Improve & refactor Jingle base implementation

Co-authored-by: Marvin W <git@larma.de>

12 files changed, 1420 insertions, 0 deletions

diff --git a/xmpp-vala/src/module/xep/0166_jingle/component.vala b/xmpp-vala/src/module/xep/0166_jingle/component.vala
new file mode 100644
index 00000000..544bcd69
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/component.vala
@@ -0,0 +1,52 @@
+namespace Xmpp.Xep.Jingle {
+
+    public abstract class ComponentConnection : Object {
+        public uint8 component_id { get; set; default = 0; }
+        public abstract async void terminate(bool we_terminated, string? reason_name = null, string? reason_text = null);
+        public signal void connection_closed();
+        public signal void connection_error(IOError e);
+    }
+
+    public abstract class DatagramConnection : ComponentConnection {
+        public bool ready { get; set; default = false; }
+        private string? terminate_reason_name = null;
+        private string? terminate_reason_text = null;
+        private bool terminated = false;
+
+        public override async void terminate(bool we_terminated, string? reason_string = null, string? reason_text = null) {
+            if (!terminated) {
+                terminated = true;
+                terminate_reason_name = reason_string;
+                terminate_reason_text = reason_text;
+                connection_closed();
+            }
+        }
+
+        public signal void datagram_received(Bytes datagram);
+        public abstract void send_datagram(Bytes datagram);
+    }
+
+    public class StreamingConnection : ComponentConnection {
+        public Gee.Future<IOStream> stream { get { return promise.future; } }
+        protected Gee.Promise<IOStream> promise = new Gee.Promise<IOStream>();
+        private string? terminated = null;
+
+        public async void init(IOStream stream) {
+            assert(!this.stream.ready);
+            promise.set_value(stream);
+            if (terminated != null) {
+                yield stream.close_async();
+            }
+        }
+
+        public override async void terminate(bool we_terminated, string? reason_name = null, string? reason_text = null) {
+            if (terminated == null) {
+                terminated = (reason_name ?? "") + " - " + (reason_text ?? "") + @"we terminated? $we_terminated";
+                if (stream.ready) {
+                    yield stream.value.close_async();
+                }
+            }
+        }
+    }
+}
+
diff --git a/xmpp-vala/src/module/xep/0166_jingle/content.vala b/xmpp-vala/src/module/xep/0166_jingle/content.vala
new file mode 100644
index 00000000..67c13dd8
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/content.vala
@@ -0,0 +1,236 @@
+using Gee;
+using Xmpp;
+
+public class Xmpp.Xep.Jingle.Content : Object {
+
+    public signal void senders_modify_incoming(Senders proposed_senders);
+
+    // INITIATE_SENT -> CONNECTING -> [REPLACING_TRANSPORT -> CONNECTING ->]... ACTIVE -> ENDED
+    // INITIATE_RECEIVED -> CONNECTING -> [WAITING_FOR_TRANSPORT_REPLACE -> CONNECTING ->].. ACTIVE -> ENDED
+    public enum State {
+        PENDING,
+        WANTS_TO_BE_ACCEPTED,
+        ACCEPTED,
+        REPLACING_TRANSPORT,
+        WAITING_FOR_TRANSPORT_REPLACE
+    }
+
+    public State state { get; set; }
+
+    public Role role { get; private set; }
+    public Jid local_full_jid { get; private set; }
+    public Jid peer_full_jid { get; private set; }
+    public Role content_creator { get; private set; }
+    public string content_name { get; private set; }
+    public Senders senders { get; private set; }
+
+    public ContentType content_type;
+    public ContentParameters content_params;
+    public Transport transport;
+    public TransportParameters? transport_params;
+    public SecurityPrecondition security_precondition;
+    public SecurityParameters? security_params;
+
+    public weak Session session;
+    public Map<uint8, ComponentConnection> component_connections = new HashMap<uint8, ComponentConnection>(); // TODO private
+
+    // INITIATE_SENT | INITIATE_RECEIVED | CONNECTING
+    public Set<string> tried_transport_methods = new HashSet<string>();
+
+
+    public Content.initiate_sent(string content_name, Senders senders,
+                                 ContentType content_type, ContentParameters content_params,
+                                 Transport transport, TransportParameters? transport_params,
+                                 SecurityPrecondition? security_precondition, SecurityParameters? security_params,
+                                 Jid local_full_jid, Jid peer_full_jid) {
+        this.content_name = content_name;
+        this.senders = senders;
+        this.role = Role.INITIATOR;
+        this.local_full_jid = local_full_jid;
+        this.peer_full_jid = peer_full_jid;
+        this.content_creator = Role.INITIATOR;
+
+        this.content_type = content_type;
+        this.content_params = content_params;
+        this.transport = transport;
+        this.transport_params = transport_params;
+        this.security_precondition = security_precondition;
+        this.security_params = security_params;
+
+        this.tried_transport_methods.add(transport.ns_uri);
+
+        state = State.PENDING;
+    }
+
+    public Content.initiate_received(string content_name, Senders senders,
+                                     ContentType content_type, ContentParameters content_params,
+                                     Transport transport, TransportParameters? transport_params,
+                                     SecurityPrecondition? security_precondition, SecurityParameters? security_params,
+                                     Jid local_full_jid, Jid peer_full_jid) throws Error {
+        this.content_name = content_name;
+        this.senders = senders;
+        this.role = Role.RESPONDER;
+        this.local_full_jid = local_full_jid;
+        this.peer_full_jid = peer_full_jid;
+        this.content_creator = Role.INITIATOR;
+
+        this.content_type = content_type;
+        this.content_params = content_params;
+        this.transport = transport;
+        this.transport_params = transport_params;
+        this.security_precondition = security_precondition;
+        this.security_params = security_params;
+
+        if (transport != null) {
+            this.tried_transport_methods.add(transport.ns_uri);
+        }
+
+        state = State.PENDING;
+    }
+
+    public void set_session(Session session) {
+        this.session = session;
+        this.transport_params.set_content(this);
+    }
+
+    public void accept() {
+        state = State.WANTS_TO_BE_ACCEPTED;
+
+        session.accept_content(this);
+    }
+
+    public void reject() {
+        session.reject_content(this);
+    }
+
+    public void terminate(bool we_terminated, string? reason_name, string? reason_text) {
+        content_params.terminate(we_terminated, reason_name, reason_text);
+
+        foreach (ComponentConnection connection in component_connections.values) {
+            connection.terminate(we_terminated, reason_name, reason_text);
+        }
+    }
+
+    public void modify(Senders new_sender) {
+        session.send_content_modify(this, new_sender);
+        this.senders = new_sender;
+    }
+
+    public void accept_content_modify(Senders senders) {
+        this.senders = senders;
+    }
+
+    internal void handle_content_modify(XmppStream stream, Senders proposed_senders) {
+        senders_modify_incoming(proposed_senders);
+    }
+
+    internal void on_accept(XmppStream stream) {
+        this.transport_params.create_transport_connection(stream, this);
+        this.content_params.accept(stream, session, this);
+    }
+
+    internal void handle_accept(XmppStream stream, ContentNode content_node) {
+        this.transport_params.handle_transport_accept(content_node.transport);
+        this.transport_params.create_transport_connection(stream, this);
+        this.content_params.handle_accept(stream, this.session, this, content_node.description);
+    }
+
+    private async void select_new_transport() {
+        XmppStream stream = session.stream;
+        Transport? new_transport = yield stream.get_module(Module.IDENTITY).select_transport(stream, transport.type_, transport_params.components, peer_full_jid, tried_transport_methods);
+        if (new_transport == null) {
+            session.terminate(ReasonElement.FAILED_TRANSPORT, null, "failed transport");
+            // TODO should we only terminate this content or really the whole session?
