src/libsystemd-network/sd-dhcp-lease.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   Copyright (C) 2013 Intel Corporation. All rights reserved.
   4   Copyright (C) 2014 Tom Gundersen
   5 ***/
   6
   7 #include <arpa/inet.h>
   8 #include <errno.h>
   9 #include <stdio.h>
  10 #include <stdio_ext.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13
  14 #include "sd-dhcp-lease.h"
  15
  16 #include "alloc-util.h"
  17 #include "dhcp-lease-internal.h"
  18 #include "dhcp-protocol.h"
  19 #include "dns-domain.h"
  20 #include "fd-util.h"
  21 #include "fileio.h"
  22 #include "hexdecoct.h"
  23 #include "hostname-util.h"
  24 #include "in-addr-util.h"
  25 #include "network-internal.h"
  26 #include "parse-util.h"
  27 #include "stdio-util.h"
  28 #include "string-util.h"
  29 #include "unaligned.h"
  30
  31 int sd_dhcp_lease_get_address(sd_dhcp_lease *lease, struct in_addr *addr) {
  32         assert_return(lease, -EINVAL);
  33         assert_return(addr, -EINVAL);
  34
  35         if (lease->address == 0)
  36                 return -ENODATA;
  37
  38         addr->s_addr = lease->address;
  39         return 0;
  40 }
  41
  42 int sd_dhcp_lease_get_broadcast(sd_dhcp_lease *lease, struct in_addr *addr) {
  43         assert_return(lease, -EINVAL);
  44         assert_return(addr, -EINVAL);
  45
  46         if (!lease->have_broadcast)
  47                 return -ENODATA;
  48
  49         addr->s_addr = lease->broadcast;
  50         return 0;
  51 }
  52
  53 int sd_dhcp_lease_get_lifetime(sd_dhcp_lease *lease, uint32_t *lifetime) {
  54         assert_return(lease, -EINVAL);
  55         assert_return(lifetime, -EINVAL);
  56
  57         if (lease->lifetime <= 0)
  58                 return -ENODATA;
  59
  60         *lifetime = lease->lifetime;
  61         return 0;
  62 }
  63
  64 int sd_dhcp_lease_get_t1(sd_dhcp_lease *lease, uint32_t *t1) {
  65         assert_return(lease, -EINVAL);
  66         assert_return(t1, -EINVAL);
  67
  68         if (lease->t1 <= 0)
  69                 return -ENODATA;
  70
  71         *t1 = lease->t1;
  72         return 0;
  73 }
  74
  75 int sd_dhcp_lease_get_t2(sd_dhcp_lease *lease, uint32_t *t2) {
  76         assert_return(lease, -EINVAL);
  77         assert_return(t2, -EINVAL);
  78
  79         if (lease->t2 <= 0)
  80                 return -ENODATA;
  81
  82         *t2 = lease->t2;
  83         return 0;
  84 }
  85
  86 int sd_dhcp_lease_get_mtu(sd_dhcp_lease *lease, uint16_t *mtu) {
  87         assert_return(lease, -EINVAL);
  88         assert_return(mtu, -EINVAL);
  89
  90         if (lease->mtu <= 0)
  91                 return -ENODATA;
  92
  93         *mtu = lease->mtu;
  94         return 0;
  95 }
  96
  97 int sd_dhcp_lease_get_dns(sd_dhcp_lease *lease, const struct in_addr **addr) {
  98         assert_return(lease, -EINVAL);
  99         assert_return(addr, -EINVAL);
 100
 101         if (lease->dns_size <= 0)
 102                 return -ENODATA;
 103
 104         *addr = lease->dns;
 105         return (int) lease->dns_size;
 106 }
 107
 108 int sd_dhcp_lease_get_ntp(sd_dhcp_lease *lease, const struct in_addr **addr) {
 109         assert_return(lease, -EINVAL);
 110         assert_return(addr, -EINVAL);
 111
 112         if (lease->ntp_size <= 0)
 113                 return -ENODATA;
 114
 115         *addr = lease->ntp;
 116         return (int) lease->ntp_size;
 117 }
 118
 119 int sd_dhcp_lease_get_domainname(sd_dhcp_lease *lease, const char **domainname) {
 120         assert_return(lease, -EINVAL);
 121         assert_return(domainname, -EINVAL);
 122
 123         if (!lease->domainname)
 124                 return -ENODATA;
 125
 126         *domainname = lease->domainname;
 127         return 0;
 128 }
 129
 130 int sd_dhcp_lease_get_hostname(sd_dhcp_lease *lease, const char **hostname) {
 131         assert_return(lease, -EINVAL);
 132         assert_return(hostname, -EINVAL);
 133
 134         if (!lease->hostname)
 135                 return -ENODATA;
 136
 137         *hostname = lease->hostname;
 138         return 0;
 139 }
 140
 141 int sd_dhcp_lease_get_root_path(sd_dhcp_lease *lease, const char **root_path) {
 142         assert_return(lease, -EINVAL);
 143         assert_return(root_path, -EINVAL);
 144
 145         if (!lease->root_path)
 146                 return -ENODATA;
 147
 148         *root_path = lease->root_path;
 149         return 0;
 150 }
 151
 152 int sd_dhcp_lease_get_router(sd_dhcp_lease *lease, struct in_addr *addr) {
 153         assert_return(lease, -EINVAL);
 154         assert_return(addr, -EINVAL);
 155
 156         if (lease->router == 0)
 157                 return -ENODATA;
 158
 159         addr->s_addr = lease->router;
 160         return 0;
 161 }
 162
 163 int sd_dhcp_lease_get_netmask(sd_dhcp_lease *lease, struct in_addr *addr) {
 164         assert_return(lease, -EINVAL);
 165         assert_return(addr, -EINVAL);
 166
 167         if (!lease->have_subnet_mask)
 168                 return -ENODATA;
 169
 170         addr->s_addr = lease->subnet_mask;
 171         return 0;
 172 }
 173
 174 int sd_dhcp_lease_get_server_identifier(sd_dhcp_lease *lease, struct in_addr *addr) {
 175         assert_return(lease, -EINVAL);
 176         assert_return(addr, -EINVAL);
 177
 178         if (lease->server_address == 0)
 179                 return -ENODATA;
 180
 181         addr->s_addr = lease->server_address;
 182         return 0;
 183 }
 184
 185 int sd_dhcp_lease_get_next_server(sd_dhcp_lease *lease, struct in_addr *addr) {
 186         assert_return(lease, -EINVAL);
 187         assert_return(addr, -EINVAL);
 188
 189         if (lease->next_server == 0)
 190                 return -ENODATA;
 191
 192         addr->s_addr = lease->next_server;
 193         return 0;
 194 }
 195
 196 /*
 197  * The returned routes array must be freed by the caller.
