keyboard.c revision 172411f10c25bbd81b19f67566af6a7f549f46a9 
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
30typedef void (k_handler_fn)(struct kbd_data *, unsigned char);
31static k_handler_fn K_HANDLERS;
32static k_handler_fn *k_handler[16] = { K_HANDLERS };
33
34/* maximum values each key_handler can handle */
35static 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};
39static const int KBD_NR_TYPES = ARRAY_SIZE(kbd_max_vals);
40
41static unsigned char ret_diacr[NR_DEAD] = {
42	'`', '\'', '^', '~', '"', ','
43};
44
45/*
46 * Alloc/free of kbd_data structures.
47 */
48struct kbd_data *
49kbd_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
98out_fn_handler:
99	kfree(kbd->fn_handler);
100out_func:
101	for (i = 0; i < ARRAY_SIZE(func_table); i++)
102		kfree(kbd->func_table[i]);
103	kfree(kbd->func_table);
104out_maps:
105	for (i = 0; i < ARRAY_SIZE(key_maps); i++)
106		kfree(kbd->key_maps[i]);
107	kfree(kbd->key_maps);
108out_kbd:
109	kfree(kbd);
110out:
111	return 0;
112}
113
114void
115kbd_free(struct kbd_data *kbd)
116{
117	int i;
118
119	kfree(kbd->accent_table);
120	kfree(kbd->fn_handler);
121	for (i = 0; i < ARRAY_SIZE(func_table); i++)
122		kfree(kbd->func_table[i]);
123	kfree(kbd->func_table);
124	for (i = 0; i < ARRAY_SIZE(key_maps); i++)
125		kfree(kbd->key_maps[i]);
126	kfree(kbd->key_maps);
127	kfree(kbd);
128}
129
130/*
131 * Generate ascii -> ebcdic translation table from kbd_data.
132 */
133void
134kbd_ascebc(struct kbd_data *kbd, unsigned char *ascebc)
135{
136	unsigned short *keymap, keysym;
137	int i, j, k;
138
139	memset(ascebc, 0x40, 256);
140	for (i = 0; i < ARRAY_SIZE(key_maps); i++) {
141		keymap = kbd->key_maps[i];
142		if (!keymap)
143			continue;
144		for (j = 0; j < NR_KEYS; j++) {
145			k = ((i & 1) << 7) + j;
146			keysym = keymap[j];
147			if (KTYP(keysym) == (KT_LATIN | 0xf0) ||
148			    KTYP(keysym) == (KT_LETTER | 0xf0))
149				ascebc[KVAL(keysym)] = k;
150			else if (KTYP(keysym) == (KT_DEAD | 0xf0))
151				ascebc[ret_diacr[KVAL(keysym)]] = k;
152		}
153	}
154}
155
156/*
157 * Generate ebcdic -> ascii translation table from kbd_data.
158 */
159void
160kbd_ebcasc(struct kbd_data *kbd, unsigned char *ebcasc)
161{
162	unsigned short *keymap, keysym;
163	int i, j, k;
164
165	memset(ebcasc, ' ', 256);
166	for (i = 0; i < ARRAY_SIZE(key_maps); i++) {
167		keymap = kbd->key_maps[i];
168		if (!keymap)
169			continue;
170		for (j = 0; j < NR_KEYS; j++) {
171			keysym = keymap[j];
172			k = ((i & 1) << 7) + j;
173			if (KTYP(keysym) == (KT_LATIN | 0xf0) ||
174			    KTYP(keysym) == (KT_LETTER | 0xf0))
175				ebcasc[k] = KVAL(keysym);
176			else if (KTYP(keysym) == (KT_DEAD | 0xf0))
177				ebcasc[k] = ret_diacr[KVAL(keysym)];
178		}
179	}
180}
181
182/*
183 * We have a combining character DIACR here, followed by the character CH.
184 * If the combination occurs in the table, return the corresponding value.
185 * Otherwise, if CH is a space or equals DIACR, return DIACR.
186 * Otherwise, conclude that DIACR was not combining after all,
187 * queue it and return CH.
188 */
189static unsigned char
190handle_diacr(struct kbd_data *kbd, unsigned char ch)
191{
192	int i, d;
193
194	d = kbd->diacr;
195	kbd->diacr = 0;
196
197	for (i = 0; i < kbd->accent_table_size; i++) {
198		if (kbd->accent_table[i].diacr == d &&
199		    kbd->accent_table[i].base == ch)
200			return kbd->accent_table[i].result;
201	}
202
203	if (ch == ' ' || ch == d)
204		return d;
205
206	kbd_put_queue(kbd->tty, d);
207	return ch;
208}
209
210/*
211 * Handle dead key.
212 */
213static void
214k_dead(struct kbd_data *kbd, unsigned char value)
215{
216	value = ret_diacr[value];
217	kbd->diacr = (kbd->diacr ? handle_diacr(kbd, value) : value);
218}
219
220/*
221 * Normal character handler.
