2 This file is part of systemd.
4 Copyright (C) 2013 Intel Corporation. All rights reserved.
6 systemd is free software; you can redistribute it and/or modify it
7 under the terms of the GNU Lesser General Public License as published by
8 the Free Software Foundation; either version 2.1 of the License, or
9 (at your option) any later version.
11 systemd is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public License
17 along with systemd; If not, see <http://www.gnu.org/licenses/>.
24 #include <net/ethernet.h>
25 #include <net/if_arp.h>
26 #include <sys/param.h>
27 #include <sys/ioctl.h>
33 #include "dhcp-protocol.h"
34 #include "dhcp-internal.h"
35 #include "dhcp-lease-internal.h"
36 #include "sd-dhcp-client.h"
38 struct sd_dhcp_client {
44 sd_event_source *timeout_resend;
47 union sockaddr_union link;
48 sd_event_source *receive_message;
50 size_t req_opts_allocated;
55 struct ether_addr mac_addr;
62 sd_event_source *timeout_t1;
63 sd_event_source *timeout_t2;
64 sd_event_source *timeout_expire;
65 sd_dhcp_client_cb_t cb;
70 static const uint8_t default_req_opts[] = {
71 DHCP_OPTION_SUBNET_MASK,
73 DHCP_OPTION_HOST_NAME,
74 DHCP_OPTION_DOMAIN_NAME,
75 DHCP_OPTION_DOMAIN_NAME_SERVER,
76 DHCP_OPTION_NTP_SERVER,
79 static int client_receive_message_raw(sd_event_source *s, int fd,
80 uint32_t revents, void *userdata);
81 static int client_receive_message_udp(sd_event_source *s, int fd,
82 uint32_t revents, void *userdata);
83 static sd_dhcp_client *client_stop(sd_dhcp_client *client, int error);
85 int sd_dhcp_client_set_callback(sd_dhcp_client *client, sd_dhcp_client_cb_t cb,
87 assert_return(client, -EINVAL);
90 client->userdata = userdata;
95 int sd_dhcp_client_set_request_option(sd_dhcp_client *client, uint8_t option) {
98 assert_return(client, -EINVAL);
99 assert_return (client->state == DHCP_STATE_INIT, -EBUSY);
102 case DHCP_OPTION_PAD:
103 case DHCP_OPTION_OVERLOAD:
104 case DHCP_OPTION_MESSAGE_TYPE:
105 case DHCP_OPTION_PARAMETER_REQUEST_LIST:
106 case DHCP_OPTION_END:
113 for (i = 0; i < client->req_opts_size; i++)
114 if (client->req_opts[i] == option)
117 if (!GREEDY_REALLOC(client->req_opts, client->req_opts_allocated,
118 client->req_opts_size + 1))
121 client->req_opts[client->req_opts_size++] = option;
126 int sd_dhcp_client_set_request_address(sd_dhcp_client *client,
127 const struct in_addr *last_addr) {
128 assert_return(client, -EINVAL);
129 assert_return(client->state == DHCP_STATE_INIT, -EBUSY);
132 client->last_addr = last_addr->s_addr;
134 client->last_addr = INADDR_ANY;
139 int sd_dhcp_client_set_index(sd_dhcp_client *client, int interface_index) {
140 assert_return(client, -EINVAL);
141 assert_return(client->state == DHCP_STATE_INIT, -EBUSY);
142 assert_return(interface_index >= -1, -EINVAL);
144 client->index = interface_index;
149 int sd_dhcp_client_set_mac(sd_dhcp_client *client,
150 const struct ether_addr *addr) {
151 bool need_restart = false;
153 assert_return(client, -EINVAL);
154 assert_return(addr, -EINVAL);
156 if (memcmp(&client->client_id.mac_addr, addr, ETH_ALEN) == 0)
159 if (client->state != DHCP_STATE_INIT) {
160 log_dhcp_client(client, "Changing MAC address on running DHCP "
161 "client, restarting");
163 client = client_stop(client, DHCP_EVENT_STOP);
169 memcpy(&client->client_id.mac_addr, addr, ETH_ALEN);
