Public/Get-SudoStatus.ps1

<#
    .SYNOPSIS
        Determines if the specified user has sudo privileges on a Remote Host, and if so, whether or not they are prompted for a
        sudo password when running 'sudo pwsh'.
 
        Returns a pscustomobject with bool properties 'HasSudoPrivileges' and 'PasswordPrompt'.
 
    .DESCRIPTION
        See SYNOPSIS
 
    .PARAMETER RemoteHostNameOrIP
        This parameter is MANDATORY.
 
        This parameter takes a string that represents the DNS-resolvable HostName/FQDN or IPv4 Address of the target Remote Host
 
    .PARAMETER LocalUserName
        This parameter is MANDATORY for the Parameter Set 'Local'.
 
        This parameter takes a string that represents the Local User Account on the Remote Host that you are using to ssh into
        the Remote Host. This string must be in format: <RemoteHostName>\<UserName>
 
    .Parameter DomainUserName
        This parameter is MANDATORY for the Parameter Set 'Domain'.
 
        This parameter takes a string that represents the Domain User Account on the Remote Host that you are using to ssh into
        the Remote Host. This string must be in format: <DomainShortName>\<UserName>
 
    .Parameter LocalPasswordSS
        This parameter is MANDATORY for the Parameter Set 'Local'.
 
        This parameter takes a securestring that represents the password for the -LocalUserName you are using to ssh into the
        Remote Host.
 
    .Parameter DomainPasswordSS
        This parameter is MANDATORY for the Parameter Set 'Domain'.
 
        This parameter takes a securestring that represents the password for the -DomainUserName you are using to ssh into the
        Remote Host.
 
    .PARAMETER KeyFilePath
        This parameter is OPTIONAL.
 
        This parameter takes a string that represents the full path to the Key File you are using to ssh into the Remote Host.
        Use this parameter instead of -LocalPasswordSS or -DomainPasswordSS.
 
    .EXAMPLE
        # Minimal parameters...
 
        $GetSudoStatusSplatParams = @{
            RemoteHostNameOrIP = "zerowin16sshb"
            DomainUserNameSS = "zero\zeroadmin"
            DomainPasswordSS = $(Read-Host -Prompt "Enter password" -AsSecureString)
        }
        Get-SudoStatus @GetSudoStatusSplatParams
 
    .EXAMPLE
        # Using a local account on the Remote Host...
 
        $GetSudoStatusSplatParams = @{
            RemoteHostNameOrIP = "centos7nodomain"
            LocalUserNameSS = "centos7nodomain\vagrant"
            LocalPasswordSS = $(Read-Host -Prompt "Enter password" -AsSecureString)
        }
        Get-SudoStatus @GetSudoStatusSplatParams
 
    .EXAMPLE
        # Using an ssh Key File instead of a password...
 
        $GetSudoStatusSplatParams = @{
            RemoteHostNameOrIP = "centos7nodomain"
            LocalUserNameSS = "centos7nodomain\vagrant"
            KeyFilePath = $HOME/.ssh/my_ssh_key
        }
        Get-SudoStatus @GetSudoStatusSplatParams
         
#>

function Get-SudoStatus {
    [CmdletBinding()]
    Param(
        [Parameter(Mandatory=$True)]
        [string]$RemoteHostNameOrIP,

        [Parameter(
            Mandatory=$True,
            ParameterSetName='Local'
        )]
        [ValidatePattern("\\")] # Must be in format <RemoteHostName>\<User>
        [string]$LocalUserName,

        [Parameter(
            Mandatory=$True,
            ParameterSetName='Domain'    
        )]
        [ValidatePattern("\\")] # Must be in format <DomainShortName>\<User>
        [string]$DomainUserName,

        [Parameter(
            Mandatory=$False,
            ParameterSetName='Local'    
        )]
        [securestring]$LocalPasswordSS,

        [Parameter(
            Mandatory=$False,
            ParameterSetName='Domain'
        )]
        [securestring]$DomainPasswordSS,

        [Parameter(Mandatory=$False)]
        [string]$KeyFilePath
    )

