xref: /openbmc/linux/drivers/s390/char/keyboard.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2) 
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/config.h>
11 #include <linux/module.h>
12 #include <linux/sched.h>
13 #include <linux/sysrq.h>
14 
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 = kmalloc(sizeof(struct kbd_data), GFP_KERNEL);
54 	if (!kbd)
55 		goto out;
56 	memset(kbd, 0, sizeof(struct kbd_data));
57 	kbd->key_maps = kmalloc(sizeof(key_maps), GFP_KERNEL);
58 	if (!key_maps)
59 		goto out_kbd;
60 	memset(kbd->key_maps, 0, sizeof(key_maps));
61 	for (i = 0; i < ARRAY_SIZE(key_maps); i++) {
62 		if (key_maps[i]) {
63 			kbd->key_maps[i] =
64 				kmalloc(sizeof(u_short)*NR_KEYS, GFP_KERNEL);
65 			if (!kbd->key_maps[i])
66 				goto out_maps;
67 			memcpy(kbd->key_maps[i], key_maps[i],
68 			       sizeof(u_short)*NR_KEYS);
69 		}
70 	}
71 	kbd->func_table = kmalloc(sizeof(func_table), GFP_KERNEL);
72 	if (!kbd->func_table)
73 		goto out_maps;
74 	memset(kbd->func_table, 0, sizeof(func_table));
75 	for (i = 0; i < ARRAY_SIZE(func_table); i++) {
76 		if (func_table[i]) {
77 			len = strlen(func_table[i]) + 1;
78 			kbd->func_table[i] = kmalloc(len, GFP_KERNEL);
79 			if (!kbd->func_table[i])
80 				goto out_func;
81 			memcpy(kbd->func_table[i], func_table[i], len);
82 		}
83 	}
84 	kbd->fn_handler =
85 		kmalloc(sizeof(fn_handler_fn *) * NR_FN_HANDLER, GFP_KERNEL);
86 	if (!kbd->fn_handler)
87 		goto out_func;
88 	memset(kbd->fn_handler, 0, sizeof(fn_handler_fn *) * NR_FN_HANDLER);
89 	kbd->accent_table =
90 		kmalloc(sizeof(struct kbdiacr)*MAX_DIACR, GFP_KERNEL);
91 	if (!kbd->accent_table)
92 		goto out_fn_handler;
93 	memcpy(kbd->accent_table, accent_table,
94 	       sizeof(struct kbdiacr)*MAX_DIACR);
95 	kbd->accent_table_size = accent_table_size;
96 	return kbd;
97 
98 out_fn_handler:
99 	kfree(kbd->fn_handler);
100 out_func:
101 	for (i = 0; i < ARRAY_SIZE(func_table); i++)
102 		if (kbd->func_table[i])
103 			kfree(kbd->func_table[i]);
104 	kfree(kbd->func_table);
105 out_maps:
106 	for (i = 0; i < ARRAY_SIZE(key_maps); i++)
107 		if (kbd->key_maps[i])
108 			kfree(kbd->key_maps[i]);
109 	kfree(kbd->key_maps);
110 out_kbd:
111 	kfree(kbd);
112 out:
113 	return 0;
114 }
115 
116 void
117 kbd_free(struct kbd_data *kbd)
118 {
119 	int i;
120 
121 	kfree(kbd->accent_table);
122 	kfree(kbd->fn_handler);
123 	for (i = 0; i < ARRAY_SIZE(func_table); i++)
124 		if (kbd->func_table[i])
125 			kfree(kbd->func_table[i]);
126 	kfree(kbd->func_table);
127 	for (i = 0; i < ARRAY_SIZE(key_maps); i++)
128 		if (kbd->key_maps[i])
129 			kfree(kbd->key_maps[i]);
130 	kfree(kbd->key_maps);
131 	kfree(kbd);
132 }
133 
134 /*
135  * Generate ascii -> ebcdic translation table from kbd_data.
136  */
137 void
138 kbd_ascebc(struct kbd_data *kbd, unsigned char *ascebc)
139 {
140 	unsigned short *keymap, keysym;
141 	int i, j, k;
142 
143 	memset(ascebc, 0x40, 256);
144 	for (i = 0; i < ARRAY_SIZE(key_maps); i++) {
145 		keymap = kbd->key_maps[i];
146 		if (!keymap)
147 			continue;
148 		for (j = 0; j < NR_KEYS; j++) {
149 			k = ((i & 1) << 7) + j;
150 			keysym = keymap[j];
151 			if (KTYP(keysym) == (KT_LATIN | 0xf0) ||
152 			    KTYP(keysym) == (KT_LETTER | 0xf0))
153 				ascebc[KVAL(keysym)] = k;
154 			else if (KTYP(keysym) == (KT_DEAD | 0xf0))
155 				ascebc[ret_diacr[KVAL(keysym)]] = k;
156 		}
157 	}
158 }
159 
160 /*
161  * Generate ebcdic -> ascii translation table from kbd_data.
