#Modified by Keegan Jacobson
#Source https://devcentral.f5.com/codeshare?sid=500

when RULE_INIT {
 
	# Cookie name prefix
	set static::ck_pattern "BIGipServer*"
 
	# Log debug to /var/log/ltm? 1=yes, 0=no)
	set static::ck_debug 0
 
	# Cookie encryption passphrase
	# Change this to a custom string!
	set static::ck_pass "SET_COOKIE_HERE_LEAVE_THE_QUOTES_THOUGH"
}
when HTTP_REQUEST {
 
	if {$static::ck_debug}{log local0. "Request cookie names: [HTTP::cookie names]"}
	
	# Check if the cookie names in the request match our string glob pattern
	if {[set cookie_names [lsearch -all -inline [HTTP::cookie names] $static::ck_pattern]] ne ""}{
 
		# We have at least one match so loop through the cookie(s) by name
		if {$static::ck_debug}{log local0. "Matching cookie names: [HTTP::cookie names]"}
		foreach cookie_name $cookie_names {
			
			# Decrypt the cookie value and check if the decryption failed (null return value)
			if {[HTTP::cookie decrypt $cookie_name $static::ck_pass] eq ""}{
 
				# Cookie wasn't encrypted, delete it
				if {$static::ck_debug}{log local0. "Removing cookie as decryption failed for $cookie_name"}
				HTTP::cookie remove $cookie_name
			}
		}
		if {$static::ck_debug}{log local0. "Cookie header(s): [HTTP::header values Cookie]"}
	}
}
when HTTP_RESPONSE {
 
	if {$static::ck_debug}{log local0. "Response cookie names: [HTTP::cookie names]"}
	
	# Check if the cookie names in the request match our string glob pattern
	if {[set cookie_names [lsearch -all -inline [HTTP::cookie names] $static::ck_pattern]] ne ""}{
		
		# We have at least one match so loop through the cookie(s) by name
		if {$static::ck_debug}{log local0. "Matching cookie names: [HTTP::cookie names]"}
		foreach cookie_name $cookie_names {
			
			# Encrypt the cookie value
			HTTP::cookie encrypt $cookie_name $static::ck_pass
		}
		if {$static::ck_debug}{log local0. "Set-Cookie header(s): [HTTP::header values Set-Cookie]"}
	}
}