util-linux/networking/udhcp/common.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
   4  *
   5  * Licensed under GPLv2, see file LICENSE in this tarball for details.
   6  */
   7 #include "common.h"
   8
   9 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
  10 unsigned dhcp_verbose;
  11 #endif
  12
  13 const uint8_t MAC_BCAST_ADDR[6] ALIGN2 = {
  14         0xff, 0xff, 0xff, 0xff, 0xff, 0xff
  15 };
  16
  17 /* Supported options are easily added here.
  18  * See RFC2132 for more options.
  19  * OPTION_REQ: these options are requested by udhcpc (unless -o).
  20  */
  21 const struct dhcp_optflag dhcp_optflags[] = {
  22         /* flags                                    code */
  23         { OPTION_IP                   | OPTION_REQ, 0x01 }, /* DHCP_SUBNET        */
  24         { OPTION_S32                              , 0x02 }, /* DHCP_TIME_OFFSET   */
  25         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x03 }, /* DHCP_ROUTER        */
  26 //      { OPTION_IP | OPTION_LIST                 , 0x04 }, /* DHCP_TIME_SERVER   */
  27 //      { OPTION_IP | OPTION_LIST                 , 0x05 }, /* DHCP_NAME_SERVER   */
  28         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x06 }, /* DHCP_DNS_SERVER    */
  29 //      { OPTION_IP | OPTION_LIST                 , 0x07 }, /* DHCP_LOG_SERVER    */
  30 //      { OPTION_IP | OPTION_LIST                 , 0x08 }, /* DHCP_COOKIE_SERVER */
  31         { OPTION_IP | OPTION_LIST                 , 0x09 }, /* DHCP_LPR_SERVER    */
  32         { OPTION_STRING               | OPTION_REQ, 0x0c }, /* DHCP_HOST_NAME     */
  33         { OPTION_U16                              , 0x0d }, /* DHCP_BOOT_SIZE     */
  34         { OPTION_STRING               | OPTION_REQ, 0x0f }, /* DHCP_DOMAIN_NAME   */
  35         { OPTION_IP                               , 0x10 }, /* DHCP_SWAP_SERVER   */
  36         { OPTION_STRING                           , 0x11 }, /* DHCP_ROOT_PATH     */
  37         { OPTION_U8                               , 0x17 }, /* DHCP_IP_TTL        */
  38         { OPTION_U16                              , 0x1a }, /* DHCP_MTU           */
  39         { OPTION_IP                   | OPTION_REQ, 0x1c }, /* DHCP_BROADCAST     */
  40         { OPTION_STRING                           , 0x28 }, /* DHCP_NIS_DOMAIN    */
  41         { OPTION_IP | OPTION_LIST                 , 0x29 }, /* DHCP_NIS_SERVER    */
  42         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x2a }, /* DHCP_NTP_SERVER    */
  43         { OPTION_IP | OPTION_LIST                 , 0x2c }, /* DHCP_WINS_SERVER   */
  44         { OPTION_U32                              , 0x33 }, /* DHCP_LEASE_TIME    */
  45         { OPTION_IP                               , 0x36 }, /* DHCP_SERVER_ID     */
  46         { OPTION_STRING                           , 0x38 }, /* DHCP_ERR_MESSAGE   */
  47 //TODO: must be combined with 'sname' and 'file' handling:
  48         { OPTION_STRING                           , 0x42 }, /* DHCP_TFTP_SERVER_NAME */
  49         { OPTION_STRING                           , 0x43 }, /* DHCP_BOOT_FILE     */
  50 //TODO: not a string, but a set of LASCII strings:
  51 //      { OPTION_STRING                           , 0x4D }, /* DHCP_USER_CLASS    */
  52 #if ENABLE_FEATURE_UDHCP_RFC3397
  53         { OPTION_DNS_STRING | OPTION_LIST         , 0x77 }, /* DHCP_DOMAIN_SEARCH */
  54         { OPTION_SIP_SERVERS                      , 0x78 }, /* DHCP_SIP_SERVERS   */
  55 #endif
  56         { OPTION_STATIC_ROUTES                    , 0x79 }, /* DHCP_STATIC_ROUTES */
  57         { OPTION_STRING                           , 0xfc }, /* DHCP_WPAD          */
  58
  59         /* Options below have no match in dhcp_option_strings[],
  60          * are not passed to dhcpc scripts, and cannot be specified
  61          * with "option XXX YYY" syntax in dhcpd config file.
