release/src/router/busybox/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 source tree.
   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        | OPTION_REQ, 0x79 }, /* DHCP_STATIC_ROUTES */
  57         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x21 }, /* DHCP_ROUTES        */
  58         { OPTION_STATIC_ROUTES        | OPTION_REQ, 0xf9 }, /* DHCP_MS_STATIC_ROUTES */
  59 #if ENABLE_FEATURE_UDHCP_RFC5969
  60         { OPTION_6RD                              , 0xd4 }, /* DHCP_6RD           */
  61         { OPTION_6RD                              , 0x96 }, /* DHCP_COMCAST_6RD   */
  62 #endif
  63         { OPTION_STRING                           , 0xfc }, /* DHCP_WPAD          */
  64
  65         /* Options below have no match in dhcp_option_strings[],
  66          * are not passed to dhcpc scripts, and cannot be specified
  67          * with "option XXX YYY" syntax in dhcpd config file.
  68          * These entries are only used internally by udhcp[cd]
  69          * to correctly encode options into packets.
  70          */
  71
  72         { OPTION_IP                               , 0x32 }, /* DHCP_REQUESTED_IP  */
  73         { OPTION_U8                               , 0x35 }, /* DHCP_MESSAGE_TYPE  */
  74         { OPTION_U16                              , 0x39 }, /* DHCP_MAX_SIZE      */
  75 //looks like these opts will work just fine even without these defs:
  76 //      { OPTION_STRING                           , 0x3c }, /* DHCP_VENDOR        */
  77 //      /* not really a string: */
  78 //      { OPTION_STRING                           , 0x3d }, /* DHCP_CLIENT_ID     */
  79         { 0, 0 } /* zeroed terminating entry */
  80 };
  81
  82 /* Used for converting options from incoming packets to env variables
  83  * for udhcpc stript, and for setting options for udhcpd via
  84  * "opt OPTION_NAME OPTION_VALUE" directives in udhcpd.conf file.
  85  */
  86 /* Must match dhcp_optflags[] order */
  87 const char dhcp_option_strings[] ALIGN1 =
  88         "subnet" "\0"      /* DHCP_SUBNET         */
  89         "timezone" "\0"    /* DHCP_TIME_OFFSET    */
  90         "router" "\0"      /* DHCP_ROUTER         */
  91 //      "timesrv" "\0"     /* DHCP_TIME_SERVER    */
  92 //      "namesrv" "\0"     /* DHCP_NAME_SERVER    */
  93         "dns" "\0"         /* DHCP_DNS_SERVER     */
  94 //      "logsrv" "\0"      /* DHCP_LOG_SERVER     */
  95 //      "cookiesrv" "\0"   /* DHCP_COOKIE_SERVER  */
  96         "lprsrv" "\0"      /* DHCP_LPR_SERVER     */
  97         "hostname" "\0"    /* DHCP_HOST_NAME      */
  98         "bootsize" "\0"    /* DHCP_BOOT_SIZE      */
  99         "domain" "\0"      /* DHCP_DOMAIN_NAME    */
 100         "swapsrv" "\0"     /* DHCP_SWAP_SERVER    */
 101         "rootpath" "\0"    /* DHCP_ROOT_PATH      */
 102         "ipttl" "\0"       /* DHCP_IP_TTL         */
 103         "mtu" "\0"         /* DHCP_MTU            */
 104         "broadcast" "\0"   /* DHCP_BROADCAST      */
 105         "nisdomain" "\0"   /* DHCP_NIS_DOMAIN     */
 106         "nissrv" "\0"      /* DHCP_NIS_SERVER     */
 107         "ntpsrv" "\0"      /* DHCP_NTP_SERVER     */
 108         "wins" "\0"        /* DHCP_WINS_SERVER    */
 109         "lease" "\0"       /* DHCP_LEASE_TIME     */
 110         "serverid" "\0"    /* DHCP_SERVER_ID      */
 111         "message" "\0"     /* DHCP_ERR_MESSAGE    */
 112         "tftp" "\0"        /* DHCP_TFTP_SERVER_NAME */
 113         "bootfile" "\0"    /* DHCP_BOOT_FILE      */
 114 //      "userclass" "\0"   /* DHCP_USER_CLASS     */
 115 #if ENABLE_FEATURE_UDHCP_RFC3397
 116         "search" "\0"      /* DHCP_DOMAIN_SEARCH  */
 117 // doesn't work in udhcpd.conf since OPTION_SIP_SERVERS
 118 // is not handled yet by "string->option" conversion code:
 119         "sipsrv" "\0"      /* DHCP_SIP_SERVERS    */
 120 #endif
 121 // doesn't work in udhcpd.conf since OPTION_STATIC_ROUTES
 122 // is not handled yet by "string->option" conversion code:
 123         "staticroutes" "\0"/* DHCP_STATIC_ROUTES  */
 124         "routes" "\0"      /* DHCP_ROUTES         */
 125         "msstaticroutes""\0"/* DHCP_MS_STATIC_ROUTES */
 126 #if ENABLE_FEATURE_UDHCP_RFC5969
 127         "6rd" "\0"         /* DHCP_6RD            */
 128         "comcast6rd" "\0"  /* DHCP_COMCAST_6RD    */
 129 #endif
 130         "wpad" "\0"        /* DHCP_WPAD           */
 131         ;
 132
 133 /* Lengths of the option types in binary form.
