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                 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);