Move DLTS-SRTP into libdino

1 files changed, 146 insertions, 0 deletions

diff --git a/libdino/src/crypto/dtls_srtp.vala b/libdino/src/crypto/dtls_srtp.vala
new file mode 100644
index 00000000..884f1a43
--- /dev/null
+++ b/libdino/src/crypto/dtls_srtp.vala
@@ -0,0 +1,146 @@
+namespace Dino.Crypto.DtlsSrtp {
+
+public abstract class CredentialsCapsule : Object {
+    public uint8[] own_fingerprint;
+}
+
+public abstract class AbstractHandler {
+
+    public signal void send_data(uint8[] data);
+
+    public bool ready { get {
+        return srtp_session.has_encrypt && srtp_session.has_decrypt;
+    }}
+
+    public Mode mode { get; set; default = Mode.CLIENT; }
+    public uint8[] own_fingerprint { get; private set; }
+    public uint8[] peer_fingerprint { get; set; }
+    public string peer_fp_algo { get; set; }
+
+    protected CredentialsCapsule credentials;
+    protected Cond buffer_cond = Cond();
+    protected Mutex buffer_mutex = Mutex();
+    protected Gee.LinkedList<Bytes> buffer_queue = new Gee.LinkedList<Bytes>();
+
+    protected bool running = false;
+    protected bool stop = false;
+    protected bool restart = false;
+
+    protected Crypto.Srtp.Session srtp_session = new Crypto.Srtp.Session();
+
+    protected AbstractHandler.with_cert(CredentialsCapsule creds) {
+        this.credentials = creds;
+        this.own_fingerprint = creds.own_fingerprint;
+    }
+
+    public uint8[]? process_incoming_data(uint component_id, uint8[] data) throws Crypto.Error {
+        if (data[0] >= 128) {
+            if (!srtp_session.has_decrypt) {
+                debug("Received data before SRTP session is ready, dropping.");
+                return null;
+            }
+            if (component_id == 1) {
+                if (data.length >= 2 && data[1] >= 192 && data[1] < 224) {
+                    return srtp_session.decrypt_rtcp(data);
+                }
+                return srtp_session.decrypt_rtp(data);
+            }
+            if (component_id == 2) return srtp_session.decrypt_rtcp(data);
+        }
+        if (component_id == 1 && data.length >= 1 && (data[0] >= 20 && data[0] < 64)) {
+            on_data_rec(data);
+            return null;
+        }
+        debug("Dropping unknown data from component %u", component_id);
+        return null;
+    }
+
+    public uint8[]? process_outgoing_data(uint component_id, uint8[] data) throws Crypto.Error {
+        if (srtp_session.has_encrypt) {
+            if (component_id == 1) {
+                if (data.length >= 2 && data[1] >= 192 && data[1] < 224) {
+                    return srtp_session.encrypt_rtcp(data);
+                }
+                return srtp_session.encrypt_rtp(data);
+            }
+            if (component_id == 2) return srtp_session.encrypt_rtcp(data);
+        }
+        return null;
+    }
+
+    public void on_data_rec(owned uint8[] data) {
+        buffer_mutex.lock();
+        buffer_queue.add(new Bytes.take(data));
+        buffer_cond.signal();
+        buffer_mutex.unlock();
+    }
+
+    public void stop_dtls_connection() {
+        buffer_mutex.lock();
+        stop = true;
+        buffer_cond.signal();
+        buffer_mutex.unlock();
+    }
+
+    protected Bytes get_buffer_if_present () {
+        buffer_mutex.lock();
+        if (buffer_queue.size == 0) {
+            buffer_mutex.unlock();
+            return null;
+        }
+        Bytes res = buffer_queue.remove_at(0);
+        buffer_mutex.unlock();
+        return res;
+    }
+
+    public async Xmpp.Xep.Jingle.ContentEncryption? setup_dtls_connection() {
+        MainContext context = MainContext.current_source().get_context();
+        var thread = new Thread<Xmpp.Xep.Jingle.ContentEncryption>("dtls-connection", () => {
+            // Check we can start working on the thread
+            buffer_mutex.lock();
+            if (stop) {
+                restart = true;
+                buffer_mutex.unlock();
+                return null;
+            }
+            if (running || ready) {
+                buffer_mutex.unlock();
+                return null;
+            }
+            running = true;
+            restart = false;
+            buffer_mutex.unlock();
+
+            // Actual work
+            var res = setup_dtls_connection_thread();
+
+            // Callback
+            Source source = new IdleSource();
+            source.set_callback(setup_dtls_connection.callback);
+            source.attach(context);
+            return res;
+        });
+        yield;
+        return thread.join();
+    }
+
+    protected abstract Xmpp.Xep.Jingle.ContentEncryption? setup_dtls_connection_thread();
+}
+
+private string format_fingerprint(uint8[] fingerprint) {
+    var sb = new StringBuilder();
+    for (int i = 0; i < fingerprint.length; i++) {
+        sb.append("%02X".printf(fingerprint[i]));
+        if (i < fingerprint.length - 1) {
+            sb.append(":");
+        }
+    }
+    return sb.str;
+}
+
+
+public enum Mode {
+    CLIENT, SERVER
+}
+
+}