1
/* SPDX-License-Identifier: GPL-2.0 */
2
/* Copyright (c) 2022-2024 Red Hat */
3

4
#include "../kselftest_harness.h"
5

6
#include <fcntl.h>
7
#include <fnmatch.h>
8
#include <dirent.h>
9
#include <poll.h>
10
#include <pthread.h>
11
#include <stdbool.h>
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#include <linux/hidraw.h>
13
#include <linux/uhid.h>
14

15
#define SHOW_UHID_DEBUG 0
16

17
#define min(a, b) \
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	({ __typeof__(a) _a = (a); \
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	__typeof__(b) _b = (b); \
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	_a < _b ? _a : _b; })
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22
struct uhid_device {
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	int dev_id;		/* uniq (random) number to identify the device */
24
	int uhid_fd;
25
	int hid_id;		/* HID device id in the system */
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	__u16 bus;
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	__u32 vid;
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	__u32 pid;
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	pthread_t tid;		/* thread for reading uhid events */
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};
31

32
static unsigned char rdesc[] = {
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	0x06, 0x00, 0xff,	/* Usage Page (Vendor Defined Page 1) */
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	0x09, 0x21,		/* Usage (Vendor Usage 0x21) */
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	0xa1, 0x01,		/* COLLECTION (Application) */
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	0x09, 0x01,			/* Usage (Vendor Usage 0x01) */
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	0xa1, 0x00,			/* COLLECTION (Physical) */
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	0x85, 0x02,				/* REPORT_ID (2) */
39
	0x19, 0x01,				/* USAGE_MINIMUM (1) */
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	0x29, 0x08,				/* USAGE_MAXIMUM (3) */
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	0x15, 0x00,				/* LOGICAL_MINIMUM (0) */
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	0x25, 0xff,				/* LOGICAL_MAXIMUM (255) */
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	0x95, 0x08,				/* REPORT_COUNT (8) */
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	0x75, 0x08,				/* REPORT_SIZE (8) */
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	0x81, 0x02,				/* INPUT (Data,Var,Abs) */
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	0xc0,				/* END_COLLECTION */
47
	0x09, 0x01,			/* Usage (Vendor Usage 0x01) */
48
	0xa1, 0x00,			/* COLLECTION (Physical) */
49
	0x85, 0x01,				/* REPORT_ID (1) */
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	0x06, 0x00, 0xff,			/* Usage Page (Vendor Defined Page 1) */
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	0x19, 0x01,				/* USAGE_MINIMUM (1) */
52
	0x29, 0x03,				/* USAGE_MAXIMUM (3) */
53
	0x15, 0x00,				/* LOGICAL_MINIMUM (0) */
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	0x25, 0x01,				/* LOGICAL_MAXIMUM (1) */
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	0x95, 0x03,				/* REPORT_COUNT (3) */
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	0x75, 0x01,				/* REPORT_SIZE (1) */
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	0x81, 0x02,				/* INPUT (Data,Var,Abs) */
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	0x95, 0x01,				/* REPORT_COUNT (1) */
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	0x75, 0x05,				/* REPORT_SIZE (5) */