 134  * Used by:
 135  * udhcp_str2optset: to determine how many bytes to allocate.
 136  * xmalloc_optname_optval: to estimate string length
 137  * from binary option length: (option[LEN] / dhcp_option_lengths[opt_type])
 138  * is the number of elements, multiply in by one element's string width
 139  * (len_of_option_as_string[opt_type]) and you know how wide string you need.
 140  */
 141 const uint8_t dhcp_option_lengths[] ALIGN1 = {
 142         [OPTION_IP] =      4,
 143         [OPTION_IP_PAIR] = 8,
 144 //      [OPTION_BOOLEAN] = 1,
 145         [OPTION_STRING] =  1,  /* ignored by udhcp_str2optset */
 146 #if ENABLE_FEATURE_UDHCP_RFC3397
 147         [OPTION_DNS_STRING] = 1,  /* ignored by both udhcp_str2optset and xmalloc_optname_optval */
 148         [OPTION_SIP_SERVERS] = 1,
 149 #endif
 150         [OPTION_U8] =      1,
 151         [OPTION_U16] =     2,
 152 //      [OPTION_S16] =     2,
 153         [OPTION_U32] =     4,
 154         [OPTION_S32] =     4,
 155         /* Just like OPTION_STRING, we use minimum length here */
 156         [OPTION_STATIC_ROUTES] = 5,
 157 #if ENABLE_FEATURE_UDHCP_RFC5969
 158         [OPTION_6RD] =    22,
 159 #endif
 160 };
 161
 162
 163 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 2
 164 static void log_option(const char *pfx, const uint8_t *opt)
 165 {
 166         if (dhcp_verbose >= 2) {
 167                 char buf[256 * 2 + 2];
 168                 *bin2hex(buf, (void*) (opt + OPT_DATA), opt[OPT_LEN]) = '\0';
 169                 bb_info_msg("%s: 0x%02x %s", pfx, opt[OPT_CODE], buf);
 170         }
 171 }
 172 #else
 173 # define log_option(pfx, opt) ((void)0)
 174 #endif
 175
 176 unsigned FAST_FUNC udhcp_option_idx(const char *name)
 177 {
 178         int n = index_in_strings(dhcp_option_strings, name);
 179         if (n >= 0)
 180                 return n;
 181
 182         {
 183                 char buf[sizeof(dhcp_option_strings)];
 184                 char *d = buf;
 185                 const char *s = dhcp_option_strings;
 186                 while (s < dhcp_option_strings + sizeof(dhcp_option_strings) - 2) {
 187                         *d++ = (*s == '\0' ? ' ' : *s);
 188                         s++;
 189                 }
 190                 *d = '\0';
 191                 bb_error_msg_and_die("unknown option '%s', known options: %s", name, buf);
 192         }
 193 }
 194
 195 /* Get an option with bounds checking (warning, result is not aligned) */
 196 uint8_t* FAST_FUNC udhcp_get_option(struct dhcp_packet *packet, int code)
 197 {
 198         uint8_t *optionptr;
 199         int len;
 200         int rem;
 201         int overload = 0;
 202         enum {
 203                 FILE_FIELD101  = FILE_FIELD  * 0x101,
 204                 SNAME_FIELD101 = SNAME_FIELD * 0x101,
 205         };
 206
 207         /* option bytes: [code][len][data1][data2]..[dataLEN] */
 208         optionptr = packet->options;
 209         rem = sizeof(packet->options);
 210         while (1) {
 211                 if (rem <= 0) {
 212                         bb_error_msg("bad packet, malformed option field");
 213                         return NULL;
 214                 }
 215                 if (optionptr[OPT_CODE] == DHCP_PADDING) {
 216                         rem--;
 217                         optionptr++;
 218                         continue;
 219                 }
 220                 if (optionptr[OPT_CODE] == DHCP_END) {
 221                         if ((overload & FILE_FIELD101) == FILE_FIELD) {
 222                                 /* can use packet->file, and didn't look at it yet */
 223                                 overload |= FILE_FIELD101; /* "we looked at it" */
 224                                 optionptr = packet->file;
 225                                 rem = sizeof(packet->file);
 226                                 continue;
 227                         }
 228                         if ((overload & SNAME_FIELD101) == SNAME_FIELD) {
 229                                 /* can use packet->sname, and didn't look at it yet */
 230                                 overload |= SNAME_FIELD101; /* "we looked at it" */
 231                                 optionptr = packet->sname;
 232                                 rem = sizeof(packet->sname);
