// 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] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* check that the program is correctly loaded */
        ASSERT_EQ(self->skel->data->callback_check, 52) TH_LOG("callback_check1");
        ASSERT_EQ(self->skel->data->callback2_check, 52) TH_LOG("callback2_check1");

        /* inject one event */
        buf[0] = 1;
        buf[1] = 42;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* check that hid_first_event() was executed */
        ASSERT_EQ(self->skel->data->callback_check, 42) TH_LOG("callback_check1");

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 1);
        ASSERT_EQ(buf[2], 47);

        /* inject another event */
        memset(buf, 0, sizeof(buf));
        buf[0] = 1;
        buf[1] = 47;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* check that hid_first_event() was executed */
        ASSERT_EQ(self->skel->data->callback_check, 47) TH_LOG("callback_check1");

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[2], 52);
}

/*
 * 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, subprog_raw_event)
{
        const struct test_program progs[] = {
                { .name = "hid_subprog_first_event" },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* inject one event */
        buf[0] = 1;
        buf[1] = 42;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 1);
        ASSERT_EQ(buf[2], 47);

        /* inject another event */
        memset(buf, 0, sizeof(buf));
        buf[0] = 1;
        buf[1] = 47;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[2], 52);
}

/*
 * Attach hid_first_event to the given uhid device,
 * attempt at re-attaching it, we should not lock and
 * return an invalid struct bpf_link
 */
TEST_F(hid_bpf, multiple_attach)
{
        const struct test_program progs[] = {
                { .name = "hid_first_event" },
        };
        struct bpf_link *link;

        LOAD_PROGRAMS(progs);

        link = bpf_map__attach_struct_ops(self->skel->maps.first_event);
        ASSERT_NULL(link) TH_LOG("unexpected return value when re-attaching the struct_ops");
}

/*
 * Ensures that we can attach/detach programs
 */
TEST_F(hid_bpf, test_attach_detach)
{
        const struct test_program progs[] = {
                { .name = "hid_first_event" },
                { .name = "hid_second_event" },
        };
        struct bpf_link *link;
        __u8 buf[10] = {0};
        int err, link_fd;

        LOAD_PROGRAMS(progs);

        link = self->hid_links[0];
        ASSERT_OK_PTR(link) TH_LOG("HID-BPF link not created");

        link_fd = bpf_link__fd(link);
        ASSERT_GE(link_fd, 0) TH_LOG("HID-BPF link FD not valid");

        /* inject one event */
        buf[0] = 1;
        buf[1] = 42;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 1);
        ASSERT_EQ(buf[2], 47);

        /* make sure both programs are run */
        ASSERT_EQ(buf[3], 52);

        /* pin the first program and immediately unpin it */
#define PIN_PATH "/sys/fs/bpf/hid_first_event"
        err = bpf_obj_pin(link_fd, PIN_PATH);
        ASSERT_OK(err) TH_LOG("error while calling bpf_obj_pin");
        remove(PIN_PATH);
#undef PIN_PATH
        usleep(100000);

        /* detach the program */
        detach_bpf(self);

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

        /* inject another event */
        memset(buf, 0, sizeof(buf));
        buf[0] = 1;
        buf[1] = 47;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw_no_bpf");
        ASSERT_EQ(buf[0], 1);
        ASSERT_EQ(buf[1], 47);
        ASSERT_EQ(buf[2], 0);
        ASSERT_EQ(buf[3], 0);

        /* re-attach our program */

        LOAD_PROGRAMS(progs);

        /* inject one event */
        memset(buf, 0, sizeof(buf));
        buf[0] = 1;
        buf[1] = 42;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 1);
        ASSERT_EQ(buf[2], 47);
        ASSERT_EQ(buf[3], 52);
}

/*
 * Attach hid_change_report_id 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, test_hid_change_report)
{
        const struct test_program progs[] = {
                { .name = "hid_change_report_id" },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* inject one event */
        buf[0] = 1;
        buf[1] = 42;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 9) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 2);
        ASSERT_EQ(buf[1], 42);
        ASSERT_EQ(buf[2], 0) TH_LOG("leftovers_from_previous_test");
}

/*
 * Call hid_bpf_input_report against the given uhid device,
 * check that the program is called and does the expected.
 */
TEST_F(hid_bpf, test_hid_user_input_report_call)
{
        struct hid_hw_request_syscall_args args = {
                .retval = -1,
                .size = 10,
        };
        DECLARE_LIBBPF_OPTS(bpf_test_run_opts, tattrs,
                            .ctx_in = &args,
                            .ctx_size_in = sizeof(args),
        );
        __u8 buf[10] = {0};
        int err, prog_fd;

