/libfido2/src/hid_linux.c
Line | Count | Source (jump to first uncovered line) |
1 | | /* |
2 | | * Copyright (c) 2019 Yubico AB. All rights reserved. |
3 | | * Use of this source code is governed by a BSD-style |
4 | | * license that can be found in the LICENSE file. |
5 | | */ |
6 | | |
7 | | #include <sys/types.h> |
8 | | |
9 | | #include <sys/ioctl.h> |
10 | | #include <linux/hidraw.h> |
11 | | #include <linux/input.h> |
12 | | |
13 | | #include <errno.h> |
14 | | #include <fcntl.h> |
15 | | #include <libudev.h> |
16 | | #include <poll.h> |
17 | | #include <string.h> |
18 | | #include <unistd.h> |
19 | | |
20 | | #include "fido.h" |
21 | | |
22 | | struct hid_linux { |
23 | | int fd; |
24 | | size_t report_in_len; |
25 | | size_t report_out_len; |
26 | | }; |
27 | | |
28 | | static int |
29 | | get_key_len(uint8_t tag, uint8_t *key, size_t *key_len) |
30 | 0 | { |
31 | 0 | *key = tag & 0xfc; |
32 | 0 | if ((*key & 0xf0) == 0xf0) { |
33 | 0 | fido_log_debug("%s: *key=0x%02x", __func__, *key); |
34 | 0 | return (-1); |
35 | 0 | } |
36 | 0 | |
37 | 0 | *key_len = tag & 0x3; |
38 | 0 | if (*key_len == 3) { |
39 | 0 | *key_len = 4; |
40 | 0 | } |
41 | 0 |
|
42 | 0 | return (0); |
43 | 0 | } |
44 | | |
45 | | static int |
46 | | get_key_val(const void *body, size_t key_len, uint32_t *val) |
47 | 0 | { |
48 | 0 | const uint8_t *ptr = body; |
49 | 0 |
|
50 | 0 | switch (key_len) { |
51 | 0 | case 0: |
52 | 0 | *val = 0; |
53 | 0 | break; |
54 | 0 | case 1: |
55 | 0 | *val = ptr[0]; |
56 | 0 | break; |
57 | 0 | case 2: |
58 | 0 | *val = (uint32_t)((ptr[1] << 8) | ptr[0]); |
59 | 0 | break; |
60 | 0 | default: |
61 | 0 | fido_log_debug("%s: key_len=%zu", __func__, key_len); |
62 | 0 | return (-1); |
63 | 0 | } |
64 | 0 | |
65 | 0 | return (0); |
66 | 0 | } |
67 | | |
68 | | static int |
69 | | get_usage_info(const struct hidraw_report_descriptor *hrd, uint32_t *usage_page, |
70 | | uint32_t *usage) |
71 | 0 | { |
72 | 0 | const uint8_t *ptr = hrd->value; |
73 | 0 | size_t len = hrd->size; |
74 | 0 |
|
75 | 0 | while (len > 0) { |
76 | 0 | const uint8_t tag = ptr[0]; |
77 | 0 | ptr++; |
78 | 0 | len--; |
79 | 0 |
|
80 | 0 | uint8_t key; |
81 | 0 | size_t key_len; |
82 | 0 | uint32_t key_val; |
83 | 0 |
|
84 | 0 | if (get_key_len(tag, &key, &key_len) < 0 || key_len > len || |
85 | 0 | get_key_val(ptr, key_len, &key_val) < 0) { |
86 | 0 | return (-1); |
87 | 0 | } |
88 | 0 | |
89 | 0 | if (key == 0x4) { |
90 | 0 | *usage_page = key_val; |
91 | 0 | } else if (key == 0x8) { |
92 | 0 | *usage = key_val; |
93 | 0 | } |
94 | 0 |
|
95 | 0 | ptr += key_len; |
96 | 0 | len -= key_len; |
97 | 0 | } |
98 | 0 |
|
99 | 0 | return (0); |
100 | 0 | } |
101 | | |
102 | | static int |
103 | | get_report_sizes(const struct hidraw_report_descriptor *hrd, |
104 | | size_t *report_in_len, size_t *report_out_len) |
105 | 0 | { |
106 | 0 | const uint8_t *ptr = hrd->value; |
107 | 0 | size_t len = hrd->size; |
108 | 0 | uint32_t report_size = 0; |
109 | 0 |
|
110 | 0 | while (len > 0) { |
