path: root/tools/testing/selftests/hid/hid_bpf.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2022-2024 Red Hat */
#include "hid.skel.h"
#include "hid_common.h"
#include <bpf/bpf.h>

struct hid_hw_request_syscall_args {
	__u8 data[10];
	unsigned int hid;
	int retval;
	size_t size;
	enum hid_report_type type;
	__u8 request_type;
};

FIXTURE(hid_bpf) {
	struct uhid_device hid;
	int hidraw_fd;
	struct hid *skel;
	struct bpf_link *hid_links[3]; /* max number of programs loaded in a single test */
};
static void detach_bpf(FIXTURE_DATA(hid_bpf) * self)
{
	int i;

	if (self->hidraw_fd)
		close(self->hidraw_fd);
	self->hidraw_fd = 0;

	if (!self->skel)
		return;

	hid__detach(self->skel);

	for (i = 0; i < ARRAY_SIZE(self->hid_links); i++) {
		if (self->hid_links[i])
			bpf_link__destroy(self->hid_links[i]);
	}

	hid__destroy(self->skel);
	self->skel = NULL;
}

FIXTURE_TEARDOWN(hid_bpf) {
	void *uhid_err;

	uhid_destroy(_metadata, &self->hid);

	detach_bpf(self);
	pthread_join(self->hid.tid, &uhid_err);
}
#define TEARDOWN_LOG(fmt, ...) do { \
	TH_LOG(fmt, ##__VA_ARGS__); \
	hid_bpf_teardown(_metadata, self, variant); \
} while (0)

FIXTURE_SETUP(hid_bpf)
{
	int err;

	err = setup_uhid(_metadata, &self->hid, BUS_USB, 0x0001, 0x0a36, rdesc, sizeof(rdesc));
	ASSERT_OK(err);
}

struct test_program {
	const char *name;
	int insert_head;
};
#define LOAD_PROGRAMS(progs) \
	load_programs(progs, ARRAY_SIZE(progs), _metadata, self, variant)
#define LOAD_BPF \
	load_programs(NULL, 0, _metadata, self, variant)
static void load_programs(const struct test_program programs[],
			  const size_t progs_count,
			  struct __test_metadata *_metadata,
			  FIXTURE_DATA(hid_bpf) * self,
			  const FIXTURE_VARIANT(hid_bpf) * variant)
{
	struct bpf_map *iter_map;
	int err = -EINVAL;

	ASSERT_LE(progs_count, ARRAY_SIZE(self->hid_links))
		TH_LOG("too many programs are to be loaded");

	/* open the bpf file */
	self->skel = hid__open();
	ASSERT_OK_PTR(self->skel) TEARDOWN_LOG("Error while calling hid__open");

	for (int i = 0; i < progs_count; i++) {
		struct bpf_program *prog;
		struct bpf_map *map;
		int *ops_hid_id;

		prog = bpf_object__find_program_by_name(*self->skel->skeleton->obj,
							programs[i].name);
		ASSERT_OK_PTR(prog) TH_LOG("can not find program by name '%s'", programs[i].name);

		bpf_program__set_autoload(prog, true);

		map = bpf_object__find_map_by_name(*self->skel->skeleton->obj,
							  programs[i].name + 4);
		ASSERT_OK_PTR(map) TH_LOG("can not find struct_ops by name '%s'",
					  programs[i].name + 4);

		/* hid_id is the first field of struct hid_bpf_ops */
		ops_hid_id = bpf_map__initial_value(map, NULL);
		ASSERT_OK_PTR(ops_hid_id) TH_LOG("unable to retrieve struct_ops data");

		*ops_hid_id = self->hid.hid_id;
	}

	/* we disable the auto-attach feature of all maps because we
	 * only want the tested one to be manually attached in the next
	 * call to bpf_map__attach_struct_ops()
	 */
	bpf_object__for_each_map(iter_map, *self->skel->skeleton->obj)
		bpf_map__set_autoattach(iter_map, false);

	err = hid__load(self->skel);
	ASSERT_OK(err) TH_LOG("hid_skel_load failed: %d", err);

	for (int i = 0; i < progs_count; i++) {
		struct bpf_map *map;

		map = bpf_object__find_map_by_name(*self->skel->skeleton->obj,
							  programs[i].name + 4);
		ASSERT_OK_PTR(map) TH_LOG("can not find struct_ops by name '%s'",
					  programs[i].name + 4);

		self->hid_links[i] = bpf_map__attach_struct_ops(map);
		ASSERT_OK_PTR(self->hid_links[i]) TH_LOG("failed to attach struct ops '%s'",
							 programs[i].name + 4);
	}

	hid__attach(self->skel);

	self->hidraw_fd = open_hidraw(&self->hid);
	ASSERT_GE(self->hidraw_fd, 0) TH_LOG("open_hidraw");
}

/*
 * A simple test to see if the fixture is working fine.
 * If this fails, none of the other tests will pass.
 */
TEST_F(hid_bpf, test_create_uhid)
{
}

/*
 * Attach hid_first_event to the given uhid device,
 * retrieve and open the matching hidraw node,
 * inject one event in the uhid device,
 * check that the program sees it and can change the data
 */
TEST_F(hid_bpf, raw_event)
{
	const struct test_program progs[] = {
		{ .name = "hid_first_event" },
	};
	__u8 buf[10]