162  */
163 void
164 kbd_ebcasc(struct kbd_data *kbd, unsigned char *ebcasc)
165 {
166 	unsigned short *keymap, keysym;
167 	int i, j, k;
168 
169 	memset(ebcasc, ' ', 256);
170 	for (i = 0; i < ARRAY_SIZE(key_maps); i++) {
171 		keymap = kbd->key_maps[i];
172 		if (!keymap)
173 			continue;
174 		for (j = 0; j < NR_KEYS; j++) {
175 			keysym = keymap[j];
176 			k = ((i & 1) << 7) + j;
177 			if (KTYP(keysym) == (KT_LATIN | 0xf0) ||
178 			    KTYP(keysym) == (KT_LETTER | 0xf0))
179 				ebcasc[k] = KVAL(keysym);
180 			else if (KTYP(keysym) == (KT_DEAD | 0xf0))
181 				ebcasc[k] = ret_diacr[KVAL(keysym)];
182 		}
183 	}
184 }
185 
186 /*
187  * We have a combining character DIACR here, followed by the character CH.
188  * If the combination occurs in the table, return the corresponding value.
189  * Otherwise, if CH is a space or equals DIACR, return DIACR.
190  * Otherwise, conclude that DIACR was not combining after all,
191  * queue it and return CH.
192  */
193 static unsigned char
194 handle_diacr(struct kbd_data *kbd, unsigned char ch)
195 {
196 	int i, d;
197 
198 	d = kbd->diacr;
199 	kbd->diacr = 0;
200 
201 	for (i = 0; i < kbd->accent_table_size; i++) {
202 		if (kbd->accent_table[i].diacr == d &&
203 		    kbd->accent_table[i].base == ch)
204 			return kbd->accent_table[i].result;
205 	}
206 
207 	if (ch == ' ' || ch == d)
208 		return d;
209 
210 	kbd_put_queue(kbd->tty, d);
211 	return ch;
212 }
213 
214 /*
215  * Handle dead key.
216  */
217 static void
218 k_dead(struct kbd_data *kbd, unsigned char value)
219 {
220 	value = ret_diacr[value];
221 	kbd->diacr = (kbd->diacr ? handle_diacr(kbd, value) : value);
222 }
223 
224 /*
225  * Normal character handler.
226  */
227 static void
228 k_self(struct kbd_data *kbd, unsigned char value)
229 {
230 	if (kbd->diacr)
231 		value = handle_diacr(kbd, value);
232 	kbd_put_queue(kbd->tty, value);
233 }
234 
235 /*
236  * Special key handlers
237  */
238 static void
239 k_ignore(struct kbd_data *kbd, unsigned char value)
240 {
241 }
242 
243 /*
244  * Function key handler.
245  */
246 static void
247 k_fn(struct kbd_data *kbd, unsigned char value)
248 {
249 	if (kbd->func_table[value])
250 		kbd_puts_queue(kbd->tty, kbd->func_table[value]);
251 }
252 
253 static void
254 k_spec(struct kbd_data *kbd, unsigned char value)
255 {
256 	if (value >= NR_FN_HANDLER)
257 		return;
258 	if (kbd->fn_handler[value])
259 		kbd->fn_handler[value](kbd);
260 }
261 
262 /*
263  * Put utf8 character to tty flip buffer.
264  * UTF-8 is defined for words of up to 31 bits,
265  * but we need only 16 bits here
266  */
267 static void
268 to_utf8(struct tty_struct *tty, ushort c)
269 {
270 	if (c < 0x80)
271 		/*  0******* */
272 		kbd_put_queue(tty, c);
273 	else if (c < 0x800) {
274 		/* 110***** 10****** */
275 		kbd_put_queue(tty, 0xc0 | (c >> 6));
276 		kbd_put_queue(tty, 0x80 | (c & 0x3f));
277 	} else {
278 		/* 1110**** 10****** 10****** */
279 		kbd_put_queue(tty, 0xe0 | (c >> 12));
280 		kbd_put_queue(tty, 0x80 | ((c >> 6) & 0x3f));
281 		kbd_put_queue(tty, 0x80 | (c & 0x3f));
282 	}
283 }
284 
285 /*
286  * Process keycode.
