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/>.
21 #include <net/ethernet.h>
22 #include <net/if_arp.h>
26 #include <sys/ioctl.h>
27 #include <linux/if_infiniband.h>
29 #include "sd-dhcp-client.h"
31 #include "alloc-util.h"
33 #include "dhcp-identifier.h"
34 #include "dhcp-internal.h"
35 #include "dhcp-lease-internal.h"
36 #include "dhcp-protocol.h"
37 #include "random-util.h"
38 #include "string-util.h"
41 #define MAX_CLIENT_ID_LEN (sizeof(uint32_t) + MAX_DUID_LEN) /* Arbitrary limit */
42 #define MAX_MAC_ADDR_LEN CONST_MAX(INFINIBAND_ALEN, ETH_ALEN)
44 struct sd_dhcp_client
{
50 sd_event_source
*timeout_resend
;
53 union sockaddr_union link
;
54 sd_event_source
*receive_message
;
55 bool request_broadcast
;
57 size_t req_opts_allocated
;
60 uint8_t mac_addr
[MAX_MAC_ADDR_LEN
];
67 /* 0: Generic (non-LL) (RFC 2132) */
68 uint8_t data
[MAX_CLIENT_ID_LEN
];
71 /* 1: Ethernet Link-Layer (RFC 2132) */
72 uint8_t haddr
[ETH_ALEN
];
75 /* 2 - 254: ARP/Link-Layer (RFC 2132) */
79 /* 255: Node-specific (RFC 4361) */
84 uint8_t data
[MAX_CLIENT_ID_LEN
];
90 char *vendor_class_identifier
;
96 sd_event_source
*timeout_t1
;
97 sd_event_source
*timeout_t2
;
98 sd_event_source
*timeout_expire
;
99 sd_dhcp_client_cb_t cb
;
101 sd_dhcp_lease
*lease
;
104 static const uint8_t default_req_opts
[] = {
105 DHCP_OPTION_SUBNET_MASK
,
107 DHCP_OPTION_HOST_NAME
,
108 DHCP_OPTION_DOMAIN_NAME
,
109 DHCP_OPTION_DOMAIN_NAME_SERVER
,
112 static int client_receive_message_raw(sd_event_source
*s
, int fd
,
113 uint32_t revents
, void *userdata
);
114 static int client_receive_message_udp(sd_event_source
*s
, int fd
,
115 uint32_t revents
, void *userdata
);
116 static void client_stop(sd_dhcp_client
*client
, int error
);
118 int sd_dhcp_client_set_callback(sd_dhcp_client
*client
, sd_dhcp_client_cb_t cb
,
120 assert_return(client
, -EINVAL
);
123 client
->userdata
= userdata
;
128 int sd_dhcp_client_set_request_broadcast(sd_dhcp_client
*client
, int broadcast
) {
129 assert_return(client
, -EINVAL
);
131 client
->request_broadcast
= !!broadcast
;
136 int sd_dhcp_client_set_request_option(sd_dhcp_client
*client
, uint8_t option
) {
139 assert_return(client
, -EINVAL
);
140 assert_return (IN_SET(client
->state
, DHCP_STATE_INIT
,
141 DHCP_STATE_STOPPED
), -EBUSY
);
144 case DHCP_OPTION_PAD
:
145 case DHCP_OPTION_OVERLOAD
:
146 case DHCP_OPTION_MESSAGE_TYPE
:
147 case DHCP_OPTION_PARAMETER_REQUEST_LIST
:
148 case DHCP_OPTION_END
:
155 for (i
= 0; i
< client
->req_opts_size
; i
++)
156 if (client
->req_opts
[i
] == option
)
159 if (!GREEDY_REALLOC(client
->req_opts
, client
->req_opts_allocated
,
160 client
->req_opts_size
+ 1))
163 client
->req_opts
[client
->req_opts_size
++] = option
;
168 int sd_dhcp_client_set_request_address(sd_dhcp_client
*client
,
169 const struct in_addr
*last_addr
) {
170 assert_return(client
, -EINVAL
);
171 assert_return (IN_SET(client
->state
, DHCP_STATE_INIT
,
172 DHCP_STATE_STOPPED
), -EBUSY
);
175 client
->last_addr
= last_addr
->s_addr
;
177 client
->last_addr
= INADDR_ANY
;
182 int sd_dhcp_client_set_index(sd_dhcp_client
*client
, int interface_index
) {
183 assert_return(client
, -EINVAL
);
184 assert_return (IN_SET(client
->state
, DHCP_STATE_INIT
,
185 DHCP_STATE_STOPPED
), -EBUSY
);
186 assert_return(interface_index
> 0, -EINVAL
);
188 client
->index
= interface_index
;
193 int sd_dhcp_client_set_mac(sd_dhcp_client
*client
, const uint8_t *addr
,
194 size_t addr_len
, uint16_t arp_type
) {
195 DHCP_CLIENT_DONT_DESTROY(client
);
196 bool need_restart
= false;
198 assert_return(client
, -EINVAL
);
199 assert_return(addr
, -EINVAL
);
200 assert_return(addr_len
> 0 && addr_len
<= MAX_MAC_ADDR_LEN
, -EINVAL
);
201 assert_return(arp_type
> 0, -EINVAL
);
203 if (arp_type
== ARPHRD_ETHER
)
204 assert_return(addr_len
== ETH_ALEN
, -EINVAL
);
205 else if (arp_type
== ARPHRD_INFINIBAND
)
206 assert_return(addr_len
== INFINIBAND_ALEN
, -EINVAL
);
210 if (client
->mac_addr_len
== addr_len
&&
211 memcmp(&client
->mac_addr
, addr
, addr_len
) == 0)
214 if (!IN_SET(client
->state
, DHCP_STATE_INIT
, DHCP_STATE_STOPPED
)) {
215 log_dhcp_client(client
, "Changing MAC address on running DHCP "
216 "client, restarting");
218 client_stop(client
, SD_DHCP_CLIENT_EVENT_STOP
);
221 memcpy(&client
->mac_addr
, addr
, addr_len
);
222 client
->mac_addr_len
= addr_len
;
223 client
->arp_type
= arp_type
;
225 if (need_restart
&& client
->state
!= DHCP_STATE_STOPPED
)
226 sd_dhcp_client_start(client
);
231 int sd_dhcp_client_get_client_id(sd_dhcp_client
*client
, uint8_t *type
,
232 const uint8_t **data
, size_t *data_len
) {
234 assert_return(client
, -EINVAL
);
235 assert_return(type
, -EINVAL
);
236 assert_return(data
, -EINVAL
);
237 assert_return(data_len
, -EINVAL
);
242 if (client
->client_id_len
) {
243 *type
= client
->client_id
.type
;
244 *data
= client
->client_id
.raw
.data
;
245 *data_len
