remoteu2f is a project that enables the use of a FIDO U2F security key remotely, through a lightly-trusted proxy.

This project is DEPRECATED.
The U2F API is unsupported in modern browsers, and the project hasn't been updated to the new WebAuthn standard.

It is useful mainly to use as a second factor authentication for ssh and sudo-over-ssh.
For example:

It's written in Go, with some C for PAM integration.
It uses grpc for the RPC layer, tstranex/u2f to perform U2F operations, and codegangsta/cli for the CLI.

It's open source under the MIT licence.


This example shows how to initialize the configuration and register a key on the server, and how ssh looks like when using remoteu2f. The installation instructions have more details.


For now, download is only available via git:
git clone

The installation instructions cover how to use go get to install the different components.

Patches are welcome. You can also browse the git repository online.