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-rw-r--r--src/resolve/resolved-manager.c1533
1 files changed, 1533 insertions, 0 deletions
diff --git a/src/resolve/resolved-manager.c b/src/resolve/resolved-manager.c
new file mode 100644
index 0000000..b3d35c8
--- /dev/null
+++ b/src/resolve/resolved-manager.c
@@ -0,0 +1,1533 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include <netinet/in.h>
+#include <poll.h>
+#include <stdio_ext.h>
+#include <sys/ioctl.h>
+
+#if HAVE_LIBIDN2
+#include <idn2.h>
+#endif
+
+#include "af-list.h"
+#include "alloc-util.h"
+#include "dirent-util.h"
+#include "dns-domain.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "hostname-util.h"
+#include "io-util.h"
+#include "missing_network.h"
+#include "netlink-util.h"
+#include "network-internal.h"
+#include "ordered-set.h"
+#include "parse-util.h"
+#include "random-util.h"
+#include "resolved-bus.h"
+#include "resolved-conf.h"
+#include "resolved-dns-stub.h"
+#include "resolved-dnssd.h"
+#include "resolved-etc-hosts.h"
+#include "resolved-llmnr.h"
+#include "resolved-manager.h"
+#include "resolved-mdns.h"
+#include "resolved-resolv-conf.h"
+#include "socket-util.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "utf8.h"
+
+#define SEND_TIMEOUT_USEC (200 * USEC_PER_MSEC)
+
+static int manager_process_link(sd_netlink *rtnl, sd_netlink_message *mm, void *userdata) {
+ Manager *m = userdata;
+ uint16_t type;
+ Link *l;
+ int ifindex, r;
+
+ assert(rtnl);
+ assert(m);
+ assert(mm);
+
+ r = sd_netlink_message_get_type(mm, &type);
+ if (r < 0)
+ goto fail;
+
+ r = sd_rtnl_message_link_get_ifindex(mm, &ifindex);
+ if (r < 0)
+ goto fail;
+
+ l = hashmap_get(m->links, INT_TO_PTR(ifindex));
+
+ switch (type) {
+
+ case RTM_NEWLINK:{
+ bool is_new = !l;
+
+ if (!l) {
+ r = link_new(m, &l, ifindex);
+ if (r < 0)
+ goto fail;
+ }
+
+ r = link_process_rtnl(l, mm);
+ if (r < 0)
+ goto fail;
+
+ r = link_update(l);
+ if (r < 0)
+ goto fail;
+
+ if (is_new)
+ log_debug("Found new link %i/%s", ifindex, l->name);
+
+ break;
+ }
+
+ case RTM_DELLINK:
+ if (l) {
+ log_debug("Removing link %i/%s", l->ifindex, l->name);
+ link_remove_user(l);
+ link_free(l);
+ }
+
+ break;
+ }
+
+ return 0;
+
+fail:
+ log_warning_errno(r, "Failed to process RTNL link message: %m");
+ return 0;
+}
+
+static int manager_process_address(sd_netlink *rtnl, sd_netlink_message *mm, void *userdata) {
+ Manager *m = userdata;
+ union in_addr_union address;
+ uint16_t type;
+ int r, ifindex, family;
+ LinkAddress *a;
+ Link *l;
+
+ assert(rtnl);
+ assert(mm);
+ assert(m);
+
+ r = sd_netlink_message_get_type(mm, &type);
+ if (r < 0)
+ goto fail;
+
+ r = sd_rtnl_message_addr_get_ifindex(mm, &ifindex);
+ if (r < 0)
+ goto fail;
+
+ l = hashmap_get(m->links, INT_TO_PTR(ifindex));
+ if (!l)
+ return 0;
+
+ r = sd_rtnl_message_addr_get_family(mm, &family);
+ if (r < 0)
+ goto fail;
+
+ switch (family) {
+
+ case AF_INET:
+ r = sd_netlink_message_read_in_addr(mm, IFA_LOCAL, &address.in);
+ if (r < 0) {
+ r = sd_netlink_message_read_in_addr(mm, IFA_ADDRESS, &address.in);
+ if (r < 0)
+ goto fail;
+ }
+
+ break;
+
+ case AF_INET6:
+ r = sd_netlink_message_read_in6_addr(mm, IFA_LOCAL, &address.in6);
+ if (r < 0) {
+ r = sd_netlink_message_read_in6_addr(mm, IFA_ADDRESS, &address.in6);
+ if (r < 0)
+ goto fail;
+ }
+
+ break;
+
+ default:
+ return 0;
+ }
+
+ a = link_find_address(l, family, &address);
+
+ switch (type) {
+
+ case RTM_NEWADDR:
+
+ if (!a) {
+ r = link_address_new(l, &a, family, &address);
+ if (r < 0)
+ return r;
+ }
+
+ r = link_address_update_rtnl(a, mm);
+ if (r < 0)
+ return r;
+
+ break;
+
+ case RTM_DELADDR:
+ link_address_free(a);
+ break;
+ }
+
+ return 0;
+
+fail:
+ log_warning_errno(r, "Failed to process RTNL address message: %m");
+ return 0;
+}
+
+static int manager_rtnl_listen(Manager *m) {
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
+ sd_netlink_message *i;
+ int r;
+
+ assert(m);
+
+ /* First, subscribe to interfaces coming and going */
+ r = sd_netlink_open(&m->rtnl);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_attach_event(m->rtnl, m->event, SD_EVENT_PRIORITY_IMPORTANT);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_add_match(m->rtnl, NULL, RTM_NEWLINK, manager_process_link, NULL, m, "resolve-NEWLINK");
