xref: /linux/tools/testing/selftests/hid/hid_bpf.c (revision 0330f725cc5b01f4149a2a21e474b2090a1dcead)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2022 Red Hat */
3 #include "hid.skel.h"
4 
5 #include "../kselftest_harness.h"
6 
7 #include <bpf/bpf.h>
8 #include <fcntl.h>
9 #include <fnmatch.h>
10 #include <dirent.h>
11 #include <poll.h>
12 #include <pthread.h>
13 #include <stdbool.h>
14 #include <linux/hidraw.h>
15 #include <linux/uhid.h>
16 
17 #define SHOW_UHID_DEBUG 0
18 
19 static unsigned char rdesc[] = {
20 	0x06, 0x00, 0xff,	/* Usage Page (Vendor Defined Page 1) */
21 	0x09, 0x21,		/* Usage (Vendor Usage 0x21) */
22 	0xa1, 0x01,		/* COLLECTION (Application) */
23 	0x09, 0x01,			/* Usage (Vendor Usage 0x01) */
24 	0xa1, 0x00,			/* COLLECTION (Physical) */
25 	0x85, 0x02,				/* REPORT_ID (2) */
26 	0x19, 0x01,				/* USAGE_MINIMUM (1) */
27 	0x29, 0x08,				/* USAGE_MAXIMUM (3) */
28 	0x15, 0x00,				/* LOGICAL_MINIMUM (0) */
29 	0x25, 0xff,				/* LOGICAL_MAXIMUM (255) */
30 	0x95, 0x08,				/* REPORT_COUNT (8) */
31 	0x75, 0x08,				/* REPORT_SIZE (8) */
32 	0x81, 0x02,				/* INPUT (Data,Var,Abs) */
33 	0xc0,				/* END_COLLECTION */
34 	0x09, 0x01,			/* Usage (Vendor Usage 0x01) */
35 	0xa1, 0x00,			/* COLLECTION (Physical) */
36 	0x85, 0x01,				/* REPORT_ID (1) */
37 	0x06, 0x00, 0xff,			/* Usage Page (Vendor Defined Page 1) */
38 	0x19, 0x01,				/* USAGE_MINIMUM (1) */
39 	0x29, 0x03,				/* USAGE_MAXIMUM (3) */
40 	0x15, 0x00,				/* LOGICAL_MINIMUM (0) */
41 	0x25, 0x01,				/* LOGICAL_MAXIMUM (1) */
42 	0x95, 0x03,				/* REPORT_COUNT (3) */
43 	0x75, 0x01,				/* REPORT_SIZE (1) */
44 	0x81, 0x02,				/* INPUT (Data,Var,Abs) */
45 	0x95, 0x01,				/* REPORT_COUNT (1) */
46 	0x75, 0x05,				/* REPORT_SIZE (5) */
47 	0x81, 0x01,				/* INPUT (Cnst,Var,Abs) */
48 	0x05, 0x01,				/* USAGE_PAGE (Generic Desktop) */
49 	0x09, 0x30,				/* USAGE (X) */
50 	0x09, 0x31,				/* USAGE (Y) */
51 	0x15, 0x81,				/* LOGICAL_MINIMUM (-127) */
52 	0x25, 0x7f,				/* LOGICAL_MAXIMUM (127) */
53 	0x75, 0x10,				/* REPORT_SIZE (16) */
54 	0x95, 0x02,				/* REPORT_COUNT (2) */
55 	0x81, 0x06,				/* INPUT (Data,Var,Rel) */
56 
57 	0x06, 0x00, 0xff,			/* Usage Page (Vendor Defined Page 1) */
58 	0x19, 0x01,				/* USAGE_MINIMUM (1) */
59 	0x29, 0x03,				/* USAGE_MAXIMUM (3) */
60 	0x15, 0x00,				/* LOGICAL_MINIMUM (0) */
61 	0x25, 0x01,				/* LOGICAL_MAXIMUM (1) */
62 	0x95, 0x03,				/* REPORT_COUNT (3) */
63 	0x75, 0x01,				/* REPORT_SIZE (1) */
64 	0x91, 0x02,				/* Output (Data,Var,Abs) */
65 	0x95, 0x01,				/* REPORT_COUNT (1) */
66 	0x75, 0x05,				/* REPORT_SIZE (5) */
67 	0x91, 0x01,				/* Output (Cnst,Var,Abs) */
68 
69 	0x06, 0x00, 0xff,			/* Usage Page (Vendor Defined Page 1) */
70 	0x19, 0x06,				/* USAGE_MINIMUM (6) */
71 	0x29, 0x08,				/* USAGE_MAXIMUM (8) */
72 	0x15, 0x00,				/* LOGICAL_MINIMUM (0) */
73 	0x25, 0x01,				/* LOGICAL_MAXIMUM (1) */
74 	0x95, 0x03,				/* REPORT_COUNT (3) */
