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@@ -67,7 +67,9 @@ static int entry_guard_inc_circ_attempt_count(entry_guard_t *guard);
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static void pathbias_count_build_success(origin_circuit_t *circ);
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static void pathbias_count_successful_close(origin_circuit_t *circ);
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static void pathbias_count_collapse(origin_circuit_t *circ);
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-static void pathbias_count_unusable(origin_circuit_t *circ);
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+static void pathbias_count_use_failed(origin_circuit_t *circ);
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+static int pathbias_check_use_rate(entry_guard_t *guard);
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+static int pathbias_check_close_rate(entry_guard_t *guard);
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/** This function tries to get a channel to the specified endpoint,
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* and then calls command_setup_channel() to give it the right
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@@ -1210,19 +1212,65 @@ pathbias_get_mult_factor(const or_options_t *options)
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pathbias_get_scale_factor(options));
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}
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+/** The minimum number of circuit usage attempts before we start
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+ * thinking about warning about path use bias and dropping guards */
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+static int
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+pathbias_get_min_use(const or_options_t *options)
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+{
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+#define DFLT_PATH_BIAS_MIN_USE 20
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+ if (options->PathBiasUseThreshold >= 3)
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+ return options->PathBiasUseThreshold;
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+ else
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+ return networkstatus_get_param(NULL, "pb_minuse",
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+ DFLT_PATH_BIAS_MIN_USE,
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+ 3, INT32_MAX);
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+}
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+
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+/** The circuit use success rate below which we issue a notice */
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+static double
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+pathbias_get_notice_use_rate(const or_options_t *options)
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+{
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+#define DFLT_PATH_BIAS_NOTICE_USE_PCT 90
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+ if (options->PathBiasNoticeUseRate >= 0.0)
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+ return options->PathBiasNoticeUseRate;
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+ else
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+ return networkstatus_get_param(NULL, "pb_noticeusepct",
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+ DFLT_PATH_BIAS_NOTICE_USE_PCT,
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+ 0, 100)/100.0;
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+}
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+
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/**
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- * If this parameter is set to a true value (default), we use the
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- * successful_circuits_closed. Otherwise, we use the success_count.
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+ * The extreme use rate is the rate at which we would drop the guard,
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+ * if pb_dropguard is also set. Otherwise we just warn.
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+ */
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+double
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+pathbias_get_extreme_use_rate(const or_options_t *options)
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+{
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+#define DFLT_PATH_BIAS_EXTREME_USE_PCT 70
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+ if (options->PathBiasExtremeUseRate >= 0.0)
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+ return options->PathBiasExtremeUseRate;
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+ else
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+ return networkstatus_get_param(NULL, "pb_extremeusepct",
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+ DFLT_PATH_BIAS_EXTREME_USE_PCT,
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+ 0, 100)/100.0;
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+}
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+
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+/**
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+ * This is the number of circuits at which we scale our
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+ * use counts by mult_factor/scale_factor. Note, this count is
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+ * not exact, as we only perform the scaling in the event
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+ * of no integer truncation.
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*/
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static int
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-pathbias_use_close_counts(const or_options_t *options)
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+pathbias_get_scale_use_threshold(const or_options_t *options)
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{
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-#define DFLT_PATH_BIAS_USE_CLOSE_COUNTS 1
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- if (options->PathBiasUseCloseCounts >= 0)
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- return options->PathBiasUseCloseCounts;
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+#define DFLT_PATH_BIAS_SCALE_USE_THRESHOLD 100
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+ if (options->PathBiasScaleUseThreshold >= 10)
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+ return options->PathBiasScaleUseThreshold;
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else
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- return networkstatus_get_param(NULL, "pb_useclosecounts",
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- DFLT_PATH_BIAS_USE_CLOSE_COUNTS, 0, 1);
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+ return networkstatus_get_param(NULL, "pb_scaleuse",
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+ DFLT_PATH_BIAS_SCALE_USE_THRESHOLD,
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+ 10, INT32_MAX);
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}
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/**
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@@ -1238,10 +1286,14 @@ pathbias_state_to_string(path_state_t state)
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return "build attempted";
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case PATH_STATE_BUILD_SUCCEEDED:
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return "build succeeded";
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+ case PATH_STATE_USE_ATTEMPTED:
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+ return "use attempted";
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case PATH_STATE_USE_SUCCEEDED:
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return "use succeeded";
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case PATH_STATE_USE_FAILED:
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return "use failed";
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+ case PATH_STATE_ALREADY_COUNTED:
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+ return "already counted";
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}
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return "unknown";
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@@ -1338,7 +1390,7 @@ pathbias_should_count(origin_circuit_t *circ)
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* Also check for several potential error cases for bug #6475.
