From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pa0-f54.google.com ([209.85.220.54]:33453 "EHLO mail-pa0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754761AbbEMSab (ORCPT ); Wed, 13 May 2015 14:30:31 -0400 From: "Luis R. Rodriguez" To: ming.lei@canonical.com, rusty@rustcorp.com.au Cc: torvalds@linux-foundation.org, dhowells@redhat.com, seth.forshee@canonical.com, linux-kernel@vger.kernel.org, pebolle@tiscali.nl, linux-wireless@vger.kernel.org, gregkh@linuxfoundation.org, jlee@suse.com, tiwai@suse.de, casey@schaufler-ca.com, keescook@chromium.org, mjg59@srcf.ucam.org, akpm@linux-foundation.org, "Luis R. Rodriguez" , Kyle McMartin Subject: [RFC v2 2/6] kernel: generalize module signing as system data signing Date: Wed, 13 May 2015 11:23:52 -0700 Message-Id: <1431541436-17007-3-git-send-email-mcgrof@do-not-panic.com> (sfid-20150513_203043_867169_6E43B790) In-Reply-To: <1431541436-17007-1-git-send-email-mcgrof@do-not-panic.com> References: <1431541436-17007-1-git-send-email-mcgrof@do-not-panic.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: From: "Luis R. Rodriguez" 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. Acked-by: Rusty Russell (module parts) Cc: Rusty Russell Cc: David Howells Cc: Ming Lei Cc: Seth Forshee Cc: Kyle McMartin Signed-off-by: Luis R. Rodriguez --- init/Kconfig | 24 ++++++---- kernel/Makefile | 2 +- kernel/module.c | 4 +- kernel/{module-internal.h => sysdata-internal.h} | 4 +- kernel/{module_signing.c => sysdata_signing.c} | 58 ++++++++++++------------ kernel/system_keyring.c | 2 +- 6 files changed, 49 insertions(+), 45 deletions(-) rename kernel/{module-internal.h => sysdata-internal.h} (79%) rename kernel/{module_signing.c => sysdata_signing.c} (64%) diff --git a/init/Kconfig b/init/Kconfig index fb98cba..a75c587 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1793,6 +1793,19 @@ config BASE_SMALL default 0 if BASE_FULL default 1 if !BASE_FULL +config SYSDATA_SIG + def_bool n + 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 PKCS7_MESSAGE_PARSER + menuconfig MODULES bool "Enable loadable module support" option modules @@ -1866,16 +1879,7 @@ 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 PKCS7_MESSAGE_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 60c302c..ed6a32b 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -47,7 +47,7 @@ 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 9e51b37..6a3f629 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -60,7 +60,7 @@ #include #include #include -#include "module-internal.h" +#include "sysdata-internal.h" #define CREATE_TRACE_POINTS #include @@ -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 (dhowells@redhat.com) @@ -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 64% rename from kernel/module_signing.c rename to kernel/sysdata_signing.c index 8eb20cc..adc44d4 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 (dhowells@redhat.com) @@ -14,10 +14,10 @@ #include #include #include -#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: * @@ -26,7 +26,7 @@ * - Signature data * - Information block */ -struct module_signature { +struct sysdata_signature { u8 algo; /* Public-key crypto algorithm [0] */ u8 hash; /* Digest algorithm [0] */ u8 id_type; /* Key identifier type [PKEY_ID_PKCS7] */ @@ -37,10 +37,10 @@ struct module_signature { }; /* - * Verify a PKCS#7-based signature on a module. + * Verify a PKCS#7-based signature on system data. */ -static int mod_verify_pkcs7(const void *mod, unsigned long modlen, - const void *raw_pkcs7, size_t pkcs7_len) +static int data_verify_pkcs7(const void *data, unsigned long len, + const void *raw_pkcs7, size_t pkcs7_len) { struct pkcs7_message *pkcs7; bool trusted; @@ -51,7 +51,7 @@ static int mod_verify_pkcs7(const void *mod, unsigned long modlen, return PTR_ERR(pkcs7); /* The data should be detached - so we need to supply it. */ - if (pkcs7_supply_detached_data(pkcs7, mod, modlen) < 0) { + if (pkcs7_supply_detached_data(pkcs7, data, len) < 0) { pr_err("PKCS#7 signature with non-detached data\n"); ret = -EBADMSG; goto error; @@ -77,42 +77,42 @@ error: } /* - * 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 module_signature ms; - size_t modlen = *_modlen, sig_len; + struct sysdata_signature ds; + size_t len = *_len, sig_len; - 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; - *_modlen = modlen; + len -= sig_len; + *_len = len; - if (ms.id_type != PKEY_ID_PKCS7) { + if (ds.id_type != PKEY_ID_PKCS7) { pr_err("Module is not signed with expected PKCS#7 message\n"); return -ENOPKG; } - if (ms.algo != 0 || - ms.hash != 0 || - ms.signer_len != 0 || - ms.key_id_len != 0 || - ms.__pad[0] != 0 || - ms.__pad[1] != 0 || - ms.__pad[2] != 0) { + if (ds.algo != 0 || + ds.hash != 0 || + ds.signer_len != 0 || + ds.key_id_len != 0 || + ds.__pad[0] != 0 || + ds.__pad[1] != 0 || + ds.__pad[2] != 0) { pr_err("PKCS#7 signature info has unexpected non-zero params\n"); return -EBADMSG; } - return mod_verify_pkcs7(mod, modlen, mod + modlen, sig_len); + return data_verify_pkcs7(data, len, data + len, sig_len); } 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 #include #include -#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