keyboard.c revision 5cbded585d129d0226cb48ac4202b253c781be26 
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/kbd_kern.h>
15#include <linux/kbd_diacr.h>
16#include <asm/uaccess.h>
17
18#include "keyboard.h"
19
20/*
21 * Handler Tables.
22 */
23#define K_HANDLERS\
24	k_self,		k_fn,		k_spec,		k_ignore,\
25	k_dead,		k_ignore,	k_ignore,	k_ignore,\
26	k_ignore,	k_ignore,	k_ignore,	k_ignore,\
27	k_ignore,	k_ignore,	k_ignore,	k_ignore
28
29typedef void (k_handler_fn)(struct kbd_data *, unsigned char);
30static k_handler_fn K_HANDLERS;
31static k_handler_fn *k_handler[16] = { K_HANDLERS };
32
33/* maximum values each key_handler can handle */
34static const int kbd_max_vals[] = {
35	255, ARRAY_SIZE(func_table) - 1, NR_FN_HANDLER - 1, 0,
36	NR_DEAD - 1, 0, 0, 0, 0, 0, 0, 0, 0, 0
37};
38static const int KBD_NR_TYPES = ARRAY_SIZE(kbd_max_vals);
39
40static unsigned char ret_diacr[NR_DEAD] = {
41	'`', '\'', '^', '~', '"', ','
42};
43
44/*
45 * Alloc/free of kbd_data structures.
46 */
47struct kbd_data *
48kbd_alloc(void) {
49	struct kbd_data *kbd;
50	int i, len;
51
52	kbd = kzalloc(sizeof(struct kbd_data), GFP_KERNEL);
53	if (!kbd)
54		goto out;
55	kbd->key_maps = kzalloc(sizeof(key_maps), GFP_KERNEL);
56	if (!kbd->key_maps)
57		goto out_kbd;
58	for (i = 0; i < ARRAY_SIZE(key_maps); i++) {
59		if (key_maps[i]) {
60			kbd->key_maps[i] =
61				kmalloc(sizeof(u_short)*NR_KEYS, GFP_KERNEL);
62			if (!kbd->key_maps[i])
63				goto out_maps;
64			memcpy(kbd->key_maps[i], key_maps[i],
65			       sizeof(u_short)*NR_KEYS);
66		}
67	}
68	kbd->func_table = kzalloc(sizeof(func_table), GFP_KERNEL);
69	if (!kbd->func_table)
70		goto out_maps;
71	for (i = 0; i < ARRAY_SIZE(func_table); i++) {
72		if (func_table[i]) {
73			len = strlen(func_table[i]) + 1;
74			kbd->func_table[i] = kmalloc(len, GFP_KERNEL);
75			if (!kbd->func_table[i])
76				goto out_func;
77			memcpy(kbd->func_table[i], func_table[i], len);
78		}
79	}
80	kbd->fn_handler =
81		kzalloc(sizeof(fn_handler_fn *) * NR_FN_HANDLER, GFP_KERNEL);
82	if (!kbd->fn_handler)
83		goto out_func;
84	kbd->accent_table =
85		kmalloc(sizeof(struct kbdiacr)*MAX_DIACR, GFP_KERNEL);
86	if (!kbd->accent_table)
87		goto out_fn_handler;
88	memcpy(kbd->accent_table, accent_table,
89	       sizeof(struct kbdiacr)*MAX_DIACR);
90	kbd->accent_table_size = accent_table_size;
91	return kbd;
92
93out_fn_handler:
94	kfree(kbd->fn_handler);
95out_func:
96	for (i = 0; i < ARRAY_SIZE(func_table); i++)
97		kfree(kbd->func_table[i]);
98	kfree(kbd->func_table);
99out_maps:
100	for (i = 0; i < ARRAY_SIZE(key_maps); i++)
101		kfree(kbd->key_maps[i]);
102	kfree(kbd->key_maps);
103out_kbd:
104	kfree(kbd);
105out:
106	return NULL;
107}
108
109void
110kbd_free(struct kbd_data *kbd)
111{
112	int i;
113
114	kfree(kbd->accent_table);
115	kfree(kbd->fn_handler);
116	for (i = 0; i < ARRAY_SIZE(func_table); i++)
117		kfree(kbd->func_table[i]);
118	kfree(kbd->func_table);
119	for (i = 0; i < ARRAY_SIZE(key_maps); i++)
120		kfree(kbd->key_maps[i]);
121	kfree(kbd->key_maps);
122	kfree(kbd);
123}
124
125/*
126 * Generate ascii -> ebcdic translation table from kbd_data.