111 | 0 | const uint8_t tag = ptr[0]; |
112 | 0 | ptr++; |
113 | 0 | len--; |
114 | 0 |
|
115 | 0 | uint8_t key; |
116 | 0 | size_t key_len; |
117 | 0 | uint32_t key_val; |
118 | 0 |
|
119 | 0 | if (get_key_len(tag, &key, &key_len) < 0 || key_len > len || |
120 | 0 | get_key_val(ptr, key_len, &key_val) < 0) { |
121 | 0 | return (-1); |
122 | 0 | } |
123 | 0 | |
124 | 0 | if (key == 0x94) { |
125 | 0 | report_size = key_val; |
126 | 0 | } else if (key == 0x80) { |
127 | 0 | *report_in_len = (size_t)report_size; |
128 | 0 | } else if (key == 0x90) { |
129 | 0 | *report_out_len = (size_t)report_size; |
130 | 0 | } |
131 | 0 |
|
132 | 0 | ptr += key_len; |
133 | 0 | len -= key_len; |
134 | 0 | } |
135 | 0 |
|
136 | 0 | return (0); |
137 | 0 | } |
138 | | |
139 | | static int |
140 | | get_report_descriptor(int fd, struct hidraw_report_descriptor *hrd) |
141 | 0 | { |
142 | 0 | int s = -1; |
143 | 0 |
|
144 | 0 | if (ioctl(fd, HIDIOCGRDESCSIZE, &s) < 0 || s < 0 || |
145 | 0 | (unsigned)s > HID_MAX_DESCRIPTOR_SIZE) { |
146 | 0 | fido_log_debug("%s: ioctl HIDIOCGRDESCSIZE", __func__); |
147 | 0 | return (-1); |
148 | 0 | } |
149 | 0 | |
150 | 0 | hrd->size = (unsigned)s; |
151 | 0 |
|
152 | 0 | if (ioctl(fd, HIDIOCGRDESC, hrd) < 0) { |
153 | 0 | fido_log_debug("%s: ioctl HIDIOCGRDESC", __func__); |
154 | 0 | return (-1); |
155 | 0 | } |
156 | 0 | |
157 | 0 | return (0); |
158 | 0 | } |
159 | | |
160 | | static bool |
161 | | is_fido(const char *path) |
162 | 0 | { |
163 | 0 | int fd; |
164 | 0 | uint32_t usage = 0; |
165 | 0 | uint32_t usage_page = 0; |
166 | 0 | struct hidraw_report_descriptor hrd; |
167 | 0 |
|
168 | 0 | memset(&hrd, 0, sizeof(hrd)); |
169 | 0 |
|
170 | 0 | if ((fd = open(path, O_RDONLY)) == -1) { |
171 | 0 | fido_log_debug("%s: open", __func__); |
172 | 0 | return (false); |
173 | 0 | } |
174 | 0 | |
175 | 0 | if (get_report_descriptor(fd, &hrd) < 0 || |
176 | 0 | get_usage_info(&hrd, &usage_page, &usage) < 0) { |
177 | 0 | close(fd); |
178 | 0 | return (false); |
179 | 0 | } |
180 | 0 | |
181 | 0 | close(fd); |
182 | 0 |
|
183 | 0 | return (usage_page == 0xf1d0); |
184 | 0 | } |
185 | | |
186 | | static int |
187 | | parse_uevent(const char *uevent, int *bus, int16_t *vendor_id, |
188 | | int16_t *product_id) |
189 | 0 | { |
190 | 0 | char *cp; |
191 | 0 | char *p; |
192 | 0 | char *s; |
193 | 0 | int ok = -1; |
194 | 0 | short unsigned int x; |
195 | 0 | short unsigned int y; |
196 | 0 | short unsigned int z; |
197 | 0 |
|
198 | 0 | if ((s = cp = strdup(uevent)) == NULL) |
199 | 0 | return (-1); |
200 | 0 | |
201 | 0 | while ((p = strsep(&cp, "\n")) != NULL && *p != '\0') { |
202 | 0 | if (strncmp(p, "HID_ID=", 7) == 0) { |
203 | 0 | if (sscanf(p + 7, "%hx:%hx:%hx", &x, &y, &z) == 3) { |
204 | 0 | *bus = (int)x; |
205 | 0 | *vendor_id = (int16_t)y; |
206 | 0 | *product_id = (int16_t)z; |
207 | 0 | ok = 0; |
208 | 0 | break; |
209 | 0 | } |
210 | 0 | } |
211 | 0 | } |
212 | 0 |
|
213 | 0 | free(s); |
214 | 0 |
|
215 | 0 | return (ok); |