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_add_match(m->rtnl, NULL, RTM_DELLINK, manager_process_link, NULL, m, "resolve-DELLINK");
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_add_match(m->rtnl, NULL, RTM_NEWADDR, manager_process_address, NULL, m, "resolve-NEWADDR");
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_add_match(m->rtnl, NULL, RTM_DELADDR, manager_process_address, NULL, m, "resolve-DELADDR");
+ if (r < 0)
+ return r;
+
+ /* Then, enumerate all links */
+ r = sd_rtnl_message_new_link(m->rtnl, &req, RTM_GETLINK, 0);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_request_dump(req, true);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_call(m->rtnl, req, 0, &reply);
+ if (r < 0)
+ return r;
+
+ for (i = reply; i; i = sd_netlink_message_next(i)) {
+ r = manager_process_link(m->rtnl, i, m);
+ if (r < 0)
+ return r;
+ }
+
+ req = sd_netlink_message_unref(req);
+ reply = sd_netlink_message_unref(reply);
+
+ /* Finally, enumerate all addresses, too */
+ r = sd_rtnl_message_new_addr(m->rtnl, &req, RTM_GETADDR, 0, AF_UNSPEC);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_request_dump(req, true);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_call(m->rtnl, req, 0, &reply);
+ if (r < 0)
+ return r;
+
+ for (i = reply; i; i = sd_netlink_message_next(i)) {
+ r = manager_process_address(m->rtnl, i, m);
+ if (r < 0)
+ return r;
+ }
+
+ return r;
+}
+
+static int on_network_event(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ Manager *m = userdata;
+ Iterator i;
+ Link *l;
+ int r;
+
+ assert(m);
+
+ sd_network_monitor_flush(m->network_monitor);
+
+ HASHMAP_FOREACH(l, m->links, i) {
+ r = link_update(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to update monitor information for %i: %m", l->ifindex);
+ }
+
+ (void) manager_write_resolv_conf(m);
+
+ return 0;
+}
+
+static int manager_network_monitor_listen(Manager *m) {
+ int r, fd, events;
+
+ assert(m);
+
+ r = sd_network_monitor_new(&m->network_monitor, NULL);
+ if (r < 0)
+ return r;
+
+ fd = sd_network_monitor_get_fd(m->network_monitor);
+ if (fd < 0)
+ return fd;
+
+ events = sd_network_monitor_get_events(m->network_monitor);
+ if (events < 0)
+ return events;
+
+ r = sd_event_add_io(m->event, &m->network_event_source, fd, events, &on_network_event, m);
+ if (r < 0)
+ return r;
+
+ r = sd_event_source_set_priority(m->network_event_source, SD_EVENT_PRIORITY_IMPORTANT+5);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_source_set_description(m->network_event_source, "network-monitor");
+
+ return 0;
+}
+
+static int determine_hostname(char **full_hostname, char **llmnr_hostname, char **mdns_hostname) {
+ _cleanup_free_ char *h = NULL, *n = NULL;
+#if HAVE_LIBIDN2
+ _cleanup_free_ char *utf8 = NULL;
+#elif HAVE_LIBIDN
+ int k;
+#endif
+ char label[DNS_LABEL_MAX];
+ const char *p, *decoded;
+ int r;
+
+ assert(full_hostname);
+ assert(llmnr_hostname);
+ assert(mdns_hostname);
+
+ /* Extract and normalize the first label of the locally configured hostname, and check it's not "localhost". */
+
+ r = gethostname_strict(&h);
+ if (r < 0)
+ return log_debug_errno(r, "Can't determine system hostname: %m");
+
+ p = h;
+ r = dns_label_unescape(&p, label, sizeof label, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to unescape host name: %m");
+ if (r == 0)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Couldn't find a single label in hostname.");
+
+#if HAVE_LIBIDN2
+ r = idn2_to_unicode_8z8z(label, &utf8, 0);
+ if (r != IDN2_OK)
+ return log_error("Failed to undo IDNA: %s", idn2_strerror(r));
+ assert(utf8_is_valid(utf8));
+
+ r = strlen(utf8);
+ decoded = utf8;
+#elif HAVE_LIBIDN
+ k = dns_label_undo_idna(label, r, label, sizeof label);
+ if (k < 0)
+ return log_error_errno(k, "Failed to undo IDNA: %m");
+ if (k > 0)
+ r = k;
+
+ if (!utf8_is_valid(label))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "System hostname is not UTF-8 clean.");
+ decoded = label;
+#else
+ decoded = label; /* no decoding */
+#endif
+
+ r = dns_label_escape_new(decoded, r, &n);
+ if (r < 0)
+ return log_error_errno(r, "Failed to escape host name: %m");
+
+ if (is_localhost(n))
+ return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
+ "System hostname is 'localhost', ignoring.");
+
