[tor-commits] [tor/master] New torrc option to allow bucket refill intervals of less than 1 sec

commit 6b1d8321aef15a948ec32333a98217450bd02f78 Author: Florian Tschorsch tschorsch@informatik.uni-wuerzburg.de Date: Wed Sep 7 20:21:53 2011 -0400

New torrc option to allow bucket refill intervals of less than 1 sec

Implements bug3630. --- doc/tor.1.txt | 8 ++++ src/or/config.c | 8 ++++ src/or/connection.c | 64 +++++++++++++++++------------- src/or/main.c | 110 +++++++++++++++++++++++++++++++++++++++----------- src/or/or.h | 3 + 5 files changed, 141 insertions(+), 52 deletions(-)

diff --git a/doc/tor.1.txt b/doc/tor.1.txt index 4edee80..05f52f8 100644 --- a/doc/tor.1.txt +++ b/doc/tor.1.txt @@ -737,6 +737,14 @@ The following options are useful only for clients (that is, if unattached waiting for an appropriate circuit, before we fail it. (Default: 2 minutes.)

+**TokenBucketRefillInterval** __NUM__:: + Set the refill interval of Tor's token bucket to NUM milliseconds. + NUM must be positive and either a divisor or a multiple of 1 second. + Note that this option retains the configured bandwidth limits and refills + token buckets only in ratio to the interval. This option will be ignored + when Tor was built with Libevent's bufferevents enabled. (Default: 1 second) + + **TrackHostExits** __host__,__.domain__,__...__:: For each value in the comma separated list, Tor will track recent connections to hosts that match this value and attempt to reuse the same diff --git a/src/or/config.c b/src/or/config.c index bc77b3a..b04cee4 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -386,6 +386,7 @@ static config_var_t _option_vars[] = { OBSOLETE("SysLog"), V(TestSocks, BOOL, "0"), OBSOLETE("TestVia"), + V(TokenBucketRefillInterval, MSEC_INTERVAL, "10 msec"), V(TrackHostExits, CSV, NULL), V(TrackHostExitsExpire, INTERVAL, "30 minutes"), OBSOLETE("TrafficShaping"), @@ -1382,6 +1383,13 @@ options_act(const or_options_t *old_options) if (accounting_is_enabled(options)) configure_accounting(time(NULL));

+ if (options->TokenBucketRefillInterval < 0 + || options->TokenBucketRefillInterval > 1000) { + log_warn(LD_CONFIG, "Token bucket refill interval must be in the range " + "of [0:1000]"); + return -1; + } + #ifdef USE_BUFFEREVENTS /* If we're using the bufferevents implementation and our rate limits * changed, we need to tell the rate-limiting system about it. */ diff --git a/src/or/connection.c b/src/or/connection.c index 0092030..42d7e2f 100644 --- a/src/or/connection.c +++ b/src/or/connection.c @@ -2389,20 +2389,21 @@ connection_bucket_init(void) }

/** Refill a single <b>bucket</b> called <b>name</b> with bandwidth rate - * <b>rate</b> and bandwidth burst <b>burst</b>, assuming that - * <b>seconds_elapsed</b> seconds have passed since the last call. - **/ + * per millisecond <b>rate</b> and bandwidth burst per refill interval + * <b>burst</b>, assuming that <b>milliseconds_elapsed</b> milliseconds + * have passed since the last call. */ static void connection_bucket_refill_helper(int *bucket, int rate, int burst, - int seconds_elapsed, const char *name) + int milliseconds_elapsed, + const char *name) { int starting_bucket = *bucket; - if (starting_bucket < burst && seconds_elapsed) { - if (((burst - starting_bucket)/seconds_elapsed) < rate) { + if (starting_bucket < burst && milliseconds_elapsed) { + if (((burst - starting_bucket)/milliseconds_elapsed) < rate) { *bucket = burst; /* We would overflow the bucket; just set it to * the maximum. */ } else { - int incr = rate*seconds_elapsed; + int incr = rate*milliseconds_elapsed; *bucket += incr; if (*bucket > burst || *bucket < starting_bucket) { /* If we overflow the burst, or underflow our starting bucket, @@ -2416,41 +2417,46 @@ connection_bucket_refill_helper(int *bucket, int rate, int burst, } }

