Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Make sudo.ps1 support multi-line commands #39

Open
wants to merge 4 commits into
base: main
Choose a base branch
from
Open
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
135 changes: 71 additions & 64 deletions scripts/sudo.ps1
Original file line number Diff line number Diff line change
@@ -1,87 +1,94 @@
<#
.SYNOPSIS
Runs a scriptblock, command or application as an elevated process using sudo.exe
.DESCRIPTION
Wraps sudo.exe to add functionality for running PowerShell scripts or commands in an elevated process.

When running a scriptblock or PowerShell command, a new copy of PowerShell is run with sudo and an EncodedCommand.
When running a native application, the command itself is run with sudo.

This script DOES NOT (currently) support piping input to the elevated command.
#>

# Copyright (c) Microsoft Corporation.
# Licensed under the MIT License.
[CmdletBinding(DefaultParameterSetName = "Script")]
param(
# A scriptblock to run in an elevated process
[Parameter(Mandatory, Position = 0, ParameterSetName = "Script")]
[scriptblock]$ScriptBlock,

# open question - Should -NoProfile be used when invoking PowerShell
BEGIN {
if ($__SUDO_TEST -ne $true) {
$SUDOEXE = "sudo.exe"
}
else {
if ($null -eq $SUDOEXE) {
throw "variable SUDOEXE has not been set for testing"
}
}
# Run PowerShell with the -NoProfile switch
[switch]$NoProfile,

if ([Environment]::OSVersion.Platform -ne "Win32NT") {
# A command or application to run in an elevated process
[Parameter(Mandatory, Position = 0, ParameterSetName = "Command")]
[string]$Command,

# Arguments to pass to the command or application
[Parameter(Position = 1, ParameterSetName = "Command", ValueFromRemainingArguments)]
[Alias("Args")]
[PSObject[]]$ArgumentList
)
begin {
if ($IsLinux -or $IsMacOS) {
throw "This script works only on Microsoft Windows"
}

if ($null -eq (Get-Command -Type Application -Name "$SUDOEXE" -ErrorAction Ignore)) {
throw "'$SUDOEXE' cannot be found."
if ($__SUDO_TEST -ne $true) {
$Env:SUDOEXE = "sudo.exe"
Copy link
Author

@Jaykul Jaykul Feb 13, 2024

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This seems overly complicated. One must set two variables: SUDOEXE and __SUDO_TEST, to actually be able to use an alternate executable for testing? I'm not sure why this was here...

I would prefer to just have a parameter SudoPath that you can set to whatever you want for testing purposes, but that defaults to just sudo.exe and assumes that sudo.exe is in the PATH.

NOTE: I changed SUDOEXE to an environment variable. I feel like if we're using a mock sudo, you need to be able to set the environment stuff once (i.e. in your pipeline, or in your machine scope), instead of needing to set multiple flags for different wrapper scripts.

I'd rather remove these, but if we want to keep them, should __SUDO_TEST also be an environment variable?

} elseif (!$Env:SUDOEXE) {
throw "Environment variable SUDOEXE has not been set for testing"
}

$psProcess = Get-Process -id $PID
if (($null -eq $psProcess) -or ($psProcess.Count -ne 1)) {
throw "Cannot retrieve process for '$PID'"
if (!(Get-Command -Type Application -Name $Env:SUDOEXE -ErrorAction Ignore)) {
throw "Env:SUDOEXE is set to '$Env:SUDOEXE' but it cannot be found."

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Suggested change
throw "Env:SUDOEXE is set to '$Env:SUDOEXE' but it cannot be found."
throw "Env:SUDOEXE is set to '$Env:SUDOEXE' but cannot be found."

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

maybe "that cannot be found." or keep "it"

Copy link
Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Yeah, I think this:
"Env:SUDOEXE is set to 'C:\Windows\Sudo.exe' but it cannot be found"

Is better than:
"Env:SUDOEXE is set to 'C:\Windows\Sudo.exe' but cannot be found"

}

$thisPowerShell = $psProcess.MainModule.FileName
if ($null -eq $thisPowerShell) {
throw "Cannot determine path to '$psProcess'"
$thisPowerShell = (Get-Process -Id $PID).MainModule.FileName
Copy link
Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I want to point out that I dramatically simplified this, just because there isn't really any way this can go wrong. $PID is a constant in PowerShell and can't changed, so this is always going to return the full path to the executable.

