gdhcp/client.c

   1 /*
   2  *
   3  *  DHCP client library with GLib integration
   4  *
   5  *  Copyright (C) 2009-2011  Intel Corporation. All rights reserved.
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License version 2 as
   9  *  published by the Free Software Foundation.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  *
  20  */
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #define _GNU_SOURCE
  27 #include <stdio.h>
  28 #include <errno.h>
  29 #include <unistd.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <sys/ioctl.h>
  33 #include <arpa/inet.h>
  34
  35 #include <netpacket/packet.h>
  36 #include <netinet/if_ether.h>
  37 #include <net/ethernet.h>
  38
  39 #include <linux/if.h>
  40 #include <linux/filter.h>
  41
  42 #include <glib.h>
  43
  44 #include "gdhcp.h"
  45 #include "common.h"
  46 #include "ipv4ll.h"
  47
  48 #define DISCOVER_TIMEOUT 3
  49 #define DISCOVER_RETRIES 10
  50
  51 #define REQUEST_TIMEOUT 3
  52 #define REQUEST_RETRIES 5
  53
  54 typedef enum _listen_mode {
  55         L_NONE,
  56         L2,
  57         L3,
  58         L_ARP,
  59 } ListenMode;
  60
  61 typedef enum _dhcp_client_state {
  62         INIT_SELECTING,
  63         REQUESTING,
  64         BOUND,
  65         RENEWING,
  66         REBINDING,
  67         RELEASED,
  68         IPV4LL_PROBE,
  69         IPV4LL_ANNOUNCE,
  70         IPV4LL_MONITOR,
  71         IPV4LL_DEFEND,
  72         INFORMATION_REQ,
  73         SOLICITATION,
  74         REQUEST,
  75         RENEW,
  76         REBIND,
  77         RELEASE,
  78 } ClientState;
  79
  80 struct _GDHCPClient {
  81         int ref_count;
  82         GDHCPType type;
  83         ClientState state;
  84         int ifindex;
  85         char *interface;
  86         uint8_t mac_address[6];
  87         uint32_t xid;
  88         uint32_t server_ip;
  89         uint32_t requested_ip;
  90         char *assigned_ip;
  91         time_t start;
  92         uint32_t lease_seconds;
  93         ListenMode listen_mode;
  94         int listener_sockfd;
  95         uint8_t retry_times;
  96         uint8_t ack_retry_times;
  97         uint8_t conflicts;
  98         guint timeout;
  99         guint listener_watch;
 100         GIOChannel *listener_channel;
 101         GList *require_list;
 102         GList *request_list;
 103         GHashTable *code_value_hash;
 104         GHashTable *send_value_hash;
 105         GDHCPClientEventFunc lease_available_cb;
 106         gpointer lease_available_data;
 107         GDHCPClientEventFunc ipv4ll_available_cb;
 108         gpointer ipv4ll_available_data;
 109         GDHCPClientEventFunc no_lease_cb;
 110         gpointer no_lease_data;
 111         GDHCPClientEventFunc lease_lost_cb;
 112         gpointer lease_lost_data;
 113         GDHCPClientEventFunc ipv4ll_lost_cb;
 114         gpointer ipv4ll_lost_data;
 115         GDHCPClientEventFunc address_conflict_cb;
 116         gpointer address_conflict_data;
 117         GDHCPDebugFunc debug_func;
 118         gpointer debug_data;
 119         GDHCPClientEventFunc information_req_cb;
 120         gpointer information_req_data;
 121         GDHCPClientEventFunc solicitation_cb;
 122         gpointer solicitation_data;
 123         GDHCPClientEventFunc advertise_cb;
 124         gpointer advertise_data;
 125         GDHCPClientEventFunc request_cb;
 126         gpointer request_data;
 127         GDHCPClientEventFunc renew_cb;
 128         gpointer renew_data;
 129         GDHCPClientEventFunc rebind_cb;
 130         gpointer rebind_data;
 131         GDHCPClientEventFunc release_cb;
 132         gpointer release_data;
 133         char *last_address;
 134         unsigned char *duid;
 135         int duid_len;
 136         unsigned char *server_duid;
 137         int server_duid_len;
 138         uint16_t status_code;
 139         uint32_t iaid;
 140         uint32_t T1, T2;
 141         struct in6_addr ia_na;
 142         struct in6_addr ia_ta;
 143         time_t last_renew;
 144         time_t last_rebind;
 145         time_t expire;
 146 };
 147
 148 static inline void debug(GDHCPClient *client, const char *format, ...)
 149 {
 150         char str[256];
 151         va_list ap;
 152
 153         if (client->debug_func == NULL)
 154                 return;
 155
 156         va_start(ap, format);
 157
 158         if (vsnprintf(str, sizeof(str), format, ap) > 0)
 159                 client->debug_func(str, client->debug_data);
 160
 161         va_end(ap);
 162 }
 163
 164 /* Initialize the packet with the proper defaults */
 165 static void init_packet(GDHCPClient *dhcp_client, gpointer pkt, char type)
 166 {
 167         if (dhcp_client->type == G_DHCP_IPV6)
 168                 dhcpv6_init_header(pkt, type);
 169         else {
 170                 struct dhcp_packet *packet = pkt;
 171
 172                 dhcp_init_header(packet, type);
 173                 memcpy(packet->chaddr, dhcp_client->mac_address, 6);
 174         }
 175 }
 176
 177 static void add_request_options(GDHCPClient *dhcp_client,
 178                                 struct dhcp_packet *packet)
 179 {
 180         int len = 0;
 181         GList *list;
 182         uint8_t code;
 183         int end = dhcp_end_option(packet->options);
 184
 185         for (list = dhcp_client->request_list; list; list = list->next) {
 186                 code = (uint8_t) GPOINTER_TO_INT(list->data);
 187
 188                 packet->options[end + OPT_DATA + len] = code;
 189                 len++;
 190         }
 191
 192         if (len) {
 193                 packet->options[end + OPT_CODE] = DHCP_PARAM_REQ;
 194                 packet->options[end + OPT_LEN] = len;
 195                 packet->options[end + OPT_DATA + len] = DHCP_END;
 196         }
 197 }
 198
 199 struct hash_params {
 200         unsigned char *buf;
 201         int max_buf;
 202         unsigned char **ptr_buf;
 203 };
 204
 205 static void add_dhcpv6_binary_option(gpointer key, gpointer value,
 206                                         gpointer user_data)
 207 {
 208         uint8_t *option = value;
 209         uint16_t len;
 210         struct hash_params *params = user_data;
 211
 212         /* option[0][1] contains option code */
 213         len = option[2] << 8 | option[3];
 214
 215         if ((*params->ptr_buf + len + 2 + 2) > (params->buf + params->max_buf))
 216                 return;
 217
 218         memcpy(*params->ptr_buf, option, len + 2 + 2);
 219         (*params->ptr_buf) += len + 2 + 2;
 220 }
 221
 222 static void add_dhcpv6_send_options(GDHCPClient *dhcp_client,
 223                                 unsigned char *buf, int max_buf,
 224                                 unsigned char **ptr_buf)
 225 {
 226         struct hash_params params = {
 227                 .buf = buf,
 228                 .max_buf = max_buf,
 229                 .ptr_buf = ptr_buf
 230         };
 231
 232         if (dhcp_client->type == G_DHCP_IPV4)
 233                 return;
 234
 235         g_hash_table_foreach(dhcp_client->send_value_hash,
 236                                 add_dhcpv6_binary_option, &params);
 237
 238         *ptr_buf = *params.ptr_buf;
 239 }
 240
 241 static void copy_option(uint8_t *buf, uint16_t code, uint16_t len,
 242                         uint8_t *msg)
 243 {
 244         buf[0] = code >> 8;
 245         buf[1] = code & 0xff;
 246         buf[2] = len >> 8;
 247         buf[3] = len & 0xff;
 248         if (len > 0 && msg != NULL)
 249                 memcpy(&buf[4], msg, len);
 250 }
 251
 252 static void add_dhcpv6_request_options(GDHCPClient *dhcp_client,
 253                                 struct dhcpv6_packet *packet,
 254                                 unsigned char *buf, int max_buf,
 255                                 unsigned char **ptr_buf)
 256 {
 257         GList *list;
 258         uint16_t code;
 259         int len;
 260
 261         if (dhcp_client->type == G_DHCP_IPV4)
 262                 return;
 263
 264         for (list = dhcp_client->request_list; list; list = list->next) {
 265                 code = (uint16_t) GPOINTER_TO_INT(list->data);
 266
 267                 switch (code) {
 268                 case G_DHCPV6_CLIENTID:
 269                         if (dhcp_client->duid == NULL)
 270                                 return;
 271
 272                         len = 2 + 2 + dhcp_client->duid_len;
 273                         if ((*ptr_buf + len) > (buf + max_buf)) {
 274                                 debug(dhcp_client, "Too long dhcpv6 message "
 275                                         "when writing client id option");
 276                                 return;
 277                         }
 278
 279                         copy_option(*ptr_buf, G_DHCPV6_CLIENTID,
 280                                 dhcp_client->duid_len, dhcp_client->duid);
 281                         (*ptr_buf) += len;
 282                         break;
 283
 284                 case G_DHCPV6_SERVERID:
 285                         if (dhcp_client->server_duid == NULL)
 286                                 return;
 287
 288                         len = 2 + 2 + dhcp_client->server_duid_len;
 289                         if ((*ptr_buf + len) > (buf + max_buf)) {
 290                                 debug(dhcp_client, "Too long dhcpv6 message "
 291                                         "when writing server id option");
 292                                 return;
 293                         }
 294
 295                         copy_option(*ptr_buf, G_DHCPV6_SERVERID,
 296                                 dhcp_client->server_duid_len,
 297                                 dhcp_client->server_duid);
 298                         (*ptr_buf) += len;
 299                         break;
 300
 301                 case G_DHCPV6_RAPID_COMMIT:
 302                         len = 2 + 2;
 303                         if ((*ptr_buf + len) > (buf + max_buf)) {
 304                                 debug(dhcp_client, "Too long dhcpv6 message "
 305                                         "when writing rapid commit option");
 306                                 return;
 307                         }
 308
 309                         copy_option(*ptr_buf, G_DHCPV6_RAPID_COMMIT, 0, 0);
 310                         (*ptr_buf) += len;
 311                         break;
 312
 313                 case G_DHCPV6_ORO:
 314                         break;
 315
 316                 case G_DHCPV6_DNS_SERVERS:
 317                         break;
 318
 319                 case G_DHCPV6_SNTP_SERVERS:
 320                         break;
 321
 322                 default:
 323                         break;
 324                 }
 325         }
 326 }
 327
 328 static void add_binary_option(gpointer key, gpointer value, gpointer user_data)
 329 {
 330         uint8_t *option = value;
 331         struct dhcp_packet *packet = user_data;
 332
 333         dhcp_add_binary_option(packet, option);
 334 }
 335
 336 static void add_send_options(GDHCPClient *dhcp_client,
 337                                 struct dhcp_packet *packet)
 338 {
 339         g_hash_table_foreach(dhcp_client->send_value_hash,
 340                                 add_binary_option, packet);
 341 }
 342
 343 /*
 344  * Return an RFC 951- and 2131-complaint BOOTP 'secs' value that
 345  * represents the number of seconds elapsed from the start of
 346  * attempting DHCP to satisfy some DHCP servers that allow for an
 347  * "authoritative" reply before responding.
