resolved: move TLS data shared by all servers to manager

Instead of having a context and/or trusted CA list per server this is now moved to the server. Ensures future TLS configuration options are global instead of per server.

src/resolve/resolved-dns-server.c

@@ -82,10 +82,6 @@ int dns_server_new(
 
         s->linked = true;
 
-#if ENABLE_DNS_OVER_TLS
-        dnstls_server_init(s);
-#endif
-
         /* A new DNS server that isn't fallback is added and the one
          * we used so far was a fallback one? Then let's try to pick
          * the new one */

src/resolve/resolved-dnstls-gnutls.c

@@ -41,7 +41,7 @@ int dnstls_stream_connect_tls(DnsStream *stream, DnsServer *server) {
         if (r < 0)
                 return r;
 
-        r = gnutls_credentials_set(gs, GNUTLS_CRD_CERTIFICATE, server->dnstls_data.cert_cred);
+        r = gnutls_credentials_set(gs, GNUTLS_CRD_CERTIFICATE, stream->manager->dnstls_data.cert_cred);
         if (r < 0)
                 return r;
 
@@ -187,19 +187,26 @@ ssize_t dnstls_stream_read(DnsStream *stream, void *buf, size_t count) {
         return ss;
 }
 
-void dnstls_server_init(DnsServer *server) {
-        assert(server);
-
-        /* Do not verify cerificate */
-        gnutls_certificate_allocate_credentials(&server->dnstls_data.cert_cred);
-}
-
 void dnstls_server_free(DnsServer *server) {
         assert(server);
 
-        if (server->dnstls_data.cert_cred)
-                gnutls_certificate_free_credentials(server->dnstls_data.cert_cred);
-
         if (server->dnstls_data.session_data.data)
                 gnutls_free(server->dnstls_data.session_data.data);
 }
+
+void dnstls_manager_init(Manager *manager) {
+        int r;
+        assert(manager);
+
+        gnutls_certificate_allocate_credentials(&manager->dnstls_data.cert_cred);
+        r = gnutls_certificate_set_x509_trust_file(manager->dnstls_data.cert_cred, manager->trusted_certificate_file, GNUTLS_X509_FMT_PEM);
+        if (r < 0)
+                log_error("Failed to load trusted certificate file %s: %s", manager->trusted_certificate_file, gnutls_strerror(r));
+}
+
+void dnstls_manager_free(Manager *manager) {
+        assert(manager);
+
+        if (manager->dnstls_data.cert_cred)
+                gnutls_certificate_free_credentials(manager->dnstls_data.cert_cred);
+}

src/resolve/resolved-dnstls-gnutls.h

@@ -8,8 +8,11 @@
 #include <gnutls/gnutls.h>
 #include <stdbool.h>
 
-struct DnsTlsServerData {
+struct DnsTlsManagerData {
         gnutls_certificate_credentials_t cert_cred;
+};
+
+struct DnsTlsServerData {
         gnutls_datum_t session_data;
 };
 

src/resolve/resolved-dnstls-openssl.c

@@ -54,6 +54,7 @@ int dnstls_stream_connect_tls(DnsStream *stream, DnsServer *server) {
         int error, r;
 
         assert(stream);
+        assert(stream->manager);
         assert(server);
 
         rb = BIO_new_socket(stream->fd, 0);
@@ -67,7 +68,7 @@ int dnstls_stream_connect_tls(DnsStream *stream, DnsServer *server) {
         BIO_get_mem_ptr(wb, &stream->dnstls_data.write_buffer);
         stream->dnstls_data.buffer_offset = 0;
 
-        s = SSL_new(server->dnstls_data.ctx);
+        s = SSL_new(stream->manager->dnstls_data.ctx);
         if (!s)
                 return -ENOMEM;
 
@@ -336,22 +337,29 @@ ssize_t dnstls_stream_read(DnsStream *stream, void *buf, size_t count) {
         return ss;
 }
 
