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Merge branch 'bug7802' of ssh://git-rw.torproject.org/mikeperry/tor

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This commit is contained in:
Andrea Shepard 2013-01-28 16:16:45 -08:00
commit 123daffb60
13 changed files with 695 additions and 155 deletions
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11
changes/bug7802 Normal file
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@ -0,0 +1,11 @@
o Minor features:
- Path Use Bias: Perform separate accounting for successful circuit use.
Separate statistics on stream attempt versus success rates are kept
for each guard. Configurable thresholds are provided to determine
when to emit log messages or disable use of guards that fail too
many stream attempts.
o Minor bugfixes:
- Remove a source of rounding error during path bias count scaling.
- Don't count cannibalized circuits as used for path bias until we
actually try to use them.
- Fix circuit_package_relay_cell warning message about n_chan==NULL.

31
doc/tor.1.txt
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@ -1242,16 +1242,11 @@ The following options are useful only for clients (that is, if
**PathBiasMultFactor** __NUM__ +
**PathBiasScaleFactor** __NUM__ +
**PathBiasUseCloseCounts** __NUM__::
**PathBiasScaleFactor** __NUM__::
These options override the default behavior of Tor's (**currently
experimental**) path bias detection algorithm. To try to find broken or
misbehaving guard nodes, Tor looks for nodes where more than a certain
fraction of circuits through that guard fail to get built. If
PathBiasUseCloseCounts is set to 1 (the default), usage-based accounting is
performed, and circuits that fail to carry streams are also counted as
failures. +
fraction of circuits through that guard fail to get built.
+
The PathBiasCircThreshold option controls how many circuits we need to build
through a guard before we make these checks. The PathBiasNoticeRate,
@ -1270,6 +1265,28 @@ The following options are useful only for clients (that is, if
If no defaults are available there, these options default to 150, .70,
.50, .30, 0, 300, 1, and 2 respectively.
**PathBiasUseThreshold** __NUM__ +
**PathBiasNoticeUseRate** __NUM__ +
**PathBiasExtremeUseRate** __NUM__ +
**PathBiasScaleUseThreshold** __NUM__::
Similar to the above options, these options override the default behavior
of Tor's (**currently experimental**) path use bias detection algorithm.
+
Where as the path bias parameters govern thresholds for successfully
building circuits, these four path use bias parameters govern thresholds
only for circuit usage. Circuits which receive no stream usage
are not counted by this detection algorithm. A used circuit is considered
successful if it is capable of carrying streams or otherwise receiving
well-formed responses to RELAY cells.
+
By default, or if a negative value is provided for one of these options,
Tor uses reasonable defaults from the networkstatus consensus document.
If no defaults are available there, these options default to 20, .90,
.70, and 100, respectively.
**ClientUseIPv6** **0**|**1**::
If this option is set to 1, Tor might connect to entry nodes over
IPv6. Note that clients configured with an IPv6 address in a

