Connect to windows ssh from linux

В последних билдах Windows 10 появился встроенный SSH сервер и клиент на базе OpenSSH. Это значит, что теперь вы можете удаленно подключаться к компьютеру Windows 10/11 (Windows Server 2019/2022) с помощью любого SSH клиента, как к Linux. В этой статье мы покажем, как настроить OpenSSH в Windows 10 и подключится к нему с помощью putty или любого другого SSH клиента.

Убедитесь, что ваша версия Windows 10 1809 или выше. Проще всего это сделать, выполнив команду:

winver

Вы можете включить OpenSSH сервера в Windows 10 через панель Параметры:

1. Перейдите в Settings -> Apps -> Optional features;
2. Нажмите Add a feature, выберите OpenSSH Server и нажмите Install;

Также вы можете установить sshd сервер в Windows с помощью PowerShell:

Add-WindowsCapability -Online -Name OpenSSH.Server*

Или с помощью DISM:

dism /Online /Add-Capability /CapabilityName:OpenSSH.Server~~~~0.0.1.0

Если вы хотите убедитесь, что OpenSSH сервер установлен, выполните следующую команду:

Get-WindowsCapability -Online | ? Name -like 'OpenSSH.Server*'

Name : OpenSSH.Server~~~~0.0.1.0
State : Installed

Проверьте статус служб ssh-agent и sshd с помощью командлета Get-Service:

Get-Service -Name *ssh*

Как вы видите, обе службы находятся в состоянии Stopped и не добавлены в автозагрузку. Чтобы запустить службы и настроить для них автозапуск, выполните команды:

Start-Service sshd
Set-Service -Name sshd -StartupType 'Automatic'
Start-Service ‘ssh-agent’
Set-Service -Name ‘ssh-agent’ -StartupType 'Automatic'

Также нужно разрешить входящие подключения на порт TCP 22 в Windows Defender Firewall:

netsh advfirewall firewall add rule name="SSHD service" dir=in action=allow protocol=TCP localport=22

Теперь вы можете подключиться к Windows 10 с помощью любого SSH клиента. Для подключения из Linux используете команду:

ssh -p 22 admin@192.168.1.90

где, admin – имя локального пользователя Windows, под которым вы хотите подключиться

192.168.1.90 – ip адрес вашего компьютера с Windows 10

После этого откроется окно командной строки Windows.

Если вы хотите использовать key-based ssh authentification вместо парольной аутентификации, нужно на вашем клиенте сгенерировать ключ с помощью ssh-keygen.exe.

Затем содержимое файла id_rsa.pub нужно скопировать в файл c:\users\admin\.ssh\authorized_keys в Windows 10.

После этого вы сможете подключаться с вашего Linux клиента к Windows 10 без пароля. Используйте команду:

ssh -l admin@192.168.1.90

Вы можете настроить различные параметры OpenSSH сервера в Windows с помощью конфигурационного файла %programdata%\ssh\sshd_config

Например, вы можете отключить аутентификацию по паролю и разрешить вход только по ключу:

PubkeyAuthentication yes
PasswordAuthentication no

I need to SSH from Ubuntu server into Windows 10 (OpenSSH). Everything is fine when I connect using username and password, but I have trouble if I introduce RSA key

1. On Linux I ran ssh-keygen and generated ‘id_rsa’ and ‘id_rsa.pub’ without passphrase (location ~/.ssh).

2. On Windows I copy/pasted content of id_rsa.pub into C:\Users\foobar\.ssh\authorized_keys

3. On Linux I try to connect with following command

ssh -i /home/foobar/.ssh/id_rsa 192.168.100.101

but it just asks for password for user ‘foobar’ anyway, which if I enter allows me in without problem, but it does not use the key.

What am I missing? My best guess is that something’s wrong on Windows end, but what?

Here is the verbose output:

