Implements uBridge hypervisor.

gns3server/handlers/api/vmware_handler.py

@@ -267,7 +267,7 @@ class VMwareHandler:
         if nio_type != "nio_udp":
             raise HTTPConflict(text="NIO of type {} is not supported".format(nio_type))
         nio = vmware_manager.create_nio(None, request.json)
-        vm.adapter_add_nio_binding(int(request.match_info["adapter_number"]), nio)
+        yield from vm.adapter_add_nio_binding(int(request.match_info["adapter_number"]), nio)
         response.set_status(201)
         response.json(nio)
 
@@ -290,5 +290,5 @@ class VMwareHandler:
 
         vmware_manager = VMware.instance()
         vm = vmware_manager.get_vm(request.match_info["vm_id"], project_id=request.match_info["project_id"])
-        vm.adapter_remove_nio_binding(int(request.match_info["adapter_number"]))
+        yield from vm.adapter_remove_nio_binding(int(request.match_info["adapter_number"]))
         response.set_status(204)

gns3server/modules/dynamips/hypervisor.py

@@ -24,6 +24,7 @@ import subprocess
 import tempfile
 import asyncio
 
+from gns3server.utils.asyncio import wait_for_process_termination
 from .dynamips_hypervisor import DynamipsHypervisor
 from .dynamips_error import DynamipsError
 
@@ -146,7 +147,7 @@ class Hypervisor(DynamipsHypervisor):
             # time to delete UNIX NIOs for instance.
             yield from asyncio.sleep(0.01)
             try:
-                yield from asyncio.wait_for(self._process.wait(), timeout=3)
+                yield from wait_for_process_termination(self._process, timeout=3)
             except asyncio.TimeoutError:
                 if self._process.returncode is None:
                     log.warn("Dynamips process {} is still running... killing it".format(self._process.pid))

gns3server/modules/vmware/vmware_vm.py

@@ -22,15 +22,12 @@ VMware VM instance.
 import sys
 import os
 import socket
-import subprocess
-import configparser
 import shutil
 import asyncio
 import tempfile
-import signal
 
-from gns3server.utils.asyncio import wait_for_process_termination
+from pkg_resources import parse_version
-from gns3server.utils.asyncio import monitor_process
+from gns3server.ubridge.hypervisor import Hypervisor
 from gns3server.utils.telnet_server import TelnetServer
 from gns3server.utils.interfaces import get_windows_interfaces
 from collections import OrderedDict
@@ -59,8 +56,7 @@ class VMwareVM(BaseVM):
 
         self._linked_clone = linked_clone
         self._vmx_pairs = OrderedDict()
-        self._ubridge_process = None
+        self._ubridge_hypervisor = None
-        self._ubridge_stdout_file = ""
         self._telnet_server_thread = None
         self._serial_pipe = None
         self._vmnets = []
@@ -259,27 +255,23 @@ class VMwareVM(BaseVM):
                 log.debug("disabling remaining adapter {}".format(adapter_number))
                 self._vmx_pairs["ethernet{}.startconnected".format(adapter_number)] = "FALSE"
 
-        self._update_ubridge_config()
+    @asyncio.coroutine
-
+    def _add_ubridge_connection(self, nio, adapter_number):
-    def _update_ubridge_config(self):
-        """
-        Updates the ubrige.ini file.
         """
+        Creates a connection in uBridge.
 
-        ubridge_ini = os.path.join(self.working_dir, "ubridge.ini")
+        :param nio: NIO instance
-        config = configparser.ConfigParser()
+        :param adapter_number: adapter number
-        for adapter_number in range(0, self._adapters):
+        """
-            nio = self._ethernet_adapters[adapter_number].get_nio(0)
-            if nio:
-                bridge_name = "bridge{}".format(adapter_number)
 
