+++ /dev/null
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- 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 <sys/socket.h>
-#include <poll.h>
-#include <sys/timerfd.h>
-#include <errno.h>
-#include <unistd.h>
-#include <stddef.h>
-
-#include "systemd/sd-daemon.h"
-#include "systemd/sd-shutdown.h"
-
-#include "log.h"
-#include "macro.h"
-#include "util.h"
-#include "utmp-wtmp.h"
-#include "mkdir.h"
-#include "fileio.h"
-
-union shutdown_buffer {
- struct sd_shutdown_command command;
- char space[offsetof(struct sd_shutdown_command, wall_message) + LINE_MAX];
-};
-
-static int read_packet(int fd, union shutdown_buffer *_b) {
- struct ucred *ucred;
- ssize_t n;
-
- union shutdown_buffer b; /* We maintain our own copy here, in
- * order not to corrupt the last message */
- struct iovec iovec = {
- .iov_base = &b,
- .iov_len = sizeof(b) - 1,
- };
- union {
- struct cmsghdr cmsghdr;
- uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];
- } control = {};
- struct msghdr msghdr = {
- .msg_iov = &iovec,
- .msg_iovlen = 1,
- .msg_control = &control,
- .msg_controllen = sizeof(control),
- };
-
- assert(fd >= 0);
- assert(_b);
-
- n = recvmsg(fd, &msghdr, MSG_DONTWAIT);
- if (n < 0) {
- if (errno == EAGAIN || errno == EINTR)
- return 0;
-
- log_error_errno(errno, "recvmsg(): %m");
- return -errno;
- }
-
- cmsg_close_all(&msghdr);
-
- if (n == 0) {
- log_error("Short read");
- return -EIO;
- }
-
- if (msghdr.msg_controllen < CMSG_LEN(sizeof(struct ucred)) ||
- control.cmsghdr.cmsg_level != SOL_SOCKET ||
- control.cmsghdr.cmsg_type != SCM_CREDENTIALS ||
- control.cmsghdr.cmsg_len != CMSG_LEN(sizeof(struct ucred))) {
- log_warning("Received message without credentials. Ignoring.");
- return 0;
- }
-
- ucred = (struct ucred*) CMSG_DATA(&control.cmsghdr);
- if (ucred->uid != 0) {
- log_warning("Got request from unprivileged user. Ignoring.");
- return 0;
- }
-
- if ((size_t) n < offsetof(struct sd_shutdown_command, wall_message)) {
- log_warning("Message has invalid size. Ignoring.");
- return 0;
- }
-
- if (b.command.mode != SD_SHUTDOWN_NONE &&
- b.command.mode != SD_SHUTDOWN_REBOOT &&
- b.command.mode != SD_SHUTDOWN_POWEROFF &&
- b.command.mode != SD_SHUTDOWN_HALT &&
- b.command.mode != SD_SHUTDOWN_KEXEC) {
- log_warning("Message has invalid mode. Ignoring.");
- return 0;
- }
-
- b.space[n] = 0;
-
- *_b = b;
- return 1;
-}
-
-static void warn_wall(usec_t n, struct sd_shutdown_command *c) {
- char date[FORMAT_TIMESTAMP_MAX];
- const char *prefix;
- _cleanup_free_ char *l = NULL;
-
- assert(c);
- assert(c->warn_wall);
-
- if (n >= c->usec)
- return;
-
- if (c->mode == SD_SHUTDOWN_HALT)
- prefix = "The system is going down for system halt at ";
- else if (c->mode == SD_SHUTDOWN_POWEROFF)
- prefix = "The system is going down for power-off at ";
- else if (c->mode == SD_SHUTDOWN_REBOOT)
- prefix = "The system is going down for reboot at ";
- else if (c->mode == SD_SHUTDOWN_KEXEC)
- prefix = "The system is going down for kexec reboot at ";
- else if (c->mode == SD_SHUTDOWN_NONE)
- prefix = "The system shutdown has been cancelled at ";
- else
- assert_not_reached("Unknown mode!");
-
- if (asprintf(&l, "%s%s%s%s!", c->wall_message, c->wall_message[0] ? "\n" : "",
- prefix, format_timestamp(date, sizeof(date), c->usec)) >= 0)
- utmp_wall(l, NULL, NULL);
- else
- log_error("Failed to allocate wall message");
-}
-
-_const_ static usec_t when_wall(usec_t n, usec_t elapse) {
-
- static const struct {
- usec_t delay;
- usec_t interval;
- } table[] = {
