kumquat-buildroot/fs/common.mk
Antoine Tenart b843d78173 fs/common.mk: set SELinux file security contexts
Set the SELinux file security contexts using setfiles when generating
root filesystem images.

Without such security contexts created at build time, they need to be
setup at first boot by running the restorecon utility on the target.
This has two drawbacks:

 - You have to special case the first boot, which cannot be done in
   enforcing mode, and will have to run restorecon, then reboot.

 - You cannot support read-only filesystems.

By setting up the security contexts at build time, we can have a
filesystem image that is immediately ready to boot an SELinux system
in enforcing mode, including if the root filesystem is read-only.

Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
2020-09-04 10:49:30 +02:00

223 lines
7.8 KiB
Makefile

#
# Macro that builds the needed Makefile target to create a root
# filesystem image.
#
# The following variable must be defined before calling this macro
#
# ROOTFS_$(FSTYPE)_CMD, the command that generates the root
# filesystem image. A single command is allowed. The filename of the
# filesystem image that it must generate is $$@.
#
# The following variables can optionaly be defined
#
# ROOTFS_$(FSTYPE)_DEPENDENCIES, the list of dependencies needed to
# build the root filesystem (usually host tools)
#
# ROOTFS_$(FSTYPE)_PRE_GEN_HOOKS, a list of hooks to call before
# generating the filesystem image
#
# ROOTFS_$(FSTYPE)_POST_GEN_HOOKS, a list of hooks to call after
# generating the filesystem image
#
# In terms of configuration option, this macro assumes that the
# BR2_TARGET_ROOTFS_$(FSTYPE) config option allows to enable/disable
# the generation of a filesystem image of a particular type. If
# the configuration options BR2_TARGET_ROOTFS_$(FSTYPE)_GZIP,
# BR2_TARGET_ROOTFS_$(FSTYPE)_BZIP2 or
# BR2_TARGET_ROOTFS_$(FSTYPE)_LZMA exist and are enabled, then the
# macro will automatically generate a compressed filesystem image.
FS_DIR = $(BUILD_DIR)/buildroot-fs
ROOTFS_DEVICE_TABLES = $(call qstrip,$(BR2_ROOTFS_DEVICE_TABLE) \
$(BR2_ROOTFS_STATIC_DEVICE_TABLE))
ROOTFS_USERS_TABLES = $(call qstrip,$(BR2_ROOTFS_USERS_TABLES))
ROOTFS_FULL_DEVICES_TABLE = $(FS_DIR)/full_devices_table.txt
ROOTFS_FULL_USERS_TABLE = $(FS_DIR)/full_users_table.txt
ifeq ($(BR2_REPRODUCIBLE),y)
define ROOTFS_REPRODUCIBLE
find $(TARGET_DIR) -print0 | xargs -0 -r touch -hd @$(SOURCE_DATE_EPOCH)
endef
endif
ROOTFS_COMMON_NAME = rootfs-common
ROOTFS_COMMON_TYPE = rootfs
ROOTFS_COMMON_DEPENDENCIES = \
host-fakeroot host-makedevs \
$(BR2_TAR_HOST_DEPENDENCY) \
$(if $(PACKAGES_USERS)$(ROOTFS_USERS_TABLES),host-mkpasswd)
ifeq ($(BR2_PACKAGE_REFPOLICY),y)
define ROOTFS_SELINUX
$(HOST_DIR)/sbin/setfiles -m -r $(TARGET_DIR) \
-c $(TARGET_DIR)/etc/selinux/targeted/policy/policy.$(BR2_PACKAGE_LIBSEPOL_POLICY_VERSION) \
