1 /* 2 * dhcpcd - DHCP client daemon 3 * Copyright (c) 2006-2012 Roy Marples <roy (at) marples.name> 4 * All rights reserved 5 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <ctype.h> 29 #include <errno.h> 30 #include <fcntl.h> 31 #include <stdlib.h> 32 #include <string.h> 33 #include <syslog.h> 34 #include <unistd.h> 35 36 #include "config.h" 37 #include "common.h" 38 #include "dhcp.h" 39 40 #define REQUEST (1 << 0) 41 #define UINT8 (1 << 1) 42 #define UINT16 (1 << 2) 43 #define SINT16 (1 << 3) 44 #define UINT32 (1 << 4) 45 #define SINT32 (1 << 5) 46 #define IPV4 (1 << 6) 47 #define STRING (1 << 7) 48 #define PAIR (1 << 8) 49 #define ARRAY (1 << 9) 50 #define RFC3361 (1 << 10) 51 #define RFC3397 (1 << 11) 52 #define RFC3442 (1 << 12) 53 #define RFC5969 (1 << 13) 54 55 #define IPV4R IPV4 | REQUEST 56 57 #define DAD "Duplicate address detected" 58 59 /* Our aggregate option buffer. 60 * We ONLY use this when options are split, which for most purposes is 61 * practically never. See RFC3396 for details. */ 62 static uint8_t *opt_buffer; 63 64 struct dhcp_opt { 65 uint8_t option; 66 int type; 67 const char *var; 68 }; 69 70 static const struct dhcp_opt const dhcp_opts[] = { 71 { 1, IPV4 | REQUEST, "subnet_mask" }, 72 /* RFC 3442 states that the CSR has to come before all other 73 * routes. For completeness, we also specify static routes, 74 * then routers. */ 75 { 121, RFC3442, "classless_static_routes" }, 76 { 249, RFC3442, "ms_classless_static_routes" }, 77 { 33, IPV4 | ARRAY | REQUEST, "static_routes" }, 78 { 3, IPV4 | ARRAY | REQUEST, "routers" }, 79 { 2, UINT32, "time_offset" }, 80 { 4, IPV4 | ARRAY, "time_servers" }, 81 { 5, IPV4 | ARRAY, "ien116_name_servers" }, 82 /* Explicitly include DNS in the list of parameters requested in the DNS request. 83 * Without this some DHCP servers may skip the DNS entries in the DHCP replies.*/ 84 { 6, IPV4 | ARRAY | REQUEST, "domain_name_servers" }, 85 { 7, IPV4 | ARRAY, "log_servers" }, 86 { 8, IPV4 | ARRAY, "cookie_servers" }, 87 { 9, IPV4 | ARRAY, "lpr_servers" }, 88 { 10, IPV4 | ARRAY, "impress_servers" }, 89 { 11, IPV4 | ARRAY, "resource_location_servers" }, 90 { 12, STRING, "host_name" }, 91 { 13, UINT16, "boot_size" }, 92 { 14, STRING, "merit_dump" }, 93 /* Explicitly include DNS in the list of parameters requested in the DNS request. 94 * Without this some DHCP servers may skip the DNS entries in the DHCP replies.*/ 95 { 15, STRING | REQUEST, "domain_name" }, 96 { 16, IPV4, "swap_server" }, 97 { 17, STRING, "root_path" }, 98 { 18, STRING, "extensions_path" }, 99 { 19, UINT8, "ip_forwarding" }, 100 { 20, UINT8, "non_local_source_routing" }, 101 { 21, IPV4 | ARRAY, "policy_filter" }, 102 { 22, SINT16, "max_dgram_reassembly" }, 103 { 23, UINT16, "default_ip_ttl" }, 104 { 24, UINT32, "path_mtu_aging_timeout" }, 105 { 25, UINT16 | ARRAY, "path_mtu_plateau_table" }, 106 { 26, UINT16, "interface_mtu" }, 107 { 27, UINT8, "all_subnets_local" }, 108 { 28, IPV4 | REQUEST, "broadcast_address" }, 109 { 29, UINT8, "perform_mask_discovery" }, 110 { 30, UINT8, "mask_supplier" }, 111 { 31, UINT8, "router_discovery" }, 112 { 32, IPV4, "router_solicitation_address" }, 113 { 34, UINT8, "trailer_encapsulation" }, 114 { 35, UINT32, "arp_cache_timeout" }, 115 { 36, UINT16, "ieee802_3_encapsulation" }, 116 { 37, UINT8, "default_tcp_ttl" }, 117 { 38, UINT32, "tcp_keepalive_interval" }, 118 { 39, UINT8, "tcp_keepalive_garbage" }, 119 { 40, STRING, "nis_domain" }, 120 { 41, IPV4 | ARRAY, "nis_servers" }, 121 { 42, IPV4 | ARRAY, "ntp_servers" }, 122 { 43, STRING, "vendor_encapsulated_options" }, 123 { 44, IPV4 | ARRAY, "netbios_name_servers" }, 124 { 45, IPV4, "netbios_dd_server" }, 125 { 46, UINT8, "netbios_node_type" }, 126 { 47, STRING, "netbios_scope" }, 127 { 48, IPV4 | ARRAY, "font_servers" }, 128 { 49, IPV4 | ARRAY, "x_display_manager" }, 129 { 50, IPV4, "dhcp_requested_address" }, 130 { 51, UINT32 | REQUEST, "dhcp_lease_time" }, 131 { 52, UINT8, "dhcp_option_overload" }, 132 { 53, UINT8, "dhcp_message_type" }, 133 { 54, IPV4, "dhcp_server_identifier" }, 134 { 55, UINT8 | ARRAY, "dhcp_parameter_request_list" }, 135 { 56, STRING, "dhcp_message" }, 136 { 57, UINT16, "dhcp_max_message_size" }, 137 { 58, UINT32 | REQUEST, "dhcp_renewal_time" }, 138 { 59, UINT32 | REQUEST, "dhcp_rebinding_time" }, 139 { 64, STRING, "nisplus_domain" }, 140 { 65, IPV4 | ARRAY, "nisplus_servers" }, 141 { 66, STRING, "tftp_server_name" }, 142 { 67, STRING, "bootfile_name" }, 143 { 68, IPV4 | ARRAY, "mobile_ip_home_agent" }, 144 { 69, IPV4 | ARRAY, "smtp_server" }, 