 348  */
 349 static uint16_t dhcp_attempt_secs(GDHCPClient *dhcp_client)
 350 {
 351         return htons(MIN(time(NULL) - dhcp_client->start, UINT16_MAX));
 352 }
 353
 354 static int send_discover(GDHCPClient *dhcp_client, uint32_t requested)
 355 {
 356         struct dhcp_packet packet;
 357
 358         debug(dhcp_client, "sending DHCP discover request");
 359
 360         init_packet(dhcp_client, &packet, DHCPDISCOVER);
 361
 362         packet.xid = dhcp_client->xid;
 363         packet.secs = dhcp_attempt_secs(dhcp_client);
 364
 365         if (requested)
 366                 dhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested);
 367
 368         /* Explicitly saying that we want RFC-compliant packets helps
 369          * some buggy DHCP servers to NOT send bigger packets */
 370         dhcp_add_simple_option(&packet, DHCP_MAX_SIZE, htons(576));
 371
 372         add_request_options(dhcp_client, &packet);
 373
 374         add_send_options(dhcp_client, &packet);
 375
 376         return dhcp_send_raw_packet(&packet, INADDR_ANY, CLIENT_PORT,
 377                                         INADDR_BROADCAST, SERVER_PORT,
 378                                         MAC_BCAST_ADDR, dhcp_client->ifindex);
 379 }
 380
 381 static int send_select(GDHCPClient *dhcp_client)
 382 {
 383         struct dhcp_packet packet;
 384
 385         debug(dhcp_client, "sending DHCP select request");
 386
 387         init_packet(dhcp_client, &packet, DHCPREQUEST);
 388
 389         packet.xid = dhcp_client->xid;
 390         packet.secs = dhcp_attempt_secs(dhcp_client);
 391
 392         dhcp_add_simple_option(&packet, DHCP_REQUESTED_IP,
 393                                         dhcp_client->requested_ip);
 394         dhcp_add_simple_option(&packet, DHCP_SERVER_ID, dhcp_client->server_ip);
 395
 396         add_request_options(dhcp_client, &packet);
 397
 398         add_send_options(dhcp_client, &packet);
 399
 400         return dhcp_send_raw_packet(&packet, INADDR_ANY, CLIENT_PORT,
 401                                         INADDR_BROADCAST, SERVER_PORT,
 402                                         MAC_BCAST_ADDR, dhcp_client->ifindex);
 403 }
 404
 405 static int send_renew(GDHCPClient *dhcp_client)
 406 {
 407         struct dhcp_packet packet;
 408
 409         debug(dhcp_client, "sending DHCP renew request");
 410
 411         init_packet(dhcp_client , &packet, DHCPREQUEST);
 412         packet.xid = dhcp_client->xid;
 413         packet.ciaddr = dhcp_client->requested_ip;
 414
 415         add_request_options(dhcp_client, &packet);
 416
 417         add_send_options(dhcp_client, &packet);
 418
 419         return dhcp_send_kernel_packet(&packet,
 420                 dhcp_client->requested_ip, CLIENT_PORT,
 421                 dhcp_client->server_ip, SERVER_PORT);
 422 }
 423
 424 static int send_rebound(GDHCPClient *dhcp_client)
 425 {
 426         struct dhcp_packet packet;
 427
 428         debug(dhcp_client, "sending DHCP rebound request");
 429
 430         init_packet(dhcp_client , &packet, DHCPREQUEST);
 431         packet.xid = dhcp_client->xid;
 432         packet.ciaddr = dhcp_client->requested_ip;
 433
 434         add_request_options(dhcp_client, &packet);
 435
 436         add_send_options(dhcp_client, &packet);
 437
 438         return dhcp_send_raw_packet(&packet, INADDR_ANY, CLIENT_PORT,
 439                                         INADDR_BROADCAST, SERVER_PORT,
 440                                         MAC_BCAST_ADDR, dhcp_client->ifindex);
 441 }
 442
 443 static int send_release(GDHCPClient *dhcp_client,
 444                         uint32_t server, uint32_t ciaddr)
 445 {
 446         struct dhcp_packet packet;
 447
 448         debug(dhcp_client, "sending DHCP release request");
 449
 450         init_packet(dhcp_client, &packet, DHCPRELEASE);
 451         packet.xid = rand();
 452         packet.ciaddr = ciaddr;
 453
 454         dhcp_add_simple_option(&packet, DHCP_SERVER_ID, server);
 455
 456         return dhcp_send_kernel_packet(&packet, ciaddr, CLIENT_PORT,
 457                                                 server, SERVER_PORT);
 458 }
 459
 460 static gboolean ipv4ll_probe_timeout(gpointer dhcp_data);
 461 static int switch_listening_mode(GDHCPClient *dhcp_client,
 462                                         ListenMode listen_mode);
 463
 464 static gboolean send_probe_packet(gpointer dhcp_data)
 465 {
 466         GDHCPClient *dhcp_client;
 467         guint timeout;
 468
 469         dhcp_client = dhcp_data;
 470         /* if requested_ip is not valid, pick a new address*/
 471         if (dhcp_client->requested_ip == 0) {
 472                 debug(dhcp_client, "pick a new random address");
 473                 dhcp_client->requested_ip = ipv4ll_random_ip(0);
 474         }
 475
 476         debug(dhcp_client, "sending IPV4LL probe request");
 477
 478         if (dhcp_client->retry_times == 1) {
 479                 dhcp_client->state = IPV4LL_PROBE;
 480                 switch_listening_mode(dhcp_client, L_ARP);
 481         }
 482         ipv4ll_send_arp_packet(dhcp_client->mac_address, 0,
 483                         dhcp_client->requested_ip, dhcp_client->ifindex);
 484
 485         if (dhcp_client->retry_times < PROBE_NUM) {
 486                 /*add a random timeout in range of PROBE_MIN to PROBE_MAX*/
 487                 timeout = ipv4ll_random_delay_ms(PROBE_MAX-PROBE_MIN);
 488                 timeout += PROBE_MIN*1000;
 489         } else
 490                 timeout = (ANNOUNCE_WAIT * 1000);
 491
 492         dhcp_client->timeout = g_timeout_add_full(G_PRIORITY_HIGH,
 493                                                  timeout,
 494                                                  ipv4ll_probe_timeout,
 495                                                  dhcp_client,
 496                                                  NULL);
 497         return FALSE;
 498 }
 499
 500 static gboolean ipv4ll_announce_timeout(gpointer dhcp_data);
 501 static gboolean ipv4ll_defend_timeout(gpointer dhcp_data);
 502
 503 static gboolean send_announce_packet(gpointer dhcp_data)
 504 {
 505         GDHCPClient *dhcp_client;
 506
 507         dhcp_client = dhcp_data;
 508
 509         debug(dhcp_client, "sending IPV4LL announce request");
 510
 511         ipv4ll_send_arp_packet(dhcp_client->mac_address,
 512                                 dhcp_client->requested_ip,
 513                                 dhcp_client->requested_ip,
 514                                 dhcp_client->ifindex);
 515
 516         if (dhcp_client->timeout > 0)
 517                 g_source_remove(dhcp_client->timeout);
 518         dhcp_client->timeout = 0;
 519
 520         if (dhcp_client->state == IPV4LL_DEFEND) {
 521                 dhcp_client->timeout =
 522                         g_timeout_add_seconds_full(G_PRIORITY_HIGH,
 523                                                 DEFEND_INTERVAL,
 524                                                 ipv4ll_defend_timeout,
 525                                                 dhcp_client,
 526                                                 NULL);
 527                 return TRUE;
 528         } else
 529                 dhcp_client->timeout =
 530                         g_timeout_add_seconds_full(G_PRIORITY_HIGH,
 531                                                 ANNOUNCE_INTERVAL,
 532                                                 ipv4ll_announce_timeout,
 533                                                 dhcp_client,
 534                                                 NULL);
 535         return TRUE;
 536 }
 537
 538 static void get_interface_mac_address(int index, uint8_t *mac_address)
 539 {
 540         struct ifreq ifr;
 541         int sk, err;
 542
 543         sk = socket(PF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
 544         if (sk < 0) {
 545                 perror("Open socket error");
 546                 return;
 547         }
 548
 549         memset(&ifr, 0, sizeof(ifr));
 550         ifr.ifr_ifindex = index;
 551
 552         err = ioctl(sk, SIOCGIFNAME, &ifr);
 553         if (err < 0) {
 554                 perror("Get interface name error");
 555                 goto done;
 556         }
 557
 558         err = ioctl(sk, SIOCGIFHWADDR, &ifr);
 559         if (err < 0) {
 560                 perror("Get mac address error");
 561                 goto done;
 562         }
 563
 564         memcpy(mac_address, ifr.ifr_hwaddr.sa_data, 6);
 565
 566 done:
 567         close(sk);
 568 }
 569
 570 int g_dhcpv6_create_duid(GDHCPDuidType duid_type, int index, int type,
 571                         unsigned char **duid, int *duid_len)
 572 {
 573         time_t duid_time;
 574
 575         switch (duid_type) {
 576         case G_DHCPV6_DUID_LLT:
 577                 *duid_len = 2 + 2 + 4 + ETH_ALEN;
 578                 *duid = g_try_malloc(*duid_len);
 579                 if (*duid == NULL)
 580                         return -ENOMEM;
 581
 582                 (*duid)[0] = 0;
 583                 (*duid)[1] = 1;
 584                 get_interface_mac_address(index, &(*duid)[2 + 2 + 4]);
 585                 (*duid)[2] = 0;
 586                 (*duid)[3] = type;
 587                 duid_time = time(NULL) - DUID_TIME_EPOCH;
 588                 (*duid)[4] = duid_time >> 24;
 589                 (*duid)[5] = duid_time >> 16;
 590                 (*duid)[6] = duid_time >> 8;
 591                 (*duid)[7] = duid_time & 0xff;
 592                 break;
 593         case G_DHCPV6_DUID_EN:
 594                 return -EINVAL;
 595         case G_DHCPV6_DUID_LL:
 596                 *duid_len = 2 + 2 + ETH_ALEN;
 597                 *duid = g_try_malloc(*duid_len);
 598                 if (*duid == NULL)
 599                         return -ENOMEM;
 600
 601                 (*duid)[0] = 0;
 602                 (*duid)[1] = 3;
 603                 get_interface_mac_address(index, &(*duid)[2 + 2]);
 604                 (*duid)[2] = 0;
 605                 (*duid)[3] = type;
 606                 break;
 607         }
 608
 609         return 0;
 610 }
 611
 612 int g_dhcpv6_client_set_duid(GDHCPClient *dhcp_client, unsigned char *duid,
 613                         int duid_len)
 614 {
 615         if (dhcp_client == NULL || dhcp_client->type == G_DHCP_IPV4)
 616                 return -EINVAL;
 617
 618         g_free(dhcp_client->duid);
 619
 620         dhcp_client->duid = duid;
 621         dhcp_client->duid_len = duid_len;
 622
 623         return 0;
 624 }
 625
 626 uint32_t g_dhcpv6_client_get_iaid(GDHCPClient *dhcp_client)
 627 {
 628         if (dhcp_client == NULL || dhcp_client->type == G_DHCP_IPV4)
 629                 return 0;
 630
 631         return dhcp_client->iaid;
 632 }
 633
 634 void g_dhcpv6_client_create_iaid(GDHCPClient *dhcp_client, int index,
 635                                 unsigned char *iaid)
 636 {
 637         uint8_t buf[6];
 638
 639         get_interface_mac_address(index, buf);
 640
 641         memcpy(iaid, &buf[2], 4);
 642         dhcp_client->iaid = iaid[0] << 24 |
 643                         iaid[1] << 16 | iaid[2] << 8 | iaid[3];
 644 }
 645
 646 int g_dhcpv6_client_get_timeouts(GDHCPClient *dhcp_client,
 647                                 uint32_t *T1, uint32_t *T2,
 648                                 time_t *last_renew, time_t *last_rebind,
 649                                 time_t *expire)
 650 {
 651         if (dhcp_client == NULL || dhcp_client->type == G_DHCP_IPV4)
 652                 return -EINVAL;
 653
 654         if (T1 != NULL)
 655                 *T1 = dhcp_client->T1;
 656
 657         if (T2 != NULL)
 658                 *T2 = dhcp_client->T2;
 659
 660         if (last_renew != NULL)
 661                 *last_renew = dhcp_client->last_renew;
 662
 663         if (last_rebind != NULL)
 664                 *last_rebind = dhcp_client->last_rebind;
 665
 666         if (expire != NULL)
 667                 *expire = dhcp_client->expire;
 668
 669         return 0;
 670 }
 671
 672 static uint8_t *create_iaaddr(GDHCPClient *dhcp_client, uint8_t *buf,
 673                                 uint16_t len)
 674 {
 675         buf[0] = 0;
 676         buf[1] = G_DHCPV6_IAADDR;
 677         buf[2] = 0;
 678         buf[3] = len;
 679         memcpy(&buf[4], &dhcp_client->ia_na, 16);
 680         memset(&buf[20], 0, 4); /* preferred */
 681         memset(&buf[24], 0, 4); /* valid */
 682         return buf;
 683 }
 684
 685 static void put_iaid(GDHCPClient *dhcp_client, int index, uint8_t *buf)
 686 {
 687         uint32_t iaid;
 688
 689         iaid = g_dhcpv6_client_get_iaid(dhcp_client);
 690         if (iaid == 0) {
 691                 g_dhcpv6_client_create_iaid(dhcp_client, index, buf);
 692                 return;
 693         }
 694
 695         buf[0] = iaid >> 24;
 696         buf[1] = iaid >> 16;
 697         buf[2] = iaid >> 8;
 698         buf[3] = iaid;
 699 }
 700
 701 int g_dhcpv6_client_set_ia(GDHCPClient *dhcp_client, int index,
 702                         int code, uint32_t *T1, uint32_t *T2,
 703                         gboolean add_iaaddr)
 704 {
 705         if (code == G_DHCPV6_IA_TA) {
 706                 uint8_t ia_options[4];
 707
 708                 put_iaid(dhcp_client, index, ia_options);
 709
 710                 g_dhcp_client_set_request(dhcp_client, G_DHCPV6_IA_TA);
 711                 g_dhcpv6_client_set_send(dhcp_client, G_DHCPV6_IA_TA,
 712                                         ia_options, sizeof(ia_options));
 713
 714         } else if (code == G_DHCPV6_IA_NA) {
 715
 716                 g_dhcp_client_set_request(dhcp_client, G_DHCPV6_IA_NA);
 717
 718                 if (add_iaaddr == TRUE) {
 719 #define IAADDR_LEN (16+4+4)
 720                         uint8_t ia_options[4+4+4+2+2+IAADDR_LEN];
 721
 722                         put_iaid(dhcp_client, index, ia_options);
 723
 724                         if (T1 != NULL) {
 725                                 ia_options[4] = *T1 >> 24;
 726                                 ia_options[5] = *T1 >> 16;
 727                                 ia_options[6] = *T1 >> 8;
 728                                 ia_options[7] = *T1;
 729                         } else
 730                                 memset(&ia_options[4], 0x00, 4);
 731
 732                         if (T2 != NULL) {
 733                                 ia_options[8] = *T2 >> 24;
 734                                 ia_options[9] = *T2 >> 16;
 735                                 ia_options[10] = *T2 >> 8;
 736                                 ia_options[11] = *T2;
 737                         } else
 738                                 memset(&ia_options[8], 0x00, 4);
 739
 740                         create_iaaddr(dhcp_client, &ia_options[12],
 741                                         IAADDR_LEN);
 742
 743                         g_dhcpv6_client_set_send(dhcp_client, G_DHCPV6_IA_NA,
 744                                         ia_options, sizeof(ia_options));
 745                 } else {
 746                         uint8_t ia_options[4+4+4];
 747
 748                         put_iaid(dhcp_client, index, ia_options);
 749
 750                         memset(&ia_options[4], 0x00, 4); /* T1 (4 bytes) */
 751                         memset(&ia_options[8], 0x00, 4); /* T2 (4 bytes) */
 752
 753                         g_dhcpv6_client_set_send(dhcp_client, G_DHCPV6_IA_NA,
 754                                         ia_options, sizeof(ia_options));
 755                 }
 756
 757         } else
 758                 return -EINVAL;
 759
 760         return 0;
 761 }
 762
 763 int g_dhcpv6_client_set_oro(GDHCPClient *dhcp_client, int args, ...)