626
src/or/circuitbuild.c
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@ -67,7 +67,9 @@ static int entry_guard_inc_circ_attempt_count(entry_guard_t *guard);
static void pathbias_count_build_success(origin_circuit_t *circ);
static void pathbias_count_successful_close(origin_circuit_t *circ);
static void pathbias_count_collapse(origin_circuit_t *circ);
static void pathbias_count_unusable(origin_circuit_t *circ);
static void pathbias_count_use_failed(origin_circuit_t *circ);
static int pathbias_check_use_rate(entry_guard_t *guard);
static int pathbias_check_close_rate(entry_guard_t *guard);
/** This function tries to get a channel to the specified endpoint,
* and then calls command_setup_channel() to give it the right
@ -821,9 +823,6 @@ circuit_send_next_onion_skin(origin_circuit_t *circ)
/* We're done with measurement circuits here. Just close them */
if (circ->base_.purpose == CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT) {
/* If a measurement circ ever gets back to us, consider it
* succeeded for path bias */
circ->path_state = PATH_STATE_USE_SUCCEEDED;
circuit_mark_for_close(TO_CIRCUIT(circ), END_CIRC_REASON_FINISHED);
}
return 0;
@ -1210,19 +1209,65 @@ pathbias_get_mult_factor(const or_options_t *options)
pathbias_get_scale_factor(options));
}
/** The minimum number of circuit usage attempts before we start
* thinking about warning about path use bias and dropping guards */
static int
pathbias_get_min_use(const or_options_t *options)
{
#define DFLT_PATH_BIAS_MIN_USE 20
if (options->PathBiasUseThreshold >= 3)
return options->PathBiasUseThreshold;
else
return networkstatus_get_param(NULL, "pb_minuse",
DFLT_PATH_BIAS_MIN_USE,
3, INT32_MAX);
}
/** The circuit use success rate below which we issue a notice */
static double
pathbias_get_notice_use_rate(const or_options_t *options)
{
#define DFLT_PATH_BIAS_NOTICE_USE_PCT 90
if (options->PathBiasNoticeUseRate >= 0.0)
return options->PathBiasNoticeUseRate;
else
return networkstatus_get_param(NULL, "pb_noticeusepct",
DFLT_PATH_BIAS_NOTICE_USE_PCT,
0, 100)/100.0;
}
/**
* If this parameter is set to a true value (default), we use the
* successful_circuits_closed. Otherwise, we use the success_count.
* The extreme use rate is the rate at which we would drop the guard,
* if pb_dropguard is also set. Otherwise we just warn.
*/
double
pathbias_get_extreme_use_rate(const or_options_t *options)
{
#define DFLT_PATH_BIAS_EXTREME_USE_PCT 70
if (options->PathBiasExtremeUseRate >= 0.0)
return options->PathBiasExtremeUseRate;
else
return networkstatus_get_param(NULL, "pb_extremeusepct",
DFLT_PATH_BIAS_EXTREME_USE_PCT,
0, 100)/100.0;
}
/**
* This is the number of circuits at which we scale our
* use counts by mult_factor/scale_factor. Note, this count is
* not exact, as we only perform the scaling in the event
* of no integer truncation.
*/
static int
pathbias_use_close_counts(const or_options_t *options)
pathbias_get_scale_use_threshold(const or_options_t *options)
{
#define DFLT_PATH_BIAS_USE_CLOSE_COUNTS 1
if (options->PathBiasUseCloseCounts >= 0)
return options->PathBiasUseCloseCounts;
#define DFLT_PATH_BIAS_SCALE_USE_THRESHOLD 100
if (options->PathBiasScaleUseThreshold >= 10)
return options->PathBiasScaleUseThreshold;
else
return networkstatus_get_param(NULL, "pb_useclosecounts",
DFLT_PATH_BIAS_USE_CLOSE_COUNTS, 0, 1);
return networkstatus_get_param(NULL, "pb_scaleuse",
DFLT_PATH_BIAS_SCALE_USE_THRESHOLD,
10, INT32_MAX);
}
/**
@ -1238,10 +1283,14 @@ pathbias_state_to_string(path_state_t state)
return "build attempted";
case PATH_STATE_BUILD_SUCCEEDED:
return "build succeeded";
case PATH_STATE_USE_ATTEMPTED:
return "use attempted";
case PATH_STATE_USE_SUCCEEDED:
return "use succeeded";
case PATH_STATE_USE_FAILED:
return "use failed";
case PATH_STATE_ALREADY_COUNTED:
return "already counted";
}
return "unknown";
@ -1338,7 +1387,7 @@ pathbias_should_count(origin_circuit_t *circ)
* Also check for several potential error cases for bug #6475.
*/
static int
pathbias_count_circ_attempt(origin_circuit_t *circ)
pathbias_count_build_attempt(origin_circuit_t *circ)
{
#define CIRC_ATTEMPT_NOTICE_INTERVAL (600)
static ratelim_t circ_attempt_notice_limit =
@ -1504,6 +1553,130 @@ pathbias_count_build_success(origin_circuit_t *circ)
}
}
/**
* Record an attempt to use a circuit. Changes the circuit's
* path state and update its guard's usage counter.
*
* Used for path bias usage accounting.
*/
void
pathbias_count_use_attempt(origin_circuit_t *circ)
{
entry_guard_t *guard;
if (!pathbias_should_count(circ)) {
return;
}
if (circ->path_state < PATH_STATE_BUILD_SUCCEEDED) {
log_notice(LD_BUG,
"Used circuit is in strange path state %s. "
"Circuit is a %s currently %s.",
pathbias_state_to_string(circ->path_state),
circuit_purpose_to_string(circ->base_.purpose),
circuit_state_to_string(circ->base_.state));
} else if (circ->path_state < PATH_STATE_USE_ATTEMPTED) {
guard = entry_guard_get_by_id_digest(
circ->cpath->extend_info->identity_digest);
if (guard) {
pathbias_check_use_rate(guard);
guard->use_attempts++;
log_debug(LD_CIRC,
"Marked circuit %d (%f/%f) as used for guard %s=%s.",
circ->global_identifier,
guard->use_successes, guard->use_attempts,
guard->nickname, hex_str(guard->identity, DIGEST_LEN));
}
circ->path_state = PATH_STATE_USE_ATTEMPTED;
} else {
/* Harmless but educational log message */
log_info(LD_CIRC,
"Used circuit %d is already in path state %s. "
"Circuit is a %s currently %s.",
circ->global_identifier,
pathbias_state_to_string(circ->path_state),
circuit_purpose_to_string(circ->base_.purpose),
circuit_state_to_string(circ->base_.state));
}
return;
}
/**
* Check the circuit's path stat is appropriate and it as successfully
* used.
*
* We don't actually increment the guard's counters until
* pathbias_check_close().
*
* Used for path bias usage accounting.
*/
void
pathbias_mark_use_success(origin_circuit_t *circ)
