SecretManagement.LastPass

0.2.1

SecretManagement.LastPass.Extension/SecretManagement.LastPass.Extension.psm1

# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License.
using namespace Microsoft.PowerShell.SecretManagement

#region constants

# The capture groups are:
# 1. The date and time that the secret was stored
# 2. The ls short output (just the name & id)
# 3. The name of the secret
# 4. The username of the secret
$lsLongOutput = "(\d\d\d\d-\d\d-\d\d \d\d:\d\d)? *((.*) \[id: \d*\]) \[username: (.*)\]"

# Custom notes in lpass CLI are a bit of a mess.
# For default types
# Get operation will return the value
# Set operation will only accept the key
# This is to convert value obtained from Get when doing a Set.
$DefaultNoteTypeMap = @{
    'Address'           = 'address'
    # 'amex' = '' # Possibly deprecated
    'Bank Account'      = 'bank'
    'Credit Card'       = 'credit-card'
    'Database'          = 'database'
    "Driver's License"  = 'drivers-license'
    'Email Account'     = 'email'
    'Health Insurance'  = 'health-insurance'
    'Instant Messenger' = 'im'
    'Insurance'         = 'insurance'
    #'mastercard' = '' # Possibly deprecated
    'Membership'        = 'membership'
    'Passport'          = 'passport'
    'Server'            = 'server'
    'Software License'  = 'software-license'
    'SSH Key'           = 'ssh-key'
    'Social Security'   = 'ssn'
    #'visa' = '' # Possibly deprecated
    'Wi-Fi Password'    = 'wifi'
} 

$lpassMessage = @{
    AccountNotFound = 'Error: Could not find specified account(s).'
    # Need to use wildcard since the path of lpass could be different
    LoggedOut = 'Error: Could not find decryption key. Perhaps you need to login with*'
    MultipleMatches = 'Multiple matches found.'
}

# These fields need special consideration when working with secrets.
# Language / NoteType are fields that are part of any custom notes and always appear last (before Notes)
#Notes field can appear in any secrets and is always the last field. It is also the only multiline field.
$SpecialKeys = @('Language', 'NoteType', 'Notes')

#endregion

# Internal wrapper around the actual call. Reserved for Invoke-lpass. Use Invoke-lpass instead.
function Invoke-lpassInternal {
    [CmdletBinding()]
    Param(
        [Parameter(ValueFromPipeline)]
        [object]$InputObject,
        [Switch]$UseNative,
        [String]$lpassPath,
        [string[]]$Arguments
    )

    if ($UseNative) {
        if ($InputObject) { return $InputObject | & $lpassPath @Arguments }
        return & $lpassPath @Arguments
    }
    # WSL
    if ($InputObject) { return $InputObject | & wsl $lpassPath @Arguments }
    return & wsl $lpassPath @Arguments
}


<#
.SYNOPSIS
Manage calls to lastpass.

.DESCRIPTION
Manage calls to lastpass. show & login command are special and requires us to not redirect streams
to get the prompt. Everything else have its error stream redirect to success (2>&1)

.PARAMETER Arguments
Arguments to pass to lpass CLI

.PARAMETER InputObject
Used by some of the non-interactive commands such as lpass add / lpass edit

.PARAMETER VaultParams
This should never be populated from the extension. It is only for the main module, which have
no awareness of the vault parameters and need to have them fed to it. If this parameter is provided,
it overrides $AdditionalParameters
#>
function Invoke-lpass {
    [CmdletBinding()]
    param (
        [Parameter()]
        [string[]]$Arguments,
        [Parameter(ValueFromPipeline)]
        [object]$InputObject,
        #Only for root module functions
        [hashtable]$VaultParams
    )
     # Command from the root module do not contain $AdditionalParameters
    if ($null -ne $VaultParams) { $AdditionalParameters = $VaultParams }
    
    $UseWSL = $AdditionalParameters.wsl -eq $true
    $lpassPath = if ($null -ne $AdditionalParameters.lpassPath) { "`"$($AdditionalParameters.lpassPath)`"" } else { 'lpass' }
    $UseNative = -not $UseWSL

    if (($UseNative -and -not (Get-Command $lpassPath -EA 0)) -or 
        ($UseWSL -and (& wsl $lpassPath --version ) -notlike 'LastPass CLI*')) {
        throw "lpass executable not found or installed."
    }

