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authorDavid Howells <dhowells@redhat.com>2015-08-14 15:20:41 +0100
committerDavid Woodhouse <David.Woodhouse@intel.com>2015-08-14 16:06:13 +0100
commitcfc411e7fff3e15cd6354ff69773907e2c9d1c0c (patch)
treec67e679c1c2bbe4a657ce58d60e995c63535952b
parent0e38c35815f50e5a347977d76fb5eb4c3bf020b5 (diff)
download96b-common-cfc411e7fff3e15cd6354ff69773907e2c9d1c0c.tar.gz
Move certificate handling to its own directory
Move certificate handling out of the kernel/ directory and into a certs/ directory to get all the weird stuff in one place and move the generated signing keys into this directory. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: David Woodhouse <David.Woodhouse@intel.com>
-rw-r--r--Documentation/module-signing.txt18
-rw-r--r--MAINTAINERS9
-rw-r--r--Makefile4
-rw-r--r--certs/Kconfig42
-rw-r--r--certs/Makefile147
-rw-r--r--certs/system_certificates.S (renamed from kernel/system_certificates.S)4
-rw-r--r--certs/system_keyring.c (renamed from kernel/system_keyring.c)0
-rw-r--r--crypto/Kconfig1
-rw-r--r--init/Kconfig39
-rw-r--r--kernel/Makefile143
10 files changed, 212 insertions, 195 deletions
diff --git a/Documentation/module-signing.txt b/Documentation/module-signing.txt
index 02a9baf1c72f..a78bf1ffa68c 100644
--- a/Documentation/module-signing.txt
+++ b/Documentation/module-signing.txt
@@ -92,13 +92,13 @@ This has a number of options available:
(4) "File name or PKCS#11 URI of module signing key" (CONFIG_MODULE_SIG_KEY)
Setting this option to something other than its default of
- "signing_key.pem" will disable the autogeneration of signing keys and
- allow the kernel modules to be signed with a key of your choosing.
- The string provided should identify a file containing both a private
- key and its corresponding X.509 certificate in PEM form, or — on
- systems where the OpenSSL ENGINE_pkcs11 is functional — a PKCS#11 URI
- as defined by RFC7512. In the latter case, the PKCS#11 URI should
- reference both a certificate and a private key.
+ "certs/signing_key.pem" will disable the autogeneration of signing keys
+ and allow the kernel modules to be signed with a key of your choosing.
+ The string provided should identify a file containing both a private key
+ and its corresponding X.509 certificate in PEM form, or — on systems where
+ the OpenSSL ENGINE_pkcs11 is functional — a PKCS#11 URI as defined by
+ RFC7512. In the latter case, the PKCS#11 URI should reference both a
+ certificate and a private key.
If the PEM file containing the private key is encrypted, or if the
PKCS#11 token requries a PIN, this can be provided at build time by
@@ -130,12 +130,12 @@ Under normal conditions, when CONFIG_MODULE_SIG_KEY is unchanged from its
default, the kernel build will automatically generate a new keypair using
openssl if one does not exist in the file:
- signing_key.pem
+ certs/signing_key.pem
during the building of vmlinux (the public part of the key needs to be built
into vmlinux) using parameters in the:
- x509.genkey
+ certs/x509.genkey
file (which is also generated if it does not already exist).
diff --git a/MAINTAINERS b/MAINTAINERS
index bde2e3f5a10b..294dc59ed5e1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2589,6 +2589,15 @@ S: Supported
F: Documentation/filesystems/ceph.txt
F: fs/ceph/
+CERTIFICATE HANDLING:
+M: David Howells <dhowells@redhat.com>
+M: David Woodhouse <dwmw2@infradead.org>
+L: keyrings@linux-nfs.org
+S: Maintained
+F: Documentation/module-signing.txt
+F: certs/
+F: scripts/extract-cert.c
+
CERTIFIED WIRELESS USB (WUSB) SUBSYSTEM:
L: linux-usb@vger.kernel.org
S: Orphan
diff --git a/Makefile b/Makefile
index 6ab99d8cc23c..2341942feb85 100644
--- a/Makefile
+++ b/Makefile
@@ -871,7 +871,7 @@ INITRD_COMPRESS-$(CONFIG_RD_LZ4) := lz4
ifdef CONFIG_MODULE_SIG_ALL
MODSECKEY = $(CONFIG_MODULE_SIG_KEY)
-MODPUBKEY = ./signing_key.x509
+MODPUBKEY = certs/signing_key.x509
export MODPUBKEY
mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODSECKEY) $(MODPUBKEY)
else
@@ -881,7 +881,7 @@ export mod_sign_cmd
ifeq ($(KBUILD_EXTMOD),)
-core-y += kernel/ mm/ fs/ ipc/ security/ crypto/ block/
+core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
vmlinux-dirs := $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
$(core-y) $(core-m) $(drivers-y) $(drivers-m) \
diff --git a/certs/Kconfig b/certs/Kconfig
new file mode 100644
index 000000000000..b030b9c7ed34
--- /dev/null
+++ b/certs/Kconfig
@@ -0,0 +1,42 @@
+menu "Certificates for signature checking"
+
+config MODULE_SIG_KEY
+ string "File name or PKCS#11 URI of module signing key"
+ default "certs/signing_key.pem"
+ depends on MODULE_SIG
+ help
+ Provide the file name of a private key/certificate in PEM format,
+ or a PKCS#11 URI according to RFC7512. The file should contain, or
+ the URI should identify, both the certificate and its corresponding
+ private key.
