Commit 4eff8b65 authored by Nick Mathewson's avatar Nick Mathewson 🦞
Browse files

When we mark a node as a sybil, mark it down and reset its uptime to 0 

This prevents bug 8147, where such nodes would accrue points towards
Guard, Fast, HSDir, and so on.

Fixes bug 8147.
parent 61995d3e

changes/bug8146_etc

+3 −0
Original line number Diff line number Diff line
@@ -8,3 +8,6 @@ 
    - Do not consider nodes with extremely low bandwidths when deciding

      thresholds for various directory flags. Another fix for 8145.



    - When marking a node as a likely sybil, reset its uptime metrics

      to zero, so that it cannot time towards getting marked as Guard,

      Stable, or HSDir. Fix for bug 8147.

src/or/dirserv.c

+5 −0
Original line number Diff line number Diff line
@@ -2776,6 +2776,11 @@ dirserv_generate_networkstatus_vote_obj(crypto_pk_t *private_key, 
  routers_sort_by_identity(routers);

  omit_as_sybil = get_possible_sybil_list(routers);



  DIGESTMAP_FOREACH(omit_as_sybil, sybil_id, void *, ignore) {

    (void) ignore;

    rep_hist_make_router_pessimal(sybil_id, now);

  } DIGESTMAP_FOREACH_END;



  dirserv_compute_performance_thresholds(rl, omit_as_sybil);



  routerstatuses = smartlist_new();

src/or/rephist.c

+15 −0
Original line number Diff line number Diff line
@@ -422,6 +422,21 @@ rep_hist_note_router_unreachable(const char *id, time_t when) 
  }

}



/** Mark a router with ID <b>id</b> as non-Running, and retroactively declare

 * that it has never been running: give it no stability and no WFU. */

void

rep_hist_make_router_pessimal(const char *id, time_t when)

{

  or_history_t *hist = get_or_history(id);

  tor_assert(hist);



  rep_hist_note_router_unreachable(id, when);

  mark_or_down(hist, when, 1);



  hist->weighted_run_length = 0;

  hist->weighted_uptime = 0;

}



/** Helper: Discount all old MTBF data, if it is time to do so.  Return

 * the time at which we should next discount MTBF data. */

time_t

src/or/rephist.h

+2 −0
Original line number Diff line number Diff line
@@ -24,6 +24,8 @@ void rep_hist_dump_stats(time_t now, int severity); 
void rep_hist_note_bytes_read(size_t num_bytes, time_t when);

void rep_hist_note_bytes_written(size_t num_bytes, time_t when);



void rep_hist_make_router_pessimal(const char *id, time_t when);



void rep_hist_note_dir_bytes_read(size_t num_bytes, time_t when);

void rep_hist_note_dir_bytes_written(size_t num_bytes, time_t when);