/* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
* Copyright (c) 2007-2012, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file rephist.c
* \brief Basic history and "reputation" functionality to remember
* which servers have worked in the past, how much bandwidth we've
* been using, which ports we tend to want, and so on; further,
* exit port statistics, cell statistics, and connection statistics.
**/
#include "or.h"
#include "circuitlist.h"
#include "circuituse.h"
#include "config.h"
#include "networkstatus.h"
#include "nodelist.h"
#include "rephist.h"
#include "router.h"
#include "routerlist.h"
#include "ht.h"
static void bw_arrays_init(void);
static void predicted_ports_init(void);
/** Total number of bytes currently allocated in fields used by rephist.c. */
uint64_t rephist_total_alloc=0;
/** Number of or_history_t objects currently allocated. */
uint32_t rephist_total_num=0;
/** If the total weighted run count of all runs for a router ever falls
* below this amount, the router can be treated as having 0 MTBF. */
#define STABILITY_EPSILON 0.0001
/** Value by which to discount all old intervals for MTBF purposes. This
* is compounded every STABILITY_INTERVAL. */
#define STABILITY_ALPHA 0.95
/** Interval at which to discount all old intervals for MTBF purposes. */
#define STABILITY_INTERVAL (12*60*60)
/* (This combination of ALPHA, INTERVAL, and EPSILON makes it so that an
* interval that just ended counts twice as much as one that ended a week ago,
* 20X as much as one that ended a month ago, and routers that have had no
* uptime data for about half a year will get forgotten.) */
/** History of an OR-\>OR link. */
typedef struct link_history_t {
/** When did we start tracking this list? */
time_t since;
/** When did we most recently note a change to this link */
time_t changed;
/** How many times did extending from OR1 to OR2 succeed? */
unsigned long n_extend_ok;
/** How many times did extending from OR1 to OR2 fail? */
unsigned long n_extend_fail;
} link_history_t;
/** History of an OR. */
typedef struct or_history_t {
/** When did we start tracking this OR? */
time_t since;
/** When did we most recently note a change to this OR? */
time_t changed;
/** How many times did we successfully connect? */
unsigned long n_conn_ok;
/** How many times did we try to connect and fail?*/
unsigned long n_conn_fail;
/** How many seconds have we been connected to this OR before
* 'up_since'? */
unsigned long uptime;
/** How many seconds have we been unable to connect to this OR before
* 'down_since'? */
unsigned long downtime;
/** If nonzero, we have been connected since this time. */
time_t up_since;
/** If nonzero, we have been unable to connect since this time. */
time_t down_since;
/** The address at which we most recently connected to this OR
* successfully. */
tor_addr_t last_reached_addr;
/** The port at which we most recently connected to this OR successfully */
uint16_t last_reached_port;
/* === For MTBF tracking: */
/** Weighted sum total of all times that this router has been online.
*/
unsigned long weighted_run_length;
/** If the router is now online (according to stability-checking rules),
* when did it come online? */
time_t start_of_run;
/** Sum of weights for runs in weighted_run_length. */
double total_run_weights;
/* === For fractional uptime tracking: */
time_t start_of_downtime;
unsigned long weighted_uptime;
unsigned long total_weighted_time;
/** Map from hex OR2 identity digest to a link_history_t for the link
* from this OR to OR2. */
digestmap_t *link_history_map;
} or_history_t;
/** When did we last multiply all routers' weighted_run_length and
* total_run_weights by STABILITY_ALPHA? */
static time_t stability_last_downrated = 0;
/** */
static time_t started_tracking_stability = 0;
/** Map from hex OR identity digest to or_history_t. */
static digestmap_t *history_map = NULL;
/** Return the or_history_t for the OR with identity digest id,
* creating it if necessary. */
static or_history_t *
get_or_history(const char* id)
{
or_history_t *hist;
if (tor_digest_is_zero(id))
return NULL;
hist = digestmap_get(history_map, id);
if (!hist) {
hist = tor_malloc_zero(sizeof(or_history_t));
rephist_total_alloc += sizeof(or_history_t);
rephist_total_num++;
hist->link_history_map = digestmap_new();
hist->since = hist->changed = time(NULL);
tor_addr_make_unspec(&hist->last_reached_addr);
digestmap_set(history_map, id, hist);
}
return hist;
}
/** Return the link_history_t for the link from the first named OR to
* the second, creating it if necessary. (ORs are identified by
* identity digest.)
*/
static link_history_t *
get_link_history(const char *from_id, const char *to_id)
{
or_history_t *orhist;
link_history_t *lhist;
orhist = get_or_history(from_id);
if (!orhist)
return NULL;
if (tor_digest_is_zero(to_id))
return NULL;
lhist = (link_history_t*) digestmap_get(orhist->link_history_map, to_id);
if (!lhist) {
lhist = tor_malloc_zero(sizeof(link_history_t));
rephist_total_alloc += sizeof(link_history_t);
lhist->since = lhist->changed = time(NULL);
digestmap_set(orhist->link_history_map, to_id, lhist);
}
return lhist;
}
/** Helper: free storage held by a single link history entry. */
static void
_free_link_history(void *val)
{
rephist_total_alloc -= sizeof(link_history_t);
tor_free(val);
}
/** Helper: free storage held by a single OR history entry. */
static void
free_or_history(void *_hist)
{
or_history_t *hist = _hist;
digestmap_free(hist->link_history_map, _free_link_history);
rephist_total_alloc -= sizeof(or_history_t);
rephist_total_num--;
tor_free(hist);
}
/** Update an or_history_t object hist so that its uptime/downtime
* count is up-to-date as of when.
*/
static void
update_or_history(or_history_t *hist, time_t when)
{
tor_assert(hist);
if (hist->up_since) {
tor_assert(!hist->down_since);
hist->uptime += (when - hist->up_since);
hist->up_since = when;
} else if (hist->down_since) {
hist->downtime += (when - hist->down_since);
hist->down_since = when;
}
}
/** Initialize the static data structures for tracking history. */
void
rep_hist_init(void)
{
history_map = digestmap_new();
bw_arrays_init();
predicted_ports_init();
}
/** Helper: note that we are no longer connected to the router with history
* hist. If failed, the connection failed; otherwise, it was
* closed correctly. */
static void
mark_or_down(or_history_t *hist, time_t when, int failed)
{
if (hist->up_since) {
hist->uptime += (when - hist->up_since);
hist->up_since = 0;
}
if (failed && !hist->down_since) {
hist->down_since = when;
}
}
/** Helper: note that we are connected to the router with history
* hist. */
static void
mark_or_up(or_history_t *hist, time_t when)
{
if (hist->down_since) {
hist->downtime += (when - hist->down_since);
hist->down_since = 0;
}
if (!hist->up_since) {
hist->up_since = when;
}
}
/** Remember that an attempt to connect to the OR with identity digest
* id failed at when.
*/
void
rep_hist_note_connect_failed(const char* id, time_t when)
{
or_history_t *hist;
hist = get_or_history(id);
if (!hist)
return;
++hist->n_conn_fail;
mark_or_down(hist, when, 1);
hist->changed = when;
}
/** Remember that an attempt to connect to the OR with identity digest
* id succeeded at when.
*/
void
rep_hist_note_connect_succeeded(const char* id, time_t when)
{
or_history_t *hist;
hist = get_or_history(id);
if (!hist)
return;
++hist->n_conn_ok;
mark_or_up(hist, when);
hist->changed = when;
}
/** Remember that we intentionally closed our connection to the OR
* with identity digest id at when.
*/
void
rep_hist_note_disconnect(const char* id, time_t when)
{
or_history_t *hist;
hist = get_or_history(id);
if (!hist)
return;
mark_or_down(hist, when, 0);
hist->changed = when;
}
/** Remember that our connection to the OR with identity digest
* id had an error and stopped working at when.
*/
void
rep_hist_note_connection_died(const char* id, time_t when)
{
or_history_t *hist;
if (!id) {
/* If conn has no identity, it didn't complete its handshake, or something
* went wrong. Ignore it.
*/
return;
}
hist = get_or_history(id);
if (!hist)
return;
mark_or_down(hist, when, 1);
hist->changed = when;
}
/** We have just decided that this router with identity digest id is
* reachable, meaning we will give it a "Running" flag for the next while. */
void
rep_hist_note_router_reachable(const char *id, const tor_addr_t *at_addr,
const uint16_t at_port, time_t when)
{
or_history_t *hist = get_or_history(id);
int was_in_run = 1;
char tbuf[ISO_TIME_LEN+1];
int addr_changed, port_changed;
tor_assert(hist);
tor_assert((!at_addr && !at_port) || (at_addr && at_port));
addr_changed = at_addr &&
tor_addr_compare(at_addr, &hist->last_reached_addr, CMP_EXACT) != 0;
port_changed = at_port && at_port != hist->last_reached_port;
if (!started_tracking_stability)
started_tracking_stability = time(NULL);
if (!hist->start_of_run) {
hist->start_of_run = when;
was_in_run = 0;
}
if (hist->start_of_downtime) {
long down_length;
format_local_iso_time(tbuf, hist->start_of_downtime);
log_info(LD_HIST, "Router %s is now Running; it had been down since %s.",
hex_str(id, DIGEST_LEN), tbuf);
if (was_in_run)
log_info(LD_HIST, " (Paradoxically, it was already Running too.)");
down_length = when - hist->start_of_downtime;
hist->total_weighted_time += down_length;
hist->start_of_downtime = 0;
} else if (addr_changed || port_changed) {
/* If we're reachable, but the address changed, treat this as some
* downtime. */
int penalty = get_options()->TestingTorNetwork ? 240 : 3600;
networkstatus_t *ns;
if ((ns = networkstatus_get_latest_consensus())) {
int fresh_interval = (int)(ns->fresh_until - ns->valid_after);
int live_interval = (int)(ns->valid_until - ns->valid_after);
/* on average, a descriptor addr change takes .5 intervals to make it
* into a consensus, and half a liveness period to make it to
* clients. */
penalty = (int)(fresh_interval + live_interval) / 2;
}
format_local_iso_time(tbuf, hist->start_of_run);
log_info(LD_HIST,"Router %s still seems Running, but its address appears "
"to have changed since the last time it was reachable. I'm "
"going to treat it as having been down for %d seconds",
hex_str(id, DIGEST_LEN), penalty);
rep_hist_note_router_unreachable(id, when-penalty);
rep_hist_note_router_reachable(id, NULL, 0, when);
} else {
format_local_iso_time(tbuf, hist->start_of_run);
if (was_in_run)
log_debug(LD_HIST, "Router %s is still Running; it has been Running "
"since %s", hex_str(id, DIGEST_LEN), tbuf);
else
log_info(LD_HIST,"Router %s is now Running; it was previously untracked",
hex_str(id, DIGEST_LEN));
}
if (at_addr)
tor_addr_copy(&hist->last_reached_addr, at_addr);
if (at_port)
hist->last_reached_port = at_port;
}
/** We have just decided that this router is unreachable, meaning
* we are taking away its "Running" flag. */
void
rep_hist_note_router_unreachable(const char *id, time_t when)
{
or_history_t *hist = get_or_history(id);
char tbuf[ISO_TIME_LEN+1];
int was_running = 0;
if (!started_tracking_stability)
started_tracking_stability = time(NULL);
tor_assert(hist);
if (hist->start_of_run) {
/*XXXX We could treat failed connections differently from failed
* connect attempts. */
long run_length = when - hist->start_of_run;
format_local_iso_time(tbuf, hist->start_of_run);
hist->total_run_weights += 1.0;
hist->start_of_run = 0;
if (run_length < 0) {
unsigned long penalty = -run_length;
#define SUBTRACT_CLAMPED(var, penalty) \
do { (var) = (var) < (penalty) ? 0 : (var) - (penalty); } while (0)
SUBTRACT_CLAMPED(hist->weighted_run_length, penalty);
SUBTRACT_CLAMPED(hist->weighted_uptime, penalty);