+ r = dns_name_concat(n, "local", 0, mdns_hostname);
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine mDNS hostname: %m");
+
+ *llmnr_hostname = TAKE_PTR(n);
+ *full_hostname = TAKE_PTR(h);
+
+ return 0;
+}
+
+static const char *fallback_hostname(void) {
+
+ /* Determine the fall back hostname. For exposing this system to the outside world, we cannot have it to be
+ * "localhost" even if that's the compiled in hostname. In this case, let's revert to "linux" instead. */
+
+ if (is_localhost(FALLBACK_HOSTNAME))
+ return "linux";
+
+ return FALLBACK_HOSTNAME;
+}
+
+static int make_fallback_hostnames(char **full_hostname, char **llmnr_hostname, char **mdns_hostname) {
+ _cleanup_free_ char *n = NULL, *m = NULL;
+ char label[DNS_LABEL_MAX], *h;
+ const char *p;
+ int r;
+
+ assert(full_hostname);
+ assert(llmnr_hostname);
+ assert(mdns_hostname);
+
+ p = fallback_hostname();
+ r = dns_label_unescape(&p, label, sizeof label, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to unescape fallback host name: %m");
+
+ assert(r > 0); /* The fallback hostname must have at least one label */
+
+ r = dns_label_escape_new(label, r, &n);
+ if (r < 0)
+ return log_error_errno(r, "Failed to escape fallback hostname: %m");
+
+ r = dns_name_concat(n, "local", 0, &m);
+ if (r < 0)
+ return log_error_errno(r, "Failed to concatenate mDNS hostname: %m");
+
+ h = strdup(fallback_hostname());
+ if (!h)
+ return log_oom();
+
+ *llmnr_hostname = TAKE_PTR(n);
+ *mdns_hostname = TAKE_PTR(m);
+
+ *full_hostname = h;
+
+ return 0;
+}
+
+static int on_hostname_change(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
+ _cleanup_free_ char *full_hostname = NULL, *llmnr_hostname = NULL, *mdns_hostname = NULL;
+ Manager *m = userdata;
+ int r;
+
+ assert(m);
+
+ r = determine_hostname(&full_hostname, &llmnr_hostname, &mdns_hostname);
+ if (r < 0)
+ return 0; /* ignore invalid hostnames */
+
+ if (streq(full_hostname, m->full_hostname) &&
+ streq(llmnr_hostname, m->llmnr_hostname) &&
+ streq(mdns_hostname, m->mdns_hostname))
+ return 0;
+
+ log_info("System hostname changed to '%s'.", full_hostname);
+
+ free_and_replace(m->full_hostname, full_hostname);
+ free_and_replace(m->llmnr_hostname, llmnr_hostname);
+ free_and_replace(m->mdns_hostname, mdns_hostname);
+
+ manager_refresh_rrs(m);
+
+ return 0;
+}
+
+static int manager_watch_hostname(Manager *m) {
+ int r;
+
+ assert(m);
+
+ m->hostname_fd = open("/proc/sys/kernel/hostname",
+ O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);
+ if (m->hostname_fd < 0) {
+ log_warning_errno(errno, "Failed to watch hostname: %m");
+ return 0;
+ }
+
+ r = sd_event_add_io(m->event, &m->hostname_event_source, m->hostname_fd, 0, on_hostname_change, m);
+ if (r < 0) {
+ if (r == -EPERM)
+ /* kernels prior to 3.2 don't support polling this file. Ignore the failure. */
+ m->hostname_fd = safe_close(m->hostname_fd);
+ else
+ return log_error_errno(r, "Failed to add hostname event source: %m");
+ }
+
+ (void) sd_event_source_set_description(m->hostname_event_source, "hostname");
+
+ r = determine_hostname(&m->full_hostname, &m->llmnr_hostname, &m->mdns_hostname);
+ if (r < 0) {
+ log_info("Defaulting to hostname '%s'.", fallback_hostname());
+
+ r = make_fallback_hostnames(&m->full_hostname, &m->llmnr_hostname, &m->mdns_hostname);
+ if (r < 0)
+ return r;
+ } else
+ log_info("Using system hostname '%s'.", m->full_hostname);
+
+ return 0;
+}
+
+static int manager_sigusr1(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
+ _cleanup_free_ char *buffer = NULL;
+ _cleanup_fclose_ FILE *f = NULL;
+ Manager *m = userdata;
+ DnsServer *server;
+ size_t size = 0;
+ DnsScope *scope;
+ Iterator i;
+ Link *l;
+
+ assert(s);
+ assert(si);
+ assert(m);
+
+ f = open_memstream(&buffer, &size);
+ if (!f)
+ return log_oom();
+
+ (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
+
+ LIST_FOREACH(scopes, scope, m->dns_scopes)
+ dns_scope_dump(scope, f);
+
+ LIST_FOREACH(servers, server, m->dns_servers)
+ dns_server_dump(server, f);
+ LIST_FOREACH(servers, server, m->fallback_dns_servers)
+ dns_server_dump(server, f);
+ HASHMAP_FOREACH(l, m->links, i)
+ LIST_FOREACH(servers, server, l->dns_servers)
+ dns_server_dump(server, f);
+
+ if (fflush_and_check(f) < 0)
+ return log_oom();
+
+ log_dump(LOG_INFO, buffer);
+ return 0;
+}