75 	0x75, 0x01,				/* REPORT_SIZE (1) */
76 	0xb1, 0x02,				/* Feature (Data,Var,Abs) */
77 	0x95, 0x01,				/* REPORT_COUNT (1) */
78 	0x75, 0x05,				/* REPORT_SIZE (5) */
79 	0x91, 0x01,				/* Output (Cnst,Var,Abs) */
80 
81 	0xc0,				/* END_COLLECTION */
82 	0xc0,			/* END_COLLECTION */
83 };
84 
85 struct attach_prog_args {
86 	int prog_fd;
87 	unsigned int hid;
88 	int retval;
89 };
90 
91 #define ASSERT_OK(data) ASSERT_FALSE(data)
92 #define ASSERT_OK_PTR(ptr) ASSERT_NE(NULL, ptr)
93 
94 #define UHID_LOG(fmt, ...) do { \
95 	if (SHOW_UHID_DEBUG) \
96 		TH_LOG(fmt, ##__VA_ARGS__); \
97 } while (0)
98 
99 static pthread_mutex_t uhid_started_mtx = PTHREAD_MUTEX_INITIALIZER;
100 static pthread_cond_t uhid_started = PTHREAD_COND_INITIALIZER;
101 
102 /* no need to protect uhid_stopped, only one thread accesses it */
103 static bool uhid_stopped;
104 
105 static int uhid_write(struct __test_metadata *_metadata, int fd, const struct uhid_event *ev)
106 {
107 	ssize_t ret;
108 
109 	ret = write(fd, ev, sizeof(*ev));
110 	if (ret < 0) {
111 		TH_LOG("Cannot write to uhid: %m");
112 		return -errno;
113 	} else if (ret != sizeof(*ev)) {
114 		TH_LOG("Wrong size written to uhid: %zd != %zu",
115 			ret, sizeof(ev));
116 		return -EFAULT;
117 	} else {
118 		return 0;
119 	}
120 }
121 
122 static int uhid_create(struct __test_metadata *_metadata, int fd, int rand_nb)
123 {
124 	struct uhid_event ev;
125 	char buf[25];
126 
127 	sprintf(buf, "test-uhid-device-%d", rand_nb);
128 
129 	memset(&ev, 0, sizeof(ev));
130 	ev.type = UHID_CREATE;
131 	strcpy((char *)ev.u.create.name, buf);
132 	ev.u.create.rd_data = rdesc;
133 	ev.u.create.rd_size = sizeof(rdesc);
134 	ev.u.create.bus = BUS_USB;
135 	ev.u.create.vendor = 0x0001;
136 	ev.u.create.product = 0x0a37;
137 	ev.u.create.version = 0;
138 	ev.u.create.country = 0;
139 
140 	sprintf(buf, "%d", rand_nb);
141 	strcpy((char *)ev.u.create.phys, buf);
142 
143 	return uhid_write(_metadata, fd, &ev);
144 }
145 
146 static void uhid_destroy(struct __test_metadata *_metadata, int fd)
147 {
148 	struct uhid_event ev;
149 
150 	memset(&ev, 0, sizeof(ev));
151 	ev.type = UHID_DESTROY;
152 
153 	uhid_write(_metadata, fd, &ev);
154 }
155 
156 static int uhid_event(struct __test_metadata *_metadata, int fd)
157 {
158 	struct uhid_event ev;
159 	ssize_t ret;
160 
161 	memset(&ev, 0, sizeof(ev));
162 	ret = read(fd, &ev, sizeof(ev));
163 	if (ret == 0) {
164 		UHID_LOG("Read HUP on uhid-cdev");
165 		return -EFAULT;
166 	} else if (ret < 0) {
167 		UHID_LOG("Cannot read uhid-cdev: %m");
168 		return -errno;
169 	} else if (ret != sizeof(ev)) {
170 		UHID_LOG("Invalid size read from uhid-dev: %zd != %zu",
171 			ret, sizeof(ev));
172 		return -EFAULT;
173 	}
174 
175 	switch (ev.type) {
176 	case UHID_START:
177 		pthread_mutex_lock(&uhid_started_mtx);
178 		pthread_cond_signal(&uhid_started);
179 		pthread_mutex_unlock(&uhid_started_mtx);
180 