autotunnel@ercserver:~$ ssh -v -i /home/autotunnel/.ssh/id_rsa 192.168.100.101
OpenSSH_8.2p1 Ubuntu-4ubuntu0.1, OpenSSL 1.1.1f  31 Mar 2020
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: include /etc/ssh/ssh_config.d/*.conf matched no files
debug1: /etc/ssh/ssh_config line 21: Applying options for *
debug1: Connecting to 192.168.100.101 [192.168.100.101] port 22.
debug1: Connection established.
debug1: identity file /home/autotunnel/.ssh/id_rsa type 0
debug1: identity file /home/autotunnel/.ssh/id_rsa-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_8.2p1 Ubuntu-4ubuntu0.1
debug1: Remote protocol version 2.0, remote software version OpenSSH_for_Windows_7.7
debug1: match: OpenSSH_for_Windows_7.7 pat OpenSSH* compat 0x04000000
debug1: Authenticating to 192.168.100.101:22 as 'autotunnel'
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: algorithm: curve25519-sha256
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: [email protected] MAC: <implicit> compression: none
debug1: kex: client->server cipher: [email protected] MAC: <implicit> compression: none
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:uk5rA8yTEzwrtTOQqC04u5SKnv56BbA1pBSiafkV3Ro
debug1: Host '192.168.100.101' is known and matches the ECDSA host key.
debug1: Found key in /home/autotunnel/.ssh/known_hosts:1
debug1: rekey out after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: rekey in after 134217728 blocks
debug1: Will attempt key: /home/autotunnel/.ssh/id_rsa RSA SHA256:7RJoq/HURzcbte/G+GI0/CY3ed6B44mDt+GevScznFI explicit
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<ssh-ed25519,ssh-rsa,rsa-sha2-256,rsa-sha2-512,ssh-dss,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521>
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug1: Next authentication method: publickey
debug1: Offering public key: /home/autotunnel/.ssh/id_rsa RSA SHA256:7RJoq/HURzcbte/G+GI0/CY3ed6B44mDt+GevScznFI explicit
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug1: Next authentication method: keyboard-interactive
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug1: Next authentication method: password
[email protected]'s password:

and here is the sshd_config

# This is the sshd server system-wide configuration file.  See
# sshd_config(5) for more information.

# The strategy used for options in the default sshd_config shipped with
# OpenSSH is to specify options with their default value where
# possible, but leave them commented.  Uncommented options override the
# default value.

#Port 22
#AddressFamily any
#ListenAddress 0.0.0.0
#ListenAddress ::

#HostKey __PROGRAMDATA__/ssh/ssh_host_rsa_key
#HostKey __PROGRAMDATA__/ssh/ssh_host_dsa_key
#HostKey __PROGRAMDATA__/ssh/ssh_host_ecdsa_key
#HostKey __PROGRAMDATA__/ssh/ssh_host_ed25519_key

# Ciphers and keying
#RekeyLimit default none

# Logging
#SyslogFacility AUTH
#LogLevel INFO

# Authentication:

#LoginGraceTime 2m
#PermitRootLogin prohibit-password
#StrictModes yes
#MaxAuthTries 6
#MaxSessions 10

PubkeyAuthentication yes

# The default is to check both .ssh/authorized_keys and .ssh/authorized_keys2
# but this is overridden so installations will only check .ssh/authorized_keys
AuthorizedKeysFile  .ssh/authorized_keys

#AuthorizedPrincipalsFile none

# For this to work you will also need host keys in %programData%/ssh/ssh_known_hosts
#HostbasedAuthentication no
# Change to yes if you don't trust ~/.ssh/known_hosts for
# HostbasedAuthentication
#IgnoreUserKnownHosts no
# Don't read the user's ~/.rhosts and ~/.shosts files
#IgnoreRhosts yes

# To disable tunneled clear text passwords, change to no here!
#PasswordAuthentication yes
#PermitEmptyPasswords no

#AllowAgentForwarding yes
#AllowTcpForwarding yes
#GatewayPorts no
#PermitTTY yes
#PrintMotd yes
#PrintLastLog yes
#TCPKeepAlive yes
#UseLogin no
#PermitUserEnvironment no
#ClientAliveInterval 0
#ClientAliveCountMax 3
#UseDNS no
#PidFile /var/run/sshd.pid
#MaxStartups 10:30:100
#PermitTunnel no
#ChrootDirectory none
#VersionAddendum none

# no default banner path
#Banner none

# override default of no subsystems
Subsystem   sftp    sftp-server.exe

# Example of overriding settings on a per-user basis
#Match User anoncvs
#   AllowTcpForwarding no
#   PermitTTY no
#   ForceCommand cvs server

Match Group administrators
       AuthorizedKeysFile __PROGRAMDATA__/ssh/administrators_authorized_keys

The latest builds of Windows 10 and Windows 11 include a build-in SSH server and client that are based on OpenSSH.
This means now you can remotely connect to Windows 10/11 or Windows Server 2019 using any SSH client, like Linux distros.
Let’s see how to configure OpenSSH on Windows 10 and Windows 11, and connect to it using Putty or any other SSH client.

OpenSSH is an open-source, cross-platform version of Secure Shell (SSH) that is used by Linux users for a long time.
This project is currently ported to Windows and can be used as an SSH server on almost any version of Windows.
In the latest versions of Windows Server 2022/2019 and Windows 11, OpenSSH is built-in to the operating system image.

How to install SSH Server on Windows 10?

Make sure our build of Windows 10 is 1809 or newer. The easiest way to do this is by running the command:

Note. If you have an older Windows 10 build installed, you can update it through Windows Update or using an ISO image with a newer version of Windows 10 (you can create an image using the Media Creation Tool). If you don’t want to update your Windows 10 build, you can manually install the Win32-OpenSSH port for Windows with GitHub.

