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 <unistd.h>
  19
  20 #include "alloc-util.h"
  21 #include "env-file.h"
  22 #include "fd-util.h"
  23 #include "fileio.h"
  24 #include "io-util.h"
  25 #include "locale-util.h"
  26 #include "log.h"
  27 #include "proc-cmdline.h"
  28 #include "process-util.h"
  29 #include "signal-util.h"
  30 #include "stdio-util.h"
  31 #include "string-util.h"
  32 #include "strv.h"
  33 #include "terminal-util.h"
  34 #include "util.h"
  35 #include "virt.h"
  36
  37 static int verify_vc_device(int fd) {
  38         unsigned char data[] = {
  39                 TIOCL_GETFGCONSOLE,
  40         };
  41
  42         int r;
  43
  44         r = ioctl(fd, TIOCLINUX, data);
  45         if (r < 0)
  46                 return -errno;
  47
  48         return r;
  49 }
  50
  51 static int verify_vc_allocation(unsigned idx) {
  52         char vcname[sizeof("/dev/vcs") + DECIMAL_STR_MAX(unsigned) - 2];
  53
  54         xsprintf(vcname, "/dev/vcs%u", idx);
  55
  56         if (access(vcname, F_OK) < 0)
  57                 return -errno;
  58
  59         return 0;
  60 }
  61
  62 static int verify_vc_allocation_byfd(int fd) {
  63         struct vt_stat vcs = {};
  64
  65         if (ioctl(fd, VT_GETSTATE, &vcs) < 0)
  66                 return -errno;
  67
  68         return verify_vc_allocation(vcs.v_active);
  69 }
  70
  71 static int verify_vc_kbmode(int fd) {
  72         int curr_mode;
  73
  74         /*
  75          * Make sure we only adjust consoles in K_XLATE or K_UNICODE mode.
  76          * Otherwise we would (likely) interfere with X11's processing of the
  77          * key events.
  78          *
  79          * http://lists.freedesktop.org/archives/systemd-devel/2013-February/008573.html
  80          */
  81
  82         if (ioctl(fd, KDGKBMODE, &curr_mode) < 0)
  83                 return -errno;
  84
  85         return IN_SET(curr_mode, K_XLATE, K_UNICODE) ? 0 : -EBUSY;
  86 }
  87
  88 static int toggle_utf8(const char *name, int fd, bool utf8) {
  89         int r;
  90         struct termios tc = {};
  91
  92         assert(name);
  93
  94         r = ioctl(fd, KDSKBMODE, utf8 ? K_UNICODE : K_XLATE);
  95         if (r < 0)
  96                 return log_warning_errno(errno, "Failed to %s UTF-8 kbdmode on %s: %m", enable_disable(utf8), name);
  97
  98         r = loop_write(fd, utf8 ? "\033%G" : "\033%@", 3, false);
  99         if (r < 0)
 100                 return log_warning_errno(r, "Failed to %s UTF-8 term processing on %s: %m", enable_disable(utf8), name);
 101
 102         r = tcgetattr(fd, &tc);
 103         if (r >= 0) {
 104                 SET_FLAG(tc.c_iflag, IUTF8, utf8);
 105                 r = tcsetattr(fd, TCSANOW, &tc);
 106         }
 107         if (r < 0)
 108                 return log_warning_errno(errno, "Failed to %s iutf8 flag on %s: %m", enable_disable(utf8), name);
 109
 110         log_debug("UTF-8 kbdmode %sd on %s", enable_disable(utf8), name);
 111         return 0;
 112 }
 113
 114 static int toggle_utf8_sysfs(bool utf8) {
 115         int r;
 116
 117         r = write_string_file("/sys/module/vt/parameters/default_utf8", one_zero(utf8), WRITE_STRING_FILE_DISABLE_BUFFER);
 118         if (r < 0)
 119                 return log_warning_errno(r, "Failed to %s sysfs UTF-8 flag: %m", enable_disable(utf8));
 120
 121         log_debug("Sysfs UTF-8 flag %sd", enable_disable(utf8));
 122         return 0;
 123 }
 124
 125 static int keyboard_load_and_wait(const char *vc, const char *map, const char *map_toggle, bool utf8) {
 126         const char *args[8];
 127         unsigned i = 0;
 128         pid_t pid;
 129         int r;
 130
 131         /* An empty map means kernel map */
 132         if (isempty(map))
 133                 return 0;
 134
 135         args[i++] = KBD_LOADKEYS;
 136         args[i++] = "-q";
 137         args[i++] = "-C";
 138         args[i++] = vc;
 139         if (utf8)
 140                 args[i++] = "-u";
 141         args[i++] = map;
 142         if (map_toggle)
 143                 args[i++] = map_toggle;
 144         args[i++] = NULL;
 145
 146         if (DEBUG_LOGGING) {
 147                 _cleanup_free_ char *cmd;
 148