  62          * These entries are only used internally by udhcp[cd]
  63          * to correctly encode options into packets.
  64          */
  65
  66         { OPTION_IP                               , 0x32 }, /* DHCP_REQUESTED_IP  */
  67         { OPTION_U8                               , 0x35 }, /* DHCP_MESSAGE_TYPE  */
  68         { OPTION_U16                              , 0x39 }, /* DHCP_MAX_SIZE      */
  69         { OPTION_STRING                           , 0x3c }, /* DHCP_VENDOR        */
  70 //FIXME: handling of this option is not exactly correct:
  71         { OPTION_STRING                           , 0x3d }, /* DHCP_CLIENT_ID     */
  72         { 0, 0 } /* zeroed terminating entry */
  73 };
  74
  75 /* Used for converting options from incoming packets to env variables
  76  * for udhcpc stript, and for setting options for udhcpd via
  77  * "opt OPTION_NAME OPTION_VALUE" directives in udhcpd.conf file.
  78  */
  79 /* Must match dhcp_optflags[] order */
  80 const char dhcp_option_strings[] ALIGN1 =
  81         "subnet" "\0"      /* DHCP_SUBNET         */
  82         "timezone" "\0"    /* DHCP_TIME_OFFSET    */
  83         "router" "\0"      /* DHCP_ROUTER         */
  84 //      "timesrv" "\0"     /* DHCP_TIME_SERVER    */
  85 //      "namesrv" "\0"     /* DHCP_NAME_SERVER    */
  86         "dns" "\0"         /* DHCP_DNS_SERVER     */
  87 //      "logsrv" "\0"      /* DHCP_LOG_SERVER     */
  88 //      "cookiesrv" "\0"   /* DHCP_COOKIE_SERVER  */
  89         "lprsrv" "\0"      /* DHCP_LPR_SERVER     */
  90         "hostname" "\0"    /* DHCP_HOST_NAME      */
  91         "bootsize" "\0"    /* DHCP_BOOT_SIZE      */
  92         "domain" "\0"      /* DHCP_DOMAIN_NAME    */
  93         "swapsrv" "\0"     /* DHCP_SWAP_SERVER    */
  94         "rootpath" "\0"    /* DHCP_ROOT_PATH      */
  95         "ipttl" "\0"       /* DHCP_IP_TTL         */
  96         "mtu" "\0"         /* DHCP_MTU            */
  97         "broadcast" "\0"   /* DHCP_BROADCAST      */
  98         "nisdomain" "\0"   /* DHCP_NIS_DOMAIN     */
  99         "nissrv" "\0"      /* DHCP_NIS_SERVER     */
 100         "ntpsrv" "\0"      /* DHCP_NTP_SERVER     */
 101         "wins" "\0"        /* DHCP_WINS_SERVER    */
 102         "lease" "\0"       /* DHCP_LEASE_TIME     */
 103         "serverid" "\0"    /* DHCP_SERVER_ID      */
 104         "message" "\0"     /* DHCP_ERR_MESSAGE    */
 105         "tftp" "\0"        /* DHCP_TFTP_SERVER_NAME */
 106         "bootfile" "\0"    /* DHCP_BOOT_FILE      */
 107 //      "userclass" "\0"   /* DHCP_USER_CLASS     */
 108 #if ENABLE_FEATURE_UDHCP_RFC3397
 109         "search" "\0"      /* DHCP_DOMAIN_SEARCH  */
 110 // doesn't work in udhcpd.conf since OPTION_SIP_SERVERS
 111 // is not handled yet by "string->option" conversion code:
 112         "sipsrv" "\0"      /* DHCP_SIP_SERVERS    */
 113 #endif
 114 // doesn't work in udhcpd.conf since OPTION_STATIC_ROUTES
 115 // is not handled yet by "string->option" conversion code:
 116         "staticroutes" "\0"/* DHCP_STATIC_ROUTES  */
 117         "wpad" "\0"        /* DHCP_WPAD           */
 118         ;
 119
 120 /* Lengths of the option types in binary form.