145 { 70, IPV4 | ARRAY, "pop_server" }, 146 { 71, IPV4 | ARRAY, "nntp_server" }, 147 { 72, IPV4 | ARRAY, "www_server" }, 148 { 73, IPV4 | ARRAY, "finger_server" }, 149 { 74, IPV4 | ARRAY, "irc_server" }, 150 { 75, IPV4 | ARRAY, "streettalk_server" }, 151 { 76, IPV4 | ARRAY, "streettalk_directory_assistance_server" }, 152 { 77, STRING, "user_class" }, 153 { 81, STRING | RFC3397, "fqdn_name" }, 154 { 85, IPV4 | ARRAY, "nds_servers" }, 155 { 86, STRING, "nds_tree_name" }, 156 { 87, STRING, "nds_context" }, 157 { 88, STRING | RFC3397, "bcms_controller_names" }, 158 { 89, IPV4 | ARRAY, "bcms_controller_address" }, 159 { 91, UINT32, "client_last_transaction_time" }, 160 { 92, IPV4 | ARRAY, "associated_ip" }, 161 { 98, STRING, "uap_servers" }, 162 { 112, IPV4 | ARRAY, "netinfo_server_address" }, 163 { 113, STRING, "netinfo_server_tag" }, 164 { 114, STRING, "default_url" }, 165 { 118, IPV4, "subnet_selection" }, 166 { 119, STRING | RFC3397, "domain_search" }, 167 { 120, STRING | RFC3361, "sip_server" }, 168 { 212, RFC5969, "sixrd" }, 169 { 0, 0, NULL } 170 }; 171 172 static const char *if_params[] = { 173 "interface", 174 "reason", 175 "pid", 176 "ifmetric", 177 "ifwireless", 178 "ifflags", 179 "profile", 180 "interface_order", 181 NULL 182 }; 183 184 static const char *dhcp_params[] = { 185 "ip_address", 186 "subnet_cidr", 187 "network_number", 188 "ssid", 189 "filename", 190 "server_name", 191 NULL 192 }; 193 194 void 195 print_options(void) 196 { 197 const struct dhcp_opt *opt; 198 const char **p; 199 200 for (p = if_params; *p; p++) 201 printf(" - %s\n", *p); 202 203 for (p = dhcp_params; *p; p++) 204 printf(" %s\n", *p); 205 206 for (opt = dhcp_opts; opt->option; opt++) 207 if (opt->var) 208 printf("%03d %s\n", opt->option, opt->var); 209 } 210 211 int make_option_mask(uint8_t *mask, const char *opts, int add) 212 { 213 char *token, *o, *p, *t; 214 const struct dhcp_opt *opt; 215 int match, n; 216 217 o = p = xstrdup(opts); 218 while ((token = strsep(&p, ", "))) { 219 if (*token == '\0') 220 continue; 221 for (opt = dhcp_opts; opt->option; opt++) { 222 if (!opt->var) 223 continue; 224 match = 0; 225 if (strcmp(opt->var, token) == 0) 226 match = 1; 227 else { 228 errno = 0; 229 n = strtol(token, &t, 0); 230 if (errno == 0 && !*t) 231 if (opt->option == n) 232 match = 1; 233 } 234 if (match) { 235 if (add == 2 && !(opt->type & IPV4)) { 236 free(o); 237 errno = EINVAL; 238 return -1; 239 } 240 if (add == 1 || add == 2) 241 add_option_mask(mask, 242 opt->option); 243 else 244 del_option_mask(mask, 245 opt->option); 246 break; 247 } 248 } 249 if (!opt->option) { 250 free(o); 251 errno = ENOENT; 252 return -1; 253 } 254 } 255 free(o); 256 return 0; 257 } 258 259 static int 260 valid_length(uint8_t option, int dl, int *type) 261 { 262 const struct dhcp_opt *opt; 263 ssize_t sz; 264 265 if (dl == 0) 266 return -1; 267 268 for (opt = dhcp_opts; opt->option; opt++) { 269 if (opt->option != option) 270 continue; 271 272 if (type) 273 *type = opt->type; 274 275 if (opt->type == 0 || 276 opt->type & (STRING | RFC3442 | RFC5969)) 277 return 0; 278 279 sz = 0; 280 if (opt->type & (UINT32 | IPV4)) 281 sz = sizeof(uint32_t); 282 if (opt->type & UINT16) 283 sz = sizeof(uint16_t); 284 if (opt->type & UINT8) 285 sz = sizeof(uint8_t); 286 if (opt->type & (IPV4 | ARRAY)) 287 return dl % sz; 288 return (dl == sz ? 0 : -1); 289 } 290 291 /* unknown option, so let it pass */ 292 return 0; 293 } 294 295 #ifdef DEBUG_MEMORY 296 static void 297 free_option_buffer(void) 298 { 299 free(opt_buffer); 300 } 301 #endif 302 303 #define get_option_raw(dhcp, opt) get_option(dhcp, opt, NULL, NULL) 304 static const uint8_t * 305 get_option(const struct dhcp_message *dhcp, uint8_t opt, int *len, int *type) 306 { 307 const uint8_t *p = dhcp->options; 308 const uint8_t *e = p + sizeof(dhcp->options); 309 uint8_t l, ol = 0; 310 uint8_t o = 0; 311 uint8_t overl = 0; 312 uint8_t *bp = NULL; 313 const uint8_t *op = NULL; 314 int bl = 0; 315 316 while (p < e) { 317 o = *p++; 318 if (o == opt) { 319 if (op) { 320 if (!opt_buffer) { 321 opt_buffer = xmalloc(sizeof(*dhcp)); 322 #ifdef DEBUG_MEMORY 323 atexit(free_option_buffer); 324 #endif 325 } 326 if (!bp) 327 bp = opt_buffer; 328 memcpy(bp, op, ol); 329 bp += ol; 330 } 331 ol = *p; 332 op = p + 1; 333 bl += ol; 334 } 335 switch (o) { 336 case DHO_PAD: 337 continue; 338 case DHO_END: 339 if (overl & 1) { 340 /* bit 1 set means parse boot file */ 341 overl &= ~1; 342 p = dhcp->bootfile; 343 e = p + sizeof(dhcp->bootfile); 344 } else if (overl & 