From 4a91795b56e8e4358f7463f40b45ee4ee593d99c Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Wed, 22 Apr 2015 17:20:42 +0200 Subject: [PATCH] logind: add code for UTMP wall messages Add a timer to print UTMP wall messages so that it repeatedly informs users about a scheduled shutdown: * every 1 minute with less than 10 minutes to go * every 15 minutes with less than 60 minutes to go * every 30 minutes with less than 180 minutes (3 hours) to go * every 60 minutes if more than that to go This functionality only active if the .EnableWallMessages DBus property is set to true. Also, a custom string can be added to the wall message, set through the WallMessagePrefix property. --- src/login/logind-dbus.c | 40 +++++++++ src/login/logind-utmp.c | 182 ++++++++++++++++++++++++++++++++++++++++ src/login/logind.c | 3 + src/login/logind.h | 9 ++ 4 files changed, 234 insertions(+) create mode 100644 src/login/logind-utmp.c diff --git a/src/login/logind-dbus.c b/src/login/logind-dbus.c index 0fcf2cc96..80514f3d2 100644 --- a/src/login/logind-dbus.c +++ b/src/login/logind-dbus.c @@ -43,6 +43,7 @@ #include "formats-util.h" #include "process-util.h" #include "terminal-util.h" +#include "utmp-wtmp.h" int manager_get_session_from_creds(Manager *m, sd_bus_message *message, const char *name, sd_bus_error *error, Session **ret) { _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL; @@ -1800,6 +1801,7 @@ static int manager_scheduled_shutdown_handler( static int method_schedule_shutdown(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) { Manager *m = userdata; + _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL; const char *action_multiple_sessions = NULL; const char *action_ignore_inhibit = NULL; const char *action = NULL; @@ -1857,6 +1859,24 @@ static int method_schedule_shutdown(sd_bus *bus, sd_bus_message *message, void * m->scheduled_shutdown_timeout = elapse; + r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_AUGMENT|SD_BUS_CREDS_TTY|SD_BUS_CREDS_UID, &creds); + if (r >= 0) { + const char *tty; + + (void) sd_bus_creds_get_uid(creds, &m->scheduled_shutdown_uid); + (void) sd_bus_creds_get_tty(creds, &tty); + + r = free_and_strdup(&m->scheduled_shutdown_tty, tty); + if (r < 0) { + m->scheduled_shutdown_timeout_source = sd_event_source_unref(m->scheduled_shutdown_timeout_source); + return log_oom(); + } + } + + r = manager_setup_wall_message_timer(m); + if (r < 0) + return r; + return sd_bus_reply_method_return(message, NULL); } @@ -1870,10 +1890,27 @@ static int method_cancel_scheduled_shutdown(sd_bus *bus, sd_bus_message *message cancelled = m->scheduled_shutdown_type != NULL; m->scheduled_shutdown_timeout_source = sd_event_source_unref(m->scheduled_shutdown_timeout_source); + m->wall_message_timeout_source = sd_event_source_unref(m->wall_message_timeout_source); free(m->scheduled_shutdown_type); m->scheduled_shutdown_type = NULL; m->scheduled_shutdown_timeout = 0; + if (cancelled) { + _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL; + const char *tty = NULL; + uid_t uid = 0; + int r; + + r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_AUGMENT|SD_BUS_CREDS_TTY|SD_BUS_CREDS_UID, &creds); + if (r >= 0) { + (void) sd_bus_creds_get_uid(creds, &uid); + (void) sd_bus_creds_get_tty(creds, &tty); + } + + utmp_wall("The system shutdown has been cancelled", + lookup_uid(uid), tty, logind_wall_tty_filter, m); + } + return sd_bus_reply_method_return(message, "b", cancelled); } @@ -2275,6 +2312,9 @@ fail: const sd_bus_vtable manager_vtable[] = { SD_BUS_VTABLE_START(0), + SD_BUS_WRITABLE_PROPERTY("EnableWallMessages", "b", NULL, NULL, offsetof(Manager, enable_wall_messages), 0), + SD_BUS_WRITABLE_PROPERTY("WallMessage", "s", NULL, NULL, offsetof(Manager, wall_message), 0), + SD_BUS_PROPERTY("NAutoVTs", "u", NULL, offsetof(Manager, n_autovts), SD_BUS_VTABLE_PROPERTY_CONST), SD_BUS_PROPERTY("KillOnlyUsers", "as", NULL, offsetof(Manager, kill_only_users), SD_BUS_VTABLE_PROPERTY_CONST), SD_BUS_PROPERTY("KillExcludeUsers", "as", NULL, offsetof(Manager, kill_exclude_users), SD_BUS_VTABLE_PROPERTY_CONST), diff --git a/src/login/logind-utmp.c b/src/login/logind-utmp.c new file mode 100644 index 000000000..9bbffe34c --- /dev/null +++ b/src/login/logind-utmp.c @@ -0,0 +1,182 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2015 Daniel Mack + + 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 . +***/ + +#include +#include +#include +#include + +#include "sd-messages.h" +#include "strv.h" +#include "special.h" +#include "unit-name.h" +#include "audit.h" +#include "bus-util.h" +#include "bus-error.h" +#include "bus-common-errors.h" +#include "logind.h" +#include "formats-util.h" +#include "utmp-wtmp.h" + +_const_ static usec_t when_wall(usec_t n, usec_t elapse) { + + usec_t left; + unsigned int i; + static const int wall_timers[] = { + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, + 25, 40, 55, 70, 100, 130, 150, 