test(proto): Add and enhance token tests

When we first added tests::util::IncomingConnectionBehavior, we opted to
use an enum instead of a callback because it seemed cleaner. However,
the number of variants have grown, and adding integration tests for
validation tokens from NEW_TOKEN frames threatens to make this logic
even more complicated. Moreover, there is another advantage to callbacks
we have not been exploiting: a stateful FnMut can assert that incoming
connection handling within a test follows a certain expected sequence
of Incoming properties.

As such, this commit replaces TestEndpoint.incoming_connection_behavior
with a handle_incoming callback, modifies some existing tests to exploit
this functionality to test more things than they were previously, and
adds new integration tests for server and client usage of tokens from
NEW_TOKEN frames.

quinn-proto/src/tests/mod.rs

@@ -2,7 +2,7 @@ use std::{
     convert::TryInto,
     mem,
     net::{Ipv4Addr, Ipv6Addr, SocketAddr},
-    sync::Arc,
+    sync::{Arc, Mutex},
 };
 
 use assert_matches::assert_matches;
@@ -186,7 +186,7 @@ fn draft_version_compat() {
 fn stateless_retry() {
     let _guard = subscribe();
     let mut pair = Pair::default();
-    pair.server.incoming_connection_behavior = IncomingConnectionBehavior::Validate;
+    pair.server.handle_incoming = Box::new(validate_incoming);
     let (client_ch, _server_ch) = pair.connect();
     pair.client
         .connections
@@ -200,6 +200,259 @@ fn stateless_retry() {
     assert_eq!(pair.server.known_cids(), 0);
 }
 
+#[test]
+fn use_token() {
+    let _guard = subscribe();
+    let mut pair = Pair::default();
+    let client_config = client_config();
+    let (client_ch, _server_ch) = pair.connect_with(client_config.clone());
+    pair.client
+        .connections
+        .get_mut(&client_ch)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+
+    pair.server.handle_incoming = Box::new(|incoming| {
+        assert!(incoming.remote_address_validated());
+        assert!(incoming.may_retry());
+        IncomingConnectionBehavior::Accept
+    });
+    let (client_ch_2, _server_ch_2) = pair.connect_with(client_config);
+    pair.client
+        .connections
+        .get_mut(&client_ch_2)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+}
+
+#[test]
+fn retry_then_use_token() {
+    let _guard = subscribe();
+    let mut pair = Pair::default();
+    let client_config = client_config();
+    pair.server.handle_incoming = Box::new(validate_incoming);
+    let (client_ch, _server_ch) = pair.connect_with(client_config.clone());
+    pair.client
+        .connections
+        .get_mut(&client_ch)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+
+    pair.server.handle_incoming = Box::new(|incoming| {
+        assert!(incoming.remote_address_validated());
+        assert!(incoming.may_retry());
+        IncomingConnectionBehavior::Accept
+    });
+    let (client_ch_2, _server_ch_2) = pair.connect_with(client_config);
+    pair.client
+        .connections
+        .get_mut(&client_ch_2)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+}
+
+#[test]
+fn use_token_then_retry() {
+    let _guard = subscribe();
+    let mut pair = Pair::default();
+    let client_config = client_config();
+    let (client_ch, _server_ch) = pair.connect_with(client_config.clone());
+    pair.client
+        .connections
+        .get_mut(&client_ch)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+
+    pair.server.handle_incoming = Box::new({
+        let mut i = 0;
+        move |incoming| {
+            if i == 0 {
+                assert!(incoming.remote_address_validated());
+                assert!(incoming.may_retry());
+                i += 1;
+                IncomingConnectionBehavior::Retry
+            } else if i == 1 {
+                assert!(incoming.remote_address_validated());
+                assert!(!incoming.may_retry());
+                i += 1;
+                IncomingConnectionBehavior::Accept
+            } else {
+                panic!("too many handle_incoming iterations")
+            }
+        }
+    });
+    let (client_ch_2, _server_ch_2) = pair.connect_with(client_config);
+    pair.client
+        .connections
+        .get_mut(&client_ch_2)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+}
+
+#[test]
+fn use_same_token_twice() {
+    #[derive(Default)]
+    struct EvilTokenStore(Mutex<Bytes>);
+
+    impl TokenStore for EvilTokenStore {
+        fn insert(&self, _server_name: &str, token: Bytes) {
+            let mut lock = self.0.lock().unwrap();
+            if lock.is_empty() {
+                *lock = token;
+            }
+        }
+
+        fn take(&self, _server_name: &str) -> Option<Bytes> {
+            let lock = self.0.lock().unwrap();
+            if lock.is_empty() {
+                None
+            } else {
+                Some(lock.clone())
+            }
+        }
+    }
+
+    let _guard = subscribe();
+    let mut pair = Pair::default();
+    let mut client_config = client_config();
+    client_config.token_store(Some(Arc::new(EvilTokenStore::default())));
+    let (client_ch, _server_ch) = pair.connect_with(client_config.clone());
+    pair.client
+        .connections
+        .get_mut(&client_ch)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+
+    pair.server.handle_incoming = Box::new(|incoming| {
+        assert!(incoming.remote_address_validated());
+        assert!(incoming.may_retry());
+        IncomingConnectionBehavior::Accept
+    });
+    let (client_ch_2, _server_ch_2) = pair.connect_with(client_config.clone());
+    pair.client
+        .connections
+        .get_mut(&client_ch_2)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+
+    pair.server.handle_incoming = Box::new(|incoming| {
+        assert!(!incoming.remote_address_validated());
+        assert!(incoming.may_retry());
+        IncomingConnectionBehavior::Accept
+    });
+    let (client_ch_3, _server_ch_3) = pair.connect_with(client_config);
+    pair.client
+        .connections
+        .get_mut(&client_ch_3)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+}
+
+#[test]
+fn use_token_expired() {
+    let _guard = subscribe();
+    let mocked_time = Arc::new(MockedTimeSource::new());
+    let lifetime = Duration::from_secs(10000);
+    let mut server_config = server_config();
+    server_config
+        .time_source(Arc::clone(&mocked_time) as _)
+        .validation_token_lifetime(lifetime);
+    let mut pair = Pair::new(Default::default(), server_config);
+    let client_config = client_config();
+    let (client_ch, _server_ch) = pair.connect_with(client_config.clone());
+    pair.client
+        .connections
+        .get_mut(&client_ch)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+
+    pair.server.handle_incoming = Box::new(|incoming| {
+        assert!(incoming.remote_address_validated());
+        assert!(incoming.may_retry());
+        IncomingConnectionBehavior::Accept
+    });
+    let (client_ch_2, _server_ch_2) = pair.connect_with(client_config.clone());
+    pair.client
+        .connections
+        .get_mut(&client_ch_2)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+
+    mocked_time.advance(lifetime + Duration::from_secs(1));
+
+    pair.server.handle_incoming = Box::new(|incoming| {
+        assert!(!incoming.remote_address_validated());
+        assert!(incoming.may_retry());
+        IncomingConnectionBehavior::Accept
+    });
+    let (client_ch_3, _server_ch_3) = pair.connect_with(client_config);
+    pair.client
+        .connections
+        .get_mut(&client_ch_3)
+        .unwrap()
+        .close(pair.time, VarInt(42), Bytes::new());
+    pair.drive();
+    assert_eq!(pair.client.known_connections(), 0);
+    assert_eq!(pair.client.known_cids(), 0);
+    assert_eq!(pair.server.known_connections(), 0);
+    assert_eq!(pair.server.known_cids(), 0);
+}
+
 #[test]
 fn server_stateless_reset() {
     let _guard = subscribe();
@@ -553,7 +806,7 @@ fn high_latency_handshake() {
 fn zero_rtt_happypath() {
     let _guard = subscribe();
     let mut pair = Pair::default();
-    pair.server.incoming_connection_behavior = IncomingConnectionBehavior::Validate;
+    pair.server.handle_incoming = Box::new(validate_incoming);
     let config = client_config();
 