+            return;
+        }
+        tried_transport_methods.add(new_transport.ns_uri);
+        transport_params = new_transport.create_transport_parameters(stream, transport_params.components, local_full_jid, peer_full_jid);
+        set_transport_params(transport_params);
+        session.send_transport_replace(this, transport_params);
+        state = State.REPLACING_TRANSPORT;
+    }
+
+    public void handle_transport_accept(XmppStream stream, StanzaNode transport_node, StanzaNode jingle, Iq.Stanza iq) throws IqError {
+        if (state != State.REPLACING_TRANSPORT) {
+            throw new IqError.OUT_OF_ORDER("no outstanding transport-replace request");
+        }
+        if (transport_node.ns_uri != transport.ns_uri) {
+            throw new IqError.BAD_REQUEST("transport-accept with unnegotiated transport method");
+        }
+        transport_params.handle_transport_accept(transport_node);
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
+        transport_params.create_transport_connection(stream, this);
+    }
+
+    public void handle_transport_reject(XmppStream stream, StanzaNode jingle, Iq.Stanza iq) throws IqError {
+        if (state != State.REPLACING_TRANSPORT) {
+            throw new IqError.OUT_OF_ORDER("no outstanding transport-replace request");
+        }
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
+        select_new_transport.begin();
+    }
+
+    public void handle_transport_replace(XmppStream stream, StanzaNode transport_node, StanzaNode jingle, Iq.Stanza iq) throws IqError {
+        Transport? transport = stream.get_module(Module.IDENTITY).get_transport(transport_node.ns_uri);
+        TransportParameters? parameters = null;
+        if (transport != null) {
+            // Just parse the transport info for the errors.
+            parameters = transport.parse_transport_parameters(stream, content_type.required_components, local_full_jid, peer_full_jid, transport_node);
+        }
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
+        if (state != State.WAITING_FOR_TRANSPORT_REPLACE || transport == null) {
+            session.send_transport_reject(this, transport_node);
+            return;
+        }
+        set_transport_params(parameters);
+        session.send_transport_accept(this, parameters);
+
+        this.transport_params.create_transport_connection(stream, this);
+    }
+
+    public void handle_transport_info(XmppStream stream, StanzaNode transport, StanzaNode jingle, Iq.Stanza iq) throws IqError {
+        this.transport_params.handle_transport_info(transport);
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
+    }
+
+    public void on_description_info(XmppStream stream, StanzaNode description, StanzaNode jinglq, Iq.Stanza iq) throws IqError {
+        // TODO: do something.
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
+    }
+
+    void verify_content(ContentNode content) throws IqError {
+        if (content.name != content_name || content.creator != content_creator) {
+            throw new IqError.BAD_REQUEST("unknown content");
+        }
+    }
+
+    public void set_transport_connection(ComponentConnection? conn, uint8 component = 1) {
+        debug(@"set_transport_connection: %s, %s, %i, %s, overwrites: %s", this.content_name, this.state.to_string(), component, (conn != null).to_string(), component_connections.has_key(component).to_string());
+
+        if (conn != null) {
+            component_connections[component] = conn;
+            if (transport_params.components == component) {
+                state = State.ACCEPTED;
+                tried_transport_methods.clear();
+            }
+        } else {
+            if (role == Role.INITIATOR) {
+                select_new_transport.begin();
+            } else {
+                state = State.WAITING_FOR_TRANSPORT_REPLACE;
+            }
+        }
+    }
+
+    private void set_transport_params(TransportParameters transport_params) {
+        this.transport_params = transport_params;
+    }
+
+    public ComponentConnection? get_transport_connection(uint8 component = 1) {
+        return component_connections[component];
+    }
+
+    public void send_transport_info(StanzaNode transport) {
+        session.send_transport_info(this, transport);
+    }
+}
\ No newline at end of file
diff --git a/xmpp-vala/src/module/xep/0166_jingle/content_description.vala b/xmpp-vala/src/module/xep/0166_jingle/content_description.vala
new file mode 100644
index 00000000..1a24e52e
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/content_description.vala
@@ -0,0 +1,27 @@
+using Gee;
+using Xmpp.Xep;
+using Xmpp;
+
+namespace Xmpp.Xep.Jingle {
+
+    public interface ContentType : Object {
+        public abstract string ns_uri { get; }
+        public abstract TransportType required_transport_type { get; }
+        public abstract uint8 required_components { get; }
+        public abstract ContentParameters parse_content_parameters(StanzaNode description) throws IqError;
+    }
+
+    public interface ContentParameters : Object {
+        /** Called when the counterpart proposes the content */
+        public abstract async void handle_proposed_content(XmppStream stream, Jingle.Session session, Content content);
+
+        /** Called when we accept the content that was proposed by the counterpart */
+        public abstract void accept(XmppStream stream, Jingle.Session session, Jingle.Content content);
+        /** Called when the counterpart accepts the content that was proposed by us*/
+        public abstract void handle_accept(XmppStream stream, Jingle.Session session, Jingle.Content content, StanzaNode description_node);
+
+        public abstract void terminate(bool we_terminated, string? reason_name, string? reason_text);
+
+        public abstract StanzaNode get_description_node();
+    }
+}
\ No newline at end of file
diff --git a/xmpp-vala/src/module/xep/0166_jingle/content_node.vala b/xmpp-vala/src/module/xep/0166_jingle/content_node.vala
new file mode 100644
index 00000000..7d8d56c8
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/content_node.vala
@@ -0,0 +1,112 @@
+using Gee;
+using Xmpp.Xep;
+using Xmpp;
+
+namespace Xmpp.Xep.Jingle {
+
+    class ContentNode {
+        public Role creator;
+        public string name;
+        public Senders senders;
+        public StanzaNode? description;
+        public StanzaNode? transport;
+        public StanzaNode? security;
+    }
+
+    [Version(deprecated = true)]
+    ContentNode get_single_content_node(StanzaNode jingle) throws IqError {
+        Gee.List<StanzaNode> contents = jingle.get_subnodes("content");
+        if (contents.size == 0) {
+            throw new IqError.BAD_REQUEST("missing content node");
+        }
+        if (contents.size > 1) {
+            throw new IqError.NOT_IMPLEMENTED("can't process multiple content nodes");
+        }
+        StanzaNode content = contents[0];
+        string? creator_str = content.get_attribute("creator");
+        // Vala can't typecheck the ternary operator here.
+        Role? creator = null;
+        if (creator_str != null) {
+            creator = Role.parse(creator_str);
+        } else {
+            // TODO(hrxi): now, is the creator attribute optional or not (XEP-0166
+            // Jingle)?
