Add pkttyagent(1) helper

This came up while working on

 https://bugzilla.redhat.com/show_bug.cgi?id=804088

and is useful for example if it's not suitable or appropriate to link
against the polkit libraries.

Signed-off-by: David Zeuthen <davidz@redhat.com>

2 files changed, 250 insertions, 1 deletions

diff --git a/src/programs/Makefile.am b/src/programs/Makefile.am
index c260dee..bc1b5a8 100644
--- a/src/programs/Makefile.am
+++ b/src/programs/Makefile.am
@@ -17,7 +17,7 @@ INCLUDES =                                              	\
 
 # ----------------------------------------------------------------------------------------------------
 
-bin_PROGRAMS = pkexec pkcheck pkaction
+bin_PROGRAMS = pkexec pkcheck pkaction pkttyagent
 
 # ----------------------------------------------------------------------------------------------------
 
@@ -50,6 +50,20 @@ pkcheck_LDADD =  	                      				\
 
 # ----------------------------------------------------------------------------------------------------
 
+pkttyagent_SOURCES = pkttyagent.c
+
+pkttyagent_CFLAGS =                             			\
+	$(GLIB_CFLAGS)							\
+	$(NULL)
+
+pkttyagent_LDADD =  	                      				\
+	$(GLIB_LIBS)							\
+	$(top_builddir)/src/polkit/libpolkit-gobject-1.la		\
+	$(top_builddir)/src/polkitagent/libpolkit-agent-1.la		\
+	$(NULL)
+
+# ----------------------------------------------------------------------------------------------------
+
 pkaction_SOURCES = pkaction.c
 