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*/
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static int
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-pathbias_count_circ_attempt(origin_circuit_t *circ)
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+pathbias_count_build_attempt(origin_circuit_t *circ)
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{
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#define CIRC_ATTEMPT_NOTICE_INTERVAL (600)
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static ratelim_t circ_attempt_notice_limit =
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@@ -1504,6 +1556,126 @@ pathbias_count_build_success(origin_circuit_t *circ)
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}
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}
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+/**
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+ * Record an attempt to use a circuit. Changes the circuit's
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+ * path state and update its guard's usage counter.
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+ *
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+ * Used for path bias usage accounting.
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+ */
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+void
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+pathbias_count_use_attempt(origin_circuit_t *circ)
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+{
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+ entry_guard_t *guard;
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+
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+ if (!pathbias_should_count(circ)) {
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+ return;
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+ }
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+
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+ if (circ->path_state < PATH_STATE_BUILD_SUCCEEDED) {
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+ log_notice(LD_BUG,
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+ "Used circuit is in strange path state %s. "
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+ "Circuit is a %s currently %s.",
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+ pathbias_state_to_string(circ->path_state),
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+ circuit_purpose_to_string(circ->base_.purpose),
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+ circuit_state_to_string(circ->base_.state));
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+ } else if (circ->path_state < PATH_STATE_USE_ATTEMPTED) {
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+ guard = entry_guard_get_by_id_digest(
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+ circ->cpath->extend_info->identity_digest);
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+ if (guard) {
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+ pathbias_check_use_rate(guard);
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+ guard->use_attempts++;
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+
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+ log_debug(LD_CIRC, "Marked circuit %d as used for guard %s=%s.",
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+ circ->global_identifier, guard->nickname,
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+ hex_str(guard->identity, DIGEST_LEN));
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+ }
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+
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+ circ->path_state = PATH_STATE_USE_ATTEMPTED;
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+ } else {
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+ /* Harmless but educational log message */
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+ log_info(LD_CIRC,
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+ "Used circuit %d is already in path state %s. "
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+ "Circuit is a %s currently %s.",
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+ circ->global_identifier,
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+ pathbias_state_to_string(circ->path_state),
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+ circuit_purpose_to_string(circ->base_.purpose),
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+ circuit_state_to_string(circ->base_.state));
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+ }
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+
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+ return;
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+}
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+
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+/**
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+ * Check the circuit's path stat is appropriate and it as successfully
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+ * used.
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+ *
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+ * We don't actually increment the guard's counters until
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+ * pathbias_check_close().
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+ *
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+ * Used for path bias usage accounting.
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+ */
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+void
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+pathbias_mark_use_success(origin_circuit_t *circ)
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+{
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+ if (!pathbias_should_count(circ)) {
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+ return;
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+ }
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+
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+ if (circ->path_state < PATH_STATE_USE_ATTEMPTED) {
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+ log_notice(LD_BUG,
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+ "Used circuit %d is in strange path state %s. "
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+ "Circuit is a %s currently %s.",
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+ circ->global_identifier,
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+ pathbias_state_to_string(circ->path_state),
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+ circuit_purpose_to_string(circ->base_.purpose),
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+ circuit_state_to_string(circ->base_.state));
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+
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+ pathbias_count_use_attempt(circ);
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+ }
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+
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+ /* We don't do any accounting at the guard until actual circuit close */
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+ circ->path_state = PATH_STATE_USE_SUCCEEDED;
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+
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+ return;
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+}
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+
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+/**
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+ * Actually count a circuit success towards a guard's usage counters
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+ * if the path state is appropriate.