         vnet = "ethernet{}.vnet".format(adapter_number)
         if vnet not in self._vmx_pairs:
-                    continue
+            raise VMwareError("vnet {} not in VMX file".format(vnet))
-
+        yield from self._ubridge_hypervisor.send("bridge create {name}".format(name=vnet))
         vmnet_interface = os.path.basename(self._vmx_pairs[vnet])
         if sys.platform.startswith("linux"):
-                    config[bridge_name] = {"source_linux_raw": vmnet_interface}
+            yield from self._ubridge_hypervisor.send('bridge add_nio_linux_raw {name} "{interface}"'.format(name=vnet,
+                                                                                                            interface=vmnet_interface))
         elif sys.platform.startswith("win"):
             windows_interfaces = get_windows_interfaces()
             npf = None
@@ -289,29 +281,38 @@ class VMwareVM(BaseVM):
                 elif vmnet_interface in interface["name"]:
                     npf = interface["id"]
             if npf:
-                        config[bridge_name] = {"source_ethernet": '"' + npf + '"'}
+                yield from self._ubridge_hypervisor.send('bridge add_nio_ethernet {name} "{interface}"'.format(name=vnet,
+                                                                                                               interface=npf))
             else:
                 raise VMwareError("Could not find NPF id for VMnet interface {}".format(vmnet_interface))
         else:
-                    config[bridge_name] = {"source_ethernet": vmnet_interface}
+            yield from self._ubridge_hypervisor.send('bridge add_nio_ethernet {name} "{interface}"'.format(name=vnet,
+                                                                                                           interface=vmnet_interface))
 
         if isinstance(nio, NIOUDP):
-                    udp_tunnel_info = {"destination_udp": "{lport}:{rhost}:{rport}".format(lport=nio.lport,
+            yield from self._ubridge_hypervisor.send('bridge add_nio_udp {name} {lport} {rhost} {rport}'.format(name=vnet,
+                                                                                                                lport=nio.lport,
                                                                                                                 rhost=nio.rhost,
-                                                                                           rport=nio.rport)}
+                                                                                                                rport=nio.rport))
-                    config[bridge_name].update(udp_tunnel_info)
 
         if nio.capturing:
-                    capture_info = {"pcap_file": "{pcap_file}".format(pcap_file=nio.pcap_output_file)}
+            yield from self._ubridge_hypervisor.send('bridge start_capture {name} "{pcap_file}"'.format(name=vnet,
-                    config[bridge_name].update(capture_info)
+                                                                                                        pcap_file=nio.pcap_output_file))
 
-        try:
+        yield from self._ubridge_hypervisor.send('bridge start {name}'.format(name=vnet))
-            with open(ubridge_ini, "w", encoding="utf-8") as config_file:
+
-                config.write(config_file)
+    @asyncio.coroutine
-            log.info('VMware VM "{name}" [id={id}]: ubridge.ini updated'.format(name=self._name,
+    def _delete_ubridge_connection(self, adapter_number):
-                                                                                id=self._id))
+        """
-        except OSError as e:
+        Deletes a connection in uBridge.
-            raise VMwareError("Could not create {}: {}".format(ubridge_ini, e))
+
+        :param adapter_number: adapter number
+        """
+
+        vnet = "ethernet{}.vnet".format(adapter_number)
+        if vnet not in self._vmx_pairs:
+            raise VMwareError("vnet {} not in VMX file".format(vnet))
+        yield from self._ubridge_hypervisor.send("bridge delete {name}".format(name=vnet))
 
     @property
     def ubridge_path(self):
@@ -332,74 +333,16 @@ class VMwareVM(BaseVM):
         Starts uBridge (handles connections to and from this VMware VM).
         """
 
-        try:
+        server_config = self._manager.config.get_section_config("Server")
-            # self._update_ubridge_config()
+        server_host = server_config.get("host")
-            command = [self.ubridge_path]
+        self._ubridge_hypervisor = Hypervisor(self._project, self.ubridge_path, self.working_dir, server_host)
-            log.info("starting ubridge: {}".format(command))
-            self._ubridge_stdout_file = os.path.join(self.working_dir, "ubridge.log")
-            log.info("logging to {}".format(self._ubridge_stdout_file))
-            with open(self._ubridge_stdout_file, "w", encoding="utf-8") as fd:
-                self._ubridge_process = yield from asyncio.create_subprocess_exec(*command,
-                                                                                  stdout=fd,
-                                                                                  stderr=subprocess.STDOUT,
-                                                                                  cwd=self.working_dir)
 
