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 #if ENABLE_UDHCPC || ENABLE_UDHCPD
  18 /* Supported options are easily added here.
  19  * See RFC2132 for more options.
  20  * OPTION_REQ: these options are requested by udhcpc (unless -o).
  21  */
  22 const struct dhcp_optflag dhcp_optflags[] = {
  23         /* flags                                    code */
  24         { OPTION_IP                   | OPTION_REQ, 0x01 }, /* DHCP_SUBNET        */
  25         { OPTION_S32                              , 0x02 }, /* DHCP_TIME_OFFSET   */
  26         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x03 }, /* DHCP_ROUTER        */
  27 //      { OPTION_IP | OPTION_LIST                 , 0x04 }, /* DHCP_TIME_SERVER   */
  28 //      { OPTION_IP | OPTION_LIST                 , 0x05 }, /* DHCP_NAME_SERVER   */
  29         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x06 }, /* DHCP_DNS_SERVER    */
  30 //      { OPTION_IP | OPTION_LIST                 , 0x07 }, /* DHCP_LOG_SERVER    */
  31 //      { OPTION_IP | OPTION_LIST                 , 0x08 }, /* DHCP_COOKIE_SERVER */
  32         { OPTION_IP | OPTION_LIST                 , 0x09 }, /* DHCP_LPR_SERVER    */
  33         { OPTION_STRING_HOST          | OPTION_REQ, 0x0c }, /* DHCP_HOST_NAME     */
  34         { OPTION_U16                              , 0x0d }, /* DHCP_BOOT_SIZE     */
  35         { OPTION_STRING_HOST          | OPTION_REQ, 0x0f }, /* DHCP_DOMAIN_NAME   */
  36         { OPTION_IP                               , 0x10 }, /* DHCP_SWAP_SERVER   */
  37         { OPTION_STRING                           , 0x11 }, /* DHCP_ROOT_PATH     */
  38         { OPTION_U8                               , 0x17 }, /* DHCP_IP_TTL        */
  39         { OPTION_U16                              , 0x1a }, /* DHCP_MTU           */
  40 //TODO: why do we request DHCP_BROADCAST? Can't we assume that
  41 //in the unlikely case it is different from typical N.N.255.255,
  42 //server would let us know anyway?
  43         { OPTION_IP                   | OPTION_REQ, 0x1c }, /* DHCP_BROADCAST     */
  44         { OPTION_IP_PAIR | OPTION_LIST            , 0x21 }, /* DHCP_ROUTES        */
  45         { OPTION_STRING_HOST                      , 0x28 }, /* DHCP_NIS_DOMAIN    */
  46         { OPTION_IP | OPTION_LIST                 , 0x29 }, /* DHCP_NIS_SERVER    */
  47         { OPTION_IP | OPTION_LIST     | OPTION_REQ, 0x2a }, /* DHCP_NTP_SERVER    */
  48         { OPTION_IP | OPTION_LIST                 , 0x2c }, /* DHCP_WINS_SERVER   */
  49         { OPTION_U32                              , 0x33 }, /* DHCP_LEASE_TIME    */
  50         { OPTION_IP                               , 0x36 }, /* DHCP_SERVER_ID     */
  51         { OPTION_STRING                           , 0x38 }, /* DHCP_ERR_MESSAGE   */
  52 //TODO: must be combined with 'sname' and 'file' handling:
  53         { OPTION_STRING_HOST                      , 0x42 }, /* DHCP_TFTP_SERVER_NAME */
  54         { OPTION_STRING                           , 0x43 }, /* DHCP_BOOT_FILE     */
  55 //TODO: not a string, but a set of LASCII strings:
  56 //      { OPTION_STRING                           , 0x4D }, /* DHCP_USER_CLASS    */
  57         { OPTION_STRING                           , 0x64 }, /* DHCP_PCODE         */
  58         { OPTION_STRING                           , 0x65 }, /* DHCP_TCODE         */