+
+static int manager_sigusr2(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
+ Manager *m = userdata;
+
+ assert(s);
+ assert(si);
+ assert(m);
+
+ manager_flush_caches(m);
+
+ return 0;
+}
+
+static int manager_sigrtmin1(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
+ Manager *m = userdata;
+
+ assert(s);
+ assert(si);
+ assert(m);
+
+ manager_reset_server_features(m);
+ return 0;
+}
+
+int manager_new(Manager **ret) {
+ _cleanup_(manager_freep) Manager *m = NULL;
+ int r;
+
+ assert(ret);
+
+ m = new(Manager, 1);
+ if (!m)
+ return -ENOMEM;
+
+ *m = (Manager) {
+ .llmnr_ipv4_udp_fd = -1,
+ .llmnr_ipv6_udp_fd = -1,
+ .llmnr_ipv4_tcp_fd = -1,
+ .llmnr_ipv6_tcp_fd = -1,
+ .mdns_ipv4_fd = -1,
+ .mdns_ipv6_fd = -1,
+ .dns_stub_udp_fd = -1,
+ .dns_stub_tcp_fd = -1,
+ .hostname_fd = -1,
+
+ .llmnr_support = RESOLVE_SUPPORT_YES,
+ .mdns_support = RESOLVE_SUPPORT_YES,
+ .dnssec_mode = DEFAULT_DNSSEC_MODE,
+ .dns_over_tls_mode = DEFAULT_DNS_OVER_TLS_MODE,
+ .enable_cache = true,
+ .dns_stub_listener_mode = DNS_STUB_LISTENER_YES,
+ .read_resolv_conf = true,
+ .need_builtin_fallbacks = true,
+ .etc_hosts_last = USEC_INFINITY,
+ .etc_hosts_mtime = USEC_INFINITY,
+ .read_etc_hosts = true,
+ };
+
+ r = dns_trust_anchor_load(&m->trust_anchor);
+ if (r < 0)
+ return r;
+
+ r = manager_parse_config_file(m);
+ if (r < 0)
+ log_warning_errno(r, "Failed to parse configuration file: %m");
+
+ r = sd_event_default(&m->event);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL);
+ (void) sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL);
+
+ (void) sd_event_set_watchdog(m->event, true);
+
+ r = manager_watch_hostname(m);
+ if (r < 0)
+ return r;
+
+ r = dnssd_load(m);
+ if (r < 0)
+ log_warning_errno(r, "Failed to load DNS-SD configuration files: %m");
+
+ r = dns_scope_new(m, &m->unicast_scope, NULL, DNS_PROTOCOL_DNS, AF_UNSPEC);
+ if (r < 0)
+ return r;
+
+ r = manager_network_monitor_listen(m);
+ if (r < 0)
+ return r;
+
+ r = manager_rtnl_listen(m);
+ if (r < 0)
+ return r;
+
+ r = manager_connect_bus(m);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_add_signal(m->event, &m->sigusr1_event_source, SIGUSR1, manager_sigusr1, m);
+ (void) sd_event_add_signal(m->event, &m->sigusr2_event_source, SIGUSR2, manager_sigusr2, m);
+ (void) sd_event_add_signal(m->event, &m->sigrtmin1_event_source, SIGRTMIN+1, manager_sigrtmin1, m);
+
+ manager_cleanup_saved_user(m);
+
+ *ret = TAKE_PTR(m);
+
+ return 0;
+}
+
+int manager_start(Manager *m) {
+ int r;
+
+ assert(m);
+
+ r = manager_dns_stub_start(m);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+Manager *manager_free(Manager *m) {
+ Link *l;
+ DnssdService *s;
+
+ if (!m)
+ return NULL;
+
+ dns_server_unlink_all(m->dns_servers);
+ dns_server_unlink_all(m->fallback_dns_servers);
+ dns_search_domain_unlink_all(m->search_domains);
+
+ while ((l = hashmap_first(m->links)))
+ link_free(l);
+
+ while (m->dns_queries)
+ dns_query_free(m->dns_queries);
+
+ dns_scope_free(m->unicast_scope);
+
+ /* At this point only orphaned streams should remain. All others should have been freed already by their
+ * owners */
+ while (m->dns_streams)
+ dns_stream_unref(m->dns_streams);
+
+ hashmap_free(m->links);
+ hashmap_free(m->dns_transactions);
+
+ sd_event_source_unref(m->network_event_source);
+ sd_network_monitor_unref(m->network_monitor);
+
+ sd_netlink_unref(m->rtnl);
+ sd_event_source_unref(m->rtnl_event_source);
+
+ manager_llmnr_stop(m);
+ manager_mdns_stop(m);
+ manager_dns_stub_stop(m);
+
+ sd_bus_flush_close_unref(m->bus);
+
+ sd_event_source_unref(m->sigusr1_event_source);
+ sd_event_source_unref(m->sigusr2_event_source);
+ sd_event_source_unref(m->sigrtmin1_event_source);
+
+ sd_event_unref(m->event);
+
+ dns_resource_key_unref(m->llmnr_host_ipv4_key);
+ dns_resource_key_unref(m->llmnr_host_ipv6_key);
+ dns_resource_key_unref(m->mdns_host_ipv4_key);
+ dns_resource_key_unref(m->mdns_host_ipv6_key);
+
+ sd_event_source_unref(m->hostname_event_source);
+ safe_close(m->hostname_fd);
+
+ free(m->full_hostname);
+ free(m->llmnr_hostname);
+ free(m->mdns_hostname);
+
+ while ((s = hashmap_first(m->dnssd_services)))
+ dnssd_service_free(s);
+ hashmap_free(m->dnssd_services);
+
+ dns_trust_anchor_flush(&m->trust_anchor);
+ manager_etc_hosts_flush(m);
+
