src/vconsole/vconsole-setup.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   Copyright © 2016 Michal Soltys <soltys@ziu.info>
   4 ***/
   5
   6 #include <errno.h>
   7 #include <fcntl.h>
   8 #include <limits.h>
   9 #include <linux/kd.h>
  10 #include <linux/tiocl.h>
  11 #include <linux/vt.h>
  12 #include <stdbool.h>
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <sys/ioctl.h>
  16 #include <sysexits.h>
  17 #include <termios.h>
  18 #include <sys/stat.h>
  19 #include <sys/types.h>
  20 #include <unistd.h>
  21
  22 #include "alloc-util.h"
  23 #include "env-file.h"
  24 #include "fd-util.h"
  25 #include "fileio.h"
  26 #include "io-util.h"
  27 #include "locale-util.h"
  28 #include "log.h"
  29 #include "proc-cmdline.h"
  30 #include "process-util.h"
  31 #include "signal-util.h"
  32 #include "stdio-util.h"
  33 #include "string-util.h"
  34 #include "strv.h"
  35 #include "terminal-util.h"
  36 #include "util.h"
  37 #include "virt.h"
  38
  39 static int verify_vc_device(int fd) {
  40         unsigned char data[] = {
  41                 TIOCL_GETFGCONSOLE,
  42         };
  43
  44         int r;
  45
  46         r = ioctl(fd, TIOCLINUX, data);
  47         if (r < 0)
  48                 return -errno;
  49
  50         return r;
  51 }
  52
  53 static int verify_vc_allocation(unsigned idx) {
  54         char vcname[sizeof("/dev/vcs") + DECIMAL_STR_MAX(unsigned) - 2];
  55
  56         xsprintf(vcname, "/dev/vcs%u", idx);
  57
  58         if (access(vcname, F_OK) < 0)
  59                 return -errno;
  60
  61         return 0;
  62 }
  63
  64 static int verify_vc_allocation_byfd(int fd) {
  65         struct vt_stat vcs = {};
  66
  67         if (ioctl(fd, VT_GETSTATE, &vcs) < 0)
  68                 return -errno;
  69
  70         return verify_vc_allocation(vcs.v_active);
  71 }
  72
  73 static int verify_vc_kbmode(int fd) {
  74         int curr_mode;
  75
  76         /*
  77          * Make sure we only adjust consoles in K_XLATE or K_UNICODE mode.
  78          * Otherwise we would (likely) interfere with X11's processing of the
  79          * key events.
  80          *
  81          * http://lists.freedesktop.org/archives/systemd-devel/2013-February/008573.html
  82          */
  83
  84         if (ioctl(fd, KDGKBMODE, &curr_mode) < 0)
  85                 return -errno;
  86
  87         return IN_SET(curr_mode, K_XLATE, K_UNICODE) ? 0 : -EBUSY;
  88 }
  89
  90 static int toggle_utf8_vc(const char *name, int fd, bool utf8) {
  91         int r;
  92         struct termios tc = {};
  93
  94         assert(name);
  95         assert(fd >= 0);
  96
  97         r = ioctl(fd, KDSKBMODE, utf8 ? K_UNICODE : K_XLATE);
  98         if (r < 0)
  99                 return log_warning_errno(errno, "Failed to %s UTF-8 kbdmode on %s: %m", enable_disable(utf8), name);
 100
 101         r = loop_write(fd, utf8 ? "\033%G" : "\033%@", 3, false);
 102         if (r < 0)
 103                 return log_warning_errno(r, "Failed to %s UTF-8 term processing on %s: %m", enable_disable(utf8), name);
 104
 105         r = tcgetattr(fd, &tc);
 106         if (r >= 0) {
 107                 SET_FLAG(tc.c_iflag, IUTF8, utf8);
 108                 r = tcsetattr(fd, TCSANOW, &tc);
 109         }
 110         if (r < 0)
 111                 return log_warning_errno(errno, "Failed to %s iutf8 flag on %s: %m", enable_disable(utf8), name);
 112
 113         log_debug("UTF-8 kbdmode %sd on %s", enable_disable(utf8), name);
 114         return 0;
