+ ifneq "$(filter stretch jessie buster, ${release})" ""
+ define SOURCES :=
+ deb http://cdn.debian.net/debian ${release} main
+ deb https://deb.debian.org/debian-security/ ${release}/updates main
+ endef
+ else
+ define SOURCES :=
+ deb http://cdn.debian.net/debian ${release} main
+ deb https://deb.debian.org/debian-security/ ${release}-security main
+ endef
+ endif