+            creator = Role.INITIATOR;
+        }
+
+        string? name = content.get_attribute("name");
+
+        Senders senders = Senders.parse(content.get_attribute("senders"));
+
+        StanzaNode? description = get_single_node_anyns(content, "description");
+        StanzaNode? transport = get_single_node_anyns(content, "transport");
+        StanzaNode? security = get_single_node_anyns(content, "security");
+        if (name == null || creator == null) {
+            throw new IqError.BAD_REQUEST("missing name or creator");
+        }
+
+        return new ContentNode() {
+            creator=creator,
+            name=name,
+            senders=senders,
+            description=description,
+            transport=transport,
+            security=security
+        };
+    }
+
+    Gee.List<ContentNode> get_content_nodes(StanzaNode jingle) throws IqError {
+        Gee.List<StanzaNode> contents = jingle.get_subnodes("content");
+        if (contents.size == 0) {
+            throw new IqError.BAD_REQUEST("missing content node");
+        }
+        Gee.List<ContentNode> list = new ArrayList<ContentNode>();
+        foreach (StanzaNode content in contents) {
+            string? creator_str = content.get_attribute("creator");
+            // Vala can't typecheck the ternary operator here.
+            Role? creator = null;
+            if (creator_str != null) {
+                creator = Role.parse(creator_str);
+            } else {
+                // TODO(hrxi): now, is the creator attribute optional or not (XEP-0166
+                // Jingle)?
+                creator = Role.INITIATOR;
+            }
+
+            string? name = content.get_attribute("name");
+            Senders senders = Senders.parse(content.get_attribute("senders"));
+            StanzaNode? description = get_single_node_anyns(content, "description");
+            StanzaNode? transport = get_single_node_anyns(content, "transport");
+            StanzaNode? security = get_single_node_anyns(content, "security");
+            if (name == null || creator == null) {
+                throw new IqError.BAD_REQUEST("missing name or creator");
+            }
+            list.add(new ContentNode() {
+                creator=creator,
+                name=name,
+                senders=senders,
+                description=description,
+                transport=transport,
+                security=security
+            });
+        }
+        return list;
+    }
+
+    StanzaNode? get_single_node_anyns(StanzaNode parent, string? node_name = null) throws IqError {
+        StanzaNode? result = null;
+        foreach (StanzaNode child in parent.get_all_subnodes()) {
+            if (node_name == null || child.name == node_name) {
+                if (result != null) {
+                    if (node_name != null) {
+                        throw new IqError.BAD_REQUEST(@"multiple $(node_name) nodes");
+                    } else {
+                        throw new IqError.BAD_REQUEST(@"expected single subnode");
+                    }
+                }
+                result = child;
+            }
+        }
+        return result;
+    }
+}
\ No newline at end of file
diff --git a/xmpp-vala/src/module/xep/0166_jingle/content_security.vala b/xmpp-vala/src/module/xep/0166_jingle/content_security.vala
new file mode 100644
index 00000000..0e10311d
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/content_security.vala
@@ -0,0 +1,18 @@
+using Gee;
+using Xmpp.Xep;
+using Xmpp;
+
+namespace Xmpp.Xep.Jingle {
+
+    public interface SecurityPrecondition : Object {
+        public abstract string security_ns_uri();
+        public abstract SecurityParameters? create_security_parameters(XmppStream stream, Jid local_full_jid, Jid peer_full_jid, Object options) throws Jingle.Error;
+        public abstract SecurityParameters? parse_security_parameters(XmppStream stream, Jid local_full_jid, Jid peer_full_jid, StanzaNode security) throws IqError;
+    }
+
+    public interface SecurityParameters : Object {
+        public abstract string security_ns_uri();
+        public abstract StanzaNode to_security_stanza_node(XmppStream stream, Jid local_full_jid, Jid peer_full_jid);
+        public abstract IOStream wrap_stream(IOStream stream);
+    }
+}
\ No newline at end of file
diff --git a/xmpp-vala/src/module/xep/0166_jingle/content_transport.vala b/xmpp-vala/src/module/xep/0166_jingle/content_transport.vala
new file mode 100644
index 00000000..cd74c836
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/content_transport.vala
@@ -0,0 +1,29 @@
+namespace Xmpp.Xep.Jingle {
+
+    public interface Transport : Object {
+        public abstract string ns_uri { get; }
+        public async abstract bool is_transport_available(XmppStream stream, uint8 components, Jid full_jid);
+        public abstract TransportType type_ { get; }
+        public abstract int priority { get; }
+        public abstract TransportParameters create_transport_parameters(XmppStream stream, uint8 components, Jid local_full_jid, Jid peer_full_jid) throws Error;
+        public abstract TransportParameters parse_transport_parameters(XmppStream stream, uint8 components, Jid local_full_jid, Jid peer_full_jid, StanzaNode transport) throws IqError;
+    }
+
+    public enum TransportType {
+        DATAGRAM,
+        STREAMING,
+    }
+
+    // Gets a null `stream` if connection setup was unsuccessful and another
+    // transport method should be tried.
+    public interface TransportParameters : Object {
+        public abstract string ns_uri { get; }
+        public abstract uint8 components { get; }
+
+        public abstract void set_content(Content content);
+        public abstract StanzaNode to_transport_stanza_node();
+        public abstract void handle_transport_accept(StanzaNode transport) throws IqError;
+        public abstract void handle_transport_info(StanzaNode transport) throws IqError;
+        public abstract void create_transport_connection(XmppStream stream, Content content);
+    }
+}
\ No newline at end of file
diff --git a/xmpp-vala/src/module/xep/0166_jingle/jingle_flag.vala b/xmpp-vala/src/module/xep/0166_jingle/jingle_flag.vala
new file mode 100644
index 00000000..9f0acd27
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/jingle_flag.vala
@@ -0,0 +1,38 @@
+using Gee;
+using Xmpp;
+
+public class Xmpp.Xep.Jingle.Flag : XmppStreamFlag {
+    public static FlagIdentity<Flag> IDENTITY = new FlagIdentity<Flag>(NS_URI, "jingle");
+
+    public HashMap<string, Session> sessions = new HashMap<string, Session>();
+    public HashMap<string, Promise<Session?>> promises = new HashMap<string, Promise<Session?>>();
+
+    // We might get transport-infos about a session before we finished fully creating the session. (e.g. telepathy outgoing calls)
+    // Thus, we "pre add" the session as soon as possible and can then await it.
+    public void pre_add_session(string sid) {
+        var promise = new Promise<Session?>();
+        promises[sid] = promise;
+    }
+
+    public void add_session(Session session) {
+        if (promises.has_key(session.sid)) {
+            promises[session.sid].set_value(session);
+            promises.unset(session.sid);
+        }
+        sessions[session.sid] = session;
+    }
+
+    public async Session? get_session(string sid) {
+        if (promises.has_key(sid)) {
+            return yield promises[sid].future.wait_async();
+        }
+        return sessions[sid];
+    }
+
+    public void remove_session(string sid) {
+        sessions.unset(sid);
+    }
+
+    public override string get_ns() { return NS_URI; }
+    public override string get_id() { return IDENTITY.id; }
+}
\ No newline at end of file
diff --git a/xmpp-vala/src/module/xep/0166_jingle/jingle_module.vala b/xmpp-vala/src/module/xep/0166_jingle/jingle_module.vala
new file mode 100644
index 00000000..1e8a36d1
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/jingle_module.vala
@@ -0,0 +1,235 @@
+using Gee;
+using Xmpp;
+
+namespace Xmpp.Xep.Jingle {
+
+    internal const string NS_URI = "urn:xmpp:jingle:1";
+    private const string ERROR_NS_URI = "urn:xmpp:jingle:errors:1";
+
+    // This module can only be attached to one stream at a time.