 121  * Used by:
 122  * udhcp_str2optset: to determine how many bytes to allocate.
 123  * xmalloc_optname_optval: to estimate string length
 124  * from binary option length: (option[LEN] / dhcp_option_lengths[opt_type])
 125  * is the number of elements, multiply in by one element's string width
 126  * (len_of_option_as_string[opt_type]) and you know how wide string you need.
 127  */
 128 const uint8_t dhcp_option_lengths[] ALIGN1 = {
 129         [OPTION_IP] =      4,
 130         [OPTION_IP_PAIR] = 8,
 131 //      [OPTION_BOOLEAN] = 1,
 132         [OPTION_STRING] =  1,  /* ignored by udhcp_str2optset */
 133 #if ENABLE_FEATURE_UDHCP_RFC3397
 134         [OPTION_DNS_STRING] = 1,  /* ignored by both udhcp_str2optset and xmalloc_optname_optval */
 135         [OPTION_SIP_SERVERS] = 1,
 136 #endif
 137         [OPTION_U8] =      1,
 138         [OPTION_U16] =     2,
 139 //      [OPTION_S16] =     2,
 140         [OPTION_U32] =     4,
 141         [OPTION_S32] =     4,
 142         /* Just like OPTION_STRING, we use minimum length here */
 143         [OPTION_STATIC_ROUTES] = 5,
 144 };
 145
 146
 147 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 2
 148 static void log_option(const char *pfx, const uint8_t *opt)
 149 {
 150         if (dhcp_verbose >= 2) {
 151                 char buf[256 * 2 + 2];
 152                 *bin2hex(buf, (void*) (opt + OPT_DATA), opt[OPT_LEN]) = '\0';
 153                 bb_info_msg("%s: 0x%02x %s", pfx, opt[OPT_CODE], buf);
 154         }
 155 }
 156 #else
 157 # define log_option(pfx, opt) ((void)0)
 158 #endif
 159
 160 unsigned FAST_FUNC udhcp_option_idx(const char *name)
 161 {
 162         int n = index_in_strings(dhcp_option_strings, name);
 163         if (n >= 0)
 164                 return n;
 165
 166         {
 167                 char buf[sizeof(dhcp_option_strings)];
 168                 char *d = buf;
 169                 const char *s = dhcp_option_strings;
 170                 while (s < dhcp_option_strings + sizeof(dhcp_option_strings) - 2) {
 171                         *d++ = (*s == '\0' ? ' ' : *s);
 172                         s++;
 173                 }
 174                 *d = '\0';
 175                 bb_error_msg_and_die("unknown option '%s', known options: %s", name, buf);
 176         }
 177 }
 178
 179 /* Get an option with bounds checking (warning, result is not aligned) */
 180 uint8_t* FAST_FUNC udhcp_get_option(struct dhcp_packet *packet, int code)
 181 {
 182         uint8_t *optionptr;
 183         int len;
 184         int rem;
 185         int overload = 0;
 186         enum {
 187                 FILE_FIELD101  = FILE_FIELD  * 0x101,
 188                 SNAME_FIELD101 = SNAME_FIELD * 0x101,
 189         };
 190
 191         /* option bytes: [code][len][data1][data2]..[dataLEN] */
 192         optionptr = packet->options;
 193         rem = sizeof(packet->options);
 194         while (1) {
 195                 if (rem <= 0) {
 196                         bb_error_msg("bad packet, malformed option field");
 197                         return NULL;
 198                 }
 199                 if (optionptr[OPT_CODE] == DHCP_PADDING) {
 200                         rem--;
 201                         optionptr++;
 202                         continue;
 203                 }
 204                 if (optionptr[OPT_CODE] == DHCP_END) {
 205                         if ((overload & FILE_FIELD101) == FILE_FIELD) {
 206                                 /* can use packet->file, and didn't look at it yet */
 207                                 overload |= FILE_FIELD101; /* "we looked at it" */
 208                                 optionptr = packet->file;
 209                                 rem = sizeof(packet->file);
 210                                 continue;
 211                         }
 212                         if ((overload & SNAME_FIELD101) == SNAME_FIELD) {
 213                                 /* can use packet->sname, and didn't look at it yet */
 214                                 overload |= SNAME_FIELD101; /* "we looked at it" */
 215                                 optionptr = packet->sname;
 216                                 rem = sizeof(packet->sname);
