diff options
Diffstat (limited to 'certs')
| -rw-r--r-- | certs/Kconfig | 9 | ||||
| -rw-r--r-- | certs/Makefile | 10 | ||||
| -rw-r--r-- | certs/blacklist.c | 54 | ||||
| -rw-r--r-- | certs/blacklist.h | 2 | ||||
| -rw-r--r-- | certs/blacklist_hashes.c | 2 | ||||
| -rw-r--r-- | certs/common.c | 57 | ||||
| -rw-r--r-- | certs/common.h | 9 | ||||
| -rw-r--r-- | certs/system_keyring.c | 55 |
8 files changed, 149 insertions, 49 deletions
diff --git a/certs/Kconfig b/certs/Kconfig index c94e93d8bccf..76e469b56a77 100644 --- a/certs/Kconfig +++ b/certs/Kconfig @@ -83,4 +83,13 @@ config SYSTEM_BLACKLIST_HASH_LIST wrapper to incorporate the list into the kernel. Each <hash> should be a string of hex digits. +config SYSTEM_REVOCATION_LIST + bool "Provide system-wide ring of revocation certificates" + depends on SYSTEM_BLACKLIST_KEYRING + depends on PKCS7_MESSAGE_PARSER=y + help + If set, this allows revocation certificates to be stored in the + blacklist keyring and implements a hook whereby a PKCS#7 message can + be checked to see if it matches such a certificate. + endmenu diff --git a/certs/Makefile b/certs/Makefile index f4c25b67aad9..2baef6fba029 100644 --- a/certs/Makefile +++ b/certs/Makefile @@ -3,7 +3,7 @@ # Makefile for the linux kernel signature checking certificates. # -obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o +obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o common.o obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist.o ifneq ($(CONFIG_SYSTEM_BLACKLIST_HASH_LIST),"") obj-$(CONFIG_SYSTEM_BLACKLIST_KEYRING) += blacklist_hashes.o @@ -46,11 +46,19 @@ endif redirect_openssl = 2>&1 quiet_redirect_openssl = 2>&1 silent_redirect_openssl = 2>/dev/null +openssl_available = $(shell openssl help 2>/dev/null && echo yes) # We do it this way rather than having a boolean option for enabling an # external private key, because 'make randconfig' might enable such a # boolean option and we unfortunately can't make it depend on !RANDCONFIG. ifeq ($(CONFIG_MODULE_SIG_KEY),"certs/signing_key.pem") + +ifeq ($(openssl_available),yes) +X509TEXT=$(shell openssl x509 -in "certs/signing_key.pem" -text 2>/dev/null) + +$(if $(findstring rsaEncryption,$(X509TEXT)),,$(shell rm -f "certs/signing_key.pem")) +endif + $(obj)/signing_key.pem: $(obj)/x509.genkey @$(kecho) "###" @$(kecho) "### Now generating an X.509 key pair to be used for signing modules." diff --git a/certs/blacklist.c b/certs/blacklist.c index ec00bf337eb6..59b2f106b294 100644 --- a/certs/blacklist.c +++ b/certs/blacklist.c @@ -135,6 +135,58 @@ int is_hash_blacklisted(const u8 *hash, size_t hash_len, const char *type) } EXPORT_SYMBOL_GPL(is_hash_blacklisted); +int is_binary_blacklisted(const u8 *hash, size_t hash_len) +{ + if (is_hash_blacklisted(hash, hash_len, "bin") == -EKEYREJECTED) + return -EPERM; + + return 0; +} +EXPORT_SYMBOL_GPL(is_binary_blacklisted); + +#ifdef CONFIG_SYSTEM_REVOCATION_LIST +/** + * add_key_to_revocation_list - Add a revocation certificate to the blacklist + * @data: The data blob containing the certificate + * @size: The size of data blob + */ +int add_key_to_revocation_list(const char *data, size_t size) +{ + key_ref_t key; + + key = key_create_or_update(make_key_ref(blacklist_keyring, true), + "asymmetric", + NULL, + data, + size, + ((KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW), + KEY_ALLOC_NOT_IN_QUOTA | KEY_ALLOC_BUILT_IN); + + if (IS_ERR(key)) { + pr_err("Problem with revocation key (%ld)\n", PTR_ERR(key)); + return PTR_ERR(key); + } + + return 0; +} + +/** + * is_key_on_revocation_list - Determine