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+ */
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+static void
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+pathbias_count_use_success(origin_circuit_t *circ)
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+{
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+ entry_guard_t *guard;
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+
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+ if (!pathbias_should_count(circ)) {
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+ return;
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+ }
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+
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+ if (circ->path_state != PATH_STATE_USE_SUCCEEDED) {
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+ log_notice(LD_BUG,
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+ "Successfully used circuit %d is in strange path state %s. "
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+ "Circuit is a %s currently %s.",
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+ circ->global_identifier,
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+ pathbias_state_to_string(circ->path_state),
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+ circuit_purpose_to_string(circ->base_.purpose),
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+ circuit_state_to_string(circ->base_.state));
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+ } else {
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+ guard = entry_guard_get_by_id_digest(
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+ circ->cpath->extend_info->identity_digest);
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+ if (guard) {
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+ guard->use_successes++;
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+
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+ log_debug(LD_CIRC,
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+ "Marked circuit %d as used successfully for guard %s=%s.",
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+ circ->global_identifier, guard->nickname,
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+ hex_str(guard->identity, DIGEST_LEN));
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+ }
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+ }
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+
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+ return;
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+}
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+
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/**
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* Send a probe down a circuit that the client attempted to use,
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* but for which the stream timed out/failed. The probe is a
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@@ -1648,7 +1820,7 @@ pathbias_check_probe_response(circuit_t *circ, const cell_t *cell)
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/* Check nonce */
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if (ipv4_host == ocirc->pathbias_probe_nonce) {
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- ocirc->path_state = PATH_STATE_USE_SUCCEEDED;
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+ pathbias_mark_use_success(ocirc);
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circuit_mark_for_close(circ, END_CIRC_REASON_FINISHED);
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log_info(LD_CIRC,
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"Got valid path bias probe back for circ %d, stream %d.",
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@@ -1691,24 +1863,11 @@ pathbias_check_close(origin_circuit_t *ocirc, int reason)
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return 0;
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}
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- if (ocirc->path_state == PATH_STATE_BUILD_SUCCEEDED) {
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- if (circ->timestamp_dirty) {
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- if (pathbias_send_usable_probe(circ) == 0)
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- return -1;
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- else
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- pathbias_count_unusable(ocirc);
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-
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- /* Any circuit where there were attempted streams but no successful
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- * streams could be bias */
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- log_info(LD_CIRC,
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- "Circuit %d closed without successful use for reason %d. "
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- "Circuit purpose %d currently %d,%s. Len %d.",
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- ocirc->global_identifier,
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- reason, circ->purpose, ocirc->has_opened,
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- circuit_state_to_string(circ->state),
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- ocirc->build_state->desired_path_len);
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-
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- } else {
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+ switch (ocirc->path_state) {
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+ /* If the circuit was closed after building, but before use, we need
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+ * to ensure we were the ones who tried to close it (and not a remote
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+ * actor). */
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+ case PATH_STATE_BUILD_SUCCEEDED:
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if (reason & END_CIRC_REASON_FLAG_REMOTE) {
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/* Remote circ close reasons on an unused circuit all could be bias */
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log_info(LD_CIRC,
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@@ -1739,11 +1898,41 @@ pathbias_check_close(origin_circuit_t *ocirc, int reason)
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} else {
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pathbias_count_successful_close(ocirc);
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}
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- }
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- } else if (ocirc->path_state == PATH_STATE_USE_SUCCEEDED) {
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- pathbias_count_successful_close(ocirc);
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+ break;
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+
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+ /* If we tried to use a circuit but failed, we should probe it to ensure
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+ * it has not been tampered with. */
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+ case PATH_STATE_USE_ATTEMPTED:
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+ /* XXX: Only probe and/or count failure if the network is live?
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+ * What about clock jumps/suspends? */
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+ if (pathbias_send_usable_probe(circ) == 0)
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+ return -1;
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+ else
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+ pathbias_count_use_failed(ocirc);
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+
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+ /* Any circuit where there were attempted streams but no successful
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+ * streams could be bias */
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+ log_info(LD_CIRC,
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+ "Circuit %d closed without successful use for reason %d. "
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+ "Circuit purpose %d currently %d,%s. Len %d.",
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+ ocirc->global_identifier,
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+ reason, circ->purpose, ocirc->has_opened,
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+ circuit_state_to_string(circ->state),
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+ ocirc->build_state->desired_path_len);
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+ break;
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+
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+ case PATH_STATE_USE_SUCCEEDED:
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+ pathbias_count_successful_close(ocirc);
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+ pathbias_count_use_success(ocirc);
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+ break;
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+
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+ default:
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+ // Other states are uninteresting. No stats to count.
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+ break;
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}
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+ ocirc->path_state = PATH_STATE_ALREADY_COUNTED;
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+
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return 0;
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}
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@@ -1792,6 +1981,7 @@ static void
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pathbias_count_collapse(origin_circuit_t *circ)
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{
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entry_guard_t *guard = NULL;
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+
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if (!pathbias_should_count(circ)) {
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return;
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}
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@@ -1816,8 +2006,13 @@ pathbias_count_collapse(origin_circuit_t *circ)
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}
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}
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+/**
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+ * Count a known failed circuit (because we could not probe it).