  59 #if ENABLE_FEATURE_UDHCP_RFC3397
  60         { OPTION_DNS_STRING | OPTION_LIST         , 0x77 }, /* DHCP_DOMAIN_SEARCH */
  61         { OPTION_SIP_SERVERS                      , 0x78 }, /* DHCP_SIP_SERVERS   */
  62 #endif
  63         { OPTION_STATIC_ROUTES | OPTION_LIST      , 0x79 }, /* DHCP_STATIC_ROUTES */
  64 #if ENABLE_FEATURE_UDHCP_8021Q
  65         { OPTION_U16                              , 0x84 }, /* DHCP_VLAN_ID       */
  66         { OPTION_U8                               , 0x85 }, /* DHCP_VLAN_PRIORITY */
  67 #endif
  68         { OPTION_STRING                           , 0xd1 }, /* DHCP_PXE_CONF_FILE */
  69         { OPTION_STRING                           , 0xd2 }, /* DHCP_PXE_PATH_PREFIX */
  70         { OPTION_U32                              , 0xd3 }, /* DHCP_REBOOT_TIME   */
  71         { OPTION_6RD                              , 0xd4 }, /* DHCP_6RD           */
  72         { OPTION_STATIC_ROUTES | OPTION_LIST      , 0xf9 }, /* DHCP_MS_STATIC_ROUTES */
  73         { OPTION_STRING                           , 0xfc }, /* DHCP_WPAD          */
  74
  75         /* Options below have no match in dhcp_option_strings[],
  76          * are not passed to dhcpc scripts, and cannot be specified
  77          * with "option XXX YYY" syntax in dhcpd config file.
  78          * These entries are only used internally by udhcp[cd]
  79          * to correctly encode options into packets.
  80          */
  81
  82         { OPTION_IP                               , 0x32 }, /* DHCP_REQUESTED_IP  */
  83         { OPTION_U8                               , 0x35 }, /* DHCP_MESSAGE_TYPE  */
  84         { OPTION_U16                              , 0x39 }, /* DHCP_MAX_SIZE      */
  85 //looks like these opts will work just fine even without these defs:
  86 //      { OPTION_STRING                           , 0x3c }, /* DHCP_VENDOR        */
  87 //      /* not really a string: */
  88 //      { OPTION_STRING                           , 0x3d }, /* DHCP_CLIENT_ID     */
  89         { 0, 0 } /* zeroed terminating entry */
  90 };
  91
  92 /* Used for converting options from incoming packets to env variables
  93  * for udhcpc script, and for setting options for udhcpd via
  94  * "opt OPTION_NAME OPTION_VALUE" directives in udhcpd.conf file.
  95  */
  96 /* Must match dhcp_optflags[] order */
  97 const char dhcp_option_strings[] ALIGN1 =
  98         "subnet" "\0"           /* DHCP_SUBNET          */
  99         "timezone" "\0"         /* DHCP_TIME_OFFSET     */
 100         "router" "\0"           /* DHCP_ROUTER          */
 101 //      "timesrv" "\0"          /* DHCP_TIME_SERVER     */
 102 //      "namesrv" "\0"          /* DHCP_NAME_SERVER     */
 103         "dns" "\0"              /* DHCP_DNS_SERVER      */
 104 //      "logsrv" "\0"           /* DHCP_LOG_SERVER      */
 105 //      "cookiesrv" "\0"        /* DHCP_COOKIE_SERVER   */
 106         "lprsrv" "\0"           /* DHCP_LPR_SERVER      */
 107         "hostname" "\0"         /* DHCP_HOST_NAME       */
 108         "bootsize" "\0"         /* DHCP_BOOT_SIZE       */
 109         "domain" "\0"           /* DHCP_DOMAIN_NAME     */
 110         "swapsrv" "\0"          /* DHCP_SWAP_SERVER     */
 111         "rootpath" "\0"         /* DHCP_ROOT_PATH       */
 112         "ipttl" "\0"            /* DHCP_IP_TTL          */
 113         "mtu" "\0"              /* DHCP_MTU             */
