From 7858d6e9e2e3aa118638676a202e600fc9668986 Mon Sep 17 00:00:00 2001 From: Nathan Skrzypczak Date: Mon, 29 Jul 2019 13:51:31 +0200 Subject: docs: Add more quic plugin documentation Type: docs Change-Id: I0209769f73a46ddad7c2625ad0f774ee2eef43dd Signed-off-by: Nathan Skrzypczak --- src/plugins/quic/quic_doc.md | 38 ------------ src/plugins/quic/quic_plugin.rst | 127 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 127 insertions(+), 38 deletions(-) delete mode 100644 src/plugins/quic/quic_doc.md create mode 100644 src/plugins/quic/quic_plugin.rst (limited to 'src') diff --git a/src/plugins/quic/quic_doc.md b/src/plugins/quic/quic_doc.md deleted file mode 100644 index 6ffd00c5ce7..00000000000 --- a/src/plugins/quic/quic_doc.md +++ /dev/null @@ -1,38 +0,0 @@ -# QUIC implementation {#quic_doc} - -The quic plugin provides an IETF QUIC protocol implementation. It is based on -the [quicly](https://github.com/h2o/quicly) library. - -This plugin adds the QUIC protocol to VPP's Host Stack. As a result QUIC is -usable both in internal VPP applications and in external apps. - - -## Maturity level -Under development: it should mostly work, but has not been thoroughly tested and -should not be used in production. - - -## Features - - only bidirectional streams are supported currently. - - -## Getting started - -QUIC constructs are exposed as follows: - -- QUIC connections and streams are both regular host stack sessions. -- QUIC connections can be created and destroyed with regular `connect` and - `close` calls with `TRANSPORT_PROTO_QUIC`. -- Streams can be opened in a connection by calling `connect`again and passing - the ID of the connection to which the new stream should belong. -- Streams can be closed with a regular `close`call. -- Streams opened by peers can be accepted from the sessions corresponding to - QUIC connections. -- Data can ba exchanged by using the regular `send` and `recv` calls on the - stream sessions. - -Example code can be found in: -`src/vnet/session-apps/echo_client.c`: Test client using the internal API -`src/vnet/session-apps/echoo_server.c`: Test server using the internal API -`src/tests/vnet/session/quic_echo.c`: Client and server, using the external API - diff --git a/src/plugins/quic/quic_plugin.rst b/src/plugins/quic/quic_plugin.rst new file mode 100644 index 00000000000..3160eb442f8 --- /dev/null +++ b/src/plugins/quic/quic_plugin.rst @@ -0,0 +1,127 @@ +.. _quic_plugin: +.. _quicly: https://github.com/h2o/quicly + +.. toctree:: + +QUIC HostStack +============== + +The quic plugin provides an `IETF QUIC protocol `_ implementation. It is based on +the quicly_ library. + +This plugin adds the QUIC protocol to VPP's Host Stack. As a result QUIC is +usable both in internal VPP applications and in external apps. + +**Maturity** + +- This plugin is under current development: it should mostly work, but has not been thoroughly tested and should not be used in production. +- Only bidirectional streams are supported currently. + +Getting started +--------------- + +* A common sample setup is with two vpp instances interconnected #twovppinstances +* Ensure your vpp configuration file contains ``session { evt_qs_memfd_seg }`` +* Then run ``session enable`` in the debug cli (vppctl) + +This plugin can be tested in the following cases. + +Internal client +^^^^^^^^^^^^^^^ + +This application is a simple command to be run on the debug cli to test connectivity & throughput on QUIC over the debug cli (vppctl). It does not reflect reality and is mostly used for internal tests. + +* Run ``test echo server uri quic://1.1.1.1/1234`` on your first instance +* Then ``test echo client uri quic://20.20.1.1/1`` on the second one + +Source for the internal client lives in ``src/plugins/hs_apps/echo_client.c`` + +External client +^^^^^^^^^^^^^^^ + +This setup reflects the use case of an app developper using vpp to create a quic client / server. The application is an external binary that connects to VPP via its binary API. + +After having setup two interconnected vpps, you can attach the quic_echo binary to each of them. + +* The binary can be found in ``./build-root/build-vpp[_debug]-native/vpp/bin/quic_echo`` +* To run the client & server use ``quic_echo socket-name /vpp.sock