127 */
128void
129kbd_ascebc(struct kbd_data *kbd, unsigned char *ascebc)
130{
131	unsigned short *keymap, keysym;
132	int i, j, k;
133
134	memset(ascebc, 0x40, 256);
135	for (i = 0; i < ARRAY_SIZE(key_maps); i++) {
136		keymap = kbd->key_maps[i];
137		if (!keymap)
138			continue;
139		for (j = 0; j < NR_KEYS; j++) {
140			k = ((i & 1) << 7) + j;
141			keysym = keymap[j];
142			if (KTYP(keysym) == (KT_LATIN | 0xf0) ||
143			    KTYP(keysym) == (KT_LETTER | 0xf0))
144				ascebc[KVAL(keysym)] = k;
145			else if (KTYP(keysym) == (KT_DEAD | 0xf0))
146				ascebc[ret_diacr[KVAL(keysym)]] = k;
147		}
148	}
149}
150
151/*
152 * Generate ebcdic -> ascii translation table from kbd_data.
153 */
154void
155kbd_ebcasc(struct kbd_data *kbd, unsigned char *ebcasc)
156{
157	unsigned short *keymap, keysym;
158	int i, j, k;
159
160	memset(ebcasc, ' ', 256);
161	for (i = 0; i < ARRAY_SIZE(key_maps); i++) {
162		keymap = kbd->key_maps[i];
163		if (!keymap)
164			continue;
165		for (j = 0; j < NR_KEYS; j++) {
166			keysym = keymap[j];
167			k = ((i & 1) << 7) + j;
168			if (KTYP(keysym) == (KT_LATIN | 0xf0) ||
169			    KTYP(keysym) == (KT_LETTER | 0xf0))
170				ebcasc[k] = KVAL(keysym);
171			else if (KTYP(keysym) == (KT_DEAD | 0xf0))
172				ebcasc[k] = ret_diacr[KVAL(keysym)];
173		}
174	}
175}
176
177/*
178 * We have a combining character DIACR here, followed by the character CH.
179 * If the combination occurs in the table, return the corresponding value.
180 * Otherwise, if CH is a space or equals DIACR, return DIACR.
181 * Otherwise, conclude that DIACR was not combining after all,
182 * queue it and return CH.
183 */
184static unsigned char
185handle_diacr(struct kbd_data *kbd, unsigned char ch)
186{
187	int i, d;
188
189	d = kbd->diacr;
190	kbd->diacr = 0;
191
192	for (i = 0; i < kbd->accent_table_size; i++) {
193		if (kbd->accent_table[i].diacr == d &&
194		    kbd->accent_table[i].base == ch)
195			return kbd->accent_table[i].result;
196	}
197
198	if (ch == ' ' || ch == d)
199		return d;
200
201	kbd_put_queue(kbd->tty, d);
202	return ch;
203}
204
205/*
206 * Handle dead key.
207 */
208static void
209k_dead(struct kbd_data *kbd, unsigned char value)
210{
211	value = ret_diacr[value];
212	kbd->diacr = (kbd->diacr ? handle_diacr(kbd, value) : value);
213}
214
215/*
216 * Normal character handler.
217 */
218static void
219k_self(struct kbd_data *kbd, unsigned char value)
220{
221	if (kbd->diacr)
222		value = handle_diacr(kbd, value);
223	kbd_put_queue(kbd->tty, value);
224}
225
226/*
227 * Special key handlers
228 */
229static void
230k_ignore(struct kbd_data *kbd, unsigned char value)
231{
232}
233
234/*
235 * Function key handler.
236 */
237static void
238k_fn(struct kbd_data *kbd, unsigned char value)
239{
240	if (kbd->func_table[value])
241		kbd_puts_queue(kbd->tty, kbd->func_table[value]);
242}
243
244static void
245k_spec(struct kbd_data *kbd, unsigned char value)
246{
247	if (value >= NR_FN_HANDLER)
248		return;
249	if (kbd->fn_handler[value])
250		kbd->fn_handler[value](kbd);
251}
252
253/*
254 * Put utf8 character to tty flip buffer.
