This is a userspace path manager for the linux multipath TCP kernel, starting from version v0.95.

This allows to monitor MPTCP connections and control what subflows to create and with a custom kernel it can even set specific values for the congestion windows.

Compilation

For now we need a custom version of netlink With a custom netlink and kernel Compile the custom netlink library with

$ cabal configure --enable-library-profiling

You may need some headers as well (NOTE: reference cabal.project instead):

kernel $ make headers_install
$ cabal configure --package-db ~/netlink-hs/dist/package.conf.inplace --extra-include-dirs=~/mptcp/build/usr/include -v3 --enable-profiling

To compile the doc (and understand why HLS fails displaying anything) cabal haddock --all

Usage

The netlink module asks for GENL_ADMIN_PERM which requires the CAP_NET_ADMIN privilege. You can assign this privilege via:

sudo setcap cap_net_admin+ep hs/dist-newstyle/build/x86_64-linux/ghc-8.6.3/netlink-pm-1.0.0/x/daemon/build/daemon/daemon

Enter the development shell and start the daemon:

$ nix develop
$ cabal run daemon

TODO

• remove the need for MptcpSocket everywhere: it's just needed to write the header, which could be added/modifier later instead ! (to increase purity in the library)
• we need to better keep track of subflow status (established vs WIP) ?
• pass local/server IPs as commands to the PM ?
• generate completion scripts via --zsh-completion-script

Acknowledgements

This work is sponsored by NGI.