Communications AB
   7  *
   8  *
   9  * Authors of the original ifconfig was:
  10  *              Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
  11  *
  12  * This program is free software; you can redistribute it
  13  * and/or  modify it under  the terms of  the GNU General
  14  * Public  License as  published  by  the  Free  Software
  15  * Foundation;  either  version 2 of the License, or  (at
  16  * your option) any later version.
  17  *
  18  * $Id: ifconfig.c,v 1.30 2004/03/31 11:30:08 andersen Exp $
  19  *
  20  */
  21
  22 /*
  23  * Heavily modified by Manuel Novoa III       Mar 6, 2001
  24  *
  25  * From initial port to busybox, removed most of the redundancy by
  26  * converting to a table-driven approach.  Added several (optional)
  27  * args missing from initial port.
  28  *
  29  * Still missing:  media, tunnel.
  30  *
  31  * 2002-04-20
  32  * IPV6 support added by Bart Visscher <magick@linux-fan.com>
  33  */
  34
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>             /* strcmp and friends */
  38 #include <ctype.h>              /* isdigit and friends */
  39 #include <stddef.h>             /* offsetof */
  40 #include <netdb.h>
  41 #include <sys/ioctl.h>
  42 #include <net/if.h>
  43 #include <net/if_arp.h>
  44 #include <netinet/in.h>
  45 #if __GLIBC__ >=2 && __GLIBC_MINOR >= 1
  46 #include <netpacket/packet.h>
  47 #include <net/ethernet.h>
  48 #else
  49 #include <asm/types.h>
  50 #include <linux/if_ether.h>
  51 #endif
  52 #include "inet_common.h"
  53 #include "busybox.h"
  54
  55 #ifdef CONFIG_FEATURE_IFCONFIG_SLIP
  56 # include <net/if_slip.h>
  57 #endif
  58
  59 /* I don't know if this is needed for busybox or not.  Anyone? */
  60 #define QUESTIONABLE_ALIAS_CASE
  61
  62
  63 /* Defines for glibc2.0 users. */
  64 #ifndef SIOCSIFTXQLEN
  65 # define SIOCSIFTXQLEN      0x8943
  66 # define SIOCGIFTXQLEN      0x8942
  67 #endif
  68
  69 /* ifr_qlen is ifru_ivalue, but it isn't present in 2.0 kernel headers */
  70 #ifndef ifr_qlen
  71 # define ifr_qlen        ifr_ifru.ifru_mtu
  72 #endif
  73
  74 #ifndef IFF_DYNAMIC
  75 # define IFF_DYNAMIC     0x8000 /* dialup device with changing addresses */
  76 #endif
  77
  78 #ifdef CONFIG_FEATURE_IPV6
  79 struct in6_ifreq {
  80         struct in6_addr ifr6_addr;
  81         uint32_t ifr6_prefixlen;
  82         int ifr6_ifindex;
  83 };
  84 #endif
  85
  86 /*
  87  * Here are the bit masks for the "flags" member of struct options below.
  88  * N_ signifies no arg prefix; M_ signifies arg prefixed by '-'.
  89  * CLR clears the flag; SET sets the flag; ARG signifies (optional) arg.
  90  */
  91 #define N_CLR            0x01
  92 #define M_CLR            0x02
  93 #define N_SET            0x04
  94 #define M_SET            0x08
  95 #define N_ARG            0x10
  96 #define M_ARG            0x20
  97
  98 #define M_MASK           (M_CLR | M_SET | M_ARG)
  99 #define N_MASK           (N_CLR | N_SET | N_ARG)
 100 #define SET_MASK         (N_SET | M_SET)
 101 #define CLR_MASK         (N_CLR | M_CLR)
 102 #define SET_CLR_MASK     (SET_MASK | CLR_MASK)
 103 #define ARG_MASK         (M_ARG | N_ARG)
 104
 105 /*
 106  * Here are the bit masks for the "arg_flags" member of struct options below.