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	0x81, 0x01,				/* INPUT (Cnst,Var,Abs) */
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	0x05, 0x01,				/* USAGE_PAGE (Generic Desktop) */
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	0x09, 0x30,				/* USAGE (X) */
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	0x09, 0x31,				/* USAGE (Y) */
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	0x15, 0x81,				/* LOGICAL_MINIMUM (-127) */
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	0x25, 0x7f,				/* LOGICAL_MAXIMUM (127) */
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	0x75, 0x10,				/* REPORT_SIZE (16) */
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	0x95, 0x02,				/* REPORT_COUNT (2) */
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	0x81, 0x06,				/* INPUT (Data,Var,Rel) */
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70
	0x06, 0x00, 0xff,			/* Usage Page (Vendor Defined Page 1) */
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	0x19, 0x01,				/* USAGE_MINIMUM (1) */
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	0x29, 0x03,				/* USAGE_MAXIMUM (3) */
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	0x15, 0x00,				/* LOGICAL_MINIMUM (0) */
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	0x25, 0x01,				/* LOGICAL_MAXIMUM (1) */
75
	0x95, 0x03,				/* REPORT_COUNT (3) */
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	0x75, 0x01,				/* REPORT_SIZE (1) */
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	0x91, 0x02,				/* Output (Data,Var,Abs) */
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	0x95, 0x01,				/* REPORT_COUNT (1) */
79
	0x75, 0x05,				/* REPORT_SIZE (5) */
80
	0x91, 0x01,				/* Output (Cnst,Var,Abs) */
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82
	0x06, 0x00, 0xff,			/* Usage Page (Vendor Defined Page 1) */
83
	0x19, 0x06,				/* USAGE_MINIMUM (6) */
84
	0x29, 0x08,				/* USAGE_MAXIMUM (8) */
85
	0x15, 0x00,				/* LOGICAL_MINIMUM (0) */
86
	0x25, 0x01,				/* LOGICAL_MAXIMUM (1) */
87
	0x95, 0x03,				/* REPORT_COUNT (3) */
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	0x75, 0x01,				/* REPORT_SIZE (1) */
89
	0xb1, 0x02,				/* Feature (Data,Var,Abs) */
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	0x95, 0x01,				/* REPORT_COUNT (1) */
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	0x75, 0x05,				/* REPORT_SIZE (5) */
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	0x91, 0x01,				/* Output (Cnst,Var,Abs) */
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	0xc0,				/* END_COLLECTION */
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	0xc0,			/* END_COLLECTION */
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};
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98
static __u8 feature_data[] = { 1, 2 };
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100
#define ASSERT_OK(data) ASSERT_FALSE(data)
101
#define ASSERT_OK_PTR(ptr) ASSERT_NE(NULL, ptr)
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103
#define UHID_LOG(fmt, ...) do { \
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	if (SHOW_UHID_DEBUG) \
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		TH_LOG(fmt, ##__VA_ARGS__); \
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} while (0)
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108
static pthread_mutex_t uhid_started_mtx = PTHREAD_MUTEX_INITIALIZER;
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static pthread_cond_t uhid_started = PTHREAD_COND_INITIALIZER;
110

