From patchwork Wed Jun 7 23:53:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 13271480 X-Patchwork-Delegate: paul@paul-moore.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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EDE67C7EE23 for ; Wed, 7 Jun 2023 23:54:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232646AbjFGXyP convert rfc822-to-8bit (ORCPT ); Wed, 7 Jun 2023 19:54:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53280 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230445AbjFGXyN (ORCPT ); Wed, 7 Jun 2023 19:54:13 -0400 Received: from mx0a-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 30767212E for ; Wed, 7 Jun 2023 16:54:11 -0700 (PDT) Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.17.1.19/8.17.1.19) with ESMTP id 357H1Rxd017034 for ; Wed, 7 Jun 2023 16:54:10 -0700 Received: from maileast.thefacebook.com ([163.114.130.16]) by m0001303.ppops.net (PPS) with ESMTPS id 3r2aabk0kw-9 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Wed, 07 Jun 2023 16:54:10 -0700 Received: from twshared52565.14.frc2.facebook.com (2620:10d:c0a8:1c::11) by mail.thefacebook.com (2620:10d:c0a8:82::c) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Wed, 7 Jun 2023 16:54:04 -0700 Received: by devbig019.vll3.facebook.com (Postfix, from userid 137359) id 986BB32857D3E; Wed, 7 Jun 2023 16:53:59 -0700 (PDT) From: Andrii Nakryiko To: CC: , , , , , , Subject: [PATCH v2 bpf-next 03/18] selftests/bpf: add BPF_TOKEN_CREATE test Date: Wed, 7 Jun 2023 16:53:37 -0700 Message-ID: <20230607235352.1723243-4-andrii@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230607235352.1723243-1-andrii@kernel.org> References: <20230607235352.1723243-1-andrii@kernel.org> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-ORIG-GUID: 41U6S9J3LJC6AK9Fkv-IiNRBB2PT14vc X-Proofpoint-GUID: 41U6S9J3LJC6AK9Fkv-IiNRBB2PT14vc X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.957,Hydra:6.0.573,FMLib:17.11.176.26 definitions=2023-06-07_13,2023-06-07_01,2023-05-22_02 Precedence: bulk List-ID: Add a subtest validating BPF_TOKEN_CREATE command, pinning/getting BPF token in/from BPF FS, and creating derived BPF tokens using token_fd parameter. Signed-off-by: Andrii Nakryiko --- .../testing/selftests/bpf/prog_tests/token.c | 93 +++++++++++++++++++ 1 file changed, 93 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/token.c diff --git a/tools/testing/selftests/bpf/prog_tests/token.c b/tools/testing/selftests/bpf/prog_tests/token.c new file mode 100644 index 000000000000..cba84c480ac5 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/token.c @@ -0,0 +1,93 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ +#include "linux/bpf.h" +#include +#include +#include "cap_helpers.h" + +static int drop_priv_caps(__u64 *old_caps) +{ + return cap_disable_effective((1ULL << CAP_BPF) | + (1ULL << CAP_PERFMON) | + (1ULL << CAP_NET_ADMIN) | + (1ULL << CAP_SYS_ADMIN), old_caps); +} + +static int restore_priv_caps(__u64 old_caps) +{ + return cap_enable_effective(old_caps, NULL); +} + +#define TOKEN_PATH "/sys/fs/bpf/test_token" + +static void subtest_token_create(void) +{ + LIBBPF_OPTS(bpf_token_create_opts, opts); + int token_fd = 0, limited_token_fd = 0, tmp_fd = 0, err; + __u64 old_caps = 0; + + /* check that any current and future cmd can be specified */ + opts.allowed_cmds = ~0ULL; + token_fd = bpf_token_create(&opts); + if (!ASSERT_GT(token_fd, 0, "token_create_future_proof")) + return; + close(token_fd); + + /* create BPF token which allows creating derived BPF tokens */ + opts.allowed_cmds = 1ULL << BPF_TOKEN_CREATE; + token_fd = bpf_token_create(&opts); + if (!ASSERT_GT(token_fd, 0, "token_create")) + return; + + /* validate pinning and getting works as expected */ + err = bpf_obj_pin(token_fd, TOKEN_PATH); + if (!ASSERT_OK(err, "token_pin")) + goto cleanup; + + tmp_fd = bpf_obj_get(TOKEN_PATH); + ASSERT_GT(tmp_fd, 0, "token_get"); + close(tmp_fd); + tmp_fd = 0; + unlink(TOKEN_PATH); + + /* drop privileges to test token_fd passing */ + if (!ASSERT_OK(drop_priv_caps(&old_caps), "drop_caps")) + goto cleanup; + + /* unprivileged BPF_TOKEN_CREATE should fail */ + tmp_fd = bpf_token_create(NULL); + if (!ASSERT_LT(tmp_fd, 0, "token_create_unpriv_fail")) + goto cleanup; + + /* unprivileged BPF_TOKEN_CREATE with associated BPF token succeeds */ + opts.flags = 0; + opts.allowed_cmds = 0; /* ask for BPF token which doesn't allow new tokens */ + opts.token_fd = token_fd; + limited_token_fd = bpf_token_create(&opts); + if (!ASSERT_GT(limited_token_fd, 0, "token_create_limited")) + goto cleanup; + + /* creating yet another token using "limited" BPF token should fail */ + opts.flags = 0; + opts.allowed_cmds = 0; + opts.token_fd = limited_token_fd; + tmp_fd = bpf_token_create(&opts); + if (!ASSERT_LT(tmp_fd, 0, "token_create_from_lim_fail")) + goto cleanup; + +cleanup: + if (tmp_fd) + close(tmp_fd); + if (token_fd) + close(token_fd); + if (limited_token_fd) + close(limited_token_fd); + if (old_caps) + ASSERT_OK(restore_priv_caps(old_caps), "restore_caps"); +} + +void test_token(void) +{ + if (test__start_subtest("token_create")) + subtest_token_create(); +}