1 /* $NetBSD: parse.c,v 1.11 2000/09/24 02:19:54 augustss Exp $ */
2
3 /*-
4 * SPDX-License-Identifier: BSD-2-Clause
5 *
6 * Copyright (c) 1999, 2001 Lennart Augustsson <augustss@netbsd.org>
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <sys/cdefs.h>
32 #include <assert.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <sys/time.h>
36
37 #include <dev/usb/usb.h>
38 #include <dev/usb/usbhid.h>
39
40 #include "usbhid.h"
41 #include "usbvar.h"
42
43 #define MAXUSAGE 100
44 #define MAXPUSH 4
45 #define MAXID 64
46 #define ITEMTYPES 3
47
48 struct hid_pos_data {
49 int32_t rid;
50 uint32_t pos[ITEMTYPES];
51 };
52
53 struct hid_data {
54 const uint8_t *start;
55 const uint8_t *end;
56 const uint8_t *p;
57 struct hid_item cur[MAXPUSH];
58 struct hid_pos_data last_pos[MAXID];
59 uint32_t pos[ITEMTYPES];
60 int32_t usages_min[MAXUSAGE];
61 int32_t usages_max[MAXUSAGE];
62 int32_t usage_last; /* last seen usage */
63 uint32_t loc_size; /* last seen size */
64 uint32_t loc_count; /* last seen count */
65 uint8_t kindset; /* we have 5 kinds so 8 bits are enough */
66 uint8_t pushlevel; /* current pushlevel */
67 uint8_t ncount; /* end usage item count */
68 uint8_t icount; /* current usage item count */
69 uint8_t nusage; /* end "usages_min/max" index */
70 uint8_t iusage; /* current "usages_min/max" index */
71 uint8_t ousage; /* current "usages_min/max" offset */
72 uint8_t susage; /* usage set flags */
73 int32_t reportid; /* requested report ID */
74 };
75
76 /*------------------------------------------------------------------------*
77 * hid_clear_local
78 *------------------------------------------------------------------------*/
79 static void
hid_clear_local(hid_item_t * c)80 hid_clear_local(hid_item_t *c)
81 {
82
83 c->usage = 0;
84 c->usage_minimum = 0;
85 c->usage_maximum = 0;
86 c->designator_index = 0;
87 c->designator_minimum = 0;
88 c->designator_maximum = 0;
89 c->string_index = 0;
90 c->string_minimum = 0;
91 c->string_maximum = 0;
92 c->set_delimiter = 0;
93 }
94
95 static void
hid_switch_rid(struct hid_data * s,struct hid_item * c,int32_t next_rID)96 hid_switch_rid(struct hid_data *s, struct hid_item *c, int32_t next_rID)
97 {
98 uint8_t i, j;
99
100 /* check for same report ID - optimise */
101
102 if (c->report_ID == next_rID)
103 return;
104
105 /* save current position for current rID */
106
107 if (c->report_ID == 0) {
108 i = 0;
109 } else {
110 for (i = 1; i != MAXID; i++) {
111 if (s->last_pos[i].rid == c->report_ID)
112 break;
113 if (s->last_pos[i].rid == 0)
114 break;
115 }
116 }
117 if (i != MAXID) {
118 s->last_pos[i].rid = c->report_ID;
119 for (j = 0; j < ITEMTYPES; j++)
120 s->last_pos[i].pos[j] = s->pos[j];
121 }
122
123 /* store next report ID */
124
125 c->report_ID = next_rID;
126
127 /* lookup last position for next rID */
128
129 if (next_rID == 0) {
130 i = 0;
131 } else {
132 for (i = 1; i != MAXID; i++) {
133 if (s->last_pos[i].rid == next_rID)
