Move to nested handshake message structure

Having the nested structure:

    Handshake Message:
        Noise part (zerocopy message)
        MAC footer part (zerocopy message)

Greatly simplifies processing the MAC fields,
since the MAC footer covers the noise part, which can
be accessed as bytes using AsBytes.

1 files changed, 0 insertions, 315 deletions

diff --git a/src/noise/device.rs b/src/noise/device.rs
deleted file mode 100644
index 04e00f9..0000000
--- a/src/noise/device.rs
+++ /dev/null
@@ -1,315 +0,0 @@
-use spin::RwLock;
-use std::collections::HashMap;
-
-use rand::prelude::*;
-use rand::rngs::OsRng;
-
-use x25519_dalek::PublicKey;
-use x25519_dalek::StaticSecret;
-
-use super::messages;
-use super::noise;
-use super::peer::Peer;
-use super::types::*;
-
-pub struct Device<T> {
-    pub sk: StaticSecret,                   // static secret key
-    pub pk: PublicKey,                      // static public key
-    pk_map: HashMap<[u8; 32], Peer<T>>,     // public key  -> peer state
-    id_map: RwLock<HashMap<u32, [u8; 32]>>, // receiver ids -> public key
-}
-
-/* A mutable reference to the device needs to be held during configuration.
- * Wrapping the device in a RwLock enables peer config after "configuration time"
- */
-impl<T> Device<T>
-where
-    T: Copy,
-{
-    /// Initialize a new handshake state machine
-    ///
-    /// # Arguments
-    ///
-    /// * `sk` - x25519 scalar representing the local private key
-    pub fn new(sk: StaticSecret) -> Device<T> {
-        Device {
-            pk: PublicKey::from(&sk),
-            sk: sk,
-            pk_map: HashMap::new(),
-            id_map: RwLock::new(HashMap::new()),
-        }
-    }
-
-    /// Add a new public key to the state machine
-    /// To remove public keys, you must create a new machine instance
-    ///
-    /// # Arguments
-    ///
-    /// * `pk` - The public key to add
-    /// * `identifier` - Associated identifier which can be used to distinguish the peers
-    pub fn add(&mut self, pk: PublicKey, identifier: T) -> Result<(), ConfigError> {
-        // check that the pk is not added twice
-
-        if let Some(_) = self.pk_map.get(pk.as_bytes()) {
-            return Err(ConfigError::new("Duplicate public key"));
-        };
-
-        // check that the pk is not that of the device
-
-        if *self.pk.as_bytes() == *pk.as_bytes() {
-            return Err(ConfigError::new(
-                "Public key corresponds to secret key of interface",
-            ));
-        }
-
-        // map : pk -> new index
-
-        self.pk_map.insert(
-            *pk.as_bytes(),
-            Peer::new(identifier, pk, self.sk.diffie_hellman(&pk)),
-        );
-
-        Ok(())
-    }
-
-    /// Remove a peer by public key
-    /// To remove public keys, you must create a new machine instance
-    ///
-    /// # Arguments
-    ///
-    /// * `pk` - The public key of the peer to remove
-    ///
-    /// # Returns
-    ///
-    /// The call might fail if the public key is not found
-    pub fn remove(&mut self, pk: PublicKey) -> Result<(), ConfigError> {
-        // take write-lock on receive id table
-        let mut id_map = self.id_map.write();
-
-        // remove the peer
-        self.pk_map
-            .remove(pk.as_bytes())
-            .ok_or(ConfigError::new("Public key not in device"))?;
-
-        // pruge the id map (linear scan)
-        id_map.retain(|_, v| v != pk.as_bytes());
-        Ok(())
-    }
-
-    /// Add a psk to the peer
-    ///
-    /// # Arguments
-    ///
-    /// * `pk` - The public key of the peer
-    /// * `psk` - The psk to set / unset
-    ///
-    /// # Returns
-    ///
-    /// The call might fail if the public key is not found
-    pub fn set_psk(&mut self, pk: PublicKey, psk: Option<Psk>) -> Result<(), ConfigError> {
-        match self.pk_map.get_mut(pk.as_bytes()) {
-            Some(mut peer) => {
-                peer.psk = match psk {
-                    Some(v) => v,
-                    None => [0u8; 32],
-                };
-                Ok(())
-            }
-            _ => Err(ConfigError::new("No such public key")),
-        }
-    }
-
-    /// Return the psk for the peer
-    ///
-    /// # Arguments
-    ///
-    /// * `pk` - The public key of the peer
-    ///
-    /// # Returns
-    ///
-    /// A 32 byte array holding the PSK
-    ///
-    /// The call might fail if the public key is not found
-    pub fn get_psk(&self, pk: PublicKey) -> Result<Psk, ConfigError> {
-        match self.pk_map.get(pk.as_bytes()) {
-            Some(peer) => Ok(peer.psk),
-            _ => Err(ConfigError::new("No such public key")),
-        }
-    }
-
-    /// Release an id back to the pool
-    ///
-    /// # Arguments
-    ///
-    /// * `id` - The (sender) id to release
-    pub fn release(&self, id: u32) {
-        let mut m = self.id_map.write();
-        debug_assert!(m.contains_key(&id), "Releasing id not allocated");
-        m.remove(&id);
-    }
-
-    /// Begin a new handshake
-    ///
-    /// # Arguments
-    ///
