1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2014 Tom Gundersen <teg@jklm.no>
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
23 #include <sys/ioctl.h>
25 #include <netinet/in.h>
27 #include "netlink-util.h"
28 #include "network-internal.h"
29 #include "socket-util.h"
32 #include "fileio-label.h"
33 #include "ordered-set.h"
34 #include "random-util.h"
35 #include "hostname-util.h"
37 #include "dns-domain.h"
38 #include "resolved-conf.h"
39 #include "resolved-bus.h"
40 #include "resolved-manager.h"
41 #include "resolved-llmnr.h"
43 #define SEND_TIMEOUT_USEC (200 * USEC_PER_MSEC)
45 static int manager_process_link(sd_netlink
*rtnl
, sd_netlink_message
*mm
, void *userdata
) {
46 Manager
*m
= userdata
;
55 r
= sd_netlink_message_get_type(mm
, &type
);
59 r
= sd_rtnl_message_link_get_ifindex(mm
, &ifindex
);
63 l
= hashmap_get(m
->links
, INT_TO_PTR(ifindex
));
71 r
= link_new(m
, &l
, ifindex
);
76 r
= link_update_rtnl(l
, mm
);
80 r
= link_update_monitor(l
);
85 log_debug("Found new link %i/%s", ifindex
, l
->name
);
92 log_debug("Removing link %i/%s", l
->ifindex
, l
->name
);
102 log_warning_errno(r
, "Failed to process RTNL link message: %m");
106 static int manager_process_address(sd_netlink
*rtnl
, sd_netlink_message
*mm
, void *userdata
) {
107 Manager
*m
= userdata
;
108 union in_addr_union address
;
110 int r
, ifindex
, family
;
118 r
= sd_netlink_message_get_type(mm
, &type
);
122 r
= sd_rtnl_message_addr_get_ifindex(mm
, &ifindex
);
126 l
= hashmap_get(m
->links
, INT_TO_PTR(ifindex
));
130 r
= sd_rtnl_message_addr_get_family(mm
, &family
);
137 r
= sd_netlink_message_read_in_addr(mm
, IFA_LOCAL
, &address
.in
);
139 r
= sd_netlink_message_read_in_addr(mm
, IFA_ADDRESS
, &address
.in
);
147 r
= sd_netlink_message_read_in6_addr(mm
, IFA_LOCAL
, &address
.in6
);
149 r
= sd_netlink_message_read_in6_addr(mm
, IFA_ADDRESS
, &address
.in6
);
160 a
= link_find_address(l
, family
, &address
);
167 r
= link_address_new(l
, &a
, family
, &address
);
172 r
= link_address_update_rtnl(a
, mm
);
180 link_address_free(a
);
187 log_warning_errno(r
, "Failed to process RTNL address message: %m");
191 static int manager_rtnl_listen(Manager
*m
) {
192 _cleanup_netlink_message_unref_ sd_netlink_message
*req
= NULL
, *reply
= NULL
;
193 sd_netlink_message
*i
;
198 /* First, subscribe to interfaces coming and going */
199 r
= sd_netlink_open(&m
->rtnl
);
203 r
= sd_netlink_attach_event(m
->rtnl
, m
->event
, 0);
207 r
= sd_netlink_add_match(m
->rtnl
, RTM_NEWLINK
, manager_process_link
, m
);
211 r
= sd_netlink_add_match(m
->rtnl
, RTM_DELLINK
, manager_process_link
, m
);
215 r
= sd_netlink_add_match(m
->rtnl
, RTM_NEWADDR
, manager_process_address
, m
);
219 r
= sd_netlink_add_match(m
->rtnl
, RTM_DELADDR
, manager_process_address
, m
);
223 /* Then, enumerate all links */
224 r
= sd_rtnl_message_new_link(m
->rtnl
, &req
, RTM_GETLINK
