How to share OpenSSH keys with WSL in Windows 10

Don't want to copy over your ssh keys from Windows to WSL 2 Linux? Or generate new ones? Then share your Windows OpenSSH key with WSL 2! The OpenSSH config gives you the option to share keys using an IdentityFile directive. Here is how you can share your SSH keys between Windows 11/10 and WSL 2.

The SSH config directive IdentityFile specifies a file from which the user's DSA, ECDSA, authenticator-hosted ECDSA, Ed25519, authenticator hosted Ed25519 or RSA authentication identity is read. You can use this to share your Windows OpenSSH key with WSL. Assuming you've created a key pair in Windows using ssh-keygen.

Manually install OpenSSH in Windows Server
Retrieve SSH public key from Active Directory for SSH authentication

First start with creating a symlink in WSL from ~/.ssh to /mnt/c/Users/exampleuser/.ssh/. Substitute "exampleuser" with your user name:

ln -s /mnt/c/Users/exampleuser/.ssh ~/.ssh

Next, create a file /etc/wsl.conf, and add the following contents:

[automount]
options = "metadata,mask=22,fmask=11"

This is required because Linux uses a different user/group system than Windows does, and using this automount option adds specific metadata. Source: Chmod/Chown WSL Improvements. You also have to fix file permissions on ~/.ssh, the keys and config files:

chmod 600 ~/.ssh
chmod 644 ~/.ssh/id_ed25519
chmod 644 ~/.ssh/config

Last, open up your ssh config file in Windows, which is located in C:\Users\exampleuser\.ssh, and add two IdentityFile lines. One using your Windows path and one the WSL Linux path:

Host *.example.org
	IdentityFile	c:/users/exampleuser/.ssh/id_ed25519
	IdentityFile	/mnt/c/Users/exampleuser/.ssh/id_ed25519
	User exampleuser
	ForwardAgent yes

ForwardAgent specifies whether the connection to the authentication agent (if any) will be forwarded to the remote machine. If you have the ssh-agent service running in Windows, you can use this to connect to a host where you don't have an authorized_keys available yet by ssh'ing into a jump host. Use with caution.

Tunnel RDP through SSH & PuTTY
Set up Monit monitoring in Windows Subsystem for Linux WSL

Thank you very much! <3 ❤️