170 client->client_id.type = 0x01;
173 sd_dhcp_client_start(client);
178 int sd_dhcp_client_get_lease(sd_dhcp_client *client, sd_dhcp_lease **ret) {
179 assert_return(client, -EINVAL);
180 assert_return(ret, -EINVAL);
182 if (client->state != DHCP_STATE_BOUND &&
183 client->state != DHCP_STATE_RENEWING &&
184 client->state != DHCP_STATE_REBINDING)
185 return -EADDRNOTAVAIL;
187 *ret = sd_dhcp_lease_ref(client->lease);
192 static sd_dhcp_client *client_notify(sd_dhcp_client *client, int event) {
194 client = sd_dhcp_client_ref(client);
195 client->cb(client, event, client->userdata);
196 client = sd_dhcp_client_unref(client);
202 static int client_initialize(sd_dhcp_client *client) {
203 assert_return(client, -EINVAL);
205 client->receive_message =
206 sd_event_source_unref(client->receive_message);
208 client->fd = safe_close(client->fd);
210 client->timeout_resend = sd_event_source_unref(client->timeout_resend);
212 client->timeout_t1 = sd_event_source_unref(client->timeout_t1);
213 client->timeout_t2 = sd_event_source_unref(client->timeout_t2);
214 client->timeout_expire = sd_event_source_unref(client->timeout_expire);
218 client->state = DHCP_STATE_INIT;
222 client->lease = sd_dhcp_lease_unref(client->lease);
227 static sd_dhcp_client *client_stop(sd_dhcp_client *client, int error) {
228 assert_return(client, NULL);
230 log_dhcp_client(client, "STOPPED %d", error);
232 client = client_notify(client, error);
235 client_initialize(client);
240 static int client_message_init(sd_dhcp_client *client, DHCPMessage *message,
241 uint8_t type, uint8_t **opt, size_t *optlen) {
245 assert(client->secs);
250 r = dhcp_message_init(message, BOOTREQUEST, client->xid, type, opt,
255 /* Although 'secs' field is a SHOULD in RFC 2131, certain DHCP servers
256 refuse to issue an DHCP lease if 'secs' is set to zero */
257 message->secs = htobe16(client->secs);
259 memcpy(&message->chaddr, &client->client_id.mac_addr, ETH_ALEN);
261 if (client->state == DHCP_STATE_RENEWING ||
262 client->state == DHCP_STATE_REBINDING)
263 message->ciaddr = client->lease->address;
265 /* Some DHCP servers will refuse to issue an DHCP lease if the Client
266 Identifier option is not set */
267 r = dhcp_option_append(opt, optlen, DHCP_OPTION_CLIENT_IDENTIFIER,
268 sizeof(client->client_id), &client->client_id);
272 if (type == DHCP_DISCOVER || type == DHCP_REQUEST) {
275 r = dhcp_option_append(opt, optlen,
276 DHCP_OPTION_PARAMETER_REQUEST_LIST,
277 client->req_opts_size,
282 /* Some DHCP servers will send bigger DHCP packets than the
283 defined default size unless the Maximum Messge Size option
284 is explicitely set */
285 max_size = htobe16(DHCP_IP_UDP_SIZE + DHCP_MESSAGE_SIZE +
286 DHCP_MIN_OPTIONS_SIZE);
287 r = dhcp_option_append(opt, optlen,
288 DHCP_OPTION_MAXIMUM_MESSAGE_SIZE,
297 static int dhcp_client_send_raw(sd_dhcp_client *client, DHCPPacket *packet,
299 dhcp_packet_append_ip_headers(packet, INADDR_ANY, DHCP_PORT_CLIENT,
300 INADDR_BROADCAST, DHCP_PORT_SERVER, len);
302 return dhcp_network_send_raw_socket(client->fd, &client->link,
306 static int client_send_discover(sd_dhcp_client *client) {
307 _cleanup_free_ DHCPPacket *discover = NULL;
315 r = sd_event_now(client->event, CLOCK_MONOTONIC, &time_now);
318 assert(time_now >= client->start_time);
