ci: improve interop resiliency to loss and corruption

quic/s2n-quic-qns/etc/run_endpoint.sh

@@ -50,6 +50,17 @@ if [ "$QNS_MODE" == "interop" ]; then
         SERVER_PARAMS+=" --application-protocols h3"
         CLIENT_PARAMS+=" --application-protocols h3"
     fi
+
+    if [ "$TESTCASE" == "ecn" ]; then
+      # The ECN test requires all packets set an ECT codepoint to pass. s2n-quic temporarily
+      # stops setting the ECT codepoint after 10 packets in case faulty equipment drops
+      # ECT marked packets (see https://datatracker.ietf.org/doc/html/rfc9000#section-13.4.2)
+      # To increase the chance this test completes in 10 packets or less, we disable
+      # MTU probing to avoid sending MTU probes that contribute to the 10 packet limit.
+      # 1228 is the minimum allowed MaxMtu, see `s2n_quic_core::path::MaxMtu::MIN`
+      SERVER_PARAMS+=" --max-mtu 1228"
+      CLIENT_PARAMS+=" --max-mtu 1228"
+    fi
 fi
 
 if [ "$QNS_MODE" == "interop" ]; then

quic/s2n-quic-qns/src/client/interop.rs

@@ -37,7 +37,7 @@ pub struct Interop {
     #[structopt(long, env = "TESTCASE", possible_values = &Testcase::supported(is_supported_testcase))]
     testcase: Option<Testcase>,
 
-    #[structopt(long, default_value = "10")]
+    #[structopt(long, default_value = "20")]
     concurrency: u64,
 
     #[structopt(min_values = 1, required = true)]

quic/s2n-quic-qns/src/limits.rs

@@ -1,6 +1,8 @@
 // Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 // SPDX-License-Identifier: Apache-2.0
 
+use core::time::Duration;
+
 #[derive(Debug, structopt::StructOpt)]
 pub struct Limits {
     /// The maximum bits/sec for each connection
@@ -16,6 +18,12 @@ pub struct Limits {
 }
 
 impl Limits {
+    // Increase the MaxHandshakeDuration from the default of 10 seconds
+    const MAX_HANDSHAKE_DURATION: Duration = Duration::from_secs(60);
+
+    // Increase MaxIdleTimeout from the default of 30 seconds
+    const MAX_IDLE_TIMEOUT: Duration = Duration::from_secs(60);
+
     pub fn limits(&self) -> s2n_quic::provider::limits::Limits {
         let data_window = self.data_window();
 
@@ -31,6 +39,10 @@ impl Limits {
             .with_bidirectional_remote_data_window(data_window)
             .unwrap()
             .with_unidirectional_data_window(data_window)
+            .unwrap()
+            .with_max_handshake_duration(Self::MAX_HANDSHAKE_DURATION)
+            .unwrap()
+            .with_max_idle_timeout(Self::MAX_IDLE_TIMEOUT)
             .unwrap();
 
         if let Some(size) = self.stream_send_buffer_size {