 114         "broadcast" "\0"        /* DHCP_BROADCAST       */
 115         "routes" "\0"           /* DHCP_ROUTES          */
 116         "nisdomain" "\0"        /* DHCP_NIS_DOMAIN      */
 117         "nissrv" "\0"           /* DHCP_NIS_SERVER      */
 118         "ntpsrv" "\0"           /* DHCP_NTP_SERVER      */
 119         "wins" "\0"             /* DHCP_WINS_SERVER     */
 120         "lease" "\0"            /* DHCP_LEASE_TIME      */
 121         "serverid" "\0"         /* DHCP_SERVER_ID       */
 122         "message" "\0"          /* DHCP_ERR_MESSAGE     */
 123         "tftp" "\0"             /* DHCP_TFTP_SERVER_NAME*/
 124         "bootfile" "\0"         /* DHCP_BOOT_FILE       */
 125 //      "userclass" "\0"        /* DHCP_USER_CLASS      */
 126         "tzstr" "\0"            /* DHCP_PCODE           */
 127         "tzdbstr" "\0"          /* DHCP_TCODE           */
 128 #if ENABLE_FEATURE_UDHCP_RFC3397
 129         "search" "\0"           /* DHCP_DOMAIN_SEARCH   */
 130 // doesn't work in udhcpd.conf since OPTION_SIP_SERVERS
 131 // is not handled yet by "string->option" conversion code:
 132         "sipsrv" "\0"           /* DHCP_SIP_SERVERS     */
 133 #endif
 134         "staticroutes" "\0"     /* DHCP_STATIC_ROUTES   */
 135 #if ENABLE_FEATURE_UDHCP_8021Q
 136         "vlanid" "\0"           /* DHCP_VLAN_ID         */
 137         "vlanpriority" "\0"     /* DHCP_VLAN_PRIORITY   */
 138 #endif
 139         "pxeconffile" "\0"      /* DHCP_PXE_CONF_FILE   */
 140         "pxepathprefix" "\0"    /* DHCP_PXE_PATH_PREFIX */
 141         "reboottime" "\0"       /* DHCP_REBOOT_TIME     */
 142         "ip6rd" "\0"            /* DHCP_6RD             */
 143         "msstaticroutes" "\0"   /* DHCP_MS_STATIC_ROUTES*/
 144         "wpad" "\0"             /* DHCP_WPAD            */
 145         ;
 146 #endif
 147
 148 /* Lengths of the option types in binary form.
 149  * Used by:
 150  * udhcp_str2optset: to determine how many bytes to allocate.
 151  * xmalloc_optname_optval: to estimate string length
 152  * from binary option length: (option[LEN] / dhcp_option_lengths[opt_type])
 153  * is the number of elements, multiply it by one element's string width
 154  * (len_of_option_as_string[opt_type]) and you know how wide string you need.
 155  */
 156 const uint8_t dhcp_option_lengths[] ALIGN1 = {
 157         [OPTION_IP] =      4,
 158         [OPTION_IP_PAIR] = 8,
 159 //      [OPTION_BOOLEAN] = 1,
 160         [OPTION_STRING] =  1,  /* ignored by udhcp_str2optset */
 161         [OPTION_STRING_HOST] = 1,  /* ignored by udhcp_str2optset */
 162 #if ENABLE_FEATURE_UDHCP_RFC3397
 163         [OPTION_DNS_STRING] = 1,  /* ignored by both udhcp_str2optset and xmalloc_optname_optval */
 164         [OPTION_SIP_SERVERS] = 1,
 165 #endif
 166         [OPTION_U8] =      1,
 167         [OPTION_U16] =     2,
 168 //      [OPTION_S16] =     2,
 169         [OPTION_U32] =     4,
 170         [OPTION_S32] =     4,
 171         /* Just like OPTION_STRING, we use minimum length here */
 172         [OPTION_STATIC_ROUTES] = 5,
 173         [OPTION_6RD] =    12,  /* ignored by udhcp_str2optset */
 174         /* The above value was chosen as follows:
 175          * len_of_option_as_string[] for this option is >60: it's a string of the form
 176          * "32 128 ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff 255.255.255.255 ".