2) { 345 /* bit 2 set means parse server name */ 346 overl &= ~2; 347 p = dhcp->servername; 348 e = p + sizeof(dhcp->servername); 349 } else 350 goto exit; 351 break; 352 case DHO_OPTIONSOVERLOADED: 353 /* Ensure we only get this option once */ 354 if (!overl) 355 overl = p[1]; 356 break; 357 } 358 l = *p++; 359 p += l; 360 } 361 362 exit: 363 if (valid_length(opt, bl, type) == -1) { 364 errno = EINVAL; 365 return NULL; 366 } 367 if (len) 368 *len = bl; 369 if (bp) { 370 memcpy(bp, op, ol); 371 return (const uint8_t *)opt_buffer; 372 } 373 if (op) 374 return op; 375 errno = ENOENT; 376 return NULL; 377 } 378 379 int 380 get_option_addr(struct in_addr *a, const struct dhcp_message *dhcp, 381 uint8_t option) 382 { 383 const uint8_t *p = get_option_raw(dhcp, option); 384 385 if (!p) 386 return -1; 387 memcpy(&a->s_addr, p, sizeof(a->s_addr)); 388 return 0; 389 } 390 391 int 392 get_option_uint32(uint32_t *i, const struct dhcp_message *dhcp, uint8_t option) 393 { 394 const uint8_t *p = get_option_raw(dhcp, option); 395 uint32_t d; 396 397 if (!p) 398 return -1; 399 memcpy(&d, p, sizeof(d)); 400 *i = ntohl(d); 401 return 0; 402 } 403 404 int 405 get_option_uint16(uint16_t *i, const struct dhcp_message *dhcp, uint8_t option) 406 { 407 const uint8_t *p = get_option_raw(dhcp, option); 408 uint16_t d; 409 410 if (!p) 411 return -1; 412 memcpy(&d, p, sizeof(d)); 413 *i = ntohs(d); 414 return 0; 415 } 416 417 int 418 get_option_uint8(uint8_t *i, const struct dhcp_message *dhcp, uint8_t option) 419 { 420 const uint8_t *p = get_option_raw(dhcp, option); 421 422 if (!p) 423 return -1; 424 if (i) 425 *i = *(p); 426 return 0; 427 } 428 429 /* Decode an RFC3397 DNS search order option into a space 430 * separated string. Returns length of string (including 431 * terminating zero) or zero on error. out may be NULL 432 * to just determine output length. */ 433 ssize_t 434 decode_rfc3397(char *out, ssize_t len, int pl, const uint8_t *p) 435 { 436 const uint8_t *r, *q = p; 437 int count = 0, l, hops; 438 uint8_t ltype; 439 440 while (q - p < pl) { 441 r = NULL; 442 hops = 0; 443 /* We check we are inside our length again incase 444 * the data is NOT terminated correctly. */ 445 while ((l = *q++) && q - p < pl) { 446 ltype = l & 0xc0; 447 if (ltype == 0x80 || ltype == 0x40) 448 return 0; 449 else if (ltype == 0xc0) { /* pointer */ 450 l = (l & 0x3f) << 8; 451 l |= *q++; 452 /* save source of first jump. */ 453 if (!r) 454 r = q; 455 hops++; 456 if (hops > 255) 457 return 0; 458 q = p + l; 459 if (q - p >= pl) 460 return 0; 461 } else { 462 /* straightforward name segment, add with '.' */ 463 count += l + 1; 464 if (out) { 465 if ((ssize_t)l + 1 > len) { 466 errno = ENOBUFS; 467 return -1; 468 } 469 memcpy(out, q, l); 470 out += l; 471 *out++ = '.'; 472 len -= l; 473 len--; 474 } 475 q += l; 476 } 477 } 478 /* change last dot to space */ 479 if (out) 480 *(out - 1) = ' '; 481 if (r) 482 q = r; 483 } 484 485 /* change last space to zero terminator */ 486 if (out) 487 *(out - 1) = 0; 488 489 return count; 490 } 491 492 static ssize_t 493 decode_rfc3442(char *out, ssize_t len, int pl, const uint8_t *p) 494 { 495 const uint8_t *e; 496 ssize_t b, bytes = 0, ocets; 497 uint8_t cidr; 498 struct in_addr addr; 499 char *o = out; 500 501 /* Minimum is 5 -first is CIDR and a router length of 4 */ 502 if (pl < 5) { 503 errno = EINVAL; 504 return -1; 505 } 506 507 e = p + pl; 508 while (p < e) { 509 cidr = *p++; 510 if (cidr > 32) { 511 errno = EINVAL; 512 return -1; 513 } 514 ocets = (cidr + 7) / 8; 515 if (!out) { 516 p += 4 + ocets; 517 bytes += ((4 * 4) * 2) + 4; 518 continue; 519 } 520 if ((((4 * 4) * 2) + 4) > len) { 521 errno = ENOBUFS; 522 return -1; 523 } 524 if (o != out) { 525 *o++ = ' '; 526 len--; 527 } 528 /* If we have ocets then we have a destination and netmask */ 529 if (ocets > 0) { 530 addr.s_addr = 0; 531 memcpy(&addr.s_addr, p, ocets); 532 b = snprintf(o, len, "%s/%d", inet_ntoa(addr), cidr); 533 p += ocets; 534 } else 535 b = snprintf(o, len, "0.0.0.0/0"); 536 o += b; 537 len -= b; 538 539 /* Finally, snag the router */ 540 memcpy(&addr.s_addr, p, 4); 541 p += 4; 542 b = snprintf(o, len, " %s", inet_ntoa(addr)); 543 o += b; 544 len -= b; 545 } 546 547 if (out) 548 return o - out; 549 return bytes; 550 } 551 552 static struct rt * 553 decode_rfc3442_rt(int dl, const uint8_t *data) 554 { 555 const uint8_t *p = data; 556 const uint8_t *e; 557 uint8_t cidr; 558 size_t ocets; 559 struct rt *routes = NULL; 560 struct rt *rt = NULL; 561 562 /* Minimum is 5 -first is CIDR and a