Using the OpenSSH Beta in Windows 10 Fall Creators Update and Windows Server 1709
I’m thrilled to share that a Beta OpenSSH client and server daemon are available as a Feature-on-Demand in Windows 10 Fall Creators Update and Windows Server 1709. Since our last update blog, we’ve been working hard on a Win32 port of OpenSSH and working closely with members of the OpenSSH Portable and OpenBSD projects with the eventual goal of bringing Win32 support upstream into OpenSSH Portable.
Until then, you should expect OpenSSH support in Windows to continue to improve in future updates of Windows, including upcoming Windows Insider builds. You can track our progress on GitHub where you can find our wiki and the latest builds that include tons of fixes and support for operating systems downlevel to Windows 7 and Server 2008 R2.
OpenSSH is a collection of client/server utilities that enable secure remote login, remote file transfer, and public/private key pair management. It’s an extremely powerful tool that originated as part of the OpenBSD project, and has been used for many years across the BSD, Linux, macOS, and Unix ecosystems.
Note: The OpenSSH client and server are still very much in Beta, so we do not recommend using them in production environments.
Great! So how do I install the bits?
Installing with the Settings UI
To install it using the Settings UI, go to Apps -> Apps and Features -> Manage optional features -> Add a feature:
Then select OpenSSH Client (Beta) or OpenSSH Server (Beta) and Install:
Installing with PowerShell
To install OpenSSH using PowerShell, first launch PowerShell as an Administrator.
To make sure that the OpenSSH features are available for install:
Get-WindowsCapability -Online | ? Name -like 'OpenSSH*'
This should return the following output:
Name : OpenSSH.Client~~~~0.0.1.0 State : NotPresent Name : OpenSSH.Server~~~~0.0.1.0 State : NotPresent
Then, install the server and/or client features:
# Install the OpenSSH Client Add-WindowsCapability -Online -Name OpenSSH.Client~~~~0.0.1.0 # Install the OpenSSH Server Add-WindowsCapability -Online -Name OpenSSH.Server~~~~0.0.1.0
Both of these should return the following output:
Path : Online : True RestartNeeded : False
Installing with DISM.exe
To install OpenSSH with DISM.exe, first open CMD as an Administrator.
To make sure that OpenSSH features are available for install:
dism /Online /Get-Capabilities | findstr OpenSSH
This should return the following output:
Capability Identity : OpenSSH.Client~~~~0.0.1.0 Capability Identity : OpenSSH.Server~~~~0.0.1.0
Then, install the server and/or client features:
dism /Online /Add-Capability /CapabilityName:OpenSSH.Client~~~~0.0.1.0 dism /Online /Add-Capability /CapabilityName:OpenSSH.Server~~~~0.0.1.0
Great! You’ve installed OpenSSH. What now?
Configuring the SSH Client (ssh.exe)
If you want to use the SSH client with password authentication, no configuration is necessary. Just pop open PowerShell or cmd, and use
ssh to connect to your SSH server:
ssh firstname.lastname@example.org # You can also use domain accounts to login # UPN syntax works... ssh user1@email@example.com # ...as does NetBIOS syntax ssh user1\firstname.lastname@example.org
If you want to use key-based authentication, you first need to generate some public/private key pairs for your client. From PowerShell or cmd, use
ssh-keygen to generate some key files.
cd ~\.ssh\ ssh-keygen
This should output something like:
Generating public/private ed25519 key pair. Enter file in which to save the key (C:\Users\user1\.ssh\id_ed25519):
You can hit Enter to accept the default or specify a path where you’d like your keys to be generated. At this point, you’ll be prompted to use a passphrase to encrypt your private key files.
Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in C:\Users\user1\.ssh\id_ed25519. Your public key has been saved in C:\Users\user1\.ssh\id_ed25519.pub. The key fingerprint is: SHA256:OIzc1yE7joL2Bzy8/gS0j8eGK7bYaH1FmF3sDuMeSj8 user1@CONTOSO@LOCAL-HOSTNAME The key's randomart image is: +--[ED25519 256]--+ | . | | o | | . + + . | | o B * = . | | o= B S . | | .=B O o | | + =+% o | | *oo.O.E | |+.o+=o. . | +----[SHA256]-----+
Now you have a public/private ED25519 key pair (the .pub files are public keys and the rest are private keys):
Mode LastWriteTime Length Name ---- ------------- ------ ---- -a---- 11/8/2017 11:09 AM 1679 id_ed25519 -a---- 11/8/2017 11:09 AM 414 id_ed25519.pub
Your private key files are the equivalent of a password. You should protect them under any and all circumstances. If someone acquires your private key, they can log in to any SSH server as an identity that authorizes the corresponding public key to log in.
For that reason, we should take advantage of
ssh-agent to securely store the private keys within a Windows security context. To do that, we simply start the
ssh-agent service (as Administrator) and use
ssh-add to store our private key. Then, whenever a private key is needed for authentication,
ssh-agent will automatically retrieve your local user’s private key and pass it to your SSH client.