+
+ If this option is unchanged from its default "certs/signing_key.pem",
+ then the kernel will automatically generate the private key and
+ certificate as described in Documentation/module-signing.txt
+
+config SYSTEM_TRUSTED_KEYRING
+ bool "Provide system-wide ring of trusted keys"
+ depends on KEYS
+ help
+ Provide a system keyring to which trusted keys can be added. Keys in
+ the keyring are considered to be trusted. Keys may be added at will
+ by the kernel from compiled-in data and from hardware key stores, but
+ userspace may only add extra keys if those keys can be verified by
+ keys already in the keyring.
+
+ Keys in this keyring are used by module signature checking.
+
+config SYSTEM_TRUSTED_KEYS
+ string "Additional X.509 keys for default system keyring"
+ depends on SYSTEM_TRUSTED_KEYRING
+ help
+ If set, this option should be the filename of a PEM-formatted file
+ containing trusted X.509 certificates to be included in the default
+ system keyring. Any certificate used for module signing is implicitly
+ also trusted.
+
+ NOTE: If you previously provided keys for the system keyring in the
+ form of DER-encoded *.x509 files in the top-level build directory,
+ those are no longer used. You will need to set this option instead.
+
+endmenu
diff --git a/certs/Makefile b/certs/Makefile
new file mode 100644
index 000000000000..5d33486d3b20
--- /dev/null
+++ b/certs/Makefile
@@ -0,0 +1,147 @@
+#
+# Makefile for the linux kernel signature checking certificates.
+#
+
+obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o
+
+###############################################################################
+#
+# When a Kconfig string contains a filename, it is suitable for
+# passing to shell commands. It is surrounded by double-quotes, and
+# any double-quotes or backslashes within it are escaped by
+# backslashes.
+#
+# This is no use for dependencies or $(wildcard). We need to strip the
+# surrounding quotes and the escaping from quotes and backslashes, and
+# we *do* need to escape any spaces in the string. So, for example:
+#
+# Usage: $(eval $(call config_filename,FOO))
+#
+# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option,
+# transformed as described above to be suitable for use within the
+# makefile.
+#
+# Also, if the filename is a relative filename and exists in the source
+# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to
+# be prefixed to *both* command invocation and dependencies.
+#
+# Note: We also print the filenames in the quiet_cmd_foo text, and
+# perhaps ought to have a version specially escaped for that purpose.
+# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good
+# enough. It'll strip the quotes in the common case where there's no
+# space and it's a simple filename, and it'll retain the quotes when
+# there's a space. There are some esoteric cases in which it'll print
+# the wrong thing, but we don't really care. The actual dependencies
+# and commands *do* get it right, with various combinations of single
+# and double quotes, backslashes and spaces in the filenames.
+#
+###############################################################################
+#
+quote := $(firstword " ")
+space :=
+space +=
+space_escape := %%%SPACE%%%
+#
+define config_filename
+ifneq ($$(CONFIG_$(1)),"")
+$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
+ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
+else
+ifeq ($$(wildcard $$($(1)_FILENAME)),)
+ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
+$(1)_SRCPREFIX := $(srctree)/
+endif
+endif
+endif
+endif
+endef
+#
+###############################################################################
+
+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
+
+# 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
+ @echo "###"
+ @echo "### Now generating an X.509 key pair to be used for signing modules."
+ @echo "###"
+ @echo "### If this takes a long time, you might wish to run rngd in the"
+ @echo "### background to keep the supply of entropy topped up. It"
+ @echo "### needs to be run as root, and uses a hardware random"
+ @echo "### number generator if one is available."
+ @echo "###"
+ 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 2>&1
+ @echo "###"
+ @echo "### Key pair generated."