+ return mfree(m);
+}
+
+int manager_recv(Manager *m, int fd, DnsProtocol protocol, DnsPacket **ret) {
+ _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+ union {
+ struct cmsghdr header; /* For alignment */
+ uint8_t buffer[CMSG_SPACE(MAXSIZE(struct in_pktinfo, struct in6_pktinfo))
+ + CMSG_SPACE(int) /* ttl/hoplimit */
+ + EXTRA_CMSG_SPACE /* kernel appears to require extra buffer space */];
+ } control;
+ union sockaddr_union sa;
+ struct iovec iov;
+ struct msghdr mh = {
+ .msg_name = &sa.sa,
+ .msg_namelen = sizeof(sa),
+ .msg_iov = &iov,
+ .msg_iovlen = 1,
+ .msg_control = &control,
+ .msg_controllen = sizeof(control),
+ };
+ struct cmsghdr *cmsg;
+ ssize_t ms, l;
+ int r;
+
+ assert(m);
+ assert(fd >= 0);
+ assert(ret);
+
+ ms = next_datagram_size_fd(fd);
+ if (ms < 0)
+ return ms;
+
+ r = dns_packet_new(&p, protocol, ms, DNS_PACKET_SIZE_MAX);
+ if (r < 0)
+ return r;
+
+ iov = IOVEC_MAKE(DNS_PACKET_DATA(p), p->allocated);
+
+ l = recvmsg(fd, &mh, 0);
+ if (l < 0) {
+ if (IN_SET(errno, EAGAIN, EINTR))
+ return 0;
+
+ return -errno;
+ }
+ if (l == 0)
+ return 0;
+
+ assert(!(mh.msg_flags & MSG_CTRUNC));
+ assert(!(mh.msg_flags & MSG_TRUNC));
+
+ p->size = (size_t) l;
+
+ p->family = sa.sa.sa_family;
+ p->ipproto = IPPROTO_UDP;
+ if (p->family == AF_INET) {
+ p->sender.in = sa.in.sin_addr;
+ p->sender_port = be16toh(sa.in.sin_port);
+ } else if (p->family == AF_INET6) {
+ p->sender.in6 = sa.in6.sin6_addr;
+ p->sender_port = be16toh(sa.in6.sin6_port);
+ p->ifindex = sa.in6.sin6_scope_id;
+ } else
+ return -EAFNOSUPPORT;
+
+ CMSG_FOREACH(cmsg, &mh) {
+
+ if (cmsg->cmsg_level == IPPROTO_IPV6) {
+ assert(p->family == AF_INET6);
+
+ switch (cmsg->cmsg_type) {
+
+ case IPV6_PKTINFO: {
+ struct in6_pktinfo *i = (struct in6_pktinfo*) CMSG_DATA(cmsg);
+
+ if (p->ifindex <= 0)
+ p->ifindex = i->ipi6_ifindex;
+
+ p->destination.in6 = i->ipi6_addr;
+ break;
+ }
+
+ case IPV6_HOPLIMIT:
+ p->ttl = *(int *) CMSG_DATA(cmsg);
+ break;
+
+ }
+ } else if (cmsg->cmsg_level == IPPROTO_IP) {
+ assert(p->family == AF_INET);
+
+ switch (cmsg->cmsg_type) {
+
+ case IP_PKTINFO: {
+ struct in_pktinfo *i = (struct in_pktinfo*) CMSG_DATA(cmsg);
+
+ if (p->ifindex <= 0)
+ p->ifindex = i->ipi_ifindex;
+
+ p->destination.in = i->ipi_addr;
+ break;
+ }
+
+ case IP_TTL:
+ p->ttl = *(int *) CMSG_DATA(cmsg);
+ break;
+ }
+ }
+ }
+
+ /* The Linux kernel sets the interface index to the loopback
+ * device if the packet came from the local host since it
+ * avoids the routing table in such a case. Let's unset the
+ * interface index in such a case. */
+ if (p->ifindex == LOOPBACK_IFINDEX)
+ p->ifindex = 0;
+
+ if (protocol != DNS_PROTOCOL_DNS) {
+ /* If we don't know the interface index still, we look for the
+ * first local interface with a matching address. Yuck! */
+ if (p->ifindex <= 0)
+ p->ifindex = manager_find_ifindex(m, p->family, &p->destination);
+ }
+
+ *ret = TAKE_PTR(p);
+
+ return 1;
+}
+
+static int sendmsg_loop(int fd, struct msghdr *mh, int flags) {
+ int r;
+
+ assert(fd >= 0);
+ assert(mh);
+
+ for (;;) {
+ if (sendmsg(fd, mh, flags) >= 0)
+ return 0;
+
+ if (errno == EINTR)
+ continue;
+
+ if (errno != EAGAIN)
+ return -errno;
+
+ r = fd_wait_for_event(fd, POLLOUT, SEND_TIMEOUT_USEC);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -ETIMEDOUT;
+ }
+}
+
+static int write_loop(int fd, void *message, size_t length) {
+ int r;
+
+ assert(fd >= 0);
+ assert(message);
+
+ for (;;) {
+ if (write(fd, message, length) >= 0)
+ return 0;
+
+ if (errno == EINTR)
+ continue;
+
+ if (errno != EAGAIN)
+ return -errno;
+
+ r = fd_wait_for_event(fd, POLLOUT, SEND_TIMEOUT_USEC);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -ETIMEDOUT;
+ }
+}
+
+int manager_write(Manager *m, int fd, DnsPacket *p) {
+ int r;
+
+ log_debug("Sending %s packet with id %" PRIu16 ".", DNS_PACKET_QR(p) ? "response" : "query", DNS_PACKET_ID(p));
+
+ r = write_loop(fd, DNS_PACKET_DATA(p), p->size);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+static int manager_ipv4_send(
+ Manager *m,
+ int fd,
+ int ifindex,
+ const struct in_addr *destination,
+ uint16_t port,
+ const struct in_addr *source,
+ DnsPacket *p) {
+ union {
+ struct cmsghdr header; /* For alignment */
+ uint8_t buffer[CMSG_SPACE(sizeof(struct in_pktinfo))];
+ } control = {};
