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_HOST          | OPTION_REQ, 0x0c }, /* DHCP_HOST_NAME     */
  33         { OPTION_U16                              , 0x0d }, /* DHCP_BOOT_SIZE     */
  34         { OPTION_STRING_HOST          | 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 //TODO: why do we request DHCP_BROADCAST? Can't we assume that
  40 //in the unlikely case it is different from typical N.N.255.255,
  41 //server would let us know anyway?
  42         { OPTION_IP                   | OPTION_REQ, 0x1c }, /* DHCP_BROADCAST     */
  43         { OPTION_IP_PAIR | OPTION_LIST            , 0x21 }, /* DHCP_ROUTES        */
  44         { OPTION_STRING_HOST                      , 0x28 }, /* DHCP_NIS_DOMAIN    */
  45         { OPTION_IP | OPTION_LIST                 , 0x29 }, /* DHCP_NIS_SERVER    */
  46         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x2a }, /* DHCP_NTP_SERVER    */
  47         { OPTION_IP | OPTION_LIST                 , 0x2c }, /* DHCP_WINS_SERVER   */
  48         { OPTION_U32                              , 0x33 }, /* DHCP_LEASE_TIME    */
  49         { OPTION_IP                               , 0x36 }, /* DHCP_SERVER_ID     */
  50         { OPTION_STRING                           , 0x38 }, /* DHCP_ERR_MESSAGE   */
  51 //TODO: must be combined with 'sname' and 'file' handling:
  52         { OPTION_STRING_HOST                      , 0x42 }, /* DHCP_TFTP_SERVER_NAME */
  53         { OPTION_STRING                           , 0x43 }, /* DHCP_BOOT_FILE     */
  54 //TODO: not a string, but a set of LASCII strings:
  55 //      { OPTION_STRING                           , 0x4D }, /* DHCP_USER_CLASS    */
  56 #if ENABLE_FEATURE_UDHCP_RFC3397
  57         { OPTION_DNS_STRING | OPTION_LIST         , 0x77 }, /* DHCP_DOMAIN_SEARCH */
  58         { OPTION_SIP_SERVERS                      , 0x78 }, /* DHCP_SIP_SERVERS   */
  59 #endif
  60         { OPTION_STATIC_ROUTES | OPTION_LIST      , 0x79 }, /* DHCP_STATIC_ROUTES */
  61 #if ENABLE_FEATURE_UDHCP_8021Q
  62         { OPTION_U16                              , 0x84 }, /* DHCP_VLAN_ID       */
  63         { OPTION_U8                               , 0x85 }, /* DHCP_VLAN_PRIORITY */
  64 #endif
  65         { OPTION_STRING                           , 0xd1 }, /* DHCP_PXE_CONF_FILE */
  66         { OPTION_STRING                           , 0xd2 }, /* DHCP_PXE_PATH_PREFIX */
  67         { OPTION_6RD                              , 0xd4 }, /* DHCP_6RD           */
  68         { OPTION_STATIC_ROUTES | OPTION_LIST      , 0xf9 }, /* DHCP_MS_STATIC_ROUTES */
  69         { OPTION_STRING                           , 0xfc }, /* DHCP_WPAD          */
  70
  71         /* Options below have no match in dhcp_option_strings[],
  72          * are not passed to dhcpc scripts, and cannot be specified
  73          * with "option XXX YYY" syntax in dhcpd config file.
  74          * These entries are only used internally by udhcp[cd]
  75          * to correctly encode options into packets.
  76          */
  77
  78         { OPTION_IP                               , 0x32 }, /* DHCP_REQUESTED_IP  */
  79         { OPTION_U8                               , 0x35 }, /* DHCP_MESSAGE_TYPE  */
  80         { OPTION_U16                              , 0x39 }, /* DHCP_MAX_SIZE      */
  81 //looks like these opts will work just fine even without these defs:
  82 //      { OPTION_STRING                           , 0x3c }, /* DHCP_VENDOR        */
  83 //      /* not really a string: */
  84 //      { OPTION_STRING                           , 0x3d }, /* DHCP_CLIENT_ID     */
  85         { 0, 0 } /* zeroed terminating entry */
  86 };
  87
  88 /* Used for converting options from incoming packets to env variables
  89  * for udhcpc script, and for setting options for udhcpd via
  90  * "opt OPTION_NAME OPTION_VALUE" directives in udhcpd.conf file.