 764 {
 765         va_list va;
 766         int i, j, len = sizeof(uint16_t) * args;
 767         uint8_t *values;
 768
 769         values = g_try_malloc(len);
 770         if (values == NULL)
 771                 return -ENOMEM;
 772
 773         va_start(va, args);
 774         for (i = 0, j = 0; i < args; i++) {
 775                 uint16_t value = va_arg(va, int);
 776                 values[j++] = value >> 8;
 777                 values[j++] = value & 0xff;
 778         }
 779         va_end(va);
 780
 781         g_dhcpv6_client_set_send(dhcp_client, G_DHCPV6_ORO, values, len);
 782
 783         return 0;
 784 }
 785
 786 static int send_dhcpv6_msg(GDHCPClient *dhcp_client, int type, char *msg)
 787 {
 788         struct dhcpv6_packet *packet;
 789         uint8_t buf[MAX_DHCPV6_PKT_SIZE];
 790         unsigned char *ptr;
 791         int ret, max_buf;
 792
 793         memset(buf, 0, sizeof(buf));
 794         packet = (struct dhcpv6_packet *)&buf[0];
 795         ptr = buf + sizeof(struct dhcpv6_packet);
 796
 797         debug(dhcp_client, "sending DHCPv6 %s message", msg);
 798
 799         init_packet(dhcp_client, packet, type);
 800
 801         dhcp_client->xid = packet->transaction_id[0] << 16 |
 802                         packet->transaction_id[1] << 8 |
 803                         packet->transaction_id[2];
 804
 805         max_buf = MAX_DHCPV6_PKT_SIZE - sizeof(struct dhcpv6_packet);
 806
 807         add_dhcpv6_request_options(dhcp_client, packet, buf, max_buf, &ptr);
 808
 809         add_dhcpv6_send_options(dhcp_client, buf, max_buf, &ptr);
 810
 811         ret = dhcpv6_send_packet(dhcp_client->ifindex, packet, ptr - buf);
 812
 813         debug(dhcp_client, "sent %d pkt %p len %d", ret, packet, ptr - buf);
 814         return ret;
 815 }
 816
 817 static int send_solicitation(GDHCPClient *dhcp_client)
 818 {
 819         return send_dhcpv6_msg(dhcp_client, DHCPV6_SOLICIT, "solicit");
 820 }
 821
 822 static int send_dhcpv6_request(GDHCPClient *dhcp_client)
 823 {
 824         return send_dhcpv6_msg(dhcp_client, DHCPV6_REQUEST, "request");
 825 }
 826
 827 static int send_dhcpv6_renew(GDHCPClient *dhcp_client)
 828 {
 829         return send_dhcpv6_msg(dhcp_client, DHCPV6_RENEW, "renew");
 830 }
 831
 832 static int send_dhcpv6_rebind(GDHCPClient *dhcp_client)
 833 {
 834         return send_dhcpv6_msg(dhcp_client, DHCPV6_REBIND, "rebind");
 835 }
 836
 837 static int send_dhcpv6_release(GDHCPClient *dhcp_client)
 838 {
 839         return send_dhcpv6_msg(dhcp_client, DHCPV6_RELEASE, "release");
 840 }
 841
 842 static int send_information_req(GDHCPClient *dhcp_client)
 843 {
 844         return send_dhcpv6_msg(dhcp_client, DHCPV6_INFORMATION_REQ,
 845                                 "information-req");
 846 }
 847
 848 static void remove_value(gpointer data, gpointer user_data)
 849 {
 850         char *value = data;
 851         g_free(value);
 852 }
 853
 854 static void remove_option_value(gpointer data)
 855 {
 856         GList *option_value = data;
 857
 858         g_list_foreach(option_value, remove_value, NULL);
 859 }
 860
 861 GDHCPClient *g_dhcp_client_new(GDHCPType type,
 862                         int ifindex, GDHCPClientError *error)
 863 {
 864         GDHCPClient *dhcp_client;
 865
 866         if (ifindex < 0) {
 867                 *error = G_DHCP_CLIENT_ERROR_INVALID_INDEX;
 868                 return NULL;
 869         }
 870
 871         dhcp_client = g_try_new0(GDHCPClient, 1);
 872         if (dhcp_client == NULL) {
 873                 *error = G_DHCP_CLIENT_ERROR_NOMEM;
 874                 return NULL;
 875         }
 876
 877         dhcp_client->interface = get_interface_name(ifindex);
 878         if (dhcp_client->interface == NULL) {
 879                 *error = G_DHCP_CLIENT_ERROR_INTERFACE_UNAVAILABLE;
 880                 goto error;
 881         }
 882
 883         if (interface_is_up(ifindex) == FALSE) {
 884                 *error = G_DHCP_CLIENT_ERROR_INTERFACE_DOWN;
 885                 goto error;
 886         }
 887
 888         get_interface_mac_address(ifindex, dhcp_client->mac_address);
 889
 890         dhcp_client->listener_sockfd = -1;
 891         dhcp_client->listener_channel = NULL;
 892         dhcp_client->listen_mode = L_NONE;
 893         dhcp_client->ref_count = 1;
 894         dhcp_client->type = type;
 895         dhcp_client->ifindex = ifindex;
 896         dhcp_client->lease_available_cb = NULL;
 897         dhcp_client->ipv4ll_available_cb = NULL;
 898         dhcp_client->no_lease_cb = NULL;
 899         dhcp_client->lease_lost_cb = NULL;
 900         dhcp_client->ipv4ll_lost_cb = NULL;
 901         dhcp_client->address_conflict_cb = NULL;
 902         dhcp_client->listener_watch = 0;
 903         dhcp_client->retry_times = 0;
 904         dhcp_client->ack_retry_times = 0;
 905         dhcp_client->code_value_hash = g_hash_table_new_full(g_direct_hash,
 906                                 g_direct_equal, NULL, remove_option_value);
 907         dhcp_client->send_value_hash = g_hash_table_new_full(g_direct_hash,
 908                                 g_direct_equal, NULL, g_free);
 909         dhcp_client->request_list = NULL;
 910         dhcp_client->require_list = NULL;
 911         dhcp_client->duid = NULL;
 912         dhcp_client->duid_len = 0;
 913         dhcp_client->last_renew = dhcp_client->last_rebind = time(NULL);
 914         dhcp_client->expire = 0;
 915
 916         *error = G_DHCP_CLIENT_ERROR_NONE;
 917
 918         return dhcp_client;
 919
 920 error:
 921         g_free(dhcp_client->interface);
 922         g_free(dhcp_client);
 923         return NULL;
 924 }
 925
 926 #define SERVER_AND_CLIENT_PORTS  ((67 << 16) + 68)
 927
 928 static int dhcp_l2_socket(int ifindex)
 929 {
 930         int fd;
 931         struct sockaddr_ll sock;
 932
 933         /*
 934          * Comment:
 935          *
 936          *      I've selected not to see LL header, so BPF doesn't see it, too.
 937          *      The filter may also pass non-IP and non-ARP packets, but we do
 938          *      a more complete check when receiving the message in userspace.
 939          *
 940          * and filter shamelessly stolen from:
 941          *
 942          *      http://www.flamewarmaster.de/software/dhcpclient/
 943          *
 944          * There are a few other interesting ideas on that page (look under
 945          * "Motivation").  Use of netlink events is most interesting.  Think
 946          * of various network servers listening for events and reconfiguring.
 947          * That would obsolete sending HUP signals and/or make use of restarts.
 948          *
 949          * Copyright: 2006, 2007 Stefan Rompf <sux@loplof.de>.
 950          * License: GPL v2.
 951          *
 952          * TODO: make conditional?
