drivers/s390/char/keyboard.c

   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                 kfree(kbd->func_table[i]);
 103         kfree(kbd->func_table);
 104 out_maps:
 105         for (i = 0; i < ARRAY_SIZE(key_maps); i++)
 106                 kfree(kbd->key_maps[i]);
 107         kfree(kbd->key_maps);
 108 out_kbd:
 109         kfree(kbd);
 110 out:
 111         return 0;
 112 }
 113
 114 void
 115 kbd_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  */
 133 void
 134 kbd_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  */
 159 void
 160 kbd_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  */
 189 static unsigned char
 190 handle_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  */
 213 static void
 214 k_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  */
 223 static void
 224 k_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  */
 234 static void
 235 k_ignore(struct kbd_data *kbd, unsigned char value)
 236 {
 237 }
 238
 239 /*
 240  * Function key handler.
 241  */
 242 static void
 243 k_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
 249 static void
 250 k_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  */
 263 static void
 264 to_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  */
 284 void
 285 kbd_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  */
 336 static int
 337 do_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
 408 static int
 409 do_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                 p = kmalloc(len, GFP_KERNEL);
 444                 if (!p)
 445                         return -ENOMEM;
 446                 if (copy_from_user(p, u_kbs->kb_string, len)) {
 447                         kfree(p);
 448                         return -EFAULT;
 449                 }
 450                 p[len] = 0;
 451                 kfree(kbd->func_table[kb_func]);
 452                 kbd->func_table[kb_func] = p;
 453                 break;
 454         }
 455         return 0;
 456 }
 457
 458 int
 459 kbd_ioctl(struct kbd_data *kbd, struct file *file,
 460           unsigned int cmd, unsigned long arg)
 461 {
 462         struct kbdiacrs __user *a;
 463         void __user *argp;
 464         int ct, perm;
 465
 466         argp = (void __user *)arg;
 467
 468         /*
 469          * To have permissions to do most of the vt ioctls, we either have
 470          * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
 471          */
 472         perm = current->signal->tty == kbd->tty || capable(CAP_SYS_TTY_CONFIG);
 473         switch (cmd) {
 474         case KDGKBTYPE:
 475                 return put_user(KB_101, (char __user *)argp);
 476         case KDGKBENT:
 477         case KDSKBENT:
 478                 return do_kdsk_ioctl(kbd, argp, cmd, perm);
 479         case KDGKBSENT:
 480         case KDSKBSENT:
 481                 return do_kdgkb_ioctl(kbd, argp, cmd, perm);
 482         case KDGKBDIACR:
 483                 a = argp;
 484
 485                 if (put_user(kbd->accent_table_size, &a->kb_cnt))
 486                         return -EFAULT;
 487                 ct = kbd->accent_table_size;
 488                 if (copy_to_user(a->kbdiacr, kbd->accent_table,
 489                                  ct * sizeof(struct kbdiacr)))
 490                         return -EFAULT;
 491                 return 0;
 492         case KDSKBDIACR:
 493                 a = argp;
 494                 if (!perm)
 495                         return -EPERM;
 496                 if (get_user(ct, &a->kb_cnt))
 497                         return -EFAULT;
 498                 if (ct >= MAX_DIACR)
 499                         return -EINVAL;
 500                 kbd->accent_table_size = ct;
 501                 if (copy_from_user(kbd->accent_table, a->kbdiacr,
 502                                    ct * sizeof(struct kbdiacr)))
 503                         return -EFAULT;
 504                 return 0;
 505         default:
 506                 return -ENOIOCTLCMD;
 507         }
 508 }
 509
 510 EXPORT_SYMBOL(kbd_ioctl);
 511 EXPORT_SYMBOL(kbd_ascebc);
 512 EXPORT_SYMBOL(kbd_free);
 513 EXPORT_SYMBOL(kbd_alloc);
 514 EXPORT_SYMBOL(kbd_keycode);