Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 266 insertions, 0 deletions

diff --git a/src/update-utmp/update-utmp.c b/src/update-utmp/update-utmp.c
new file mode 100644
index 0000000..4ee935e
--- /dev/null
+++ b/src/update-utmp/update-utmp.c
@@ -0,0 +1,266 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#if HAVE_AUDIT
+#include <libaudit.h>
+#endif
+
+#include "sd-bus.h"
+
+#include "alloc-util.h"
+#include "bus-error.h"
+#include "bus-locator.h"
+#include "bus-util.h"
+#include "format-util.h"
+#include "log.h"
+#include "macro.h"
+#include "main-func.h"
+#include "process-util.h"
+#include "random-util.h"
+#include "special.h"
+#include "stdio-util.h"
+#include "strv.h"
+#include "unit-name.h"
+#include "utmp-wtmp.h"
+#include "verbs.h"
+
+typedef struct Context {
+        sd_bus *bus;
+#if HAVE_AUDIT
+        int audit_fd;
+#endif
+} Context;
+
+static void context_clear(Context *c) {
+        assert(c);
+
+        c->bus = sd_bus_flush_close_unref(c->bus);
+#if HAVE_AUDIT
+        if (c->audit_fd >= 0)
+                audit_close(c->audit_fd);
+        c->audit_fd = -EBADF;
+#endif
+}
+
+static int get_startup_monotonic_time(Context *c, usec_t *ret) {
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+        int r;
+
+        assert(c);
+        assert(ret);
+
+        r = bus_get_property_trivial(
+                        c->bus,
+                        bus_systemd_mgr,
+                        "UserspaceTimestampMonotonic",
+                        &error,
+                        't', ret);
+        if (r < 0)
+                return log_warning_errno(r, "Failed to get timestamp, ignoring: %s", bus_error_message(&error, r));
+
+        return 0;
+}
+
+static int get_current_runlevel(Context *c) {
+        static const struct {
+                const int runlevel;
+                const char *special;
+        } table[] = {
+                /* The first target of this list that is active or has a job scheduled wins. We prefer
+                 * runlevels 5 and 3 here over the others, since these are the main runlevels used on Fedora.
+                 * It might make sense to change the order on some distributions. */
+                { '5', SPECIAL_GRAPHICAL_TARGET  },
+                { '3', SPECIAL_MULTI_USER_TARGET },
+                { '1', SPECIAL_RESCUE_TARGET     },
+        };
+        int r;
+
+        assert(c);
+
+        for (unsigned n_attempts = 0;;) {
+                FOREACH_ARRAY(e, table, ELEMENTSOF(table)) {
+                        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+                        _cleanup_free_ char *state = NULL, *path = NULL;
+
+                        path = unit_dbus_path_from_name(e->special);
+                        if (!path)
+                                return log_oom();
+
+                        r = sd_bus_get_property_string(
+                                        c->bus,
+                                        "org.freedesktop.systemd1",
+                                        path,
+                                        "org.freedesktop.systemd1.Unit",
+                                        "ActiveState",
+                                        &error,
+                                        &state);
+                        if ((r == -ENOTCONN ||
+                             sd_bus_error_has_names(&error,
+                                                    SD_BUS_ERROR_NO_REPLY,
+                                                    SD_BUS_ERROR_DISCONNECTED)) &&
+                            ++n_attempts < 64) {
+
+                                /* systemd might have dropped off momentarily, let's not make this an error,
+                                 * and wait some random time. Let's pick a random time in the range 0ms…250ms,
+                                 * linearly scaled by the number of failed attempts. */
+
+                                usec_t usec = random_u64_range(UINT64_C(10) * USEC_PER_MSEC +
+                                                               UINT64_C(240) * USEC_PER_MSEC * n_attempts/64);
+                                log_debug_errno(r, "Failed to get state of %s, retrying after %s: %s",
+                                                e->special, FORMAT_TIMESPAN(usec, USEC_PER_MSEC), bus_error_message(&error, r));
+                                (void) usleep_safe(usec);
+                                goto reconnect;
+                        }
+                        if (r < 0)
+                                return log_warning_errno(r, "Failed to get state of %s: %s", e->special, bus_error_message(&error, r));
+
+                        if (STR_IN_SET(state, "active", "reloading"))
+                                return e->runlevel;
+                }
+
+                return 0;
+
+reconnect:
+                c->bus = sd_bus_flush_close_unref(c->bus);
+                r = bus_connect_system_systemd(&c->bus);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to reconnect to system bus: %m");
+        }
+}
+
+static int on_reboot(int argc, char *argv[], void *userdata) {
+        Context *c = ASSERT_PTR(userdata);
+        usec_t t = 0, boottime;
+        int r, q = 0;
+
+        /* We finished start-up, so let's write the utmp record and send the audit msg. */
+
+#if HAVE_AUDIT
+        if (c->audit_fd >= 0)
+                if (audit_log_user_comm_message(c->audit_fd, AUDIT_SYSTEM_BOOT, "", "systemd-update-utmp", NULL, NULL, NULL, 1) < 0 &&
+                    errno != EPERM)
+                        q = log_error_errno(errno, "Failed to send audit message: %m");
+#endif
+
+        /* If this call fails, then utmp_put_reboot() will fix to the current time. */
+        (void) get_startup_monotonic_time(c, &t);
+        boottime = map_clock_usec(t, CLOCK_MONOTONIC, CLOCK_REALTIME);
+        /* We query the recorded monotonic time here (instead of the system clock CLOCK_REALTIME), even
+         * though we actually want the system clock time. That's because there's a likely chance that the
+         * system clock wasn't set right during early boot. By manually converting the monotonic clock to the
+         * system clock here we can compensate for incorrectly set clocks during early boot. */
+
+        r = utmp_put_reboot(boottime);
+        if (r < 0)
+                return log_error_errno(r, "Failed to write utmp record: %m");
+
+        return q;
+}
+
+static int on_shutdown(int argc, char *argv[], void *userdata) {
+        int r, q = 0;
+
+        /* We started shut-down, so let's write the utmp record and send the audit msg. */
+
+#if HAVE_AUDIT
+        Context *c = ASSERT_PTR(userdata);
+
+        if (c->audit_fd >= 0)
+                if (audit_log_user_comm_message(c->audit_fd, AUDIT_SYSTEM_SHUTDOWN, "", "systemd-update-utmp", NULL, NULL, NULL, 1) < 0 &&
+                    errno != EPERM)
+                        q = log_error_errno(errno, "Failed to send audit message: %m");
+#endif
+
+        r = utmp_put_shutdown();
+        if (r < 0)
+                return log_error_errno(r, "Failed to write utmp record: %m");
+
+        return q;
+}
+
+static int on_runlevel(int argc, char *argv[], void *userdata) {
+        Context *c = ASSERT_PTR(userdata);
+        int r, q = 0, previous, runlevel;
+
+        /* We finished changing runlevel, so let's write the utmp record and send the audit msg. */
+
+        /* First, get last runlevel */
+        r = utmp_get_runlevel(&previous, NULL);
+        if (r < 0) {
+                if (!IN_SET(r, -ESRCH, -ENOENT))
+                        return log_error_errno(r, "Failed to get the last runlevel from utmp: %m");
+
+                previous = 0;
+        }
+
+        /* Secondly, get new runlevel */
+        runlevel = get_current_runlevel(c);
+        if (runlevel < 0)
+                return runlevel;
+        if (runlevel == 0) {
+                log_warning("Failed to get the current runlevel, utmp update skipped.");
+                return 0;
+        }
+
+        if (previous == runlevel)
+                return 0;
+
+#if HAVE_AUDIT
+        if (c->audit_fd >= 0) {
+                char s[STRLEN("old-level=_ new-level=_") + 1];
+
+                xsprintf(s, "old-level=%c new-level=%c",
+                         previous > 0 ? previous : 'N',
+                         runlevel);
+
+                if (audit_log_user_comm_message(c->audit_fd, AUDIT_SYSTEM_RUNLEVEL, s,
+                                                "systemd-update-utmp", NULL, NULL, NULL, 1) < 0 && errno != EPERM)
+                        q = log_error_errno(errno, "Failed to send audit message: %m");
+        }
+#endif
+
+        r = utmp_put_runlevel(runlevel, previous);
+        if (r < 0 && !IN_SET(r, -ESRCH, -ENOENT))
+                return log_error_errno(r, "Failed to write utmp record: %m");
+
+        return q;
+}
+
+static int run(int argc, char *argv[]) {
+        static const Verb verbs[] = {
+                { "reboot",   1, 1, 0, on_reboot   },
+                { "shutdown", 1, 1, 0, on_shutdown },
+                { "runlevel", 1, 1, 0, on_runlevel },
+                {}
+        };
+
+        _cleanup_(context_clear) Context c = {
+#if HAVE_AUDIT
+                .audit_fd = -EBADF,
+#endif
+        };
+        int r;
+
+        log_setup();
+
+        umask(0022);
+
+#if HAVE_AUDIT
+        /* If the kernel lacks netlink or audit support, don't worry about it. */
+        c.audit_fd = audit_open();
+        if (c.audit_fd < 0)
+                log_full_errno(IN_SET(errno, EAFNOSUPPORT, EPROTONOSUPPORT) ? LOG_DEBUG : LOG_WARNING,
+                               errno, "Failed to connect to audit log, ignoring: %m");
+#endif
+        r = bus_connect_system_systemd(&c.bus);
+        if (r < 0)
+                return log_error_errno(r, "Failed to get D-Bus connection: %m");
+
+        return dispatch_verb(argc, argv, verbs, &c);
+}
+
+DEFINE_MAIN_FUNCTION(run);