 953          */
 954         static const struct sock_filter filter_instr[] = {
 955                 /* check for udp */
 956                 BPF_STMT(BPF_LD|BPF_B|BPF_ABS, 9),
 957                 /* L5, L1, is UDP? */
 958                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, IPPROTO_UDP, 2, 0),
 959                 /* ugly check for arp on ethernet-like and IPv4 */
 960                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, 2), /* L1: */
 961                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x08000604, 3, 4),/* L3, L4 */
 962                 /* skip IP header */
 963                 BPF_STMT(BPF_LDX|BPF_B|BPF_MSH, 0), /* L5: */
 964                 /* check udp source and destination ports */
 965                 BPF_STMT(BPF_LD|BPF_W|BPF_IND, 0),
 966                 /* L3, L4 */
 967                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, SERVER_AND_CLIENT_PORTS, 0, 1),
 968                 /* returns */
 969                 BPF_STMT(BPF_RET|BPF_K, 0x0fffffff), /* L3: pass */
 970                 BPF_STMT(BPF_RET|BPF_K, 0), /* L4: reject */
 971         };
 972
 973         static const struct sock_fprog filter_prog = {
 974                 .len = sizeof(filter_instr) / sizeof(filter_instr[0]),
 975                 /* casting const away: */
 976                 .filter = (struct sock_filter *) filter_instr,
 977         };
 978
 979         fd = socket(PF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC, htons(ETH_P_IP));
 980         if (fd < 0)
 981                 return fd;
 982
 983         if (SERVER_PORT == 67 && CLIENT_PORT == 68)
 984                 /* Use only if standard ports are in use */
 985                 setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter_prog,
 986                                                         sizeof(filter_prog));
 987
 988         memset(&sock, 0, sizeof(sock));
 989         sock.sll_family = AF_PACKET;
 990         sock.sll_protocol = htons(ETH_P_IP);
 991         sock.sll_ifindex = ifindex;
 992
 993         if (bind(fd, (struct sockaddr *) &sock, sizeof(sock)) != 0) {
 994                 close(fd);
 995                 return -errno;
 996         }
 997
 998         return fd;
 999 }
1000
1001 static gboolean sanity_check(struct ip_udp_dhcp_packet *packet, int bytes)
1002 {
1003         if (packet->ip.protocol != IPPROTO_UDP)
1004                 return FALSE;
1005
1006         if (packet->ip.version != IPVERSION)
1007                 return FALSE;
1008
1009         if (packet->ip.ihl != sizeof(packet->ip) >> 2)
1010                 return FALSE;
1011
1012         if (packet->udp.dest != htons(CLIENT_PORT))
1013                 return FALSE;
1014
1015         if (ntohs(packet->udp.len) != (uint16_t)(bytes - sizeof(packet->ip)))
1016                 return FALSE;
1017
1018         return TRUE;
1019 }
1020
1021 static int dhcp_recv_l2_packet(struct dhcp_packet *dhcp_pkt, int fd)
1022 {
1023         int bytes;
1024         struct ip_udp_dhcp_packet packet;
1025         uint16_t check;
1026
1027         memset(&packet, 0, sizeof(packet));
1028
1029         bytes = read(fd, &packet, sizeof(packet));
1030         if (bytes < 0)
1031                 return -1;
1032
1033         if (bytes < (int) (sizeof(packet.ip) + sizeof(packet.udp)))
1034                 return -1;
1035
1036         if (bytes < ntohs(packet.ip.tot_len))
1037                 /* packet is bigger than sizeof(packet), we did partial read */
1038                 return -1;
1039
1040         /* ignore any extra garbage bytes */
1041         bytes = ntohs(packet.ip.tot_len);
1042
1043         if (sanity_check(&packet, bytes) == FALSE)
1044                 return -1;
1045
1046         check = packet.ip.check;
1047         packet.ip.check = 0;
1048         if (check != dhcp_checksum(&packet.ip, sizeof(packet.ip)))
1049                 return -1;
1050
1051         /* verify UDP checksum. IP header has to be modified for this */
1052         memset(&packet.ip, 0, offsetof(struct iphdr, protocol));
1053         /* ip.xx fields which are not memset: protocol, check, saddr, daddr */
1054         packet.ip.tot_len = packet.udp.len; /* yes, this is needed */
1055         check = packet.udp.check;
1056         packet.udp.check = 0;
1057         if (check && check != dhcp_checksum(&packet, bytes))
1058                 return -1;
1059
1060         memcpy(dhcp_pkt, &packet.data, bytes - (sizeof(packet.ip) +
1061                                                         sizeof(packet.udp)));
1062
1063         if (dhcp_pkt->cookie != htonl(DHCP_MAGIC))
1064                 return -1;
1065
1066         return bytes - (sizeof(packet.ip) + sizeof(packet.udp));
1067 }
1068
1069 static void ipv4ll_start(GDHCPClient *dhcp_client)
1070 {
1071         guint timeout;
1072         int seed;
1073
1074         if (dhcp_client->timeout > 0) {
1075                 g_source_remove(dhcp_client->timeout);
1076                 dhcp_client->timeout = 0;
1077         }
1078
1079         switch_listening_mode(dhcp_client, L_NONE);
1080         dhcp_client->type = G_DHCP_IPV4LL;
1081         dhcp_client->retry_times = 0;
1082         dhcp_client->requested_ip = 0;
1083
1084         /*try to start with a based mac address ip*/
1085         seed = (dhcp_client->mac_address[4] << 8 | dhcp_client->mac_address[4]);
1086         dhcp_client->requested_ip = ipv4ll_random_ip(seed);
1087
1088         /*first wait a random delay to avoid storm of arp request on boot*/
1089         timeout = ipv4ll_random_delay_ms(PROBE_WAIT);
1090
1091         dhcp_client->retry_times++;
1092         dhcp_client->timeout = g_timeout_add_full(G_PRIORITY_HIGH,
1093                                                 timeout,
1094                                                 send_probe_packet,
1095                                                 dhcp_client,
1096                                                 NULL);
1097 }
1098
1099 static void ipv4ll_stop(GDHCPClient *dhcp_client)
1100 {
1101
1102         switch_listening_mode(dhcp_client, L_NONE);
1103
1104         if (dhcp_client->timeout > 0)
1105                 g_source_remove(dhcp_client->timeout);
1106
1107         if (dhcp_client->listener_watch > 0) {
1108                 g_source_remove(dhcp_client->listener_watch);
1109                 dhcp_client->listener_watch = 0;
1110         }
1111
1112         dhcp_client->state = IPV4LL_PROBE;
1113         dhcp_client->retry_times = 0;
1114         dhcp_client->requested_ip = 0;
1115
1116         g_free(dhcp_client->assigned_ip);
1117         dhcp_client->assigned_ip = NULL;
1118 }
1119
1120 static int ipv4ll_recv_arp_packet(GDHCPClient *dhcp_client)
1121 {
1122         int bytes;
1123         struct ether_arp arp;
1124         uint32_t ip_requested;
1125         int source_conflict;
1126         int target_conflict;
1127
1128         memset(&arp, 0, sizeof(arp));
1129         bytes = 0;
1130         bytes = read(dhcp_client->listener_sockfd, &arp, sizeof(arp));
1131         if (bytes < 0)
1132                 return bytes;
1133
1134         if (arp.arp_op != htons(ARPOP_REPLY) &&
1135                         arp.arp_op != htons(ARPOP_REQUEST))
1136                 return -EINVAL;
1137
1138         ip_requested = ntohl(dhcp_client->requested_ip);
1139         source_conflict = !memcmp(arp.arp_spa, &ip_requested,
1140                                                 sizeof(ip_requested));
1141
1142         target_conflict = !memcmp(arp.arp_tpa, &ip_requested,
1143                                 sizeof(ip_requested));
1144
1145         if (!source_conflict && !target_conflict)
1146                 return 0;
1147
1148         dhcp_client->conflicts++;
1149
1150         debug(dhcp_client, "IPV4LL conflict detected");
1151
1152         if (dhcp_client->state == IPV4LL_MONITOR) {
1153                 if (!source_conflict)
1154                         return 0;
1155                 dhcp_client->state = IPV4LL_DEFEND;
1156                 debug(dhcp_client, "DEFEND mode conflicts : %d",
1157                         dhcp_client->conflicts);
1158                 /*Try to defend with a single announce*/
1159                 send_announce_packet(dhcp_client);
1160                 return 0;
1161         }
1162
1163         if (dhcp_client->state == IPV4LL_DEFEND) {
1164                 if (!source_conflict)
1165                         return 0;
1166                 else if (dhcp_client->ipv4ll_lost_cb != NULL)
1167                         dhcp_client->ipv4ll_lost_cb(dhcp_client,
1168                                                 dhcp_client->ipv4ll_lost_data);
1169         }
1170
1171         ipv4ll_stop(dhcp_client);
1172
1173         if (dhcp_client->conflicts < MAX_CONFLICTS) {
1174                 /*restart whole state machine*/
1175                 dhcp_client->retry_times++;
1176                 dhcp_client->timeout =
1177                         g_timeout_add_full(G_PRIORITY_HIGH,
1178                                         ipv4ll_random_delay_ms(PROBE_WAIT),
1179                                         send_probe_packet,
1180                                         dhcp_client,
1181                                         NULL);
1182         }
1183         /* Here we got a lot of conflicts, RFC3927 states that we have
1184          * to wait RATE_LIMIT_INTERVAL before retrying,
1185          * but we just report failure.
1186          */
1187         else if (dhcp_client->no_lease_cb != NULL)
1188                         dhcp_client->no_lease_cb(dhcp_client,
1189                                                 dhcp_client->no_lease_data);
1190
1191         return 0;
1192 }
1193
1194 static gboolean check_package_owner(GDHCPClient *dhcp_client, gpointer pkt)
1195 {
1196         if (dhcp_client->type == G_DHCP_IPV6) {
1197                 struct dhcpv6_packet *packet6 = pkt;
1198                 uint32_t xid;
1199
1200                 if (packet6 == NULL)
1201                         return FALSE;
1202
1203                 xid = packet6->transaction_id[0] << 16 |
1204                         packet6->transaction_id[1] << 8 |
1205                         packet6->transaction_id[2];
1206
1207                 if (xid != dhcp_client->xid)
1208                         return FALSE;
1209         } else {
1210                 struct dhcp_packet *packet = pkt;
1211
1212                 if (packet->xid != dhcp_client->xid)
1213                         return FALSE;
1214
1215                 if (packet->hlen != 6)
1216                         return FALSE;
1217
1218                 if (memcmp(packet->chaddr, dhcp_client->mac_address, 6))
1219                         return FALSE;
1220         }
1221
1222         return TRUE;
1223 }
1224
1225 static void start_request(GDHCPClient *dhcp_client);
1226
1227 static gboolean request_timeout(gpointer user_data)
1228 {
1229         GDHCPClient *dhcp_client = user_data;
1230
1231         debug(dhcp_client, "request timeout (retries %d)",
1232                                         dhcp_client->retry_times);
1233
1234         dhcp_client->retry_times++;
1235
1236         start_request(dhcp_client);
1237
1238         return FALSE;
1239 }
1240
1241 static gboolean listener_event(GIOChannel *channel, GIOCondition condition,
1242                                                         gpointer user_data);
1243
1244 static int switch_listening_mode(GDHCPClient *dhcp_client,
1245                                         ListenMode listen_mode)
1246 {
1247         GIOChannel *listener_channel;
1248         int listener_sockfd;
1249
1250         if (dhcp_client->listen_mode == listen_mode)
1251                 return 0;
1252
1253         debug(dhcp_client, "switch listening mode (%d ==> %d)",
1254                                 dhcp_client->listen_mode, listen_mode);
1255
1256         if (dhcp_client->listen_mode != L_NONE) {
1257                 if (dhcp_client->listener_watch > 0)
1258                         g_source_remove(dhcp_client->listener_watch);
1259                 dhcp_client->listener_channel = NULL;
1260                 dhcp_client->listen_mode = L_NONE;
1261                 dhcp_client->listener_sockfd = -1;
1262                 dhcp_client->listener_watch = 0;
1263         }
1264
1265         if (listen_mode == L_NONE)
1266                 return 0;
1267
1268         if (listen_mode == L2)
1269                 listener_sockfd = dhcp_l2_socket(dhcp_client->ifindex);
1270         else if (listen_mode == L3) {
1271                 if (dhcp_client->type == G_DHCP_IPV6)
1272                         listener_sockfd = dhcp_l3_socket(DHCPV6_CLIENT_PORT,
1273                                                         dhcp_client->interface,
1274                                                         AF_INET6);
1275                 else
1276                         listener_sockfd = dhcp_l3_socket(CLIENT_PORT,
1277                                                         dhcp_client->interface,
1278                                                         AF_INET);
1279         } else if (listen_mode == L_ARP)
1280                 listener_sockfd = ipv4ll_arp_socket(dhcp_client->ifindex);
1281         else
1282                 return -EIO;
1283
1284         if (listener_sockfd < 0)
1285                 return -EIO;
1286
1287         listener_channel = g_io_channel_unix_new(listener_sockfd);
1288         if (listener_channel == NULL) {
1289                 /* Failed to create listener channel */
1290                 close(listener_sockfd);
1291                 return -EIO;
1292         }
1293
1294         dhcp_client->listen_mode = listen_mode;
1295         dhcp_client->listener_sockfd = listener_sockfd;
1296         dhcp_client->listener_channel = listener_channel;
1297
1298         g_io_channel_set_close_on_unref(listener_channel, TRUE);
1299         dhcp_client->listener_watch =
1300                         g_io_add_watch_full(listener_channel, G_PRIORITY_HIGH,
1301                                 G_IO_IN | G_IO_NVAL | G_IO_ERR | G_IO_HUP,
1302                                                 listener_event, dhcp_client,
1303                                                                 NULL);
1304         g_io_channel_unref(dhcp_client->listener_channel);
1305
1306         return 0;
1307 }
1308
1309 static void start_request(GDHCPClient *dhcp_client)
1310 {
1311         debug(dhcp_client, "start request (retries %d)",
