root/drivers/s390/char/keyboard.c

DEFINITIONS

1. kbd_alloc
2. kbd_free
3. kbd_ascebc
4. kbd_ebcasc
5. handle_diacr
6. k_dead
7. k_self
8. k_ignore
9. k_fn
10. k_spec
11. to_utf8
12. kbd_keycode
13. do_kdsk_ioctl
14. do_kdgkb_ioctl
15. kbd_ioctl

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *    ebcdic keycode functions for s390 console drivers
   4  *
   5  *  S390 version
   6  *    Copyright IBM Corp. 2003
   7  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
   8  */
   9 
  10 #include <linux/module.h>
  11 #include <linux/sched/signal.h>
  12 #include <linux/slab.h>
  13 #include <linux/sysrq.h>
  14 
  15 #include <linux/consolemap.h>
  16 #include <linux/kbd_kern.h>
  17 #include <linux/kbd_diacr.h>
  18 #include <linux/uaccess.h>
  19 
  20 #include "keyboard.h"
  21 
  22 /*
  23  * Handler Tables.
  24  */
  25 #define K_HANDLERS\
  26         k_self,         k_fn,           k_spec,         k_ignore,\
  27         k_dead,         k_ignore,       k_ignore,       k_ignore,\
  28         k_ignore,       k_ignore,       k_ignore,       k_ignore,\
  29         k_ignore,       k_ignore,       k_ignore,       k_ignore
  30 
  31 typedef void (k_handler_fn)(struct kbd_data *, unsigned char);
  32 static k_handler_fn K_HANDLERS;
  33 static k_handler_fn *k_handler[16] = { K_HANDLERS };
  34 
  35 /* maximum values each key_handler can handle */
  36 static const int kbd_max_vals[] = {
  37         255, ARRAY_SIZE(func_table) - 1, NR_FN_HANDLER - 1, 0,
  38         NR_DEAD - 1, 0, 0, 0, 0, 0, 0, 0, 0, 0
  39 };
  40 static const int KBD_NR_TYPES = ARRAY_SIZE(kbd_max_vals);
  41 
  42 static const unsigned char ret_diacr[NR_DEAD] = {
  43         '`',    /* dead_grave */
  44         '\'',   /* dead_acute */
  45         '^',    /* dead_circumflex */
  46         '~',    /* dead_tilda */
  47         '"',    /* dead_diaeresis */
  48         ',',    /* dead_cedilla */
  49         '_',    /* dead_macron */
  50         'U',    /* dead_breve */
  51         '.',    /* dead_abovedot */
  52         '*',    /* dead_abovering */
  53         '=',    /* dead_doubleacute */
  54         'c',    /* dead_caron */
  55         'k',    /* dead_ogonek */
  56         'i',    /* dead_iota */
  57         '#',    /* dead_voiced_sound */
  58         'o',    /* dead_semivoiced_sound */
  59         '!',    /* dead_belowdot */
  60         '?',    /* dead_hook */
  61         '+',    /* dead_horn */
  62         '-',    /* dead_stroke */
  63         ')',    /* dead_abovecomma */
  64         '(',    /* dead_abovereversedcomma */
  65         ':',    /* dead_doublegrave */
  66         'n',    /* dead_invertedbreve */
  67         ';',    /* dead_belowcomma */
  68         '$',    /* dead_currency */
  69         '@',    /* dead_greek */
  70 };
  71 
  72 /*
  73  * Alloc/free of kbd_data structures.