 198  * Route objects have the same lifetime of the lease and must not be freed.
 199  */
 200 int sd_dhcp_lease_get_routes(sd_dhcp_lease *lease, sd_dhcp_route ***routes) {
 201         sd_dhcp_route **ret;
 202         unsigned i;
 203
 204         assert_return(lease, -EINVAL);
 205         assert_return(routes, -EINVAL);
 206
 207         if (lease->static_route_size <= 0)
 208                 return -ENODATA;
 209
 210         ret = new(sd_dhcp_route *, lease->static_route_size);
 211         if (!ret)
 212                 return -ENOMEM;
 213
 214         for (i = 0; i < lease->static_route_size; i++)
 215                 ret[i] = &lease->static_route[i];
 216
 217         *routes = ret;
 218         return (int) lease->static_route_size;
 219 }
 220
 221 int sd_dhcp_lease_get_search_domains(sd_dhcp_lease *lease, char ***domains) {
 222         size_t r;
 223
 224         assert_return(lease, -EINVAL);
 225         assert_return(domains, -EINVAL);
 226
 227         r = strv_length(lease->search_domains);
 228         if (r > 0) {
 229                 *domains = lease->search_domains;
 230                 return (int) r;
 231         }
 232
 233         return -ENODATA;
 234 }
 235
 236 int sd_dhcp_lease_get_vendor_specific(sd_dhcp_lease *lease, const void **data, size_t *data_len) {
 237         assert_return(lease, -EINVAL);
 238         assert_return(data, -EINVAL);
 239         assert_return(data_len, -EINVAL);
 240
 241         if (lease->vendor_specific_len <= 0)
 242                 return -ENODATA;
 243
 244         *data = lease->vendor_specific;
 245         *data_len = lease->vendor_specific_len;
 246         return 0;
 247 }
 248
 249 sd_dhcp_lease *sd_dhcp_lease_ref(sd_dhcp_lease *lease) {
 250
 251         if (!lease)
 252                 return NULL;
 253
 254         assert(lease->n_ref >= 1);
 255         lease->n_ref++;
 256
 257         return lease;
 258 }
 259
 260 sd_dhcp_lease *sd_dhcp_lease_unref(sd_dhcp_lease *lease) {
 261
 262         if (!lease)
 263                 return NULL;
 264
 265         assert(lease->n_ref >= 1);
 266         lease->n_ref--;
 267
 268         if (lease->n_ref > 0)
 269                 return NULL;
 270
 271         while (lease->private_options) {
 272                 struct sd_dhcp_raw_option *option = lease->private_options;
 273
 274                 LIST_REMOVE(options, lease->private_options, option);
 275
 276                 free(option->data);
 277                 free(option);
 278         }
 279
 280         free(lease->hostname);
 281         free(lease->domainname);
 282         free(lease->dns);
 283         free(lease->ntp);
 284         free(lease->static_route);
 285         free(lease->client_id);
 286         free(lease->vendor_specific);
 287         strv_free(lease->search_domains);
 288         return mfree(lease);
 289 }
 290
 291 static int lease_parse_u32(const uint8_t *option, size_t len, uint32_t *ret, uint32_t min) {
 292         assert(option);
 293         assert(ret);
 294
 295         if (len != 4)
 296                 return -EINVAL;
 297
 298         *ret = unaligned_read_be32((be32_t*) option);
 299         if (*ret < min)
 300                 *ret = min;
 301
 302         return 0;
 303 }
 304
 305 static int lease_parse_u16(const uint8_t *option, size_t len, uint16_t *ret, uint16_t min) {
 306         assert(option);
 307         assert(ret);
 308
 309         if (len != 2)
 310                 return -EINVAL;
 311
 312         *ret = unaligned_read_be16((be16_t*) option);
 313         if (*ret < min)
 314                 *ret = min;
 315
 316         return 0;
 317 }
 318
 319 static int lease_parse_be32(const uint8_t *option, size_t len, be32_t *ret) {
 320         assert(option);
 321         assert(ret);
 322
 323         if (len != 4)
 324                 return -EINVAL;
 325
 326         memcpy(ret, option, 4);
 327         return 0;
 328 }
 329
 330 static int lease_parse_string(const uint8_t *option, size_t len, char **ret) {
 331         assert(option);
 332         assert(ret);
 333
 334         if (len <= 0)
 335                 *ret = mfree(*ret);
 336         else {
 337                 char *string;
 338
 339                 /*
 340                  * One trailing NUL byte is OK, we don't mind. See:
 341                  * https://github.com/systemd/systemd/issues/1337
 342                  */
 343                 if (memchr(option, 0, len - 1))
 344                         return -EINVAL;
 345
 346                 string = strndup((const char *) option, len);
 347                 if (!string)
 348                         return -ENOMEM;
 349
 350                 free(*ret);
 351                 *ret = string;
 352         }
 353
 354         return 0;
 355 }
 356
 357 static int lease_parse_domain(const uint8_t *option, size_t len, char **ret) {
 358         _cleanup_free_ char *name = NULL, *normalized = NULL;
 359         int r;
 360
 361         assert(option);
 362         assert(ret);
 363
 364         r = lease_parse_string(option, len, &name);
 365         if (r < 0)
 366                 return r;
 367         if (!name) {
 368                 *ret = mfree(*ret);
 369                 return 0;
 370         }
 371
 372         r = dns_name_normalize(name, &normalized);
 373         if (r < 0)
 374                 return r;
 375
 376         if (is_localhost(normalized))
 377                 return -EINVAL;
 378
 379         if (dns_name_is_root(normalized))
 380                 return -EINVAL;
 381
 382         free_and_replace(*ret, normalized);
 383
 384         return 0;
 385 }
 386
 387 static void filter_bogus_addresses(struct in_addr *addresses, size_t *n) {
 388         size_t i, j;
 389
 390         /* Silently filter DNS/NTP servers supplied to us that do not make outside of the local scope. */
 391
 392         for (i = 0, j = 0; i < *n; i ++) {
 393
 394                 if (in4_addr_is_null(addresses+i) ||
 395                     in4_addr_is_localhost(addresses+i))
