#include "socket-util.h"
#include "af-list.h"
#include "utf8.h"
+#include "fileio-label.h"
#include "resolved-dns-domain.h"
#include "resolved-conf.h"
if (r < 0)
goto fail;
+ r = link_update_monitor(l);
+ if (r < 0)
+ goto fail;
+
if (is_new)
log_debug("Found new link %i/%s", ifindex, l->name);
return 0;
fail:
- log_warning("Failed to process RTNL link message: %s", strerror(-r));
+ log_warning_errno(r, "Failed to process RTNL link message: %m");
return 0;
}
return 0;
fail:
- log_warning("Failed to process RTNL address message: %s", strerror(-r));
+ log_warning_errno(r, "Failed to process RTNL address message: %m");
return 0;
}
-
static int manager_rtnl_listen(Manager *m) {
_cleanup_rtnl_message_unref_ sd_rtnl_message *req = NULL, *reply = NULL;
sd_rtnl_message *i;
HASHMAP_FOREACH(l, m->links, i) {
r = link_update_monitor(l);
if (r < 0)
- log_warning("Failed to update monitor information for %i: %s", l->ifindex, strerror(-r));
+ log_warning_errno(r, "Failed to update monitor information for %i: %m", l->ifindex);
}
r = manager_write_resolv_conf(m);
if (r < 0)
- log_warning("Could not update resolv.conf: %s", strerror(-r));
+ log_warning_errno(r, "Could not update resolv.conf: %m");
return 0;
}
}
static int manager_watch_hostname(Manager *m) {
- _cleanup_free_ char *h = NULL;
int r;
assert(m);
m->hostname_fd = open("/proc/sys/kernel/hostname", O_RDONLY|O_CLOEXEC|O_NDELAY|O_NOCTTY);
if (m->hostname_fd < 0) {
- log_warning("Failed to watch hostname: %m");
+ log_warning_errno(errno, "Failed to watch hostname: %m");
return 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 {
- log_error("Failed to add hostname event source: %s", strerror(-r));
- return r;
- }
+ else
+ return log_error_errno(r, "Failed to add hostname event source: %m");
}
r = determine_hostname(&m->hostname);
return 0;
}
+static void manager_llmnr_stop(Manager *m) {
+ assert(m);
+
+ m->llmnr_ipv4_udp_event_source = sd_event_source_unref(m->llmnr_ipv4_udp_event_source);
+ m->llmnr_ipv4_udp_fd = safe_close(m->llmnr_ipv4_udp_fd);
+
+ m->llmnr_ipv6_udp_event_source = sd_event_source_unref(m->llmnr_ipv6_udp_event_source);
+ m->llmnr_ipv6_udp_fd = safe_close(m->llmnr_ipv6_udp_fd);
+
+ m->llmnr_ipv4_tcp_event_source = sd_event_source_unref(m->llmnr_ipv4_tcp_event_source);
+ m->llmnr_ipv4_tcp_fd = safe_close(m->llmnr_ipv4_tcp_fd);
+
+ m->llmnr_ipv6_tcp_event_source = sd_event_source_unref(m->llmnr_ipv6_tcp_event_source);
+ m->llmnr_ipv6_tcp_fd = safe_close(m->llmnr_ipv6_tcp_fd);
+}
+
+static int manager_llmnr_start(Manager *m) {
+ int r;
+
+ assert(m);
+
+ if (m->llmnr_support == SUPPORT_NO)
+ return 0;
+
+ r = manager_llmnr_ipv4_udp_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+
+ r = manager_llmnr_ipv4_tcp_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+
+ if (socket_ipv6_is_supported()) {
+ r = manager_llmnr_ipv6_udp_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+
+ r = manager_llmnr_ipv6_tcp_fd(m);
+ if (r == -EADDRINUSE)
+ goto eaddrinuse;
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+
+eaddrinuse:
+ log_warning("There appears to be another LLMNR responder running. Turning off LLMNR support.");
+ m->llmnr_support = SUPPORT_NO;
+ manager_llmnr_stop(m);
+
+ return 0;
+}
+
int manager_new(Manager **ret) {
_cleanup_(manager_freep) Manager *m = NULL;
int r;
m->hostname_fd = -1;
m->llmnr_support = SUPPORT_YES;
+ m->read_resolv_conf = true;
r = manager_parse_dns_server(m, DNS_SERVER_FALLBACK, DNS_SERVERS);
if (r < 0)
if (r < 0)
return r;
- r = manager_llmnr_ipv4_udp_fd(m);
- if (r < 0)
- return r;
- r = manager_llmnr_ipv6_udp_fd(m);
