quic: fix up early QuicSession destroy

Send a stateless connection close if destroying while still in
initial crypto level (there are no encryption keys at this point
so we can't send a regular connection close)

Author: jasnell

src/quic/node_quic_session.cc

@@ -1997,6 +1997,22 @@ bool QuicSession::SendConnectionClose() {
   // serialize the connection close once but may end up transmitting
   // it multiple times; whereas for clients, we will serialize it
   // once and send once only.
+  QuicError error = last_error();
+
+  // If initial keys have not yet been installed, use the alternative
+  // ImmediateConnectionClose to send a stateless connection close to
+  // the peer.
+  if (crypto_context()->write_crypto_level() ==
+        NGTCP2_CRYPTO_LEVEL_INITIAL) {
+    socket()->ImmediateConnectionClose(
+        dcid(),
+        scid_,
+        local_address_,
+        remote_address_,
+        error.code);
+    return true;
+  }
+
   switch (crypto_context_->side()) {
     case NGTCP2_CRYPTO_SIDE_SERVER: {
       // If we're not already in the closing period,
@@ -2005,7 +2021,7 @@ bool QuicSession::SendConnectionClose() {
       // already started, skip this.
       if (!is_in_closing_period() &&
           (!WritePackets("server connection close - write packets") ||
-          !StartClosingPeriod())) {
+           !StartClosingPeriod())) {
           return false;
       }
 
@@ -2016,18 +2032,16 @@ bool QuicSession::SendConnectionClose() {
     }
     case NGTCP2_CRYPTO_SIDE_CLIENT: {
       UpdateIdleTimer();
-      auto packet = QuicPacket::Create(
-          "client connection close");
-      QuicError error = last_error();
+      auto packet = QuicPacket::Create("client connection close");
 
       // If we're not already in the closing period,
       // first attempt to write any pending packets, then
       // start the closing period. Note that the behavior
       // here is different than the server
       if (!is_in_closing_period() &&
-        !WritePackets("client connection close - write packets"))
+          !WritePackets("client connection close - write packets")) {
         return false;
-
+      }
       ssize_t nwrite =
           SelectCloseFn(error.family)(
             connection(),

src/quic/node_quic_socket.cc

@@ -693,16 +693,18 @@ bool QuicSocket::SendRetry(
 
 // Shutdown a connection prematurely, before a QuicSession is created.
 void QuicSocket::ImmediateConnectionClose(
-    const ngtcp2_pkt_hd& hd,
+    const QuicCID& scid,
+    const QuicCID& dcid,
     const SocketAddress& local_addr,
     const SocketAddress& remote_addr,
     int32_t reason) {
+  Debug(this, "Sending stateless connection close to %s", scid);
   auto packet = QuicPacket::Create("immediate connection close");
   ssize_t nwrite = ngtcp2_crypto_write_connection_close(
       packet->data(),
       packet->length(),
-      &hd.scid,
-      &hd.dcid,
+      scid.cid(),
+      dcid.cid(),
       reason);
   if (nwrite > 0) {
     packet->set_length(nwrite);
@@ -760,7 +762,12 @@ BaseObjectPtr<QuicSession> QuicSocket::AcceptInitialPacket(
           max_connections_per_host_) {
     Debug(this, "QuicSocket is busy or connection count exceeded");
     IncrementStat(&QuicSocketStats::server_busy_count);
-    ImmediateConnectionClose(hd, local_addr, remote_addr, NGTCP2_SERVER_BUSY);
+    ImmediateConnectionClose(
+      QuicCID(hd.scid),
+      QuicCID(hd.dcid),
+      local_addr,
+      remote_addr,
+      NGTCP2_SERVER_BUSY);
     return {};
   }
 
@@ -789,7 +796,11 @@ BaseObjectPtr<QuicSession> QuicSocket::AcceptInitialPacket(
                   token_secret_,
                   retry_token_expiration_)) {
             Debug(this, "Invalid retry token was detected. Failing.");
-            ImmediateConnectionClose(hd, local_addr, remote_addr);
+            ImmediateConnectionClose(
+                QuicCID(hd.scid),
+                QuicCID(hd.dcid),
+                local_addr,
+                remote_addr);
             return {};
           }
         }

src/quic/node_quic_socket.h

@@ -386,6 +386,13 @@ class QuicSocket : public AsyncWrap,
 
   inline void AddEndpoint(QuicEndpoint* endpoint, bool preferred = false);
 
+  void ImmediateConnectionClose(
+      const QuicCID& scid,
+      const QuicCID& dcid,
+      const SocketAddress& local_addr,
+      const SocketAddress& remote_addr,
+      int32_t reason = NGTCP2_INVALID_TOKEN);
+
  private:
   static void OnAlloc(
       uv_handle_t* handle,
@@ -405,11 +412,6 @@ class QuicSocket : public AsyncWrap,
       const SocketAddress& local_addr,
       const SocketAddress& remote_addr,
       unsigned int flags);
-  void ImmediateConnectionClose(
-      const ngtcp2_pkt_hd& hd,
-      const SocketAddress& local_addr,
-      const SocketAddress& remote_addr,
-      int32_t reason = NGTCP2_INVALID_TOKEN);
 
   BaseObjectPtr<QuicSession> AcceptInitialPacket(
       uint32_t version,