        LOAD_BPF;

        args.hid = self->hid.hid_id;
        args.data[0] = 1; /* report ID */
        args.data[1] = 2; /* report ID */
        args.data[2] = 42; /* report ID */

        prog_fd = bpf_program__fd(self->skel->progs.hid_user_input_report);

        /* check that there is no data to read from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, -1) TH_LOG("read_hidraw");

        err = bpf_prog_test_run_opts(prog_fd, &tattrs);

        ASSERT_OK(err) TH_LOG("error while calling bpf_prog_test_run_opts");

        ASSERT_EQ(args.retval, 0);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 1);
        ASSERT_EQ(buf[1], 2);
        ASSERT_EQ(buf[2], 42);
}

/*
 * Call hid_bpf_hw_output_report against the given uhid device,
 * check that the program is called and does the expected.
 */
TEST_F(hid_bpf, test_hid_user_output_report_call)
{
        struct hid_hw_request_syscall_args args = {
                .retval = -1,
                .size = 10,
        };
        DECLARE_LIBBPF_OPTS(bpf_test_run_opts, tattrs,
                            .ctx_in = &args,
                            .ctx_size_in = sizeof(args),
        );
        int err, cond_err, prog_fd;
        struct timespec time_to_wait;

        LOAD_BPF;

        args.hid = self->hid.hid_id;
        args.data[0] = 1; /* report ID */
        args.data[1] = 2; /* report ID */
        args.data[2] = 42; /* report ID */

        prog_fd = bpf_program__fd(self->skel->progs.hid_user_output_report);

        pthread_mutex_lock(&uhid_output_mtx);

        memset(output_report, 0, sizeof(output_report));
        clock_gettime(CLOCK_REALTIME, &time_to_wait);
        time_to_wait.tv_sec += 2;

        err = bpf_prog_test_run_opts(prog_fd, &tattrs);
        cond_err = pthread_cond_timedwait(&uhid_output_cond, &uhid_output_mtx, &time_to_wait);

        ASSERT_OK(err) TH_LOG("error while calling bpf_prog_test_run_opts");
        ASSERT_OK(cond_err) TH_LOG("error while calling waiting for the condition");

        ASSERT_EQ(args.retval, 3);

        ASSERT_EQ(output_report[0], 1);
        ASSERT_EQ(output_report[1], 2);
        ASSERT_EQ(output_report[2], 42);

        pthread_mutex_unlock(&uhid_output_mtx);
}

/*
 * Call hid_hw_raw_request against the given uhid device,
 * check that the program is called and does the expected.
 */
TEST_F(hid_bpf, test_hid_user_raw_request_call)
{
        struct hid_hw_request_syscall_args args = {
                .retval = -1,
                .type = HID_FEATURE_REPORT,
                .request_type = HID_REQ_GET_REPORT,
                .size = 10,
        };
        DECLARE_LIBBPF_OPTS(bpf_test_run_opts, tattrs,
                            .ctx_in = &args,
                            .ctx_size_in = sizeof(args),
        );
        int err, prog_fd;

        LOAD_BPF;

        args.hid = self->hid.hid_id;
        args.data[0] = 1; /* report ID */

        prog_fd = bpf_program__fd(self->skel->progs.hid_user_raw_request);

        err = bpf_prog_test_run_opts(prog_fd, &tattrs);
        ASSERT_OK(err) TH_LOG("error while calling bpf_prog_test_run_opts");

        ASSERT_EQ(args.retval, 2);

        ASSERT_EQ(args.data[1], 2);
}

/*
 * Call hid_hw_raw_request against the given uhid device,
 * check that the program is called and prevents the
 * call to uhid.
 */
TEST_F(hid_bpf, test_hid_filter_raw_request_call)
{
        const struct test_program progs[] = {
                { .name = "hid_test_filter_raw_request" },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* first check that we did not attach to device_event */

        /* inject one event */
        buf[0] = 1;
        buf[1] = 42;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 1);
        ASSERT_EQ(buf[1], 42);
        ASSERT_EQ(buf[2], 0) TH_LOG("leftovers_from_previous_test");

        /* now check that our program is preventing hid_hw_raw_request() */

        /* emit hid_hw_raw_request from hidraw */
        /* Get Feature */
        memset(buf, 0, sizeof(buf));
        buf[0] = 0x1; /* Report Number */
        err = ioctl(self->hidraw_fd, HIDIOCGFEATURE(sizeof(buf)), buf);
        ASSERT_LT(err, 0) TH_LOG("unexpected success while reading HIDIOCGFEATURE: %d", err);
        ASSERT_EQ(errno, 20) TH_LOG("unexpected error code while reading HIDIOCGFEATURE: %d",
                                    errno);