 107  */
 108
 109 /*
 110  * cast type:
 111  *   00 int
 112  *   01 char *
 113  *   02 HOST_COPY in_ether
 114  *   03 HOST_COPY INET_resolve
 115  */
 116 #define A_CAST_TYPE      0x03
 117 /*
 118  * map type:
 119  *   00 not a map type (mem_start, io_addr, irq)
 120  *   04 memstart (unsigned long)
 121  *   08 io_addr  (unsigned short)
 122  *   0C irq      (unsigned char)
 123  */
 124 #define A_MAP_TYPE       0x0C
 125 #define A_ARG_REQ        0x10   /* Set if an arg is required. */
 126 #define A_NETMASK        0x20   /* Set if netmask (check for multiple sets). */
 127 #define A_SET_AFTER      0x40   /* Set a flag at the end. */
 128 #define A_COLON_CHK      0x80   /* Is this needed?  See below. */
 129 #ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 130 #define A_HOSTNAME      0x100   /* Set if it is ip addr. */
 131 #define A_BROADCAST     0x200   /* Set if it is broadcast addr. */
 132 #else
 133 #define A_HOSTNAME          0
 134 #define A_BROADCAST         0
 135 #endif
 136
 137 /*
 138  * These defines are for dealing with the A_CAST_TYPE field.
 139  */
 140 #define A_CAST_CHAR_PTR  0x01
 141 #define A_CAST_RESOLVE   0x01
 142 #define A_CAST_HOST_COPY 0x02
 143 #define A_CAST_HOST_COPY_IN_ETHER    A_CAST_HOST_COPY
 144 #define A_CAST_HOST_COPY_RESOLVE     (A_CAST_HOST_COPY | A_CAST_RESOLVE)
 145
 146 /*
 147  * These defines are for dealing with the A_MAP_TYPE field.
 148  */
 149 #define A_MAP_ULONG      0x04   /* memstart */
 150 #define A_MAP_USHORT     0x08   /* io_addr */
 151 #define A_MAP_UCHAR      0x0C   /* irq */
 152
 153 /*
 154  * Define the bit masks signifying which operations to perform for each arg.
 155  */
 156
 157 #define ARG_METRIC       (A_ARG_REQ /*| A_CAST_INT*/)
 158 #define ARG_MTU          (A_ARG_REQ /*| A_CAST_INT*/)
 159 #define ARG_TXQUEUELEN   (A_ARG_REQ /*| A_CAST_INT*/)
 160 #define ARG_MEM_START    (A_ARG_REQ | A_MAP_ULONG)
 161 #define ARG_IO_ADDR      (A_ARG_REQ | A_MAP_ULONG)
 162 #define ARG_IRQ          (A_ARG_REQ | A_MAP_UCHAR)
 163 #define ARG_DSTADDR      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE)
 164 #define ARG_NETMASK      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_NETMASK)
 165 #define ARG_BROADCAST    (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_BROADCAST)
 166 #define ARG_HW           (A_ARG_REQ | A_CAST_HOST_COPY_IN_ETHER)
 167 #define ARG_POINTOPOINT  (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER)
 168 #define ARG_KEEPALIVE    (A_ARG_REQ | A_CAST_CHAR_PTR)
 169 #define ARG_OUTFILL      (A_ARG_REQ | A_CAST_CHAR_PTR)
 170 #define ARG_HOSTNAME     (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_COLON_CHK | A_HOSTNAME)
 171 #define ARG_ADD_DEL      (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER)
 172
 173
 174 /*
 175  * Set up the tables.  Warning!  They must have corresponding order!
