Public/Unprotect-AesString.ps1
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<# .SYNOPSIS Decrypts an AES Cipher to a String #> Function Unprotect-AesString { [CmdletBinding()] [OutputType([System.String])] Param ( [Parameter(Mandatory=$true)] [Object] $Key, [Parameter(Mandatory=$true)] [Alias("InitV")] [Object] $InitializationVector, [Parameter(Mandatory=$false)] [System.Security.Cryptography.CipherMode] $Mode = [System.Security.Cryptography.CipherMode]::CBC, [Parameter(Mandatory=$true)] [string] $Cipher ) # Create CSP $AesCsp = New-Object System.Security.Cryptography.AesCryptoServiceProvider # Setup Switch ($Key.GetType().Name) { 'String' { $AesCsp.Key = [System.Convert]::FromBase64String($Key); Break } 'Byte[]' { $AesCsp.Key = $Key; Break } Default { Throw "Key must be a String or ByteArray" } } Switch ($InitializationVector.GetType().Name) { 'String' { $AesCsp.IV = [System.Convert]::FromBase64String($InitializationVector); Break } 'Byte[]' { $AesCsp.IV = $InitializationVector; Break } Default { Throw "Initialization Vector must be a String or ByteArray" } } $AesCsp.Mode = $Mode # Decrypt $EncryptedBytes = [System.Convert]::FromBase64String($Cipher) $UnencryptedBytes = $AesCsp.CreateDecryptor().TransformFinalBlock($EncryptedBytes, 0, $EncryptedBytes.Length) $R = [System.Text.Encoding]::UTF8.GetString($UnencryptedBytes) # Cleanup $AesCsp.Dispose() Return $R } Export-ModuleMember -Function Unprotect-AesString |