1312                                         dhcp_client->retry_times);
1313
1314         if (dhcp_client->retry_times == REQUEST_RETRIES) {
1315                 dhcp_client->state = INIT_SELECTING;
1316                 ipv4ll_start(dhcp_client);
1317
1318                 return;
1319         }
1320
1321         if (dhcp_client->retry_times == 0) {
1322                 dhcp_client->state = REQUESTING;
1323                 switch_listening_mode(dhcp_client, L2);
1324         }
1325
1326         send_select(dhcp_client);
1327
1328         dhcp_client->timeout = g_timeout_add_seconds_full(G_PRIORITY_HIGH,
1329                                                         REQUEST_TIMEOUT,
1330                                                         request_timeout,
1331                                                         dhcp_client,
1332                                                         NULL);
1333 }
1334
1335 static uint32_t get_lease(struct dhcp_packet *packet)
1336 {
1337         uint8_t *option_u8;
1338         uint32_t lease_seconds;
1339
1340         option_u8 = dhcp_get_option(packet, DHCP_LEASE_TIME);
1341         if (option_u8 == NULL)
1342                 return 3600;
1343
1344         lease_seconds = dhcp_get_unaligned((uint32_t *) option_u8);
1345         lease_seconds = ntohl(lease_seconds);
1346         /* paranoia: must not be prone to overflows */
1347         lease_seconds &= 0x0fffffff;
1348         if (lease_seconds < 10)
1349                 lease_seconds = 10;
1350
1351         return lease_seconds;
1352 }
1353
1354 static void restart_dhcp(GDHCPClient *dhcp_client, int retry_times)
1355 {
1356         debug(dhcp_client, "restart DHCP (retries %d)", retry_times);
1357
1358         if (dhcp_client->timeout > 0) {
1359                 g_source_remove(dhcp_client->timeout);
1360                 dhcp_client->timeout = 0;
1361         }
1362
1363         dhcp_client->retry_times = retry_times;
1364         dhcp_client->requested_ip = 0;
1365         switch_listening_mode(dhcp_client, L2);
1366
1367         g_dhcp_client_start(dhcp_client, dhcp_client->last_address);
1368 }
1369
1370 static gboolean start_rebound_timeout(gpointer user_data)
1371 {
1372         GDHCPClient *dhcp_client = user_data;
1373
1374         debug(dhcp_client, "start rebound timeout");
1375
1376         switch_listening_mode(dhcp_client, L2);
1377
1378         dhcp_client->lease_seconds >>= 1;
1379
1380         /* We need to have enough time to receive ACK package*/
1381         if (dhcp_client->lease_seconds <= 6) {
1382
1383                 /* ip need to be cleared */
1384                 if (dhcp_client->lease_lost_cb != NULL)
1385                         dhcp_client->lease_lost_cb(dhcp_client,
1386                                         dhcp_client->lease_lost_data);
1387
1388                 restart_dhcp(dhcp_client, 0);
1389         } else {
1390                 send_rebound(dhcp_client);
1391
1392                 dhcp_client->timeout =
1393                                 g_timeout_add_seconds_full(G_PRIORITY_HIGH,
1394                                                 dhcp_client->lease_seconds >> 1,
1395                                                         start_rebound_timeout,
1396                                                                 dhcp_client,
1397                                                                 NULL);
1398         }
1399
1400         return FALSE;
1401 }
1402
1403 static void start_rebound(GDHCPClient *dhcp_client)
1404 {
1405         debug(dhcp_client, "start rebound");
1406
1407         dhcp_client->state = REBINDING;
1408
1409         dhcp_client->timeout = g_timeout_add_seconds_full(G_PRIORITY_HIGH,
1410                                                 dhcp_client->lease_seconds >> 1,
1411                                                         start_rebound_timeout,
1412                                                                 dhcp_client,
1413                                                                 NULL);
1414 }
1415
1416 static gboolean start_renew_timeout(gpointer user_data)
1417 {
1418         GDHCPClient *dhcp_client = user_data;
1419
1420         debug(dhcp_client, "start renew timeout");
1421
1422         dhcp_client->state = RENEWING;
1423
1424         dhcp_client->lease_seconds >>= 1;
1425
1426         switch_listening_mode(dhcp_client, L3);
1427         if (dhcp_client->lease_seconds <= 60)
1428                 start_rebound(dhcp_client);
1429         else {
1430                 send_renew(dhcp_client);
1431
1432                 if (dhcp_client->timeout > 0)
1433                         g_source_remove(dhcp_client->timeout);
1434
1435                 dhcp_client->timeout =
1436                                 g_timeout_add_seconds_full(G_PRIORITY_HIGH,
1437                                                 dhcp_client->lease_seconds >> 1,
1438                                                         start_renew_timeout,
1439                                                                 dhcp_client,
1440                                                                 NULL);
1441         }
1442
1443         return FALSE;
1444 }
1445
1446 static void start_bound(GDHCPClient *dhcp_client)
1447 {
1448         debug(dhcp_client, "start bound");
1449
1450         dhcp_client->state = BOUND;
1451
1452         if (dhcp_client->timeout > 0)
1453                 g_source_remove(dhcp_client->timeout);
1454
1455         dhcp_client->timeout = g_timeout_add_seconds_full(G_PRIORITY_HIGH,
1456                                         dhcp_client->lease_seconds >> 1,
1457                                         start_renew_timeout, dhcp_client,
1458                                                         NULL);
1459 }
1460
1461 static gboolean restart_dhcp_timeout(gpointer user_data)
1462 {
1463         GDHCPClient *dhcp_client = user_data;
1464
1465         debug(dhcp_client, "restart DHCP timeout");
1466
1467         dhcp_client->ack_retry_times++;
1468
1469         restart_dhcp(dhcp_client, dhcp_client->ack_retry_times);
1470
1471         return FALSE;
1472 }
1473
1474 static char *get_ip(uint32_t ip)
1475 {
1476         struct in_addr addr;
1477
1478         addr.s_addr = ip;
1479
1480         return g_strdup(inet_ntoa(addr));
1481 }
1482
1483 /* get a rough idea of how long an option will be */
1484 static const uint8_t len_of_option_as_string[] = {
1485         [OPTION_IP] = sizeof("255.255.255.255 "),
1486         [OPTION_STRING] = 1,
1487         [OPTION_U8] = sizeof("255 "),
1488         [OPTION_U16] = sizeof("65535 "),
1489         [OPTION_U32] = sizeof("4294967295 "),
1490 };
1491
1492 static int sprint_nip(char *dest, const char *pre, const uint8_t *ip)
1493 {
1494         return sprintf(dest, "%s%u.%u.%u.%u", pre, ip[0], ip[1], ip[2], ip[3]);
1495 }
1496
1497 /* Create "opt_value1 option_value2 ..." string */
1498 static char *malloc_option_value_string(uint8_t *option, GDHCPOptionType type)
1499 {
1500         unsigned upper_length;
1501         int len, optlen;
1502         char *dest, *ret;
1503
1504         len = option[OPT_LEN - OPT_DATA];
1505         type &= OPTION_TYPE_MASK;
1506         optlen = dhcp_option_lengths[type];
1507         if (optlen == 0)
1508                 return NULL;
1509         upper_length = len_of_option_as_string[type] *
1510                         ((unsigned)len / (unsigned)optlen);
1511         dest = ret = malloc(upper_length + 1);
1512         if (ret == NULL)
1513                 return NULL;
1514
1515         while (len >= optlen) {
1516                 switch (type) {
1517                 case OPTION_IP:
1518                         dest += sprint_nip(dest, "", option);
1519                         break;
1520                 case OPTION_U16: {
1521                         uint16_t val_u16 = dhcp_get_unaligned(
1522                                                 (uint16_t *) option);
1523                         dest += sprintf(dest, "%u", ntohs(val_u16));
1524                         break;
1525                 }
1526                 case OPTION_U32: {
1527                         uint32_t val_u32 = dhcp_get_unaligned(
1528                                                 (uint32_t *) option);
1529                         dest += sprintf(dest, type == OPTION_U32 ? "%lu" :
1530                                         "%ld", (unsigned long) ntohl(val_u32));
1531                         break;
1532                 }
1533                 case OPTION_STRING:
1534                         memcpy(dest, option, len);
1535                         dest[len] = '\0';
1536                         return ret;
1537                 default:
1538                         break;
1539                 }
1540                 option += optlen;
1541                 len -= optlen;
1542                 if (len <= 0)
1543                         break;
1544                 *dest++ = ' ';
1545                 *dest = '\0';
1546         }
1547
1548         return ret;
1549 }
1550
1551 static GList *get_option_value_list(char *value, GDHCPOptionType type)
1552 {
1553         char *pos = value;
1554         GList *list = NULL;
1555
1556         if (pos == NULL)
1557                 return NULL;
1558
1559         if (type == OPTION_STRING)
1560                 return g_list_append(list, g_strdup(value));
1561
1562         while ((pos = strchr(pos, ' ')) != NULL) {
1563                 *pos = '\0';
1564
1565                 list = g_list_append(list, g_strdup(value));
1566
1567                 value = ++pos;
1568         }
1569
1570         list = g_list_append(list, g_strdup(value));
1571
1572         return list;
1573 }
1574
1575 static inline uint32_t get_uint32(unsigned char *value)
1576 {
1577         return value[0] << 24 | value[1] << 16 |
1578                 value[2] << 8 | value[3];
1579 }
1580
1581 static inline uint16_t get_uint16(unsigned char *value)
1582 {
1583         return value[0] << 8 | value[1];
1584 }
1585
1586 static GList *get_addresses(GDHCPClient *dhcp_client,
1587                                 int code, int len,
1588                                 unsigned char *value,
1589                                 uint16_t *status)
1590 {
1591         GList *list = NULL;
1592         struct in6_addr addr;
1593         uint32_t iaid, T1 = 0, T2 = 0, preferred = 0, valid = 0;
1594         uint16_t option_len, option_code, st = 0, max_len;
1595         int addr_count = 0, i, pos;
1596         uint8_t *option;
1597         char *str;
1598
1599         iaid = get_uint32(&value[0]);
1600         if (dhcp_client->iaid != iaid)
1601                 return NULL;
1602
1603         if (code == G_DHCPV6_IA_NA) {
1604                 T1 = get_uint32(&value[4]);
1605                 T2 = get_uint32(&value[8]);
1606
1607                 if (T1 > T2)
1608                         /* RFC 3315, 22.4 */
1609                         return NULL;
1610
1611                 pos = 12;
1612         } else
1613                 pos = 4;
1614
1615         if (len <= pos)
1616                 return NULL;
1617
1618         max_len = len - pos;
1619
1620         /* We have more sub-options in this packet. */
1621         do {
1622                 option = dhcpv6_get_sub_option(&value[pos], max_len,
1623                                         &option_code, &option_len);
1624
1625                 debug(dhcp_client, "pos %d option %p code %d len %d",
1626                         pos, option, option_code, option_len);
1627
1628                 if (option == NULL)
1629                         break;
1630
1631                 if (pos >= max_len)
1632                         break;
1633
1634                 switch (option_code) {
1635                 case G_DHCPV6_IAADDR:
1636                         i = 0;
1637                         memcpy(&addr, &option[0], sizeof(addr));
1638                         i += sizeof(addr);
1639                         preferred = get_uint32(&option[i]);
1640                         i += 4;
1641                         valid = get_uint32(&option[i]);
1642
1643                         addr_count++;
1644                         break;
1645
1646                 case G_DHCPV6_STATUS_CODE:
1647                         st = get_uint16(&option[0]);
1648                         debug(dhcp_client, "error code %d", st);
1649                         if (option_len > 2) {
1650                                 str = g_strndup((gchar *)&option[2],
1651                                                 option_len - 2);
1652                                 debug(dhcp_client, "error text: %s", str);
1653                                 g_free(str);
1654                         }
1655
1656                         *status = st;
1657                         break;
1658                 }
1659
1660                 pos += 2 + 2 + option_len;
1661
1662         } while (option != NULL);
1663
1664         if (addr_count > 0 && st == 0) {
1665                 /* We only support one address atm */
1666                 char str[INET6_ADDRSTRLEN + 1];
1667
1668                 if (preferred > valid)
1669                         /* RFC 3315, 22.6 */
1670                         return NULL;
1671
1672                 dhcp_client->T1 = T1;
1673                 dhcp_client->T2 = T2;
1674
1675                 inet_ntop(AF_INET6, &addr, str, INET6_ADDRSTRLEN);
1676                 debug(dhcp_client, "count %d addr %s T1 %u T2 %u",
1677                         addr_count, str, T1, T2);
1678
1679                 list = g_list_append(list, g_strdup(str));
1680
1681                 if (code == G_DHCPV6_IA_NA)
1682                         memcpy(&dhcp_client->ia_na, &addr,
1683                                                 sizeof(struct in6_addr));
1684                 else
1685                         memcpy(&dhcp_client->ia_ta, &addr,
1686                                                 sizeof(struct in6_addr));
1687
1688                 g_dhcpv6_client_set_expire(dhcp_client, valid);
1689         }
1690
1691         return list;
1692 }
1693
1694 static GList *get_dhcpv6_option_value_list(GDHCPClient *dhcp_client,
1695                                         int code, int len,
1696                                         unsigned char *value,
1697                                         uint16_t *status)
1698 {
1699         GList *list = NULL;
1700         char *str;
1701         int i;
1702
1703         switch (code) {
1704         case G_DHCPV6_DNS_SERVERS:      /* RFC 3646, chapter 3 */