 176  */
 177
 178 struct arg1opt {
 179         const char *name;
 180         unsigned short selector;
 181         unsigned short ifr_offset;
 182 };
 183
 184 struct options {
 185         const char *name;
 186 #ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 187         const unsigned int flags:6;
 188         const unsigned int arg_flags:10;
 189 #else
 190         const unsigned char flags;
 191         const unsigned char arg_flags;
 192 #endif
 193         const unsigned short selector;
 194 };
 195
 196 #define ifreq_offsetof(x)  offsetof(struct ifreq, x)
 197
 198 static const struct arg1opt Arg1Opt[] = {
 199         {"SIOCSIFMETRIC",  SIOCSIFMETRIC,  ifreq_offsetof(ifr_metric)},
 200         {"SIOCSIFMTU",     SIOCSIFMTU,     ifreq_offsetof(ifr_mtu)},
 201         {"SIOCSIFTXQLEN",  SIOCSIFTXQLEN,  ifreq_offsetof(ifr_qlen)},
 202         {"SIOCSIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr)},
 203         {"SIOCSIFNETMASK", SIOCSIFNETMASK, ifreq_offsetof(ifr_netmask)},
 204         {"SIOCSIFBRDADDR", SIOCSIFBRDADDR, ifreq_offsetof(ifr_broadaddr)},
 205 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 206         {"SIOCSIFHWADDR",  SIOCSIFHWADDR,  ifreq_offsetof(ifr_hwaddr)},
 207 #endif
 208         {"SIOCSIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr)},
 209 #ifdef SIOCSKEEPALIVE
 210         {"SIOCSKEEPALIVE", SIOCSKEEPALIVE, ifreq_offsetof(ifr_data)},
 211 #endif
 212 #ifdef SIOCSOUTFILL
 213         {"SIOCSOUTFILL",   SIOCSOUTFILL,   ifreq_offsetof(ifr_data)},
 214 #endif
 215 #ifdef CONFIG_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 216         {"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.mem_start)},
 217         {"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.base_addr)},
 218         {"SIOCSIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.irq)},
 219 #endif
 220         /* Last entry if for unmatched (possibly hostname) arg. */
 221 #ifdef CONFIG_FEATURE_IPV6
 222         {"SIOCSIFADDR",    SIOCSIFADDR,    ifreq_offsetof(ifr_addr)}, /* IPv6 version ignores the offset */
 223         {"SIOCDIFADDR",    SIOCDIFADDR,    ifreq_offsetof(ifr_addr)}, /* IPv6 version ignores the offset */
 224 #endif
 225         {"SIOCSIFADDR",    SIOCSIFADDR,    ifreq_offsetof(ifr_addr)},
 226 };
 227
 228 static const struct options OptArray[] = {
 229         {"metric",      N_ARG,         ARG_METRIC,      0},
 230         {"mtu",         N_ARG,         ARG_MTU,         0},
 231         {"txqueuelen",  N_ARG,         ARG_TXQUEUELEN,  0},
 232         {"dstaddr",     N_ARG,         ARG_DSTADDR,     0},
 233         {"netmask",     N_ARG,         ARG_NETMASK,     0},
 234         {"broadcast",   N_ARG | M_CLR, ARG_BROADCAST,   IFF_BROADCAST},
 235 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 236         {"hw",          N_ARG, ARG_HW,                  0},
 237 #endif
 238         {"pointopoint", N_ARG | M_CLR, ARG_POINTOPOINT, IFF_POINTOPOINT},
 239 #ifdef SIOCSKEEPALIVE
 240         {"keepalive",   N_ARG,         ARG_KEEPALIVE,   0},
 241 #endif
 242 #ifdef SIOCSOUTFILL
 243         {"outfill",     N_ARG,         ARG_OUTFILL,     0},
 244 #endif
 245 #ifdef CONFIG_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 246         {"mem_start",   N_ARG,         ARG_MEM_START,   0},
 247         {"io_addr",     N_ARG,         ARG_IO_ADDR,     0},
 248         {"irq",         N_ARG,         ARG_IRQ,         0},
 249 #endif
 250 #ifdef CONFIG_FEATURE_IPV6
 251         {"add",         N_ARG,         ARG_ADD_DEL,     0},
 252         {"del",         N_ARG,         ARG_ADD_DEL,     0},
 253 #endif
 254         {"arp",         N_CLR | M_SET, 0,               IFF_NOARP},
 255         {"trailers",    N_CLR | M_SET, 0,               IFF_NOTRAILERS},
 256         {"promisc",     N_SET | M_CLR, 0,               IFF_PROMISC},
 257         {"multicast",   N_SET | M_CLR, 0,               IFF_MULTICAST},
 258         {"allmulti",    N_SET | M_CLR, 0,               IFF_ALLMULTI},
 259         {"dynamic",     N_SET | M_CLR, 0,               IFF_DYNAMIC},
 260         {"up",          N_SET,         0,               (IFF_UP | IFF_RUNNING)},
 261         {"down",        N_CLR,         0,               IFF_UP},
 262         {NULL,          0,             ARG_HOSTNAME,    (IFF_UP | IFF_RUNNING)}
 263 };
 264
 265 /*
 266  * A couple of prototypes.
 267  */
 268
 269 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 270 static int in_ether(char *bufp, struct sockaddr *sap);
 271 #endif
 272
 273 #ifdef CONFIG_FEATURE_IFCONFIG_STATUS
 274 extern int interface_opt_a;
 275 extern int display_interfaces(char *ifname);
 276 #endif
 277
 278 /*
 279  * Our main function.