    $Params = @{
        InputObject = $InputObject
        UseNative   = $UseNative
        lpassPath   = $lpassPath
        Arguments   = $Arguments
    }

    # If we do redirect on the command themselves, it doesn't work.
    # Doing redirect on the commands wrapped in a function work.
    
    if ($Arguments.Count -gt 0) {
        switch ($Arguments[0]) {
            'login' {  
                # We want the prompt always, so no redirect
                $result = Invoke-lpassInternal @Params
            }
            {$_ -in 'show','ls','rm'} {
                # We might want the prompt, but are not sure yet.
                $result = Invoke-lpassInternal @Params 2>&1
                # If we get the message stating we might be logged out, we reissue the command without redirect (for Prompt)
                if ($result -is [System.Management.Automation.ErrorRecord] -and [String]$result -like $lpassMessage.LoggedOut) {
                    $result2 = Invoke-lpassInternal @Params
                    # If $result2 -eq $null, something will have been printed in the console (because we disabled the redirect)
                    # We therefore want to keep the original $result "Logged out" so it is thrown later on
                    # If not $null, we want to evaluate $result2 instead and discard $result
                    if ($null -ne $result2 -or $Arguments[0] -eq 'rm') { $result = $result2 }
                }
            }
            Default {
                # By default, we always redirect streams
                $result = Invoke-lpassInternal @Params 2>&1
            }
        }
    }

    if ($result -is [System.Management.Automation.ErrorRecord]) {
        switch -Wildcard ([string] $result) {
            $lpassMessage.LoggedOut { throw [PasswordRequiredException] "$($lpassMessage.LoggedOut.TrimEnd("*")) Connect-LastPass" }
            $lpassMessage.AccountNotFound { break }
            $lpassMessage.MultipleMatches { break }
            # We leave handling exceptions to SecretManagement
            default {
                # We do a Write-Error so it's more discoverable to the user
                # (but it will exist in the inner exception of the throw)
                Write-Error -ErrorRecord $result
                throw $result
            }
        }
    }

    # This should be a string or a collection of strings
    return $result
}

function Get-Secret
{
    [CmdletBinding()]
    param (
        [Parameter(ValueFromPipelineByPropertyName)]
        [string] $Name,
        [Parameter(ValueFromPipelineByPropertyName)]
        [string] $VaultName,
        [Parameter(ValueFromPipelineByPropertyName)]
        [hashtable] $AdditionalParameters
    )

    # TODO error handling

    if ($AdditionalParameters.Verbose) {
        $VerbosePreference = "Continue"
    }

    if ($Name -match ".* \(id: (\d*)\)") {
        $Name = $Matches[1]
    }

    $res = Invoke-lpass 'show', '--name', $Name, '--all'

    # We use ToString() here to turn the ErrorRecord into a string if we got an ErrorRecord
    if ($null -eq $res -or $res.ToString() -eq $lpassMessage.AccountNotFound) {
        # Will produce "Get-Secret : The secret $Name was not found." error.
        return
    }

    if ($res[0] -eq $lpassMessage.MultipleMatches) {
        Write-Warning "Multiple matches found with the name $Name. `nThe first matching result will be returned."
        $Id = [regex]::Match($res[1], '\[id: (.*)\]').Groups[1].value
        $res = Invoke-lpass 'show', '--name', $Id, '--all'

    }

    #The first line contains the secret name and ID. We do not have any use for it.
    $Raw = ($res | Select-Object -Skip 1) -join "`n"

    if ([String]::IsNullOrEmpty($Raw)) {
        return ""
    }

    # Custom type cannot have the same case-sensitive name but Username / uSERname work.
    # That's why we don't parse it directly to a hashtable.
    $MyMatches = @([regex]::Matches($raw, '(?<key>.*?)\: (?<value>.*?)(?:\n|$)')  | ForEach-Object {
            [PSCustomObject]@{
                key        = $_.Groups.Item('key').value
                value      = $_.Groups.Item('value').value 
                valueIndex = $_.Groups.Item('value').index
            }
        })

