From: Kay Sievers <kay@vrfy.org>
Date: Mon, 19 May 2014 10:19:49 +0900
Subject: [PATCH] 0.113: sessionmonitor-systemd: prepare for D-Bus "user bus"
 model

In the D-Bus "user bus" model, all sessions of a user share the same
D-Bus instance, a polkit requesting process might live outside the
login session which registered the user's polkit agent.

In case a polkit requesting process is not part of the user's login
session, we ask systemd-logind for the user's "display" session
instead.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=78905
Bug-Debian: https://bugs.debian.org/779988
Applied-upstream: 0.113, commit:a68f5dfd7662767b7b9822090b70bc5bd145c50c
[smcv: backport configure.ac changes; fail with #error if the required
API is not found]

Imported from policykit-1_0.105-25.debian.tar.xz

Signed-off-by: Michael Olbrich <m.olbrich@pengutronix.de>
---
 configure.ac                                  |  4 +++
 .../polkitbackendsessionmonitor-systemd.c     | 29 +++++++++++++++----
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/configure.ac b/configure.ac
index f4a0c4177fbf..aa2760f90606 100644
--- a/configure.ac
+++ b/configure.ac
@@ -165,6 +165,10 @@ if test "$enable_systemd" != "no"; then
                     have_systemd=no)
   if test "$have_systemd" = "yes"; then
     SESSION_TRACKING=systemd
+    save_LIBS=$LIBS
+    LIBS=$SYSTEMD_LIBS
+    AC_CHECK_FUNCS(sd_uid_get_display)
+    LIBS=$save_LIBS
   else
     if test "$enable_systemd" = "yes"; then
       AC_MSG_ERROR([systemd support requested but libsystemd-login1 library not found])
diff --git a/src/polkitbackend/polkitbackendsessionmonitor-systemd.c b/src/polkitbackend/polkitbackendsessionmonitor-systemd.c
index 756b728ab952..ebd05cea45dc 100644
--- a/src/polkitbackend/polkitbackendsessionmonitor-systemd.c
+++ b/src/polkitbackend/polkitbackendsessionmonitor-systemd.c
@@ -318,6 +318,9 @@ polkit_backend_session_monitor_get_session_for_subject (PolkitBackendSessionMoni
   PolkitSubject *session = NULL;
   char *session_id = NULL;
   pid_t pid;
+#if HAVE_SD_UID_GET_DISPLAY
+  uid_t uid;
+#endif
 
   if (POLKIT_IS_UNIX_PROCESS (subject))
     process = POLKIT_UNIX_PROCESS (subject); /* We already have a process */
@@ -338,16 +341,32 @@ polkit_backend_session_monitor_get_session_for_subject (PolkitBackendSessionMoni
                    g_type_name (G_TYPE_FROM_INSTANCE (subject)));
     }
 
-  /* Now do process -> pid -> session */
+  /* Now do process -> pid -> same session */
   g_assert (process != NULL);
   pid = polkit_unix_process_get_pid (process);
 
-  if (sd_pid_get_session (pid, &session_id) < 0)
+  if (sd_pid_get_session (pid, &session_id) >= 0)
+    {
+      session = polkit_unix_session_new (session_id);
+      goto out;
+    }
+
+#if HAVE_SD_UID_GET_DISPLAY
+  /* Now do process -> uid -> graphical session (systemd version 213)*/
+  if (sd_pid_get_owner_uid (pid, &uid) < 0)
     goto out;
-  
-  session = polkit_unix_session_new (session_id);
-  free (session_id);
+
+  if (sd_uid_get_display (uid, &session_id) >= 0)
+    {
+      session = polkit_unix_session_new (session_id);
+      goto out;
+    }
+#else
+#error Debian should have sd_uid_get_display()
+#endif
+
  out:
+  free (session_id);
   if (tmp_process) g_object_unref (tmp_process);
   return session;
 }