1705         case G_DHCPV6_SNTP_SERVERS:     /* RFC 4075, chapter 4 */
1706                 if (len % 16) {
1707                         debug(dhcp_client,
1708                                 "%s server list length (%d) is invalid",
1709                                 code == G_DHCPV6_DNS_SERVERS ? "DNS" : "SNTP",
1710                                 len);
1711                         return NULL;
1712                 }
1713                 for (i = 0; i < len; i += 16) {
1714
1715                         str = g_try_malloc0(INET6_ADDRSTRLEN+1);
1716                         if (str == NULL)
1717                                 return list;
1718
1719                         if (inet_ntop(AF_INET6, &value[i], str,
1720                                         INET6_ADDRSTRLEN) == NULL)
1721                                 g_free(str);
1722                         else
1723                                 list = g_list_append(list, str);
1724                 }
1725                 break;
1726
1727         case G_DHCPV6_IA_NA:            /* RFC 3315, chapter 22.4 */
1728         case G_DHCPV6_IA_TA:            /* RFC 3315, chapter 22.5 */
1729                 list = get_addresses(dhcp_client, code, len, value, status);
1730                 break;
1731
1732         default:
1733                 break;
1734         }
1735
1736         return list;
1737 }
1738
1739 static void get_dhcpv6_request(GDHCPClient *dhcp_client,
1740                                 struct dhcpv6_packet *packet,
1741                                 uint16_t pkt_len, uint16_t *status)
1742 {
1743         GList *list, *value_list;
1744         uint8_t *option;
1745         uint16_t code;
1746         uint16_t option_len;
1747
1748         for (list = dhcp_client->request_list; list; list = list->next) {
1749                 code = (uint16_t) GPOINTER_TO_INT(list->data);
1750
1751                 option = dhcpv6_get_option(packet, pkt_len, code, &option_len,
1752                                                 NULL);
1753                 if (option == NULL) {
1754                         g_hash_table_remove(dhcp_client->code_value_hash,
1755                                                 GINT_TO_POINTER((int) code));
1756                         continue;
1757                 }
1758
1759                 value_list = get_dhcpv6_option_value_list(dhcp_client, code,
1760                                                 option_len, option, status);
1761
1762                 debug(dhcp_client, "code %d %p len %d list %p", code, option,
1763                         option_len, value_list);
1764
1765                 if (value_list == NULL)
1766                         g_hash_table_remove(dhcp_client->code_value_hash,
1767                                                 GINT_TO_POINTER((int) code));
1768                 else
1769                         g_hash_table_insert(dhcp_client->code_value_hash,
1770                                 GINT_TO_POINTER((int) code), value_list);
1771         }
1772 }
1773
1774 static void get_request(GDHCPClient *dhcp_client, struct dhcp_packet *packet)
1775 {
1776         GDHCPOptionType type;
1777         GList *list, *value_list;
1778         char *option_value;
1779         uint8_t *option;
1780         uint8_t code;
1781
1782         for (list = dhcp_client->request_list; list; list = list->next) {
1783                 code = (uint8_t) GPOINTER_TO_INT(list->data);
1784
1785                 option = dhcp_get_option(packet, code);
1786                 if (option == NULL) {
1787                         g_hash_table_remove(dhcp_client->code_value_hash,
1788                                                 GINT_TO_POINTER((int) code));
1789                         continue;
1790                 }
1791
1792                 type =  dhcp_get_code_type(code);
1793
1794                 option_value = malloc_option_value_string(option, type);
1795                 if (option_value == NULL)
1796                         g_hash_table_remove(dhcp_client->code_value_hash,
1797                                                 GINT_TO_POINTER((int) code));
1798
1799                 value_list = get_option_value_list(option_value, type);
1800
1801                 g_free(option_value);
1802
1803                 if (value_list == NULL)
1804                         g_hash_table_remove(dhcp_client->code_value_hash,
1805                                                 GINT_TO_POINTER((int) code));
1806                 else
1807                         g_hash_table_insert(dhcp_client->code_value_hash,
1808                                 GINT_TO_POINTER((int) code), value_list);
1809         }
1810 }
1811
1812 static gboolean listener_event(GIOChannel *channel, GIOCondition condition,
1813                                                         gpointer user_data)
1814 {
1815         GDHCPClient *dhcp_client = user_data;
1816         struct dhcp_packet packet;
1817         struct dhcpv6_packet *packet6 = NULL;
1818         uint8_t *message_type = NULL, *client_id = NULL, *option_u8,
1819                 *server_id = NULL;
1820         uint16_t option_len = 0, status = 0;
1821         gpointer pkt;
1822         unsigned char buf[MAX_DHCPV6_PKT_SIZE];
1823         uint16_t pkt_len = 0;
1824         int count;
1825         int re;
1826
1827         if (condition & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) {
1828                 dhcp_client->listener_watch = 0;
1829                 return FALSE;
1830         }
1831
1832         if (dhcp_client->listen_mode == L_NONE)
1833                 return FALSE;
1834
1835         pkt = &packet;
1836
1837         if (dhcp_client->listen_mode == L2)
1838                 re = dhcp_recv_l2_packet(&packet,
1839                                         dhcp_client->listener_sockfd);
1840         else if (dhcp_client->listen_mode == L3) {
1841                 if (dhcp_client->type == G_DHCP_IPV6) {
1842                         re = dhcpv6_recv_l3_packet(&packet6, buf, sizeof(buf),
1843                                                 dhcp_client->listener_sockfd);
1844                         pkt_len = re;
1845                         pkt = packet6;
1846                 } else
1847                         re = dhcp_recv_l3_packet(&packet,
1848                                                 dhcp_client->listener_sockfd);
1849         } else if (dhcp_client->listen_mode == L_ARP) {
1850                 re = ipv4ll_recv_arp_packet(dhcp_client);
1851                 return TRUE;
1852         }
1853         else
1854                 re = -EIO;
1855
1856         if (re < 0)
1857                 return TRUE;
1858
1859         if (check_package_owner(dhcp_client, pkt) == FALSE)
1860                 return TRUE;
1861
1862         if (dhcp_client->type == G_DHCP_IPV6) {
1863                 count = 0;
1864                 client_id = dhcpv6_get_option(packet6, pkt_len,
1865                                 G_DHCPV6_CLIENTID, &option_len, &count);
1866
1867                 if (client_id == NULL || count == 0 || option_len == 0 ||
1868                                 memcmp(dhcp_client->duid, client_id,
1869                                         dhcp_client->duid_len) != 0) {
1870                         debug(dhcp_client,
1871                                 "client duid error, discarding msg %p/%d/%d",
1872                                 client_id, option_len, count);
1873                         return TRUE;
1874                 }
1875
1876                 option_u8 = dhcpv6_get_option(packet6, pkt_len,
1877                                 G_DHCPV6_STATUS_CODE, &option_len, NULL);
1878                 if (option_u8 != 0 && option_len > 0) {
1879                         status = option_u8[0]<<8 | option_u8[1];
1880                         if (status != 0) {
1881                                 debug(dhcp_client, "error code %d", status);
1882                                 if (option_len > 2) {
1883                                         gchar *txt = g_strndup(
1884                                                 (gchar *)&option_u8[2],
1885                                                 option_len - 2);
1886                                         debug(dhcp_client, "error text: %s",
1887                                                 txt);
1888                                         g_free(txt);
1889                                 }
1890                         }
1891                         dhcp_client->status_code = status;
1892                 } else
1893                         dhcp_client->status_code = 0;
1894
1895         } else
1896                 message_type = dhcp_get_option(&packet, DHCP_MESSAGE_TYPE);
1897
1898         if (message_type == NULL && client_id == NULL)
1899                 /* No message type / client id option, ignore package */
1900                 return TRUE;
1901
1902         debug(dhcp_client, "received DHCP packet (current state %d)",
1903                                                         dhcp_client->state);
1904
1905         switch (dhcp_client->state) {
1906         case INIT_SELECTING:
1907                 if (*message_type != DHCPOFFER)
1908                         return TRUE;
1909
1910                 g_source_remove(dhcp_client->timeout);
1911                 dhcp_client->timeout = 0;
1912                 dhcp_client->retry_times = 0;
1913
1914                 option_u8 = dhcp_get_option(&packet, DHCP_SERVER_ID);
1915                 dhcp_client->server_ip =
1916                                 dhcp_get_unaligned((uint32_t *) option_u8);
1917                 dhcp_client->requested_ip = packet.yiaddr;
1918
1919                 dhcp_client->state = REQUESTING;
1920
1921                 start_request(dhcp_client);
1922
1923                 return TRUE;
1924         case REQUESTING:
1925         case RENEWING:
1926         case REBINDING:
1927                 if (*message_type == DHCPACK) {
1928                         dhcp_client->retry_times = 0;
1929
1930                         if (dhcp_client->timeout > 0)
1931                                 g_source_remove(dhcp_client->timeout);
1932                         dhcp_client->timeout = 0;
1933
1934                         dhcp_client->lease_seconds = get_lease(&packet);
1935
1936                         get_request(dhcp_client, &packet);
1937
1938                         switch_listening_mode(dhcp_client, L_NONE);
1939
1940                         g_free(dhcp_client->assigned_ip);
1941                         dhcp_client->assigned_ip = get_ip(packet.yiaddr);
1942
1943                         /* Address should be set up here */
1944                         if (dhcp_client->lease_available_cb != NULL)
1945                                 dhcp_client->lease_available_cb(dhcp_client,
1946                                         dhcp_client->lease_available_data);
1947
1948                         start_bound(dhcp_client);
1949                 } else if (*message_type == DHCPNAK) {
1950                         dhcp_client->retry_times = 0;
1951
1952                         if (dhcp_client->timeout > 0)
1953                                 g_source_remove(dhcp_client->timeout);
1954
1955                         dhcp_client->timeout = g_timeout_add_seconds_full(
1956                                                         G_PRIORITY_HIGH, 3,
1957                                                         restart_dhcp_timeout,
1958                                                         dhcp_client,
1959                                                         NULL);
1960                 }
1961
1962                 break;
1963         case SOLICITATION:
1964                 if (dhcp_client->type != G_DHCP_IPV6)
1965                         return TRUE;
1966
1967                 if (packet6->message != DHCPV6_REPLY &&
1968                                 packet6->message != DHCPV6_ADVERTISE)
1969                         return TRUE;
1970
1971                 count = 0;
1972                 server_id = dhcpv6_get_option(packet6, pkt_len,
1973                                 G_DHCPV6_SERVERID, &option_len, &count);
1974                 if (server_id == NULL || count != 1 || option_len == 0) {
1975                         /* RFC 3315, 15.10 */
1976                         debug(dhcp_client,
1977                                 "server duid error, discarding msg %p/%d/%d",
1978                                 server_id, option_len, count);
1979                         return TRUE;
1980                 }
1981                 dhcp_client->server_duid = g_try_malloc(option_len);
1982                 if (dhcp_client->server_duid == NULL)
1983                         return TRUE;
1984                 memcpy(dhcp_client->server_duid, server_id, option_len);
1985                 dhcp_client->server_duid_len = option_len;
1986
1987                 if (packet6->message == DHCPV6_REPLY) {
1988                         uint8_t *rapid_commit;
1989                         count = 0;
1990                         option_len = 0;
1991                         rapid_commit = dhcpv6_get_option(packet6, pkt_len,
1992                                                         G_DHCPV6_RAPID_COMMIT,
1993                                                         &option_len, &count);
1994                         if (rapid_commit == NULL || option_len == 0 ||
1995                                                                 count != 1)
1996                                 /* RFC 3315, 17.1.4 */
1997                                 return TRUE;
1998                 }
1999
2000                 switch_listening_mode(dhcp_client, L_NONE);
2001
2002                 if (dhcp_client->status_code == 0)
2003                         get_dhcpv6_request(dhcp_client, packet6, pkt_len,
2004                                         &dhcp_client->status_code);
2005
2006                 if (packet6->message == DHCPV6_ADVERTISE) {
2007                         if (dhcp_client->advertise_cb != NULL)
2008                                 dhcp_client->advertise_cb(dhcp_client,
2009                                                 dhcp_client->advertise_data);
2010                         return TRUE;
2011                 }
2012
2013                 if (dhcp_client->solicitation_cb != NULL) {
2014                         /*
2015                          * The dhcp_client might not be valid after the
2016                          * callback call so just return immediately.
