Remove unused test code.

- make naming consistent with the kernel module.
- better distribution of functionality from src/wireguard.rs
- more consistent "import pattern" throughout the project.
- remove unused test code.

1 files changed, 105 insertions, 383 deletions

diff --git a/src/wireguard/wireguard.rs b/src/wireguard/wireguard.rs
index 45b1fcb..2fa14fc 100644
--- a/src/wireguard/wireguard.rs
+++ b/src/wireguard/wireguard.rs
@@ -1,179 +1,122 @@
 use super::constants::*;
 use super::handshake;
+use super::peer::{Peer, PeerInner};
 use super::router;
 use super::timers::{Events, Timers};
-use super::{Peer, PeerInner};
 
 use super::queue::ParallelQueue;
-use super::tun;
-use super::tun::Reader as TunReader;
+use super::workers::HandshakeJob;
 
-use super::udp;
-use super::udp::Reader as UDPReader;
-use super::udp::Writer as UDPWriter;
+use super::tun::Tun;
+use super::udp::UDP;
 
-use super::Endpoint;
-
-use hjul::Runner;
+use super::workers::{handshake_worker, tun_worker, udp_worker};
 
 use std::fmt;
 use std::ops::Deref;
 use std::sync::atomic::{AtomicBool, AtomicU64, AtomicUsize, Ordering};
 use std::sync::Arc;
-use std::thread;
-use std::time::{Duration, Instant};
-
-// TODO: avoid
 use std::sync::Condvar;
 use std::sync::Mutex as StdMutex;
+use std::thread;
+use std::time::Instant;
 
 use std::collections::hash_map::Entry;
 use std::collections::HashMap;
 
-use log::debug;
+use hjul::Runner;
 use rand::rngs::OsRng;
 use rand::Rng;
 use spin::{Mutex, RwLock};
 
-use byteorder::{ByteOrder, LittleEndian};
 use x25519_dalek::{PublicKey, StaticSecret};
 
-const SIZE_HANDSHAKE_QUEUE: usize = 128;
-const THRESHOLD_UNDER_LOAD: usize = SIZE_HANDSHAKE_QUEUE / 4;
-const DURATION_UNDER_LOAD: Duration = Duration::from_millis(10_000);
-
-#[derive(Clone)]
-pub struct WaitHandle(Arc<(StdMutex<usize>, Condvar)>);
-
-impl WaitHandle {
-    pub fn wait(&self) {
-        let (lock, cvar) = &*self.0;
-        let mut nread = lock.lock().unwrap();
-        while *nread > 0 {
-            nread = cvar.wait(nread).unwrap();
-        }
-    }
-
-    fn new() -> Self {
-        Self(Arc::new((StdMutex::new(0), Condvar::new())))
-    }
-
-    fn decrease(&self) {
-        let (lock, cvar) = &*self.0;
-        let mut nread = lock.lock().unwrap();
-        assert!(*nread > 0);
-        *nread -= 1;
-        cvar.notify_all();
-    }
-
-    fn increase(&self) {
-        let (lock, _) = &*self.0;
-        let mut nread = lock.lock().unwrap();
-        *nread += 1;
-    }
-}
-
-pub struct WireguardInner<T: tun::Tun, B: udp::UDP> {
+pub struct WireguardInner<T: Tun, B: UDP> {
     // identifier (for logging)
-    id: u32,
+    pub id: u32,
+
+    // timer wheel
+    pub runner: Mutex<Runner>,
 
     // device enabled
-    enabled: RwLock<bool>,
+    pub enabled: RwLock<bool>,
 
-    // enables waiting for all readers to finish
-    tun_readers: WaitHandle,
+    // number of tun readers
+    pub tun_readers: WaitCounter,
 
     // current MTU
-    mtu: AtomicUsize,
+    pub mtu: AtomicUsize,
 
     // outbound writer
-    send: RwLock<Option<B::Writer>>,
+    pub send: RwLock<Option<B::Writer>>,
 
     // identity and configuration map
-    peers: RwLock<HashMap<[u8; 32], Peer<T, B>>>,
+    pub peers: RwLock<HashMap<[u8; 32], Peer<T, B>>>,
 
