xref: /openbmc/linux/drivers/s390/char/keyboard.c (revision 22246614)
1 /*
2  *  drivers/s390/char/keyboard.c
3  *    ebcdic keycode functions for s390 console drivers
4  *
5  *  S390 version
6  *    Copyright (C) 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
7  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
8  */
9 
10 #include <linux/module.h>
11 #include <linux/sched.h>
12 #include <linux/sysrq.h>
13 
14 #include <linux/consolemap.h>
15 #include <linux/kbd_kern.h>
16 #include <linux/kbd_diacr.h>
17 #include <asm/uaccess.h>
18 
19 #include "keyboard.h"
20 
21 /*
22  * Handler Tables.
23  */
24 #define K_HANDLERS\
25 	k_self,		k_fn,		k_spec,		k_ignore,\
26 	k_dead,		k_ignore,	k_ignore,	k_ignore,\
27 	k_ignore,	k_ignore,	k_ignore,	k_ignore,\
28 	k_ignore,	k_ignore,	k_ignore,	k_ignore
29 
30 typedef void (k_handler_fn)(struct kbd_data *, unsigned char);
31 static k_handler_fn K_HANDLERS;
32 static k_handler_fn *k_handler[16] = { K_HANDLERS };
33 
34 /* maximum values each key_handler can handle */
35 static const int kbd_max_vals[] = {
36 	255, ARRAY_SIZE(func_table) - 1, NR_FN_HANDLER - 1, 0,
37 	NR_DEAD - 1, 0, 0, 0, 0, 0, 0, 0, 0, 0
38 };
39 static const int KBD_NR_TYPES = ARRAY_SIZE(kbd_max_vals);
40 
41 static unsigned char ret_diacr[NR_DEAD] = {
42 	'`', '\'', '^', '~', '"', ','
43 };
44 
45 /*
46  * Alloc/free of kbd_data structures.
47  */
48 struct kbd_data *
49 kbd_alloc(void) {
50 	struct kbd_data *kbd;
51 	int i, len;
52 
53 	kbd = kzalloc(sizeof(struct kbd_data), GFP_KERNEL);
54 	if (!kbd)
55 		goto out;
56 	kbd->key_maps = kzalloc(sizeof(key_maps), GFP_KERNEL);
57 	if (!kbd->key_maps)
58 		goto out_kbd;
59 	for (i = 0; i < ARRAY_SIZE(key_maps); i++) {
60 		if (key_maps[i]) {
61 			kbd->key_maps[i] =
62 				kmalloc(sizeof(u_short)*NR_KEYS, GFP_KERNEL);
63 			if (!kbd->key_maps[i])
64 				goto out_maps;
65 			memcpy(kbd->key_maps[i], key_maps[i],
66 			       sizeof(u_short)*NR_KEYS);
67 		}
68 	}
69 	kbd->func_table = kzalloc(sizeof(func_table), GFP_KERNEL);
70 	if (!kbd->func_table)
71 		goto out_maps;
72 	for (i = 0; i < ARRAY_SIZE(func_table); i++) {
73 		if (func_table[i]) {
74 			len = strlen(func_table[i]) + 1;
75 			kbd->func_table[i] = kmalloc(len, GFP_KERNEL);
76 			if (!kbd->func_table[i])
77 				goto out_func;
78 			memcpy(kbd->func_table[i], func_table[i], len);
79 		}
80 	}
81 	kbd->fn_handler =
82 		kzalloc(sizeof(fn_handler_fn *) * NR_FN_HANDLER, GFP_KERNEL);
83 	if (!kbd->fn_handler)
84 		goto out_func;
85 	kbd->accent_table =
86 		kmalloc(sizeof(struct kbdiacruc)*MAX_DIACR, GFP_KERNEL);
87 	if (!kbd->accent_table)
88 		goto out_fn_handler;
89 	memcpy(kbd->accent_table, accent_table,
90 	       sizeof(struct kbdiacruc)*MAX_DIACR);
91 	kbd->accent_table_size = accent_table_size;
92 	return kbd;
93 
94 out_fn_handler:
95 	kfree(kbd->fn_handler);
96 out_func:
97 	for (i = 0; i < ARRAY_SIZE(func_table); i++)
98 		kfree(kbd->func_table[i]);
99 	kfree(kbd->func_table);
100 out_maps:
101 	for (i = 0; i < ARRAY_SIZE(key_maps); i++)
102 		kfree(kbd->key_maps[i]);
103 	kfree(kbd->key_maps);
104 out_kbd:
105 	kfree(kbd);
106 out:
107 	return NULL;
108 }
109 
110 void
111 kbd_free(struct kbd_data *kbd)
112 {
113 	int i;
114 
115 	kfree(kbd->accent_table);
116 	kfree(kbd->fn_handler);
117 	for (i = 0; i < ARRAY_SIZE(func_table); i++)
118 		kfree(kbd->func_table[i]);
119 	kfree(kbd->func_table);
120 	for (i = 0; i < ARRAY_SIZE(key_maps); i++)
121 		kfree(kbd->key_maps[i]);
122 	kfree(kbd->key_maps);
123 	kfree(kbd);
124 }
125 
126 /*
127  * Generate ascii -> ebcdic translation table from kbd_data.