{
if (!pathbias_should_count(circ)) {
return;
}
if (circ->path_state < PATH_STATE_USE_ATTEMPTED) {
log_notice(LD_BUG,
"Used circuit %d is in strange path state %s. "
"Circuit is a %s currently %s.",
circ->global_identifier,
pathbias_state_to_string(circ->path_state),
circuit_purpose_to_string(circ->base_.purpose),
circuit_state_to_string(circ->base_.state));
pathbias_count_use_attempt(circ);
}
/* We don't do any accounting at the guard until actual circuit close */
circ->path_state = PATH_STATE_USE_SUCCEEDED;
return;
}
/**
* Actually count a circuit success towards a guard's usage counters
* if the path state is appropriate.
*/
static void
pathbias_count_use_success(origin_circuit_t *circ)
{
entry_guard_t *guard;
if (!pathbias_should_count(circ)) {
return;
}
if (circ->path_state != PATH_STATE_USE_SUCCEEDED) {
log_notice(LD_BUG,
"Successfully used circuit %d is in strange path state %s. "
"Circuit is a %s currently %s.",
circ->global_identifier,
pathbias_state_to_string(circ->path_state),
circuit_purpose_to_string(circ->base_.purpose),
circuit_state_to_string(circ->base_.state));
} else {
guard = entry_guard_get_by_id_digest(
circ->cpath->extend_info->identity_digest);
if (guard) {
guard->use_successes++;
log_debug(LD_CIRC,
"Marked circuit %d (%f/%f) as used successfully for guard "
"%s=%s.",
circ->global_identifier, guard->use_successes,
guard->use_attempts, guard->nickname,
hex_str(guard->identity, DIGEST_LEN));
}
}
return;
}
/**
* Send a probe down a circuit that the client attempted to use,
* but for which the stream timed out/failed. The probe is a
@ -1554,6 +1727,16 @@ pathbias_send_usable_probe(circuit_t *circ)
return -1;
}
/* Can't probe if the channel isn't open */
if (circ->n_chan == NULL ||
(circ->n_chan->state != CHANNEL_STATE_OPEN
&& circ->n_chan->state != CHANNEL_STATE_MAINT)) {
log_info(LD_CIRC,
"Skipping pathbias probe for circuit %d: Channel is not open.",
ocirc->global_identifier);
return -1;
}
circuit_change_purpose(circ, CIRCUIT_PURPOSE_PATH_BIAS_TESTING);
/* Update timestamp for when circuit_expire_building() should kill us */
@ -1648,7 +1831,7 @@ pathbias_check_probe_response(circuit_t *circ, const cell_t *cell)
/* Check nonce */
if (ipv4_host == ocirc->pathbias_probe_nonce) {
ocirc->path_state = PATH_STATE_USE_SUCCEEDED;
pathbias_mark_use_success(ocirc);
circuit_mark_for_close(circ, END_CIRC_REASON_FINISHED);
log_info(LD_CIRC,
"Got valid path bias probe back for circ %d, stream %d.",
@ -1691,24 +1874,11 @@ pathbias_check_close(origin_circuit_t *ocirc, int reason)
return 0;
}
if (ocirc->path_state == PATH_STATE_BUILD_SUCCEEDED) {
if (circ->timestamp_dirty) {
if (pathbias_send_usable_probe(circ) == 0)
return -1;
else
pathbias_count_unusable(ocirc);
/* Any circuit where there were attempted streams but no successful
* streams could be bias */
log_info(LD_CIRC,
"Circuit %d closed without successful use for reason %d. "
"Circuit purpose %d currently %d,%s. Len %d.",
ocirc->global_identifier,
reason, circ->purpose, ocirc->has_opened,
circuit_state_to_string(circ->state),
ocirc->build_state->desired_path_len);
} else {
switch (ocirc->path_state) {
/* If the circuit was closed after building, but before use, we need
* to ensure we were the ones who tried to close it (and not a remote
* actor). */
case PATH_STATE_BUILD_SUCCEEDED:
if (reason & END_CIRC_REASON_FLAG_REMOTE) {
/* Remote circ close reasons on an unused circuit all could be bias */
log_info(LD_CIRC,
@ -1739,11 +1909,41 @@ pathbias_check_close(origin_circuit_t *ocirc, int reason)
} else {
pathbias_count_successful_close(ocirc);
}
}
} else if (ocirc->path_state == PATH_STATE_USE_SUCCEEDED) {
pathbias_count_successful_close(ocirc);
break;
/* If we tried to use a circuit but failed, we should probe it to ensure
* it has not been tampered with. */
case PATH_STATE_USE_ATTEMPTED:
/* XXX: Only probe and/or count failure if the network is live?
* What about clock jumps/suspends? */
if (pathbias_send_usable_probe(circ) == 0)
return -1;
else
pathbias_count_use_failed(ocirc);
/* Any circuit where there were attempted streams but no successful
* streams could be bias */
log_info(LD_CIRC,
"Circuit %d closed without successful use for reason %d. "
"Circuit purpose %d currently %d,%s. Len %d.",
ocirc->global_identifier,
reason, circ->purpose, ocirc->has_opened,
circuit_state_to_string(circ->state),
ocirc->build_state->desired_path_len);
break;
case PATH_STATE_USE_SUCCEEDED:
pathbias_count_successful_close(ocirc);
pathbias_count_use_success(ocirc);
break;
default:
// Other states are uninteresting. No stats to count.
break;
}
ocirc->path_state = PATH_STATE_ALREADY_COUNTED;
return 0;
}
@ -1792,6 +1992,7 @@ static void
pathbias_count_collapse(origin_circuit_t *circ)
{
entry_guard_t *guard = NULL;
if (!pathbias_should_count(circ)) {
return;
}
@ -1816,8 +2017,13 @@ pathbias_count_collapse(origin_circuit_t *circ)
}
}
/**
* Count a known failed circuit (because we could not probe it).
*
* This counter is informational.
*/
static void
pathbias_count_unusable(origin_circuit_t *circ)
pathbias_count_use_failed(origin_circuit_t *circ)
{
entry_guard_t *guard = NULL;
if (!pathbias_should_count(circ)) {
@ -1879,20 +2085,20 @@ pathbias_count_timeout(origin_circuit_t *circ)
}
/**
* Return the number of circuits counted as successfully closed for
* this guard.
*
* Also add in the currently open circuits to give them the benefit
* of the doubt.
* Helper function to count all of the currently opened circuits
* for a guard that are in a given path state range. The state
* range is inclusive on both ends.
*/
double
pathbias_get_closed_count(entry_guard_t *guard)
static int
pathbias_count_circs_in_states(entry_guard_t *guard,
path_state_t from,
path_state_t to)
{
circuit_t *circ;
circuit_t *circ = global_circuitlist;
int open_circuits = 0;
/* Count currently open circuits. Give them the benefit of the doubt. */