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+ *
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+ * This counter is informational.
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+ */
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static void
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-pathbias_count_unusable(origin_circuit_t *circ)
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+pathbias_count_use_failed(origin_circuit_t *circ)
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{
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entry_guard_t *guard = NULL;
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if (!pathbias_should_count(circ)) {
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@@ -1886,7 +2081,7 @@ pathbias_count_timeout(origin_circuit_t *circ)
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* of the doubt.
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*/
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double
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-pathbias_get_closed_count(entry_guard_t *guard)
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+pathbias_get_close_success_count(entry_guard_t *guard)
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{
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circuit_t *circ;
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int open_circuits = 0;
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@@ -1903,7 +2098,12 @@ pathbias_get_closed_count(entry_guard_t *guard)
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if (!ocirc->cpath || !ocirc->cpath->extend_info)
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continue;
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+ /* Don't count known failed or already counted circuits */
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+ if (ocirc->path_state >= PATH_STATE_USE_FAILED)
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+ continue;
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+
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if (ocirc->path_state >= PATH_STATE_BUILD_SUCCEEDED &&
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+ pathbias_should_count(ocirc) &&
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fast_memeq(guard->identity,
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ocirc->cpath->extend_info->identity_digest,
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DIGEST_LEN)) {
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@@ -1915,51 +2115,201 @@ pathbias_get_closed_count(entry_guard_t *guard)
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}
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/**
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- * This function checks the consensus parameters to decide
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- * if it should return guard->circ_successes or
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- * guard->successful_circuits_closed.
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+ * Return the number of circuits counted as successfully used
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+ * this guard.
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+ *
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+ * Also add in the currently open circuits that we are attempting
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+ * to use to give them the benefit of the doubt.
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*/
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double
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-pathbias_get_success_count(entry_guard_t *guard)
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+pathbias_get_use_success_count(entry_guard_t *guard)
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{
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- if (pathbias_use_close_counts(get_options())) {
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- return pathbias_get_closed_count(guard);
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- } else {
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- return guard->circ_successes;
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+ circuit_t *circ = global_circuitlist;
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+ int open_circuits = 0;
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+
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+ /* Count currently open circuits. Give them the benefit of the doubt */
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+ for ( ; circ; circ = circ->next) {
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+ origin_circuit_t *ocirc = NULL;
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+ if (!CIRCUIT_IS_ORIGIN(circ) || /* didn't originate here */
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+ circ->marked_for_close) /* already counted */
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+ continue;
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+
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+ ocirc = TO_ORIGIN_CIRCUIT(circ);
|
|
|
+
|
|
|
+ if (!ocirc->cpath || !ocirc->cpath->extend_info)
|
|
|
+ continue;
|
|
|
+
|
|
|
+ /* Don't count known failed or already counted circuits */
|
|
|
+ if (ocirc->path_state >= PATH_STATE_USE_FAILED)
|
|
|
+ continue;
|
|
|
+
|
|
|
+ if (ocirc->path_state >= PATH_STATE_USE_ATTEMPTED &&
|
|
|
+ pathbias_should_count(ocirc) &&
|
|
|
+ fast_memeq(guard->identity,
|
|
|
+ ocirc->cpath->extend_info->identity_digest,
|
|
|
+ DIGEST_LEN)) {
|
|
|
+ open_circuits++;
|
|
|
+ }
|
|
|
}
|
|
|
+
|
|
|
+ return guard->use_successes + open_circuits;
|
|
|
}
|
|
|
|
|
|
-/** Increment the number of times we successfully extended a circuit to
|
|
|
- * <b>guard</b>, first checking if the failure rate is high enough that
|
|
|
- * we should eliminate the guard. Return -1 if the guard looks no good;
|
|
|
- * return 0 if the guard looks fine.
|
|
|
+/**
|
|
|
+ * Check the path bias use rate against our consensus parameter limits.
|
|
|
+ *
|
|
|
+ * Emits a log message if the use success rates are too low.
|
|
|
+ *
|
|
|
+ * If pathbias_get_dropguards() is set, we also disable the use of
|
|
|
+ * very failure prone guards.
|
|
|
+ *
|
|
|
+ * Returns -1 if we decided to disable the guard, 0 otherwise.
