[trac800] Actually starting the creator

src/bin/bind10/bind10_messages.mes

@@ -189,3 +189,12 @@ the given file number.
 Either sending or receiving data from the socket creator failed with the given
 error. The creator probably crashed or some serious OS-level problem happened,
 as the communication happens only on local host.
+
+% BIND10_SOCKCREATOR_CRASHED the socket creator crashed
+The socket creator terminated unexpectadly. It is not possible to restart it
+(because the boss already gave up root privileges), so the system is going
+to terminate.
+
+% BIND10_SOCKCREATOR_KILL killing the socket creator
+The socket creator is being terminated the aggressive way, by sending it
+sigkill. This should not happen usually.

src/bin/bind10/bind10_src.py.in

@@ -67,6 +67,7 @@ import isc.util.process
 import isc.net.parse
 import isc.log
 from bind10_messages import *
+import bind10.sockcreator
 
 isc.log.init("b10-boss")
 logger = isc.log.Logger("boss")
@@ -248,6 +249,7 @@ class BoB:
         self.config_filename = config_filename
         self.cmdctl_port = cmdctl_port
         self.brittle = brittle
+        self.sockcreator = None
 
     def config_handler(self, new_config):
         # If this is initial update, don't do anything now, leave it to startup
@@ -333,6 +335,20 @@ class BoB:
                                                             "Unknown command")
         return answer
 
+    def start_creator(self):
+        self.curproc = 'b10-sockcreator'
+        self.sockcreator = bind10.sockcreator.Creator("@@LIBEXECDIR@@:" +
+                                                      os.environ['PATH'])
+
+    def stop_creator(self, kill=False):
+        if self.sockcreator is None:
+            return
+        if kill:
+            self.sockcreator.kill()
+        else:
+            self.sockcreator.terminate()
+        self.sockcreator = None
+
     def kill_started_processes(self):
         """
             Called as part of the exception handling when a process fails to
@@ -341,6 +357,8 @@ class BoB:
         """
         logger.info(BIND10_KILLING_ALL_PROCESSES)
 
+        self.stop_creator(True)
+
         for pid in self.processes:
             logger.info(BIND10_KILL_PROCESS, self.processes[pid].name)
             self.processes[pid].process.kill()
@@ -571,6 +589,11 @@ class BoB:
             Starts up all the processes.  Any exception generated during the
             starting of the processes is handled by the caller.
         """
+        # The socket creator first, as it is the only thing that needs root
+        self.start_creator()
+        # TODO: Once everything uses the socket creator, we can drop root
+        # privileges right now
+
         c_channel_env = self.c_channel_env
         self.start_msgq(c_channel_env)
         self.start_cfgmgr(c_channel_env)
@@ -660,6 +683,8 @@ class BoB:
         self.cc_session.group_sendmsg(cmd, "Zonemgr", "Zonemgr")
         self.cc_session.group_sendmsg(cmd, "Stats", "Stats")
         self.cc_session.group_sendmsg(cmd, "StatsHttpd", "StatsHttpd")
+        # Terminate the creator last
+        self.stop_creator()
 
     def stop_process(self, process, recipient):
         """
@@ -746,7 +771,14 @@ class BoB:
                 # XXX: should be impossible to get any other error here
                 raise
             if pid == 0: break
-            if pid in self.processes:
+            if self.sockcreator is not None and self.sockcreator.pid() == pid:
+                # This is the socket creator, started and terminated
+                # differently. This can't be restarted.
+                if self.runnable:
+                    logger.fatal(BIND10_SOCKCREATOR_CRASHED)
+                    self.sockcreator = None
+                    self.runnable = False
+            elif pid in self.processes:
                 # One of the processes we know about.  Get information on it.
                 proc_info = self.processes.pop(pid)
                 proc_info.restart_schedule.set_run_stop_time()

src/bin/bind10/sockcreator.py

@@ -16,6 +16,7 @@
 import socket
 import struct
 import os
+import subprocess
 from bind10_messages import *
 from libutil_io_python import recv_fd
 
@@ -191,3 +192,33 @@ class WrappedSocket:
         Read the file descriptor from the socket.
         """
         return recv_fd(self.fileno())
+
+# FIXME: Any idea how to test this? Starting an external process doesn't sound
+# OK
+class Creator(Parser):
+    """
+    This starts the socket creator and allows asking for the sockets.
+    """
+    def __init__(self, path):
+        (local, remote) = socket.socketpair(socket.AF_UNIX, socket.SOCK_STREAM)
+        # Popen does not like, for some reason, having the same socket for
+        # stdin as well as stdout, so we dup it before passing it there.
+        remote2 = socket.fromfd(remote.fileno(), socket.AF_UNIX,
+                                socket.SOCK_STREAM)
+        env = os.environ
+        env['PATH'] = path
+        self.__process = subprocess.Popen(['b10-sockcreator'], env=env,
+                                          stdin=remote.fileno(),
+                                          stdout=remote2.fileno())
+        remote.close()
+        remote2.close()
+        Parser.__init__(self, WrappedSocket(local))
+
+    def pid(self):
+        return self.__process.pid
+
+    def kill(self):
+        logger.warn(BIND10_SOCKCREATOR_KILL)
+        if self.__process is not None:
+            self.__process.kill()
+            self.__process = None

src/bin/bind10/tests/bind10_test.py.in

@@ -193,6 +193,13 @@ class MockBob(BoB):
         self.cmdctl = False
         self.c_channel_env = {}
         self.processes = { }
+        self.creator = False
+
+    def start_creator(self):
+        self.creator = True
+
+    def stop_creator(self, kill=False):
+        self.creator = False
 
     def read_bind10_config(self):
         # Configuration options are set directly
@@ -337,6 +344,7 @@ class TestStartStopProcessesBob(unittest.TestCase):
         self.assertEqual(bob.msgq, core)
         self.assertEqual(bob.cfgmgr, core)
         self.assertEqual(bob.ccsession, core)
+        self.assertEqual(bob.creator, core)
         self.assertEqual(bob.auth, auth)
         self.assertEqual(bob.resolver, resolver)
         self.assertEqual(bob.xfrout, auth)