= client
->client_id_len
- sizeof(client
->client_id
.type
);
251 int sd_dhcp_client_set_client_id(sd_dhcp_client
*client
, uint8_t type
,
252 const uint8_t *data
, size_t data_len
) {
253 DHCP_CLIENT_DONT_DESTROY(client
);
254 bool need_restart
= false;
256 assert_return(client
, -EINVAL
);
257 assert_return(data
, -EINVAL
);
258 assert_return(data_len
> 0 && data_len
<= MAX_CLIENT_ID_LEN
, -EINVAL
);
262 if (data_len
!= ETH_ALEN
)
265 case ARPHRD_INFINIBAND
:
266 if (data_len
!= INFINIBAND_ALEN
)
273 if (client
->client_id_len
== data_len
+ sizeof(client
->client_id
.type
) &&
274 client
->client_id
.type
== type
&&
275 memcmp(&client
->client_id
.raw
.data
, data
, data_len
) == 0)
278 if (!IN_SET(client
->state
, DHCP_STATE_INIT
, DHCP_STATE_STOPPED
)) {
279 log_dhcp_client(client
, "Changing client ID on running DHCP "
280 "client, restarting");
282 client_stop(client
, SD_DHCP_CLIENT_EVENT_STOP
);
285 client
->client_id
.type
= type
;
286 memcpy(&client
->client_id
.raw
.data
, data
, data_len
);
287 client
->client_id_len
= data_len
+ sizeof (client
->client_id
.type
);
289 if (need_restart
&& client
->state
!= DHCP_STATE_STOPPED
)
290 sd_dhcp_client_start(client
);
295 int sd_dhcp_client_set_hostname(sd_dhcp_client
*client
,
296 const char *hostname
) {
297 char *new_hostname
= NULL
;
299 assert_return(client
, -EINVAL
);
301 if (streq_ptr(client
->hostname
, hostname
))
305 new_hostname
= strdup(hostname
);
310 free(client
->hostname
);
311 client
->hostname
= new_hostname
;
316 int sd_dhcp_client_set_vendor_class_identifier(sd_dhcp_client
*client
,
318 char *new_vci
= NULL
;
320 assert_return(client
, -EINVAL
);
322 new_vci
= strdup(vci
);
326 free(client
->vendor_class_identifier
);
328 client
->vendor_class_identifier
= new_vci
;
333 int sd_dhcp_client_set_mtu(sd_dhcp_client
*client
, uint32_t mtu
) {
334 assert_return(client
, -EINVAL
);
335 assert_return(mtu
>= DHCP_DEFAULT_MIN_SIZE
, -ERANGE
);
342 int sd_dhcp_client_get_lease(sd_dhcp_client
*client
, sd_dhcp_lease
**ret
) {
343 assert_return(client
, -EINVAL
);
344 assert_return(ret
, -EINVAL
);
346 if (client
->state
!= DHCP_STATE_BOUND
&&
347 client
->state
!= DHCP_STATE_RENEWING
&&
348 client
->state
!= DHCP_STATE_REBINDING
)
349 return -EADDRNOTAVAIL
;
351 *ret
= client
->lease
;
356 static void client_notify(sd_dhcp_client
*client
, int event
) {
358 client
->cb(client
, event
, client
->userdata
);
361 static int client_initialize(sd_dhcp_client
*client
) {
362 assert_return(client
, -EINVAL
);
364 client
->receive_message
=
365 sd_event_source_unref(client
->receive_message
);
367 client
->fd
= asynchronous_close(client
->fd
);
369 client
->timeout_resend
= sd_event_source_unref(client
->timeout_resend
);
371 client
->timeout_t1
= sd_event_source_unref(client
->timeout_t1
);
372 client
->timeout_t2
= sd_event_source_unref(client
->timeout_t2
);
373 client
->timeout_expire
= sd_event_source_unref(client
->timeout_expire
);
377 client
->state
= DHCP_STATE_INIT
;
380 client
->lease
= sd_dhcp_lease_unref(client
->lease
);
385 static void client_stop(sd_dhcp_client
*client
, int error
) {
389 log_dhcp_client(client
, "STOPPED: %s", strerror(-error
));
390 else if (error
== SD_DHCP_CLIENT_EVENT_STOP
)
391 log_dhcp_client(client
, "STOPPED");
393 log_dhcp_client(client
, "STOPPED: Unknown event");
395 client_notify(client
, error
);
397 client_initialize(client
);
400 static int client_message_init(sd_dhcp_client
*client
, DHCPPacket
**ret
,
401 uint8_t type
, size_t *_optlen
, size_t *_optoffset
) {
402 _cleanup_free_ DHCPPacket
*packet
;
403 size_t optlen
, optoffset
, size
;
410 assert(client
->start_time
);
414 assert(type
== DHCP_DISCOVER
|| type
== DHCP_REQUEST
);
416 optlen
= DHCP_MIN_OPTIONS_SIZE
;
417 size
= sizeof(DHCPPacket
) + optlen
;
419 packet
= malloc0(size
);
423 r
= dhcp_message_init(&packet
->dhcp
, BOOTREQUEST
, client
->xid
, type
,
424 client
->arp_type
, optlen
, &optoffset
);
428 /* Although 'secs' field is a SHOULD in RFC 2131, certain DHCP servers
429 refuse to issue an DHCP lease if 'secs' is set to zero */
430 r
= sd_event_now(client
->event
, clock_boottime_or_monotonic(), &time_now
);
433 assert(time_now
>= client
->start_time
);
435 /* seconds between sending first and last DISCOVER
436 * must always be strictly positive to deal with broken servers */
437 secs
= ((time_now
- client
->start_time
) / USEC_PER_SEC
) ? : 1;
438 packet
->dhcp
.secs
= htobe16(secs
);
440 /* RFC2132 section 4.1
441 A client that cannot receive unicast IP datagrams until its protocol
442 software has been configured with an IP address SHOULD set the
443 BROADCAST bit in the 'flags' field to 1 in any DHCPDISCOVER or
444 DHCPREQUEST messages that client sends. The BROADCAST bit will
445 provide a hint to the DHCP server and BOOTP relay agent to broadcast
446 any messages to the client on the client's subnet.