 233                                 continue;
 234                         }
 235                         break;
 236                 }
 237                 len = 2 + optionptr[OPT_LEN];
 238                 rem -= len;
 239                 if (rem < 0)
 240                         continue; /* complain and return NULL */
 241
 242                 if (optionptr[OPT_CODE] == code) {
 243                         log_option("Option found", optionptr);
 244                         return optionptr + OPT_DATA;
 245                 }
 246
 247                 if (optionptr[OPT_CODE] == DHCP_OPTION_OVERLOAD) {
 248                         overload |= optionptr[OPT_DATA];
 249                         /* fall through */
 250                 }
 251                 optionptr += len;
 252         }
 253
 254         /* log3 because udhcpc uses it a lot - very noisy */
 255         log3("Option 0x%02x not found", code);
 256         return NULL;
 257 }
 258
 259 /* Return the position of the 'end' option (no bounds checking) */
 260 int FAST_FUNC udhcp_end_option(uint8_t *optionptr)
 261 {
 262         int i = 0;
 263
 264         while (optionptr[i] != DHCP_END) {
 265                 if (optionptr[i] != DHCP_PADDING)
 266                         i += optionptr[i + OPT_LEN] + OPT_DATA-1;
 267                 i++;
 268         }
 269         return i;
 270 }
 271
 272 /* Add an option (supplied in binary form) to the options.
 273  * Option format: [code][len][data1][data2]..[dataLEN]
 274  */
 275 void FAST_FUNC udhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt)
 276 {
 277         unsigned len;
 278         uint8_t *optionptr = packet->options;
 279         unsigned end = udhcp_end_option(optionptr);
 280
 281         len = OPT_DATA + addopt[OPT_LEN];
 282         /* end position + (option code/length + addopt length) + end option */
 283         if (end + len + 1 >= DHCP_OPTIONS_BUFSIZE) {
 284 //TODO: learn how to use overflow option if we exhaust packet->options[]
 285                 bb_error_msg("option 0x%02x did not fit into the packet",
 286                                 addopt[OPT_CODE]);
 287                 return;
 288         }
 289         log_option("Adding option", addopt);
 290         memcpy(optionptr + end, addopt, len);
 291         optionptr[end + len] = DHCP_END;
 292 }
 293
 294 /* Add an one to four byte option to a packet */
 295 void FAST_FUNC udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, uint32_t data)
 296 {
 297         const struct dhcp_optflag *dh;
 298
 299         for (dh = dhcp_optflags; dh->code; dh++) {
 300                 if (dh->code == code) {
 301                         uint8_t option[6], len;
 302
 303                         option[OPT_CODE] = code;
 304                         len = dhcp_option_lengths[dh->flags & OPTION_TYPE_MASK];
 305                         option[OPT_LEN] = len;
 306                         if (BB_BIG_ENDIAN)
 307                                 data <<= 8 * (4 - len);
 308                         /* Assignment is unaligned! */
 309                         move_to_unaligned32(&option[OPT_DATA], data);
 310                         udhcp_add_binary_option(packet, option);
 311                         return;
 312                 }
 313         }
 314
 315         bb_error_msg("can't add option 0x%02x", code);
 316 }
 317
 318 /* Find option 'code' in opt_list */
 319 struct option_set* FAST_FUNC udhcp_find_option(struct option_set *opt_list, uint8_t code)
 320 {
 321         while (opt_list && opt_list->data[OPT_CODE] < code)
 322                 opt_list = opt_list->next;
 323
 324         if (opt_list && opt_list->data[OPT_CODE] == code)
 325                 return opt_list;
 326         return NULL;
 327 }
 328
 329 /* Parse string to IP in network order */
 330 int FAST_FUNC udhcp_str2nip(const char *str, void *arg)
 331 {
 332         len_and_sockaddr *lsa;
 333
 334         lsa = host_and_af2sockaddr(str, 0, AF_INET);
 335         if (!lsa)
 336                 return 0;
 337         *(uint32_t*)arg = lsa->u.sin.sin_addr.s_addr;
 338         free(lsa);
 339         return 1;
 340 }
 341
 342 /* udhcp_str2optset:
 343  * Parse string option representation to binary form and add it to opt_list.
