Pub/Priv/Cert Makefile with help task

Makefile

KEY_NAME?=key
KEY_LENGTH?=1024
CERT_EXPIRY?=3652 # 10 years

all: help

.PHONY: clean
clean: ## Clean up all generated keys
	rm -f *.crt *.pkcs12 *.private *.public

.PHONY: help
help: ##  Display this help text
	@echo "Available commands:\n"
	@grep -h "##" $(MAKEFILE_LIST) | grep -v grep | sed -e 's/\\$$//;s/##//;s/://'
	@echo "\n\
	KEY_NAME=$(KEY_NAME)\n\
	KEY_LENGTH=$(KEY_LENGTH)\n\
	CERT_EXPIRY=$(CERT_EXPIRY)"

.PHONY: key
key: ##   Generate a valid PKCS8 RSA key pair
key: $(KEY_NAME).pkcs12 $(KEY_NAME).private $(KEY_NAME).public $(KEY_NAME).crt

.PHONY: $(KEY_NAME)-clean
$(KEY_NAME)-clean:
	rm -f $(KEY_NAME).crt $(KEY_NAME).pkcs12 $(KEY_NAME).private $(KEY_NAME).public

$(KEY_NAME).crt:
	openssl req -x509 -new -key $(KEY_NAME).private -out $(KEY_NAME).crt -days $(CERT_EXPIRY)

$(KEY_NAME).pkcs12:
	openssl genrsa -out $(KEY_NAME).pkcs12 $(KEY_LENGTH)

$(KEY_NAME).private:
	openssl pkcs8 -topk8 -nocrypt -inform pem -outform pem -in $(KEY_NAME).pkcs12 -out $(KEY_NAME).private

$(KEY_NAME).public:
	openssl rsa -in $(KEY_NAME).pkcs12 -pubout > $(KEY_NAME).public