-    /// * `pk` - Public key of peer to initiate handshake for
-    pub fn begin(&self, pk: &PublicKey) -> Result<Vec<u8>, HandshakeError> {
-        match self.pk_map.get(pk.as_bytes()) {
-            None => Err(HandshakeError::UnknownPublicKey),
-            Some(peer) => {
-                let sender = self.allocate(peer);
-                noise::create_initiation(self, peer, sender)
-            }
-        }
-    }
-
-    /// Process a handshake message.
-    ///
-    /// # Arguments
-    ///
-    /// * `msg` - Byte slice containing the message (untrusted input)
-    pub fn process(&self, msg: &[u8]) -> Result<Output<T>, HandshakeError> {
-        match msg.get(0) {
-            Some(&messages::TYPE_INITIATION) => {
-                // consume the initiation
-                let (peer, st) = noise::consume_initiation(self, msg)?;
-
-                // allocate new index for response
-                let sender = self.allocate(peer);
-
-                // create response (release id on error)
-                noise::create_response(peer, sender, st).map_err(|e| {
-                    self.release(sender);
-                    e
-                })
-            }
-            Some(&messages::TYPE_RESPONSE) => noise::consume_response(self, msg),
-            _ => Err(HandshakeError::InvalidMessageFormat),
-        }
-    }
-
-    // Internal function
-    //
-    // Return the peer associated with the public key
-    pub(crate) fn lookup_pk(&self, pk: &PublicKey) -> Result<&Peer<T>, HandshakeError> {
-        self.pk_map
-            .get(pk.as_bytes())
-            .ok_or(HandshakeError::UnknownPublicKey)
-    }
-
-    // Internal function
-    //
-    // Return the peer currently associated with the receiver identifier
-    pub(crate) fn lookup_id(&self, id: u32) -> Result<&Peer<T>, HandshakeError> {
-        let im = self.id_map.read();
-        let pk = im.get(&id).ok_or(HandshakeError::UnknownReceiverId)?;
-        match self.pk_map.get(pk) {
-            Some(peer) => Ok(peer),
-            _ => unreachable!(), // if the id-lookup succeeded, the peer should exist
-        }
-    }
-
-    // Internal function
-    //
-    // Allocated a new receiver identifier for the peer
-    fn allocate(&self, peer: &Peer<T>) -> u32 {
-        let mut rng = OsRng::new().unwrap();
-
-        loop {
-            let id = rng.gen();
-
-            // check membership with read lock
-            if self.id_map.read().contains_key(&id) {
-                continue;
-            }
-
-            // take write lock and add index
-            let mut m = self.id_map.write();
-            if !m.contains_key(&id) {
-                m.insert(id, *peer.pk.as_bytes());
-                return id;
-            }
-        }
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use hex;
-    use messages::*;
-
-    #[test]
-    fn handshake() {
-        // generate new keypairs
-
-        let mut rng = OsRng::new().unwrap();
-
-        let sk1 = StaticSecret::new(&mut rng);
-        let pk1 = PublicKey::from(&sk1);
-
-        let sk2 = StaticSecret::new(&mut rng);
-        let pk2 = PublicKey::from(&sk2);
-
-        // pick random psk
-
-        let mut psk = [0u8; 32];
-        rng.fill_bytes(&mut psk[..]);
-
-        // intialize devices on both ends
-
-        let mut dev1 = Device::new(sk1);
-        let mut dev2 = Device::new(sk2);
-
-        dev1.add(pk2, 1337).unwrap();
-        dev2.add(pk1, 2600).unwrap();
-
-        dev1.set_psk(pk2, Some(psk)).unwrap();
-        dev2.set_psk(pk1, Some(psk)).unwrap();
-
-        // do a few handshakes
-
-        for i in 0..10 {
-            println!("handshake : {}", i);
-
-            // create initiation
-
-            let msg1 = dev1.begin(&pk2).unwrap();
-
-            println!("msg1 = {}", hex::encode(&msg1[..]));
-            println!("msg1 = {:?}", Initiation::parse(&msg1[..]).unwrap());
-
-            // process initiation and create response
-
-            let (_, msg2, ks_r) = dev2.process(&msg1).unwrap();
-
-            let ks_r = ks_r.unwrap();
-            let msg2 = msg2.unwrap();
-
-            println!("msg2 = {}", hex::encode(&msg2[..]));
-            println!("msg2 = {:?}", Response::parse(&msg2[..]).unwrap());
-
-            assert!(!ks_r.confirmed, "Responders key-pair is confirmed");
-
-            // process response and obtain confirmed key-pair
-
-            let (_, msg3, ks_i) = dev1.process(&msg2).unwrap();
-            let ks_i = ks_i.unwrap();
-
-            assert!(msg3.is_none(), "Returned message after response");
-            assert!(ks_i.confirmed, "Initiators key-pair is not confirmed");
-
-            assert_eq!(ks_i.send, ks_r.recv, "KeyI.send != KeyR.recv");
-            assert_eq!(ks_i.recv, ks_r.send, "KeyI.recv != KeyR.send");
-
-            dev1.release(ks_i.send.id);
-            dev2.release(ks_r.send.id);
-        }
-
-        assert_eq!(dev1.get_psk(pk2).unwrap(), psk);
-        assert_eq!(dev2.get_psk(pk1).unwrap(), psk);
-
-        dev1.remove(pk2).unwrap();
-        dev2.remove(pk1).unwrap();
-    }
-}