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1# SPDX-License-Identifier: GPL-2.0
2#
3# Makefile for the linux kernel signature checking certificates.
4#
5
6obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o
7obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist.o blacklist_hashes.o
8obj-$(CONFIG_SYSTEM_REVOCATION_LIST) += revocation_certificates.o
9
10$(obj)/blacklist_hashes.o: $(obj)/blacklist_hash_list
11CFLAGS_blacklist_hashes.o := -I $(obj)
12
13quiet_cmd_check_and_copy_blacklist_hash_list = GEN $@
14 cmd_check_and_copy_blacklist_hash_list = \
15 $(if $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST), \
16 $(AWK) -f $(srctree)/$(src)/check-blacklist-hashes.awk $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST) >&2; \
17 { cat $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST); echo $(comma) NULL; } > $@, \
18 echo NULL > $@)
19
20$(obj)/blacklist_hash_list: $(CONFIG_SYSTEM_BLACKLIST_HASH_LIST) FORCE
21 $(call if_changed,check_and_copy_blacklist_hash_list)
22
23targets += blacklist_hash_list
24
25quiet_cmd_extract_certs = CERT $@
26 cmd_extract_certs = $(obj)/extract-cert "$(extract-cert-in)" $@
27extract-cert-in = $(filter-out $(obj)/extract-cert, $(real-prereqs))
28
29$(obj)/system_certificates.o: $(obj)/x509_certificate_list
30
31$(obj)/x509_certificate_list: $(CONFIG_SYSTEM_TRUSTED_KEYS) $(obj)/extract-cert FORCE
32 $(call if_changed,extract_certs)
33
34targets += x509_certificate_list
35
36# If module signing is requested, say by allyesconfig, but a key has not been
37# supplied, then one will need to be generated to make sure the build does not
38# fail and that the kernel may be used afterwards.
39#
40# We do it this way rather than having a boolean option for enabling an
41# external private key, because 'make randconfig' might enable such a
42# boolean option and we unfortunately can't make it depend on !RANDCONFIG.
43ifeq ($(CONFIG_MODULE_SIG_KEY),certs/signing_key.pem)
44
45keytype-$(CONFIG_MODULE_SIG_KEY_TYPE_ECDSA) := -newkey ec -pkeyopt ec_paramgen_curve:secp384r1
46
47quiet_cmd_gen_key = GENKEY $@
48 cmd_gen_key = openssl req -new -nodes -utf8 -$(CONFIG_MODULE_SIG_HASH) -days 36500 \
49 -batch -x509 -config $< \
50 -outform PEM -out $@ -keyout $@ $(keytype-y) 2>&1
51
52$(obj)/signing_key.pem: $(obj)/x509.genkey FORCE
53 $(call if_changed,gen_key)
54
55targets += signing_key.pem
56
57quiet_cmd_copy_x509_config = COPY $@
58 cmd_copy_x509_config = cat $(srctree)/$(src)/default_x509.genkey > $@
59
60# You can provide your own config file. If not present, copy the default one.
61$(obj)/x509.genkey:
62 $(call cmd,copy_x509_config)
63
64endif # CONFIG_MODULE_SIG_KEY
65
66$(obj)/system_certificates.o: $(obj)/signing_key.x509
67
68PKCS11_URI := $(filter pkcs11:%, $(CONFIG_MODULE_SIG_KEY))
69ifdef PKCS11_URI
70$(obj)/signing_key.x509: extract-cert-in := $(PKCS11_URI)
71endif
72
73$(obj)/signing_key.x509: $(filter-out $(PKCS11_URI),$(CONFIG_MODULE_SIG_KEY)) $(obj)/extract-cert FORCE
74 $(call if_changed,extract_certs)
75
76targets += signing_key.x509
77
78$(obj)/revocation_certificates.o: $(obj)/x509_revocation_list
79
80$(obj)/x509_revocation_list: $(CONFIG_SYSTEM_REVOCATION_KEYS) $(obj)/extract-cert FORCE
81 $(call if_changed,extract_certs)
82
83targets += x509_revocation_list
84
85hostprogs := extract-cert
86
87HOSTCFLAGS_extract-cert.o = $(shell $(HOSTPKG_CONFIG) --cflags libcrypto 2> /dev/null)
88HOSTLDLIBS_extract-cert = $(shell $(HOSTPKG_CONFIG) --libs libcrypto 2> /dev/null || echo -lcrypto)
1#
2# Makefile for the linux kernel signature checking certificates.