} else {
hist->weighted_run_length += run_length;
hist->weighted_uptime += run_length;
hist->total_weighted_time += run_length;
}
was_running = 1;
log_info(LD_HIST, "Router %s is now non-Running: it had previously been "
"Running since %s. Its total weighted uptime is %lu/%lu.",
hex_str(id, DIGEST_LEN), tbuf, hist->weighted_uptime,
hist->total_weighted_time);
}
if (!hist->start_of_downtime) {
hist->start_of_downtime = when;
if (!was_running)
log_info(LD_HIST, "Router %s is now non-Running; it was previously "
"untracked.", hex_str(id, DIGEST_LEN));
} else {
if (!was_running) {
format_local_iso_time(tbuf, hist->start_of_downtime);
log_info(LD_HIST, "Router %s is still non-Running; it has been "
"non-Running since %s.", hex_str(id, DIGEST_LEN), tbuf);
}
}
}
/** Helper: Discount all old MTBF data, if it is time to do so. Return
* the time at which we should next discount MTBF data. */
time_t
rep_hist_downrate_old_runs(time_t now)
{
digestmap_iter_t *orhist_it;
const char *digest1;
or_history_t *hist;
void *hist_p;
double alpha = 1.0;
if (!history_map)
history_map = digestmap_new();
if (!stability_last_downrated)
stability_last_downrated = now;
if (stability_last_downrated + STABILITY_INTERVAL > now)
return stability_last_downrated + STABILITY_INTERVAL;
/* Okay, we should downrate the data. By how much? */
while (stability_last_downrated + STABILITY_INTERVAL < now) {
stability_last_downrated += STABILITY_INTERVAL;
alpha *= STABILITY_ALPHA;
}
log_info(LD_HIST, "Discounting all old stability info by a factor of %f",
alpha);
/* Multiply every w_r_l, t_r_w pair by alpha. */
for (orhist_it = digestmap_iter_init(history_map);
!digestmap_iter_done(orhist_it);
orhist_it = digestmap_iter_next(history_map,orhist_it)) {
digestmap_iter_get(orhist_it, &digest1, &hist_p);
hist = hist_p;
hist->weighted_run_length =
(unsigned long)(hist->weighted_run_length * alpha);
hist->total_run_weights *= alpha;
hist->weighted_uptime = (unsigned long)(hist->weighted_uptime * alpha);
hist->total_weighted_time = (unsigned long)
(hist->total_weighted_time * alpha);
}
return stability_last_downrated + STABILITY_INTERVAL;
}
/** Helper: Return the weighted MTBF of the router with history hist. */
static double
get_stability(or_history_t *hist, time_t when)
{
long total = hist->weighted_run_length;
double total_weights = hist->total_run_weights;
if (hist->start_of_run) {
/* We're currently in a run. Let total and total_weights hold the values
* they would hold if the current run were to end now. */
total += (when-hist->start_of_run);
total_weights += 1.0;
}
if (total_weights < STABILITY_EPSILON) {
/* Round down to zero, and avoid divide-by-zero. */
return 0.0;
}
return total / total_weights;
}
/** Return the total amount of time we've been observing, with each run of
* time downrated by the appropriate factor. */
static long
get_total_weighted_time(or_history_t *hist, time_t when)
{
long total = hist->total_weighted_time;
if (hist->start_of_run) {
total += (when - hist->start_of_run);
} else if (hist->start_of_downtime) {
total += (when - hist->start_of_downtime);
}
return total;
}
/** Helper: Return the weighted percent-of-time-online of the router with
* history hist. */
static double
get_weighted_fractional_uptime(or_history_t *hist, time_t when)
{
long total = hist->total_weighted_time;
long up = hist->weighted_uptime;
if (hist->start_of_run) {
long run_length = (when - hist->start_of_run);
up += run_length;
total += run_length;
} else if (hist->start_of_downtime) {
total += (when - hist->start_of_downtime);
}
if (!total) {
/* Avoid calling anybody's uptime infinity (which should be impossible if
* the code is working), or NaN (which can happen for any router we haven't
* observed up or down yet). */
return 0.0;
}
return ((double) up) / total;
}
/** Return how long the router whose identity digest is id has
* been reachable. Return 0 if the router is unknown or currently deemed
* unreachable. */
long
rep_hist_get_uptime(const char *id, time_t when)
{
or_history_t *hist = get_or_history(id);
if (!hist)
return 0;
if (!hist->start_of_run || when < hist->start_of_run)
return 0;
return when - hist->start_of_run;
}
/** Return an estimated MTBF for the router whose identity digest is
* id. Return 0 if the router is unknown. */
double
rep_hist_get_stability(const char *id, time_t when)
{
or_history_t *hist = get_or_history(id);
if (!hist)
return 0.0;
return get_stability(hist, when);
}
/** Return an estimated percent-of-time-online for the router whose identity
* digest is id. Return 0 if the router is unknown. */
double
rep_hist_get_weighted_fractional_uptime(const char *id, time_t when)
{
or_history_t *hist = get_or_history(id);
if (!hist)
return 0.0;
return get_weighted_fractional_uptime(hist, when);
}
/** Return a number representing how long we've known about the router whose
* digest is id. Return 0 if the router is unknown.
*
* Be careful: this measure increases monotonically as we know the router for
* longer and longer, but it doesn't increase linearly.
*/
long
rep_hist_get_weighted_time_known(const char *id, time_t when)
{
or_history_t *hist = get_or_history(id);
if (!hist)
return 0;
return get_total_weighted_time(hist, when);
}
/** Return true if we've been measuring MTBFs for long enough to
* pronounce on Stability. */
int
rep_hist_have_measured_enough_stability(void)
{
/* XXXX023 This doesn't do so well when we change our opinion
* as to whether we're tracking router stability. */
return started_tracking_stability < time(NULL) - 4*60*60;
}
/** Remember that we successfully extended from the OR with identity
* digest from_id to the OR with identity digest
* to_name.
*/
void
rep_hist_note_extend_succeeded(const char *from_id, const char *to_id)
{
link_history_t *hist;
/* log_fn(LOG_WARN, "EXTEND SUCCEEDED: %s->%s",from_name,to_name); */
hist = get_link_history(from_id, to_id);
if (!hist)
return;
++hist->n_extend_ok;
hist->changed = time(NULL);
}
/** Remember that we tried to extend from the OR with identity digest
* from_id to the OR with identity digest to_name, but
* failed.
*/
void
rep_hist_note_extend_failed(const char *from_id, const char *to_id)
{
link_history_t *hist;
/* log_fn(LOG_WARN, "EXTEND FAILED: %s->%s",from_name,to_name); */
hist = get_link_history(from_id, to_id);
if (!hist)
return;
++hist->n_extend_fail;
hist->changed = time(NULL);
}
/** Log all the reliability data we have remembered, with the chosen
* severity.
*/
void
rep_hist_dump_stats(time_t now, int severity)
{
digestmap_iter_t *lhist_it;
digestmap_iter_t *orhist_it;
const char *name1, *name2, *digest1, *digest2;
char hexdigest1[HEX_DIGEST_LEN+1];
char hexdigest2[HEX_DIGEST_LEN+1];
or_history_t *or_history;
link_history_t *link_history;
void *or_history_p, *link_history_p;
double uptime;
char buffer[2048];
size_t len;
int ret;
unsigned long upt, downt;
const node_t *node;
rep_history_clean(now - get_options()->RephistTrackTime);
log(severity, LD_HIST, "--------------- Dumping history information:");
for (orhist_it = digestmap_iter_init(history_map);
!digestmap_iter_done(orhist_it);
orhist_it = digestmap_iter_next(history_map,orhist_it)) {
double s;
long stability;
digestmap_iter_get(orhist_it, &digest1, &or_history_p);
or_history = (or_history_t*) or_history_p;
if ((node = node_get_by_id(digest1)) && node_get_nickname(node))
name1 = node_get_nickname(node);
else
name1 = "(unknown)";
base16_encode(hexdigest1, sizeof(hexdigest1), digest1, DIGEST_LEN);
update_or_history(or_history, now);
upt = or_history->uptime;
downt = or_history->downtime;
s = get_stability(or_history, now);
stability = (long)s;
if (upt+downt) {
uptime = ((double)upt) / (upt+downt);
} else {
uptime=1.0;
}
log(severity, LD_HIST,
"OR %s [%s]: %ld/%ld good connections; uptime %ld/%ld sec (%.2f%%); "
"wmtbf %lu:%02lu:%02lu",
name1, hexdigest1,
or_history->n_conn_ok, or_history->n_conn_fail+or_history->n_conn_ok,
upt, upt+downt, uptime*100.0,
stability/3600, (stability/60)%60, stability%60);
if (!digestmap_isempty(or_history->link_history_map)) {
strlcpy(buffer, " Extend attempts: ", sizeof(buffer));
len = strlen(buffer);
for (lhist_it = digestmap_iter_init(or_history->link_history_map);
!digestmap_iter_done(lhist_it);
lhist_it = digestmap_iter_next(or_history->link_history_map,
lhist_it)) {
digestmap_iter_get(lhist_it, &digest2, &link_history_p);
if ((node = node_get_by_id(digest2)) && node_get_nickname(node))
name2 = node_get_nickname(node);
else
name2 = "(unknown)";
link_history = (link_history_t*) link_history_p;
base16_encode(hexdigest2, sizeof(hexdigest2), digest2, DIGEST_LEN);
ret = tor_snprintf(buffer+len, 2048-len, "%s [%s](%ld/%ld); ",
name2,
hexdigest2,
link_history->n_extend_ok,
link_history->n_extend_ok+link_history->n_extend_fail);
if (ret<0)
break;
else
len += ret;
}
log(severity, LD_HIST, "%s", buffer);
}
}
}
/** Remove history info for routers/links that haven't changed since
* before.
*/
void
rep_history_clean(time_t before)
{
int authority = authdir_mode(get_options());
or_history_t *or_history;
link_history_t *link_history;
void *or_history_p, *link_history_p;
digestmap_iter_t *orhist_it, *lhist_it;
const char *d1, *d2;
orhist_it = digestmap_iter_init(history_map);
while (!digestmap_iter_done(orhist_it)) {
int remove;
digestmap_iter_get(orhist_it, &d1, &or_history_p);
or_history = or_history_p;
remove = authority ? (or_history->total_run_weights < STABILITY_EPSILON &&
!or_history->start_of_run)
: (or_history->changed < before);
if (remove) {
orhist_it = digestmap_iter_next_rmv(history_map, orhist_it);
free_or_history(or_history);
continue;
}
for (lhist_it = digestmap_iter_init(or_history->link_history_map);
!digestmap_iter_done(lhist_it); ) {
digestmap_iter_get(lhist_it, &d2, &link_history_p);
link_history = link_history_p;
if (link_history->changed < before) {
lhist_it = digestmap_iter_next_rmv(or_history->link_history_map,
lhist_it);
rephist_total_alloc -= sizeof(link_history_t);
tor_free(link_history);
continue;
}
lhist_it = digestmap_iter_next(or_history->link_history_map,lhist_it);
}
orhist_it = digestmap_iter_next(history_map, orhist_it);
}
}
/** Write MTBF data to disk. Return 0 on success, negative on failure.
*
* If missing_means_down, then if we're about to write an entry
* that is still considered up but isn't in our routerlist, consider it
* to be down. */
int
rep_hist_record_mtbf_data(time_t now, int missing_means_down)
{
char time_buf[ISO_TIME_LEN+1];
digestmap_iter_t *orhist_it;
const char *digest;
void *or_history_p;
or_history_t *hist;
open_file_t *open_file = NULL;
FILE *f;
{
char *filename = get_datadir_fname("router-stability");
f = start_writing_to_stdio_file(filename, OPEN_FLAGS_REPLACE|O_TEXT, 0600,
&open_file);
tor_free(filename);
if (!f)
return -1;
}
/* File format is:
* FormatLine *KeywordLine Data
*
* FormatLine = "format 1" NL
* KeywordLine = Keyword SP Arguments NL
* Data = "data" NL *RouterMTBFLine "." NL
* RouterMTBFLine = Fingerprint SP WeightedRunLen SP
* TotalRunWeights [SP S=StartRunTime] NL
*/
#define PUT(s) STMT_BEGIN if (fputs((s),f)<0) goto err; STMT_END
#define PRINTF(args) STMT_BEGIN if (fprintf args <0) goto err; STMT_END
PUT("format 2\n");
format_iso_time(time_buf, time(NULL));
PRINTF((f, "stored-at %s\n", time_buf));
if (started_tracking_stability) {
format_iso_time(time_buf, started_tracking_stability);
PRINTF((f, "tracked-since %s\n", time_buf));
}
if (stability_last_downrated) {
format_iso_time(time_buf, stability_last_downrated);
PRINTF((f, "last-downrated %s\n", time_buf));
}
PUT("data\n");
/* XXX Nick: now bridge auths record this for all routers too.