 115 }
 116
 117 static int toggle_utf8_sysfs(bool utf8) {
 118         int r;
 119
 120         r = write_string_file("/sys/module/vt/parameters/default_utf8", one_zero(utf8), WRITE_STRING_FILE_DISABLE_BUFFER);
 121         if (r < 0)
 122                 return log_warning_errno(r, "Failed to %s sysfs UTF-8 flag: %m", enable_disable(utf8));
 123
 124         log_debug("Sysfs UTF-8 flag %sd", enable_disable(utf8));
 125         return 0;
 126 }
 127
 128 static int keyboard_load_and_wait(const char *vc, const char *map, const char *map_toggle, bool utf8) {
 129         const char *args[8];
 130         unsigned i = 0;
 131         pid_t pid;
 132         int r;
 133
 134         /* An empty map means kernel map */
 135         if (isempty(map))
 136                 return 0;
 137
 138         args[i++] = KBD_LOADKEYS;
 139         args[i++] = "-q";
 140         args[i++] = "-C";
 141         args[i++] = vc;
 142         if (utf8)
 143                 args[i++] = "-u";
 144         args[i++] = map;
 145         if (map_toggle)
 146                 args[i++] = map_toggle;
 147         args[i++] = NULL;
 148
 149         if (DEBUG_LOGGING) {
 150                 _cleanup_free_ char *cmd;
 151
 152                 cmd = strv_join((char**) args, " ");
 153                 log_debug("Executing \"%s\"...", strnull(cmd));
 154         }
 155
 156         r = safe_fork("(loadkeys)", FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_RLIMIT_NOFILE_SAFE|FORK_LOG, &pid);
 157         if (r < 0)
 158                 return r;
 159         if (r == 0) {
 160                 execv(args[0], (char **) args);
 161                 _exit(EXIT_FAILURE);
 162         }
 163
 164         return wait_for_terminate_and_check(KBD_LOADKEYS, pid, WAIT_LOG);
 165 }
 166
 167 static int font_load_and_wait(const char *vc, const char *font, const char *map, const char *unimap) {
 168         const char *args[9];
 169         unsigned i = 0;
 170         pid_t pid;
 171         int r;
 172
 173         /* Any part can be set independently */
 174         if (isempty(font) && isempty(map) && isempty(unimap))
 175                 return 0;
 176
 177         args[i++] = KBD_SETFONT;
 178         args[i++] = "-C";
 179         args[i++] = vc;
 180         if (!isempty(map)) {
 181                 args[i++] = "-m";
 182                 args[i++] = map;
 183         }
 184         if (!isempty(unimap)) {
 185                 args[i++] = "-u";
 186                 args[i++] = unimap;
 187         }
 188         if (!isempty(font))
 189                 args[i++] = font;
 190         args[i++] = NULL;
 191
 192         if (DEBUG_LOGGING) {
 193                 _cleanup_free_ char *cmd;
 194
 195                 cmd = strv_join((char**) args, " ");
 196                 log_debug("Executing \"%s\"...", strnull(cmd));
 197         }
 198
 199         r = safe_fork("(setfont)", FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_RLIMIT_NOFILE_SAFE|FORK_LOG, &pid);
 200         if (r < 0)
 201                 return r;
 202         if (r == 0) {
 203                 execv(args[0], (char **) args);
 204                 _exit(EXIT_FAILURE);
 205         }
 206
 207         return wait_for_terminate_and_check(KBD_SETFONT, pid, WAIT_LOG);
 208 }
 209
 210 /*
 211  * A newly allocated VT uses the font from the source VT. Here
 212  * we update all possibly already allocated VTs with the configured
 213  * font. It also allows to restart systemd-vconsole-setup.service,
 214  * to apply a new font to all VTs.
