Using TREZOR as a hardware SSH agent

See SatoshiLabs' blog post about this feature:

• https://medium.com/@satoshilabs/trezor-firmware-1-3-4-enables-ssh-login-86a622d7e609

Screencast demo usage

Simple usage (single SSH session)

Advanced usage (multiple SSH sessions from a sub-shell)

Using for GitHub SSH authentication (via trezor-git utility)

Installation

First, make sure that the latest trezorlib Python package is installed correctly (at least v0.6.6):

$ apt-get install python-dev libusb-1.0-0-dev libudev-dev
$ pip install Cython trezor

Then, install the latest trezor_agent package:

$ pip install trezor_agent

Finally, verify that you are running the latest TREZOR firmware version (at least v1.3.4):

$ trezorctl get_features
vendor: "bitcointrezor.com"
major_version: 1
minor_version: 3
patch_version: 4
...

Public key generation

Run:

/tmp $ trezor-agent ssh.hostname.com -v > hostname.pub
2015-09-02 15:03:18,929 INFO         getting "ssh://ssh.hostname.com" public key from Trezor...
2015-09-02 15:03:23,342 INFO         disconnected from Trezor
/tmp $ cat hostname.pub
ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBGSevcDwmT+QaZPUEWUUjTeZRBICChxMKuJ7dRpBSF8+qt+8S1GBK5Zj8Xicc8SHG/SE/EXKUL2UU3kcUzE7ADQ= ssh://ssh.hostname.com

Append hostname.pub contents to ~/.ssh/authorized_keys configuration file at ssh.hostname.com, so the remote server would allow you to login using the corresponding private key signature.

Usage

Run:

/tmp $ trezor-agent ssh.hostname.com -v -c
2015-09-02 15:09:39,782 INFO         getting "ssh://ssh.hostname.com" public key from Trezor...
2015-09-02 15:09:44,430 INFO         please confirm user "roman" login to "ssh://ssh.hostname.com" using Trezor...
2015-09-02 15:09:46,152 INFO         signature status: OK
Linux lmde 3.16.0-4-amd64 #1 SMP Debian 3.16.7-ckt11-1+deb8u3 (2015-08-04) x86_64

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Tue Sep  1 15:57:05 2015 from localhost
~ $

Make sure to confirm SSH signature on the Trezor device when requested.