-                #monitor_process(self._ubridge_process, self._termination_callback)
+        log.info("Starting new uBridge hypervisor {}:{}".format(self._ubridge_hypervisor.host, self._ubridge_hypervisor.port))
-            log.info("ubridge started PID={}".format(self._ubridge_process.pid))
+        yield from self._ubridge_hypervisor.start()
-        except (OSError, subprocess.SubprocessError) as e:
+        log.info("Hypervisor {}:{} has successfully started".format(self._ubridge_hypervisor.host, self._ubridge_hypervisor.port))
-            ubridge_stdout = self.read_ubridge_stdout()
+        yield from self._ubridge_hypervisor.connect()
-            log.error("Could not start ubridge: {}\n{}".format(e, ubridge_stdout))
+        if parse_version(self._ubridge_hypervisor.version) < parse_version('0.9.1'):
-            raise VMwareError("Could not start ubridge: {}\n{}".format(e, ubridge_stdout))
+            raise VMwareError("uBridge version must be >= 0.9.1, detected version is {}".format(self._ubridge_hypervisor.version))
-
-    def _termination_callback(self, returncode):
-        """
-        Called when the process has stopped.
-
-        :param returncode: Process returncode
-        """
-
-        log.info("uBridge process has stopped, return code: %d", returncode)
-        if returncode != 0:
-            self.project.emit("log.error", {"message": "uBridge process has stopped, return code: {}\n{}".format(returncode, self.read_ubridge_stdout())})
-
-    def is_ubridge_running(self):
-        """
-        Checks if the ubridge process is running
-
-        :returns: True or False
-        """
-
-        if self._ubridge_process and self._ubridge_process.returncode is None:
-            return True
-        return False
-
-    def read_ubridge_stdout(self):
-        """
-        Reads the standard output of the uBridge process.
-        Only use when the process has been stopped or has crashed.
-        """
-
-        output = ""
-        if self._ubridge_stdout_file:
-            try:
-                with open(self._ubridge_stdout_file, "rb") as file:
-                    output = file.read().decode("utf-8", errors="replace")
-            except OSError as e:
-                log.warn("could not read {}: {}".format(self._ubridge_stdout_file, e))
-        return output
-
-    def _terminate_process_ubridge(self):
-        """
-        Terminate the ubridge process if running.
-        """
-
-        if self._ubridge_process:
-            log.info('Stopping uBridge process for VMware VM "{}" PID={}'.format(self.name, self._ubridge_process.pid))
-            try:
-                self._ubridge_process.terminate()
-            # Sometime the process can already be dead when we garbage collect
-            except ProcessLookupError:
-                pass
 
     @asyncio.coroutine
     def start(self):
@@ -427,12 +370,17 @@ class VMwareVM(BaseVM):
         except OSError as e:
             raise VMwareError('Could not write VMware VMX file "{}": {}'.format(self._vmx_path, e))
 
-        yield from self._start_ubridge()
         if self._headless:
             yield from self._control_vm("start", "nogui")
         else:
             yield from self._control_vm("start")
 
+        yield from self._start_ubridge()
+        for adapter_number in range(0, self._adapters):
+            nio = self._ethernet_adapters[adapter_number].get_nio(0)
+            if nio:
+                yield from self._add_ubridge_connection(nio, adapter_number)
+
         if self._enable_remote_console and self._console is not None:
             yield from asyncio.sleep(1)  # give some time to VMware to create the pipe file.
             self._start_remote_console()
@@ -447,15 +395,8 @@ class VMwareVM(BaseVM):
         """
 
         self._stop_remote_console()
-        if self.is_ubridge_running():
+        if self._ubridge_hypervisor and self._ubridge_hypervisor.is_running():
-            self._terminate_process_ubridge()
+            yield from self._ubridge_hypervisor.stop()
-            try:
-                yield from wait_for_process_termination(self._ubridge_process, timeout=3)
-            except asyncio.TimeoutError:
-                if self._ubridge_process.returncode is None:
-                    log.warn("uBridge process {} is still running... killing it".format(self._ubridge_process.pid))
-                    self._ubridge_process.kill()
-            self._ubridge_process = None
 
         try:
             if self.acpi_shutdown:
@@ -697,7 +638,7 @@ class VMwareVM(BaseVM):
         :param adapters: number of adapters
         """
 