- { 0, USEC_PER_MINUTE },
- { 10 * USEC_PER_MINUTE, 15 * USEC_PER_MINUTE },
- { USEC_PER_HOUR, 30 * USEC_PER_MINUTE },
- { 3 * USEC_PER_HOUR, USEC_PER_HOUR },
- };
-
- usec_t left, sub;
- unsigned i = ELEMENTSOF(table) - 1;
-
- /* If the time is already passed, then don't announce */
- if (n >= elapse)
- return 0;
-
- left = elapse - n;
- while (left < table[i].delay)
- i--;
- sub = (left / table[i].interval) * table[i].interval;
-
- assert(sub < elapse);
- return elapse - sub;
-}
-
-static usec_t when_nologin(usec_t elapse) {
- return elapse > 5*USEC_PER_MINUTE ? elapse - 5*USEC_PER_MINUTE : 1;
-}
-
-static const char *mode_to_string(enum sd_shutdown_mode m) {
- switch (m) {
- case SD_SHUTDOWN_REBOOT:
- return "reboot";
- case SD_SHUTDOWN_POWEROFF:
- return "poweroff";
- case SD_SHUTDOWN_HALT:
- return "halt";
- case SD_SHUTDOWN_KEXEC:
- return "kexec";
- default:
- return NULL;
- }
-}
-
-static int update_schedule_file(struct sd_shutdown_command *c) {
- int r;
- _cleanup_fclose_ FILE *f = NULL;
- _cleanup_free_ char *t = NULL, *temp_path = NULL;
-
- assert(c);
-
- r = mkdir_safe_label("/run/systemd/shutdown", 0755, 0, 0);
- if (r < 0)
- return log_error_errno(r, "Failed to create shutdown subdirectory: %m");
-
- t = cescape(c->wall_message);
- if (!t)
- return log_oom();
-
- r = fopen_temporary("/run/systemd/shutdown/scheduled", &f, &temp_path);
- if (r < 0)
- return log_error_errno(r, "Failed to save information about scheduled shutdowns: %m");
-
- fchmod(fileno(f), 0644);
-
- fprintf(f,
- "USEC="USEC_FMT"\n"
- "WARN_WALL=%i\n"
- "MODE=%s\n",
- c->usec,
- c->warn_wall,
- mode_to_string(c->mode));
-
- if (c->dry_run)
- fputs("DRY_RUN=1\n", f);
-
- if (!isempty(t))
- fprintf(f, "WALL_MESSAGE=%s\n", t);
-
- fflush(f);
-
- if (ferror(f) || rename(temp_path, "/run/systemd/shutdown/scheduled") < 0) {
- log_error_errno(errno, "Failed to write information about scheduled shutdowns: %m");
- r = -errno;
-
- unlink(temp_path);
- unlink("/run/systemd/shutdown/scheduled");
- }
-
- return r;
-}
-
-static bool scheduled(struct sd_shutdown_command *c) {
- return c->usec > 0 && c->mode != SD_SHUTDOWN_NONE;
-}
-
-int main(int argc, char *argv[]) {
- enum {
- FD_SOCKET,
- FD_WALL_TIMER,
- FD_NOLOGIN_TIMER,
- FD_SHUTDOWN_TIMER,
- _FD_MAX
- };
-
- int r = EXIT_FAILURE, n_fds;
- union shutdown_buffer b = {};
- struct pollfd pollfd[_FD_MAX] = {};
- bool exec_shutdown = false, unlink_nologin = false;
- unsigned i;
-
- if (getppid() != 1) {
- log_error("This program should be invoked by init only.");
- return EXIT_FAILURE;
- }
-
- if (argc > 1) {
- log_error("This program does not take arguments.");
- return EXIT_FAILURE;
- }
-
- log_set_target(LOG_TARGET_AUTO);
- log_parse_environment();
- log_open();
-
- umask(0022);
-
- n_fds = sd_listen_fds(true);
- if (n_fds < 0) {
- log_error_errno(r, "Failed to read listening file descriptors from environment: %m");
- return EXIT_FAILURE;
- }
-
- if (n_fds != 1) {
- log_error("Need exactly one file descriptor.");
- return EXIT_FAILURE;
- }
-
- pollfd[FD_SOCKET].fd = SD_LISTEN_FDS_START;
- pollfd[FD_SOCKET].events = POLLIN;
-
- for (i = FD_WALL_TIMER; i < _FD_MAX; i++) {
- pollfd[i].events = POLLIN;
- pollfd[i].fd = timerfd_create(CLOCK_REALTIME, TFD_NONBLOCK|TFD_CLOEXEC);
- if (pollfd[i].fd < 0) {
- log_error_errno(errno, "timerfd_create(): %m");
- goto finish;
- }
- }
-
- log_debug("systemd-shutdownd running as pid "PID_FMT, getpid());
-
- sd_notify(false,
- "READY=1\n"
- "STATUS=Processing requests...");
-
- for (;;) {
- int k;
