From a2ebbaa322f4be4fdf068fb471ac0cc867adf6e9 Mon Sep 17 00:00:00 2001
From: grossmj <grossmj@gns3.net>
Date: Sat, 21 May 2016 14:43:10 -0600
Subject: [PATCH] Force Npcap DLL to be used first for Dynamips and uBridge
 (instead of the one from Winpcap if installed).

---
 gns3server/modules/dynamips/hypervisor.py | 10 +++++++++-
 gns3server/ubridge/hypervisor.py          | 10 +++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/gns3server/modules/dynamips/hypervisor.py b/gns3server/modules/dynamips/hypervisor.py
index 18c35352..a94e32df 100644
--- a/gns3server/modules/dynamips/hypervisor.py
+++ b/gns3server/modules/dynamips/hypervisor.py
@@ -19,6 +19,7 @@
 Represents a Dynamips hypervisor and starts/stops the associated Dynamips process.
 """
 
+import sys
 import os
 import subprocess
 import asyncio
@@ -117,6 +118,12 @@ class Hypervisor(DynamipsHypervisor):
         """
 
         self._command = self._build_command()
+        env = os.environ.copy()
+        if sys.platform.startswith("win"):
+            # add the Npcap directory to $PATH to force Dynamips to use npcap DLL instead of Winpcap (if installed)
+            system_root = os.path.join(os.path.expandvars("%SystemRoot%"), "System32", "Npcap")
+            if os.path.isdir(system_root):
+                env["PATH"] = system_root + ';' + env["PATH"]
         try:
             log.info("Starting Dynamips: {}".format(self._command))
             self._stdout_file = os.path.join(self.working_dir, "dynamips_i{}_stdout.txt".format(self._id))
@@ -125,7 +132,8 @@ class Hypervisor(DynamipsHypervisor):
                 self._process = yield from asyncio.create_subprocess_exec(*self._command,
                                                                           stdout=fd,
                                                                           stderr=subprocess.STDOUT,
-                                                                          cwd=self._working_dir)
+                                                                          cwd=self._working_dir,
+                                                                          env=env)
             log.info("Dynamips process started PID={}".format(self._process.pid))
             self._started = True
         except (OSError, subprocess.SubprocessError) as e:
diff --git a/gns3server/ubridge/hypervisor.py b/gns3server/ubridge/hypervisor.py
index 929d06f6..7c43e838 100644
--- a/gns3server/ubridge/hypervisor.py
+++ b/gns3server/ubridge/hypervisor.py
@@ -19,6 +19,7 @@
 Represents a uBridge hypervisor and starts/stops the associated uBridge process.
 """
 
+import sys
 import os
 import subprocess
 import asyncio
@@ -140,6 +141,12 @@ class Hypervisor(UBridgeHypervisor):
         """
 
         yield from self._check_ubridge_version()
+        env = os.environ.copy()
+        if sys.platform.startswith("win"):
+            # add the Npcap directory to $PATH to force Dynamips to use npcap DLL instead of Winpcap (if installed)
+            system_root = os.path.join(os.path.expandvars("%SystemRoot%"), "System32", "Npcap")
+            if os.path.isdir(system_root):
+                env["PATH"] = system_root + ';' + env["PATH"]
         try:
             command = self._build_command()
             log.info("starting ubridge: {}".format(command))
@@ -149,7 +156,8 @@ class Hypervisor(UBridgeHypervisor):
                 self._process = yield from asyncio.create_subprocess_exec(*command,
                                                                           stdout=fd,
                                                                           stderr=subprocess.STDOUT,
-                                                                          cwd=self._working_dir)
+                                                                          cwd=self._working_dir,
+                                                                          env=env)
 
             log.info("ubridge started PID={}".format(self._process.pid))
         except (OSError, subprocess.SubprocessError) as e: