git.maemo.org Git - busybox4maemo/blob - 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 tarball for details.
  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 #include <net/if.h>
  30 #include <net/if_arp.h>
  31 #include <netinet/in.h>
  32 #if defined(__GLIBC__) && __GLIBC__ >=2 && __GLIBC_MINOR__ >= 1
  33 #include <netpacket/packet.h>
  34 #include <net/ethernet.h>
  35 #else
  36 #include <sys/types.h>
  37 #include <netinet/if_ether.h>
  38 #endif
  39 #include "inet_common.h"
  40 #include "libbb.h"
  41
  42 #if ENABLE_FEATURE_IFCONFIG_SLIP
  43 # include <net/if_slip.h>
  44 #endif
  45
  46 /* I don't know if this is needed for busybox or not.  Anyone? */
  47 #define QUESTIONABLE_ALIAS_CASE
  48
  49
  50 /* Defines for glibc2.0 users. */
  51 #ifndef SIOCSIFTXQLEN
  52 # define SIOCSIFTXQLEN      0x8943
  53 # define SIOCGIFTXQLEN      0x8942
  54 #endif
  55
  56 /* ifr_qlen is ifru_ivalue, but it isn't present in 2.0 kernel headers */
  57 #ifndef ifr_qlen
  58 # define ifr_qlen        ifr_ifru.ifru_mtu
  59 #endif
  60
  61 #ifndef IFF_DYNAMIC
  62 # define IFF_DYNAMIC     0x8000 /* dialup device with changing addresses */
  63 #endif
  64
  65 #if ENABLE_FEATURE_IPV6
  66 struct in6_ifreq {
  67         struct in6_addr ifr6_addr;
  68         uint32_t ifr6_prefixlen;
  69         int ifr6_ifindex;
  70 };
  71 #endif
  72
  73 /*
  74  * Here are the bit masks for the "flags" member of struct options below.
  75  * N_ signifies no arg prefix; M_ signifies arg prefixed by '-'.
  76  * CLR clears the flag; SET sets the flag; ARG signifies (optional) arg.
  77  */
  78 #define N_CLR            0x01
  79 #define M_CLR            0x02
  80 #define N_SET            0x04
  81 #define M_SET            0x08
  82 #define N_ARG            0x10
  83 #define M_ARG            0x20
  84
  85 #define M_MASK           (M_CLR | M_SET | M_ARG)
  86 #define N_MASK           (N_CLR | N_SET | N_ARG)
  87 #define SET_MASK         (N_SET | M_SET)
  88 #define CLR_MASK         (N_CLR | M_CLR)
  89 #define SET_CLR_MASK     (SET_MASK | CLR_MASK)
  90 #define ARG_MASK         (M_ARG | N_ARG)
  91
  92 /*
  93  * Here are the bit masks for the "arg_flags" member of struct options below.
  94  */
  95
  96 /*
  97  * cast type:
  98  *   00 int
  99  *   01 char *
 100  *   02 HOST_COPY in_ether
 101  *   03 HOST_COPY INET_resolve
 102  */
 103 #define A_CAST_TYPE      0x03
 104 /*
 105  * map type:
 106  *   00 not a map type (mem_start, io_addr, irq)
 107  *   04 memstart (unsigned long)
 108  *   08 io_addr  (unsigned short)
 109  *   0C irq      (unsigned char)
 110  */
 111 #define A_MAP_TYPE       0x0C
 112 #define A_ARG_REQ        0x10   /* Set if an arg is required. */
 113 #define A_NETMASK        0x20   /* Set if netmask (check for multiple sets). */
 114 #define A_SET_AFTER      0x40   /* Set a flag at the end. */
 115 #define A_COLON_CHK      0x80   /* Is this needed?  See below. */
 116 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 117 #define A_HOSTNAME      0x100   /* Set if it is ip addr. */
 118 #define A_BROADCAST     0x200   /* Set if it is broadcast addr. */
 119 #else
 120 #define A_HOSTNAME          0
 121 #define A_BROADCAST         0
 122 #endif
 123
 124 /*
 125  * These defines are for dealing with the A_CAST_TYPE field.