181 		UHID_LOG("UHID_START from uhid-dev");
182 		break;
183 	case UHID_STOP:
184 		uhid_stopped = true;
185 
186 		UHID_LOG("UHID_STOP from uhid-dev");
187 		break;
188 	case UHID_OPEN:
189 		UHID_LOG("UHID_OPEN from uhid-dev");
190 		break;
191 	case UHID_CLOSE:
192 		UHID_LOG("UHID_CLOSE from uhid-dev");
193 		break;
194 	case UHID_OUTPUT:
195 		UHID_LOG("UHID_OUTPUT from uhid-dev");
196 		break;
197 	case UHID_GET_REPORT:
198 		UHID_LOG("UHID_GET_REPORT from uhid-dev");
199 		break;
200 	case UHID_SET_REPORT:
201 		UHID_LOG("UHID_SET_REPORT from uhid-dev");
202 		break;
203 	default:
204 		TH_LOG("Invalid event from uhid-dev: %u", ev.type);
205 	}
206 
207 	return 0;
208 }
209 
210 struct uhid_thread_args {
211 	int fd;
212 	struct __test_metadata *_metadata;
213 };
214 static void *uhid_read_events_thread(void *arg)
215 {
216 	struct uhid_thread_args *args = (struct uhid_thread_args *)arg;
217 	struct __test_metadata *_metadata = args->_metadata;
218 	struct pollfd pfds[1];
219 	int fd = args->fd;
220 	int ret = 0;
221 
222 	pfds[0].fd = fd;
223 	pfds[0].events = POLLIN;
224 
225 	uhid_stopped = false;
226 
227 	while (!uhid_stopped) {
228 		ret = poll(pfds, 1, 100);
229 		if (ret < 0) {
230 			TH_LOG("Cannot poll for fds: %m");
231 			break;
232 		}
233 		if (pfds[0].revents & POLLIN) {
234 			ret = uhid_event(_metadata, fd);
235 			if (ret)
236 				break;
237 		}
238 	}
239 
240 	return (void *)(long)ret;
241 }
242 
243 static int uhid_start_listener(struct __test_metadata *_metadata, pthread_t *tid, int uhid_fd)
244 {
245 	struct uhid_thread_args args = {
246 		.fd = uhid_fd,
247 		._metadata = _metadata,
248 	};
249 	int err;
250 
251 	pthread_mutex_lock(&uhid_started_mtx);
252 	err = pthread_create(tid, NULL, uhid_read_events_thread, (void *)&args);
253 	ASSERT_EQ(0, err) {
254 		TH_LOG("Could not start the uhid thread: %d", err);
255 		pthread_mutex_unlock(&uhid_started_mtx);
256 		close(uhid_fd);
257 		return -EIO;
258 	}
259 	pthread_cond_wait(&uhid_started, &uhid_started_mtx);
260 	pthread_mutex_unlock(&uhid_started_mtx);
261 
262 	return 0;
263 }
264 
265 static int uhid_send_event(struct __test_metadata *_metadata, int fd, __u8 *buf, size_t size)
266 {
267 	struct uhid_event ev;
268 
269 	if (size > sizeof(ev.u.input.data))
270 		return -E2BIG;
271 
272 	memset(&ev, 0, sizeof(ev));
273 	ev.type = UHID_INPUT2;
274 	ev.u.input2.size = size;
275 
276 	memcpy(ev.u.input2.data, buf, size);
277 
278 	return uhid_write(_metadata, fd, &ev);
279 }
280 
281 static int setup_uhid(struct __test_metadata *_metadata, int rand_nb)
282 {
283 	int fd;
284 	const char *path = "/dev/uhid";
285 	int ret;
286 
287 	fd = open(path, O_RDWR | O_CLOEXEC);
288 	ASSERT_GE(fd, 0) TH_LOG("open uhid-cdev failed; %d", fd);
289 
290 	ret = uhid_create(_metadata, fd, rand_nb);
291 	ASSERT_EQ(0, ret) {
292 		TH_LOG("create uhid device failed: %d", ret);
293 		close(fd);
294 	}
295 
296 	return fd;
297 }