, 0);
228 r
= sd_netlink_message_request_dump(req
, true);
232 r
= sd_netlink_call(m
->rtnl
, req
, 0, &reply
);
236 for (i
= reply
; i
; i
= sd_netlink_message_next(i
)) {
237 r
= manager_process_link(m
->rtnl
, i
, m
);
242 req
= sd_netlink_message_unref(req
);
243 reply
= sd_netlink_message_unref(reply
);
245 /* Finally, enumerate all addresses, too */
246 r
= sd_rtnl_message_new_addr(m
->rtnl
, &req
, RTM_GETADDR
, 0, AF_UNSPEC
);
250 r
= sd_netlink_message_request_dump(req
, true);
254 r
= sd_netlink_call(m
->rtnl
, req
, 0, &reply
);
258 for (i
= reply
; i
; i
= sd_netlink_message_next(i
)) {
259 r
= manager_process_address(m
->rtnl
, i
, m
);
267 static int on_network_event(sd_event_source
*s
, int fd
, uint32_t revents
, void *userdata
) {
268 Manager
*m
= userdata
;
275 sd_network_monitor_flush(m
->network_monitor
);
277 HASHMAP_FOREACH(l
, m
->links
, i
) {
278 r
= link_update_monitor(l
);
280 log_warning_errno(r
, "Failed to update monitor information for %i: %m", l
->ifindex
);
283 r
= manager_write_resolv_conf(m
);
285 log_warning_errno(r
, "Could not update resolv.conf: %m");
290 static int manager_network_monitor_listen(Manager
*m
) {
295 r
= sd_network_monitor_new(&m
->network_monitor
, NULL
);
299 fd
= sd_network_monitor_get_fd(m
->network_monitor
);
303 events
= sd_network_monitor_get_events(m
->network_monitor
);
307 r
= sd_event_add_io(m
->event
, &m
->network_event_source
, fd
, events
, &on_network_event
, m
);
314 static int determine_hostname(char **ret
) {
315 _cleanup_free_
char *h
= NULL
, *n
= NULL
;
320 h
= gethostname_malloc();
324 if (!utf8_is_valid(h
)) {
325 log_error("System hostname is not UTF-8 clean.");
329 r
= dns_name_normalize(h
, &n
);
331 log_error("System hostname '%s' cannot be normalized.", h
);
341 static int on_hostname_change(sd_event_source
*es
, int fd
, uint32_t revents
, void *userdata
) {
342 _cleanup_free_
char *h
= NULL
;
343 Manager
*m
= userdata
;
348 r
= determine_hostname(&h
);
350 return 0; /* ignore invalid hostnames */
352 if (streq(h
, m
->hostname
))
355 log_info("System hostname changed to '%s'.", h
);
360 manager_refresh_rrs(m
);
365 static int manager_watch_hostname(Manager
*m
) {
370 m
->hostname_fd
= open("/proc/sys/kernel/hostname", O_RDONLY
|O_CLOEXEC
|O_NDELAY
|O_NOCTTY
);
371 if (m
->hostname_fd
< 0) {
372 log_warning_errno(errno
, "Failed to watch hostname: %m");
376 r
= sd_event_add_io(m
->event
, &m
->hostname_event_source
, m
->hostname_fd
, 0, on_hostname_change
, m
);
379 /* kernels prior to 3.2 don't support polling this file. Ignore the failure. */
380 m
->hostname_fd
= safe_close(m
->hostname_fd
);
382 return log_error_errno(r
, "Failed to add hostname event source: %m");
385 r
= determine_hostname(&m
->hostname
);
387 log_info("Defaulting to hostname 'linux'.");
388 m
->hostname
= strdup("linux");
392 log_info("Using system hostname '%s'.", m
->hostname
);