-/** A second has rolled over; increment buckets appropriately. */ +/** Time has passed; increment buckets appropriately. */ void -connection_bucket_refill(int seconds_elapsed, time_t now) +connection_bucket_refill(int milliseconds_elapsed, time_t now) { const or_options_t *options = get_options(); smartlist_t *conns = get_connection_array(); - int relayrate, relayburst; + int bandwidthrate, bandwidthburst, relayrate, relayburst; + + bandwidthrate = (int)options->BandwidthRate / 1000; + bandwidthburst = (int)options->BandwidthBurst;

if (options->RelayBandwidthRate) { - relayrate = (int)options->RelayBandwidthRate; + relayrate = (int)options->RelayBandwidthRate / 1000; relayburst = (int)options->RelayBandwidthBurst; } else { - relayrate = (int)options->BandwidthRate; - relayburst = (int)options->BandwidthBurst; + relayrate = bandwidthrate; + relayburst = bandwidthburst; }

- tor_assert(seconds_elapsed >= 0); + tor_assert(milliseconds_elapsed >= 0);

write_buckets_empty_last_second = global_relayed_write_bucket <= 0 || global_write_bucket <= 0;

/* refill the global buckets */ connection_bucket_refill_helper(&global_read_bucket, - (int)options->BandwidthRate, - (int)options->BandwidthBurst, - seconds_elapsed, "global_read_bucket"); + bandwidthrate, bandwidthburst, + milliseconds_elapsed, + "global_read_bucket"); connection_bucket_refill_helper(&global_write_bucket, - (int)options->BandwidthRate, - (int)options->BandwidthBurst, - seconds_elapsed, "global_write_bucket"); + bandwidthrate, bandwidthburst, + milliseconds_elapsed, + "global_read_bucket"); connection_bucket_refill_helper(&global_relayed_read_bucket, - relayrate, relayburst, seconds_elapsed, + relayrate, relayburst, + milliseconds_elapsed, "global_relayed_read_bucket"); connection_bucket_refill_helper(&global_relayed_write_bucket, - relayrate, relayburst, seconds_elapsed, + relayrate, relayburst, + milliseconds_elapsed, "global_relayed_write_bucket");

/* refill the per-connection buckets */ @@ -2458,18 +2464,20 @@ connection_bucket_refill(int seconds_elapsed, time_t now) { if (connection_speaks_cells(conn)) { or_connection_t *or_conn = TO_OR_CONN(conn); + int orbandwidthrate = or_conn->bandwidthrate / 1000; + int orbandwidthburst = or_conn->bandwidthburst; if (connection_bucket_should_increase(or_conn->read_bucket, or_conn)) { connection_bucket_refill_helper(&or_conn->read_bucket, - or_conn->bandwidthrate, - or_conn->bandwidthburst, - seconds_elapsed, + orbandwidthrate, + orbandwidthburst, + milliseconds_elapsed, "or_conn->read_bucket"); } if (connection_bucket_should_increase(or_conn->write_bucket, or_conn)) { connection_bucket_refill_helper(&or_conn->write_bucket, - or_conn->bandwidthrate, - or_conn->bandwidthburst, - seconds_elapsed, + orbandwidthrate, + orbandwidthburst, + milliseconds_elapsed, "or_conn->write_bucket"); } } diff --git a/src/or/main.c b/src/or/main.c index ad5558e..1a95e31 100644 --- a/src/or/main.c +++ b/src/or/main.c @@ -91,10 +91,10 @@ static int stats_prev_global_read_bucket; /** What was the write bucket before the last second_elapsed_callback() call? * (used to determine how many bytes we've written). */ static int stats_prev_global_write_bucket; -#else +#endif + static uint64_t stats_prev_n_read = 0; static uint64_t stats_prev_n_written = 0; -#endif