 215  *
 216  * We also setup per-console utf8 related stuff: kbdmode, term
 217  * processing, stty iutf8.
 218  */
 219 static void setup_remaining_vcs(int src_fd, unsigned src_idx, bool utf8) {
 220         struct console_font_op cfo = {
 221                 .op = KD_FONT_OP_GET,
 222                 .width = UINT_MAX, .height = UINT_MAX,
 223                 .charcount = UINT_MAX,
 224         };
 225         struct unimapinit adv = {};
 226         struct unimapdesc unimapd;
 227         _cleanup_free_ struct unipair* unipairs = NULL;
 228         _cleanup_free_ void *fontbuf = NULL;
 229         unsigned i;
 230         int r;
 231
 232         unipairs = new(struct unipair, USHRT_MAX);
 233         if (!unipairs) {
 234                 log_oom();
 235                 return;
 236         }
 237
 238         /* get metadata of the current font (width, height, count) */
 239         r = ioctl(src_fd, KDFONTOP, &cfo);
 240         if (r < 0)
 241                 log_warning_errno(errno, "KD_FONT_OP_GET failed while trying to get the font metadata: %m");
 242         else {
 243                 /* verify parameter sanity first */
 244                 if (cfo.width > 32 || cfo.height > 32 || cfo.charcount > 512)
 245                         log_warning("Invalid font metadata - width: %u (max 32), height: %u (max 32), count: %u (max 512)",
 246                                     cfo.width, cfo.height, cfo.charcount);
 247                 else {
 248                         /*
 249                          * Console fonts supported by the kernel are limited in size to 32 x 32 and maximum 512
 250                          * characters. Thus with 1 bit per pixel it requires up to 65536 bytes. The height always
 251                          * requires 32 per glyph, regardless of the actual height - see the comment above #define
 252                          * max_font_size 65536 in drivers/tty/vt/vt.c for more details.
 253                          */
 254                         fontbuf = malloc_multiply((cfo.width + 7) / 8 * 32, cfo.charcount);
 255                         if (!fontbuf) {
 256                                 log_oom();
 257                                 return;
 258                         }
 259                         /* get fonts from the source console */
 260                         cfo.data = fontbuf;
 261                         r = ioctl(src_fd, KDFONTOP, &cfo);
 262                         if (r < 0)
 263                                 log_warning_errno(errno, "KD_FONT_OP_GET failed while trying to read the font data: %m");
 264                         else {
 265                                 unimapd.entries  = unipairs;
 266                                 unimapd.entry_ct = USHRT_MAX;
 267                                 r = ioctl(src_fd, GIO_UNIMAP, &unimapd);
 268                                 if (r < 0)
 269                                         log_warning_errno(errno, "GIO_UNIMAP failed while trying to read unicode mappings: %m");
 270                                 else
 271                                         cfo.op = KD_FONT_OP_SET;
 272                         }
 273                 }
 274         }
 275
 276         if (cfo.op != KD_FONT_OP_SET)
 277                 log_warning("Fonts will not be copied to remaining consoles");
 278
 279         for (i = 1; i <= 63; i++) {
 280                 char ttyname[sizeof("/dev/tty63")];
 281                 _cleanup_close_ int fd_d = -1;
 282
 283                 if (i == src_idx || verify_vc_allocation(i) < 0)
 284                         continue;
 285
 286                 /* try to open terminal */
 287                 xsprintf(ttyname, "/dev/tty%u", i);
 288                 fd_d = open_terminal(ttyname, O_RDWR|O_CLOEXEC|O_NOCTTY);
 289                 if (fd_d < 0) {
 290                         log_warning_errno(fd_d, "Unable to open tty%u, fonts will not be copied: %m", i);
 291                         continue;
 292                 }
 293
 294                 if (verify_vc_kbmode(fd_d) < 0)
