Add working driver↔leaf TLS (hardware AES-GCM) to match prod encryption

Reviewed By: YifanYuan3

Differential Revision: D112488664

Author: excelle08

packages/feedsim/run.sh

@@ -823,6 +823,30 @@ main() {
     if [ "$mock_tls" = "1" ]; then
         export MOCK_TLS=1
     fi
+    # Driver↔Leaf TLS. When FEEDSIM_DRIVER_TLS=1 is passed in the environment,
+    # the DriverNodeRank client (reads FEEDSIM_DRIVER_TLS) wraps its
+    # bufferevents in OpenSSL, and the LeafNodeRank server needs a cert so
+    # FeedSimServer's accept path enables AsyncSSLSocket — wire the shared
+    # example cert/key into FEEDSIM_TLS_CERT/FEEDSIM_TLS_KEY. Both ends pin
+    # AES-GCM so the encrypted driver↔leaf volume registers as hardware crypto
+    # (matches prod's Rocket-over-TLS driver path). Default off. The LeafNodeRank
+    # server reads FEEDSIM_TLS_CERT/KEY from the exported env; the DriverNodeRank
+    # client is launched through search_qps.sh, which does not reliably forward
+    # the parent's exported env to the driver process, so FEEDSIM_DRIVER_TLS is
+    # also injected directly on the driver command line via `driver_bin`.
+    driver_bin="build/workloads/ranking/DriverNodeRank"
+    if [ "${FEEDSIM_DRIVER_TLS:-0}" = "1" ]; then
+        driver_cert_dir="${FEEDSIM_ROOT}/certs"
+        if [ ! -r "${driver_cert_dir}/example.crt" ] || [ ! -r "${driver_cert_dir}/example.key" ]; then
+            echo "ERROR: FEEDSIM_DRIVER_TLS=1 but ${driver_cert_dir}/example.{crt,key} not found" >&2
+            exit 1
+        fi
+        export FEEDSIM_TLS_CERT="${driver_cert_dir}/example.crt"
+        export FEEDSIM_TLS_KEY="${driver_cert_dir}/example.key"
+        export FEEDSIM_DRIVER_TLS=1
+        driver_bin="env FEEDSIM_DRIVER_TLS=1 build/workloads/ranking/DriverNodeRank"
+        echo "Driver↔Leaf TLS: ENABLED (cert=${driver_cert_dir}/example.crt, AES-GCM)"
+    fi
     # MOCK_ZSTD_FRAC env consumed by MockServicesClient::resolveZstdFraction.
     # Always export so the t43 c7 default 0.75 reaches the binary.
     export MOCK_ZSTD_FRAC="$mock_zstd_frac"
@@ -960,7 +984,7 @@ main() {
         echo "search_qps SLA: ${sla_arg}"
         # shellcheck disable=SC2086
         scripts/search_qps.sh -w 15 -f 300 -s "$sla_arg" -P "$LEAF_PID" -B "$BREAKDOWN_FOLDER" $qps_threshold_args $no_retry_args -o "${FEEDSIM_ROOT}/${result_filename}" -- \
-            build/workloads/ranking/DriverNodeRank \
+            $driver_bin \
                 --server "0.0.0.0:$port" \
                 --monitor_port "$client_monitor_port" \
                 --threads="${driver_threads}" \
@@ -974,7 +998,7 @@ main() {
         echo "search_qps SLA: ${sla_arg}"
         # shellcheck disable=SC2086
         scripts/search_qps.sh -a -w 15 -f 300 -s "$sla_arg" -P "$LEAF_PID" -B "$BREAKDOWN_FOLDER" $qps_threshold_args $no_retry_args -o "${FEEDSIM_ROOT}/${result_filename}" -- \
-            build/workloads/ranking/DriverNodeRank \
+            $driver_bin \
                 --monitor_port "$client_monitor_port" \
                 --server "0.0.0.0:$port" \
                 $client_feature_opts \
@@ -1000,7 +1024,7 @@ main() {
            -P "$LEAF_PID" -B "$BREAKDOWN_FOLDER" \
            $qps_threshold_args $no_retry_args \
            -o "${FEEDSIM_ROOT}/${result_filename}" \
-           -- build/workloads/ranking/DriverNodeRank \
+           -- $driver_bin \
                 --server "0.0.0.0:$port" \
                 --monitor_port "$client_monitor_port" \
                 --threads="${num_workers}" \