448 Note: some interfaces needs this to be enabled, but some networks
449 needs this to be disabled as broadcasts are filteretd, so this
450 needs to be configurable */
451 if (client
->request_broadcast
|| client
->arp_type
!= ARPHRD_ETHER
)
452 packet
->dhcp
.flags
= htobe16(0x8000);
454 /* RFC2132 section 4.1.1:
455 The client MUST include its hardware address in the ’chaddr’ field, if
456 necessary for delivery of DHCP reply messages. Non-Ethernet
457 interfaces will leave 'chaddr' empty and use the client identifier
458 instead (eg, RFC 4390 section 2.1).
460 if (client
->arp_type
== ARPHRD_ETHER
)
461 memcpy(&packet
->dhcp
.chaddr
, &client
->mac_addr
, ETH_ALEN
);
463 /* If no client identifier exists, construct an RFC 4361-compliant one */
464 if (client
->client_id_len
== 0) {
467 client
->client_id
.type
= 255;
469 r
= dhcp_identifier_set_iaid(client
->index
, client
->mac_addr
, client
->mac_addr_len
, &client
->client_id
.ns
.iaid
);
473 r
= dhcp_identifier_set_duid_en(&client
->client_id
.ns
.duid
, &duid_len
);
477 client
->client_id_len
= sizeof(client
->client_id
.type
) + sizeof(client
->client_id
.ns
.iaid
) + duid_len
;
480 /* Some DHCP servers will refuse to issue an DHCP lease if the Client
481 Identifier option is not set */
482 if (client
->client_id_len
) {
483 r
= dhcp_option_append(&packet
->dhcp
, optlen
, &optoffset
, 0,
484 DHCP_OPTION_CLIENT_IDENTIFIER
,
485 client
->client_id_len
,
491 /* RFC2131 section 3.5:
492 in its initial DHCPDISCOVER or DHCPREQUEST message, a
493 client may provide the server with a list of specific
494 parameters the client is interested in. If the client
495 includes a list of parameters in a DHCPDISCOVER message,
496 it MUST include that list in any subsequent DHCPREQUEST
499 r
= dhcp_option_append(&packet
->dhcp
, optlen
, &optoffset
, 0,
500 DHCP_OPTION_PARAMETER_REQUEST_LIST
,
501 client
->req_opts_size
, client
->req_opts
);
505 /* RFC2131 section 3.5:
506 The client SHOULD include the ’maximum DHCP message size’ option to
507 let the server know how large the server may make its DHCP messages.
509 Note (from ConnMan): Some DHCP servers will send bigger DHCP packets
510 than the defined default size unless the Maximum Messge Size option
513 RFC3442 "Requirements to Avoid Sizing Constraints":
514 Because a full routing table can be quite large, the standard 576
515 octet maximum size for a DHCP message may be too short to contain
516 some legitimate Classless Static Route options. Because of this,
517 clients implementing the Classless Static Route option SHOULD send a
518 Maximum DHCP Message Size [4] option if the DHCP client's TCP/IP
519 stack is capable of receiving larger IP datagrams. In this case, the
520 client SHOULD set the value of this option to at least the MTU of the
521 interface that the client is configuring. The client MAY set the
522 value of this option higher, up to the size of the largest UDP packet
523 it is prepared to accept. (Note that the value specified in the
524 Maximum DHCP Message Size option is the total maximum packet size,
525 including IP and UDP headers.)
527 max_size
= htobe16(size
);
528 r
= dhcp_option_append(&packet
->dhcp
, client
->mtu
, &optoffset
, 0,
529 DHCP_OPTION_MAXIMUM_MESSAGE_SIZE
,
535 *_optoffset
= optoffset
;
542 static int dhcp_client_send_raw(sd_dhcp_client
*client
, DHCPPacket
*packet
,
544 dhcp_packet_append_ip_headers(packet
, INADDR_ANY
, DHCP_PORT_CLIENT
,
545 INADDR_BROADCAST
, DHCP_PORT_SERVER
, len
);
547 return dhcp_network_send_raw_socket(client
->fd
, &client
->link
,
551 static int client_send_discover(sd_dhcp_client
*client
) {
552 _cleanup_free_ DHCPPacket
*discover
= NULL
;
553 size_t optoffset
, optlen
;
557 assert(client
->state
== DHCP_STATE_INIT
||
558 client
->state
== DHCP_STATE_SELECTING
);
560 r
= client_message_init(client
, &discover
, DHCP_DISCOVER
,
561 &optlen
, &optoffset
);
565 /* the client may suggest values for the network address
566 and lease time in the DHCPDISCOVER message. The client may include
567 the ’requested IP address’ option to suggest that a particular IP
568 address be assigned, and may include the ’IP address lease time’
569 option to suggest the lease time it would like.
571 if (client
->last_addr
!= INADDR_ANY
) {
572 r
= dhcp_option_append(&discover
->dhcp
, optlen
, &optoffset
, 0,
573 DHCP_OPTION_REQUESTED_IP_ADDRESS
,
574 4, &client
->last_addr
);
579 /* it is unclear from RFC 2131 if client should send hostname in
580 DHCPDISCOVER but dhclient does and so we do as well
582 if (client
->hostname
) {
583 r
= dhcp_option_append(&discover
->dhcp
, optlen
, &optoffset
, 0,
584 DHCP_OPTION_HOST_NAME
,
585 strlen(client
->hostname
), client
->hostname
);
590 if (client
->vendor_class_identifier
) {
591 r
= dhcp_option_append(&discover
->dhcp
, optlen
, &optoffset
, 0,
592 DHCP_OPTION_VENDOR_CLASS_IDENTIFIER
,
593 strlen(client
->vendor_class_identifier
),
594 client
->vendor_class_identifier
);
599 r
= dhcp_option_append(&discover
->dhcp
, optlen
, &optoffset
, 0,
600 DHCP_OPTION_END
, 0, NULL
);
604 /* We currently ignore:
605 The client SHOULD wait a random time between one and ten seconds to
606 desynchronize the use of DHCP at startup.
608 r
= dhcp_client_send_raw(client
, discover
, sizeof(DHCPPacket
) + optoffset
);
612 log_dhcp_client(client
, "DISCOVER");
617 static int client_send_request(sd_dhcp_client
*client
) {
618 _cleanup_free_ DHCPPacket
*request
= NULL
;
619 size_t optoffset
, optlen
;
622 r
= client_message_init(client
, &request
, DHCP_REQUEST
,
623 &optlen
, &optoffset
);
627 switch (client
->state
) {
628 /* See RFC2131 section 4.3.2 (note that there is a typo in the RFC,
629 SELECTING should be REQUESTING)
632 case DHCP_STATE_REQUESTING
:
633 /* Client inserts the address of the selected server in ’server
634 identifier’, ’ciaddr’ MUST be zero, ’requested IP address’ MUST be
635 filled in with the yiaddr value from the chosen DHCPOFFER.
