make installer pull in tuntap driver

cmake/installer.cmake

@@ -7,5 +7,9 @@ set(CPACK_PACKAGE_VERSION_PATCH "${LLARP_VERSION_PATCH}")
 set(CPACK_RESOURCE_FILE_LICENSE "${CMAKE_SOURCE_DIR}/LICENSE")
 set(CPACK_PACKAGE_INSTALL_DIRECTORY "lokinet")
 
+if(WIN32)
+  include(cmake/win32_installer_deps.cmake)
+endif()
+
 # This must always be last!
 include(CPack)

cmake/win32_installer_deps.cmake

@@ -0,0 +1,9 @@
+set(TUNTAP_URL "https://build.openvpn.net/downloads/releases/latest/tap-windows-latest-stable.exe")
+set(TUNTAP_EXE "${CMAKE_BINARY_DIR}/tuntap-install.exe")
+file(DOWNLOAD
+    ${TUNTAP_URL}
+    ${TUNTAP_EXE})
+install(PROGRAMS ${TUNTAP_EXE} DESTINATION bin)
+set(CPACK_NSIS_DEFINES "RequestExecutionLevel admin")
+set(CPACK_NSIS_EXTRA_INSTALL_COMMANDS "ExecWait '$INSTDIR\\\\bin\\\\tuntap-install.exe /S'")
+set(CPACK_NSIS_EXTRA_UNINSTALL_COMMANDS "ExecWait 'C:\\\\Program Files\\\\TAP-Windows\\\\Uninstall.exe /S'")