From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nayna Jain Subject: [PATCH v6 5/9] powerpc/ima: add measurement rules to ima arch specific policy Date: Fri, 27 Sep 2019 10:25:56 -0400 Message-ID: <1569594360-7141-6-git-send-email-nayna@linux.ibm.com> References: <1569594360-7141-1-git-send-email-nayna@linux.ibm.com> Return-path: In-Reply-To: <1569594360-7141-1-git-send-email-nayna@linux.ibm.com> Sender: linux-kernel-owner@vger.kernel.org To: linuxppc-dev@ozlabs.org, linux-efi@vger.kernel.org, linux-integrity@vger.kernel.org, devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Ard Biesheuvel , Jeremy Kerr , Matthew Garret , Mimi Zohar , Greg Kroah-Hartman , Claudio Carvalho , George Wilson , Elaine Palmer , Eric Ricther , Oliver O'Halloran , Rob Herring , Mark Rutland , Nayna Jain List-Id: devicetree@vger.kernel.org This patch adds the measurement rules to the arch specific policies for the systems with trusted boot. Signed-off-by: Nayna Jain --- arch/powerpc/kernel/ima_arch.c | 44 +++++++++++++++++++++++++++++++--- 1 file changed, 41 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kernel/ima_arch.c b/arch/powerpc/kernel/ima_arch.c index 39401b67f19e..77c61b142042 100644 --- a/arch/powerpc/kernel/ima_arch.c +++ b/arch/powerpc/kernel/ima_arch.c @@ -12,8 +12,18 @@ bool arch_ima_get_secureboot(void) return is_powerpc_os_secureboot_enabled(); } -/* Defines IMA appraise rules for secureboot */ +/* + * The "arch_rules" contains both the securebot and trustedboot rules for adding + * the kexec kernel image and kernel modules file hashes to the IMA measurement + * list and verifying the file signatures against known good values. + * + * The "appraise_type=imasig|modsig" option allows the good signature to be + * stored as an xattr or as an appended signature. The "template=ima-modsig" + * option includes the appended signature in the IMA measurement list. + */ static const char *const arch_rules[] = { + "measure func=KEXEC_KERNEL_CHECK template=ima-modsig", + "measure func=MODULE_CHECK template=ima-modsig", "appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig", #if !IS_ENABLED(CONFIG_MODULE_SIG) "appraise func=MODULE_CHECK appraise_type=imasig|modsig", @@ -22,12 +32,40 @@ static const char *const arch_rules[] = { }; /* - * Returns the relevant IMA arch policies based on the system secureboot state. + * The "measure_rules" are enabled only on "trustedboot" enabled systems. + * These rules add the kexec kernel image and kernel modules file hashes to + * the IMA measurement list. + */ +static const char *const measure_rules[] = { + "measure func=KEXEC_KERNEL_CHECK", + "measure func=MODULE_CHECK", + NULL +}; + +/* + * Returns the relevant IMA arch policies based on the system secureboot + * and trustedboot state. */ const char *const *arch_get_ima_policy(void) { - if (is_powerpc_os_secureboot_enabled()) + const char *const *rules; + int offset = 0; + + for (rules = arch_rules; *rules != NULL; rules++) { + if (strncmp(*rules, "appraise", 8) == 0) + break; + offset++; + } + + if (is_powerpc_os_secureboot_enabled() + && is_powerpc_trustedboot_enabled()) return arch_rules; + if (is_powerpc_os_secureboot_enabled()) + return arch_rules + offset; + + if (is_powerpc_trustedboot_enabled()) + return measure_rules; + return NULL; } -- 2.20.1