* Should we make them record it only for bridge routers? -RD
* Not for 0.2.0. -NM */
for (orhist_it = digestmap_iter_init(history_map);
!digestmap_iter_done(orhist_it);
orhist_it = digestmap_iter_next(history_map,orhist_it)) {
char dbuf[HEX_DIGEST_LEN+1];
const char *t = NULL;
digestmap_iter_get(orhist_it, &digest, &or_history_p);
hist = (or_history_t*) or_history_p;
base16_encode(dbuf, sizeof(dbuf), digest, DIGEST_LEN);
if (missing_means_down && hist->start_of_run &&
!router_get_by_id_digest(digest)) {
/* We think this relay is running, but it's not listed in our
* routerlist. Somehow it fell out without telling us it went
* down. Complain and also correct it. */
log_info(LD_HIST,
"Relay '%s' is listed as up in rephist, but it's not in "
"our routerlist. Correcting.", dbuf);
rep_hist_note_router_unreachable(digest, now);
}
PRINTF((f, "R %s\n", dbuf));
if (hist->start_of_run > 0) {
format_iso_time(time_buf, hist->start_of_run);
t = time_buf;
}
PRINTF((f, "+MTBF %lu %.5f%s%s\n",
hist->weighted_run_length, hist->total_run_weights,
t ? " S=" : "", t ? t : ""));
t = NULL;
if (hist->start_of_downtime > 0) {
format_iso_time(time_buf, hist->start_of_downtime);
t = time_buf;
}
PRINTF((f, "+WFU %lu %lu%s%s\n",
hist->weighted_uptime, hist->total_weighted_time,
t ? " S=" : "", t ? t : ""));
}
PUT(".\n");
#undef PUT
#undef PRINTF
return finish_writing_to_file(open_file);
err:
abort_writing_to_file(open_file);
return -1;
}
/** Format the current tracked status of the router in hist at time
* now for analysis; return it in a newly allocated string. */
static char *
rep_hist_format_router_status(or_history_t *hist, time_t now)
{
char sor_buf[ISO_TIME_LEN+1];
char sod_buf[ISO_TIME_LEN+1];
double wfu;
double mtbf;
int up = 0, down = 0;
char *cp = NULL;
if (hist->start_of_run) {
format_iso_time(sor_buf, hist->start_of_run);
up = 1;
}
if (hist->start_of_downtime) {
format_iso_time(sod_buf, hist->start_of_downtime);
down = 1;
}
wfu = get_weighted_fractional_uptime(hist, now);
mtbf = get_stability(hist, now);
tor_asprintf(&cp,
"%s%s%s"
"%s%s%s"
"wfu %0.3f\n"
" weighted-time %lu\n"
" weighted-uptime %lu\n"
"mtbf %0.1f\n"
" weighted-run-length %lu\n"
" total-run-weights %f\n",
up?"uptime-started ":"", up?sor_buf:"", up?" UTC\n":"",
down?"downtime-started ":"", down?sod_buf:"", down?" UTC\n":"",
wfu,
hist->total_weighted_time,
hist->weighted_uptime,
mtbf,
hist->weighted_run_length,
hist->total_run_weights
);
return cp;
}
/** The last stability analysis document that we created, or NULL if we never
* have created one. */
static char *last_stability_doc = NULL;
/** The last time we created a stability analysis document, or 0 if we never
* have created one. */
static time_t built_last_stability_doc_at = 0;
/** Shortest allowable time between building two stability documents. */
#define MAX_STABILITY_DOC_BUILD_RATE (3*60)
/** Return a pointer to a NUL-terminated document describing our view of the
* stability of the routers we've been tracking. Return NULL on failure. */
const char *
rep_hist_get_router_stability_doc(time_t now)
{
char *result;
smartlist_t *chunks;
if (built_last_stability_doc_at + MAX_STABILITY_DOC_BUILD_RATE > now)
return last_stability_doc;
if (!history_map)
return NULL;
tor_free(last_stability_doc);
chunks = smartlist_new();
if (rep_hist_have_measured_enough_stability()) {
smartlist_add(chunks, tor_strdup("we-have-enough-measurements\n"));
} else {
smartlist_add(chunks, tor_strdup("we-do-not-have-enough-measurements\n"));
}
DIGESTMAP_FOREACH(history_map, id, or_history_t *, hist) {
const node_t *node;
char dbuf[BASE64_DIGEST_LEN+1];
char *info;
digest_to_base64(dbuf, id);
node = node_get_by_id(id);
if (node) {
char ip[INET_NTOA_BUF_LEN+1];
char tbuf[ISO_TIME_LEN+1];
time_t published = node_get_published_on(node);
node_get_address_string(node,ip,sizeof(ip));
if (published > 0)
format_iso_time(tbuf, published);
else
strlcpy(tbuf, "???", sizeof(tbuf));
smartlist_add_asprintf(chunks,
"router %s %s %s\n"
"published %s\n"
"relevant-flags %s%s%s\n"
"declared-uptime %ld\n",
dbuf, node_get_nickname(node), ip,
tbuf,
node->is_running ? "Running " : "",
node->is_valid ? "Valid " : "",
node->ri && node->ri->is_hibernating ? "Hibernating " : "",
node_get_declared_uptime(node));
} else {
smartlist_add_asprintf(chunks,
"router %s {no descriptor}\n", dbuf);
}
info = rep_hist_format_router_status(hist, now);
if (info)
smartlist_add(chunks, info);
} DIGESTMAP_FOREACH_END;
result = smartlist_join_strings(chunks, "", 0, NULL);
SMARTLIST_FOREACH(chunks, char *, cp, tor_free(cp));
smartlist_free(chunks);
last_stability_doc = result;
built_last_stability_doc_at = time(NULL);
return result;
}
/** Helper: return the first j >= i such that !strcmpstart(sl[j], prefix) and
* such that no line sl[k] with i <= k < j starts with "R ". Return -1 if no
* such line exists. */
static int
find_next_with(smartlist_t *sl, int i, const char *prefix)
{
for ( ; i < smartlist_len(sl); ++i) {
const char *line = smartlist_get(sl, i);
if (!strcmpstart(line, prefix))
return i;
if (!strcmpstart(line, "R "))
return -1;
}
return -1;
}
/** How many bad times has parse_possibly_bad_iso_time() parsed? */
static int n_bogus_times = 0;
/** Parse the ISO-formatted time in s into *time_out, but
* round any pre-1970 date to Jan 1, 1970. */
static int
parse_possibly_bad_iso_time(const char *s, time_t *time_out)
{
int year;
char b[5];
strlcpy(b, s, sizeof(b));
b[4] = '\0';
year = (int)tor_parse_long(b, 10, 0, INT_MAX, NULL, NULL);
if (year < 1970) {
*time_out = 0;
++n_bogus_times;
return 0;
} else
return parse_iso_time(s, time_out);
}
/** We've read a time t from a file stored at stored_at, which
* says we started measuring at started_measuring. Return a new number
* that's about as much before now as t was before
* stored_at.
*/
static INLINE time_t
correct_time(time_t t, time_t now, time_t stored_at, time_t started_measuring)
{
if (t < started_measuring - 24*60*60*365)
return 0;
else if (t < started_measuring)
return started_measuring;
else if (t > stored_at)
return 0;
else {
long run_length = stored_at - t;
t = now - run_length;
if (t < started_measuring)
t = started_measuring;
return t;
}
}
/** Load MTBF data from disk. Returns 0 on success or recoverable error, -1
* on failure. */
int
rep_hist_load_mtbf_data(time_t now)
{
/* XXXX won't handle being called while history is already populated. */
smartlist_t *lines;
const char *line = NULL;
int r=0, i;
time_t last_downrated = 0, stored_at = 0, tracked_since = 0;
time_t latest_possible_start = now;
long format = -1;
{
char *filename = get_datadir_fname("router-stability");
char *d = read_file_to_str(filename, RFTS_IGNORE_MISSING, NULL);
tor_free(filename);
if (!d)
return -1;
lines = smartlist_new();
smartlist_split_string(lines, d, "\n", SPLIT_SKIP_SPACE, 0);
tor_free(d);
}
{
const char *firstline;
if (smartlist_len(lines)>4) {
firstline = smartlist_get(lines, 0);
if (!strcmpstart(firstline, "format "))
format = tor_parse_long(firstline+strlen("format "),
10, -1, LONG_MAX, NULL, NULL);
}
}
if (format != 1 && format != 2) {
log_warn(LD_HIST,
"Unrecognized format in mtbf history file. Skipping.");
goto err;
}
for (i = 1; i < smartlist_len(lines); ++i) {
line = smartlist_get(lines, i);
if (!strcmp(line, "data"))
break;
if (!strcmpstart(line, "last-downrated ")) {
if (parse_iso_time(line+strlen("last-downrated "), &last_downrated)<0)
log_warn(LD_HIST,"Couldn't parse downrate time in mtbf "
"history file.");
}
if (!strcmpstart(line, "stored-at ")) {
if (parse_iso_time(line+strlen("stored-at "), &stored_at)<0)
log_warn(LD_HIST,"Couldn't parse stored time in mtbf "
"history file.");
}
if (!strcmpstart(line, "tracked-since ")) {
if (parse_iso_time(line+strlen("tracked-since "), &tracked_since)<0)
log_warn(LD_HIST,"Couldn't parse started-tracking time in mtbf "
"history file.");
}
}
if (last_downrated > now)
last_downrated = now;
if (tracked_since > now)
tracked_since = now;
if (!stored_at) {
log_warn(LD_HIST, "No stored time recorded.");
goto err;
}
if (line && !strcmp(line, "data"))
++i;
n_bogus_times = 0;
for (; i < smartlist_len(lines); ++i) {
char digest[DIGEST_LEN];
char hexbuf[HEX_DIGEST_LEN+1];
char mtbf_timebuf[ISO_TIME_LEN+1];
char wfu_timebuf[ISO_TIME_LEN+1];
time_t start_of_run = 0;
time_t start_of_downtime = 0;
int have_mtbf = 0, have_wfu = 0;
long wrl = 0;
double trw = 0;
long wt_uptime = 0, total_wt_time = 0;
int n;
or_history_t *hist;
line = smartlist_get(lines, i);
if (!strcmp(line, "."))
break;
mtbf_timebuf[0] = '\0';
wfu_timebuf[0] = '\0';
if (format == 1) {
n = sscanf(line, "%40s %ld %lf S=%10s %8s",
hexbuf, &wrl, &trw, mtbf_timebuf, mtbf_timebuf+11);
if (n != 3 && n != 5) {
log_warn(LD_HIST, "Couldn't scan line %s", escaped(line));
continue;
}
have_mtbf = 1;
} else {
// format == 2.
int mtbf_idx, wfu_idx;
if (strcmpstart(line, "R ") || strlen(line) < 2+HEX_DIGEST_LEN)
continue;
strlcpy(hexbuf, line+2, sizeof(hexbuf));
mtbf_idx = find_next_with(lines, i+1, "+MTBF ");
wfu_idx = find_next_with(lines, i+1, "+WFU ");
if (mtbf_idx >= 0) {
const char *mtbfline = smartlist_get(lines, mtbf_idx);
n = sscanf(mtbfline, "+MTBF %lu %lf S=%10s %8s",
&wrl, &trw, mtbf_timebuf, mtbf_timebuf+11);
if (n == 2 || n == 4) {
have_mtbf = 1;
} else {
log_warn(LD_HIST, "Couldn't scan +MTBF line %s",
escaped(mtbfline));
}
}
if (wfu_idx >= 0) {
const char *wfuline = smartlist_get(lines, wfu_idx);
n = sscanf(wfuline, "+WFU %lu %lu S=%10s %8s",
&wt_uptime, &total_wt_time,
wfu_timebuf, wfu_timebuf+11);
if (n == 2 || n == 4) {
have_wfu = 1;
} else {
log_warn(LD_HIST, "Couldn't scan +WFU line %s", escaped(wfuline));
}
}
if (wfu_idx > i)
i = wfu_idx;
if (mtbf_idx > i)
i = mtbf_idx;
}
if (base16_decode(digest, DIGEST_LEN, hexbuf, HEX_DIGEST_LEN) < 0) {
log_warn(LD_HIST, "Couldn't hex string %s", escaped(hexbuf));
continue;
}
hist = get_or_history(digest);
if (!hist)
continue;
if (have_mtbf) {
if (mtbf_timebuf[0]) {
mtbf_timebuf[10] = ' ';
if (parse_possibly_bad_iso_time(mtbf_timebuf, &start_of_run)<0)
log_warn(LD_HIST, "Couldn't parse time %s",
escaped(mtbf_timebuf));
}
hist->start_of_run = correct_time(start_of_run, now, stored_at,
tracked_since);
if (hist->start_of_run < latest_possible_start + wrl)
latest_possible_start = hist->start_of_run - wrl;
hist->weighted_run_length = wrl;
hist->total_run_weights = trw;
}
if (have_wfu) {
if (wfu_timebuf[0]) {
wfu_timebuf[10] = ' ';
if (parse_possibly_bad_iso_time(wfu_timebuf, &start_of_downtime)<0)
log_warn(LD_HIST, "Couldn't parse time %s", escaped(wfu_timebuf));
}
}
hist->start_of_downtime = correct_time(start_of_downtime, now, stored_at,
tracked_since);
hist->weighted_uptime = wt_uptime;
hist->total_weighted_time = total_wt_time;
}
if (strcmp(line, "."))
log_warn(LD_HIST, "Truncated MTBF file.");
if (tracked_since < 86400*365) /* Recover from insanely early value. */
tracked_since = latest_possible_start;
stability_last_downrated = last_downrated;
started_tracking_stability = tracked_since;
goto done;
err:
r = -1;
done:
SMARTLIST_FOREACH(lines, char *, cp, tor_free(cp));
smartlist_free(lines);
return r;
}
/** For how many seconds do we keep track of individual per-second bandwidth
* totals? */
#define NUM_SECS_ROLLING_MEASURE 10
/** How large are the intervals for which we track and report bandwidth use? */
/* XXXX Watch out! Before Tor 0.2.2.21-alpha, using any other value here would
* generate an unparseable state file. */
#define NUM_SECS_BW_SUM_INTERVAL (15*60)
/** How far in the past do we remember and publish bandwidth use? */
#define NUM_SECS_BW_SUM_IS_VALID (24*60*60)
/** How many bandwidth usage intervals do we remember? (derived) */
#define NUM_TOTALS (NUM_SECS_BW_SUM_IS_VALID/NUM_SECS_BW_SUM_INTERVAL)
/** Structure to track bandwidth use, and remember the maxima for a given
* time period.