+ @echo "###"
+
+$(obj)/x509.genkey:
+ @echo 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
+
+$(obj)/signing_key.x509: scripts/extract-cert include/config/module/sig/key.h $(X509_DEP)
+ $(call cmd,extract_certs,$(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY))
+endif
diff --git a/kernel/system_certificates.S b/certs/system_certificates.S
index 6ba2f75e7ba5..9216e8c81764 100644
--- a/kernel/system_certificates.S
+++ b/certs/system_certificates.S
@@ -8,9 +8,9 @@
VMLINUX_SYMBOL(system_certificate_list):
__cert_list_start:
#ifdef CONFIG_MODULE_SIG
- .incbin "signing_key.x509"
+ .incbin "certs/signing_key.x509"
#endif
- .incbin "kernel/x509_certificate_list"
+ .incbin "certs/x509_certificate_list"
__cert_list_end:
.align 8
diff --git a/kernel/system_keyring.c b/certs/system_keyring.c
index 2570598b784d..2570598b784d 100644
--- a/kernel/system_keyring.c
+++ b/certs/system_keyring.c
diff --git a/crypto/Kconfig b/crypto/Kconfig
index b4cfc5754033..51b01de7c0ae 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1601,5 +1601,6 @@ config CRYPTO_HASH_INFO
source "drivers/crypto/Kconfig"
source crypto/asymmetric_keys/Kconfig
+source certs/Kconfig
endif # if CRYPTO
diff --git a/init/Kconfig b/init/Kconfig
index 5d1a703663ad..5526dfaac628 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1740,31 +1740,6 @@ config MMAP_ALLOW_UNINITIALIZED
See Documentation/nommu-mmap.txt for more information.
-config SYSTEM_TRUSTED_KEYRING
- bool "Provide system-wide ring of trusted keys"
- depends on KEYS
- help
- Provide a system keyring to which trusted keys can be added. Keys in
- the keyring are considered to be trusted. Keys may be added at will
- by the kernel from compiled-in data and from hardware key stores, but
- userspace may only add extra keys if those keys can be verified by
- keys already in the keyring.
-
- Keys in this keyring are used by module signature checking.
-
-config SYSTEM_TRUSTED_KEYS
- string "Additional X.509 keys for default system keyring"
- depends on SYSTEM_TRUSTED_KEYRING
- help
- If set, this option should be the filename of a PEM-formatted file
- containing trusted X.509 certificates to be included in the default
- system keyring. Any certificate used for module signing is implicitly
- also trusted.
-
- NOTE: If you previously provided keys for the system keyring in the
- form of DER-encoded *.x509 files in the top-level build directory,
- those are no longer used. You will need to set this option instead.
-
config SYSTEM_DATA_VERIFICATION
def_bool n
select SYSTEM_TRUSTED_KEYRING
@@ -1965,20 +1940,6 @@ config MODULE_SIG_HASH
default "sha384" if MODULE_SIG_SHA384
default "sha512" if MODULE_SIG_SHA512
-config MODULE_SIG_KEY
- string "File name or PKCS#11 URI of module signing key"
- default "signing_key.pem"
- depends on MODULE_SIG
- help
- Provide the file name of a private key/certificate in PEM format,
- or a PKCS#11 URI according to RFC7512. The file should contain, or
- the URI should identify, both the certificate and its corresponding
- private key.
-
- If this option is unchanged from its default "signing_key.pem",
- then the kernel will automatically generate the private key and
- certificate as described in Documentation/module-signing.txt
-
config MODULE_COMPRESS
bool "Compress modules on installation"
depends on MODULES
diff --git a/kernel/Makefile b/kernel/Makefile
index 65ef3846fbe8..1aa153a1be21 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -45,7 +45,6 @@ ifneq ($(CONFIG_SMP),y)
obj-y += up.o
endif
obj-$(CONFIG_UID16) += uid16.o
-obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o
obj-$(CONFIG_MODULES) += module.o
obj-$(CONFIG_MODULE_SIG) += module_signing.o
obj-$(CONFIG_KALLSYMS) += kallsyms.o
@@ -111,145 +110,3 @@ $(obj)/config_data.gz: $(KCONFIG_CONFIG) FORCE
targets += config_data.h
$(obj)/config_data.h: $(obj)/config_data.gz FORCE
$(call filechk,ikconfiggz)
-
-###############################################################################
-#
-# When a Kconfig string contains a filename, it is suitable for
-# passing to shell commands. It is surrounded by double-quotes, and
-# any double-quotes or backslashes within it are escaped by
-# backslashes.
