networking/ifconfig.c

   1 /* vi: set sw=4 ts=4: */
   2 /* ifconfig
   3  *
   4  * Similar to the standard Unix ifconfig, but with only the necessary
   5  * parts for AF_INET, and without any printing of if info (for now).
   6  *
   7  * Bjorn Wesen, Axis Communications AB
   8  *
   9  *
  10  * Authors of the original ifconfig was:
  11  *              Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
  12  *
  13  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  14  */
  15
  16 /*
  17  * Heavily modified by Manuel Novoa III       Mar 6, 2001
  18  *
  19  * From initial port to busybox, removed most of the redundancy by
  20  * converting to a table-driven approach.  Added several (optional)
  21  * args missing from initial port.
  22  *
  23  * Still missing:  media, tunnel.
  24  *
  25  * 2002-04-20
  26  * IPV6 support added by Bart Visscher <magick@linux-fan.com>
  27  */
  28
  29 //usage:#define ifconfig_trivial_usage
  30 //usage:        IF_FEATURE_IFCONFIG_STATUS("[-a]") " interface [address]"
  31 //usage:#define ifconfig_full_usage "\n\n"
  32 //usage:       "Configure a network interface\n"
  33 //usage:     "\nOptions:"
  34 //usage:     "\n"
  35 //usage:        IF_FEATURE_IPV6(
  36 //usage:       "        [add ADDRESS[/PREFIXLEN]]\n")
  37 //usage:        IF_FEATURE_IPV6(
  38 //usage:       "        [del ADDRESS[/PREFIXLEN]]\n")
  39 //usage:       "        [[-]broadcast [ADDRESS]] [[-]pointopoint [ADDRESS]]\n"
  40 //usage:       "        [netmask ADDRESS] [dstaddr ADDRESS]\n"
  41 //usage:        IF_FEATURE_IFCONFIG_SLIP(
  42 //usage:       "        [outfill NN] [keepalive NN]\n")
  43 //usage:       "        " IF_FEATURE_IFCONFIG_HW("[hw ether" IF_FEATURE_HWIB("|infiniband")" ADDRESS] ") "[metric NN] [mtu NN]\n"
  44 //usage:       "        [[-]trailers] [[-]arp] [[-]allmulti]\n"
  45 //usage:       "        [multicast] [[-]promisc] [txqueuelen NN] [[-]dynamic]\n"
  46 //usage:        IF_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ(
  47 //usage:       "        [mem_start NN] [io_addr NN] [irq NN]\n")
  48 //usage:       "        [up|down] ..."
  49
  50 #include <net/if.h>
  51 #include <net/if_arp.h>
  52 #include <netinet/in.h>
  53 #if defined(__GLIBC__) && __GLIBC__ >=2 && __GLIBC_MINOR__ >= 1
  54 #include <netpacket/packet.h>
  55 #include <net/ethernet.h>
  56 #else
  57 #include <sys/types.h>
  58 #include <netinet/if_ether.h>
  59 #endif
  60 #include "libbb.h"
  61 #include "inet_common.h"
  62
  63 #if ENABLE_FEATURE_IFCONFIG_SLIP
  64 # include <net/if_slip.h>
  65 #endif
  66
  67 /* I don't know if this is needed for busybox or not.  Anyone? */
  68 #define QUESTIONABLE_ALIAS_CASE
  69
  70
  71 /* Defines for glibc2.0 users. */
  72 #ifndef SIOCSIFTXQLEN
  73 # define SIOCSIFTXQLEN      0x8943
  74 # define SIOCGIFTXQLEN      0x8942
  75 #endif
  76
  77 /* ifr_qlen is ifru_ivalue, but it isn't present in 2.0 kernel headers */
  78 #ifndef ifr_qlen
  79 # define ifr_qlen        ifr_ifru.ifru_mtu
  80 #endif
  81
  82 #ifndef IFF_DYNAMIC
  83 # define IFF_DYNAMIC     0x8000 /* dialup device with changing addresses */
  84 #endif
  85
  86 #if ENABLE_FEATURE_IPV6
  87 struct in6_ifreq {
  88         struct in6_addr ifr6_addr;
  89         uint32_t ifr6_prefixlen;
  90         int ifr6_ifindex;
  91 };
  92 #endif
  93
  94 /*
  95  * Here are the bit masks for the "flags" member of struct options below.
  96  * N_ signifies no arg prefix; M_ signifies arg prefixed by '-'.