287  */
288 void
289 kbd_keycode(struct kbd_data *kbd, unsigned int keycode)
290 {
291 	unsigned short keysym;
292 	unsigned char type, value;
293 
294 	if (!kbd || !kbd->tty)
295 		return;
296 
297 	if (keycode >= 384)
298 		keysym = kbd->key_maps[5][keycode - 384];
299 	else if (keycode >= 256)
300 		keysym = kbd->key_maps[4][keycode - 256];
301 	else if (keycode >= 128)
302 		keysym = kbd->key_maps[1][keycode - 128];
303 	else
304 		keysym = kbd->key_maps[0][keycode];
305 
306 	type = KTYP(keysym);
307 	if (type >= 0xf0) {
308 		type -= 0xf0;
309 		if (type == KT_LETTER)
310 			type = KT_LATIN;
311 		value = KVAL(keysym);
312 #ifdef CONFIG_MAGIC_SYSRQ	       /* Handle the SysRq Hack */
313 		if (kbd->sysrq) {
314 			if (kbd->sysrq == K(KT_LATIN, '-')) {
315 				kbd->sysrq = 0;
316 				handle_sysrq(value, 0, kbd->tty);
317 				return;
318 			}
319 			if (value == '-') {
320 				kbd->sysrq = K(KT_LATIN, '-');
321 				return;
322 			}
323 			/* Incomplete sysrq sequence. */
324 			(*k_handler[KTYP(kbd->sysrq)])(kbd, KVAL(kbd->sysrq));
325 			kbd->sysrq = 0;
326 		} else if ((type == KT_LATIN && value == '^') ||
327 			   (type == KT_DEAD && ret_diacr[value] == '^')) {
328 			kbd->sysrq = K(type, value);
329 			return;
330 		}
331 #endif
332 		(*k_handler[type])(kbd, value);
333 	} else
334 		to_utf8(kbd->tty, keysym);
335 }
336 
337 /*
338  * Ioctl stuff.
339  */
340 static int
341 do_kdsk_ioctl(struct kbd_data *kbd, struct kbentry __user *user_kbe,
342 	      int cmd, int perm)
343 {
344 	struct kbentry tmp;
345 	ushort *key_map, val, ov;
346 
347 	if (copy_from_user(&tmp, user_kbe, sizeof(struct kbentry)))
348 		return -EFAULT;
349 #if NR_KEYS < 256
350 	if (tmp.kb_index >= NR_KEYS)
351 		return -EINVAL;
352 #endif
353 #if MAX_NR_KEYMAPS < 256
354 	if (tmp.kb_table >= MAX_NR_KEYMAPS)
355 		return -EINVAL;
356 #endif
357 
358 	switch (cmd) {
359 	case KDGKBENT:
360 		key_map = kbd->key_maps[tmp.kb_table];
361 		if (key_map) {
362 		    val = U(key_map[tmp.kb_index]);
363 		    if (KTYP(val) >= KBD_NR_TYPES)
364 			val = K_HOLE;
365 		} else
366 		    val = (tmp.kb_index ? K_HOLE : K_NOSUCHMAP);
367 		return put_user(val, &user_kbe->kb_value);
368 	case KDSKBENT:
369 		if (!perm)
370 			return -EPERM;
371 		if (!tmp.kb_index && tmp.kb_value == K_NOSUCHMAP) {
372 			/* disallocate map */
373 			key_map = kbd->key_maps[tmp.kb_table];
374 			if (key_map) {
375 			    kbd->key_maps[tmp.kb_table] = 0;
376 			    kfree(key_map);
377 			}
378 			break;
379 		}
380 
381 		if (KTYP(tmp.kb_value) >= KBD_NR_TYPES)
382 			return -EINVAL;
383 		if (KVAL(tmp.kb_value) > kbd_max_vals[KTYP(tmp.kb_value)])
384 			return -EINVAL;
385 
386 		if (!(key_map = kbd->key_maps[tmp.kb_table])) {
387 			int j;
388 
389 			key_map = (ushort *) kmalloc(sizeof(plain_map),
390 						     GFP_KERNEL);
391 			if (!key_map)
392 				return -ENOMEM;
393 			kbd->key_maps[tmp.kb_table] = key_map;
394 			for (j = 0; j < NR_KEYS; j++)
395 				key_map[j] = U(K_HOLE);
396 		}
397 		ov = U(key_map[tmp.kb_index]);
398 		if (tmp.kb_value == ov)
399 			break;	/* nothing to do */
400 		/*
401 		 * Attention Key.