-        # VMware VMs are limit to 10 adapters
+        # VMware VMs are limited to 10 adapters
         if adapters > 10:
             raise VMwareError("Number of adapters above the maximum supported of 10")
 
@@ -757,20 +698,7 @@ class VMwareVM(BaseVM):
             log.info("VMware VM '{name}' [{id}] is not allowed to use any adapter".format(name=self.name, id=self.id))
         self._use_any_adapter = use_any_adapter
 
-    def _reload_ubridge(self):
+    @asyncio.coroutine
-        """
-        Reloads ubridge.
-        """
-
-        if self.is_ubridge_running():
-            self._update_ubridge_config()
-            if not sys.platform.startswith("win"):
-                os.kill(self._ubridge_process.pid, signal.SIGHUP)
-            else:
-                # Windows doesn't support SIGHUP...
-                self._terminate_process_ubridge()
-                self._start_ubridge()
-
     def adapter_add_nio_binding(self, adapter_number, nio):
         """
         Adds an adapter NIO binding.
@@ -786,13 +714,16 @@ class VMwareVM(BaseVM):
                                                                                                     adapter_number=adapter_number))
 
         adapter.add_nio(0, nio)
+        if self._started:
+            yield from self._add_ubridge_connection(nio, adapter_number)
+
         log.info("VMware VM '{name}' [{id}]: {nio} added to adapter {adapter_number}".format(name=self.name,
                                                                                              id=self.id,
                                                                                              nio=nio,
                                                                                              adapter_number=adapter_number))
 
-        self._reload_ubridge()
 
+    @asyncio.coroutine
     def adapter_remove_nio_binding(self, adapter_number):
         """
         Removes an adapter NIO binding.
@@ -812,13 +743,14 @@ class VMwareVM(BaseVM):
         if isinstance(nio, NIOUDP):
             self.manager.port_manager.release_udp_port(nio.lport, self._project)
         adapter.remove_nio(0)
+        if self._started:
+            yield from self._delete_ubridge_connection(adapter_number)
 
         log.info("VMware VM '{name}' [{id}]: {nio} removed from adapter {adapter_number}".format(name=self.name,
                                                                                                  id=self.id,
                                                                                                  nio=nio,
                                                                                                  adapter_number=adapter_number))
 
-        self._reload_ubridge()
         return nio
 
     def _get_pipe_name(self):