 295                         continue;
 296
 297                 (void) toggle_utf8_vc(ttyname, fd_d, utf8);
 298
 299                 if (cfo.op != KD_FONT_OP_SET)
 300                         continue;
 301
 302                 r = ioctl(fd_d, KDFONTOP, &cfo);
 303                 if (r < 0) {
 304                         int last_errno, mode;
 305
 306                         /* The fonts couldn't have been copied. It might be due to the
 307                          * terminal being in graphical mode. In this case the kernel
 308                          * returns -EINVAL which is too generic for distinguishing this
 309                          * specific case. So we need to retrieve the terminal mode and if
 310                          * the graphical mode is in used, let's assume that something else
 311                          * is using the terminal and the failure was expected as we
 312                          * shouldn't have tried to copy the fonts. */
 313
 314                         last_errno = errno;
 315                         if (ioctl(fd_d, KDGETMODE, &mode) >= 0 && mode != KD_TEXT)
 316                                 log_debug("KD_FONT_OP_SET skipped: tty%u is not in text mode", i);
 317                         else
 318                                 log_warning_errno(last_errno, "KD_FONT_OP_SET failed, fonts will not be copied to tty%u: %m", i);
 319
 320                         continue;
 321                 }
 322
 323                 /*
 324                  * copy unicode translation table unimapd is a ushort count and a pointer
 325                  * to an array of struct unipair { ushort, ushort }
 326                  */
 327                 r = ioctl(fd_d, PIO_UNIMAPCLR, &adv);
 328                 if (r < 0) {
 329                         log_warning_errno(errno, "PIO_UNIMAPCLR failed, unimaps might be incorrect for tty%u: %m", i);
 330                         continue;
 331                 }
 332
 333                 r = ioctl(fd_d, PIO_UNIMAP, &unimapd);
 334                 if (r < 0) {
 335                         log_warning_errno(errno, "PIO_UNIMAP failed, unimaps might be incorrect for tty%u: %m", i);
 336                         continue;
 337                 }
 338
 339                 log_debug("Font and unimap successfully copied to %s", ttyname);
 340         }
 341 }
 342
 343 static int find_source_vc(char **ret_path, unsigned *ret_idx) {
 344         _cleanup_free_ char *path = NULL;
 345         int r, err = 0;
 346         unsigned i;
 347
 348         path = new(char, sizeof("/dev/tty63"));
 349         if (!path)
 350                 return log_oom();
 351
 352         for (i = 1; i <= 63; i++) {
 353                 _cleanup_close_ int fd = -1;
 354
 355                 r = verify_vc_allocation(i);
 356                 if (r < 0) {
 357                         if (!err)
 358                                 err = -r;
 359                         continue;
 360                 }
 361
 362                 sprintf(path, "/dev/tty%u", i);
 363                 fd = open_terminal(path, O_RDWR|O_CLOEXEC|O_NOCTTY);
 364                 if (fd < 0) {
 365                         if (!err)
 366                                 err = -fd;
 367                         continue;
 368                 }
 369                 r = verify_vc_kbmode(fd);
 370                 if (r < 0) {
 371                         if (!err)
 372                                 err = -r;
 373                         continue;
 374                 }
 375
 376                 /* all checks passed, return this one as a source console */
 377                 *ret_idx = i;
 378                 *ret_path = TAKE_PTR(path);
 379                 return TAKE_FD(fd);
 380         }
 381
 382         return log_error_errno(err, "No usable source console found: %m");
 383 }
 384
 385 static int verify_source_vc(char **ret_path, const char *src_vc) {
 386         _cleanup_close_ int fd = -1;
 387         char *path;
 388         int r;
 389
 390         fd = open_terminal(src_vc, O_RDWR|O_CLOEXEC|O_NOCTTY);