 126  */
 127 #define A_CAST_CHAR_PTR  0x01
 128 #define A_CAST_RESOLVE   0x01
 129 #define A_CAST_HOST_COPY 0x02
 130 #define A_CAST_HOST_COPY_IN_ETHER    A_CAST_HOST_COPY
 131 #define A_CAST_HOST_COPY_RESOLVE     (A_CAST_HOST_COPY | A_CAST_RESOLVE)
 132
 133 /*
 134  * These defines are for dealing with the A_MAP_TYPE field.
 135  */
 136 #define A_MAP_ULONG      0x04   /* memstart */
 137 #define A_MAP_USHORT     0x08   /* io_addr */
 138 #define A_MAP_UCHAR      0x0C   /* irq */
 139
 140 /*
 141  * Define the bit masks signifying which operations to perform for each arg.
 142  */
 143
 144 #define ARG_METRIC       (A_ARG_REQ /*| A_CAST_INT*/)
 145 #define ARG_MTU          (A_ARG_REQ /*| A_CAST_INT*/)
 146 #define ARG_TXQUEUELEN   (A_ARG_REQ /*| A_CAST_INT*/)
 147 #define ARG_MEM_START    (A_ARG_REQ | A_MAP_ULONG)
 148 #define ARG_IO_ADDR      (A_ARG_REQ | A_MAP_ULONG)
 149 #define ARG_IRQ          (A_ARG_REQ | A_MAP_UCHAR)
 150 #define ARG_DSTADDR      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE)
 151 #define ARG_NETMASK      (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_NETMASK)
 152 #define ARG_BROADCAST    (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_BROADCAST)
 153 #define ARG_HW           (A_ARG_REQ | A_CAST_HOST_COPY_IN_ETHER)
 154 #define ARG_POINTOPOINT  (A_ARG_REQ | A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER)
 155 #define ARG_KEEPALIVE    (A_ARG_REQ | A_CAST_CHAR_PTR)
 156 #define ARG_OUTFILL      (A_ARG_REQ | A_CAST_CHAR_PTR)
 157 #define ARG_HOSTNAME     (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER | A_COLON_CHK | A_HOSTNAME)
 158 #define ARG_ADD_DEL      (A_CAST_HOST_COPY_RESOLVE | A_SET_AFTER)
 159
 160
 161 /*
 162  * Set up the tables.  Warning!  They must have corresponding order!
 163  */
 164
 165 struct arg1opt {
 166         const char *name;
 167         unsigned short selector;
 168         unsigned short ifr_offset;
 169 };
 170
 171 struct options {
 172         const char *name;
 173 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 174         const unsigned int flags:6;
 175         const unsigned int arg_flags:10;
 176 #else
 177         const unsigned char flags;
 178         const unsigned char arg_flags;
 179 #endif
 180         const unsigned short selector;
 181 };
 182
 183 #define ifreq_offsetof(x)  offsetof(struct ifreq, x)
 184
 185 static const struct arg1opt Arg1Opt[] = {
 186         { "SIFMETRIC",  SIOCSIFMETRIC,  ifreq_offsetof(ifr_metric) },
 187         { "SIFMTU",     SIOCSIFMTU,     ifreq_offsetof(ifr_mtu) },
 188         { "SIFTXQLEN",  SIOCSIFTXQLEN,  ifreq_offsetof(ifr_qlen) },
 189         { "SIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr) },
 190         { "SIFNETMASK", SIOCSIFNETMASK, ifreq_offsetof(ifr_netmask) },
 191         { "SIFBRDADDR", SIOCSIFBRDADDR, ifreq_offsetof(ifr_broadaddr) },
 192 #if ENABLE_FEATURE_IFCONFIG_HW
 193         { "SIFHWADDR",  SIOCSIFHWADDR,  ifreq_offsetof(ifr_hwaddr) },
 194 #endif
 195         { "SIFDSTADDR", SIOCSIFDSTADDR, ifreq_offsetof(ifr_dstaddr) },
 196 #ifdef SIOCSKEEPALIVE
 197         { "SKEEPALIVE", SIOCSKEEPALIVE, ifreq_offsetof(ifr_data) },