+    public class Module : XmppStreamModule, Iq.Handler {
+        public static Xmpp.ModuleIdentity<Module> IDENTITY = new Xmpp.ModuleIdentity<Module>(NS_URI, "0166_jingle");
+
+        public signal void session_initiate_received(XmppStream stream, Session session);
+
+        private HashMap<string, ContentType> content_types = new HashMap<string, ContentType>();
+        private HashMap<string, SessionInfoNs> session_info_types = new HashMap<string, SessionInfoNs>();
+        private HashMap<string, Transport> transports = new HashMap<string, Transport>();
+        private HashMap<string, SecurityPrecondition> security_preconditions = new HashMap<string, SecurityPrecondition>();
+
+        public override void attach(XmppStream stream) {
+            stream.add_flag(new Flag());
+            stream.get_module(ServiceDiscovery.Module.IDENTITY).add_feature(stream, NS_URI);
+            stream.get_module(Iq.Module.IDENTITY).register_for_namespace(NS_URI, this);
+
+            // TODO update stream in all sessions
+        }
+
+        public override void detach(XmppStream stream) {
+            stream.get_module(ServiceDiscovery.Module.IDENTITY).remove_feature(stream, NS_URI);
+            stream.get_module(Iq.Module.IDENTITY).unregister_from_namespace(NS_URI, this);
+        }
+
+        public void register_content_type(ContentType content_type) {
+            content_types[content_type.ns_uri] = content_type;
+        }
+
+        public void register_session_info_type(SessionInfoNs info_ns) {
+            session_info_types[info_ns.ns_uri] = info_ns;
+        }
+
+        public ContentType? get_content_type(string ns_uri) {
+            if (!content_types.has_key(ns_uri)) {
+                return null;
+            }
+            return content_types[ns_uri];
+        }
+
+        public SessionInfoNs? get_session_info_type(string ns_uri) {
+            return session_info_types[ns_uri];
+        }
+
+        public void register_transport(Transport transport) {
+            transports[transport.ns_uri] = transport;
+        }
+
+        public Transport? get_transport(string ns_uri) {
+            if (!transports.has_key(ns_uri)) {
+                return null;
+            }
+            return transports[ns_uri];
+        }
+
+        public async Transport? select_transport(XmppStream stream, TransportType type, uint8 components, Jid receiver_full_jid, Set<string> blacklist) {
+            Transport? result = null;
+            foreach (Transport transport in transports.values) {
+                if (transport.type_ != type) {
+                    continue;
+                }
+                if (transport.ns_uri in blacklist) {
+                    continue;
+                }
+                if (yield transport.is_transport_available(stream, components, receiver_full_jid)) {
+                    if (result != null) {
+                        if (result.priority >= transport.priority) {
+                            continue;
+                        }
+                    }
+                    result = transport;
+                }
+            }
+            return result;
+        }
+
+        public void register_security_precondition(SecurityPrecondition precondition) {
+            security_preconditions[precondition.security_ns_uri()] = precondition;
+        }
+
+        public SecurityPrecondition? get_security_precondition(string? ns_uri) {
+            if (ns_uri == null) return null;
+            if (!security_preconditions.has_key(ns_uri)) {
+                return null;
+            }
+            return security_preconditions[ns_uri];
+        }
+
+        private async bool is_jingle_available(XmppStream stream, Jid full_jid) {
+            bool? has_jingle = yield stream.get_module(ServiceDiscovery.Module.IDENTITY).has_entity_feature(stream, full_jid, NS_URI);
+            return has_jingle != null && has_jingle;
+        }
+
+        public async bool is_available(XmppStream stream, TransportType type, uint8 components, Jid full_jid) {
+            return (yield is_jingle_available(stream, full_jid)) && (yield select_transport(stream, type, components, full_jid, Set.empty())) != null;
+        }
+
+        public async Session create_session(XmppStream stream, Gee.List<Content> contents, Jid receiver_full_jid, string sid = random_uuid()) throws Error {
+            if (!yield is_jingle_available(stream, receiver_full_jid)) {
+                throw new Error.NO_SHARED_PROTOCOLS("No Jingle support");
+            }
+            Jid? my_jid = stream.get_flag(Bind.Flag.IDENTITY).my_jid;
+            if (my_jid == null) {
+                throw new Error.GENERAL("Couldn't determine own JID");
+            }
+
+            Session session = new Session.initiate_sent(stream, sid, my_jid, receiver_full_jid);
+            session.terminated.connect((session, stream, _1, _2, _3) => { stream.get_flag(Flag.IDENTITY).remove_session(session.sid); });
+
+            foreach (Content content in contents) {
+                session.insert_content(content);
+            }
+
+            // Build & send session-initiate iq stanza
+            StanzaNode initiate_jingle_iq = new StanzaNode.build("jingle", NS_URI)
+                    .add_self_xmlns()
+                    .put_attribute("action", "session-initiate")
+                    .put_attribute("initiator", my_jid.to_string())
+                    .put_attribute("sid", session.sid);
+
+            foreach (Content content in contents) {
+                StanzaNode content_node = new StanzaNode.build("content", NS_URI)
+                        .put_attribute("creator", "initiator")
+                        .put_attribute("name", content.content_name)
+                        .put_attribute("senders", content.senders.to_string())
+                        .put_node(content.content_params.get_description_node())
+                        .put_node(content.transport_params.to_transport_stanza_node());
+                if (content.security_params != null) {
+                    content_node.put_node(content.security_params.to_security_stanza_node(stream, my_jid, receiver_full_jid));
+                }
+                initiate_jingle_iq.put_node(content_node);
+            }
+
+            Iq.Stanza iq = new Iq.Stanza.set(initiate_jingle_iq) { to=receiver_full_jid };
+
+            stream.get_flag(Flag.IDENTITY).add_session(session);
+            // We might get a follow-up before the ack => add_session before send_iq returns
+            stream.get_module(Iq.Module.IDENTITY).send_iq(stream, iq, (stream, iq) => {
+                if (iq.is_error()) warning("Jingle session-initiate got error: %s", iq.stanza.to_string());
+            });
+
+            return session;
+        }
+
+        public async void handle_session_initiate(XmppStream stream, string sid, StanzaNode jingle, Iq.Stanza iq) throws IqError {
+            Jid? my_jid = stream.get_flag(Bind.Flag.IDENTITY).my_jid;
+            if (my_jid == null) {
+                throw new IqError.RESOURCE_CONSTRAINT("Couldn't determine own JID");
+            }
+
+            Session session = new Session.initiate_received(stream, sid, my_jid, iq.from);
+            session.terminated.connect((stream) => { stream.get_flag(Flag.IDENTITY).remove_session(sid); });
+