router length of 4 */ 563 if (dl < 5) 564 return NULL; 565 566 e = p + dl; 567 while (p < e) { 568 cidr = *p++; 569 if (cidr > 32) { 570 free_routes(routes); 571 errno = EINVAL; 572 return NULL; 573 } 574 575 if (rt) { 576 rt->next = xzalloc(sizeof(*rt)); 577 rt = rt->next; 578 } else { 579 routes = rt = xzalloc(sizeof(*routes)); 580 } 581 rt->next = NULL; 582 583 ocets = (cidr + 7) / 8; 584 /* If we have ocets then we have a destination and netmask */ 585 if (ocets > 0) { 586 memcpy(&rt->dest.s_addr, p, ocets); 587 p += ocets; 588 rt->net.s_addr = htonl(~0U << (32 - cidr)); 589 } 590 591 /* Finally, snag the router */ 592 memcpy(&rt->gate.s_addr, p, 4); 593 p += 4; 594 } 595 return routes; 596 } 597 598 static char * 599 decode_rfc3361(int dl, const uint8_t *data) 600 { 601 uint8_t enc; 602 unsigned int l; 603 char *sip = NULL; 604 struct in_addr addr; 605 char *p; 606 607 if (dl < 2) { 608 errno = EINVAL; 609 return 0; 610 } 611 612 enc = *data++; 613 dl--; 614 switch (enc) { 615 case 0: 616 if ((l = decode_rfc3397(NULL, 0, dl, data)) > 0) { 617 sip = xmalloc(l); 618 decode_rfc3397(sip, l, dl, data); 619 } 620 break; 621 case 1: 622 if (dl == 0 || dl % 4 != 0) { 623 errno = EINVAL; 624 break; 625 } 626 addr.s_addr = INADDR_BROADCAST; 627 l = ((dl / sizeof(addr.s_addr)) * ((4 * 4) + 1)) + 1; 628 sip = p = xmalloc(l); 629 while (dl != 0) { 630 memcpy(&addr.s_addr, data, sizeof(addr.s_addr)); 631 data += sizeof(addr.s_addr); 632 p += snprintf(p, l - (p - sip), "%s ", inet_ntoa(addr)); 633 dl -= sizeof(addr.s_addr); 634 } 635 *--p = '\0'; 636 break; 637 default: 638 errno = EINVAL; 639 return 0; 640 } 641 642 return sip; 643 } 644 645 /* Decode an RFC5969 6rd order option into a space 646 * separated string. Returns length of string (including 647 * terminating zero) or zero on error. */ 648 static ssize_t 649 decode_rfc5969(char *out, ssize_t len, int pl, const uint8_t *p) 650 { 651 uint8_t ipv4masklen, ipv6prefixlen; 652 uint8_t ipv6prefix[16]; 653 uint8_t br[4]; 654 int i; 655 ssize_t b, bytes = 0; 656 657 if (pl < 22) { 658 errno = EINVAL; 659 return 0; 660 } 661 662 ipv4masklen = *p++; 663 pl--; 664 ipv6prefixlen = *p++; 665 pl--; 666 667 for (i = 0; i < 16; i++) { 668 ipv6prefix[i] = *p++; 669 pl--; 670 } 671 if (out) { 672 b= snprintf(out, len, 673 "%d %d " 674 "%02x%02x:%02x%02x:" 675 "%02x%02x:%02x%02x:" 676 "%02x%02x:%02x%02x:" 677 "%02x%02x:%02x%02x", 678 ipv4masklen, ipv6prefixlen, 679 ipv6prefix[0], ipv6prefix[1], ipv6prefix[2], ipv6prefix[3], 680 ipv6prefix[4], ipv6prefix[5], ipv6prefix[6], ipv6prefix[7], 681 ipv6prefix[8], ipv6prefix[9], ipv6prefix[10],ipv6prefix[11], 682 ipv6prefix[12],ipv6prefix[13],ipv6prefix[14], ipv6prefix[15] 683 ); 684 685 len -= b; 686 out += b; 687 bytes += b; 688 } else { 689 bytes += 16 * 2 + 8 + 2 + 1 + 2; 690 } 691 692 while (pl >= 4) { 693 br[0] = *p++; 694 br[1] = *p++; 695 br[2] = *p++; 696 br[3] = *p++; 697 pl -= 4; 698 699 if (out) { 700 b= snprintf(out, len, " %d.%d.%d.%d", 701 br[0], br[1], br[2], br[3]); 702 len -= b; 703 out += b; 704 bytes += b; 705 } else { 706 bytes += (4 * 4); 707 } 708 } 709 710 return bytes; 711 } 712 713 char * 714 get_option_string(const struct dhcp_message *dhcp, uint8_t option) 715 { 716 int type = 0; 717 int len; 718 const uint8_t *p; 719 char *s; 720 721 p = get_option(dhcp, option, &len, &type); 722 if (!p || *p == '\0') 723 return NULL; 724 725 if (type & RFC3397) { 726 type = decode_rfc3397(NULL, 0, len, p); 727 if (!type) { 728 errno = EINVAL; 729 return NULL; 730 } 731 s = xmalloc(sizeof(char) * type); 732 decode_rfc3397(s, type, len, p); 733 return s; 734 } 735 736 if (type & RFC3361) 737 return decode_rfc3361(len, p); 738 739 s = xmalloc(sizeof(char) * (len + 1)); 740 memcpy(s, p, len); 741 s[len] = '\0'; 742 return s; 743 } 744 745 /* This calculates the netmask that we should use for static routes. 746 * This IS different from the calculation used to calculate the netmask 747 * for an interface address. */ 748 static uint32_t 749 route_netmask(uint32_t ip_in) 750 { 751 /* used to be unsigned long - check if error */ 752 uint32_t p = ntohl(ip_in); 753 uint32_t t; 754 755 if (IN_CLASSA(p)) 756 t = ~IN_CLASSA_NET; 757 else { 758 if (IN_CLASSB(p)) 759 t = ~IN_CLASSB_NET; 760 else { 761 if (IN_CLASSC(p)) 762 t = ~IN_CLASSC_NET; 763 else 764 t = 0; 765 } 766 } 767 768 while (t & p) 769 t >>= 1; 770 771 return (htonl(~t)); 772 } 773 774 /* We need to obey routing options. 