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/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
  29 typedef void (k_handler_fn)(struct kbd_data *, unsigned char);
  30 static k_handler_fn K_HANDLERS;
  31 static k_handler_fn *k_handler[16] = { K_HANDLERS };
  32
  33 /* maximum values each key_handler can handle */
  34 static 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 };
  38 static const int KBD_NR_TYPES = ARRAY_SIZE(kbd_max_vals);
  39
  40 static unsigned char ret_diacr[NR_DEAD] = {
  41         '`', '\'', '^', '~', '"', ','
  42 };
  43
  44 /*
  45  * Alloc/free of kbd_data structures.
  46  */
  47 struct kbd_data *
  48 kbd_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
  93 out_fn_handler:
  94         kfree(kbd->fn_handler);
  95 out_func:
  96         for (i = 0; i < ARRAY_SIZE(func_table); i++)
  97                 kfree(kbd->func_table[i]);
  98         kfree(kbd->func_table);
  99 out_maps:
 100         for (i = 0; i < ARRAY_SIZE(key_maps); i++)
 101                 kfree(kbd->key_maps[i]);
 102         kfree(kbd->key_maps);
 103 out_kbd:
 104         kfree(kbd);
 105 out:
 106         return NULL;
 107 }
 108
 109 void
 110 kbd_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  */
 128 void
 129 kbd_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  */
 154 void
 155 kbd_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  */
 184 static unsigned char
 185 handle_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  */
 208 static void
 209 k_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  */
 218 static void
 219 k_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  */
 229 static void
 230 k_ignore(struct kbd_data *kbd, unsigned char value)
 231 {
 232 }
 233
 234 /*
 235  * Function key handler.
 236  */
 237 static void
 238 k_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
 244 static void
 245 k_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  */
 258 static void
 259 to_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  */
 279 void
 280 kbd_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  */
 331 static int
 332 do_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 = (ushort *) 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
 403 static int
 404 do_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
 457 int
 458 kbd_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
 509 EXPORT_SYMBOL(kbd_ioctl);
 510 EXPORT_SYMBOL(kbd_ascebc);
 511 EXPORT_SYMBOL(kbd_free);
 512 EXPORT_SYMBOL(kbd_alloc);
 513 EXPORT_SYMBOL(kbd_keycode);