+            stream.get_flag(Flag.IDENTITY).pre_add_session(session.sid);
+
+            foreach (ContentNode content_node in get_content_nodes(jingle)) {
+                yield session.insert_content_node(content_node, iq.from);
+            }
+
+            stream.get_flag(Flag.IDENTITY).add_session(session);
+
+            stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
+
+            session_initiate_received(stream, session);
+        }
+
+        public async void on_iq_set(XmppStream stream, Iq.Stanza iq) {
+            try {
+                yield handle_iq_set(stream, iq);
+            } catch (IqError e) {
+                send_iq_error(e, stream, iq);
+            }
+        }
+
+        public async void handle_iq_set(XmppStream stream, Iq.Stanza iq) throws IqError {
+            StanzaNode? jingle_node = iq.stanza.get_subnode("jingle", NS_URI);
+            if (jingle_node == null) {
+                throw new IqError.BAD_REQUEST("missing jingle node");
+            }
+            string? sid = jingle_node.get_attribute("sid");
+            string? action = jingle_node.get_attribute("action");
+            if (sid == null || action == null) {
+                throw new IqError.BAD_REQUEST("missing jingle node, sid or action");
+            }
+
+            Session? session = yield stream.get_flag(Flag.IDENTITY).get_session(sid);
+            if (action == "session-initiate") {
+                if (session != null) {
+                    stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.error(iq, new ErrorStanza.build(ErrorStanza.TYPE_MODIFY, ErrorStanza.CONDITION_CONFLICT, "session ID already in use", null)) { to=iq.from });
+                    return;
+                }
+                yield handle_session_initiate(stream, sid, jingle_node, iq);
+                return;
+            }
+            if (session == null) {
+                StanzaNode unknown_session = new StanzaNode.build("unknown-session", ERROR_NS_URI).add_self_xmlns();
+                stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.error(iq, new ErrorStanza.item_not_found(unknown_session)) { to=iq.from });
+                return;
+            }
+            session.handle_iq_set(action, jingle_node, iq);
+        }
+
+        public override string get_ns() { return NS_URI; }
+        public override string get_id() { return IDENTITY.id; }
+    }
+
+    void send_iq_error(IqError iq_error, XmppStream stream, Iq.Stanza iq) {
+        ErrorStanza error;
+        if (iq_error is IqError.BAD_REQUEST) {
+            error = new ErrorStanza.bad_request(iq_error.message);
+        } else if (iq_error is IqError.NOT_ACCEPTABLE) {
+            error = new ErrorStanza.not_acceptable(iq_error.message);
+        } else if (iq_error is IqError.NOT_IMPLEMENTED) {
+            error = new ErrorStanza.feature_not_implemented(iq_error.message);
+        } else if (iq_error is IqError.UNSUPPORTED_INFO) {
+            StanzaNode unsupported_info = new StanzaNode.build("unsupported-info", ERROR_NS_URI).add_self_xmlns();
+            error = new ErrorStanza.build(ErrorStanza.TYPE_CANCEL, ErrorStanza.CONDITION_FEATURE_NOT_IMPLEMENTED, iq_error.message, unsupported_info);
+        } else if (iq_error is IqError.OUT_OF_ORDER) {
+            StanzaNode out_of_order = new StanzaNode.build("out-of-order", ERROR_NS_URI).add_self_xmlns();
+            error = new ErrorStanza.build(ErrorStanza.TYPE_MODIFY, ErrorStanza.CONDITION_UNEXPECTED_REQUEST, iq_error.message, out_of_order);
+        } else if (iq_error is IqError.RESOURCE_CONSTRAINT) {
+            error = new ErrorStanza.resource_constraint(iq_error.message);
+        } else {
+            assert_not_reached();
+        }
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.error(iq, error) { to=iq.from });
+    }
+}
\ No newline at end of file
diff --git a/xmpp-vala/src/module/xep/0166_jingle/jingle_structs.vala b/xmpp-vala/src/module/xep/0166_jingle/jingle_structs.vala
new file mode 100644
index 00000000..0f283e0e
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/jingle_structs.vala
@@ -0,0 +1,73 @@
+using Gee;
+using Xmpp;
+
+namespace Xmpp.Xep.Jingle {
+
+    public errordomain IqError {
+        BAD_REQUEST,
+        NOT_ACCEPTABLE,
+        NOT_IMPLEMENTED,
+        UNSUPPORTED_INFO,
+        OUT_OF_ORDER,
+        RESOURCE_CONSTRAINT,
+    }
+
+    public errordomain Error {
+        GENERAL,
+        BAD_REQUEST,
+        INVALID_PARAMETERS,
+        UNSUPPORTED_TRANSPORT,
+        UNSUPPORTED_SECURITY,
+        NO_SHARED_PROTOCOLS,
+        TRANSPORT_ERROR,
+    }
+
+    public enum Senders {
+        BOTH,
+        INITIATOR,
+        NONE,
+        RESPONDER;
+
+        public string to_string() {
+            switch (this) {
+                case BOTH: return "both";
+                case INITIATOR: return "initiator";
+                case NONE: return "none";
+                case RESPONDER: return "responder";
+            }
+            assert_not_reached();
+        }
+
+        public static Senders parse(string? senders) throws IqError {
+            if (senders == null) return Senders.BOTH;
+            switch (senders) {
+                case "initiator": return Senders.INITIATOR;
+                case "responder": return Senders.RESPONDER;
+                case "both": return Senders.BOTH;
+            }
+            throw new IqError.BAD_REQUEST(@"invalid role $(senders)");
+        }
+    }
+
+    public enum Role {
+        INITIATOR,
+        RESPONDER;
+
+        public string to_string() {
+            switch (this) {
+                case INITIATOR: return "initiator";
+                case RESPONDER: return "responder";
+            }
+            assert_not_reached();
+        }
+
+        public static Role parse(string role) throws IqError {
+            switch (role) {
+                case "initiator": return INITIATOR;
+                case "responder": return RESPONDER;
+            }
+            throw new IqError.BAD_REQUEST(@"invalid role $(role)");
+        }
+    }
+
+}
\ No newline at end of file
diff --git a/xmpp-vala/src/module/xep/0166_jingle/reason_element.vala b/xmpp-vala/src/module/xep/0166_jingle/reason_element.vala
new file mode 100644
index 00000000..1cbdf936
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/reason_element.vala
@@ -0,0 +1,29 @@
+using Gee;
+using Xmpp;
+
+namespace  Xmpp.Xep.Jingle.ReasonElement {
+    public const string ALTERNATIVE_SESSION = "alternative-session";
+    public const string BUSY = "busy";
+    public const string CANCEL = "cancel";
+    public const string CONNECTIVITY_ERROR = "connectivity-error";
+    public const string DECLINE = "decline";
+    public const string EXPIRED = "expired";
+    public const string FAILED_APPLICATION = "failed_application";
+    public const string FAILED_TRANSPORT = "failed_transport";
+    public const string GENERAL_ERROR = "general-error";
+    public const string GONE = "gone";
+    public const string INCOMPATIBLE_PARAMETERS = "incompatible-parameters";
+    public const string MEDIA_ERROR = "media-error";
+    public const string SECURITY_ERROR = "security-error";
+    public const string SUCCESS = "success";
+    public const string TIMEOUT = "timeout";
+    public const string UNSUPPORTED_APPLICATIONS = "unsupported-applications";
+    public const string UNSUPPORTED_TRANSPORTS = "unsupported-transports";