     // cryptokey router
-    router: router::Device<B::Endpoint, Events<T, B>, T::Writer, B::Writer>,
+    pub router: router::Device<B::Endpoint, Events<T, B>, T::Writer, B::Writer>,
 
     // handshake related state
-    handshake: RwLock<handshake::Device>,
-    under_load: AtomicBool,
-    pending: AtomicUsize, // num of pending handshake packets in queue
-    queue: ParallelQueue<HandshakeJob<B::Endpoint>>,
+    pub handshake: RwLock<handshake::Device>,
+    pub last_under_load: AtomicUsize,
+    pub pending: AtomicUsize, // num of pending handshake packets in queue
+    pub queue: ParallelQueue<HandshakeJob<B::Endpoint>>,
 }
 
-impl<T: tun::Tun, B: udp::UDP> PeerInner<T, B> {
-    /* Queue a handshake request for the parallel workers
-     * (if one does not already exist)
-     *
-     * The function is ratelimited.
-     */
-    pub fn packet_send_handshake_initiation(&self) {
-        // the function is rate limited
-
-        {
-            let mut lhs = self.last_handshake_sent.lock();
-            if lhs.elapsed() < REKEY_TIMEOUT {
-                return;
-            }
-            *lhs = Instant::now();
-        }
-
-        // create a new handshake job for the peer
-
-        if !self.handshake_queued.swap(true, Ordering::SeqCst) {
-            self.wg.pending.fetch_add(1, Ordering::SeqCst);
-            self.wg.queue.send(HandshakeJob::New(self.pk));
-        }
-    }
+pub struct Wireguard<T: Tun, B: UDP> {
+    inner: Arc<WireguardInner<T, B>>,
 }
 
-pub enum HandshakeJob<E> {
-    Message(Vec<u8>, E),
-    New(PublicKey),
-}
+pub struct WaitCounter(StdMutex<usize>, Condvar);
 
-impl<T: tun::Tun, B: udp::UDP> fmt::Display for WireguardInner<T, B> {
+impl<T: Tun, B: UDP> fmt::Display for Wireguard<T, B> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "wireguard({:x})", self.id)
     }
 }
 
-impl<T: tun::Tun, B: udp::UDP> Deref for Wireguard<T, B> {
-    type Target = Arc<WireguardInner<T, B>>;
+impl<T: Tun, B: UDP> Deref for Wireguard<T, B> {
+    type Target = WireguardInner<T, B>;
     fn deref(&self) -> &Self::Target {
-        &self.state
+        &self.inner
     }
 }
 
-pub struct Wireguard<T: tun::Tun, B: udp::UDP> {
-    runner: Runner,
-    state: Arc<WireguardInner<T, B>>,
+impl<T: Tun, B: UDP> Clone for Wireguard<T, B> {
+    fn clone(&self) -> Self {
+        Wireguard {
+            inner: self.inner.clone(),
+        }
+    }
 }
 
-/* Returns the padded length of a message:
- *
- * # Arguments
- *
- * - `size` : Size of unpadded message
- * - `mtu` : Maximum transmission unit of the device
- *
- * # Returns
- *
- * The padded length (always less than or equal to the MTU)
- */
-#[inline(always)]
-const fn padding(size: usize, mtu: usize) -> usize {
-    #[inline(always)]
-    const fn min(a: usize, b: usize) -> usize {
-        let m = (a < b) as usize;
-        a * m + (1 - m) * b
+impl WaitCounter {
+    pub fn wait(&self) {
+        let mut nread = self.0.lock().unwrap();
+        while *nread > 0 {
+            nread = self.1.wait(nread).unwrap();
+        }
+    }
+
+    fn new() -> Self {
+        Self(StdMutex::new(0), Condvar::new())
+    }
+
+    fn decrease(&self) {
+        let mut nread = self.0.lock().unwrap();
+        assert!(*nread > 0);
+        *nread -= 1;
+        if *nread == 0 {
+            self.1.notify_all();
+        }
+    }
+
+    fn increase(&self) {
+        *self.0.lock().unwrap() += 1;
     }
-    let pad = MESSAGE_PADDING_MULTIPLE;
-    min(mtu, size + (pad - size % pad) % pad)
 }
 