packages/feedsim/third_party/src/workloads/ranking/FeedSimDriver.cc

@@ -246,6 +246,18 @@ SSL_CTX* getDriverSslCtxOrNull() {
       return nullptr;
     }
     SSL_CTX_set_verify(ctx, SSL_VERIFY_NONE, nullptr);
+    // Restrict the offered ciphers to AES-GCM so the connection negotiates
+    // hardware AES (AES-NI on x86, ARMv8 crypto extensions on aarch64) via
+    // libcrypto, matching prod's cipher. Without this, OpenSSL may pick
+    // ChaCha20-Poly1305 (a NEON/integer cipher with no AES instructions),
+    // which reads as ~0% in the crypto instruction mix and runs the AEAD
+    // un-accelerated. Mirrors MockServicesClient's cipher pinning.
+    SSL_CTX_set_cipher_list(
+        ctx,
+        "ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:"
+        "ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256"); // TLS 1.2
+    SSL_CTX_set_ciphersuites(
+        ctx, "TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256"); // TLS 1.3
     std::cout << "FeedSimDriver: TLS enabled via FEEDSIM_DRIVER_TLS=1"
               << std::endl;
     return ctx;

packages/feedsim/third_party/src/workloads/ranking/FeedSimServer.cc

@@ -27,6 +27,7 @@
 
 #include <folly/MPMCQueue.h>
 #include <folly/container/F14Map.h>
+#include <folly/io/IOBuf.h>
 #include <folly/io/async/AsyncSSLSocket.h>
 #include <folly/io/async/AsyncServerSocket.h>
 #include <folly/io/async/AsyncSocket.h>
@@ -35,17 +36,30 @@
 #include <folly/io/async/EventBaseManager.h>
 #include <folly/io/async/SSLContext.h>
 
+#include <openssl/ssl.h>
+
 namespace feedsim {
 
+class ServerConnection;
+
 // ─── RequestContext implementation ──────────────────────────────────────────
 
 struct RequestContext::Impl {
-  // The socket fd to write the response back on.
-  // We use raw fd + write() because the response is a single small write
-  // and we want to avoid the complexity of AsyncSocket write callbacks.
+  // Plaintext path: the socket fd to write the response back on. We use raw
+  // fd + writev() because the response is a single small write and we want to
+  // avoid the complexity of AsyncSocket write callbacks.
   int fd;
   uint64_t received_time;
   bool response_sent;
+  // TLS path: raw fd writes bypass the TLS layer (they hit the TCP socket
+  // underneath AsyncSSLSocket, so the peer receives plaintext on an encrypted
+  // connection). When tls is true, the response must be written THROUGH the
+  // AsyncSSLSocket on its owning EventBase instead. sendResponse marshals the
+  // write onto evb and targets the connection via a weak_ptr so a response
+  // that completes after the connection closed is dropped safely.
+  bool tls = false;
+  folly::EventBase* evb = nullptr;
+  std::weak_ptr<ServerConnection> conn;
 };
 
 RequestContext::RequestContext(
@@ -69,6 +83,17 @@ RequestContext::RequestContext(RequestContext&& other) noexcept
 
 RequestContext::~RequestContext() = default;
 