 280  */
 281
 282 int ifconfig_main(int argc, char **argv)
 283 {
 284         struct ifreq ifr;
 285         struct sockaddr_in sai;
 286 #ifdef CONFIG_FEATURE_IPV6
 287         struct sockaddr_in6 sai6;
 288 #endif
 289 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 290         struct sockaddr sa;
 291 #endif
 292         const struct arg1opt *a1op;
 293         const struct options *op;
 294         int sockfd;                     /* socket fd we use to manipulate stuff with */
 295         int goterr;
 296         int selector;
 297 #ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 298         unsigned int mask;
 299         unsigned int did_flags;
 300         unsigned int sai_hostname, sai_netmask;
 301 #else
 302         unsigned char mask;
 303         unsigned char did_flags;
 304 #endif
 305         char *p;
 306         char host[128];
 307
 308         goterr = 0;
 309         did_flags = 0;
 310 #ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 311         sai_hostname = 0;
 312         sai_netmask = 0;
 313 #endif
 314
 315         /* skip argv[0] */
 316         ++argv;
 317         --argc;
 318
 319 #ifdef CONFIG_FEATURE_IFCONFIG_STATUS
 320         if ((argc > 0) && (((*argv)[0] == '-') && ((*argv)[1] == 'a') && !(*argv)[2])) {
 321                 interface_opt_a = 1;
 322                 --argc;
 323                 ++argv;
 324         }
 325 #endif
 326
 327         if (argc <= 1) {
 328 #ifdef CONFIG_FEATURE_IFCONFIG_STATUS
 329                 return display_interfaces(argc ? *argv : NULL);
 330 #else
 331                 bb_error_msg_and_die
 332                         ("ifconfig was not compiled with interface status display support.");
 333 #endif
 334         }
 335
 336         /* Create a channel to the NET kernel. */
 337         if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
 338                 bb_perror_msg_and_die("socket");
 339         }
 340
 341         /* get interface name */
 342         safe_strncpy(ifr.ifr_name, *argv, IFNAMSIZ);
 343
 344         /* Process the remaining arguments. */
 345         while (*++argv != (char *) NULL) {
 346                 p = *argv;
 347                 mask = N_MASK;
 348                 if (*p == '-') {        /* If the arg starts with '-'... */
 349                         ++p;            /*    advance past it and */
 350                         mask = M_MASK;  /*    set the appropriate mask. */
 351                 }
 352                 for (op = OptArray; op->name; op++) {   /* Find table entry. */
 353                         if (strcmp(p, op->name) == 0) { /* If name matches... */
 354                                 if ((mask &= op->flags)) {      /* set the mask and go. */
 355                                         goto FOUND_ARG;;
 356                                 }
 357                                 /* If we get here, there was a valid arg with an */
 358                                 /* invalid '-' prefix. */
 359                                 ++goterr;
 360                                 goto LOOP;
 361                         }
 362                 }
 363
 364                 /* We fell through, so treat as possible hostname. */
 365                 a1op = Arg1Opt + (sizeof(Arg1Opt) / sizeof(Arg1Opt[0])) - 1;
 366                 mask = op->arg_flags;
 367                 goto HOSTNAME;
 368
 369           FOUND_ARG:
 370                 if (mask & ARG_MASK) {
 371                         mask = op->arg_flags;
 372                         a1op = Arg1Opt + (op - OptArray);
 373                         if (mask & A_NETMASK & did_flags) {
 374                                 bb_show_usage();
 375                         }
 376                         if (*++argv == NULL) {
 377                                 if (mask & A_ARG_REQ) {
 378                                         bb_show_usage();
 379                                 } else {
 380                                         --argv;
 381                                         mask &= A_SET_AFTER;    /* just for broadcast */
 382                                 }
 383                         } else {        /* got an arg so process it */
 384                           HOSTNAME:
 385                                 did_flags |= (mask & (A_NETMASK|A_HOSTNAME));
 386                                 if (mask & A_CAST_HOST_COPY) {
 387 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 388                                         if (mask & A_CAST_RESOLVE) {
 389 #endif
 390 #ifdef CONFIG_FEATURE_IPV6
 391                                                 char *prefix;
 392                                                 int prefix_len = 0;
 393 #endif
 394
 395                                                 safe_strncpy(host, *argv, (sizeof host));
 396 #ifdef CONFIG_FEATURE_IPV6
 397                                                 if ((prefix = strchr(host, '/'))) {
 398                                                         if (safe_strtoi(prefix + 1, &prefix_len) ||
 399                                                                 (prefix_len < 0) || (prefix_len > 128))
 400                                                         {
 401                                                                 ++goterr;
 402                                                                 goto LOOP;
 403                                                         }
 404                                                         *prefix = 0;
 405                                                 }
 406 #endif
 407
 408                                                 sai.sin_family = AF_INET;
 409                                                 sai.sin_port = 0;
 410                                                 if (!strcmp(host, bb_INET_default)) {