 177          * Each additional ipv4 address takes 4 bytes in binary option and appends
 178          * another "255.255.255.255 " 16-byte string. We can set [OPTION_6RD] = 4
 179          * but this severely overestimates string length: instead of 16 bytes,
 180          * it adds >60 for every 4 bytes in binary option.
 181          * We cheat and declare here that option is in units of 12 bytes.
 182          * This adds more than 60 bytes for every three ipv4 addresses - more than enough.
 183          * (Even 16 instead of 12 should work, but let's be paranoid).
 184          */
 185 };
 186
 187
 188 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 2
 189 static void log_option(const char *pfx, const uint8_t *opt)
 190 {
 191         if (dhcp_verbose >= 2) {
 192                 char buf[256 * 2 + 2];
 193                 *bin2hex(buf, (void*) (opt + OPT_DATA), opt[OPT_LEN]) = '\0';
 194                 bb_info_msg("%s: 0x%02x %s", pfx, opt[OPT_CODE], buf);
 195         }
 196 }
 197 #else
 198 # define log_option(pfx, opt) ((void)0)
 199 #endif
 200
 201 unsigned FAST_FUNC udhcp_option_idx(const char *name, const char *option_strings)
 202 {
 203         int n = index_in_strings(option_strings, name);
 204         if (n >= 0)
 205                 return n;
 206
 207         {
 208                 char *buf, *d;
 209                 const char *s;
 210
 211                 s = option_strings;
 212                 while (*s)
 213                         s += strlen(s) + 1;
 214
 215                 d = buf = xzalloc(s - option_strings);
 216                 s = option_strings;
 217                 while (!(*s == '\0' && s[1] == '\0')) {
 218                         *d++ = (*s == '\0' ? ' ' : *s);
 219                         s++;
 220                 }
 221                 bb_error_msg_and_die("unknown option '%s', known options: %s", name, buf);
 222         }
 223 }
 224
 225 /* Get an option with bounds checking (warning, result is not aligned) */
 226 uint8_t* FAST_FUNC udhcp_get_option(struct dhcp_packet *packet, int code)
 227 {
 228         uint8_t *optionptr;
 229         int len;
 230         int rem;
 231         int overload = 0;
 232         enum {
 233                 FILE_FIELD101  = FILE_FIELD  * 0x101,
 234                 SNAME_FIELD101 = SNAME_FIELD * 0x101,
 235         };
 236
 237         /* option bytes: [code][len][data1][data2]..[dataLEN] */
 238         optionptr = packet->options;
 239         rem = sizeof(packet->options);
 240         while (1) {
 241                 if (rem <= 0) {
 242  complain:
 243                         bb_simple_error_msg("bad packet, malformed option field");
 244                         return NULL;
 245                 }
 246
 247                 /* DHCP_PADDING and DHCP_END have no [len] byte */
 248                 if (optionptr[OPT_CODE] == DHCP_PADDING) {
 249                         rem--;
 250                         optionptr++;
 251                         continue;
 252                 }
 253                 if (optionptr[OPT_CODE] == DHCP_END) {
 254                         if ((overload & FILE_FIELD101) == FILE_FIELD) {
 255                                 /* can use packet->file, and didn't look at it yet */
 256                                 overload |= FILE_FIELD101; /* "we looked at it" */
 257                                 optionptr = packet->file;
 258                                 rem = sizeof(packet->file);
 259                                 continue;
 260                         }
 261                         if ((overload & SNAME_FIELD101) == SNAME_FIELD) {
 262                                 /* can use packet->sname, and didn't look at it yet */
 263                                 overload |= SNAME_FIELD101; /* "we looked at it" */
 264                                 optionptr = packet->sname;
 265                                 rem = sizeof(packet->sname);
 266                                 continue;
 267                         }
 268                         break;
 269                 }
 270
 271                 if (rem <= OPT_LEN)
 272                         goto complain; /* complain and return NULL */
 273                 len = 2 + optionptr[OPT_LEN];
 274                 rem -= len;
 275                 if (rem < 0)
 276                         goto complain; /* complain and return NULL */
 277
 278                 if (optionptr[OPT_CODE] == code) {
 279                         if (optionptr[OPT_LEN] == 0) {
 280                                 /* So far no valid option with length 0 known.