128  */
129 void
130 kbd_ascebc(struct kbd_data *kbd, unsigned char *ascebc)
131 {
132 	unsigned short *keymap, keysym;
133 	int i, j, k;
134 
135 	memset(ascebc, 0x40, 256);
136 	for (i = 0; i < ARRAY_SIZE(key_maps); i++) {
137 		keymap = kbd->key_maps[i];
138 		if (!keymap)
139 			continue;
140 		for (j = 0; j < NR_KEYS; j++) {
141 			k = ((i & 1) << 7) + j;
142 			keysym = keymap[j];
143 			if (KTYP(keysym) == (KT_LATIN | 0xf0) ||
144 			    KTYP(keysym) == (KT_LETTER | 0xf0))
145 				ascebc[KVAL(keysym)] = k;
146 			else if (KTYP(keysym) == (KT_DEAD | 0xf0))
147 				ascebc[ret_diacr[KVAL(keysym)]] = k;
148 		}
149 	}
150 }
151 
152 #if 0
153 /*
154  * Generate ebcdic -> ascii translation table from kbd_data.
155  */
156 void
157 kbd_ebcasc(struct kbd_data *kbd, unsigned char *ebcasc)
158 {
159 	unsigned short *keymap, keysym;
160 	int i, j, k;
161 
162 	memset(ebcasc, ' ', 256);
163 	for (i = 0; i < ARRAY_SIZE(key_maps); i++) {
164 		keymap = kbd->key_maps[i];
165 		if (!keymap)
166 			continue;
167 		for (j = 0; j < NR_KEYS; j++) {
168 			keysym = keymap[j];
169 			k = ((i & 1) << 7) + j;
170 			if (KTYP(keysym) == (KT_LATIN | 0xf0) ||
171 			    KTYP(keysym) == (KT_LETTER | 0xf0))
172 				ebcasc[k] = KVAL(keysym);
173 			else if (KTYP(keysym) == (KT_DEAD | 0xf0))
174 				ebcasc[k] = ret_diacr[KVAL(keysym)];
175 		}
176 	}
177 }
178 #endif
179 
180 /*
181  * We have a combining character DIACR here, followed by the character CH.
182  * If the combination occurs in the table, return the corresponding value.
183  * Otherwise, if CH is a space or equals DIACR, return DIACR.
184  * Otherwise, conclude that DIACR was not combining after all,
185  * queue it and return CH.
186  */
187 static unsigned int
188 handle_diacr(struct kbd_data *kbd, unsigned int ch)
189 {
190 	int i, d;
191 
192 	d = kbd->diacr;
193 	kbd->diacr = 0;
194 
195 	for (i = 0; i < kbd->accent_table_size; i++) {
196 		if (kbd->accent_table[i].diacr == d &&
197 		    kbd->accent_table[i].base == ch)
198 			return kbd->accent_table[i].result;
199 	}
200 
201 	if (ch == ' ' || ch == d)
202 		return d;
203 
204 	kbd_put_queue(kbd->tty, d);
205 	return ch;
206 }
207 
208 /*
209  * Handle dead key.
210  */
211 static void
212 k_dead(struct kbd_data *kbd, unsigned char value)
213 {
214 	value = ret_diacr[value];
215 	kbd->diacr = (kbd->diacr ? handle_diacr(kbd, value) : value);
216 }
217 
218 /*
219  * Normal character handler.
