VPN-friendly networking devices for HyperKit
Binary artefacts are built by CI:
VPNKit is a set of tools and services for helping HyperKit VMs interoperate with host VPN configurations.
First install wget, opam using your package manager of choice.
Build all the dependencies and the program itself with:
cd [path to vpnkit source]
opam remote add vpnkit ./repo/darwin
opam install --deps-only slirp
make
When the build succeeds the vpnkit binary should be available in the current path.
First ask vpnkit to listen for ethernet connections on a local Unix domain socket:
vpnkit --ethernet /tmp/ethernet --debug
Next ask com.docker.hyperkit to connect a NIC to this
socket by adding a command-line option like -s 2:0,virtio-vpnkit,path=/tmp/ethernet. Note:
you may need to change the slot 2:0 to a free slot in your VM configuration.
Running a VM usually involves modifying the network configuration on the host, for example by activating Ethernet bridges, new routing table entries, DNS and firewall/NAT configurations. Activating a VPN involves modifying the same routing tables, DNS and firewall/NAT configurations and therefore there can be a clash -- this often results in the network connection to the VM being disconnected.
VPNKit, part of HyperKit attempts to work nicely with VPN software by intercepting the VM traffic at the Ethernet level, parsing and understanding protocols like NTP, DNS, UDP, TCP and doing the "right thing" with respect to the host's VPN configuration.
VPNKit operates by reconstructing Ethernet traffic from the VM and translating it into the relevant socket API calls on OSX or Windows. This allows the host application to generate traffic without requiring low-level Ethernet bridging support.