  74  */
  75 struct kbd_data *
  76 kbd_alloc(void) {
  77         struct kbd_data *kbd;
  78         int i;
  79 
  80         kbd = kzalloc(sizeof(struct kbd_data), GFP_KERNEL);
  81         if (!kbd)
  82                 goto out;
  83         kbd->key_maps = kzalloc(sizeof(ebc_key_maps), GFP_KERNEL);
  84         if (!kbd->key_maps)
  85                 goto out_kbd;
  86         for (i = 0; i < ARRAY_SIZE(ebc_key_maps); i++) {
  87                 if (ebc_key_maps[i]) {
  88                         kbd->key_maps[i] = kmemdup(ebc_key_maps[i],
  89                                                    sizeof(u_short) * NR_KEYS,
  90                                                    GFP_KERNEL);
  91                         if (!kbd->key_maps[i])
  92                                 goto out_maps;
  93                 }
  94         }
  95         kbd->func_table = kzalloc(sizeof(ebc_func_table), GFP_KERNEL);
  96         if (!kbd->func_table)
  97                 goto out_maps;
  98         for (i = 0; i < ARRAY_SIZE(ebc_func_table); i++) {
  99                 if (ebc_func_table[i]) {
 100                         kbd->func_table[i] = kstrdup(ebc_func_table[i],
 101                                                      GFP_KERNEL);
 102                         if (!kbd->func_table[i])
 103                                 goto out_func;
 104                 }
 105         }
 106         kbd->fn_handler =
 107                 kcalloc(NR_FN_HANDLER, sizeof(fn_handler_fn *), GFP_KERNEL);
 108         if (!kbd->fn_handler)
 109                 goto out_func;
 110         kbd->accent_table = kmemdup(ebc_accent_table,
 111                                     sizeof(struct kbdiacruc) * MAX_DIACR,
 112                                     GFP_KERNEL);
 113         if (!kbd->accent_table)
 114                 goto out_fn_handler;
 115         kbd->accent_table_size = ebc_accent_table_size;
 116         return kbd;
 117 
 118 out_fn_handler:
 119         kfree(kbd->fn_handler);
 120 out_func:
 121         for (i = 0; i < ARRAY_SIZE(ebc_func_table); i++)
 122                 kfree(kbd->func_table[i]);
 123         kfree(kbd->func_table);
 124 out_maps:
 125         for (i = 0; i < ARRAY_SIZE(ebc_key_maps); i++)
 126                 kfree(kbd->key_maps[i]);
 127         kfree(kbd->key_maps);
 128 out_kbd:
 129         kfree(kbd);
 130 out:
 131         return NULL;
 132 }
 133 
 134 void
 135 kbd_free(struct kbd_data *kbd)
 136 {
 137         int i;
 138 
 139         kfree(kbd->accent_table);
 140         kfree(kbd->fn_handler);
 141         for (i = 0; i < ARRAY_SIZE(ebc_func_table); i++)
 142                 kfree(kbd->func_table[i]);
 143         kfree(kbd->func_table);
 144         for (i = 0; i < ARRAY_SIZE(ebc_key_maps); i++)
 145                 kfree(kbd->key_maps[i]);
 146         kfree(kbd->key_maps);
 147         kfree(kbd);
 148 }
 149 
 150 /*
 151  * Generate ascii -> ebcdic translation table from kbd_data.
 152  */
 153 void
 154 kbd_ascebc(struct kbd_data *kbd, unsigned char *ascebc)
 155 {
 156         unsigned short *keymap, keysym;
 157         int i, j, k;
 158 
 159         memset(ascebc, 0x40, 256);
 160         for (i = 0; i < ARRAY_SIZE(ebc_key_maps); i++) {
 161                 keymap = kbd->key_maps[i];
 162                 if (!keymap)
 163                         continue;
 164                 for (j = 0; j < NR_KEYS; j++) {
 165                         k = ((i & 1) << 7) + j;
 166                         keysym = keymap[j];
 167                         if (KTYP(keysym) == (KT_LATIN | 0xf0) ||
 168                             KTYP(keysym) == (KT_LETTER | 0xf0))
 169                                 ascebc[KVAL(keysym)] = k;
 170                         else if (KTYP(keysym) == (KT_DEAD | 0xf0))
 171                                 ascebc[ret_diacr[KVAL(keysym)]] = k;
 172                 }
 173         }
 174 }
 175 
 176 #if 0
 177 /*
 178  * Generate ebcdic -> ascii translation table from kbd_data.