-#
-# This is no use for dependencies or $(wildcard). We need to strip the
-# surrounding quotes and the escaping from quotes and backslashes, and
-# we *do* need to escape any spaces in the string. So, for example:
-#
-# Usage: $(eval $(call config_filename,FOO))
-#
-# Defines FOO_FILENAME based on the contents of the CONFIG_FOO option,
-# transformed as described above to be suitable for use within the
-# makefile.
-#
-# Also, if the filename is a relative filename and exists in the source
-# tree but not the build tree, define FOO_SRCPREFIX as $(srctree)/ to
-# be prefixed to *both* command invocation and dependencies.
-#
-# Note: We also print the filenames in the quiet_cmd_foo text, and
-# perhaps ought to have a version specially escaped for that purpose.
-# But it's only cosmetic, and $(patsubst "%",%,$(CONFIG_FOO)) is good
-# enough. It'll strip the quotes in the common case where there's no
-# space and it's a simple filename, and it'll retain the quotes when
-# there's a space. There are some esoteric cases in which it'll print
-# the wrong thing, but we don't really care. The actual dependencies
-# and commands *do* get it right, with various combinations of single
-# and double quotes, backslashes and spaces in the filenames.
-#
-###############################################################################
-#
-quote := $(firstword " ")
-space :=
-space +=
-space_escape := %%%SPACE%%%
-#
-define config_filename
-ifneq ($$(CONFIG_$(1)),"")
-$(1)_FILENAME := $$(subst \\,\,$$(subst \$$(quote),$$(quote),$$(subst $$(space_escape),\$$(space),$$(patsubst "%",%,$$(subst $$(space),$$(space_escape),$$(CONFIG_$(1)))))))
-ifneq ($$(patsubst /%,%,$$(firstword $$($(1)_FILENAME))),$$(firstword $$($(1)_FILENAME)))
-else
-ifeq ($$(wildcard $$($(1)_FILENAME)),)
-ifneq ($$(wildcard $$(srctree)/$$($(1)_FILENAME)),)
-$(1)_SRCPREFIX := $(srctree)/
-endif
-endif
-endif
-endif
-endef
-#
-###############################################################################
-
-ifeq ($(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
-$(error Could not determine digest type to use from kernel config)
-endif
-
-# We do it this way rather than having a boolean option for enabling an
-# external private key, because 'make randconfig' might enable such a
-# boolean option and we unfortunately can't make it depend on !RANDCONFIG.
-ifeq ($(CONFIG_MODULE_SIG_KEY),"signing_key.pem")
-signing_key.pem: x509.genkey
- @echo "###"
- @echo "### Now generating an X.509 key pair to be used for signing modules."
- @echo "###"
- @echo "### If this takes a long time, you might wish to run rngd in the"
- @echo "### background to keep the supply of entropy topped up. It"
- @echo "### needs to be run as root, and uses a hardware random"
- @echo "### number generator if one is available."
- @echo "###"
- openssl req -new -nodes -utf8 -$(CONFIG_MODULE_SIG_HASH) -days 36500 \
- -batch -x509 -config x509.genkey \
- -outform PEM -out signing_key.pem \
- -keyout signing_key.pem 2>&1
- @echo "###"
- @echo "### Key pair generated."
- @echo "###"
-
-x509.genkey:
- @echo Generating X.509 key generation config
- @echo >x509.genkey "[ req ]"
- @echo >>x509.genkey "default_bits = 4096"
- @echo >>x509.genkey "distinguished_name = req_distinguished_name"
- @echo >>x509.genkey "prompt = no"
- @echo >>x509.genkey "string_mask = utf8only"
- @echo >>x509.genkey "x509_extensions = myexts"
- @echo >>x509.genkey
- @echo >>x509.genkey "[ req_distinguished_name ]"
- @echo >>x509.genkey "#O = Unspecified company"
- @echo >>x509.genkey "CN = Build time autogenerated kernel key"
- @echo >>x509.genkey "#emailAddress = unspecified.user@unspecified.company"
- @echo >>x509.genkey
- @echo >>x509.genkey "[ myexts ]"
- @echo >>x509.genkey "basicConstraints=critical,CA:FALSE"
- @echo >>x509.genkey "keyUsage=digitalSignature"
- @echo >>x509.genkey "subjectKeyIdentifier=hash"
- @echo >>x509.genkey "authorityKeyIdentifier=keyid"
-endif
-
-$(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: signing_key.x509
-
-signing_key.x509: scripts/extract-cert include/config/module/sig/key.h $(X509_DEP)
- $(call cmd,extract_certs,$(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY))
-endif