298 
299 static bool match_sysfs_device(int dev_id, const char *workdir, struct dirent *dir)
300 {
301 	const char *target = "0003:0001:0A37.*";
302 	char phys[512];
303 	char uevent[1024];
304 	char temp[512];
305 	int fd, nread;
306 	bool found = false;
307 
308 	if (fnmatch(target, dir->d_name, 0))
309 		return false;
310 
311 	/* we found the correct VID/PID, now check for phys */
312 	sprintf(uevent, "%s/%s/uevent", workdir, dir->d_name);
313 
314 	fd = open(uevent, O_RDONLY | O_NONBLOCK);
315 	if (fd < 0)
316 		return false;
317 
318 	sprintf(phys, "PHYS=%d", dev_id);
319 
320 	nread = read(fd, temp, ARRAY_SIZE(temp));
321 	if (nread > 0 && (strstr(temp, phys)) != NULL)
322 		found = true;
323 
324 	close(fd);
325 
326 	return found;
327 }
328 
329 static int get_hid_id(int dev_id)
330 {
331 	const char *workdir = "/sys/devices/virtual/misc/uhid";
332 	const char *str_id;
333 	DIR *d;
334 	struct dirent *dir;
335 	int found = -1, attempts = 3;
336 
337 	/* it would be nice to be able to use nftw, but the no_alu32 target doesn't support it */
338 
339 	while (found < 0 && attempts > 0) {
340 		attempts--;
341 		d = opendir(workdir);
342 		if (d) {
343 			while ((dir = readdir(d)) != NULL) {
344 				if (!match_sysfs_device(dev_id, workdir, dir))
345 					continue;
346 
347 				str_id = dir->d_name + sizeof("0003:0001:0A37.");
348 				found = (int)strtol(str_id, NULL, 16);
349 
350 				break;
351 			}
352 			closedir(d);
353 		}
354 		if (found < 0)
355 			usleep(100000);
356 	}
357 
358 	return found;
359 }
360 
361 static int get_hidraw(int dev_id)
362 {
363 	const char *workdir = "/sys/devices/virtual/misc/uhid";
364 	char sysfs[1024];
365 	DIR *d, *subd;
366 	struct dirent *dir, *subdir;
367 	int i, found = -1;
368 
369 	/* retry 5 times in case the system is loaded */
370 	for (i = 5; i > 0; i--) {
371 		usleep(10);
372 		d = opendir(workdir);
373 
374 		if (!d)
375 			continue;
376 
377 		while ((dir = readdir(d)) != NULL) {
378 			if (!match_sysfs_device(dev_id, workdir, dir))
379 				continue;
380 
381 			sprintf(sysfs, "%s/%s/hidraw", workdir, dir->d_name);
382 
383 			subd = opendir(sysfs);
384 			if (!subd)
385 				continue;
386 
387 			while ((subdir = readdir(subd)) != NULL) {
388 				if (fnmatch("hidraw*", subdir->d_name, 0))
389 					continue;
390 
391 				found = atoi(subdir->d_name + strlen("hidraw"));
392 			}
393 
394 			closedir(subd);
395 
396 			if (found > 0)
397 				break;
398 		}
399 		closedir(d);
400 	}
401 
402 	return found;
403 }
404 
405 static int open_hidraw(int dev_id)
406 {
407 	int hidraw_number;
408 	char hidraw_path[64] = { 0 };
409 
410 	hidraw_number = get_hidraw(dev_id);
411 	if (hidraw_number < 0)
412 		return hidraw_number;
413 
414 	/* open hidraw node to check the other side of the pipe */
415 	sprintf(hidraw_path, "/dev/hidraw%d", hidraw_number);
416 	return open(hidraw_path, O_RDWR | O_NONBLOCK);
417 }
418 
419 FIXTURE(hid_bpf) {