320 /* seconds between sending first and last DISCOVER
321 * must always be strictly positive to deal with broken servers */
322 client->secs = ((time_now - client->start_time) / USEC_PER_SEC) ? : 1;
324 optlen = DHCP_MIN_OPTIONS_SIZE;
325 len = sizeof(DHCPPacket) + optlen;
327 discover = malloc0(len);
331 r = client_message_init(client, &discover->dhcp, DHCP_DISCOVER,
336 if (client->last_addr != INADDR_ANY) {
337 r = dhcp_option_append(&opt, &optlen,
338 DHCP_OPTION_REQUESTED_IP_ADDRESS,
339 4, &client->last_addr);
344 r = dhcp_option_append(&opt, &optlen, DHCP_OPTION_END, 0, NULL);
348 r = dhcp_client_send_raw(client, discover, len - optlen);
352 log_dhcp_client(client, "DISCOVER");
357 static int client_send_request(sd_dhcp_client *client) {
358 _cleanup_free_ DHCPPacket *request;
363 optlen = DHCP_MIN_OPTIONS_SIZE;
364 len = sizeof(DHCPPacket) + optlen;
366 request = malloc0(len);
370 r = client_message_init(client, &request->dhcp, DHCP_REQUEST, &opt,
375 switch (client->state) {
377 case DHCP_STATE_INIT_REBOOT:
378 r = dhcp_option_append(&opt, &optlen,
379 DHCP_OPTION_REQUESTED_IP_ADDRESS,
380 4, &client->last_addr);
385 case DHCP_STATE_REQUESTING:
386 r = dhcp_option_append(&opt, &optlen,
387 DHCP_OPTION_REQUESTED_IP_ADDRESS,
388 4, &client->lease->address);
392 r = dhcp_option_append(&opt, &optlen,
393 DHCP_OPTION_SERVER_IDENTIFIER,
394 4, &client->lease->server_address);
399 case DHCP_STATE_INIT:
400 case DHCP_STATE_SELECTING:
401 case DHCP_STATE_REBOOTING:
402 case DHCP_STATE_BOUND:
403 case DHCP_STATE_RENEWING:
404 case DHCP_STATE_REBINDING:
409 r = dhcp_option_append(&opt, &optlen, DHCP_OPTION_END, 0, NULL);
413 if (client->state == DHCP_STATE_RENEWING) {
414 r = dhcp_network_send_udp_socket(client->fd,
415 client->lease->server_address,
418 len - optlen - DHCP_IP_UDP_SIZE);
420 r = dhcp_client_send_raw(client, request, len - optlen);
425 log_dhcp_client(client, "REQUEST");
430 static int client_timeout_resend(sd_event_source *s, uint64_t usec,
432 sd_dhcp_client *client = userdata;
433 usec_t next_timeout = 0;
440 assert(client->event);
442 r = sd_event_now(client->event, CLOCK_MONOTONIC, &time_now);
446 switch (client->state) {
447 case DHCP_STATE_RENEWING:
449 time_left = (client->lease->t2 - client->lease->t1) / 2;
453 next_timeout = time_now + time_left * USEC_PER_SEC;
457 case DHCP_STATE_REBINDING:
459 time_left = (client->lease->lifetime - client->lease->t2) / 2;
463 next_timeout = time_now + time_left * USEC_PER_SEC;
466 case DHCP_STATE_REBOOTING:
467 /* start over as we did not receive a timely ack or nak */
468 client->state = DHCP_STATE_INIT;
470 client->xid = random_u32();
473 case DHCP_STATE_INIT:
474 case DHCP_STATE_INIT_REBOOT:
475 case DHCP_STATE_SELECTING:
476 case DHCP_STATE_REQUESTING:
477 case DHCP_STATE_BOUND:
479 if (client->attempt < 64)
480 client->attempt *= 2;
482 next_timeout = time_now + (client->attempt - 1) * USEC_PER_SEC;
487 next_timeout += (random_u32() & 0x1fffff);
489 client->timeout_resend = sd_event_source_unref(client->timeout_resend);
491 r = sd_event_add_time(client->event,
492 &client->timeout_resend,
494 next_timeout, 10 * USEC_PER_MSEC,
495 client_timeout_resend, client);
499 r = sd_event_source_set_priority(client->timeout_resend,
500 client->event_priority);
