if (r < 0)
return r;
- r = manager_llmnr_ipv6_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;
- r = manager_llmnr_ipv6_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;
log_warning("There appears to be another LLMNR respondering running. Turning off LLMNR support.");
m->llmnr_support = SUPPORT_NO;
manager_llmnr_stop(m);
+
return 0;
}
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);
return r;
}
-static void write_resolve_conf_server(DnsServer *s, FILE *f, unsigned *count) {
+static void write_resolv_conf_server(DnsServer *s, FILE *f, unsigned *count) {
_cleanup_free_ char *t = NULL;
int r;
}
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 *length, unsigned *count) {
+ 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) ++;
+}
+
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;
+ _cleanup_set_free_ Set *dns = NULL, *domains = NULL;
unsigned count = 0;
DnsServer *s;
Iterator i;
/* Read the system /etc/resolv.conf first */
manager_read_resolv_conf(m);
+ /* Add the full list to a set, to filter out duplicates */
+ dns = set_new(dns_server_hash_func, dns_server_compare_func);
+ if (!dns)
+ return -ENOMEM;
+
+ domains = set_new(dns_name_hash_func, dns_name_compare_func);
+ if (!domains)
+ return -ENOMEM;
+
+ /* 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;
+
+ STRV_FOREACH(domain, l->unicast_scope->domains) {
+ r = set_put(domains, *domain);
+ if (r == -EEXIST)
+ continue;
+ if (r < 0)
+ return r;
+ }
+ }
+
+ /* 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 = fopen_temporary(path, &f, &temp_path);
if (r < 0)
return r;
"# resolv.conf(5) in a different way, replace the symlink by a\n"
"# static file or a different symlink.\n\n", f);
- LIST_FOREACH(servers, s, m->dns_servers)
- write_resolve_conf_server(s, f, &count);
+ if (set_isempty(dns))
+ fputs("# No DNS servers known.\n", f);
+ else {
+ SET_FOREACH(s, dns, i)
+ write_resolv_conf_server(s, f, &count);
+ }
+
+ if (!set_isempty(domains)) {
+ unsigned length = 0;
+ char *domain;
- HASHMAP_FOREACH(l, m->links, i)
- LIST_FOREACH(servers, s, l->dns_servers)
- write_resolve_conf_server(s, f, &count);
+ count = 0;
- if (count == 0) {
- LIST_FOREACH(servers, s, m->fallback_dns_servers)
- write_resolve_conf_server(s, f, &count);
+ fputs("search", f);
+ SET_FOREACH(domain, domains, i)
+ write_resolv_conf_search(domain, f, &count, &length);
+ fputs("\n", f);
}
r = fflush_and_check(f);
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;
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