Public/New-SSHDServer.ps1
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<#
.SYNOPSIS This function installs and configures the SSHD server (sshd service) on the local host. .DESCRIPTION See .SYNOPSIS .NOTES .PARAMETER RemoveHostPrivateKeys This parameter is OPTIONAL. This parameter is a switch. Use it to add the Host Private Keys to the ssh-agent and remove the Private Key files frome the filesystem during sshd setup/config. Default is NOT to remove the Host Private Keys. .PARAMETER DefaultShell This parameter is OPTIONAL. This parameter takes a string that must be one of two values: "powershell","pwsh" If set to "powershell", when a Remote User connects to the local host via ssh, they will enter a Windows PowerShell 5.1 shell. If set to "pwsh", when a Remote User connects to the local host via ssh, the will enter a PowerShell Core 6 shell. If this parameter is NOT used, the Default shell will be cmd.exe. .PARAMETER SkipWinCapabilityAttempt This parameter is OPTIONAL. This parameter is a switch. In more recent versions of Windows (Spring 2018), OpenSSH Client and SSHD Server can be installed as Windows Features using the Dism Module 'Add-WindowsCapability' cmdlet. If you run this function on a more recent version of Windows, it will attempt to use 'Add-WindowsCapability' UNLESS you use this switch. As of May 2018, there are reliability issues with the 'Add-WindowsCapability' cmdlet. Using this switch is highly recommend in order to avoid using 'Add-WindowsCapability'. .EXAMPLE # Open an elevated PowerShell Session, import the module, and - PS C:\Users\zeroadmin> New-SSHDServer -DefaultShell powershell #> function New-SSHDServer { [CmdletBinding()] Param( [Parameter(Mandatory=$False)] [switch]$RemoveHostPrivateKeys, [Parameter(Mandatory=$False)] [ValidateSet("powershell","pwsh")] [string]$DefaultShell, [Parameter(Mandatory=$False)] [switch]$SkipWinCapabilityAttempt ) #region >> Prep if (!$(GetElevation)) { Write-Verbose "You must run PowerShell as Administrator before using this function! Halting!" Write-Error "You must run PowerShell as Administrator before using this function! Halting!" $global:FunctionResult = "1" return } $tempfile = [IO.Path]::Combine([IO.Path]::GetTempPath(), [IO.Path]::GetRandomFileName()) $OpenSSHWinPath = Join-Path $env:ProgramFiles "OpenSSH-Win64" $sshagentpath = Join-Path $OpenSSHWinPath "ssh-agent.exe" $sshdpath = Join-Path $OpenSSHWinPath "sshd.exe" $sshdir = Join-Path $env:ProgramData "ssh" $sshdConfigPath = Join-Path $sshdir "sshd_config" $logsdir = Join-Path $sshdir "logs" # Make sure $OpenSSHWinPath is part of $env:Path [System.Collections.Arraylist][array]$CurrentEnvPathArray = $env:Path -split ";" | Where-Object {![System.String]::IsNullOrWhiteSpace($_)} if ($CurrentEnvPathArray -notcontains $OpenSSHWinPath) { $CurrentEnvPathArray.Insert(0,$OpenSSHWinPath) $env:Path = $CurrentEnvPathArray -join ";" } # Make sure the dependency ssh-agent service is already installed if (![bool]$(Get-Service ssh-agent -ErrorAction SilentlyContinue)) { try { $InstallSSHAgentSplatParams = @{ ErrorAction = "SilentlyContinue" ErrorVariable = "ISAErr" } if ($SkipWinCapabilityAttempt) { $InstallSSHAgentSplatParams.Add("SkipWinCapabilityAttempt",$True) } if ($Force) { $InstallSSHAgentSplatParams.Add("Force",$True) } $InstallSSHAgentResult = Install-SSHAgentService @InstallSSHAgentSplatParams if (!$InstallSSHAgentResult) {throw "The Install-SSHAgentService function failed!"} } catch { Write-Error $_ Write-Host "Errors for the Install-SSHAgentService function are as follows:" Write-Error $($ISAErr | Out-String) $global:FunctionResult = "1" return } } if (!$(Test-Path $OpenSSHWinPath)) { Write-Error "The path $OpenSSHWinPath does not exist! Halting!" $global:FunctionResult = "1" return } #endregion >> Prep #region >> Install the sshd Service if ([Environment]::OSVersion.Version -ge [version]"10.0.17063" -and !