tls: allow enabling the TLS debug trace

Enable the same trace output that the OpenSSL s_client and s_server
support with their `-trace` option. This is invaluable when debugging
reports of TLS bugs as well as when debugging the internal TLS
implementation.

See:
- https://github.com/nodejs/node/issues/25383
- https://github.com/nodejs/node/issues/17936
- https://github.com/postmanlabs/postman-app-support/issues/5918#issuecomment-465311423

PR-URL: https://github.com/nodejs/node/pull/27376
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>

1 files changed, 58 insertions, 0 deletions

diff --git a/test/parallel/test-tls-enable-trace.js b/test/parallel/test-tls-enable-trace.js
new file mode 100644
index 0000000000..a3b1721ade
--- /dev/null
+++ b/test/parallel/test-tls-enable-trace.js
@@ -0,0 +1,58 @@
+// Flags: --expose-internals
+'use strict';
+const common = require('../common');
+if (!common.hasCrypto) common.skip('missing crypto');
+const fixtures = require('../common/fixtures');
+
+// Test enableTrace: option for TLS.
+
+const assert = require('assert');
+const { fork } = require('child_process');
+
+if (process.argv[2] === 'test')
+  return test();
+
+const binding = require('internal/test/binding').internalBinding;
+
+if (!binding('tls_wrap').HAVE_SSL_TRACE)
+  return common.skip('no SSL_trace() compiled into openssl');
+
+const child = fork(__filename, ['test'], { silent: true });
+
+let stderr = '';
+child.stderr.setEncoding('utf8');
+child.stderr.on('data', (data) => stderr += data);
+child.on('close', common.mustCall(() => {
+  assert(/Received Record/.test(stderr));
+  assert(/ClientHello/.test(stderr));
+}));
+
+// For debugging and observation of actual trace output.
+child.stderr.pipe(process.stderr);
+child.stdout.pipe(process.stdout);
+
+child.on('exit', common.mustCall((code) => {
+  assert.strictEqual(code, 0);
+}));
+
+function test() {
+  const {
+    connect, keys
+  } = require(fixtures.path('tls-connect'));
+
+  connect({
+    client: {
+      checkServerIdentity: (servername, cert) => { },
+      ca: `${keys.agent1.cert}\n${keys.agent6.ca}`,
+    },
+    server: {
+      cert: keys.agent6.cert,
+      key: keys.agent6.key,
+      enableTrace: true,
+    },
+  }, common.mustCall((err, pair, cleanup) => {
+    pair.client.conn.enableTrace();
+
+    return cleanup();
+  }));
+}