-impl<T: tun::Tun, B: udp::UDP> Wireguard<T, B> {
+impl<T: Tun, B: UDP> Wireguard<T, B> {
     /// Brings the WireGuard device down.
     /// Usually called when the associated interface is brought down.
     ///
@@ -193,7 +136,7 @@ impl<T: tun::Tun, B: udp::UDP> Wireguard<T, B> {
         }
 
         // set mtu
-        self.state.mtu.store(0, Ordering::Relaxed);
+        self.mtu.store(0, Ordering::Relaxed);
 
         // avoid tranmission from router
         self.router.down();
@@ -213,7 +156,7 @@ impl<T: tun::Tun, B: udp::UDP> Wireguard<T, B> {
         let mut enabled = self.enabled.write();
 
         // set mtu
-        self.state.mtu.store(mtu, Ordering::Relaxed);
+        self.mtu.store(mtu, Ordering::Relaxed);
 
         // check if already up
         if *enabled {
@@ -232,25 +175,21 @@ impl<T: tun::Tun, B: udp::UDP> Wireguard<T, B> {
     }
 
     pub fn clear_peers(&self) {
-        self.state.peers.write().clear();
+        self.peers.write().clear();
     }
 
     pub fn remove_peer(&self, pk: &PublicKey) {
         if self.handshake.write().remove(pk).is_ok() {
-            self.state.peers.write().remove(pk.as_bytes());
+            self.peers.write().remove(pk.as_bytes());
         }
     }
 
     pub fn lookup_peer(&self, pk: &PublicKey) -> Option<Peer<T, B>> {
-        self.state
-            .peers
-            .read()
-            .get(pk.as_bytes())
-            .map(|p| p.clone())
+        self.peers.read().get(pk.as_bytes()).map(|p| p.clone())
     }
 
     pub fn list_peers(&self) -> Vec<Peer<T, B>> {
-        let peers = self.state.peers.read();
+        let peers = self.peers.read();
         let mut list = Vec::with_capacity(peers.len());
         for (k, v) in peers.iter() {
             debug_assert!(k == v.pk.as_bytes());
@@ -274,14 +213,14 @@ impl<T: tun::Tun, B: udp::UDP> Wireguard<T, B> {
     }
 
     pub fn set_psk(&self, pk: PublicKey, psk: [u8; 32]) -> bool {
-        self.state.handshake.write().set_psk(pk, psk).is_ok()
+        self.handshake.write().set_psk(pk, psk).is_ok()
     }
     pub fn get_psk(&self, pk: &PublicKey) -> Option<[u8; 32]> {
-        self.state.handshake.read().get_psk(pk).ok()
+        self.handshake.read().get_psk(pk).ok()
     }
 
     pub fn add_peer(&self, pk: PublicKey) -> bool {
-        if self.state.peers.read().contains_key(pk.as_bytes()) {
+        if self.peers.read().contains_key(pk.as_bytes()) {
             return false;
         }
 
@@ -289,28 +228,28 @@ impl<T: tun::Tun, B: udp::UDP> Wireguard<T, B> {
         let state = Arc::new(PeerInner {
             id: rng.gen(),
             pk,
-            wg: self.state.clone(),
+            wg: self.clone(),
             walltime_last_handshake: Mutex::new(None),
             last_handshake_sent: Mutex::new(Instant::now() - TIME_HORIZON),
             handshake_queued: AtomicBool::new(false),
             rx_bytes: AtomicU64::new(0),
             tx_bytes: AtomicU64::new(0),
-            timers: RwLock::new(Timers::dummy(&self.runner)),
+            timers: RwLock::new(Timers::dummy(&*self.runner.lock())),
         });
 
         // create a router peer
-        let router = Arc::new(self.state.router.new_peer(state.clone()));
+        let router = Arc::new(self.router.new_peer(state.clone()));
 
         // form WireGuard peer
         let peer = Peer { router, state };
 