134 break;
135 if (s->last_pos[i].rid == 0)
136 break;
137 }
138 }
139 if (i != MAXID) {
140 s->last_pos[i].rid = next_rID;
141 for (j = 0; j < ITEMTYPES; j++)
142 s->pos[j] = s->last_pos[i].pos[j];
143 } else {
144 for (j = 0; j < ITEMTYPES; j++)
145 s->pos[j] = 0; /* Out of RID entries. */
146 }
147 }
148
149 /*------------------------------------------------------------------------*
150 * hid_start_parse
151 *------------------------------------------------------------------------*/
152 hid_data_t
hid_start_parse(report_desc_t d,int kindset,int id)153 hid_start_parse(report_desc_t d, int kindset, int id)
154 {
155 struct hid_data *s;
156
157 s = malloc(sizeof *s);
158 memset(s, 0, sizeof *s);
159 s->start = s->p = d->data;
160 s->end = d->data + d->size;
161 s->kindset = kindset;
162 s->reportid = id;
163 return (s);
164 }
165
166 /*------------------------------------------------------------------------*
167 * hid_end_parse
168 *------------------------------------------------------------------------*/
169 void
hid_end_parse(hid_data_t s)170 hid_end_parse(hid_data_t s)
171 {
172
173 if (s == NULL)
174 return;
175
176 free(s);
177 }
178
179 /*------------------------------------------------------------------------*
180 * get byte from HID descriptor
181 *------------------------------------------------------------------------*/
182 static uint8_t
hid_get_byte(struct hid_data * s,const uint16_t wSize)183 hid_get_byte(struct hid_data *s, const uint16_t wSize)
184 {
185 const uint8_t *ptr;
186 uint8_t retval;
187
188 ptr = s->p;
189
190 /* check if end is reached */
191 if (ptr == s->end)
192 return (0);
193
194 /* read out a byte */
195 retval = *ptr;
196
197 /* check if data pointer can be advanced by "wSize" bytes */
198 if ((s->end - ptr) < wSize)
199 ptr = s->end;
200 else
201 ptr += wSize;
202
203 /* update pointer */
204 s->p = ptr;
205
206 return (retval);
207 }
208
209 /*------------------------------------------------------------------------*
210 * hid_get_item
211 *------------------------------------------------------------------------*/
212 static int
hid_get_item_raw(hid_data_t s,hid_item_t * h)213 hid_get_item_raw(hid_data_t s, hid_item_t *h)
214 {
215 hid_item_t *c;
216 unsigned int bTag, bType, bSize;
217 int32_t mask;
218 int32_t dval;
219
220 if (s == NULL)
221 return (0);
222
223 c = &s->cur[s->pushlevel];
224
225 top:
226 /* check if there is an array of items */
227 if (s->icount < s->ncount) {
228 /* get current usage */
229 if (s->iusage < s->nusage) {
230 dval = s->usages_min[s->iusage] + s->ousage;
231 c->usage = dval;
232 s->usage_last = dval;
233 if (dval == s->usages_max[s->iusage]) {
234 s->iusage ++;
235 s->ousage = 0;
236 } else {
237 s->ousage ++;
238 }
239 } else {
240 /* Using last usage */
241 dval = s->usage_last;
242 }
243 s->icount ++;
244 /*
245 * Only copy HID item, increment position and return
246 * if correct kindset!