2017                          */
2018                         dhcp_client->solicitation_cb(dhcp_client,
2019                                         dhcp_client->solicitation_data);
2020                         return TRUE;
2021                 }
2022                 break;
2023         case INFORMATION_REQ:
2024         case REQUEST:
2025         case RENEW:
2026         case REBIND:
2027         case RELEASE:
2028                 if (dhcp_client->type != G_DHCP_IPV6)
2029                         return TRUE;
2030
2031                 if (packet6->message != DHCPV6_REPLY)
2032                         return TRUE;
2033
2034                 count = 0;
2035                 option_len = 0;
2036                 server_id = dhcpv6_get_option(packet6, pkt_len,
2037                                 G_DHCPV6_SERVERID, &option_len, &count);
2038                 if (server_id == NULL || count != 1 || option_len == 0 ||
2039                                 (dhcp_client->server_duid_len > 0 &&
2040                                 memcmp(dhcp_client->server_duid, server_id,
2041                                         dhcp_client->server_duid_len) != 0)) {
2042                         /* RFC 3315, 15.10 */
2043                         debug(dhcp_client,
2044                                 "server duid error, discarding msg %p/%d/%d",
2045                                 server_id, option_len, count);
2046                         return TRUE;
2047                 }
2048
2049                 switch_listening_mode(dhcp_client, L_NONE);
2050
2051                 dhcp_client->status_code = 0;
2052                 get_dhcpv6_request(dhcp_client, packet6, pkt_len,
2053                                                 &dhcp_client->status_code);
2054
2055                 if (dhcp_client->information_req_cb != NULL) {
2056                         /*
2057                          * The dhcp_client might not be valid after the
2058                          * callback call so just return immediately.
2059                          */
2060                         dhcp_client->information_req_cb(dhcp_client,
2061                                         dhcp_client->information_req_data);
2062                         return TRUE;
2063                 }
2064                 if (dhcp_client->request_cb != NULL) {
2065                         dhcp_client->request_cb(dhcp_client,
2066                                         dhcp_client->request_data);
2067                         return TRUE;
2068                 }
2069                 if (dhcp_client->renew_cb != NULL) {
2070                         dhcp_client->renew_cb(dhcp_client,
2071                                         dhcp_client->renew_data);
2072                         return TRUE;
2073                 }
2074                 if (dhcp_client->rebind_cb != NULL) {
2075                         dhcp_client->rebind_cb(dhcp_client,
2076                                         dhcp_client->rebind_data);
2077                         return TRUE;
2078                 }
2079                 if (dhcp_client->release_cb != NULL) {
2080                         dhcp_client->release_cb(dhcp_client,
2081                                         dhcp_client->release_data);
2082                         return TRUE;
2083                 }
2084                 break;
2085         default:
2086                 break;
2087         }
2088
2089         debug(dhcp_client, "processed DHCP packet (new state %d)",
2090                                                         dhcp_client->state);
2091
2092         return TRUE;
2093 }
2094
2095 static gboolean discover_timeout(gpointer user_data)
2096 {
2097         GDHCPClient *dhcp_client = user_data;
2098
2099         dhcp_client->retry_times++;
2100
2101         /*
2102          * We do not send the REQUESTED IP option if we are retrying because
2103          * if the server is non-authoritative it will ignore the request if the
2104          * option is present.
2105          */
2106         g_dhcp_client_start(dhcp_client, NULL);
2107
2108         return FALSE;
2109 }
2110
2111 static gboolean ipv4ll_defend_timeout(gpointer dhcp_data)
2112 {
2113         GDHCPClient *dhcp_client = dhcp_data;
2114
2115         debug(dhcp_client, "back to MONITOR mode");
2116
2117         dhcp_client->conflicts = 0;
2118         dhcp_client->state = IPV4LL_MONITOR;
2119
2120         return FALSE;
2121 }
2122
2123 static gboolean ipv4ll_announce_timeout(gpointer dhcp_data)
2124 {
2125         GDHCPClient *dhcp_client = dhcp_data;
2126         uint32_t ip;
2127
2128         debug(dhcp_client, "request timeout (retries %d)",
2129                dhcp_client->retry_times);
2130
2131         if (dhcp_client->retry_times != ANNOUNCE_NUM){
2132                 dhcp_client->retry_times++;
2133                 send_announce_packet(dhcp_client);
2134                 return FALSE;
2135         }
2136
2137         ip = htonl(dhcp_client->requested_ip);
2138         debug(dhcp_client, "switching to monitor mode");
2139         dhcp_client->state = IPV4LL_MONITOR;
2140         dhcp_client->assigned_ip = get_ip(ip);
2141
2142         if (dhcp_client->ipv4ll_available_cb != NULL)
2143                 dhcp_client->ipv4ll_available_cb(dhcp_client,
2144                                         dhcp_client->ipv4ll_available_data);
2145         dhcp_client->conflicts = 0;
2146
2147         return FALSE;
2148 }
2149
2150 static gboolean ipv4ll_probe_timeout(gpointer dhcp_data)
2151 {
2152
2153         GDHCPClient *dhcp_client = dhcp_data;
2154
2155         debug(dhcp_client, "IPV4LL probe timeout (retries %d)",
2156                dhcp_client->retry_times);
2157
2158         if (dhcp_client->retry_times == PROBE_NUM) {
2159                 dhcp_client->state = IPV4LL_ANNOUNCE;
2160                 dhcp_client->retry_times = 0;
2161
2162                 dhcp_client->retry_times++;
2163                 send_announce_packet(dhcp_client);
2164                 return FALSE;
2165         }
2166         dhcp_client->retry_times++;
2167         send_probe_packet(dhcp_client);
2168
2169         return FALSE;
2170 }
2171
2172 int g_dhcp_client_start(GDHCPClient *dhcp_client, const char *last_address)
2173 {
2174         int re;
2175         uint32_t addr;
2176
2177         if (dhcp_client->type == G_DHCP_IPV6) {
2178                 if (dhcp_client->information_req_cb) {
2179                         dhcp_client->state = INFORMATION_REQ;
2180                         re = switch_listening_mode(dhcp_client, L3);
2181                         if (re != 0) {
2182                                 switch_listening_mode(dhcp_client, L_NONE);
2183                                 dhcp_client->state = 0;
2184                                 return re;
2185                         }
2186                         send_information_req(dhcp_client);
2187
2188                 } else if (dhcp_client->solicitation_cb) {
2189                         dhcp_client->state = SOLICITATION;
2190                         re = switch_listening_mode(dhcp_client, L3);
2191                         if (re != 0) {
2192                                 switch_listening_mode(dhcp_client, L_NONE);
2193                                 dhcp_client->state = 0;
2194                                 return re;
2195                         }
2196                         send_solicitation(dhcp_client);
2197
2198                 } else if (dhcp_client->request_cb) {
2199                         dhcp_client->state = REQUEST;
2200                         re = switch_listening_mode(dhcp_client, L3);
2201                         if (re != 0) {
2202                                 switch_listening_mode(dhcp_client, L_NONE);
2203                                 dhcp_client->state = 0;
2204                                 return re;
2205                         }
2206                         send_dhcpv6_request(dhcp_client);
2207
2208                 } else if (dhcp_client->renew_cb) {
2209                         dhcp_client->state = RENEW;
2210                         re = switch_listening_mode(dhcp_client, L3);
2211                         if (re != 0) {
2212                                 switch_listening_mode(dhcp_client, L_NONE);
2213                                 dhcp_client->state = 0;
2214                                 return re;
2215                         }
2216                         send_dhcpv6_renew(dhcp_client);
2217
2218                 } else if (dhcp_client->rebind_cb) {
2219                         dhcp_client->state = REBIND;
2220                         re = switch_listening_mode(dhcp_client, L3);
2221                         if (re != 0) {
2222                                 switch_listening_mode(dhcp_client, L_NONE);
2223                                 dhcp_client->state = 0;
2224                                 return re;
2225                         }
2226                         send_dhcpv6_rebind(dhcp_client);
2227
2228                 } else if (dhcp_client->release_cb) {
2229                         dhcp_client->state = RENEW;
2230                         re = switch_listening_mode(dhcp_client, L3);
2231                         if (re != 0) {
2232                                 switch_listening_mode(dhcp_client, L_NONE);
2233                                 dhcp_client->state = 0;
2234                                 return re;
2235                         }
2236                         send_dhcpv6_release(dhcp_client);
2237                 }
2238
2239                 return 0;
2240         }
2241
2242         if (dhcp_client->retry_times == DISCOVER_RETRIES) {
2243                 ipv4ll_start(dhcp_client);
2244                 return 0;
2245         }
2246
2247         if (dhcp_client->retry_times == 0) {
2248                 g_free(dhcp_client->assigned_ip);
2249                 dhcp_client->assigned_ip = NULL;
2250
2251                 dhcp_client->state = INIT_SELECTING;
2252                 re = switch_listening_mode(dhcp_client, L2);
2253                 if (re != 0)
2254                         return re;
2255
2256                 dhcp_client->xid = rand();
2257                 dhcp_client->start = time(NULL);
2258         }
2259
2260         if (last_address == NULL) {
2261                 addr = 0;
2262         } else {
2263                 addr = inet_addr(last_address);
2264                 if (addr == 0xFFFFFFFF) {
2265                         addr = 0;
2266                 } else {
2267                         g_free(dhcp_client->last_address);
2268                         dhcp_client->last_address = g_strdup(last_address);
2269                 }
2270         }
2271         send_discover(dhcp_client, addr);
2272
2273         dhcp_client->timeout = g_timeout_add_seconds_full(G_PRIORITY_HIGH,
2274                                                         DISCOVER_TIMEOUT,
2275                                                         discover_timeout,
2276                                                         dhcp_client,
2277                                                         NULL);
2278         return 0;
2279 }
2280
2281 void g_dhcp_client_stop(GDHCPClient *dhcp_client)
2282 {
2283         switch_listening_mode(dhcp_client, L_NONE);
2284
2285         if (dhcp_client->state == BOUND ||
2286                         dhcp_client->state == RENEWING ||
2287                                 dhcp_client->state == REBINDING)
2288                 send_release(dhcp_client, dhcp_client->server_ip,
2289                                         dhcp_client->requested_ip);
2290
2291         if (dhcp_client->timeout > 0) {
2292                 g_source_remove(dhcp_client->timeout);
2293                 dhcp_client->timeout = 0;
2294         }
2295
2296         if (dhcp_client->listener_watch > 0) {
2297                 g_source_remove(dhcp_client->listener_watch);
2298                 dhcp_client->listener_watch = 0;
2299         }
2300
2301         dhcp_client->listener_channel = NULL;
2302
2303         dhcp_client->retry_times = 0;
2304         dhcp_client->ack_retry_times = 0;
2305
2306         dhcp_client->requested_ip = 0;
2307         dhcp_client->state = RELEASED;
2308         dhcp_client->lease_seconds = 0;
2309 }
2310
2311 GList *g_dhcp_client_get_option(GDHCPClient *dhcp_client,
2312                                         unsigned char option_code)
