diff --git a/webif/lib/ts.class b/webif/lib/ts.class
index 34087cf..68817ca 100644
--- a/webif/lib/ts.class
+++ b/webif/lib/ts.class
@@ -2,6 +2,7 @@
 if {![exists -proc class]} { package require oo }
 if {![exists -proc pack]} { package require pack }
 if {![exists -proc xconv]} { package require xconv }
+if {![exists -proc binary]} { package require binary }
 source /mod/webif/lib/setup
 require system.class tvdb.class classdump
 
@@ -829,3 +830,41 @@ proc {ts genrelist} {} {
 	return $glist
 }
 
+# return the key that will decrypt the file in the mode, or nothing
+ts method getkey {mode} {
+	# mode: dlna (active key), direct
+
+	set rfile [file rootname $file]
+
+	# the active key
+	set keys = {}
+	set key [string range [system nugget cryptokey -key] 0 31]
+	if {$key ne ""} {
+		lappend keys $key
+	}
+	if { mode ne "dlna" } {
+		# also try other keys, such as the native key 
+		if {![catch {set fd [open "/mod/boot/cryptokey"]}]} {
+			set bytes [$fd read 16]
+				$fd close
+				binary scan $bytes H* key
+				if {[string length $key] == 32} {
+					if {$key ni $keys} {
+						lappend keys $key
+					}
+			}
+		}
+		set key [system encryptionkey]
+		if {$key ni $keys} {
+			lappend keys $key
+		}
+	}
+
+	foreach key $keys {
+		if {[catch {
+			set ret [exec /mod/bin/stripts -q/ $key $rfile]
+		}]} continue
+		if {$ret eq "1"} return $key
+	}
+	return
+}