- if (r < 0)
- return r;
- r = manager_llmnr_ipv4_tcp_fd(m);
- if (r < 0)
- return r;
- r = manager_llmnr_ipv6_tcp_fd(m);
- if (r < 0)
- return r;
-
*ret = m;
m = NULL;
return 0;
}
+int manager_start(Manager *m) {
+ int r;
+
+ assert(m);
+
+ r = manager_llmnr_start(m);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
Manager *manager_free(Manager *m) {
Link *l;
if (!m)
return NULL;
- while (m->dns_queries)
- dns_query_free(m->dns_queries);
-
- hashmap_free(m->dns_transactions);
-
while ((l = hashmap_first(m->links)))
link_free(l);
- hashmap_free(m->links);
+
+ while (m->dns_queries)
+ dns_query_free(m->dns_queries);
dns_scope_free(m->unicast_scope);
- while (m->dns_servers)
- dns_server_free(m->dns_servers);
- while (m->fallback_dns_servers)
- dns_server_free(m->fallback_dns_servers);
+ manager_flush_dns_servers(m, DNS_SERVER_SYSTEM);
+ manager_flush_dns_servers(m, DNS_SERVER_FALLBACK);
+
+ hashmap_free(m->links);
+ hashmap_free(m->dns_transactions);
sd_event_source_unref(m->network_event_source);
sd_network_monitor_unref(m->network_monitor);
safe_close(m->dns_ipv4_fd);
safe_close(m->dns_ipv6_fd);
- sd_event_source_unref(m->llmnr_ipv4_udp_event_source);
- sd_event_source_unref(m->llmnr_ipv6_udp_event_source);
- safe_close(m->llmnr_ipv4_udp_fd);
- safe_close(m->llmnr_ipv6_udp_fd);
-
- sd_event_source_unref(m->llmnr_ipv4_tcp_event_source);
- sd_event_source_unref(m->llmnr_ipv6_tcp_event_source);
- safe_close(m->llmnr_ipv4_tcp_fd);
- safe_close(m->llmnr_ipv6_tcp_fd);
+ manager_llmnr_stop(m);
+ sd_bus_slot_unref(m->prepare_for_sleep_slot);
sd_event_source_unref(m->bus_retry_event_source);
sd_bus_unref(m->bus);
return NULL;
}
-static void write_resolve_conf_server(DnsServer *s, FILE *f, unsigned *count) {
+int manager_read_resolv_conf(Manager *m) {
+ _cleanup_fclose_ FILE *f = NULL;
+ struct stat st, own;
+ char line[LINE_MAX];
+ DnsServer *s, *nx;
+ usec_t t;
+ int r;
+
+ assert(m);
+
+ /* Reads the system /etc/resolv.conf, if it exists and is not
+ * symlinked to our own resolv.conf instance */
+
+ if (!m->read_resolv_conf)
+ return 0;
+
+ r = stat("/etc/resolv.conf", &st);
+ if (r < 0) {
+ if (errno != ENOENT)
+ log_warning_errno(errno, "Failed to open /etc/resolv.conf: %m");
+ r = -errno;
+ goto clear;
+ }
+
+ /* Have we already seen the file? */
+ t = timespec_load(&st.st_mtim);
+ if (t == m->resolv_conf_mtime)
+ return 0;
+
+ m->resolv_conf_mtime = t;
+
+ /* Is it symlinked to our own file? */
+ if (stat("/run/systemd/resolve/resolv.conf", &own) >= 0 &&
+ st.st_dev == own.st_dev &&
+ st.st_ino == own.st_ino) {
+ r = 0;
+ goto clear;
+ }
+
+ f = fopen("/etc/resolv.conf", "re");
+ if (!f) {
+ if (errno != ENOENT)
+ log_warning_errno(errno, "Failed to open /etc/resolv.conf: %m");
+ r = -errno;
+ goto clear;
+ }
+
+ if (fstat(fileno(f), &st) < 0) {
+ log_error_errno(errno, "Failed to stat open file: %m");
+ r = -errno;
+ goto clear;
+ }
+
+ LIST_FOREACH(servers, s, m->dns_servers)
+ s->marked = true;
+
+ FOREACH_LINE(line, f, r = -errno; goto clear) {
+ union in_addr_union address;
+ int family;
+ char *l;
+ const char *a;
+
+ truncate_nl(line);
+
+ l = strstrip(line);
+ if (*l == '#' || *l == ';')
+ continue;
+
+ a = first_word(l, "nameserver");
+ if (!a)
+ continue;
+
+ r = in_addr_from_string_auto(a, &family, &address);
+ if (r < 0) {
+ log_warning("Failed to parse name server %s.", a);
+ continue;
+ }
+
+ LIST_FOREACH(servers, s, m->dns_servers)
+ if (s->family == family && in_addr_equal(family, &s->address, &address) > 0)
+ break;
+
+ if (s)
+ s->marked = false;
+ else {
+ r = dns_server_new(m, NULL, DNS_SERVER_SYSTEM, NULL, family, &address);