420 	int dev_id;
421 	int uhid_fd;
422 	int hidraw_fd;
423 	int hid_id;
424 	pthread_t tid;
425 	struct hid *skel;
426 };
427 static void detach_bpf(FIXTURE_DATA(hid_bpf) * self)
428 {
429 	if (self->hidraw_fd)
430 		close(self->hidraw_fd);
431 	self->hidraw_fd = 0;
432 
433 	hid__destroy(self->skel);
434 	self->skel = NULL;
435 }
436 
437 FIXTURE_TEARDOWN(hid_bpf) {
438 	void *uhid_err;
439 
440 	uhid_destroy(_metadata, self->uhid_fd);
441 
442 	detach_bpf(self);
443 	pthread_join(self->tid, &uhid_err);
444 }
445 #define TEARDOWN_LOG(fmt, ...) do { \
446 	TH_LOG(fmt, ##__VA_ARGS__); \
447 	hid_bpf_teardown(_metadata, self, variant); \
448 } while (0)
449 
450 FIXTURE_SETUP(hid_bpf)
451 {
452 	time_t t;
453 	int err;
454 
455 	/* initialize random number generator */
456 	srand((unsigned int)time(&t));
457 
458 	self->dev_id = rand() % 1024;
459 
460 	self->uhid_fd = setup_uhid(_metadata, self->dev_id);
461 
462 	/* locate the uev, self, variant);ent file of the created device */
463 	self->hid_id = get_hid_id(self->dev_id);
464 	ASSERT_GT(self->hid_id, 0)
465 		TEARDOWN_LOG("Could not locate uhid device id: %d", self->hid_id);
466 
467 	err = uhid_start_listener(_metadata, &self->tid, self->uhid_fd);
468 	ASSERT_EQ(0, err) TEARDOWN_LOG("could not start udev listener: %d", err);
469 }
470 
471 struct test_program {
472 	const char *name;
473 };
474 #define LOAD_PROGRAMS(progs) \
475 	load_programs(progs, ARRAY_SIZE(progs), _metadata, self, variant)
476 #define LOAD_BPF \
477 	load_programs(NULL, 0, _metadata, self, variant)
478 static void load_programs(const struct test_program programs[],
479 			  const size_t progs_count,
480 			  struct __test_metadata *_metadata,
481 			  FIXTURE_DATA(hid_bpf) * self,
482 			  const FIXTURE_VARIANT(hid_bpf) * variant)
483 {
484 	int attach_fd, err = -EINVAL;
485 	struct attach_prog_args args = {
486 		.retval = -1,
487 	};
488 	DECLARE_LIBBPF_OPTS(bpf_test_run_opts, tattr,
489 			    .ctx_in = &args,
490 			    .ctx_size_in = sizeof(args),
491 	);
492 
493 	/* open the bpf file */
494 	self->skel = hid__open();
495 	ASSERT_OK_PTR(self->skel) TEARDOWN_LOG("Error while calling hid__open");
496 
497 	for (int i = 0; i < progs_count; i++) {
498 		struct bpf_program *prog;
499 
500 		prog = bpf_object__find_program_by_name(*self->skel->skeleton->obj,
501 							programs[i].name);
502 		ASSERT_OK_PTR(prog) TH_LOG("can not find program by name '%s'", programs[i].name);
503 
504 		bpf_program__set_autoload(prog, true);
505 	}
506 
507 	err = hid__load(self->skel);
508 	ASSERT_OK(err) TH_LOG("hid_skel_load failed: %d", err);
509 
510 	attach_fd = bpf_program__fd(self->skel->progs.attach_prog);
511 	ASSERT_GE(attach_fd, 0) TH_LOG("locate attach_prog: %d", attach_fd);
512 
513 	for (int i = 0; i < progs_count; i++) {
514 		struct bpf_program *prog;
515 
516 		prog = bpf_object__find_program_by_name(*self->skel->skeleton->obj,
517 							programs[i].name);