504 switch (client->state) {
505 case DHCP_STATE_INIT:
506 r = client_send_discover(client);
508 client->state = DHCP_STATE_SELECTING;
511 if (client->attempt >= 64)
517 case DHCP_STATE_SELECTING:
518 r = client_send_discover(client);
519 if (r < 0 && client->attempt >= 64)
524 case DHCP_STATE_INIT_REBOOT:
525 case DHCP_STATE_REQUESTING:
526 case DHCP_STATE_RENEWING:
527 case DHCP_STATE_REBINDING:
528 r = client_send_request(client);
529 if (r < 0 && client->attempt >= 64)
532 if (client->state == DHCP_STATE_INIT_REBOOT)
533 client->state = DHCP_STATE_REBOOTING;
535 client->request_sent = time_now;
539 case DHCP_STATE_REBOOTING:
540 case DHCP_STATE_BOUND:
548 client_stop(client, r);
550 /* Errors were dealt with when stopping the client, don't spill
551 errors into the event loop handler */
555 static int client_initialize_events(sd_dhcp_client *client,
556 sd_event_io_handler_t io_callback) {
560 assert(client->event);
562 r = sd_event_add_io(client->event, &client->receive_message,
563 client->fd, EPOLLIN, io_callback,
568 r = sd_event_source_set_priority(client->receive_message,
569 client->event_priority);
573 client->timeout_resend = sd_event_source_unref(client->timeout_resend);
575 r = sd_event_add_time(client->event,
576 &client->timeout_resend,
579 client_timeout_resend, client);
583 r = sd_event_source_set_priority(client->timeout_resend,
584 client->event_priority);
588 client_stop(client, r);
594 static int client_start(sd_dhcp_client *client) {
597 assert_return(client, -EINVAL);
598 assert_return(client->event, -EINVAL);
599 assert_return(client->index > 0, -EINVAL);
600 assert_return(client->fd < 0, -EBUSY);
601 assert_return(client->xid == 0, -EINVAL);
602 assert_return(client->state == DHCP_STATE_INIT ||
603 client->state == DHCP_STATE_INIT_REBOOT, -EBUSY);
605 client->xid = random_u32();
607 r = dhcp_network_bind_raw_socket(client->index, &client->link, client->xid);
610 client_stop(client, r);
615 if (client->state == DHCP_STATE_INIT) {
616 client->start_time = now(CLOCK_MONOTONIC);
620 log_dhcp_client(client, "STARTED");
622 return client_initialize_events(client, client_receive_message_raw);
625 static int client_timeout_expire(sd_event_source *s, uint64_t usec,
627 sd_dhcp_client *client = userdata;
629 log_dhcp_client(client, "EXPIRED");
631 client = client_notify(client, DHCP_EVENT_EXPIRED);
633 /* lease was lost, start over if not freed */
635 client_initialize(client);
636 client_start(client);
642 static int client_timeout_t2(sd_event_source *s, uint64_t usec, void *userdata) {
643 sd_dhcp_client *client = userdata;
646 client->receive_message = sd_event_source_unref(client->receive_message);
647 client->fd = safe_close(client->fd);
649 client->state = DHCP_STATE_REBINDING;
652 r = dhcp_network_bind_raw_socket(client->index, &client->link, client->xid);
654 client_stop(client, r);
660 log_dhcp_client(client, "TIMEOUT T2");
662 return client_initialize_events(client, client_receive_message_raw);
665 static int client_timeout_t1(sd_event_source *s, uint64_t usec,
667 sd_dhcp_client *client = userdata;
670 client->state = DHCP_STATE_RENEWING;
673 r = dhcp_network_bind_udp_socket(client->index,
674 client->lease->address,
677 client_stop(client, r);
683 log_dhcp_client(client, "TIMEOUT T1");