+ if (r < 0)
+ goto clear;
+ }
+ }
+
+ LIST_FOREACH_SAFE(servers, s, nx, m->dns_servers)
+ if (s->marked)
+ dns_server_free(s);
+
+ /* Whenever /etc/resolv.conf changes, start using the first
+ * DNS server of it. This is useful to deal with broken
+ * network managing implementations (like NetworkManager),
+ * that when connecting to a VPN place both the VPN DNS
+ * servers and the local ones in /etc/resolv.conf. Without
+ * resetting the DNS server to use back to the first entry we
+ * will continue to use the local one thus being unable to
+ * resolve VPN domains. */
+ manager_set_dns_server(m, m->dns_servers);
+
+ return 0;
+
+clear:
+ while (m->dns_servers)
+ dns_server_free(m->dns_servers);
+
+ return r;
+}
+
+static void write_resolv_conf_server(DnsServer *s, FILE *f, unsigned *count) {
_cleanup_free_ char *t = NULL;
int r;
r = in_addr_to_string(s->family, &s->address, &t);
if (r < 0) {
- log_warning("Invalid DNS address. Ignoring: %s", strerror(-r));
+ log_warning_errno(r, "Invalid DNS address. Ignoring: %m");
return;
}
if (*count == MAXNS)
- fputs("# Too many DNS servers configured, the following entries may be ignored\n", f);
+ fputs("# Too many DNS servers configured, the following entries may be ignored.\n", f);
fprintf(f, "nameserver %s\n", t);
(*count) ++;
}
+static void write_resolv_conf_search(const char *domain, FILE *f,
+ unsigned *count, unsigned *length) {
+ assert(domain);
+ assert(f);
+ assert(length);
+
+ if (*count >= MAXDNSRCH ||
+ *length + strlen(domain) > 256) {
+ if (*count == MAXDNSRCH)
+ fputs(" # Too many search domains configured, remaining ones ignored.", f);
+ if (*length <= 256)
+ fputs(" # Total length of all search domains is too long, remaining ones ignored.", f);
+
+ return;
+ }
+
+ fprintf(f, " %s", domain);
+
+ (*length) += strlen(domain);
+ (*count) ++;
+}
+
+static int write_resolv_conf_contents(FILE *f, Set *dns, Set *domains) {
+ Iterator i;
+
+ fputs("# This file is managed by systemd-resolved(8). Do not edit.\n#\n"
+ "# Third party programs must not access this file directly, but\n"
+ "# only through the symlink at /etc/resolv.conf. To manage\n"
+ "# resolv.conf(5) in a different way, replace the symlink by a\n"
+ "# static file or a different symlink.\n\n", f);
+
+ if (set_isempty(dns))
+ fputs("# No DNS servers known.\n", f);
+ else {
+ DnsServer *s;
+ unsigned count = 0;
+
+ SET_FOREACH(s, dns, i)
+ write_resolv_conf_server(s, f, &count);
+ }
+
+ if (!set_isempty(domains)) {
+ unsigned length = 0, count = 0;
+ char *domain;
+
+ fputs("search", f);
+ SET_FOREACH(domain, domains, i)
+ write_resolv_conf_search(domain, f, &count, &length);
+ fputs("\n", f);
+ }
+
+ return fflush_and_check(f);
+}
+
+
int manager_write_resolv_conf(Manager *m) {
static const char path[] = "/run/systemd/resolve/resolv.conf";
_cleanup_free_ char *temp_path = NULL;
_cleanup_fclose_ FILE *f = NULL;
- unsigned count = 0;
+ _cleanup_set_free_ Set *dns = NULL, *domains = NULL;
DnsServer *s;
Iterator i;
Link *l;
assert(m);
- r = fopen_temporary(path, &f, &temp_path);
- if (r < 0)
- return r;
+ /* Read the system /etc/resolv.conf first */
+ manager_read_resolv_conf(m);
- fchmod(fileno(f), 0644);
+ /* Add the full list to a set, to filter out duplicates */
+ dns = set_new(&dns_server_hash_ops);
+ if (!dns)
+ return -ENOMEM;
- fputs("# This file is managed by systemd-resolved(8). Do not edit.\n#\n"
- "# Third party programs must not access this file directly, but\n"
- "# only through the symlink at /etc/resolv.conf. To manage\n"
- "# resolv.conf(5) in a different way, replace the symlink by a\n"