220  */
221 static void
222 k_self(struct kbd_data *kbd, unsigned char value)
223 {
224 	if (kbd->diacr)
225 		value = handle_diacr(kbd, value);
226 	kbd_put_queue(kbd->tty, value);
227 }
228 
229 /*
230  * Special key handlers
231  */
232 static void
233 k_ignore(struct kbd_data *kbd, unsigned char value)
234 {
235 }
236 
237 /*
238  * Function key handler.
239  */
240 static void
241 k_fn(struct kbd_data *kbd, unsigned char value)
242 {
243 	if (kbd->func_table[value])
244 		kbd_puts_queue(kbd->tty, kbd->func_table[value]);
245 }
246 
247 static void
248 k_spec(struct kbd_data *kbd, unsigned char value)
249 {
250 	if (value >= NR_FN_HANDLER)
251 		return;
252 	if (kbd->fn_handler[value])
253 		kbd->fn_handler[value](kbd);
254 }
255 
256 /*
257  * Put utf8 character to tty flip buffer.
258  * UTF-8 is defined for words of up to 31 bits,
259  * but we need only 16 bits here
260  */
261 static void
262 to_utf8(struct tty_struct *tty, ushort c)
263 {
264 	if (c < 0x80)
265 		/*  0******* */
266 		kbd_put_queue(tty, c);
267 	else if (c < 0x800) {
268 		/* 110***** 10****** */
269 		kbd_put_queue(tty, 0xc0 | (c >> 6));
270 		kbd_put_queue(tty, 0x80 | (c & 0x3f));
271 	} else {
272 		/* 1110**** 10****** 10****** */
273 		kbd_put_queue(tty, 0xe0 | (c >> 12));
274 		kbd_put_queue(tty, 0x80 | ((c >> 6) & 0x3f));
275 		kbd_put_queue(tty, 0x80 | (c & 0x3f));
276 	}
277 }
278 
279 /*
280  * Process keycode.
281  */
282 void
283 kbd_keycode(struct kbd_data *kbd, unsigned int keycode)
284 {
285 	unsigned short keysym;
286 	unsigned char type, value;
287 
288 	if (!kbd || !kbd->tty)
289 		return;
290 
291 	if (keycode >= 384)
292 		keysym = kbd->key_maps[5][keycode - 384];
293 	else if (keycode >= 256)
294 		keysym = kbd->key_maps[4][keycode - 256];
295 	else if (keycode >= 128)
296 		keysym = kbd->key_maps[1][keycode - 128];
297 	else
298 		keysym = kbd->key_maps[0][keycode];
299 
300 	type = KTYP(keysym);
301 	if (type >= 0xf0) {
302 		type -= 0xf0;
303 		if (type == KT_LETTER)
304 			type = KT_LATIN;
305 		value = KVAL(keysym);
306 #ifdef CONFIG_MAGIC_SYSRQ	       /* Handle the SysRq Hack */
307 		if (kbd->sysrq) {
308 			if (kbd->sysrq == K(KT_LATIN, '-')) {
309 				kbd->sysrq = 0;
310 				handle_sysrq(value, kbd->tty);
311 				return;
312 			}
313 			if (value == '-') {
314 				kbd->sysrq = K(KT_LATIN, '-');
315 				return;
316 			}
317 			/* Incomplete sysrq sequence. */
318 			(*k_handler[KTYP(kbd->sysrq)])(kbd, KVAL(kbd->sysrq));
319 			kbd->sysrq = 0;
320 		} else if ((type == KT_LATIN && value == '^') ||
321 			   (type == KT_DEAD && ret_diacr[value] == '^')) {
322 			kbd->sysrq = K(type, value);
323 			return;
324 		}
325 #endif
326 		(*k_handler[type])(kbd, value);
327 	} else
328 		to_utf8(kbd->tty, keysym);
329 }
330 
331 /*
332  * Ioctl stuff.