 179  */
 180 void
 181 kbd_ebcasc(struct kbd_data *kbd, unsigned char *ebcasc)
 182 {
 183         unsigned short *keymap, keysym;
 184         int i, j, k;
 185 
 186         memset(ebcasc, ' ', 256);
 187         for (i = 0; i < ARRAY_SIZE(ebc_key_maps); i++) {
 188                 keymap = kbd->key_maps[i];
 189                 if (!keymap)
 190                         continue;
 191                 for (j = 0; j < NR_KEYS; j++) {
 192                         keysym = keymap[j];
 193                         k = ((i & 1) << 7) + j;
 194                         if (KTYP(keysym) == (KT_LATIN | 0xf0) ||
 195                             KTYP(keysym) == (KT_LETTER | 0xf0))
 196                                 ebcasc[k] = KVAL(keysym);
 197                         else if (KTYP(keysym) == (KT_DEAD | 0xf0))
 198                                 ebcasc[k] = ret_diacr[KVAL(keysym)];
 199                 }
 200         }
 201 }
 202 #endif
 203 
 204 /*
 205  * We have a combining character DIACR here, followed by the character CH.
 206  * If the combination occurs in the table, return the corresponding value.
 207  * Otherwise, if CH is a space or equals DIACR, return DIACR.
 208  * Otherwise, conclude that DIACR was not combining after all,
 209  * queue it and return CH.
 210  */
 211 static unsigned int
 212 handle_diacr(struct kbd_data *kbd, unsigned int ch)
 213 {
 214         int i, d;
 215 
 216         d = kbd->diacr;
 217         kbd->diacr = 0;
 218 
 219         for (i = 0; i < kbd->accent_table_size; i++) {
 220                 if (kbd->accent_table[i].diacr == d &&
 221                     kbd->accent_table[i].base == ch)
 222                         return kbd->accent_table[i].result;
 223         }
 224 
 225         if (ch == ' ' || ch == d)
 226                 return d;
 227 
 228         kbd_put_queue(kbd->port, d);
 229         return ch;
 230 }
 231 
 232 /*
 233  * Handle dead key.
 234  */
 235 static void
 236 k_dead(struct kbd_data *kbd, unsigned char value)
 237 {
 238         value = ret_diacr[value];
 239         kbd->diacr = (kbd->diacr ? handle_diacr(kbd, value) : value);
 240 }
 241 
 242 /*
 243  * Normal character handler.
 244  */
 245 static void
 246 k_self(struct kbd_data *kbd, unsigned char value)
 247 {
 248         if (kbd->diacr)
 249                 value = handle_diacr(kbd, value);
 250         kbd_put_queue(kbd->port, value);
 251 }
 252 
 253 /*
 254  * Special key handlers
 255  */
 256 static void
 257 k_ignore(struct kbd_data *kbd, unsigned char value)
 258 {
 259 }
 260 
 261 /*
 262  * Function key handler.
 263  */
 264 static void
 265 k_fn(struct kbd_data *kbd, unsigned char value)
 266 {
 267         if (kbd->func_table[value])
 268                 kbd_puts_queue(kbd->port, kbd->func_table[value]);
 269 }
 270 
 271 static void
 272 k_spec(struct kbd_data *kbd, unsigned char value)
 273 {
 274         if (value >= NR_FN_HANDLER)
 275                 return;
 276         if (kbd->fn_handler[value])
 277                 kbd->fn_handler[value](kbd);
 278 }
 279 
 280 /*
 281  * Put utf8 character to tty flip buffer.
