Makefile_USBKEY

targets := \
	header.img \
	usb-key-plain.img \
	usb-key-crypt.img

wait_for_file = \
	until test -e '$(1)'; do \
		echo 'waiting for file "$(1)"...' && sleep 1; \
	done


.PHONY: all
all: $(targets)

dummy.img:
	dd if=/dev/zero of=$(@) bs=1M count=1

header.key:
	head -c 4096 /dev/urandom > $(@)

header.img: header.key | dummy.img
	dd if=/dev/zero of=$(@) bs=16M count=1
	sudo cryptsetup \
		--header $(@) \
		--key-file $(^) \
		luksFormat $(|)
	@echo '================================='
	@echo '== This is the password for the "crypt" usb-key'
	sudo cryptsetup \
		--key-file $(^) \
		--iter-time=10000 \
		luksAddKey $(@)
	cryptsetup luksDump $(@)


.PRECIOUS: loop-%.img

usb-key-%.img:
	make fs-$(*) fs-format-$(*) fs-deinit-$(*)
	mv loop-$(*).img $(@)
	sha256sum $(@)

fs-%: \
		/dev/disk/by-label/usb-key-% | loop-%.dev
	mkdir -p fs-$(*)
	sudo mount '$(^)' fs-$(*)

.PHONY: fs-format-crypt
fs-format-crypt: | fs-crypt/header.img
	sha256sum header.img $(|)

.PHONY: fs-format-plain
fs-format-plain: | fs-plain/header.img fs-plain/header.key
	sha256sum header.img header.key $(|)

fs-deinit-%: \
		| /dev/disk/by-label/usb-key-% loop-%.dev
	find fs-$(*) | sort
	sudo umount fs-$(*)
	rmdir fs-$(*)
	sudo losetup -d '$(realpath loop-$(*).dev)'

fs-%/header.img: header.img | fs-%
	sudo cp $(^) $(@)

fs-%/header.key: header.key | fs-%
	sudo cp $(^) $(@)

/dev/disk/by-label/usb-key-%: \
		/dev/disk/by-partlabel/usb-key-% | loop-%.dev
	sudo mkfs.ext4 '$(^)' -L usb-key-$(*)
	$(call wait_for_file,$(@))

/dev/disk/by-partlabel/usb-key-%: \
		conf/sfdisk-%.conf | loop-%.dev
	cat '$(^)' | sudo sfdisk '$(realpath $(|))'
	$(call wait_for_file,$(@))

loop-%.dev: loop-%.img
	ln -s $$(sudo losetup --show -fP $(^)) $(@)

loop-%.img:
	dd if=/dev/urandom of=$(@) bs=1M count=64 status=progress


.PHONY: clean
clean:
	rm -f dummy.img

.PHONY: clean-all
clean-all: clean
	rm -f $(targets) header.key
	sudo umount fs-plain || true
	sudo umount fs-crypt || true
	rmdir fs-plain fs-crypt || true
	rm -f loop-plain.img loop-crypt.img
	sudo losetup -d \
		$$(losetup -ln -O NAME,BACK-FILE \
			| grep '$(shell pwd)/loop' \
			| awk '{print $$1}') >/dev/null 2>&1 \
				|| true

.PHONY: list
list:
	@lsblk -do name,tran,size,type,mountpoint | grep ' usb ' || \
		for x in /sys/block/*; do \
			v=$$(udevadm info -q property $$x); \
			echo '$$v' | grep -q '^ID_BUS=usb' || continue; \
			echo '$$v' | grep '^DEVLINKS=' | sed 's|DEVLINKS=||g' \
				| xargs printf '%s\n' | grep '^/dev/disk/by-id/'; \
		done