diff options
Diffstat (limited to 'src/update-utmp/update-utmp.c')
| -rw-r--r-- | src/update-utmp/update-utmp.c | 251 |
1 files changed, 251 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..59c49f2 --- /dev/null +++ b/src/update-utmp/update-utmp.c @@ -0,0 +1,251 @@ +/* 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-util.h" +#include "format-util.h" +#include "log.h" +#include "macro.h" +#include "main-func.h" +#include "process-util.h" +#include "special.h" +#include "stdio-util.h" +#include "strv.h" +#include "unit-name.h" +#include "util.h" +#include "utmp-wtmp.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 = -1; +#endif +} + +static usec_t get_startup_time(Context *c) { + _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; + usec_t t = 0; + int r; + + assert(c); + + r = sd_bus_get_property_trivial( + c->bus, + "org.freedesktop.systemd1", + "/org/freedesktop/systemd1", + "org.freedesktop.systemd1.Manager", + "UserspaceTimestamp", + &error, + 't', &t); + if (r < 0) { + log_error_errno(r, "Failed to get timestamp: %s", bus_error_message(&error, r)); + return 0; + } + + return t; +} + +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 }, + }; + + _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; + int r; + + assert(c); + + for (size_t i = 0; i < ELEMENTSOF(table); i++) { + _cleanup_free_ char *state = NULL, *path = NULL; + + path = unit_dbus_path_from_name(table[i].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 < 0) + return log_warning_errno(r, "Failed to get state: %s", bus_error_message(&error, r)); + + if (STR_IN_SET(state, "active", "reloading")) + return table[i].runlevel; + } + + return 0; +} + +static int on_reboot(Context *c) { + int r = 0, q; + usec_t t; + + assert(c); + + /* 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) + r = log_error_errno(errno, "Failed to send audit message: %m"); +#endif + + /* If this call fails it will return 0, which + * utmp_put_reboot() will then fix to the current time */ + t = get_startup_time(c); + + q = utmp_put_reboot(t); + if (q < 0) + r = log_error_errno(q, "Failed to write utmp record: %m"); + + return r; +} + +static int on_shutdown(Context *c) { + int r = 0, q; + + assert(c); + + /* We started shut-down, 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_SHUTDOWN, "", "systemd-update-utmp", NULL, NULL, NULL, 1) < 0 && + errno != EPERM) + r = log_error_errno(errno, "Failed to send audit message: %m"); +#endif + + q = utmp_put_shutdown(); + if (q < 0) + r = log_error_errno(q, "Failed to write utmp record: %m"); + + return r; +} + +static int on_runlevel(Context *c) { + int r = 0, q, previous, runlevel; + + assert(c); + + /* We finished changing runlevel, so let's write the + * utmp record and send the audit msg */ + + /* First, get last runlevel */ + q = utmp_get_runlevel(&previous, NULL); + + if (q < 0) { + if (!IN_SET(q, -ESRCH, -ENOENT)) + return log_error_errno(q, "Failed to get current runlevel: %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 new 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) + r = log_error_errno(errno, "Failed to send audit message: %m"); + } +#endif + + q = utmp_put_runlevel(runlevel, previous); + if (q < 0 && !IN_SET(q, -ESRCH, -ENOENT)) + return log_error_errno(q, "Failed to write utmp record: %m"); + + return r; +} + +static int run(int argc, char *argv[]) { + _cleanup_(context_clear) Context c = { +#if HAVE_AUDIT + .audit_fd = -1 +#endif + }; + int r; + + if (argc != 2) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "This program requires one argument."); + + log_setup_service(); + + 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_ERR, + errno, "Failed to connect to audit log: %m"); +#endif + r = bus_connect_system_systemd(&c.bus); + if (r < 0) + return log_error_errno(r, "Failed to get D-Bus connection: %m"); + + if (streq(argv[1], "reboot")) + return on_reboot(&c); + if (streq(argv[1], "shutdown")) + return on_shutdown(&c); + if (streq(argv[1], "runlevel")) + return on_runlevel(&c); + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Unknown command %s", argv[1]); +} + +DEFINE_MAIN_FUNCTION(run); |