 344  * Called to parse "udhcpc -x OPTNAME:OPTVAL"
 345  * and to parse udhcpd.conf's "opt OPTNAME OPTVAL" directives.
 346  */
 347 /* helper for the helper */
 348 static char *allocate_tempopt_if_needed(
 349                 const struct dhcp_optflag *optflag,
 350                 char *buffer,
 351                 int *length_p)
 352 {
 353         char *allocated = NULL;
 354         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_BIN) {
 355                 const char *end;
 356                 allocated = xstrdup(buffer); /* more than enough */
 357                 end = hex2bin(allocated, buffer, 255);
 358                 if (errno)
 359                         bb_error_msg_and_die("malformed hex string '%s'", buffer);
 360                 *length_p = end - allocated;
 361         }
 362         return allocated;
 363 }
 364 /* helper: add an option to the opt_list */
 365 static NOINLINE void attach_option(
 366                 struct option_set **opt_list,
 367                 const struct dhcp_optflag *optflag,
 368                 char *buffer,
 369                 int length)
 370 {
 371         struct option_set *existing, *new, **curr;
 372         char *allocated = NULL;
 373
 374         existing = udhcp_find_option(*opt_list, optflag->code);
 375         if (!existing) {
 376                 log2("Attaching option %02x to list", optflag->code);
 377                 allocated = allocate_tempopt_if_needed(optflag, buffer, &length);
 378 #if ENABLE_FEATURE_UDHCP_RFC3397
 379                 if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_DNS_STRING) {
 380                         /* reuse buffer and length for RFC1035-formatted string */
 381                         allocated = buffer = (char *)dname_enc(NULL, 0, buffer, &length);
 382                 }
 383 #endif
 384                 /* make a new option */
 385                 new = xmalloc(sizeof(*new));
 386                 new->data = xmalloc(length + OPT_DATA);
 387                 new->data[OPT_CODE] = optflag->code;
 388                 new->data[OPT_LEN] = length;
 389                 memcpy(new->data + OPT_DATA, (allocated ? allocated : buffer), length);
 390
 391                 curr = opt_list;
 392                 while (*curr && (*curr)->data[OPT_CODE] < optflag->code)
 393                         curr = &(*curr)->next;
 394
 395                 new->next = *curr;
 396                 *curr = new;
 397                 goto ret;
 398         }
 399
 400         if (optflag->flags & OPTION_LIST) {
 401                 unsigned old_len;
 402
 403                 /* add it to an existing option */
 404                 log2("Attaching option %02x to existing member of list", optflag->code);
 405                 allocated = allocate_tempopt_if_needed(optflag, buffer, &length);
 406                 old_len = existing->data[OPT_LEN];
 407 #if ENABLE_FEATURE_UDHCP_RFC3397
 408                 if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_DNS_STRING) {
 409                         /* reuse buffer and length for RFC1035-formatted string */
 410                         allocated = buffer = (char *)dname_enc(existing->data + OPT_DATA, old_len, buffer, &length);
 411                 }
 412 #endif
 413                 if (old_len + length < 255) {
 414                         /* actually 255 is ok too, but adding a space can overlow it */
 415
 416                         existing->data = xrealloc(existing->data, OPT_DATA + 1 + old_len + length);
 417                         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING) {
 418                                 /* add space separator between STRING options in a list */
 419                                 existing->data[OPT_DATA + old_len] = ' ';
 420                                 old_len++;
 421                         }
 422                         memcpy(existing->data + OPT_DATA + old_len, buffer, length);
 423                         existing->data[OPT_LEN] = old_len + length;
 424                 } /* else, ignore the data, we could put this in a second option in the future */
 425         } /* else, ignore the new data */
 426
 427  ret:
 428         free(allocated);
 429 }
 430
 431 int FAST_FUNC udhcp_str2optset(const char *const_str, void *arg)
 432 {
 433         struct option_set **opt_list = arg;
 434         char *opt, *val, *endptr;
 435         char *str;
 436         const struct dhcp_optflag *optflag;
 437         struct dhcp_optflag bin_optflag;