|
|
|
*/
|
|
|
static int
|
|
|
-entry_guard_inc_circ_attempt_count(entry_guard_t *guard)
|
|
|
+pathbias_check_use_rate(entry_guard_t *guard)
|
|
|
{
|
|
|
const or_options_t *options = get_options();
|
|
|
|
|
|
- entry_guards_changed();
|
|
|
+ if (guard->use_attempts > pathbias_get_min_use(options)) {
|
|
|
+ /* Note: We rely on the < comparison here to allow us to set a 0
|
|
|
+ * rate and disable the feature entirely. If refactoring, don't
|
|
|
+ * change to <= */
|
|
|
+ if (pathbias_get_use_success_count(guard)/guard->use_attempts
|
|
|
+ < pathbias_get_extreme_use_rate(options)) {
|
|
|
+ /* Dropping is currently disabled by default. */
|
|
|
+ if (pathbias_get_dropguards(options)) {
|
|
|
+ if (!guard->path_bias_disabled) {
|
|
|
+ log_warn(LD_CIRC,
|
|
|
+ "Your Guard %s=%s is failing to carry an extremely large "
|
|
|
+ "amount of stream on its circuits. "
|
|
|
+ "To avoid potential route manipluation attacks, Tor has "
|
|
|
+ "disabled use of this guard. "
|
|
|
+ "Use counts are %ld/%ld. Success counts are %ld/%ld. "
|
|
|
+ "%ld circuits completed, %ld were unusable, %ld collapsed, "
|
|
|
+ "and %ld timed out. "
|
|
|
+ "For reference, your timeout cutoff is %ld seconds.",
|
|
|
+ guard->nickname, hex_str(guard->identity, DIGEST_LEN),
|
|
|
+ tor_lround(pathbias_get_use_success_count(guard)),
|
|
|
+ tor_lround(guard->use_attempts),
|
|
|
+ tor_lround(pathbias_get_close_success_count(guard)),
|
|
|
+ tor_lround(guard->circ_attempts),
|
|
|
+ tor_lround(guard->circ_successes),
|
|
|
+ tor_lround(guard->unusable_circuits),
|
|
|
+ tor_lround(guard->collapsed_circuits),
|
|
|
+ tor_lround(guard->timeouts),
|
|
|
+ tor_lround(circ_times.close_ms/1000));
|
|
|
+ guard->path_bias_disabled = 1;
|
|
|
+ guard->bad_since = approx_time();
|
|
|
+ return -1;
|
|
|
+ }
|
|
|
+ } else if (!guard->path_bias_extreme) {
|
|
|
+ guard->path_bias_extreme = 1;
|
|
|
+ log_warn(LD_CIRC,
|
|
|
+ "Your Guard %s=%s is failing to carry an extremely large "
|
|
|
+ "amount of streams on its circuits. "
|
|
|
+ "This could indicate a route manipulation attack, network "
|
|
|
+ "overload, bad local network connectivity, or a bug. "
|
|
|
+ "Use counts are %ld/%ld. Success counts are %ld/%ld. "
|
|
|
+ "%ld circuits completed, %ld were unusable, %ld collapsed, "
|
|
|
+ "and %ld timed out. "
|
|
|
+ "For reference, your timeout cutoff is %ld seconds.",
|
|
|
+ guard->nickname, hex_str(guard->identity, DIGEST_LEN),
|
|
|
+ tor_lround(pathbias_get_use_success_count(guard)),
|
|
|
+ tor_lround(guard->use_attempts),
|
|
|
+ tor_lround(pathbias_get_close_success_count(guard)),
|
|
|
+ tor_lround(guard->circ_attempts),
|
|
|
+ tor_lround(guard->circ_successes),
|
|
|
+ tor_lround(guard->unusable_circuits),
|
|
|
+ tor_lround(guard->collapsed_circuits),
|
|
|
+ tor_lround(guard->timeouts),
|
|
|
+ tor_lround(circ_times.close_ms/1000));
|
|
|
+ }
|
|
|
+ } else if (pathbias_get_use_success_count(guard)/guard->use_attempts
|
|
|
+ < pathbias_get_notice_use_rate(options)) {
|
|
|
+ if (!guard->path_bias_noticed) {
|
|
|
+ guard->path_bias_noticed = 1;
|
|
|
+ log_notice(LD_CIRC,
|
|
|
+ "Your Guard %s=%s is failing to carry more streams on its "
|
|
|
+ "circuits than usual. "
|
|
|
+ "Most likely this means the Tor network is overloaded "
|
|
|
+ "or your network connection is poor. "
|
|
|
+ "Use counts are %ld/%ld. Success counts are %ld/%ld. "
