logind: add new session type "web" for PAM web clients, such as cockpit

[elogind.git] / src / login / logind.c

diff --git a/src/login/logind.c b/src/login/logind.c
index 7a7bd97150864739fd66e3f07980907f7e0b3791..8ec810535732a7dab589a1a9de9c43d31cde363c 100644 (file)
--- a/src/login/logind.c
+++ b/src/login/logind.c
@@ -720,6 +720,47 @@ static int manager_connect_bus(Manager *m) {
         return 0;
 }
 
+static int manager_vt_switch(sd_event_source *src, const struct signalfd_siginfo *si, void *data) {
+        Manager *m = data;
+        Session *active, *iter;
+
+        /*
+         * We got a VT-switch signal and we have to acknowledge it immediately.
+         * Preferably, we'd just use m->seat0->active->vtfd, but unfortunately,
+         * old user-space might run multiple sessions on a single VT, *sigh*.
+         * Therefore, we have to iterate all sessions and find one with a vtfd
+         * on the requested VT.
+         * As only VTs with active controllers have VT_PROCESS set, our current
+         * notion of the active VT might be wrong (for instance if the switch
+         * happens while we setup VT_PROCESS). Therefore, read the current VT
+         * first and then use s->active->vtnr as reference. Note that this is
+         * not racy, as no further VT-switch can happen as long as we're in
+         * synchronous VT_PROCESS mode.
+         */
+
+        assert(m->seat0);
+        seat_read_active_vt(m->seat0);
+
+        active = m->seat0->active;
+        if (!active || active->vtnr < 1) {
+                log_warning("Received VT_PROCESS signal without a registered session on that VT.");
+                return 0;
+        }
+
+        if (active->vtfd >= 0) {
+                ioctl(active->vtfd, VT_RELDISP, 1);
+        } else {
+                LIST_FOREACH(sessions_by_seat, iter, m->seat0->sessions) {
+                        if (iter->vtnr == active->vtnr && iter->vtfd >= 0) {
+                                ioctl(iter->vtfd, VT_RELDISP, 1);
+                                break;
+                        }
+                }
+        }
+
+        return 0;
+}
+
 static int manager_connect_console(Manager *m) {
         int r;
 
@@ -750,6 +791,34 @@ static int manager_connect_console(Manager *m) {
                 return r;
         }
 
+        /*
+         * SIGRTMIN is used as global VT-release signal, SIGRTMIN + 1 is used
+         * as VT-acquire signal. We ignore any acquire-events (yes, we still
+         * have to provide a valid signal-number for it!) and acknowledge all
+         * release events immediately.
+         */
+
+        if (SIGRTMIN + 1 > SIGRTMAX) {
+                log_error("Not enough real-time signals available: %u-%u", SIGRTMIN, SIGRTMAX);
+                return -EINVAL;
+        }
+
+        r = ignore_signals(SIGRTMIN + 1, -1);
+        if (r < 0) {
+                log_error("Cannot ignore SIGRTMIN + 1: %s", strerror(-r));
+                return r;
+        }
+
+        r = sigprocmask_many(SIG_BLOCK, SIGRTMIN, -1);
+        if (r < 0) {
+                log_error("Cannot block SIGRTMIN: %s", strerror(-r));
+                return r;
+        }
+
+        r = sd_event_add_signal(m->event, NULL, SIGRTMIN, manager_vt_switch, m);
+        if (r < 0)
+                return r;
+
         return 0;
 }
 
@@ -1097,27 +1166,12 @@ int manager_run(Manager *m) {
 }
 
 static int manager_parse_config_file(Manager *m) {
-        static const char fn[] = "/etc/systemd/logind.conf";
-        _cleanup_fclose_ FILE *f = NULL;
-        int r;
-
         assert(m);
 
-        f = fopen(fn, "re");
-        if (!f) {
-                if (errno == ENOENT)
-                        return 0;
-
-                log_warning("Failed to open configuration file %s: %m", fn);
-                return -errno;
-        }
-
-        r = config_parse(NULL, fn, f, "Login\0", config_item_perf_lookup,
-                         (void*) logind_gperf_lookup, false, false, m);
-        if (r < 0)
-                log_warning("Failed to parse configuration file: %s", strerror(-r));
-
-        return r;
+        return config_parse(NULL, "/etc/systemd/logind.conf", NULL,
+                            "Login\0",
+                            config_item_perf_lookup, logind_gperf_lookup,
+                            false, false, true, m);
 }
 
 int main(int argc, char *argv[]) {