for (circ = global_circuitlist; circ; circ = circ->next) {
/* Count currently open circuits. Give them the benefit of the doubt */
for ( ; circ; circ = circ->next) {
origin_circuit_t *ocirc = NULL;
if (!CIRCUIT_IS_ORIGIN(circ) || /* didn't originate here */
circ->marked_for_close) /* already counted */
@ -1903,62 +2109,91 @@ pathbias_get_closed_count(entry_guard_t *guard)
if (!ocirc->cpath || !ocirc->cpath->extend_info)
continue;
if (ocirc->path_state >= PATH_STATE_BUILD_SUCCEEDED &&
if (ocirc->path_state >= from &&
ocirc->path_state <= to &&
pathbias_should_count(ocirc) &&
fast_memeq(guard->identity,
ocirc->cpath->extend_info->identity_digest,
DIGEST_LEN)) {
ocirc->cpath->extend_info->identity_digest,
DIGEST_LEN)) {
log_debug(LD_CIRC, "Found opened circuit %d in path_state %s",
ocirc->global_identifier,
pathbias_state_to_string(ocirc->path_state));
open_circuits++;
}
}
return guard->successful_circuits_closed + open_circuits;
return open_circuits;
}
/**
* This function checks the consensus parameters to decide
* if it should return guard->circ_successes or
* guard->successful_circuits_closed.
* Return the number of circuits counted as successfully closed for
* this guard.
*
* Also add in the currently open circuits to give them the benefit
* of the doubt.
*/
double
pathbias_get_success_count(entry_guard_t *guard)
pathbias_get_close_success_count(entry_guard_t *guard)
{
if (pathbias_use_close_counts(get_options())) {
return pathbias_get_closed_count(guard);
} else {
return guard->circ_successes;
}
return guard->successful_circuits_closed +
pathbias_count_circs_in_states(guard,
PATH_STATE_BUILD_SUCCEEDED,
PATH_STATE_USE_SUCCEEDED);
}
/** 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.
/**
* Return the number of circuits counted as successfully used
* this guard.
*
* Also add in the currently open circuits that we are attempting
* to use to give them the benefit of the doubt.
*/
double
pathbias_get_use_success_count(entry_guard_t *guard)
{
return guard->use_successes +
pathbias_count_circs_in_states(guard,
PATH_STATE_USE_ATTEMPTED,
PATH_STATE_USE_SUCCEEDED);
}
/**
* 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->circ_attempts > pathbias_get_min_circs(options)) {
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_success_count(guard)/guard->circ_attempts
< pathbias_get_extreme_rate(options)) {
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 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 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_closed_count(guard)),
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),
@ -1972,14 +2207,18 @@ 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, "
"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.",
"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_closed_count(guard)),
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),
@ -1987,45 +2226,175 @@ entry_guard_inc_circ_attempt_count(entry_guard_t *guard)
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_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);
int opened_attempts = pathbias_count_circs_in_states(guard,
PATH_STATE_USE_ATTEMPTED, PATH_STATE_USE_SUCCEEDED);
guard->use_attempts -= opened_attempts;
guard->use_attempts *= mult_factor;
guard->use_successes *= mult_factor;
guard->use_attempts /= scale_factor;
guard->use_successes /= scale_factor;
guard->use_attempts += opened_attempts;
log_info(LD_CIRC,
"Scaled pathbias use counts to %f/%f (%d open) for guard %s=%s",
guard->use_successes, guard->use_attempts, opened_attempts,
guard->nickname, hex_str(guard->identity, DIGEST_LEN));
}
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_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 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_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));
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 an extremely large "
"amount of circuits. "
"This could indicate a route manipulation attack, "
"extreme network overload, or a bug. "
"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));
}
} 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));
}
}
}
@ -2034,11 +2403,13 @@ entry_guard_inc_circ_attempt_count(entry_guard_t *guard)
if (guard->circ_attempts > pathbias_get_scale_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 counts to (%f/%f)*(%d/%d) for guard %s=%s",
guard->circ_successes, guard->circ_attempts,
mult_factor, scale_factor, guard->nickname,
hex_str(guard->identity, DIGEST_LEN));
int opened_attempts = pathbias_count_circs_in_states(guard,
PATH_STATE_BUILD_ATTEMPTED, PATH_STATE_BUILD_ATTEMPTED);
int opened_built = pathbias_count_circs_in_states(guard,
PATH_STATE_BUILD_SUCCEEDED,
PATH_STATE_USE_FAILED);
guard->circ_attempts -= opened_attempts;
guard->circ_successes -= opened_built;
guard->circ_attempts *= mult_factor;
guard->circ_successes *= mult_factor;
@ -2053,8 +2424,35 @@ entry_guard_inc_circ_attempt_count(entry_guard_t *guard)
guard->successful_circuits_closed /= scale_factor;
guard->collapsed_circuits /= scale_factor;
guard->unusable_circuits /= scale_factor;
guard->circ_attempts += opened_attempts;
guard->circ_successes += opened_built;
log_info(LD_CIRC,
"Scaled pathbias counts to (%f,%f)/%f (%d/%d open) for guard "
"%s=%s",
guard->circ_successes, guard->successful_circuits_closed,
guard->circ_attempts, opened_built, opened_attempts,
guard->nickname, hex_str(guard->identity, DIGEST_LEN));
}
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 +2476,7 @@ 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) {
@ -2761,9 +3159,7 @@ circuit_extend_to_new_exit(origin_circuit_t *circ, extend_info_t *exit)
return -1;
}
/* Set timestamp_dirty, so we can check it for path use bias */
if (!circ->base_.timestamp_dirty)
circ->base_.timestamp_dirty = time(NULL);
// XXX: Should cannibalized circuits be dirty or not? Not easy to say..
return 0;
}