  97  * CLR clears the flag; SET sets the flag; ARG signifies (optional) arg.
  98  */
  99 #define N_CLR            0x01
 100 #define M_CLR            0x02
 101 #define N_SET            0x04
 102 #define M_SET            0x08
 103 #define N_ARG            0x10
 104 #define M_ARG            0x20
 105
 106 #define M_MASK           (M_CLR | M_SET | M_ARG)
 107 #define N_MASK           (N_CLR | N_SET | N_ARG)
 108 #define SET_MASK         (N_SET | M_SET)
 109 #define CLR_MASK         (N_CLR | M_CLR)
 110 #define SET_CLR_MASK     (SET_MASK | CLR_MASK)
 111 #define ARG_MASK         (M_ARG | N_ARG)
 112
 113 /*
 114  * Here are the bit masks for the "arg_flags" member of struct options below.
 115  */
 116
 117 /*
 118  * cast type:
 119  *   00 int
 120  *   01 char *
 121  *   02 HOST_COPY in_ether
 122  *   03 HOST_COPY INET_resolve
 123  */
 124 #define A_CAST_TYPE      0x03
 125 /*
 126  * map type:
 127  *   00 not a map type (mem_start, io_addr, irq)
 128  *   04 memstart (unsigned long)
 129  *   08 io_addr  (unsigned short)
 130  *   0C irq      (unsigned char)
 131  */
 132 #define A_MAP_TYPE       0x0C
 133 #define A_ARG_REQ        0x10   /* Set if an arg is required. */
 134 #define A_NETMASK        0x20   /* Set if netmask (check for multiple sets). */
 135 #define A_SET_AFTER      0x40   /* Set a flag at the end. */
 136 #define A_COLON_CHK      0x80   /* Is this needed?  See below. */
 137 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 138 #define A_HOSTNAME      0x100   /* Set if it is ip addr. */
 139 #define A_BROADCAST     0x200   /* Set if it is broadcast addr. */
 140 #else
 141 #define A_HOSTNAME          0
 142 #define A_BROADCAST         0
 143 #endif
 144
 145 /*
 146  * These defines are for dealing with the A_CAST_TYPE field.
 147  */
 148 #define A_CAST_CHAR_PTR  0x01
 149 #define A_CAST_RESOLVE   0x01
 150 #define A_CAST_HOST_COPY 0x02
 151 #define A_CAST_HOST_COPY_IN_ETHER    A_CAST_HOST_COPY
 152 #define A_CAST_HOST_COPY_RESOLVE     (A_CAST_HOST_COPY | A_CAST_RESOLVE)
 153
 154 /*
 155  * These defines are for dealing with the A_MAP_TYPE field.
 156  */
 157 #define A_MAP_ULONG      0x04   /* memstart */
 158 #define A_MAP_USHORT     0x08   /* io_addr */
 159 #define A_MAP_UCHAR      0x0C   /* irq */
 160
 161 /*
 162  * Define the bit masks signifying which operations to perform for each arg.
 163  */
 164
 165 #define ARG_METRIC       (A_ARG_REQ /*| A_CAST_INT*/)
 166 #define ARG_MTU          (A_ARG_REQ /*| A_CAST_INT*/)
 167 #define ARG_TXQUEUELEN   (A_ARG_REQ /*| A_CAST_INT*/)
 168 #define ARG_MEM_START    (A_ARG_REQ | A_MAP_ULONG)
 169 #define ARG_IO_ADDR      (A_ARG_REQ | A_MAP_ULONG)
 170 #define ARG_IRQ          (A_ARG_REQ | A_MAP_UCHAR)
 171 #define ARG_DSTADDR      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE)
 172 #define ARG_NETMASK      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_NETMASK)
 173 #define ARG_BROADCAST    (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_BROADCAST)
 174 #define ARG_HW           (A_ARG_REQ | A_CAST_HOST_COPY_IN_ETHER)
 175 #define ARG_POINTOPOINT  (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER)
 176 #define ARG_KEEPALIVE    (A_ARG_REQ | A_CAST_CHAR_PTR)
 177 #define ARG_OUTFILL      (A_ARG_REQ | A_CAST_CHAR_PTR)
 178 #define ARG_HOSTNAME     (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_COLON_CHK | A_HOSTNAME)
 179 #define ARG_ADD_DEL      (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER)
 180
 181
 182 /*
 183  * Set up the tables.  Warning!  They must have corresponding order!