+ union sockaddr_union sa;
+ struct iovec iov;
+ struct msghdr mh = {
+ .msg_iov = &iov,
+ .msg_iovlen = 1,
+ .msg_name = &sa.sa,
+ .msg_namelen = sizeof(sa.in),
+ };
+
+ assert(m);
+ assert(fd >= 0);
+ assert(destination);
+ assert(port > 0);
+ assert(p);
+
+ iov = IOVEC_MAKE(DNS_PACKET_DATA(p), p->size);
+
+ sa = (union sockaddr_union) {
+ .in.sin_family = AF_INET,
+ .in.sin_addr = *destination,
+ .in.sin_port = htobe16(port),
+ };
+
+ if (ifindex > 0) {
+ struct cmsghdr *cmsg;
+ struct in_pktinfo *pi;
+
+ mh.msg_control = &control;
+ mh.msg_controllen = CMSG_LEN(sizeof(struct in_pktinfo));
+
+ cmsg = CMSG_FIRSTHDR(&mh);
+ cmsg->cmsg_len = mh.msg_controllen;
+ cmsg->cmsg_level = IPPROTO_IP;
+ cmsg->cmsg_type = IP_PKTINFO;
+
+ pi = (struct in_pktinfo*) CMSG_DATA(cmsg);
+ pi->ipi_ifindex = ifindex;
+
+ if (source)
+ pi->ipi_spec_dst = *source;
+ }
+
+ return sendmsg_loop(fd, &mh, 0);
+}
+
+static int manager_ipv6_send(
+ Manager *m,
+ int fd,
+ int ifindex,
+ const struct in6_addr *destination,
+ uint16_t port,
+ const struct in6_addr *source,
+ DnsPacket *p) {
+
+ union {
+ struct cmsghdr header; /* For alignment */
+ uint8_t buffer[CMSG_SPACE(sizeof(struct in6_pktinfo))];
+ } control = {};
+ union sockaddr_union sa;
+ struct iovec iov;
+ struct msghdr mh = {
+ .msg_iov = &iov,
+ .msg_iovlen = 1,
+ .msg_name = &sa.sa,
+ .msg_namelen = sizeof(sa.in6),
+ };
+
+ assert(m);
+ assert(fd >= 0);
+ assert(destination);
+ assert(port > 0);
+ assert(p);
+
+ iov = IOVEC_MAKE(DNS_PACKET_DATA(p), p->size);
+
+ sa = (union sockaddr_union) {
+ .in6.sin6_family = AF_INET6,
+ .in6.sin6_addr = *destination,
+ .in6.sin6_port = htobe16(port),
+ .in6.sin6_scope_id = ifindex,
+ };
+
+ if (ifindex > 0) {
+ struct cmsghdr *cmsg;
+ struct in6_pktinfo *pi;
+
+ mh.msg_control = &control;
+ mh.msg_controllen = CMSG_LEN(sizeof(struct in6_pktinfo));
+
+ cmsg = CMSG_FIRSTHDR(&mh);
+ cmsg->cmsg_len = mh.msg_controllen;
+ cmsg->cmsg_level = IPPROTO_IPV6;
+ cmsg->cmsg_type = IPV6_PKTINFO;
+
+ pi = (struct in6_pktinfo*) CMSG_DATA(cmsg);
+ pi->ipi6_ifindex = ifindex;
+
+ if (source)
+ pi->ipi6_addr = *source;
+ }
+
+ return sendmsg_loop(fd, &mh, 0);
+}
+
+int manager_send(
+ Manager *m,
+ int fd,
+ int ifindex,
+ int family,
+ const union in_addr_union *destination,
+ uint16_t port,
+ const union in_addr_union *source,
+ DnsPacket *p) {
+
+ assert(m);
+ assert(fd >= 0);
+ assert(destination);
+ assert(port > 0);
+ assert(p);
+
+ log_debug("Sending %s packet with id %" PRIu16 " on interface %i/%s.", DNS_PACKET_QR(p) ? "response" : "query", DNS_PACKET_ID(p), ifindex, af_to_name(family));
+
+ if (family == AF_INET)
+ return manager_ipv4_send(m, fd, ifindex, &destination->in, port, source ? &source->in : NULL, p);
+ if (family == AF_INET6)
+ return manager_ipv6_send(m, fd, ifindex, &destination->in6, port, source ? &source->in6 : NULL, p);
+
+ return -EAFNOSUPPORT;
+}
+
+uint32_t manager_find_mtu(Manager *m) {
+ uint32_t mtu = 0;
+ Link *l;
+ Iterator i;
+
+ /* If we don't know on which link a DNS packet would be
+ * delivered, let's find the largest MTU that works on all
+ * interfaces we know of */
+
+ HASHMAP_FOREACH(l, m->links, i) {
+ if (l->mtu <= 0)
+ continue;
+
+ if (mtu <= 0 || l->mtu < mtu)
+ mtu = l->mtu;
+ }
+
+ return mtu;
+}
+
+int manager_find_ifindex(Manager *m, int family, const union in_addr_union *in_addr) {
+ LinkAddress *a;
+
+ assert(m);
+
+ a = manager_find_link_address(m, family, in_addr);
+ if (a)
+ return a->link->ifindex;
+
+ return 0;
+}
+
+void manager_refresh_rrs(Manager *m) {
+ Iterator i;
+ Link *l;
+ DnssdService *s;
+
+ assert(m);
+
+ m->llmnr_host_ipv4_key = dns_resource_key_unref(m->llmnr_host_ipv4_key);
+ m->llmnr_host_ipv6_key = dns_resource_key_unref(m->llmnr_host_ipv6_key);
+ m->mdns_host_ipv4_key = dns_resource_key_unref(m->mdns_host_ipv4_key);
+ m->mdns_host_ipv6_key = dns_resource_key_unref(m->mdns_host_ipv6_key);
+
+ if (m->mdns_support == RESOLVE_SUPPORT_YES)
+ HASHMAP_FOREACH(s, m->dnssd_services, i)
+ if (dnssd_update_rrs(s) < 0)
+ log_warning("Failed to refresh DNS-SD service '%s'", s->name);
+
+ HASHMAP_FOREACH(l, m->links, i) {
+ link_add_rrs(l, true);
+ link_add_rrs(l, false);
+ }
+}
+
+static int manager_next_random_name(const char *old, char **ret_new) {
+ const char *p;
+ uint64_t u, a;
