| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <unistd.h> |
| |
| #include "alloc-util.h" |
| #include "errno-util.h" |
| #include "fd-util.h" |
| #include "fileio.h" |
| #include "generator.h" |
| #include "log.h" |
| #include "mkdir-label.h" |
| #include "parse-util.h" |
| #include "path-util.h" |
| #include "process-util.h" |
| #include "proc-cmdline.h" |
| #include "strv.h" |
| #include "terminal-util.h" |
| #include "unit-name.h" |
| #include "virt.h" |
| |
| static const char *arg_dest = NULL; |
| static bool arg_enabled = true; |
| |
| static int add_symlink(const char *fservice, const char *tservice) { |
| char *from, *to; |
| int r; |
| |
| assert(fservice); |
| assert(tservice); |
| |
| from = strjoina(SYSTEM_DATA_UNIT_DIR "/", fservice); |
| to = strjoina(arg_dest, "/getty.target.wants/", tservice); |
| |
| (void) mkdir_parents_label(to, 0755); |
| |
| r = symlink(from, to); |
| if (r < 0) { |
| /* In case console=hvc0 is passed this will very likely result in EEXIST */ |
| if (errno == EEXIST) |
| return 0; |
| |
| return log_error_errno(errno, "Failed to create symlink %s: %m", to); |
| } |
| |
| return 0; |
| } |
| |
| static int add_serial_getty(const char *tty) { |
| _cleanup_free_ char *n = NULL; |
| int r; |
| |
| assert(tty); |
| |
| log_debug("Automatically adding serial getty for /dev/%s.", tty); |
| |
| r = unit_name_from_path_instance("serial-getty", tty, ".service", &n); |
| if (r < 0) |
| return log_error_errno(r, "Failed to generate service name: %m"); |
| |
| return add_symlink("serial-getty@.service", n); |
| } |
| |
| static int add_container_getty(const char *tty) { |
| _cleanup_free_ char *n = NULL; |
| int r; |
| |
| assert(tty); |
| |
| log_debug("Automatically adding container getty for /dev/pts/%s.", tty); |
| |
| r = unit_name_from_path_instance("container-getty", tty, ".service", &n); |
| if (r < 0) |
| return log_error_errno(r, "Failed to generate service name: %m"); |
| |
| return add_symlink("container-getty@.service", n); |
| } |
| |
| static int verify_tty(const char *name) { |
| _cleanup_close_ int fd = -EBADF; |
| const char *p; |
| |
| /* Some TTYs are weird and have been enumerated but don't work |
| * when you try to use them, such as classic ttyS0 and |
| * friends. Let's check that and open the device and run |
| * isatty() on it. */ |
| |
| p = strjoina("/dev/", name); |
| |
| /* O_NONBLOCK is essential here, to make sure we don't wait |
| * for DCD */ |
| fd = open(p, O_RDWR|O_NONBLOCK|O_NOCTTY|O_CLOEXEC|O_NOFOLLOW); |
| if (fd < 0) |
| return -errno; |
| |
| errno = 0; |
| if (isatty(fd) <= 0) |
| return errno_or_else(EIO); |
| |
| return 0; |
| } |
| |
| static int run_container(void) { |
| _cleanup_free_ char *container_ttys = NULL; |
| int r; |
| |
| log_debug("Automatically adding console shell."); |
| |
| r = add_symlink("console-getty.service", "console-getty.service"); |
| if (r < 0) |
| return r; |
| |
| /* When $container_ttys is set for PID 1, spawn gettys on all ptys named therein. |
| * Note that despite the variable name we only support ptys here. */ |
| |
| (void) getenv_for_pid(1, "container_ttys", &container_ttys); |
| |
| for (const char *p = container_ttys;;) { |
| _cleanup_free_ char *word = NULL; |
| |
| r = extract_first_word(&p, &word, NULL, 0); |
| if (r < 0) |
| return log_error_errno(r, "Failed to parse $container_ttys: %m"); |
| if (r == 0) |
| return 0; |
| |
| const char *tty = word; |
| |
| /* First strip off /dev/ if it is specified */ |
| tty = path_startswith(tty, "/dev/") ?: tty; |
| |
| /* Then, make sure it's actually a pty */ |
| tty = path_startswith(tty, "pts/"); |
| if (!tty) |
| continue; |
| |
| r = add_container_getty(tty); |
| if (r < 0) |
| return r; |
| } |
| } |
| |
| static int parse_proc_cmdline_item(const char *key, const char *value, void *data) { |
| int r; |
| |
| assert(key); |
| |
| if (proc_cmdline_key_streq(key, "systemd.getty_auto")) { |
| r = value ? parse_boolean(value) : 1; |
| if (r < 0) |
| log_warning_errno(r, "Failed to parse getty_auto switch \"%s\", ignoring: %m", value); |
| else |
| arg_enabled = r; |
| } |
| |
| return 0; |
| } |
| |
| static int run(const char *dest, const char *dest_early, const char *dest_late) { |
| _cleanup_free_ char *getty_auto = NULL; |
| int r; |
| |
| assert_se(arg_dest = dest); |
| |
| r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0); |
| if (r < 0) |
| log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m"); |
| |
| r = getenv_for_pid(1, "SYSTEMD_GETTY_AUTO", &getty_auto); |
| if (r < 0) |
| log_warning_errno(r, "Failed to parse $SYSTEMD_GETTY_AUTO environment variable, ignoring: %m"); |
| else if (r > 0) { |
| r = parse_boolean(getty_auto); |
| if (r < 0) |
| log_warning_errno(r, "Failed to parse $SYSTEMD_GETTY_AUTO value \"%s\", ignoring: %m", getty_auto); |
| else |
| arg_enabled = r; |
| } |
| |
| if (!arg_enabled) { |
| log_debug("Disabled, exiting."); |
| return 0; |
| } |
| |
| if (detect_container() > 0) |
| /* Add console shell and look at $container_ttys, but don't do add any |
| * further magic if we are in a container. */ |
| return run_container(); |
| |
| /* Automatically add in a serial getty on all active kernel consoles */ |
| _cleanup_free_ char *active = NULL; |
| (void) read_one_line_file("/sys/class/tty/console/active", &active); |
| for (const char *p = active;;) { |
| _cleanup_free_ char *tty = NULL; |
| |
| r = extract_first_word(&p, &tty, NULL, 0); |
| if (r < 0) |
| return log_error_errno(r, "Failed to parse /sys/class/tty/console/active: %m"); |
| if (r == 0) |
| break; |
| |
| /* We assume that gettys on virtual terminals are started via manual configuration and do |
| * this magic only for non-VC terminals. */ |
| |
| if (isempty(tty) || tty_is_vc(tty)) |
| continue; |
| |
| if (verify_tty(tty) < 0) |
| continue; |
| |
| r = add_serial_getty(tty); |
| if (r < 0) |
| return r; |
| } |
| |
| /* Automatically add in a serial getty on the first virtualizer console */ |
| FOREACH_STRING(j, |
| "hvc0", |
| "xvc0", |
| "hvsi0", |
| "sclp_line0", |
| "ttysclp0", |
| "3270!tty1") { |
| _cleanup_free_ char *p = NULL; |
| |
| p = path_join("/sys/class/tty", j); |
| if (!p) |
| return -ENOMEM; |
| if (access(p, F_OK) < 0) |
| continue; |
| |
| r = add_serial_getty(j); |
| if (r < 0) |
| return r; |
| } |
| |
| return 0; |
| } |
| |
| DEFINE_MAIN_GENERATOR_FUNCTION(run); |