| /* SPDX-License-Identifier: LGPL-2.1+ */ |
| /*** |
| This file is part of systemd. |
| |
| Copyright 2010 Lennart Poettering |
| |
| systemd is free software; you can redistribute it and/or modify it |
| under the terms of the GNU Lesser General Public License as published by |
| the Free Software Foundation; either version 2.1 of the License, or |
| (at your option) any later version. |
| |
| systemd is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with systemd; If not, see <http://www.gnu.org/licenses/>. |
| ***/ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <string.h> |
| #include <unistd.h> |
| |
| #include "alloc-util.h" |
| #include "fd-util.h" |
| #include "fileio.h" |
| #include "log.h" |
| #include "mkdir.h" |
| #include "path-util.h" |
| #include "process-util.h" |
| #include "string-util.h" |
| #include "terminal-util.h" |
| #include "unit-name.h" |
| #include "util.h" |
| #include "virt.h" |
| |
| static const char *arg_dest = "/tmp"; |
| |
| static int add_symlink(const char *fservice, const char *tservice) { |
| char *from, *to; |
| int r; |
| |
| assert(fservice); |
| assert(tservice); |
| |
| from = strjoina(SYSTEM_DATA_UNIT_PATH "/", fservice); |
| to = strjoina(arg_dest, "/getty.target.wants/", tservice); |
| |
| 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 = -1; |
| 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 > 0 ? -errno : -EIO; |
| |
| return 0; |
| } |
| |
| int main(int argc, char *argv[]) { |
| |
| static const char virtualization_consoles[] = |
| "hvc0\0" |
| "xvc0\0" |
| "hvsi0\0" |
| "sclp_line0\0" |
| "ttysclp0\0" |
| "3270!tty1\0"; |
| |
| _cleanup_free_ char *active = NULL; |
| const char *j; |
| int r; |
| |
| if (argc > 1 && argc != 4) { |
| log_error("This program takes three or no arguments."); |
| return EXIT_FAILURE; |
| } |
| |
| if (argc > 1) |
| arg_dest = argv[1]; |
| |
| log_set_target(LOG_TARGET_SAFE); |
| log_parse_environment(); |
| log_open(); |
| |
| umask(0022); |
| |
| if (detect_container() > 0) { |
| _cleanup_free_ char *container_ttys = NULL; |
| |
| log_debug("Automatically adding console shell."); |
| |
| if (add_symlink("console-getty.service", "console-getty.service") < 0) |
| return EXIT_FAILURE; |
| |
| /* 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. */ |
| |
| r = getenv_for_pid(1, "container_ttys", &container_ttys); |
| if (r > 0) { |
| const char *word, *state; |
| size_t l; |
| |
| FOREACH_WORD(word, l, container_ttys, state) { |
| const char *t; |
| char tty[l + 1]; |
| |
| memcpy(tty, word, l); |
| tty[l] = 0; |
| |
| /* First strip off /dev/ if it is specified */ |
| t = path_startswith(tty, "/dev/"); |
| if (!t) |
| t = tty; |
| |
| /* Then, make sure it's actually a pty */ |
| t = path_startswith(t, "pts/"); |
| if (!t) |
| continue; |
| |
| if (add_container_getty(t) < 0) |
| return EXIT_FAILURE; |
| } |
| } |
| |
| /* Don't add any further magic if we are in a container */ |
| return EXIT_SUCCESS; |
| } |
| |
| if (read_one_line_file("/sys/class/tty/console/active", &active) >= 0) { |
| const char *word, *state; |
| size_t l; |
| |
| /* Automatically add in a serial getty on all active |
| * kernel consoles */ |
| FOREACH_WORD(word, l, active, state) { |
| _cleanup_free_ char *tty = NULL; |
| |
| tty = strndup(word, l); |
| if (!tty) { |
| log_oom(); |
| return EXIT_FAILURE; |
| } |
| |
| /* 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; |
| |
| if (add_serial_getty(tty) < 0) |
| return EXIT_FAILURE; |
| } |
| } |
| |
| /* Automatically add in a serial getty on the first |
| * virtualizer console */ |
| NULSTR_FOREACH(j, virtualization_consoles) { |
| char *p; |
| |
| p = strjoina("/sys/class/tty/", j); |
| if (access(p, F_OK) < 0) |
| continue; |
| |
| if (add_serial_getty(j) < 0) |
| return EXIT_FAILURE; |
| } |
| |
| return EXIT_SUCCESS; |
| } |