+
+    public const string[] NORMAL_TERMINATE_REASONS = {
+        BUSY,
+        CANCEL,
+        DECLINE,
+        SUCCESS
+    };
+}
\ No newline at end of file
diff --git a/xmpp-vala/src/module/xep/0166_jingle/session.vala b/xmpp-vala/src/module/xep/0166_jingle/session.vala
new file mode 100644
index 00000000..e9ad9169
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/session.vala
@@ -0,0 +1,559 @@
+using Gee;
+using Xmpp;
+
+
+public delegate void Xmpp.Xep.Jingle.SessionTerminate(Jid to, string sid, StanzaNode reason);
+
+public class Xmpp.Xep.Jingle.Session : Object {
+
+    public signal void terminated(XmppStream stream, bool we_terminated, string? reason_name, string? reason_text);
+    public signal void additional_content_add_incoming(XmppStream stream, Content content);
+
+    // INITIATE_SENT/INITIATE_RECEIVED -> CONNECTING -> PENDING -> ACTIVE -> ENDED
+    public enum State {
+        INITIATE_SENT,
+        INITIATE_RECEIVED,
+        ACTIVE,
+        ENDED,
+    }
+
+    public XmppStream stream { get; set; }
+    public State state { get; set; }
+    public string sid { get; private set; }
+    public Jid local_full_jid { get; private set; }
+    public Jid peer_full_jid { get; private set; }
+    public bool we_initiated { get; private set; }
+
+    public HashMap<string, Content> contents = new HashMap<string, Content>();
+
+    public SecurityParameters? security { get { return contents.values.to_array()[0].security_params; } }
+
+    public Session.initiate_sent(XmppStream stream, string sid, Jid local_full_jid, Jid peer_full_jid) {
+        this.stream = stream;
+        this.sid = sid;
+        this.local_full_jid = local_full_jid;
+        this.peer_full_jid = peer_full_jid;
+        this.state = State.INITIATE_SENT;
+        this.we_initiated = true;
+    }
+
+    public Session.initiate_received(XmppStream stream, string sid, Jid local_full_jid, Jid peer_full_jid) {
+        this.stream = stream;
+        this.sid = sid;
+        this.local_full_jid = local_full_jid;
+        this.peer_full_jid = peer_full_jid;
+        this.state = State.INITIATE_RECEIVED;
+        this.we_initiated = false;
+    }
+
+    public void handle_iq_set(string action, StanzaNode jingle, Iq.Stanza iq) throws IqError {
+
+        if (action.has_prefix("session-")) {
+            switch (action) {
+                case "session-accept":
+                    Gee.List<ContentNode> content_nodes = get_content_nodes(jingle);
+
+                    if (state != State.INITIATE_SENT) {
+                        throw new IqError.OUT_OF_ORDER("got session-accept while not waiting for one");
+                    }
+                    handle_session_accept(content_nodes, jingle, iq);
+                    break;
+                case "session-info":
+                    handle_session_info.begin(jingle, iq);
+                    break;
+                case "session-terminate":
+                    handle_session_terminate(jingle, iq);
+                    break;
+                default:
+                    throw new IqError.BAD_REQUEST("invalid action");
+            }
+
+
+        } else if (action.has_prefix("content-")) {
+            switch (action) {
+                case "content-accept":
+                    ContentNode content_node = get_single_content_node(jingle);
+                    handle_content_accept(content_node);
+                    stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
+                    break;
+                case "content-add":
+                    ContentNode content_node = get_single_content_node(jingle);
+                    insert_content_node.begin(content_node, peer_full_jid);
+                    stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
+                    break;
+                case "content-modify":
+                    handle_content_modify(stream, jingle, iq);
+                    break;
+                case "content-reject":
+                case "content-remove":
+                    throw new IqError.NOT_IMPLEMENTED(@"$(action) is not implemented");
+                default:
+                    throw new IqError.BAD_REQUEST("invalid action");
+            }
+
+
+        } else if (action.has_prefix("transport-")) {
+            ContentNode content_node = get_single_content_node(jingle);
+            if (!contents.has_key(content_node.name)) {
+                throw new IqError.BAD_REQUEST("unknown content");
+            }
+
+            if (content_node.transport == null) {
+                throw new IqError.BAD_REQUEST("missing transport node");
+            }
+
+            Content content = contents[content_node.name];
+
+            if (content_node.creator != content.content_creator) {
+                throw new IqError.BAD_REQUEST("unknown content; creator");
+            }
+
+            switch (action) {
+                case "transport-accept":
+                    content.handle_transport_accept(stream, content_node.transport, jingle, iq);
+                    break;
+                case "transport-info":
+                    content.handle_transport_info(stream, content_node.transport, jingle, iq);
+                    break;
+                case "transport-reject":
+                    content.handle_transport_reject(stream, jingle, iq);
+                    break;
+                case "transport-replace":
+                    content.handle_transport_replace(stream, content_node.transport, jingle, iq);
+                    break;
+                default:
+                    throw new IqError.BAD_REQUEST("invalid action");
+            }
+
+
+        } else if (action == "description-info") {
+            ContentNode content_node = get_single_content_node(jingle);
+            if (!contents.has_key(content_node.name)) {
+                throw new IqError.BAD_REQUEST("unknown content");
+            }
+
+            Content content = contents[content_node.name];
+
+            if (content_node.creator != content.content_creator) {
+                throw new IqError.BAD_REQUEST("unknown content; creator");
+            }
+
+            content.on_description_info(stream, content_node.description, jingle, iq);
+        } else if (action == "security-info") {
+            throw new IqError.NOT_IMPLEMENTED(@"$(action) is not implemented");
+
+
+        } else {
+            throw new IqError.BAD_REQUEST("invalid action");
+        }
+    }
+
+    internal void insert_content(Content content) {
+        this.contents[content.content_name] = content;
+        content.set_session(this);
+    }
+
+    internal async void insert_content_node(ContentNode content_node, Jid peer_full_jid) throws IqError {
+        if (content_node.description == null || content_node.transport == null) {
+            throw new IqError.BAD_REQUEST("missing description or transport node");
+        }
+
+        Jid? my_jid = stream.get_flag(Bind.Flag.IDENTITY).my_jid;
+
+        Transport? transport = stream.get_module(Jingle.Module.IDENTITY).get_transport(content_node.transport.ns_uri);
+        ContentType? content_type = stream.get_module(Jingle.Module.IDENTITY).get_content_type(content_node.description.ns_uri);
+
+        if (content_type == null) {
+            // TODO(hrxi): how do we signal an unknown content type?