638 r
= dhcp_option_append(&request
->dhcp
, optlen
, &optoffset
, 0,
639 DHCP_OPTION_SERVER_IDENTIFIER
,
640 4, &client
->lease
->server_address
);
644 r
= dhcp_option_append(&request
->dhcp
, optlen
, &optoffset
, 0,
645 DHCP_OPTION_REQUESTED_IP_ADDRESS
,
646 4, &client
->lease
->address
);
652 case DHCP_STATE_INIT_REBOOT
:
653 /* ’server identifier’ MUST NOT be filled in, ’requested IP address’
654 option MUST be filled in with client’s notion of its previously
655 assigned address. ’ciaddr’ MUST be zero.
657 r
= dhcp_option_append(&request
->dhcp
, optlen
, &optoffset
, 0,
658 DHCP_OPTION_REQUESTED_IP_ADDRESS
,
659 4, &client
->last_addr
);
664 case DHCP_STATE_RENEWING
:
665 /* ’server identifier’ MUST NOT be filled in, ’requested IP address’
666 option MUST NOT be filled in, ’ciaddr’ MUST be filled in with
667 client’s IP address.
671 case DHCP_STATE_REBINDING
:
672 /* ’server identifier’ MUST NOT be filled in, ’requested IP address’
673 option MUST NOT be filled in, ’ciaddr’ MUST be filled in with
674 client’s IP address.
676 This message MUST be broadcast to the 0xffffffff IP broadcast address.
678 request
->dhcp
.ciaddr
= client
->lease
->address
;
682 case DHCP_STATE_INIT
:
683 case DHCP_STATE_SELECTING
:
684 case DHCP_STATE_REBOOTING
:
685 case DHCP_STATE_BOUND
:
686 case DHCP_STATE_STOPPED
:
690 if (client
->hostname
) {
691 r
= dhcp_option_append(&request
->dhcp
, optlen
, &optoffset
, 0,
692 DHCP_OPTION_HOST_NAME
,
693 strlen(client
->hostname
), client
->hostname
);
698 r
= dhcp_option_append(&request
->dhcp
, optlen
, &optoffset
, 0,
699 DHCP_OPTION_END
, 0, NULL
);
703 if (client
->state
== DHCP_STATE_RENEWING
) {
704 r
= dhcp_network_send_udp_socket(client
->fd
,
705 client
->lease
->server_address
,
708 sizeof(DHCPMessage
) + optoffset
);
710 r
= dhcp_client_send_raw(client
, request
, sizeof(DHCPPacket
) + optoffset
);
715 switch (client
->state
) {
716 case DHCP_STATE_REQUESTING
:
717 log_dhcp_client(client
, "REQUEST (requesting)");
719 case DHCP_STATE_INIT_REBOOT
:
720 log_dhcp_client(client
, "REQUEST (init-reboot)");
722 case DHCP_STATE_RENEWING
:
723 log_dhcp_client(client
, "REQUEST (renewing)");
725 case DHCP_STATE_REBINDING
:
726 log_dhcp_client(client
, "REQUEST (rebinding)");
729 log_dhcp_client(client
, "REQUEST (invalid)");
736 static int client_start(sd_dhcp_client
*client
);
738 static int client_timeout_resend(sd_event_source
*s
, uint64_t usec
,
740 sd_dhcp_client
*client
= userdata
;
741 DHCP_CLIENT_DONT_DESTROY(client
);
742 usec_t next_timeout
= 0;
749 assert(client
->event
);
751 r
= sd_event_now(client
->event
, clock_boottime_or_monotonic(), &time_now
);
755 switch (client
->state
) {
756 case DHCP_STATE_RENEWING
:
758 time_left
= (client
->lease
->t2
- client
->lease
->t1
) / 2;
762 next_timeout
= time_now
+ time_left
* USEC_PER_SEC
;
766 case DHCP_STATE_REBINDING
:
768 time_left
= (client
->lease
->lifetime
- client
->lease
->t2
) / 2;
772 next_timeout
= time_now
+ time_left
* USEC_PER_SEC
;
775 case DHCP_STATE_REBOOTING
:
776 /* start over as we did not receive a timely ack or nak */
777 r
= client_initialize(client
);
781 r
= client_start(client
);
785 log_dhcp_client(client
, "REBOOTED");
789 case DHCP_STATE_INIT
:
790 case DHCP_STATE_INIT_REBOOT
:
791 case DHCP_STATE_SELECTING
:
792 case DHCP_STATE_REQUESTING
:
793 case DHCP_STATE_BOUND
:
795 if (client
->attempt
< 64)
796 client
->attempt
*= 2;
798 next_timeout
= time_now
+ (client
->attempt
- 1) * USEC_PER_SEC
;
802 case DHCP_STATE_STOPPED
:
807 next_timeout
+= (random_u32() & 0x1fffff);
809 client
->timeout_resend
= sd_event_source_unref(client
->timeout_resend
);
811 r
= sd_event_add_time(client
->event
,
812 &client
->timeout_resend
,
813 clock_boottime_or_monotonic(),
814 next_timeout
, 10 * USEC_PER_MSEC
,
815 client_timeout_resend
, client
);
819 r
= sd_event_source_set_priority(client
->timeout_resend
,
820 client
->event_priority
);
824 r
= sd_event_source_set_description(client
->timeout_resend
, "dhcp4-resend-timer");
828 switch (client
->state
) {
829 case DHCP_STATE_INIT
:
830 r
= client_send_discover(client
);
832 client
->state
= DHCP_STATE_SELECTING
;
835 if (client
->attempt
>= 64)
841 case DHCP_STATE_SELECTING
:
842 r
= client_send_discover(client
);
843 if (r
< 0 && client
->attempt
>= 64)
848 case DHCP_STATE_INIT_REBOOT
:
849 case DHCP_STATE_REQUESTING
:
850 case DHCP_STATE_RENEWING
:
851 case DHCP_STATE_REBINDING
:
852 r
= client_send_request(client
);
853 if (r
< 0 && client
->attempt
>= 64)
856 if (client
->state
== DHCP_STATE_INIT_REBOOT
)
857 client
->state
= DHCP_STATE_REBOOTING
;
859 client
->request_sent
= time_now
;
863 case DHCP_STATE_REBOOTING
:
864 case DHCP_STATE_BOUND
:
868 case DHCP_STATE_STOPPED
:
876 client_stop(client
, r
);
878 /* Errors were dealt with when stopping the client, don't spill
879 errors into the event loop handler */
883 static int client_initialize_io_events(sd_dhcp_client
*client
