SwissKnife

1.0.0-preview6

functions/security/ConvertFrom-EncryptedString.ps1

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 function ConvertFrom-EncryptedString {
    param(
        [Parameter(Mandatory = $true, ValueFromPipeline = $true)]
        [string]$EncryptedString,
        [Parameter(Mandatory = $false)]
        [switch]$AsPlainText,
        [Parameter(Mandatory = $false)]
        [ValidateSet('CurrentUser', 'LocalMachine')]
        [System.Security.Cryptography.DataProtectionScope]$Scope = [System.Security.Cryptography.DataProtectionScope]::CurrentUser
    )
    
    begin {
        $entropy = Get-Entropy
    }
    process {
        $decryptedData = [System.Security.Cryptography.ProtectedData]::Unprotect(
            [System.Convert]::FromBase64String($EncryptedString), 
            [System.Text.Encoding]::Unicode.GetBytes($entropy), 
            $Scope)
        
        $decrtypted = [System.Text.Encoding]::Unicode.GetString($decryptedData)

        if ($AsPlainText) {
            $decrtypted
        }
        else {
            ConvertTo-SecureString -String $decrtypted -AsPlainText
        }
    }
}