 217                                 continue;
 218                         }
 219                         break;
 220                 }
 221                 len = 2 + optionptr[OPT_LEN];
 222                 rem -= len;
 223                 if (rem < 0)
 224                         continue; /* complain and return NULL */
 225
 226                 if (optionptr[OPT_CODE] == code) {
 227                         log_option("Option found", optionptr);
 228                         return optionptr + OPT_DATA;
 229                 }
 230
 231                 if (optionptr[OPT_CODE] == DHCP_OPTION_OVERLOAD) {
 232                         overload |= optionptr[OPT_DATA];
 233                         /* fall through */
 234                 }
 235                 optionptr += len;
 236         }
 237
 238         /* log3 because udhcpc uses it a lot - very noisy */
 239         log3("Option 0x%02x not found", code);
 240         return NULL;
 241 }
 242
 243 /* Return the position of the 'end' option (no bounds checking) */
 244 int FAST_FUNC udhcp_end_option(uint8_t *optionptr)
 245 {
 246         int i = 0;
 247
 248         while (optionptr[i] != DHCP_END) {
 249                 if (optionptr[i] != DHCP_PADDING)
 250                         i += optionptr[i + OPT_LEN] + OPT_DATA-1;
 251                 i++;
 252         }
 253         return i;
 254 }
 255
 256 /* Add an option (supplied in binary form) to the options.
 257  * Option format: [code][len][data1][data2]..[dataLEN]
 258  */
 259 void FAST_FUNC udhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt)
 260 {
 261         unsigned len;
 262         uint8_t *optionptr = packet->options;
 263         unsigned end = udhcp_end_option(optionptr);
 264
 265         len = OPT_DATA + addopt[OPT_LEN];
 266         /* end position + (option code/length + addopt length) + end option */
 267         if (end + len + 1 >= DHCP_OPTIONS_BUFSIZE) {
 268 //TODO: learn how to use overflow option if we exhaust packet->options[]
 269                 bb_error_msg("option 0x%02x did not fit into the packet",
 270                                 addopt[OPT_CODE]);
 271                 return;
 272         }
 273         log_option("Adding option", addopt);
 274         memcpy(optionptr + end, addopt, len);
 275         optionptr[end + len] = DHCP_END;
 276 }
 277
 278 /* Add an one to four byte option to a packet */
 279 void FAST_FUNC udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, uint32_t data)
 280 {
 281         const struct dhcp_optflag *dh;
 282
 283         for (dh = dhcp_optflags; dh->code; dh++) {
 284                 if (dh->code == code) {
 285                         uint8_t option[6], len;
 286
 287                         option[OPT_CODE] = code;
 288                         len = dhcp_option_lengths[dh->flags & OPTION_TYPE_MASK];
 289                         option[OPT_LEN] = len;
 290                         if (BB_BIG_ENDIAN)
 291                                 data <<= 8 * (4 - len);
 292                         /* Assignment is unaligned! */
 293                         move_to_unaligned32(&option[OPT_DATA], data);
 294                         udhcp_add_binary_option(packet, option);
 295                         return;
 296                 }
 297         }
 298
 299         bb_error_msg("can't add option 0x%02x", code);
 300 }
 301
 302 /* Find option 'code' in opt_list */
 303 struct option_set* FAST_FUNC udhcp_find_option(struct option_set *opt_list, uint8_t code)
 304 {
 305         while (opt_list && opt_list->data[OPT_CODE] < code)
 306                 opt_list = opt_list->next;
 307
 308         if (opt_list && opt_list->data[OPT_CODE] == code)
 309                 return opt_list;
 310         return NULL;
 311 }
 312
 313 /* Parse string to IP in network order */
 314 int FAST_FUNC udhcp_str2nip(const char *str, void *arg)
 315 {
 316         len_and_sockaddr *lsa;
 317
 318         lsa = host_and_af2sockaddr(str, 0, AF_INET);
 319         if (!lsa)
 320                 return 0;
 321         *(uint32_t*)arg = lsa->u.sin.sin_addr.s_addr;
 322         free(lsa);
 323         return 1;
 324 }
 325
 326 /* udhcp_str2optset:
 327  * Parse string option representation to binary form and add it to opt_list.