|
|
|
+ "%ld circuits completed, %ld were unusable, %ld collapsed, "
|
|
|
+ "and %ld timed out. "
|
|
|
+ "For reference, your timeout cutoff is %ld seconds.",
|
|
|
+ guard->nickname, hex_str(guard->identity, DIGEST_LEN),
|
|
|
+ tor_lround(pathbias_get_use_success_count(guard)),
|
|
|
+ tor_lround(guard->use_attempts),
|
|
|
+ tor_lround(pathbias_get_close_success_count(guard)),
|
|
|
+ tor_lround(guard->circ_attempts),
|
|
|
+ tor_lround(guard->circ_successes),
|
|
|
+ tor_lround(guard->unusable_circuits),
|
|
|
+ tor_lround(guard->collapsed_circuits),
|
|
|
+ tor_lround(guard->timeouts),
|
|
|
+ tor_lround(circ_times.close_ms/1000));
|
|
|
+ }
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ /* If we get a ton of circuits, just scale everything down */
|
|
|
+ if (guard->use_attempts > pathbias_get_scale_use_threshold(options)) {
|
|
|
+ const int scale_factor = pathbias_get_scale_factor(options);
|
|
|
+ const int mult_factor = pathbias_get_mult_factor(options);
|
|
|
+ log_info(LD_CIRC,
|
|
|
+ "Scaling pathbias use counts to (%f/%f)*(%d/%d) for guard %s=%s",
|
|
|
+ guard->use_successes, guard->use_attempts,
|
|
|
+ mult_factor, scale_factor, guard->nickname,
|
|
|
+ hex_str(guard->identity, DIGEST_LEN));
|
|
|
+
|
|
|
+ guard->use_attempts *= mult_factor;
|
|
|
+ guard->use_successes *= mult_factor;
|
|
|
+
|
|
|
+ guard->use_attempts /= scale_factor;
|
|
|
+ guard->use_successes /= scale_factor;
|
|
|
+ }
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * Check the path bias circuit close status rates against our consensus
|
|
|
+ * parameter limits.
|
|
|
+ *
|
|
|
+ * Emits a log message if the use success rates are too low.
|
|
|
+ *
|
|
|
+ * If pathbias_get_dropguards() is set, we also disable the use of
|
|
|
+ * very failure prone guards.
|
|
|
+ *
|
|
|
+ * Returns -1 if we decided to disable the guard, 0 otherwise.
|
|
|
+ */
|
|
|
+static int
|
|
|
+pathbias_check_close_rate(entry_guard_t *guard)
|
|
|
+{
|
|
|
+ const or_options_t *options = get_options();
|
|
|
|
|
|
if (guard->circ_attempts > pathbias_get_min_circs(options)) {
|
|
|
/* Note: We rely on the < comparison here to allow us to set a 0
|
|
|
* rate and disable the feature entirely. If refactoring, don't
|
|
|
* change to <= */
|
|
|
- if (pathbias_get_success_count(guard)/guard->circ_attempts
|
|
|
+ if (pathbias_get_close_success_count(guard)/guard->circ_attempts
|
|
|
< pathbias_get_extreme_rate(options)) {
|
|
|
/* Dropping is currently disabled by default. */
|
|
|
if (pathbias_get_dropguards(options)) {
|
|
|
if (!guard->path_bias_disabled) {
|
|
|
log_warn(LD_CIRC,
|
|
|
- "Your Guard %s=%s is failing an extremely large amount of "
|
|
|
- "circuits. To avoid potential route manipulation attacks, "
|
|
|
- "Tor has disabled use of this guard. "
|
|
|
- "Success counts are %ld/%ld. %ld circuits completed, %ld "
|
|
|
- "were unusable, %ld collapsed, and %ld timed out. For "
|
|
|
- "reference, your timeout cutoff is %ld seconds.",
|
|
|
+ "Your Guard %s=%s is failing an extremely large "
|
|
|
+ "amount of circuits. "
|
|
|
+ "To avoid potential route manipluation attacks, Tor has "
|
|
|
+ "disabled use of this guard. "
|
|
|
+ "Success counts are %ld/%ld. Use counts are %ld/%ld. "
|
|
|
+ "%ld circuits completed, %ld were unusable, %ld collapsed, "
|
|
|
+ "and %ld timed out. "
|
|
|
+ "For reference, your timeout cutoff is %ld seconds.",