775 * If we have a CSR then we only use that. 776 * Otherwise we add static routes and then routers. */ 777 struct rt * 778 get_option_routes(const struct dhcp_message *dhcp, 779 const char *ifname, unsigned long long *opts) 780 { 781 const uint8_t *p; 782 const uint8_t *e; 783 struct rt *routes = NULL; 784 struct rt *route = NULL; 785 int len; 786 787 /* If we have CSR's then we MUST use these only */ 788 p = get_option(dhcp, DHO_CSR, &len, NULL); 789 /* Check for crappy MS option */ 790 if (!p) 791 p = get_option(dhcp, DHO_MSCSR, &len, NULL); 792 if (p) { 793 routes = decode_rfc3442_rt(len, p); 794 if (routes) { 795 if (!(*opts & DHCPCD_CSR_WARNED)) { 796 syslog(LOG_DEBUG, 797 "%s: using Classless Static Routes", 798 ifname); 799 *opts |= DHCPCD_CSR_WARNED; 800 } 801 return routes; 802 } 803 } 804 805 /* OK, get our static routes first. */ 806 p = get_option(dhcp, DHO_STATICROUTE, &len, NULL); 807 if (p) { 808 e = p + len; 809 while (p < e) { 810 if (route) { 811 route->next = xmalloc(sizeof(*route)); 812 route = route->next; 813 } else 814 routes = route = xmalloc(sizeof(*routes)); 815 route->next = NULL; 816 memcpy(&route->dest.s_addr, p, 4); 817 p += 4; 818 memcpy(&route->gate.s_addr, p, 4); 819 p += 4; 820 route->net.s_addr = route_netmask(route->dest.s_addr); 821 } 822 } 823 824 /* Now grab our routers */ 825 p = get_option(dhcp, DHO_ROUTER, &len, NULL); 826 if (p) { 827 e = p + len; 828 while (p < e) { 829 if (route) { 830 route->next = xzalloc(sizeof(*route)); 831 route = route->next; 832 } else 833 routes = route = xzalloc(sizeof(*route)); 834 memcpy(&route->gate.s_addr, p, 4); 835 p += 4; 836 } 837 } 838 839 return routes; 840 } 841 842 static size_t 843 encode_rfc1035(const char *src, uint8_t *dst) 844 { 845 uint8_t *p = dst; 846 uint8_t *lp = p++; 847 848 if (*src == '\0') 849 return 0; 850 for (; *src; src++) { 851 if (*src == '\0') 852 break; 853 if (*src == '.') { 854 /* Skip the trailing . */ 855 if (src[1] == '\0') 856 break; 857 *lp = p - lp - 1; 858 if (*lp == '\0') 859 return p - dst; 860 lp = p++; 861 } else 862 *p++ = (uint8_t)*src; 863 } 864 *lp = p - lp - 1; 865 *p++ = '\0'; 866 return p - dst; 867 } 868 869 #define PUTADDR(_type, _val) \ 870 { \ 871 *p++ = _type; \ 872 *p++ = 4; \ 873 memcpy(p, &_val.s_addr, 4); \ 874 p += 4; \ 875 } 876 877 int 878 dhcp_message_add_addr(struct dhcp_message *dhcp, 879 uint8_t type, struct in_addr addr) 880 { 881 uint8_t *p; 882 size_t len; 883 884 p = dhcp->options; 885 while (*p != DHO_END) { 886 p++; 887 p += *p + 1; 888 } 889 890 len = p - (uint8_t *)dhcp; 891 if (len + 6 > sizeof(*dhcp)) { 892 errno = ENOMEM; 893 return -1; 894 } 895 896 PUTADDR(type, addr); 897 *p = DHO_END; 898 return 0; 899 } 900 901 ssize_t 902 make_message(struct dhcp_message **message, 903 const struct interface *iface, 904 uint8_t type) 905 { 906 struct dhcp_message *dhcp; 907 uint8_t *m, *lp, *p; 908 uint8_t *n_params = NULL; 909 time_t up = uptime() - iface->start_uptime; 910 uint32_t ul; 911 uint16_t sz; 912 size_t len; 913 const char *hp; 914 const struct dhcp_opt *opt; 915 const struct if_options *ifo = iface->state->options; 916 const struct dhcp_lease *lease = &iface->state->lease; 917 918 dhcp = xzalloc(sizeof (*dhcp)); 919 m = (uint8_t *)dhcp; 920 p = dhcp->options; 921 922 if ((type == DHCP_INFORM || type == DHCP_RELEASE || 923 (type == DHCP_REQUEST && 924 iface->net.s_addr == lease->net.s_addr && 925 (iface->state->new == NULL || 926 iface->state->new->cookie == htonl(MAGIC_COOKIE))))) 927 { 928 dhcp->ciaddr = iface->addr.s_addr; 929 /* In-case we haven't actually configured the address yet */ 930 if (type == DHCP_INFORM && iface->addr.s_addr == 0) 931 dhcp->ciaddr = lease->addr.s_addr; 932 } 933 934 dhcp->op = DHCP_BOOTREQUEST; 935 dhcp->hwtype = iface->family; 936 switch (iface->family) { 937 case ARPHRD_ETHER: 938 case ARPHRD_IEEE802: 939 dhcp->hwlen = iface->hwlen; 940 memcpy(&dhcp->chaddr, &iface->hwaddr, iface->hwlen); 941 break; 942 } 943 944 if (ifo->options & DHCPCD_BROADCAST && 945 dhcp->ciaddr == 0 && 946 type != DHCP_DECLINE && 947 type != DHCP_RELEASE) 948 dhcp->flags = htons(BROADCAST_FLAG); 949 950 if (type != DHCP_DECLINE && type != DHCP_RELEASE) { 951 if (up < 0 || up > (time_t)UINT16_MAX) 952 dhcp->secs = htons((uint16_t)UINT16_MAX); 953 else 954 dhcp->secs = htons(up); 955 } 956 dhcp->xid = iface->state->xid; 957 dhcp->cookie = htonl(MAGIC_COOKIE); 958 959 *p++ = DHO_MESSAGETYPE; 960 *p++ = 1; 961 *p++ = type; 962 963 if (iface->clientid) { 964 *p++ = DHO_CLIENTID; 965 memcpy(p, iface->clientid, iface->clientid[0] + 1); 966 p += iface->clientid[0] + 1; 967 } 968 969 if (lease->addr.s_addr && lease->cookie == htonl(MAGIC_COOKIE)) { 970 if (type == DHCP_DECLINE || 971 (type == DHCP_REQUEST && 972 lease->addr.s_addr != iface->addr.s_addr)) 973 { 974 PUTADDR(DHO_IPADDRESS, lease->addr); 975 if (lease->server.s_addr) 976 PUTADDR(DHO_SERVERID, lease->server); 977 } 978 979 if (type == DHCP_RELEASE) { 980 if (lease->server.s_addr) 981 PUTADDR(DHO_SERVERID, lease->server); 982 } 983 } 984 985 if (type == DHCP_DECLINE) { 986 *p++ = DHO_MESSAGE; 987 len = strlen(DAD); 988 *p++ = len; 989 memcpy(p, DAD, len); 990 p += len; 991 } 992 993 if (type == DHCP_DISCOVER && ifo->options & DHCPCD_REQUEST) 994 PUTADDR(DHO_IPADDRESS, ifo->req_addr); 995 996 if (type == DHCP_DISCOVER || 997 type == DHCP_INFORM || 998 type == DHCP_REQUEST) 999 { 1000 *p++ = DHO_MAXMESSAGESIZE; 1001 *p++ = 2; 1002 sz = get_mtu(iface->name); 1003 if (sz < MTU_MIN) { 1004 if (set_mtu(iface->name, MTU_MIN) == 0) 1005 sz = MTU_MIN; 1006 } else if (sz > MTU_MAX) { 1007 /* Even though our MTU could be greater than 1008 * MTU_MAX (1500) dhcpcd does not presently 1009 * handle DHCP packets any bigger. */ 1010 sz = MTU_MAX; 1011 } 1012 sz = htons(sz); 1013 memcpy(p, &sz, 2); 1014 p += 2; 1015 1016 if (ifo->userclass[0]) { 1017 *p++ = DHO_USERCLASS; 1018 memcpy(p, ifo->userclass, ifo->userclass[0] + 1); 1019 p += ifo->userclass[0] + 1; 1020 } 1021 1022 if (ifo->vendorclassid[0]) { 1023 *p++ = DHO_VENDORCLASSID; 1024 memcpy(p, ifo->vendorclassid, 1025 ifo->vendorclassid[0] + 1); 1026 p += ifo->vendorclassid[0] + 1; 1027 } 1028 1029 1030 if (type != DHCP_INFORM) { 1031 if (ifo->leasetime != 0) { 1032 *p++ = DHO_LEASETIME; 1033 *p++ = 4; 1034 ul = htonl(ifo->leasetime); 1035 memcpy(p, &ul, 4); 1036 p += 4; 1037 } 1038 } 1039 1040 /* Regardless of RFC2132, we should always send a hostname 1041 * upto the first dot (the short hostname) as otherwise 1042 * confuses some DHCP servers when updating DNS. 1043 * The FQDN option should be used if a FQDN is required. */ 1044 if (ifo->options & DHCPCD_HOSTNAME && ifo->hostname[0]) { 1045 *p++ = DHO_HOSTNAME; 1046 hp = strchr(ifo->hostname, '.'); 1047 if (hp) 1048 len = hp - ifo->hostname; 1049 else 1050 len = strlen(ifo->hostname); 1051 *p++ = len; 1052 memcpy(p, ifo->hostname, len); 1053 p += len; 1054 } 1055 if (ifo->fqdn != FQDN_DISABLE && ifo->hostname[0]) { 1056 /* IETF DHC-FQDN option (81), RFC4702 */ 1057 *p++ = DHO_FQDN; 1058 lp = p; 1059 *p++ = 3; 1060 /* 1061 * Flags: 0000NEOS 1062 * S: 1 => Client requests Server to update 1063 * a RR in DNS as well as PTR 1064 * O: 1 => Server indicates to client that 1065 * DNS has been updated 1066 * E: 1 => Name data is DNS format 1067 * N: 1 => Client requests Server to not 1068 * update DNS 1069 */ 1070 *p++ = (ifo->fqdn & 0x09) | 0x04; 1071 *p++ = 0; /* from server for PTR RR */ 1072 *p++ = 0; /* from server for A RR if S=1 */ 1073 ul = encode_rfc1035(ifo->hostname, p); 1074 *lp += ul; 1075 p += ul; 1076 } 1077 1078 /* vendor is already encoded correctly, so just add it */ 1079 if (ifo->vendor[0]) { 1080 *p++ = DHO_VENDOR; 1081 memcpy(p, ifo->vendor, ifo->vendor[0] + 1); 1082 p += ifo->vendor[0] + 1; 1083 } 1084 1085 *p++ = DHO_PARAMETERREQUESTLIST; 1086 n_params = p; 1087 *p++ = 0; 1088 for (opt = dhcp_opts; opt->option; opt++) { 1089 if (!(opt->type & REQUEST || 1090 has_option_mask(ifo->requestmask, opt->option))) 1091 continue; 1092 if (type == DHCP_INFORM && 1093 (opt->option == DHO_RENEWALTIME || 1094 opt->option == DHO_REBINDTIME)) 1095 continue; 1096 *p++ = opt->option; 1097 } 1098 *n_params = p - n_params - 1; 1099 } 1100 *p++ = DHO_END; 1101 1102 #ifdef BOOTP_MESSAGE_LENTH_MIN 1103 /* Some crappy DHCP servers think they have to obey the BOOTP minimum 1104 * message length. 1105 * They are wrong, but we should still cater for them. */ 1106 while (p - m < BOOTP_MESSAGE_LENTH_MIN) 1107 *p++ = DHO_PAD; 1108 #endif 1109 1110 *message = dhcp; 1111 return p - m; 1112 } 1113 1114 ssize_t 1115 write_lease(const struct interface *iface, const struct dhcp_message *dhcp) 1116 { 1117 int fd; 1118 ssize_t bytes = sizeof(*dhcp); 1119 const uint8_t *p = dhcp->options; 1120 const uint8_t *e = p + sizeof(dhcp->options); 1121 uint8_t l; 1122 uint8_t o = 0; 1123 1124 /* We don't write BOOTP leases */ 1125 if (is_bootp(dhcp)) { 1126 unlink(iface->leasefile); 1127 return 0; 1128 } 1129 1130 syslog(LOG_DEBUG, "%s: writing lease `%s'", 1131 iface->name, iface->leasefile); 1132 1133 fd = open(iface->leasefile, O_WRONLY | O_CREAT | O_TRUNC, 0444); 1134 #ifdef ANDROID 1135 if (fd == -1 && errno == EACCES) { 1136 /* the lease file