 328  * Called to parse "udhcpc -x OPTNAME:OPTVAL"
 329  * and to parse udhcpd.conf's "opt OPTNAME OPTVAL" directives.
 330  */
 331 /* helper for the helper */
 332 static char *allocate_tempopt_if_needed(
 333                 const struct dhcp_optflag *optflag,
 334                 char *buffer,
 335                 int *length_p)
 336 {
 337         char *allocated = NULL;
 338         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_BIN) {
 339                 const char *end;
 340                 allocated = xstrdup(buffer); /* more than enough */
 341                 end = hex2bin(allocated, buffer, 255);
 342                 if (errno)
 343                         bb_error_msg_and_die("malformed hex string '%s'", buffer);
 344                 *length_p = end - allocated;
 345         }
 346         return allocated;
 347 }
 348 /* helper: add an option to the opt_list */
 349 static NOINLINE void attach_option(
 350                 struct option_set **opt_list,
 351                 const struct dhcp_optflag *optflag,
 352                 char *buffer,
 353                 int length)
 354 {
 355         struct option_set *existing, *new, **curr;
 356         char *allocated = NULL;
 357
 358         existing = udhcp_find_option(*opt_list, optflag->code);
 359         if (!existing) {
 360                 log2("Attaching option %02x to list", optflag->code);
 361                 allocated = allocate_tempopt_if_needed(optflag, buffer, &length);
 362 #if ENABLE_FEATURE_UDHCP_RFC3397
 363                 if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_DNS_STRING) {
 364                         /* reuse buffer and length for RFC1035-formatted string */
 365                         allocated = buffer = (char *)dname_enc(NULL, 0, buffer, &length);
 366                 }
 367 #endif
 368                 /* make a new option */
 369                 new = xmalloc(sizeof(*new));
 370                 new->data = xmalloc(length + OPT_DATA);
 371                 new->data[OPT_CODE] = optflag->code;
 372                 new->data[OPT_LEN] = length;
 373                 memcpy(new->data + OPT_DATA, buffer, length);
 374
 375                 curr = opt_list;
 376                 while (*curr && (*curr)->data[OPT_CODE] < optflag->code)
 377                         curr = &(*curr)->next;
 378
 379                 new->next = *curr;
 380                 *curr = new;
 381                 goto ret;
 382         }
 383
 384         if (optflag->flags & OPTION_LIST) {
 385                 unsigned old_len;
 386
 387                 /* add it to an existing option */
 388                 log2("Attaching option %02x to existing member of list", optflag->code);
 389                 allocated = allocate_tempopt_if_needed(optflag, buffer, &length);
 390                 old_len = existing->data[OPT_LEN];
 391 #if ENABLE_FEATURE_UDHCP_RFC3397
 392                 if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_DNS_STRING) {
 393                         /* reuse buffer and length for RFC1035-formatted string */
 394                         allocated = buffer = (char *)dname_enc(existing->data + OPT_DATA, old_len, buffer, &length);
 395                 }
 396 #endif
 397                 if (old_len + length < 255) {
 398                         /* actually 255 is ok too, but adding a space can overlow it */
 399
 400                         existing->data = xrealloc(existing->data, OPT_DATA + 1 + old_len + length);
 401                         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING) {
 402                                 /* add space separator between STRING options in a list */
 403                                 existing->data[OPT_DATA + old_len] = ' ';
 404                                 old_len++;
 405                         }
 406                         memcpy(existing->data + OPT_DATA + old_len, buffer, length);
 407                         existing->data[OPT_LEN] = old_len + length;
 408                 } /* else, ignore the data, we could put this in a second option in the future */
 409         } /* else, ignore the new data */
 410
 411  ret:
 412         free(allocated);
 413 }
 414
 415 int FAST_FUNC udhcp_str2optset(const char *const_str, void *arg)
 416 {
 417         struct option_set **opt_list = arg;
 418         char *opt, *val, *endptr;
 419         char *str;
 420         const struct dhcp_optflag *optflag;
 421         struct dhcp_optflag bin_optflag;
 422         unsigned optcode;
