Protect-AESMessage.ps1
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Function Protect-AESMessage { <# .SYNOPSIS Encrypt AES256 message .PARAMETER Message Message to encrypt. .PARAMETER Password Password to encrypt message. .PARAMETER Salt Salt to encrypt message. Encrypt and decrypt must use the same salt .PARAMETER HashAlgorithm HashAlgorithm used for key to encrypt message. .EXAMPLE $Message = "A secret Message" $Result = Protect-AESMessage -Message $Message -Password "A Secret Password" -Salt @(1,2,3,4,5,6,7,9,10,11,252,253,254) $Result .NOTES Michal Gajda #> [CmdletBinding()] Param( [Parameter(Mandatory=$true)] [string]$Message, [Parameter(Mandatory=$true)] [string]$Password, [Parameter(Mandatory=$false)] [Byte[]]$Salt, [Parameter()] [ValidateSet("MD5","SHA1","SHA256","SHA384","SHA512")] [String]$HashAlgorithm = "SHA512" ) $MessageBytes = [System.Text.Encoding]::ASCII.GetBytes($Message) $PasswordBytes = [System.Text.Encoding]::ASCII.GetBytes($Password) # Salt must have at least 8 bytes! [Byte[]]$SaltBytes = @(21,251,43,109,115,57,88,24,249,222,68,134,79,196,197,169) if($Salt.Count -ge 8) { $SaltBytes = $Salt } [System.IO.MemoryStream] $MemoryStream = New-Object System.IO.MemoryStream [System.Security.Cryptography.Aes]$AES = [System.Security.Cryptography.Aes]::Create() $AES.KeySize = 256 $AES.BlockSize = 128 [System.Security.Cryptography.Rfc2898DeriveBytes] $Key = New-Object System.Security.Cryptography.Rfc2898DeriveBytes($PasswordBytes, $SaltBytes, 1000, [System.Security.Cryptography.HashAlgorithmName]::$HashAlgorithm) $AES.Key = $Key.GetBytes($AES.KeySize / 8) $AES.IV = $Key.GetBytes($AES.BlockSize / 8) $AES.Mode = [System.Security.Cryptography.CipherMode]::CBC $CryptoStream = New-Object System.Security.Cryptography.CryptoStream($MemoryStream, $AES.CreateEncryptor(), [System.Security.Cryptography.CryptoStreamMode]::Write) try { $CryptoStream.Write($MessageBytes, 0, $MessageBytes.Length) $CryptoStream.Close() } catch [Exception] { $Result = "Error occured while encoding string. Password, Salt or HashAlgorithm incorrect?" return $Result } $EncryptedBytes = $MemoryStream.ToArray() $Result = [System.Convert]::ToBase64String($EncryptedBytes) return $Result } |