 281                                  * Having this check means that searching
 282                                  * for DHCP_MESSAGE_TYPE need not worry
 283                                  * that returned pointer might be unsafe
 284                                  * to dereference.
 285                                  */
 286                                 goto complain; /* complain and return NULL */
 287                         }
 288                         log_option("option found", optionptr);
 289                         return optionptr + OPT_DATA;
 290                 }
 291
 292                 if (optionptr[OPT_CODE] == DHCP_OPTION_OVERLOAD) {
 293                         if (len >= 3)
 294                                 overload |= optionptr[OPT_DATA];
 295                         /* fall through */
 296                 }
 297                 optionptr += len;
 298         }
 299
 300         /* log3 because udhcpc uses it a lot - very noisy */
 301         log3("option 0x%02x not found", code);
 302         return NULL;
 303 }
 304
 305 uint8_t* FAST_FUNC udhcp_get_option32(struct dhcp_packet *packet, int code)
 306 {
 307         uint8_t *r = udhcp_get_option(packet, code);
 308         if (r) {
 309                 if (r[-OPT_DATA + OPT_LEN] != 4)
 310                         r = NULL;
 311         }
 312         return r;
 313 }
 314
 315 /* Return the position of the 'end' option (no bounds checking) */
 316 int FAST_FUNC udhcp_end_option(uint8_t *optionptr)
 317 {
 318         int i = 0;
 319
 320         while (optionptr[i] != DHCP_END) {
 321                 if (optionptr[i] != DHCP_PADDING)
 322                         i += optionptr[i + OPT_LEN] + OPT_DATA-1;
 323                 i++;
 324         }
 325         return i;
 326 }
 327
 328 /* Add an option (supplied in binary form) to the options.
 329  * Option format: [code][len][data1][data2]..[dataLEN]
 330  */
 331 void FAST_FUNC udhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt)
 332 {
 333         unsigned len;
 334         uint8_t *optionptr = packet->options;
 335         unsigned end = udhcp_end_option(optionptr);
 336
 337         len = OPT_DATA + addopt[OPT_LEN];
 338         /* end position + (option code/length + addopt length) + end option */
 339         if (end + len + 1 >= DHCP_OPTIONS_BUFSIZE) {
 340 //TODO: learn how to use overflow option if we exhaust packet->options[]
 341                 bb_error_msg("option 0x%02x did not fit into the packet",
 342                                 addopt[OPT_CODE]);
 343                 return;
 344         }
 345         log_option("adding option", addopt);
 346         memcpy(optionptr + end, addopt, len);
 347         optionptr[end + len] = DHCP_END;
 348 }
 349
 350 #if ENABLE_UDHCPC || ENABLE_UDHCPD
 351 /* Add an one to four byte option to a packet */
 352 void FAST_FUNC udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, uint32_t data)
 353 {
 354         const struct dhcp_optflag *dh;
 355
 356         for (dh = dhcp_optflags; dh->code; dh++) {
 357                 if (dh->code == code) {
 358                         uint8_t option[6], len;
 359
 360                         option[OPT_CODE] = code;
 361                         len = dhcp_option_lengths[dh->flags & OPTION_TYPE_MASK];
 362                         option[OPT_LEN] = len;
 363                         if (BB_BIG_ENDIAN)
 364                                 data <<= 8 * (4 - len);
 365                         /* Assignment is unaligned! */
 366                         move_to_unaligned32(&option[OPT_DATA], data);
 367                         udhcp_add_binary_option(packet, option);
 368                         return;
 369                 }
 370         }
 371
 372         bb_error_msg("can't add option 0x%02x", code);
 373 }
 374 #endif
 375
 376 /* Find option 'code' in opt_list */
 377 struct option_set* FAST_FUNC udhcp_find_option(struct option_set *opt_list, uint8_t code)
 378 {
 379         while (opt_list && opt_list->data[OPT_CODE] < code)
 380                 opt_list = opt_list->next;
 381
 382         if (opt_list && opt_list->data[OPT_CODE] == code)
 383                 return opt_list;
 384         return NULL;
 385 }
 386
 387 /* Parse string to IP in network order */
 388 int FAST_FUNC udhcp_str2nip(const char *str, void *arg)
 389 {
 390         len_and_sockaddr *lsa;
 391
 392         lsa = host_and_af2sockaddr(str, 0, AF_INET);
 393         if (!lsa)
 394                 return 0;
 395         /* arg maybe unaligned */
 396         move_to_unaligned32((uint32_t*)arg, lsa->u.sin.sin_addr.s_addr);
 397         free(lsa);
 398         return 1;
 399 }
 400
 401 /* udhcp_str2optset:
 402  * Parse string option representation to binary form and add it to opt_list.