3
src/or/circuitbuild.h
View File

@ -58,10 +58,13 @@ const char *build_state_get_exit_nickname(cpath_build_state_t *state);
const node_t *choose_good_entry_server(uint8_t purpose,
cpath_build_state_t *state);
double pathbias_get_extreme_rate(const or_options_t *options);
double pathbias_get_extreme_use_rate(const or_options_t *options);
int pathbias_get_dropguards(const or_options_t *options);
void pathbias_count_timeout(origin_circuit_t *circ);
int pathbias_check_close(origin_circuit_t *circ, int reason);
int pathbias_check_probe_response(circuit_t *circ, const cell_t *cell);
void pathbias_count_use_attempt(origin_circuit_t *circ);
void pathbias_mark_use_success(origin_circuit_t *circ);
#endif

30
src/or/circuituse.c
View File

@ -668,18 +668,6 @@ circuit_expire_building(void)
circuit_build_times_set_timeout(&circ_times);
}
}
if (TO_ORIGIN_CIRCUIT(victim)->has_opened &&
victim->purpose != CIRCUIT_PURPOSE_PATH_BIAS_TESTING) {
/* For path bias: we want to let these guys live for a while
* so we get a chance to test them. */
log_info(LD_CIRC,
"Allowing cannibalized circuit %d time to finish building "
"as a pathbias testing circ.",
TO_ORIGIN_CIRCUIT(victim)->global_identifier);
circuit_change_purpose(victim, CIRCUIT_PURPOSE_PATH_BIAS_TESTING);
continue; /* It now should have a longer timeout next time */
}
}
/* If this is a hidden service client circuit which is far enough
@ -1090,7 +1078,10 @@ circuit_expire_old_circuits_clientside(void)
"purpose %d)",
circ->n_circ_id, (long)(now.tv_sec - circ->timestamp_dirty),
circ->purpose);
circuit_mark_for_close(circ, END_CIRC_REASON_FINISHED);
/* Don't do this magic for testing circuits. Their death is governed
* by circuit_expire_building */
if (circ->purpose != CIRCUIT_PURPOSE_PATH_BIAS_TESTING)
circuit_mark_for_close(circ, END_CIRC_REASON_FINISHED);
} else if (!circ->timestamp_dirty && circ->state == CIRCUIT_STATE_OPEN) {
if (timercmp(&circ->timestamp_began, &cutoff, <)) {
if (circ->purpose == CIRCUIT_PURPOSE_C_GENERAL ||
@ -1517,7 +1508,7 @@ circuit_launch_by_extend_info(uint8_t purpose,
* If we decide to probe the initial portion of these circs,
* (up to the adversaries final hop), we need to remove this.
*/
circ->path_state = PATH_STATE_USE_SUCCEEDED;
/* This must be called before the purpose change */
pathbias_check_close(circ, END_CIRC_REASON_FINISHED);
}
@ -2037,6 +2028,8 @@ connection_ap_handshake_attach_chosen_circuit(entry_connection_t *conn,
if (!circ->base_.timestamp_dirty)
circ->base_.timestamp_dirty = time(NULL);
pathbias_count_use_attempt(circ);
link_apconn_to_circ(conn, circ, cpath);
tor_assert(conn->socks_request);
if (conn->socks_request->command == SOCKS_COMMAND_CONNECT) {
@ -2163,6 +2156,11 @@ connection_ap_handshake_attach_circuit(entry_connection_t *conn)
* feasibility, at this point.
*/
rendcirc->base_.timestamp_dirty = time(NULL);
/* We've also attempted to use them. If they fail, we need to
* probe them for path bias */
pathbias_count_use_attempt(rendcirc);
link_apconn_to_circ(conn, rendcirc, NULL);
if (connection_ap_handshake_send_begin(conn) < 0)
return 0; /* already marked, let them fade away */
@ -2214,6 +2212,10 @@ connection_ap_handshake_attach_circuit(entry_connection_t *conn)
case 0: /* success */
rendcirc->base_.timestamp_dirty = time(NULL);
introcirc->base_.timestamp_dirty = time(NULL);
pathbias_count_use_attempt(introcirc);
pathbias_count_use_attempt(rendcirc);
assert_circuit_ok(TO_CIRCUIT(rendcirc));
assert_circuit_ok(TO_CIRCUIT(introcirc));
return 0;