 198 #endif
 199 #ifdef SIOCSOUTFILL
 200         { "SOUTFILL",   SIOCSOUTFILL,   ifreq_offsetof(ifr_data) },
 201 #endif
 202 #if ENABLE_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 203         { "SIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.mem_start) },
 204         { "SIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.base_addr) },
 205         { "SIFMAP",     SIOCSIFMAP,     ifreq_offsetof(ifr_map.irq) },
 206 #endif
 207         /* Last entry if for unmatched (possibly hostname) arg. */
 208 #if ENABLE_FEATURE_IPV6
 209         { "SIFADDR",    SIOCSIFADDR,    ifreq_offsetof(ifr_addr) }, /* IPv6 version ignores the offset */
 210         { "DIFADDR",    SIOCDIFADDR,    ifreq_offsetof(ifr_addr) }, /* IPv6 version ignores the offset */
 211 #endif
 212         { "SIFADDR",    SIOCSIFADDR,    ifreq_offsetof(ifr_addr) },
 213 };
 214
 215 static const struct options OptArray[] = {
 216         { "metric",      N_ARG,         ARG_METRIC,      0 },
 217         { "mtu",         N_ARG,         ARG_MTU,         0 },
 218         { "txqueuelen",  N_ARG,         ARG_TXQUEUELEN,  0 },
 219         { "dstaddr",     N_ARG,         ARG_DSTADDR,     0 },
 220         { "netmask",     N_ARG,         ARG_NETMASK,     0 },
 221         { "broadcast",   N_ARG | M_CLR, ARG_BROADCAST,   IFF_BROADCAST },
 222 #if ENABLE_FEATURE_IFCONFIG_HW
 223         { "hw",          N_ARG, ARG_HW,                  0 },
 224 #endif
 225         { "pointopoint", N_ARG | M_CLR, ARG_POINTOPOINT, IFF_POINTOPOINT },
 226 #ifdef SIOCSKEEPALIVE
 227         { "keepalive",   N_ARG,         ARG_KEEPALIVE,   0 },
 228 #endif
 229 #ifdef SIOCSOUTFILL
 230         { "outfill",     N_ARG,         ARG_OUTFILL,     0 },
 231 #endif
 232 #if ENABLE_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 233         { "mem_start",   N_ARG,         ARG_MEM_START,   0 },
 234         { "io_addr",     N_ARG,         ARG_IO_ADDR,     0 },
 235         { "irq",         N_ARG,         ARG_IRQ,         0 },
 236 #endif
 237 #if ENABLE_FEATURE_IPV6
 238         { "add",         N_ARG,         ARG_ADD_DEL,     0 },
 239         { "del",         N_ARG,         ARG_ADD_DEL,     0 },
 240 #endif
 241         { "arp",         N_CLR | M_SET, 0,               IFF_NOARP },
 242         { "trailers",    N_CLR | M_SET, 0,               IFF_NOTRAILERS },
 243         { "promisc",     N_SET | M_CLR, 0,               IFF_PROMISC },
 244         { "multicast",   N_SET | M_CLR, 0,               IFF_MULTICAST },
 245         { "allmulti",    N_SET | M_CLR, 0,               IFF_ALLMULTI },
 246         { "dynamic",     N_SET | M_CLR, 0,               IFF_DYNAMIC },
 247         { "up",          N_SET,         0,               (IFF_UP | IFF_RUNNING) },
 248         { "down",        N_CLR,         0,               IFF_UP },
 249         { NULL,          0,             ARG_HOSTNAME,    (IFF_UP | IFF_RUNNING) }
 250 };
 251
 252 /*
 253  * A couple of prototypes.
 254  */
 255
 256 #if ENABLE_FEATURE_IFCONFIG_HW
 257 static int in_ether(const char *bufp, struct sockaddr *sap);
 258 #endif
 259
 260 /*
 261  * Our main function.