+ char *n;
+
+ p = strchr(old, 0);
+ assert(p);
+
+ while (p > old) {
+ if (!strchr(DIGITS, p[-1]))
+ break;
+
+ p--;
+ }
+
+ if (*p == 0 || safe_atou64(p, &u) < 0 || u <= 0)
+ u = 1;
+
+ /* Add a random number to the old value. This way we can avoid
+ * that two hosts pick the same hostname, win on IPv4 and lose
+ * on IPv6 (or vice versa), and pick the same hostname
+ * replacement hostname, ad infinitum. We still want the
+ * numbers to go up monotonically, hence we just add a random
+ * value 1..10 */
+
+ random_bytes(&a, sizeof(a));
+ u += 1 + a % 10;
+
+ if (asprintf(&n, "%.*s%" PRIu64, (int) (p - old), old, u) < 0)
+ return -ENOMEM;
+
+ *ret_new = n;
+
+ return 0;
+}
+
+int manager_next_hostname(Manager *m) {
+ _cleanup_free_ char *h = NULL, *k = NULL;
+ int r;
+
+ assert(m);
+
+ r = manager_next_random_name(m->llmnr_hostname, &h);
+ if (r < 0)
+ return r;
+
+ r = dns_name_concat(h, "local", 0, &k);
+ if (r < 0)
+ return r;
+
+ log_info("Hostname conflict, changing published hostname from '%s' to '%s'.", m->llmnr_hostname, h);
+
+ free_and_replace(m->llmnr_hostname, h);
+ free_and_replace(m->mdns_hostname, k);
+
+ manager_refresh_rrs(m);
+
+ return 0;
+}
+
+LinkAddress* manager_find_link_address(Manager *m, int family, const union in_addr_union *in_addr) {
+ Iterator i;
+ Link *l;
+
+ assert(m);
+
+ HASHMAP_FOREACH(l, m->links, i) {
+ LinkAddress *a;
+
+ a = link_find_address(l, family, in_addr);
+ if (a)
+ return a;
+ }
+
+ return NULL;
+}
+
+bool manager_our_packet(Manager *m, DnsPacket *p) {
+ assert(m);
+ assert(p);
+
+ return !!manager_find_link_address(m, p->family, &p->sender);
+}
+
+DnsScope* manager_find_scope(Manager *m, DnsPacket *p) {
+ Link *l;
+
+ assert(m);
+ assert(p);
+
+ l = hashmap_get(m->links, INT_TO_PTR(p->ifindex));
+ if (!l)
+ return NULL;
+
+ switch (p->protocol) {
+ case DNS_PROTOCOL_LLMNR:
+ if (p->family == AF_INET)
+ return l->llmnr_ipv4_scope;
+ else if (p->family == AF_INET6)
+ return l->llmnr_ipv6_scope;
+
+ break;
+
+ case DNS_PROTOCOL_MDNS:
+ if (p->family == AF_INET)
+ return l->mdns_ipv4_scope;
+ else if (p->family == AF_INET6)
+ return l->mdns_ipv6_scope;
+
+ break;
+
+ default:
+ break;
+ }
+
+ return NULL;
+}
+
+void manager_verify_all(Manager *m) {
+ DnsScope *s;
+
+ assert(m);
+
+ LIST_FOREACH(scopes, s, m->dns_scopes)
+ dns_zone_verify_all(&s->zone);
+}
+
+int manager_is_own_hostname(Manager *m, const char *name) {
+ int r;
+
+ assert(m);
+ assert(name);
+
+ if (m->llmnr_hostname) {
+ r = dns_name_equal(name, m->llmnr_hostname);
+ if (r != 0)
+ return r;
+ }
+
+ if (m->mdns_hostname) {
+ r = dns_name_equal(name, m->mdns_hostname);
+ if (r != 0)
+ return r;
+ }
+
+ if (m->full_hostname)
+ return dns_name_equal(name, m->full_hostname);
+
+ return 0;
+}
+
+int manager_compile_dns_servers(Manager *m, OrderedSet **dns) {
+ DnsServer *s;
+ Iterator i;
+ Link *l;
+ int r;
+
+ assert(m);
+ assert(dns);
+
+ r = ordered_set_ensure_allocated(dns, &dns_server_hash_ops);
+ if (r < 0)
+ return r;
+
+ /* First add the system-wide servers and domains */
+ LIST_FOREACH(servers, s, m->dns_servers) {
+ r = ordered_set_put(*dns, s);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+
+ /* Then, add the per-link servers */
+ HASHMAP_FOREACH(l, m->links, i) {
+ LIST_FOREACH(servers, s, l->dns_servers) {
+ r = ordered_set_put(*dns, s);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+ }
+
+ /* If we found nothing, add the fallback servers */
+ if (ordered_set_isempty(*dns)) {
+ LIST_FOREACH(servers, s, m->fallback_dns_servers) {
+ r = ordered_set_put(*dns, s);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+ }
+
+ return 0;
+}
+
+/* filter_route is a tri-state:
+ * < 0: no filtering
+ * = 0 or false: return only domains which should be used for searching
+ * > 0 or true: return only domains which are for routing only
+ */
+int manager_compile_search_domains(Manager *m, OrderedSet **domains, int filter_route) {
+ DnsSearchDomain *d;
+ Iterator i;
+ Link *l;
+ int r;
+
+ assert(m);
+ assert(domains);
+
+ r = ordered_set_ensure_allocated(domains, &dns_name_hash_ops);
+ if (r < 0)
+ return r;
+
+ LIST_FOREACH(domains, d, m->search_domains) {
+
+ if (filter_route >= 0 &&
+ d->route_only != !!filter_route)
+ continue;
+
+ r = ordered_set_put(*domains, d->name);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+