*/
typedef struct bw_array_t {
/** Observation array: Total number of bytes transferred in each of the last
* NUM_SECS_ROLLING_MEASURE seconds. This is used as a circular array. */
uint64_t obs[NUM_SECS_ROLLING_MEASURE];
int cur_obs_idx; /**< Current position in obs. */
time_t cur_obs_time; /**< Time represented in obs[cur_obs_idx] */
uint64_t total_obs; /**< Total for all members of obs except
* obs[cur_obs_idx] */
uint64_t max_total; /**< Largest value that total_obs has taken on in the
* current period. */
uint64_t total_in_period; /**< Total bytes transferred in the current
* period. */
/** When does the next period begin? */
time_t next_period;
/** Where in 'maxima' should the maximum bandwidth usage for the current
* period be stored? */
int next_max_idx;
/** How many values in maxima/totals have been set ever? */
int num_maxes_set;
/** Circular array of the maximum
* bandwidth-per-NUM_SECS_ROLLING_MEASURE usage for the last
* NUM_TOTALS periods */
uint64_t maxima[NUM_TOTALS];
/** Circular array of the total bandwidth usage for the last NUM_TOTALS
* periods */
uint64_t totals[NUM_TOTALS];
} bw_array_t;
/** Shift the current period of b forward by one. */
static void
commit_max(bw_array_t *b)
{
/* Store total from current period. */
b->totals[b->next_max_idx] = b->total_in_period;
/* Store maximum from current period. */
b->maxima[b->next_max_idx++] = b->max_total;
/* Advance next_period and next_max_idx */
b->next_period += NUM_SECS_BW_SUM_INTERVAL;
if (b->next_max_idx == NUM_TOTALS)
b->next_max_idx = 0;
if (b->num_maxes_set < NUM_TOTALS)
++b->num_maxes_set;
/* Reset max_total. */
b->max_total = 0;
/* Reset total_in_period. */
b->total_in_period = 0;
}
/** Shift the current observation time of b forward by one second. */
static INLINE void
advance_obs(bw_array_t *b)
{
int nextidx;
uint64_t total;
/* Calculate the total bandwidth for the last NUM_SECS_ROLLING_MEASURE
* seconds; adjust max_total as needed.*/
total = b->total_obs + b->obs[b->cur_obs_idx];
if (total > b->max_total)
b->max_total = total;
nextidx = b->cur_obs_idx+1;
if (nextidx == NUM_SECS_ROLLING_MEASURE)
nextidx = 0;
b->total_obs = total - b->obs[nextidx];
b->obs[nextidx]=0;
b->cur_obs_idx = nextidx;
if (++b->cur_obs_time >= b->next_period)
commit_max(b);
}
/** Add n bytes to the number of bytes in b for second
* when. */
static INLINE void
add_obs(bw_array_t *b, time_t when, uint64_t n)
{
if (when < b->cur_obs_time)
return; /* Don't record data in the past. */
/* If we're currently adding observations for an earlier second than
* 'when', advance b->cur_obs_time and b->cur_obs_idx by an
* appropriate number of seconds, and do all the other housekeeping. */
while (when > b->cur_obs_time) {
/* Doing this one second at a time is potentially inefficient, if we start
with a state file that is very old. Fortunately, it doesn't seem to
show up in profiles, so we can just ignore it for now. */
advance_obs(b);
}
b->obs[b->cur_obs_idx] += n;
b->total_in_period += n;
}
/** Allocate, initialize, and return a new bw_array. */
static bw_array_t *
bw_array_new(void)
{
bw_array_t *b;
time_t start;
b = tor_malloc_zero(sizeof(bw_array_t));
rephist_total_alloc += sizeof(bw_array_t);
start = time(NULL);
b->cur_obs_time = start;
b->next_period = start + NUM_SECS_BW_SUM_INTERVAL;
return b;
}
/** Recent history of bandwidth observations for read operations. */
static bw_array_t *read_array = NULL;
/** Recent history of bandwidth observations for write operations. */
static bw_array_t *write_array = NULL;
/** Recent history of bandwidth observations for read operations for the
directory protocol. */
static bw_array_t *dir_read_array = NULL;
/** Recent history of bandwidth observations for write operations for the
directory protocol. */
static bw_array_t *dir_write_array = NULL;
/** Set up [dir-]read_array and [dir-]write_array, freeing them if they
* already exist. */
static void
bw_arrays_init(void)
{
tor_free(read_array);
tor_free(write_array);
tor_free(dir_read_array);
tor_free(dir_write_array);
read_array = bw_array_new();
write_array = bw_array_new();
dir_read_array = bw_array_new();
dir_write_array = bw_array_new();
}
/** Remember that we read num_bytes bytes in second when.
*
* Add num_bytes to the current running total for when.
*
* when can go back to time, but it's safe to ignore calls
* earlier than the latest when you've heard of.
*/
void
rep_hist_note_bytes_written(size_t num_bytes, time_t when)
{
/* Maybe a circular array for recent seconds, and step to a new point
* every time a new second shows up. Or simpler is to just to have
* a normal array and push down each item every second; it's short.
*/
/* When a new second has rolled over, compute the sum of the bytes we've
* seen over when-1 to when-1-NUM_SECS_ROLLING_MEASURE, and stick it
* somewhere. See rep_hist_bandwidth_assess() below.
*/
add_obs(write_array, when, num_bytes);
}
/** Remember that we wrote num_bytes bytes in second when.
* (like rep_hist_note_bytes_written() above)
*/
void
rep_hist_note_bytes_read(size_t num_bytes, time_t when)
{
/* if we're smart, we can make this func and the one above share code */
add_obs(read_array, when, num_bytes);
}
/** Remember that we wrote num_bytes directory bytes in second
* when. (like rep_hist_note_bytes_written() above)
*/
void
rep_hist_note_dir_bytes_written(size_t num_bytes, time_t when)
{
add_obs(dir_write_array, when, num_bytes);
}
/** Remember that we read num_bytes directory bytes in second
* when. (like rep_hist_note_bytes_written() above)
*/
void
rep_hist_note_dir_bytes_read(size_t num_bytes, time_t when)
{
add_obs(dir_read_array, when, num_bytes);
}
/** Helper: Return the largest value in b->maxima. (This is equal to the
* most bandwidth used in any NUM_SECS_ROLLING_MEASURE period for the last
* NUM_SECS_BW_SUM_IS_VALID seconds.)
*/
static uint64_t
find_largest_max(bw_array_t *b)
{
int i;
uint64_t max;
max=0;
for (i=0; imaxima[i]>max)
max = b->maxima[i];
}
return max;
}
/** Find the largest sums in the past NUM_SECS_BW_SUM_IS_VALID (roughly)
* seconds. Find one sum for reading and one for writing. They don't have
* to be at the same time.
*
* Return the smaller of these sums, divided by NUM_SECS_ROLLING_MEASURE.
*/
int
rep_hist_bandwidth_assess(void)
{
uint64_t w,r;
r = find_largest_max(read_array);
w = find_largest_max(write_array);
if (r>w)
return (int)(U64_TO_DBL(w)/NUM_SECS_ROLLING_MEASURE);
else
return (int)(U64_TO_DBL(r)/NUM_SECS_ROLLING_MEASURE);
}
/** Print the bandwidth history of b (either [dir-]read_array or
* [dir-]write_array) into the buffer pointed to by buf. The format is
* simply comma separated numbers, from oldest to newest.
*
* It returns the number of bytes written.
*/
static size_t
rep_hist_fill_bandwidth_history(char *buf, size_t len, const bw_array_t *b)
{
char *cp = buf;
int i, n;
const or_options_t *options = get_options();
uint64_t cutoff;
if (b->num_maxes_set <= b->next_max_idx) {
/* We haven't been through the circular array yet; time starts at i=0.*/
i = 0;
} else {
/* We've been around the array at least once. The next i to be
overwritten is the oldest. */
i = b->next_max_idx;
}
if (options->RelayBandwidthRate) {
/* We don't want to report that we used more bandwidth than the max we're
* willing to relay; otherwise everybody will know how much traffic
* we used ourself. */
cutoff = options->RelayBandwidthRate * NUM_SECS_BW_SUM_INTERVAL;
} else {
cutoff = UINT64_MAX;
}
for (n=0; nnum_maxes_set; ++n,++i) {
uint64_t total;
if (i >= NUM_TOTALS)
i -= NUM_TOTALS;
tor_assert(i < NUM_TOTALS);
/* Round the bandwidth used down to the nearest 1k. */
total = b->totals[i] & ~0x3ff;
if (total > cutoff)
total = cutoff;
if (n==(b->num_maxes_set-1))
tor_snprintf(cp, len-(cp-buf), U64_FORMAT, U64_PRINTF_ARG(total));
else
tor_snprintf(cp, len-(cp-buf), U64_FORMAT",", U64_PRINTF_ARG(total));
cp += strlen(cp);
}
return cp-buf;
}
/** Allocate and return lines for representing this server's bandwidth
* history in its descriptor. We publish these lines in our extra-info
* descriptor.