247 */
248 if (s->kindset & (1 << c->kind)) {
249 *h = *c;
250 h->pos = s->pos[c->kind];
251 s->pos[c->kind] += c->report_size * c->report_count;
252 return (1);
253 }
254 }
255
256 /* reset state variables */
257 s->icount = 0;
258 s->ncount = 0;
259 s->iusage = 0;
260 s->nusage = 0;
261 s->susage = 0;
262 s->ousage = 0;
263 hid_clear_local(c);
264
265 /* get next item */
266 while (s->p != s->end) {
267
268 bSize = hid_get_byte(s, 1);
269 if (bSize == 0xfe) {
270 /* long item */
271 bSize = hid_get_byte(s, 1);
272 bSize |= hid_get_byte(s, 1) << 8;
273 bTag = hid_get_byte(s, 1);
274 bType = 0xff; /* XXX what should it be */
275 } else {
276 /* short item */
277 bTag = bSize >> 4;
278 bType = (bSize >> 2) & 3;
279 bSize &= 3;
280 if (bSize == 3)
281 bSize = 4;
282 }
283
284 switch(bSize) {
285 case 0:
286 dval = 0;
287 mask = 0;
288 break;
289 case 1:
290 dval = (int8_t)hid_get_byte(s, 1);
291 mask = 0xFF;
292 break;
293 case 2:
294 dval = hid_get_byte(s, 1);
295 dval |= hid_get_byte(s, 1) << 8;
296 dval = (int16_t)dval;
297 mask = 0xFFFF;
298 break;
299 case 4:
300 dval = hid_get_byte(s, 1);
301 dval |= hid_get_byte(s, 1) << 8;
302 dval |= hid_get_byte(s, 1) << 16;
303 dval |= hid_get_byte(s, 1) << 24;
304 mask = 0xFFFFFFFF;
305 break;
306 default:
307 dval = hid_get_byte(s, bSize);
308 continue;
309 }
310
311 switch (bType) {
312 case 0: /* Main */
313 switch (bTag) {
314 case 8: /* Input */
315 c->kind = hid_input;
316 c->flags = dval;
317 ret:
318 c->report_count = s->loc_count;
319 c->report_size = s->loc_size;
320
321 if (c->flags & HIO_VARIABLE) {
322 /* range check usage count */
323 if (c->report_count > 255) {
324 s->ncount = 255;
325 } else
326 s->ncount = c->report_count;
327
328 /*
329 * The "top" loop will return
330 * one and one item:
331 */
332 c->report_count = 1;
333 c->usage_minimum = 0;
334 c->usage_maximum = 0;
335 } else {
336 s->ncount = 1;
337 }
338 goto top;
339
340 case 9: /* Output */
341 c->kind = hid_output;
342 c->flags = dval;
343 goto ret;
344 case 10: /* Collection */
345 c->kind = hid_collection;
346 c->collection = dval;
347 c->collevel++;
348 c->usage = s->usage_last;
349 *h = *c;
350 return (1);
351 case 11: /* Feature */
352 c->kind = hid_feature;
353 c->flags = dval;
354 goto ret;
355 case 12: /* End collection */
356 c->kind = hid_endcollection;
357 if (c->collevel == 0) {
358 /* Invalid end collection. */
359 return (0);
360 }
361 c->collevel--;
362 *h = *c;
363 return (1);
364 default:
365 break;
366 }
367 break;
368
369 case 1: /* Global */
370 switch (bTag) {
371 case 0:
372 c->_usage_page = dval << 16;
373 break;
374 case 1:
375 c->logical_minimum = dval;
376 break;
377 case 2:
378 c->logical_maximum = dval;
379 break;
380 case 3:
381 c->physical_minimum = dval;
382 break;
383 case 4:
384 c->physical_maximum = dval;
385 break;
386 case 5:
387 c->unit_exponent = dval;
388 break;
389 case 6:
390 c->unit = dval;
391 break;
392 case 7:
393 /* mask because value is unsigned */
394 s->loc_size = dval & mask;
395 break;
396 case 8:
397 hid_switch_rid(s, c, dval & mask);
398 break;
399 case 9:
400 /* mask because value is unsigned */
401 s->loc_count = dval & mask;
402 break;
403 case 10: /* Push */
404 /* stop parsing, if invalid push level */
405 if ((s->pushlevel + 1) >= MAXPUSH)
406 return (0);
407 s->pushlevel ++;
408 s->cur[s->pushlevel] = *c;
409 /* store size and count */
410 c->report_size = s->loc_size;
411 c->report_count = s->loc_count;
412 /* update current item pointer */
413 c = &s->cur[s->pushlevel];
414 break;
415 case 11: /* Pop */
416 /* stop parsing, if invalid push level */
