DSCResources/POSHOrigin_vSphere_VM/Provisioners/Chef/helpers/_GetChecksum.ps1
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<#
.SYNOPSIS Return the checksum of the specified file #> param ( [Parameter(ParameterSetName="file")] [string] # Path to the file to get the checksum for $path, [Parameter(ParameterSetName="string")] [string] # The string to get the checksum for $string, [ValidateSet("sha1", "md5", "sha256")] [string] # Algorithm to use when generating the checksum $algorithm = "md5", [string] # The encoding method to use $encoding = "ASCII", [switch] # If trim is specified then the system will trim whitespace from the begining and end of input $trim, [switch] # Disable the Base64 encoding $nobase64 ) # $md5 = new-object -TypeName System.Security.Cryptography.MD5CryptoServiceProvider # $hash = [System.BitConverter]::ToString($md5.ComputeHash([System.IO.File]::ReadAllBytes($path))) $encoder = "{0}Encoding" -f $encoding $algo = "{0}CryptoServiceProvider" -f $algorithm $provider = New-Object -TypeName System.Security.Cryptography.$algo $engine = New-Object -TypeName System.Text.$encoder # Use the ParameterSetName to determine if a string or a path has been specified # If it is a path then get the contents switch ($PScmdlet.ParameterSetName) { "file" { $string = Get-Content -Path $path -Raw -Encoding UTF8 } } # Strip characters from the string # This is the the UNIX to Windows line ending problem # Ruby is UNIX based and will strip LF from files when they are read in #$string = $string -replace "`r", "" # work out the checksum of the file $hash = ([System.BitConverter]::ToString($provider.ComputeHash($engine.GetBytes($string)))).replace("-", "").tolower() if ($nobase64) { $checksum = $hash } else { # So that the hash is the same as that is generated by chef-client, it needs to be packed # and then base64 encoded $packed = for($i = 0; $i -lt $hash.length; $i += 2) { [char][int]::Parse($hash.substring($i,2), 'HexNumber') } # Now build up the checksum that is base64 encoded $checksum = & "$PSScriptRoot\_GetBase64.ps1" -data $packed } # Return the hash to the calling function return $checksum |