Sets Content-Type header for given array of domains for F5 LTM via iRule

Site-X-CONTENT-TYPE.irule

#X-FRAME-OPTIONS iRule
#By: Pierce Fortin ([email protected])
#Checks for domain being requested on HTTP_Request, Sets flag for response rewrite if match 
#If match, It then checks for X-Frame-Options as existing, if it doesn't exist it adds X-FRAME-OPTION
#If match and header !exist, It adds it.
#v1.0 6/18/2018 Initial write


when RULE_INIT 
{
	set static::contenttypeDebugOn 0
}
when CLIENT_ACCEPTED 
{
	set logPrefix "[IP::client_addr]:[TCP::client_port]:contenttype:\[HTTPS\]:\t"
	if { $static::contenttypeDebugOn } { log local0. "$logPrefix: Client accepted" }
}

when HTTP_REQUEST {
	if { $static::contenttypeDebugOn } { log local0. "$logPrefix: ### Begin processing Incoming" }
	set iscontenttypeDomain 0
    array set contenttypeDomains 
    {
        "domain.com" 
        "domain2.com"
    }
    foreach domain [array get contenttypeDomains]
    {
		if { $static::contenttypeDebugOn } { log local0. "$logPrefix: Checking [HTTP::host] against $domain" }
        if { [string tolower [HTTP::host]] eq [string tolower $domain] } {
			if { $static::contenttypeDebugOn } { log local0. "$logPrefix: Current request is an contenttype domain. Processing" }
        	set iscontenttypeDomain 1
   		}
	}
}

when HTTP_RESPONSE {
	if { $static::contenttypeDebugOn } { log local0. "$logPrefix: Processing Response" }
    if { $iscontenttypeDomain eq 1 } {
    	if { $static::contenttypeDebugOn } { log local0. "$logPrefix: Current request is an contenttype domain. Inserting contenttype" }
        if { not([HTTP::header exists "X-Frame-Options"])}{
            if { $static::contenttypeDebugOn } { log local0. "$logPrefix: Could not find existing X-FRAME-OPTIONS header. Inserting" }
            HTTP::header insert "X-Content-Type-Options" "'nosniff'"
        }
        else {
            if { $static::contenttypeDebugOn } { log local0. "$logPrefix: Found existing X-FRAME-OPTIONS header, Replacing" }
            HTTP::header replace "X-Content-Type-Options" "'nosniff'"
        }     
	}
}