 282  * UTF-8 is defined for words of up to 31 bits,
 283  * but we need only 16 bits here
 284  */
 285 static void
 286 to_utf8(struct tty_port *port, ushort c)
 287 {
 288         if (c < 0x80)
 289                 /*  0******* */
 290                 kbd_put_queue(port, c);
 291         else if (c < 0x800) {
 292                 /* 110***** 10****** */
 293                 kbd_put_queue(port, 0xc0 | (c >> 6));
 294                 kbd_put_queue(port, 0x80 | (c & 0x3f));
 295         } else {
 296                 /* 1110**** 10****** 10****** */
 297                 kbd_put_queue(port, 0xe0 | (c >> 12));
 298                 kbd_put_queue(port, 0x80 | ((c >> 6) & 0x3f));
 299                 kbd_put_queue(port, 0x80 | (c & 0x3f));
 300         }
 301 }
 302 
 303 /*
 304  * Process keycode.
 305  */
 306 void
 307 kbd_keycode(struct kbd_data *kbd, unsigned int keycode)
 308 {
 309         unsigned short keysym;
 310         unsigned char type, value;
 311 
 312         if (!kbd)
 313                 return;
 314 
 315         if (keycode >= 384)
 316                 keysym = kbd->key_maps[5][keycode - 384];
 317         else if (keycode >= 256)
 318                 keysym = kbd->key_maps[4][keycode - 256];
 319         else if (keycode >= 128)
 320                 keysym = kbd->key_maps[1][keycode - 128];
 321         else
 322                 keysym = kbd->key_maps[0][keycode];
 323 
 324         type = KTYP(keysym);
 325         if (type >= 0xf0) {
 326                 type -= 0xf0;
 327                 if (type == KT_LETTER)
 328                         type = KT_LATIN;
 329                 value = KVAL(keysym);
 330 #ifdef CONFIG_MAGIC_SYSRQ              /* Handle the SysRq Hack */
 331                 if (kbd->sysrq) {
 332                         if (kbd->sysrq == K(KT_LATIN, '-')) {
 333                                 kbd->sysrq = 0;
 334                                 handle_sysrq(value);
 335                                 return;
 336                         }
 337                         if (value == '-') {
 338                                 kbd->sysrq = K(KT_LATIN, '-');
 339                                 return;
 340                         }
 341                         /* Incomplete sysrq sequence. */
 342                         (*k_handler[KTYP(kbd->sysrq)])(kbd, KVAL(kbd->sysrq));
 343                         kbd->sysrq = 0;
 344                 } else if ((type == KT_LATIN && value == '^') ||
 345                            (type == KT_DEAD && ret_diacr[value] == '^')) {
 346                         kbd->sysrq = K(type, value);
 347                         return;
 348                 }
 349 #endif
 350                 (*k_handler[type])(kbd, value);
 351         } else
 352                 to_utf8(kbd->port, keysym);
 353 }
 354 
 355 /*
 356  * Ioctl stuff.