*/
char *
rep_hist_get_bandwidth_lines(void)
{
char *buf, *cp;
char t[ISO_TIME_LEN+1];
int r;
bw_array_t *b = NULL;
const char *desc = NULL;
size_t len;
/* opt [dirreq-](read|write)-history yyyy-mm-dd HH:MM:SS (n s) n,n,n... */
/* The n,n,n part above. Largest representation of a uint64_t is 20 chars
* long, plus the comma. */
#define MAX_HIST_VALUE_LEN 21*NUM_TOTALS
len = (67+MAX_HIST_VALUE_LEN)*4;
buf = tor_malloc_zero(len);
cp = buf;
for (r=0;r<4;++r) {
char tmp[MAX_HIST_VALUE_LEN];
size_t slen;
switch (r) {
case 0:
b = write_array;
desc = "write-history";
break;
case 1:
b = read_array;
desc = "read-history";
break;
case 2:
b = dir_write_array;
desc = "dirreq-write-history";
break;
case 3:
b = dir_read_array;
desc = "dirreq-read-history";
break;
}
tor_assert(b);
slen = rep_hist_fill_bandwidth_history(tmp, MAX_HIST_VALUE_LEN, b);
/* If we don't have anything to write, skip to the next entry. */
if (slen == 0)
continue;
format_iso_time(t, b->next_period-NUM_SECS_BW_SUM_INTERVAL);
tor_snprintf(cp, len-(cp-buf), "%s %s (%d s) ",
desc, t, NUM_SECS_BW_SUM_INTERVAL);
cp += strlen(cp);
strlcat(cp, tmp, len-(cp-buf));
cp += slen;
strlcat(cp, "\n", len-(cp-buf));
++cp;
}
return buf;
}
/** Write a single bw_array_t into the Values, Ends, Interval, and Maximum
* entries of an or_state_t. Done before writing out a new state file. */
static void
rep_hist_update_bwhist_state_section(or_state_t *state,
const bw_array_t *b,
smartlist_t **s_values,
smartlist_t **s_maxima,
time_t *s_begins,
int *s_interval)
{
int i,j;
uint64_t maxval;
if (*s_values) {
SMARTLIST_FOREACH(*s_values, char *, val, tor_free(val));
smartlist_free(*s_values);
}
if (*s_maxima) {
SMARTLIST_FOREACH(*s_maxima, char *, val, tor_free(val));
smartlist_free(*s_maxima);
}
if (! server_mode(get_options())) {
/* Clients don't need to store bandwidth history persistently;
* force these values to the defaults. */
/* FFFF we should pull the default out of config.c's state table,
* so we don't have two defaults. */
if (*s_begins != 0 || *s_interval != 900) {
time_t now = time(NULL);
time_t save_at = get_options()->AvoidDiskWrites ? now+3600 : now+600;
or_state_mark_dirty(state, save_at);
}
*s_begins = 0;
*s_interval = 900;
*s_values = smartlist_new();
*s_maxima = smartlist_new();
return;
}
*s_begins = b->next_period;
*s_interval = NUM_SECS_BW_SUM_INTERVAL;
*s_values = smartlist_new();
*s_maxima = smartlist_new();
/* Set i to first position in circular array */
i = (b->num_maxes_set <= b->next_max_idx) ? 0 : b->next_max_idx;
for (j=0; j < b->num_maxes_set; ++j,++i) {
if (i >= NUM_TOTALS)
i = 0;
smartlist_add_asprintf(*s_values, U64_FORMAT,
U64_PRINTF_ARG(b->totals[i] & ~0x3ff));
maxval = b->maxima[i] / NUM_SECS_ROLLING_MEASURE;
smartlist_add_asprintf(*s_maxima, U64_FORMAT,
U64_PRINTF_ARG(maxval & ~0x3ff));
}
smartlist_add_asprintf(*s_values, U64_FORMAT,
U64_PRINTF_ARG(b->total_in_period & ~0x3ff));
maxval = b->max_total / NUM_SECS_ROLLING_MEASURE;
smartlist_add_asprintf(*s_maxima, U64_FORMAT,
U64_PRINTF_ARG(maxval & ~0x3ff));
}
/** Update state with the newest bandwidth history. Done before
* writing out a new state file. */
void
rep_hist_update_state(or_state_t *state)
{
#define UPDATE(arrname,st) \
rep_hist_update_bwhist_state_section(state,\
(arrname),\
&state->BWHistory ## st ## Values, \
&state->BWHistory ## st ## Maxima, \
&state->BWHistory ## st ## Ends, \
&state->BWHistory ## st ## Interval)
UPDATE(write_array, Write);
UPDATE(read_array, Read);
UPDATE(dir_write_array, DirWrite);
UPDATE(dir_read_array, DirRead);
if (server_mode(get_options())) {
or_state_mark_dirty(state, time(NULL)+(2*3600));
}
#undef UPDATE
}
/** Load a single bw_array_t from its Values, Ends, Maxima, and Interval
* entries in an or_state_t. Done while reading the state file. */
static int
rep_hist_load_bwhist_state_section(bw_array_t *b,
const smartlist_t *s_values,
const smartlist_t *s_maxima,
const time_t s_begins,
const int s_interval)
{
time_t now = time(NULL);
int retval = 0;
time_t start;
uint64_t v, mv;
int i,ok,ok_m;
int have_maxima = (smartlist_len(s_values) == smartlist_len(s_maxima));
if (s_values && s_begins >= now - NUM_SECS_BW_SUM_INTERVAL*NUM_TOTALS) {
start = s_begins - s_interval*(smartlist_len(s_values));
if (start > now)
return 0;
b->cur_obs_time = start;
b->next_period = start + NUM_SECS_BW_SUM_INTERVAL;
SMARTLIST_FOREACH_BEGIN(s_values, const char *, cp) {
const char *maxstr = NULL;
v = tor_parse_uint64(cp, 10, 0, UINT64_MAX, &ok, NULL);
if (have_maxima) {
maxstr = smartlist_get(s_maxima, cp_sl_idx);
mv = tor_parse_uint64(maxstr, 10, 0, UINT64_MAX, &ok_m, NULL);
mv *= NUM_SECS_ROLLING_MEASURE;
} else {
/* No maxima known; guess average rate to be conservative. */
mv = (v / s_interval) * NUM_SECS_ROLLING_MEASURE;
}
if (!ok) {
retval = -1;
log_notice(LD_HIST, "Could not parse value '%s' into a number.'",cp);
}
if (maxstr && !ok_m) {
retval = -1;
log_notice(LD_HIST, "Could not parse maximum '%s' into a number.'",
maxstr);
}
if (start < now) {
time_t cur_start = start;
time_t actual_interval_len = s_interval;
uint64_t cur_val = 0;
/* Calculate the average per second. This is the best we can do
* because our state file doesn't have per-second resolution. */
if (start + s_interval > now)
actual_interval_len = now - start;
cur_val = v / actual_interval_len;
/* This is potentially inefficient, but since we don't do it very
* often it should be ok. */
while (cur_start < start + actual_interval_len) {
add_obs(b, cur_start, cur_val);
++cur_start;
}
b->max_total = mv;
/* This will result in some fairly choppy history if s_interval
* is not the same as NUM_SECS_BW_SUM_INTERVAL. XXXX */
start += actual_interval_len;
}
} SMARTLIST_FOREACH_END(cp);
}
/* Clean up maxima and observed */
for (i=0; iobs[i] = 0;
}
b->total_obs = 0;
return retval;
}
/** Set bandwidth history from the state file we just loaded. */
int
rep_hist_load_state(or_state_t *state, char **err)
{
int all_ok = 1;
/* Assert they already have been malloced */
tor_assert(read_array && write_array);
tor_assert(dir_read_array && dir_write_array);
#define LOAD(arrname,st) \
if (rep_hist_load_bwhist_state_section( \
(arrname), \
state->BWHistory ## st ## Values, \
state->BWHistory ## st ## Maxima, \
state->BWHistory ## st ## Ends, \
state->BWHistory ## st ## Interval)<0) \
all_ok = 0
LOAD(write_array, Write);
LOAD(read_array, Read);
LOAD(dir_write_array, DirWrite);
LOAD(dir_read_array, DirRead);
#undef LOAD
if (!all_ok) {
*err = tor_strdup("Parsing of bandwidth history values failed");
/* and create fresh arrays */
bw_arrays_init();
return -1;
}
return 0;
}
/*********************************************************************/
/** A single predicted port: used to remember which ports we've made
* connections to, so that we can try to keep making circuits that can handle
* those ports. */
typedef struct predicted_port_t {
/** The port we connected to */
uint16_t port;
/** The time at which we last used it */
time_t time;
} predicted_port_t;
/** A list of port numbers that have been used recently. */
static smartlist_t *predicted_ports_list=NULL;
/** We just got an application request for a connection with
* port port. Remember it for the future, so we can keep
* some circuits open that will exit to this port.
*/
static void
add_predicted_port(time_t now, uint16_t port)
{
predicted_port_t *pp = tor_malloc(sizeof(predicted_port_t));
pp->port = port;
pp->time = now;
rephist_total_alloc += sizeof(*pp);
smartlist_add(predicted_ports_list, pp);
}
/** Initialize whatever memory and structs are needed for predicting
* which ports will be used. Also seed it with port 80, so we'll build
* circuits on start-up.
*/
static void
predicted_ports_init(void)
{
predicted_ports_list = smartlist_new();
add_predicted_port(time(NULL), 80); /* add one to kickstart us */
}
/** Free whatever memory is needed for predicting which ports will
* be used.
*/
static void
predicted_ports_free(void)
{
rephist_total_alloc -=
smartlist_len(predicted_ports_list)*sizeof(predicted_port_t);
SMARTLIST_FOREACH(predicted_ports_list, predicted_port_t *,
pp, tor_free(pp));
smartlist_free(predicted_ports_list);
}
/** Remember that port has been asked for as of time now.
* This is used for predicting what sorts of streams we'll make in the
* future and making exit circuits to anticipate that.
*/
void
rep_hist_note_used_port(time_t now, uint16_t port)
{
tor_assert(predicted_ports_list);
if (!port) /* record nothing */
return;
SMARTLIST_FOREACH_BEGIN(predicted_ports_list, predicted_port_t *, pp) {
if (pp->port == port) {
pp->time = now;
return;
}
} SMARTLIST_FOREACH_END(pp);
/* it's not there yet; we need to add it */
add_predicted_port(now, port);
}
/** For this long after we've seen a request for a given port, assume that
* we'll want to make connections to the same port in the future. */
#define PREDICTED_CIRCS_RELEVANCE_TIME (60*60)
/** Return a newly allocated pointer to a list of uint16_t * for ports that
* are likely to be asked for in the near future.
*/
smartlist_t *
rep_hist_get_predicted_ports(time_t now)
{
smartlist_t *out = smartlist_new();
tor_assert(predicted_ports_list);
/* clean out obsolete entries */
SMARTLIST_FOREACH_BEGIN(predicted_ports_list, predicted_port_t *, pp) {
if (pp->time + PREDICTED_CIRCS_RELEVANCE_TIME < now) {
log_debug(LD_CIRC, "Expiring predicted port %d", pp->port);
rephist_total_alloc -= sizeof(predicted_port_t);
tor_free(pp);
SMARTLIST_DEL_CURRENT(predicted_ports_list, pp);
} else {
smartlist_add(out, tor_memdup(&pp->port, sizeof(uint16_t)));
}
} SMARTLIST_FOREACH_END(pp);
return out;
}
/**
* Take a list of uint16_t *, and remove every port in the list from the
* current list of predicted ports.
*/
void
rep_hist_remove_predicted_ports(const smartlist_t *rmv_ports)
{
/* Let's do this on O(N), not O(N^2). */
bitarray_t *remove_ports = bitarray_init_zero(UINT16_MAX);
SMARTLIST_FOREACH(rmv_ports, const uint16_t *, p,
bitarray_set(remove_ports, *p));
SMARTLIST_FOREACH_BEGIN(predicted_ports_list, predicted_port_t *, pp) {
if (bitarray_is_set(remove_ports, pp->port)) {
tor_free(pp);
SMARTLIST_DEL_CURRENT(predicted_ports_list, pp);
}
} SMARTLIST_FOREACH_END(pp);
bitarray_free(remove_ports);
}
/** The user asked us to do a resolve. Rather than keeping track of
* timings and such of resolves, we fake it for now by treating
* it the same way as a connection to port 80. This way we will continue
* to have circuits lying around if the user only uses Tor for resolves.
*/
void
rep_hist_note_used_resolve(time_t now)
{
rep_hist_note_used_port(now, 80);
}
/** The last time at which we needed an internal circ. */
static time_t predicted_internal_time = 0;
/** The last time we needed an internal circ with good uptime. */
static time_t predicted_internal_uptime_time = 0;
/** The last time we needed an internal circ with good capacity. */
static time_t predicted_internal_capacity_time = 0;
/** Remember that we used an internal circ at time now. */
void
rep_hist_note_used_internal(time_t now, int need_uptime, int need_capacity)
{
predicted_internal_time = now;
if (need_uptime)
predicted_internal_uptime_time = now;
if (need_capacity)
predicted_internal_capacity_time = now;
}
/** Return 1 if we've used an internal circ recently; else return 0. */
int
rep_hist_get_predicted_internal(time_t now, int *need_uptime,
int *need_capacity)
{
if (!predicted_internal_time) { /* initialize it */
predicted_internal_time = now;
predicted_internal_uptime_time = now;
predicted_internal_capacity_time = now;
}
if (predicted_internal_time + PREDICTED_CIRCS_RELEVANCE_TIME < now)
return 0; /* too long ago */
if (predicted_internal_uptime_time + PREDICTED_CIRCS_RELEVANCE_TIME >= now)
*need_uptime = 1;
// Always predict that we need capacity.
