LXR linux/drivers/s390/char/keyboard.c

   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
  31typedef void (k_handler_fn)(struct kbd_data *, unsigned char);
  32static k_handler_fn K_HANDLERS;
  33static k_handler_fn *k_handler[16] = { K_HANDLERS };
  34
  35/* maximum values each key_handler can handle */
  36static 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};
  40static const int KBD_NR_TYPES = ARRAY_SIZE(kbd_max_vals);
  41
  42static 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 */
  75struct kbd_data *
  76kbd_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
 118out_fn_handler:
 119        kfree(kbd->fn_handler);
 120out_func:
 121        for (i = 0; i < ARRAY_SIZE(ebc_func_table); i++)
 122                kfree(kbd->func_table[i]);
 123        kfree(kbd->func_table);
 124out_maps:
 125        for (i = 0; i < ARRAY_SIZE(ebc_key_maps); i++)
 126                kfree(kbd->key_maps[i]);
 127        kfree(kbd->key_maps);
 128out_kbd:
 129        kfree(kbd);
 130out:
 131        return NULL;
 132}
 133
 134void
 135kbd_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 */
 153void
 154kbd_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 */
 180void
 181kbd_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 */
 211static unsigned int
 212handle_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 */
 235static void
 236k_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 */
 245static void
 246k_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 */
 256static void
 257k_ignore(struct kbd_data *kbd, unsigned char value)
 258{
 259}
 260
 261/*
 262 * Function key handler.
 263 */
 264static void
 265k_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
 271static void
 272k_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 */
 285static void
 286to_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 */
 306void
 307kbd_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 */
 358static int
 359do_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
 434static int
 435do_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
 477int 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
 575EXPORT_SYMBOL(kbd_ioctl);
 576EXPORT_SYMBOL(kbd_ascebc);
 577EXPORT_SYMBOL(kbd_free);
 578EXPORT_SYMBOL(kbd_alloc);
 579EXPORT_SYMBOL(kbd_keycode);
 580