1 files changed, 99 insertions, 0 deletions
diff --git a/vala-xmpp/src/module/tls.vala b/vala-xmpp/src/module/tls.vala
new file mode 100644
index 00000000..1f8447ec
--- /dev/null
+++ b/vala-xmpp/src/module/tls.vala
@@ -0,0 +1,99 @@
+using Xmpp.Core;
+
+namespace Xmpp.Tls {
+    private const string NS_URI = "urn:ietf:params:xml:ns:xmpp-tls";
+
+    public class Module : XmppStreamNegotiationModule {
+        public const string ID = "tls_module";
+
+        public bool require { get; set; default = true; }
+        public bool server_supports_tls = false;
+        public bool server_requires_tls = false;
+        public SocketConnectable? identity = null;
+
+        public override void attach(XmppStream stream) {
+            stream.received_features_node.connect(this.received_features_node);
+            stream.received_nonza.connect(this.received_nonza);
+        }
+
+        public override void detach(XmppStream stream) {
+            stream.received_features_node.disconnect(this.received_features_node);
+            stream.received_nonza.disconnect(this.received_nonza);
+        }
+
+        private void received_nonza(XmppStream stream, StanzaNode node) {
+            if (node.ns_uri == NS_URI && node.name == "proceed") {
+                try {
+                    var conn = TlsClientConnection.new(stream.get_stream(), identity);
+                    // TODO: Add certificate error handling, that is, allow the
+                    // program to handle certificate errors. The certificate
+                    // *is checked* by TlsClientConnection, and connection is
+                    // not allowed to continue in case that there is an error.
+                    stream.reset_stream(conn);
+
+                    var flag = Flag.get_flag(stream);
+                    flag.peer_certificate = conn.get_peer_certificate();
+                    flag.finished = true;
+                } catch (Error e) {
+                    stderr.printf("Failed to start TLS: %s\n", e.message);
+                }
+            }
+        }
+
+        private void received_features_node(XmppStream stream) {
+            if (Flag.has_flag(stream)) return;
+            if (stream.is_setup_needed()) return;
+
+            var starttls = stream.features.get_subnode("starttls", NS_URI);
+            if (starttls != null) {
+                server_supports_tls = true;
+                if (starttls.get_subnode("required") != null || stream.features.get_all_subnodes().size == 1) {
+                    server_requires_tls = true;
+                }
+                if (server_requires_tls || require) {
+                    try {
+                        stream.write(new StanzaNode.build("starttls", NS_URI).add_self_xmlns());
+                    } catch (IOStreamError e) {
+                        stderr.printf("Failed to request TLS: %s\n", e.message);
+                    }
+                }
+                if (identity == null) {
+                    identity = new NetworkService("xmpp-client", "tcp", stream.remote_name);
+                }
+                stream.add_flag(new Flag());
+            }
+        }
+
+        public static Module? get_module(XmppStream stream) {
+            return (Module?) stream.get_module(NS_URI, ID);
+        }
+
+        public override bool mandatory_outstanding(XmppStream stream) {
+            return require && (!Flag.has_flag(stream) || !Flag.get_flag(stream).finished);
+        }
+
+        public override bool negotiation_active(XmppStream stream) {
+            return Flag.has_flag(stream) && !Flag.get_flag(stream).finished;
+        }
+
+        public override string get_ns() { return NS_URI; }
+        public override string get_id() { return ID; }
+    }
+
+    public class Flag : XmppStreamFlag {
+        public const string ID = "tls_flag";
+        public TlsCertificate? peer_certificate;
+        public bool finished = false;
+
+        public static Flag? get_flag(XmppStream stream) {
+            return (Flag?) stream.get_flag(NS_URI, ID);
+        }
+
+        public static bool has_flag(XmppStream stream) {
+            return get_flag(stream) != null;
+        }
+
+        public override string get_ns() { return NS_URI; }
+        public override string get_id() { return ID; }
+    }
+}