BPF Archive on lore.kernel.org
 help / color / Atom feed
From: KP Singh <kpsingh@chromium.org>
To: linux-kernel@vger.kernel.org, bpf@vger.kernel.org,
	linux-security-module@vger.kernel.org
Cc: Andrii Nakryiko <andriin@fb.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Martin KaFai Lau <kafai@fb.com>, Paul Turner <pjt@google.com>,
	Jann Horn <jannh@google.com>,
	Florent Revest <revest@chromium.org>
Subject: [PATCH bpf-next v6 7/7] bpf: Add selftests for local_storage
Date: Thu, 23 Jul 2020 13:50:32 +0200
Message-ID: <20200723115032.460770-8-kpsingh@chromium.org> (raw)
In-Reply-To: <20200723115032.460770-1-kpsingh@chromium.org>

From: KP Singh <kpsingh@google.com>

inode_local_storage:

* Hook to the file_open and inode_unlink LSM hooks.
* Create and unlink a temporary file.
* Store some information in the inode's bpf_local_storage during
  file_open.
* Verify that this information exists when the file is unlinked.

sk_local_storage:

* Hook to the socket_post_create and socket_bind LSM hooks.
* Open and bind a socket and set the sk_storage in the
  socket_post_create hook using the start_server helper.
* Verify if the information is set in the socket_bind hook.

Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: KP Singh <kpsingh@google.com>
---
 .../bpf/prog_tests/test_local_storage.c       |  60 ++++++++
 .../selftests/bpf/progs/local_storage.c       | 136 ++++++++++++++++++
 2 files changed, 196 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/prog_tests/test_local_storage.c
 create mode 100644 tools/testing/selftests/bpf/progs/local_storage.c

diff --git a/tools/testing/selftests/bpf/prog_tests/test_local_storage.c b/tools/testing/selftests/bpf/prog_tests/test_local_storage.c
new file mode 100644
index 000000000000..d4ba89195c43
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/test_local_storage.c
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Copyright (C) 2020 Google LLC.
+ */
+
+#include <test_progs.h>
+#include <linux/limits.h>
+
+#include "local_storage.skel.h"
+#include "network_helpers.h"
+
+int create_and_unlink_file(void)
+{
+	char fname[PATH_MAX] = "/tmp/fileXXXXXX";
+	int fd;
+
+	fd = mkstemp(fname);
+	if (fd < 0)
+		return fd;
+
+	close(fd);
+	unlink(fname);
+	return 0;
+}
+
+void test_test_local_storage(void)
+{
+	struct local_storage *skel = NULL;
+	int err, duration = 0, serv_sk = -1;
+
+	skel = local_storage__open_and_load();
+	if (CHECK(!skel, "skel_load", "lsm skeleton failed\n"))
+		goto close_prog;
+
+	err = local_storage__attach(skel);
+	if (CHECK(err, "attach", "lsm attach failed: %d\n", err))
+		goto close_prog;
+
+	skel->bss->monitored_pid = getpid();
+
+	err = create_and_unlink_file();
+	if (CHECK(err < 0, "exec_cmd", "err %d errno %d\n", err, errno))
+		goto close_prog;
+
+	CHECK(!skel->bss->inode_storage_result, "inode_storage_result",
+	      "inode_local_storage not set");
+
+	serv_sk = start_server(AF_INET6, SOCK_STREAM, NULL, 0, 0);
+	if (CHECK(serv_sk < 0, "start_server", "failed to start server\n"))
+		goto close_prog;
+
+	CHECK(!skel->bss->sk_storage_result, "sk_storage_result",
+	      "sk_local_storage not set");
+
+	close(serv_sk);
+
+close_prog:
+	local_storage__destroy(skel);
+}
diff --git a/tools/testing/selftests/bpf/progs/local_storage.c b/tools/testing/selftests/bpf/progs/local_storage.c
new file mode 100644
index 000000000000..cb608b7b90f0
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/local_storage.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Copyright 2020 Google LLC.
+ */
+
+#include <errno.h>
+#include <linux/bpf.h>
+#include <stdbool.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+#define DUMMY_STORAGE_VALUE 0xdeadbeef
+
+int monitored_pid = 0;
+bool inode_storage_result = false;
+bool sk_storage_result = false;
+
+struct dummy_storage {
+	__u32 value;
+};
+
+struct {
+	__uint(type, BPF_MAP_TYPE_INODE_STORAGE);
+	__uint(map_flags, BPF_F_NO_PREALLOC);
+	__type(key, int);
+	__type(value, struct dummy_storage);
+} inode_storage_map SEC(".maps");
+
+struct {
+	__uint(type, BPF_MAP_TYPE_SK_STORAGE);
+	__uint(map_flags, BPF_F_NO_PREALLOC | BPF_F_CLONE);
+	__type(key, int);
+	__type(value, struct dummy_storage);
+} sk_storage_map SEC(".maps");
+
+/* TODO Use vmlinux.h once BTF pruning for embedded types is fixed.
+ */
+struct sock {} __attribute__((preserve_access_index));
+struct sockaddr {} __attribute__((preserve_access_index));
+struct socket {
+	struct sock *sk;
+} __attribute__((preserve_access_index));
+
+struct inode {} __attribute__((preserve_access_index));
+struct dentry {
+	struct inode *d_inode;
+} __attribute__((preserve_access_index));
+struct file {
+	struct inode *f_inode;
+} __attribute__((preserve_access_index));
+
+
+SEC("lsm/inode_unlink")
+int BPF_PROG(unlink_hook, struct inode *dir, struct dentry *victim)
+{
+	__u32 pid = bpf_get_current_pid_tgid() >> 32;
+	struct dummy_storage *storage;
+
+	if (pid != monitored_pid)
+		return 0;
+
+	storage = bpf_inode_storage_get(&inode_storage_map, victim->d_inode, 0,
+				     BPF_SK_STORAGE_GET_F_CREATE);
+	if (!storage)
+		return 0;
+
+	if (storage->value == DUMMY_STORAGE_VALUE)
+		inode_storage_result = true;
+
+	return 0;
+}
+
+SEC("lsm/socket_bind")
+int BPF_PROG(socket_bind, struct socket *sock, struct sockaddr *address,
+	     int addrlen)
+{
+	__u32 pid = bpf_get_current_pid_tgid() >> 32;
+	struct dummy_storage *storage;
+
+	if (pid != monitored_pid)
+		return 0;
+
+	storage = bpf_sk_storage_get(&sk_storage_map, sock->sk, 0,
+				     BPF_SK_STORAGE_GET_F_CREATE);
+	if (!storage)
+		return 0;
+
+	if (storage->value == DUMMY_STORAGE_VALUE)
+		sk_storage_result = true;
+
+	return 0;
+}
+
+SEC("lsm/socket_post_create")
+int BPF_PROG(socket_post_create, struct socket *sock, int family, int type,
+	     int protocol, int kern)
+{
+	__u32 pid = bpf_get_current_pid_tgid() >> 32;
+	struct dummy_storage *storage;
+
+	if (pid != monitored_pid)
+		return 0;
+
+	storage = bpf_sk_storage_get(&sk_storage_map, sock->sk, 0,
+				     BPF_SK_STORAGE_GET_F_CREATE);
+	if (!storage)
+		return 0;
+
+	storage->value = DUMMY_STORAGE_VALUE;
+
+	return 0;
+}
+
+SEC("lsm/file_open")
+int BPF_PROG(test_int_hook, struct file *file)
+{
+	__u32 pid = bpf_get_current_pid_tgid() >> 32;
+	struct dummy_storage *storage;
+
+	if (pid != monitored_pid)
+		return 0;
+
+	if (!file->f_inode)
+		return 0;
+
+	storage = bpf_inode_storage_get(&inode_storage_map, file->f_inode, 0,
+				     BPF_LOCAL_STORAGE_GET_F_CREATE);
+	if (!storage)
+		return 0;
+
+	storage->value = DUMMY_STORAGE_VALUE;
+	return 0;
+}
-- 
2.28.0.rc0.105.gf9edc3c819-goog