 357  */
 358 static int
 359 do_kdsk_ioctl(struct kbd_data *kbd, struct kbentry __user *user_kbe,
 360               int cmd, int perm)
 361 {
 362         struct kbentry tmp;
 363         unsigned long kb_index, kb_table;
 364         ushort *key_map, val, ov;
 365 
 366         if (copy_from_user(&tmp, user_kbe, sizeof(struct kbentry)))
 367                 return -EFAULT;
 368         kb_index = (unsigned long) tmp.kb_index;
 369 #if NR_KEYS < 256
 370         if (kb_index >= NR_KEYS)
 371                 return -EINVAL;
 372 #endif
 373         kb_table = (unsigned long) tmp.kb_table;
 374 #if MAX_NR_KEYMAPS < 256
 375         if (kb_table >= MAX_NR_KEYMAPS)
 376                 return -EINVAL; 
 377         kb_table = array_index_nospec(kb_table , MAX_NR_KEYMAPS);
 378 #endif
 379 
 380         switch (cmd) {
 381         case KDGKBENT:
 382                 key_map = kbd->key_maps[kb_table];
 383                 if (key_map) {
 384                     val = U(key_map[kb_index]);
 385                     if (KTYP(val) >= KBD_NR_TYPES)
 386                         val = K_HOLE;
 387                 } else
 388                     val = (kb_index ? K_HOLE : K_NOSUCHMAP);
 389                 return put_user(val, &user_kbe->kb_value);
 390         case KDSKBENT:
 391                 if (!perm)
 392                         return -EPERM;
 393                 if (!kb_index && tmp.kb_value == K_NOSUCHMAP) {
 394                         /* disallocate map */
 395                         key_map = kbd->key_maps[kb_table];
 396                         if (key_map) {
 397                             kbd->key_maps[kb_table] = NULL;
 398                             kfree(key_map);
 399                         }
 400                         break;
 401                 }
 402 
 403                 if (KTYP(tmp.kb_value) >= KBD_NR_TYPES)
 404                         return -EINVAL;
 405                 if (KVAL(tmp.kb_value) > kbd_max_vals[KTYP(tmp.kb_value)])
 406                         return -EINVAL;
 407 
 408                 if (!(key_map = kbd->key_maps[kb_table])) {
 409                         int j;
 410 
 411                         key_map = kmalloc(sizeof(plain_map),
 412                                                      GFP_KERNEL);
 413                         if (!key_map)
 414                                 return -ENOMEM;
 415                         kbd->key_maps[kb_table] = key_map;
 416                         for (j = 0; j < NR_KEYS; j++)
 417                                 key_map[j] = U(K_HOLE);
 418                 }
 419                 ov = U(key_map[kb_index]);
 420                 if (tmp.kb_value == ov)
 421                         break;  /* nothing to do */
 422                 /*
 423                  * Attention Key.
 424                  */
 425                 if (((ov == K_SAK) || (tmp.kb_value == K_SAK)) &&
 426                     !capable(CAP_SYS_ADMIN))
 427                         return -EPERM;
 428                 key_map[kb_index] = U(tmp.kb_value);
 429                 break;
 430         }
 431         return 0;
 432 }
 433 
 434 static int
 435 do_kdgkb_ioctl(struct kbd_data *kbd, struct kbsentry __user *u_kbs,
 436                int cmd, int perm)
 437 {
 438         unsigned char kb_func;
 439         char *p;
 440         int len;
 441 
 442         /* Get u_kbs->kb_func. */
 443         if (get_user(kb_func, &u_kbs->kb_func))
 444                 return -EFAULT;
 445 #if MAX_NR_FUNC < 256
 446         if (kb_func >= MAX_NR_FUNC)
 447                 return -EINVAL;
 448 #endif
 449 
 450         switch (cmd) {
 451         case KDGKBSENT:
 452                 p = kbd->func_table[kb_func];
 453                 if (p) {
 454                         len = strlen(p);
 455                         if (len >= sizeof(u_kbs->kb_string))
 456                                 len = sizeof(u_kbs->kb_string) - 1;
 457                         if (copy_to_user(u_kbs->kb_string, p, len))
 458                                 return -EFAULT;
 459                 } else
 460                         len = 0;
 461                 if (put_user('\0', u_kbs->kb_string + len))
 462                         return -EFAULT;
 463                 break;
 464         case KDSKBSENT:
 465                 if (!perm)
 466                         return -EPERM;
 467                 p = strndup_user(u_kbs->kb_string, sizeof(u_kbs->kb_string));