 pkaction_CFLAGS =                             				\
diff --git a/src/programs/pkttyagent.c b/src/programs/pkttyagent.c
new file mode 100644
index 0000000..1c170f4
--- /dev/null
+++ b/src/programs/pkttyagent.c
@@ -0,0 +1,235 @@
+/*
+ * Copyright (C) 2009-2012 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General
+ * Public License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Author: David Zeuthen <davidz@redhat.com>
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include <stdio.h>
+#include <polkit/polkit.h>
+#define POLKIT_AGENT_I_KNOW_API_IS_SUBJECT_TO_CHANGE
+#include <polkitagent/polkitagent.h>
+
+static void
+usage (int argc, char *argv[])
+{
+  GError *error;
+
+  error = NULL;
+  if (!g_spawn_command_line_sync ("man pkttyagent",
+                                  NULL,
+                                  NULL,
+                                  NULL,
+                                  &error))
+    {
+      g_printerr ("Cannot show manual page: %s (%s, %d)\n",
+                  error->message, g_quark_to_string (error->domain), error->code);
+      g_error_free (error);
+    }
+}
+
+
+int
+main (int argc, char *argv[])
+{
+  gboolean opt_show_help = FALSE;
+  gboolean opt_show_version = FALSE;
+  PolkitAuthority *authority = NULL;
+  PolkitSubject *subject = NULL;
+  gpointer local_agent_handle = NULL;
+  PolkitAgentListener *listener = NULL;
+  GError *error;
+  GMainLoop *loop = NULL;
+  guint n;
+  guint ret = 126;
+  gint notify_fd = -1;
+
+  g_type_init ();
+
+  for (n = 1; n < (guint) argc; n++)
+    {
+      if (g_strcmp0 (argv[n], "--help") == 0)
+        {
+          opt_show_help = TRUE;
+        }
+      else if (g_strcmp0 (argv[n], "--version") == 0)
+        {
+          opt_show_version = TRUE;
+        }
+      else if (g_strcmp0 (argv[n], "--notify-fd") == 0)
+        {
+          n++;
+          if (n >= (guint) argc)
+            {
+              usage (argc, argv);
+              goto out;
+            }
+
+          if (sscanf (argv[n], "%i", &notify_fd) != 1)
+            {
+              usage (argc, argv);
+              goto out;
+            }
+        }
+      else if (g_strcmp0 (argv[n], "--process") == 0 || g_strcmp0 (argv[n], "-p") == 0)
+        {
+          gint pid;
+          guint64 pid_start_time;
+
+          n++;
+          if (n >= (guint) argc)
+            {
+              usage (argc, argv);
+              goto out;
+            }
+
+          if (sscanf (argv[n], "%i,%" G_GUINT64_FORMAT, &pid, &pid_start_time) == 2)
+            {
+              subject = polkit_unix_process_new_full (pid, pid_start_time);
+            }
+          else if (sscanf (argv[n], "%i", &pid) == 1)
+            {
+              subject = polkit_unix_process_new (pid);
+            }
+          else
+            {
+              usage (argc, argv);
+              goto out;
+            }
+        }
+      else if (g_strcmp0 (argv[n], "--system-bus-name") == 0 || g_strcmp0 (argv[n], "-s") == 0)
+        {
+          n++;
+          if (n >= (guint) argc)
+            {
+              usage (argc, argv);
+              goto out;
+            }
+
+          subject = polkit_system_bus_name_new (argv[n]);
+        }
+      else
+        {
+          break;
+        }
+    }
+
+  if (opt_show_help)
+    {
+      usage (argc, argv);
+      ret = 0;
+      goto out;
+    }
+  else if (opt_show_version)
+    {
+      g_print ("pkttyagent version %s\n", PACKAGE_VERSION);
+      ret = 0;
+      goto out;
+    }
+
+  /* Use parent process, if no subject has been specified */
+  if (subject == NULL)
+    {
+      pid_t pid_of_caller;
+      pid_of_caller = getppid ();
+      if (pid_of_caller == 1)
+        {
+          /* getppid() can return 1 if the parent died (meaning that we are reaped
+           * by /sbin/init); In that case we simpy bail.
+           */
+          g_printerr ("Refusing to render service to dead parents.\n");
+          goto out;
+        }
+
+      subject = polkit_unix_process_new_for_owner (pid_of_caller,
+                                                   0, /* 0 means "look up start-time in /proc" */
+                                                   getuid ());
+      /* really double-check the invariants guaranteed by the PolkitUnixProcess class */
+      g_assert (subject != NULL);
+      g_assert (polkit_unix_process_get_pid (POLKIT_UNIX_PROCESS (subject)) == pid_of_caller);
+      g_assert (polkit_unix_process_get_uid (POLKIT_UNIX_PROCESS (subject)) >= 0);
+      g_assert (polkit_unix_process_get_start_time (POLKIT_UNIX_PROCESS (subject)) > 0);
+    }
+
+  error = NULL;
+  authority = polkit_authority_get_sync (NULL /* GCancellable* */, &error);
+  if (authority == NULL)
+    {
+      g_printerr ("Error getting authority: %s (%s, %d)\n",
+                  error->message, g_quark_to_string (error->domain), error->code);
+      g_error_free (error);
+      ret = 127;
+      goto out;
+    }
+
+  error = NULL;
+  /* this will fail if we can't find a controlling terminal */
+  listener = polkit_agent_text_listener_new (NULL, &error);
+  if (listener == NULL)
+    {
+      g_printerr ("Error creating textual authentication agent: %s (%s, %d)\n",
+                  error->message, g_quark_to_string (error->domain), error->code);
+      g_error_free (error);
+      ret = 127;
+      goto out;
+    }
+  local_agent_handle = polkit_agent_listener_register (listener,
+                                                       POLKIT_AGENT_REGISTER_FLAGS_RUN_IN_THREAD,
+                                                       subject,
+                                                       NULL, /* object_path */
+                                                       NULL, /* GCancellable */
+                                                       &error);
+  g_object_unref (listener);
+  if (local_agent_handle == NULL)
+    {
+      g_printerr ("Error registering authentication agent: %s (%s, %d)\n",
+                  error->message, g_quark_to_string (error->domain), error->code);
+      g_error_free (error);
+      goto out;
+    }
+
+  if (notify_fd != -1)
+    {
+      if (close (notify_fd) != 0)
+        {
+          g_printerr ("Error closing notify-fd %d: %m\n", notify_fd);
+          goto out;
+        }
+    }
+
+  loop = g_main_loop_new (NULL, FALSE);
+  g_main_loop_run (loop);
+
+ out:
+  if (loop != NULL)
+    g_main_loop_unref (loop);
+
+  if (local_agent_handle != NULL)
+    polkit_agent_listener_unregister (local_agent_handle);
+
+  if (subject != NULL)
+    g_object_unref (subject);
+
+  if (authority != NULL)
+    g_object_unref (authority);
+
+  return ret;
+}