333  */
334 static int
335 do_kdsk_ioctl(struct kbd_data *kbd, struct kbentry __user *user_kbe,
336 	      int cmd, int perm)
337 {
338 	struct kbentry tmp;
339 	ushort *key_map, val, ov;
340 
341 	if (copy_from_user(&tmp, user_kbe, sizeof(struct kbentry)))
342 		return -EFAULT;
343 #if NR_KEYS < 256
344 	if (tmp.kb_index >= NR_KEYS)
345 		return -EINVAL;
346 #endif
347 #if MAX_NR_KEYMAPS < 256
348 	if (tmp.kb_table >= MAX_NR_KEYMAPS)
349 		return -EINVAL;
350 #endif
351 
352 	switch (cmd) {
353 	case KDGKBENT:
354 		key_map = kbd->key_maps[tmp.kb_table];
355 		if (key_map) {
356 		    val = U(key_map[tmp.kb_index]);
357 		    if (KTYP(val) >= KBD_NR_TYPES)
358 			val = K_HOLE;
359 		} else
360 		    val = (tmp.kb_index ? K_HOLE : K_NOSUCHMAP);
361 		return put_user(val, &user_kbe->kb_value);
362 	case KDSKBENT:
363 		if (!perm)
364 			return -EPERM;
365 		if (!tmp.kb_index && tmp.kb_value == K_NOSUCHMAP) {
366 			/* disallocate map */
367 			key_map = kbd->key_maps[tmp.kb_table];
368 			if (key_map) {
369 			    kbd->key_maps[tmp.kb_table] = NULL;
370 			    kfree(key_map);
371 			}
372 			break;
373 		}
374 
375 		if (KTYP(tmp.kb_value) >= KBD_NR_TYPES)
376 			return -EINVAL;
377 		if (KVAL(tmp.kb_value) > kbd_max_vals[KTYP(tmp.kb_value)])
378 			return -EINVAL;
379 
380 		if (!(key_map = kbd->key_maps[tmp.kb_table])) {
381 			int j;
382 
383 			key_map = kmalloc(sizeof(plain_map),
384 						     GFP_KERNEL);
385 			if (!key_map)
386 				return -ENOMEM;
387 			kbd->key_maps[tmp.kb_table] = key_map;
388 			for (j = 0; j < NR_KEYS; j++)
389 				key_map[j] = U(K_HOLE);
390 		}
391 		ov = U(key_map[tmp.kb_index]);
392 		if (tmp.kb_value == ov)
393 			break;	/* nothing to do */
394 		/*
395 		 * Attention Key.
396 		 */
397 		if (((ov == K_SAK) || (tmp.kb_value == K_SAK)) &&
398 		    !capable(CAP_SYS_ADMIN))
399 			return -EPERM;
400 		key_map[tmp.kb_index] = U(tmp.kb_value);
401 		break;
402 	}
403 	return 0;
404 }
405 
406 static int
407 do_kdgkb_ioctl(struct kbd_data *kbd, struct kbsentry __user *u_kbs,
408 	       int cmd, int perm)
409 {
410 	unsigned char kb_func;
411 	char *p;
412 	int len;
413 
414 	/* Get u_kbs->kb_func. */
415 	if (get_user(kb_func, &u_kbs->kb_func))
416 		return -EFAULT;
417 #if MAX_NR_FUNC < 256
418 	if (kb_func >= MAX_NR_FUNC)
419 		return -EINVAL;
420 #endif
421 
422 	switch (cmd) {
423 	case KDGKBSENT:
424 		p = kbd->func_table[kb_func];
425 		if (p) {
426 			len = strlen(p);
427 			if (len >= sizeof(u_kbs->kb_string))
428 				len = sizeof(u_kbs->kb_string) - 1;
429 			if (copy_to_user(u_kbs->kb_string, p, len))
430 				return -EFAULT;
431 		} else
432 			len = 0;
433 		if (put_user('\0', u_kbs->kb_string + len))
434 			return -EFAULT;
435 		break;
436 	case KDSKBSENT:
437 		if (!perm)
438 			return -EPERM;
439 		len = strnlen_user(u_kbs->kb_string,
440 				   sizeof(u_kbs->kb_string) - 1);
441 		if (!len)
442 			return -EFAULT;
443 		if (len > sizeof(u_kbs->kb_string) - 1)
444 			return -EINVAL;
445 		p = kmalloc(len + 1, GFP_KERNEL);
446 		if (!p)
