Pluginized QUIC

Pluginized QUIC is a framework that enables QUIC clients and servers to dynamically exchange protocol plugins that extend the protocol on a per-connection basis.

March 2020 update: Pluginized QUIC is now updated to the latest QUIC specification (draft-27).

All the source code of this project is available on GitHub.


Getting started

Compiling PQUIC

During this process, we assume our base working directory is working_dir. First, you need to clone picotls which provides the TLS implementation on which PQUIC is based. It itself requires openssl.

$ apt install openssl-dev  # or dnf install openssl-devel
$ cd working_dir
$ git clone https://github.com/p-quic/picotls.git
$ cd picotls
# the following instructions just come from the picotls README
$ git submodule init
$ git submodule update
$ cmake .
# cmake might fail if some dependencies are not met, so install them and retry the cmake
$ make
# once picotls is compiled, just go back to the working directory
$ cd ..
# pwd should return working_dir

Once picotls is set up, you can compile pquic with the following commands.

$ git clone https://github.com/p-quic/pquic
$ cd pquic
# install libarchive, used for the plugin exchange (on Fedora, dnf install libarchive-devel)
$ sudo apt install libarchive-dev
# fetch and compile ubpf, the virtual machine used within PQUIC
$ git submodule update --init
$ cd ubpf/vm
$ make
# make might generate warnings, but should compile
$ cd ../..
# also install gperftools, required in the current build process (on Fedora, dnf install gperftools)
$ sudo apt install gperftools
$ cmake .
# if all the dependencies are present, cmake should not report any issue
$ make

At the end of this process, you should have generated several executables, including picoquicdemo which can act as both the PQUIC client and server.

Checking that picoquicdemo works

Before going further, let’s check that our compiled code can exchange data. Depending on the provided arguments, picoquicdemo either acts as a (P)QUIC client or a (P)QUIC server. Let’s generate our first connection!

For convenience, let’s open two different terminals. In the first one, we will launch the server as shown below.

$ cd working_dir/pquic
$ ./picoquicdemo
Starting PicoQUIC server on port 4443, server name = ::, just_once = 0, hrr= 0, 0 local plugins and 0 both plugins

Now on the other terminal, launch the client as follows.

$ cd working_dir/pquic
$ ./picoquicdemo ::1 4443

A lot of logs should be shown, but in the last lines of the client, you should see that the connection successfully completed without error. Great!

Compiling your first plugin

Now that the base implementation works well, let’s modify it a little such that it protects the exchanged data with Forward Erasure Correction. The fec plugin exactly does this, but first of all, we need to compile it into eBPF code.

For the compilation process, you need clang-6.0 and llc-6.0. You can install them by following the process at https://apt.llvm.org/. More recent versions might work, but in this case you need to modify the CLANG and LLC variables in the Makefiles in the plugin source code folders. Then, you can compile the fec plugin as follows.

$ cd working_dir/pquic
$ cd plugins/fec
$ make
# if it raises an error about clang-6.0 not found, update the CLANG and LLC variables in Makefile

That’s it! Several objects files should have been generated. Each of them are ELF files containing the eBPF code implementing the plugin behavior. Let’s plug them in PQUIC!

Running your first plugin inside PQUIC

As in our first run of picoquicdemo, open two terminals. In the first one, we will launch the server with the fec plugin as follows.

$ cd working_dir/pquic
$ ./picoquicdemo -P plugins/fec/fec.plugin
Starting PicoQUIC server on port 4443, server name = ::, just_once = 0, hrr= 0, 1 local plugins and 0 both plugins
	local plugin plugins/fec/fec.plugin

And on the other terminal, we launch the client with the fec plugin as follows. Notice that here, for simpler log processing, we limit the transfer exchange to 10 KB by using the -G and -4 options.

$ cd working_dir/pquic
$ ./picoquicdemo -4 -G 10000 -P plugins/fec/fec.plugin ::1 4443

A quick look at the client log shows that new frames, SFPID FRAME, are used over the connection. These frames are specific to the injected fec plugin, showing that we achieved to inject Forward Erasure Correction to this connection. Wonderful!