How to handle facebook's signed_request FORM Parameter in Coldfusion

cf_fb_signed_request.cfm

<!--- Check for the param --->
<cfparam name="FORM.signed_request" default="">

<!--- Split the param by the . --->
<cfset raw_str = ListGetAt(FORM.signed_request, 2, ".")>

<!--- Add padding if string is too short. ---> 
<!--- CF Fix: Exception invalid base64 string --->
<cfset res = Len(raw_str) % 4>
<cfif res eq 2>
     <cfset raw_str &= "==">
<cfelseif res eq 3>
     <cfset raw_str &= "=">
</cfif>

<!--- Base 64 Decode --->
<cfset result = ToString(BinaryDecode(raw_str, "Base64"))>

<!--- String to JSON --->
<cfset json = DeserializeJSON(result)>

Coldfusion and Facebook's signed_request Param

<!--- Check for the param --->
<cfparam name="FORM.signed_request" default="">

<!--- Split the param by the . --->
<cfset raw_str = ListGetAt(FORM.signed_request, 2, ".")>

<!--- Add padding if string is too short. ---> 
<!--- CF Fix: Exception invalid base64 string --->
<cfset res = Len(raw_str) % 4>
<cfif res eq 2>
     <cfset raw_str &= "==">
<cfelseif res eq 3>
     <cfset raw_str &= "=">
</cfif>

<!--- Base 64 Decode --->
<cfset result = ToString(BinaryDecode(raw_str, "Base64"))>

<!--- String to JSON --->
<cfset json = DeserializeJSON(result)>