When using the key `pinentry` will be invoked to request the key's passphrase. The passphrase will be cached for up to 10 minutes idle time between uses, to a maximum of 2 hours.
## Remote Machines (agent forwarding)
If you want to use your YubiKey to sign a git commit on a remote machine, or ssh through another layer, then this is possible using "Agent Forwarding". This section should help you setup GPG and SSH agent forwarding.
To do this, you need to already have shell access to your remote machime, and your YubiKey setup on your host machine.
- First, on your local host machine run:
```
$ gpgconf --list-dirs agent-extra-socket
```
This should return a path to your agent-extra-socket, which should look similar to `/run/user/1000/gnupg/S.gpg-agent.extra`, though on older linux distros (and macs), it may be `/home/<user>/.gnupg/S/gpg-agent.extra`.
- Next, find the agent socket on your **remote** machine:
```
$ gpgconf --list-dirs agent-socket
```
This should return a path such as `/run/user/1000/gnupg/S.gpg-agent`.
- On your remote machine, edit the file `/etc/ssh/sshd_config`, so that option `StreamLocalBindUnlink` is set to `StreamLocalBindUnlink yes`
- _(optional)_If you do not have root access to the remote machine to edit `/etc/ssh/sshd_config`, you will need to remove the socket on the remote machine before forwarding works. For example, `rm /run/user/1000/gnupg/S.gpg-agent`. Further information can be found on the [AgentForwarding GNUPG wiki page](https://wiki.gnupg.org/AgentForwarding).
- Now you need to import your public keys to the remote machine. This can be done by fetching from a keyserver. Here we show how to copy your public keyring. On your local machine, you need to copy your public keyring to your remote machine
```
$ scp .gnupg/pubring.kbx remote:~/.gnupg/
```
- Finally, to enable agent forwarding for a given machine, add the following to your local machine's ssh config file `~/.ssh/config` (your agent sockets may be different):
You should then be able to use your YubiKey as if it were connected to the remote machine.
If you're still having problems, it may be necessary to edit your `gpg-agent.conf` file on both your remote and local machines to add the following information.
You can use YubiKey to sign GitHub commits and tags. It can also be used for GitHub SSH authentication, allowing you to push, pull, and commit without a password.
@ -1465,24 +1518,6 @@ StreamLocalBindUnlink yes
**Note** Agent forwarding may be chained through multiple hosts - just follow the same [protocol](#remote-host-configuration) to configure each host.
# Remote Machines (agent forwarding)
If you want to use your YubiKey to sign a git commit on a remote machine, or ssh through another layer, then this is possible using "Agent Forwarding". Assuming that you have your YubiKey setup on your host machine.
To enable agent forwarding, ssh using the `-A` flag:
```
$ ssh -A user@remote
```
Or add the following to your ssh config file:
```
Host remote
ForwardAgent yes
```
You should then be able to use your YubiKey as if it were connected to the remote machine.
# Troubleshooting
@ -1538,4 +1573,4 @@ You should then be able to use your YubiKey as if it were connected to the remot
drduh
5 years ago
committed by