 262  */
 263
 264 int ifconfig_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 265 int ifconfig_main(int argc, char **argv)
 266 {
 267         struct ifreq ifr;
 268         struct sockaddr_in sai;
 269 #if ENABLE_FEATURE_IFCONFIG_HW
 270         struct sockaddr sa;
 271 #endif
 272         const struct arg1opt *a1op;
 273         const struct options *op;
 274         int sockfd;                     /* socket fd we use to manipulate stuff with */
 275         int selector;
 276 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 277         unsigned int mask;
 278         unsigned int did_flags;
 279         unsigned int sai_hostname, sai_netmask;
 280 #else
 281         unsigned char mask;
 282         unsigned char did_flags;
 283 #endif
 284         char *p;
 285         /*char host[128];*/
 286         const char *host = NULL; /* make gcc happy */
 287
 288         did_flags = 0;
 289 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 290         sai_hostname = 0;
 291         sai_netmask = 0;
 292 #endif
 293
 294         /* skip argv[0] */
 295         ++argv;
 296         --argc;
 297
 298 #if ENABLE_FEATURE_IFCONFIG_STATUS
 299         if (argc > 0 && (argv[0][0] == '-' && argv[0][1] == 'a' && !argv[0][2])) {
 300                 interface_opt_a = 1;
 301                 --argc;
 302                 ++argv;
 303         }
 304 #endif
 305
 306         if (argc <= 1) {
 307 #if ENABLE_FEATURE_IFCONFIG_STATUS
 308                 return display_interfaces(argc ? *argv : NULL);
 309 #else
 310                 bb_error_msg_and_die("no support for status display");
 311 #endif
 312         }
 313
 314         /* Create a channel to the NET kernel. */
 315         sockfd = xsocket(AF_INET, SOCK_DGRAM, 0);
 316
 317         /* get interface name */
 318         safe_strncpy(ifr.ifr_name, *argv, IFNAMSIZ);
 319
 320         /* Process the remaining arguments. */
 321         while (*++argv != (char *) NULL) {
 322                 p = *argv;
 323                 mask = N_MASK;
 324                 if (*p == '-') {        /* If the arg starts with '-'... */
 325                         ++p;            /*    advance past it and */
 326                         mask = M_MASK;  /*    set the appropriate mask. */
 327                 }
 328                 for (op = OptArray; op->name; op++) {   /* Find table entry. */
 329                         if (strcmp(p, op->name) == 0) { /* If name matches... */
 330                                 mask &= op->flags;
 331                                 if (mask)       /* set the mask and go. */
 332                                         goto FOUND_ARG;
 333                                 /* If we get here, there was a valid arg with an */
 334                                 /* invalid '-' prefix. */
 335                                 bb_error_msg_and_die("bad: '%s'", p-1);
 336                         }
 337                 }
 338
 339                 /* We fell through, so treat as possible hostname. */
 340                 a1op = Arg1Opt + ARRAY_SIZE(Arg1Opt) - 1;
 341                 mask = op->arg_flags;
 342                 goto HOSTNAME;
 343
 344  FOUND_ARG:
 345                 if (mask & ARG_MASK) {
 346                         mask = op->arg_flags;
 347                         a1op = Arg1Opt + (op - OptArray);
 348                         if (mask & A_NETMASK & did_flags)
 349                                 bb_show_usage();
 350                         if (*++argv == NULL) {
 351                                 if (mask & A_ARG_REQ)
 352                                         bb_show_usage();
 353                                 --argv;
 354                                 mask &= A_SET_AFTER;    /* just for broadcast */
 355                         } else {        /* got an arg so process it */
 356  HOSTNAME:
 357                                 did_flags |= (mask & (A_NETMASK|A_HOSTNAME));
 358                                 if (mask & A_CAST_HOST_COPY) {
 359 #if ENABLE_FEATURE_IFCONFIG_HW
 360                                         if (mask & A_CAST_RESOLVE) {
 361 #endif
 362 #if ENABLE_FEATURE_IPV6
 363                                                 char *prefix;
 364                                                 int prefix_len = 0;
 365 #endif
 366                                                 /*safe_strncpy(host, *argv, (sizeof host));*/
 367                                                 host = *argv;
 368 #if ENABLE_FEATURE_IPV6
 369                                                 prefix = strchr(host, '/');
 370                                                 if (prefix) {
 371                                                         prefix_len = xatou_range(prefix + 1, 0, 128);
 372                                                         *prefix = '\0';
 373                                                 }
 374 #endif
 375                                                 sai.sin_family = AF_INET;