180, + }; + + /* If the time is already passed, then don't announce */ + if (n >= elapse) + return 0; + + left = elapse - n; + + for (i = 1; i < ELEMENTSOF(wall_timers); i++) + if (wall_timers[i] * USEC_PER_MINUTE >= left) + return left - wall_timers[i-1] * USEC_PER_MINUTE; + + return left % USEC_PER_HOUR; +} + +bool logind_wall_tty_filter(const char *tty, void *userdata) { + + Manager *m = userdata; + + assert(m); + + if (!startswith(tty, "/dev/")) + return true; + + return !streq(tty + 5, m->scheduled_shutdown_tty); +} + +static int warn_wall(Manager *m, usec_t n) { + char date[FORMAT_TIMESTAMP_MAX] = {}; + _cleanup_free_ char *l = NULL; + usec_t left; + int r; + + assert(m); + + if (!m->enable_wall_messages) + return 0; + + left = m->scheduled_shutdown_timeout > n; + + r = asprintf(&l, "%s%sThe system is going down for %s %s%s!", + strempty(m->wall_message), + isempty(m->wall_message) ? "" : "\n", + m->scheduled_shutdown_type, + left ? "at " : "NOW", + left ? format_timestamp(date, sizeof(date), m->scheduled_shutdown_timeout) : ""); + if (r < 0) { + log_oom(); + return 0; + } + + utmp_wall(l, lookup_uid(m->scheduled_shutdown_uid), + m->scheduled_shutdown_tty, logind_wall_tty_filter, m); + + return 1; +} + +static int wall_message_timeout_handler( + sd_event_source *s, + uint64_t usec, + void *userdata) { + + Manager *m = userdata; + usec_t n, next; + int r; + + assert(m); + assert(s == m->wall_message_timeout_source); + + n = now(CLOCK_REALTIME); + + r = warn_wall(m, n); + if (r == 0) + return 0; + + next = when_wall(n, m->scheduled_shutdown_timeout); + if (next > 0) { + r = sd_event_source_set_time(s, n + next); + if (r < 0) + return log_error_errno(r, "sd_event_source_set_time() failed. %m\n"); + + r = sd_event_source_set_enabled(s, SD_EVENT_ONESHOT); + if (r < 0) + return log_error_errno(r, "sd_event_source_set_enabled() failed. %m\n"); + } + + return 0; +} + +int manager_setup_wall_message_timer(Manager *m) { + + usec_t n, elapse; + int r; + + assert(m); + + n = now(CLOCK_REALTIME); + elapse = m->scheduled_shutdown_timeout; + + /* wall message handling */ + + if (isempty(m->scheduled_shutdown_type)) { + warn_wall(m, n); + return 0; + } + + if (elapse < n) + return 0; + + /* Warn immediately if less than 15 minutes are left */ + if (elapse - n < 15 * USEC_PER_MINUTE) { + r = warn_wall(m, n); + if (r == 0) + return 0; + } + + elapse = when_wall(n, elapse); + if (elapse == 0) + return 0; + + if (m->wall_message_timeout_source) { + r = sd_event_source_set_time(m->wall_message_timeout_source, n + elapse); + if (r < 0) + return log_error_errno(r, "sd_event_source_set_time() failed. %m\n"); + + r = sd_event_source_set_enabled(m->wall_message_timeout_source, SD_EVENT_ONESHOT); + if (r < 0) + return log_error_errno(r, "sd_event_source_set_enabled() failed. %m\n"); + } else { + r = sd_event_add_time(m->event, &m->wall_message_timeout_source, + CLOCK_REALTIME, n + elapse, 0, wall_message_timeout_handler, m); + if (r < 0) + return log_error_errno(r, "sd_event_add_time() failed. %m\n"); + } + + return 0; +} diff --git a/src/login/logind.c b/src/login/logind.c index 3a4afdd26..0d96bbdaa 100644 --- a/src/login/logind.c +++ b/src/login/logind.c @@ -145,6 +145,7 @@ static void manager_free(Manager *m) { sd_event_source_unref(m->idle_action_event_source); sd_event_source_unref(m->inhibit_timeout_source); sd_event_source_unref(m->scheduled_shutdown_timeout_source); + sd_event_source_unref(m->wall_message_timeout_source); sd_event_source_unref(m->console_active_event_source); sd_event_source_unref(m->udev_seat_event_source); @@ -178,6 +179,8 @@ static void manager_free(Manager *m) { strv_free(m->kill_exclude_users); free(m->scheduled_shutdown_type); + free(m->scheduled_shutdown_tty); + free(m->wall_message); free(m->action_job); free(m); } diff --git a/src/login/logind.h b/src/login/logind.h index 6fc77d1ca..906c8ba40 100644 --- a/src/login/logind.h +++ b/src/login/logind.h @@ -95,6 +95,12 @@ struct Manager { char *scheduled_shutdown_type; usec_t scheduled_shutdown_timeout; sd_event_source *scheduled_shutdown_timeout_source; + uid_t scheduled_shutdown_uid; + char *scheduled_shutdown_tty; + + char *wall_message; + unsigned enable_wall_messages; + sd_event_source *wall_message_timeout_source; sd_event_source *idle_action_event_source; usec_t idle_action_usec; @@ -171,3 +177,6 @@ int config_parse_tmpfs_size(const char *unit, const char *filename, unsigned lin int manager_get_session_from_creds(Manager *m, sd_bus_message *message, const char *name, sd_bus_error *error, Session **ret); int manager_get_user_from_creds(Manager *m, sd_bus_message *message, uid_t uid, sd_bus_error *error, User **ret); int manager_get_seat_from_creds(Manager *m, sd_bus_message *message, const char *name, sd_bus_error *error, Seat **ret); + +int manager_setup_wall_message_timer(Manager *m); +bool logind_wall_tty_filter(const char *tty, void *userdata); -- 2.30.2