    #region >> Prep

    if (!$(Get-Command ssh -ErrorAction SilentlyContinue)) {
        Write-Error "Unable to find 'ssh'! Please make sure it is installed and part of your Environment/System Path! Halting!"
        $global:FunctionResult = "1"
        return
    }

    if ($KeyFilePath) {
        if (!$(Test-Path $KeyFilePath)) {
            Write-Error "Unable to find KeyFilePath '$KeyFilePath'! Halting!"
            $global:FunctionResult = "1"
            return
        }

        if (!$LocalUserName -and !$DomainUserName) {
            Write-Error "You must supply either -LocalUserName or -DomainUserName when using the -KeyFilePath parameter! Halting!"
            $global:FunctionResult = "1"
            return
        }
    }

    try {
        $RemoteHostNetworkInfo = ResolveHost -HostNameOrIP $RemoteHostNameOrIP -ErrorAction Stop
    }
    catch {
        Write-Error $_
        Write-Error "Unable to resolve '$RemoteHostNameOrIP'! Halting!"
        $global:FunctionResult = "1"
        return
    }

    if ($LocalPasswordSS -or $DomainPasswordSS -and $KeyFilePath) {
        Write-Error "Please use EITHER -KeyFilePath OR -LocalPasswordSS/-DomainPasswordSS in order to ssh to $RemoteHostNameOrIP! Halting!"
        $global:FunctionResult = "1"
        return
    }

    if ($LocalUserName) {
        if ($($LocalUserName -split "\\")[0] -ne $RemoteHostNetworkInfo.HostName) {
            $ErrMsg = "The HostName indicated by -LocalUserName (i.e. $($($LocalUserName -split "\\")[0]) is not the same as " +
            "the HostName as determined by network resolution (i.e. $($RemoteHostNetworkInfo.HostName))! Halting!"
            Write-Error $ErrMsg
            $global:FunctionResult = "1"
            return
        }
    }
    if ($DomainUserName) {
        if ($($DomainUserName -split "\\")[0] -ne $($RemoteHostNetworkInfo.Domain -split "\.")[0]) {
            $ErrMsg = "The Domain indicated by -DomainUserName (i.e. '$($($DomainUserName -split "\\")[0])') is not the same as " +
            "the Domain as determined by network resolution (i.e. '$($($RemoteHostNetworkInfo.Domain -split "\.")[0])')! Halting!"
            Write-Error $ErrMsg
            $global:FunctionResult = "1"
            return
        }
    }

    if (!$PSVersionTable.Platform -or $PSVersionTable.Platform -eq "Win32NT") {
        try {
            if ($(Get-Module -ListAvailable).Name -notcontains 'WinSSH') {$null = Install-Module WinSSH -ErrorAction Stop}
            if ($(Get-Module).Name -notcontains 'WinSSH') {$null = Import-Module WinSSH -ErrorAction Stop}
            Import-Module "$($(Get-Module WinSSH).ModuleBase)\Await\Await.psd1" -ErrorAction Stop
        }
        catch {
            Write-Error $_
            $global:FunctionResult = "1"
            return
        }

        try {
            $null = Stop-AwaitSession
        }
        catch {
            Write-Verbose $_.Exception.Message
        }
    }

    if ($PSVersionTable.Platform -eq "Unix") {
        # Determine if we have required Linux commands
        [System.Collections.ArrayList]$LinuxCommands = @(
            "echo"
            "expect"
        )
        [System.Collections.ArrayList]$CommandsNotPresent = @()
        foreach ($CommandName in $LinuxCommands) {
            $CommandCheckResult = command -v $CommandName
            if (!$CommandCheckResult) {
                $null = $CommandsNotPresent.Add($CommandName)
            }
        }

        if ($CommandsNotPresent.Count -gt 0) {
            [System.Collections.ArrayList]$FailedInstalls = @()
            if ($CommandsNotPresent -contains "echo") {
                try {
                    $null = InstallLinuxPackage -PossiblePackageNames "coreutils" -CommandName "echo"
                }
                catch {
                    $null = $FailedInstalls.Add("coreutils")
                }
            }
            if ($CommandsNotPresent -contains "expect") {
                try {
                    $null = InstallLinuxPackage -PossiblePackageNames "expect" -CommandName "expect"
                }
                catch {
                    $null = $FailedInstalls.Add("expect")
                }
            }
    
            if ($FailedInstalls.Count -gt 0) {
                Write-Error "The following Linux packages are required, but were not able to be installed:`n$($FailedInstalls -join "`n")`nHalting!"
                $global:FunctionResult = "1"
                return
            }
        }