2313 {
2314         return g_hash_table_lookup(dhcp_client->code_value_hash,
2315                                         GINT_TO_POINTER((int) option_code));
2316 }
2317
2318 void g_dhcp_client_register_event(GDHCPClient *dhcp_client,
2319                                         GDHCPClientEvent event,
2320                                         GDHCPClientEventFunc func,
2321                                                         gpointer data)
2322 {
2323         switch (event) {
2324         case G_DHCP_CLIENT_EVENT_LEASE_AVAILABLE:
2325                 dhcp_client->lease_available_cb = func;
2326                 dhcp_client->lease_available_data = data;
2327                 return;
2328         case G_DHCP_CLIENT_EVENT_IPV4LL_AVAILABLE:
2329                 if (dhcp_client->type == G_DHCP_IPV6)
2330                         return;
2331                 dhcp_client->ipv4ll_available_cb = func;
2332                 dhcp_client->ipv4ll_available_data = data;
2333                 return;
2334         case G_DHCP_CLIENT_EVENT_NO_LEASE:
2335                 dhcp_client->no_lease_cb = func;
2336                 dhcp_client->no_lease_data = data;
2337                 return;
2338         case G_DHCP_CLIENT_EVENT_LEASE_LOST:
2339                 dhcp_client->lease_lost_cb = func;
2340                 dhcp_client->lease_lost_data = data;
2341                 return;
2342         case G_DHCP_CLIENT_EVENT_IPV4LL_LOST:
2343                 if (dhcp_client->type == G_DHCP_IPV6)
2344                         return;
2345                 dhcp_client->ipv4ll_lost_cb = func;
2346                 dhcp_client->ipv4ll_lost_data = data;
2347                 return;
2348         case G_DHCP_CLIENT_EVENT_ADDRESS_CONFLICT:
2349                 dhcp_client->address_conflict_cb = func;
2350                 dhcp_client->address_conflict_data = data;
2351                 return;
2352         case G_DHCP_CLIENT_EVENT_INFORMATION_REQ:
2353                 if (dhcp_client->type == G_DHCP_IPV4)
2354                         return;
2355                 dhcp_client->information_req_cb = func;
2356                 dhcp_client->information_req_data = data;
2357                 return;
2358         case G_DHCP_CLIENT_EVENT_SOLICITATION:
2359                 if (dhcp_client->type == G_DHCP_IPV4)
2360                         return;
2361                 dhcp_client->solicitation_cb = func;
2362                 dhcp_client->solicitation_data = data;
2363                 return;
2364         case G_DHCP_CLIENT_EVENT_ADVERTISE:
2365                 if (dhcp_client->type == G_DHCP_IPV4)
2366                         return;
2367                 dhcp_client->advertise_cb = func;
2368                 dhcp_client->advertise_data = data;
2369                 return;
2370         case G_DHCP_CLIENT_EVENT_REQUEST:
2371                 if (dhcp_client->type == G_DHCP_IPV4)
2372                         return;
2373                 dhcp_client->request_cb = func;
2374                 dhcp_client->request_data = data;
2375                 return;
2376         case G_DHCP_CLIENT_EVENT_RENEW:
2377                 if (dhcp_client->type == G_DHCP_IPV4)
2378                         return;
2379                 dhcp_client->renew_cb = func;
2380                 dhcp_client->renew_data = data;
2381                 return;
2382         case G_DHCP_CLIENT_EVENT_REBIND:
2383                 if (dhcp_client->type == G_DHCP_IPV4)
2384                         return;
2385                 dhcp_client->rebind_cb = func;
2386                 dhcp_client->rebind_data = data;
2387                 return;
2388         case G_DHCP_CLIENT_EVENT_RELEASE:
2389                 if (dhcp_client->type == G_DHCP_IPV4)
2390                         return;
2391                 dhcp_client->release_cb = func;
2392                 dhcp_client->release_data = data;
2393                 return;
2394         }
2395 }
2396
2397 int g_dhcp_client_get_index(GDHCPClient *dhcp_client)
2398 {
2399         return dhcp_client->ifindex;
2400 }
2401
2402 char *g_dhcp_client_get_address(GDHCPClient *dhcp_client)
2403 {
2404         return g_strdup(dhcp_client->assigned_ip);
2405 }
2406
2407 char *g_dhcp_client_get_netmask(GDHCPClient *dhcp_client)
2408 {
2409         GList *option = NULL;
2410
2411         if (dhcp_client->type == G_DHCP_IPV6)
2412                 return NULL;
2413
2414         switch (dhcp_client->state) {
2415         case IPV4LL_DEFEND:
2416         case IPV4LL_MONITOR:
2417                 return g_strdup("255.255.0.0");
2418         case BOUND:
2419         case RENEWING:
2420         case REBINDING:
2421                 option = g_dhcp_client_get_option(dhcp_client, G_DHCP_SUBNET);
2422                 if (option != NULL)
2423                         return g_strdup(option->data);
2424         case INIT_SELECTING:
2425         case REQUESTING:
2426         case RELEASED:
2427         case IPV4LL_PROBE:
2428         case IPV4LL_ANNOUNCE:
2429         case INFORMATION_REQ:
2430         case SOLICITATION:
2431         case REQUEST:
2432         case RENEW:
2433         case REBIND:
2434         case RELEASE:
2435                 break;
2436         }
2437         return NULL;
2438 }
2439
2440 GDHCPClientError g_dhcp_client_set_request(GDHCPClient *dhcp_client,
2441                                                 unsigned int option_code)
2442 {
2443         if (g_list_find(dhcp_client->request_list,
2444                         GINT_TO_POINTER((int) option_code)) == NULL)
2445                 dhcp_client->request_list = g_list_prepend(
2446                                         dhcp_client->request_list,
2447                                         (GINT_TO_POINTER((int) option_code)));
2448
2449         return G_DHCP_CLIENT_ERROR_NONE;
2450 }
2451
2452 void g_dhcp_client_clear_requests(GDHCPClient *dhcp_client)
2453 {
2454         g_list_free(dhcp_client->request_list);
2455         dhcp_client->request_list = NULL;
2456 }
2457
2458 void g_dhcp_client_clear_values(GDHCPClient *dhcp_client)
2459 {
2460         g_hash_table_remove_all(dhcp_client->send_value_hash);
2461 }
2462
2463 static uint8_t *alloc_dhcp_option(int code, const uint8_t *data, unsigned size)
2464 {
2465         uint8_t *storage;
2466
2467         storage = g_try_malloc(size + OPT_DATA);
2468         if (storage == NULL)
2469                 return NULL;
2470
2471         storage[OPT_CODE] = code;
2472         storage[OPT_LEN] = size;
2473         memcpy(&storage[OPT_DATA], data, size);
2474
2475         return storage;
2476 }
2477
2478 static uint8_t *alloc_dhcp_data_option(int code, const uint8_t *data, unsigned size)
2479 {
2480         return alloc_dhcp_option(code, data, MIN(size, 255));
2481 }
2482
2483 static uint8_t *alloc_dhcp_string_option(int code, const char *str)
2484 {
2485         return alloc_dhcp_data_option(code, (const uint8_t *)str, strlen(str));
2486 }
2487
2488 GDHCPClientError g_dhcp_client_set_id(GDHCPClient *dhcp_client)
2489 {
2490         const unsigned maclen = 6;
2491         const unsigned idlen = maclen + 1;
2492         const uint8_t option_code = G_DHCP_CLIENT_ID;
2493         uint8_t idbuf[idlen];
2494         uint8_t *data_option;
2495
2496         idbuf[0] = ARPHRD_ETHER;
2497
2498         memcpy(&idbuf[1], dhcp_client->mac_address, maclen);
2499
2500         data_option = alloc_dhcp_data_option(option_code, idbuf, idlen);
2501         if (data_option == NULL)
2502                 return G_DHCP_CLIENT_ERROR_NOMEM;
2503
2504         g_hash_table_insert(dhcp_client->send_value_hash,
2505                 GINT_TO_POINTER((int) option_code), data_option);
2506
2507         return G_DHCP_CLIENT_ERROR_NONE;
2508 }
2509
2510 /* Now only support send hostname */
2511 GDHCPClientError g_dhcp_client_set_send(GDHCPClient *dhcp_client,
2512                 unsigned char option_code, const char *option_value)
2513 {
2514         uint8_t *binary_option;
2515
2516         if (option_code == G_DHCP_HOST_NAME && option_value != NULL) {
2517                 binary_option = alloc_dhcp_string_option(option_code,
2518                                                         option_value);
2519                 if (binary_option == NULL)
2520                         return G_DHCP_CLIENT_ERROR_NOMEM;
2521
2522                 g_hash_table_insert(dhcp_client->send_value_hash,
2523                         GINT_TO_POINTER((int) option_code), binary_option);
2524         }
2525
2526         return G_DHCP_CLIENT_ERROR_NONE;
2527 }
2528
2529 static uint8_t *alloc_dhcpv6_option(uint16_t code, uint8_t *option,
2530                                 uint16_t len)
2531 {
2532         uint8_t *storage;
2533
2534         storage = g_malloc(2 + 2 + len);
2535         if (storage == NULL)
2536                 return NULL;
2537
2538         storage[0] = code >> 8;
2539         storage[1] = code & 0xff;
2540         storage[2] = len >> 8;
2541         storage[3] = len & 0xff;
2542         memcpy(storage + 2 + 2, option, len);
2543
2544         return storage;
2545 }
2546
2547 void g_dhcpv6_client_set_send(GDHCPClient *dhcp_client,
2548                                         uint16_t option_code,
2549                                         uint8_t *option_value,
2550                                         uint16_t option_len)
2551 {
2552         if (option_value != NULL) {
2553                 uint8_t *binary_option;
2554
2555                 debug(dhcp_client, "setting option %d to %p len %d",
2556                         option_code, option_value, option_len);
2557
2558                 binary_option = alloc_dhcpv6_option(option_code, option_value,
2559                                                 option_len);
2560                 if (binary_option != NULL)
2561                         g_hash_table_insert(dhcp_client->send_value_hash,
2562                                         GINT_TO_POINTER((int) option_code),
2563                                         binary_option);
2564         }
2565 }
2566
2567 void g_dhcpv6_client_reset_renew(GDHCPClient *dhcp_client)
2568 {
2569         if (dhcp_client == NULL || dhcp_client->type == G_DHCP_IPV4)
2570                 return;
2571
2572         dhcp_client->last_renew = time(NULL);
2573 }
2574
2575 void g_dhcpv6_client_reset_rebind(GDHCPClient *dhcp_client)
2576 {
2577         if (dhcp_client == NULL || dhcp_client->type == G_DHCP_IPV4)
2578                 return;
2579
2580         dhcp_client->last_rebind = time(NULL);
2581 }
2582
2583 void g_dhcpv6_client_set_expire(GDHCPClient *dhcp_client, uint32_t timeout)
2584 {
2585         if (dhcp_client == NULL || dhcp_client->type == G_DHCP_IPV4)
2586                 return;
2587
2588         dhcp_client->expire = time(NULL) + timeout;
2589 }
2590
2591 uint16_t g_dhcpv6_client_get_status(GDHCPClient *dhcp_client)
2592 {
2593         if (dhcp_client == NULL || dhcp_client->type == G_DHCP_IPV4)
2594                 return 0;
2595
2596         return dhcp_client->status_code;
2597 }
2598
2599 GDHCPClient *g_dhcp_client_ref(GDHCPClient *dhcp_client)
2600 {
2601         if (dhcp_client == NULL)
2602                 return NULL;
2603
2604         __sync_fetch_and_add(&dhcp_client->ref_count, 1);
2605
2606         return dhcp_client;
2607 }
2608
2609 void g_dhcp_client_unref(GDHCPClient *dhcp_client)
2610 {
2611         if (dhcp_client == NULL)
2612                 return;
2613
2614         if (__sync_fetch_and_sub(&dhcp_client->ref_count, 1) != 1)
2615                 return;
2616
2617         g_dhcp_client_stop(dhcp_client);
2618
2619         g_free(dhcp_client->interface);
2620         g_free(dhcp_client->assigned_ip);
2621         g_free(dhcp_client->last_address);
2622         g_free(dhcp_client->duid);
2623         g_free(dhcp_client->server_duid);
2624
2625         g_list_free(dhcp_client->request_list);
2626         g_list_free(dhcp_client->require_list);
2627
2628         g_hash_table_destroy(dhcp_client->code_value_hash);
2629         g_hash_table_destroy(dhcp_client->send_value_hash);
2630
2631         g_free(dhcp_client);
2632 }
2633
2634 void g_dhcp_client_set_debug(GDHCPClient *dhcp_client,
2635                                 GDHCPDebugFunc func, gpointer user_data)
2636 {
2637         if (dhcp_client == NULL)
2638                 return;
2639
2640         dhcp_client->debug_func = func;
2641         dhcp_client->debug_data = user_data;
2642 }