 396                         continue;
 397
 398                 addresses[j++] = addresses[i];
 399         }
 400
 401         *n = j;
 402 }
 403
 404 static int lease_parse_in_addrs(const uint8_t *option, size_t len, struct in_addr **ret, size_t *n_ret) {
 405         assert(option);
 406         assert(ret);
 407         assert(n_ret);
 408
 409         if (len <= 0) {
 410                 *ret = mfree(*ret);
 411                 *n_ret = 0;
 412         } else {
 413                 size_t n_addresses;
 414                 struct in_addr *addresses;
 415
 416                 if (len % 4 != 0)
 417                         return -EINVAL;
 418
 419                 n_addresses = len / 4;
 420
 421                 addresses = newdup(struct in_addr, option, n_addresses);
 422                 if (!addresses)
 423                         return -ENOMEM;
 424
 425                 filter_bogus_addresses(addresses, &n_addresses);
 426
 427                 free(*ret);
 428                 *ret = addresses;
 429                 *n_ret = n_addresses;
 430         }
 431
 432         return 0;
 433 }
 434
 435 static int lease_parse_routes(
 436                 const uint8_t *option, size_t len,
 437                 struct sd_dhcp_route **routes, size_t *routes_size, size_t *routes_allocated) {
 438
 439         struct in_addr addr;
 440
 441         assert(option || len <= 0);
 442         assert(routes);
 443         assert(routes_size);
 444         assert(routes_allocated);
 445
 446         if (len <= 0)
 447                 return 0;
 448
 449         if (len % 8 != 0)
 450                 return -EINVAL;
 451
 452         if (!GREEDY_REALLOC(*routes, *routes_allocated, *routes_size + (len / 8)))
 453                 return -ENOMEM;
 454
 455         while (len >= 8) {
 456                 struct sd_dhcp_route *route = *routes + *routes_size;
 457                 int r;
 458
 459                 route->option = SD_DHCP_OPTION_STATIC_ROUTE;
 460                 r = in4_addr_default_prefixlen((struct in_addr*) option, &route->dst_prefixlen);
 461                 if (r < 0) {
 462                         log_debug("Failed to determine destination prefix length from class based IP, ignoring");
 463                         continue;
 464                 }
 465
 466                 assert_se(lease_parse_be32(option, 4, &addr.s_addr) >= 0);
 467                 route->dst_addr = inet_makeaddr(inet_netof(addr), 0);
 468                 option += 4;
 469
 470                 assert_se(lease_parse_be32(option, 4, &route->gw_addr.s_addr) >= 0);
 471                 option += 4;
 472
 473                 len -= 8;
 474                 (*routes_size)++;
 475         }
 476
 477         return 0;
 478 }
 479
 480 /* parses RFC3442 Classless Static Route Option */
 481 static int lease_parse_classless_routes(
 482                 const uint8_t *option, size_t len,
 483                 struct sd_dhcp_route **routes, size_t *routes_size, size_t *routes_allocated) {
 484
 485         assert(option || len <= 0);
 486         assert(routes);
 487         assert(routes_size);
 488         assert(routes_allocated);
 489
 490         if (len <= 0)
 491                 return 0;
 492
 493         /* option format: (subnet-mask-width significant-subnet-octets gateway-ip)*  */
 494
 495         while (len > 0) {
 496                 uint8_t dst_octets;
 497                 struct sd_dhcp_route *route;
 498
 499                 if (!GREEDY_REALLOC(*routes, *routes_allocated, *routes_size + 1))
 500                         return -ENOMEM;
 501
 502                 route = *routes + *routes_size;
 503                 route->option = SD_DHCP_OPTION_CLASSLESS_STATIC_ROUTE;
 504
 505                 dst_octets = (*option == 0 ? 0 : ((*option - 1) / 8) + 1);
 506                 route->dst_prefixlen = *option;
 507                 option++;
 508                 len--;
 509
 510                 /* can't have more than 4 octets in IPv4 */
 511                 if (dst_octets > 4 || len < dst_octets)
 512                         return -EINVAL;
 513
 514                 route->dst_addr.s_addr = 0;
 515                 memcpy(&route->dst_addr.s_addr, option, dst_octets);
 516                 option += dst_octets;
 517                 len -= dst_octets;
 518
 519                 if (len < 4)
 520                         return -EINVAL;
 521
 522                 assert_se(lease_parse_be32(option, 4, &route->gw_addr.s_addr) >= 0);
 523                 option += 4;
 524                 len -= 4;
 525
 526                 (*routes_size)++;
 527         }
 528
 529         return 0;
 530 }
 531
 532 int dhcp_lease_parse_options(uint8_t code, uint8_t len, const void *option, void *userdata) {
 533         sd_dhcp_lease *lease = userdata;
 534         int r;
 535
 536         assert(lease);
 537
 538         switch(code) {
 539
 540         case SD_DHCP_OPTION_IP_ADDRESS_LEASE_TIME:
 541                 r = lease_parse_u32(option, len, &lease->lifetime, 1);
 542                 if (r < 0)
 543                         log_debug_errno(r, "Failed to parse lease time, ignoring: %m");
 544
 545                 break;
 546
 547         case SD_DHCP_OPTION_SERVER_IDENTIFIER:
 548                 r = lease_parse_be32(option, len, &lease->server_address);
 549                 if (r < 0)
 550                         log_debug_errno(r, "Failed to parse server identifier, ignoring: %m");
 551
 552                 break;
 553
 554         case SD_DHCP_OPTION_SUBNET_MASK:
 555                 r = lease_parse_be32(option, len, &lease->subnet_mask);
 556                 if (r < 0)
 557                         log_debug_errno(r, "Failed to parse subnet mask, ignoring: %m");
 558                 else
 559                         lease->have_subnet_mask = true;
 560                 break;
 561
 562         case SD_DHCP_OPTION_BROADCAST:
 563                 r = lease_parse_be32(option, len, &lease->broadcast);