Enable feature

We can enable OpenSSH server in Windows 10 through the graphical Settings panel:

1. Go to the Settings > Apps > Apps and features > Optional features (or run the command ms-settings:appsfeatures)
   

2. Click Add a feature, select OpenSSH Server (OpenSSH-based secure shell (SSH) server, for secure key management and access from remote machines), and click Install
   

Install using PowerShell

We can also install sshd server using PowerShell:

Add-WindowsCapability -Online -Name OpenSSH.Server*

Install using DISM

Or we can also install sshd server using DISM:

dism /Online /Add-Capability /CapabilityName:OpenSSH.Server~~~~0.0.1.0

If you want to make sure the OpenSSH server is installed, run the following PS command:

Get-WindowsCapability -Online | ? Name -like 'OpenSSH.Server*'

How to uninstall SSH Server?

Use the following PowerShell command to uninstall the SSH server:

Remove-WindowsCapability -Online -Name OpenSSH.Server~~~~0.0.1.0

How to Install SSH Server on Windows 11?

Also, you can add the OpenSSH Server on Windows 11.

1. Go to Settings > Apps > Optional features;
2. Click View Features;
   

Select OpenSSH Server from the list and click Next > Install;

Wait for the installation to complete.

The OpenSSH binaries are located in the C:\Windows\System32\OpenSSH\ folder.

Configuring SSH Service on Windows 10 and 11

Check the status of ssh-agent and sshd services using the PowerShell command Get-Service:

As we can see, both services are in a Stopped state and not added to the automatic startup list. To start services and configure autostart for them, run the following commands:

Start-Service sshd
Set-Service -Name sshd -StartupType 'Automatic'

Start-Service 'ssh-agent'
Set-Service -Name 'ssh-agent' -StartupType 'Automatic'

We also need to allow incoming connections to TCP port 22 in the Windows Defender Firewall. We can open the port using netsh:

netsh advfirewall firewall add rule name=”SSHD service” dir=in action=allow protocol=TCP localport=22

Or we can add a firewall rule to allow SSH traffic using PowerShell:

New-NetFirewallRule -Name sshd -DisplayName 'OpenSSH Server (sshd)' -Enabled True -Direction Inbound -Protocol TCP -Action Allow -LocalPort 22

Now we can connect to Windows 10 using any SSH client. To connect from Linux, use the command:

ssh -p 22 admin@192.168.1.90

Here, the admin is a local Windows user under which we want to connect. 192.168.1.90 is an IP address of your Windows 10 computer.

After that, a new Windows command prompt window will open in SSH session.

Hint. To run the PowerShell.exe cli instead of cmd.exe shell when logging in via SSH on Windows 10, we need to run the following command in Windows 10 (under admin account):

New-ItemProperty -Path "HKLM:\SOFTWARE\OpenSSH" -Name DefaultShell -Value "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -PropertyType String -Force

Now, we change the default OpenSSH shell. From here, when connecting to Windows via SSH, you will immediately see PowerShell prompt instead of cmd.exe.

If you want to use key-based ssh authentication instead of password authentication, you need to generate a key using ssh-keygen on your client.

Then, the contents of the id_rsa.pub file must be copied to the c:\users\admin\.ssh\authorized_keys file in Windows 10.

After that, you can connect from your Linux client to Windows 10 without a password. Use the command:

ssh -l admin@192.168.1.90

Configuration

We can configure various OpenSSH server settings in Windows using the %programdata%\ssh\sshd_config configuration file.

For example, we can disable password authentication and leave only key-based auth with:

PubkeyAuthentication yes
PasswordAuthentication no

Here we can also specify a new TCP port (instead of the default TCP 22 port) on which the SSHD will accept connections. For example:

Using the directives AllowGroups, AllowUsers, DenyGroups, DenyUsers, you can specify users and groups who are allowed or denied to connect to Windows via SSH:

• DenyUsers theitbros\jbrown@192.168.1.15 — blocks connections to username jbrown from 192.168.1.15 hostsж
• DenyUsers theitbros\* — prevent all users from theitbros domain to connect host using sshж
• AllowGroups theitbros\ssh_allow — only allow users from theitbtos\ssh_allow connect hostю
• The allow and deny rules of sshd are processed in the following order: DenyUsers, AllowUsers, DenyGroups, and AllowGroups.

After making changes to the sshd_config file, you need to restart the sshd service:

Get-Service sshd | Restart-Service –force

In previous versions of OpenSSH on Windows, all sshd service logs were written to the text file C:\ProgramData\ssh\logs\sshd.log by default.

On Windows 11, SSH logs can be viewed using the Event Viewer console (eventvwr.msc). All SSH events are available in a separate section Application and Services Logs > OpenSSH > Operational.

For example, the screenshot shows an example of an event with a successful connection to the computer via SSH. You can see the ssh client’s IP address (hostname) and the username used to connect.

sshd: Accepted password for jbrown from 192.168.14.14. port 49833 ssh2