audit,utmp: implement audit logic and rip utmp stuff out of the main daemon and into a helper binary

1 files changed, 410 insertions, 0 deletions

diff --git a/src/update-utmp.c b/src/update-utmp.c
new file mode 100644
index 0000000000..e64a819aa4
--- /dev/null
+++ b/src/update-utmp.c
@@ -0,0 +1,410 @@
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+/***
+  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 General Public License as published by
+  the Free Software Foundation; either version 2 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
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+#include <libaudit.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <dbus/dbus.h>
+
+#include "log.h"
+#include "macro.h"
+#include "util.h"
+#include "special.h"
+#include "utmp-wtmp.h"
+#include "dbus-common.h"
+
+typedef struct Context {
+        DBusConnection *bus;
+#ifdef HAVE_AUDIT
+        int audit_fd;
+#endif
+} Context;
+
+static usec_t get_startup_time(Context *c) {
+        const char
+                *interface = "org.freedesktop.systemd1.Manager",
+                *property = "StartupTimestamp";
+
+        DBusError error;
+        usec_t t = 0;
+        DBusMessage *m = NULL, *reply = NULL;
+        DBusMessageIter iter, sub;
+
+        dbus_error_init(&error);
+
+        assert(c);
+
+        if (!(m = dbus_message_new_method_call(
+                              "org.freedesktop.systemd1",
+                              "/org/freedesktop/systemd1",
+                              "org.freedesktop.DBus.Properties",
+                              "Get"))) {
+                log_error("Could not allocate message.");
+                goto finish;
+        }
+
+        if (!dbus_message_append_args(m,
+                                      DBUS_TYPE_STRING, &interface,
+                                      DBUS_TYPE_STRING, &property,
+                                      DBUS_TYPE_INVALID)) {
+                log_error("Could not append arguments to message.");
+                goto finish;
+        }
+
+        if (!(reply = dbus_connection_send_with_reply_and_block(c->bus, m, -1, &error))) {
+                log_error("Failed to send command: %s", error.message);
+                goto finish;
+        }
+
+        if (!dbus_message_iter_init(reply, &iter) ||
+            dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_VARIANT)  {
+                log_error("Failed to parse reply.");
+                goto finish;
+        }
+
+        dbus_message_iter_recurse(&iter, &sub);
+
+        if (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_UINT64)  {
+                log_error("Failed to parse reply.");
+                goto finish;
+        }
+
+        dbus_message_iter_get_basic(&sub, &t);
+
+finish:
+        if (m)
+                dbus_message_unref(m);
+
+        if (reply)
+                dbus_message_unref(reply);
+
+        dbus_error_free(&error);
+
+        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 */
+                { '0', SPECIAL_POWEROFF_TARGET },
+                { '6', SPECIAL_REBOOT_TARGET },
+                { '5', SPECIAL_RUNLEVEL5_TARGET },
+                { '4', SPECIAL_RUNLEVEL4_TARGET },
+                { '3', SPECIAL_RUNLEVEL3_TARGET },
+                { '2', SPECIAL_RUNLEVEL2_TARGET },
+                { '1', SPECIAL_RESCUE_TARGET },
+        };
+        const char
+                *interface = "org.freedesktop.systemd1.Unit",
+                *property = "ActiveState";
+
+        DBusMessage *m = NULL, *reply = NULL;
+        int r = 0;
+        unsigned i;
+        DBusError error;
+
+        assert(c);
+
+        dbus_error_init(&error);
+
+        for (i = 0; i < ELEMENTSOF(table); i++) {
+                const char *path = NULL, *state;
+                DBusMessageIter iter, sub;
+
+                if (!(m = dbus_message_new_method_call(
+                                      "org.freedesktop.systemd1",
+                                      "/org/freedesktop/systemd1",
+                                      "org.freedesktop.systemd1.Manager",
+                                      "GetUnit"))) {
+                        log_error("Could not allocate message.");
+                        r = -ENOMEM;
+                        goto finish;
+                }
+
+                if (!dbus_message_append_args(m,
+                                              DBUS_TYPE_STRING, &table[i].special,
+                                              DBUS_TYPE_INVALID)) {
+                        log_error("Could not append arguments to message.");
+                        r = -ENOMEM;
+                        goto finish;
+                }
+
+                if (!(reply = dbus_connection_send_with_reply_and_block(c->bus, m, -1, &error))) {
+                        dbus_error_free(&error);
+                        continue;
+                }
+
+                if (!dbus_message_get_args(reply, &error,
+                                           DBUS_TYPE_OBJECT_PATH, &path,
+                                           DBUS_TYPE_INVALID)) {
+                        log_error("Failed to parse reply: %s", error.message);
+                        r = -EIO;
+                        goto finish;
+                }
+
+                dbus_message_unref(m);
+                if (!(m = dbus_message_new_method_call(
+                                      "org.freedesktop.systemd1",
+                                      path,
+                                      "org.freedesktop.DBus.Properties",
+                                      "Get"))) {
+                        log_error("Could not allocate message.");
+                        r = -ENOMEM;
+                        goto finish;
+                }
+
+                if (!dbus_message_append_args(m,
+                                              DBUS_TYPE_STRING, &interface,
+                                              DBUS_TYPE_STRING, &property,
+                                              DBUS_TYPE_INVALID)) {