if (!$thisPowerShell) {
throw "Cannot determine PowerShell executable path."
}

function convertToBase64EncodedString([string]$cmdLine) {
$bytes = [System.Text.Encoding]::Unicode.GetBytes($cmdLine)
function ConvertToBase64EncodedString([string]$InputObject) {
$bytes = [System.Text.Encoding]::Unicode.GetBytes($InputObject)
[Convert]::ToBase64String($bytes)
}

$MI = $MyInvocation
}

END {
$cmdArguments = $args

# short-circuit if the user provided a scriptblock, then we will use it and ignore any other arguments
if ($cmdArguments.Count -eq 1 -and $cmdArguments[0] -is [scriptblock]) {
$scriptBlock = $cmdArguments[0]
$encodedCommand = convertToBase64EncodedString -cmdLine ($scriptBlock.ToString())
if (($psversiontable.psversion.major -eq 7) -and ($__SUDO_DEBUG -eq $true)) {
Trace-Command -PSHOST -name param* -Expression { & $SUDOEXE "$thisPowerShell" -e $encodedCommand }
}
else {
& $SUDOEXE "$thisPowerShell" -e $encodedCommand
end {
# If the first parameter is the name of an executable, just run that without PowerShell
if ($PSCmdlet.ParameterSetName -eq "Command") {
if (@(Get-Command $Command -ErrorAction Ignore)[0].CommandType -eq "Application") {
# NOTE: this assumes that all the parameters can be just strings
if ($PSBoundParameters.Contains("Debug")) {
Copy link

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

this should be ContainsKey

Trace-Command -PSHost -Name param* -Expression { & $Env:SUDOEXE $Command @ArgumentList }
} else {
& $Env:SUDOEXE $Command $ArgumentList
}
return
} else {
# In this case, we're going to need to _make_ a scriptblock out of $MyInvocation.Statement
# NOT $MyInvocation.Line because there might be more than one line in the statement
# IISReset and Jaykul apologize for the reflection, but we need to support old versions of PowerShell
$Statement = [System.Management.Automation.InvocationInfo].GetMember(
'_scriptPosition',
[System.Reflection.BindingFlags]'NonPublic,Instance'
)[0].GetValue($MyInvocation).Text.
Comment on lines +74 to +77
Copy link

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

the trailing . after Text needs to be removed

# Strip the 'sudo' or 'sudo.ps1` or whatever off the front of the statement
$Statement = $Statement.SubString($MyInvocation.InvocationName.Length).Trim()
$EncodedCommand = ConvertToBase64EncodedString $Statement
}
return
} else {
$EncodedCommand = ConvertToBase64EncodedString $scriptBlock
}

$cmdLine = $MI.Line
$sudoOffset = $cmdLine.IndexOf($MI.InvocationName)
$cmdLineWithoutScript = $cmdLine.SubString($sudoOffset + 5)
$cmdLineAst = [System.Management.Automation.Language.Parser]::ParseInput($cmdLineWithoutScript, [ref]$null, [ref]$null)
$commandAst = $cmdLineAst.Find({$args[0] -is [System.Management.Automation.Language.CommandAst]}, $false)
$commandName = $commandAst.GetCommandName()
$isApplication = Get-Command -Type Application -Name $commandName -ErrorAction Ignore | Select-Object -First 1
$isCmdletOrScript = Get-Command -Type Cmdlet,ExternalScript -Name $commandName -ErrorAction Ignore | Select-Object -First 1
$switches = @("-NoLogo", "-NonInteractive")
if ($NoProfile) { $switches += "-NoProfile" }

# if the command is a native command, just invoke it
if ($null -ne $isApplication) {
if (($psversiontable.psversion.major -eq 7) -and ($__SUDO_DEBUG -eq $true)) {
trace-command -PSHOST -name param* -Expression { & $SUDOEXE $cmdArguments }
}
else {
& $SUDOEXE $cmdArguments
}
}
elseif ($null -ne $isCmdletOrScript) {
$encodedCommand = convertToBase64EncodedString($cmdLineWithoutScript)
if (($psversiontable.psversion.major -eq 7) -and ($__SUDO_DEBUG -eq $true)) {
trace-command -PSHOST -name param* -Expression { & $SUDOEXE -nologo -e $encodedCommand }
}
else {
& $SUDOEXE $thisPowerShell -nologo -e $encodedCommand
}
}
else {
throw "Cannot find '$commandName'"
if ($PSBoundParameters.Contains("Debug")) {
Copy link

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

this should also be ContainsKey

Trace-Command -PSHost -Name param* -Expression { & $Env:SUDOEXE $ThisPowerShell @switches -EncodedCommand $encodedCommand }
} else {
& $Env:SUDOEXE $ThisPowerShell @switches -EncodedCommand $encodedCommand
}
}