- usec_t n;
-
- k = poll(pollfd, _FD_MAX, scheduled(&b.command) ? -1 : 0);
- if (k < 0) {
-
- if (errno == EAGAIN || errno == EINTR)
- continue;
-
- log_error_errno(errno, "poll(): %m");
- goto finish;
- }
-
- /* Exit on idle */
- if (k == 0)
- break;
-
- n = now(CLOCK_REALTIME);
-
- if (pollfd[FD_SOCKET].revents) {
-
- k = read_packet(pollfd[FD_SOCKET].fd, &b);
- if (k < 0)
- goto finish;
- else if (k > 0) {
- struct itimerspec its;
- char date[FORMAT_TIMESTAMP_MAX];
-
- if (!scheduled(&b.command)) {
- log_info("Shutdown canceled.");
- if (b.command.warn_wall)
- warn_wall(0, &b.command);
- break;
- }
-
- zero(its);
- if (b.command.warn_wall) {
- /* Send wall messages every so often */
- timespec_store(&its.it_value, when_wall(n, b.command.usec));
-
- /* Warn immediately if less than 15 minutes are left */
- if (n < b.command.usec &&
- n + 15*USEC_PER_MINUTE >= b.command.usec)
- warn_wall(n, &b.command);
- }
- if (timerfd_settime(pollfd[FD_WALL_TIMER].fd, TFD_TIMER_ABSTIME, &its, NULL) < 0) {
- log_error_errno(errno, "timerfd_settime(): %m");
- goto finish;
- }
-
- /* Disallow logins 5 minutes prior to shutdown */
- zero(its);
- timespec_store(&its.it_value, when_nologin(b.command.usec));
- if (timerfd_settime(pollfd[FD_NOLOGIN_TIMER].fd, TFD_TIMER_ABSTIME, &its, NULL) < 0) {
- log_error_errno(errno, "timerfd_settime(): %m");
- goto finish;
- }
-
- /* Shutdown after the specified time is reached */
- zero(its);
- timespec_store(&its.it_value, b.command.usec);
- if (timerfd_settime(pollfd[FD_SHUTDOWN_TIMER].fd, TFD_TIMER_ABSTIME, &its, NULL) < 0) {
- log_error_errno(errno, "timerfd_settime(): %m");
- goto finish;
- }
-
- update_schedule_file(&b.command);
-
- sd_notifyf(false,
- "STATUS=Shutting down at %s (%s)...",
- format_timestamp(date, sizeof(date), b.command.usec),
- mode_to_string(b.command.mode));
-
- log_info("Shutting down at %s (%s)...", date, mode_to_string(b.command.mode));
- }
- }
-
- if (pollfd[FD_WALL_TIMER].revents) {
- struct itimerspec its = {};
-
- warn_wall(n, &b.command);
- flush_fd(pollfd[FD_WALL_TIMER].fd);
-
- /* Restart timer */
- timespec_store(&its.it_value, when_wall(n, b.command.usec));
- if (timerfd_settime(pollfd[FD_WALL_TIMER].fd, TFD_TIMER_ABSTIME, &its, NULL) < 0) {
- log_error_errno(errno, "timerfd_settime(): %m");
- goto finish;
- }
- }
-
- if (pollfd[FD_NOLOGIN_TIMER].revents) {
- int e;
-
- log_info("Creating /run/nologin, blocking further logins...");
-
- e = write_string_file_atomic("/run/nologin", "System is going down.");
- if (e < 0)
- log_error_errno(e, "Failed to create /run/nologin: %m");
- else
- unlink_nologin = true;
-
- flush_fd(pollfd[FD_NOLOGIN_TIMER].fd);
- }
-
- if (pollfd[FD_SHUTDOWN_TIMER].revents) {
- exec_shutdown = true;
- goto finish;
- }
- }
-
- r = EXIT_SUCCESS;
-
- log_debug("systemd-shutdownd stopped as pid "PID_FMT, getpid());
-
-finish:
-
- for (i = 0; i < _FD_MAX; i++)
- safe_close(pollfd[i].fd);
-
- if (unlink_nologin)
- unlink("/run/nologin");
-
- unlink("/run/systemd/shutdown/scheduled");
-
- if (exec_shutdown && !b.command.dry_run) {
- char sw[3];
-
- sw[0] = '-';
- sw[1] = b.command.mode;
- sw[2] = 0;
-
- execl(SYSTEMCTL_BINARY_PATH,
- "shutdown",
- sw,
- "now",
- (b.command.warn_wall && b.command.wall_message[0]) ? b.command.wall_message :
- (b.command.warn_wall ? NULL : "--no-wall"),
- NULL);
-
- log_error_errno(errno, "Failed to execute /sbin/shutdown: %m");
- }
-
- sd_notify(false,
- "STOPPING=\n"
- "STATUS=Exiting...");
-
- return r;
-}
~ianmdlvl / elogind.git / commitdiff