255 * UTF-8 is defined for words of up to 31 bits,
256 * but we need only 16 bits here
257 */
258static void
259to_utf8(struct tty_struct *tty, ushort c)
260{
261	if (c < 0x80)
262		/*  0******* */
263		kbd_put_queue(tty, c);
264	else if (c < 0x800) {
265		/* 110***** 10****** */
266		kbd_put_queue(tty, 0xc0 | (c >> 6));
267		kbd_put_queue(tty, 0x80 | (c & 0x3f));
268	} else {
269		/* 1110**** 10****** 10****** */
270		kbd_put_queue(tty, 0xe0 | (c >> 12));
271		kbd_put_queue(tty, 0x80 | ((c >> 6) & 0x3f));
272		kbd_put_queue(tty, 0x80 | (c & 0x3f));
273	}
274}
275
276/*
277 * Process keycode.
278 */
279void
280kbd_keycode(struct kbd_data *kbd, unsigned int keycode)
281{
282	unsigned short keysym;
283	unsigned char type, value;
284
285	if (!kbd || !kbd->tty)
286		return;
287
288	if (keycode >= 384)
289		keysym = kbd->key_maps[5][keycode - 384];
290	else if (keycode >= 256)
291		keysym = kbd->key_maps[4][keycode - 256];
292	else if (keycode >= 128)
293		keysym = kbd->key_maps[1][keycode - 128];
294	else
295		keysym = kbd->key_maps[0][keycode];
296
297	type = KTYP(keysym);
298	if (type >= 0xf0) {
299		type -= 0xf0;
300		if (type == KT_LETTER)
301			type = KT_LATIN;
302		value = KVAL(keysym);
303#ifdef CONFIG_MAGIC_SYSRQ	       /* Handle the SysRq Hack */
304		if (kbd->sysrq) {
305			if (kbd->sysrq == K(KT_LATIN, '-')) {
306				kbd->sysrq = 0;
307				handle_sysrq(value, kbd->tty);
308				return;
309			}
310			if (value == '-') {
311				kbd->sysrq = K(KT_LATIN, '-');
312				return;
313			}
314			/* Incomplete sysrq sequence. */
315			(*k_handler[KTYP(kbd->sysrq)])(kbd, KVAL(kbd->sysrq));
316			kbd->sysrq = 0;
317		} else if ((type == KT_LATIN && value == '^') ||
318			   (type == KT_DEAD && ret_diacr[value] == '^')) {
319			kbd->sysrq = K(type, value);
320			return;
321		}
322#endif
323		(*k_handler[type])(kbd, value);
324	} else
325		to_utf8(kbd->tty, keysym);
326}
327
328/*
329 * Ioctl stuff.
330 */
331static int
332do_kdsk_ioctl(struct kbd_data *kbd, struct kbentry __user *user_kbe,
333	      int cmd, int perm)
334{
335	struct kbentry tmp;
336	ushort *key_map, val, ov;
337
338	if (copy_from_user(&tmp, user_kbe, sizeof(struct kbentry)))
339		return -EFAULT;
340#if NR_KEYS < 256
341	if (tmp.kb_index >= NR_KEYS)
342		return -EINVAL;
343#endif
344#if MAX_NR_KEYMAPS < 256
345	if (tmp.kb_table >= MAX_NR_KEYMAPS)
346		return -EINVAL;
347#endif
348
349	switch (cmd) {
350	case KDGKBENT:
351		key_map = kbd->key_maps[tmp.kb_table];
352		if (key_map) {
353		    val = U(key_map[tmp.kb_index]);
354		    if (KTYP(val) >= KBD_NR_TYPES)
355			val = K_HOLE;
356		} else
357		    val = (tmp.kb_index ? K_HOLE : K_NOSUCHMAP);
358		return put_user(val, &user_kbe->kb_value);
359	case KDSKBENT:
360		if (!perm)
361			return -EPERM;
362		if (!tmp.kb_index && tmp.kb_value == K_NOSUCHMAP) {
363			/* disallocate map */
364			key_map = kbd->key_maps[tmp.kb_table];
365			if (key_map) {
366			    kbd->key_maps[tmp.kb_table] = NULL;
367			    kfree(key_map);
368			}
369			break;
370		}
371
372		if (KTYP(tmp.kb_value) >= KBD_NR_TYPES)
373			return -EINVAL;
374		if (KVAL(tmp.kb_value) > kbd_max_vals[KTYP(tmp.kb_value)])
375			return -EINVAL;
376
377		if (!(key_map = kbd->key_maps[tmp.kb_table])) {
378			int j;
379
380			key_map = kmalloc(sizeof(plain_map),
381						     GFP_KERNEL);
382			if (!key_map)
383				return -ENOMEM;
384			kbd->key_maps[tmp.kb_table] = key_map;
385			for (j = 0; j < NR_KEYS; j++)
386				key_map[j] = U(K_HOLE);
387		}
388		ov = U(key_map[tmp.kb_index]);
389		if (tmp.kb_value == ov)
390			break;	/* nothing to do */
391		/*
392		 * Attention Key.