111
static pthread_mutex_t uhid_output_mtx = PTHREAD_MUTEX_INITIALIZER;
112
static pthread_cond_t uhid_output_cond = PTHREAD_COND_INITIALIZER;
113
static unsigned char output_report[10];
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115
/* no need to protect uhid_stopped, only one thread accesses it */
116
static bool uhid_stopped;
117

118
static int uhid_write(struct __test_metadata *_metadata, int fd, const struct uhid_event *ev)
119
{
120
	ssize_t ret;
121

122
	ret = write(fd, ev, sizeof(*ev));
123
	if (ret < 0) {
124
		TH_LOG("Cannot write to uhid: %m");
125
		return -errno;
126
	} else if (ret != sizeof(*ev)) {
127
		TH_LOG("Wrong size written to uhid: %zd != %zu",
128
			ret, sizeof(ev));
129
		return -EFAULT;
130
	} else {
131
		return 0;
132
	}
133
}
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135
static int uhid_create(struct __test_metadata *_metadata, int fd, int rand_nb,
136
		       __u16 bus, __u32 vid, __u32 pid, __u8 *rdesc,
137
		       size_t rdesc_size)
138
{
139
	struct uhid_event ev;
140
	char buf[25];
141

142
	sprintf(buf, "test-uhid-device-%d", rand_nb);
143

144
	memset(&ev, 0, sizeof(ev));
145
	ev.type = UHID_CREATE;
146
	strcpy((char *)ev.u.create.name, buf);
147
	ev.u.create.rd_data = rdesc;
148
	ev.u.create.rd_size = rdesc_size;
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	ev.u.create.bus = bus;
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	ev.u.create.vendor = vid;
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	ev.u.create.product = pid;
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	ev.u.create.version = 0;
153
	ev.u.create.country = 0;
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155
	sprintf(buf, "%d", rand_nb);
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	strcpy((char *)ev.u.create.phys, buf);
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158
	return uhid_write(_metadata, fd, &ev);
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}
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161
static void uhid_destroy(struct __test_metadata *_metadata, struct uhid_device *hid)
162
{
163
	struct uhid_event ev;
164

165
	memset(&ev, 0, sizeof(ev));
166
	ev.type = UHID_DESTROY;
167

168
	uhid_write(_metadata, hid->uhid_fd, &ev);
169
}
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171
static int uhid_event(struct __test_metadata *_metadata, int fd)
172
{
173
	struct uhid_event ev, answer;
174
	ssize_t ret;
175

176
	memset(&ev, 0, sizeof(ev));
177
	ret = read(fd, &ev, sizeof(ev));
178
	if (ret == 0) {
179
		UHID_LOG("Read HUP on uhid-cdev");
180
		return -EFAULT;
181
	} else if (ret < 0) {
182
		UHID_LOG("Cannot read uhid-cdev: %m");
183
		return -errno;
184
	} else if (ret != sizeof(ev)) {
185
		UHID_LOG("Invalid size read from uhid-dev: %zd != %zu",
186
			ret, sizeof(ev));
187
		return -EFAULT;
188
	}
189

190
	switch (ev.type) {
191
	case UHID_START:
192
		pthread_mutex_lock(&uhid_started_mtx);
193
		pthread_cond_signal(&uhid_started);
194
		pthread_mutex_unlock(&uhid_started_mtx);
195

196
		UHID_LOG("UHID_START from uhid-dev");
197
		break;
198
	case UHID_STOP:
199
		uhid_stopped = true;
200

201
		UHID_LOG("UHID_STOP from uhid-dev");
202
		break;
203
	case UHID_OPEN:
204
		UHID_LOG("UHID_OPEN from uhid-dev");
205
		break;
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	case UHID_CLOSE:
207
		UHID_LOG("UHID_CLOSE from uhid-dev");
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		break;
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	case UHID_OUTPUT:
210
		UHID_LOG("UHID_OUTPUT from uhid-dev");
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212
		pthread_mutex_lock(&uhid_output_mtx);
213
		memcpy(output_report,
214
		       ev.u.output.data,
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		       min(ev.u.output.size, sizeof(output_report)));
216
		pthread_cond_signal(&uhid_output_cond);
217
		pthread_mutex_unlock(&uhid_output_mtx);
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		break;
219
	case UHID_GET_REPORT:
220
		UHID_LOG("UHID_GET_REPORT from uhid-dev");
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222
		answer.type = UHID_GET_REPORT_REPLY;
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		answer.u.get_report_reply.id = ev.u.get_report.id;
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		answer.u.get_report_reply.err = ev.u.get_report.rnum == 1 ? 0 : -EIO;
225
		answer.u.get_report_reply.size = sizeof(feature_data);
226
		memcpy(answer.u.get_report_reply.data, feature_data, sizeof(feature_data));
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228
		uhid_write(_metadata, fd, &answer);
229

230
		break;
231
	case UHID_SET_REPORT:
232
		UHID_LOG("UHID_SET_REPORT from uhid-dev");
233

234
		answer.type = UHID_SET_REPORT_REPLY;
235
		answer.u.set_report_reply.id = ev.u.set_report.id;
236
		answer.u.set_report_reply.err = 0; /* success */
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238
		uhid_write(_metadata, fd, &answer);
239
		break;
240
	default:
241
		TH_LOG("Invalid event from uhid-dev: %u", ev.type);
242
	}
243