gns3server/ubridge/hypervisor.py

@@ -0,0 +1,210 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2015 GNS3 Technologies Inc.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""
+Represents a uBridge hypervisor and starts/stops the associated uBridge process.
+"""
+
+import os
+import subprocess
+import asyncio
+import socket
+
+from gns3server.utils.asyncio import wait_for_process_termination
+from gns3server.utils.asyncio import monitor_process
+from .ubridge_hypervisor import UBridgeHypervisor
+from .ubridge_error import UbridgeError
+
+import logging
+log = logging.getLogger(__name__)
+
+
+class Hypervisor(UBridgeHypervisor):
+
+    """
+    Hypervisor.
+
+    :param project: Project instance
+    :param path: path to uBridge executable
+    :param working_dir: working directory
+    :param host: host/address for this hypervisor
+    :param port: port for this hypervisor
+    """
+
+    _instance_count = 1
+
+    def __init__(self, project, path, working_dir, host, port=None):
+
+        if port is None:
+            try:
+                port = None
+                info = socket.getaddrinfo(host, 0, socket.AF_UNSPEC, socket.SOCK_STREAM, 0, socket.AI_PASSIVE)
+                if not info:
+                    raise UbridgeError("getaddrinfo returns an empty list on {}".format(host))
+                for res in info:
+                    af, socktype, proto, _, sa = res
+                    # let the OS find an unused port for the uBridge hypervisor
+                    with socket.socket(af, socktype, proto) as sock:
+                        sock.bind(sa)
+                        port = sock.getsockname()[1]
+                        break
+            except OSError as e:
+                raise UbridgeError("Could not find free port for the uBridge hypervisor: {}".format(e))
+
+        super().__init__(host, port)
+        self._project = project
+        self._path = path
+        self._working_dir = working_dir
+        self._command = []
+        self._process = None
+        self._stdout_file = ""
+        self._started = False
+
+    @property
+    def process(self):
+        """
+        Returns the subprocess of the Hypervisor
+
+        :returns: subprocess
+        """
+
+        return self._process
+
+    @property
+    def started(self):
+        """
+        Returns either this hypervisor has been started or not.
+
+        :returns: boolean
+        """
+
+        return self._started
+
+    @property
+    def path(self):
+        """
+        Returns the path to the uBridge executable.
+
+        :returns: path to uBridge
+        """
+
+        return self._path
+
+    @path.setter
+    def path(self, path):
+        """
+        Sets the path to the uBridge executable.
+
+        :param path: path to uBridge
+        """
+
+        self._path = path
+
+    @asyncio.coroutine
+    def start(self):
+        """
+        Starts the uBridge hypervisor process.
+        """
+
+        try:
+            # self._update_ubridge_config()
+            command = self._build_command()
+            log.info("starting ubridge: {}".format(command))
+            self._stdout_file = os.path.join(self._working_dir, "ubridge.log")
+            log.info("logging to {}".format(self._stdout_file))
+            with open(self._stdout_file, "w", encoding="utf-8") as fd:
+                self._process = yield from asyncio.create_subprocess_exec(*command,
+                                                                          stdout=fd,
+                                                                          stderr=subprocess.STDOUT,
+                                                                          cwd=self._working_dir)
+
+                monitor_process(self._process, self._termination_callback)
+            log.info("ubridge started PID={}".format(self._process.pid))
+        except (OSError, subprocess.SubprocessError) as e:
+            ubridge_stdout = self.read_stdout()
+            log.error("Could not start ubridge: {}\n{}".format(e, ubridge_stdout))
+            raise UBridgeHypervisor("Could not start ubridge: {}\n{}".format(e, ubridge_stdout))
+
+    def _termination_callback(self, returncode):
+        """
+        Called when the process has stopped.
+
+        :param returncode: Process returncode
+        """
+
+        log.info("uBridge process has stopped, return code: %d", returncode)
+        if returncode != 0:
+            self._project.emit("log.error", {"message": "uBridge process has stopped, return code: {}\n{}".format(returncode, self.read_stdout())})
+
+    @asyncio.coroutine
+    def stop(self):
+        """
+        Stops the uBridge hypervisor process.
+        """
+
+        if self.is_running():
+            log.info("Stopping uBridge process PID={}".format(self._process.pid))
+            yield from UBridgeHypervisor.stop(self)
+            try:
+                yield from wait_for_process_termination(self._process, timeout=3)
+            except asyncio.TimeoutError:
+                if self._process.returncode is None:
+                    log.warn("uBridge process {} is still running... killing it".format(self._process.pid))
+                    self._process.kill()
+
+        if self._stdout_file and os.access(self._stdout_file, os.W_OK):
+            try:
+                os.remove(self._stdout_file)
+            except OSError as e:
+                log.warning("could not delete temporary uBridge log file: {}".format(e))
+        self._started = False
+
+    def read_stdout(self):
+        """
+        Reads the standard output of the uBridge process.
+        Only use when the process has been stopped or has crashed.
+        """
+
+        output = ""
+        if self._stdout_file and os.access(self._stdout_file, os.R_OK):
+            try:
+                with open(self._stdout_file, "rb") as file:
+                    output = file.read().decode("utf-8", errors="replace")
+            except OSError as e:
+                log.warn("could not read {}: {}".format(self._stdout_file, e))
+        return output
+
+    def is_running(self):
+        """
+        Checks if the process is running
+
+        :returns: True or False
+        """
+
+        if self._process and self._process.returncode is None:
+            return True
+        return False
+
+    def _build_command(self):
+        """
+        Command to start the uBridge hypervisor process.
+        (to be passed to subprocess.Popen())
+        """
+
+        command = [self._path]
+        command.extend(["-H", "{}:{}".format(self._host, self._port)])
+        return command

