From patchwork Wed Nov 13 18:46:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lakshmi Ramasubramanian X-Patchwork-Id: 11242663 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1D1E2138C for ; Wed, 13 Nov 2019 18:47:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E2391206F3 for ; Wed, 13 Nov 2019 18:47:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="Y84pILzO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728520AbfKMSrE (ORCPT ); Wed, 13 Nov 2019 13:47:04 -0500 Received: from linux.microsoft.com ([13.77.154.182]:43334 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727122AbfKMSrE (ORCPT ); Wed, 13 Nov 2019 13:47:04 -0500 Received: from nramas-ThinkStation-P520.corp.microsoft.com (unknown [131.107.174.108]) by linux.microsoft.com (Postfix) with ESMTPSA id C6C5A20B4903; Wed, 13 Nov 2019 10:47:02 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com C6C5A20B4903 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1573670822; bh=WvcJyWsHuGMEIucDgLKSJndbtm2SR+vqMHm92p3VGFk=; h=From:To:Subject:Date:In-Reply-To:References:From; b=Y84pILzOwUa8ip7ekcFjXl5s6BjxGKnezIZay3DdX9WK1TfFZI45UnRks9OAFAoA6 L3TfGxF9EKV6/VnZCdpcXdQfIe4VDBuQANefDm7zrvYKRSxa5A3Iyr2xW5k0sJzYO6 iiX7RRt4lvxjrOSqA0plktyG7sTcAwUu1Lpnxw/0= From: Lakshmi Ramasubramanian To: zohar@linux.ibm.com, dhowells@redhat.com, matthewgarrett@google.com, sashal@kernel.org, jamorris@linux.microsoft.com, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, keyrings@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v6 1/3] IMA: Add KEY_CHECK func to measure keys Date: Wed, 13 Nov 2019 10:46:56 -0800 Message-Id: <20191113184658.2862-2-nramas@linux.microsoft.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191113184658.2862-1-nramas@linux.microsoft.com> References: <20191113184658.2862-1-nramas@linux.microsoft.com> Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Measure keys loaded onto any keyring. This patch defines a new IMA policy func namely KEY_CHECK to measure keys. Updated ima_match_rules() to check for KEY_CHECK and ima_parse_rule() to handle KEY_CHECK. Signed-off-by: Lakshmi Ramasubramanian --- Documentation/ABI/testing/ima_policy | 6 +++++- security/integrity/ima/ima.h | 1 + security/integrity/ima/ima_main.c | 7 +++++++ security/integrity/ima/ima_policy.c | 4 +++- 4 files changed, 16 insertions(+), 2 deletions(-) diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy index 29aaedf33246..066d32797500 100644 --- a/Documentation/ABI/testing/ima_policy +++ b/Documentation/ABI/testing/ima_policy @@ -29,7 +29,7 @@ Description: base: func:= [BPRM_CHECK][MMAP_CHECK][CREDS_CHECK][FILE_CHECK][MODULE_CHECK] [FIRMWARE_CHECK] [KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK] - [KEXEC_CMDLINE] + [KEXEC_CMDLINE] [KEY_CHECK] mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND] [[^]MAY_EXEC] fsmagic:= hex value @@ -113,3 +113,7 @@ Description: Example of appraise rule allowing modsig appended signatures: appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig + + Example of measure rule using KEY_CHECK to measure all keys: + + measure func=KEY_CHECK diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index df4ca482fb53..fe6c698617bd 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -193,6 +193,7 @@ static inline unsigned long ima_hash_key(u8 *digest) hook(KEXEC_INITRAMFS_CHECK) \ hook(POLICY_CHECK) \ hook(KEXEC_CMDLINE) \ + hook(KEY_CHECK) \ hook(MAX_CHECK) #define __ima_hook_enumify(ENUM) ENUM, diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index d7e987baf127..12684e8d7124 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -655,6 +655,13 @@ void process_buffer_measurement(const void *buf, int size, int action = 0; u32 secid; + /* + * If IMA is not yet initialized or IMA policy is empty + * then there is no need to measure. + */ + if (!ima_policy_flag) + return; + /* * Both LSM hooks and auxilary based buffer measurements are * based on policy. To avoid code duplication, differentiate diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index f19a895ad7cd..1525a28fd705 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -373,7 +373,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode, { int i; - if (func == KEXEC_CMDLINE) { + if ((func == KEXEC_CMDLINE) || (func == KEY_CHECK)) { if ((rule->flags & IMA_FUNC) && (rule->func == func)) return true; return false; @@ -997,6 +997,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) entry->func = POLICY_CHECK; else if (strcmp(args[0].from, "KEXEC_CMDLINE") == 0) entry->func = KEXEC_CMDLINE; + else if (strcmp(args[0].from, "KEY_CHECK") == 0) + entry->func = KEY_CHECK; else result = -EINVAL; if (!result)