 149                 cmd = strv_join((char**) args, " ");
 150                 log_debug("Executing \"%s\"...", strnull(cmd));
 151         }
 152
 153         r = safe_fork("(loadkeys)", FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_RLIMIT_NOFILE_SAFE|FORK_LOG, &pid);
 154         if (r < 0)
 155                 return r;
 156         if (r == 0) {
 157                 execv(args[0], (char **) args);
 158                 _exit(EXIT_FAILURE);
 159         }
 160
 161         return wait_for_terminate_and_check(KBD_LOADKEYS, pid, WAIT_LOG);
 162 }
 163
 164 static int font_load_and_wait(const char *vc, const char *font, const char *map, const char *unimap) {
 165         const char *args[9];
 166         unsigned i = 0;
 167         pid_t pid;
 168         int r;
 169
 170         /* Any part can be set independently */
 171         if (isempty(font) && isempty(map) && isempty(unimap))
 172                 return 0;
 173
 174         args[i++] = KBD_SETFONT;
 175         args[i++] = "-C";
 176         args[i++] = vc;
 177         if (!isempty(map)) {
 178                 args[i++] = "-m";
 179                 args[i++] = map;
 180         }
 181         if (!isempty(unimap)) {
 182                 args[i++] = "-u";
 183                 args[i++] = unimap;
 184         }
 185         if (!isempty(font))
 186                 args[i++] = font;
 187         args[i++] = NULL;
 188
 189         if (DEBUG_LOGGING) {
 190                 _cleanup_free_ char *cmd;
 191
 192                 cmd = strv_join((char**) args, " ");
 193                 log_debug("Executing \"%s\"...", strnull(cmd));
 194         }
 195
 196         r = safe_fork("(setfont)", FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_RLIMIT_NOFILE_SAFE|FORK_LOG, &pid);
 197         if (r < 0)
 198                 return r;
 199         if (r == 0) {
 200                 execv(args[0], (char **) args);
 201                 _exit(EXIT_FAILURE);
 202         }
 203
 204         return wait_for_terminate_and_check(KBD_SETFONT, pid, WAIT_LOG);
 205 }
 206
 207 /*
 208  * A newly allocated VT uses the font from the source VT. Here
 209  * we update all possibly already allocated VTs with the configured
 210  * font. It also allows to restart systemd-vconsole-setup.service,
 211  * to apply a new font to all VTs.
 212  *
 213  * We also setup per-console utf8 related stuff: kbdmode, term
 214  * processing, stty iutf8.
 215  */
 216 static void setup_remaining_vcs(int src_fd, unsigned src_idx, bool utf8) {
 217         struct console_font_op cfo = {
 218                 .op = KD_FONT_OP_GET,
 219                 .width = UINT_MAX, .height = UINT_MAX,
 220                 .charcount = UINT_MAX,
 221         };
 222         struct unimapinit adv = {};
 223         struct unimapdesc unimapd;
 224         _cleanup_free_ struct unipair* unipairs = NULL;
 225         _cleanup_free_ void *fontbuf = NULL;
 226         unsigned i;
 227         int r;
 228
 229         unipairs = new(struct unipair, USHRT_MAX);
 230         if (!unipairs) {
 231                 log_oom();
 232                 return;
 233         }
 234
 235         /* get metadata of the current font (width, height, count) */
 236         r = ioctl(src_fd, KDFONTOP, &cfo);
 237         if (r < 0)
 238                 log_warning_errno(errno, "KD_FONT_OP_GET failed while trying to get the font metadata: %m");
 239         else {
 240                 /* verify parameter sanity first */
 241                 if (cfo.width > 32 || cfo.height > 32 || cfo.charcount > 512)
 242                         log_warning("Invalid font metadata - width: %u (max 32), height: %u (max 32), count: %u (max 512)",
 243                                     cfo.width, cfo.height, cfo.charcount);
 244                 else {
 245                         /*
 246                          * Console fonts supported by the kernel are limited in size to 32 x 32 and maximum 512
 247                          * characters. Thus with 1 bit per pixel it requires up to 65536 bytes. The height always
 248                          * requries 32 per glyph, regardless of the actual height - see the comment above #define
 249                          * max_font_size 65536 in drivers/tty/vt/vt.c for more details.