# Make sure you're running as an Administrator Start-Service ssh-agent # This should return a status of Running Get-Service ssh-agent # Now load your key files into ssh-agent ssh-add ~\.ssh\id_ed25519 # Now that it's loaded into ssh-agent, # we don't have to keep the key file anymore Remove-Item ~\.ssh\id_ed25519
Move the contents of your public key (
~\.ssh\id_ed25519.pub) into a text file called
~\.ssh\ on your server/host.
Note: these directions assume your sshd server is a Windows-based machine using our OpenSSH-based server, and that you’ve properly configured it based on the instructions below (including the installation of the
OpenSSHUtils PowerShell module). If you’re using a non-Windows machine, you should replace all remote instances of
C:\users\user1 with something like
/home/user1. Additionally, the ACL line should be unnecessary that uses PowerShell should be unnecessary.
# Make sure that the .ssh directory exists in your server's home folder ssh user1@email@example.com mkdir C:\users\user1\.ssh\ # Copy your public key file to authorized_keys on your server scp C:\Users\user1\.ssh\id_ed25519.pub user1@firstname.lastname@example.org:C:\Users\user1\.ssh\authorized_keys # Appropriately ACL the authorized_keys file on your server ssh --% user1@email@example.com powershell -c $ConfirmPreference = 'None'; Repair-AuthorizedKeyPermission C:\Users\user1\.ssh\authorized_keys
Congrats! You should no longer need a password when authenticating as
Configuring the OpenSSH Server (sshd)
First, it’s worth noting again that this OpenSSH for Windows is still very much in beta form. It should only be used in safe, testing environments.
To enable authentication into an SSH server on Windows, you first have to generate host keys. As an Administrator:
Start-Service ssh-agent cd C:\Windows\System32\OpenSSH .\ssh-keygen -A # C:\Windows\System32\OpenSSH\ssh-keygen.exe: generating new host keys: ED25519 .\ssh-add ssh_host_ed25519_key # Identity added: .\ssh_host_ed25519_key (User1@CONTOSO@LOCAL-HOSTNAME)
Due to certain security requirements, you will also have to install our
OpenSSHUtils helper module to appropriately ACL your host keys. As an Administrator:
Install-Module -Force OpenSSHUtils Repair-SshdHostKeyPermission -FilePath C:\Windows\System32\OpenSSH\ssh_host_ed25519_key # Use A or Y as your response to the prompts to set file owners
Then you can start sshd and your server is ready to go:
Start-Service sshd # This should return a Status of Running Get-Service sshd
Note: currently only the built-in ED25519 authentication key type is supported. In the future, we plan to add support for LibreSSL which will enable additional authentication key types. In the meantime, you can experiment with LibreSSL builds on GitHub.
You may also need to add a firewall rule like this one that allows traffic on port 22 (though your requirements may vary based on your environment, e.g.
Domain might be
New-NetFirewallRule -Name sshd -DisplayName 'OpenSSH Server (sshd)' -Service sshd -Enabled True -Direction Inbound -Protocol TCP -Action Allow -Profile Domain
Enjoy playing with OpenSSH on Windows, and keep your eyes peeled on the PowerShell blog for upcoming news.
Hi there. Markup in code examples is broken. Can you please fix it? Best regards, V.
When installing OpenSSH-Server as regular “Feature on Demand” on Win10, are (especially security-related) Updates for SSHD provided automatically?
If yes, how and when are they applied? During Windows-Update on a monthly basis?
Is there a Service-Level provided by Microsoft for Updating the FoD “OpenSSH-Server”? If yes, does it depend on the Windows-Release, e.g. is there a difference between Win10 v1903 and Win10 LTSC 2019?
My expectation is, that security-relevant Bugs in OpenSSH-Daemon are fixed by Microsoft and Updated by Windows-Update. Is this expectation correct? If not, what can we expect?
Can you help me with these point below :
A- How Can i change or create root of SFTP on F:/ .
B- How can do user restrict on Openssh
thank you .
Not sure where to file bug reports, but the latest version of sftp does not handle REPARSE-POINTS correctly. For example, trying to recurse into “C:\Users\myusername\AppData\Local\Application Data”, using WinSCP generates the error:
Bad Message (badly formatted packet or protocol incompatibility).
Error code: 5
Error message from server: Bad message
We also tried using the python paramiko module with identical results (http://docs.paramiko.org/en/2.7/api/sftp.html#paramiko.sftp_attr.SFTPAttributes).
It would be useful the returned st_mode included some sort of “it’s a symlink” indicator to allow software applications to handle REPARSE-POINTS more gracefully.
Please file issues at https://github.com/powershell/Win32-OpenSSH
I’m trying to figure out what I can claim about FIPS 140-2 and CMVP ‘compliance’ while using this OpenSSH or SFTP on Windows 10.
Windows 10 crypto seems to be in good shape and many commercial *nixes have validated their OpenSSH implementations but that doesn’t necessarily mean OpenSSH on Windows 10 is using a validated module.
Can anyone expand on this?