417 if (s->pushlevel == 0)
418 return (0);
419 s->pushlevel --;
420 c = &s->cur[s->pushlevel];
421 /* restore size and count */
422 s->loc_size = c->report_size;
423 s->loc_count = c->report_count;
424 c->report_size = 0;
425 c->report_count = 0;
426 break;
427 default:
428 break;
429 }
430 break;
431 case 2: /* Local */
432 switch (bTag) {
433 case 0:
434 if (bSize != 4)
435 dval = (dval & mask) | c->_usage_page;
436
437 /* set last usage, in case of a collection */
438 s->usage_last = dval;
439
440 if (s->nusage < MAXUSAGE) {
441 s->usages_min[s->nusage] = dval;
442 s->usages_max[s->nusage] = dval;
443 s->nusage ++;
444 }
445 /* else XXX */
446
447 /* clear any pending usage sets */
448 s->susage = 0;
449 break;
450 case 1:
451 s->susage |= 1;
452
453 if (bSize != 4)
454 dval = (dval & mask) | c->_usage_page;
455 c->usage_minimum = dval;
456
457 goto check_set;
458 case 2:
459 s->susage |= 2;
460
461 if (bSize != 4)
462 dval = (dval & mask) | c->_usage_page;
463 c->usage_maximum = dval;
464
465 check_set:
466 if (s->susage != 3)
467 break;
468
469 /* sanity check */
470 if ((s->nusage < MAXUSAGE) &&
471 (c->usage_minimum <= c->usage_maximum)) {
472 /* add usage range */
473 s->usages_min[s->nusage] =
474 c->usage_minimum;
475 s->usages_max[s->nusage] =
476 c->usage_maximum;
477 s->nusage ++;
478 }
479 /* else XXX */
480
481 s->susage = 0;
482 break;
483 case 3:
484 c->designator_index = dval;
485 break;
486 case 4:
487 c->designator_minimum = dval;
488 break;
489 case 5:
490 c->designator_maximum = dval;
491 break;
492 case 7:
493 c->string_index = dval;
494 break;
495 case 8:
496 c->string_minimum = dval;
497 break;
498 case 9:
499 c->string_maximum = dval;
500 break;
501 case 10:
502 c->set_delimiter = dval;
503 break;
504 default:
505 break;
506 }
507 break;
508 default:
509 break;
510 }
511 }
512 return (0);
513 }
514
515 int
hid_get_item(hid_data_t s,hid_item_t * h)516 hid_get_item(hid_data_t s, hid_item_t *h)
517 {
518 int r;
519
520 for (;;) {
521 r = hid_get_item_raw(s, h);
522 if (r <= 0 || s->reportid == -1 || h->report_ID == s->reportid)
523 break;
524 }
525 return (r);
526 }
527
528 int
hid_report_size(report_desc_t r,enum hid_kind k,int id)529 hid_report_size(report_desc_t r, enum hid_kind k, int id)
530 {
531 struct hid_data *d;
532 struct hid_item h;
533 uint32_t temp;
534 uint32_t hpos;
535 uint32_t lpos;
536 int report_id = 0;
537
538 hpos = 0;
539 lpos = 0xFFFFFFFF;
540
541 memset(&h, 0, sizeof h);
542 for (d = hid_start_parse(r, 1 << k, id); hid_get_item(d, &h); ) {
543 if (h.kind == k) {
544 /* compute minimum */
545 if (lpos > h.pos)
546 lpos = h.pos;
547 /* compute end position */
548 temp = h.pos + (h.report_size * h.report_count);
549 /* compute maximum */
550 if (hpos < temp)
551 hpos = temp;
552 if (h.report_ID != 0)
553 report_id = 1;
554 }
555 }
556 hid_end_parse(d);
557
558 /* safety check - can happen in case of currupt descriptors */
559 if (lpos > hpos)
560 temp = 0;
561 else
562 temp = hpos - lpos;
563
564 /* return length in bytes rounded up */
565 return ((temp + 7) / 8 + report_id);
566 }
567
568 int
hid_locate(report_desc_t desc,unsigned int u,enum hid_kind k,hid_item_t * h,int id)569 hid_locate(report_desc_t desc, unsigned int u, enum hid_kind k,
570 hid_item_t *h, int id)
571 {
572 struct hid_data *d;
573
574 for (d = hid_start_parse(desc, 1 << k, id); hid_get_item(d, h); ) {
575 if (h->kind == k && !(h->flags & HIO_CONST) && h->usage == u) {
576 hid_end_parse(d);
577 return (1);
578 }
579 }
580 hid_end_parse(d);
581 h->report_size = 0;
582 return (0);
583 }
584