 250                          */
 251                         fontbuf = malloc_multiply((cfo.width + 7) / 8 * 32, cfo.charcount);
 252                         if (!fontbuf) {
 253                                 log_oom();
 254                                 return;
 255                         }
 256                         /* get fonts from the source console */
 257                         cfo.data = fontbuf;
 258                         r = ioctl(src_fd, KDFONTOP, &cfo);
 259                         if (r < 0)
 260                                 log_warning_errno(errno, "KD_FONT_OP_GET failed while trying to read the font data: %m");
 261                         else {
 262                                 unimapd.entries  = unipairs;
 263                                 unimapd.entry_ct = USHRT_MAX;
 264                                 r = ioctl(src_fd, GIO_UNIMAP, &unimapd);
 265                                 if (r < 0)
 266                                         log_warning_errno(errno, "GIO_UNIMAP failed while trying to read unicode mappings: %m");
 267                                 else
 268                                         cfo.op = KD_FONT_OP_SET;
 269                         }
 270                 }
 271         }
 272
 273         if (cfo.op != KD_FONT_OP_SET)
 274                 log_warning("Fonts will not be copied to remaining consoles");
 275
 276         for (i = 1; i <= 63; i++) {
 277                 char ttyname[sizeof("/dev/tty63")];
 278                 _cleanup_close_ int fd_d = -1;
 279
 280                 if (i == src_idx || verify_vc_allocation(i) < 0)
 281                         continue;
 282
 283                 /* try to open terminal */
 284                 xsprintf(ttyname, "/dev/tty%u", i);
 285                 fd_d = open_terminal(ttyname, O_RDWR|O_CLOEXEC|O_NOCTTY);
 286                 if (fd_d < 0) {
 287                         log_warning_errno(fd_d, "Unable to open tty%u, fonts will not be copied: %m", i);
 288                         continue;
 289                 }
 290
 291                 if (verify_vc_kbmode(fd_d) < 0)
 292                         continue;
 293
 294                 toggle_utf8(ttyname, fd_d, utf8);
 295
 296                 if (cfo.op != KD_FONT_OP_SET)
 297                         continue;
 298
 299                 r = ioctl(fd_d, KDFONTOP, &cfo);
 300                 if (r < 0) {
 301                         int last_errno, mode;
 302
 303                         /* The fonts couldn't have been copied. It might be due to the
 304                          * terminal being in graphical mode. In this case the kernel
 305                          * returns -EINVAL which is too generic for distinguishing this
 306                          * specific case. So we need to retrieve the terminal mode and if
 307                          * the graphical mode is in used, let's assume that something else
 308                          * is using the terminal and the failure was expected as we
 309                          * shouldn't have tried to copy the fonts. */
 310
 311                         last_errno = errno;
 312                         if (ioctl(fd_d, KDGETMODE, &mode) >= 0 && mode != KD_TEXT)
 313                                 log_debug("KD_FONT_OP_SET skipped: tty%u is not in text mode", i);
 314                         else
 315                                 log_warning_errno(last_errno, "KD_FONT_OP_SET failed, fonts will not be copied to tty%u: %m", i);
 316
 317                         continue;
 318                 }
 319
 320                 /*
 321                  * copy unicode translation table unimapd is a ushort count and a pointer
 322                  * to an array of struct unipair { ushort, ushort }
 323                  */
 324                 r = ioctl(fd_d, PIO_UNIMAPCLR, &adv);
 325                 if (r < 0) {
 326                         log_warning_errno(errno, "PIO_UNIMAPCLR failed, unimaps might be incorrect for tty%u: %m", i);
 327                         continue;
 328                 }
 329
 330                 r = ioctl(fd_d, PIO_UNIMAP, &unimapd);
 331                 if (r < 0) {
 332                         log_warning_errno(errno, "PIO_UNIMAP failed, unimaps might be incorrect for tty%u: %m", i);
 333                         continue;
 334                 }
 335
 336                 log_debug("Font and unimap successfully copied to %s", ttyname);
 337         }
 338 }
 339
 340 static int find_source_vc(char **ret_path, unsigned *ret_idx) {
 341         _cleanup_free_ char *path = NULL;
 342         int r, err = 0;
 343         unsigned i;
 344
 345         path = new(char, sizeof("/dev/tty63"));
 346         if (!path)
 347                 return log_oom();
 348
 349         for (i = 1; i <= 63; i++) {
 350                 _cleanup_close_ int fd = -1;
 351
 352                 r = verify_vc_allocation(i);
 353                 if (r < 0) {
 354                         if (!err)
 355                                 err = -r;
 356                         continue;
 357                 }
 358