  91  */
  92 /* Must match dhcp_optflags[] order */
  93 const char dhcp_option_strings[] ALIGN1 =
  94         "subnet" "\0"      /* DHCP_SUBNET         */
  95         "timezone" "\0"    /* DHCP_TIME_OFFSET    */
  96         "router" "\0"      /* DHCP_ROUTER         */
  97 //      "timesrv" "\0"     /* DHCP_TIME_SERVER    */
  98 //      "namesrv" "\0"     /* DHCP_NAME_SERVER    */
  99         "dns" "\0"         /* DHCP_DNS_SERVER     */
 100 //      "logsrv" "\0"      /* DHCP_LOG_SERVER     */
 101 //      "cookiesrv" "\0"   /* DHCP_COOKIE_SERVER  */
 102         "lprsrv" "\0"      /* DHCP_LPR_SERVER     */
 103         "hostname" "\0"    /* DHCP_HOST_NAME      */
 104         "bootsize" "\0"    /* DHCP_BOOT_SIZE      */
 105         "domain" "\0"      /* DHCP_DOMAIN_NAME    */
 106         "swapsrv" "\0"     /* DHCP_SWAP_SERVER    */
 107         "rootpath" "\0"    /* DHCP_ROOT_PATH      */
 108         "ipttl" "\0"       /* DHCP_IP_TTL         */
 109         "mtu" "\0"         /* DHCP_MTU            */
 110         "broadcast" "\0"   /* DHCP_BROADCAST      */
 111         "routes" "\0"      /* DHCP_ROUTES         */
 112         "nisdomain" "\0"   /* DHCP_NIS_DOMAIN     */
 113         "nissrv" "\0"      /* DHCP_NIS_SERVER     */
 114         "ntpsrv" "\0"      /* DHCP_NTP_SERVER     */
 115         "wins" "\0"        /* DHCP_WINS_SERVER    */
 116         "lease" "\0"       /* DHCP_LEASE_TIME     */
 117         "serverid" "\0"    /* DHCP_SERVER_ID      */
 118         "message" "\0"     /* DHCP_ERR_MESSAGE    */
 119         "tftp" "\0"        /* DHCP_TFTP_SERVER_NAME */
 120         "bootfile" "\0"    /* DHCP_BOOT_FILE      */
 121 //      "userclass" "\0"   /* DHCP_USER_CLASS     */
 122 #if ENABLE_FEATURE_UDHCP_RFC3397
 123         "search" "\0"      /* DHCP_DOMAIN_SEARCH  */
 124 // doesn't work in udhcpd.conf since OPTION_SIP_SERVERS
 125 // is not handled yet by "string->option" conversion code:
 126         "sipsrv" "\0"      /* DHCP_SIP_SERVERS    */
 127 #endif
 128         "staticroutes" "\0"/* DHCP_STATIC_ROUTES  */
 129 #if ENABLE_FEATURE_UDHCP_8021Q
 130         "vlanid" "\0"      /* DHCP_VLAN_ID        */
 131         "vlanpriority" "\0"/* DHCP_VLAN_PRIORITY  */
 132 #endif
 133         "pxeconffile" "\0" /* DHCP_PXE_CONF_FILE  */
 134         "pxepathprefix" "\0" /* DHCP_PXE_PATH_PREFIX  */
 135         "ip6rd" "\0"       /* DHCP_6RD            */
 136         "msstaticroutes""\0"/* DHCP_MS_STATIC_ROUTES */
 137         "wpad" "\0"        /* DHCP_WPAD           */
 138         ;
 139
 140 /* Lengths of the option types in binary form.