 411                                                         /* Default is special, meaning 0.0.0.0. */
 412                                                         sai.sin_addr.s_addr = INADDR_ANY;
 413 #ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 414                                                 } else if (((host[0] == '+') && !host[1]) && (mask & A_BROADCAST) &&
 415                                                                    (did_flags & (A_NETMASK|A_HOSTNAME)) == (A_NETMASK|A_HOSTNAME)) {
 416                                                         /* + is special, meaning broadcast is derived. */
 417                                                         sai.sin_addr.s_addr = (~sai_netmask) | (sai_hostname & sai_netmask);
 418 #endif
 419 #ifdef CONFIG_FEATURE_IPV6
 420                                                 } else if (inet_pton(AF_INET6, host, &sai6.sin6_addr) > 0) {
 421                                                         int sockfd6;
 422                                                         struct in6_ifreq ifr6;
 423
 424                                                         memcpy((char *) &ifr6.ifr6_addr,
 425                                                                    (char *) &sai6.sin6_addr,
 426                                                                    sizeof(struct in6_addr));
 427
 428                                                         /* Create a channel to the NET kernel. */
 429                                                         if ((sockfd6 = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
 430                                                                 bb_perror_msg_and_die("socket6");
 431                                                         }
 432                                                         if (ioctl(sockfd6, SIOGIFINDEX, &ifr) < 0) {
 433                                                                 perror("SIOGIFINDEX");
 434                                                                 ++goterr;
 435                                                                 continue;
 436                                                         }
 437                                                         ifr6.ifr6_ifindex = ifr.ifr_ifindex;
 438                                                         ifr6.ifr6_prefixlen = prefix_len;
 439                                                         if (ioctl(sockfd6, a1op->selector, &ifr6) < 0) {
 440                                                                 perror(a1op->name);
 441                                                                 ++goterr;
 442                                                         }
 443                                                         continue;
 444 #endif
 445                                                 } else if (inet_aton(host, &sai.sin_addr) == 0) {
 446                                                         /* It's not a dotted quad. */
 447                                                         struct hostent *hp;
 448                                                         if ((hp = gethostbyname(host)) == (struct hostent *)NULL) {
 449                                                                 ++goterr;
 450                                                                 continue;
 451                                                         }
 452                                                         memcpy((char *) &sai.sin_addr, (char *) hp->h_addr_list[0],
 453                                                         sizeof(struct in_addr));
 454                                                 }
 455 #ifdef CONFIG_FEATURE_IFCONFIG_BROADCAST_PLUS
 456                                                 if (mask & A_HOSTNAME) {
 457                                                         sai_hostname = sai.sin_addr.s_addr;
 458                                                 }
 459                                                 if (mask & A_NETMASK) {
 460                                                         sai_netmask = sai.sin_addr.s_addr;
 461                                                 }
 462 #endif
 463                                                 p = (char *) &sai;
 464 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 465                                         } else {        /* A_CAST_HOST_COPY_IN_ETHER */
 466                                                 /* This is the "hw" arg case. */
 467                                                 if (strcmp("ether", *argv) || (*++argv == NULL)) {
 468                                                         bb_show_usage();
 469                                                 }
 470                                                 safe_strncpy(host, *argv, (sizeof host));
 471                                                 if (in_ether(host, &sa)) {
 472                                                         bb_error_msg("invalid hw-addr %s", host);
 473                                                         ++goterr;
 474                                                         continue;
 475                                                 }
 476                                                 p = (char *) &sa;
 477                                         }
 478 #endif
 479                                         memcpy((((char *) (&ifr)) + a1op->ifr_offset),
 480                                                    p, sizeof(struct sockaddr));
 481                                 } else {
 482                                         unsigned int i = strtoul(*argv, NULL, 0);
 483
 484                                         p = ((char *) (&ifr)) + a1op->ifr_offset;