         // finally, add the peer to the wireguard device
-        let mut peers = self.state.peers.write();
+        let mut peers = self.peers.write();
         match peers.entry(*pk.as_bytes()) {
             Entry::Occupied(_) => false,
             Entry::Vacant(vacancy) => {
                 // check that the public key does not cause conflict with the private key of the device
-                let ok_pk = self.state.handshake.write().add(pk).is_ok();
+                let ok_pk = self.handshake.write().add(pk).is_ok();
                 if !ok_pk {
                     return false;
                 }
@@ -324,7 +263,7 @@ impl<T: tun::Tun, B: udp::UDP> Wireguard<T, B> {
                  * This is in fact the only place where the write lock is ever taken.
                  * TODO: Consider the ease of using atomic pointers instead.
                  */
-                *peer.timers.write() = Timers::new(&self.runner, *enabled, peer.clone());
+                *peer.timers.write() = Timers::new(&*self.runner.lock(), *enabled, peer.clone());
 
                 // insert into peer map (takes ownership and ensures that the peer is not dropped)
                 vacancy.insert(peer);
@@ -339,140 +278,33 @@ impl<T: tun::Tun, B: udp::UDP> Wireguard<T, B> {
     /// Any previous reader thread is stopped by closing the previous reader,
     /// which unblocks the thread and causes an error on reader.read
     pub fn add_udp_reader(&self, reader: B::Reader) {
-        let wg = self.state.clone();
+        let wg = self.clone();
         thread::spawn(move || {
-            let mut last_under_load =
-                Instant::now() - DURATION_UNDER_LOAD - Duration::from_millis(1000);
-
-            loop {
-                // create vector big enough for any message given current MTU
-                let mtu = wg.mtu.load(Ordering::Relaxed);
-                let size = mtu + handshake::MAX_HANDSHAKE_MSG_SIZE;
-                let mut msg: Vec<u8> = vec![0; size];
-
-                // read UDP packet into vector
-                let (size, src) = match reader.read(&mut msg) {
-                    Err(e) => {
-                        debug!("Bind reader closed with {}", e);
-                        return;
-                    }
-                    Ok(v) => v,
-                };
-                msg.truncate(size);
-
-                // TODO: start device down
-                if mtu == 0 {
-                    continue;
-                }
-
-                // message type de-multiplexer
-                if msg.len() < std::mem::size_of::<u32>() {
-                    continue;
-                }
-                match LittleEndian::read_u32(&msg[..]) {
-                    handshake::TYPE_COOKIE_REPLY
-                    | handshake::TYPE_INITIATION
-                    | handshake::TYPE_RESPONSE => {
-                        debug!("{} : reader, received handshake message", wg);
-
-                        // add one to pending
-                        let pending = wg.pending.fetch_add(1, Ordering::SeqCst);
-
-                        // update under_load flag
-                        if pending > THRESHOLD_UNDER_LOAD {
-                            debug!("{} : reader, set under load (pending = {})", wg, pending);
-                            last_under_load = Instant::now();
-                            wg.under_load.store(true, Ordering::SeqCst);
-                        } else if last_under_load.elapsed() > DURATION_UNDER_LOAD {
-                            debug!("{} : reader, clear under load", wg);
-                            wg.under_load.store(false, Ordering::SeqCst);
-                        }
-
-                        // add to handshake queue
-                        wg.queue.send(HandshakeJob::Message(msg, src));
-                    }
-                    router::TYPE_TRANSPORT => {
-                        debug!("{} : reader, received transport message", wg);
-
-                        // transport message
-                        let _ = wg.router.recv(src, msg).map_err(|e| {
-                            debug!("Failed to handle incoming transport message: {}", e);
-                        });
-                    }
-                    _ => (),
-                }
-            }
+            udp_worker(&wg, reader);
         });
     }
 
     pub fn set_writer(&self, writer: B::Writer) {
         // TODO: Consider unifying these and avoid Clone requirement on writer
-        *self.state.send.write() = Some(writer.clone());
-        self.state.router.set_outbound_writer(writer);
+        *self.send.write() = Some(writer.clone());
+        self.router.set_outbound_writer(writer);
     }
 