    # Notes is always the last item (lpass wise). This is also the only field that can be multiline.
    # Any matching items after the first "Notes" key need to be discarded as it is not an item,
    # but rather just part of the notes.
    $HasNote = $MyMatches.key -ccontains 'Notes' 
    if ($HasNote) {
        $start = $MyMatches.Where({$_.Key -ceq 'Notes'},'First')[0].valueIndex
        $Note = $raw.Substring($start)
        $MyMatches = $MyMatches.Where({$_.ValueIndex -lt $start})
    }
    $IsCustomType = $AdditionalParameters.outputType -eq 'Detailed' -or $MyMatches.key.Contains('NoteType')
    If ($IsCustomType) {
        $Output = Get-ComplexSecret -Fields $MyMatches -Note $Note 
    }
    else {
        $Output = Get-SimpleSecret -Fields $MyMatches -Note $Note 
    }
    
    return $Output
}

function Set-Secret
{
    [CmdletBinding()]
    param (
        [Parameter(ValueFromPipelineByPropertyName)]
        [string] $Name,
        [Parameter(ValueFromPipelineByPropertyName)]
        [object] $Secret,
        [Parameter(ValueFromPipelineByPropertyName)]
        [string] $VaultName,
        [Parameter(ValueFromPipelineByPropertyName)]
        [hashtable] $AdditionalParameters
    )
    if ($AdditionalParameters.Verbose) {
        $VerbosePreference = "Continue"
    }
    $sb = [System.Text.StringBuilder]::new()
    
    
    if ($Secret -is [string] -or $Secret -is [securestring]) {
        $Secret = @{
            URL = ' http://sn'
            Notes = $Secret
        }
    } elseif ($Secret -is [pscredential]) {
        $Secret = @{
            Username = $Secret.Username
            Password = $Secret.GetNetworkCredential().password
        }
    }

    if ($Secret -is [System.Collections.IDictionary]) {
        if ($Secret.Keys.count -eq 1 -and $null -ne $Secret.Notes) {
            $Secret.URL = 'http://sn'
        }

        $Keys = $Secret.Keys.Where({$_ -notin $SpecialKeys })
        foreach ($k in $Keys) {
            if ($Secret.$k -is [securestring]) {
                $Secret.$k = [System.Net.NetworkCredential]::new("", $Secret.$k).Password
            }
            $sb.AppendLine("$($k): $($Secret.$k)") | Out-Null
        }

        # Notes need to be on a new line
        if ($null -ne $Secret.Notes) {
            if ($Secret.Notes -is [securestring]) {
                $Secret.Notes = [System.Net.NetworkCredential]::new("", $Secret.Notes).Password
            }
            $sb.AppendLine("Notes: `n$($Secret.Notes)") | Out-Null
        }
    } 
    
    $res = Invoke-lpass 'show', '--sync=now', '--name', $Name

    # We use ToString() here to turn the ErrorRecord into a string if we got an ErrorRecord
    $SecretExists = switch -Wildcard ($res) {
        # This should never ever happen...
        "" {
            Write-Warning "Querying the secret $Name produced an unexpected result of `$Null"
            $false
            break
        }
        $lpassMessage.AccountNotFound {
            $false
            break
        }
        default {
            $true
            break
        }
    }

    if ($SecretExists) {
        Write-Verbose "Editing secret"
        $sb.ToString() | Invoke-lpass 'edit', '--non-interactive', $Name
    } else {
        Write-Verbose "Adding new secret"
        $NoteTypeArgs = @()
        if ($null -ne $Secret.NoteType) {
            if ($Secret.NoteType -is [securestring]) { 
                $Secret.NoteType = [System.Net.NetworkCredential]::new("", $Secret.NoteType).Password
            }
            $NoteTypeArgs += "--note-type=$($Secret.NoteType)"
        }
        $sb.ToString() | Invoke-lpass 'add', $Name, '--non-interactive', $NoteTypeArgs
    }

    # Explicit sync so calling set again does not duplicate the secret (add --sync=now not fast enough)
    Invoke-lpass 'sync'

    return $true
}

function Remove-Secret
{
    [CmdletBinding()]
    param (
        [Parameter(ValueFromPipelineByPropertyName)]
        [string] $Name,
        [Parameter(ValueFromPipelineByPropertyName)]
        [string] $VaultName,
        [Parameter(ValueFromPipelineByPropertyName)]
        [hashtable] $AdditionalParameters
    )

    # Grab the id because that's more exact
    if ($Name -match ".* \(id: (\d*)\)") {
        $Name = $Matches[1]
    }

    Invoke-lpass 'rm', $Name
    return $?
}

function Get-SecretInfo
{
    [CmdletBinding()]
    param (
        [string] $Filter,
        [string] $VaultName,
        [hashtable] $AdditionalParameters
    )
    if ($AdditionalParameters.Verbose) {
        $VerbosePreference = "Continue"
    }

    $Filter = "*$Filter"
    $pattern = [WildcardPattern]::new($Filter,[System.Management.Automation.WildcardOptions]::IgnoreCase)
    Invoke-lpass 'ls','-l' |
        Where-Object { 
            $IsMatch = $_ -match $lsLongOutput 
            if (-not $IsMatch ) { Write-Verbose -Message "No match for: $_ `nThis record will be ignored." }
            $IsMatch -and $pattern.IsMatch($Matches[3])
        } |
        ForEach-Object {
            $type = if ($AdditionalParameters.outputType -eq 'Detailed') {
                [SecretType]::Hashtable
            }
            elseif ($Matches[4]) {
                [SecretType]::PSCredential
            }
            else {
                [SecretType]::Unknown
            }

            [SecretInformation]::new(
                ($Matches[2] -replace '\[(id: \d*?)\]$', '($1)'), 
                $type,
                $VaultName)
        }
}

function Test-SecretVault
{
    [CmdletBinding()]
    param (
        [Parameter(ValueFromPipelineByPropertyName)]
        [string] $VaultName,
        [Parameter(ValueFromPipelineByPropertyName)]
        [hashtable] $AdditionalParameters
    )
    $status = Invoke-lpass 'status'
    return ($status -match "Logged in as .*")
}

function Get-SimpleSecret {
    [CmdletBinding()]
    param (
        $Fields,
        $Note
    )
    
    $username = $Fields.Where( { $_.key -eq 'Username' }, 'first') | Select-Object -ExpandProperty value
    $password = $Fields.Where( { $_.key -eq 'Password' }, 'first') | Select-Object -ExpandProperty value
    # Credentials
    if ($username -or $password) {
        if ($null -eq $username) { $username = '' }
        if ($null -eq $password) { $password = '' }
        if ("" -ne $password) { $password = $password | ConvertTo-SecureString -AsPlainText -Force }
        return [System.Management.Automation.PSCredential]::new($username, $password)
    }
    # Secure Note
    if ($null -ne $Note) {
        return $Note
    }
    # Empty secret
    return ''
}

function Get-ComplexSecret {
    [CmdletBinding()]
    param (
        $Fields,
        $Note
    )
    
    $Dupes = ($Fields | Group-Object key).Where( { $_.Count -gt 1 })
    # Notes is removed from the fields. If present, this mean we have another field using that name under a different case.
    $DupeNote = ($Fields.Contains('Notes') -and ![String]::IsNullOrEmpty($Note))
    if ($Dupes.Count -gt 0 -or $DupeNote) {
        Write-Verbose 'Creating case-sensitve hashtable'
        $Output = [System.Collections.Specialized.OrderedDictionary]::new([System.StringComparer]::CurrentCultureIgnoreCase)
    } else {
        $Output = [Ordered]@{}
    }
    
    Foreach ($f in $Fields) {
        try {
            $Output.Add($f.key, $f.value) 
        }
        catch {
            Write-Warning "$($f.key) field was not added."
        }
    }
    if ($null -ne $Output.NoteType -and $DefaultNoteTypeMap.ContainsKey($Output.NoteType)) {
        $Output.NoteType = $DefaultNoteTypeMap.Item($Output.NoteType)
    }

    if (![String]::IsNullOrEmpty($Note)) { 
        $Output.Notes = $Note
    }

    return $Output
}