,
884 sd_event_io_handler_t io_callback
) {
888 assert(client
->event
);
890 r
= sd_event_add_io(client
->event
, &client
->receive_message
,
891 client
->fd
, EPOLLIN
, io_callback
,
896 r
= sd_event_source_set_priority(client
->receive_message
,
897 client
->event_priority
);
901 r
= sd_event_source_set_description(client
->receive_message
, "dhcp4-receive-message");
907 client_stop(client
, r
);
912 static int client_initialize_time_events(sd_dhcp_client
*client
) {
916 assert(client
->event
);
918 client
->timeout_resend
= sd_event_source_unref(client
->timeout_resend
);
920 r
= sd_event_add_time(client
->event
,
921 &client
->timeout_resend
,
922 clock_boottime_or_monotonic(),
924 client_timeout_resend
, client
);
928 r
= sd_event_source_set_priority(client
->timeout_resend
,
929 client
->event_priority
);
933 r
= sd_event_source_set_description(client
->timeout_resend
, "dhcp4-resend-timer");
939 client_stop(client
, r
);
945 static int client_initialize_events(sd_dhcp_client
*client
,
946 sd_event_io_handler_t io_callback
) {
947 client_initialize_io_events(client
, io_callback
);
948 client_initialize_time_events(client
);
953 static int client_start(sd_dhcp_client
*client
) {
956 assert_return(client
, -EINVAL
);
957 assert_return(client
->event
, -EINVAL
);
958 assert_return(client
->index
> 0, -EINVAL
);
959 assert_return(client
->fd
< 0, -EBUSY
);
960 assert_return(client
->xid
== 0, -EINVAL
);
961 assert_return(client
->state
== DHCP_STATE_INIT
||
962 client
->state
== DHCP_STATE_INIT_REBOOT
, -EBUSY
);
964 client
->xid
= random_u32();
966 r
= dhcp_network_bind_raw_socket(client
->index
, &client
->link
,
967 client
->xid
, client
->mac_addr
,
968 client
->mac_addr_len
, client
->arp_type
);
970 client_stop(client
, r
);
975 if (client
->state
== DHCP_STATE_INIT
|| client
->state
== DHCP_STATE_INIT_REBOOT
)
976 client
->start_time
= now(clock_boottime_or_monotonic());
978 return client_initialize_events(client
, client_receive_message_raw
);
981 static int client_timeout_expire(sd_event_source
*s
, uint64_t usec
,
983 sd_dhcp_client
*client
= userdata
;
984 DHCP_CLIENT_DONT_DESTROY(client
);
986 log_dhcp_client(client
, "EXPIRED");
988 client_notify(client
, SD_DHCP_CLIENT_EVENT_EXPIRED
);
990 /* lease was lost, start over if not freed or stopped in callback */
991 if (client
->state
!= DHCP_STATE_STOPPED
) {
992 client_initialize(client
);
993 client_start(client
);
999 static int client_timeout_t2(sd_event_source
*s
, uint64_t usec
, void *userdata
) {
1000 sd_dhcp_client
*client
= userdata
;
1001 DHCP_CLIENT_DONT_DESTROY(client
);
1004 client
->receive_message
= sd_event_source_unref(client
->receive_message
);
1005 client
->fd
= asynchronous_close(client
->fd
);
1007 client
->state
= DHCP_STATE_REBINDING
;
1008 client
->attempt
= 1;
1010 r
= dhcp_network_bind_raw_socket(client
->index
, &client
->link
,
1011 client
->xid
, client
->mac_addr
,
1012 client
->mac_addr_len
, client
->arp_type
);
1014 client_stop(client
, r
);
1019 return client_initialize_events(client
, client_receive_message_raw
);
1022 static int client_timeout_t1(sd_event_source
*s
, uint64_t usec
,
1024 sd_dhcp_client
*client
= userdata
;
1025 DHCP_CLIENT_DONT_DESTROY(client
);
1027 client
->state
= DHCP_STATE_RENEWING
;
1028 client
->attempt
= 1;
1030 return client_initialize_time_events(client
);
1033 static int client_handle_offer(sd_dhcp_client
*client
, DHCPMessage
*offer
,
1035 _cleanup_dhcp_lease_unref_ sd_dhcp_lease
*lease
= NULL
;
1038 r
= dhcp_lease_new(&lease
);
1042 if (client
->client_id_len
) {
1043 r
= dhcp_lease_set_client_id(lease
,
1044 (uint8_t *) &client
->client_id
,
1045 client
->client_id_len
);
1050 r
= dhcp_option_parse(offer
, len
, dhcp_lease_parse_options
, lease
);
1051 if (r
!= DHCP_OFFER
) {
1052 log_dhcp_client(client
, "received message was not an OFFER, ignoring");
1056 lease
->next_server
= offer
->siaddr
;
1057 lease
->address
= offer
->yiaddr
;
1059 if (lease
->address
== 0 ||
1060 lease
->server_address
== 0 ||
1061 lease
->lifetime
== 0) {
1062 log_dhcp_client(client
, "received lease lacks address, server address or lease lifetime, ignoring");
1066 if (!lease
->have_subnet_mask
) {
1067 r
= dhcp_lease_set_default_subnet_mask(lease
);
1069 log_dhcp_client(client
, "received lease lacks subnet "
1070 "mask, and a fallback one can not be "
1071 "generated, ignoring");
1076 sd_dhcp_lease_unref(client
->lease
);
1077 client
->lease
= lease
;
1080 log_dhcp_client(client
, "OFFER");
1085 static int client_handle_forcerenew(sd_dhcp_client
*client
, DHCPMessage
*force
,
1089 r
= dhcp_option_parse(force
, len
, NULL
, NULL
);
1090 if (r
!= DHCP_FORCERENEW
)
1093 log_dhcp_client(client
, "FORCERENEW");
1098 static int client_handle_ack(sd_dhcp_client
*client
, DHCPMessage
*ack
,
1100 _cleanup_dhcp_lease_unref_ sd_dhcp_lease
*lease
= NULL
;
1103 r
= dhcp_lease_new(&lease
);
1107 if (client
->client_id_len
) {
1108 r