+// Marshals a TLS response (header+payload already framed in buf) onto the
+// connection's EventBase and writes it through the AsyncSSLSocket. Defined
+// after ServerConnection (needs its full type); declared here so sendResponse
+// can call it. Safe if the connection has already closed.
+namespace {
+void enqueueTlsResponse(
+    std::weak_ptr<ServerConnection> conn,
+    folly::EventBase* evb,
+    std::unique_ptr<folly::IOBuf> buf);
+} // namespace
+
 void RequestContext::sendResponse(const void* data, uint32_t data_length) {
   if (!impl_ || impl_->response_sent) return;
   impl_->response_sent = true;
@@ -85,7 +110,21 @@ void RequestContext::sendResponse(const void* data, uint32_t data_length) {
 
   ResponsePacketHeader net = responseToNetwork(hdr);
 
-  // Use writev to send header + payload atomically
+  if (impl_->tls) {
+    // Raw fd writes bypass TLS, so build one contiguous frame (copying the
+    // payload synchronously — the caller may free `data` after we return) and
+    // hand it to the connection's EventBase to write through AsyncSSLSocket.
+    auto buf = folly::IOBuf::create(sizeof(net) + data_length);
+    memcpy(buf->writableData(), &net, sizeof(net));
+    if (data_length > 0) {
+      memcpy(buf->writableData() + sizeof(net), data, data_length);
+    }
+    buf->append(sizeof(net) + data_length);
+    enqueueTlsResponse(impl_->conn, impl_->evb, std::move(buf));
+    return;
+  }
+
+  // Plaintext path (unchanged): use writev to send header + payload atomically
   struct iovec iov[2];
   iov[0].iov_base = &net;
   iov[0].iov_len = sizeof(net);
@@ -122,15 +161,19 @@ void RequestContext::sendResponse(const void* data, uint32_t data_length) {
 
 // ─── ServerConnection: handles framing for one client connection ────────────
 
-class ServerConnection : public folly::AsyncTransport::ReadCallback {
+class ServerConnection
+    : public folly::AsyncTransport::ReadCallback,
+      public std::enable_shared_from_this<ServerConnection> {
  public:
   ServerConnection(
       folly::AsyncSocket::UniquePtr socket,
       int thread_id,
-      const folly::F14FastMap<uint32_t, QueryCallback>& callbacks)
+      const folly::F14FastMap<uint32_t, QueryCallback>& callbacks,
+      bool tls)
       : socket_(std::move(socket)),
         thread_id_(thread_id),
         callbacks_(callbacks),
+        tls_(tls),
         read_buf_(nullptr),
         read_buf_size_(0),
         data_offset_(0) {
@@ -144,6 +187,17 @@ class ServerConnection : public folly::AsyncTransport::ReadCallback {
     delete[] read_buf_;
   }
 
+  // Called once right after construction so the connection keeps itself alive
+  // while registered as the socket's read callback (broken on EOF/error).
+  void attachSelf(std::shared_ptr<ServerConnection> self) {
+    self_ = std::move(self);
+  }
+
+  // Writes a fully-framed TLS response through the AsyncSSLSocket. MUST be
+  // invoked on the socket's EventBase thread. Defined out-of-line below
+  // (needs TlsWriteCallback's full definition).
+  void writeResponse(std::unique_ptr<folly::IOBuf> buf);
+
   // AsyncTransport::ReadCallback
   void getReadBuffer(void** bufReturn, size_t* lenReturn) override {
     // Grow buffer if needed
@@ -165,15 +219,14 @@ class ServerConnection : public folly::AsyncTransport::ReadCallback {
   }
 
   void readEOF() noexcept override {
-    // Client disconnected
-    socket_->close();
-    // Self-delete via destroy callback (see below)
-    delete this;
+    // Client disconnected. Break the self-reference so the object is destroyed
+    // once any in-flight TLS write callbacks release their refs. Hold a local
+    // ref so `this` stays valid until we return from the callback.
+    close();
   }
 
   void readErr(const folly::AsyncSocketException& ex) noexcept override {
-    socket_->close();
-    delete this;
+    close();
   }
 
  private:
@@ -199,6 +252,13 @@ class ServerConnection : public folly::AsyncTransport::ReadCallback {
         impl->fd = socket_->getNetworkSocket().toFd();
         impl->received_time = getTimeNano();
         impl->response_sent = false;
+        impl->tls = tls_;
+        if (tls_) {
+          // The response may be produced asynchronously on a pool thread; it
+          // must be written back through the AsyncSSLSocket on this EventBase.
+          impl->evb = socket_->getEventBase();
+          impl->conn = weak_from_this();
+        }
 
