Commit 415caba9 authored by Nick Mathewson's avatar Nick Mathewson 🤹
Browse files

Merge remote branch 'arma/optimistic_server'

parents 737228ed c2775196

changes/prop174_server

0 → 100644
+6 −0
Original line number Diff line number Diff line 
  o Features:

    - Servers now accept and queue data on not-yet-connected

      streams.  Previously, such data wasn't allowed.  This forced

      clients to wait for a CONNECTED cell before sending their

      data, thus adding a round trip to stream setup.  (Patch from

      Ian Goldberg; implements the server side of Proposal 174.)

src/or/connection.c

+16 −3
Original line number Diff line number Diff line
@@ -3259,7 +3259,13 @@ _connection_write_to_buf_impl(const char *string, size_t len, 
    return;

  }



  /* If we receive optimistic data in the EXIT_CONN_STATE_RESOLVING

   * state, we don't want to try to write it right away, since

   * conn->write_event won't be set yet.  Otherwise, write data from

   * this conn as the socket is available. */

  if (conn->write_event) {

    connection_start_writing(conn);

  }

  if (zlib) {

    conn->outbuf_flushlen += buf_datalen(conn->outbuf) - old_datalen;

  } else {
@@ -3837,8 +3843,15 @@ assert_connection_ok(connection_t *conn, time_t now) 
    tor_assert(conn->s < 0);



  if (conn->outbuf_flushlen > 0) {

    tor_assert(connection_is_writing(conn) || conn->write_blocked_on_bw ||

            (CONN_IS_EDGE(conn) && TO_EDGE_CONN(conn)->edge_blocked_on_circ));

    /* With optimistic data, we may have queued data in

     * EXIT_CONN_STATE_RESOLVING while the conn is not yet marked to writing.

     * */

    tor_assert((conn->type == CONN_TYPE_EXIT &&

                conn->state == EXIT_CONN_STATE_RESOLVING) ||

               connection_is_writing(conn) ||

               conn->write_blocked_on_bw ||

               (CONN_IS_EDGE(conn) &&

                TO_EDGE_CONN(conn)->edge_blocked_on_circ));

  }



  if (conn->hold_open_until_flushed)

src/or/relay.c

+25 −4
Original line number Diff line number Diff line
@@ -1031,6 +1031,9 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ, 
  relay_header_t rh;

  unsigned domain = layer_hint?LD_APP:LD_EXIT;

  int reason;

  int optimistic_data = 0; /* Set to 1 if we receive data on a stream

                            * that's in the EXIT_CONN_STATE_RESOLVING

                            * or EXIT_CONN_STATE_CONNECTING states. */



  tor_assert(cell);

  tor_assert(circ);
@@ -1050,9 +1053,20 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ, 
  /* either conn is NULL, in which case we've got a control cell, or else

   * conn points to the recognized stream. */



  if (conn && !connection_state_is_open(TO_CONN(conn)))

  if (conn && !connection_state_is_open(TO_CONN(conn))) {

    if (conn->_base.type == CONN_TYPE_EXIT &&

        (conn->_base.state == EXIT_CONN_STATE_CONNECTING ||

         conn->_base.state == EXIT_CONN_STATE_RESOLVING) &&

        rh.command == RELAY_COMMAND_DATA) {

      /* Allow DATA cells to be delivered to an exit node in state

       * EXIT_CONN_STATE_CONNECTING or EXIT_CONN_STATE_RESOLVING.

       * This speeds up HTTP, for example. */

      optimistic_data = 1;

    } else {

      return connection_edge_process_relay_cell_not_open(

               &rh, cell, circ, conn, layer_hint);

    }

  }



  switch (rh.command) {

    case RELAY_COMMAND_DROP:
@@ -1119,7 +1133,14 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ, 
      stats_n_data_bytes_received += rh.length;

      connection_write_to_buf((char*)(cell->payload + RELAY_HEADER_SIZE),

                              rh.length, TO_CONN(conn));



      if (!optimistic_data) {

        /* Only send a SENDME if we're not getting optimistic data; otherwise

         * a SENDME could arrive before the CONNECTED.

         */

        connection_edge_consider_sending_sendme(conn);

      }



      return 0;

    case RELAY_COMMAND_END:

      reason = rh.length > 0 ?