= dhcp_lease_set_client_id(lease
,
1109 (uint8_t *) &client
->client_id
,
1110 client
->client_id_len
);
1115 r
= dhcp_option_parse(ack
, len
, dhcp_lease_parse_options
, lease
);
1116 if (r
== DHCP_NAK
) {
1117 log_dhcp_client(client
, "NAK");
1118 return -EADDRNOTAVAIL
;
1121 if (r
!= DHCP_ACK
) {
1122 log_dhcp_client(client
, "received message was not an ACK, ignoring");
1126 lease
->next_server
= ack
->siaddr
;
1128 lease
->address
= ack
->yiaddr
;
1130 if (lease
->address
== INADDR_ANY
||
1131 lease
->server_address
== INADDR_ANY
||
1132 lease
->lifetime
== 0) {
1133 log_dhcp_client(client
, "received lease lacks address, server "
1134 "address or lease lifetime, ignoring");
1138 if (lease
->subnet_mask
== INADDR_ANY
) {
1139 r
= dhcp_lease_set_default_subnet_mask(lease
);
1141 log_dhcp_client(client
, "received lease lacks subnet "
1142 "mask, and a fallback one can not be "
1143 "generated, ignoring");
1148 r
= SD_DHCP_CLIENT_EVENT_IP_ACQUIRE
;
1149 if (client
->lease
) {
1150 if (client
->lease
->address
!= lease
->address
||
1151 client
->lease
->subnet_mask
!= lease
->subnet_mask
||
1152 client
->lease
->router
!= lease
->router
) {
1153 r
= SD_DHCP_CLIENT_EVENT_IP_CHANGE
;
1155 r
= SD_DHCP_CLIENT_EVENT_RENEW
;
1157 client
->lease
= sd_dhcp_lease_unref(client
->lease
);
1160 client
->lease
= lease
;
1163 log_dhcp_client(client
, "ACK");
1168 static uint64_t client_compute_timeout(sd_dhcp_client
*client
, uint32_t lifetime
, double factor
) {
1170 assert(client
->request_sent
);
1171 assert(lifetime
> 0);
1178 return client
->request_sent
+ (lifetime
* USEC_PER_SEC
* factor
) +
1179 + (random_u32() & 0x1fffff);
1182 static int client_set_lease_timeouts(sd_dhcp_client
*client
) {
1184 uint64_t lifetime_timeout
;
1185 uint64_t t2_timeout
;
1186 uint64_t t1_timeout
;
1187 char time_string
[FORMAT_TIMESPAN_MAX
];
1191 assert(client
->event
);
1192 assert(client
->lease
);
1193 assert(client
->lease
->lifetime
);
1195 client
->timeout_t1
= sd_event_source_unref(client
->timeout_t1
);
1196 client
->timeout_t2
= sd_event_source_unref(client
->timeout_t2
);
1197 client
->timeout_expire
= sd_event_source_unref(client
->timeout_expire
);
1199 /* don't set timers for infinite leases */
1200 if (client
->lease
->lifetime
== 0xffffffff)
1203 r
= sd_event_now(client
->event
, clock_boottime_or_monotonic(), &time_now
);
1206 assert(client
->request_sent
<= time_now
);
1208 /* convert the various timeouts from relative (secs) to absolute (usecs) */
1209 lifetime_timeout
= client_compute_timeout(client
, client
->lease
->lifetime
, 1);
1210 if (client
->lease
->t1
> 0 && client
->lease
->t2
> 0) {
1211 /* both T1 and T2 are given */
1212 if (client
->lease
->t1
< client
->lease
->t2
&&
1213 client
->lease
->t2
< client
->lease
->lifetime
) {
1214 /* they are both valid */
1215 t2_timeout
= client_compute_timeout(client
, client
->lease
->t2
, 1);
1216 t1_timeout
= client_compute_timeout(client
, client
->lease
->t1
, 1);
1219 t2_timeout
= client_compute_timeout(client
, client
->lease
->lifetime
, 7.0 / 8.0);
1220 client
->lease
->t2
= (client
->lease
->lifetime
* 7) / 8;
1221 t1_timeout
= client_compute_timeout(client
, client
->lease
->lifetime
, 0.5);
1222 client
->lease
->t1
= client
->lease
->lifetime
/ 2;
1224 } else if (client
->lease
->t2
> 0 && client
->lease
->t2
< client
->lease
->lifetime
) {
1225 /* only T2 is given, and it is valid */
1226 t2_timeout
= client_compute_timeout(client
, client
->lease
->t2
, 1);
1227 t1_timeout
= client_compute_timeout(client
, client
->lease
->lifetime
, 0.5);
1228 client
->lease
->t1
= client
->lease
->lifetime
/ 2;
1229 if (t2_timeout
<= t1_timeout
) {
1230 /* the computed T1 would be invalid, so discard T2 */
1231 t2_timeout
= client_compute_timeout(client
, client
->lease
->lifetime
, 7.0 / 8.0);
1232 client
->lease
->t2
= (client
->lease
->lifetime
* 7) / 8;
1234 } else if (client
->lease
->t1
> 0 && client
->lease
->t1
< client
->lease
->lifetime
) {
1235 /* only T1 is given, and it is valid */
1236 t1_timeout
= client_compute_timeout(client
, client
->lease
->t1
, 1);
1237 t2_timeout
= client_compute_timeout(client
, client
->lease
->lifetime
, 7.0 / 8.0);
1238 client
->lease
->t2
= (client
->lease
->lifetime
* 7) / 8;
1239 if (t2_timeout
<= t1_timeout
) {
1240 /* the computed T2 would be invalid, so discard T1 */
1241 t2_timeout
= client_compute_timeout(client
, client
->lease
->lifetime
, 0.5);
1242 client
->lease
->t2
= client
->lease
->lifetime
/ 2;
1245 /* fall back to the default timeouts */
1246 t1_timeout
= client_compute_timeout(client
, client
->lease
->lifetime
, 0.5);
1247 client
->lease
->t1
= client
->lease
->lifetime
/ 2;
1248 t2_timeout
= client_compute_timeout(client
, client
->lease
->lifetime
, 7.0 / 8.0);
1249 client
->lease
->t2
= (client
->lease
->lifetime
* 7) / 8;
1252 /* arm lifetime timeout */
1253 r
= sd_event_add_time(client
->event
, &client
->timeout_expire
,