$(TARGET_DIR)/etc/selinux/targeted/contexts/files/file_contexts \
$(TARGET_DIR)
endef
ROOTFS_COMMON_DEPENDENCIES += host-policycoreutils
endif
ROOTFS_COMMON_FINAL_RECURSIVE_DEPENDENCIES = $(sort \
$(if $(filter undefined,$(origin ROOTFS_COMMON_FINAL_RECURSIVE_DEPENDENCIES__X)), \
$(eval ROOTFS_COMMON_FINAL_RECURSIVE_DEPENDENCIES__X := \
$(foreach p, \
$(ROOTFS_COMMON_DEPENDENCIES), \
$(p) \
$($(call UPPERCASE,$(p))_FINAL_RECURSIVE_DEPENDENCIES) \
) \
) \
) \
$(ROOTFS_COMMON_FINAL_RECURSIVE_DEPENDENCIES__X))
.PHONY: rootfs-common
rootfs-common: $(ROOTFS_COMMON_DEPENDENCIES) target-finalize
@$(call MESSAGE,"Generating root filesystems common tables")
rm -rf $(FS_DIR)
mkdir -p $(FS_DIR)
$(call PRINTF,$(PACKAGES_USERS)) >> $(ROOTFS_FULL_USERS_TABLE)
ifneq ($(ROOTFS_USERS_TABLES),)
cat $(ROOTFS_USERS_TABLES) >> $(ROOTFS_FULL_USERS_TABLE)
endif
$(call PRINTF,$(PACKAGES_PERMISSIONS_TABLE)) > $(ROOTFS_FULL_DEVICES_TABLE)
ifneq ($(ROOTFS_DEVICE_TABLES),)
cat $(ROOTFS_DEVICE_TABLES) >> $(ROOTFS_FULL_DEVICES_TABLE)
endif
ifeq ($(BR2_ROOTFS_DEVICE_CREATION_STATIC),y)
$(call PRINTF,$(PACKAGES_DEVICES_TABLE)) >> $(ROOTFS_FULL_DEVICES_TABLE)
endif
rootfs-common-show-depends:
@echo $(ROOTFS_COMMON_DEPENDENCIES)
.PHONY: rootfs-common-show-info
rootfs-common-show-info:
@:
$(info $(call clean-json,{ $(call json-info,ROOTFS_COMMON) }))
# Since this function will be called from within an $(eval ...)
# all variable references except the arguments must be $$-quoted.
define inner-rootfs
ROOTFS_$(2)_NAME = rootfs-$(1)
ROOTFS_$(2)_TYPE = rootfs
ROOTFS_$(2)_IMAGE_NAME ?= rootfs.$(1)
ROOTFS_$(2)_FINAL_IMAGE_NAME = $$(strip $$(ROOTFS_$(2)_IMAGE_NAME))
ROOTFS_$(2)_DIR = $$(FS_DIR)/$(1)
ROOTFS_$(2)_TARGET_DIR = $$(ROOTFS_$(2)_DIR)/target
ROOTFS_$(2)_DEPENDENCIES += rootfs-common
ROOTFS_$(2)_FINAL_RECURSIVE_DEPENDENCIES = $$(sort \
$$(if $$(filter undefined,$$(origin ROOTFS_$(2)_FINAL_RECURSIVE_DEPENDENCIES__X)), \
$$(eval ROOTFS_$(2)_FINAL_RECURSIVE_DEPENDENCIES__X := \
$$(foreach p, \
$$(ROOTFS_$(2)_DEPENDENCIES), \
$$(p) \
$$($$(call UPPERCASE,$$(p))_FINAL_RECURSIVE_DEPENDENCIES) \
) \
) \
) \
$$(ROOTFS_$(2)_FINAL_RECURSIVE_DEPENDENCIES__X))
ifeq ($$(BR2_TARGET_ROOTFS_$(2)_GZIP),y)
ROOTFS_$(2)_COMPRESS_EXT = .gz
ROOTFS_$(2)_COMPRESS_CMD = gzip -9 -c -n
endif
ifeq ($$(BR2_TARGET_ROOTFS_$(2)_BZIP2),y)
ROOTFS_$(2)_COMPRESS_EXT = .bz2
ROOTFS_$(2)_COMPRESS_CMD = bzip2 -9 -c
endif
ifeq ($$(BR2_TARGET_ROOTFS_$(2)_LZMA),y)
ROOTFS_$(2)_DEPENDENCIES += host-lzma
ROOTFS_$(2)_COMPRESS_EXT = .lzma
ROOTFS_$(2)_COMPRESS_CMD = $$(LZMA) -9 -c
endif
ifeq ($$(BR2_TARGET_ROOTFS_$(2)_LZ4),y)
ROOTFS_$(2)_DEPENDENCIES += host-lz4
ROOTFS_$(2)_COMPRESS_EXT = .lz4
ROOTFS_$(2)_COMPRESS_CMD = lz4 -l -9 -c
endif
ifeq ($$(BR2_TARGET_ROOTFS_$(2)_LZO),y)
ROOTFS_$(2)_DEPENDENCIES += host-lzop
ROOTFS_$(2)_COMPRESS_EXT = .lzo
ROOTFS_$(2)_COMPRESS_CMD = $$(LZOP) -9 -c
endif
ifeq ($$(BR2_TARGET_ROOTFS_$(2)_XZ),y)