518 		ASSERT_OK_PTR(prog) TH_LOG("can not find program by name '%s'", programs[i].name);
519 
520 		args.prog_fd = bpf_program__fd(prog);
521 		args.hid = self->hid_id;
522 		err = bpf_prog_test_run_opts(attach_fd, &tattr);
523 		ASSERT_OK(args.retval) TH_LOG("attach_hid(%s): %d", programs[i].name, args.retval);
524 	}
525 
526 	self->hidraw_fd = open_hidraw(self->dev_id);
527 	ASSERT_GE(self->hidraw_fd, 0) TH_LOG("open_hidraw");
528 }
529 
530 /*
531  * A simple test to see if the fixture is working fine.
532  * If this fails, none of the other tests will pass.
533  */
534 TEST_F(hid_bpf, test_create_uhid)
535 {
536 }
537 
538 /*
539  * Attach hid_first_event to the given uhid device,
540  * retrieve and open the matching hidraw node,
541  * inject one event in the uhid device,
542  * check that the program sees it and can change the data
543  */
544 TEST_F(hid_bpf, raw_event)
545 {
546 	const struct test_program progs[] = {
547 		{ .name = "hid_first_event" },
548 	};
549 	__u8 buf[10] = {0};
550 	int err;
551 
552 	LOAD_PROGRAMS(progs);
553 
554 	/* check that the program is correctly loaded */
555 	ASSERT_EQ(self->skel->data->callback_check, 52) TH_LOG("callback_check1");
556 	ASSERT_EQ(self->skel->data->callback2_check, 52) TH_LOG("callback2_check1");
557 
558 	/* inject one event */
559 	buf[0] = 1;
560 	buf[1] = 42;
561 	uhid_send_event(_metadata, self->uhid_fd, buf, 6);
562 
563 	/* check that hid_first_event() was executed */
564 	ASSERT_EQ(self->skel->data->callback_check, 42) TH_LOG("callback_check1");
565 
566 	/* read the data from hidraw */
567 	memset(buf, 0, sizeof(buf));
568 	err = read(self->hidraw_fd, buf, sizeof(buf));
569 	ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
570 	ASSERT_EQ(buf[0], 1);
571 	ASSERT_EQ(buf[2], 47);
572 
573 	/* inject another event */
574 	memset(buf, 0, sizeof(buf));
575 	buf[0] = 1;
576 	buf[1] = 47;
577 	uhid_send_event(_metadata, self->uhid_fd, buf, 6);
578 
579 	/* check that hid_first_event() was executed */
580 	ASSERT_EQ(self->skel->data->callback_check, 47) TH_LOG("callback_check1");
581 
582 	/* read the data from hidraw */
583 	memset(buf, 0, sizeof(buf));
584 	err = read(self->hidraw_fd, buf, sizeof(buf));
585 	ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
586 	ASSERT_EQ(buf[2], 52);
587 }
588 
589 /*
590  * Ensures that we can attach/detach programs
591  */
592 TEST_F(hid_bpf, test_attach_detach)
593 {
594 	const struct test_program progs[] = {
595 		{ .name = "hid_first_event" },
596 	};
597 	__u8 buf[10] = {0};
598 	int err;
599 
600 	LOAD_PROGRAMS(progs);
601 
602 	/* inject one event */
603 	buf[0] = 1;
604 	buf[1] = 42;
605 	uhid_send_event(_metadata, self->uhid_fd, buf, 6);
606 
607 	/* read the data from hidraw */
608 	memset(buf, 0, sizeof(buf));
609 	err = read(self->hidraw_fd, buf, sizeof(buf));
610 	ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
611 	ASSERT_EQ(buf[0], 1);