216 | 0 | } |
217 | | |
218 | | static char * |
219 | | get_parent_attr(struct udev_device *dev, const char *subsystem, |
220 | | const char *devtype, const char *attr) |
221 | 0 | { |
222 | 0 | struct udev_device *parent; |
223 | 0 | const char *value; |
224 | 0 |
|
225 | 0 | if ((parent = udev_device_get_parent_with_subsystem_devtype(dev, |
226 | 0 | subsystem, devtype)) == NULL || (value = |
227 | 0 | udev_device_get_sysattr_value(parent, attr)) == NULL) |
228 | 0 | return (NULL); |
229 | 0 | |
230 | 0 | return (strdup(value)); |
231 | 0 | } |
232 | | |
233 | | static char * |
234 | | get_usb_attr(struct udev_device *dev, const char *attr) |
235 | 0 | { |
236 | 0 | return (get_parent_attr(dev, "usb", "usb_device", attr)); |
237 | 0 | } |
238 | | |
239 | | static int |
240 | | copy_info(fido_dev_info_t *di, struct udev *udev, |
241 | | struct udev_list_entry *udev_entry) |
242 | 0 | { |
243 | 0 | const char *name; |
244 | 0 | const char *path; |
245 | 0 | char *uevent = NULL; |
246 | 0 | struct udev_device *dev = NULL; |
247 | 0 | int bus = 0; |
248 | 0 | int ok = -1; |
249 | 0 |
|
250 | 0 | memset(di, 0, sizeof(*di)); |
251 | 0 |
|
252 | 0 | if ((name = udev_list_entry_get_name(udev_entry)) == NULL || |
253 | 0 | (dev = udev_device_new_from_syspath(udev, name)) == NULL || |
254 | 0 | (path = udev_device_get_devnode(dev)) == NULL || |
255 | 0 | is_fido(path) == 0) |
256 | 0 | goto fail; |
257 | 0 | |
258 | 0 | if ((uevent = get_parent_attr(dev, "hid", NULL, "uevent")) == NULL || |
259 | 0 | parse_uevent(uevent, &bus, &di->vendor_id, &di->product_id) < 0) { |
260 | 0 | fido_log_debug("%s: uevent", __func__); |
261 | 0 | goto fail; |
262 | 0 | } |
263 | 0 | |
264 | 0 | #ifndef FIDO_HID_ANY |
265 | 0 | if (bus != BUS_USB) { |
266 | 0 | fido_log_debug("%s: bus", __func__); |
267 | 0 | goto fail; |
268 | 0 | } |
269 | 0 | #endif |
270 | 0 | |
271 | 0 | di->path = strdup(path); |
272 | 0 | di->manufacturer = get_usb_attr(dev, "manufacturer"); |
273 | 0 | di->product = get_usb_attr(dev, "product"); |
274 | 0 |
|
275 | 0 | if (di->path == NULL || di->manufacturer == NULL || di->product == NULL) |
276 | 0 | goto fail; |
277 | 0 | |
278 | 0 | ok = 0; |
279 | 0 | fail: |
280 | 0 | if (dev != NULL) |
281 | 0 | udev_device_unref(dev); |
282 | 0 |
|
283 | 0 | free(uevent); |
284 | 0 |
|
285 | 0 | if (ok < 0) { |
286 | 0 | free(di->path); |
287 | 0 | free(di->manufacturer); |
288 | 0 | free(di->product); |
289 | 0 | explicit_bzero(di, sizeof(*di)); |
290 | 0 | } |
291 | 0 |
|
292 | 0 | return (ok); |
293 | 0 | } |
294 | | |
295 | | int |
296 | | fido_hid_manifest(fido_dev_info_t *devlist, size_t ilen, size_t *olen) |
297 | 0 | { |
298 | 0 | struct udev *udev = NULL; |
299 | 0 | struct udev_enumerate *udev_enum = NULL; |
300 | 0 | struct udev_list_entry *udev_list; |
301 | 0 | struct udev_list_entry *udev_entry; |
302 | 0 | int r = FIDO_ERR_INTERNAL; |
303 | 0 |
|
304 | 0 | *olen = 0; |
305 | 0 |
|
306 | 0 | if (ilen == 0) |
307 | 0 | return (FIDO_OK); /* nothing to do */ |