397 int manager_new(Manager
**ret
) {
398 _cleanup_(manager_freep
) Manager
*m
= NULL
;
403 m
= new0(Manager
, 1);
407 m
->llmnr_ipv4_udp_fd
= m
->llmnr_ipv6_udp_fd
= -1;
408 m
->llmnr_ipv4_tcp_fd
= m
->llmnr_ipv6_tcp_fd
= -1;
411 m
->llmnr_support
= SUPPORT_YES
;
412 m
->read_resolv_conf
= true;
414 r
= manager_parse_dns_server(m
, DNS_SERVER_FALLBACK
, DNS_SERVERS
);
418 r
= sd_event_default(&m
->event
);
422 sd_event_add_signal(m
->event
, NULL
, SIGTERM
, NULL
, NULL
);
423 sd_event_add_signal(m
->event
, NULL
, SIGINT
, NULL
, NULL
);
425 sd_event_set_watchdog(m
->event
, true);
427 r
= manager_watch_hostname(m
);
431 r
= dns_scope_new(m
, &m
->unicast_scope
, NULL
, DNS_PROTOCOL_DNS
, AF_UNSPEC
);
435 r
= manager_network_monitor_listen(m
);
439 r
= manager_rtnl_listen(m
);
443 r
= manager_connect_bus(m
);
453 int manager_start(Manager
*m
) {
458 r
= manager_llmnr_start(m
);
465 Manager
*manager_free(Manager
*m
) {
471 while ((l
= hashmap_first(m
->links
)))
474 while (m
->dns_queries
)
475 dns_query_free(m
->dns_queries
);
477 manager_flush_dns_servers(m
, DNS_SERVER_SYSTEM
);
478 manager_flush_dns_servers(m
, DNS_SERVER_FALLBACK
);
480 dns_scope_free(m
->unicast_scope
);
482 hashmap_free(m
->links
);
483 hashmap_free(m
->dns_transactions
);
485 sd_event_source_unref(m
->network_event_source
);
486 sd_network_monitor_unref(m
->network_monitor
);
488 manager_llmnr_stop(m
);
490 sd_bus_slot_unref(m
->prepare_for_sleep_slot
);
491 sd_event_source_unref(m
->bus_retry_event_source
);
492 sd_bus_unref(m
->bus
);
494 sd_event_unref(m
->event
);
496 dns_resource_key_unref(m
->host_ipv4_key
);
497 dns_resource_key_unref(m
->host_ipv6_key
);
499 safe_close(m
->hostname_fd
);
500 sd_event_source_unref(m
->hostname_event_source
);
508 int manager_read_resolv_conf(Manager
*m
) {
509 _cleanup_fclose_
FILE *f
= NULL
;
518 /* Reads the system /etc/resolv.conf, if it exists and is not
519 * symlinked to our own resolv.conf instance */
521 if (!m
->read_resolv_conf
)
524 r
= stat("/etc/resolv.conf", &st
);
527 log_warning_errno(errno
, "Failed to open /etc/resolv.conf: %m");
532 /* Have we already seen the file? */
533 t
= timespec_load(&st
.st_mtim
);
534 if (t
== m
->resolv_conf_mtime
)
537 m
->resolv_conf_mtime
= t
;
539 /* Is it symlinked to our own file? */
540 if (stat("/run/systemd/resolve/resolv.conf", &own
) >= 0 &&
541 st
.st_dev
== own
.st_dev
&&
542 st
.st_ino
== own
.st_ino
) {
547 f
= fopen("/etc/resolv.conf", "re");
550 log_warning_errno(errno
, "Failed to open /etc/resolv.conf: %m");
555 if (fstat(fileno(f
), &st
) < 0) {
556 log_error_errno(errno
, "Failed to stat open file: %m");
561 LIST_FOREACH(servers
, s
, m
->dns_servers
)
564 FOREACH_LINE(line
, f
, r
= -errno
; goto clear
) {
565 union in_addr_union address
;
573 if (*l
== '#' || *l
== ';')
576 a
= first_word(l
, "nameserver");
580 r
= in_addr_from_string_auto(a
, &family
, &address