 438         unsigned optcode;
 439         int retval, length;
 440         char buffer[8] ALIGNED(4);
 441         uint16_t *result_u16 = (uint16_t *) buffer;
 442         uint32_t *result_u32 = (uint32_t *) buffer;
 443
 444         /* Cheat, the only *const* str possible is "" */
 445         str = (char *) const_str;
 446         opt = strtok(str, " \t=");
 447         if (!opt)
 448                 return 0;
 449
 450         optcode = bb_strtou(opt, NULL, 0);
 451         if (!errno && optcode < 255) {
 452                 /* Raw (numeric) option code */
 453                 bin_optflag.flags = OPTION_BIN;
 454                 bin_optflag.code = optcode;
 455                 optflag = &bin_optflag;
 456         } else {
 457                 optflag = &dhcp_optflags[udhcp_option_idx(opt)];
 458         }
 459
 460         retval = 0;
 461         do {
 462                 val = strtok(NULL, ", \t");
 463                 if (!val)
 464                         break;
 465                 length = dhcp_option_lengths[optflag->flags & OPTION_TYPE_MASK];
 466                 retval = 0;
 467                 opt = buffer; /* new meaning for variable opt */
 468                 switch (optflag->flags & OPTION_TYPE_MASK) {
 469                 case OPTION_IP:
 470                         retval = udhcp_str2nip(val, buffer);
 471                         break;
 472                 case OPTION_IP_PAIR:
 473                         retval = udhcp_str2nip(val, buffer);
 474                         val = strtok(NULL, ", \t/-");
 475                         if (!val)
 476                                 retval = 0;
 477                         if (retval)
 478                                 retval = udhcp_str2nip(val, buffer + 4);
 479                         break;
 480                 case OPTION_STRING:
 481 #if ENABLE_FEATURE_UDHCP_RFC3397
 482                 case OPTION_DNS_STRING:
 483 #endif
 484                         length = strnlen(val, 254);
 485                         if (length > 0) {
 486                                 opt = val;
 487                                 retval = 1;
 488                         }
 489                         break;
 490 //              case OPTION_BOOLEAN: {
 491 //                      static const char no_yes[] ALIGN1 = "no\0yes\0";
 492 //                      buffer[0] = retval = index_in_strings(no_yes, val);
 493 //                      retval++; /* 0 - bad; 1: "no" 2: "yes" */
 494 //                      break;
 495 //              }
 496                 case OPTION_U8:
 497                         buffer[0] = strtoul(val, &endptr, 0);
 498                         retval = (endptr[0] == '\0');
 499                         break;
 500                 /* htonX are macros in older libc's, using temp var
 501                  * in code below for safety */
 502                 /* TODO: use bb_strtoX? */
 503                 case OPTION_U16: {
 504                         unsigned long tmp = strtoul(val, &endptr, 0);
 505                         *result_u16 = htons(tmp);
 506                         retval = (endptr[0] == '\0' /*&& tmp < 0x10000*/);
 507                         break;
 508                 }
 509 //              case OPTION_S16: {
 510 //                      long tmp = strtol(val, &endptr, 0);
 511 //                      *result_u16 = htons(tmp);
 512 //                      retval = (endptr[0] == '\0');
 513 //                      break;
 514 //              }
 515                 case OPTION_U32: {
 516                         unsigned long tmp = strtoul(val, &endptr, 0);
 517                         *result_u32 = htonl(tmp);
 518                         retval = (endptr[0] == '\0');
 519                         break;
 520                 }
 521                 case OPTION_S32: {
 522                         long tmp = strtol(val, &endptr, 0);
 523                         *result_u32 = htonl(tmp);
 524                         retval = (endptr[0] == '\0');
 525                         break;
 526                 }
 527                 case OPTION_BIN: /* handled in attach_option() */
 528                         opt = val;
 529                         retval = 1;
 530                 default:
 531                         break;
 532                 }
 533                 if (retval)
 534                         attach_option(opt_list, optflag, opt, length);
 535         } while (retval && optflag->flags & OPTION_LIST);
 536
 537         return retval;
 538 }