7
src/or/config.c
View File

@ -324,7 +324,12 @@ static config_var_t option_vars_[] = {
V(PathBiasScaleFactor, INT, "-1"),
V(PathBiasMultFactor, INT, "-1"),
V(PathBiasDropGuards, AUTOBOOL, "0"),
V(PathBiasUseCloseCounts, AUTOBOOL, "1"),
OBSOLETE("PathBiasUseCloseCounts"),
V(PathBiasUseThreshold, INT, "-1"),
V(PathBiasNoticeUseRate, DOUBLE, "-1"),
V(PathBiasExtremeUseRate, DOUBLE, "-1"),
V(PathBiasScaleUseThreshold, INT, "-1"),
OBSOLETE("PathlenCoinWeight"),
V(PerConnBWBurst, MEMUNIT, "0"),

28
src/or/connection_edge.c
View File

@ -37,6 +37,7 @@
#include "router.h"
#include "routerlist.h"
#include "routerset.h"
#include "circuitbuild.h"
#ifdef HAVE_LINUX_TYPES_H
#include <linux/types.h>
@ -636,6 +637,16 @@ connection_ap_expire_beginning(void)
}
if (circ->purpose == CIRCUIT_PURPOSE_C_REND_JOINED) {
if (seconds_idle >= options->SocksTimeout) {
/* Path bias: We need to probe the circuit to ensure validity.
* Roll its state back if it succeeded so that we do so upon close. */
if (TO_ORIGIN_CIRCUIT(circ)->path_state == PATH_STATE_USE_SUCCEEDED) {
log_info(LD_CIRC,
"Rolling back pathbias use state to 'attempted' for timed "
"out rend circ %d",
TO_ORIGIN_CIRCUIT(circ)->global_identifier);
TO_ORIGIN_CIRCUIT(circ)->path_state = PATH_STATE_USE_ATTEMPTED;
}
log_fn(severity, LD_REND,
"Rend stream is %d seconds late. Giving up on address"
" '%s.onion'.",
@ -805,6 +816,15 @@ connection_ap_detach_retriable(entry_connection_t *conn,
control_event_stream_status(conn, STREAM_EVENT_FAILED_RETRIABLE, reason);
ENTRY_TO_CONN(conn)->timestamp_lastread = time(NULL);
/* Path bias: We need to probe the circuit to ensure validity.
* Roll its state back if it succeeded so that we do so upon close. */
if (circ->path_state == PATH_STATE_USE_SUCCEEDED) {
log_info(LD_CIRC,
"Rolling back pathbias use state to 'attempted' for detached "
"circuit %d", circ->global_identifier);
circ->path_state = PATH_STATE_USE_ATTEMPTED;
}
if (conn->pending_optimistic_data) {
generic_buffer_set_to_copy(&conn->sending_optimistic_data,
conn->pending_optimistic_data);
@ -2205,8 +2225,10 @@ connection_ap_handshake_socks_reply(entry_connection_t *conn, char *reply,
U64_PRINTF_ARG(ENTRY_TO_CONN(conn)->global_identifier),
endreason);
} else {
TO_ORIGIN_CIRCUIT(conn->edge_.on_circuit)->path_state
= PATH_STATE_USE_SUCCEEDED;
// XXX: Hrmm. It looks like optimistic data can't go through this
// codepath, but someone should probably test it and make sure.
// We don't want to mark optimistically opened streams as successful.
pathbias_mark_use_success(TO_ORIGIN_CIRCUIT(conn->edge_.on_circuit));
}
}
@ -2480,7 +2502,7 @@ connection_exit_begin_conn(cell_t *cell, circuit_t *circ)
connection_exit_connect(n_stream);
/* For path bias: This circuit was used successfully */
origin_circ->path_state = PATH_STATE_USE_SUCCEEDED;
pathbias_mark_use_success(origin_circ);
tor_free(address);
return 0;