 423         int retval, length;
 424         char buffer[8] ALIGNED(4);
 425         uint16_t *result_u16 = (uint16_t *) buffer;
 426         uint32_t *result_u32 = (uint32_t *) buffer;
 427
 428         /* Cheat, the only *const* str possible is "" */
 429         str = (char *) const_str;
 430         opt = strtok(str, " \t=");
 431         if (!opt)
 432                 return 0;
 433
 434         optcode = bb_strtou(opt, NULL, 0);
 435         if (!errno && optcode < 255) {
 436                 /* Raw (numeric) option code */
 437                 bin_optflag.flags = OPTION_BIN;
 438                 bin_optflag.code = optcode;
 439                 optflag = &bin_optflag;
 440         } else {
 441                 optflag = &dhcp_optflags[udhcp_option_idx(opt)];
 442         }
 443
 444         retval = 0;
 445         do {
 446                 val = strtok(NULL, ", \t");
 447                 if (!val)
 448                         break;
 449                 length = dhcp_option_lengths[optflag->flags & OPTION_TYPE_MASK];
 450                 retval = 0;
 451                 opt = buffer; /* new meaning for variable opt */
 452                 switch (optflag->flags & OPTION_TYPE_MASK) {
 453                 case OPTION_IP:
 454                         retval = udhcp_str2nip(val, buffer);
 455                         break;
 456                 case OPTION_IP_PAIR:
 457                         retval = udhcp_str2nip(val, buffer);
 458                         val = strtok(NULL, ", \t/-");
 459                         if (!val)
 460                                 retval = 0;
 461                         if (retval)
 462                                 retval = udhcp_str2nip(val, buffer + 4);
 463                         break;
 464                 case OPTION_STRING:
 465 #if ENABLE_FEATURE_UDHCP_RFC3397
 466                 case OPTION_DNS_STRING:
 467 #endif
 468                         length = strnlen(val, 254);
 469                         if (length > 0) {
 470                                 opt = val;
 471                                 retval = 1;
 472                         }
 473                         break;
 474 //              case OPTION_BOOLEAN: {
 475 //                      static const char no_yes[] ALIGN1 = "no\0yes\0";
 476 //                      buffer[0] = retval = index_in_strings(no_yes, val);
 477 //                      retval++; /* 0 - bad; 1: "no" 2: "yes" */
 478 //                      break;
 479 //              }
 480                 case OPTION_U8:
 481                         buffer[0] = strtoul(val, &endptr, 0);
 482                         retval = (endptr[0] == '\0');
 483                         break;
 484                 /* htonX are macros in older libc's, using temp var
 485                  * in code below for safety */
 486                 /* TODO: use bb_strtoX? */
 487                 case OPTION_U16: {
 488                         unsigned long tmp = strtoul(val, &endptr, 0);
 489                         *result_u16 = htons(tmp);
 490                         retval = (endptr[0] == '\0' /*&& tmp < 0x10000*/);
 491                         break;
 492                 }
 493 //              case OPTION_S16: {
 494 //                      long tmp = strtol(val, &endptr, 0);
 495 //                      *result_u16 = htons(tmp);
 496 //                      retval = (endptr[0] == '\0');
 497 //                      break;
 498 //              }
 499                 case OPTION_U32: {
 500                         unsigned long tmp = strtoul(val, &endptr, 0);
 501                         *result_u32 = htonl(tmp);
 502                         retval = (endptr[0] == '\0');
 503                         break;
 504                 }
 505                 case OPTION_S32: {
 506                         long tmp = strtol(val, &endptr, 0);
 507                         *result_u32 = htonl(tmp);
 508                         retval = (endptr[0] == '\0');
 509                         break;
 510                 }
 511                 case OPTION_BIN: /* handled in attach_option() */
 512                         opt = val;
 513                         retval = 1;
 514                 default:
 515                         break;
 516                 }
 517                 if (retval)
 518                         attach_option(opt_list, optflag, opt, length);
 519         } while (retval && optflag->flags & OPTION_LIST);
 520
 521         return retval;
 522 }