linux-stable/certs/Makefile
Masahiro Yamada b1992c3772 kbuild: use $(src) instead of $(srctree)/$(src) for source directory
Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:

    src := $(obj)

When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.

This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.

To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.

Going forward, the variables used in Makefiles will have the following
meanings:

  $(obj)     - directory in the object tree
  $(src)     - directory in the source tree  (changed by this commit)
  $(objtree) - the top of the kernel object tree
  $(srctree) - the top of the kernel source tree

Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2024-05-10 04:34:52 +09:00

88 lines
3.2 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
#
# Makefile for the linux kernel signature checking certificates.
#
obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o
obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist.o blacklist_hashes.o
obj-$(CONFIG_SYSTEM_REVOCATION_LIST) += revocation_certificates.o
$(obj)/blacklist_hashes.o: $(obj)/blacklist_hash_list
CFLAGS_blacklist_hashes.o := -I $(obj)
quiet_cmd_check_and_copy_blacklist_hash_list = GEN $@
cmd_check_and_copy_blacklist_hash_list = \
$(if $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST), \
$(AWK) -f $(src)/check-blacklist-hashes.awk $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST) >&2; \
{ cat $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST); echo $(comma) NULL; } > $@, \
echo NULL > $@)
$(obj)/blacklist_hash_list: $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST) FORCE
$(call if_changed,check_and_copy_blacklist_hash_list)
targets += blacklist_hash_list
quiet_cmd_extract_certs = CERT $@
cmd_extract_certs = $(obj)/extract-cert "$(extract-cert-in)" $@
extract-cert-in = $(filter-out $(obj)/extract-cert, $(real-prereqs))
$(obj)/system_certificates.o: $(obj)/x509_certificate_list
$(obj)/x509_certificate_list: $(CONFIG_SYSTEM_TRUSTED_KEYS) $(obj)/extract-cert FORCE
$(call if_changed,extract_certs)
targets += x509_certificate_list
# If module signing is requested, say by allyesconfig, but a key has not been
# supplied, then one will need to be generated to make sure the build does not
# fail and that the kernel may be used afterwards.
#
# We do it this way rather than having a boolean option for enabling an
# external private key, because 'make randconfig' might enable such a
# boolean option and we unfortunately can't make it depend on !RANDCONFIG.
ifeq ($(CONFIG_MODULE_SIG_KEY),certs/signing_key.pem)
keytype-$(CONFIG_MODULE_SIG_KEY_TYPE_ECDSA) := -newkey ec -pkeyopt ec_paramgen_curve:secp384r1
quiet_cmd_gen_key = GENKEY $@
cmd_gen_key = openssl req -new -nodes -utf8 -$(CONFIG_MODULE_SIG_HASH) -days 36500 \
-batch -x509 -config $< \
-outform PEM -out $@ -keyout $@ $(keytype-y) 2>&1
$(obj)/signing_key.pem: $(obj)/x509.genkey FORCE
$(call if_changed,gen_key)
targets += signing_key.pem
quiet_cmd_copy_x509_config = COPY $@
cmd_copy_x509_config = cat $(src)/default_x509.genkey > $@
# You can provide your own config file. If not present, copy the default one.
$(obj)/x509.genkey:
$(call cmd,copy_x509_config)
endif # CONFIG_MODULE_SIG_KEY
$(obj)/system_certificates.o: $(obj)/signing_key.x509
PKCS11_URI := $(filter pkcs11:%, $(CONFIG_MODULE_SIG_KEY))
ifdef PKCS11_URI
$(obj)/signing_key.x509: extract-cert-in := $(PKCS11_URI)
endif
$(obj)/signing_key.x509: $(filter-out $(PKCS11_URI),$(CONFIG_MODULE_SIG_KEY)) $(obj)/extract-cert FORCE
$(call if_changed,extract_certs)
targets += signing_key.x509
$(obj)/revocation_certificates.o: $(obj)/x509_revocation_list
$(obj)/x509_revocation_list: $(CONFIG_SYSTEM_REVOCATION_KEYS) $(obj)/extract-cert FORCE
$(call if_changed,extract_certs)
targets += x509_revocation_list
hostprogs := extract-cert
HOSTCFLAGS_extract-cert.o = $(shell $(HOSTPKG_CONFIG) --cflags libcrypto 2> /dev/null)
HOSTLDLIBS_extract-cert = $(shell $(HOSTPKG_CONFIG) --libs libcrypto 2> /dev/null || echo -lcrypto)