 141  * Used by:
 142  * udhcp_str2optset: to determine how many bytes to allocate.
 143  * xmalloc_optname_optval: to estimate string length
 144  * from binary option length: (option[LEN] / dhcp_option_lengths[opt_type])
 145  * is the number of elements, multiply it by one element's string width
 146  * (len_of_option_as_string[opt_type]) and you know how wide string you need.
 147  */
 148 const uint8_t dhcp_option_lengths[] ALIGN1 = {
 149         [OPTION_IP] =      4,
 150         [OPTION_IP_PAIR] = 8,
 151 //      [OPTION_BOOLEAN] = 1,
 152         [OPTION_STRING] =  1,  /* ignored by udhcp_str2optset */
 153         [OPTION_STRING_HOST] = 1,  /* ignored by udhcp_str2optset */
 154 #if ENABLE_FEATURE_UDHCP_RFC3397
 155         [OPTION_DNS_STRING] = 1,  /* ignored by both udhcp_str2optset and xmalloc_optname_optval */
 156         [OPTION_SIP_SERVERS] = 1,
 157 #endif
 158         [OPTION_U8] =      1,
 159         [OPTION_U16] =     2,
 160 //      [OPTION_S16] =     2,
 161         [OPTION_U32] =     4,
 162         [OPTION_S32] =     4,
 163         /* Just like OPTION_STRING, we use minimum length here */
 164         [OPTION_STATIC_ROUTES] = 5,
 165         [OPTION_6RD] =    12,  /* ignored by udhcp_str2optset */
 166         /* The above value was chosen as follows:
 167          * len_of_option_as_string[] for this option is >60: it's a string of the form
 168          * "32 128 ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff 255.255.255.255 ".
 169          * Each additional ipv4 address takes 4 bytes in binary option and appends
 170          * another "255.255.255.255 " 16-byte string. We can set [OPTION_6RD] = 4
 171          * but this severely overestimates string length: instead of 16 bytes,
 172          * it adds >60 for every 4 bytes in binary option.
 173          * We cheat and declare here that option is in units of 12 bytes.
 174          * This adds more than 60 bytes for every three ipv4 addresses - more than enough.
 175          * (Even 16 instead of 12 should work, but let's be paranoid).
 176          */
 177 };
 178
 179
 180 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 2
 181 static void log_option(const char *pfx, const uint8_t *opt)
 182 {
 183         if (dhcp_verbose >= 2) {
 184                 char buf[256 * 2 + 2];
 185                 *bin2hex(buf, (void*) (opt + OPT_DATA), opt[OPT_LEN]) = '\0';
 186                 bb_error_msg("%s: 0x%02x %s", pfx, opt[OPT_CODE], buf);
 187         }
 188 }
 189 #else
 190 # define log_option(pfx, opt) ((void)0)
 191 #endif
 192
 193 unsigned FAST_FUNC udhcp_option_idx(const char *name)
 194 {
 195         int n = index_in_strings(dhcp_option_strings, name);
 196         if (n >= 0)
 197                 return n;
 198
 199         {
 200                 char buf[sizeof(dhcp_option_strings)];
 201                 char *d = buf;
 202                 const char *s = dhcp_option_strings;
 203                 while (s < dhcp_option_strings + sizeof(dhcp_option_strings) - 2) {
 204                         *d++ = (*s == '\0' ? ' ' : *s);
 205                         s++;
 206                 }
 207                 *d = '\0';
 208                 bb_error_msg_and_die("unknown option '%s', known options: %s", name, buf);
 209         }
 210 }
 211
 212 /* Get an option with bounds checking (warning, result is not aligned) */
 213 uint8_t* FAST_FUNC udhcp_get_option(struct dhcp_packet *packet, int code)
 214 {