+                        log_error("Could not append arguments to message.");
+                        r = -ENOMEM;
+                        goto finish;
+                }
+
+                dbus_message_unref(reply);
+                if (!(reply = dbus_connection_send_with_reply_and_block(c->bus, m, -1, &error))) {
+                        log_error("Failed to send command: %s", error.message);
+                        r = -EIO;
+                        goto finish;
+                }
+
+                if (!dbus_message_iter_init(reply, &iter) ||
+                    dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_VARIANT)  {
+                        log_error("Failed to parse reply.");
+                        r = -EIO;
+                        goto finish;
+                }
+
+                dbus_message_iter_recurse(&iter, &sub);
+
+                if (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_STRING)  {
+                        log_error("Failed to parse reply.");
+                        r = -EIO;
+                        goto finish;
+                }
+
+                dbus_message_iter_get_basic(&sub, &state);
+
+                if (streq(state, "active") || streq(state, "reloading"))
+                        r = table[i].runlevel;
+
+                dbus_message_unref(m);
+                dbus_message_unref(reply);
+                m = reply = NULL;
+
+                if (r)
+                        break;
+        }
+
+finish:
+        if (m)
+                dbus_message_unref(m);
+
+        if (reply)
+                dbus_message_unref(reply);
+
+        dbus_error_free(&error);
+
+        return r;
+}
+
+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 */
+
+#ifdef HAVE_AUDIT
+        if (c->audit_fd >= 0)
+                if (audit_log_user_message(c->audit_fd, AUDIT_SYSTEM_BOOT, "", NULL, NULL, NULL, 1) < 0) {
+                        log_error("Failed to send audit message: %m");
+                        r = -errno;
+                }
+#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);
+
+        if ((q = utmp_put_reboot(t)) < 0) {
+                log_error("Failed to write utmp record: %s", strerror(-q));
+                r = q;
+        }
+
+        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 */
+
+#ifdef HAVE_AUDIT
+        if (c->audit_fd >= 0)
+                if (audit_log_user_message(c->audit_fd, AUDIT_SYSTEM_SHUTDOWN, "", NULL, NULL, NULL, 1) < 0) {
+                        log_error("Failed to send audit message: %m");
+                        r = -errno;
+                }
+#endif
+
+        if ((q = utmp_put_shutdown(0)) < 0) {
+                log_error("Failed to write utmp record: %s", strerror(-q));
+                r = q;
+        }
+
+        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 */
+        if ((q = utmp_get_runlevel(&previous, NULL)) < 0) {
+
+                if (q != -ESRCH && q != -ENOENT) {
+                        log_error("Failed to get current runlevel: %s", strerror(-q));
+                        return q;
+                }
+
+                /* Hmm, we didn't find any runlevel, that means we
+                 * have been rebooted */
+                r = on_reboot(c);
+                previous = 0;
+        }
+
+        /* Second get new runlevel */
+        if ((runlevel = get_current_runlevel(c)) < 0)
+                return runlevel;
+
+        if (previous == runlevel)
+                return 0;
+
+#ifdef HAVE_AUDIT
+        if (c->audit_fd >= 0) {
+                char *s = NULL;
+
+                if (asprintf(&s, "old-level=%c new-level=%c", previous, runlevel) < 0)
+                        return -ENOMEM;
+
+                if (audit_log_user_message(c->audit_fd, AUDIT_SYSTEM_RUNLEVEL, s, NULL, NULL, NULL, 1) < 0) {
+                        log_error("Failed to send audit message: %m");
+                        r = -errno;
+                }
+
+                free(s);
+        }
+#endif
+
+        if ((q = utmp_put_runlevel(0, runlevel, previous)) < 0) {
+                log_error("Failed to write utmp record: %s", strerror(-q));
+                r = q;
+        }
+
+        return r;
+}
+
+int main(int argc, char *argv[]) {
+        int r;
+        DBusError error;
+        Context c;
+
+        dbus_error_init(&error);
+
+        zero(c);
+#ifdef HAVE_AUDIT
+        c.audit_fd = -1;
+#endif
+
+        /* if (getppid() != 1) { */
+        /*         log_error("This program should be invoked by init only."); */
+        /*         return 1; */
+        /* } */
+
+        if (argc != 2) {
+                log_error("This program requires one argument.");
+                return 1;
+        }
+
+        log_set_target(LOG_TARGET_SYSLOG_OR_KMSG);
+        log_parse_environment();
+
+#ifdef HAVE_AUDIT
+        if ((c.audit_fd = audit_open()) < 0)
+                log_error("Failed to connect to audit log: %m");
+#endif
+
+        if (bus_connect(DBUS_BUS_SYSTEM, &c.bus, NULL, &error) < 0) {
+                log_error("Failed to get D-Bus connection: %s", error.message);
+                r = -EIO;
+                goto finish;
+        }
+
+        log_info("systemd-update-utmp running as pid %lu", (unsigned long) getpid());
+
+        if (streq(argv[1], "reboot"))
+                r = on_reboot(&c);
+        else if (streq(argv[1], "shutdown"))
+                r = on_shutdown(&c);
+        else if (streq(argv[1], "runlevel"))
+                r = on_runlevel(&c);
+        else {
+                log_error("Unknown command %s", argv[1]);
+                r = -EINVAL;
+        }
+
+        log_info("systemd-update-utmp stopped as pid %lu", (unsigned long) getpid());
+finish:
+
+#ifdef HAVE_AUDIT
+        if (c.audit_fd >= 0)
+                audit_close(c.audit_fd);
+#endif
+
+        if (c.bus) {
+               dbus_connection_close(c.bus);
+               dbus_connection_unref(c.bus);
+        }
+
+        dbus_error_free(&error);
+        dbus_shutdown();
+
+        return r < 0 ? 1 : 0;
+}