-void dnstls_server_init(DnsServer *server) {
-        assert(server);
-
-        server->dnstls_data.ctx = SSL_CTX_new(TLS_client_method());
-        if (server->dnstls_data.ctx) {
-                SSL_CTX_set_min_proto_version(server->dnstls_data.ctx, TLS1_2_VERSION);
-                SSL_CTX_set_options(server->dnstls_data.ctx, SSL_OP_NO_COMPRESSION);
-        }
-}
-
 void dnstls_server_free(DnsServer *server) {
         assert(server);
 
-        if (server->dnstls_data.ctx)
-                SSL_CTX_free(server->dnstls_data.ctx);
-
         if (server->dnstls_data.session)
                 SSL_SESSION_free(server->dnstls_data.session);
 }
+
+void dnstls_manager_init(Manager *manager) {
+        int r;
+        assert(manager);
+
+        ERR_load_crypto_strings();
+        SSL_load_error_strings();
+        manager->dnstls_data.ctx = SSL_CTX_new(TLS_client_method());
+        if (manager->dnstls_data.ctx) {
+                SSL_CTX_set_min_proto_version(manager->dnstls_data.ctx, TLS1_2_VERSION);
+                SSL_CTX_set_options(manager->dnstls_data.ctx, SSL_OP_NO_COMPRESSION);
+        }
+}
+
+void dnstls_manager_free(Manager *manager) {
+        assert(manager);
+
+        if (manager->dnstls_data.ctx)
+                SSL_CTX_free(manager->dnstls_data.ctx);
+}

src/resolve/resolved-dnstls-openssl.h

@@ -8,8 +8,11 @@
 #include <openssl/ssl.h>
 #include <stdbool.h>
 
-struct DnsTlsServerData {
+struct DnsTlsManagerData {
         SSL_CTX *ctx;
+};
+
+struct DnsTlsServerData {
         SSL_SESSION *session;
 };
 

src/resolve/resolved-dnstls.h

@@ -5,6 +5,7 @@
 #error This source file requires DNS-over-TLS to be enabled
 #endif
 
+typedef struct DnsTlsManagerData DnsTlsManagerData;
 typedef struct DnsTlsServerData DnsTlsServerData;
 typedef struct DnsTlsStreamData DnsTlsStreamData;
 
@@ -28,5 +29,7 @@ int dnstls_stream_shutdown(DnsStream *stream, int error);
 ssize_t dnstls_stream_write(DnsStream *stream, const char *buf, size_t count);
 ssize_t dnstls_stream_read(DnsStream *stream, void *buf, size_t count);
 
-void dnstls_server_init(DnsServer *server);
 void dnstls_server_free(DnsServer *server);
+
+void dnstls_manager_init(Manager *manager);
+void dnstls_manager_free(Manager *manager);

src/resolve/resolved-manager.c

@@ -597,6 +597,10 @@ int manager_new(Manager **ret) {
         if (r < 0)
                 log_warning_errno(r, "Failed to parse configuration file: %m");
 
+#if ENABLE_DNS_OVER_TLS
+        dnstls_manager_init(m);
+#endif
+
         r = sd_event_default(&m->event);
         if (r < 0)
                 return r;
@@ -677,6 +681,10 @@ Manager *manager_free(Manager *m) {
         while (m->dns_streams)
                 dns_stream_unref(m->dns_streams);
 
+#if ENABLE_DNS_OVER_TLS
+        dnstls_manager_free(m);
+#endif
+
         hashmap_free(m->links);
         hashmap_free(m->dns_transactions);
 

src/resolve/resolved-manager.h

@@ -18,6 +18,7 @@ typedef struct Manager Manager;
 #include "resolved-dns-server.h"
 #include "resolved-dns-stream.h"
 #include "resolved-dns-trust-anchor.h"
+#include "resolved-dnstls.h"
 #include "resolved-link.h"
 
 #define MANAGER_SEARCH_DOMAINS_MAX 256
@@ -39,6 +40,10 @@ struct Manager {
         bool enable_cache;
         DnsStubListenerMode dns_stub_listener_mode;
 
+#if ENABLE_DNS_OVER_TLS
+        DnsTlsManagerData dnstls_data;
+#endif
+
         /* Network */
         Hashmap *links;