 184  */
 185
 186 struct arg1opt {
 187         const char *name;
 188         unsigned short selector;
 189         unsigned short ifr_offset;
 190 };
 191
 192 struct options {
 193         const char *name;
 194 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 195         const unsigned int flags:6;
 196         const unsigned int arg_flags:10;
 197 #else
 198         const unsigned char flags;
 199         const unsigned char arg_flags;
 200 #endif
 201         const unsigned short selector;
 202 };
 203
 204 #define ifreq_offsetof(x)  offsetof(struct ifreq, x)
 205
 206 static const struct arg1opt Arg1Opt[] = {
 207         { "SIFMETRIC",  SIOCSIFMETRIC,  ifreq_offsetof(ifr_metric) },
 208         { "SIFMTU",     SIOCSIFMTU,     ifreq_offsetof(ifr_mtu) },
 209         { "SIFTXQLEN",  SIOCSIFTXQLEN,  ifreq_offsetof(ifr_qlen) },
 210         { "SIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr) },
 211         { "SIFNETMASK", SIOCSIFNETMASK, ifreq_offsetof(ifr_netmask) },
 212         { "SIFBRDADDR", SIOCSIFBRDADDR, ifreq_offsetof(ifr_broadaddr) },
 213 #if ENABLE_FEATURE_IFCONFIG_HW
 214         { "SIFHWADDR",  SIOCSIFHWADDR,  ifreq_offsetof(ifr_hwaddr) },
 215 #endif
 216         { "SIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr) },
 217 #ifdef SIOCSKEEPALIVE
 218         { "SKEEPALIVE", SIOCSKEEPALIVE, ifreq_offsetof(ifr_data) },
 219 #endif
 220 #ifdef SIOCSOUTFILL
 221         { "SOUTFILL",   SIOCSOUTFILL,   ifreq_offsetof(ifr_data) },
 222 #endif
 223 #if ENABLE_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 224         { "SIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.mem_start) },
 225         { "SIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.base_addr) },
 226         { "SIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.irq) },
 227 #endif
 228         /* Last entry if for unmatched (possibly hostname) arg. */
 229 #if ENABLE_FEATURE_IPV6
 230         { "SIFADDR",    SIOCSIFADDR,    ifreq_offsetof(ifr_addr) }, /* IPv6 version ignores the offset */
 231         { "DIFADDR",    SIOCDIFADDR,    ifreq_offsetof(ifr_addr) }, /* IPv6 version ignores the offset */
 232 #endif
 233         { "SIFADDR",    SIOCSIFADDR,    ifreq_offsetof(ifr_addr) },
 234 };
 235
 236 static const struct options OptArray[] = {
 237         { "metric",      N_ARG,         ARG_METRIC,      0 },
 238         { "mtu",         N_ARG,         ARG_MTU,         0 },
 239         { "txqueuelen",  N_ARG,         ARG_TXQUEUELEN,  0 },
 240         { "dstaddr",     N_ARG,         ARG_DSTADDR,     0 },
 241         { "netmask",     N_ARG,         ARG_NETMASK,     0 },
 242         { "broadcast",   N_ARG | M_CLR, ARG_BROADCAST,   IFF_BROADCAST },
 243 #if ENABLE_FEATURE_IFCONFIG_HW
 244         { "hw",          N_ARG,         ARG_HW,          0 },
 245 #endif
 246         { "pointopoint", N_ARG | M_CLR, ARG_POINTOPOINT, IFF_POINTOPOINT },
 247 #ifdef SIOCSKEEPALIVE
 248         { "keepalive",   N_ARG,         ARG_KEEPALIVE,   0 },
 249 #endif
 250 #ifdef SIOCSOUTFILL
 251         { "outfill",     N_ARG,         ARG_OUTFILL,     0 },
 252 #endif
 253 #if ENABLE_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 254         { "mem_start",   N_ARG,         ARG_MEM_START,   0 },
 255         { "io_addr",     N_ARG,         ARG_IO_ADDR,     0 },
 256         { "irq",         N_ARG,         ARG_IRQ,         0 },
 257 #endif
 258 #if ENABLE_FEATURE_IPV6
 259         { "add",         N_ARG,         ARG_ADD_DEL,     0 },
 260         { "del",         N_ARG,         ARG_ADD_DEL,     0 },
 261 #endif
 262         { "arp",         N_CLR | M_SET, 0,               IFF_NOARP },
 263         { "trailers",    N_CLR | M_SET, 0,               IFF_NOTRAILERS },
 264         { "promisc",     N_SET | M_CLR, 0,               IFF_PROMISC },
 265         { "multicast",   N_SET | M_CLR, 0,               IFF_MULTICAST },
 266         { "allmulti",    N_SET | M_CLR, 0,               IFF_ALLMULTI },
 267         { "dynamic",     N_SET | M_CLR, 0,               IFF_DYNAMIC },
 268         { "up",          N_SET,         0,               (IFF_UP | IFF_RUNNING) },
 269         { "down",        N_CLR,         0,               IFF_UP },
 270         { NULL,          0,             ARG_HOSTNAME,    (IFF_UP | IFF_RUNNING) }
 271 };
 272
 273 /*
 274  * A couple of prototypes.