     // Establish normal connection
@@ -722,7 +975,7 @@ fn test_zero_rtt_incoming_limit<F: FnOnce(&mut ServerConfig)>(configure_server:
         CLIENT_PORTS.lock().unwrap().next().unwrap(),
     );
     info!("resuming session");
-    pair.server.incoming_connection_behavior = IncomingConnectionBehavior::Wait;
+    pair.server.handle_incoming = Box::new(|_| IncomingConnectionBehavior::Wait);
     let client_ch = pair.begin_connect(config);
     assert!(pair.client_conn_mut(client_ch).has_0rtt());
     let s = pair.client_streams(client_ch).open(Dir::Uni).unwrap();
@@ -2992,7 +3245,7 @@ fn pure_sender_voluntarily_acks() {
 fn reject_manually() {
     let _guard = subscribe();
     let mut pair = Pair::default();
-    pair.server.incoming_connection_behavior = IncomingConnectionBehavior::RejectAll;
+    pair.server.handle_incoming = Box::new(|_| IncomingConnectionBehavior::Reject);
 
     // The server should now reject incoming connections.
     let client_ch = pair.begin_connect(client_config());
@@ -3012,7 +3265,20 @@ fn reject_manually() {
 fn validate_then_reject_manually() {
     let _guard = subscribe();
     let mut pair = Pair::default();
-    pair.server.incoming_connection_behavior = IncomingConnectionBehavior::ValidateThenReject;
+    pair.server.handle_incoming = Box::new({
+        let mut i = 0;
+        move |incoming| {
+            if incoming.remote_address_validated() {
+                assert_eq!(i, 1);
+                i += 1;
+                IncomingConnectionBehavior::Reject
+            } else {
+                assert_eq!(i, 0);
+                i += 1;
+                IncomingConnectionBehavior::Retry
+            }
+        }
+    });
 
     // The server should now retry and reject incoming connections.
     let client_ch = pair.begin_connect(client_config());