From: "Luis R. Rodriguez" <[email protected]> This generalizes the module signing code as helpers, we do this as we'll later re-use this same code for firmware and other system data signing.
Cc: Rusty Russell <[email protected]> Cc: David Howells <[email protected]> Cc: Ming Lei <[email protected]> Cc: Seth Forshee <[email protected]> Cc: Kyle McMartin <[email protected]> Signed-off-by: Luis R. Rodriguez <[email protected]> --- init/Kconfig | 22 ++++--- kernel/Makefile | 2 +- kernel/module.c | 4 +- kernel/{module-internal.h => sysdata-internal.h} | 4 +- kernel/{module_signing.c => sysdata_signing.c} | 76 ++++++++++++------------ kernel/system_keyring.c | 2 +- 6 files changed, 57 insertions(+), 53 deletions(-) rename kernel/{module-internal.h => sysdata-internal.h} (79%) rename kernel/{module_signing.c => sysdata_signing.c} (76%) diff --git a/init/Kconfig b/init/Kconfig index f5dbc6d..862d5ad7 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1769,6 +1769,18 @@ config BASE_SMALL default 0 if BASE_FULL default 1 if !BASE_FULL +config SYSDATA_SIG + def_bool y + select SYSTEM_TRUSTED_KEYRING + select KEYS + select CRYPTO + select ASYMMETRIC_KEY_TYPE + select ASYMMETRIC_PUBLIC_KEY_SUBTYPE + select PUBLIC_KEY_ALGO_RSA + select ASN1 + select OID_REGISTRY + select X509_CERTIFICATE_PARSER + menuconfig MODULES bool "Enable loadable module support" option modules @@ -1842,15 +1854,7 @@ 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 - select ASYMMETRIC_PUBLIC_KEY_SUBTYPE - select PUBLIC_KEY_ALGO_RSA - select ASN1 - select OID_REGISTRY - select X509_CERTIFICATE_PARSER + select SYSDATA_SIG help Check modules for valid signatures upon load: the signature is simply appended to the module. For more information see diff --git a/kernel/Makefile b/kernel/Makefile index 1408b33..e24c9d6 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -45,7 +45,7 @@ endif 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 +obj-$(CONFIG_SYSDATA_SIG) += sysdata_signing.o obj-$(CONFIG_KALLSYMS) += kallsyms.o obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o obj-$(CONFIG_KEXEC) += kexec.o diff --git a/kernel/module.c b/kernel/module.c index 23b2b65..eb61c10 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -60,7 +60,7 @@ #include <linux/pfn.h> #include <linux/bsearch.h> #include <uapi/linux/module.h> -#include "module-internal.h" +#include "sysdata-internal.h" #define CREATE_TRACE_POINTS #include <trace/events/module.h> @@ -2404,7 +2404,7 @@ static int module_sig_check(struct load_info *info) memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) { /* We truncate the module to discard the signature */ info->len -= markerlen; - err = mod_verify_sig(mod, &info->len); + err = sysdata_verify_sig(mod, &info->len); } if (!err) { diff --git a/kernel/module-internal.h b/kernel/sysdata-internal.h similarity index 79% rename from kernel/module-internal.h rename to kernel/sysdata-internal.h index 915e123..0aa573e 100644 --- a/kernel/module-internal.h +++ b/kernel/sysdata-internal.h @@ -1,4 +1,4 @@ -/* Module internals +/* System Data internals * * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) @@ -9,4 +9,4 @@ * 2 of the Licence, or (at your option) any later version. */ -extern int mod_verify_sig(const void *mod, unsigned long *_modlen); +extern int sysdata_verify_sig(const void *data, unsigned long *_len); diff --git a/kernel/module_signing.c b/kernel/sysdata_signing.c similarity index 76% rename from kernel/module_signing.c rename to kernel/sysdata_signing.c index be5b8fa..8ba09aa 100644 --- a/kernel/module_signing.c +++ b/kernel/sysdata_signing.c @@ -1,4 +1,4 @@ -/* Module signature checker +/* System Data signature checker * * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. * Written by David Howells ([email protected]) @@ -15,10 +15,10 @@ #include <crypto/hash.h> #include <keys/asymmetric-type.h> #include <keys/system_keyring.h> -#include "module-internal.h" +#include "sysdata-internal.h" /* - * Module signature information block. + * System Data signature information block. * * The constituents of the signature section are, in order: * @@ -27,7 +27,7 @@ * - Signature data * - Information block */ -struct module_signature { +struct sysdata_signature { u8 algo; /* Public-key crypto algorithm [enum pkey_algo] */ u8 hash; /* Digest algorithm [enum hash_algo] */ u8 id_type; /* Key identifier type [enum pkey_id_type] */ @@ -38,11 +38,11 @@ struct module_signature { }; /* - * Digest the module contents. + * Digest the system data contents. */ -static struct public_key_signature *mod_make_digest(enum hash_algo hash, - const void *mod, - unsigned long modlen) +static struct public_key_signature *data_make_digest(enum hash_algo hash, + const void *data, + unsigned long len) { struct public_key_signature *pks; struct crypto_shash *tfm; @@ -51,7 +51,7 @@ static struct public_key_signature *mod_make_digest(enum hash_algo hash, int ret; pr_devel("==>%s()\n", __func__); - + /* Allocate the hashing algorithm we're going to need and find out how * big the hash operational data will be. */ @@ -82,7 +82,7 @@ static struct public_key_signature *mod_make_digest(enum hash_algo hash, if (ret < 0) goto error; - ret = crypto_shash_finup(desc, mod, modlen, pks->digest); + ret = crypto_shash_finup(desc, data, len, pks->digest); if (ret < 0) goto error; @@ -105,8 +105,8 @@ error_no_pks: * * RSA signatures only have one MPI, so currently we only read one. */ -static int mod_extract_mpi_array(struct public_key_signature *pks, - const void *data, size_t len) +static int data_extract_mpi_array(struct public_key_signature *pks, + const void *data, size_t len) { size_t nbytes; MPI mpi; @@ -161,7 +161,7 @@ static struct key *request_asymmetric_key(const char *signer, size_t signer_len, 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", + pr_warn("Request for unknown system data key '%s' err %ld\n", id, PTR_ERR(key)); kfree(id); @@ -182,58 +182,58 @@ static struct key *request_asymmetric_key(const char *signer, size_t signer_len, } /* - * Verify the signature on a module. + * Verify the signature on system data. */ -int mod_verify_sig(const void *mod, unsigned long *_modlen) +int sysdata_verify_sig(const void *data, unsigned long *_len) { struct public_key_signature *pks; - struct module_signature ms; + struct sysdata_signature ds; struct key *key; const void *sig; - size_t modlen = *_modlen, sig_len; + size_t len = *_len, sig_len; int ret; - pr_devel("==>%s(,%zu)\n", __func__, modlen); + pr_devel("==>%s(,%zu)\n", __func__, len); - if (modlen <= sizeof(ms)) + if (len <= sizeof(ds)) return -EBADMSG; - memcpy(&ms, mod + (modlen - sizeof(ms)), sizeof(ms)); - modlen -= sizeof(ms); + memcpy(&ds, data + (len - sizeof(ds)), sizeof(ds)); + len -= sizeof(ds); - sig_len = be32_to_cpu(ms.sig_len); - if (sig_len >= modlen) + sig_len = be32_to_cpu(ds.sig_len); + if (sig_len >= len) return -EBADMSG; - modlen -= sig_len; - if ((size_t)ms.signer_len + ms.key_id_len >= modlen) + len -= sig_len; + if ((size_t)ds.signer_len + ds.key_id_len >= len) return -EBADMSG; - modlen -= (size_t)ms.signer_len + ms.key_id_len; + len -= (size_t)ds.signer_len + ds.key_id_len; - *_modlen = modlen; - sig = mod + modlen; + *_len = len; + sig = data + len; /* For the moment, only support RSA and X.509 identifiers */ - if (ms.algo != PKEY_ALGO_RSA || - ms.id_type != PKEY_ID_X509) + if (ds.algo != PKEY_ALGO_RSA || + ds.id_type != PKEY_ID_X509) return -ENOPKG; - if (ms.hash >= PKEY_HASH__LAST || - !hash_algo_name[ms.hash]) + if (ds.hash >= PKEY_HASH__LAST || + !hash_algo_name[ds.hash]) return -ENOPKG; - key = request_asymmetric_key(sig, ms.signer_len, - sig + ms.signer_len, ms.key_id_len); + key = request_asymmetric_key(sig, ds.signer_len, + sig + ds.signer_len, ds.key_id_len); if (IS_ERR(key)) return PTR_ERR(key); - pks = mod_make_digest(ms.hash, mod, modlen); + pks = data_make_digest(ds.hash, data, len); if (IS_ERR(pks)) { ret = PTR_ERR(pks); goto error_put_key; } - ret = mod_extract_mpi_array(pks, sig + ms.signer_len + ms.key_id_len, - sig_len); + ret = data_extract_mpi_array(pks, sig + ds.signer_len + ds.key_id_len, + sig_len); if (ret < 0) goto error_free_pks; @@ -246,5 +246,5 @@ error_free_pks: error_put_key: key_put(key); pr_devel("<==%s() = %d\n", __func__, ret); - return ret; + return ret; } diff --git a/kernel/system_keyring.c b/kernel/system_keyring.c index 875f64e..1eb0c86 100644 --- a/kernel/system_keyring.c +++ b/kernel/system_keyring.c @@ -16,7 +16,7 @@ #include <linux/err.h> #include <keys/asymmetric-type.h> #include <keys/system_keyring.h> -#include "module-internal.h" +#include "sysdata-internal.h" struct key *system_trusted_keyring; EXPORT_SYMBOL_GPL(system_trusted_keyring); -- 2.3.2.209.gd67f9d5.dirty -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