 403  * Called to parse "udhcpc -x OPTNAME:OPTVAL"
 404  * and to parse udhcpd.conf's "opt OPTNAME OPTVAL" directives.
 405  */
 406 /* helper: add an option to the opt_list */
 407 #if !ENABLE_UDHCPC6
 408 #define attach_option(opt_list, optflag, buffer, length, dhcpv6) \
 409         attach_option(opt_list, optflag, buffer, length)
 410 #endif
 411 static NOINLINE void attach_option(
 412                 struct option_set **opt_list,
 413                 const struct dhcp_optflag *optflag,
 414                 char *buffer,
 415                 int length,
 416                 bool dhcpv6)
 417 {
 418         IF_NOT_UDHCPC6(bool dhcpv6 = 0;)
 419         struct option_set *existing;
 420         char *allocated = NULL;
 421
 422         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_BIN) {
 423                 const char *end;
 424                 allocated = xstrdup(buffer); /* more than enough */
 425                 end = hex2bin(allocated, buffer, 255);
 426                 if (errno)
 427                         bb_error_msg_and_die("malformed hex string '%s'", buffer);
 428                 length = end - allocated;
 429                 buffer = allocated;
 430         }
 431 #if ENABLE_FEATURE_UDHCP_RFC3397
 432         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_DNS_STRING) {
 433                 /* reuse buffer and length for RFC1035-formatted string */
 434                 allocated = buffer = (char *)dname_enc(/*NULL, 0,*/ buffer, &length);
 435         }
 436 #endif
 437
 438         existing = udhcp_find_option(*opt_list, optflag->code);
 439         if (!existing) {
 440                 struct option_set *new, **curr;
 441
 442                 /* make a new option */
 443                 log2("attaching option %02x to list", optflag->code);
 444                 new = xmalloc(sizeof(*new));
 445                 if (!dhcpv6) {
 446                         new->data = xmalloc(length + OPT_DATA);
 447                         new->data[OPT_CODE] = optflag->code;
 448                         new->data[OPT_LEN] = length;
 449                         memcpy(new->data + OPT_DATA, buffer, length);
 450                 } else {
 451                         new->data = xmalloc(length + D6_OPT_DATA);
 452                         new->data[D6_OPT_CODE] = optflag->code >> 8;
 453                         new->data[D6_OPT_CODE + 1] = optflag->code & 0xff;
 454                         new->data[D6_OPT_LEN] = length >> 8;
 455                         new->data[D6_OPT_LEN + 1] = length & 0xff;
 456                         memcpy(new->data + D6_OPT_DATA, buffer,
 457                                         length);
 458                 }
 459
 460                 curr = opt_list;
 461                 while (*curr && (*curr)->data[OPT_CODE] < optflag->code)
 462                         curr = &(*curr)->next;
 463
 464                 new->next = *curr;
 465                 *curr = new;
 466                 goto ret;
 467         }
 468
 469         if (optflag->flags & OPTION_LIST) {
 470                 unsigned old_len;
 471
 472                 /* add it to an existing option */
 473                 log2("attaching option %02x to existing member of list", optflag->code);
 474                 old_len = existing->data[OPT_LEN];
 475                 if (old_len + length < 255) {
 476                         /* actually 255 is ok too, but adding a space can overlow it */
 477
 478                         existing->data = xrealloc(existing->data, OPT_DATA + 1 + old_len + length);
 479 // So far dhcp_optflags[] has no OPTION_STRING[_HOST] | OPTION_LIST items
 480 #if 0
 481                         if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING
 482                          || (optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING_HOST
 483                         ) {
 484                                 /* add space separator between STRING options in a list */
 485                                 existing->data[OPT_DATA + old_len] = ' ';
 486                                 old_len++;
 487                         }
 488 #endif
 489
 490                         memcpy(existing->data + OPT_DATA + old_len, buffer, length);