447 			return -ENOMEM;
448 		if (copy_from_user(p, u_kbs->kb_string, len)) {
449 			kfree(p);
450 			return -EFAULT;
451 		}
452 		p[len] = 0;
453 		kfree(kbd->func_table[kb_func]);
454 		kbd->func_table[kb_func] = p;
455 		break;
456 	}
457 	return 0;
458 }
459 
460 int
461 kbd_ioctl(struct kbd_data *kbd, struct file *file,
462 	  unsigned int cmd, unsigned long arg)
463 {
464 	void __user *argp;
465 	int ct, perm;
466 
467 	argp = (void __user *)arg;
468 
469 	/*
470 	 * To have permissions to do most of the vt ioctls, we either have
471 	 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
472 	 */
473 	perm = current->signal->tty == kbd->tty || capable(CAP_SYS_TTY_CONFIG);
474 	switch (cmd) {
475 	case KDGKBTYPE:
476 		return put_user(KB_101, (char __user *)argp);
477 	case KDGKBENT:
478 	case KDSKBENT:
479 		return do_kdsk_ioctl(kbd, argp, cmd, perm);
480 	case KDGKBSENT:
481 	case KDSKBSENT:
482 		return do_kdgkb_ioctl(kbd, argp, cmd, perm);
483 	case KDGKBDIACR:
484 	{
485 		struct kbdiacrs __user *a = argp;
486 		struct kbdiacr diacr;
487 		int i;
488 
489 		if (put_user(kbd->accent_table_size, &a->kb_cnt))
490 			return -EFAULT;
491 		for (i = 0; i < kbd->accent_table_size; i++) {
492 			diacr.diacr = kbd->accent_table[i].diacr;
493 			diacr.base = kbd->accent_table[i].base;
494 			diacr.result = kbd->accent_table[i].result;
495 			if (copy_to_user(a->kbdiacr + i, &diacr, sizeof(struct kbdiacr)))
496 			return -EFAULT;
497 		}
498 		return 0;
499 	}
500 	case KDGKBDIACRUC:
501 	{
502 		struct kbdiacrsuc __user *a = argp;
503 
504 		ct = kbd->accent_table_size;
505 		if (put_user(ct, &a->kb_cnt))
506 			return -EFAULT;
507 		if (copy_to_user(a->kbdiacruc, kbd->accent_table,
508 				 ct * sizeof(struct kbdiacruc)))
509 			return -EFAULT;
510 		return 0;
511 	}
512 	case KDSKBDIACR:
513 	{
514 		struct kbdiacrs __user *a = argp;
515 		struct kbdiacr diacr;
516 		int i;
517 
518 		if (!perm)
519 			return -EPERM;
520 		if (get_user(ct, &a->kb_cnt))
521 			return -EFAULT;
522 		if (ct >= MAX_DIACR)
523 			return -EINVAL;
524 		kbd->accent_table_size = ct;
525 		for (i = 0; i < ct; i++) {
526 			if (copy_from_user(&diacr, a->kbdiacr + i, sizeof(struct kbdiacr)))
527 				return -EFAULT;
528 			kbd->accent_table[i].diacr = diacr.diacr;
529 			kbd->accent_table[i].base = diacr.base;
530 			kbd->accent_table[i].result = diacr.result;
531 		}
532 		return 0;
533 	}
534 	case KDSKBDIACRUC:
535 	{
536 		struct kbdiacrsuc __user *a = argp;
537 
538 		if (!perm)
539 			return -EPERM;
540 		if (get_user(ct, &a->kb_cnt))
541 			return -EFAULT;
542 		if (ct >= MAX_DIACR)
543 			return -EINVAL;
544 		kbd->accent_table_size = ct;
545 		if (copy_from_user(kbd->accent_table, a->kbdiacruc,
546 				   ct * sizeof(struct kbdiacruc)))
547 			return -EFAULT;
548 		return 0;
549 	}
550 	default:
551 		return -ENOIOCTLCMD;
552 	}
553 }
554 
555 EXPORT_SYMBOL(kbd_ioctl);
556 EXPORT_SYMBOL(kbd_ascebc);
557 EXPORT_SYMBOL(kbd_free);
558 EXPORT_SYMBOL(kbd_alloc);
559 EXPORT_SYMBOL(kbd_keycode);
560