685 return client_initialize_events(client, client_receive_message_udp);
688 static int client_handle_offer(sd_dhcp_client *client, DHCPMessage *offer,
690 _cleanup_dhcp_lease_unref_ sd_dhcp_lease *lease = NULL;
693 r = dhcp_lease_new(&lease);
697 r = dhcp_option_parse(offer, len, dhcp_lease_parse_options, lease);
698 if (r != DHCP_OFFER) {
699 log_dhcp_client(client, "receieved message was not an OFFER, ignoring");
703 lease->next_server = offer->siaddr;
705 lease->address = offer->yiaddr;
707 if (lease->address == INADDR_ANY ||
708 lease->server_address == INADDR_ANY ||
709 lease->lifetime == 0) {
710 log_dhcp_client(client, "receieved lease lacks address, server "
711 "address or lease lifetime, ignoring");
715 if (lease->subnet_mask == INADDR_ANY) {
716 r = dhcp_lease_set_default_subnet_mask(lease);
718 log_dhcp_client(client, "receieved lease lacks subnet "
719 "mask, and a fallback one can not be "
720 "generated, ignoring");
725 client->lease = lease;
728 log_dhcp_client(client, "OFFER");
733 static int client_handle_ack(sd_dhcp_client *client, DHCPMessage *ack,
735 _cleanup_dhcp_lease_unref_ sd_dhcp_lease *lease = NULL;
738 r = dhcp_lease_new(&lease);
742 r = dhcp_option_parse(ack, len, dhcp_lease_parse_options, lease);
744 log_dhcp_client(client, "NAK");
745 return DHCP_EVENT_NO_LEASE;
749 log_dhcp_client(client, "receieved message was not an ACK, ignoring");
753 lease->next_server = ack->siaddr;
755 lease->address = ack->yiaddr;
757 if (lease->address == INADDR_ANY ||
758 lease->server_address == INADDR_ANY ||
759 lease->lifetime == 0) {
760 log_dhcp_client(client, "receieved lease lacks address, server "
761 "address or lease lifetime, ignoring");
765 if (lease->subnet_mask == INADDR_ANY) {
766 r = dhcp_lease_set_default_subnet_mask(lease);
768 log_dhcp_client(client, "receieved lease lacks subnet "
769 "mask, and a fallback one can not be "
770 "generated, ignoring");
775 r = DHCP_EVENT_IP_ACQUIRE;
777 if (client->lease->address != lease->address ||
778 client->lease->subnet_mask != lease->subnet_mask ||
779 client->lease->router != lease->router) {
780 r = DHCP_EVENT_IP_CHANGE;
783 client->lease = sd_dhcp_lease_unref(client->lease);
786 client->lease = lease;
789 log_dhcp_client(client, "ACK");
794 static uint64_t client_compute_timeout(sd_dhcp_client *client,
795 uint32_t lifetime, double factor) {
797 assert(client->request_sent);
800 return client->request_sent + ((lifetime - 3) * USEC_PER_SEC * factor) +
801 + (random_u32() & 0x1fffff);
804 static int client_set_lease_timeouts(sd_dhcp_client *client) {
806 uint64_t lifetime_timeout;
809 char time_string[FORMAT_TIMESPAN_MAX];
813 assert(client->event);
814 assert(client->lease);
815 assert(client->lease->lifetime);
817 client->timeout_t1 = sd_event_source_unref(client->timeout_t1);
818 client->timeout_t2 = sd_event_source_unref(client->timeout_t2);
819 client->timeout_expire = sd_event_source_unref(client->timeout_expire);
821 /* don't set timers for infinite leases */
822 if (client->lease->lifetime == 0xffffffff)
825 r = sd_event_now(client->event, CLOCK_MONOTONIC, &time_now);
828 assert(client->request_sent <= time_now);
830 /* convert the various timeouts from relative (secs) to absolute (usecs) */
831 lifetime_timeout = client_compute_timeout(client, client->lease->lifetime, 1);