|
|
|
guard->nickname, hex_str(guard->identity, DIGEST_LEN),
|
|
|
- tor_lround(pathbias_get_closed_count(guard)),
|
|
|
+ tor_lround(pathbias_get_close_success_count(guard)),
|
|
|
tor_lround(guard->circ_attempts),
|
|
|
+ tor_lround(pathbias_get_use_success_count(guard)),
|
|
|
+ tor_lround(guard->use_attempts),
|
|
|
tor_lround(guard->circ_successes),
|
|
|
tor_lround(guard->unusable_circuits),
|
|
|
tor_lround(guard->collapsed_circuits),
|
|
@@ -1972,60 +2322,72 @@ entry_guard_inc_circ_attempt_count(entry_guard_t *guard)
|
|
|
} else if (!guard->path_bias_extreme) {
|
|
|
guard->path_bias_extreme = 1;
|
|
|
log_warn(LD_CIRC,
|
|
|
- "Your Guard %s=%s is failing an extremely large amount of "
|
|
|
- "circuits. This could indicate a route manipulation attack, "
|
|
|
+ "Your Guard %s=%s is failing an extremely large "
|
|
|
+ "amount of circuits. "
|
|
|
+ "This could indicate a route manipulation attack, "
|
|
|
"extreme network overload, or a bug. "
|
|
|
- "Success counts are %ld/%ld. %ld circuits completed, %ld "
|
|
|
- "were unusable, %ld collapsed, and %ld timed out. For "
|
|
|
- "reference, your timeout cutoff is %ld seconds.",
|
|
|
+ "Success counts are %ld/%ld. Use counts are %ld/%ld. "
|
|
|
+ "%ld circuits completed, %ld were unusable, %ld collapsed, "
|
|
|
+ "and %ld timed out. "
|
|
|
+ "For reference, your timeout cutoff is %ld seconds.",
|
|
|
guard->nickname, hex_str(guard->identity, DIGEST_LEN),
|
|
|
- tor_lround(pathbias_get_closed_count(guard)),
|
|
|
+ tor_lround(pathbias_get_close_success_count(guard)),
|
|
|
tor_lround(guard->circ_attempts),
|
|
|
+ tor_lround(pathbias_get_use_success_count(guard)),
|
|
|
+ tor_lround(guard->use_attempts),
|
|
|
tor_lround(guard->circ_successes),
|
|
|
tor_lround(guard->unusable_circuits),
|
|
|
tor_lround(guard->collapsed_circuits),
|
|
|
tor_lround(guard->timeouts),
|
|
|
tor_lround(circ_times.close_ms/1000));
|
|
|
}
|
|
|
- } else if (pathbias_get_success_count(guard)/((double)guard->circ_attempts)
|
|
|
- < pathbias_get_warn_rate(options)) {
|
|
|
+ } else if (pathbias_get_close_success_count(guard)/guard->circ_attempts
|
|
|
+ < pathbias_get_warn_rate(options)) {
|
|
|
if (!guard->path_bias_warned) {
|
|
|
guard->path_bias_warned = 1;
|
|
|
log_warn(LD_CIRC,
|
|
|
- "Your Guard %s=%s is failing a very large amount of "
|
|
|
- "circuits. Most likely this means the Tor network is "
|
|
|
+ "Your Guard %s=%s is failing a very large "
|
|
|
+ "amount of circuits. "
|
|
|
+ "Most likely this means the Tor network is "
|
|
|
"overloaded, but it could also mean an attack against "
|
|
|
- "you or potentially the guard itself. "
|
|
|
- "Success counts are %ld/%ld. %ld circuits completed, %ld "
|
|
|
- "were unusable, %ld collapsed, and %ld timed out. For "
|
|
|
- "reference, your timeout cutoff is %ld seconds.",
|
|
|
+ "you or the potentially the guard itself. "
|
|
|
+ "Success counts are %ld/%ld. Use counts are %ld/%ld. "
|
|
|
+ "%ld circuits completed, %ld were unusable, %ld collapsed, "
|
|
|
+ "and %ld timed out. "
|
|
|
+ "For reference, your timeout cutoff is %ld seconds.",
|
|
|
guard->nickname, hex_str(guard->identity, DIGEST_LEN),
|
|
|
- tor_lround(pathbias_get_closed_count(guard)),
|
|
|
+ tor_lround(pathbias_get_close_success_count(guard)),
|
|
|
tor_lround(guard->circ_attempts),
|
|
|
+ tor_lround(pathbias_get_use_success_count(guard)),
|
|
|
