.devcontainer/Dockerfile

@@ -1,6 +0,0 @@
-# See here for image contents: https://github.com/microsoft/vscode-dev-containers/tree/v0.148.1/containers/rust/.devcontainer/base.Dockerfile
-
-FROM mcr.microsoft.com/vscode/devcontainers/rust:0-1
-
-RUN apt-get update && export DEBIAN_FRONTEND=noninteractive \
-     && apt-get -y install --no-install-recommends asciidoctor

.devcontainer/devcontainer.json

@@ -1,35 +0,0 @@
-{
-	"name": "Rust",
-	"build": {
-		"dockerfile": "Dockerfile"
-	},
-	"runArgs": [ "--cap-add=SYS_PTRACE", "--security-opt", "seccomp=unconfined" ],
-
-	// Set *default* container specific settings.json values on container create.
-	"settings": { 
-		"terminal.integrated.shell.linux": "/bin/bash",
-		"lldb.executable": "/usr/bin/lldb",
-		// VS Code don't watch files under ./target
-		"files.watcherExclude": {
-			"**/target/**": true
-		}
-	},
-
-	// Add the IDs of extensions you want installed when the container is created.
-	"extensions": [
-		"rust-lang.rust",
-		"bungcip.better-toml",
-		"vadimcn.vscode-lldb",
-		"mutantdino.resourcemonitor",
-		"asciidoctor.asciidoctor-vscode"
-	],
-
-	// Use 'forwardPorts' to make a list of ports inside the container available locally.
-	// "forwardPorts": [],
-
-	// Use 'postCreateCommand' to run commands after the container is created.
-	// "postCreateCommand": "rustc --version",
-
-	// Comment out connect as root instead. More info: https://aka.ms/vscode-remote/containers/non-root.
-	"remoteUser": "vscode"
-}

CHANGELOG.md

@@ -2,10 +2,6 @@
 
 This project follows [semantic versioning](http://semver.org).
 
-### UNRELEASED
-
-- [removed] Removed dummy device type
-
 ### v2.0.1 (2020-11-07)
 
 - [changed] Changed documentation

src/cloud.rs

@@ -106,7 +106,7 @@ impl<D: Device, P: Protocol, S: Socket, TS: TimeSource> GenericCloud<D, P, S, TS
             Mode::Normal => {
                 match config.device_type {
                     Type::Tap => (true, true),
-                    Type::Tun => (false, false)
+                    Type::Tun | Type::Dummy => (false, false)
                 }
             }
             Mode::Router => (false, false),

src/config.rs

@@ -589,7 +589,7 @@ statsd:
 #[test]
 fn default_config_as_default() {
     let mut default_config = Config {
-        device_type: Type::Tun,
+        device_type: Type::Dummy,
         device_name: "".to_string(),
         device_path: None,
         fix_rp_filter: false,

src/device.rs

@@ -51,14 +51,18 @@ pub enum Type {
     Tun,
     /// Tap interface: This interface transports Ethernet frames.
     #[serde(rename = "tap")]
-    Tap
+    Tap,
+    /// Dummy interface: This interface does nothing.
+    #[serde(rename = "dummy")]
+    Dummy
 }
 
 impl fmt::Display for Type {
     fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
         match *self {
             Type::Tun => write!(formatter, "tun"),
-            Type::Tap => write!(formatter, "tap")
+            Type::Tap => write!(formatter, "tap"),
+            Type::Dummy => write!(formatter, "dummy")
         }
     }
 }
@@ -70,6 +74,7 @@ impl FromStr for Type {
         Ok(match &text.to_lowercase() as &str {
             "tun" => Self::Tun,
             "tap" => Self::Tap,
+            "dummy" => Self::Dummy,
             _ => return Err("Unknown device type")
         })
     }
@@ -139,10 +144,14 @@ impl TunTapDevice {
     #[allow(clippy::useless_conversion)]
     pub fn new(ifname: &str, type_: Type, path: Option<&str>) -> io::Result<Self> {
         let path = path.unwrap_or_else(|| Self::default_path(type_));
+        if type_ == Type::Dummy {
+            return Self::dummy(ifname, path, type_)
+        }
         let fd = fs::OpenOptions::new().read(true).write(true).open(path)?;
         let flags = match type_ {
             Type::Tun => libc::IFF_TUN | libc::IFF_NO_PI,
-            Type::Tap => libc::IFF_TAP | libc::IFF_NO_PI
+            Type::Tap => libc::IFF_TAP | libc::IFF_NO_PI,
+            Type::Dummy => unreachable!()
         };
         let mut ifreq = IfReq::new(ifname);
         ifreq.data.flags = flags as libc::c_short;
@@ -163,10 +172,33 @@ impl TunTapDevice {
     #[inline]
     pub fn default_path(type_: Type) -> &'static str {
         match type_ {
-            Type::Tun | Type::Tap => "/dev/net/tun"
+            Type::Tun | Type::Tap => "/dev/net/tun",
+            Type::Dummy => "/dev/null"
         }
     }
 