 376                                                 sai.sin_port = 0;
 377                                                 if (!strcmp(host, bb_str_default)) {
 378                                                         /* Default is special, meaning 0.0.0.0. */
 379                                                         sai.sin_addr.s_addr = INADDR_ANY;
 380                                                 }
 381 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 382                                                 else if ((host[0] == '+' && !host[1]) && (mask & A_BROADCAST)
 383                                                  && (did_flags & (A_NETMASK|A_HOSTNAME)) == (A_NETMASK|A_HOSTNAME)
 384                                                 ) {
 385                                                         /* + is special, meaning broadcast is derived. */
 386                                                         sai.sin_addr.s_addr = (~sai_netmask) | (sai_hostname & sai_netmask);
 387                                                 }
 388 #endif
 389                                                 else {
 390                                                         len_and_sockaddr *lsa;
 391                                                         if (strcmp(host, "inet") == 0)
 392                                                                 continue; /* compat stuff */
 393                                                         lsa = xhost2sockaddr(host, 0);
 394 #if ENABLE_FEATURE_IPV6
 395                                                         if (lsa->u.sa.sa_family == AF_INET6) {
 396                                                                 int sockfd6;
 397                                                                 struct in6_ifreq ifr6;
 398
 399                                                                 memcpy((char *) &ifr6.ifr6_addr,
 400                                                                                 (char *) &(lsa->u.sin6.sin6_addr),
 401                                                                                 sizeof(struct in6_addr));
 402
 403                                                                 /* Create a channel to the NET kernel. */
 404                                                                 sockfd6 = xsocket(AF_INET6, SOCK_DGRAM, 0);
 405                                                                 xioctl(sockfd6, SIOGIFINDEX, &ifr);
 406                                                                 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
 407                                                                 ifr6.ifr6_prefixlen = prefix_len;
 408                                                                 ioctl_or_perror_and_die(sockfd6, a1op->selector, &ifr6, "SIOC%s", a1op->name);
 409                                                                 if (ENABLE_FEATURE_CLEAN_UP)
 410                                                                         free(lsa);
 411                                                                 continue;
 412                                                         }
 413 #endif
 414                                                         sai.sin_addr = lsa->u.sin.sin_addr;
 415                                                         if (ENABLE_FEATURE_CLEAN_UP)
 416                                                                 free(lsa);
 417                                                 }
 418 #if ENABLE_FEATURE_IFCONFIG_BROADCAST_PLUS
 419                                                 if (mask & A_HOSTNAME)
 420                                                         sai_hostname = sai.sin_addr.s_addr;
 421                                                 if (mask & A_NETMASK)
 422                                                         sai_netmask = sai.sin_addr.s_addr;
 423 #endif
 424                                                 p = (char *) &sai;
 425 #if ENABLE_FEATURE_IFCONFIG_HW
 426                                         } else {        /* A_CAST_HOST_COPY_IN_ETHER */
 427                                                 /* This is the "hw" arg case. */
 428                                                 if (strcmp("ether", *argv) || !*++argv)
 429                                                         bb_show_usage();
 430                                                 /*safe_strncpy(host, *argv, sizeof(host));*/
 431                                                 host = *argv;
 432                                                 if (in_ether(host, &sa))
 433                                                         bb_error_msg_and_die("invalid hw-addr %s", host);
 434                                                 p = (char *) &sa;
 435                                         }
 436 #endif
 437                                         memcpy( (((char *)&ifr) + a1op->ifr_offset),
 438                                                    p, sizeof(struct sockaddr));