);
582 log_warning("Failed to parse name server %s.", a
);
586 LIST_FOREACH(servers
, s
, m
->dns_servers
)
587 if (s
->family
== family
&& in_addr_equal(family
, &s
->address
, &address
) > 0)
593 r
= dns_server_new(m
, NULL
, DNS_SERVER_SYSTEM
, NULL
, family
, &address
);
599 LIST_FOREACH_SAFE(servers
, s
, nx
, m
->dns_servers
)
601 LIST_REMOVE(servers
, m
->dns_servers
, s
);
605 /* Whenever /etc/resolv.conf changes, start using the first
606 * DNS server of it. This is useful to deal with broken
607 * network managing implementations (like NetworkManager),
608 * that when connecting to a VPN place both the VPN DNS
609 * servers and the local ones in /etc/resolv.conf. Without
610 * resetting the DNS server to use back to the first entry we
611 * will continue to use the local one thus being unable to
612 * resolve VPN domains. */
613 manager_set_dns_server(m
, m
->dns_servers
);
618 while (m
->dns_servers
) {
621 LIST_REMOVE(servers
, m
->dns_servers
, s
);
628 static void write_resolv_conf_server(DnsServer
*s
, FILE *f
, unsigned *count
) {
629 _cleanup_free_
char *t
= NULL
;
636 r
= in_addr_to_string(s
->family
, &s
->address
, &t
);
638 log_warning_errno(r
, "Invalid DNS address. Ignoring: %m");
643 fputs("# Too many DNS servers configured, the following entries may be ignored.\n", f
);
645 fprintf(f
, "nameserver %s\n", t
);
649 static void write_resolv_conf_search(
650 const char *domain
, FILE *f
,
658 if (*count
>= MAXDNSRCH
||
659 *length
+ strlen(domain
) > 256) {
660 if (*count
== MAXDNSRCH
)
661 fputs(" # Too many search domains configured, remaining ones ignored.", f
);
663 fputs(" # Total length of all search domains is too long, remaining ones ignored.", f
);
668 fprintf(f
, " %s", domain
);
670 (*length
) += strlen(domain
);
674 static int write_resolv_conf_contents(FILE *f
, OrderedSet
*dns
, OrderedSet
*domains
) {
677 fputs("# This file is managed by systemd-resolved(8). Do not edit.\n#\n"
678 "# Third party programs must not access this file directly, but\n"
679 "# only through the symlink at /etc/resolv.conf. To manage\n"
680 "# resolv.conf(5) in a different way, replace the symlink by a\n"
681 "# static file or a different symlink.\n\n", f
);
683 if (ordered_set_isempty(dns
))
684 fputs("# No DNS servers known.\n", f
);
689 ORDERED_SET_FOREACH(s
, dns
, i
)
690 write_resolv_conf_server(s
, f
, &count
);
693 if (!ordered_set_isempty(domains
)) {
694 unsigned length
= 0, count
= 0;
698 ORDERED_SET_FOREACH(domain
, domains
, i
)
699 write_resolv_conf_search(domain
, f
, &count
, &length
);
703 return fflush_and_check(f
);
706 int manager_write_resolv_conf(Manager
*m
) {
707 static const char path
[] = "/run/systemd/resolve/resolv.conf";
708 _cleanup_free_
char *temp_path
= NULL
;
709 _cleanup_fclose_
FILE *f
= NULL
;
710 _cleanup_ordered_set_free_ OrderedSet
*dns
= NULL
, *domains
= NULL
;
718 /* Read the system /etc/resolv.conf first */