48
src/or/entrynodes.c
View File

@ -1098,6 +1098,40 @@ entry_guards_parse_state(or_state_t *state, int set, char **msg)
continue;
}
digestmap_set(added_by, d, tor_strdup(line->value+HEX_DIGEST_LEN+1));
} else if (!strcasecmp(line->key, "EntryGuardPathUseBias")) {
const or_options_t *options = get_options();
double use_cnt, success_cnt;
if (!node) {
*msg = tor_strdup("Unable to parse entry nodes: "
"EntryGuardPathUseBias without EntryGuard");
break;
}
if (tor_sscanf(line->value, "%lf %lf",
&use_cnt, &success_cnt) != 2) {
log_info(LD_GENERAL, "Malformed path use bias line for node %s",
node->nickname);
continue;
}
node->use_attempts = use_cnt;
node->use_successes = success_cnt;
log_info(LD_GENERAL, "Read %f/%f path use bias for node %s",
node->use_successes, node->use_attempts, node->nickname);
/* 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(node)/node->use_attempts
< pathbias_get_extreme_use_rate(options) &&
pathbias_get_dropguards(options)) {
node->path_bias_disabled = 1;
log_info(LD_GENERAL,
"Path use bias is too high (%f/%f); disabling node %s",
node->circ_successes, node->circ_attempts, node->nickname);
}
} else if (!strcasecmp(line->key, "EntryGuardPathBias")) {
const or_options_t *options = get_options();
double hop_cnt, success_cnt, timeouts, collapsed, successful_closed,
@ -1144,7 +1178,7 @@ entry_guards_parse_state(or_state_t *state, int set, char **msg)
/* 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(node)/node->circ_attempts
if (pathbias_get_close_success_count(node)/node->circ_attempts
< pathbias_get_extreme_rate(options) &&
pathbias_get_dropguards(options)) {
node->path_bias_disabled = 1;
@ -1282,10 +1316,20 @@ entry_guards_update_state(or_state_t *state)
* unusable_circuits */
tor_asprintf(&line->value, "%f %f %f %f %f %f",
e->circ_attempts, e->circ_successes,
pathbias_get_closed_count(e), e->collapsed_circuits,
pathbias_get_close_success_count(e),
e->collapsed_circuits,
e->unusable_circuits, e->timeouts);
next = &(line->next);
}
if (e->use_attempts > 0) {
*next = line = tor_malloc_zero(sizeof(config_line_t));
line->key = tor_strdup("EntryGuardPathUseBias");
tor_asprintf(&line->value, "%f %f",
e->use_attempts,
pathbias_get_use_success_count(e));
next = &(line->next);
}
} SMARTLIST_FOREACH_END(e);
if (!get_options()->AvoidDiskWrites)

7
src/or/entrynodes.h
View File

@ -61,6 +61,9 @@ typedef struct entry_guard_t {
* attempted, but none succeeded. */
double timeouts; /**< Number of 'right-censored' circuit timeouts for this
* guard. */
double use_attempts; /**< Number of circuits we tried to use with streams */
double use_successes; /**< Number of successfully used circuits using
* this guard as first hop. */
} entry_guard_t;
entry_guard_t *entry_guard_get_by_id_digest(const char *digest);
@ -113,8 +116,8 @@ int find_transport_by_bridge_addrport(const tor_addr_t *addr, uint16_t port,
int validate_pluggable_transports_config(void);
double pathbias_get_closed_count(entry_guard_t *gaurd);
double pathbias_get_success_count(entry_guard_t *guard);
double pathbias_get_close_success_count(entry_guard_t *guard);
double pathbias_get_use_success_count(entry_guard_t *guard);
#endif

32
src/or/or.h
View File

@ -2839,6 +2839,15 @@ typedef enum {
PATH_STATE_BUILD_ATTEMPTED = 1,
/** This circuit has been completely built */
PATH_STATE_BUILD_SUCCEEDED = 2,
/** Did we try to attach any SOCKS streams or hidserv introductions to
* this circuit?
*
* Note: If we ever implement end-to-end stream timing through test
* stream probes (#5707), we must *not* set this for those probes
* (or any other automatic streams) because the adversary could
* just tag at a later point.
*/
PATH_STATE_USE_ATTEMPTED = 3,
/** Did any SOCKS streams or hidserv introductions actually succeed on
* this circuit?
*
@ -2847,13 +2856,20 @@ typedef enum {
* (or any other automatic streams) because the adversary could
* just tag at a later point.
*/
PATH_STATE_USE_SUCCEEDED = 3,
PATH_STATE_USE_SUCCEEDED = 4,
/**
* This is a special state to indicate that we got a corrupted
* relay cell on a circuit and we don't intend to probe it.
*/
PATH_STATE_USE_FAILED = 4,
PATH_STATE_USE_FAILED = 5,
/**
* This is a special state to indicate that we already counted
* the circuit. Used to guard against potential state machine
* violations.
*/
PATH_STATE_ALREADY_COUNTED = 6,
} path_state_t;
/** An origin_circuit_t holds data necessary to build and use a circuit.
@ -2998,7 +3014,6 @@ typedef struct origin_circuit_t {
* ISO_STREAM. */
uint64_t associated_isolated_stream_global_id;
/**@}*/
} origin_circuit_t;
struct onion_queue_t;
@ -3913,7 +3928,16 @@ typedef struct {
int PathBiasScaleThreshold;
int PathBiasScaleFactor;
int PathBiasMultFactor;
int PathBiasUseCloseCounts;
/** @} */
/**
* Parameters for path-bias use detection
* @{
*/
int PathBiasUseThreshold;
double PathBiasNoticeUseRate;
double PathBiasExtremeUseRate;
int PathBiasScaleUseThreshold;
/** @} */
int IPv6Exit; /**< Do we support exiting to IPv6 addresses? */

