--- a/make-rules/prep-download.mk	Thu May 21 09:51:37 2015 -0700
+++ b/make-rules/prep-download.mk	Thu May 21 16:49:12 2015 -0700
@@ -65,3 +65,6 @@
 #
 $(eval $(call download-rules,))
 $(foreach suffix, $(URL_SUFFIXES), $(eval $(call download-rules,_$(suffix))))
+
+# Needed for signature validation of downloads
+REQUIRED_PACKAGES += crypto/gnupg