+ tor_lround(guard->use_attempts),
|
|
|
tor_lround(guard->circ_successes),
|
|
|
tor_lround(guard->unusable_circuits),
|
|
|
tor_lround(guard->collapsed_circuits),
|
|
|
tor_lround(guard->timeouts),
|
|
|
tor_lround(circ_times.close_ms/1000));
|
|
|
}
|
|
|
- } else if (pathbias_get_success_count(guard)/((double)guard->circ_attempts)
|
|
|
+ } else if (pathbias_get_close_success_count(guard)/guard->circ_attempts
|
|
|
< pathbias_get_notice_rate(options)) {
|
|
|
if (!guard->path_bias_noticed) {
|
|
|
guard->path_bias_noticed = 1;
|
|
|
log_notice(LD_CIRC,
|
|
|
- "Your Guard %s=%s is failing more circuits than usual. "
|
|
|
- "Most likely this means the Tor network is overloaded. "
|
|
|
- "Success counts are %ld/%ld. %ld circuits completed, %ld "
|
|
|
- "were unusable, %ld collapsed, and %ld timed out. For "
|
|
|
- "reference, your timeout cutoff is %ld seconds.",
|
|
|
- guard->nickname, hex_str(guard->identity, DIGEST_LEN),
|
|
|
- tor_lround(pathbias_get_closed_count(guard)),
|
|
|
- tor_lround(guard->circ_attempts),
|
|
|
- tor_lround(guard->circ_successes),
|
|
|
- tor_lround(guard->unusable_circuits),
|
|
|
- tor_lround(guard->collapsed_circuits),
|
|
|
- tor_lround(guard->timeouts),
|
|
|
- tor_lround(circ_times.close_ms/1000));
|
|
|
+ "Your Guard %s=%s is failing more circuits than "
|
|
|
+ "usual. "
|
|
|
+ "Most likely this means the Tor network is overloaded. "
|
|
|
+ "Success counts are %ld/%ld. Use counts are %ld/%ld. "
|
|
|
+ "%ld circuits completed, %ld were unusable, %ld collapsed, "
|
|
|
+ "and %ld timed out. "
|
|
|
+ "For reference, your timeout cutoff is %ld seconds.",
|
|
|
+ guard->nickname, hex_str(guard->identity, DIGEST_LEN),
|
|
|
+ tor_lround(pathbias_get_close_success_count(guard)),
|
|
|
+ tor_lround(guard->circ_attempts),
|
|
|
+ tor_lround(pathbias_get_use_success_count(guard)),
|
|
|
+ tor_lround(guard->use_attempts),
|
|
|
+ tor_lround(guard->circ_successes),
|
|
|
+ tor_lround(guard->unusable_circuits),
|
|
|
+ tor_lround(guard->collapsed_circuits),
|
|
|
+ tor_lround(guard->timeouts),
|
|
|
+ tor_lround(circ_times.close_ms/1000));
|
|
|
}
|
|
|
}
|
|
|
}
|
|
@@ -2054,7 +2416,24 @@ entry_guard_inc_circ_attempt_count(entry_guard_t *guard)
|
|
|
guard->collapsed_circuits /= scale_factor;
|
|
|
guard->unusable_circuits /= scale_factor;
|
|
|
}
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+/** Increment the number of times we successfully extended a circuit to
|
|
|
+ * 'guard', first checking if the failure rate is high enough that we should
|
|
|
+ * eliminate the guard. Return -1 if the guard looks no good; return 0 if the
|
|
|
+ * guard looks fine. */
|
|
|
+static int
|
|
|
+entry_guard_inc_circ_attempt_count(entry_guard_t *guard)
|
|
|
+{
|
|
|
+ entry_guards_changed();
|
|
|
+
|
|
|
+ if (pathbias_check_close_rate(guard) < 0)
|
|
|
+ return -1;
|
|
|
+
|
|
|
guard->circ_attempts++;
|
|
|
+
|
|
|
log_info(LD_CIRC, "Got success count %f/%f for guard %s=%s",
|
|
|
guard->circ_successes, guard->circ_attempts, guard->nickname,
|
|
|
hex_str(guard->identity, DIGEST_LEN));
|
|
@@ -2078,7 +2457,7 @@ circuit_finish_handshake(origin_circuit_t *circ,
|
|
|
crypt_path_t *hop;
|
|
|
int rv;
|
|
|
|
|
|
- if ((rv = pathbias_count_circ_attempt(circ)) < 0)
|
|
|
+ if ((rv = pathbias_count_build_attempt(circ)) < 0)
|
|
|
return rv;
|
|
|
|
|
|
if (circ->cpath->state == CPATH_STATE_AWAITING_KEYS) {
|