 215         uint8_t *optionptr;
 216         int len;
 217         int rem;
 218         int overload = 0;
 219         enum {
 220                 FILE_FIELD101  = FILE_FIELD  * 0x101,
 221                 SNAME_FIELD101 = SNAME_FIELD * 0x101,
 222         };
 223
 224         /* option bytes: [code][len][data1][data2]..[dataLEN] */
 225         optionptr = packet->options;
 226         rem = sizeof(packet->options);
 227         while (1) {
 228                 if (rem <= 0) {
 229  complain:
 230                         bb_error_msg("bad packet, malformed option field");
 231                         return NULL;
 232                 }
 233
 234                 /* DHCP_PADDING and DHCP_END have no [len] byte */
 235                 if (optionptr[OPT_CODE] == DHCP_PADDING) {
 236                         rem--;
 237                         optionptr++;
 238                         continue;
 239                 }
 240                 if (optionptr[OPT_CODE] == DHCP_END) {
 241                         if ((overload & FILE_FIELD101) == FILE_FIELD) {
 242                                 /* can use packet->file, and didn't look at it yet */
 243                                 overload |= FILE_FIELD101; /* "we looked at it" */
 244                                 optionptr = packet->file;
 245                                 rem = sizeof(packet->file);
 246                                 continue;
 247                         }
 248                         if ((overload & SNAME_FIELD101) == SNAME_FIELD) {
 249                                 /* can use packet->sname, and didn't look at it yet */
 250                                 overload |= SNAME_FIELD101; /* "we looked at it" */
 251                                 optionptr = packet->sname;
 252                                 rem = sizeof(packet->sname);
 253                                 continue;
 254                         }
 255                         break;
 256                 }
 257
 258                 if (rem <= OPT_LEN)
 259                         goto complain; /* complain and return NULL */
 260                 len = 2 + optionptr[OPT_LEN];
 261                 rem -= len;
 262                 if (rem < 0)
 263                         goto complain; /* complain and return NULL */
 264
 265                 if (optionptr[OPT_CODE] == code) {
 266                         log_option("option found", optionptr);
 267                         return optionptr + OPT_DATA;
 268                 }
 269
 270                 if (optionptr[OPT_CODE] == DHCP_OPTION_OVERLOAD) {
 271                         if (len >= 3)
 272                                 overload |= optionptr[OPT_DATA];
 273                         /* fall through */
 274                 }
 275                 optionptr += len;
 276         }
 277
 278         /* log3 because udhcpc uses it a lot - very noisy */
 279         log3("option 0x%02x not found", code);
 280         return NULL;
 281 }
 282
 283 /* Return the position of the 'end' option (no bounds checking) */
 284 int FAST_FUNC udhcp_end_option(uint8_t *optionptr)
 285 {
 286         int i = 0;
 287
 288         while (optionptr[i] != DHCP_END) {
 289                 if (optionptr[i] != DHCP_PADDING)
 290                         i += optionptr[i + OPT_LEN] + OPT_DATA-1;
 291                 i++;
 292         }
 293         return i;
 294 }
 295
 296 /* Add an option (supplied in binary form) to the options.