+            throw new IqError.NOT_IMPLEMENTED("unknown content type");
+        }
+
+        TransportParameters? transport_params = null;
+        if (transport != null) {
+            transport_params = transport.parse_transport_parameters(stream, content_type.required_components, my_jid, peer_full_jid, content_node.transport);
+        } else {
+            // terminate the session below
+        }
+
+        ContentParameters content_params = content_type.parse_content_parameters(content_node.description);
+
+        SecurityPrecondition? precondition = content_node.security != null ? stream.get_module(Jingle.Module.IDENTITY).get_security_precondition(content_node.security.ns_uri) : null;
+        SecurityParameters? security_params = null;
+        if (precondition != null) {
+            debug("Using precondition %s", precondition.security_ns_uri());
+            security_params = precondition.parse_security_parameters(stream, my_jid, peer_full_jid, content_node.security);
+        } else if (content_node.security != null) {
+            throw new IqError.NOT_IMPLEMENTED("unknown security precondition");
+        }
+
+        TransportType type = content_type.required_transport_type;
+
+        if (transport == null || transport.type_ != type) {
+            terminate(ReasonElement.UNSUPPORTED_TRANSPORTS, null, "unsupported transports");
+            throw new IqError.NOT_IMPLEMENTED("unsupported transports");
+        }
+
+        Content content = new Content.initiate_received(content_node.name, content_node.senders,
+                content_type, content_params,
+                transport, transport_params,
+                precondition, security_params,
+                my_jid, peer_full_jid);
+        insert_content(content);
+
+        yield content_params.handle_proposed_content(stream, this, content);
+
+        if (this.state == State.ACTIVE) {
+            additional_content_add_incoming(stream, content);
+        }
+    }
+
+    public async void add_content(Content content) {
+        content.session = this;
+        this.contents[content.content_name] = content;
+
+        StanzaNode content_add_node = new StanzaNode.build("jingle", NS_URI)
+                .add_self_xmlns()
+                .put_attribute("action", "content-add")
+                .put_attribute("sid", sid)
+                .put_node(new StanzaNode.build("content", NS_URI)
+                    .put_attribute("creator", "initiator")
+                    .put_attribute("name", content.content_name)
+                    .put_attribute("senders", content.senders.to_string())
+                    .put_node(content.content_params.get_description_node())
+                    .put_node(content.transport_params.to_transport_stanza_node()));
+
+        Iq.Stanza iq = new Iq.Stanza.set(content_add_node) { to=peer_full_jid };
+        yield stream.get_module(Iq.Module.IDENTITY).send_iq_async(stream, iq);
+    }
+
+    private void handle_content_accept(ContentNode content_node) throws IqError {
+        if (content_node.description == null || content_node.transport == null) throw new IqError.BAD_REQUEST("missing description or transport node");
+        if (!contents.has_key(content_node.name)) throw new IqError.BAD_REQUEST("unknown content");
+
+        Content content = contents[content_node.name];
+
+        if (content_node.creator != content.content_creator) warning("Counterpart accepts content with an unexpected `creator`");
+        if (content_node.senders != content.senders) warning("Counterpart accepts content with an unexpected `senders`");
+        if (content_node.transport.ns_uri != content.transport_params.ns_uri) throw new IqError.BAD_REQUEST("session-accept with unnegotiated transport method");
+
+        content.handle_accept(stream, content_node);
+    }
+
+    private void handle_content_modify(XmppStream stream, StanzaNode jingle_node, Iq.Stanza iq) throws IqError {
+        ContentNode content_node = get_single_content_node(jingle_node);
+
+        Content? content = contents[content_node.name];
+
+        if (content == null) throw new IqError.BAD_REQUEST("no such content");
+        if (content_node.creator != content.content_creator) throw new IqError.BAD_REQUEST("mismatching creator");
+
+        Iq.Stanza result_iq = new Iq.Stanza.result(iq) { to=peer_full_jid };
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, result_iq);
+
+        content.handle_content_modify(stream, content_node.senders);
+    }
+
+    private void handle_session_accept(Gee.List<ContentNode> content_nodes, StanzaNode jingle, Iq.Stanza iq) throws IqError {
+        string? responder_str = jingle.get_attribute("responder");
+        Jid responder = iq.from;
+        if (responder_str != null) {
+            try {
+                responder = new Jid(responder_str);
+            } catch (InvalidJidError e) {
+                warning("Received invalid session accept: %s", e.message);
+            }
+        }
+        // TODO(hrxi): more sanity checking, perhaps replace who we're talking to
+        if (!responder.is_full()) {
+            throw new IqError.BAD_REQUEST("invalid responder JID");
+        }
+        foreach (ContentNode content_node in content_nodes) {
+            handle_content_accept(content_node);
+        }
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
+
+        state = State.ACTIVE;
+    }
+
+    private void handle_session_terminate(StanzaNode jingle, Iq.Stanza iq) throws IqError {
+        string? reason_text = null;
+        string? reason_name = null;
+        StanzaNode? reason_node = iq.stanza.get_deep_subnode(NS_URI + ":jingle", NS_URI + ":reason");
+        if (reason_node != null) {
+            if (reason_node.sub_nodes.size > 2) warning("Jingle session-terminate reason node w/ >2 subnodes: %s", iq.stanza.to_string());
+
+            StanzaNode? specific_reason_node = null;
+            StanzaNode? text_node = null;
+            foreach (StanzaNode node in reason_node.sub_nodes) {
+                if (node.name == "text") {
+                    text_node = node;
+                } else if (node.ns_uri == NS_URI) {
+                    specific_reason_node = node;
+                }
+            }
+            reason_name = specific_reason_node != null ? specific_reason_node.name : null;
+            reason_text = text_node != null ? text_node.get_string_content() : null;
+
+            if (reason_name != null && !(specific_reason_node.name in ReasonElement.NORMAL_TERMINATE_REASONS)) {
+                warning("Jingle session terminated: %s : %s", reason_name ?? "", reason_text ?? "");
+            } else {
+                debug("Jingle session terminated: %s : %s", reason_name ?? "", reason_text ?? "");
+            }
+        }
+
+        foreach (Content content in contents.values) {
+            content.terminate(false, reason_name, reason_text);
+        }
+
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
+        // TODO(hrxi): also handle presence type=unavailable
+
+        state = State.ENDED;
+        terminated(stream, false, reason_name, reason_text);
+    }
+
+    private async void handle_session_info(StanzaNode jingle, Iq.Stanza iq) throws IqError {
+        StanzaNode? info = get_single_node_anyns(jingle);
+        if (info == null) {
+            // Jingle session ping
+            stream.get_module(Iq.Module.IDENTITY).send_iq(stream, new Iq.Stanza.result(iq));
+            return;
+        }
+        SessionInfoNs? info_ns = stream.get_module(Module.IDENTITY).get_session_info_type(info.ns_uri);
+        if (info_ns == null) {
+            throw new IqError.UNSUPPORTED_INFO("unknown session-info namespace");
+        }
+        info_ns.handle_content_session_info(stream, this, info, iq);
+
+        Iq.Stanza result_iq = new Iq.Stanza.result(iq) { to=peer_full_jid };
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, result_iq);
+    }
+
+    private void accept() {
+        if (state != State.INITIATE_RECEIVED) critical("Accepting a stream, but we're the initiator");
+
+        StanzaNode jingle = new StanzaNode.build("jingle", NS_URI)
+                .add_self_xmlns()
+                .put_attribute("action", "session-accept")
+                .put_attribute("sid", sid);
+        foreach (Content content in contents.values) {
+            StanzaNode content_node = new StanzaNode.build("content", NS_URI)
+                    .put_attribute("creator", "initiator")
+                    .put_attribute("name", content.content_name)
+                    .put_attribute("senders", content.senders.to_string())
+                    .put_node(content.content_params.get_description_node())
+                    .put_node(content.transport_params.to_transport_stanza_node());
+            jingle.put_node(content_node);
+        }
+        Iq.Stanza iq = new Iq.Stanza.set(jingle) { to=peer_full_jid };
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, iq);
+
+
+        foreach (Content content in contents.values) {
+            content.on_accept(stream);
+        }
+
+        state = State.ACTIVE;
+    }
+
+    internal void accept_content(Content content) {