832 if (client->lease->t1 && client->lease->t2) {
833 /* both T1 and T2 are given */
834 if (client->lease->t1 < client->lease->t2 &&
835 client->lease->t2 < client->lease->lifetime) {
836 /* they are both valid */
837 t2_timeout = client_compute_timeout(client, client->lease->t2, 1);
838 t1_timeout = client_compute_timeout(client, client->lease->t1, 1);
841 t2_timeout = client_compute_timeout(client, client->lease->lifetime, 7.0 / 8.0);
842 client->lease->t2 = (client->lease->lifetime * 7) / 8;
843 t1_timeout = client_compute_timeout(client, client->lease->lifetime, 0.5);
844 client->lease->t1 = client->lease->lifetime / 2;
846 } else if (client->lease->t2 && client->lease->t2 < client->lease->lifetime) {
847 /* only T2 is given, and it is valid */
848 t2_timeout = client_compute_timeout(client, client->lease->t2, 1);
849 t1_timeout = client_compute_timeout(client, client->lease->lifetime, 0.5);
850 client->lease->t1 = client->lease->lifetime / 2;
851 if (t2_timeout <= t1_timeout) {
852 /* the computed T1 would be invalid, so discard T2 */
853 t2_timeout = client_compute_timeout(client, client->lease->lifetime, 7.0 / 8.0);
854 client->lease->t2 = (client->lease->lifetime * 7) / 8;
856 } else if (client->lease->t1 && client->lease->t1 < client->lease->lifetime) {
857 /* only T1 is given, and it is valid */
858 t1_timeout = client_compute_timeout(client, client->lease->t1, 1);
859 t2_timeout = client_compute_timeout(client, client->lease->lifetime, 7.0 / 8.0);
860 client->lease->t2 = (client->lease->lifetime * 7) / 8;
861 if (t2_timeout <= t1_timeout) {
862 /* the computed T2 would be invalid, so discard T1 */
863 t2_timeout = client_compute_timeout(client, client->lease->lifetime, 0.5);
864 client->lease->t2 = client->lease->lifetime / 2;
867 /* fall back to the default timeouts */
868 t1_timeout = client_compute_timeout(client, client->lease->lifetime, 0.5);
869 client->lease->t1 = client->lease->lifetime / 2;
870 t2_timeout = client_compute_timeout(client, client->lease->lifetime, 7.0 / 8.0);
871 client->lease->t2 = (client->lease->lifetime * 7) / 8;
874 /* arm lifetime timeout */
875 r = sd_event_add_time(client->event, &client->timeout_expire,
877 lifetime_timeout, 10 * USEC_PER_MSEC,
878 client_timeout_expire, client);
882 r = sd_event_source_set_priority(client->timeout_expire,
883 client->event_priority);
887 log_dhcp_client(client, "lease expires in %s",
888 format_timespan(time_string, FORMAT_TIMESPAN_MAX,
889 lifetime_timeout - time_now, 0));
891 /* don't arm earlier timeouts if this has already expired */
892 if (lifetime_timeout <= time_now)
896 r = sd_event_add_time(client->event,
901 client_timeout_t2, client);
905 r = sd_event_source_set_priority(client->timeout_t2,
906 client->event_priority);
910 log_dhcp_client(client, "T2 expires in %s",
911 format_timespan(time_string, FORMAT_TIMESPAN_MAX,
912 t2_timeout - time_now, 0));
914 /* don't arm earlier timeout if this has already expired */
915 if (t2_timeout <= time_now)
919 r = sd_event_add_time(client->event,
922 t1_timeout, 10 * USEC_PER_MSEC,
923 client_timeout_t1, client);
927 r = sd_event_source_set_priority(client->timeout_t1,
928 client->event_priority);
932 log_dhcp_client(client, "T1 expires in %s",
933 format_timespan(time_string, FORMAT_TIMESPAN_MAX,