 391         if (fd < 0)
 392                 return log_error_errno(fd, "Failed to open %s: %m", src_vc);
 393
 394         r = verify_vc_device(fd);
 395         if (r < 0)
 396                 return log_error_errno(r, "Device %s is not a virtual console: %m", src_vc);
 397
 398         r = verify_vc_allocation_byfd(fd);
 399         if (r < 0)
 400                 return log_error_errno(r, "Virtual console %s is not allocated: %m", src_vc);
 401
 402         r = verify_vc_kbmode(fd);
 403         if (r < 0)
 404                 return log_error_errno(r, "Virtual console %s is not in K_XLATE or K_UNICODE: %m", src_vc);
 405
 406         path = strdup(src_vc);
 407         if (!path)
 408                 return log_oom();
 409
 410         *ret_path = path;
 411         return TAKE_FD(fd);
 412 }
 413
 414 int main(int argc, char **argv) {
 415         _cleanup_free_ char
 416                 *vc = NULL,
 417                 *vc_keymap = NULL, *vc_keymap_toggle = NULL,
 418                 *vc_font = NULL, *vc_font_map = NULL, *vc_font_unimap = NULL;
 419         _cleanup_close_ int fd = -1;
 420         bool utf8, keyboard_ok;
 421         unsigned idx = 0;
 422         int r;
 423
 424         log_setup_service();
 425
 426         umask(0022);
 427
 428         if (argv[1])
 429                 fd = verify_source_vc(&vc, argv[1]);
 430         else
 431                 fd = find_source_vc(&vc, &idx);
 432         if (fd < 0)
 433                 return EXIT_FAILURE;
 434
 435         utf8 = is_locale_utf8();
 436
 437         r = parse_env_file(NULL, "/etc/vconsole.conf",
 438                            "KEYMAP", &vc_keymap,
 439                            "KEYMAP_TOGGLE", &vc_keymap_toggle,
 440                            "FONT", &vc_font,
 441                            "FONT_MAP", &vc_font_map,
 442                            "FONT_UNIMAP", &vc_font_unimap);
 443         if (r < 0 && r != -ENOENT)
 444                 log_warning_errno(r, "Failed to read /etc/vconsole.conf: %m");
 445
 446         /* Let the kernel command line override /etc/vconsole.conf */
 447         r = proc_cmdline_get_key_many(
 448                         PROC_CMDLINE_STRIP_RD_PREFIX,
 449                         "vconsole.keymap", &vc_keymap,
 450                         "vconsole.keymap_toggle", &vc_keymap_toggle,
 451                         "vconsole.font", &vc_font,
 452                         "vconsole.font_map", &vc_font_map,
 453                         "vconsole.font_unimap", &vc_font_unimap,
 454                         /* compatibility with obsolete multiple-dot scheme */
 455                         "vconsole.keymap.toggle", &vc_keymap_toggle,
 456                         "vconsole.font.map", &vc_font_map,
 457                         "vconsole.font.unimap", &vc_font_unimap);
 458         if (r < 0 && r != -ENOENT)
 459                 log_warning_errno(r, "Failed to read /proc/cmdline: %m");
 460
 461         (void) toggle_utf8_sysfs(utf8);
 462         (void) toggle_utf8_vc(vc, fd, utf8);
 463
 464         r = font_load_and_wait(vc, vc_font, vc_font_map, vc_font_unimap);
 465         keyboard_ok = keyboard_load_and_wait(vc, vc_keymap, vc_keymap_toggle, utf8) == 0;
 466
 467         if (idx > 0) {
 468                 if (r == 0)
 469                         setup_remaining_vcs(fd, idx, utf8);
 470                 else if (r == EX_OSERR)
 471                         /* setfont returns EX_OSERR when ioctl(KDFONTOP/PIO_FONTX/PIO_FONTX) fails.
 472                          * This might mean various things, but in particular lack of a graphical
 473                          * console. Let's be generous and not treat this as an error. */
 474                         log_notice("Setting fonts failed with a \"system error\", ignoring.");
 475                 else
 476                         log_warning("Setting source virtual console failed, ignoring remaining ones");
 477         }
 478
 479         return IN_SET(r, 0, EX_OSERR) && keyboard_ok ? EXIT_SUCCESS : EXIT_FAILURE;
 480 }