From patchwork Wed Mar 2 11:14:00 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12765802 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8FC1EC4332F for ; Wed, 2 Mar 2022 11:18:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241466AbiCBLT2 (ORCPT ); Wed, 2 Mar 2022 06:19:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51724 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241726AbiCBLSa (ORCPT ); Wed, 2 Mar 2022 06:18:30 -0500 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 24FCAC4B62; Wed, 2 Mar 2022 03:16:04 -0800 (PST) Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.206]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4K7s2n1t9Zz67Z6v; Wed, 2 Mar 2022 19:14:41 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Wed, 2 Mar 2022 12:15:48 +0100 From: Roberto Sassu To: , , , , , , , , CC: , , , , , , Roberto Sassu Subject: [PATCH v3 5/9] selftests/bpf: Add test for bpf_ima_file_hash() Date: Wed, 2 Mar 2022 12:14:00 +0100 Message-ID: <20220302111404.193900-6-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220302111404.193900-1-roberto.sassu@huawei.com> References: <20220302111404.193900-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml751-chm.china.huawei.com (10.201.108.201) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: Add new test to ensure that bpf_ima_file_hash() returns the digest of the executed files. Signed-off-by: Roberto Sassu --- .../selftests/bpf/prog_tests/test_ima.c | 43 +++++++++++++++++-- tools/testing/selftests/bpf/progs/ima.c | 10 ++++- 2 files changed, 47 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/test_ima.c b/tools/testing/selftests/bpf/prog_tests/test_ima.c index 97d8a6f84f4a..acc911ba63fd 100644 --- a/tools/testing/selftests/bpf/prog_tests/test_ima.c +++ b/tools/testing/selftests/bpf/prog_tests/test_ima.c @@ -13,6 +13,8 @@ #include "ima.skel.h" +#define MAX_SAMPLES 2 + static int run_measured_process(const char *measured_dir, u32 *monitored_pid) { int child_pid, child_status; @@ -32,14 +34,25 @@ static int run_measured_process(const char *measured_dir, u32 *monitored_pid) return -EINVAL; } -static u64 ima_hash_from_bpf; +static u64 ima_hash_from_bpf[MAX_SAMPLES]; +static int ima_hash_from_bpf_idx; static int process_sample(void *ctx, void *data, size_t len) { - ima_hash_from_bpf = *((u64 *)data); + if (ima_hash_from_bpf_idx >= MAX_SAMPLES) + return -ENOSPC; + + ima_hash_from_bpf[ima_hash_from_bpf_idx++] = *((u64 *)data); return 0; } +static void test_init(struct ima__bss *bss) +{ + ima_hash_from_bpf_idx = 0; + + bss->use_ima_file_hash = false; +} + void test_test_ima(void) { char measured_dir_template[] = "/tmp/ima_measuredXXXXXX"; @@ -72,13 +85,35 @@ void test_test_ima(void) if (CHECK(err, "failed to run command", "%s, errno = %d\n", cmd, errno)) goto close_clean; + /* + * Test #1 + * - Goal: obtain a sample with the bpf_ima_inode_hash() helper + * - Expected result: 1 sample (/bin/true) + */ + test_init(skel->bss); err = run_measured_process(measured_dir, &skel->bss->monitored_pid); - if (CHECK(err, "run_measured_process", "err = %d\n", err)) + if (CHECK(err, "run_measured_process #1", "err = %d\n", err)) goto close_clean; err = ring_buffer__consume(ringbuf); ASSERT_EQ(err, 1, "num_samples_or_err"); - ASSERT_NEQ(ima_hash_from_bpf, 0, "ima_hash"); + ASSERT_NEQ(ima_hash_from_bpf[0], 0, "ima_hash"); + + /* + * Test #2 + * - Goal: obtain samples with the bpf_ima_file_hash() helper + * - Expected result: 2 samples (./ima_setup.sh, /bin/true) + */ + test_init(skel->bss); + skel->bss->use_ima_file_hash = true; + err = run_measured_process(measured_dir, &skel->bss->monitored_pid); + if (CHECK(err, "run_measured_process #2", "err = %d\n", err)) + goto close_clean; + + err = ring_buffer__consume(ringbuf); + ASSERT_EQ(err, 2, "num_samples_or_err"); + ASSERT_NEQ(ima_hash_from_bpf[0], 0, "ima_hash"); + ASSERT_NEQ(ima_hash_from_bpf[1], 0, "ima_hash"); close_clean: snprintf(cmd, sizeof(cmd), "./ima_setup.sh cleanup %s", measured_dir); diff --git a/tools/testing/selftests/bpf/progs/ima.c b/tools/testing/selftests/bpf/progs/ima.c index b5a0de50d1b4..e0b073dcfb5d 100644 --- a/tools/testing/selftests/bpf/progs/ima.c +++ b/tools/testing/selftests/bpf/progs/ima.c @@ -18,6 +18,8 @@ struct { char _license[] SEC("license") = "GPL"; +bool use_ima_file_hash; + static void ima_test_common(struct file *file) { u64 ima_hash = 0; @@ -27,8 +29,12 @@ static void ima_test_common(struct file *file) pid = bpf_get_current_pid_tgid() >> 32; if (pid == monitored_pid) { - ret = bpf_ima_inode_hash(file->f_inode, &ima_hash, - sizeof(ima_hash)); + if (!use_ima_file_hash) + ret = bpf_ima_inode_hash(file->f_inode, &ima_hash, + sizeof(ima_hash)); + else + ret = bpf_ima_file_hash(file, &ima_hash, + sizeof(ima_hash)); if (ret < 0 || ima_hash == 0) return;