[tor-commits] [tor/master] Generate non-padding circpad events for PADDING_NEGOTIATE(D).

[nickm at torproject.org]

commit 5791bc9d768df8897bc471dba4def75c812cfcf2
Author: George Kadianakis <desnacked at riseup.net>
Date:   Fri Apr 12 23:42:46 2019 +0300

    Generate non-padding circpad events for PADDING_NEGOTIATE(D).
    
    As part of our machines, we need to know when a PADDING_NEGOATIATE(D) cell gets
    sent out, so we add an event for this.
---
 src/core/or/circuitpadding.c | 25 +++++++------------------
 1 file changed, 7 insertions(+), 18 deletions(-)

diff --git a/src/core/or/circuitpadding.c b/src/core/or/circuitpadding.c
index 48d0d4a95..1a46296d1 100644
--- a/src/core/or/circuitpadding.c
+++ b/src/core/or/circuitpadding.c
@@ -1737,13 +1737,12 @@ circpad_estimate_circ_rtt_on_send(circuit_t *circ,
      * to back. Stop estimating RTT in this case. Note that we only
      * stop RTT update if the circuit is opened, to allow for RTT estimates
      * of var cells during circ setup. */
-    mi->stop_rtt_update = 1;
-
-    if (!mi->rtt_estimate_usec) {
+    if (!mi->rtt_estimate_usec && !mi->stop_rtt_update) {
       static ratelim_t rtt_lim = RATELIM_INIT(600);
       log_fn_ratelim(&rtt_lim,LOG_NOTICE,LD_BUG,
         "Circuit sent two cells back to back before estimating RTT.");
     }
+    mi->stop_rtt_update = 1;
   }
 }
 
@@ -2256,13 +2255,6 @@ circpad_deliver_recognized_relay_cell_events(circuit_t *circ,
                                              uint8_t relay_command,
                                              crypt_path_t *layer_hint)
 {
-  /* Padding negotiate cells are ignored by the state machines
-   * for simplicity. */
-  if (relay_command == RELAY_COMMAND_PADDING_NEGOTIATE ||
-      relay_command == RELAY_COMMAND_PADDING_NEGOTIATED) {
-    return;
-  }
-
   if (relay_command == RELAY_COMMAND_DROP) {
     rep_hist_padding_count_read(PADDING_TYPE_DROP);
 
@@ -2299,16 +2291,12 @@ void
 circpad_deliver_sent_relay_cell_events(circuit_t *circ,
                                        uint8_t relay_command)
 {
-  /* Padding negotiate cells are ignored by the state machines
-   * for simplicity. */
-  if (relay_command == RELAY_COMMAND_PADDING_NEGOTIATE ||
-      relay_command == RELAY_COMMAND_PADDING_NEGOTIATED) {
-    return;
-  }
-
   /* RELAY_COMMAND_DROP is the multi-hop (aka circuit-level) padding cell in
    * tor. (CELL_PADDING is a channel-level padding cell, which is not relayed
-   * or processed here) */
+   * or processed here).
+   *
+   * We do generate events for PADDING_NEGOTIATE and PADDING_NEGOTIATED cells.
+   */
   if (relay_command == RELAY_COMMAND_DROP) {
     /* Optimization: The event for RELAY_COMMAND_DROP is sent directly
      * from circpad_send_padding_cell_for_callback(). This is to avoid
@@ -2823,6 +2811,7 @@ circpad_handle_padding_negotiate(circuit_t *circ, cell_t *cell)
                             const circpad_machine_spec_t *, m) {
       if (m->machine_num == negotiate->machine_type) {
         circpad_setup_machine_on_circ(circ, m);
+        circpad_cell_event_nonpadding_received(circ);
         goto done;
       }
     } SMARTLIST_FOREACH_END(m);