 564                 if (r < 0)
 565                         log_debug_errno(r, "Failed to parse broadcast address, ignoring: %m");
 566                 else
 567                         lease->have_broadcast = true;
 568                 break;
 569
 570         case SD_DHCP_OPTION_ROUTER:
 571                 if (len >= 4) {
 572                         r = lease_parse_be32(option, 4, &lease->router);
 573                         if (r < 0)
 574                                 log_debug_errno(r, "Failed to parse router address, ignoring: %m");
 575                 }
 576                 break;
 577
 578         case SD_DHCP_OPTION_DOMAIN_NAME_SERVER:
 579                 r = lease_parse_in_addrs(option, len, &lease->dns, &lease->dns_size);
 580                 if (r < 0)
 581                         log_debug_errno(r, "Failed to parse DNS server, ignoring: %m");
 582                 break;
 583
 584         case SD_DHCP_OPTION_NTP_SERVER:
 585                 r = lease_parse_in_addrs(option, len, &lease->ntp, &lease->ntp_size);
 586                 if (r < 0)
 587                         log_debug_errno(r, "Failed to parse NTP server, ignoring: %m");
 588                 break;
 589
 590         case SD_DHCP_OPTION_STATIC_ROUTE:
 591                 r = lease_parse_routes(option, len, &lease->static_route, &lease->static_route_size, &lease->static_route_allocated);
 592                 if (r < 0)
 593                         log_debug_errno(r, "Failed to parse static routes, ignoring: %m");
 594                 break;
 595
 596         case SD_DHCP_OPTION_INTERFACE_MTU:
 597                 r = lease_parse_u16(option, len, &lease->mtu, 68);
 598                 if (r < 0)
 599                         log_debug_errno(r, "Failed to parse MTU, ignoring: %m");
 600                 if (lease->mtu < DHCP_DEFAULT_MIN_SIZE) {
 601                         log_debug("MTU value of %" PRIu16 " too small. Using default MTU value of %d instead.", lease->mtu, DHCP_DEFAULT_MIN_SIZE);
 602                         lease->mtu = DHCP_DEFAULT_MIN_SIZE;
 603                 }
 604
 605                 break;
 606
 607         case SD_DHCP_OPTION_DOMAIN_NAME:
 608                 r = lease_parse_domain(option, len, &lease->domainname);
 609                 if (r < 0) {
 610                         log_debug_errno(r, "Failed to parse domain name, ignoring: %m");
 611                         return 0;
 612                 }
 613
 614                 break;
 615
 616         case SD_DHCP_OPTION_DOMAIN_SEARCH_LIST:
 617                 r = dhcp_lease_parse_search_domains(option, len, &lease->search_domains);
 618                 if (r < 0)
 619                         log_debug_errno(r, "Failed to parse Domain Search List, ignoring: %m");
 620                 break;
 621
 622         case SD_DHCP_OPTION_HOST_NAME:
 623                 r = lease_parse_domain(option, len, &lease->hostname);
 624                 if (r < 0) {
 625                         log_debug_errno(r, "Failed to parse host name, ignoring: %m");
 626                         return 0;
 627                 }
 628
 629                 break;
 630
 631         case SD_DHCP_OPTION_ROOT_PATH:
 632                 r = lease_parse_string(option, len, &lease->root_path);
 633                 if (r < 0)
 634                         log_debug_errno(r, "Failed to parse root path, ignoring: %m");
 635                 break;
 636
 637         case SD_DHCP_OPTION_RENEWAL_T1_TIME:
 638                 r = lease_parse_u32(option, len, &lease->t1, 1);
 639                 if (r < 0)
 640                         log_debug_errno(r, "Failed to parse T1 time, ignoring: %m");
 641                 break;
 642
 643         case SD_DHCP_OPTION_REBINDING_T2_TIME:
 644                 r = lease_parse_u32(option, len, &lease->t2, 1);
 645                 if (r < 0)
 646                         log_debug_errno(r, "Failed to parse T2 time, ignoring: %m");
 647                 break;
 648
 649         case SD_DHCP_OPTION_CLASSLESS_STATIC_ROUTE:
 650                 r = lease_parse_classless_routes(
 651                                 option, len,
 652                                 &lease->static_route,
 653                                 &lease->static_route_size,
 654                                 &lease->static_route_allocated);
 655                 if (r < 0)
 656                         log_debug_errno(r, "Failed to parse classless routes, ignoring: %m");
 657                 break;
 658
 659         case SD_DHCP_OPTION_NEW_TZDB_TIMEZONE: {
 660                 _cleanup_free_ char *tz = NULL;
 661
 662                 r = lease_parse_string(option, len, &tz);
 663                 if (r < 0) {
 664                         log_debug_errno(r, "Failed to parse timezone option, ignoring: %m");
 665                         return 0;
 666                 }
 667
 668                 if (!timezone_is_valid(tz, LOG_DEBUG)) {
 669                         log_debug_errno(r, "Timezone is not valid, ignoring: %m");
 670                         return 0;
 671                 }
 672
 673                 free_and_replace(lease->timezone, tz);
 674
 675                 break;
 676         }
 677
 678         case SD_DHCP_OPTION_VENDOR_SPECIFIC:
 679
 680                 if (len <= 0)
 681                         lease->vendor_specific = mfree(lease->vendor_specific);
 682                 else {
 683                         void *p;
 684
 685                         p = memdup(option, len);
 686                         if (!p)
 687                                 return -ENOMEM;
 688
 689                         free(lease->vendor_specific);
 690                         lease->vendor_specific = p;
 691                 }
 692
 693                 lease->vendor_specific_len = len;
 694                 break;
 695
 696         case SD_DHCP_OPTION_PRIVATE_BASE ... SD_DHCP_OPTION_PRIVATE_LAST:
 697                 r = dhcp_lease_insert_private_option(lease, code, option, len);