 275  */
 276 #if ENABLE_FEATURE_IFCONFIG_HW
 277 static int in_ether(const char *bufp, struct sockaddr *sap);
 278 #endif
 279
 280 /*
 281  * Our main function.
 282  */
 283 int ifconfig_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 284 int ifconfig_main(int argc UNUSED_PARAM, char **argv)
 285 {
 286         struct ifreq ifr;
 287         struct sockaddr_in sai;
 288 #if ENABLE_FEATURE_IFCONFIG_HW
 289         struct sockaddr sa;
 290 #endif
 291         const struct arg1opt *a1op;
 292         const struct options *op;
 293         int sockfd;                     /* socket fd we use to manipulate stuff with */
 294         int selector;
 295 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 296         unsigned int mask;
 297         unsigned int did_flags;
 298         unsigned int sai_hostname, sai_netmask;
 299 #else
 300         unsigned char mask;
 301         unsigned char did_flags;
 302 #endif
 303         char *p;
 304         /*char host[128];*/
 305         const char *host = NULL; /* make gcc happy */
 306
 307         did_flags = 0;
 308 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 309         sai_hostname = 0;
 310         sai_netmask = 0;
 311 #endif
 312
 313         /* skip argv[0] */
 314         ++argv;
 315
 316 #if ENABLE_FEATURE_IFCONFIG_STATUS
 317         if (argv[0] && (argv[0][0] == '-' && argv[0][1] == 'a' && !argv[0][2])) {
 318                 interface_opt_a = 1;
 319                 ++argv;
 320         }
 321 #endif
 322
 323         if (!argv[0] || !argv[1]) { /* one or no args */
 324 #if ENABLE_FEATURE_IFCONFIG_STATUS
 325                 return display_interfaces(argv[0] /* can be NULL */);
 326 #else
 327                 bb_error_msg_and_die("no support for status display");
 328 #endif
 329         }
 330
 331         /* Create a channel to the NET kernel. */
 332         sockfd = xsocket(AF_INET, SOCK_DGRAM, 0);
 333
 334         /* get interface name */
 335         strncpy_IFNAMSIZ(ifr.ifr_name, *argv);
 336
 337         /* Process the remaining arguments. */
 338         while (*++argv != (char *) NULL) {
 339                 p = *argv;
 340                 mask = N_MASK;
 341                 if (*p == '-') {        /* If the arg starts with '-'... */
 342                         ++p;            /*    advance past it and */
 343                         mask = M_MASK;  /*    set the appropriate mask. */
 344                 }
 345                 for (op = OptArray; op->name; op++) {   /* Find table entry. */
 346                         if (strcmp(p, op->name) == 0) { /* If name matches... */
 347                                 mask &= op->flags;
 348                                 if (mask)       /* set the mask and go. */
 349                                         goto FOUND_ARG;
 350                                 /* If we get here, there was a valid arg with an */
 351                                 /* invalid '-' prefix. */
 352                                 bb_error_msg_and_die("bad: '%s'", p-1);
 353                         }
 354                 }
 355
 356                 /* We fell through, so treat as possible hostname. */
 357                 a1op = Arg1Opt + ARRAY_SIZE(Arg1Opt) - 1;
 358                 mask = op->arg_flags;
 359                 goto HOSTNAME;
 360
 361  FOUND_ARG:
 362                 if (mask & ARG_MASK) {
 363                         mask = op->arg_flags;
 364                         a1op = Arg1Opt + (op - OptArray);
 365                         if (mask & A_NETMASK & did_flags)
 366                                 bb_show_usage();
 367                         if (*++argv == NULL) {
 368                                 if (mask & A_ARG_REQ)
 369                                         bb_show_usage();
 370                                 --argv;
 371                                 mask &= A_SET_AFTER;    /* just for broadcast */
 372                         } else {        /* got an arg so process it */
 373  HOSTNAME:
 374                                 did_flags |= (mask & (A_NETMASK|A_HOSTNAME));
 375                                 if (mask & A_CAST_HOST_COPY) {
 376 #if ENABLE_FEATURE_IFCONFIG_HW
 377                                         if (mask & A_CAST_RESOLVE) {
 378 #endif
 379 #if ENABLE_FEATURE_IPV6
 380                                                 char *prefix;
 381                                                 int prefix_len = 0;
 382 #endif
 383                                                 /*safe_strncpy(host, *argv, (sizeof host));*/
 384                                                 host = *argv;
 385 #if ENABLE_FEATURE_IPV6
 386                                                 prefix = strchr(host, '/');
 387                                                 if (prefix) {
 388                                                         prefix_len = xatou_range(prefix + 1, 0, 128);
 389                                                         *prefix = '\0';
 390                                                 }
 391 #endif
 392                                                 sai.sin_family = AF_INET;