719 manager_read_resolv_conf(m
);
721 /* Add the full list to a set, to filter out duplicates */
722 dns
= ordered_set_new(&dns_server_hash_ops
);
726 domains
= ordered_set_new(&dns_name_hash_ops
);
730 /* First add the system-wide servers */
731 LIST_FOREACH(servers
, s
, m
->dns_servers
) {
732 r
= ordered_set_put(dns
, s
);
739 /* Then, add the per-link servers and domains */
740 HASHMAP_FOREACH(l
, m
->links
, i
) {
743 LIST_FOREACH(servers
, s
, l
->dns_servers
) {
744 r
= ordered_set_put(dns
, s
);
751 if (!l
->unicast_scope
)
754 STRV_FOREACH(domain
, l
->unicast_scope
->domains
) {
755 r
= ordered_set_put(domains
, *domain
);
763 /* If we found nothing, add the fallback servers */
764 if (ordered_set_isempty(dns
)) {
765 LIST_FOREACH(servers
, s
, m
->fallback_dns_servers
) {
766 r
= ordered_set_put(dns
, s
);
774 r
= fopen_temporary_label(path
, path
, &f
, &temp_path
);
778 fchmod(fileno(f
), 0644);
780 r
= write_resolv_conf_contents(f
, dns
, domains
);
784 if (rename(temp_path
, path
) < 0) {
793 (void) unlink(temp_path
);
797 int manager_recv(Manager
*m
, int fd
, DnsProtocol protocol
, DnsPacket
**ret
) {
798 _cleanup_(dns_packet_unrefp
) DnsPacket
*p
= NULL
;
800 struct cmsghdr header
; /* For alignment */
801 uint8_t buffer
[CMSG_SPACE(MAXSIZE(struct in_pktinfo
, struct in6_pktinfo
))
802 + CMSG_SPACE(int) /* ttl/hoplimit */
803 + EXTRA_CMSG_SPACE
/* kernel appears to require extra buffer space */];
805 union sockaddr_union sa
;
806 struct msghdr mh
= {};
807 struct cmsghdr
*cmsg
;
816 r
= ioctl(fd
, FIONREAD
, &ms
);
822 r
= dns_packet_new(&p
, protocol
, ms
);
826 iov
.iov_base
= DNS_PACKET_DATA(p
);
827 iov
.iov_len
= p
->allocated
;
829 mh
.msg_name
= &sa
.sa
;
830 mh
.msg_namelen
= sizeof(sa
);
833 mh
.msg_control
= &control
;
834 mh
.msg_controllen
= sizeof(control
);
836 l
= recvmsg(fd
, &mh
, 0);
838 if (errno
== EAGAIN
|| errno
== EINTR
)
847 assert(!(mh
.msg_flags
& MSG_CTRUNC
));
848 assert(!(mh
.msg_flags
& MSG_TRUNC
));
850 p
->size
= (size_t) l
;
852 p
->family
= sa
.sa
.sa_family
;
853 p
->ipproto
= IPPROTO_UDP
;
854 if (p
->family
== AF_INET
) {
855 p
->sender
.in
= sa
.in
.sin_addr
;
856 p
->sender_port
= be16toh(sa
.in
.sin_port
);
857 } else if (p
->family
== AF_INET6
) {
858 p
->sender
.in6
= sa
.in6
.sin6_addr
;
859 p
->sender_port
= be16toh(sa
.in6
.sin6_port
);
860 p
->ifindex
= sa
.in6
.sin6_scope_id
;
862 return -EAFNOSUPPORT
;
864 CMSG_FOREACH(cmsg
, &mh
) {
866 if (cmsg
->cmsg_level
== IPPROTO_IPV6
) {
867 assert(p
->family
== AF_INET6
);
869 switch (cmsg
->cmsg_type
) {
872 struct in6_pktinfo
*i
= (struct in6_pktinfo
*) CMSG_DATA(cmsg
);
875 p
->ifindex
= i
->ipi6_ifindex
;
877 p
->destination
.in6
= i
->ipi6_addr
;
882 p
->ttl
= *(int *) CMSG_DATA(cmsg
);
886 } else if (cmsg
->cmsg_level
== IPPROTO_IP
) {
887 assert(p
->family
== AF_INET
);
889 switch (cmsg
->cmsg_type
) {