      parent reply index

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-23 11:50 [PATCH bpf-next v6 0/7] Generalizing bpf_local_storage KP Singh
2020-07-23 11:50 ` [PATCH bpf-next v6 1/7] bpf: Renames to prepare for generalizing sk_storage KP Singh
2020-07-24  5:31   ` Martin KaFai Lau
2020-07-24 15:44     ` KP Singh
2020-07-23 11:50 ` [PATCH bpf-next v6 2/7] bpf: Generalize caching for sk_storage KP Singh
2020-07-23 11:50 ` [PATCH bpf-next v6 3/7] bpf: Generalize bpf_sk_storage KP Singh
2020-07-25  1:13   ` Martin KaFai Lau
2020-07-27 20:28     ` KP Singh
2020-07-25  1:30   ` [RFC PATCH bpf-next] bpf: POC on local_storage charge and uncharge map_ops Martin KaFai Lau
2020-07-27 20:26     ` KP Singh
2020-07-27 21:43       ` Martin KaFai Lau
2020-07-23 11:50 ` [PATCH bpf-next v6 4/7] bpf: Split bpf_local_storage to bpf_sk_storage KP Singh
2020-07-23 11:50 ` [PATCH bpf-next v6 5/7] bpf: Implement bpf_local_storage for inodes KP Singh
2020-07-23 11:50 ` [PATCH bpf-next v6 6/7] bpf: Allow local storage to be used from LSM programs KP Singh
2020-07-23 11:50 ` KP Singh [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200723115032.460770-8-kpsingh@chromium.org \
    --to=kpsingh@chromium.org \
    --cc=andriin@fb.com \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=jannh@google.com \
    --cc=kafai@fb.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=pjt@google.com \
    --cc=revest@chromium.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

BPF Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/bpf/0 bpf/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 bpf bpf/ https://lore.kernel.org/bpf \
		bpf@vger.kernel.org
	public-inbox-index bpf

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.bpf


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git