add interactive_authorization options for buses

Summary:
Pystemd is menat to be used as a library, so it never really implemented the interactive auth that systemd uses, but recently people really want to use it, and since its already there, lets just add it.

see examples/start_transient_unit.py on how to setup interactive auth.

Reviewed By: davide125

Differential Revision: D31773957

fbshipit-source-id: 2cae24cadd3945693515613850c345f9b0d33d83

CHANGES.md

@@ -4,6 +4,10 @@ Changelog
 We annotate all changes here, keep in mind that the high version may not be
 the one you find pypi, but its the one in development.
 
+0.10.0
+=====
+* support for interactive auth.
+
 0.9.0
 =====
 * add initial support for Python 3.9

examples/start_transient_unit.py

@@ -11,6 +11,7 @@
 import shlex
 import time
 
+from pystemd.dbuslib import DBus
 from pystemd.systemd1 import Manager, Unit
 
 
@@ -25,23 +26,24 @@ def start_transient_unit(cmd="/bin/sleep 15"):
         b"ExecStart": [(a_cmd[0], a_cmd, False)],
         b"RemainAfterExit": True,
     }
-
-    with Manager() as manager:
+    # if we need interactive prompts for passwords, we can create our own DBus object.
+    # if we dont need interactive, we would just do `with Manager() as manager:`.
+    with DBus(interactive=True) as bus, Manager(bus=bus) as manager:
         manager.Manager.StartTransientUnit(random_unit_name, b"fail", unit)
 
-    with Unit(random_unit_name) as unit:
-        while True:
-            print(
-                "service `{cmd}` (name={random_unit_name}) has MainPID "
-                "{unit.Service.MainPID}".format(**locals())
-            )
-            if unit.Service.MainPID == 0:
+        with Unit(random_unit_name, bus=bus) as unit:
+            while True:
                 print(
-                    "service finished with "
-                    "{unit.Service.ExecMainStatus}/{unit.Service.Result} "
-                    "will stop it and then... bye".format(**locals())
+                    "service `{cmd}` (name={random_unit_name}) has MainPID "
+                    "{unit.Service.MainPID}".format(**locals())
                 )
-                unit.Unit.Stop(b"replace")
-                break
-            print("service still runing, sleeping by 5 seconds")
-            time.sleep(5)
+                if unit.Service.MainPID == 0:
+                    print(
+                        "service finished with "
+                        "{unit.Service.ExecMainStatus}/{unit.Service.Result} "
+                        "will stop it and then... bye".format(**locals())
+                    )
+                    unit.Unit.Stop(b"replace")
+                    break
+                print("service still runing, sleeping by 5 seconds")
+                time.sleep(5)

pystemd/__version__.py

@@ -11,7 +11,7 @@
 import sys
 
 
-__version__ = "0.9"
+__version__ = "0.10"
 
 _endstr = ".dev"
 

pystemd/dbusc.pxd

@@ -156,6 +156,9 @@ cdef extern from "systemd/sd-bus.h":
   int sd_bus_path_encode(char* prefix, char* external_id, char **ret_path)
   int sd_bus_path_decode(char* path, char* prefix, char **ret_external_id)
 
+  int sd_bus_set_allow_interactive_authorization(sd_bus *bus, int b);
+  int sd_bus_get_allow_interactive_authorization(sd_bus *bus);
+
 
 
 cdef extern from "systemd/sd-bus-protocol.h":

pystemd/dbuslib.pyi

@@ -42,6 +42,8 @@ class DBus:
     ) -> None: ...
     def wait(self, timeout: int) -> None: ...
     def get_fd(self) -> int: ...
+    def get_allow_interactive_authorization(self) -> bool: ...
+    def set_allow_interactive_authorization(self, interactive: bool) -> None: ...
 
 class DBusMachine(DBus):
     def __init__(self, machine: bytes) -> None: ...

pystemd/dbuslib.pyx

@@ -277,9 +277,11 @@ cdef class DbusMessage:
 cdef class DBus:
     cdef dbusc.sd_bus *bus
     cdef bool user_mode
+    cdef int interactive
 
-    def __init__(self, user_mode=False):
+    def __init__(self, user_mode=False, interactive=None):
       self.user_mode = user_mode
+      self.interactive = -1 if interactive is None else int(interactive)
 
     def __enter__(self):
         self.open()
@@ -301,6 +303,8 @@ cdef class DBus:
         rets = self.open_dbus_bus()
         if (rets < 0):
             raise DBusError(rets, None, "Could not open a bus to DBus")
+        if self.interactive >= 0:
+            self.set_allow_interactive_authorization(self.interactive)
 
     def close(self):
         dbusc.sd_bus_close(self.bus)
@@ -541,6 +545,14 @@ cdef class DBus:
     cpdef int get_fd(self):
       return dbusc.sd_bus_get_fd(self.bus)
 
+    cpdef bool get_allow_interactive_authorization(self):
+      return dbusc.sd_bus_get_allow_interactive_authorization(self.bus)
+
+    cpdef set_allow_interactive_authorization(self, bool interactive):
+        r = dbusc.sd_bus_set_allow_interactive_authorization(self.bus, interactive)
+        if r < 0:
+            raise DBusError(r, None, "Failed to set interactive authorization")
+
 
 cdef class DBusMachine(DBus):
   "DBus class that connects to machine"