From patchwork Thu Aug 18 15:29:28 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12947341 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 1E748C38142 for ; Thu, 18 Aug 2022 15:51:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343989AbiHRPvD (ORCPT ); Thu, 18 Aug 2022 11:51:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46666 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344442AbiHRPue (ORCPT ); Thu, 18 Aug 2022 11:50:34 -0400 Received: from frasgout12.his.huawei.com (frasgout12.his.huawei.com [14.137.139.154]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 242E55C373; Thu, 18 Aug 2022 08:50:30 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout12.his.huawei.com (SkyGuard) with ESMTP id 4M7pjX2WXTz9v7Yk; Thu, 18 Aug 2022 23:30:08 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP2 (Coremail) with SMTP id GxC2BwB3MhqAW_5ilLIyAA--.42520S6; Thu, 18 Aug 2022 16:33:15 +0100 (CET) From: roberto.sassu@huaweicloud.com To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, mykolal@fb.com, corbet@lwn.net, dhowells@redhat.com, jarkko@kernel.org, rostedt@goodmis.org, mingo@redhat.com, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, shuah@kernel.org Cc: bpf@vger.kernel.org, linux-doc@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, deso@posteo.net, Roberto Sassu Subject: [PATCH v12 09/10] selftests/bpf: Add additional tests for bpf_lookup_*_key() Date: Thu, 18 Aug 2022 17:29:28 +0200 Message-Id: <20220818152929.402605-10-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220818152929.402605-1-roberto.sassu@huaweicloud.com> References: <20220818152929.402605-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: GxC2BwB3MhqAW_5ilLIyAA--.42520S6 X-Coremail-Antispam: 1UD129KBjvJXoW3XF13WF17try8WFyrXFykGrg_yoW7AryDpF yUGa4Fyry09r1Utan3AF17AF1rKF4Uu3W2ywnrWr13uw1kZFy8Gw4xKa1agasxWrZ8Zwn3 ua1Yga1jkr4UZa7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPab4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6r1j6r18M7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWUCVW8JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv6xkF7I0E 14v26r4UJVWxJr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrV C2j2WlYx0E2Ix0cI8IcVAFwI0_JrI_JrylYx0Ex4A2jsIE14v26r4j6F4UMcvjeVCFs4IE 7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwAKzVCY07 xG64k0F24l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG 67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r4a6rW5MI IYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_JFI_Gr1lIxAIcVC0I7IYx2IY6xkF7I0E 14v26r4UJVWxJr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r 4j6F4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr1j6F4UJbIYCTnIWIevJa73UjIFyTuYvjxU wXo7DUUUU X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgAIBF1jj34XLQAAs7 X-CFilter-Loop: Reflected Precedence: bulk List-ID: From: Roberto Sassu Add a test to ensure that bpf_lookup_user_key() creates a referenced special keyring when the KEY_LOOKUP_CREATE flag is passed to this function. Ensure that the kfunc rejects invalid flags. Ensure that a keyring can be obtained from bpf_lookup_system_key() when one of the pre-determined keyring IDs is provided. Signed-off-by: Roberto Sassu --- .../selftests/bpf/prog_tests/lookup_key.c | 112 ++++++++++++++++++ .../selftests/bpf/progs/test_lookup_key.c | 46 +++++++ 2 files changed, 158 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/lookup_key.c create mode 100644 tools/testing/selftests/bpf/progs/test_lookup_key.c diff --git a/tools/testing/selftests/bpf/prog_tests/lookup_key.c b/tools/testing/selftests/bpf/prog_tests/lookup_key.c new file mode 100644 index 000000000000..2e0cde729dc7 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/lookup_key.c @@ -0,0 +1,112 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Copyright (C) 2022 Huawei Technologies