tools/testing/selftests/bpf/prog_tests/cgrp_local_storage.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates.*/

#define _GNU_SOURCE
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <test_progs.h>
#include "cgrp_ls_tp_btf.skel.h"
#include "cgrp_ls_recursion.skel.h"
#include "cgrp_ls_attach_cgroup.skel.h"
#include "cgrp_ls_negative.skel.h"
#include "network_helpers.h"

struct socket_cookie {
	__u64 cookie_key;
	__u32 cookie_value;
};

static void test_tp_btf(int cgroup_fd)
{
	struct cgrp_ls_tp_btf *skel;
	long val1 = 1, val2 = 0;
	int err;

	skel = cgrp_ls_tp_btf__open_and_load();
	if (!ASSERT_OK_PTR(skel, "skel_open_and_load"))
		return;

	/* populate a value in map_b */
	err = bpf_map_update_elem(bpf_map__fd(skel->maps.map_b), &cgroup_fd, &val1, BPF_ANY);
	if (!ASSERT_OK(err, "map_update_elem"))
		goto out;

	/* check value */
	err = bpf_map_lookup_elem(bpf_map__fd(skel->maps.map_b), &cgroup_fd, &val2);
	if (!ASSERT_OK(err, "map_lookup_elem"))
		goto out;
	if (!ASSERT_EQ(val2, 1, "map_lookup_elem, invalid val"))
		goto out;

	/* delete value */
	err = bpf_map_delete_elem(bpf_map__fd(skel->maps.map_b), &cgroup_fd);
	if (!ASSERT_OK(err, "map_delete_elem"))
		goto out;

	skel->bss->target_pid = syscall(SYS_gettid);

	err = cgrp_ls_tp_btf__attach(skel);
	if (!ASSERT_OK(err, "skel_attach"))
		goto out;

	syscall(SYS_gettid);
	syscall(SYS_gettid);

	skel->bss->target_pid = 0;

	/* 3x syscalls: 1x attach and 2x gettid */
	ASSERT_EQ(skel->bss->enter_cnt, 3, "enter_cnt");
	ASSERT_EQ(skel->bss->exit_cnt, 3, "exit_cnt");
	ASSERT_EQ(skel->bss->mismatch_cnt, 0, "mismatch_cnt");
out:
	cgrp_ls_tp_btf__destroy(skel);
}

static void test_attach_cgroup(int cgroup_fd)
{
	int server_fd = 0, client_fd = 0, err = 0;
	socklen_t addr_len = sizeof(struct sockaddr_in6);
	struct cgrp_ls_attach_cgroup *skel;
	__u32 cookie_expected_value;
	struct sockaddr_in6 addr;
	struct socket_cookie val;

	skel = cgrp_ls_attach_cgroup__open_and_load();
	if (!ASSERT_OK_PTR(skel, "skel_open"))
		return;

	skel->links.set_cookie = bpf_program__attach_cgroup(
		skel->progs.set_cookie, cgroup_fd);
	if (!ASSERT_OK_PTR(skel->links.set_cookie, "prog_attach"))
		goto out;

	skel->links.update_cookie_sockops = bpf_program__attach_cgroup(
		skel->progs.update_cookie_sockops, cgroup_fd);
	if (!ASSERT_OK_PTR(skel->links.update_cookie_sockops, "prog_attach"))
		goto out;

	skel->links.update_cookie_tracing = bpf_program__attach(
		skel->progs.update_cookie_tracing);
	if (!ASSERT_OK_PTR(skel->links.update_cookie_tracing, "prog_attach"))
		goto out;

	server_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0);
	if (!ASSERT_GE(server_fd, 0, "start_server"))
		goto out;

	client_fd = connect_to_fd(server_fd, 0);
	if (!ASSERT_GE(client_fd, 0, "connect_to_fd"))
		goto close_server_fd;

	err = bpf_map_lookup_elem(bpf_map__fd(skel->maps.socket_cookies),
				  &cgroup_fd, &val);
	if (!ASSERT_OK(err, "map_lookup(socket_cookies)"))
		goto close_client_fd;

	err = getsockname(client_fd, (struct sockaddr *)&addr, &addr_len);
	if (!ASSERT_OK(err, "getsockname"))
		goto close_client_fd;

	cookie_expected_value = (ntohs(addr.sin6_port) << 8) | 0xFF;
	ASSERT_EQ(val.cookie_value, cookie_expected_value, "cookie_value");

close_client_fd:
	close(client_fd);
close_server_fd:
	close(server_fd);
out:
	cgrp_ls_attach_cgroup__destroy(skel);
}

static void test_recursion(int cgroup_fd)
{
	struct cgrp_ls_recursion *skel;
	int err;

	skel = cgrp_ls_recursion__open_and_load();
	if (!ASSERT_OK_PTR(skel, "skel_open_and_load"))
		return;

	err = cgrp_ls_recursion__attach(skel);
	if (!ASSERT_OK(err, "skel_attach"))
		goto out;

	/* trigger sys_enter, make sure it does not cause deadlock */
	syscall(SYS_gettid);

out:
	cgrp_ls_recursion__destroy(skel);
}

static void test_negative(void)
{
	struct cgrp_ls_negative *skel;

	skel = cgrp_ls_negative__open_and_load();
	if (!ASSERT_ERR_PTR(skel, "skel_open_and_load")) {
		cgrp_ls_negative__destroy(skel);
		return;
	}
}

void test_cgrp_local_storage(void)
{
	int cgroup_fd;

	cgroup_fd = test__join_cgroup("/cgrp_local_storage");
	if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup /cgrp_local_storage"))
		return;

	if (test__start_subtest("tp_btf"))
		test_tp_btf(cgroup_fd);
	if (test__start_subtest("attach_cgroup"))
		test_attach_cgroup(cgroup_fd);
	if (test__start_subtest("recursion"))
		test_recursion(cgroup_fd);
	if (test__start_subtest("negative"))
		test_negative();

	close(cgroup_fd);
}