+ HASHMAP_FOREACH(l, m->links, i) {
+
+ LIST_FOREACH(domains, d, l->search_domains) {
+
+ if (filter_route >= 0 &&
+ d->route_only != !!filter_route)
+ continue;
+
+ r = ordered_set_put(*domains, d->name);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+ }
+
+ return 0;
+}
+
+DnssecMode manager_get_dnssec_mode(Manager *m) {
+ assert(m);
+
+ if (m->dnssec_mode != _DNSSEC_MODE_INVALID)
+ return m->dnssec_mode;
+
+ return DNSSEC_NO;
+}
+
+bool manager_dnssec_supported(Manager *m) {
+ DnsServer *server;
+ Iterator i;
+ Link *l;
+
+ assert(m);
+
+ if (manager_get_dnssec_mode(m) == DNSSEC_NO)
+ return false;
+
+ server = manager_get_dns_server(m);
+ if (server && !dns_server_dnssec_supported(server))
+ return false;
+
+ HASHMAP_FOREACH(l, m->links, i)
+ if (!link_dnssec_supported(l))
+ return false;
+
+ return true;
+}
+
+DnsOverTlsMode manager_get_dns_over_tls_mode(Manager *m) {
+ assert(m);
+
+ if (m->dns_over_tls_mode != _DNS_OVER_TLS_MODE_INVALID)
+ return m->dns_over_tls_mode;
+
+ return DNS_OVER_TLS_NO;
+}
+
+void manager_dnssec_verdict(Manager *m, DnssecVerdict verdict, const DnsResourceKey *key) {
+
+ assert(verdict >= 0);
+ assert(verdict < _DNSSEC_VERDICT_MAX);
+
+ if (DEBUG_LOGGING) {
+ char s[DNS_RESOURCE_KEY_STRING_MAX];
+
+ log_debug("Found verdict for lookup %s: %s",
+ dns_resource_key_to_string(key, s, sizeof s),
+ dnssec_verdict_to_string(verdict));
+ }
+
+ m->n_dnssec_verdict[verdict]++;
+}
+
+bool manager_routable(Manager *m, int family) {
+ Iterator i;
+ Link *l;
+
+ assert(m);
+
+ /* Returns true if the host has at least one interface with a routable address of the specified type */
+
+ HASHMAP_FOREACH(l, m->links, i)
+ if (link_relevant(l, family, false))
+ return true;
+
+ return false;
+}
+
+void manager_flush_caches(Manager *m) {
+ DnsScope *scope;
+
+ assert(m);
+
+ LIST_FOREACH(scopes, scope, m->dns_scopes)
+ dns_cache_flush(&scope->cache);
+
+ log_info("Flushed all caches.");
+}
+
+void manager_reset_server_features(Manager *m) {
+ Iterator i;
+ Link *l;
+
+ dns_server_reset_features_all(m->dns_servers);
+ dns_server_reset_features_all(m->fallback_dns_servers);
+
+ HASHMAP_FOREACH(l, m->links, i)
+ dns_server_reset_features_all(l->dns_servers);
+
+ log_info("Resetting learnt feature levels on all servers.");
+}
+
+void manager_cleanup_saved_user(Manager *m) {
+ _cleanup_closedir_ DIR *d = NULL;
+ struct dirent *de;
+ int r;
+
+ assert(m);
+
+ /* Clean up all saved per-link files in /run/systemd/resolve/netif/ that don't have a matching interface
+ * anymore. These files are created to persist settings pushed in by the user via the bus, so that resolved can
+ * be restarted without losing this data. */
+
+ d = opendir("/run/systemd/resolve/netif/");
+ if (!d) {
+ if (errno == ENOENT)
+ return;
+
+ log_warning_errno(errno, "Failed to open interface directory: %m");
+ return;
+ }
+
+ FOREACH_DIRENT_ALL(de, d, log_error_errno(errno, "Failed to read interface directory: %m")) {
+ _cleanup_free_ char *p = NULL;
+ int ifindex;
+ Link *l;
+
+ if (!IN_SET(de->d_type, DT_UNKNOWN, DT_REG))
+ continue;
+
+ if (dot_or_dot_dot(de->d_name))
+ continue;
+
+ r = parse_ifindex(de->d_name, &ifindex);
+ if (r < 0) /* Probably some temporary file from a previous run. Delete it */
+ goto rm;
+
+ l = hashmap_get(m->links, INT_TO_PTR(ifindex));
+ if (!l) /* link vanished */
+ goto rm;
+
+ if (l->is_managed) /* now managed by networkd, hence the bus settings are useless */
+ goto rm;
+
+ continue;
+
+ rm:
+ p = strappend("/run/systemd/resolve/netif/", de->d_name);
+ if (!p) {
+ log_oom();
+ return;
+ }
+
+ (void) unlink(p);
+ }
+}
+
+bool manager_next_dnssd_names(Manager *m) {
+ Iterator i;
+ DnssdService *s;
+ bool tried = false;
+ int r;
+
+ assert(m);
+
+ HASHMAP_FOREACH(s, m->dnssd_services, i) {
+ _cleanup_free_ char * new_name = NULL;
+
+ if (!s->withdrawn)
+ continue;
+
+ r = manager_next_random_name(s->name_template, &new_name);
+ if (r < 0) {
+ log_warning_errno(r, "Failed to get new name for service '%s': %m", s->name);
+ continue;
+ }
+
+ free_and_replace(s->name_template, new_name);
+
+ s->withdrawn = false;
+
+ tried = true;
+ }
+
+ if (tried)
+ manager_refresh_rrs(m);
+
+ return tried;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 03:07:17 +0000