308 | 0 |
|
309 | 0 | if (devlist == NULL) |
310 | 0 | return (FIDO_ERR_INVALID_ARGUMENT); |
311 | 0 |
|
312 | 0 | if ((udev = udev_new()) == NULL || |
313 | 0 | (udev_enum = udev_enumerate_new(udev)) == NULL) |
314 | 0 | goto fail; |
315 | 0 | |
316 | 0 | if (udev_enumerate_add_match_subsystem(udev_enum, "hidraw") < 0 || |
317 | 0 | udev_enumerate_scan_devices(udev_enum) < 0) |
318 | 0 | goto fail; |
319 | 0 | |
320 | 0 | if ((udev_list = udev_enumerate_get_list_entry(udev_enum)) == NULL) { |
321 | 0 | r = FIDO_OK; /* zero hidraw devices */ |
322 | 0 | goto fail; |
323 | 0 | } |
324 | 0 |
|
325 | 0 | udev_list_entry_foreach(udev_entry, udev_list) { |
326 | 0 | if (copy_info(&devlist[*olen], udev, udev_entry) == 0) { |
327 | 0 | devlist[*olen].io = (fido_dev_io_t) { |
328 | 0 | fido_hid_open, |
329 | 0 | fido_hid_close, |
330 | 0 | fido_hid_read, |
331 | 0 | fido_hid_write, |
332 | 0 | }; |
333 | 0 | if (++(*olen) == ilen) |
334 | 0 | break; |
335 | 0 | } |
336 | 0 | } |
337 | 0 |
|
338 | 0 | r = FIDO_OK; |
339 | 0 | fail: |
340 | 0 | if (udev_enum != NULL) |
341 | 0 | udev_enumerate_unref(udev_enum); |
342 | 0 | if (udev != NULL) |
343 | 0 | udev_unref(udev); |
344 | 0 |
|
345 | 0 | return (r); |
346 | 0 | } |
347 | | |
348 | | void * |
349 | | fido_hid_open(const char *path) |
350 | 0 | { |
351 | 0 | struct hid_linux *ctx; |
352 | 0 | struct hidraw_report_descriptor hrd; |
353 | 0 |
|
354 | 0 | if ((ctx = calloc(1, sizeof(*ctx))) == NULL) |
355 | 0 | return (NULL); |
356 | 0 | |
357 | 0 | if ((ctx->fd = open(path, O_RDWR)) < 0) { |
358 | 0 | free(ctx); |
359 | 0 | return (NULL); |
360 | 0 | } |
361 | 0 | |
362 | 0 | if (get_report_descriptor(ctx->fd, &hrd) < 0 || get_report_sizes(&hrd, |
363 | 0 | &ctx->report_in_len, &ctx->report_out_len) < 0 || |
364 | 0 | ctx->report_in_len == 0 || ctx->report_out_len == 0) { |
365 | 0 | fido_log_debug("%s: using default report sizes", __func__); |
366 | 0 | ctx->report_in_len = CTAP_MAX_REPORT_LEN; |
367 | 0 | ctx->report_out_len = CTAP_MAX_REPORT_LEN; |
368 | 0 | } |
369 | 0 |
|
370 | 0 | return (ctx); |
371 | 0 | } |
372 | | |
373 | | void |
374 | | fido_hid_close(void *handle) |
375 | 0 | { |
376 | 0 | struct hid_linux *ctx = handle; |
377 | 0 |
|
378 | 0 | close(ctx->fd); |
379 | 0 | free(ctx); |
380 | 0 | } |
381 | | |
382 | | static int |
383 | | timespec_to_ms(const struct timespec *ts, int upper_bound) |
384 | 0 | { |
385 | 0 | int64_t x; |
386 | 0 | int64_t y; |
387 | 0 |
|
388 | 0 | if (ts->tv_sec < 0 || ts->tv_sec > INT64_MAX / 1000LL || |
389 | 0 | ts->tv_nsec < 0 || ts->tv_nsec / 1000000LL > INT64_MAX) |
390 | 0 | return (upper_bound); |
391 | 0 | |
392 | 0 | x = ts->tv_sec * 1000LL; |
393 | 0 | y = ts->tv_nsec / 1000000LL; |
394 | 0 |
|
395 | 0 | if (INT64_MAX - x < y || x + y > upper_bound) |
396 | 0 | return (upper_bound); |
397 | 0 | |
398 | 0 | return (int)(x + y); |
399 | 0 | } |
400 | | |
401 | | static int |
402 | | waitfd(int fd, int ms) |
403 | 0 | { |
404 | 0 | struct timespec ts_start; |