Duesseldorf GmbH + * + * Author: Roberto Sassu + */ + +#include +#include + +#include "test_lookup_key.skel.h" + +#define KEY_LOOKUP_CREATE 0x01 +#define KEY_LOOKUP_PARTIAL 0x02 + +static bool kfunc_not_supported; + +static int libbpf_print_cb(enum libbpf_print_level level, const char *fmt, + va_list args) +{ + char *func; + + if (strcmp(fmt, "libbpf: extern (func ksym) '%s': not found in kernel or module BTFs\n")) + return 0; + + func = va_arg(args, char *); + + if (strcmp(func, "bpf_lookup_user_key") && strcmp(func, "bpf_key_put") && + strcmp(func, "bpf_lookup_system_key")) + return 0; + + kfunc_not_supported = true; + return 0; +} + +void test_lookup_key(void) +{ + libbpf_print_fn_t old_print_cb; + struct test_lookup_key *skel; + u32 next_id; + int ret; + + skel = test_lookup_key__open(); + if (!ASSERT_OK_PTR(skel, "test_lookup_key__open")) + return; + + old_print_cb = libbpf_set_print(libbpf_print_cb); + ret = test_lookup_key__load(skel); + libbpf_set_print(old_print_cb); + + if (ret < 0 && kfunc_not_supported) { + printf("%s:SKIP:bpf_lookup_*_key(), bpf_key_put() kfuncs not supported\n", + __func__); + test__skip(); + goto close_prog; + } + + if (!ASSERT_OK(ret, "test_lookup_key__load")) + goto close_prog; + + ret = test_lookup_key__attach(skel); + if (!ASSERT_OK(ret, "test_lookup_key__attach")) + goto close_prog; + + skel->bss->monitored_pid = getpid(); + skel->bss->key_serial = KEY_SPEC_THREAD_KEYRING; + + /* The thread-specific keyring does not exist, this test fails. */ + skel->bss->flags = 0; + + ret = bpf_prog_get_next_id(0, &next_id); + if (!ASSERT_LT(ret, 0, "bpf_prog_get_next_id")) + goto close_prog; + + /* Force creation of the thread-specific keyring, this test succeeds. */ + skel->bss->flags = KEY_LOOKUP_CREATE; + + ret = bpf_prog_get_next_id(0, &next_id); + if (!ASSERT_OK(ret, "bpf_prog_get_next_id")) + goto close_prog; + + /* Pass both lookup flags for parameter validation. */ + skel->bss->flags = KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL; + + ret = bpf_prog_get_next_id(0, &next_id); + if (!ASSERT_OK(ret, "bpf_prog_get_next_id")) + goto close_prog; + + /* Pass invalid flags. */ + skel->bss->flags = UINT64_MAX; + + ret = bpf_prog_get_next_id(0, &next_id); + if (!ASSERT_LT(ret, 0, "bpf_prog_get_next_id")) + goto close_prog; + + skel->bss->key_serial = 0; + skel->bss->key_id = 1; + + ret = bpf_prog_get_next_id(0, &next_id); + if (!ASSERT_OK(ret, "bpf_prog_get_next_id")) + goto close_prog; + + skel->bss->key_id = UINT32_MAX; + + ret = bpf_prog_get_next_id(0, &next_id); + ASSERT_LT(ret, 0, "bpf_prog_get_next_id"); + +close_prog: + skel->bss->monitored_pid = 0; + test_lookup_key__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_lookup_key.c b/tools/testing/selftests/bpf/progs/test_lookup_key.c new file mode 100644 index 000000000000..c73776990ae3 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_lookup_key.c @@ -0,0 +1,46 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Copyright (C) 2022 Huawei Technologies Duesseldorf GmbH + * + * Author: Roberto Sassu + */ + +#include "vmlinux.h" +#include +#include +#include + +char _license[] SEC("license") = "GPL"; + +__u32 monitored_pid; +__u32 key_serial; +__u32 key_id; +__u64 flags; + +extern struct bpf_key *bpf_lookup_user_key(__u32 serial, __u64 flags) __ksym; +extern struct bpf_key *bpf_lookup_system_key(__u64 id) __ksym; +extern void bpf_key_put(struct bpf_key *key) __ksym; + +SEC("lsm.s/bpf") +int BPF_PROG(bpf, int cmd, union bpf_attr *attr, unsigned int size) +{ + struct bpf_key *bkey; + __u32 pid; + + pid = bpf_get_current_pid_tgid() >> 32; + if (pid != monitored_pid) + return 0; + + if (key_serial) + bkey = bpf_lookup_user_key(key_serial, flags); + else + bkey = bpf_lookup_system_key(key_id); + + if (!bkey) + return -ENOENT; + + bpf_key_put(bkey); + + return 0; +}