xref: /linux/certs/Makefile (revision f3a2ba44e93e2c192a872f2705fe66dbf39708d6)
1# SPDX-License-Identifier: GPL-2.0
2#
3# Makefile for the linux kernel signature checking certificates.
4#
5
6obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o common.o
7obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist.o common.o
8obj-$(CONFIG_SYSTEM_REVOCATION_LIST) += revocation_certificates.o
9ifneq ($(CONFIG_SYSTEM_BLACKLIST_HASH_LIST),"")
10obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist_hashes.o
11else
12obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist_nohashes.o
13endif
14
15ifeq ($(CONFIG_SYSTEM_TRUSTED_KEYRING),y)
16
17$(eval $(call config_filename,SYSTEM_TRUSTED_KEYS))
18
19# GCC doesn't include .incbin files in -MD generated dependencies (PR#66871)
20$(obj)/system_certificates.o: $(obj)/x509_certificate_list
21
22# Cope with signing_key.x509 existing in $(srctree) not $(objtree)
23AFLAGS_system_certificates.o := -I$(srctree)
24
25quiet_cmd_extract_certs  = EXTRACT_CERTS   $(patsubst "%",%,$(2))
26      cmd_extract_certs  = scripts/extract-cert $(2) $@
27
28targets += x509_certificate_list
29$(obj)/x509_certificate_list: scripts/extract-cert $(SYSTEM_TRUSTED_KEYS_SRCPREFIX)$(SYSTEM_TRUSTED_KEYS_FILENAME) FORCE
30	$(call if_changed,extract_certs,$(SYSTEM_TRUSTED_KEYS_SRCPREFIX)$(CONFIG_SYSTEM_TRUSTED_KEYS))
31endif # CONFIG_SYSTEM_TRUSTED_KEYRING
32
33clean-files := x509_certificate_list .x509.list x509_revocation_list
34
35ifeq ($(CONFIG_MODULE_SIG),y)
36	SIGN_KEY = y
37endif
38
39ifeq ($(CONFIG_IMA_APPRAISE_MODSIG),y)
40ifeq ($(CONFIG_MODULES),y)
41	SIGN_KEY = y
42endif
43endif
44
45ifdef SIGN_KEY
46###############################################################################
47#
48# If module signing is requested, say by allyesconfig, but a key has not been
49# supplied, then one will need to be generated to make sure the build does not
50# fail and that the kernel may be used afterwards.
51#
52###############################################################################
53
54redirect_openssl	= 2>&1
55quiet_redirect_openssl	= 2>&1
56silent_redirect_openssl = 2>/dev/null
57openssl_available       = $(shell openssl help 2>/dev/null && echo yes)
58
59# We do it this way rather than having a boolean option for enabling an
60# external private key, because 'make randconfig' might enable such a
61# boolean option and we unfortunately can't make it depend on !RANDCONFIG.
62ifeq ($(CONFIG_MODULE_SIG_KEY),"certs/signing_key.pem")
63
64ifeq ($(openssl_available),yes)
65X509TEXT=$(shell openssl x509 -in "certs/signing_key.pem" -text 2>/dev/null)
66endif
67
68# Support user changing key type
69ifdef CONFIG_MODULE_SIG_KEY_TYPE_ECDSA
70keytype_openssl = -newkey ec -pkeyopt ec_paramgen_curve:secp384r1
71ifeq ($(openssl_available),yes)
72$(if $(findstring id-ecPublicKey,$(X509TEXT)),,$(shell rm -f "certs/signing_key.pem"))
73endif
74endif # CONFIG_MODULE_SIG_KEY_TYPE_ECDSA
75
76ifdef CONFIG_MODULE_SIG_KEY_TYPE_RSA
77ifeq ($(openssl_available),yes)
78$(if $(findstring rsaEncryption,$(X509TEXT)),,$(shell rm -f "certs/signing_key.pem"))
79endif
80endif # CONFIG_MODULE_SIG_KEY_TYPE_RSA
81
82$(obj)/signing_key.pem: $(obj)/x509.genkey
83	@$(kecho) "###"
84	@$(kecho) "### Now generating an X.509 key pair to be used for signing modules."
85	@$(kecho) "###"
86	@$(kecho) "### If this takes a long time, you might wish to run rngd in the"
87	@$(kecho) "### background to keep the supply of entropy topped up.  It"
88	@$(kecho) "### needs to be run as root, and uses a hardware random"
89	@$(kecho) "### number generator if one is available."
90	@$(kecho) "###"
91	$(Q)openssl req -new -nodes -utf8 -$(CONFIG_MODULE_SIG_HASH) -days 36500 \
92		-batch -x509 -config $(obj)/x509.genkey \
93		-outform PEM -out $(obj)/signing_key.pem \
94		-keyout $(obj)/signing_key.pem \
95		$(keytype_openssl) \
96		$($(quiet)redirect_openssl)
97	@$(kecho) "###"
98	@$(kecho) "### Key pair generated."
99	@$(kecho) "###"
100
101quiet_cmd_copy_x509_config = COPY    $@
102      cmd_copy_x509_config = cat $(srctree)/$(src)/default_x509.genkey > $@
103
104# You can provide your own config file. If not present, copy the default one.
105$(obj)/x509.genkey:
106	$(call cmd,copy_x509_config)
107
108endif # CONFIG_MODULE_SIG_KEY
109
110$(eval $(call config_filename,MODULE_SIG_KEY))
111
112# If CONFIG_MODULE_SIG_KEY isn't a PKCS#11 URI, depend on it
113ifeq ($(patsubst pkcs11:%,%,$(firstword $(MODULE_SIG_KEY_FILENAME))),$(firstword $(MODULE_SIG_KEY_FILENAME)))
114X509_DEP := $(MODULE_SIG_KEY_SRCPREFIX)$(MODULE_SIG_KEY_FILENAME)
115endif
116
117# GCC PR#66871 again.
118$(obj)/system_certificates.o: $(obj)/signing_key.x509
119
120targets += signing_key.x509
121$(obj)/signing_key.x509: scripts/extract-cert $(X509_DEP) FORCE
122	$(call if_changed,extract_certs,$(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY))
123endif # CONFIG_MODULE_SIG
124
125ifeq ($(CONFIG_SYSTEM_REVOCATION_LIST),y)
126
127$(eval $(call config_filename,SYSTEM_REVOCATION_KEYS))
128
129$(obj)/revocation_certificates.o: $(obj)/x509_revocation_list
130
131quiet_cmd_extract_certs  = EXTRACT_CERTS   $(patsubst "%",%,$(2))
132      cmd_extract_certs  = scripts/extract-cert $(2) $@
133
134targets += x509_revocation_list
135$(obj)/x509_revocation_list: scripts/extract-cert $(SYSTEM_REVOCATION_KEYS_SRCPREFIX)$(SYSTEM_REVOCATION_KEYS_FILENAME) FORCE
136	$(call if_changed,extract_certs,$(SYSTEM_REVOCATION_KEYS_SRCPREFIX)$(CONFIG_SYSTEM_REVOCATION_KEYS))
137endif
138