1254 clock_boottime_or_monotonic(),
1255 lifetime_timeout
, 10 * USEC_PER_MSEC
,
1256 client_timeout_expire
, client
);
1260 r
= sd_event_source_set_priority(client
->timeout_expire
,
1261 client
->event_priority
);
1265 r
= sd_event_source_set_description(client
->timeout_expire
, "dhcp4-lifetime");
1269 log_dhcp_client(client
, "lease expires in %s",
1270 format_timespan(time_string
, FORMAT_TIMESPAN_MAX
, lifetime_timeout
- time_now
, USEC_PER_SEC
));
1272 /* don't arm earlier timeouts if this has already expired */
1273 if (lifetime_timeout
<= time_now
)
1276 /* arm T2 timeout */
1277 r
= sd_event_add_time(client
->event
,
1278 &client
->timeout_t2
,
1279 clock_boottime_or_monotonic(),
1282 client_timeout_t2
, client
);
1286 r
= sd_event_source_set_priority(client
->timeout_t2
,
1287 client
->event_priority
);
1291 r
= sd_event_source_set_description(client
->timeout_t2
, "dhcp4-t2-timeout");
1295 log_dhcp_client(client
, "T2 expires in %s",
1296 format_timespan(time_string
, FORMAT_TIMESPAN_MAX
, t2_timeout
- time_now
, USEC_PER_SEC
));
1298 /* don't arm earlier timeout if this has already expired */
1299 if (t2_timeout
<= time_now
)
1302 /* arm T1 timeout */
1303 r
= sd_event_add_time(client
->event
,
1304 &client
->timeout_t1
,
1305 clock_boottime_or_monotonic(),
1306 t1_timeout
, 10 * USEC_PER_MSEC
,
1307 client_timeout_t1
, client
);
1311 r
= sd_event_source_set_priority(client
->timeout_t1
,
1312 client
->event_priority
);
1316 r
= sd_event_source_set_description(client
->timeout_t1
, "dhcp4-t1-timer");
1320 log_dhcp_client(client
, "T1 expires in %s",
1321 format_timespan(time_string
, FORMAT_TIMESPAN_MAX
, t1_timeout
- time_now
, USEC_PER_SEC
));
1326 static int client_handle_message(sd_dhcp_client
*client
, DHCPMessage
*message
,
1328 DHCP_CLIENT_DONT_DESTROY(client
);
1329 int r
= 0, notify_event
= 0;
1332 assert(client
->event
);
1335 switch (client
->state
) {
1336 case DHCP_STATE_SELECTING
:
1338 r
= client_handle_offer(client
, message
, len
);
1341 client
->timeout_resend
=
1342 sd_event_source_unref(client
->timeout_resend
);
1344 client
->state
= DHCP_STATE_REQUESTING
;
1345 client
->attempt
= 1;
1347 r
= sd_event_add_time(client
->event
,
1348 &client
->timeout_resend
,
1349 clock_boottime_or_monotonic(),
1351 client_timeout_resend
, client
);
1355 r
= sd_event_source_set_priority(client
->timeout_resend
,
1356 client
->event_priority
);
1360 r
= sd_event_source_set_description(client
->timeout_resend
, "dhcp4-resend-timer");
1363 } else if (r
== -ENOMSG
)
1364 /* invalid message, let's ignore it */
1369 case DHCP_STATE_REBOOTING
:
1370 case DHCP_STATE_REQUESTING
:
1371 case DHCP_STATE_RENEWING
:
1372 case DHCP_STATE_REBINDING
:
1374 r
= client_handle_ack(client
, message
, len
);
1376 client
->timeout_resend
=
1377 sd_event_source_unref(client
->timeout_resend
);
1378 client
->receive_message
=
1379 sd_event_source_unref(client
->receive_message
);
1380 client
->fd
= asynchronous_close(client
->fd
);
1382 if (IN_SET(client
->state
, DHCP_STATE_REQUESTING
,
1383 DHCP_STATE_REBOOTING
))
1384 notify_event
= SD_DHCP_CLIENT_EVENT_IP_ACQUIRE
;
1385 else if (r
!= SD_DHCP_CLIENT_EVENT_IP_ACQUIRE
)
1388 client
->state
= DHCP_STATE_BOUND
;
1389 client
->attempt
= 1;
1391 client
->last_addr
= client
->lease
->address
;
1393 r
= client_set_lease_timeouts(client
);
1395 log_dhcp_client(client
, "could not set lease timeouts");
1399 r
= dhcp_network_bind_udp_socket(client
->lease
->address
,
1402 log_dhcp_client(client
, "could not bind UDP socket");
1408 client_initialize_io_events(client
, client_receive_message_udp
);
1411 client_notify(client
, notify_event
);
1412 if (client
->state
== DHCP_STATE_STOPPED
)
1416 } else if (r
== -EADDRNOTAVAIL
) {
1417 /* got a NAK, let's restart the client */
1418 client
->timeout_resend
=
1419 sd_event_source_unref(client
->timeout_resend
);
1421 r
= client_initialize(client
);
1425 r
= client_start(client
);
1429 log_dhcp_client(client
, "REBOOTED");
1432 } else if (r
== -ENOMSG
)
1433 /* invalid message, let's ignore it */
1438 case DHCP_STATE_BOUND
:
1439 r
= client_handle_forcerenew(client
, message
, len
);
1441 r
= client_timeout_t1(NULL
, 0, client
);
1444 } else if (r
== -ENOMSG
)
1445 /* invalid message, let's ignore it */
1450 case DHCP_STATE_INIT
:
1451 case DHCP_STATE_INIT_REBOOT
:
1455 case DHCP_STATE_STOPPED
:
1462 client_stop(client
, r
);
1467 static int client_receive_message_udp(sd_event_source
*s
, int fd
,
1468 uint32_t revents
, void *userdata
) {
1469 sd_dhcp_client
*client
= userdata
;
1470 _cleanup_free_ DHCPMessage
*message
= NULL
;
1471 int buflen
= 0, len
, r
;
1472 const struct ether_addr zero_mac
= { { 0, 0, 0, 0, 0, 0 } };
1473 const struct ether_addr
*expected_chaddr
= NULL
;
1474 uint8_t expected_hlen
= 0;
1479 r
= ioctl(fd
, FIONREAD
, &buflen
);
1484 /* this can't be right */
1487 message
= malloc0(buflen
);
1491 len
= read(fd
, message
, buflen
);