405 | 0 | struct timespec ts_now; |
406 | 0 | struct timespec ts_delta; |
407 | 0 | struct pollfd pfd; |
408 | 0 | int ms_remain; |
409 | 0 | int r; |
410 | 0 |
|
411 | 0 | if (ms < 0) |
412 | 0 | return (0); |
413 | 0 | |
414 | 0 | memset(&pfd, 0, sizeof(pfd)); |
415 | 0 | pfd.events = POLLIN; |
416 | 0 | pfd.fd = fd; |
417 | 0 |
|
418 | 0 | if (clock_gettime(CLOCK_MONOTONIC, &ts_start) != 0) { |
419 | 0 | fido_log_debug("%s: clock_gettime: %s", __func__, |
420 | 0 | strerror(errno)); |
421 | 0 | return (-1); |
422 | 0 | } |
423 | 0 | |
424 | 0 | for (ms_remain = ms; ms_remain > 0;) { |
425 | 0 | if ((r = poll(&pfd, 1, ms_remain)) > 0) |
426 | 0 | return (0); |
427 | 0 | else if (r == 0) |
428 | 0 | break; |
429 | 0 | else if (errno != EINTR) { |
430 | 0 | fido_log_debug("%s: poll: %s", __func__, |
431 | 0 | strerror(errno)); |
432 | 0 | return (-1); |
433 | 0 | } |
434 | 0 | /* poll interrupted - subtract time already waited */ |
435 | 0 | if (clock_gettime(CLOCK_MONOTONIC, &ts_now) != 0) { |
436 | 0 | fido_log_debug("%s: clock_gettime: %s", __func__, |
437 | 0 | strerror(errno)); |
438 | 0 | return (-1); |
439 | 0 | } |
440 | 0 | timespecsub(&ts_now, &ts_start, &ts_delta); |
441 | 0 | ms_remain = ms - timespec_to_ms(&ts_delta, ms); |
442 | 0 | } |
443 | 0 |
|
444 | 0 | return (-1); |
445 | 0 | } |
446 | | |
447 | | int |
448 | | fido_hid_read(void *handle, unsigned char *buf, size_t len, int ms) |
449 | 0 | { |
450 | 0 | struct hid_linux *ctx = handle; |
451 | 0 | ssize_t r; |
452 | 0 |
|
453 | 0 | if (len != ctx->report_in_len) { |
454 | 0 | fido_log_debug("%s: len %zu", __func__, len); |
455 | 0 | return (-1); |
456 | 0 | } |
457 | 0 | |
458 | 0 | if (waitfd(ctx->fd, ms) < 0) { |
459 | 0 | fido_log_debug("%s: fd not ready", __func__); |
460 | 0 | return (-1); |
461 | 0 | } |
462 | 0 | |
463 | 0 | if ((r = read(ctx->fd, buf, len)) < 0 || (size_t)r != len) { |
464 | 0 | fido_log_debug("%s: read", __func__); |
465 | 0 | return (-1); |
466 | 0 | } |
467 | 0 | |
468 | 0 | return ((int)r); |
469 | 0 | } |
470 | | |
471 | | int |
472 | | fido_hid_write(void *handle, const unsigned char *buf, size_t len) |
473 | 0 | { |
474 | 0 | struct hid_linux *ctx = handle; |
475 | 0 | ssize_t r; |
476 | 0 |
|
477 | 0 | if (len != ctx->report_out_len + 1) { |
478 | 0 | fido_log_debug("%s: len %zu", __func__, len); |
479 | 0 | return (-1); |
480 | 0 | } |
481 | 0 | |
482 | 0 | if ((r = write(ctx->fd, buf, len)) < 0 || (size_t)r != len) { |
483 | 0 | fido_log_debug("%s: write", __func__); |
484 | 0 | return (-1); |
485 | 0 | } |
486 | 0 | |
487 | 0 | return ((int)r); |
488 | 0 | } |
489 | | |
490 | | size_t |
491 | | fido_hid_report_in_len(void *handle) |
492 | 0 | { |
493 | 0 | struct hid_linux *ctx = handle; |
494 | 0 |
|
495 | 0 | return (ctx->report_in_len); |
496 | 0 | } |
497 | | |
498 | | size_t |
499 | | fido_hid_report_out_len(void *handle) |
500 | 0 | { |
501 | 0 | struct hid_linux *ctx = handle; |
502 | 0 |
|
503 | 0 | return (ctx->report_out_len); |
504 | 0 | } |