         RequestContext ctx(
             hdr.type, hdr.request_id, hdr.start_time,
@@ -216,14 +276,112 @@ class ServerConnection : public folly::AsyncTransport::ReadCallback {
     }
   }
 
+  void close() {
+    socket_->close();
+    // Hold a local ref so `this` survives until we return, then drop the
+    // self-reference. If TLS write callbacks are still outstanding they hold
+    // their own refs and the object lives until they complete.
+    auto keepalive = shared_from_this();
+    self_.reset();
+  }
+
   folly::AsyncSocket::UniquePtr socket_;
   int thread_id_;
   const folly::F14FastMap<uint32_t, QueryCallback>& callbacks_;
+  bool tls_;
+  std::shared_ptr<ServerConnection> self_;
   uint8_t* read_buf_;
   size_t read_buf_size_;
   size_t data_offset_;
 };
 
+// ─── TLS response write path ────────────────────────────────────────────────
+
+namespace {
+// Keeps the connection alive (via shared_ptr) until the AsyncSSLSocket finishes
+// encrypting and writing the response, then deletes itself.
+class TlsWriteCallback : public folly::AsyncWriter::WriteCallback {
+ public:
+  explicit TlsWriteCallback(std::shared_ptr<ServerConnection> conn)
+      : conn_(std::move(conn)) {}
+  void writeSuccess() noexcept override { delete this; }
+  void writeErr(
+      size_t /*bytesWritten*/,
+      const folly::AsyncSocketException& /*ex*/) noexcept override {
+    delete this;
+  }
+
+ private:
+  std::shared_ptr<ServerConnection> conn_;
+};
+
+void enqueueTlsResponse(
+    std::weak_ptr<ServerConnection> weak,
+    folly::EventBase* evb,
+    std::unique_ptr<folly::IOBuf> buf) {
+  if (evb == nullptr) {
+    return;
+  }
+  evb->runInEventBaseThread(
+      [weak = std::move(weak), buf = std::move(buf)]() mutable {
+        auto conn = weak.lock();
+        if (!conn) {
+          return; // connection closed before the response was ready
+        }
+        conn->writeResponse(std::move(buf));
+      });
+}
+} // namespace
+
+void ServerConnection::writeResponse(std::unique_ptr<folly::IOBuf> buf) {
+  // Runs on the socket's EventBase thread. The callback holds a ref that keeps
+  // this connection alive until the encrypted write completes.
+  auto* cb = new TlsWriteCallback(shared_from_this());
+  socket_->writeChain(cb, std::move(buf));
+}
+
+// ─── SslAcceptor: drives the server-side TLS handshake before wire reads ─────
+
+// A folly server-side AsyncSSLSocket does NOT auto-handshake when you merely
+// setReadCB — sslAccept() must be called to run the handshake. Until it
+// completes the socket can neither decrypt requests nor send responses. This
+// helper owns the socket during the handshake and, on success, hands it to a
+// ServerConnection (which then starts reading). It self-deletes either way.
+class SslAcceptor : public folly::AsyncSSLSocket::HandshakeCB {
+ public:
+  SslAcceptor(
+      folly::AsyncSSLSocket::UniquePtr socket,
+      int thread_id,
+      const folly::F14FastMap<uint32_t, QueryCallback>& callbacks)
+      : socket_(std::move(socket)),
+        thread_id_(thread_id),
+        callbacks_(callbacks) {}
+
+  void start() {
+    auto* raw = socket_.get();
+    raw->sslAccept(this);
+  }
+
+  void handshakeSuc(folly::AsyncSSLSocket* /*sock*/) noexcept override {
+    folly::AsyncSocket::UniquePtr base(socket_.release());
+    auto conn = std::make_shared<ServerConnection>(
+        std::move(base), thread_id_, callbacks_, /*tls=*/true);
+    conn->attachSelf(conn);
+    delete this;
+  }
+
+  void handshakeErr(
+      folly::AsyncSSLSocket* /*sock*/,
+      const folly::AsyncSocketException& /*ex*/) noexcept override {
+    delete this; // socket_ (and the fd) torn down with it
+  }
+
+ private:
+  folly::AsyncSSLSocket::UniquePtr socket_;
+  int thread_id_;
+  const folly::F14FastMap<uint32_t, QueryCallback>& callbacks_;
+};
+
 // ─── WorkerThread ───────────────────────────────────────────────────────────
 