 485 #ifdef CONFIG_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 486                                         if (mask & A_MAP_TYPE) {
 487                                                 if (ioctl(sockfd, SIOCGIFMAP, &ifr) < 0) {
 488                                                         ++goterr;
 489                                                         continue;
 490                                                 }
 491                                                 if ((mask & A_MAP_UCHAR) == A_MAP_UCHAR) {
 492                                                         *((unsigned char *) p) = i;
 493                                                 } else if (mask & A_MAP_USHORT) {
 494                                                         *((unsigned short *) p) = i;
 495                                                 } else {
 496                                                         *((unsigned long *) p) = i;
 497                                                 }
 498                                         } else
 499 #endif
 500                                         if (mask & A_CAST_CHAR_PTR) {
 501                                                 *((caddr_t *) p) = (caddr_t) i;
 502                                         } else {        /* A_CAST_INT */
 503                                                 *((int *) p) = i;
 504                                         }
 505                                 }
 506
 507                                 if (ioctl(sockfd, a1op->selector, &ifr) < 0) {
 508                                         perror(a1op->name);
 509                                         ++goterr;
 510                                         continue;
 511                                 }
 512 #ifdef QUESTIONABLE_ALIAS_CASE
 513                                 if (mask & A_COLON_CHK) {
 514                                         /*
 515                                          * Don't do the set_flag() if the address is an alias with
 516                                          * a - at the end, since it's deleted already! - Roman
 517                                          *
 518                                          * Should really use regex.h here, not sure though how well
 519                                          * it'll go with the cross-platform support etc.
 520                                          */
 521                                         char *ptr;
 522                                         short int found_colon = 0;
 523
 524                                         for (ptr = ifr.ifr_name; *ptr; ptr++) {
 525                                                 if (*ptr == ':') {
 526                                                         found_colon++;
 527                                                 }
 528                                         }
 529
 530                                         if (found_colon && *(ptr - 1) == '-') {
 531                                                 continue;
 532                                         }
 533                                 }
 534 #endif
 535                         }
 536                         if (!(mask & A_SET_AFTER)) {
 537                                 continue;
 538                         }
 539                         mask = N_SET;
 540                 }
 541
 542                 if (ioctl(sockfd, SIOCGIFFLAGS, &ifr) < 0) {
 543                         perror("SIOCGIFFLAGS");
 544                         ++goterr;
 545                 } else {
 546                         selector = op->selector;
 547                         if (mask & SET_MASK) {
 548                                 ifr.ifr_flags |= selector;
 549                         } else {
 550                                 ifr.ifr_flags &= ~selector;
 551                         }
 552                         if (ioctl(sockfd, SIOCSIFFLAGS, &ifr) < 0) {
 553                                 perror("SIOCSIFFLAGS");
 554                                 ++goterr;
 555                         }
 556                 }
 557           LOOP:
 558                 continue;
 559         }                                       /* end of while-loop */
 560
 561         return goterr;
 562 }
 563
 564 #ifdef CONFIG_FEATURE_IFCONFIG_HW
 565 /* Input an Ethernet address and convert to binary. */
 566 static int in_ether(char *bufp, struct sockaddr *sap)
 567 {
 568         unsigned char *ptr;
 569         int i, j;
 570         unsigned char val;
 571         unsigned char c;
 572
 573         sap->sa_family = ARPHRD_ETHER;
 574         ptr = sap->sa_data;
 575
 576         i = 0;
 577         do {
 578                 j = val = 0;
 579
 580                 /* We might get a semicolon here - not required. */
 581                 if (i && (*bufp == ':')) {
 582                         bufp++;
 583                 }
 584
 585                 do {
 586                         c = *bufp;
 587                         if (((unsigned char)(c - '0')) <= 9) {
 588                                 c -= '0';
 589                         } else if (((unsigned char)((c|0x20) - 'a')) <= 5) {
 590                                 c = (c|0x20) - ('a'-10);
 591                         } else if (j && (c == ':' || c == 0)) {
 592                                 break;
 593                         } else {
 594                                 return -1;
 595                         }
 596                         ++bufp;
 597                         val <<= 4;
 598                         val += c;
 599                 } while (++j < 2);
 600                 *ptr++ = val;
 601         } while (++i < ETH_ALEN);
 602
 603         return (int) (*bufp);   /* Error if we don't end at end of string. */
 604 }
 605 #endif