 491                         existing->data[OPT_LEN] = old_len + length;
 492                 } /* else, ignore the data, we could put this in a second option in the future */
 493         } /* else, ignore the new data */
 494
 495  ret:
 496         free(allocated);
 497 }
 498
 499 int FAST_FUNC udhcp_str2optset(const char *const_str, void *arg,
 500                 const struct dhcp_optflag *optflags, const char *option_strings,
 501                 bool dhcpv6)
 502 {
 503         struct option_set **opt_list = arg;
 504         char *opt;
 505         char *str;
 506         const struct dhcp_optflag *optflag;
 507         struct dhcp_optflag userdef_optflag;
 508         unsigned optcode;
 509         int retval;
 510         /* IP_PAIR needs 8 bytes, STATIC_ROUTES needs 9 max */
 511         char buffer[9] ALIGNED(4);
 512         uint16_t *result_u16 = (uint16_t *) buffer;
 513         uint32_t *result_u32 = (uint32_t *) buffer;
 514
 515         /* Cheat, the only *const* str possible is "" */
 516         str = (char *) const_str;
 517         opt = strtok(str, " \t=:");
 518         if (!opt)
 519                 return 0;
 520
 521         optcode = bb_strtou(opt, NULL, 0);
 522         if (!errno && optcode < 255) {
 523                 /* Raw (numeric) option code.
 524                  * Initially assume binary (hex-str), but if "str" or 'str'
 525                  * is seen later, switch to STRING.
 526                  */
 527                 userdef_optflag.flags = OPTION_BIN;
 528                 userdef_optflag.code = optcode;
 529                 optflag = &userdef_optflag;
 530         } else {
 531                 optflag = &optflags[udhcp_option_idx(opt, option_strings)];
 532         }
 533
 534         /* Loop to handle OPTION_LIST case, else execute just once */
 535         retval = 0;
 536         do {
 537                 int length;
 538                 char *val;
 539
 540                 if (optflag->flags == OPTION_BIN) {
 541                         val = strtok(NULL, ""); /* do not split "'q w e'" */
 542                         if (val) trim(val);
 543                 } else
 544                         val = strtok(NULL, ", \t");
 545                 if (!val)
 546                         break;
 547
 548                 length = dhcp_option_lengths[optflag->flags & OPTION_TYPE_MASK];
 549                 retval = 0;
 550                 opt = buffer; /* new meaning for variable opt */
 551
 552                 switch (optflag->flags & OPTION_TYPE_MASK) {
 553                 case OPTION_IP:
 554                         retval = udhcp_str2nip(val, buffer);
 555                         break;
 556                 case OPTION_IP_PAIR:
 557                         retval = udhcp_str2nip(val, buffer);
 558                         val = strtok(NULL, ", \t/-");
 559                         if (!val)
 560                                 retval = 0;
 561                         if (retval)
 562                                 retval = udhcp_str2nip(val, buffer + 4);
 563                         break;
 564  case_OPTION_STRING:
 565                 case OPTION_STRING:
 566                 case OPTION_STRING_HOST:
 567 #if ENABLE_FEATURE_UDHCP_RFC3397
 568                 case OPTION_DNS_STRING:
 569 #endif
 570                         length = strnlen(val, 254);
 571                         if (length > 0) {
 572                                 opt = val;
 573                                 retval = 1;
 574                         }
 575                         break;
 576 //              case OPTION_BOOLEAN: {
 577 //                      static const char no_yes[] ALIGN1 = "no\0yes\0";
 578 //                      buffer[0] = retval = index_in_strings(no_yes, val);
 579 //                      retval++; /* 0 - bad; 1: "no" 2: "yes" */
 580 //                      break;
 581 //              }
 582                 case OPTION_U8:
 583                         buffer[0] = bb_strtou32(val, NULL, 0);
 584                         retval = (errno == 0);
 585                         break;
 586                 /* htonX are macros in older libc's, using temp var
 587                  * in code below for safety */
