From 736efc6b1ba8e7aabba96b5dc726aad61c2781ba Mon Sep 17 00:00:00 2001
From: Jakub Filak <jfilak@redhat.com>
Date: Tue, 24 Mar 2015 20:48:33 +0100
Subject: [PATCH] dbus: add new method to test existence of an element

It is sometimes necessary to check if some elemen exist, so this method
should be fast as much as it is possible to do this task over DBus.

I was thinking about calling the GetInfo method with a single element
but I refused this idea as it is inherently overcomplicated and error
prone.

Related: #1224984

Signed-off-by: Jakub Filak <jfilak@redhat.com>

Conflicts:
	doc/problems-service/org.freedesktop.Problems.xml.in
---
 .../org.freedesktop.Problems.xml.in                | 28 ++++++++++++++
 src/dbus/abrt-dbus.c                               | 44 ++++++++++++++++++++++
 2 files changed, 72 insertions(+)

diff --git a/doc/problems-service/org.freedesktop.Problems.xml.in b/doc/problems-service/org.freedesktop.Problems.xml.in
index 705b286..2bf8c32 100644
--- a/doc/problems-service/org.freedesktop.Problems.xml.in
+++ b/doc/problems-service/org.freedesktop.Problems.xml.in
@@ -253,6 +253,34 @@ for prblmid in problems.GetProblems():
                 </arg>
             </method>
 
+            <method name='TestElementExists'>
+                <tp:docstring>Checks whether the element exists.</tp:docstring>
+
+                <arg type='s' name='problem_dir' direction='in'>
+                    <tp:docstring>An identifier of problem.</tp:docstring>
+                </arg>
+
+                <arg type='s' name='name' direction='in'>
+                    <tp:docstring>A name of checked element.</tp:docstring>
+                </arg>
+
+                <arg type='b' name='response' direction='out'>
+                    <tp:docstring>True if the element exists; otherwise false.</tp:docstring>
+                </arg>
+            </method>
+
+            <method name='GetProblemData'>"
+                <tp:docstring>Returns problem's data.</tp:docstring>
+
+                <arg type='s' name='problem_dir' direction='in'>
+                    <tp:docstring>An identifier of problem.</tp:docstring>
+                </arg>
+
+                <arg type='a{sits}' name='problem_data' direction='out'>
+                    <tp:docstring>A dictionary where keys are element names and values are triplets (element libreport flags, element size, element contents).</tp:docstring>
+                </arg>
+            </method>
+
             <method name='ChownProblemDir'>
                 <tp:docstring>Assures ownership of a specified problem for the caller.</tp:docstring>
 
diff --git a/src/dbus/abrt-dbus.c b/src/dbus/abrt-dbus.c
index 335c234..173cec4 100644
--- a/src/dbus/abrt-dbus.c
+++ b/src/dbus/abrt-dbus.c
@@ -49,6 +49,11 @@ static const gchar introspection_xml[] =
   "      <arg type='s' name='problem_dir' direction='in'/>"
   "      <arg type='s' name='name' direction='in'/>"
   "    </method>"
+  "    <method name='TestElementExists'>"
+  "      <arg type='s' name='problem_dir' direction='in'/>"
+  "      <arg type='s' name='name' direction='in'/>"
+  "      <arg type='b' name='response' direction='out'/>"
+  "    </method>"
   "    <method name='GetProblemData'>"
   "      <arg type='s' name='problem_dir' direction='in'/>"
   "      <arg type='a{s(its)}' name='problem_data' direction='out'/>"
@@ -781,6 +786,45 @@ static void handle_method_call(GDBusConnection *connection,
         return;
     }
 
+    if (g_strcmp0(method_name, "TestElementExists") == 0)
+    {
+        const char *problem_id;
+        const char *element;
+
+        g_variant_get(parameters, "(&s&s)", &problem_id, &element);
+
+
+        struct dump_dir *dd = dd_opendir(problem_id, DD_OPEN_READONLY);
+        if (!dd)
+        {
+            log_notice("Can't access the problem '%s'", problem_id);
+            g_dbus_method_invocation_return_dbus_error(invocation,
+                                    "org.freedesktop.problems.Failure",
+                                    _("Can't access the problem"));
+            return;
+        }
+
+        int ddstat = dump_dir_stat_for_uid(problem_id, caller_uid);
+        if ((ddstat & DD_STAT_ACCESSIBLE_BY_UID) == 0 &&
+                polkit_check_authorization_dname(caller, "org.freedesktop.problems.getall") != PolkitYes)
+        {
+            dd_close(dd);
+            log_notice("Unauthorized access : '%s'", problem_id);
+            g_dbus_method_invocation_return_dbus_error(invocation,
+                                              "org.freedesktop.problems.AuthFailure",
+                                              _("Not Authorized"));
+            return;
+        }
+
+        int ret = dd_exist(dd, element);
+        dd_close(dd);
+
+        GVariant *response = g_variant_new("(b)", ret);
+        g_dbus_method_invocation_return_value(invocation, response);
+
+        return;
+    }
+
     if (g_strcmp0(method_name, "DeleteProblem") == 0)
     {
         /* Dbus parameters are always tuples.
-- 
2.4.3