 359                 sprintf(path, "/dev/tty%u", i);
 360                 fd = open_terminal(path, O_RDWR|O_CLOEXEC|O_NOCTTY);
 361                 if (fd < 0) {
 362                         if (!err)
 363                                 err = -fd;
 364                         continue;
 365                 }
 366                 r = verify_vc_kbmode(fd);
 367                 if (r < 0) {
 368                         if (!err)
 369                                 err = -r;
 370                         continue;
 371                 }
 372
 373                 /* all checks passed, return this one as a source console */
 374                 *ret_idx = i;
 375                 *ret_path = TAKE_PTR(path);
 376                 return TAKE_FD(fd);
 377         }
 378
 379         return log_error_errno(err, "No usable source console found: %m");
 380 }
 381
 382 static int verify_source_vc(char **ret_path, const char *src_vc) {
 383         _cleanup_close_ int fd = -1;
 384         char *path;
 385         int r;
 386
 387         fd = open_terminal(src_vc, O_RDWR|O_CLOEXEC|O_NOCTTY);
 388         if (fd < 0)
 389                 return log_error_errno(fd, "Failed to open %s: %m", src_vc);
 390
 391         r = verify_vc_device(fd);
 392         if (r < 0)
 393                 return log_error_errno(r, "Device %s is not a virtual console: %m", src_vc);
 394
 395         r = verify_vc_allocation_byfd(fd);
 396         if (r < 0)
 397                 return log_error_errno(r, "Virtual console %s is not allocated: %m", src_vc);
 398
 399         r = verify_vc_kbmode(fd);
 400         if (r < 0)
 401                 return log_error_errno(r, "Virtual console %s is not in K_XLATE or K_UNICODE: %m", src_vc);
 402
 403         path = strdup(src_vc);
 404         if (!path)
 405                 return log_oom();
 406
 407         *ret_path = path;
 408         return TAKE_FD(fd);
 409 }
 410
 411 int main(int argc, char **argv) {
 412         _cleanup_free_ char
 413                 *vc = NULL,
 414                 *vc_keymap = NULL, *vc_keymap_toggle = NULL,
 415                 *vc_font = NULL, *vc_font_map = NULL, *vc_font_unimap = NULL;
 416         _cleanup_close_ int fd = -1;
 417         bool utf8, keyboard_ok;
 418         unsigned idx = 0;
 419         int r;
 420
 421         log_setup_service();
 422
 423         umask(0022);
 424
 425         if (argv[1])
 426                 fd = verify_source_vc(&vc, argv[1]);
 427         else
 428                 fd = find_source_vc(&vc, &idx);
 429         if (fd < 0)
 430                 return EXIT_FAILURE;
 431
 432         utf8 = is_locale_utf8();
 433
 434         r = parse_env_file(NULL, "/etc/vconsole.conf",
 435                            "KEYMAP", &vc_keymap,
 436                            "KEYMAP_TOGGLE", &vc_keymap_toggle,
 437                            "FONT", &vc_font,
 438                            "FONT_MAP", &vc_font_map,
 439                            "FONT_UNIMAP", &vc_font_unimap);
 440         if (r < 0 && r != -ENOENT)
 441                 log_warning_errno(r, "Failed to read /etc/vconsole.conf: %m");
 442
 443         /* Let the kernel command line override /etc/vconsole.conf */
 444         r = proc_cmdline_get_key_many(
 445                         PROC_CMDLINE_STRIP_RD_PREFIX,
 446                         "vconsole.keymap", &vc_keymap,
 447                         "vconsole.keymap_toggle", &vc_keymap_toggle,
 448                         "vconsole.font", &vc_font,
 449                         "vconsole.font_map", &vc_font_map,
 450                         "vconsole.font_unimap", &vc_font_unimap,
 451                         /* compatibility with obsolete multiple-dot scheme */
 452                         "vconsole.keymap.toggle", &vc_keymap_toggle,
 453                         "vconsole.font.map", &vc_font_map,
 454                         "vconsole.font.unimap", &vc_font_unimap);
 455         if (r < 0 && r != -ENOENT)
 456                 log_warning_errno(r, "Failed to read /proc/cmdline: %m");
 457
 458         (void) toggle_utf8_sysfs(utf8);
 459         (void) toggle_utf8(vc, fd, utf8);
 460
 461         r = font_load_and_wait(vc, vc_font, vc_font_map, vc_font_unimap);
 462         keyboard_ok = keyboard_load_and_wait(vc, vc_keymap, vc_keymap_toggle, utf8) == 0;
 463
 464         if (idx > 0) {
 465                 if (r == 0)
 466                         setup_remaining_vcs(fd, idx, utf8);
 467                 else if (r == EX_OSERR)
 468                         /* setfont returns EX_OSERR when ioctl(KDFONTOP/PIO_FONTX/PIO_FONTX) fails.
 469                          * This might mean various things, but in particular lack of a graphical
 470                          * console. Let's be generous and not treat this as an error. */
 471                         log_notice("Setting fonts failed with a \"system error\", ignoring.");
 472                 else
 473                         log_warning("Setting source virtual console failed, ignoring remaining ones");
 474         }
 475
 476         return IN_SET(r, 0, EX_OSERR) && keyboard_ok ? EXIT_SUCCESS : EXIT_FAILURE;
 477 }