612 	ASSERT_EQ(buf[2], 47);
613 
614 	/* pin the program and immediately unpin it */
615 #define PIN_PATH "/sys/fs/bpf/hid_first_event"
616 	bpf_program__pin(self->skel->progs.hid_first_event, PIN_PATH);
617 	remove(PIN_PATH);
618 #undef PIN_PATH
619 	usleep(100000);
620 
621 	/* detach the program */
622 	detach_bpf(self);
623 
624 	self->hidraw_fd = open_hidraw(self->dev_id);
625 	ASSERT_GE(self->hidraw_fd, 0) TH_LOG("open_hidraw");
626 
627 	/* inject another event */
628 	memset(buf, 0, sizeof(buf));
629 	buf[0] = 1;
630 	buf[1] = 47;
631 	uhid_send_event(_metadata, self->uhid_fd, buf, 6);
632 
633 	/* read the data from hidraw */
634 	memset(buf, 0, sizeof(buf));
635 	err = read(self->hidraw_fd, buf, sizeof(buf));
636 	ASSERT_EQ(err, 6) TH_LOG("read_hidraw_no_bpf");
637 	ASSERT_EQ(buf[0], 1);
638 	ASSERT_EQ(buf[1], 47);
639 	ASSERT_EQ(buf[2], 0);
640 
641 	/* re-attach our program */
642 
643 	LOAD_PROGRAMS(progs);
644 
645 	/* inject one event */
646 	memset(buf, 0, sizeof(buf));
647 	buf[0] = 1;
648 	buf[1] = 42;
649 	uhid_send_event(_metadata, self->uhid_fd, buf, 6);
650 
651 	/* read the data from hidraw */
652 	memset(buf, 0, sizeof(buf));
653 	err = read(self->hidraw_fd, buf, sizeof(buf));
654 	ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
655 	ASSERT_EQ(buf[0], 1);
656 	ASSERT_EQ(buf[2], 47);
657 }
658 
659 /*
660  * Attach hid_change_report_id to the given uhid device,
661  * retrieve and open the matching hidraw node,
662  * inject one event in the uhid device,
663  * check that the program sees it and can change the data
664  */
665 TEST_F(hid_bpf, test_hid_change_report)
666 {
667 	const struct test_program progs[] = {
668 		{ .name = "hid_change_report_id" },
669 	};
670 	__u8 buf[10] = {0};
671 	int err;
672 
673 	LOAD_PROGRAMS(progs);
674 
675 	/* inject one event */
676 	buf[0] = 1;
677 	buf[1] = 42;
678 	uhid_send_event(_metadata, self->uhid_fd, buf, 6);
679 
680 	/* read the data from hidraw */
681 	memset(buf, 0, sizeof(buf));
682 	err = read(self->hidraw_fd, buf, sizeof(buf));
683 	ASSERT_EQ(err, 9) TH_LOG("read_hidraw");
684 	ASSERT_EQ(buf[0], 2);
685 	ASSERT_EQ(buf[1], 42);
686 	ASSERT_EQ(buf[2], 0) TH_LOG("leftovers_from_previous_test");
687 }
688 
689 static int libbpf_print_fn(enum libbpf_print_level level,
690 			   const char *format, va_list args)
691 {
692 	char buf[1024];
693 
694 	if (level == LIBBPF_DEBUG)
695 		return 0;
696 
697 	snprintf(buf, sizeof(buf), "# %s", format);
698 
699 	vfprintf(stdout, buf, args);
700 	return 0;
701 }
702 
703 static void __attribute__((constructor)) __constructor_order_last(void)
704 {
705 	if (!__constructor_order)
706 		__constructor_order = _CONSTRUCTOR_ORDER_BACKWARD;
707 }
708 
709 int main(int argc, char **argv)
710 {
711 	/* Use libbpf 1.0 API mode */
712 	libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
713 	libbpf_set_print(libbpf_print_fn);
714 
715 	return test_harness_run(argc, argv);
716 }
717