 297  * Option format: [code][len][data1][data2]..[dataLEN]
 298  */
 299 void FAST_FUNC udhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt)
 300 {
 301         unsigned len;
 302         uint8_t *optionptr = packet->options;
 303         unsigned end = udhcp_end_option(optionptr);
 304
 305         len = OPT_DATA + addopt[OPT_LEN];
 306         /* end position + (option code/length + addopt length) + end option */
 307         if (end + len + 1 >= DHCP_OPTIONS_BUFSIZE) {
 308 //TODO: learn how to use overflow option if we exhaust packet->options[]
 309                 bb_error_msg("option 0x%02x did not fit into the packet",
 310                                 addopt[OPT_CODE]);
 311                 return;
 312         }
 313         log_option("adding option", addopt);
 314         memcpy(optionptr + end, addopt, len);
 315         optionptr[end + len] = DHCP_END;
 316 }
 317
 318 /* Add an one to four byte option to a packet */
 319 void FAST_FUNC udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, uint32_t data)
 320 {
 321         const struct dhcp_optflag *dh;
 322
 323         for (dh = dhcp_optflags; dh->code; dh++) {
 324                 if (dh->code == code) {
 325                         uint8_t option[6], len;
 326
 327                         option[OPT_CODE] = code;
 328                         len = dhcp_option_lengths[dh->flags & OPTION_TYPE_MASK];
 329                         option[OPT_LEN] = len;
 330                         if (BB_BIG_ENDIAN)
 331                                 data <<= 8 * (4 - len);
 332                         /* Assignment is unaligned! */
 333                         move_to_unaligned32(&option[OPT_DATA], data);
 334                         udhcp_add_binary_option(packet, option);
 335                         return;
 336                 }
 337         }
 338
 339         bb_error_msg("can't add option 0x%02x", code);
 340 }
 341
 342 /* Find option 'code' in opt_list */
 343 struct option_set* FAST_FUNC udhcp_find_option(struct option_set *opt_list, uint8_t code)
 344 {
 345         while (opt_list && opt_list->data[OPT_CODE] < code)
 346                 opt_list = opt_list->next;
 347
 348         if (opt_list && opt_list->data[OPT_CODE] == code)
 349                 return opt_list;
 350         return NULL;
 351 }
 352
 353 /* Parse string to IP in network order */
 354 int FAST_FUNC udhcp_str2nip(const char *str, void *arg)
 355 {
 356         len_and_sockaddr *lsa;
 357
 358         lsa = host_and_af2sockaddr(str, 0, AF_INET);
 359         if (!lsa)
 360                 return 0;
 361         /* arg maybe unaligned */
 362         move_to_unaligned32((uint32_t*)arg, lsa->u.sin.sin_addr.s_addr);
 363         free(lsa);
 364         return 1;
 365 }
 366
 367 /* udhcp_str2optset:
 368  * Parse string option representation to binary form and add it to opt_list.
 369  * Called to parse "udhcpc -x OPTNAME:OPTVAL"
 370  * and to parse udhcpd.conf's "opt OPTNAME OPTVAL" directives.
 371  */
 372 /* helper for the helper */
 373 static char *allocate_tempopt_if_needed(
 374                 const struct dhcp_optflag *optflag,
 375                 char *buffer,
 376                 int *length_p)
 377 {
 378         char *allocated = NULL;
 379         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_BIN) {
 380                 const char *end;
 381                 allocated = xstrdup(buffer); /* more than enough */
 382                 end = hex2bin(allocated, buffer, 255);
 383                 if (errno)
 384                         bb_error_msg_and_die("malformed hex string '%s'", buffer);
 385                 *length_p = end - allocated;
 386         }
 387         return allocated;
 388 }
 389 /* helper: add an option to the opt_list */
 390 static NOINLINE void attach_option(
 391                 struct option_set **opt_list,
 392                 const struct dhcp_optflag *optflag,
 393                 char *buffer,
 394                 int length)
 395 {
 396         struct option_set *existing;
 397         char *allocated;
 398
 399         allocated = allocate_tempopt_if_needed(optflag, buffer, &length);
 400 #if ENABLE_FEATURE_UDHCP_RFC3397
 401         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_DNS_STRING) {
 402                 /* reuse buffer and length for RFC1035-formatted string */
 403                 allocated = buffer = (char *)dname_enc(NULL, 0, buffer, &length);
 404         }
 405 #endif
 406