- "# static file or a different symlink.\n\n", f);
+ domains = set_new(&dns_name_hash_ops);
+ if (!domains)
+ return -ENOMEM;
- LIST_FOREACH(servers, s, m->dns_servers)
- write_resolve_conf_server(s, f, &count);
+ /* First add the system-wide servers */
+ LIST_FOREACH(servers, s, m->dns_servers) {
+ r = set_put(dns, s);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+
+ /* Then, add the per-link servers and domains */
+ HASHMAP_FOREACH(l, m->links, i) {
+ char **domain;
+
+ LIST_FOREACH(servers, s, l->dns_servers) {
+ r = set_put(dns, s);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+
+ if (!l->unicast_scope)
+ continue;
- HASHMAP_FOREACH(l, m->links, i)
- LIST_FOREACH(servers, s, l->dns_servers)
- write_resolve_conf_server(s, f, &count);
+ STRV_FOREACH(domain, l->unicast_scope->domains) {
+ r = set_put(domains, *domain);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+ }
- if (count == 0) {
- LIST_FOREACH(servers, s, m->fallback_dns_servers)
- write_resolve_conf_server(s, f, &count);
+ /* If we found nothing, add the fallback servers */
+ if (set_isempty(dns)) {
+ LIST_FOREACH(servers, s, m->fallback_dns_servers) {
+ r = set_put(dns, s);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
}
- r = fflush_and_check(f);
+ r = fopen_temporary_label(path, path, &f, &temp_path);
+ if (r < 0)
+ return r;
+
+ fchmod(fileno(f), 0644);
+
+ r = write_resolv_conf_contents(f, dns, domains);
if (r < 0)
goto fail;
_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
union {
struct cmsghdr header; /* For alignment */
- uint8_t buffer[CMSG_SPACE(MAX(sizeof(struct in_pktinfo), sizeof(struct in6_pktinfo)))
+ 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;
* 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 > 0 && manager_ifindex_is_loopback(m, p->ifindex) != 0)
+ if (p->ifindex == LOOPBACK_IFINDEX)
p->ifindex = 0;
/* If we don't know the interface index still, we look for the
return -EAFNOSUPPORT;
}
-bool manager_known_dns_server(Manager *m, int family, const union in_addr_union *in_addr) {
+DnsServer* manager_find_dns_server(Manager *m, int family, const union in_addr_union *in_addr) {
DnsServer *s;
assert(m);
assert(in_addr);
LIST_FOREACH(servers, s, m->dns_servers)
- if (s->family == family && in_addr_equal(family, &s->address, in_addr))
- return true;
+ if (s->family == family && in_addr_equal(family, &s->address, in_addr) > 0)
+ return s;
LIST_FOREACH(servers, s, m->fallback_dns_servers)
- if (s->family == family && in_addr_equal(family, &s->address, in_addr))
- return true;
+ if (s->family == family && in_addr_equal(family, &s->address, in_addr) > 0)
+ return s;
- return false;
+ return NULL;
}
-static DnsServer *manager_set_dns_server(Manager *m, DnsServer *s) {
+DnsServer *manager_set_dns_server(Manager *m, DnsServer *s) {
assert(m);
if (m->current_dns_server == s)
in_addr_to_string(s->family, &s->address, &ip);
log_info("Switching to system DNS server %s.", strna(ip));
- } else
- log_info("No system DNS server set.");
+ }
m->current_dns_server = s;
+
+ if (m->unicast_scope)
+ dns_cache_flush(&m->unicast_scope->cache);
+
return s;
}
Link *l;
assert(m);
+ /* Try to read updates resolv.conf */
+ manager_read_resolv_conf(m);
+
if (!m->current_dns_server)
manager_set_dns_server(m, m->dns_servers);
_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
DnsTransaction *t = NULL;
Manager *m = userdata;
+ DnsScope *scope;
int r;
r = manager_recv(m, fd, DNS_PROTOCOL_LLMNR, &p);
if (r <= 0)
return r;
+ scope = manager_find_scope(m, p);
+ if (!scope) {
