From 7ac527309d47c5cf6e9843ffe68c435a899e8111 Mon Sep 17 00:00:00 2001
From: Thomas Eizinger <thomas@eizinger.io>
Date: Mon, 16 Oct 2023 13:15:25 +1100
Subject: [PATCH] Make `Tunn::set_static_private` infallible

---
 boringtun/src/device/mod.rs      | 27 +++++----------------------
 boringtun/src/noise/handshake.rs |  5 ++---
 boringtun/src/noise/mod.rs       |  8 +++-----
 3 files changed, 10 insertions(+), 30 deletions(-)

diff --git a/boringtun/src/device/mod.rs b/boringtun/src/device/mod.rs
index 8cd1c7c8..04cd7285 100644
--- a/boringtun/src/device/mod.rs
+++ b/boringtun/src/device/mod.rs
@@ -452,8 +452,6 @@ impl Device {
     }
 
     fn set_key(&mut self, private_key: x25519::StaticSecret) {
-        let mut bad_peers = vec![];
-
         let public_key = x25519::PublicKey::from(&private_key);
         let key_pair = Some((private_key.clone(), public_key));
 
@@ -466,30 +464,15 @@ impl Device {
         let rate_limiter = Arc::new(RateLimiter::new(&public_key, HANDSHAKE_RATE_LIMIT));
 
         for peer in self.peers.values_mut() {
-            let mut peer_mut = peer.lock();
-
-            if peer_mut
-                .tunnel
-                .set_static_private(
-                    private_key.clone(),
-                    public_key,
-                    Some(Arc::clone(&rate_limiter)),
-                )
-                .is_err()
-            {
-                // In case we encounter an error, we will remove that peer
-                // An error will be a result of bad public key/secret key combination
-                bad_peers.push(Arc::clone(peer));
-            }
+            peer.lock().tunnel.set_static_private(
+                private_key.clone(),
+                public_key,
+                Some(Arc::clone(&rate_limiter)),
+            )
         }
 
         self.key_pair = key_pair;
         self.rate_limiter = Some(rate_limiter);
-
-        // Remove all the bad peers
-        for _ in bad_peers {
-            unimplemented!();
-        }
     }
 
     #[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
diff --git a/boringtun/src/noise/handshake.rs b/boringtun/src/noise/handshake.rs
index 2ee6711f..40ed8037 100644
--- a/boringtun/src/noise/handshake.rs
+++ b/boringtun/src/noise/handshake.rs
@@ -395,7 +395,7 @@ impl NoiseParams {
         &mut self,
         static_private: x25519::StaticSecret,
         static_public: x25519::PublicKey,
-    ) -> Result<(), WireGuardError> {
+    ) {
         // Check that the public key indeed matches the private key
         let check_key = x25519::PublicKey::from(&static_private);
         assert_eq!(check_key.as_bytes(), static_public.as_bytes());
@@ -404,7 +404,6 @@ impl NoiseParams {
         self.static_public = static_public;
 
         self.static_shared = self.static_private.diffie_hellman(&self.peer_static_public);
-        Ok(())
     }
 }
 
@@ -475,7 +474,7 @@ impl Handshake {
         &mut self,
         private_key: x25519::StaticSecret,
         public_key: x25519::PublicKey,
-    ) -> Result<(), WireGuardError> {
+    ) {
         self.params.set_static_private(private_key, public_key)
     }
 
diff --git a/boringtun/src/noise/mod.rs b/boringtun/src/noise/mod.rs
index 62cec983..76e377b6 100644
--- a/boringtun/src/noise/mod.rs
+++ b/boringtun/src/noise/mod.rs
@@ -229,17 +229,16 @@ impl Tunn {
         static_private: x25519::StaticSecret,
         static_public: x25519::PublicKey,
         rate_limiter: Option<Arc<RateLimiter>>,
-    ) -> Result<(), WireGuardError> {
+    ) {
         self.timers.should_reset_rr = rate_limiter.is_none();
         self.rate_limiter = rate_limiter.unwrap_or_else(|| {
             Arc::new(RateLimiter::new(&static_public, PEER_HANDSHAKE_RATE_LIMIT))
         });
         self.handshake
-            .set_static_private(static_private, static_public)?;
+            .set_static_private(static_private, static_public);
         for s in &mut self.sessions {
             *s = None;
         }
-        Ok(())
     }
 
     /// Encapsulate a single packet from the tunnel interface.
@@ -605,8 +604,7 @@ mod tests {
 
         let my_tun = Tunn::new(my_secret_key, their_public_key, None, None, my_idx, None);
 
-        let their_tun =
-            Tunn::new(their_secret_key, my_public_key, None, None, their_idx, None);
+        let their_tun = Tunn::new(their_secret_key, my_public_key, None, None, their_idx, None);
 
         (my_tun, their_tun)
     }