3#
4
5obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o
6
7ifeq ($(CONFIG_SYSTEM_TRUSTED_KEYRING),y)
8
9$(eval $(call config_filename,SYSTEM_TRUSTED_KEYS))
10
11# GCC doesn't include .incbin files in -MD generated dependencies (PR#66871)
12$(obj)/system_certificates.o: $(obj)/x509_certificate_list
13
14# Cope with signing_key.x509 existing in $(srctree) not $(objtree)
15AFLAGS_system_certificates.o := -I$(srctree)
16
17quiet_cmd_extract_certs = EXTRACT_CERTS $(patsubst "%",%,$(2))
18 cmd_extract_certs = scripts/extract-cert $(2) $@ || ( rm $@; exit 1)
19
20targets += x509_certificate_list
21$(obj)/x509_certificate_list: scripts/extract-cert $(SYSTEM_TRUSTED_KEYS_SRCPREFIX)$(SYSTEM_TRUSTED_KEYS_FILENAME) FORCE
22 $(call if_changed,extract_certs,$(SYSTEM_TRUSTED_KEYS_SRCPREFIX)$(CONFIG_SYSTEM_TRUSTED_KEYS))
23endif
24
25clean-files := x509_certificate_list .x509.list
26
27ifeq ($(CONFIG_MODULE_SIG),y)
28###############################################################################
29#
30# If module signing is requested, say by allyesconfig, but a key has not been
31# supplied, then one will need to be generated to make sure the build does not
32# fail and that the kernel may be used afterwards.
33#
34###############################################################################
35ifndef CONFIG_MODULE_SIG_HASH
36$(error Could not determine digest type to use from kernel config)
37endif
38
39redirect_openssl = 2>&1
40quiet_redirect_openssl = 2>&1
41silent_redirect_openssl = 2>/dev/null
42
43# We do it this way rather than having a boolean option for enabling an
44# external private key, because 'make randconfig' might enable such a
45# boolean option and we unfortunately can't make it depend on !RANDCONFIG.
46ifeq ($(CONFIG_MODULE_SIG_KEY),"certs/signing_key.pem")
47$(obj)/signing_key.pem: $(obj)/x509.genkey
48 @$(kecho) "###"
49 @$(kecho) "### Now generating an X.509 key pair to be used for signing modules."
50 @$(kecho) "###"
51 @$(kecho) "### If this takes a long time, you might wish to run rngd in the"
52 @$(kecho) "### background to keep the supply of entropy topped up. It"
53 @$(kecho) "### needs to be run as root, and uses a hardware random"
54 @$(kecho) "### number generator if one is available."
55 @$(kecho) "###"
56 $(Q)openssl req -new -nodes -utf8 -$(CONFIG_MODULE_SIG_HASH) -days 36500 \
57 -batch -x509 -config $(obj)/x509.genkey \
58 -outform PEM -out $(obj)/signing_key.pem \
59 -keyout $(obj)/signing_key.pem \
60 $($(quiet)redirect_openssl)
61 @$(kecho) "###"
62 @$(kecho) "### Key pair generated."
63 @$(kecho) "###"
64
65$(obj)/x509.genkey:
66 @$(kecho) Generating X.509 key generation config
67 @echo >$@ "[ req ]"
68 @echo >>$@ "default_bits = 4096"
69 @echo >>$@ "distinguished_name = req_distinguished_name"
70 @echo >>$@ "prompt = no"
71 @echo >>$@ "string_mask = utf8only"
72 @echo >>$@ "x509_extensions = myexts"
73 @echo >>$@
74 @echo >>$@ "[ req_distinguished_name ]"
75 @echo >>$@ "#O = Unspecified company"
76 @echo >>$@ "CN = Build time autogenerated kernel key"
77 @echo >>$@ "#emailAddress = unspecified.user@unspecified.company"
78 @echo >>$@
79 @echo >>$@ "[ myexts ]"
80 @echo >>$@ "basicConstraints=critical,CA:FALSE"
81 @echo >>$@ "keyUsage=digitalSignature"
82 @echo >>$@ "subjectKeyIdentifier=hash"
83 @echo >>$@ "authorityKeyIdentifier=keyid"
84endif
85
86$(eval $(call config_filename,MODULE_SIG_KEY))
87
88# If CONFIG_MODULE_SIG_KEY isn't a PKCS#11 URI, depend on it
89ifeq ($(patsubst pkcs11:%,%,$(firstword $(MODULE_SIG_KEY_FILENAME))),$(firstword $(MODULE_SIG_KEY_FILENAME)))
90X509_DEP := $(MODULE_SIG_KEY_SRCPREFIX)$(MODULE_SIG_KEY_FILENAME)
91endif
92
93# GCC PR#66871 again.
94$(obj)/system_certificates.o: $(obj)/signing_key.x509
95
96targets += signing_key.x509
97$(obj)/signing_key.x509: scripts/extract-cert $(X509_DEP) FORCE
98 $(call if_changed,extract_certs,$(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY))
99endif