client|server uri quic://1.1.1.1/1234`` +* Several options are available to customize the amount of data sent, number of threads, logging and timinig. + +The behavior of this app when run with ``nclient 2/4`` is two first establish 2 connections with the given peer, and once everything has been openend start opening 4 quic streams, and transmit data. Flow is as follows. + +.. image:: /_images/quic_plugin_echo_flow.png + +This allows timinig of either the whole setup & teardown or specific phases in assessing the protocol's performance + +Source for the internal client lives in ``src/plugins/hs_apps/sapi/quic_echo.c`` + +VCL client +^^^^^^^^^^ + +The hoststack exposes a simplified API call the VCL (blocking posix like calls), this API is used by a sample client & server implementation that supports QUIC, TCP and UDP. + +* The binaries can be found in ``./build-root/build-vpp[_debug]-native/vpp/bin/`` +* Create the VCL conf files ``echo "vcl { api-socket-name /vpp.sock }" | tee /tmp/vcl.conf]`` +* For the server ``VCL_CONFIG=/tmp/vcl.conf ; vcl_test_server -p QUIC 1234"`` +* For the client ``VCL_CONFIG=/tmp/vcl.conf ; vcl_test_client -p QUIC 1.1.1.1 1234"`` + +Source for the internal client lives in ``src/plugins/hs_apps/vcl/vcl_test_client.c`` + +A basic usage is the following client side + +.. code-block:: C + + #include + int fd = vppcom_session_create (VPPCOM_PROTO_QUIC); + vppcom_session_tls_add_cert (/* args */); + vppcom_session_tls_add_key (/* args */); + vppcom_session_connect (fd, "quic://1.1.1.1/1234"); /* create a quic connection */ + int sfd = vppcom_session_create (VPPCOM_PROTO_QUIC); + vppcom_session_stream_connect (sfd, fd); /* open a quic stream on the connection*/ + vppcom_session_write (sfd, buf, n); + +Server side + +.. code-block:: C + + #include + int lfd = vppcom_session_create (VPPCOM_PROTO_QUIC); + vppcom_session_tls_add_cert (/* args */); + vppcom_session_tls_add_key (/* args */); + vppcom_session_bind (fd, "quic://1.1.1.1/1234"); + vppcom_session_listen (fd); + int fd = vppcom_session_accept (lfd); /* accept quic connection*/ + vppcom_session_is_connectable_listener (fd); /* is true */ + int sfd = vppcom_session_accept (fd); /* accept quic stream */ + vppcom_session_is_connectable_listener (sfd); /* is false */ + vppcom_session_read (sfd, buf, n); + + +Internal Mechanics +------------------ + +QUIC constructs are exposed as follows: + +- QUIC connections and streams are both regular host stack session, exposed via the API with their 64bits handle. +- QUIC connections can be created and destroyed with regular ``connect`` and ``close`` calls with ``TRANSPORT_PROTO_QUIC``. +- Streams can be opened in a connection by calling ``connect`` again and passing the handle of the connection to which the new stream should belong. +- Streams can be closed with a regular ``close`` call. +- Streams opened by peers can be accepted from the sessions corresponding to QUIC connections. +- Data can ba exchanged by using the regular ``send`` and ``recv`` calls on the stream sessions. + +Data structures +^^^^^^^^^^^^^^^ + +Quic relies on the hoststack constructs, namely applications, sessions, transport_connections, and app_listeners. When listening on a port with the quic protocol, an external application : + +* Attaches to vpp and register an ``application`` +* It creates an ``app_listener`` and a ``quic_listen_session``. +* The ``quic_listen_session`` relies on a ``transport_connection`` (``lctx``) to access the underlying ``udp_listen_session`` that will receive packets. +* Upon connection request, we create the same data structure (``quic_session``, ``qctx``, ``udp_session``) and pass a handle to the ``quic_session`` in the accept callback to acknowledge the creation of a quic connection. All further UDP datagrams for the peers at each end of the connection will be exchanged through the ``udp_session`` +* Upon receiving a Stream opening request, we create the ``stream_session`` and its transport ``sctx`` and pass the handle to the ``stream_session`` back to the app. Here we don't have any UDP datastructures, as all datagrams are bound to the connection. + + +Thoses structures are linked as follows : + +.. image:: /_images/quic_plugin_datastructures.png + -- cgit 1.2.3-korg