+    /// Creates a dummy device based on an existing file
+    ///
+    /// This method opens a regular or special file and reads from it to receive packets and
+    /// writes to it to send packets. This method does not use a networking device and therefore
+    /// can be used for testing.
+    ///
+    /// The parameter `path` is the file that should be used. Special files like `/dev/null`,
+    /// named pipes and unix sockets can be used with this method.
+    ///
+    /// Both `ifname` and `type_` parameters have no effect.
+    ///
+    /// # Errors
+    /// This method will return an error if the file can not be opened for reading and writing.
+    #[allow(dead_code)]
+    pub fn dummy(ifname: &str, path: &str, type_: Type) -> io::Result<Self> {
+        Ok(TunTapDevice {
+            fd: fs::OpenOptions::new().create(true).read(true).write(true).open(path)?,
+            ifname: ifname.to_string(),
+            type_
+        })
+    }
+
     #[cfg(any(target_os = "linux", target_os = "android"))]
     #[inline]
     fn correct_data_after_read(&mut self, _buffer: &mut MsgBuffer) {}
@@ -223,7 +255,7 @@ impl TunTapDevice {
         + 1 /* message type header */
         + match self.type_ {
             Type::Tap => 14, /* inner ethernet header */
-            Type::Tun => 0
+            Type::Tun | Type::Dummy => 0
         }
     }
 
@@ -325,7 +357,7 @@ impl MockDevice {
 
 impl Device for MockDevice {
     fn get_type(&self) -> Type {
-        Type::Tun
+        Type::Dummy
     }
 
     fn ifname(&self) -> &str {

src/main.rs

@@ -286,6 +286,7 @@ fn main() {
     debug!("Config: {:?}", config);
     match config.device_type {
         Type::Tap => run::<payload::Frame>(config),
-        Type::Tun => run::<payload::Packet>(config)
+        Type::Tun => run::<payload::Packet>(config),
+        Type::Dummy => run::<payload::Frame>(config)
     }
 }

src/poll/epoll.rs

@@ -6,7 +6,7 @@ use crate::device::Device;
 use std::{io, os::unix::io::RawFd};
 
 use super::WaitResult;
-use crate::net::Socket;
+use crate::{device::Type, net::Socket};
 
 pub struct EpollWait {
     poll_fd: RawFd,
@@ -31,10 +31,15 @@ impl EpollWait {
         if poll_fd == -1 {
             return Err(io::Error::last_os_error())
         }
-        for fd in &[socket.as_raw_fd(), device.as_raw_fd()] {
+        let raw_fds = if device.get_type() != Type::Dummy {
-            event.u64 = *fd as u64;
+            vec![socket.as_raw_fd(), device.as_raw_fd()]
+        } else {
+            vec![socket.as_raw_fd()]
+        };
+        for fd in raw_fds {
+            event.u64 = fd as u64;
             event.events = flags;
-            let res = unsafe { libc::epoll_ctl(poll_fd, libc::EPOLL_CTL_ADD, *fd, &mut event) };
+            let res = unsafe { libc::epoll_ctl(poll_fd, libc::EPOLL_CTL_ADD, fd, &mut event) };
             if res == -1 {
                 return Err(io::Error::last_os_error())
             }