393		 */
394		if (((ov == K_SAK) || (tmp.kb_value == K_SAK)) &&
395		    !capable(CAP_SYS_ADMIN))
396			return -EPERM;
397		key_map[tmp.kb_index] = U(tmp.kb_value);
398		break;
399	}
400	return 0;
401}
402
403static int
404do_kdgkb_ioctl(struct kbd_data *kbd, struct kbsentry __user *u_kbs,
405	       int cmd, int perm)
406{
407	unsigned char kb_func;
408	char *p;
409	int len;
410
411	/* Get u_kbs->kb_func. */
412	if (get_user(kb_func, &u_kbs->kb_func))
413		return -EFAULT;
414#if MAX_NR_FUNC < 256
415	if (kb_func >= MAX_NR_FUNC)
416		return -EINVAL;
417#endif
418
419	switch (cmd) {
420	case KDGKBSENT:
421		p = kbd->func_table[kb_func];
422		if (p) {
423			len = strlen(p);
424			if (len >= sizeof(u_kbs->kb_string))
425				len = sizeof(u_kbs->kb_string) - 1;
426			if (copy_to_user(u_kbs->kb_string, p, len))
427				return -EFAULT;
428		} else
429			len = 0;
430		if (put_user('\0', u_kbs->kb_string + len))
431			return -EFAULT;
432		break;
433	case KDSKBSENT:
434		if (!perm)
435			return -EPERM;
436		len = strnlen_user(u_kbs->kb_string,
437				   sizeof(u_kbs->kb_string) - 1);
438		if (!len)
439			return -EFAULT;
440		if (len > sizeof(u_kbs->kb_string) - 1)
441			return -EINVAL;
442		p = kmalloc(len + 1, GFP_KERNEL);
443		if (!p)
444			return -ENOMEM;
445		if (copy_from_user(p, u_kbs->kb_string, len)) {
446			kfree(p);
447			return -EFAULT;
448		}
449		p[len] = 0;
450		kfree(kbd->func_table[kb_func]);
451		kbd->func_table[kb_func] = p;
452		break;
453	}
454	return 0;
455}
456
457int
458kbd_ioctl(struct kbd_data *kbd, struct file *file,
459	  unsigned int cmd, unsigned long arg)
460{
461	struct kbdiacrs __user *a;
462	void __user *argp;
463	int ct, perm;
464
465	argp = (void __user *)arg;
466
467	/*
468	 * To have permissions to do most of the vt ioctls, we either have
469	 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
470	 */
471	perm = current->signal->tty == kbd->tty || capable(CAP_SYS_TTY_CONFIG);
472	switch (cmd) {
473	case KDGKBTYPE:
474		return put_user(KB_101, (char __user *)argp);
475	case KDGKBENT:
476	case KDSKBENT:
477		return do_kdsk_ioctl(kbd, argp, cmd, perm);
478	case KDGKBSENT:
479	case KDSKBSENT:
480		return do_kdgkb_ioctl(kbd, argp, cmd, perm);
481	case KDGKBDIACR:
482		a = argp;
483
484		if (put_user(kbd->accent_table_size, &a->kb_cnt))
485			return -EFAULT;
486		ct = kbd->accent_table_size;
487		if (copy_to_user(a->kbdiacr, kbd->accent_table,
488				 ct * sizeof(struct kbdiacr)))
489			return -EFAULT;
490		return 0;
491	case KDSKBDIACR:
492		a = argp;
493		if (!perm)
494			return -EPERM;
495		if (get_user(ct, &a->kb_cnt))
496			return -EFAULT;
497		if (ct >= MAX_DIACR)
498			return -EINVAL;
499		kbd->accent_table_size = ct;
500		if (copy_from_user(kbd->accent_table, a->kbdiacr,
501				   ct * sizeof(struct kbdiacr)))
502			return -EFAULT;
503		return 0;
504	default:
505		return -ENOIOCTLCMD;
506	}
507}
508
509EXPORT_SYMBOL(kbd_ioctl);
510EXPORT_SYMBOL(kbd_ascebc);
511EXPORT_SYMBOL(kbd_free);
512EXPORT_SYMBOL(kbd_alloc);
513EXPORT_SYMBOL(kbd_keycode);
514