*need_capacity = 1;
return 1;
}
/** Any ports used lately? These are pre-seeded if we just started
* up or if we're running a hidden service. */
int
any_predicted_circuits(time_t now)
{
return smartlist_len(predicted_ports_list) ||
predicted_internal_time + PREDICTED_CIRCS_RELEVANCE_TIME >= now;
}
/** Return 1 if we have no need for circuits currently, else return 0. */
int
rep_hist_circbuilding_dormant(time_t now)
{
if (any_predicted_circuits(now))
return 0;
/* see if we'll still need to build testing circuits */
if (server_mode(get_options()) &&
(!check_whether_orport_reachable() || !circuit_enough_testing_circs()))
return 0;
if (!check_whether_dirport_reachable())
return 0;
return 1;
}
/** Structure to track how many times we've done each public key operation. */
static struct {
/** How many directory objects have we signed? */
unsigned long n_signed_dir_objs;
/** How many routerdescs have we signed? */
unsigned long n_signed_routerdescs;
/** How many directory objects have we verified? */
unsigned long n_verified_dir_objs;
/** How many routerdescs have we verified */
unsigned long n_verified_routerdescs;
/** How many onionskins have we encrypted to build circuits? */
unsigned long n_onionskins_encrypted;
/** How many onionskins have we decrypted to do circuit build requests? */
unsigned long n_onionskins_decrypted;
/** How many times have we done the TLS handshake as a client? */
unsigned long n_tls_client_handshakes;
/** How many times have we done the TLS handshake as a server? */
unsigned long n_tls_server_handshakes;
/** How many PK operations have we done as a hidden service client? */
unsigned long n_rend_client_ops;
/** How many PK operations have we done as a hidden service midpoint? */
unsigned long n_rend_mid_ops;
/** How many PK operations have we done as a hidden service provider? */
unsigned long n_rend_server_ops;
} pk_op_counts = {0,0,0,0,0,0,0,0,0,0,0};
/** Increment the count of the number of times we've done operation. */
void
note_crypto_pk_op(pk_op_t operation)
{
switch (operation)
{
case SIGN_DIR:
pk_op_counts.n_signed_dir_objs++;
break;
case SIGN_RTR:
pk_op_counts.n_signed_routerdescs++;
break;
case VERIFY_DIR:
pk_op_counts.n_verified_dir_objs++;
break;
case VERIFY_RTR:
pk_op_counts.n_verified_routerdescs++;
break;
case ENC_ONIONSKIN:
pk_op_counts.n_onionskins_encrypted++;
break;
case DEC_ONIONSKIN:
pk_op_counts.n_onionskins_decrypted++;
break;
case TLS_HANDSHAKE_C:
pk_op_counts.n_tls_client_handshakes++;
break;
case TLS_HANDSHAKE_S:
pk_op_counts.n_tls_server_handshakes++;
break;
case REND_CLIENT:
pk_op_counts.n_rend_client_ops++;
break;
case REND_MID:
pk_op_counts.n_rend_mid_ops++;
break;
case REND_SERVER:
pk_op_counts.n_rend_server_ops++;
break;
default:
log_warn(LD_BUG, "Unknown pk operation %d", operation);
}
}
/** Log the number of times we've done each public/private-key operation. */
void
dump_pk_ops(int severity)
{
log(severity, LD_HIST,
"PK operations: %lu directory objects signed, "
"%lu directory objects verified, "
"%lu routerdescs signed, "
"%lu routerdescs verified, "
"%lu onionskins encrypted, "
"%lu onionskins decrypted, "
"%lu client-side TLS handshakes, "
"%lu server-side TLS handshakes, "
"%lu rendezvous client operations, "
"%lu rendezvous middle operations, "
"%lu rendezvous server operations.",
pk_op_counts.n_signed_dir_objs,
pk_op_counts.n_verified_dir_objs,
pk_op_counts.n_signed_routerdescs,
pk_op_counts.n_verified_routerdescs,
pk_op_counts.n_onionskins_encrypted,
pk_op_counts.n_onionskins_decrypted,
pk_op_counts.n_tls_client_handshakes,
pk_op_counts.n_tls_server_handshakes,
pk_op_counts.n_rend_client_ops,
pk_op_counts.n_rend_mid_ops,
pk_op_counts.n_rend_server_ops);
}
/*** Exit port statistics ***/
/* Some constants */
/** To what multiple should byte numbers be rounded up? */
#define EXIT_STATS_ROUND_UP_BYTES 1024
/** To what multiple should stream counts be rounded up? */
#define EXIT_STATS_ROUND_UP_STREAMS 4
/** Number of TCP ports */
#define EXIT_STATS_NUM_PORTS 65536
/** Top n ports that will be included in exit stats. */
#define EXIT_STATS_TOP_N_PORTS 10
/* The following data structures are arrays and no fancy smartlists or maps,
* so that all write operations can be done in constant time. This comes at
* the price of some memory (1.25 MB) and linear complexity when writing
* stats for measuring relays. */
/** Number of bytes read in current period by exit port */
static uint64_t *exit_bytes_read = NULL;
/** Number of bytes written in current period by exit port */
static uint64_t *exit_bytes_written = NULL;
/** Number of streams opened in current period by exit port */
static uint32_t *exit_streams = NULL;
/** Start time of exit stats or 0 if we're not collecting exit stats. */
static time_t start_of_exit_stats_interval;
/** Initialize exit port stats. */
void
rep_hist_exit_stats_init(time_t now)
{
start_of_exit_stats_interval = now;
exit_bytes_read = tor_malloc_zero(EXIT_STATS_NUM_PORTS *
sizeof(uint64_t));
exit_bytes_written = tor_malloc_zero(EXIT_STATS_NUM_PORTS *
sizeof(uint64_t));
exit_streams = tor_malloc_zero(EXIT_STATS_NUM_PORTS *
sizeof(uint32_t));
}
/** Reset counters for exit port statistics. */
void
rep_hist_reset_exit_stats(time_t now)
{
start_of_exit_stats_interval = now;
memset(exit_bytes_read, 0, EXIT_STATS_NUM_PORTS * sizeof(uint64_t));
memset(exit_bytes_written, 0, EXIT_STATS_NUM_PORTS * sizeof(uint64_t));
memset(exit_streams, 0, EXIT_STATS_NUM_PORTS * sizeof(uint32_t));
}
/** Stop collecting exit port stats in a way that we can re-start doing
* so in rep_hist_exit_stats_init(). */
void
rep_hist_exit_stats_term(void)
{
start_of_exit_stats_interval = 0;
tor_free(exit_bytes_read);
tor_free(exit_bytes_written);
tor_free(exit_streams);
}
/** Helper for qsort: compare two ints. Does not handle overflow properly,
* but works fine for sorting an array of port numbers, which is what we use
* it for. */
static int
_compare_int(const void *x, const void *y)
{
return (*(int*)x - *(int*)y);
}
/** Return a newly allocated string containing the exit port statistics
* until now, or NULL if we're not collecting exit stats. Caller
* must ensure start_of_exit_stats_interval is in the past. */
char *
rep_hist_format_exit_stats(time_t now)
{
int i, j, top_elements = 0, cur_min_idx = 0, cur_port;
uint64_t top_bytes[EXIT_STATS_TOP_N_PORTS];
int top_ports[EXIT_STATS_TOP_N_PORTS];
uint64_t cur_bytes = 0, other_read = 0, other_written = 0,
total_read = 0, total_written = 0;
uint32_t total_streams = 0, other_streams = 0;
smartlist_t *written_strings, *read_strings, *streams_strings;
char *written_string, *read_string, *streams_string;
char t[ISO_TIME_LEN+1];
char *result;
if (!start_of_exit_stats_interval)
return NULL; /* Not initialized. */
tor_assert(now >= start_of_exit_stats_interval);
/* Go through all ports to find the n ports that saw most written and
* read bytes.
*
* Invariant: at the end of the loop for iteration i,
* total_read is the sum of all exit_bytes_read[0..i]
* total_written is the sum of all exit_bytes_written[0..i]
* total_stream is the sum of all exit_streams[0..i]
*
* top_elements = MAX(EXIT_STATS_TOP_N_PORTS,
* #{j | 0 <= j <= i && volume(i) > 0})
*
* For all 0 <= j < top_elements,
* top_bytes[j] > 0
* 0 <= top_ports[j] <= 65535
* top_bytes[j] = volume(top_ports[j])
*
* There is no j in 0..i and k in 0..top_elements such that:
* volume(j) > top_bytes[k] AND j is not in top_ports[0..top_elements]
*
* There is no j!=cur_min_idx in 0..top_elements such that:
* top_bytes[j] < top_bytes[cur_min_idx]
*
* where volume(x) == exit_bytes_read[x]+exit_bytes_written[x]
*
* Worst case: O(EXIT_STATS_NUM_PORTS * EXIT_STATS_TOP_N_PORTS)
*/
for (i = 1; i < EXIT_STATS_NUM_PORTS; i++) {
total_read += exit_bytes_read[i];
total_written += exit_bytes_written[i];
total_streams += exit_streams[i];
cur_bytes = exit_bytes_read[i] + exit_bytes_written[i];
if (cur_bytes == 0) {
continue;
}
if (top_elements < EXIT_STATS_TOP_N_PORTS) {
top_bytes[top_elements] = cur_bytes;
top_ports[top_elements++] = i;
} else if (cur_bytes > top_bytes[cur_min_idx]) {
top_bytes[cur_min_idx] = cur_bytes;
top_ports[cur_min_idx] = i;
} else {
continue;
}
cur_min_idx = 0;
for (j = 1; j < top_elements; j++) {
if (top_bytes[j] < top_bytes[cur_min_idx]) {
cur_min_idx = j;
}
}
}
/* Add observations of top ports to smartlists. */
written_strings = smartlist_new();
read_strings = smartlist_new();
streams_strings = smartlist_new();
other_read = total_read;
other_written = total_written;
other_streams = total_streams;
/* Sort the ports; this puts them out of sync with top_bytes, but we
* won't be using top_bytes again anyway */
qsort(top_ports, top_elements, sizeof(int), _compare_int);
for (j = 0; j < top_elements; j++) {
cur_port = top_ports[j];
if (exit_bytes_written[cur_port] > 0) {
uint64_t num = round_uint64_to_next_multiple_of(
exit_bytes_written[cur_port],
EXIT_STATS_ROUND_UP_BYTES);
num /= 1024;
smartlist_add_asprintf(written_strings, "%d="U64_FORMAT,
cur_port, U64_PRINTF_ARG(num));
other_written -= exit_bytes_written[cur_port];
}
if (exit_bytes_read[cur_port] > 0) {
uint64_t num = round_uint64_to_next_multiple_of(
exit_bytes_read[cur_port],
EXIT_STATS_ROUND_UP_BYTES);
num /= 1024;
smartlist_add_asprintf(read_strings, "%d="U64_FORMAT,
cur_port, U64_PRINTF_ARG(num));
other_read -= exit_bytes_read[cur_port];
}
if (exit_streams[cur_port] > 0) {
uint32_t num = round_uint32_to_next_multiple_of(
exit_streams[cur_port],
EXIT_STATS_ROUND_UP_STREAMS);
smartlist_add_asprintf(streams_strings, "%d=%u", cur_port, num);
other_streams -= exit_streams[cur_port];
}
}
/* Add observations of other ports in a single element. */
other_written = round_uint64_to_next_multiple_of(other_written,
EXIT_STATS_ROUND_UP_BYTES);
other_written /= 1024;
smartlist_add_asprintf(written_strings, "other="U64_FORMAT,
U64_PRINTF_ARG(other_written));
other_read = round_uint64_to_next_multiple_of(other_read,
EXIT_STATS_ROUND_UP_BYTES);
other_read /= 1024;
smartlist_add_asprintf(read_strings, "other="U64_FORMAT,
U64_PRINTF_ARG(other_read));
other_streams = round_uint32_to_next_multiple_of(other_streams,
EXIT_STATS_ROUND_UP_STREAMS);
smartlist_add_asprintf(streams_strings, "other=%u", other_streams);
/* Join all observations in single strings. */
written_string = smartlist_join_strings(written_strings, ",", 0, NULL);
read_string = smartlist_join_strings(read_strings, ",", 0, NULL);
streams_string = smartlist_join_strings(streams_strings, ",", 0, NULL);
SMARTLIST_FOREACH(written_strings, char *, cp, tor_free(cp));
SMARTLIST_FOREACH(read_strings, char *, cp, tor_free(cp));
SMARTLIST_FOREACH(streams_strings, char *, cp, tor_free(cp));
smartlist_free(written_strings);
smartlist_free(read_strings);
smartlist_free(streams_strings);
/* Put everything together. */
format_iso_time(t, now);
tor_asprintf(&result, "exit-stats-end %s (%d s)\n"
"exit-kibibytes-written %s\n"
"exit-kibibytes-read %s\n"
"exit-streams-opened %s\n",
t, (unsigned) (now - start_of_exit_stats_interval),
written_string,
read_string,
streams_string);
tor_free(written_string);
tor_free(read_string);