        /* remove our bpf program and check that we can now emit commands */

        /* detach the program */
        detach_bpf(self);

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

        err = ioctl(self->hidraw_fd, HIDIOCGFEATURE(sizeof(buf)), buf);
        ASSERT_GE(err, 0) TH_LOG("error while reading HIDIOCGFEATURE: %d", err);
}

/*
 * Call hid_hw_raw_request against the given uhid device,
 * check that the program is called and can issue the call
 * to uhid and transform the answer.
 */
TEST_F(hid_bpf, test_hid_change_raw_request_call)
{
        const struct test_program progs[] = {
                { .name = "hid_test_hidraw_raw_request" },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* emit hid_hw_raw_request from hidraw */
        /* Get Feature */
        memset(buf, 0, sizeof(buf));
        buf[0] = 0x1; /* Report Number */
        err = ioctl(self->hidraw_fd, HIDIOCGFEATURE(sizeof(buf)), buf);
        ASSERT_EQ(err, 3) TH_LOG("unexpected returned size while reading HIDIOCGFEATURE: %d", err);

        ASSERT_EQ(buf[0], 2);
        ASSERT_EQ(buf[1], 3);
        ASSERT_EQ(buf[2], 4);
}

/*
 * Call hid_hw_raw_request against the given uhid device,
 * check that the program is not making infinite loops.
 */
TEST_F(hid_bpf, test_hid_infinite_loop_raw_request_call)
{
        const struct test_program progs[] = {
                { .name = "hid_test_infinite_loop_raw_request" },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* emit hid_hw_raw_request from hidraw */
        /* Get Feature */
        memset(buf, 0, sizeof(buf));
        buf[0] = 0x1; /* Report Number */
        err = ioctl(self->hidraw_fd, HIDIOCGFEATURE(sizeof(buf)), buf);
        ASSERT_EQ(err, 3) TH_LOG("unexpected returned size while reading HIDIOCGFEATURE: %d", err);
}

/*
 * Call hid_hw_output_report against the given uhid device,
 * check that the program is called and prevents the
 * call to uhid.
 */
TEST_F(hid_bpf, test_hid_filter_output_report_call)
{
        const struct test_program progs[] = {
                { .name = "hid_test_filter_output_report" },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* first check that we did not attach to device_event */

        /* inject one event */
        buf[0] = 1;
        buf[1] = 42;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 1);
        ASSERT_EQ(buf[1], 42);
        ASSERT_EQ(buf[2], 0) TH_LOG("leftovers_from_previous_test");

        /* now check that our program is preventing hid_hw_output_report() */

        buf[0] = 1; /* report ID */
        buf[1] = 2;
        buf[2] = 42;

        err = write(self->hidraw_fd, buf, 3);
        ASSERT_LT(err, 0) TH_LOG("unexpected success while sending hid_hw_output_report: %d", err);
        ASSERT_EQ(errno, 25) TH_LOG("unexpected error code while sending hid_hw_output_report: %d",
                                    errno);

        /* remove our bpf program and check that we can now emit commands */

        /* detach the program */
        detach_bpf(self);

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

        err = write(self->hidraw_fd, buf, 3);
        ASSERT_GE(err, 0) TH_LOG("error while sending hid_hw_output_report: %d", err);
}

/*
 * Call hid_hw_output_report against the given uhid device,
 * check that the program is called and can issue the call
 * to uhid and transform the answer.
 */
TEST_F(hid_bpf, test_hid_change_output_report_call)
{
        const struct test_program progs[] = {
                { .name = "hid_test_hidraw_output_report" },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* emit hid_hw_output_report from hidraw */
        buf[0] = 1; /* report ID */
        buf[1] = 2;
        buf[2] = 42;

        err = write(self->hidraw_fd, buf, 10);
        ASSERT_EQ(err, 2) TH_LOG("unexpected returned size while sending hid_hw_output_report: %d",
                                 err);
}

/*
 * Call hid_hw_output_report against the given uhid device,
 * check that the program is not making infinite loops.
 */
TEST_F(hid_bpf, test_hid_infinite_loop_output_report_call)
{
        const struct test_program progs[] = {
                { .name = "hid_test_infinite_loop_output_report" },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* emit hid_hw_output_report from hidraw */
        buf[0] = 1; /* report ID */
        buf[1] = 2;
        buf[2] = 42;

        err = write(self->hidraw_fd, buf, 8);
        ASSERT_EQ(err, 2) TH_LOG("unexpected returned size while sending hid_hw_output_report: %d",
                                 err);
}