244
	return 0;
245
}
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247
struct uhid_thread_args {
248
	int fd;
249
	struct __test_metadata *_metadata;
250
};
251
static void *uhid_read_events_thread(void *arg)
252
{
253
	struct uhid_thread_args *args = (struct uhid_thread_args *)arg;
254
	struct __test_metadata *_metadata = args->_metadata;
255
	struct pollfd pfds[1];
256
	int fd = args->fd;
257
	int ret = 0;
258

259
	pfds[0].fd = fd;
260
	pfds[0].events = POLLIN;
261

262
	uhid_stopped = false;
263

264
	while (!uhid_stopped) {
265
		ret = poll(pfds, 1, 100);
266
		if (ret < 0) {
267
			TH_LOG("Cannot poll for fds: %m");
268
			break;
269
		}
270
		if (pfds[0].revents & POLLIN) {
271
			ret = uhid_event(_metadata, fd);
272
			if (ret)
273
				break;
274
		}
275
	}
276

277
	return (void *)(long)ret;
278
}
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280
static int uhid_start_listener(struct __test_metadata *_metadata, pthread_t *tid, int uhid_fd)
281
{
282
	struct uhid_thread_args args = {
283
		.fd = uhid_fd,
284
		._metadata = _metadata,
285
	};
286
	int err;
287

288
	pthread_mutex_lock(&uhid_started_mtx);
289
	err = pthread_create(tid, NULL, uhid_read_events_thread, (void *)&args);
290
	ASSERT_EQ(0, err) {
291
		TH_LOG("Could not start the uhid thread: %d", err);
292
		pthread_mutex_unlock(&uhid_started_mtx);
293
		close(uhid_fd);
294
		return -EIO;
295
	}
296
	pthread_cond_wait(&uhid_started, &uhid_started_mtx);
297
	pthread_mutex_unlock(&uhid_started_mtx);
298

299
	return 0;
300
}
301

302
static int uhid_send_event(struct __test_metadata *_metadata, struct uhid_device *hid,
303
			   __u8 *buf, size_t size)
304
{
305
	struct uhid_event ev;
306

307
	if (size > sizeof(ev.u.input.data))
308
		return -E2BIG;
309

310
	memset(&ev, 0, sizeof(ev));
311
	ev.type = UHID_INPUT2;
312
	ev.u.input2.size = size;
313

314
	memcpy(ev.u.input2.data, buf, size);
315

316
	return uhid_write(_metadata, hid->uhid_fd, &ev);
317
}
318

319
static bool match_sysfs_device(struct uhid_device *hid, const char *workdir, struct dirent *dir)
320
{
321
	char target[20] = "";
322
	char phys[512];
323
	char uevent[1024];
324
	char temp[512];
325
	int fd, nread;
326
	bool found = false;
327

328
	snprintf(target, sizeof(target), "%04X:%04X:%04X.*", hid->bus, hid->vid, hid->pid);
329

330
	if (fnmatch(target, dir->d_name, 0))
331
		return false;
332

333
	/* we found the correct VID/PID, now check for phys */
334
	sprintf(uevent, "%s/%s/uevent", workdir, dir->d_name);
335

336
	fd = open(uevent, O_RDONLY | O_NONBLOCK);
337
	if (fd < 0)
338
		return false;
339

340
	sprintf(phys, "PHYS=%d", hid->dev_id);
341

342
	nread = read(fd, temp, ARRAY_SIZE(temp));
343
	if (nread > 0 && (strstr(temp, phys)) != NULL)
344
		found = true;
345

346
	close(fd);
347

348
	return found;
349
}
350

351
static int get_hid_id(struct uhid_device *hid)
352
{
353
	const char *workdir = "/sys/devices/virtual/misc/uhid";
354
	const char *str_id;
355
	DIR *d;
356
	struct dirent *dir;
357
	int found = -1, attempts = 3;
358

359
	/* it would be nice to be able to use nftw, but the no_alu32 target doesn't support it */
360

361
	while (found < 0 && attempts > 0) {
362
		attempts--;
363
		d = opendir(workdir);
364
		if (d) {
365
			while ((dir = readdir(d)) != NULL) {
366
				if (!match_sysfs_device(hid, workdir, dir))
367
					continue;
368

