build system: have tar use $SOURCE_DATE_EPOCH for --mtime

The --mtime argument to 'tar' sets the modification time for all files within
the archive, which determines the timestamp files will get when they are
extracted. In this case, rootfs and other tarballs will get mtimes which
correspond to the last commit timestamp of the build system, as reported by
git/subversion.

This is a step towards reproducible image builds.

Signed-off-by: bryan newbold <bnewbold@robocracy.org>
Signed-off-by: Alexander Couzens <lynxis@fe80.eu>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
SVN-Revision: 48586

diff --git a/include/image.mk b/include/image.mk
index 4eee4adfafe74c5499b68dce5fe2ce90f3a1ac42..8f81861fd08de08d14d350743ab90da47af747e5 100644 (file)
--- a/include/image.mk
+++ b/include/image.mk
@@ -186,7 +186,8 @@ ifneq ($(CONFIG_NAND_SUPPORT),)
        [ -z "$(2)" ] || $(CP) "$(KDIR)/root.$(2)" "$(KDIR_TMP)/sysupgrade-$(1)/root"
        [ -z "$(3)" ] || $(CP) "$(3)" "$(KDIR_TMP)/sysupgrade-$(1)/kernel"
        (cd "$(KDIR_TMP)"; $(TAR) cvf \
-               "$(BIN_DIR)/$(IMG_PREFIX)-$(1)-$(2)-sysupgrade.tar" sysupgrade-$(1))
+               "$(BIN_DIR)/$(IMG_PREFIX)-$(1)-$(2)-sysupgrade.tar" sysupgrade-$(1) \
+                       $(if $(SOURCE_DATE_EPOCH),--mtime="@$(SOURCE_DATE_EPOCH)")
    endef
 
 # $(1) board name
@@ -248,7 +249,10 @@ define Image/mkfs/cpiogz
 endef
 
 define Image/mkfs/targz
-       $(TAR) -czpf $(BIN_DIR)/$(IMG_PREFIX)$(if $(PROFILE_SANITIZED),-$(PROFILE_SANITIZED))-rootfs.tar.gz --numeric-owner --owner=0 --group=0 --sort=name -C $(TARGET_DIR)/ .
+       $(TAR) -czpf $(BIN_DIR)/$(IMG_PREFIX)$(if $(PROFILE_SANITIZED),-$(PROFILE_SANITIZED))-rootfs.tar.gz \
+               --numeric-owner --owner=0 --group=0 --sort=name \
+               $(if $(SOURCE_DATE_EPOCH),--mtime="@$(SOURCE_DATE_EPOCH)") \
+               -C $(TARGET_DIR)/ .
 endef
 
 E2SIZE=$(shell echo $$(($(CONFIG_TARGET_ROOTFS_PARTSIZE)*1024*1024)))

diff --git a/include/kernel-build.mk b/include/kernel-build.mk
index 8bfd9c89e31e72accd50e08866b92c846ff1c7b6..a52c90d9e7f84e6057d93fe89a99ff215f8e0a68 100644 (file)
--- a/include/kernel-build.mk
+++ b/include/kernel-build.mk
@@ -54,7 +54,9 @@ ifdef CONFIG_COLLECT_KERNEL_DEBUG
                $(STAGING_DIR_ROOT)/lib/modules/$(LINUX_VERSION)/* \
                $(KERNEL_BUILD_DIR)/debug/modules/
        $(FIND) $(KERNEL_BUILD_DIR)/debug -type f | $(XARGS) $(KERNEL_CROSS)strip --only-keep-debug
-       $(TAR) c -C $(KERNEL_BUILD_DIR) debug | bzip2 -c -9 > $(BIN_DIR)/kernel-debug.tar.bz2
+       $(TAR) c -C $(KERNEL_BUILD_DIR) debug \
+               $(if $(SOURCE_DATE_EPOCH),--mtime="@$(SOURCE_DATE_EPOCH)") \
+               | bzip2 -c -9 > $(BIN_DIR)/kernel-debug.tar.bz2
   endef
 endif
 

diff --git a/scripts/sysupgrade-nand.sh b/scripts/sysupgrade-nand.sh
index 92b326cbe98962293a84e842e8a4d278e46ff660..45b17daccd81587916ea640ab0406f766e2a43de 100755 (executable)
--- a/scripts/sysupgrade-nand.sh
+++ b/scripts/sysupgrade-nand.sh
@@ -56,7 +56,12 @@ echo "BOARD=${board}" > "${tmpdir}/sysupgrade-${board}/CONTROL"
 [ -z "${rootfs}" ] || cp "${rootfs}" "${tmpdir}/sysupgrade-${board}/root"
 [ -z "${kernel}" ] || cp "${kernel}" "${tmpdir}/sysupgrade-${board}/kernel"
 
-(cd "$tmpdir"; tar cvf sysupgrade.tar sysupgrade-${board})
+mtime=""
+if [ -n "$SOURCE_DATE_EPOCH" ]; then
+       mtime="--mtime=@${SOURCE_DATE_EPOCH}"
+fi
+
+(cd "$tmpdir"; tar cvf sysupgrade.tar sysupgrade-${board} ${mtime})
 err="$?"
 if [ -e "$tmpdir/sysupgrade.tar" ]; then
        cp "$tmpdir/sysupgrade.tar" "$outfile"