$SkipWinCapabilityAttempt) { try { # Import the Dism Module if ($(Get-Module).Name -notcontains "Dism") { try { Import-Module Dism } catch { # Using full path to Dism Module Manifest because sometimes there are issues with just 'Import-Module Dism' $DismModuleManifestPaths = $(Get-Module -ListAvailable -Name Dism).Path foreach ($MMPath in $DismModuleManifestPaths) { try { Import-Module $MMPath -ErrorAction Stop break } catch { Write-Verbose "Unable to import $MMPath..." } } } } if ($(Get-Module).Name -notcontains "Dism") { Write-Error "Problem importing the Dism PowerShell Module! Unable to proceed with Hyper-V install! Halting!" $global:FunctionResult = "1" return } $SSHDServerFeature = Get-WindowsCapability -Online | Where-Object {$_.Name -match 'OpenSSH\.Server'} if (!$SSHDServerFeature) { Write-Warning "Unable to find the OpenSSH.Server feature using the Get-WindowsCapability cmdlet!" $AddWindowsCapabilityFailure = $True } else { try { $SSHDFeatureInstall = Add-WindowsCapability -Online -Name $SSHDServerFeature.Name -ErrorAction Stop } catch { Write-Warning "The Add-WindowsCapability cmdlet failed to add the $($SSHDServerFeature.Name)!" $AddWindowsCapabilityFailure = $True } } # Make sure the sshd service exists try { $SSHDServiceCheck = Get-Service sshd -ErrorAction Stop } catch { $AddWindowsCapabilityFailure = $True } } catch { Write-Warning "The Add-WindowsCapability cmdlet failed to add feature: $($SSHDServerFeature.Name) !" $AddWindowsCapabilityFailure = $True } if (!$AddWindowsCapabilityFailure) { try { # NOTE: $sshdir won't actually be created until you start the SSHD Service for the first time # Starting the service also creates all of the needed host keys. $SSHDServiceInfo = Get-Service sshd -ErrorAction Stop if ($SSHDServiceInfo.Status -ne "Running") { $SSHDServiceInfo | Start-Service -ErrorAction Stop } if (Test-Path "$env:ProgramFiles\OpenSSH-Win64\sshd_config_default") { # Copy sshd_config_default to $sshdir\sshd_config $sshddefaultconfigpath = Join-Path $OpenSSHWinPath "sshd_config_default" if (-not (Test-Path $sshdconfigpath -PathType Leaf)) { $null = Copy-Item $sshddefaultconfigpath -Destination $sshdconfigpath -Force -ErrorAction Stop } } else { $SSHConfigUri = "https://raw.githubusercontent.com/PowerShell/Win32-OpenSSH/L1-Prod/contrib/win32/openssh/sshd_config" Invoke-WebRequest -Uri $SSHConfigUri -OutFile $sshdConfigPath } $PubPrivKeyPairFiles = Get-ChildItem -Path $sshdir -File | Where-Object {$_.Name -match "ssh_host_rsa"} $PubHostKey = $PubPrivKeyPairFiles | Where-Object {$_.Extension -eq ".pub"} $PrivHostKey = $PubPrivKeyPairFiles | Where-Object {$_.Extension -ne ".pub"} } catch { Write-Error $_ $global:FunctionResult = "1" return } } } if ([Environment]::OSVersion.Version -lt [version]"10.0.17063" -or $AddWindowsCapabilityFailure -or $SkipWinCapabilityAttempt) { if (!$(Test-Path $sshdpath)) { Write-Error "The path $sshdpath does not exist! Halting!" $global:FunctionResult = "1" return } # NOTE: Starting the sshd Service should create all below content and set appropriate permissions <# try { # Create the C:\ProgramData\ssh folder and set its permissions if (-not (Test-Path $sshdir -PathType Container)) { $null = New-Item $sshdir -ItemType Directory -Force -ErrorAction Stop } # Set Permissions $SecurityDescriptor = Get-NTFSSecurityDescriptor -Path $sshdir $SecurityDescriptor | Disable-NTFSAccessInheritance -RemoveInheritedAccessRules $SecurityDescriptor | Clear-NTFSAccess $SecurityDescriptor | Add-NTFSAccess -Account "NT AUTHORITY\Authenticated Users" -AccessRights "ReadAndExecute, Synchronize" -AppliesTo ThisFolderSubfoldersAndFiles $SecurityDescriptor | Add-NTFSAccess -Account SYSTEM -AccessRights FullControl -AppliesTo ThisFolderSubfoldersAndFiles $SecurityDescriptor | Add-NTFSAccess -Account Administrators -AccessRights FullControl -AppliesTo ThisFolderSubfoldersAndFiles $SecurityDescriptor | Set-NTFSSecurityDescriptor Set-NTFSOwner -Path $sshdir -Account Administrators } catch { Write-Error $_ $global:FunctionResult = "1" return } try { # Create logs folder and set its permissions if (-not (Test-Path $logsdir -PathType Container)) { $null = New-Item $logsdir -ItemType Directory -Force -ErrorAction Stop } # Set Permissions $SecurityDescriptor = Get-NTFSSecurityDescriptor -Path $logsdir $SecurityDescriptor | Disable-NTFSAccessInheritance -RemoveInheritedAccessRules $SecurityDescriptor | Clear-NTFSAccess #$SecurityDescriptor | Add-NTFSAccess -Account "NT AUTHORITY\Authenticated Users" -AccessRights "ReadAndExecute, Synchronize" -AppliesTo ThisFolderSubfoldersAndFiles $SecurityDescriptor | Add-NTFSAccess -Account SYSTEM -AccessRights FullControl -AppliesTo ThisFolderSubfoldersAndFiles $SecurityDescriptor | Add-NTFSAccess -Account Administrators -AccessRights FullControl -AppliesTo ThisFolderSubfoldersAndFiles $SecurityDescriptor | Set-NTFSSecurityDescriptor Set-NTFSOwner -Path $logsdir -Account Administrators } catch { Write-Error $_ $global:FunctionResult = "1" return } try { # Copy sshd_config_default to $sshdir\sshd_config $sshdConfigPath = Join-Path $sshdir "sshd_config" $sshddefaultconfigpath = Join-Path $OpenSSHWinPath "sshd_config_default" if (-not (Test-Path $sshdconfigpath -PathType Leaf)) { $null = Copy-Item $sshddefaultconfigpath -Destination $sshdconfigpath -Force -ErrorAction Stop } } catch { Write-Error $_ $global:FunctionResult = "1" return } #> try { if (Get-Service sshd -ErrorAction SilentlyContinue) { Stop-Service sshd $null = sc.exe delete sshd } $sshdDesc = "SSH protocol based service to provide secure encrypted communications between two untrusted hosts over an insecure network." $null = New-Service -Name sshd -DisplayName "OpenSSH SSH Server" -BinaryPathName $sshdpath -Description $sshdDesc -StartupType Automatic $null = sc.exe privs sshd SeAssignPrimaryTokenPrivilege/SeTcbPrivilege/SeBackupPrivilege/SeRestorePrivilege/SeImpersonatePrivilege } catch { Write-Error $_ $global:FunctionResult = "1" return } $SSHDServiceInfo = Get-Service sshd -ErrorAction Stop if ($SSHDServiceInfo.Status -ne "Running") { $SSHDServiceInfo | Start-Service -ErrorAction Stop } Start-Sleep -Seconds 5 if ($(Get-Service sshd).Status -ne "Running") { Write-Error "The sshd service did not start succesfully (within 5 seconds) after initial install! Please check your sshd_config configuration. Halting!" $global:FunctionResult = "1" return } # NOTE: Starting the sshd Service should create the host keys, so we don't need to do it here <# # Setup Host Keys $SSHKeyGenProcessInfo = New-Object System.Diagnostics.ProcessStartInfo $SSHKeyGenProcessInfo.WorkingDirectory = $sshdir $SSHKeyGenProcessInfo.FileName = "ssh-keygen.exe" $SSHKeyGenProcessInfo.RedirectStandardError = $true $SSHKeyGenProcessInfo.RedirectStandardOutput = $true $SSHKeyGenProcessInfo.UseShellExecute = $false $SSHKeyGenProcessInfo.Arguments = "-A" $SSHKeyGenProcess = New-Object System.Diagnostics.Process $SSHKeyGenProcess.StartInfo = $SSHKeyGenProcessInfo $SSHKeyGenProcess.Start() | Out-Null $SSHKeyGenProcess.WaitForExit() $SSHKeyGenStdout = $SSHKeyGenProcess.StandardOutput.ReadToEnd() $SSHKeyGenStderr = $SSHKeyGenProcess.StandardError.ReadToEnd() $SSHKeyGenAllOutput = $SSHKeyGenStdout + $SSHKeyGenStderr if ($SSHKeyGenAllOutput -match "fail|error") { Write-Error $SSHKeyGenAllOutput Write-Error "The 'ssh-keygen -A' command failed! Halting!" $global:FunctionResult = "1" return } #> # Add the ssh_host_rsa private key to the ssh-agent $PubPrivKeyPairFiles = Get-ChildItem -Path $sshdir -File | Where-Object {$_.Name -match "ssh_host_rsa"} $PubHostKey = $PubPrivKeyPairFiles | Where-Object {$_.Extension -eq ".pub"} $PrivHostKey = $PubPrivKeyPairFiles | Where-Object {$_.Extension -ne ".pub"} if ($(Get-Service ssh-agent).Status -ne "Running") { Start-Service ssh-agent Start-Sleep -Seconds 5 } if ($(Get-Service "ssh-agent").Status -ne "Running") { Write-Error "The ssh-agent service did not start succesfully (within 5 seconds)! Please check your config! Halting!" $global:FunctionResult = "1" return } if (![bool]$(Get-Command ssh-add -ErrorAction SilentlyContinue)) { Write-Error 'Unable to find ssh-add.exe! Is it part of your $env:Path? Halting!' $global:FunctionResult = "1" return } $SSHAddProcessInfo = New-Object System.Diagnostics.ProcessStartInfo $SSHAddProcessInfo.WorkingDirectory = $sshdir $SSHAddProcessInfo.FileName = "ssh-add.exe" $SSHAddProcessInfo.RedirectStandardError = $true $SSHAddProcessInfo.RedirectStandardOutput = $true $SSHAddProcessInfo.UseShellExecute = $false $SSHAddProcessInfo.Arguments = "$($PrivHostKey.FullName)" $SSHAddProcess = New-Object System.Diagnostics.Process $SSHAddProcess.StartInfo = $SSHAddProcessInfo $SSHAddProcess.Start() | Out-Null $SSHAddProcess.WaitForExit() $SSHAddStdout = $SSHAddProcess.StandardOutput.ReadToEnd() $SSHAddStderr = $SSHAddProcess.StandardError.ReadToEnd() $SSHAddAllOutput = $SSHAddStdout + $SSHAddStderr if ($SSHAddAllOutput -match "fail|error") { Write-Error $SSHAddAllOutput Write-Error "The 'ssh-add $($PrivKey.FullName)' command failed!" } else { if ($RemoveHostPrivateKeys) { Remove-Item $PrivKey } } # EDIT: The below shouldn't be necessary... # IMPORTANT: It is important that File Permissions are "Fixed" at the end (as opposed to earlier in this function), # otherwise previous steps break <# if (!$(Test-Path "$OpenSSHWinPath\FixHostFilePermissions.ps1")) { Write-Error "The script $OpenSSHWinPath\FixHostFilePermissions.ps1 cannot be found! Permissions in the $OpenSSHWinPath directory need to be fixed before the sshd service will start successfully! Halting!" $global:FunctionResult = "1" return } try { & "$OpenSSHWinPath\FixHostFilePermissions.ps1" -Confirm:$false } catch { Write-Error "The script $OpenSSHWinPath\FixHostFilePermissions.ps1 failed! Permissions in the $OpenSSHWinPath directory need to be fixed before the sshd service will start successfully! Halting!" $global:FunctionResult = "1" return } #> } # Set the default shell if ($DefaultShell -eq "powershell" -or !$DefaultShell) { $null = Set-DefaultShell -DefaultShell "powershell" } else { $null = Set-DefaultShell -DefaultShell "pwsh" } #endregion >> Install the sshd Service ##### BEGIN Main Body ##### # Make sure port 22 is open if (!$(TestPort -Port 22).Open) { # See if there's an existing rule regarding locahost TCP port 22, if so change it to allow port 22, if not, make a new rule $Existing22RuleCheck = Get-NetFirewallPortFilter -Protocol TCP | Where-Object {$_.LocalPort -eq 22} if ($Existing22RuleCheck -ne $null) { $Existing22Rule = Get-NetFirewallRule -AssociatedNetFirewallPortFilter $Existing22RuleCheck | Where-Object {$_.Direction -eq "Inbound"} if ($Existing22Rule -ne $null) { $null = Set-NetFirewallRule -InputObject $Existing22Rule -Enabled True -Action Allow } else { $ExistingRuleFound = $False } } if ($Existing22RuleCheck -eq $null -or $ExistingRuleFound -eq $False) { $null = New-NetFirewallRule -Action Allow -Direction Inbound -Name ssh -DisplayName ssh -Enabled True -LocalPort 22 -Protocol TCP } } Restart-Service sshd Start-Sleep -Seconds 5 if ($(Get-Service sshd).Status -ne "Running") { Write-Error "The sshd service did not start succesfully (within 5 seconds)! Please check your sshd_config configuration. Halting!" $global:FunctionResult = "1" return } if ($DefaultShell) { # For some reason, the 'ForceCommand' option is not picked up the first time the sshd service is started # so restart sshd service Restart-Service sshd Start-Sleep -Seconds 5 } if ($(Get-Service sshd).Status -ne "Running") { Write-Error "The sshd service did not start succesfully (within 5 seconds)! Please check your sshd_config configuration. Halting!" $global:FunctionResult = "1" return } else { Write-Host "The sshd service was successfully installed and started!" -ForegroundColor Green } [pscustomobject]@{ SSHDServiceStatus = $(Get-Service sshd).Status SSHAgentServiceStatus = $(Get-Service ssh-agent).Status RSAHostPublicKey = $PubHostKey RSAHostPrivateKey = $PrivHostKey } } |