Commit c40d53ab authored by Nick Mathewson's avatar Nick Mathewson 🤹
Browse files

Merge branch 'pr_719_squashed_040' into maint-0.4.0

parents 968d2b87 ff410ede

changes/bug29204

0 → 100644
+4 −0
Original line number Diff line number Diff line 
  o Minor bugfixes (circuitpadding):

    - Inspect circuit-level cell queue before sending padding, to avoid

      sending padding while too much data is queued. Fixes bug 29204;

      bugfix on 0.4.0.1-alpha.

src/core/or/circuitpadding.c

+17 −4
Original line number Diff line number Diff line
@@ -61,6 +61,7 @@ 
#include "core/or/crypt_path_st.h"

#include "core/or/circuit_st.h"

#include "core/or/origin_circuit_st.h"

#include "core/or/or_circuit_st.h"

#include "feature/nodelist/routerstatus_st.h"

#include "feature/nodelist/node_st.h"

#include "core/or/cell_st.h"
@@ -81,6 +82,7 @@ static double circpad_distribution_sample(circpad_distribution_t dist); 
/** Cached consensus params */

static uint8_t circpad_global_max_padding_percent;

static uint16_t circpad_global_allowed_cells;

static uint16_t circpad_max_circ_queued_cells;



/** Global cell counts, for rate limiting */

static uint64_t circpad_global_padding_sent;
@@ -1027,10 +1029,17 @@ circpad_send_padding_cell_for_callback(circpad_machine_state_t *mi) 
  } else {

    // If we're a non-origin circ, we can just send from here as if we're the

    // edge.

    if (TO_OR_CIRCUIT(circ)->p_chan_cells.n <= circpad_max_circ_queued_cells) {

      log_fn(LOG_INFO,LD_CIRC,

             "Callback: Sending padding to non-origin circuit.");

      relay_send_command_from_edge(0, mi->on_circ, RELAY_COMMAND_DROP, NULL,

                                   0, NULL);

    } else {

      static ratelim_t cell_lim = RATELIM_INIT(600);

      log_fn_ratelim(&cell_lim,LOG_NOTICE,LD_CIRC,

                     "Too many cells (%d) in circ queue to send padding.",

                      TO_OR_CIRCUIT(circ)->p_chan_cells.n);

    }

  }



  rep_hist_padding_count_write(PADDING_TYPE_DROP);
@@ -1093,6 +1102,10 @@ circpad_new_consensus_params(const networkstatus_t *ns) 
  circpad_global_max_padding_percent =

      networkstatus_get_param(ns, "circpad_global_max_padding_pct",

         0, 0, 100);



  circpad_max_circ_queued_cells =

      networkstatus_get_param(ns, "circpad_max_circ_queued_cells",

         CIRCWINDOW_START_MAX, 0, 50*CIRCWINDOW_START_MAX);

}



/**