 588                 /* TODO: use bb_strtoX? */
 589                 case OPTION_U16: {
 590                         uint32_t tmp = bb_strtou32(val, NULL, 0);
 591                         *result_u16 = htons(tmp);
 592                         retval = (errno == 0 /*&& tmp < 0x10000*/);
 593                         break;
 594                 }
 595 //              case OPTION_S16: {
 596 //                      long tmp = bb_strtoi32(val, NULL, 0);
 597 //                      *result_u16 = htons(tmp);
 598 //                      retval = (errno == 0);
 599 //                      break;
 600 //              }
 601                 case OPTION_U32: {
 602                         uint32_t tmp = bb_strtou32(val, NULL, 0);
 603                         *result_u32 = htonl(tmp);
 604                         retval = (errno == 0);
 605                         break;
 606                 }
 607                 case OPTION_S32: {
 608                         int32_t tmp = bb_strtoi32(val, NULL, 0);
 609                         *result_u32 = htonl(tmp);
 610                         retval = (errno == 0);
 611                         break;
 612                 }
 613                 case OPTION_STATIC_ROUTES: {
 614                         /* Input: "a.b.c.d/m" */
 615                         /* Output: mask(1 byte),pfx(0-4 bytes),gw(4 bytes) */
 616                         unsigned mask;
 617                         char *slash = strchr(val, '/');
 618                         if (slash) {
 619                                 *slash = '\0';
 620                                 retval = udhcp_str2nip(val, buffer + 1);
 621                                 buffer[0] = mask = bb_strtou(slash + 1, NULL, 10);
 622                                 val = strtok(NULL, ", \t/-");
 623                                 if (!val || mask > 32 || errno)
 624                                         retval = 0;
 625                                 if (retval) {
 626                                         length = ((mask + 7) >> 3) + 5;
 627                                         retval = udhcp_str2nip(val, buffer + (length - 4));
 628                                 }
 629                         }
 630                         break;
 631                 }
 632                 case OPTION_BIN:
 633                         /* Raw (numeric) option code. Is it a string? */
 634                         if (val[0] == '"' || val[0] == '\'') {
 635                                 char delim = val[0];
 636                                 char *end = last_char_is(val + 1, delim);
 637                                 if (end) {
 638                                         *end = '\0';
 639                                         val++;
 640                                         userdef_optflag.flags = OPTION_STRING;
 641                                         goto case_OPTION_STRING;
 642                                 }
 643                         }
 644                         /* No: hex-str option, handled in attach_option() */
 645                         opt = val;
 646                         retval = 1;
 647                         break;
 648                 default:
 649                         break;
 650                 }
 651
 652                 if (retval)
 653                         attach_option(opt_list, optflag, opt, length, dhcpv6);
 654         } while (retval && (optflag->flags & OPTION_LIST));
 655
 656         return retval;
 657 }
 658
 659 /* note: ip is a pointer to an IPv6 in network order, possibly misaliged */
 660 int FAST_FUNC sprint_nip6(char *dest, /*const char *pre,*/ const uint8_t *ip)
 661 {
 662         char hexstrbuf[16 * 2];
 663         bin2hex(hexstrbuf, (void*)ip, 16);
 664         return sprintf(dest, /* "%s" */
 665                 "%.4s:%.4s:%.4s:%.4s:%.4s:%.4s:%.4s:%.4s",
 666                 /* pre, */
 667                 hexstrbuf + 0 * 4,
 668                 hexstrbuf + 1 * 4,
 669                 hexstrbuf + 2 * 4,
 670                 hexstrbuf + 3 * 4,
 671                 hexstrbuf + 4 * 4,
 672                 hexstrbuf + 5 * 4,
 673                 hexstrbuf + 6 * 4,
 674                 hexstrbuf + 7 * 4
 675         );
 676 }