+ log_warning("Got LLMNR UDP packet on unknown scope. Ignoring.");
+ return 0;
+ }
+
if (dns_packet_validate_reply(p) > 0) {
log_debug("Got reply packet for id %u", DNS_PACKET_ID(p));
- t = hashmap_get(m->dns_transactions, UINT_TO_PTR(DNS_PACKET_ID(p)));
- if (!t)
- return 0;
-
- dns_transaction_process_reply(t, p);
-
- } else if (dns_packet_validate_query(p) > 0) {
- Link *l;
+ dns_scope_check_conflicts(scope, p);
- l = hashmap_get(m->links, INT_TO_PTR(p->ifindex));
- if (l) {
- DnsScope *scope = NULL;
+ t = hashmap_get(m->dns_transactions, UINT_TO_PTR(DNS_PACKET_ID(p)));
+ if (t)
+ dns_transaction_process_reply(t, p);
- if (p->family == AF_INET)
- scope = l->llmnr_ipv4_scope;
- else if (p->family == AF_INET6)
- scope = l->llmnr_ipv6_scope;
+ } else if (dns_packet_validate_query(p) > 0) {
+ log_debug("Got query packet for id %u", DNS_PACKET_ID(p));
- if (scope)
- dns_scope_process_query(scope, NULL, p);
- }
+ dns_scope_process_query(scope, NULL, p);
} else
- log_debug("Invalid LLMNR packet.");
+ log_debug("Invalid LLMNR UDP packet.");
return 0;
}
}
static int on_llmnr_stream_packet(DnsStream *s) {
- assert(s);
+ DnsScope *scope;
- if (dns_packet_validate_query(s->read_packet) > 0) {
- Link *l;
+ assert(s);
- l = hashmap_get(s->manager->links, INT_TO_PTR(s->read_packet->ifindex));
- if (l) {
- DnsScope *scope = NULL;
+ scope = manager_find_scope(s->manager, s->read_packet);
+ if (!scope) {
+ log_warning("Got LLMNR TCP packet on unknown scope. Ignroing.");
+ return 0;
+ }
- if (s->read_packet->family == AF_INET)
- scope = l->llmnr_ipv4_scope;
- else if (s->read_packet->family == AF_INET6)
- scope = l->llmnr_ipv6_scope;
+ if (dns_packet_validate_query(s->read_packet) > 0) {
+ log_debug("Got query packet for id %u", DNS_PACKET_ID(s->read_packet));
- if (scope) {
- dns_scope_process_query(scope, s, s->read_packet);
+ dns_scope_process_query(scope, s, s->read_packet);
- /* If no reply packet was set, we free the stream */
- if (s->write_packet)
- return 0;
- }
- }
- }
+ /* If no reply packet was set, we free the stream */
+ if (s->write_packet)
+ return 0;
+ } else
+ log_debug("Invalid LLMNR TCP packet.");
dns_stream_free(s);
return 0;
return r;
}
-int manager_ifindex_is_loopback(Manager *m, int ifindex) {
- Link *l;
- assert(m);
-
- if (ifindex <= 0)
- return -EINVAL;
-
- l = hashmap_get(m->links, INT_TO_PTR(ifindex));
- if (l->flags & IFF_LOOPBACK)
- return 1;
-
- return 0;
-}
-
int manager_find_ifindex(Manager *m, int family, const union in_addr_union *in_addr) {
LinkAddress *a;
int manager_next_hostname(Manager *m) {
const char *p;
- uint64_t u;
+ uint64_t u, a;
char *h;
assert(m);
if (*p == 0 || safe_atou64(p, &u) < 0 || u <= 0)
u = 1;
- u++;
+ /* 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(&h, "%.*s%" PRIu64, (int) (p - m->hostname), m->hostname, u) < 0)
return -ENOMEM;
return NULL;
}
-int manager_our_packet(Manager *m, DnsPacket *p) {
+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;
+
+ if (p->protocol == DNS_PROTOCOL_LLMNR) {
+ if (p->family == AF_INET)
+ return l->llmnr_ipv4_scope;
+ else if (p->family == AF_INET6)
+ return l->llmnr_ipv6_scope;
+ }
+
+ 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);
+}
+
+void manager_flush_dns_servers(Manager *m, DnsServerType t) {
+ assert(m);
+
+ if (t == DNS_SERVER_SYSTEM)
+ while (m->dns_servers)
+ dns_server_free(m->dns_servers);
+
+ if (t == DNS_SERVER_FALLBACK)
+ while (m->fallback_dns_servers)
+ dns_server_free(m->fallback_dns_servers);
+}
+
static const char* const support_table[_SUPPORT_MAX] = {
[SUPPORT_NO] = "no",
[SUPPORT_YES] = "yes",
~ianmdlvl / elogind.git / blobdiff