 struct WorkerThread {
@@ -275,20 +433,25 @@ class AcceptCallback : public folly::AsyncServerSocket::AcceptCallback {
     worker->evb->runInEventBaseThread(
         [fd, thread_id = worker->thread_id, &callbacks = callbacks_,
          evb = worker->evb.get(), ssl_ctx]() {
-          folly::AsyncSocket::UniquePtr socket;
           if (ssl_ctx) {
-            // AsyncSSLSocket server-side: pass true for the server flag.
-            // The handshake is initiated lazily on first read/write,
-            // matching the existing client's connect-then-write pattern.
+            // AsyncSSLSocket server-side: pass true for the server flag, then
+            // drive the handshake via sslAccept (SslAcceptor). The
+            // ServerConnection is created only after the handshake succeeds —
+            // reading/writing before that would see undecrypted bytes.
             folly::AsyncSSLSocket::UniquePtr ssl_sock(new folly::AsyncSSLSocket(
                 ssl_ctx, evb, folly::NetworkSocket::fromFd(fd), true));
-            socket.reset(ssl_sock.release());
+            auto* acceptor =
+                new SslAcceptor(std::move(ssl_sock), thread_id, callbacks);
+            acceptor->start();
           } else {
-            socket = folly::AsyncSocket::newSocket(
+            folly::AsyncSocket::UniquePtr socket = folly::AsyncSocket::newSocket(
                 evb, folly::NetworkSocket::fromFd(fd));
+            // ServerConnection keeps itself alive via a self-reference (set by
+            // attachSelf) until EOF/error.
+            auto conn = std::make_shared<ServerConnection>(
+                std::move(socket), thread_id, callbacks, /*tls=*/false);
+            conn->attachSelf(conn);
           }
-          // ServerConnection self-manages its lifetime
-          new ServerConnection(std::move(socket), thread_id, callbacks);
         });
   }
 
@@ -433,6 +596,17 @@ void FeedSimServer::run() {
         auto ctx = std::make_shared<folly::SSLContext>();
         ctx->loadCertificate(cert_env);
         ctx->loadPrivateKey(key_env);
+        // Restrict to AES-GCM so the negotiated cipher uses hardware AES
+        // (AES-NI / ARMv8 crypto extensions) via libcrypto, matching prod
+        // and the driver's pinned ciphers. Without this the server may accept
+        // ChaCha20-Poly1305, which has no AES instructions and reads as ~0%
+        // crypto in the instruction mix.
+        ctx->setCiphersOrThrow(
+            "ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:"
+            "ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256"); // TLS 1.2
+        SSL_CTX_set_ciphersuites(
+            ctx->getSSLCtx(),
+            "TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256"); // TLS 1.3
         // No ALPN — FeedSim uses its own custom binary protocol over the
         // TLS-wrapped socket, not Rocket. The client similarly does not
         // advertise ALPN.