     pub fn add_tun_reader(&self, reader: T::Reader) {
-        fn worker<T: tun::Tun, B: udp::UDP>(wg: &Arc<WireguardInner<T, B>>, reader: T::Reader) {
-            loop {
-                // create vector big enough for any transport message (based on MTU)
-                let mtu = wg.mtu.load(Ordering::Relaxed);
-                let size = mtu + router::SIZE_MESSAGE_PREFIX + 1;
-                let mut msg: Vec<u8> = vec![0; size + router::CAPACITY_MESSAGE_POSTFIX];
-
-                // read a new IP packet
-                let payload = match reader.read(&mut msg[..], router::SIZE_MESSAGE_PREFIX) {
-                    Ok(payload) => payload,
-                    Err(e) => {
-                        debug!("TUN worker, failed to read from tun device: {}", e);
-                        break;
-                    }
-                };
-                debug!("TUN worker, IP packet of {} bytes (MTU = {})", payload, mtu);
-
-                // check if device is down
-                if mtu == 0 {
-                    continue;
-                }
-
-                // truncate padding
-                let padded = padding(payload, mtu);
-                log::trace!(
-                    "TUN worker, payload length = {}, padded length = {}",
-                    payload,
-                    padded
-                );
-                msg.truncate(router::SIZE_MESSAGE_PREFIX + padded);
-                debug_assert!(padded <= mtu);
-                debug_assert_eq!(
-                    if padded < mtu {
-                        (msg.len() - router::SIZE_MESSAGE_PREFIX) % MESSAGE_PADDING_MULTIPLE
-                    } else {
-                        0
-                    },
-                    0
-                );
-
-                // crypt-key route
-                let e = wg.router.send(msg);
-                debug!("TUN worker, router returned {:?}", e);
-            }
-        }
-
-        // start a thread for every reader
-        let wg = self.state.clone();
+        let wg = self.clone();
 
         // increment reader count
         wg.tun_readers.increase();
 
         // start worker
         thread::spawn(move || {
-            worker(&wg, reader);
+            tun_worker(&wg, reader);
             wg.tun_readers.decrease();
         });
     }
 
-    pub fn wait(&self) -> WaitHandle {
-        self.state.tun_readers.clone()
+    pub fn wait(&self) {
+        self.tun_readers.wait();
     }
 
     pub fn new(writer: T::Writer) -> Wireguard<T, B> {
@@ -482,143 +314,33 @@ impl<T: tun::Tun, B: udp::UDP> Wireguard<T, B> {
         // create device state
         let mut rng = OsRng::new().unwrap();
 
-        // handshake queue
+        // create handshake queue
         let (tx, mut rxs) = ParallelQueue::new(cpus, 128);
-        let wg = Arc::new(WireguardInner {
-            enabled: RwLock::new(false),
-            tun_readers: WaitHandle::new(),
-            id: rng.gen(),
-            mtu: AtomicUsize::new(0),
-            peers: RwLock::new(HashMap::new()),
-            send: RwLock::new(None),
-            router: router::Device::new(num_cpus::get(), writer), // router owns the writing half
-            pending: AtomicUsize::new(0),
-            handshake: RwLock::new(handshake::Device::new()),
-            under_load: AtomicBool::new(false),
-            queue: tx,
-        });
+
+        // create arc to state
+        let wg = Wireguard {
+            inner: Arc::new(WireguardInner {
+                enabled: RwLock::new(false),
+                tun_readers: WaitCounter::new(),
+                id: rng.gen(),
+                mtu: AtomicUsize::new(0),
+                peers: RwLock::new(HashMap::new()),
+                last_under_load: AtomicUsize::new(0), // TODO
+                send: RwLock::new(None),
+                router: router::Device::new(num_cpus::get(), writer), // router owns the writing half
+                pending: AtomicUsize::new(0),
+                handshake: RwLock::new(handshake::Device::new()),
+                runner: Mutex::new(Runner::new(TIMERS_TICK, TIMERS_SLOTS, TIMERS_CAPACITY)),
+                queue: tx,
+            }),
+        };
 