934 t1_timeout - time_now, 0));
939 static int client_handle_message(sd_dhcp_client *client, DHCPMessage *message,
941 int r = 0, notify_event = 0;
944 assert(client->event);
947 if (be32toh(message->magic) != DHCP_MAGIC_COOKIE) {
948 log_dhcp_client(client, "not a DHCP message: ignoring");
952 if (message->op != BOOTREPLY) {
953 log_dhcp_client(client, "not a BOOTREPLY message: ignoring");
957 if (be32toh(message->xid) != client->xid) {
958 log_dhcp_client(client, "received xid (%u) does not match "
959 "expected (%u): ignoring",
960 be32toh(message->xid), client->xid);
964 if (message->htype != ARPHRD_ETHER || message->hlen != ETHER_ADDR_LEN) {
965 log_dhcp_client(client, "not an ethernet packet");
969 if (memcmp(&message->chaddr[0], &client->client_id.mac_addr,
971 log_dhcp_client(client, "received chaddr does not match "
972 "expected: ignoring");
976 switch (client->state) {
977 case DHCP_STATE_SELECTING:
979 r = client_handle_offer(client, message, len);
982 client->timeout_resend =
983 sd_event_source_unref(client->timeout_resend);
985 client->state = DHCP_STATE_REQUESTING;
988 r = sd_event_add_time(client->event,
989 &client->timeout_resend,
992 client_timeout_resend, client);
996 r = sd_event_source_set_priority(client->timeout_resend,
997 client->event_priority);
1000 } else if (r == -ENOMSG)
1001 /* invalid message, let's ignore it */
1006 case DHCP_STATE_REBOOTING:
1007 case DHCP_STATE_REQUESTING:
1008 case DHCP_STATE_RENEWING:
1009 case DHCP_STATE_REBINDING:
1011 r = client_handle_ack(client, message, len);
1012 if (r == DHCP_EVENT_NO_LEASE) {
1014 client->timeout_resend =
1015 sd_event_source_unref(client->timeout_resend);
1017 if (client->state == DHCP_STATE_REBOOTING) {
1018 r = client_initialize(client);
1022 r = client_start(client);
1028 } else if (r >= 0) {
1029 client->timeout_resend =
1030 sd_event_source_unref(client->timeout_resend);
1032 if (IN_SET(client->state, DHCP_STATE_REQUESTING,
1033 DHCP_STATE_REBOOTING))
1034 notify_event = DHCP_EVENT_IP_ACQUIRE;
1035 else if (r != DHCP_EVENT_IP_ACQUIRE)
1038 client->state = DHCP_STATE_BOUND;
1039 client->attempt = 1;
1041 client->last_addr = client->lease->address;
1043 r = client_set_lease_timeouts(client);
1048 client = client_notify(client, notify_event);
1053 client->receive_message =
1054 sd_event_source_unref(client->receive_message);
1055 client->fd = safe_close(client->fd);
1056 } else if (r == -ENOMSG)
1057 /* invalid message, let's ignore it */
1062 case DHCP_STATE_INIT:
1063 case DHCP_STATE_INIT_REBOOT:
1064 case DHCP_STATE_BOUND:
1070 if (r < 0 || r == DHCP_EVENT_NO_LEASE)
1071 client_stop(client, r);
1076 static int client_receive_message_udp(sd_event_source *s, int fd,
1077 uint32_t revents, void *userdata) {
1078 sd_dhcp_client *client = userdata;
1079 _cleanup_free_ DHCPMessage *message = NULL;
1080 int buflen = 0, len, r;
1085 r = ioctl(fd, FIONREAD, &buflen);
1086 if (r < 0 || buflen <= 0)
1087 buflen = sizeof(DHCPMessage) + DHCP_MIN_OPTIONS_SIZE;
1089 message = malloc0(buflen);
1093 len = read(fd, message, buflen);
1095 log_dhcp_client(client, "could not receive message from UDP "
1096 "socket: %s", strerror(errno));
1098 } else if ((size_t)len < sizeof(DHCPMessage))
1101 return client_handle_message(client, message, len);