gns3server/ubridge/ubridge_error.py

@@ -0,0 +1,26 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2015 GNS3 Technologies Inc.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""
+Custom exceptions for the ubridge.
+"""
+
+
+class UbridgeError(Exception):
+
+    def __init__(self, message):
+        Exception.__init__(self, message)

gns3server/ubridge/ubridge_hypervisor.py

@@ -0,0 +1,264 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2015 GNS3 Technologies Inc.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import re
+import time
+import logging
+import asyncio
+
+from .ubridge_error import UbridgeError
+
+log = logging.getLogger(__name__)
+
+
+class UBridgeHypervisor:
+
+    """
+    Creates a new connection to uBridge hypervisor.
+
+    :param host: the hostname or ip address string of the uBridge hypervisor
+    :param port: the tcp port integer
+    :param timeout: timeout integer for how long to wait for a response to commands sent to the
+    hypervisor (defaults to 30 seconds)
+    """
+
+    # Used to parse Ubridge response codes
+    error_re = re.compile(r"""^2[0-9]{2}-""")
+    success_re = re.compile(r"""^1[0-9]{2}\s{1}""")
+
+    def __init__(self, host, port, timeout=30.0):
+
+        self._host = host
+        self._port = port
+        self._version = "N/A"
+        self._timeout = timeout
+        self._reader = None
+        self._writer = None
+        self._io_lock = asyncio.Lock()
+
+    @asyncio.coroutine
+    def connect(self, timeout=10):
+        """
+        Connects to the hypervisor.
+        """
+
+        # connect to a local address by default
+        # if listening to all addresses (IPv4 or IPv6)
+        if self._host == "0.0.0.0":
+            host = "127.0.0.1"
+        elif self._host == "::":
+            host = "::1"
+        else:
+            host = self._host
+
+        begin = time.time()
+        connection_success = False
+        last_exception = None
+        while time.time() - begin < timeout:
+            yield from asyncio.sleep(0.01)
+            try:
+                self._reader, self._writer = yield from asyncio.open_connection(host, self._port)
+            except OSError as e:
+                last_exception = e
+                continue
+            connection_success = True
+            break
+
+        if not connection_success:
+            raise UbridgeError("Couldn't connect to hypervisor on {}:{} :{}".format(host, self._port, last_exception))
+        else:
+            log.info("Connected to uBridge hypervisor after {:.4f} seconds".format(time.time() - begin))
+
+        try:
+            version = yield from self.send("hypervisor version")
+            self._version = version[0].split("-", 1)[0]
+        except IndexError:
+            self._version = "Unknown"
+
+    @property
+    def version(self):
+        """
+        Returns uBridge version.
+
+        :returns: version string
+        """
+
+        return self._version
+
+    @asyncio.coroutine
+    def close(self):
+        """
+        Closes the connection to this hypervisor (but leave it running).
+        """
+
+        yield from self.send("hypervisor close")
+        self._writer.close()
+        self._reader, self._writer = None
+
+    @asyncio.coroutine
+    def stop(self):
+        """
+        Stops this hypervisor (will no longer run).
+        """
+
+        try:
+            # try to properly stop the hypervisor
+            yield from self.send("hypervisor stop")
+        except UbridgeError:
+            pass
+        try:
+            if self._writer is not None:
+                yield from self._writer.drain()
+                self._writer.close()
+        except OSError as e:
+            log.debug("Stopping hypervisor {}:{} {}".format(self._host, self._port, e))
+        self._reader = self._writer = None
+
+    @asyncio.coroutine
+    def reset(self):
+        """
+        Resets this hypervisor (used to get an empty configuration).
+        """
+
+        yield from self.send("hypervisor reset")
+
+    @property
+    def port(self):
+        """
+        Returns the port used to start the hypervisor.
+
+        :returns: port number (integer)
+        """
+
+        return self._port
+
+    @port.setter
+    def port(self, port):
