UDP connection checks.

gns3server/modules/dynamips/__init__.py

@@ -25,6 +25,7 @@ import base64
 import tempfile
 import shutil
 import glob
+import socket
 from gns3server.modules import IModule
 import gns3server.jsonrpc as jsonrpc
 
@@ -363,6 +364,12 @@ class Dynamips(IModule):
             lport = request["nio"]["lport"]
             rhost = request["nio"]["rhost"]
             rport = request["nio"]["rport"]
+            try:
+                #TODO: handle IPv6
+                with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as sock:
+                    sock.connect((rhost, rport))
+            except OSError as e:
+                raise DynamipsError("Could not create an UDP connection to {}:{}: {}".format(rhost, rport, e))
             # check if we have an allocated NIO UDP auto
             nio = node.hypervisor.get_nio_udp_auto(lport)
             if not nio:

gns3server/modules/iou/__init__.py

@@ -658,6 +658,12 @@ class IOU(IModule):
                 lport = request["nio"]["lport"]
                 rhost = request["nio"]["rhost"]
                 rport = request["nio"]["rport"]
+                try:
+                    #TODO: handle IPv6
+                    with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as sock:
+                        sock.connect((rhost, rport))
+                except OSError as e:
+                    raise IOUError("Could not create an UDP connection to {}:{}: {}".format(rhost, rport, e))
                 nio = NIO_UDP(lport, rhost, rport)
             elif request["nio"]["type"] == "nio_tap":
                 tap_device = request["nio"]["tap_device"]

gns3server/modules/vpcs/__init__.py

@@ -625,6 +625,12 @@ class VPCS(IModule):
                 lport = request["nio"]["lport"]
                 rhost = request["nio"]["rhost"]
                 rport = request["nio"]["rport"]
+                try:
+                    #TODO: handle IPv6
+                    with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as sock:
+                        sock.connect((rhost, rport))
+                except OSError as e:
+                    raise VPCSError("Could not create an UDP connection to {}:{}: {}".format(rhost, rport, e))
                 nio = NIO_UDP(lport, rhost, rport)
             elif request["nio"]["type"] == "nio_tap":
                 tap_device = request["nio"]["tap_device"]