892 struct in_pktinfo
*i
= (struct in_pktinfo
*) CMSG_DATA(cmsg
);
895 p
->ifindex
= i
->ipi_ifindex
;
897 p
->destination
.in
= i
->ipi_addr
;
902 p
->ttl
= *(int *) CMSG_DATA(cmsg
);
908 /* The Linux kernel sets the interface index to the loopback
909 * device if the packet came from the local host since it
910 * avoids the routing table in such a case. Let's unset the
911 * interface index in such a case. */
912 if (p
->ifindex
== LOOPBACK_IFINDEX
)
915 if (protocol
!= DNS_PROTOCOL_DNS
) {
916 /* If we don't know the interface index still, we look for the
917 * first local interface with a matching address. Yuck! */
919 p
->ifindex
= manager_find_ifindex(m
, p
->family
, &p
->destination
);
928 static int sendmsg_loop(int fd
, struct msghdr
*mh
, int flags
) {
935 if (sendmsg(fd
, mh
, flags
) >= 0)
944 r
= fd_wait_for_event(fd
, POLLOUT
, SEND_TIMEOUT_USEC
);
952 static int write_loop(int fd
, void *message
, size_t length
) {
959 if (write(fd
, message
, length
) >= 0)
968 r
= fd_wait_for_event(fd
, POLLOUT
, SEND_TIMEOUT_USEC
);
976 int manager_write(Manager
*m
, int fd
, DnsPacket
*p
) {
979 log_debug("Sending %s packet with id %u", DNS_PACKET_QR(p
) ? "response" : "query", DNS_PACKET_ID(p
));
981 r
= write_loop(fd
, DNS_PACKET_DATA(p
), p
->size
);
988 static int manager_ipv4_send(Manager
*m
, int fd
, int ifindex
, const struct in_addr
*addr
, uint16_t port
, DnsPacket
*p
) {
989 union sockaddr_union sa
= {
990 .in
.sin_family
= AF_INET
,
993 struct cmsghdr header
; /* For alignment */
994 uint8_t buffer
[CMSG_SPACE(sizeof(struct in_pktinfo
))];
996 struct msghdr mh
= {};
1005 iov
.iov_base
= DNS_PACKET_DATA(p
);
1006 iov
.iov_len
= p
->size
;
1008 sa
.in
.sin_addr
= *addr
;
1009 sa
.in
.sin_port
= htobe16(port
),
1013 mh
.msg_name
= &sa
.sa
;
1014 mh
.msg_namelen
= sizeof(sa
.in
);
1017 struct cmsghdr
*cmsg
;
1018 struct in_pktinfo
*pi
;
1022 mh
.msg_control
= &control
;
1023 mh
.msg_controllen
= CMSG_LEN(sizeof(struct in_pktinfo
));
1025 cmsg
= CMSG_FIRSTHDR(&mh
);
1026 cmsg
->cmsg_len
= mh
.msg_controllen
;
1027 cmsg
->cmsg_level
= IPPROTO_IP
;
1028 cmsg
->cmsg_type
= IP_PKTINFO
;
1030 pi
= (struct in_pktinfo
*) CMSG_DATA(cmsg
);
1031 pi
->ipi_ifindex
= ifindex
;
1034 return sendmsg_loop(fd
, &mh
, 0);
1037 static int manager_ipv6_send(Manager
*m
, int fd
, int ifindex
, const struct in6_addr
*addr
, uint16_t port
, DnsPacket
*p
) {
1038 union sockaddr_union sa
= {
1039 .in6
.sin6_family
= AF_INET6
,
1042 struct cmsghdr header
; /* For alignment */
1043 uint8_t buffer
[CMSG_SPACE(sizeof(struct in6_pktinfo
))];
1045 struct msghdr mh
= {};
1054 iov
.iov_base
= DNS_PACKET_DATA(p
);
1055 iov
.iov_len
= p
->size
;
1057 sa
.in6
.sin6_addr
= *addr
;
1058 sa
.in6
.sin6_port
= htobe16(port
),
1059 sa
.in6
.sin6_scope_id
= ifindex
;
1063 mh
.msg_name
= &sa
.sa
;
1064 mh
.msg_namelen
= sizeof(sa
.in6
);
1067 struct cmsghdr
*cmsg
;