+        """
+        Sets the port used to start the hypervisor.
+
+        :param port: port number (integer)
+        """
+
+        self._port = port
+
+    @property
+    def host(self):
+        """
+        Returns the host (binding) used to start the hypervisor.
+
+        :returns: host/address (string)
+        """
+
+        return self._host
+
+    @host.setter
+    def host(self, host):
+        """
+        Sets the host (binding) used to start the hypervisor.
+
+        :param host: host/address (string)
+        """
+
+        self._host = host
+
+    @asyncio.coroutine
+    def send(self, command):
+        """
+        Sends commands to this hypervisor.
+
+        :param command: a uBridge hypervisor command
+
+        :returns: results as a list
+        """
+
+        # uBridge responses are of the form:
+        #   1xx yyyyyy\r\n
+        #   1xx yyyyyy\r\n
+        #   ...
+        #   100-yyyy\r\n
+        # or
+        #   2xx-yyyy\r\n
+        #
+        # Where 1xx is a code from 100-199 for a success or 200-299 for an error
+        # The result might be multiple lines and might be less than the buffer size
+        # but still have more data. The only thing we know for sure is the last line
+        # will begin with '100-' or a '2xx-' and end with '\r\n'
+
+        with (yield from self._io_lock):
+            if self._writer is None or self._reader is None:
+                raise UbridgeError("Not connected")
+
+            try:
+                command = command.strip() + '\n'
+                log.debug("sending {}".format(command))
+                self._writer.write(command.encode())
+                yield from self._writer.drain()
+            except OSError as e:
+                raise UbridgeError("Lost communication with {host}:{port} :{error}, Dynamips process running: {run}"
+                                   .format(host=self._host, port=self._port, error=e, run=self.is_running()))
+
+            # Now retrieve the result
+            data = []
+            buf = ''
+            while True:
+                try:
+                    try:
+                        chunk = yield from self._reader.read(1024)
+                    except asyncio.CancelledError:
+                        # task has been canceled but continue to read
+                        # any remaining data sent by the hypervisor
+                        continue
+                    if not chunk:
+                        raise UbridgeError("No data returned from {host}:{port}, uBridge process running: {run}"
+                                           .format(host=self._host, port=self._port, run=self.is_running()))
+                    buf += chunk.decode("utf-8")
+                except OSError as e:
+                    raise UbridgeError("Lost communication with {host}:{port} :{error}, uBridge process running: {run}"
+                                       .format(host=self._host, port=self._port, error=e, run=self.is_running()))
+
+                # If the buffer doesn't end in '\n' then we can't be done
+                try:
+                    if buf[-1] != '\n':
+                        continue
+                except IndexError:
+                    raise UbridgeError("Could not communicate with {host}:{port}, uBridge process running: {run}"
+                                       .format(host=self._host, port=self._port, run=self.is_running()))
+
+                data += buf.split('\r\n')
+                if data[-1] == '':
+                    data.pop()
+                buf = ''
+
+                # Does it contain an error code?
+                if self.error_re.search(data[-1]):
+                    raise UbridgeError(data[-1][4:])
+
+                # Or does the last line begin with '100-'? Then we are done!
+                if data[-1][:4] == '100-':
+                    data[-1] = data[-1][4:]
+                    if data[-1] == 'OK':
+                        data.pop()
+                    break
+
+            # Remove success responses codes
+            for index in range(len(data)):
+                if self.success_re.search(data[index]):
+                    data[index] = data[index][4:]
+
+            log.debug("returned result {}".format(data))
+            return data