1493 log_dhcp_client(client
, "could not receive message from UDP "
1496 } else if ((size_t)len
< sizeof(DHCPMessage
)) {
1497 log_dhcp_client(client
, "too small to be a DHCP message: ignoring");
1501 if (be32toh(message
->magic
) != DHCP_MAGIC_COOKIE
) {
1502 log_dhcp_client(client
, "not a DHCP message: ignoring");
1506 if (message
->op
!= BOOTREPLY
) {
1507 log_dhcp_client(client
, "not a BOOTREPLY message: ignoring");
1511 if (message
->htype
!= client
->arp_type
) {
1512 log_dhcp_client(client
, "packet type does not match client type");
1516 if (client
->arp_type
== ARPHRD_ETHER
) {
1517 expected_hlen
= ETH_ALEN
;
1518 expected_chaddr
= (const struct ether_addr
*) &client
->mac_addr
;
1520 /* Non-Ethernet links expect zero chaddr */
1522 expected_chaddr
= &zero_mac
;
1525 if (message
->hlen
!= expected_hlen
) {
1526 log_dhcp_client(client
, "unexpected packet hlen %d", message
->hlen
);
1530 if (memcmp(&message
->chaddr
[0], expected_chaddr
, ETH_ALEN
)) {
1531 log_dhcp_client(client
, "received chaddr does not match "
1532 "expected: ignoring");
1536 if (client
->state
!= DHCP_STATE_BOUND
&&
1537 be32toh(message
->xid
) != client
->xid
) {
1538 /* in BOUND state, we may receive FORCERENEW with xid set by server,
1539 so ignore the xid in this case */
1540 log_dhcp_client(client
, "received xid (%u) does not match "
1541 "expected (%u): ignoring",
1542 be32toh(message
->xid
), client
->xid
);
1546 return client_handle_message(client
, message
, len
);
1549 static int client_receive_message_raw(sd_event_source
*s
, int fd
,
1550 uint32_t revents
, void *userdata
) {
1551 sd_dhcp_client
*client
= userdata
;
1552 _cleanup_free_ DHCPPacket
*packet
= NULL
;
1553 uint8_t cmsgbuf
[CMSG_LEN(sizeof(struct tpacket_auxdata
))];
1554 struct iovec iov
= {};
1555 struct msghdr msg
= {
1558 .msg_control
= cmsgbuf
,
1559 .msg_controllen
= sizeof(cmsgbuf
),
1561 struct cmsghdr
*cmsg
;
1562 bool checksum
= true;
1563 int buflen
= 0, len
, r
;
1568 r
= ioctl(fd
, FIONREAD
, &buflen
);
1573 /* this can't be right */
1576 packet
= malloc0(buflen
);
1580 iov
.iov_base
= packet
;
1581 iov
.iov_len
= buflen
;
1583 len
= recvmsg(fd
, &msg
, 0);
1585 log_dhcp_client(client
, "could not receive message from raw "
1588 } else if ((size_t)len
< sizeof(DHCPPacket
))
1591 CMSG_FOREACH(cmsg
, &msg
) {
1592 if (cmsg
->cmsg_level
== SOL_PACKET
&&
1593 cmsg
->cmsg_type
== PACKET_AUXDATA
&&
1594 cmsg
->cmsg_len
== CMSG_LEN(sizeof(struct tpacket_auxdata
))) {
1595 struct tpacket_auxdata
*aux
= (struct tpacket_auxdata
*)CMSG_DATA(cmsg
);
1597 checksum
= !(aux
->tp_status
& TP_STATUS_CSUMNOTREADY
);
1602 r
= dhcp_packet_verify_headers(packet
, len
, checksum
);
1606 len
-= DHCP_IP_UDP_SIZE
;
1608 return client_handle_message(client
, &packet
->dhcp
, len
);
1611 int sd_dhcp_client_start(sd_dhcp_client
*client
) {
1614 assert_return(client
, -EINVAL
);
1616 r
= client_initialize(client
);
1620 if (client
->last_addr
)
1621 client
->state
= DHCP_STATE_INIT_REBOOT
;
1623 r
= client_start(client
);
1625 log_dhcp_client(client
, "STARTED on ifindex %i", client
->index
);
1630 int sd_dhcp_client_stop(sd_dhcp_client
*client
) {
1631 DHCP_CLIENT_DONT_DESTROY(client
);
1633 assert_return(client
, -EINVAL
);
1635 client_stop(client
, SD_DHCP_CLIENT_EVENT_STOP
);
1636 client
->state
= DHCP_STATE_STOPPED
;
1641 int sd_dhcp_client_attach_event(sd_dhcp_client
*client
, sd_event
*event
,
1645 assert_return(client
, -EINVAL
);
1646 assert_return(!client
->event
, -EBUSY
);
1649 client
->event
= sd_event_ref(event
);
1651 r
= sd_event_default(&client
->event
);
1656 client
->event_priority
= priority
;
1661 int sd_dhcp_client_detach_event(sd_dhcp_client
*client
) {
1662 assert_return(client
, -EINVAL
);
1664 client
->event
= sd_event_unref(client
->event
);
1669 sd_event
*sd_dhcp_client_get_event(sd_dhcp_client
*client
) {
1673 return client
->event
;
1676 sd_dhcp_client
*sd_dhcp_client_ref(sd_dhcp_client
*client
) {
1681 assert(client
->n_ref
>= 1);
1687 sd_dhcp_client
*sd_dhcp_client_unref(sd_dhcp_client
*client
) {
1692 assert(client
->n_ref
>= 1);
1695 if (client
->n_ref
> 0)
1698 log_dhcp_client(client
, "FREE");
1700 client_initialize(client
);
1702 client
->receive_message
= sd_event_source_unref(client
->receive_message
);
1704 sd_dhcp_client_detach_event(client
);
1706 sd_dhcp_lease_unref(client
->lease
);
1708 free(client
->req_opts
);
1709 free(client
->hostname
);
1710 free(client
->vendor_class_identifier
);
1716 int sd_dhcp_client_new(sd_dhcp_client
**ret
) {
1717 _cleanup_dhcp_client_unref_ sd_dhcp_client
*client
= NULL
;
1719 assert_return(ret
, -EINVAL
);
1721 client
= new0(sd_dhcp_client
, 1);
1726 client
->state
= DHCP_STATE_INIT
;
1729 client
->attempt
= 1;
1730 client
->mtu
= DHCP_DEFAULT_MIN_SIZE
;
1732 client
->req_opts_size
= ELEMENTSOF(default_req_opts
);
1734 client
->req_opts
= memdup(default_req_opts
, client
->req_opts_size
);
1735 if (!client
->req_opts
)