 407         existing = udhcp_find_option(*opt_list, optflag->code);
 408         if (!existing) {
 409                 struct option_set *new, **curr;
 410
 411                 /* make a new option */
 412                 log2("attaching option %02x to list", optflag->code);
 413                 new = xmalloc(sizeof(*new));
 414                 new->data = xmalloc(length + OPT_DATA);
 415                 new->data[OPT_CODE] = optflag->code;
 416                 new->data[OPT_LEN] = length;
 417                 memcpy(new->data + OPT_DATA, (allocated ? allocated : buffer), length);
 418
 419                 curr = opt_list;
 420                 while (*curr && (*curr)->data[OPT_CODE] < optflag->code)
 421                         curr = &(*curr)->next;
 422
 423                 new->next = *curr;
 424                 *curr = new;
 425                 goto ret;
 426         }
 427
 428         if (optflag->flags & OPTION_LIST) {
 429                 unsigned old_len;
 430
 431                 /* add it to an existing option */
 432                 log2("attaching option %02x to existing member of list", optflag->code);
 433                 old_len = existing->data[OPT_LEN];
 434                 if (old_len + length < 255) {
 435                         /* actually 255 is ok too, but adding a space can overlow it */
 436
 437                         existing->data = xrealloc(existing->data, OPT_DATA + 1 + old_len + length);
 438                         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING
 439                          || (optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING_HOST
 440                         ) {
 441                                 /* add space separator between STRING options in a list */
 442                                 existing->data[OPT_DATA + old_len] = ' ';
 443                                 old_len++;
 444                         }
 445                         memcpy(existing->data + OPT_DATA + old_len, (allocated ? allocated : buffer), length);
 446                         existing->data[OPT_LEN] = old_len + length;
 447                 } /* else, ignore the data, we could put this in a second option in the future */
 448         } /* else, ignore the new data */
 449
 450  ret:
 451         free(allocated);
 452 }
 453
 454 int FAST_FUNC udhcp_str2optset(const char *const_str, void *arg)
 455 {
 456         struct option_set **opt_list = arg;
 457         char *opt, *val;
 458         char *str;
 459         const struct dhcp_optflag *optflag;
 460         struct dhcp_optflag bin_optflag;
 461         unsigned optcode;
 462         int retval, length;
 463         /* IP_PAIR needs 8 bytes, STATIC_ROUTES needs 9 max */
 464         char buffer[9] ALIGNED(4);
 465         uint16_t *result_u16 = (uint16_t *) buffer;
 466         uint32_t *result_u32 = (uint32_t *) buffer;
 467
 468         /* Cheat, the only *const* str possible is "" */
 469         str = (char *) const_str;
 470         opt = strtok(str, " \t=");
 471         if (!opt)
 472                 return 0;
 473
 474         optcode = bb_strtou(opt, NULL, 0);
 475         if (!errno && optcode < 255) {
 476                 /* Raw (numeric) option code */
 477                 bin_optflag.flags = OPTION_BIN;
 478                 bin_optflag.code = optcode;
 479                 optflag = &bin_optflag;
 480         } else {
 481                 optflag = &dhcp_optflags[udhcp_option_idx(opt)];
 482         }
 483
 484         retval = 0;
 485         do {
 486                 val = strtok(NULL, ", \t");
 487                 if (!val)
 488                         break;
 489                 length = dhcp_option_lengths[optflag->flags & OPTION_TYPE_MASK];
 490                 retval = 0;
 491                 opt = buffer; /* new meaning for variable opt */
 492                 switch (optflag->flags & OPTION_TYPE_MASK) {
 493                 case OPTION_IP:
 494                         retval = udhcp_str2nip(val, buffer);
 495                         break;
 496                 case OPTION_IP_PAIR:
 497                         retval = udhcp_str2nip(val, buffer);
 498                         val = strtok(NULL, ", \t/-");
 499                         if (!val)
 500                                 retval = 0;
 501                         if (retval)
 502                                 retval = udhcp_str2nip(val, buffer + 4);
 503                         break;
 504                 case OPTION_STRING:
 505                 case OPTION_STRING_HOST:
 506 #if ENABLE_FEATURE_UDHCP_RFC3397
 507                 case OPTION_DNS_STRING:
 508 #endif
 509                         length = strnlen(val, 254);
 510                         if (length > 0) {
 511                                 opt = val;
 512                                 retval = 1;
 513                         }
 514                         break;
 515 //              case OPTION_BOOLEAN: {
 516 //                      static const char no_yes[] ALIGN1 = "no\0yes\0";
 517 //                      buffer[0] = retval = index_in_strings(no_yes, val);
 518 //                      retval++; /* 0 - bad; 1: "no" 2: "yes" */
 519 //                      break;
 520 //              }
 521                 case OPTION_U8:
 522                         buffer[0] = bb_strtou32(val, NULL, 0);
 523                         retval = (errno == 0);
 524                         break;
 525                 /* htonX are macros in older libc's, using temp var
 526                  * in code below for safety */
 527                 /* TODO: use bb_strtoX? */
 528                 case OPTION_U16: {
 529                         uint32_t tmp = bb_strtou32(val, NULL, 0);
 530                         *result_u16 = htons(tmp);
 531                         retval = (errno == 0 /*&& tmp < 0x10000*/);
 532                         break;
 533                 }
 534 //              case OPTION_S16: {
 535 //                      long tmp = bb_strtoi32(val, NULL, 0);
 536 //                      *result_u16 = htons(tmp);
 537 //                      retval = (errno == 0);
 538 //                      break;
 539 //              }
 540                 case OPTION_U32: {
 541                         uint32_t tmp = bb_strtou32(val, NULL, 0);
 542                         *result_u32 = htonl(tmp);
 543                         retval = (errno == 0);
 544                         break;
 545                 }
 546                 case OPTION_S32: {
 547                         int32_t tmp = bb_strtoi32(val, NULL, 0);
 548                         *result_u32 = htonl(tmp);
 549                         retval = (errno == 0);
 550                         break;
 551                 }
 552                 case OPTION_STATIC_ROUTES: {
 553                         /* Input: "a.b.c.d/m" */
 554                         /* Output: mask(1 byte),pfx(0-4 bytes),gw(4 bytes) */
 555                         unsigned mask;
 556                         char *slash = strchr(val, '/');
 557                         if (slash) {
 558                                 *slash = '\0';
 559                                 retval = udhcp_str2nip(val, buffer + 1);
 560                                 buffer[0] = mask = bb_strtou(slash + 1, NULL, 10);
 561                                 val = strtok(NULL, ", \t/-");
 562                                 if (!val || mask > 32 || errno)
 563                                         retval = 0;
 564                                 if (retval) {
 565                                         length = ((mask + 7) >> 3) + 5;
 566                                         retval = udhcp_str2nip(val, buffer + (length - 4));
 567                                 }
 568                         }
 569                         break;
 570                 }
 571                 case OPTION_BIN: /* handled in attach_option() */
 572                         opt = val;
 573                         retval = 1;
 574                 default:
 575                         break;
 576                 }
 577                 if (retval)
 578                         attach_option(opt_list, optflag, opt, length);
 579         } while (retval && (optflag->flags & OPTION_LIST));
 580
 581         return retval;
 582 }
 583
 584 /* note: ip is a pointer to an IPv6 in network order, possibly misaliged */
 585 int FAST_FUNC sprint_nip6(char *dest, /*const char *pre,*/ const uint8_t *ip)
 586 {
 587         char hexstrbuf[16 * 2];
 588         bin2hex(hexstrbuf, (void*)ip, 16);
 589         return sprintf(dest, /* "%s" */
 590                 "%.4s:%.4s:%.4s:%.4s:%.4s:%.4s:%.4s:%.4s",
 591                 /* pre, */
 592                 hexstrbuf + 0 * 4,
 593                 hexstrbuf + 1 * 4,
 594                 hexstrbuf + 2 * 4,
 595                 hexstrbuf + 3 * 4,
 596                 hexstrbuf + 4 * 4,
 597                 hexstrbuf + 5 * 4,
 598                 hexstrbuf + 6 * 4,
 599                 hexstrbuf + 7 * 4
 600         );
 601 }