Merge tag 'certs-20220621' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull signature checking selftest from David Howells:
 "The signature checking code, as used by module signing, kexec, etc.,
  is non-FIPS compliant as there is no selftest.

  For a kernel to be FIPS-compliant, signature checking would have to be
  tested before being used, and the box would need to panic if it's not
  available (probably reasonable as simply disabling signature checking
  would prevent you from loading any driver modules).

  Deal with this by adding a minimal test.

  This is split into two patches: the first moves load_certificate_list()
  to the same place as the X.509 code to make it more accessible
  internally; the second adds a selftest"

* tag 'certs-20220621' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  certs: Add FIPS selftests
  certs: Move load_certificate_list() to be with the asymmetric keys code

certs/Makefile

@@ -3,8 +3,8 @@
 # Makefile for the linux kernel signature checking certificates.
 #
 
-obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o common.o
-obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist.o common.o
+obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o
+obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist.o
 obj-$(CONFIG_SYSTEM_REVOCATION_LIST) += revocation_certificates.o
 ifneq ($(CONFIG_SYSTEM_BLACKLIST_HASH_LIST),)
 

certs/blacklist.c

@@ -15,10 +15,9 @@
 #include <linux/err.h>
 #include <linux/seq_file.h>
 #include <linux/uidgid.h>
-#include <linux/verification.h>
+#include <keys/asymmetric-type.h>
 #include <keys/system_keyring.h>
 #include "blacklist.h"
-#include "common.h"
 
 /*
  * According to crypto/asymmetric_keys/x509_cert_parser.c:x509_note_pkey_algo(),
@@ -365,8 +364,9 @@ static __init int load_revocation_certificate_list(void)
 	if (revocation_certificate_list_size)
 		pr_notice("Loading compiled-in revocation X.509 certificates\n");
 
-	return load_certificate_list(revocation_certificate_list, revocation_certificate_list_size,
-				     blacklist_keyring);
+	return x509_load_certificate_list(revocation_certificate_list,
+					  revocation_certificate_list_size,
+					  blacklist_keyring);
 }
 late_initcall(load_revocation_certificate_list);
 #endif

certs/common.h

-/* SPDX-License-Identifier: GPL-2.0-or-later */
-
-#ifndef _CERT_COMMON_H
-#define _CERT_COMMON_H
-
-int load_certificate_list(const u8 cert_list[], const unsigned long list_size,
-			  const struct key *keyring);
-
-#endif

certs/system_keyring.c

@@ -16,7 +16,6 @@
 #include <keys/asymmetric-type.h>
 #include <keys/system_keyring.h>
 #include <crypto/pkcs7.h>
-#include "common.h"
 
 static struct key *builtin_trusted_keys;
 #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING
@@ -183,7 +182,8 @@ __init int load_module_cert(struct key *keyring)
 
 	pr_notice("Loading compiled-in module X.509 certificates\n");
 
-	return load_certificate_list(system_certificate_list, module_cert_size, keyring);
+	return x509_load_certificate_list(system_certificate_list,
+					  module_cert_size, keyring);
 }
 
 /*
@@ -204,7 +204,7 @@ static __init int load_system_certificate_list(void)
 	size = system_certificate_list_size - module_cert_size;
 #endif
 
-	return load_certificate_list(p, size, builtin_trusted_keys);
+	return x509_load_certificate_list(p, size, builtin_trusted_keys);
 }
 late_initcall(load_system_certificate_list);
 

crypto/asymmetric_keys/Kconfig

@@ -75,4 +75,14 @@ config SIGNED_PE_FILE_VERIFICATION
 	  This option provides support for verifying the signature(s) on a
 	  signed PE binary.
 
+config FIPS_SIGNATURE_SELFTEST
+	bool "Run FIPS selftests on the X.509+PKCS7 signature verification"
+	help
+	  This option causes some selftests to be run on the signature
+	  verification code, using some built in data.  This is required
+	  for FIPS.
+	depends on KEYS
+	depends on ASYMMETRIC_KEY_TYPE
+	depends on PKCS7_MESSAGE_PARSER
+
 endif # ASYMMETRIC_KEY_TYPE

crypto/asymmetric_keys/Makefile

@@ -20,7 +20,9 @@ x509_key_parser-y := \
 	x509.asn1.o \
 	x509_akid.asn1.o \
 	x509_cert_parser.o \
+	x509_loader.o \
 	x509_public_key.o
+x509_key_parser-$(CONFIG_FIPS_SIGNATURE_SELFTEST) += selftest.o
 
 $(obj)/x509_cert_parser.o: \
 	$(obj)/x509.asn1.h \

certs/common.c → crypto/asymmetric_keys/x509_loader.c

@@ -2,11 +2,11 @@
 
 #include <linux/kernel.h>
 #include <linux/key.h>
-#include "common.h"
+#include <keys/asymmetric-type.h>
 
-int load_certificate_list(const u8 cert_list[],
-			  const unsigned long list_size,
-			  const struct key *keyring)
+int x509_load_certificate_list(const u8 cert_list[],
+			       const unsigned long list_size,
+			       const struct key *keyring)
 {
 	key_ref_t key;
 	const u8 *p, *end;

crypto/asymmetric_keys/x509_parser.h

@@ -40,6 +40,15 @@ struct x509_certificate {
 	bool		blacklisted;
 };
 
+/*
+ * selftest.c
+ */
+#ifdef CONFIG_FIPS_SIGNATURE_SELFTEST
+extern int __init fips_signature_selftest(void);
+#else
+static inline int fips_signature_selftest(void) { return 0; }
+#endif
+
 /*
  * x509_cert_parser.c
  */

crypto/asymmetric_keys/x509_public_key.c

@@ -244,9 +244,15 @@ static struct asymmetric_key_parser x509_key_parser = {
 /*
  * Module stuff
  */
+extern int __init certs_selftest(void);
 static int __init x509_key_init(void)
 {
-	return register_asymmetric_key_parser(&x509_key_parser);
+	int ret;
+
+	ret = register_asymmetric_key_parser(&x509_key_parser);
+	if (ret < 0)
+		return ret;
+	return fips_signature_selftest();
 }
 
 static void __exit x509_key_exit(void)

include/keys/asymmetric-type.h

@@ -84,6 +84,9 @@ extern struct key *find_asymmetric_key(struct key *keyring,
 				       const struct asymmetric_key_id *id_2,
 				       bool partial);
 
+int x509_load_certificate_list(const u8 cert_list[], const unsigned long list_size,
+			       const struct key *keyring);
+
 /*
  * The payload is at the discretion of the subtype.
  */