1068 struct in6_pktinfo
*pi
;
1072 mh
.msg_control
= &control
;
1073 mh
.msg_controllen
= CMSG_LEN(sizeof(struct in6_pktinfo
));
1075 cmsg
= CMSG_FIRSTHDR(&mh
);
1076 cmsg
->cmsg_len
= mh
.msg_controllen
;
1077 cmsg
->cmsg_level
= IPPROTO_IPV6
;
1078 cmsg
->cmsg_type
= IPV6_PKTINFO
;
1080 pi
= (struct in6_pktinfo
*) CMSG_DATA(cmsg
);
1081 pi
->ipi6_ifindex
= ifindex
;
1084 return sendmsg_loop(fd
, &mh
, 0);
1087 int manager_send(Manager
*m
, int fd
, int ifindex
, int family
, const union in_addr_union
*addr
, uint16_t port
, DnsPacket
*p
) {
1094 log_debug("Sending %s packet with id %u on interface %i/%s", DNS_PACKET_QR(p
) ? "response" : "query", DNS_PACKET_ID(p
), ifindex
, af_to_name(family
));
1096 if (family
== AF_INET
)
1097 return manager_ipv4_send(m
, fd
, ifindex
, &addr
->in
, port
, p
);
1098 else if (family
== AF_INET6
)
1099 return manager_ipv6_send(m
, fd
, ifindex
, &addr
->in6
, port
, p
);
1101 return -EAFNOSUPPORT
;
1104 DnsServer
* manager_find_dns_server(Manager
*m
, int family
, const union in_addr_union
*in_addr
) {
1110 LIST_FOREACH(servers
, s
, m
->dns_servers
)
1111 if (s
->family
== family
&& in_addr_equal(family
, &s
->address
, in_addr
) > 0)
1114 LIST_FOREACH(servers
, s
, m
->fallback_dns_servers
)
1115 if (s
->family
== family
&& in_addr_equal(family
, &s
->address
, in_addr
) > 0)
1121 DnsServer
*manager_set_dns_server(Manager
*m
, DnsServer
*s
) {
1124 if (m
->current_dns_server
== s
)
1128 _cleanup_free_
char *ip
= NULL
;
1130 in_addr_to_string(s
->family
, &s
->address
, &ip
);
1131 log_info("Switching to system DNS server %s.", strna(ip
));
1134 m
->current_dns_server
= s
;
1136 if (m
->unicast_scope
)
1137 dns_cache_flush(&m
->unicast_scope
->cache
);
1142 DnsServer
*manager_get_dns_server(Manager
*m
) {
1146 /* Try to read updates resolv.conf */
1147 manager_read_resolv_conf(m
);
1149 if (!m
->current_dns_server
)
1150 manager_set_dns_server(m
, m
->dns_servers
);
1152 if (!m
->current_dns_server
) {
1156 /* No DNS servers configured, let's see if there are
1157 * any on any links. If not, we use the fallback
1160 HASHMAP_FOREACH(l
, m
->links
, i
)
1161 if (l
->dns_servers
) {
1167 manager_set_dns_server(m
, m
->fallback_dns_servers
);
1170 return m
->current_dns_server
;
1173 void manager_next_dns_server(Manager
*m
) {
1176 /* If there's currently no DNS server set, then the next
1177 * manager_get_dns_server() will find one */
1178 if (!m
->current_dns_server
)
1181 /* Change to the next one */
1182 if (m
->current_dns_server
->servers_next
) {
1183 manager_set_dns_server(m
, m
->current_dns_server
->servers_next
);
1187 /* If there was no next one, then start from the beginning of
1189 if (m
->current_dns_server
->type
== DNS_SERVER_FALLBACK
)
1190 manager_set_dns_server(m
, m
->fallback_dns_servers
);
1192 manager_set_dns_server(m
, m
->dns_servers
);
1195 uint32_t manager_find_mtu(Manager
*m
) {