2
src/or/relay.c
View File

@ -730,7 +730,7 @@ connection_ap_process_end_not_open(
* We rely on recognized+digest being strong enough to make
* tags unlikely to allow us to get tagged, yet 'recognized'
* reason codes here. */
circ->path_state = PATH_STATE_USE_SUCCEEDED;
pathbias_mark_use_success(circ);
}
}

9
src/or/rendclient.c
View File

@ -71,6 +71,9 @@ rend_client_send_establish_rendezvous(origin_circuit_t *circ)
* and the rend cookie also means we've used the circ. */
circ->base_.timestamp_dirty = time(NULL);
/* We've attempted to use this circuit. Probe it if we fail */
pathbias_count_use_attempt(circ);
if (relay_send_command_from_edge(0, TO_CIRCUIT(circ),
RELAY_COMMAND_ESTABLISH_RENDEZVOUS,
circ->rend_data->rend_cookie,
@ -316,6 +319,8 @@ rend_client_send_introduction(origin_circuit_t *introcirc,
* state. */
introcirc->base_.timestamp_dirty = time(NULL);
pathbias_count_use_attempt(introcirc);
goto cleanup;
perm_err:
@ -395,7 +400,7 @@ rend_client_introduction_acked(origin_circuit_t *circ,
/* For path bias: This circuit was used successfully. Valid
* nacks and acks count. */
circ->path_state = PATH_STATE_USE_SUCCEEDED;
pathbias_mark_use_success(circ);
if (request_len == 0) {
/* It's an ACK; the introduction point relayed our introduction request. */
@ -902,7 +907,7 @@ rend_client_rendezvous_acked(origin_circuit_t *circ, const uint8_t *request,
* Waiting any longer opens us up to attacks from Bob. He could induce
* Alice to attempt to connect to his hidden service and never reply
* to her rend requests */
circ->path_state = PATH_STATE_USE_SUCCEEDED;
pathbias_mark_use_success(circ);
/* XXXX This is a pretty brute-force approach. It'd be better to
* attach only the connections that are waiting on this circuit, rather

16
src/or/rendservice.c
View File

@ -1384,9 +1384,6 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request,
goto err;
memcpy(cpath->rend_circ_nonce, keys, DIGEST_LEN);
/* For path bias: This intro circuit was used successfully */
circuit->path_state = PATH_STATE_USE_SUCCEEDED;
goto done;
log_error:
@ -2511,6 +2508,9 @@ rend_service_intro_has_opened(origin_circuit_t *circuit)
goto err;
}
/* We've attempted to use this circuit */
pathbias_count_use_attempt(circuit);
goto done;
err:
@ -2558,6 +2558,10 @@ rend_service_intro_established(origin_circuit_t *circuit,
"Received INTRO_ESTABLISHED cell on circuit %d for service %s",
circuit->base_.n_circ_id, serviceid);
/* Getting a valid INTRODUCE_ESTABLISHED means we've successfully
* used the circ */
pathbias_mark_use_success(circuit);
return 0;
err:
circuit_mark_for_close(TO_CIRCUIT(circuit), END_CIRC_REASON_TORPROTOCOL);
@ -2589,6 +2593,9 @@ rend_service_rendezvous_has_opened(origin_circuit_t *circuit)
if (!circuit->base_.timestamp_dirty)
circuit->base_.timestamp_dirty = time(NULL);
/* This may be redundant */
pathbias_count_use_attempt(circuit);
hop = circuit->build_state->service_pending_final_cpath_ref->cpath;
base16_encode(hexcookie,9,circuit->rend_data->rend_cookie,4);
@ -3061,7 +3068,8 @@ rend_services_introduce(void)
if (intro->time_expiring + INTRO_POINT_EXPIRATION_GRACE_PERIOD > now) {
/* This intro point has completely expired. Remove it, and
* mark the circuit for close if it's still alive. */
if (intro_circ != NULL) {
if (intro_circ != NULL &&
intro_circ->base_.purpose != CIRCUIT_PURPOSE_PATH_BIAS_TESTING) {
circuit_mark_for_close(TO_CIRCUIT(intro_circ),
END_CIRC_REASON_FINISHED);
}