1104 static int client_receive_message_raw(sd_event_source *s, int fd,
1105 uint32_t revents, void *userdata) {
1106 sd_dhcp_client *client = userdata;
1107 _cleanup_free_ DHCPPacket *packet = NULL;
1108 uint8_t cmsgbuf[CMSG_LEN(sizeof(struct tpacket_auxdata))];
1109 struct iovec iov = {};
1110 struct msghdr msg = {
1113 .msg_control = cmsgbuf,
1114 .msg_controllen = sizeof(cmsgbuf),
1116 struct cmsghdr *cmsg;
1117 bool checksum = true;
1118 int buflen = 0, len, r;
1123 r = ioctl(fd, FIONREAD, &buflen);
1124 if (r < 0 || buflen <= 0)
1125 buflen = sizeof(DHCPPacket) + DHCP_MIN_OPTIONS_SIZE;
1127 packet = malloc0(buflen);
1131 iov.iov_base = packet;
1132 iov.iov_len = buflen;
1134 len = recvmsg(fd, &msg, 0);
1136 log_dhcp_client(client, "could not receive message from raw "
1137 "socket: %s", strerror(errno));
1139 } else if ((size_t)len < sizeof(DHCPPacket))
1142 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
1143 if (cmsg->cmsg_level == SOL_PACKET &&
1144 cmsg->cmsg_type == PACKET_AUXDATA &&
1145 cmsg->cmsg_len == CMSG_LEN(sizeof(struct tpacket_auxdata))) {
1146 struct tpacket_auxdata *aux = (struct tpacket_auxdata*)CMSG_DATA(cmsg);
1148 checksum = !(aux->tp_status & TP_STATUS_CSUMNOTREADY);
1153 r = dhcp_packet_verify_headers(packet, len, checksum);
1157 len -= DHCP_IP_UDP_SIZE;
1159 return client_handle_message(client, &packet->dhcp, len);
1162 int sd_dhcp_client_start(sd_dhcp_client *client) {
1165 assert_return(client, -EINVAL);
1167 r = client_initialize(client);
1171 if (client->last_addr)
1172 client->state = DHCP_STATE_INIT_REBOOT;
1174 return client_start(client);
1177 int sd_dhcp_client_stop(sd_dhcp_client *client) {
1178 assert_return(client, -EINVAL);
1180 client_stop(client, DHCP_EVENT_STOP);
1185 int sd_dhcp_client_attach_event(sd_dhcp_client *client, sd_event *event,
1189 assert_return(client, -EINVAL);
1190 assert_return(!client->event, -EBUSY);
1193 client->event = sd_event_ref(event);
1195 r = sd_event_default(&client->event);
1200 client->event_priority = priority;
1205 int sd_dhcp_client_detach_event(sd_dhcp_client *client) {
1206 assert_return(client, -EINVAL);
1208 client->event = sd_event_unref(client->event);
1213 sd_event *sd_dhcp_client_get_event(sd_dhcp_client *client) {
1217 return client->event;
1220 sd_dhcp_client *sd_dhcp_client_ref(sd_dhcp_client *client) {
1222 assert_se(REFCNT_INC(client->n_ref) >= 2);
1227 sd_dhcp_client *sd_dhcp_client_unref(sd_dhcp_client *client) {
1228 if (client && REFCNT_DEC(client->n_ref) <= 0) {
1229 log_dhcp_client(client, "UNREF");
1231 client_initialize(client);
1233 client->receive_message =
1234 sd_event_source_unref(client->receive_message);
1236 sd_dhcp_client_detach_event(client);
1238 free(client->req_opts);
1247 DEFINE_TRIVIAL_CLEANUP_FUNC(sd_dhcp_client*, sd_dhcp_client_unref);
1248 #define _cleanup_dhcp_client_free_ _cleanup_(sd_dhcp_client_unrefp)
1250 int sd_dhcp_client_new(sd_dhcp_client **ret) {
1251 _cleanup_dhcp_client_free_ sd_dhcp_client *client = NULL;
1253 assert_return(ret, -EINVAL);
1255 client = new0(sd_dhcp_client, 1);
1259 client->n_ref = REFCNT_INIT;
1260 client->state = DHCP_STATE_INIT;
1263 client->attempt = 1;
1265 client->req_opts_size = ELEMENTSOF(default_req_opts);
1267 client->req_opts = memdup(default_req_opts, client->req_opts_size);
1268 if (!client->req_opts)