 393                                                 sai.sin_port = 0;
 394                                                 if (strcmp(host, "default") == 0) {
 395                                                         /* Default is special, meaning 0.0.0.0. */
 396                                                         sai.sin_addr.s_addr = INADDR_ANY;
 397                                                 }
 398 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 399                                                 else if ((host[0] == '+' && !host[1]) && (mask & A_BROADCAST)
 400                                                  && (did_flags & (A_NETMASK|A_HOSTNAME)) == (A_NETMASK|A_HOSTNAME)
 401                                                 ) {
 402                                                         /* + is special, meaning broadcast is derived. */
 403                                                         sai.sin_addr.s_addr = (~sai_netmask) | (sai_hostname & sai_netmask);
 404                                                 }
 405 #endif
 406                                                 else {
 407                                                         len_and_sockaddr *lsa;
 408                                                         if (strcmp(host, "inet") == 0)
 409                                                                 continue; /* compat stuff */
 410                                                         lsa = xhost2sockaddr(host, 0);
 411 #if ENABLE_FEATURE_IPV6
 412                                                         if (lsa->u.sa.sa_family == AF_INET6) {
 413                                                                 int sockfd6;
 414                                                                 struct in6_ifreq ifr6;
 415
 416                                                                 memcpy((char *) &ifr6.ifr6_addr,
 417                                                                                 (char *) &(lsa->u.sin6.sin6_addr),
 418                                                                                 sizeof(struct in6_addr));
 419
 420                                                                 /* Create a channel to the NET kernel. */
 421                                                                 sockfd6 = xsocket(AF_INET6, SOCK_DGRAM, 0);
 422                                                                 xioctl(sockfd6, SIOGIFINDEX, &ifr);
 423                                                                 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
 424                                                                 ifr6.ifr6_prefixlen = prefix_len;
 425                                                                 ioctl_or_perror_and_die(sockfd6, a1op->selector, &ifr6, "SIOC%s", a1op->name);
 426                                                                 if (ENABLE_FEATURE_CLEAN_UP)
 427                                                                         free(lsa);
 428                                                                 continue;
 429                                                         }
 430 #endif
 431                                                         sai.sin_addr = lsa->u.sin.sin_addr;
 432                                                         if (ENABLE_FEATURE_CLEAN_UP)
 433                                                                 free(lsa);
 434                                                 }
 435 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 436                                                 if (mask & A_HOSTNAME)
 437                                                         sai_hostname = sai.sin_addr.s_addr;
 438                                                 if (mask & A_NETMASK)
 439                                                         sai_netmask = sai.sin_addr.s_addr;
 440 #endif
 441                                                 p = (char *) &sai;
 442 #if ENABLE_FEATURE_IFCONFIG_HW
 443                                         } else {        /* A_CAST_HOST_COPY_IN_ETHER */
 444                                                 /* This is the "hw" arg case. */
 445                                                 smalluint hw_class= index_in_substrings("ether\0"
 446                                                                 IF_FEATURE_HWIB("infiniband\0"), *argv) + 1;
 447                                                 if (!hw_class || !*++argv)
 448                                                         bb_show_usage();
 449                                                 /*safe_strncpy(host, *argv, sizeof(host));*/
 450                                                 host = *argv;
 451                                                 if (hw_class == 1 ? in_ether(host, &sa) : in_ib(host, &sa))
 452                                                         bb_error_msg_and_die("invalid hw-addr %s", host);
 453                                                 p = (char *) &sa;
 454                                         }
 455 #endif