        [System.Collections.ArrayList]$CommandsNotPresent = @()
        foreach ($CommandName in $LinuxCommands) {
            $CommandCheckResult = command -v $CommandName
            if (!$CommandCheckResult) {
                $null = $CommandsNotPresent.Add($CommandName)
            }
        }
    
        if ($CommandsNotPresent.Count -gt 0) {
            Write-Error "The following Linux commands are required, but not present on $env:ComputerName:`n$($CommandsNotPresent -join "`n")`nHalting!"
            $global:FunctionResult = "1"
            return
        }
    }

    if ($LocalPasswordSS) {
        $LocalPassword = [Runtime.InteropServices.Marshal]::PtrToStringAuto([Runtime.InteropServices.Marshal]::SecureStringToBSTR($LocalPasswordSS))
    }
    If ($DomainPasswordSS) {
        $DomainPassword = [Runtime.InteropServices.Marshal]::PtrToStringAuto([Runtime.InteropServices.Marshal]::SecureStringToBSTR($DomainPasswordSS))
    }

    if ($LocalUserName) {
        $FullUserName = $($LocalUserName -split "\\")[-1]
    }
    if ($DomainUserName) {
        $DomainNameShort = $($DomainUserName -split "\\")[0]
        $FullUserName = $($DomainUserName -split "\\")[-1]
    }

    $OnWindows = !$PSVersionTable.Platform -or $PSVersionTable.Platform -eq "Win32NT"

    #endregion >> Prep

    #region >> Main

    $PSVerTablePwshBytes = [System.Text.Encoding]::Unicode.GetBytes('$PSVersionTable')
    $EncodedCommand = [Convert]::ToBase64String($PSVerTablePwshBytes)

    [System.Collections.ArrayList]$CheckSudoStatusScript = @(
        'command -v pwsh >/dev/null && ' + $('prompt=$(sudo -n pwsh -EncodedCommand {0} 2>&1)' -f $EncodedCommand) + ' || ' + $('prompt=$(sudo -n bash -c {0} 2>&1)' -f "'echo bashSuccess'")
        $('if [ $? -eq 0 ]; then echo {0}; elif echo $prompt | grep -q {1}; then echo {2}; else echo {3}; fi' -f "'NoPasswordPrompt'","'^sudo'","'PasswordPrompt'","'NoSudoPrivileges'")
    )
    $null = $CheckSudoStatusScript.Add('echo checkSudoComplete')

    $SSHScriptBuilderSplatParams = @{
        RemoteHostNameOrIP  = $RemoteHostNameOrIP
    }
    if ($LocalUserName) {
        $SSHScriptBuilderSplatParams.Add('LocalUserName',$LocalUserName)
    }
    if ($DomainUserName) {
        $SSHScriptBuilderSplatParams.Add('DomainUserName',$DomainUserName)
    }
    if ($KeyFilePath) {
        $SSHScriptBuilderSplatParams.Add("KeyFilePath",$KeyFilePath)
    }
    if ($LocalPassword) {
        $SSHScriptBuilderSplatParams.Add("LocalPassword",$LocalPassword)
    }
    if ($DomainPassword) {
        $SSHScriptBuilderSplatParams.Add("DomainPassword",$DomainPassword)
    }
    
    if ($OnWindows) {
        $SSHScriptBuilderSplatParams.Add('WindowsWaitTimeMin',[float]'.25')
    }
        
    $SSHScriptBuilderSplatParams.Add('SSHScriptArray',$CheckSudoStatusScript)

    $Output = SSHScriptBuilder @SSHScriptBuilderSplatParams
    
    if ($Output.AllOutput -match 'NoPasswordPrompt') {
        [pscustomobject]@{
            HasSudoPrivileges   = $True
            PasswordPrompt      = $False
            AllOutput           = $Output.AllOutput
        }
    }
    elseif ($Output.AllOutput -match 'PasswordPrompt') {
        [pscustomobject]@{
            HasSudoPrivileges   = $True
            PasswordPrompt      = $True
            AllOutput           = $Output.AllOutput
        }
    }
    elseif ($Output.AllOutput -match 'NoSudoPrivileges') {
        [pscustomobject]@{
            HasSudoPrivileges   = $False
            PasswordPrompt      = $False
            AllOutput           = $Output.AllOutput
        }
    }

    #endregion >> Main
}