+        if (state == State.INITIATE_RECEIVED) {
+            bool all_accepted = true;
+            foreach (Content c in contents.values) {
+                if (c.state != Content.State.WANTS_TO_BE_ACCEPTED) {
+                    all_accepted = false;
+                }
+            }
+            if (all_accepted) {
+                accept();
+            }
+        } else if (state == State.ACTIVE) {
+            StanzaNode content_accept_node = new StanzaNode.build("jingle", NS_URI)
+                    .add_self_xmlns()
+                    .put_attribute("action", "content-accept")
+                    .put_attribute("sid", sid)
+                    .put_node(new StanzaNode.build("content", NS_URI)
+                        .put_attribute("creator", "initiator")
+                        .put_attribute("name", content.content_name)
+                        .put_attribute("senders", content.senders.to_string())
+                        .put_node(content.content_params.get_description_node())
+                        .put_node(content.transport_params.to_transport_stanza_node()));
+
+            Iq.Stanza iq = new Iq.Stanza.set(content_accept_node) { to=peer_full_jid };
+            stream.get_module(Iq.Module.IDENTITY).send_iq(stream, iq);
+
+            content.on_accept(stream);
+        }
+    }
+
+    private void reject() {
+        if (state != State.INITIATE_RECEIVED) critical("Accepting a stream, but we're the initiator");
+        terminate(ReasonElement.DECLINE, null, "declined");
+    }
+
+    internal void reject_content(Content content) {
+        if (state == State.INITIATE_RECEIVED) {
+            reject();
+        } else {
+            warning("not really handeling content rejects");
+        }
+    }
+
+    public void set_application_error(StanzaNode? application_reason = null) {
+        terminate(ReasonElement.FAILED_APPLICATION, null, "application error");
+    }
+
+    public void terminate(string? reason_name, string? reason_text, string? local_reason) {
+        if (state == State.ENDED) return;
+
+        if (state == State.ACTIVE) {
+            string reason_str;
+            if (local_reason != null) {
+                reason_str = @"local session-terminate: $(local_reason)";
+            } else {
+                reason_str = "local session-terminate";
+            }
+            foreach (Content content in contents.values) {
+                content.terminate(true, reason_name, reason_text);
+            }
+        }
+
+        StanzaNode terminate_iq = new StanzaNode.build("jingle", NS_URI)
+                .add_self_xmlns()
+                .put_attribute("action", "session-terminate")
+                .put_attribute("sid", sid);
+        if (reason_name != null || reason_text != null) {
+            StanzaNode reason_node = new StanzaNode.build("reason", NS_URI);
+            if (reason_name != null) {
+                reason_node.put_node(new StanzaNode.build(reason_name, NS_URI));
+            }
+            if (reason_text != null) {
+                reason_node.put_node(new StanzaNode.text(reason_text));
+            }
+            terminate_iq.put_node(reason_node);
+        }
+        Iq.Stanza iq = new Iq.Stanza.set(terminate_iq) { to=peer_full_jid };
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, iq);
+
+        state = State.ENDED;
+        terminated(stream, true, reason_name, reason_text);
+    }
+
+    internal void send_session_info(StanzaNode child_node) {
+        if (state == State.ENDED) return;
+
+        StanzaNode node = new StanzaNode.build("jingle", NS_URI).add_self_xmlns()
+                .put_attribute("action", "session-info")
+                .put_attribute("sid", sid)
+                // TODO put `initiator`?
+                .put_node(child_node);
+        Iq.Stanza iq = new Iq.Stanza.set(node) { to=peer_full_jid };
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, iq);
+    }
+
+    internal void send_content_modify(Content content, Senders senders) {
+        if (state == State.ENDED) return;
+
+        StanzaNode node = new StanzaNode.build("jingle", NS_URI).add_self_xmlns()
+                .put_attribute("action", "content-modify")
+                .put_attribute("sid", sid)
+                .put_node(new StanzaNode.build("content", NS_URI)
+                    .put_attribute("creator", content.content_creator.to_string())
+                    .put_attribute("name", content.content_name)
+                    .put_attribute("senders", senders.to_string()));
+        Iq.Stanza iq = new Iq.Stanza.set(node) { to=peer_full_jid };
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, iq);
+    }
+
+    internal void send_transport_accept(Content content, TransportParameters transport_params) {
+        if (state == State.ENDED) return;
+
+        StanzaNode jingle_response = new StanzaNode.build("jingle", NS_URI)
+                .add_self_xmlns()
+                .put_attribute("action", "transport-accept")
+                .put_attribute("sid", sid)
+                .put_node(new StanzaNode.build("content", NS_URI)
+                .put_attribute("creator", "initiator")
+                .put_attribute("name", content.content_name)
+                .put_node(transport_params.to_transport_stanza_node())
+        );
+        Iq.Stanza iq_response = new Iq.Stanza.set(jingle_response) { to=peer_full_jid };
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, iq_response);
+    }
+
+    internal void send_transport_replace(Content content, TransportParameters transport_params) {
+        if (state == State.ENDED) return;
+
+        StanzaNode jingle = new StanzaNode.build("jingle", NS_URI)
+                .add_self_xmlns()
+                .put_attribute("action", "transport-replace")
+                .put_attribute("sid", sid)
+                .put_node(new StanzaNode.build("content", NS_URI)
+                .put_attribute("creator", "initiator")
+                .put_attribute("name", content.content_name)
+                .put_node(transport_params.to_transport_stanza_node())
+        );
+        Iq.Stanza iq = new Iq.Stanza.set(jingle) { to=peer_full_jid };
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, iq);
+    }
+
+    internal void send_transport_reject(Content content, StanzaNode transport_node) {
+        if (state == State.ENDED) return;
+
+        StanzaNode jingle_response = new StanzaNode.build("jingle", NS_URI)
+                .add_self_xmlns()
+                .put_attribute("action", "transport-reject")
+                .put_attribute("sid", sid)
+                .put_node(new StanzaNode.build("content", NS_URI)
+                .put_attribute("creator", "initiator")
+                .put_attribute("name", content.content_name)
+                .put_node(transport_node)
+        );
+        Iq.Stanza iq_response = new Iq.Stanza.set(jingle_response) { to=peer_full_jid };
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, iq_response);
+    }
+
+    internal void send_transport_info(Content content, StanzaNode transport) {
+        if (state == State.ENDED) return;
+
+        StanzaNode jingle = new StanzaNode.build("jingle", NS_URI)
+                .add_self_xmlns()
+                .put_attribute("action", "transport-info")
+                .put_attribute("sid", sid)
+                .put_node(new StanzaNode.build("content", NS_URI)
+                .put_attribute("creator", "initiator")
+                .put_attribute("name", content.content_name)
+                .put_node(transport)
+        );
+        Iq.Stanza iq = new Iq.Stanza.set(jingle) { to=peer_full_jid };
+        stream.get_module(Iq.Module.IDENTITY).send_iq(stream, iq);
+    }
+
+    public bool senders_include_us(Senders senders) {
+        switch (senders) {
+            case Senders.BOTH:
+                return true;
+            case Senders.NONE:
+                return false;
+            case Senders.INITIATOR:
+                return we_initiated;
+            case Senders.RESPONDER:
+                return !we_initiated;
+        }
+        assert_not_reached();
+    }
+
+    public bool senders_include_counterpart(Senders senders) {
+        switch (senders) {
+            case Senders.BOTH:
+                return true;
+            case Senders.NONE:
+                return false;
+            case Senders.INITIATOR:
+                return !we_initiated;
+            case Senders.RESPONDER:
+                return we_initiated;
+        }
+        assert_not_reached();
+    }
+}
\ No newline at end of file
diff --git a/xmpp-vala/src/module/xep/0166_jingle/session_info.vala b/xmpp-vala/src/module/xep/0166_jingle/session_info.vala
new file mode 100644
index 00000000..fcf7584f
--- /dev/null
+++ b/xmpp-vala/src/module/xep/0166_jingle/session_info.vala
@@ -0,0 +1,12 @@
+using Gee;
+using Xmpp.Xep;
+using Xmpp;
+
+namespace Xmpp.Xep.Jingle {
+
+    public interface SessionInfoNs : Object {
+        public abstract string ns_uri { get; }
+
+        public abstract void handle_content_session_info(XmppStream stream, Session session, StanzaNode info, Iq.Stanza iq) throws IqError;
+    }
+}
\ No newline at end of file