 698                 if (r < 0)
 699                         return r;
 700
 701                 break;
 702
 703         default:
 704                 log_debug("Ignoring option DHCP option %"PRIu8" while parsing.", code);
 705                 break;
 706         }
 707
 708         return 0;
 709 }
 710
 711 /* Parses compressed domain names. */
 712 int dhcp_lease_parse_search_domains(const uint8_t *option, size_t len, char ***domains) {
 713         _cleanup_strv_free_ char **names = NULL;
 714         size_t pos = 0, cnt = 0;
 715         int r;
 716
 717         assert(domains);
 718         assert_return(option && len > 0, -ENODATA);
 719
 720         while (pos < len) {
 721                 _cleanup_free_ char *name = NULL;
 722                 size_t n = 0, allocated = 0;
 723                 size_t jump_barrier = pos, next_chunk = 0;
 724                 bool first = true;
 725
 726                 for (;;) {
 727                         uint8_t c;
 728                         c = option[pos++];
 729
 730                         if (c == 0) {
 731                                 /* End of name */
 732                                 break;
 733                         } else if (c <= 63) {
 734                                 const char *label;
 735
 736                                 /* Literal label */
 737                                 label = (const char*) (option + pos);
 738                                 pos += c;
 739                                 if (pos >= len)
 740                                         return -EBADMSG;
 741
 742                                 if (!GREEDY_REALLOC(name, allocated, n + !first + DNS_LABEL_ESCAPED_MAX))
 743                                         return -ENOMEM;
 744
 745                                 if (first)
 746                                         first = false;
 747                                 else
 748                                         name[n++] = '.';
 749
 750                                 r = dns_label_escape(label, c, name + n, DNS_LABEL_ESCAPED_MAX);
 751                                 if (r < 0)
 752                                         return r;
 753
 754                                 n += r;
 755                         } else if ((c & 0xc0) == 0xc0) {
 756                                 /* Pointer */
 757
 758                                 uint8_t d;
 759                                 uint16_t ptr;
 760
 761                                 if (pos >= len)
 762                                         return -EBADMSG;
 763
 764                                 d = option[pos++];
 765                                 ptr = (uint16_t) (c & ~0xc0) << 8 | (uint16_t) d;
 766
 767                                 /* Jumps are limited to a "prior occurrence" (RFC-1035 4.1.4) */
 768                                 if (ptr >= jump_barrier)
 769                                         return -EBADMSG;
 770                                 jump_barrier = ptr;
 771
 772                                 /* Save current location so we don't end up re-parsing what's parsed so far. */
 773                                 if (next_chunk == 0)
 774                                         next_chunk = pos;
 775
 776                                 pos = ptr;
 777                         } else
 778                                 return -EBADMSG;
 779                 }
 780
 781                 if (!GREEDY_REALLOC(name, allocated, n + 1))
 782                         return -ENOMEM;
 783                 name[n] = 0;
 784
 785                 r = strv_extend(&names, name);
 786                 if (r < 0)
 787                         return r;
 788
 789                 cnt++;
 790
 791                 if (next_chunk != 0)
 792                       pos = next_chunk;
 793         }
 794
 795         *domains = TAKE_PTR(names);
 796
 797         return cnt;
 798 }
 799
 800 int dhcp_lease_insert_private_option(sd_dhcp_lease *lease, uint8_t tag, const void *data, uint8_t len) {
 801         struct sd_dhcp_raw_option *cur, *option;
 802
 803         assert(lease);
 804
 805         LIST_FOREACH(options, cur, lease->private_options) {
 806                 if (tag < cur->tag)
 807                         break;
 808                 if (tag == cur->tag) {
 809                         log_debug("Ignoring duplicate option, tagged %i.", tag);
 810                         return 0;
 811                 }
 812         }
 813
 814         option = new(struct sd_dhcp_raw_option, 1);
 815         if (!option)
 816                 return -ENOMEM;
 817
 818         option->tag = tag;
 819         option->length = len;
 820         option->data = memdup(data, len);
 821         if (!option->data) {
 822                 free(option);
 823                 return -ENOMEM;
 824         }
 825
 826         LIST_INSERT_BEFORE(options, lease->private_options, cur, option);
 827         return 0;
 828 }
 829
 830 int dhcp_lease_new(sd_dhcp_lease **ret) {
 831         sd_dhcp_lease *lease;
 832
 833         lease = new0(sd_dhcp_lease, 1);
 834         if (!lease)
 835                 return -ENOMEM;
 836
 837         lease->router = INADDR_ANY;
 838         lease->n_ref = 1;
 839
 840         *ret = lease;
 841         return 0;
 842 }
 843
 844 int dhcp_lease_save(sd_dhcp_lease *lease, const char *lease_file) {
 845         _cleanup_free_ char *temp_path = NULL;
 846         _cleanup_fclose_ FILE *f = NULL;
 847         struct sd_dhcp_raw_option *option;
 848         struct in_addr address;
 849         const struct in_addr *addresses;
 850         const void *client_id, *data;
 851         size_t client_id_len, data_len;
 852         const char *string;
 853         uint16_t mtu;
 854         _cleanup_free_ sd_dhcp_route **routes = NULL;
 855         char **search_domains = NULL;
 856         uint32_t t1, t2, lifetime;
 857         int r;
 858
 859         assert(lease);
 860         assert(lease_file);
 861