might have been created when dhcpcd was running as root */ 1137 unlink(iface->leasefile); 1138 fd = open(iface->leasefile, O_WRONLY | O_CREAT | O_TRUNC, 0444); 1139 } 1140 #endif 1141 if (fd == -1) { 1142 syslog(LOG_ERR, "%s: open: %m", iface->name); 1143 return -1; 1144 } 1145 1146 /* Only write as much as we need */ 1147 while (p < e) { 1148 o = *p; 1149 if (o == DHO_END) { 1150 bytes = p - (const uint8_t *)dhcp; 1151 break; 1152 } 1153 p++; 1154 if (o != DHO_PAD) { 1155 l = *p++; 1156 p += l; 1157 } 1158 } 1159 bytes = write(fd, dhcp, bytes); 1160 close(fd); 1161 return bytes; 1162 } 1163 1164 struct dhcp_message * 1165 read_lease(const struct interface *iface) 1166 { 1167 int fd; 1168 struct dhcp_message *dhcp; 1169 ssize_t bytes; 1170 1171 fd = open(iface->leasefile, O_RDONLY); 1172 if (fd == -1) { 1173 if (errno != ENOENT) 1174 syslog(LOG_ERR, "%s: open `%s': %m", 1175 iface->name, iface->leasefile); 1176 return NULL; 1177 } 1178 syslog(LOG_DEBUG, "%s: reading lease `%s'", 1179 iface->name, iface->leasefile); 1180 dhcp = xmalloc(sizeof(*dhcp)); 1181 memset(dhcp, 0, sizeof(*dhcp)); 1182 bytes = read(fd, dhcp, sizeof(*dhcp)); 1183 close(fd); 1184 if (bytes < 0) { 1185 free(dhcp); 1186 dhcp = NULL; 1187 } 1188 return dhcp; 1189 } 1190 1191 static ssize_t 1192 print_string(char *s, ssize_t len, int dl, const uint8_t *data) 1193 { 1194 uint8_t c; 1195 const uint8_t *e, *p; 1196 ssize_t bytes = 0; 1197 ssize_t r; 1198 1199 e = data + dl; 1200 while (data < e) { 1201 c = *data++; 1202 if (c == '\0') { 1203 /* If rest is all NULL, skip it. */ 1204 for (p = data; p < e; p++) 1205 if (*p != '\0') 1206 break; 1207 if (p == e) 1208 break; 1209 } 1210 if (!isascii(c) || !isprint(c)) { 1211 if (s) { 1212 if (len < 5) { 1213 errno = ENOBUFS; 1214 return -1; 1215 } 1216 r = snprintf(s, len, "\\%03o", c); 1217 len -= r; 1218 bytes += r; 1219 s += r; 1220 } else 1221 bytes += 4; 1222 continue; 1223 } 1224 switch (c) { 1225 case '"': /* FALLTHROUGH */ 1226 case '\'': /* FALLTHROUGH */ 1227 case '$': /* FALLTHROUGH */ 1228 case '`': /* FALLTHROUGH */ 1229 case '\\': /* FALLTHROUGH */ 1230 case '|': /* FALLTHROUGH */ 1231 case '&': 1232 if (s) { 1233 if (len < 3) { 1234 errno = ENOBUFS; 1235 return -1; 1236 } 1237 *s++ = '\\'; 1238 len--; 1239 } 1240 bytes++; 1241 break; 1242 } 1243 if (s) { 1244 *s++ = c; 1245 len--; 1246 } 1247 bytes++; 1248 } 1249 1250 /* NULL */ 1251 if (s) 1252 *s = '\0'; 1253 bytes++; 1254 return bytes; 1255 } 1256 1257 static ssize_t 1258 print_option(char *s, ssize_t len, int type, int dl, const uint8_t *data) 1259 { 1260 const uint8_t *e, *t; 1261 uint16_t u16; 1262 int16_t s16; 1263 uint32_t u32; 1264 int32_t s32; 1265 struct in_addr addr; 1266 ssize_t bytes = 0; 1267 ssize_t l; 1268 char *tmp; 1269 1270 if (type & RFC3397) { 1271 l = decode_rfc3397(NULL, 0, dl, data); 1272 if (l < 1) 1273 return l; 1274 tmp = xmalloc(l); 1275 decode_rfc3397(tmp, l, dl, data); 1276 l = print_string(s, len, l - 1, (uint8_t *)tmp); 1277 free(tmp); 1278 return l; 1279 } 1280 1281 if (type & RFC3361) { 1282 if ((tmp = decode_rfc3361(dl, data)) == NULL) 1283 return -1; 1284 l = strlen(tmp); 1285 l = print_string(s, len, l - 1, (uint8_t *)tmp); 1286 free(tmp); 1287 return l; 1288 } 1289 1290 if (type & RFC3442) 1291 return decode_rfc3442(s, len, dl, data); 1292 1293 if (type & RFC5969) 1294 return decode_rfc5969(s, len, dl, data); 1295 1296 if (type & STRING) { 1297 /* Some DHCP servers return NULL strings */ 1298 if (*data == '\0') 1299 return 0; 1300 return print_string(s, len, dl, data); 1301 } 1302 1303 if (!s) { 1304 if (type & UINT8) 1305 l = 3; 1306 else if (type & UINT16) { 1307 l = 5; 1308 dl /= 2; 1309 } else if (type & SINT16) { 1310 l = 6; 1311 dl /= 2; 1312 } else if (type & UINT32) { 1313 l = 10; 1314 dl /= 4; 1315 } else if (type & SINT32) { 1316 l = 11; 1317 dl /= 4; 1318 } else if (type & IPV4) { 1319 l = 16; 1320 dl /= 4; 1321 } else { 1322 errno = EINVAL; 1323 return -1; 1324 } 1325 return (l + 1) * dl; 1326 } 1327 1328 t = data; 1329 e = data + dl; 1330 while (data < e) { 1331 if (data != t) { 1332 *s++ = ' '; 1333 bytes++; 1334 len--; 1335 } 1336 if (type & UINT8) { 1337 l = snprintf(s, len, "%d", *data); 1338 data++; 1339 } else if (type & UINT16) { 1340 memcpy(&u16, data, sizeof(u16)); 1341 u16 = ntohs(u16); 1342 l = snprintf(s, len, "%d", u16); 1343 data += sizeof(u16); 1344 } else if (type & SINT16) { 1345 memcpy(&s16, data, sizeof(s16)); 1346 s16 = ntohs(s16); 1347 l = snprintf(s, len, "%d", s16); 1348 data += sizeof(s16); 1349 } else if (type & UINT32) { 1350 memcpy(&u32, data, sizeof(u32)); 1351 u32 = ntohl(u32); 1352 l = snprintf(s, len, "%d", u32); 1353 data += sizeof(u32); 1354 } else if (type & SINT32) { 1355 memcpy(&s32, data, sizeof(s32)); 1356 s32 = ntohl(s32); 1357 l = snprintf(s, len, "%d", s32); 1358 data += sizeof(s32); 1359 } else if (type & IPV4) { 1360 memcpy(&addr.s_addr, data, sizeof(addr.s_addr)); 1361 l = snprintf(s, len, "%s", inet_ntoa(addr)); 1362 data += sizeof(addr.s_addr); 1363 } else 1364 l = 0; 1365 len -= l; 1366 bytes += l; 1367 s += l; 1368 } 1369 1370 return bytes; 1371 } 1372 1373 ssize_t 1374 configure_env(char **env, const char *prefix, const struct dhcp_message *dhcp, 1375 const struct if_options *ifo) 1376 { 1377 unsigned int i; 1378 const uint8_t *p; 1379 int pl; 1380 struct in_addr addr; 1381 struct in_addr net; 1382 struct in_addr brd; 1383 char *val, *v; 1384 const struct dhcp_opt *opt; 1385 ssize_t len, e = 0; 1386 char **ep; 1387 char cidr[4]; 1388 uint8_t overl = 0; 1389 1390 get_option_uint8(&overl, dhcp, DHO_OPTIONSOVERLOADED); 1391 1392 if (!env) { 1393 for (opt = dhcp_opts; opt->option; opt++) { 1394 if (!opt->var) 1395 continue; 1396 if (has_option_mask(ifo->nomask, opt->option)) 1397 continue; 1398 if (get_option_raw(dhcp, opt->option)) 1399 e++; 1400 } 1401 if (dhcp->yiaddr || dhcp->ciaddr) 1402 e += 5; 1403 if (*dhcp->bootfile && !(overl & 1)) 1404 e++; 1405 if (*dhcp->servername && !(overl & 2)) 1406 e++; 1407 return e; 1408 } 1409 1410 ep = env; 1411 if (dhcp->yiaddr || dhcp->ciaddr) { 1412 /* Set some useful variables that we derive from the DHCP 1413 * message but are not necessarily in the options */ 1414 addr.s_addr = dhcp->yiaddr ? dhcp->yiaddr : dhcp->ciaddr; 1415 setvar(&ep, prefix, "ip_address", inet_ntoa(addr)); 1416 if (get_option_addr(&net, dhcp, DHO_SUBNETMASK) == -1) { 1417 net.s_addr = get_netmask(addr.s_addr); 1418 setvar(&ep, prefix, "subnet_mask", inet_ntoa(net)); 1419 } 1420 i = inet_ntocidr(net); 1421 snprintf(cidr, sizeof(cidr), "%d", inet_ntocidr(net)); 1422 setvar(&ep, prefix, "subnet_cidr", cidr); 1423 if (get_option_addr(&brd, dhcp, DHO_BROADCAST) == -1) { 1424 brd.s_addr = addr.s_addr | ~net.s_addr; 1425 setvar(&ep, prefix, "broadcast_address", inet_ntoa(brd)); 1426 } 1427 addr.s_addr = dhcp->yiaddr & net.s_addr; 1428 setvar(&ep, prefix, "network_number", inet_ntoa(addr)); 1429 } 1430 1431 if (*dhcp->bootfile && !(overl & 1)) 1432 setvar(&ep, prefix, "filename", (const char *)dhcp->bootfile); 1433 if (*dhcp->servername && !(overl & 2)) 1434 setvar(&ep, prefix, "server_name", (const char *)dhcp->servername); 1435 1436 for (opt = dhcp_opts; opt->option; opt++) { 1437 if (!opt->var) 1438 continue; 1439 if (has_option_mask(ifo->nomask, opt->option)) 1440 continue; 1441 val = NULL; 1442 p = get_option(dhcp, opt->option, &pl, NULL); 1443 if (!p) 1444 continue; 1445 /* We only want the FQDN name */ 1446 if (opt->option == DHO_FQDN) { 1447 p += 3; 1448 pl -= 3; 1449 } 1450 len = print_option(NULL, 0, opt->type, pl, p); 1451 if (len < 0) 1452 return -1; 1453 e = strlen(prefix) + strlen(opt->var) + len + 4; 1454 v = val = *ep++ = xmalloc(e); 1455 v += snprintf(val, e, "%s_%s=", prefix, opt->var); 1456 if (len != 0) 1457 print_option(v, len, opt->type, pl, p); 1458 } 1459 1460 return ep - env; 1461 } 1462 1463 void 1464 get_lease(struct dhcp_lease *lease, const struct dhcp_message *dhcp) 1465 { 1466 struct timeval now; 1467 1468 lease->cookie = dhcp->cookie; 1469 /* BOOTP does not set yiaddr for replies when ciaddr is set. */ 1470 if (dhcp->yiaddr) 1471 lease->addr.s_addr = dhcp->yiaddr; 1472 else 1473 lease->addr.s_addr = dhcp->ciaddr; 1474 if (get_option_addr(&lease->net, dhcp, DHO_SUBNETMASK) == -1) 1475 lease->net.s_addr = get_netmask(lease->addr.s_addr); 1476 if (get_option_addr(&lease->brd, dhcp, DHO_BROADCAST) == -1) 1477 lease->brd.s_addr = lease->addr.s_addr | ~lease->net.s_addr; 1478 if (get_option_uint32(&lease->leasetime, dhcp, DHO_LEASETIME) == 0) { 1479 /* Ensure that we can use the lease */ 1480 get_monotonic(&now); 1481 if (now.tv_sec + (time_t)lease->leasetime < now.tv_sec) 1482 lease->leasetime = ~0U; /* Infinite lease */ 1483 } else 1484 lease->leasetime = ~0U; /* Default to infinite lease */ 1485 if (get_option_uint32(&lease->renewaltime, dhcp, DHO_RENEWALTIME) != 0) 1486 lease->renewaltime = 0; 1487 if (get_option_uint32(&lease->rebindtime, dhcp, DHO_REBINDTIME) != 0) 1488 lease->rebindtime = 0; 1489 if (get_option_addr(&lease->server, dhcp, DHO_SERVERID) != 0) 1490 lease->server.s_addr = INADDR_ANY; 1491 } 1492