diff options
| -rw-r--r-- | include/keys/system_keyring.h | 23 | ||||
| -rw-r--r-- | init/Kconfig | 13 | ||||
| -rw-r--r-- | kernel/Makefile | 15 | ||||
| -rw-r--r-- | kernel/modsign_pubkey.c | 104 | ||||
| -rw-r--r-- | kernel/module-internal.h | 2 | ||||
| -rw-r--r-- | kernel/module_signing.c | 3 | ||||
| -rw-r--r-- | kernel/system_certificates.S (renamed from kernel/modsign_certificate.S) | 7 | ||||
| -rw-r--r-- | kernel/system_keyring.c | 103 |
8 files changed, 155 insertions, 115 deletions
diff --git a/include/keys/system_keyring.h b/include/keys/system_keyring.h new file mode 100644 index 000000000000..8dabc399bd1d --- /dev/null +++ b/include/keys/system_keyring.h @@ -0,0 +1,23 @@ +/* System keyring containing trusted public keys. + * + * Copyright (C) 2013 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#ifndef _KEYS_SYSTEM_KEYRING_H +#define _KEYS_SYSTEM_KEYRING_H + +#ifdef CONFIG_SYSTEM_TRUSTED_KEYRING + +#include <linux/key.h> + +extern struct key *system_trusted_keyring; + +#endif + +#endif /* _KEYS_SYSTEM_KEYRING_H */ diff --git a/init/Kconfig b/init/Kconfig index 3ecd8a1178f1..0ff5407a8378 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1668,6 +1668,18 @@ config BASE_SMALL default 0 if BASE_FULL default 1 if !BASE_FULL +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. + menuconfig MODULES bool "Enable loadable module support" option modules @@ -1741,6 +1753,7 @@ config MODULE_SRCVERSION_ALL config MODULE_SIG bool "Module signature verification" depends on MODULES + select SYSTEM_TRUSTED_KEYRING select KEYS select CRYPTO select ASYMMETRIC_KEY_TYPE diff --git a/kernel/Makefile b/kernel/Makefile index 2c24195249d5..63136989c132 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -54,8 +54,9 @@ obj-$(CONFIG_SMP) += spinlock.o obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o obj-$(CONFIG_PROVE_LOCKING) += spinlock.o obj-$(CONFIG_UID16) += uid16.o +obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o obj-$(CONFIG_MODULES) += module.o -obj-$(CONFIG_MODULE_SIG) += module_signing.o modsign_pubkey.o modsign_certificate.o +obj-$(CONFIG_MODULE_SIG) += module_signing.o obj-$(CONFIG_KALLSYMS) += kallsyms.o obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o obj-$(CONFIG_KEXEC) += kexec.o @@ -141,11 +142,11 @@ targets += timeconst.h $(obj)/timeconst.h: $(obj)/hz.bc $(src)/timeconst.bc FORCE $(call if_changed,bc) -ifeq ($(CONFIG_MODULE_SIG),y) ############################################################################### # # Roll all the X.509 certificates that we can find together and pull them into -# the kernel. +# the kernel so that they get loaded into the system trusted keyring during +# boot. # # We look in the source root and the build root for all files whose name ends # in ".x509". Unfortunately, this will generate duplicate filenames, so we @@ -153,6 +154,7 @@ ifeq ($(CONFIG_MODULE_SIG),y) # duplicates. # ############################################################################### +ifeq ($(CONFIG_SYSTEM_TRUSTED_KEYRING),y) X509_CERTIFICATES-y := $(wildcard *.x509) $(wildcard $(srctree)/*.x509) X509_CERTIFICATES-$(CONFIG_MODULE_SIG) += signing_key.x509 X509_CERTIFICATES := $(sort $(foreach CERT,$(X509_CERTIFICATES-y), \ @@ -169,10 +171,11 @@ $(shell rm $(obj)/.x509.list) endif endif -kernel/modsign_certificate.o: $(obj)/x509_certificate_list +kernel/system_certificates.o: $(obj)/x509_certificate_list quiet_cmd_x509certs = CERTS $@ - cmd_x509certs = cat $(X509_CERTIFICATES) /dev/null >$@ + cmd_x509certs = cat $(X509_CERTIFICATES) /dev/null >$@ $(foreach X509,$(X509_CERTIFICATES),; echo " - Including cert $(X509)") + targets += $(obj)/x509_certificate_list $(obj)/x509_certificate_list: $(X509_CERTIFICATES) $(obj)/.x509.list $(call if_changed,x509certs) @@ -182,7 +185,9 @@ $(obj)/.x509.list: @echo $(X509_CERTIFICATES) >$@ clean-files := x509_certificate_list .x509.list +endif +ifeq ($(CONFIG_MODULE_SIG),y) ############################################################################### # # If module signing is requested, say by allyesconfig, but a key has not been diff --git a/kernel/modsign_pubkey.c b/kernel/modsign_pubkey.c deleted file mode 100644 index 7cbd4507a7e6..000000000000 --- a/kernel/modsign_pubkey.c +++ /dev/null @@ -1,104 +0,0 @@ -/* Public keys for module signature verification - * - * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public Licence - * as published by the Free Software Foundation; either version - * 2 of the Licence, or (at your option) any later version. - */ - -#include <linux/kernel.h> -#include <linux/sched.h> -#include <linux/cred.h> -#include <linux/err.h> -#include <keys/asymmetric-type.h> -#include "module-internal.h" - -struct key *modsign_keyring; - -extern __initconst const u8 modsign_certificate_list[]; -extern __initconst const u8 modsign_certificate_list_end[]; - -/* - * We need to make sure ccache doesn't cache the .o file as it doesn't notice - * if modsign.pub changes. - */ -static __initconst const char annoy_ccache[] = __TIME__ "foo"; - -/* - * Load the compiled-in keys - */ -static __init int module_verify_init(void) -{ - pr_notice("Initialise module verification\n"); - - modsign_keyring = keyring_alloc(".module_sign", - KUIDT_INIT(0), KGIDT_INIT(0), - current_cred(), - ((KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ), - KEY_ALLOC_NOT_IN_QUOTA, NULL); - if (IS_ERR(modsign_keyring)) - panic("Can't allocate module signing keyring\n"); - - return 0; -} - -/* - * Must be initialised before we try and load the keys into the keyring. - */ -device_initcall(module_verify_init); - -/* - * Load the compiled-in keys - */ -static __init int load_module_signing_keys(void) -{ - key_ref_t key; - const u8 *p, *end; - size_t plen; - - pr_notice("Loading module verification certificates\n"); - - end = modsign_certificate_list_end; - p = modsign_certificate_list; - while (p < end) { - /* Each cert begins with an ASN.1 SEQUENCE tag and must be more - * than 256 bytes in size. - */ - if (end - p < 4) - goto dodgy_cert; - if (p[0] != 0x30 && - p[1] != 0x82) - goto dodgy_cert; - plen = (p[2] << 8) | p[3]; - plen += 4; - if (plen > end - p) - goto dodgy_cert; - - key = key_create_or_update(make_key_ref(modsign_keyring, 1), - "asymmetric", - NULL, - p, - plen, - (KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW, - KEY_ALLOC_NOT_IN_QUOTA); - if (IS_ERR(key)) - pr_err("MODSIGN: Problem loading in-kernel X.509 certificate (%ld)\n", - PTR_ERR(key)); - else - pr_notice("MODSIGN: Loaded cert '%s'\n", - key_ref_to_ptr(key)->description); - p += plen; - } - - return 0; - -dodgy_cert: - pr_err("MODSIGN: Problem parsing in-kernel X.509 certificate list\n"); - return 0; -} -late_initcall(load_module_signing_keys); diff --git a/kernel/module-internal.h b/kernel/module-internal.h index 24f9247b7d02..915e123a430f 100644 --- a/kernel/module-internal.h +++ b/kernel/module-internal.h @@ -9,6 +9,4 @@ * 2 of the Licence, or (at your option) any later version. */ -extern struct key *modsign_keyring; - extern int mod_verify_sig(const void *mod, unsigned long *_modlen); diff --git a/kernel/module_signing.c b/kernel/module_signing.c index ee476404167b..0b6b870dc5e4 100644 --- a/kernel/module_signing.c +++ b/kernel/module_signing.c @@ -14,6 +14,7 @@ #include <crypto/public_key.h> #include <crypto/hash.h> #include <keys/asymmetric-type.h> +#include <keys/system_keyring.h> #include "module-internal.h" /* @@ -157,7 +158,7 @@ static struct key *request_asymmetric_key(const char *signer, size_t signer_len, pr_debug("Look up: \"%s\"\n", id); - key = keyring_search(make_key_ref(modsign_keyring, 1), + key = keyring_search(make_key_ref(system_trusted_keyring, 1), &key_type_asymmetric, id); if (IS_ERR(key)) pr_warn("Request for unknown module key '%s' err %ld\n", diff --git a/kernel/modsign_certificate.S b/kernel/system_certificates.S index 6fe03c7ffe72..552d47b2d463 100644 --- a/kernel/modsign_certificate.S +++ b/kernel/system_certificates.S @@ -1,11 +1,12 @@ #include <linux/export.h> +#include <linux/init.h> #define GLOBAL(name) \ .globl VMLINUX_SYMBOL(name); \ VMLINUX_SYMBOL(name): - .section ".init.data","aw" + __INITRODATA -GLOBAL(modsign_certificate_list) +GLOBAL(system_certificate_list) .incbin "kernel/x509_certificate_list" -GLOBAL(modsign_certificate_list_end) +GLOBAL(system_certificate_list_end) diff --git a/kernel/system_keyring.c b/kernel/system_keyring.c new file mode 100644 index 000000000000..51c35141a13a --- /dev/null +++ b/kernel/system_keyring.c @@ -0,0 +1,103 @@ +/* System trusted keyring for trusted public keys + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#include <linux/export.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/cred.h> +#include <linux/err.h> +#include <keys/asymmetric-type.h> +#include <keys/system_keyring.h> +#include "module-internal.h" + +struct key *system_trusted_keyring; +EXPORT_SYMBOL_GPL(system_trusted_keyring); + +extern __initconst const u8 system_certificate_list[]; +extern __initconst const u8 system_certificate_list_end[]; + +/* + * Load the compiled-in keys + */ +static __init int system_trusted_keyring_init(void) +{ + pr_notice("Initialise system trusted keyring\n"); + + system_trusted_keyring = + keyring_alloc(".system_keyring", + KUIDT_INIT(0), KGIDT_INIT(0), current_cred(), + ((KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW | KEY_USR_READ), + KEY_ALLOC_NOT_IN_QUOTA, NULL); + if (IS_ERR(system_trusted_keyring)) + panic("Can't allocate system trusted keyring\n"); + + return 0; +} + +/* + * Must be initialised before we try and load the keys into the keyring. + */ +device_initcall(system_trusted_keyring_init); + +/* + * Load the compiled-in list of X.509 certificates. + */ +static __init int load_system_certificate_list(void) +{ + key_ref_t key; + const u8 *p, *end; + size_t plen; + + pr_notice("Loading compiled-in X.509 certificates\n"); + + end = system_certificate_list_end; + p = system_certificate_list; + while (p < end) { + /* Each cert begins with an ASN.1 SEQUENCE tag and must be more + * than 256 bytes in size. + */ + if (end - p < 4) + goto dodgy_cert; + if (p[0] != 0x30 && + p[1] != 0x82) + goto dodgy_cert; + plen = (p[2] << 8) | p[3]; + plen += 4; + if (plen > end - p) + goto dodgy_cert; + + key = key_create_or_update(make_key_ref(system_trusted_keyring, 1), + "asymmetric", + NULL, + p, + plen, + (KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW, + KEY_ALLOC_NOT_IN_QUOTA); + if (IS_ERR(key)) { + pr_err("Problem loading in-kernel X.509 certificate (%ld)\n", + PTR_ERR(key)); + } else { + pr_notice("Loaded X.509 cert '%s'\n", + key_ref_to_ptr(key)->description); + key_ref_put(key); + } + p += plen; + } + + return 0; + +dodgy_cert: + pr_err("Problem parsing in-kernel X.509 certificate list\n"); + return 0; +} +late_initcall(load_system_certificate_list); |