 862         r = fopen_temporary(lease_file, &f, &temp_path);
 863         if (r < 0)
 864                 goto fail;
 865
 866         (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
 867         (void) fchmod(fileno(f), 0644);
 868
 869         fprintf(f,
 870                 "# This is private data. Do not parse.\n");
 871
 872         r = sd_dhcp_lease_get_address(lease, &address);
 873         if (r >= 0)
 874                 fprintf(f, "ADDRESS=%s\n", inet_ntoa(address));
 875
 876         r = sd_dhcp_lease_get_netmask(lease, &address);
 877         if (r >= 0)
 878                 fprintf(f, "NETMASK=%s\n", inet_ntoa(address));
 879
 880         r = sd_dhcp_lease_get_router(lease, &address);
 881         if (r >= 0)
 882                 fprintf(f, "ROUTER=%s\n", inet_ntoa(address));
 883
 884         r = sd_dhcp_lease_get_server_identifier(lease, &address);
 885         if (r >= 0)
 886                 fprintf(f, "SERVER_ADDRESS=%s\n", inet_ntoa(address));
 887
 888         r = sd_dhcp_lease_get_next_server(lease, &address);
 889         if (r >= 0)
 890                 fprintf(f, "NEXT_SERVER=%s\n", inet_ntoa(address));
 891
 892         r = sd_dhcp_lease_get_broadcast(lease, &address);
 893         if (r >= 0)
 894                 fprintf(f, "BROADCAST=%s\n", inet_ntoa(address));
 895
 896         r = sd_dhcp_lease_get_mtu(lease, &mtu);
 897         if (r >= 0)
 898                 fprintf(f, "MTU=%" PRIu16 "\n", mtu);
 899
 900         r = sd_dhcp_lease_get_t1(lease, &t1);
 901         if (r >= 0)
 902                 fprintf(f, "T1=%" PRIu32 "\n", t1);
 903
 904         r = sd_dhcp_lease_get_t2(lease, &t2);
 905         if (r >= 0)
 906                 fprintf(f, "T2=%" PRIu32 "\n", t2);
 907
 908         r = sd_dhcp_lease_get_lifetime(lease, &lifetime);
 909         if (r >= 0)
 910                 fprintf(f, "LIFETIME=%" PRIu32 "\n", lifetime);
 911
 912         r = sd_dhcp_lease_get_dns(lease, &addresses);
 913         if (r > 0) {
 914                 fputs("DNS=", f);
 915                 serialize_in_addrs(f, addresses, r);
 916                 fputs("\n", f);
 917         }
 918
 919         r = sd_dhcp_lease_get_ntp(lease, &addresses);
 920         if (r > 0) {
 921                 fputs("NTP=", f);
 922                 serialize_in_addrs(f, addresses, r);
 923                 fputs("\n", f);
 924         }
 925
 926         r = sd_dhcp_lease_get_domainname(lease, &string);
 927         if (r >= 0)
 928                 fprintf(f, "DOMAINNAME=%s\n", string);
 929
 930         r = sd_dhcp_lease_get_search_domains(lease, &search_domains);
 931         if (r > 0) {
 932                 fputs("DOMAIN_SEARCH_LIST=", f);
 933                 fputstrv(f, search_domains, NULL, NULL);
 934                 fputs("\n", f);
 935         }
 936
 937         r = sd_dhcp_lease_get_hostname(lease, &string);
 938         if (r >= 0)
 939                 fprintf(f, "HOSTNAME=%s\n", string);
 940
 941         r = sd_dhcp_lease_get_root_path(lease, &string);
 942         if (r >= 0)
 943                 fprintf(f, "ROOT_PATH=%s\n", string);
 944
 945         r = sd_dhcp_lease_get_routes(lease, &routes);
 946         if (r > 0)
 947                 serialize_dhcp_routes(f, "ROUTES", routes, r);
 948
 949         r = sd_dhcp_lease_get_timezone(lease, &string);
 950         if (r >= 0)
 951                 fprintf(f, "TIMEZONE=%s\n", string);
 952
 953         r = sd_dhcp_lease_get_client_id(lease, &client_id, &client_id_len);
 954         if (r >= 0) {
 955                 _cleanup_free_ char *client_id_hex = NULL;
 956
 957                 client_id_hex = hexmem(client_id, client_id_len);
 958                 if (!client_id_hex) {
 959                         r = -ENOMEM;
 960                         goto fail;
 961                 }
 962                 fprintf(f, "CLIENTID=%s\n", client_id_hex);
 963         }
 964
 965         r = sd_dhcp_lease_get_vendor_specific(lease, &data, &data_len);
 966         if (r >= 0) {
 967                 _cleanup_free_ char *option_hex = NULL;
 968
 969                 option_hex = hexmem(data, data_len);
 970                 if (!option_hex) {
 971                         r = -ENOMEM;
 972                         goto fail;
 973                 }
 974                 fprintf(f, "VENDOR_SPECIFIC=%s\n", option_hex);
 975         }
 976
 977         LIST_FOREACH(options, option, lease->private_options) {
 978                 char key[STRLEN("OPTION_000")+1];
 979
 980                 xsprintf(key, "OPTION_%" PRIu8, option->tag);
 981                 r = serialize_dhcp_option(f, key, option->data, option->length);
 982                 if (r < 0)
 983                         goto fail;
 984         }
 985
 986         r = fflush_and_check(f);
 987         if (r < 0)
 988                 goto fail;
 989
 990         if (rename(temp_path, lease_file) < 0) {
 991                 r = -errno;
 992                 goto fail;
 993         }
 994
 995         return 0;
 996
 997 fail:
 998         if (temp_path)
 999                 (void) unlink(temp_path);
1000
1001         return log_error_errno(r, "Failed to save lease data %s: %m", lease_file);
1002 }
1003
1004 int dhcp_lease_load(sd_dhcp_lease **ret, const char *lease_file) {
1005
1006         _cleanup_(sd_dhcp_lease_unrefp) sd_dhcp_lease *lease = NULL;
1007         _cleanup_free_ char
1008                 *address = NULL,
1009                 *router = NULL,
1010                 *netmask = NULL,
1011                 *server_address = NULL,
1012                 *next_server = NULL,
1013                 *broadcast = NULL,
1014                 *dns = NULL,
1015                 *ntp = NULL,
1016                 *mtu = NULL,
1017                 *routes = NULL,
1018                 *domains = NULL,
1019                 *client_id_hex = NULL,
1020                 *vendor_specific_hex = NULL,
1021                 *lifetime = NULL,
1022                 *t1 = NULL,
1023                 *t2 = NULL,
