From patchwork Wed Dec 9 19:42:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tushar Sugandhi X-Patchwork-Id: 11964965 X-Patchwork-Delegate: snitzer@redhat.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5243AC433FE for ; Thu, 10 Dec 2020 14:46:02 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A567A22D74 for ; Thu, 10 Dec 2020 14:46:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A567A22D74 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: mail.kernel.org; spf=tempfail smtp.mailfrom=dm-devel-bounces@redhat.com Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-421-EJOS4K77MCa5UiD71RkBJg-1; Thu, 10 Dec 2020 09:45:58 -0500 X-MC-Unique: EJOS4K77MCa5UiD71RkBJg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5BD8CC292; Thu, 10 Dec 2020 14:45:53 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3EC7B60BF1; Thu, 10 Dec 2020 14:45:53 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 15C4E5002C; Thu, 10 Dec 2020 14:45:53 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 0B9JgVCW017674 for ; Wed, 9 Dec 2020 14:42:31 -0500 Received: by smtp.corp.redhat.com (Postfix) id 6E3E92166B36; Wed, 9 Dec 2020 19:42:31 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast01.extmail.prod.ext.rdu2.redhat.com [10.11.55.17]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 65B652166B31 for ; Wed, 9 Dec 2020 19:42:28 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-1.mimecast.com [207.211.31.81]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id AB31785828C for ; Wed, 9 Dec 2020 19:42:28 +0000 (UTC) Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by relay.mimecast.com with ESMTP id us-mta-191-1oEKQeRYMHimROXaTB9xmQ-1; Wed, 09 Dec 2020 14:42:26 -0500 X-MC-Unique: 1oEKQeRYMHimROXaTB9xmQ-1 Received: from tusharsu-Ubuntu.lan (c-71-197-163-6.hsd1.wa.comcast.net [71.197.163.6]) by linux.microsoft.com (Postfix) with ESMTPSA id A6EB720B7189; Wed, 9 Dec 2020 11:42:24 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com A6EB720B7189 From: Tushar Sugandhi To: zohar@linux.ibm.com, stephen.smalley.work@gmail.com, casey@schaufler-ca.com, agk@redhat.com, snitzer@redhat.com, gmazyland@gmail.com, paul@paul-moore.com Date: Wed, 9 Dec 2020 11:42:08 -0800 Message-Id: <20201209194212.5131-5-tusharsu@linux.microsoft.com> In-Reply-To: <20201209194212.5131-1-tusharsu@linux.microsoft.com> References: <20201209194212.5131-1-tusharsu@linux.microsoft.com> X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-loop: dm-devel@redhat.com X-Mailman-Approved-At: Thu, 10 Dec 2020 09:44:21 -0500 Cc: sashal@kernel.org, dm-devel@redhat.com, selinux@vger.kernel.org, jmorris@namei.org, linux-kernel@vger.kernel.org, nramas@linux.microsoft.com, linux-security-module@vger.kernel.org, tyhicks@linux.microsoft.com, linux-integrity@vger.kernel.org Subject: [dm-devel] [PATCH v7 4/8] IMA: add policy rule to measure critical data X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com A new IMA policy rule is needed for the IMA hook ima_measure_critical_data() and the corresponding func CRITICAL_DATA for measuring the input buffer. The policy rule should ensure the buffer would get measured only when the policy rule allows the action. The policy rule should also support the necessary constraints (flags etc.) for integrity critical buffer data measurements. Add a policy rule to define the constraints for restricting integrity critical data measurements. Signed-off-by: Tushar Sugandhi --- security/integrity/ima/ima_policy.c | 35 +++++++++++++++++++++++++---- 1 file changed, 31 insertions(+), 4 deletions(-) diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 2a0c0603626e..9a8ee80a3128 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -34,6 +34,7 @@ #define IMA_PCR 0x0100 #define IMA_FSNAME 0x0200 #define IMA_KEYRINGS 0x0400 +#define IMA_DATA_SOURCE 0x0800 #define UNKNOWN 0 #define MEASURE 0x0001 /* same as IMA_MEASURE */ @@ -85,6 +86,7 @@ struct ima_rule_entry { } lsm[MAX_LSM_RULES]; char *fsname; struct ima_rule_opt_list *keyrings; /* Measure keys added to these keyrings */ + struct ima_rule_opt_list *data_source; /* Measure data from this source */ struct ima_template_desc *template; }; @@ -479,6 +481,12 @@ static bool ima_match_rule_data(struct ima_rule_entry *rule, else opt_list = rule->keyrings; break; + case CRITICAL_DATA: + if (!rule->data_source) + return true; + else + opt_list = rule->data_source; + break; default: break; } @@ -518,13 +526,19 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode, { int i; - if (func == KEY_CHECK) { - return (rule->flags & IMA_FUNC) && (rule->func == func) && - ima_match_rule_data(rule, func_data, cred); - } if ((rule->flags & IMA_FUNC) && (rule->func != func && func != POST_SETATTR)) return false; + + switch (func) { + case KEY_CHECK: + case CRITICAL_DATA: + return ((rule->func == func) && + ima_match_rule_data(rule, func_data, cred)); + default: + break; + } + if ((rule->flags & IMA_MASK) && (rule->mask != mask && func != POST_SETATTR)) return false; @@ -1119,6 +1133,19 @@ static bool ima_validate_rule(struct ima_rule_entry *entry) if (ima_rule_contains_lsm_cond(entry)) return false; + break; + case CRITICAL_DATA: + if (entry->action & ~(MEASURE | DONT_MEASURE)) + return false; + + if (!(entry->flags & IMA_DATA_SOURCE) || + (entry->flags & ~(IMA_FUNC | IMA_UID | IMA_PCR | + IMA_DATA_SOURCE))) + return false; + + if (ima_rule_contains_lsm_cond(entry)) + return false; + break; default: return false;