1200 /* If we don't know on which link a DNS packet would be
1201 * delivered, let's find the largest MTU that works on all
1202 * interfaces we know of */
1204 HASHMAP_FOREACH(l
, m
->links
, i
) {
1208 if (mtu
<= 0 || l
->mtu
< mtu
)
1215 int manager_find_ifindex(Manager
*m
, int family
, const union in_addr_union
*in_addr
) {
1220 a
= manager_find_link_address(m
, family
, in_addr
);
1222 return a
->link
->ifindex
;
1227 void manager_refresh_rrs(Manager
*m
) {
1233 m
->host_ipv4_key
= dns_resource_key_unref(m
->host_ipv4_key
);
1234 m
->host_ipv6_key
= dns_resource_key_unref(m
->host_ipv6_key
);
1236 HASHMAP_FOREACH(l
, m
->links
, i
) {
1237 link_add_rrs(l
, true);
1238 link_add_rrs(l
, false);
1242 int manager_next_hostname(Manager
*m
) {
1249 p
= strchr(m
->hostname
, 0);
1252 while (p
> m
->hostname
) {
1253 if (!strchr("0123456789", p
[-1]))
1259 if (*p
== 0 || safe_atou64(p
, &u
) < 0 || u
<= 0)
1262 /* Add a random number to the old value. This way we can avoid
1263 * that two hosts pick the same hostname, win on IPv4 and lose
1264 * on IPv6 (or vice versa), and pick the same hostname
1265 * replacement hostname, ad infinitum. We still want the
1266 * numbers to go up monotonically, hence we just add a random
1269 random_bytes(&a
, sizeof(a
));
1272 if (asprintf(&h
, "%.*s%" PRIu64
, (int) (p
- m
->hostname
), m
->hostname
, u
) < 0)
1275 log_info("Hostname conflict, changing published hostname from '%s' to '%s'.", m
->hostname
, h
);
1280 manager_refresh_rrs(m
);
1285 LinkAddress
* manager_find_link_address(Manager
*m
, int family
, const union in_addr_union
*in_addr
) {
1291 HASHMAP_FOREACH(l
, m
->links
, i
) {
1294 a
= link_find_address(l
, family
, in_addr
);
1302 bool manager_our_packet(Manager
*m
, DnsPacket
*p
) {
1306 return !!manager_find_link_address(m
, p
->family
, &p
->sender
);
1309 DnsScope
* manager_find_scope(Manager
*m
, DnsPacket
*p
) {
1315 l
= hashmap_get(m
->links
, INT_TO_PTR(p
->ifindex
));
1319 if (p
->protocol
== DNS_PROTOCOL_LLMNR
) {
1320 if (p
->family
== AF_INET
)
1321 return l
->llmnr_ipv4_scope
;
1322 else if (p
->family
== AF_INET6
)
1323 return l
->llmnr_ipv6_scope
;
1329 void manager_verify_all(Manager
*m
) {
1334 LIST_FOREACH(scopes
, s
, m
->dns_scopes
)
1335 dns_zone_verify_all(&s
->zone
);
1338 void manager_flush_dns_servers(Manager
*m
, DnsServerType t
) {
1343 if (t
== DNS_SERVER_SYSTEM
)
1344 while (m
->dns_servers
) {
1347 LIST_REMOVE(servers
, m
->dns_servers
, s
);
1348 dns_server_unref(s
);
1351 if (t
== DNS_SERVER_FALLBACK
)
1352 while (m
->fallback_dns_servers
) {
1353 s
= m
->fallback_dns_servers
;
1355 LIST_REMOVE(servers
, m
->fallback_dns_servers
, s
);
1356 dns_server_unref(s
);
1360 static const char* const support_table
[_SUPPORT_MAX
] = {
1361 [SUPPORT_NO
] = "no",
1362 [SUPPORT_YES
] = "yes",
1363 [SUPPORT_RESOLVE
] = "resolve",
1365 DEFINE_STRING_TABLE_LOOKUP(support
, Support
);