222 */
223static void
224k_self(struct kbd_data *kbd, unsigned char value)
225{
226	if (kbd->diacr)
227		value = handle_diacr(kbd, value);
228	kbd_put_queue(kbd->tty, value);
229}
230
231/*
232 * Special key handlers
233 */
234static void
235k_ignore(struct kbd_data *kbd, unsigned char value)
236{
237}
238
239/*
240 * Function key handler.
241 */
242static void
243k_fn(struct kbd_data *kbd, unsigned char value)
244{
245	if (kbd->func_table[value])
246		kbd_puts_queue(kbd->tty, kbd->func_table[value]);
247}
248
249static void
250k_spec(struct kbd_data *kbd, unsigned char value)
251{
252	if (value >= NR_FN_HANDLER)
253		return;
254	if (kbd->fn_handler[value])
255		kbd->fn_handler[value](kbd);
256}
257
258/*
259 * Put utf8 character to tty flip buffer.
260 * UTF-8 is defined for words of up to 31 bits,
261 * but we need only 16 bits here
262 */
263static void
264to_utf8(struct tty_struct *tty, ushort c)
265{
266	if (c < 0x80)
267		/*  0******* */
268		kbd_put_queue(tty, c);
269	else if (c < 0x800) {
270		/* 110***** 10****** */
271		kbd_put_queue(tty, 0xc0 | (c >> 6));
272		kbd_put_queue(tty, 0x80 | (c & 0x3f));
273	} else {
274		/* 1110**** 10****** 10****** */
275		kbd_put_queue(tty, 0xe0 | (c >> 12));
276		kbd_put_queue(tty, 0x80 | ((c >> 6) & 0x3f));
277		kbd_put_queue(tty, 0x80 | (c & 0x3f));
278	}
279}
280
281/*
282 * Process keycode.
283 */
284void
285kbd_keycode(struct kbd_data *kbd, unsigned int keycode)
286{
287	unsigned short keysym;
288	unsigned char type, value;
289
290	if (!kbd || !kbd->tty)
291		return;
292
293	if (keycode >= 384)
294		keysym = kbd->key_maps[5][keycode - 384];
295	else if (keycode >= 256)
296		keysym = kbd->key_maps[4][keycode - 256];
297	else if (keycode >= 128)
298		keysym = kbd->key_maps[1][keycode - 128];
299	else
300		keysym = kbd->key_maps[0][keycode];
301
302	type = KTYP(keysym);
303	if (type >= 0xf0) {
304		type -= 0xf0;
305		if (type == KT_LETTER)
306			type = KT_LATIN;
307		value = KVAL(keysym);
308#ifdef CONFIG_MAGIC_SYSRQ	       /* Handle the SysRq Hack */
309		if (kbd->sysrq) {
310			if (kbd->sysrq == K(KT_LATIN, '-')) {
311				kbd->sysrq = 0;
312				handle_sysrq(value, 0, kbd->tty);
313				return;
314			}
315			if (value == '-') {
316				kbd->sysrq = K(KT_LATIN, '-');
317				return;
318			}
319			/* Incomplete sysrq sequence. */
320			(*k_handler[KTYP(kbd->sysrq)])(kbd, KVAL(kbd->sysrq));
321			kbd->sysrq = 0;
322		} else if ((type == KT_LATIN && value == '^') ||
323			   (type == KT_DEAD && ret_diacr[value] == '^')) {
324			kbd->sysrq = K(type, value);
325			return;
326		}
327#endif
328		(*k_handler[type])(kbd, value);
329	} else
330		to_utf8(kbd->tty, keysym);
331}
332
333/*
334 * Ioctl stuff.
335 */
336static int
337do_kdsk_ioctl(struct kbd_data *kbd, struct kbentry __user *user_kbe,
338	      int cmd, int perm)
339{
340	struct kbentry tmp;
341	ushort *key_map, val, ov;
342
343	if (copy_from_user(&tmp, user_kbe, sizeof(struct kbentry)))
344		return -EFAULT;
345#if NR_KEYS < 256
346	if (tmp.kb_index >= NR_KEYS)
347		return -EINVAL;
348#endif
349#if MAX_NR_KEYMAPS < 256
350	if (tmp.kb_table >= MAX_NR_KEYMAPS)
351		return -EINVAL;
352#endif
353
354	switch (cmd) {
355	case KDGKBENT:
356		key_map = kbd->key_maps[tmp.kb_table];
357		if (key_map) {
358		    val = U(key_map[tmp.kb_index]);
359		    if (KTYP(val) >= KBD_NR_TYPES)
360			val = K_HOLE;
361		} else
362		    val = (tmp.kb_index ? K_HOLE : K_NOSUCHMAP);
363		return put_user(val, &user_kbe->kb_value);
364	case KDSKBENT:
365		if (!perm)
366			return -EPERM;
367		if (!tmp.kb_index && tmp.kb_value == K_NOSUCHMAP) {
368			/* disallocate map */
369			key_map = kbd->key_maps[tmp.kb_table];
370			if (key_map) {
371			    kbd->key_maps[tmp.kb_table] = 0;
372			    kfree(key_map);
373			}
374			break;
375		}
376
377		if (KTYP(tmp.kb_value) >= KBD_NR_TYPES)
378			return -EINVAL;
379		if (KVAL(tmp.kb_value) > kbd_max_vals[KTYP(tmp.kb_value)])
380			return -EINVAL;
381
382		if (!(key_map = kbd->key_maps[tmp.kb_table])) {
383			int j;
384
385			key_map = (ushort *) kmalloc(sizeof(plain_map),
386						     GFP_KERNEL);
387			if (!key_map)
388				return -ENOMEM;
389			kbd->key_maps[tmp.kb_table] = key_map;
390			for (j = 0; j < NR_KEYS; j++)
391				key_map[j] = U(K_HOLE);
392		}
393		ov = U(key_map[tmp.kb_index]);
394		if (tmp.kb_value == ov)
395			break;	/* nothing to do */
396		/*
397		 * Attention Key.
398		 */
399		if (((ov == K_SAK) || (tmp.kb_value == K_SAK)) &&
400		    !capable(CAP_SYS_ADMIN))
401			return -EPERM;
402		key_map[tmp.kb_index] = U(tmp.kb_value);
403		break;
404	}
405	return 0;
406}
407
408static int
409do_kdgkb_ioctl(struct kbd_data *kbd, struct kbsentry __user *u_kbs,
410	       int cmd, int perm)
411{
412	unsigned char kb_func;
413	char *p;
414	int len;
415
416	/* Get u_kbs->kb_func. */
417	if (get_user(kb_func, &u_kbs->kb_func))
418		return -EFAULT;
419#if MAX_NR_FUNC < 256
420	if (kb_func >= MAX_NR_FUNC)
421		return -EINVAL;
422#endif
423
424	switch (cmd) {
425	case KDGKBSENT:
426		p = kbd->func_table[kb_func];
427		if (p) {
428			len = strlen(p);
429			if (len >= sizeof(u_kbs->kb_string))
430				len = sizeof(u_kbs->kb_string) - 1;
431			if (copy_to_user(u_kbs->kb_string, p, len))
432				return -EFAULT;
433		} else
434			len = 0;
435		if (put_user('\0', u_kbs->kb_string + len))
436			return -EFAULT;
437		break;
438	case KDSKBSENT:
439		if (!perm)
440			return -EPERM;
441		len = strnlen_user(u_kbs->kb_string,
442				   sizeof(u_kbs->kb_string) - 1);
443		if (!len)
444			return -EFAULT;
445		if (len > sizeof(u_kbs->kb_string) - 1)
446			return -EINVAL;
447		p = kmalloc(len + 1, 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		kfree(kbd->func_table[kb_func]);
456		kbd->func_table[kb_func] = p;
457		break;
458	}
459	return 0;
460}
461
462int
463kbd_ioctl(struct kbd_data *kbd, struct file *file,
464	  unsigned int cmd, unsigned long arg)
465{
466	struct kbdiacrs __user *a;
467	void __user *argp;
468	int ct, perm;
469
470	argp = (void __user *)arg;
471
472	/*
473	 * To have permissions to do most of the vt ioctls, we either have
474	 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
475	 */
476	perm = current->signal->tty == kbd->tty || capable(CAP_SYS_TTY_CONFIG);
477	switch (cmd) {
478	case KDGKBTYPE:
479		return put_user(KB_101, (char __user *)argp);
480	case KDGKBENT:
481	case KDSKBENT:
482		return do_kdsk_ioctl(kbd, argp, cmd, perm);
483	case KDGKBSENT:
484	case KDSKBSENT:
485		return do_kdgkb_ioctl(kbd, argp, cmd, perm);
486	case KDGKBDIACR:
487		a = argp;
488
489		if (put_user(kbd->accent_table_size, &a->kb_cnt))
490			return -EFAULT;
491		ct = kbd->accent_table_size;
492		if (copy_to_user(a->kbdiacr, kbd->accent_table,
493				 ct * sizeof(struct kbdiacr)))
494			return -EFAULT;
495		return 0;
496	case KDSKBDIACR:
497		a = argp;
498		if (!perm)
499			return -EPERM;
500		if (get_user(ct, &a->kb_cnt))
501			return -EFAULT;
502		if (ct >= MAX_DIACR)
503			return -EINVAL;
504		kbd->accent_table_size = ct;
505		if (copy_from_user(kbd->accent_table, a->kbdiacr,
506				   ct * sizeof(struct kbdiacr)))
507			return -EFAULT;
508		return 0;
509	default:
510		return -ENOIOCTLCMD;
511	}
512}
513
514EXPORT_SYMBOL(kbd_ioctl);
515EXPORT_SYMBOL(kbd_ascebc);
516EXPORT_SYMBOL(kbd_free);
517EXPORT_SYMBOL(kbd_alloc);
518EXPORT_SYMBOL(kbd_keycode);
519