 439                                 } else {
 440                                         /* FIXME: error check?? */
 441                                         unsigned long i = strtoul(*argv, NULL, 0);
 442                                         p = ((char *)&ifr) + a1op->ifr_offset;
 443 #if ENABLE_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 444                                         if (mask & A_MAP_TYPE) {
 445                                                 xioctl(sockfd, SIOCGIFMAP, &ifr);
 446                                                 if ((mask & A_MAP_UCHAR) == A_MAP_UCHAR)
 447                                                         *((unsigned char *) p) = i;
 448                                                 else if (mask & A_MAP_USHORT)
 449                                                         *((unsigned short *) p) = i;
 450                                                 else
 451                                                         *((unsigned long *) p) = i;
 452                                         } else
 453 #endif
 454                                         if (mask & A_CAST_CHAR_PTR)
 455                                                 *((caddr_t *) p) = (caddr_t) i;
 456                                         else    /* A_CAST_INT */
 457                                                 *((int *) p) = i;
 458                                 }
 459
 460                                 ioctl_or_perror_and_die(sockfd, a1op->selector, &ifr, "SIOC%s", a1op->name);
 461 #ifdef QUESTIONABLE_ALIAS_CASE
 462                                 if (mask & A_COLON_CHK) {
 463                                         /*
 464                                          * Don't do the set_flag() if the address is an alias with
 465                                          * a '-' at the end, since it's deleted already! - Roman
 466                                          *
 467                                          * Should really use regex.h here, not sure though how well
 468                                          * it'll go with the cross-platform support etc.
 469                                          */
 470                                         char *ptr;
 471                                         short int found_colon = 0;
 472                                         for (ptr = ifr.ifr_name; *ptr; ptr++)
 473                                                 if (*ptr == ':')
 474                                                         found_colon++;
 475                                         if (found_colon && ptr[-1] == '-')
 476                                                 continue;
 477                                 }
 478 #endif
 479                         }
 480                         if (!(mask & A_SET_AFTER))
 481                                 continue;
 482                         mask = N_SET;
 483                 }
 484
 485                 xioctl(sockfd, SIOCGIFFLAGS, &ifr);
 486                 selector = op->selector;
 487                 if (mask & SET_MASK)
 488                         ifr.ifr_flags |= selector;
 489                 else
 490                         ifr.ifr_flags &= ~selector;
 491                 xioctl(sockfd, SIOCSIFFLAGS, &ifr);
 492         } /* while () */
 493
 494         if (ENABLE_FEATURE_CLEAN_UP)
 495                 close(sockfd);
 496         return 0;
 497 }
 498
 499 #if ENABLE_FEATURE_IFCONFIG_HW
 500 /* Input an Ethernet address and convert to binary. */
 501 static int in_ether(const char *bufp, struct sockaddr *sap)
 502 {
 503         char *ptr;
 504         int i, j;
 505         unsigned char val;
 506         unsigned char c;
 507
 508         sap->sa_family = ARPHRD_ETHER;
 509         ptr = sap->sa_data;
 510
 511         i = 0;
 512         do {
 513                 j = val = 0;
 514
 515                 /* We might get a semicolon here - not required. */
 516                 if (i && (*bufp == ':')) {
 517                         bufp++;
 518                 }
 519
 520                 do {
 521                         c = *bufp;
 522                         if (((unsigned char)(c - '0')) <= 9) {
 523                                 c -= '0';
 524                         } else if (((unsigned char)((c|0x20) - 'a')) <= 5) {
 525                                 c = (c|0x20) - ('a'-10);
 526                         } else if (j && (c == ':' || c == 0)) {
 527                                 break;
 528                         } else {
 529                                 return -1;
 530                         }
 531                         ++bufp;
 532                         val <<= 4;
 533                         val += c;
 534                 } while (++j < 2);
 535                 *ptr++ = val;
 536         } while (++i < ETH_ALEN);
 537
 538         return *bufp; /* Error if we don't end at end of string. */
 539 }
 540 #endif