/*
 * Attach hid_multiply_event_wq 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 add extra data
 */
TEST_F(hid_bpf, test_multiply_events_wq)
{
        const struct test_program progs[] = {
                { .name = "hid_test_multiply_events_wq" },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* inject one event */
        buf[0] = 1;
        buf[1] = 42;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 1);
        ASSERT_EQ(buf[1], 47);

        usleep(100000);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 9) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 2);
        ASSERT_EQ(buf[1], 3);
}

/*
 * Attach hid_multiply_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 add extra data
 */
TEST_F(hid_bpf, test_multiply_events)
{
        const struct test_program progs[] = {
                { .name = "hid_test_multiply_events" },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* inject one event */
        buf[0] = 1;
        buf[1] = 42;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 9) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 2);
        ASSERT_EQ(buf[1], 47);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 9) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 2);
        ASSERT_EQ(buf[1], 52);
}

/*
 * Call hid_bpf_input_report against the given uhid device,
 * check that the program is not making infinite loops.
 */
TEST_F(hid_bpf, test_hid_infinite_loop_input_report_call)
{
        const struct test_program progs[] = {
                { .name = "hid_test_infinite_loop_input_report" },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* emit hid_hw_output_report from hidraw */
        buf[0] = 1; /* report ID */
        buf[1] = 2;
        buf[2] = 42;

        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 1);
        ASSERT_EQ(buf[1], 3);

        /* read the data from hidraw: hid_bpf_try_input_report should work exactly one time */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[0], 1);
        ASSERT_EQ(buf[1], 4);

        /* read the data from hidraw: there should be none */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, -1) TH_LOG("read_hidraw");
}

/*
 * Attach hid_insert{0,1,2} to the given uhid device,
 * retrieve and open the matching hidraw node,
 * inject one event in the uhid device,
 * check that the programs have been inserted in the correct order.
 */
TEST_F(hid_bpf, test_hid_attach_flags)
{
        const struct test_program progs[] = {
                {
                        .name = "hid_test_insert2",
                        .insert_head = 0,
                },
                {
                        .name = "hid_test_insert1",
                        .insert_head = 1,
                },
                {
                        .name = "hid_test_insert3",
                        .insert_head = 0,
                },
        };
        __u8 buf[10] = {0};
        int err;

        LOAD_PROGRAMS(progs);

        /* inject one event */
        buf[0] = 1;
        uhid_send_event(_metadata, &self->hid, buf, 6);

        /* read the data from hidraw */
        memset(buf, 0, sizeof(buf));
        err = read(self->hidraw_fd, buf, sizeof(buf));
        ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
        ASSERT_EQ(buf[1], 1);
        ASSERT_EQ(buf[2], 2);
        ASSERT_EQ(buf[3], 3);
}

/*
 * Attach hid_rdesc_fixup to the given uhid device,
 * retrieve and open the matching hidraw node,
 * check that the hidraw report descriptor has been updated.
 */
TEST_F(hid_bpf, test_rdesc_fixup)
{
        struct hidraw_report_descriptor rpt_desc = {0};
        const struct test_program progs[] = {
                { .name = "hid_rdesc_fixup" },
        };
        int err, desc_size;

        LOAD_PROGRAMS(progs);

        /* check that hid_rdesc_fixup() was executed */
        ASSERT_EQ(self->skel->data->callback2_check, 0x21);

        /* read the exposed report descriptor from hidraw */
        err = ioctl(self->hidraw_fd, HIDIOCGRDESCSIZE, &desc_size);
        ASSERT_GE(err, 0) TH_LOG("error while reading HIDIOCGRDESCSIZE: %d", err);

        /* ensure the new size of the rdesc is bigger than the old one */
        ASSERT_GT(desc_size, sizeof(rdesc));

        rpt_desc.size = desc_size;
        err = ioctl(self->hidraw_fd, HIDIOCGRDESC, &rpt_desc);
        ASSERT_GE(err, 0) TH_LOG("error while reading HIDIOCGRDESC: %d", err);

        ASSERT_EQ(rpt_desc.value[4], 0x42);
}

static int libbpf_print_fn(enum libbpf_print_level level,
                           const char *format, va_list args)
{
        char buf[1024];

        if (level == LIBBPF_DEBUG)
                return 0;

        snprintf(buf, sizeof(buf), "# %s", format);

        vfprintf(stdout, buf, args);
        return 0;
}

int main(int argc, char **argv)
{
        /* Use libbpf 1.0 API mode */
        libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
        libbpf_set_print(libbpf_print_fn);

        return test_harness_run(argc, argv);
}