 468                 if (IS_ERR(p))
 469                         return PTR_ERR(p);
 470                 kfree(kbd->func_table[kb_func]);
 471                 kbd->func_table[kb_func] = p;
 472                 break;
 473         }
 474         return 0;
 475 }
 476 
 477 int kbd_ioctl(struct kbd_data *kbd, unsigned int cmd, unsigned long arg)
 478 {
 479         struct tty_struct *tty;
 480         void __user *argp;
 481         unsigned int ct;
 482         int perm;
 483 
 484         argp = (void __user *)arg;
 485 
 486         /*
 487          * To have permissions to do most of the vt ioctls, we either have
 488          * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
 489          */
 490         tty = tty_port_tty_get(kbd->port);
 491         /* FIXME this test is pretty racy */
 492         perm = current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG);
 493         tty_kref_put(tty);
 494         switch (cmd) {
 495         case KDGKBTYPE:
 496                 return put_user(KB_101, (char __user *)argp);
 497         case KDGKBENT:
 498         case KDSKBENT:
 499                 return do_kdsk_ioctl(kbd, argp, cmd, perm);
 500         case KDGKBSENT:
 501         case KDSKBSENT:
 502                 return do_kdgkb_ioctl(kbd, argp, cmd, perm);
 503         case KDGKBDIACR:
 504         {
 505                 struct kbdiacrs __user *a = argp;
 506                 struct kbdiacr diacr;
 507                 int i;
 508 
 509                 if (put_user(kbd->accent_table_size, &a->kb_cnt))
 510                         return -EFAULT;
 511                 for (i = 0; i < kbd->accent_table_size; i++) {
 512                         diacr.diacr = kbd->accent_table[i].diacr;
 513                         diacr.base = kbd->accent_table[i].base;
 514                         diacr.result = kbd->accent_table[i].result;
 515                         if (copy_to_user(a->kbdiacr + i, &diacr, sizeof(struct kbdiacr)))
 516                         return -EFAULT;
 517                 }
 518                 return 0;
 519         }
 520         case KDGKBDIACRUC:
 521         {
 522                 struct kbdiacrsuc __user *a = argp;
 523 
 524                 ct = kbd->accent_table_size;
 525                 if (put_user(ct, &a->kb_cnt))
 526                         return -EFAULT;
 527                 if (copy_to_user(a->kbdiacruc, kbd->accent_table,
 528                                  ct * sizeof(struct kbdiacruc)))
 529                         return -EFAULT;
 530                 return 0;
 531         }
 532         case KDSKBDIACR:
 533         {
 534                 struct kbdiacrs __user *a = argp;
 535                 struct kbdiacr diacr;
 536                 int i;
 537 
 538                 if (!perm)
 539                         return -EPERM;
 540                 if (get_user(ct, &a->kb_cnt))
 541                         return -EFAULT;
 542                 if (ct >= MAX_DIACR)
 543                         return -EINVAL;
 544                 kbd->accent_table_size = ct;
 545                 for (i = 0; i < ct; i++) {
 546                         if (copy_from_user(&diacr, a->kbdiacr + i, sizeof(struct kbdiacr)))
 547                                 return -EFAULT;
 548                         kbd->accent_table[i].diacr = diacr.diacr;
 549                         kbd->accent_table[i].base = diacr.base;
 550                         kbd->accent_table[i].result = diacr.result;
 551                 }
 552                 return 0;
 553         }
 554         case KDSKBDIACRUC:
 555         {
 556                 struct kbdiacrsuc __user *a = argp;
 557 
 558                 if (!perm)
 559                         return -EPERM;
 560                 if (get_user(ct, &a->kb_cnt))
 561                         return -EFAULT;
 562                 if (ct >= MAX_DIACR)
 563                         return -EINVAL;
 564                 kbd->accent_table_size = ct;
 565                 if (copy_from_user(kbd->accent_table, a->kbdiacruc,
 566                                    ct * sizeof(struct kbdiacruc)))
 567                         return -EFAULT;
 568                 return 0;
 569         }
 570         default:
 571                 return -ENOIOCTLCMD;
 572         }
 573 }
 574 
 575 EXPORT_SYMBOL(kbd_ioctl);
 576 EXPORT_SYMBOL(kbd_ascebc);
 577 EXPORT_SYMBOL(kbd_free);
 578 EXPORT_SYMBOL(kbd_alloc);
 579 EXPORT_SYMBOL(kbd_keycode);