disable nginx session tickets for resumption test

With Nginx 1.24.0 we saw a regression in the runner `nginx` test when
checking that session resumption worked as expected with a `curl`
client. This commit fixes the issue by disabling `ssl_session_tickets`
for the server config using `ssl_session_cache shared:...` (port 8446).

Since Nginx 1.23.2, the `shared` session cache has done double duty,
also managing generating, storing, and updating TLS session ticket keys.
This is done primarily with the OpenSSL
`SSL_CTX_set_tlsext_ticket_key_cb`/`SSL_CTX_set_tlsext_ticket_key_evp_cb`
APIs, which we don't yet support. We're also not setting a ticketer for
the Rustls `ServerConfig` we construct.

The net result is that when using our compat shim with Nginx 1.23.2+ we
need to explicitly disable session ticket support in order for the
`shared` session cache to work the way we expect for classic sessions.

rustls-libssl/tests/nginx.conf

@@ -102,6 +102,11 @@ http {
         # per-server resumption
         listen 8446 ssl;
         ssl_session_cache shared:port8446:1M;
+        # We don't presently support session tickets and on nginx 1.23.2+ the "shared"
+        # ssl_session_cache is also used to generate, store, and rotate TLS session
+        # ticket keys. With this enabled, the 'shared' cache will not function.
+        # TODO(XXX): revisit with ticket support, https://github.com/rustls/rustls-openssl-compat/issues/30
+        ssl_session_tickets off;
         ssl_certificate ../../../test-ca/rsa/server.cert;
         ssl_certificate_key ../../../test-ca/rsa/server.key;
         server_name localhost;

rustls-libssl/tests/runner.rs

@@ -502,42 +502,37 @@ fn nginx() {
         b"hello world\n"
     );
 
-    // TODO(XXX): Session resumption is not working w/ nginx 1.24.0+
-    //   Until this is fixed skip the resumption specific tests with
-    //   newer Nginx versions.
-    if matches!(nginx_version(), (1, minor) if minor < 24) {
-        for (port, reused) in [(8443, '.'), (8444, 'r'), (8445, 'r'), (8446, 'r')] {
-            // multiple requests without http connection reuse
-            // (second should be a TLS resumption if possible)
-            assert_eq!(
-                Command::new("curl")
-                    .env("LD_LIBRARY_PATH", "")
-                    .args([
-                        "--verbose",
-                        "--cacert",
-                        "test-ca/rsa/ca.cert",
-                        "-H",
-                        "connection: close",
-                        &format!("https://localhost:{port}/"),
-                        &format!("https://localhost:{port}/ssl-agreed"),
-                        &format!("https://localhost:{port}/ssl-server-name"),
-                        &format!("https://localhost:{port}/ssl-was-reused")
-                    ])
-                    .stdout(Stdio::piped())
-                    .output()
-                    .map(print_output)
-                    .unwrap()
-                    .stdout,
-                format!(
-                    "hello world\n\
+    for (port, reused) in [(8443, '.'), (8444, 'r'), (8445, 'r'), (8446, 'r')] {
+        // multiple requests without http connection reuse
+        // (second should be a TLS resumption if possible)
+        assert_eq!(
+            Command::new("curl")
+                .env("LD_LIBRARY_PATH", "")
+                .args([
+                    "--verbose",
+                    "--cacert",
+                    "test-ca/rsa/ca.cert",
+                    "-H",
+                    "connection: close",
+                    &format!("https://localhost:{port}/"),
+                    &format!("https://localhost:{port}/ssl-agreed"),
+                    &format!("https://localhost:{port}/ssl-server-name"),
+                    &format!("https://localhost:{port}/ssl-was-reused")
+                ])
+                .stdout(Stdio::piped())
+                .output()
+                .map(print_output)
+                .unwrap()
+                .stdout,
+            format!(
+                "hello world\n\
                      protocol:TLSv1.3,cipher:TLS_AES_256_GCM_SHA384\n\
                      server-name:localhost\n\
                      reused:{reused}\n"
-                )
-                .as_bytes(),
-            );
-            println!("PASS: resumption test for port={port} reused={reused}");
-        }
+            )
+            .as_bytes(),
+        );
+        println!("PASS: resumption test for port={port} reused={reused}");
     }
 
     // big download (throttled by curl to ensure non-blocking writes work)