369
				str_id = dir->d_name + sizeof("0000:0000:0000.");
370
				found = (int)strtol(str_id, NULL, 16);
371

372
				break;
373
			}
374
			closedir(d);
375
		}
376
		if (found < 0)
377
			usleep(100000);
378
	}
379

380
	return found;
381
}
382

383
static int get_hidraw(struct uhid_device *hid)
384
{
385
	const char *workdir = "/sys/devices/virtual/misc/uhid";
386
	char sysfs[1024];
387
	DIR *d, *subd;
388
	struct dirent *dir, *subdir;
389
	int i, found = -1;
390

391
	/* retry 5 times in case the system is loaded */
392
	for (i = 5; i > 0; i--) {
393
		usleep(10);
394
		d = opendir(workdir);
395

396
		if (!d)
397
			continue;
398

399
		while ((dir = readdir(d)) != NULL) {
400
			if (!match_sysfs_device(hid, workdir, dir))
401
				continue;
402

403
			sprintf(sysfs, "%s/%s/hidraw", workdir, dir->d_name);
404

405
			subd = opendir(sysfs);
406
			if (!subd)
407
				continue;
408

409
			while ((subdir = readdir(subd)) != NULL) {
410
				if (fnmatch("hidraw*", subdir->d_name, 0))
411
					continue;
412

413
				found = atoi(subdir->d_name + strlen("hidraw"));
414
			}
415

416
			closedir(subd);
417

418
			if (found > 0)
419
				break;
420
		}
421
		closedir(d);
422
	}
423

424
	return found;
425
}
426

427
static int open_hidraw(struct uhid_device *hid)
428
{
429
	int hidraw_number;
430
	char hidraw_path[64] = { 0 };
431

432
	hidraw_number = get_hidraw(hid);
433
	if (hidraw_number < 0)
434
		return hidraw_number;
435

436
	/* open hidraw node to check the other side of the pipe */
437
	sprintf(hidraw_path, "/dev/hidraw%d", hidraw_number);
438
	return open(hidraw_path, O_RDWR | O_NONBLOCK);
439
}
440

441
static int setup_uhid(struct __test_metadata *_metadata, struct uhid_device *hid,
442
		      __u16 bus, __u32 vid, __u32 pid, const __u8 *rdesc, size_t rdesc_size)
443
{
444
	const char *path = "/dev/uhid";
445
	time_t t;
446
	int ret;
447

448
	/* initialize random number generator */
449
	srand((unsigned int)time(&t));
450

451
	hid->dev_id = rand() % 1024;
452
	hid->bus = bus;
453
	hid->vid = vid;
454
	hid->pid = pid;
455

456
	hid->uhid_fd = open(path, O_RDWR | O_CLOEXEC);
457
	ASSERT_GE(hid->uhid_fd, 0) TH_LOG("open uhid-cdev failed; %d", hid->uhid_fd);
458

459
	ret = uhid_create(_metadata, hid->uhid_fd, hid->dev_id, bus, vid, pid,
460
			  (__u8 *)rdesc, rdesc_size);
461
	ASSERT_EQ(0, ret) {
462
		TH_LOG("create uhid device failed: %d", ret);
463
		close(hid->uhid_fd);
464
		return ret;
465
	}
466

467
	/* locate the uevent file of the created device */
468
	hid->hid_id = get_hid_id(hid);
469
	ASSERT_GT(hid->hid_id, 0)
470
		TH_LOG("Could not locate uhid device id: %d", hid->hid_id);
471

472
	ret = uhid_start_listener(_metadata, &hid->tid, hid->uhid_fd);
473
	ASSERT_EQ(0, ret) {
474
		TH_LOG("could not start udev listener: %d", ret);
475
		close(hid->uhid_fd);
476
		return ret;
477
	}
478

479
	return 0;
480
}
481

482