tor_free(streams_string);
return result;
}
/** If 24 hours have passed since the beginning of the current exit port
* stats period, write exit stats to $DATADIR/stats/exit-stats (possibly
* overwriting an existing file) and reset counters. Return when we would
* next want to write exit stats or 0 if we never want to write. */
time_t
rep_hist_exit_stats_write(time_t now)
{
char *statsdir = NULL, *filename = NULL, *str = NULL;
if (!start_of_exit_stats_interval)
return 0; /* Not initialized. */
if (start_of_exit_stats_interval + WRITE_STATS_INTERVAL > now)
goto done; /* Not ready to write. */
log_info(LD_HIST, "Writing exit port statistics to disk.");
/* Generate history string. */
str = rep_hist_format_exit_stats(now);
/* Reset counters. */
rep_hist_reset_exit_stats(now);
/* Try to write to disk. */
statsdir = get_datadir_fname("stats");
if (check_private_dir(statsdir, CPD_CREATE, get_options()->User) < 0) {
log_warn(LD_HIST, "Unable to create stats/ directory!");
goto done;
}
filename = get_datadir_fname2("stats", "exit-stats");
if (write_str_to_file(filename, str, 0) < 0)
log_warn(LD_HIST, "Unable to write exit port statistics to disk!");
done:
tor_free(str);
tor_free(statsdir);
tor_free(filename);
return start_of_exit_stats_interval + WRITE_STATS_INTERVAL;
}
/** Note that we wrote num_written bytes and read num_read
* bytes to/from an exit connection to port. */
void
rep_hist_note_exit_bytes(uint16_t port, size_t num_written,
size_t num_read)
{
if (!start_of_exit_stats_interval)
return; /* Not initialized. */
exit_bytes_written[port] += num_written;
exit_bytes_read[port] += num_read;
log_debug(LD_HIST, "Written %lu bytes and read %lu bytes to/from an "
"exit connection to port %d.",
(unsigned long)num_written, (unsigned long)num_read, port);
}
/** Note that we opened an exit stream to port. */
void
rep_hist_note_exit_stream_opened(uint16_t port)
{
if (!start_of_exit_stats_interval)
return; /* Not initialized. */
exit_streams[port]++;
log_debug(LD_HIST, "Opened exit stream to port %d", port);
}
/*** cell statistics ***/
/** Start of the current buffer stats interval or 0 if we're not
* collecting buffer statistics. */
static time_t start_of_buffer_stats_interval;
/** Initialize buffer stats. */
void
rep_hist_buffer_stats_init(time_t now)
{
start_of_buffer_stats_interval = now;
}
/** Statistics from a single circuit. Collected when the circuit closes, or
* when we flush statistics to disk. */
typedef struct circ_buffer_stats_t {
/** Average number of cells in the circuit's queue */
double mean_num_cells_in_queue;
/** Average time a cell waits in the queue. */
double mean_time_cells_in_queue;
/** Total number of cells sent over this circuit */
uint32_t processed_cells;
} circ_buffer_stats_t;
/** List of circ_buffer_stats_t. */
static smartlist_t *circuits_for_buffer_stats = NULL;
/** Remember cell statistics mean_num_cells_in_queue,
* mean_time_cells_in_queue, and processed_cells of a
* circuit. */
void
rep_hist_add_buffer_stats(double mean_num_cells_in_queue,
double mean_time_cells_in_queue, uint32_t processed_cells)
{
circ_buffer_stats_t *stat;
if (!start_of_buffer_stats_interval)
return; /* Not initialized. */
stat = tor_malloc_zero(sizeof(circ_buffer_stats_t));
stat->mean_num_cells_in_queue = mean_num_cells_in_queue;
stat->mean_time_cells_in_queue = mean_time_cells_in_queue;
stat->processed_cells = processed_cells;
if (!circuits_for_buffer_stats)
circuits_for_buffer_stats = smartlist_new();
smartlist_add(circuits_for_buffer_stats, stat);
}
/** Remember cell statistics for circuit circ at time
* end_of_interval and reset cell counters in case the circuit
* remains open in the next measurement interval. */
void
rep_hist_buffer_stats_add_circ(circuit_t *circ, time_t end_of_interval)
{
time_t start_of_interval;
int interval_length;
or_circuit_t *orcirc;
double mean_num_cells_in_queue, mean_time_cells_in_queue;
uint32_t processed_cells;
if (CIRCUIT_IS_ORIGIN(circ))
return;
orcirc = TO_OR_CIRCUIT(circ);
if (!orcirc->processed_cells)
return;
start_of_interval = (circ->timestamp_created.tv_sec >
start_of_buffer_stats_interval) ?
circ->timestamp_created.tv_sec :
start_of_buffer_stats_interval;
interval_length = (int) (end_of_interval - start_of_interval);
if (interval_length <= 0)
return;
processed_cells = orcirc->processed_cells;
/* 1000.0 for s -> ms; 2.0 because of app-ward and exit-ward queues */
mean_num_cells_in_queue = (double) orcirc->total_cell_waiting_time /
(double) interval_length / 1000.0 / 2.0;
mean_time_cells_in_queue =
(double) orcirc->total_cell_waiting_time /
(double) orcirc->processed_cells;
orcirc->total_cell_waiting_time = 0;
orcirc->processed_cells = 0;
rep_hist_add_buffer_stats(mean_num_cells_in_queue,
mean_time_cells_in_queue,
processed_cells);
}
/** Sorting helper: return -1, 1, or 0 based on comparison of two
* circ_buffer_stats_t */
static int
_buffer_stats_compare_entries(const void **_a, const void **_b)
{
const circ_buffer_stats_t *a = *_a, *b = *_b;
if (a->processed_cells < b->processed_cells)
return 1;
else if (a->processed_cells > b->processed_cells)
return -1;
else
return 0;
}
/** Stop collecting cell stats in a way that we can re-start doing so in
* rep_hist_buffer_stats_init(). */
void
rep_hist_buffer_stats_term(void)
{
rep_hist_reset_buffer_stats(0);
}
/** Clear history of circuit statistics and set the measurement interval
* start to now. */
void
rep_hist_reset_buffer_stats(time_t now)
{
if (!circuits_for_buffer_stats)
circuits_for_buffer_stats = smartlist_new();
SMARTLIST_FOREACH(circuits_for_buffer_stats, circ_buffer_stats_t *,
stat, tor_free(stat));
smartlist_clear(circuits_for_buffer_stats);
start_of_buffer_stats_interval = now;
}
/** Return a newly allocated string containing the buffer statistics until
* now, or NULL if we're not collecting buffer stats. Caller must
* ensure start_of_buffer_stats_interval is in the past. */
char *
rep_hist_format_buffer_stats(time_t now)
{
#define SHARES 10
uint64_t processed_cells[SHARES];
uint32_t circs_in_share[SHARES];
int number_of_circuits, i;
double queued_cells[SHARES], time_in_queue[SHARES];
smartlist_t *processed_cells_strings, *queued_cells_strings,
*time_in_queue_strings;
char *processed_cells_string, *queued_cells_string,
*time_in_queue_string;
char t[ISO_TIME_LEN+1];
char *result;
if (!start_of_buffer_stats_interval)
return NULL; /* Not initialized. */
tor_assert(now >= start_of_buffer_stats_interval);
/* Calculate deciles if we saw at least one circuit. */
memset(processed_cells, 0, SHARES * sizeof(uint64_t));
memset(circs_in_share, 0, SHARES * sizeof(uint32_t));
memset(queued_cells, 0, SHARES * sizeof(double));
memset(time_in_queue, 0, SHARES * sizeof(double));
if (!circuits_for_buffer_stats)
circuits_for_buffer_stats = smartlist_new();
number_of_circuits = smartlist_len(circuits_for_buffer_stats);
if (number_of_circuits > 0) {
smartlist_sort(circuits_for_buffer_stats,
_buffer_stats_compare_entries);
i = 0;
SMARTLIST_FOREACH_BEGIN(circuits_for_buffer_stats,
circ_buffer_stats_t *, stat)
{
int share = i++ * SHARES / number_of_circuits;
processed_cells[share] += stat->processed_cells;
queued_cells[share] += stat->mean_num_cells_in_queue;
time_in_queue[share] += stat->mean_time_cells_in_queue;
circs_in_share[share]++;
}
SMARTLIST_FOREACH_END(stat);
}
/* Write deciles to strings. */
processed_cells_strings = smartlist_new();
queued_cells_strings = smartlist_new();
time_in_queue_strings = smartlist_new();
for (i = 0; i < SHARES; i++) {
smartlist_add_asprintf(processed_cells_strings,
U64_FORMAT, !circs_in_share[i] ? 0 :
U64_PRINTF_ARG(processed_cells[i] /
circs_in_share[i]));
}
for (i = 0; i < SHARES; i++) {
smartlist_add_asprintf(queued_cells_strings, "%.2f",
circs_in_share[i] == 0 ? 0.0 :
queued_cells[i] / (double) circs_in_share[i]);
}
for (i = 0; i < SHARES; i++) {
smartlist_add_asprintf(time_in_queue_strings, "%.0f",
circs_in_share[i] == 0 ? 0.0 :
time_in_queue[i] / (double) circs_in_share[i]);
}
/* Join all observations in single strings. */
processed_cells_string = smartlist_join_strings(processed_cells_strings,
",", 0, NULL);
queued_cells_string = smartlist_join_strings(queued_cells_strings,
",", 0, NULL);
time_in_queue_string = smartlist_join_strings(time_in_queue_strings,
",", 0, NULL);
SMARTLIST_FOREACH(processed_cells_strings, char *, cp, tor_free(cp));
SMARTLIST_FOREACH(queued_cells_strings, char *, cp, tor_free(cp));
SMARTLIST_FOREACH(time_in_queue_strings, char *, cp, tor_free(cp));
smartlist_free(processed_cells_strings);
smartlist_free(queued_cells_strings);
smartlist_free(time_in_queue_strings);
/* Put everything together. */
format_iso_time(t, now);
tor_asprintf(&result, "cell-stats-end %s (%d s)\n"
"cell-processed-cells %s\n"
"cell-queued-cells %s\n"
"cell-time-in-queue %s\n"
"cell-circuits-per-decile %d\n",
t, (unsigned) (now - start_of_buffer_stats_interval),
processed_cells_string,
queued_cells_string,
time_in_queue_string,
(number_of_circuits + SHARES - 1) / SHARES);
tor_free(processed_cells_string);
tor_free(queued_cells_string);
tor_free(time_in_queue_string);
return result;
#undef SHARES
}
/** If 24 hours have passed since the beginning of the current buffer
* stats period, write buffer stats to $DATADIR/stats/buffer-stats
* (possibly overwriting an existing file) and reset counters. Return
* when we would next want to write buffer stats or 0 if we never want to
* write. */
time_t
rep_hist_buffer_stats_write(time_t now)
{
circuit_t *circ;
char *statsdir = NULL, *filename = NULL, *str = NULL;
if (!start_of_buffer_stats_interval)
return 0; /* Not initialized. */
if (start_of_buffer_stats_interval + WRITE_STATS_INTERVAL > now)
goto done; /* Not ready to write */
/* Add open circuits to the history. */
for (circ = _circuit_get_global_list(); circ; circ = circ->next) {
rep_hist_buffer_stats_add_circ(circ, now);
}
/* Generate history string. */
str = rep_hist_format_buffer_stats(now);
/* Reset both buffer history and counters of open circuits. */
rep_hist_reset_buffer_stats(now);
/* Try to write to disk. */
statsdir = get_datadir_fname("stats");
if (check_private_dir(statsdir, CPD_CREATE, get_options()->User) < 0) {
log_warn(LD_HIST, "Unable to create stats/ directory!");
goto done;
}
filename = get_datadir_fname2("stats", "buffer-stats");
if (write_str_to_file(filename, str, 0) < 0)
log_warn(LD_HIST, "Unable to write buffer stats to disk!");
done:
tor_free(str);
tor_free(filename);
tor_free(statsdir);
return start_of_buffer_stats_interval + WRITE_STATS_INTERVAL;
}
/*** Descriptor serving statistics ***/
/** Digestmap to track which descriptors were downloaded this stats
* collection interval. It maps descriptor digest to pointers to 1,
* effectively turning this into a list. */
static digestmap_t *served_descs = NULL;
/** Number of how many descriptors were downloaded in total during this
* interval. */
static unsigned long total_descriptor_downloads;
/** Start time of served descs stats or 0 if we're not collecting those. */
static time_t start_of_served_descs_stats_interval;
/** Initialize descriptor stats. */
void
rep_hist_desc_stats_init(time_t now)
{
