ssl

 cat Makefile 

#

# Makefile for the linux kernel signature checking certificates.

#

obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o

ifeq ($(CONFIG_SYSTEM_TRUSTED_KEYRING),y)

$(eval $(call config_filename,SYSTEM_TRUSTED_KEYS))

# GCC doesn't include .incbin files in -MD generated dependencies (PR#66871)

$(obj)/system_certificates.o: $(obj)/x509_certificate_list

# Cope with signing_key.x509 existing in $(srctree) not $(objtree)

AFLAGS_system_certificates.o := -I$(srctree)

quiet_cmd_extract_certs = EXTRACT_CERTS  $(patsubst "%",%,$(2))

   cmd_extract_certs = scripts/extract-cert $(2) $@ || ( rm $@; exit 1)

targets += x509_certificate_list

$(obj)/x509_certificate_list: scripts/extract-cert $(SYSTEM_TRUSTED_KEYS_SRCPREFIX)$(SYSTEM_TRUSTED_KEYS_FILENAME) FORCE

$(call if_changed,extract_certs,$(SYSTEM_TRUSTED_KEYS_SRCPREFIX)$(CONFIG_SYSTEM_TRUSTED_KEYS))

endif

clean-files := x509_certificate_list .x509.list

ifeq ($(CONFIG_MODULE_SIG),y)

###############################################################################

#

# If module signing is requested, say by allyesconfig, but a key has not been

# supplied, then one will need to be generated to make sure the build does not

# fail and that the kernel may be used afterwards.

#

###############################################################################

ifndef CONFIG_MODULE_SIG_HASH

$(error Could not determine digest type to use from kernel config)

endif

redirect_openssl = 2>&1

quiet_redirect_openssl = 2>&1

silent_redirect_openssl = 2>/dev/null

# We do it this way rather than having a boolean option for enabling an

# external private key, because 'make randconfig' might enable such a

# boolean option and we unfortunately can't make it depend on !RANDCONFIG.

ifeq ($(CONFIG_MODULE_SIG_KEY),"certs/signing_key.pem")

$(obj)/signing_key.pem: $(obj)/x509.genkey

@$(kecho) "###"

@$(kecho) "### Now generating an X.509 key pair to be used for signing modules."

@$(kecho) "###"

@$(kecho) "### If this takes a long time, you might wish to run rngd in the"

@$(kecho) "### background to keep the supply of entropy topped up. It"

@$(kecho) "### needs to be run as root, and uses a hardware random"

@$(kecho) "### number generator if one is available."

@$(kecho) "###"

$(Q)openssl req -new -nodes -utf8 -$(CONFIG_MODULE_SIG_HASH) -days 36500 \

-batch -x509 -config $(obj)/x509.genkey \

-outform PEM -out $(obj)/signing_key.pem \

-keyout $(obj)/signing_key.pem \

$($(quiet)redirect_openssl)

@$(kecho) "###"

@$(kecho) "### Key pair generated."

@$(kecho) "###"

$(obj)/x509.genkey:

@$(kecho) Generating X.509 key generation config

@echo >$@ "[ req ]"

@echo >>$@ "default_bits = 4096"

@echo >>$@ "distinguished_name = req_distinguished_name"

@echo >>$@ "prompt = no"

@echo >>$@ "string_mask = utf8only"

@echo >>$@ "x509_extensions = myexts"

@echo >>$@

@echo >>$@ "[ req_distinguished_name ]"

@echo >>$@ "#O = Unspecified company"

@echo >>$@ "CN = Build time autogenerated kernel key"

@echo >>$@ "#emailAddress = unspecified.user@unspecified.company"

@echo >>$@

@echo >>$@ "[ myexts ]"

@echo >>$@ "basicConstraints=critical,CA:FALSE"

@echo >>$@ "keyUsage=digitalSignature"

@echo >>$@ "subjectKeyIdentifier=hash"

@echo >>$@ "authorityKeyIdentifier=keyid"

endif

$(eval $(call config_filename,MODULE_SIG_KEY))

# If CONFIG_MODULE_SIG_KEY isn't a PKCS#11 URI, depend on it

ifeq ($(patsubst pkcs11:%,%,$(firstword $(MODULE_SIG_KEY_FILENAME))),$(firstword $(MODULE_SIG_KEY_FILENAME)))

X509_DEP := $(MODULE_SIG_KEY_SRCPREFIX)$(MODULE_SIG_KEY_FILENAME)

endif

# GCC PR#66871 again.

$(obj)/system_certificates.o: $(obj)/signing_key.x509

targets += signing_key.x509

$(obj)/signing_key.x509: scripts/extract-cert $(X509_DEP) FORCE

$(call if_changed,extract_certs,$(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY))

endif