1024                 *options[SD_DHCP_OPTION_PRIVATE_LAST - SD_DHCP_OPTION_PRIVATE_BASE + 1] = {};
1025
1026         int r, i;
1027
1028         assert(lease_file);
1029         assert(ret);
1030
1031         r = dhcp_lease_new(&lease);
1032         if (r < 0)
1033                 return r;
1034
1035         r = parse_env_file(NULL, lease_file, NEWLINE,
1036                            "ADDRESS", &address,
1037                            "ROUTER", &router,
1038                            "NETMASK", &netmask,
1039                            "SERVER_IDENTIFIER", &server_address,
1040                            "NEXT_SERVER", &next_server,
1041                            "BROADCAST", &broadcast,
1042                            "DNS", &dns,
1043                            "NTP", &ntp,
1044                            "MTU", &mtu,
1045                            "DOMAINNAME", &lease->domainname,
1046                            "HOSTNAME", &lease->hostname,
1047                            "DOMAIN_SEARCH_LIST", &domains,
1048                            "ROOT_PATH", &lease->root_path,
1049                            "ROUTES", &routes,
1050                            "CLIENTID", &client_id_hex,
1051                            "TIMEZONE", &lease->timezone,
1052                            "VENDOR_SPECIFIC", &vendor_specific_hex,
1053                            "LIFETIME", &lifetime,
1054                            "T1", &t1,
1055                            "T2", &t2,
1056                            "OPTION_224", &options[0],
1057                            "OPTION_225", &options[1],
1058                            "OPTION_226", &options[2],
1059                            "OPTION_227", &options[3],
1060                            "OPTION_228", &options[4],
1061                            "OPTION_229", &options[5],
1062                            "OPTION_230", &options[6],
1063                            "OPTION_231", &options[7],
1064                            "OPTION_232", &options[8],
1065                            "OPTION_233", &options[9],
1066                            "OPTION_234", &options[10],
1067                            "OPTION_235", &options[11],
1068                            "OPTION_236", &options[12],
1069                            "OPTION_237", &options[13],
1070                            "OPTION_238", &options[14],
1071                            "OPTION_239", &options[15],
1072                            "OPTION_240", &options[16],
1073                            "OPTION_241", &options[17],
1074                            "OPTION_242", &options[18],
1075                            "OPTION_243", &options[19],
1076                            "OPTION_244", &options[20],
1077                            "OPTION_245", &options[21],
1078                            "OPTION_246", &options[22],
1079                            "OPTION_247", &options[23],
1080                            "OPTION_248", &options[24],
1081                            "OPTION_249", &options[25],
1082                            "OPTION_250", &options[26],
1083                            "OPTION_251", &options[27],
1084                            "OPTION_252", &options[28],
1085                            "OPTION_253", &options[29],
1086                            "OPTION_254", &options[30],
1087                            NULL);
1088         if (r < 0)
1089                 return r;
1090
1091         if (address) {
1092                 r = inet_pton(AF_INET, address, &lease->address);
1093                 if (r <= 0)
1094                         log_debug("Failed to parse address %s, ignoring.", address);
1095         }
1096
1097         if (router) {
1098                 r = inet_pton(AF_INET, router, &lease->router);
1099                 if (r <= 0)
1100                         log_debug("Failed to parse router %s, ignoring.", router);
1101         }
1102
1103         if (netmask) {
1104                 r = inet_pton(AF_INET, netmask, &lease->subnet_mask);
1105                 if (r <= 0)
1106                         log_debug("Failed to parse netmask %s, ignoring.", netmask);
1107                 else
1108                         lease->have_subnet_mask = true;
1109         }
1110
1111         if (server_address) {
1112                 r = inet_pton(AF_INET, server_address, &lease->server_address);
1113                 if (r <= 0)
1114                         log_debug("Failed to parse server address %s, ignoring.", server_address);
1115         }
1116
1117         if (next_server) {
1118                 r = inet_pton(AF_INET, next_server, &lease->next_server);
1119                 if (r <= 0)
1120                         log_debug("Failed to parse next server %s, ignoring.", next_server);
1121         }
1122
1123         if (broadcast) {
1124                 r = inet_pton(AF_INET, broadcast, &lease->broadcast);
1125                 if (r <= 0)
1126                         log_debug("Failed to parse broadcast address %s, ignoring.", broadcast);
1127                 else
1128                         lease->have_broadcast = true;
1129         }
1130
1131         if (dns) {
1132                 r = deserialize_in_addrs(&lease->dns, dns);
1133                 if (r < 0)
1134                         log_debug_errno(r, "Failed to deserialize DNS servers %s, ignoring: %m", dns);
1135                 else
1136                         lease->dns_size = r;
1137         }
1138
1139         if (ntp) {
1140                 r = deserialize_in_addrs(&lease->ntp, ntp);
1141                 if (r < 0)
1142                         log_debug_errno(r, "Failed to deserialize NTP servers %s, ignoring: %m", ntp);
1143                 else
1144                         lease->ntp_size = r;
1145         }
1146
1147         if (mtu) {
1148                 r = safe_atou16(mtu, &lease->mtu);
1149                 if (r < 0)
1150                         log_debug_errno(r, "Failed to parse MTU %s, ignoring: %m", mtu);
1151         }