ROOTFS_$(2)_DEPENDENCIES += host-xz
ROOTFS_$(2)_COMPRESS_EXT = .xz
ROOTFS_$(2)_COMPRESS_CMD = xz -9 -C crc32 -c
ifeq ($(BR2_REPRODUCIBLE),)
ROOTFS_$(2)_COMPRESS_CMD += -T $(PARALLEL_JOBS)
endif
endif
$$(BINARIES_DIR)/$$(ROOTFS_$(2)_FINAL_IMAGE_NAME): ROOTFS=$(2)
$$(BINARIES_DIR)/$$(ROOTFS_$(2)_FINAL_IMAGE_NAME): FAKEROOT_SCRIPT=$$(ROOTFS_$(2)_DIR)/fakeroot
$$(BINARIES_DIR)/$$(ROOTFS_$(2)_FINAL_IMAGE_NAME): $$(ROOTFS_$(2)_DEPENDENCIES)
@$$(call MESSAGE,"Generating filesystem image $$(ROOTFS_$(2)_FINAL_IMAGE_NAME)")
mkdir -p $$(@D)
rm -rf $$(ROOTFS_$(2)_DIR)
mkdir -p $$(ROOTFS_$(2)_DIR)
rsync -auH \
--exclude=/$$(notdir $$(TARGET_DIR_WARNING_FILE)) \
$$(BASE_TARGET_DIR)/ \
$$(TARGET_DIR)
echo '#!/bin/sh' > $$(FAKEROOT_SCRIPT)
echo "set -e" >> $$(FAKEROOT_SCRIPT)
echo "chown -h -R 0:0 $$(TARGET_DIR)" >> $$(FAKEROOT_SCRIPT)
PATH=$$(BR_PATH) $$(TOPDIR)/support/scripts/mkusers $$(ROOTFS_FULL_USERS_TABLE) $$(TARGET_DIR) >> $$(FAKEROOT_SCRIPT)
echo "$$(HOST_DIR)/bin/makedevs -d $$(ROOTFS_FULL_DEVICES_TABLE) $$(TARGET_DIR)" >> $$(FAKEROOT_SCRIPT)
$$(foreach s,$$(call qstrip,$$(BR2_ROOTFS_POST_FAKEROOT_SCRIPT)),\
echo "echo '$$(TERM_BOLD)>>> Executing fakeroot script $$(s)$$(TERM_RESET)'" >> $$(FAKEROOT_SCRIPT); \
echo $$(EXTRA_ENV) $$(s) $$(TARGET_DIR) $$(BR2_ROOTFS_POST_SCRIPT_ARGS) >> $$(FAKEROOT_SCRIPT)$$(sep))
$$(foreach hook,$$(ROOTFS_PRE_CMD_HOOKS),\
$$(call PRINTF,$$($$(hook))) >> $$(FAKEROOT_SCRIPT)$$(sep))
$$(foreach hook,$$(ROOTFS_$(2)_PRE_GEN_HOOKS),\
$$(call PRINTF,$$($$(hook))) >> $$(FAKEROOT_SCRIPT)$$(sep))
$$(call PRINTF,$$(ROOTFS_REPRODUCIBLE)) >> $$(FAKEROOT_SCRIPT)
$$(call PRINTF,$$(ROOTFS_SELINUX)) >> $$(FAKEROOT_SCRIPT)
$$(call PRINTF,$$(ROOTFS_$(2)_CMD)) >> $$(FAKEROOT_SCRIPT)
chmod a+x $$(FAKEROOT_SCRIPT)
PATH=$$(BR_PATH) FAKEROOTDONTTRYCHOWN=1 $$(HOST_DIR)/bin/fakeroot -- $$(FAKEROOT_SCRIPT)
$(Q)rm -rf $$(TARGET_DIR)
ifneq ($$(ROOTFS_$(2)_COMPRESS_CMD),)
PATH=$$(BR_PATH) $$(ROOTFS_$(2)_COMPRESS_CMD) $$@ > $$@$$(ROOTFS_$(2)_COMPRESS_EXT)
endif
$$(foreach hook,$$(ROOTFS_$(2)_POST_GEN_HOOKS),$$(call $$(hook))$$(sep))
rootfs-$(1)-show-depends:
@echo $$(ROOTFS_$(2)_DEPENDENCIES)
rootfs-$(1)-show-info:
@:
$$(info $$(call clean-json,{ $$(call json-info,ROOTFS_$(2)) }))
rootfs-$(1): $$(BINARIES_DIR)/$$(ROOTFS_$(2)_FINAL_IMAGE_NAME)
.PHONY: rootfs-$(1) rootfs-$(1)-show-depends rootfs-$(1)-show-info
ifeq ($$(BR2_TARGET_ROOTFS_$(2)),y)
TARGETS_ROOTFS += rootfs-$(1)
PACKAGES += $$(filter-out rootfs-%,$$(ROOTFS_$(2)_FINAL_RECURSIVE_DEPENDENCIES))
endif
# Check for legacy POST_TARGETS rules
ifneq ($$(ROOTFS_$(2)_POST_TARGETS),)
$$(error Filesystem $(1) uses post-target rules, which are no longer supported.\
Update $(1) to use post-gen hooks instead)
endif
endef
# $(pkgname) also works well to return the filesystem name
rootfs = $(call inner-rootfs,$(pkgname),$(call UPPERCASE,$(pkgname)))
include $(sort $(wildcard fs/*/*.mk))