if the key for a PKCS#7 message is revoked + * @pkcs7: The PKCS#7 message to check + */ +int is_key_on_revocation_list(struct pkcs7_message *pkcs7) +{ + int ret; + + ret = pkcs7_validate_trust(pkcs7, blacklist_keyring); + + if (ret == 0) + return -EKEYREJECTED; + + return -ENOKEY; +} +#endif + /* * Initialise the blacklist */ @@ -153,7 +205,7 @@ static int __init blacklist_init(void) KEY_USR_VIEW | KEY_USR_READ | KEY_USR_SEARCH, KEY_ALLOC_NOT_IN_QUOTA | - KEY_FLAG_KEEP, + KEY_ALLOC_SET_KEEP, NULL, NULL); if (IS_ERR(blacklist_keyring)) panic("Can't allocate system blacklist keyring\n"); diff --git a/certs/blacklist.h b/certs/blacklist.h index 1efd6fa0dc60..51b320cf8574 100644 --- a/certs/blacklist.h +++ b/certs/blacklist.h @@ -1,3 +1,5 @@ #include <linux/kernel.h> +#include <linux/errno.h> +#include <crypto/pkcs7.h> extern const char __initconst *const blacklist_hashes[]; diff --git a/certs/blacklist_hashes.c b/certs/blacklist_hashes.c index 344892337be0..d5961aa3d338 100644 --- a/certs/blacklist_hashes.c +++ b/certs/blacklist_hashes.c @@ -1,7 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 #include "blacklist.h" -const char __initdata *const blacklist_hashes[] = { +const char __initconst *const blacklist_hashes[] = { #include CONFIG_SYSTEM_BLACKLIST_HASH_LIST , NULL }; diff --git a/certs/common.c b/certs/common.c new file mode 100644 index 000000000000..16a220887a53 --- /dev/null +++ b/certs/common.c @@ -0,0 +1,57 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/kernel.h> +#include <linux/key.h> +#include "common.h" + +int load_certificate_list(const u8 cert_list[], + const unsigned long list_size, + const struct key *keyring) +{ + key_ref_t key; + const u8 *p, *end; + size_t plen; + + p = cert_list; + end = p + list_size; + 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(keyring, 1), + "asymmetric", + NULL, + p, + plen, + ((KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW | KEY_USR_READ), + KEY_ALLOC_NOT_IN_QUOTA | + KEY_ALLOC_BUILT_IN | + KEY_ALLOC_BYPASS_RESTRICTION); + 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; +} diff --git a/certs/common.h b/certs/common.h new file mode 100644 index 000000000000..abdb5795936b --- /dev/null +++ b/certs/common.h @@ -0,0 +1,9 @@ +/* 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 diff --git a/certs/system_keyring.c b/certs/system_keyring.c index 798291177186..a44a8915c94c 100644 --- a/certs/system_keyring.c +++ b/certs/system_keyring.c @@ -15,6 +15,7 @@ #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 @@ -136,54 +137,10 @@ device_initcall(system_trusted_keyring_init); */ 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"); - p = system_certificate_list; - end = p + system_certificate_list_size; - 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(builtin_trusted_keys, 1), - "asymmetric", - NULL, - p, - plen, - ((KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ), - KEY_ALLOC_NOT_IN_QUOTA | - KEY_ALLOC_BUILT_IN | - KEY_ALLOC_BYPASS_RESTRICTION); - 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; + return load_certificate_list(system_certificate_list, system_certificate_list_size, + builtin_trusted_keys); } late_initcall(load_system_certificate_list); @@ -241,6 +198,12 @@ int verify_pkcs7_message_sig(const void *data, size_t len, pr_devel("PKCS#7 platform keyring is not available\n"); goto error; } + + ret = is_key_on_revocation_list(pkcs7); + if (ret != -ENOKEY) { + pr_devel("PKCS#7 platform key is on revocation list\n"); + goto error; + } } ret = pkcs7_validate_trust(pkcs7, trusted_keys); if (ret < 0) { |