 456                                         memcpy( (((char *)&ifr) + a1op->ifr_offset),
 457                                                    p, sizeof(struct sockaddr));
 458                                 } else {
 459                                         /* FIXME: error check?? */
 460                                         unsigned long i = strtoul(*argv, NULL, 0);
 461                                         p = ((char *)&ifr) + a1op->ifr_offset;
 462 #if ENABLE_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 463                                         if (mask & A_MAP_TYPE) {
 464                                                 xioctl(sockfd, SIOCGIFMAP, &ifr);
 465                                                 if ((mask & A_MAP_UCHAR) == A_MAP_UCHAR)
 466                                                         *((unsigned char *) p) = i;
 467                                                 else if (mask & A_MAP_USHORT)
 468                                                         *((unsigned short *) p) = i;
 469                                                 else
 470                                                         *((unsigned long *) p) = i;
 471                                         } else
 472 #endif
 473                                         if (mask & A_CAST_CHAR_PTR)
 474                                                 *((caddr_t *) p) = (caddr_t) i;
 475                                         else    /* A_CAST_INT */
 476                                                 *((int *) p) = i;
 477                                 }
 478
 479                                 ioctl_or_perror_and_die(sockfd, a1op->selector, &ifr, "SIOC%s", a1op->name);
 480 #ifdef QUESTIONABLE_ALIAS_CASE
 481                                 if (mask & A_COLON_CHK) {
 482                                         /*
 483                                          * Don't do the set_flag() if the address is an alias with
 484                                          * a '-' at the end, since it's deleted already! - Roman
 485                                          *
 486                                          * Should really use regex.h here, not sure though how well
 487                                          * it'll go with the cross-platform support etc.
 488                                          */
 489                                         char *ptr;
 490                                         short int found_colon = 0;
 491                                         for (ptr = ifr.ifr_name; *ptr; ptr++)
 492                                                 if (*ptr == ':')
 493                                                         found_colon++;
 494                                         if (found_colon && ptr[-1] == '-')
 495                                                 continue;
 496                                 }
 497 #endif
 498                         }
 499                         if (!(mask & A_SET_AFTER))
 500                                 continue;
 501                         mask = N_SET;
 502                 }
 503
 504                 xioctl(sockfd, SIOCGIFFLAGS, &ifr);
 505                 selector = op->selector;
 506                 if (mask & SET_MASK)
 507                         ifr.ifr_flags |= selector;
 508                 else
 509                         ifr.ifr_flags &= ~selector;
 510                 xioctl(sockfd, SIOCSIFFLAGS, &ifr);
 511         } /* while () */
 512
 513         if (ENABLE_FEATURE_CLEAN_UP)
 514                 close(sockfd);
 515         return 0;
 516 }
 517
 518 #if ENABLE_FEATURE_IFCONFIG_HW
 519 /* Input an Ethernet address and convert to binary. */
 520 static int in_ether(const char *bufp, struct sockaddr *sap)
 521 {
 522         char *ptr;
 523         int i, j;
 524         unsigned char val;
 525         unsigned char c;
 526
 527         sap->sa_family = ARPHRD_ETHER;
 528         ptr = (char *) sap->sa_data;
 529
 530         i = 0;
 531         do {
 532                 j = val = 0;
 533
 534                 /* We might get a semicolon here - not required. */
 535                 if (i && (*bufp == ':')) {
 536                         bufp++;
 537                 }
 538
 539                 do {
 540                         c = *bufp;
 541                         if (((unsigned char)(c - '0')) <= 9) {
 542                                 c -= '0';
 543                         } else if (((unsigned char)((c|0x20) - 'a')) <= 5) {
 544                                 c = (c|0x20) - ('a'-10);
 545                         } else if (j && (c == ':' || c == 0)) {
 546                                 break;
 547                         } else {
 548                                 return -1;
 549                         }
 550                         ++bufp;
 551                         val <<= 4;
 552                         val += c;
 553                 } while (++j < 2);
 554                 *ptr++ = val;
 555         } while (++i < ETH_ALEN);
 556
 557         return *bufp; /* Error if we don't end at end of string. */
 558 }
 559 #endif