         // start handshake workers
         while let Some(rx) = rxs.pop() {
             let wg = wg.clone();
-            thread::spawn(move || {
-                debug!("{} : handshake worker, started", wg);
-
-                // prepare OsRng instance for this thread
-                let mut rng = OsRng::new().expect("Unable to obtain a CSPRNG");
-
-                // process elements from the handshake queue
-                for job in rx {
-                    // decrement pending pakcets (under_load)
-                    let job: HandshakeJob<B::Endpoint> = job;
-                    wg.pending.fetch_sub(1, Ordering::SeqCst);
-
-                    // demultiplex staged handshake jobs and handshake messages
-                    match job {
-                        HandshakeJob::Message(msg, src) => {
-                            // feed message to handshake device
-                            let src_validate = (&src).into_address(); // TODO avoid
-
-                            // process message
-                            let device = wg.handshake.read();
-                            match device.process(
-                                &mut rng,
-                                &msg[..],
-                                if wg.under_load.load(Ordering::Relaxed) {
-                                    debug!("{} : handshake worker, under load", wg);
-                                    Some(&src_validate)
-                                } else {
-                                    None
-                                },
-                            ) {
-                                Ok((pk, resp, keypair)) => {
-                                    // send response (might be cookie reply or handshake response)
-                                    let mut resp_len: u64 = 0;
-                                    if let Some(msg) = resp {
-                                        resp_len = msg.len() as u64;
-                                        let send: &Option<B::Writer> = &*wg.send.read();
-                                        if let Some(writer) = send.as_ref() {
-                                            debug!(
-                                                "{} : handshake worker, send response ({} bytes)",
-                                                wg, resp_len
-                                            );
-                                            let _ = writer.write(&msg[..], &src).map_err(|e| {
-                                                debug!(
-                                                    "{} : handshake worker, failed to send response, error = {}",
-                                                    wg,
-                                                    e
-                                                )
-                                            });
-                                        }
-                                    }
-
-                                    // update peer state
-                                    if let Some(pk) = pk {
-                                        // authenticated handshake packet received
-                                        if let Some(peer) = wg.peers.read().get(pk.as_bytes()) {
-                                            // add to rx_bytes and tx_bytes
-                                            let req_len = msg.len() as u64;
-                                            peer.rx_bytes.fetch_add(req_len, Ordering::Relaxed);
-                                            peer.tx_bytes.fetch_add(resp_len, Ordering::Relaxed);
-
-                                            // update endpoint
-                                            peer.router.set_endpoint(src);
-
-                                            if resp_len > 0 {
-                                                // update timers after sending handshake response
-                                                debug!("{} : handshake worker, handshake response sent", wg);
-                                                peer.state.sent_handshake_response();
-                                            } else {
-                                                // update timers after receiving handshake response
-                                                debug!("{} : handshake worker, handshake response was received", wg);
-                                                peer.state.timers_handshake_complete();
-                                            }
-
-                                            // add any new keypair to peer
-                                            keypair.map(|kp| {
-                                                debug!(
-                                                    "{} : handshake worker, new keypair for {}",
-                                                    wg, peer
-                                                );
-
-                                                // this means that a handshake response was processed or sent
-                                                peer.timers_session_derived();
-
-                                                // free any unused ids
-                                                for id in peer.router.add_keypair(kp) {
-                                                    device.release(id);
-                                                }
-                                            });
-                                        }
-                                    }
-                                }
-                                Err(e) => debug!("{} : handshake worker, error = {:?}", wg, e),
-                            }
-                        }
-                        HandshakeJob::New(pk) => {
-                            if let Some(peer) = wg.peers.read().get(pk.as_bytes()) {
-                                debug!(
-                                    "{} : handshake worker, new handshake requested for {}",
-                                    wg, peer
-                                );
-                                let device = wg.handshake.read();
-                                let _ = device.begin(&mut rng, &peer.pk).map(|msg| {
-                                    let _ = peer.router.send(&msg[..]).map_err(|e| {
-                                        debug!("{} : handshake worker, failed to send handshake initiation, error = {}", wg, e)
-                                    });
-                                    peer.state.sent_handshake_initiation();
-                                });
-                                peer.handshake_queued.store(false, Ordering::SeqCst);
-                            }
-                        }
-                    }
-                }
-            });
+            thread::spawn(move || handshake_worker(&wg, rx));
         }
 
-        Wireguard {
-            state: wg,
-            runner: Runner::new(TIMERS_TICK, TIMERS_SLOTS, TIMERS_CAPACITY),
-        }
+        wg
     }
 }