if (served_descs) {
log_warn(LD_BUG, "Called rep_hist_desc_stats_init() when desc stats were "
"already initialized. This is probably harmless.");
return; // Already initialized
}
served_descs = digestmap_new();
total_descriptor_downloads = 0;
start_of_served_descs_stats_interval = now;
}
/** Reset served descs stats to empty, starting a new interval now. */
static void
rep_hist_reset_desc_stats(time_t now)
{
rep_hist_desc_stats_term();
rep_hist_desc_stats_init(now);
}
/** Stop collecting served descs stats, so that rep_hist_desc_stats_init() is
* safe to be called again. */
void
rep_hist_desc_stats_term(void)
{
digestmap_free(served_descs, NULL);
served_descs = NULL;
start_of_served_descs_stats_interval = 0;
total_descriptor_downloads = 0;
}
/** Helper for rep_hist_desc_stats_write(). Return a newly allocated string
* containing the served desc statistics until now, or NULL if we're not
* collecting served desc stats. Caller must ensure that now is not before
* start_of_served_descs_stats_interval. */
static char *
rep_hist_format_desc_stats(time_t now)
{
char t[ISO_TIME_LEN+1];
char *result;
digestmap_iter_t *iter;
const char *key;
void *val;
unsigned size;
int *vals, max = 0, q3 = 0, md = 0, q1 = 0, min = 0;
int n = 0;
if (!start_of_served_descs_stats_interval)
return NULL;
size = digestmap_size(served_descs);
if (size > 0) {
vals = tor_malloc(size * sizeof(int));
for (iter = digestmap_iter_init(served_descs);
!digestmap_iter_done(iter);
iter = digestmap_iter_next(served_descs, iter)) {
uintptr_t count;
digestmap_iter_get(iter, &key, &val);
count = (uintptr_t)val;
vals[n++] = (int)count;
(void)key;
}
max = find_nth_int(vals, size, size-1);
q3 = find_nth_int(vals, size, (3*size-1)/4);
md = find_nth_int(vals, size, (size-1)/2);
q1 = find_nth_int(vals, size, (size-1)/4);
min = find_nth_int(vals, size, 0);
tor_free(vals);
}
format_iso_time(t, now);
tor_asprintf(&result,
"served-descs-stats-end %s (%d s) total=%lu unique=%u "
"max=%d q3=%d md=%d q1=%d min=%d\n",
t,
(unsigned) (now - start_of_served_descs_stats_interval),
total_descriptor_downloads,
size, max, q3, md, q1, min);
return result;
}
/** If WRITE_STATS_INTERVAL seconds have passed since the beginning of
* the current served desc stats interval, write the stats to
* $DATADIR/stats/served-desc-stats (possibly appending to an existing file)
* and reset the state for the next interval. Return when we would next want
* to write served desc stats or 0 if we won't want to write. */
time_t
rep_hist_desc_stats_write(time_t now)
{
char *statsdir = NULL, *filename = NULL, *str = NULL;
if (!start_of_served_descs_stats_interval)
return 0; /* We're not collecting stats. */
if (start_of_served_descs_stats_interval + WRITE_STATS_INTERVAL > now)
return start_of_served_descs_stats_interval + WRITE_STATS_INTERVAL;
str = rep_hist_format_desc_stats(now);
tor_assert(str != NULL);
statsdir = get_datadir_fname("stats");
if (check_private_dir(statsdir, CPD_CREATE, get_options()->User) < 0) {
log_warn(LD_HIST, "Unable to create stats/ directory!");
goto done;
}
filename = get_datadir_fname2("stats", "served-desc-stats");
if (append_bytes_to_file(filename, str, strlen(str), 0) < 0)
log_warn(LD_HIST, "Unable to write served descs statistics to disk!");
rep_hist_reset_desc_stats(now);
done:
tor_free(statsdir);
tor_free(filename);
tor_free(str);
return start_of_served_descs_stats_interval + WRITE_STATS_INTERVAL;
}
/* DOCDOC rep_hist_note_desc_served */
void
rep_hist_note_desc_served(const char * desc)
{
void *val;
uintptr_t count;
if (!served_descs)
return; // We're not collecting stats
val = digestmap_get(served_descs, desc);
count = (uintptr_t)val;
if (count != INT_MAX)
++count;
digestmap_set(served_descs, desc, (void*)count);
total_descriptor_downloads++;
}
/*** Connection statistics ***/
/** Start of the current connection stats interval or 0 if we're not
* collecting connection statistics. */
static time_t start_of_conn_stats_interval;
/** Initialize connection stats. */
void
rep_hist_conn_stats_init(time_t now)
{
start_of_conn_stats_interval = now;
}
/* Count connections that we read and wrote less than these many bytes
* from/to as below threshold. */
#define BIDI_THRESHOLD 20480
/* Count connections that we read or wrote at least this factor as many
* bytes from/to than we wrote or read to/from as mostly reading or
* writing. */
#define BIDI_FACTOR 10
/* Interval length in seconds for considering read and written bytes for
* connection stats. */
#define BIDI_INTERVAL 10
/** Start of next BIDI_INTERVAL second interval. */
static time_t bidi_next_interval = 0;
/** Number of connections that we read and wrote less than BIDI_THRESHOLD
* bytes from/to in BIDI_INTERVAL seconds. */
static uint32_t below_threshold = 0;
/** Number of connections that we read at least BIDI_FACTOR times more
* bytes from than we wrote to in BIDI_INTERVAL seconds. */
static uint32_t mostly_read = 0;
/** Number of connections that we wrote at least BIDI_FACTOR times more
* bytes to than we read from in BIDI_INTERVAL seconds. */
static uint32_t mostly_written = 0;
/** Number of connections that we read and wrote at least BIDI_THRESHOLD
* bytes from/to, but not BIDI_FACTOR times more in either direction in
* BIDI_INTERVAL seconds. */
static uint32_t both_read_and_written = 0;
/** Entry in a map from connection ID to the number of read and written
* bytes on this connection in a BIDI_INTERVAL second interval. */
typedef struct bidi_map_entry_t {
HT_ENTRY(bidi_map_entry_t) node;
uint64_t conn_id; /**< Connection ID */
size_t read; /**< Number of read bytes */
size_t written; /**< Number of written bytes */
} bidi_map_entry_t;
/** Map of OR connections together with the number of read and written
* bytes in the current BIDI_INTERVAL second interval. */
static HT_HEAD(bidimap, bidi_map_entry_t) bidi_map =
HT_INITIALIZER();
static int
bidi_map_ent_eq(const bidi_map_entry_t *a, const bidi_map_entry_t *b)
{
return a->conn_id == b->conn_id;
}
/* DOCDOC bidi_map_ent_hash */
static unsigned
bidi_map_ent_hash(const bidi_map_entry_t *entry)
{
return (unsigned) entry->conn_id;
}
HT_PROTOTYPE(bidimap, bidi_map_entry_t, node, bidi_map_ent_hash,
bidi_map_ent_eq);
HT_GENERATE(bidimap, bidi_map_entry_t, node, bidi_map_ent_hash,
bidi_map_ent_eq, 0.6, malloc, realloc, free);
/* DOCDOC bidi_map_free */
static void
bidi_map_free(void)
{
bidi_map_entry_t **ptr, **next, *ent;
for (ptr = HT_START(bidimap, &bidi_map); ptr; ptr = next) {
ent = *ptr;
next = HT_NEXT_RMV(bidimap, &bidi_map, ptr);
tor_free(ent);
}
HT_CLEAR(bidimap, &bidi_map);
}
/** Reset counters for conn statistics. */
void
rep_hist_reset_conn_stats(time_t now)
{
start_of_conn_stats_interval = now;
below_threshold = 0;
mostly_read = 0;
mostly_written = 0;
both_read_and_written = 0;
bidi_map_free();
}
/** Stop collecting connection stats in a way that we can re-start doing
* so in rep_hist_conn_stats_init(). */
void
rep_hist_conn_stats_term(void)
{
rep_hist_reset_conn_stats(0);
}
/** We read num_read bytes and wrote num_written from/to OR
* connection conn_id in second when. If this is the first
* observation in a new interval, sum up the last observations. Add bytes
* for this connection. */
void
rep_hist_note_or_conn_bytes(uint64_t conn_id, size_t num_read,
size_t num_written, time_t when)
{
if (!start_of_conn_stats_interval)
return;
/* Initialize */
if (bidi_next_interval == 0)
bidi_next_interval = when + BIDI_INTERVAL;
/* Sum up last period's statistics */
if (when >= bidi_next_interval) {
bidi_map_entry_t **ptr, **next, *ent;
for (ptr = HT_START(bidimap, &bidi_map); ptr; ptr = next) {
ent = *ptr;
if (ent->read + ent->written < BIDI_THRESHOLD)
below_threshold++;
else if (ent->read >= ent->written * BIDI_FACTOR)
mostly_read++;
else if (ent->written >= ent->read * BIDI_FACTOR)
mostly_written++;
else
both_read_and_written++;
next = HT_NEXT_RMV(bidimap, &bidi_map, ptr);
tor_free(ent);
}
while (when >= bidi_next_interval)
bidi_next_interval += BIDI_INTERVAL;
log_info(LD_GENERAL, "%d below threshold, %d mostly read, "
"%d mostly written, %d both read and written.",
below_threshold, mostly_read, mostly_written,
both_read_and_written);
}
/* Add this connection's bytes. */
if (num_read > 0 || num_written > 0) {
bidi_map_entry_t *entry, lookup;
lookup.conn_id = conn_id;
entry = HT_FIND(bidimap, &bidi_map, &lookup);
if (entry) {
entry->written += num_written;
entry->read += num_read;
} else {
entry = tor_malloc_zero(sizeof(bidi_map_entry_t));
entry->conn_id = conn_id;
entry->written = num_written;
entry->read = num_read;
HT_INSERT(bidimap, &bidi_map, entry);
}
}
}
/** Return a newly allocated string containing the connection statistics
* until now, or NULL if we're not collecting conn stats. Caller must
* ensure start_of_conn_stats_interval is in the past. */
char *
rep_hist_format_conn_stats(time_t now)
{
char *result, written[ISO_TIME_LEN+1];
if (!start_of_conn_stats_interval)
return NULL; /* Not initialized. */
tor_assert(now >= start_of_conn_stats_interval);
format_iso_time(written, now);
tor_asprintf(&result, "conn-bi-direct %s (%d s) %d,%d,%d,%d\n",
written,
(unsigned) (now - start_of_conn_stats_interval),
below_threshold,
mostly_read,
mostly_written,
both_read_and_written);
return result;
}
/** If 24 hours have passed since the beginning of the current conn stats
* period, write conn stats to $DATADIR/stats/conn-stats (possibly
* overwriting an existing file) and reset counters. Return when we would
* next want to write conn stats or 0 if we never want to write. */
time_t
rep_hist_conn_stats_write(time_t now)
{
char *statsdir = NULL, *filename = NULL, *str = NULL;
if (!start_of_conn_stats_interval)
return 0; /* Not initialized. */
if (start_of_conn_stats_interval + WRITE_STATS_INTERVAL > now)
goto done; /* Not ready to write */
/* Generate history string. */
str = rep_hist_format_conn_stats(now);
/* Reset counters. */
rep_hist_reset_conn_stats(now);
/* Try to write to disk. */
statsdir = get_datadir_fname("stats");
if (check_private_dir(statsdir, CPD_CREATE, get_options()->User) < 0) {
log_warn(LD_HIST, "Unable to create stats/ directory!");
goto done;
}
filename = get_datadir_fname2("stats", "conn-stats");
if (write_str_to_file(filename, str, 0) < 0)
log_warn(LD_HIST, "Unable to write conn stats to disk!");
done:
tor_free(str);
tor_free(filename);
tor_free(statsdir);
return start_of_conn_stats_interval + WRITE_STATS_INTERVAL;
}
/** Free all storage held by the OR/link history caches, by the
* bandwidth history arrays, by the port history, or by statistics . */
void
rep_hist_free_all(void)
{
digestmap_free(history_map, free_or_history);
tor_free(read_array);
tor_free(write_array);
tor_free(last_stability_doc);
tor_free(exit_bytes_read);
tor_free(exit_bytes_written);
tor_free(exit_streams);
built_last_stability_doc_at = 0;
predicted_ports_free();
bidi_map_free();
if (circuits_for_buffer_stats) {
SMARTLIST_FOREACH(circuits_for_buffer_stats, circ_buffer_stats_t *, s,
tor_free(s));
smartlist_free(circuits_for_buffer_stats);
circuits_for_buffer_stats = NULL;
}
rep_hist_desc_stats_term();
total_descriptor_downloads = 0;
}