402 		 */
403 		if (((ov == K_SAK) || (tmp.kb_value == K_SAK)) &&
404 		    !capable(CAP_SYS_ADMIN))
405 			return -EPERM;
406 		key_map[tmp.kb_index] = U(tmp.kb_value);
407 		break;
408 	}
409 	return 0;
410 }
411 
412 static int
413 do_kdgkb_ioctl(struct kbd_data *kbd, struct kbsentry __user *u_kbs,
414 	       int cmd, int perm)
415 {
416 	unsigned char kb_func;
417 	char *p;
418 	int len;
419 
420 	/* Get u_kbs->kb_func. */
421 	if (get_user(kb_func, &u_kbs->kb_func))
422 		return -EFAULT;
423 #if MAX_NR_FUNC < 256
424 	if (kb_func >= MAX_NR_FUNC)
425 		return -EINVAL;
426 #endif
427 
428 	switch (cmd) {
429 	case KDGKBSENT:
430 		p = kbd->func_table[kb_func];
431 		if (p) {
432 			len = strlen(p);
433 			if (len >= sizeof(u_kbs->kb_string))
434 				len = sizeof(u_kbs->kb_string) - 1;
435 			if (copy_to_user(u_kbs->kb_string, p, len))
436 				return -EFAULT;
437 		} else
438 			len = 0;
439 		if (put_user('\0', u_kbs->kb_string + len))
440 			return -EFAULT;
441 		break;
442 	case KDSKBSENT:
443 		if (!perm)
444 			return -EPERM;
445 		len = strnlen_user(u_kbs->kb_string,
446 				   sizeof(u_kbs->kb_string) - 1);
447 		p = kmalloc(len, GFP_KERNEL);
448 		if (!p)
449 			return -ENOMEM;
450 		if (copy_from_user(p, u_kbs->kb_string, len)) {
451 			kfree(p);
452 			return -EFAULT;
453 		}
454 		p[len] = 0;
455 		if (kbd->func_table[kb_func])
456 			kfree(kbd->func_table[kb_func]);
457 		kbd->func_table[kb_func] = p;
458 		break;
459 	}
460 	return 0;
461 }
462 
463 int
464 kbd_ioctl(struct kbd_data *kbd, struct file *file,
465 	  unsigned int cmd, unsigned long arg)
466 {
467 	struct kbdiacrs __user *a;
468 	void __user *argp;
469 	int ct, perm;
470 
471 	argp = (void __user *)arg;
472 
473 	/*
474 	 * To have permissions to do most of the vt ioctls, we either have
475 	 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
476 	 */
477 	perm = current->signal->tty == kbd->tty || capable(CAP_SYS_TTY_CONFIG);
478 	switch (cmd) {
479 	case KDGKBTYPE:
480 		return put_user(KB_101, (char __user *)argp);
481 	case KDGKBENT:
482 	case KDSKBENT:
483 		return do_kdsk_ioctl(kbd, argp, cmd, perm);
484 	case KDGKBSENT:
485 	case KDSKBSENT:
486 		return do_kdgkb_ioctl(kbd, argp, cmd, perm);
487 	case KDGKBDIACR:
488 		a = argp;
489 
490 		if (put_user(kbd->accent_table_size, &a->kb_cnt))
491 			return -EFAULT;
492 		ct = kbd->accent_table_size;
493 		if (copy_to_user(a->kbdiacr, kbd->accent_table,
494 				 ct * sizeof(struct kbdiacr)))
495 			return -EFAULT;
496 		return 0;
497 	case KDSKBDIACR:
498 		a = argp;
499 		if (!perm)
500 			return -EPERM;
501 		if (get_user(ct, &a->kb_cnt))
502 			return -EFAULT;
503 		if (ct >= MAX_DIACR)
504 			return -EINVAL;
505 		kbd->accent_table_size = ct;
506 		if (copy_from_user(kbd->accent_table, a->kbdiacr,
507 				   ct * sizeof(struct kbdiacr)))
508 			return -EFAULT;
509 		return 0;
510 	default:
511 		return -ENOIOCTLCMD;
512 	}
513 }
514 
515 EXPORT_SYMBOL(kbd_ioctl);
516 EXPORT_SYMBOL(kbd_ascebc);
517 EXPORT_SYMBOL(kbd_free);
518 EXPORT_SYMBOL(kbd_alloc);
519 EXPORT_SYMBOL(kbd_keycode);
520