1152
1153         if (domains) {
1154                 _cleanup_strv_free_ char **a = NULL;
1155                 a = strv_split(domains, " ");
1156                 if (!a)
1157                         return -ENOMEM;
1158
1159                 if (!strv_isempty(a)) {
1160                         lease->search_domains = a;
1161                         a = NULL;
1162                 }
1163         }
1164
1165         if (routes) {
1166                 r = deserialize_dhcp_routes(
1167                                 &lease->static_route,
1168                                 &lease->static_route_size,
1169                                 &lease->static_route_allocated,
1170                                 routes);
1171                 if (r < 0)
1172                         log_debug_errno(r, "Failed to parse DHCP routes %s, ignoring: %m", routes);
1173         }
1174
1175         if (lifetime) {
1176                 r = safe_atou32(lifetime, &lease->lifetime);
1177                 if (r < 0)
1178                         log_debug_errno(r, "Failed to parse lifetime %s, ignoring: %m", lifetime);
1179         }
1180
1181         if (t1) {
1182                 r = safe_atou32(t1, &lease->t1);
1183                 if (r < 0)
1184                         log_debug_errno(r, "Failed to parse T1 %s, ignoring: %m", t1);
1185         }
1186
1187         if (t2) {
1188                 r = safe_atou32(t2, &lease->t2);
1189                 if (r < 0)
1190                         log_debug_errno(r, "Failed to parse T2 %s, ignoring: %m", t2);
1191         }
1192
1193         if (client_id_hex) {
1194                 r = unhexmem(client_id_hex, (size_t) -1, &lease->client_id, &lease->client_id_len);
1195                 if (r < 0)
1196                         log_debug_errno(r, "Failed to parse client ID %s, ignoring: %m", client_id_hex);
1197         }
1198
1199         if (vendor_specific_hex) {
1200                 r = unhexmem(vendor_specific_hex, (size_t) -1, &lease->vendor_specific, &lease->vendor_specific_len);
1201                 if (r < 0)
1202                         log_debug_errno(r, "Failed to parse vendor specific data %s, ignoring: %m", vendor_specific_hex);
1203         }
1204
1205         for (i = 0; i <= SD_DHCP_OPTION_PRIVATE_LAST - SD_DHCP_OPTION_PRIVATE_BASE; i++) {
1206                 _cleanup_free_ void *data = NULL;
1207                 size_t len;
1208
1209                 if (!options[i])
1210                         continue;
1211
1212                 r = unhexmem(options[i], (size_t) -1, &data, &len);
1213                 if (r < 0) {
1214                         log_debug_errno(r, "Failed to parse private DHCP option %s, ignoring: %m", options[i]);
1215                         continue;
1216                 }
1217
1218                 r = dhcp_lease_insert_private_option(lease, SD_DHCP_OPTION_PRIVATE_BASE + i, data, len);
1219                 if (r < 0)
1220                         return r;
1221         }
1222
1223         *ret = TAKE_PTR(lease);
1224
1225         return 0;
1226 }
1227
1228 int dhcp_lease_set_default_subnet_mask(sd_dhcp_lease *lease) {
1229         struct in_addr address, mask;
1230         int r;
1231
1232         assert(lease);
1233
1234         if (lease->address == 0)
1235                 return -ENODATA;
1236
1237         address.s_addr = lease->address;
1238
1239         /* fall back to the default subnet masks based on address class */
1240         r = in4_addr_default_subnet_mask(&address, &mask);
1241         if (r < 0)
1242                 return r;
1243
1244         lease->subnet_mask = mask.s_addr;
1245         lease->have_subnet_mask = true;
1246
1247         return 0;
1248 }
1249
1250 int sd_dhcp_lease_get_client_id(sd_dhcp_lease *lease, const void **client_id, size_t *client_id_len) {
1251         assert_return(lease, -EINVAL);
1252         assert_return(client_id, -EINVAL);
1253         assert_return(client_id_len, -EINVAL);
1254
1255         if (!lease->client_id)
1256                 return -ENODATA;
1257
1258         *client_id = lease->client_id;
1259         *client_id_len = lease->client_id_len;
1260
1261         return 0;
1262 }
1263
1264 int dhcp_lease_set_client_id(sd_dhcp_lease *lease, const void *client_id, size_t client_id_len) {
1265         assert_return(lease, -EINVAL);
1266         assert_return(client_id || client_id_len <= 0, -EINVAL);
1267
1268         if (client_id_len <= 0)
1269                 lease->client_id = mfree(lease->client_id);
1270         else {
1271                 void *p;
1272
1273                 p = memdup(client_id, client_id_len);
1274                 if (!p)
1275                         return -ENOMEM;
1276
1277                 free(lease->client_id);
1278                 lease->client_id = p;
1279                 lease->client_id_len = client_id_len;
1280         }
1281
1282         return 0;
1283 }
1284
1285 int sd_dhcp_lease_get_timezone(sd_dhcp_lease *lease, const char **tz) {
1286         assert_return(lease, -EINVAL);
1287         assert_return(tz, -EINVAL);
1288
1289         if (!lease->timezone)
1290                 return -ENODATA;
1291
1292         *tz = lease->timezone;
1293         return 0;
1294 }
1295
1296 int sd_dhcp_route_get_destination(sd_dhcp_route *route, struct in_addr *destination) {
1297         assert_return(route, -EINVAL);
1298         assert_return(destination, -EINVAL);
1299
1300         *destination = route->dst_addr;
1301         return 0;
1302 }
1303
1304 int sd_dhcp_route_get_destination_prefix_length(sd_dhcp_route *route, uint8_t *length) {
1305         assert_return(route, -EINVAL);
1306         assert_return(length, -EINVAL);
1307
1308         *length = route->dst_prefixlen;
1309         return 0;
1310 }
1311
1312 int sd_dhcp_route_get_gateway(sd_dhcp_route *route, struct in_addr *gateway) {
1313         assert_return(route, -EINVAL);
1314         assert_return(gateway, -EINVAL);
1315
1316         *gateway = route->gw_addr;
1317         return 0;
1318 }