/* XXX we might want to keep stats about global_relayed_*_bucket too. Or not.*/ /** How many bytes have we read since we started the process? */ @@ -1507,9 +1507,6 @@ second_elapsed_callback(periodic_timer_t *timer, void *arg) size_t bytes_written; size_t bytes_read; int seconds_elapsed; -#ifdef USE_BUFFEREVENTS - uint64_t cur_read,cur_written; -#endif const or_options_t *options = get_options(); (void)timer; (void)arg; @@ -1523,30 +1520,28 @@ second_elapsed_callback(periodic_timer_t *timer, void *arg) /* the second has rolled over. check more stuff. */ seconds_elapsed = current_second ? (int)(now - current_second) : 0; #ifdef USE_BUFFEREVENTS - connection_get_rate_limit_totals(&cur_read, &cur_written); - bytes_written = (size_t)(cur_written - stats_prev_n_written); - bytes_read = (size_t)(cur_read - stats_prev_n_read); + { + uint64_t cur_read,cur_written; + connection_get_rate_limit_totals(&cur_read, &cur_written); + bytes_written = (size_t)(cur_written - stats_prev_n_written); + bytes_read = (size_t)(cur_read - stats_prev_n_read); + stats_n_bytes_read += bytes_read; + stats_n_bytes_written += bytes_written; + if (accounting_is_enabled(options) && seconds_elapsed >= 0) + accounting_add_bytes(bytes_read, bytes_written, seconds_elapsed); + stats_prev_n_written = cur_written; + stats_prev_n_read = cur_read; + } #else - bytes_written = stats_prev_global_write_bucket - global_write_bucket; - bytes_read = stats_prev_global_read_bucket - global_read_bucket; + bytes_read = (size_t)(stats_n_bytes_read - stats_prev_n_read); + bytes_written = (size_t)(stats_n_bytes_written - stats_prev_n_written); + stats_prev_n_read = stats_n_bytes_read; + stats_prev_n_written = stats_n_bytes_written; #endif - stats_n_bytes_read += bytes_read; - stats_n_bytes_written += bytes_written; - if (accounting_is_enabled(options) && seconds_elapsed >= 0) - accounting_add_bytes(bytes_read, bytes_written, seconds_elapsed); + control_event_bandwidth_used((uint32_t)bytes_read,(uint32_t)bytes_written); control_event_stream_bandwidth_used();

- if (seconds_elapsed > 0) - connection_bucket_refill(seconds_elapsed, now); -#ifdef USE_BUFFEREVENTS - stats_prev_n_written = cur_written; - stats_prev_n_read = cur_read; -#else - stats_prev_global_read_bucket = global_read_bucket; - stats_prev_global_write_bucket = global_write_bucket; -#endif - if (server_mode(options) && !we_are_hibernating() && seconds_elapsed > 0 && @@ -1594,6 +1589,57 @@ second_elapsed_callback(periodic_timer_t *timer, void *arg) current_second = now; /* remember which second it is, for next time */ }

+#ifndef USE_BUFFEREVENTS +/** Timer: used to invoke refill_callback(). */ +static periodic_timer_t *refill_timer = NULL; + +/** Libevent callback: invoked periodically to refill token buckets + * and count r/w bytes. It is only used when bufferevents are disabled. */ +static void +refill_callback(periodic_timer_t *timer, void *arg) +{ + static struct timeval current_millisecond; + struct timeval now; + + size_t bytes_written; + size_t bytes_read; + int milliseconds_elapsed = 0; + int seconds_rolled_over = 0; + + const or_options_t *options = get_options(); + + (void)timer; + (void)arg; + + tor_gettimeofday(&now); + + /* If this is our first time, no time has passed. */ + if (current_millisecond.tv_sec) { + long mdiff = tv_mdiff(&current_millisecond, &now); + if (mdiff > INT_MAX) + mdiff = INT_MAX; + milliseconds_elapsed = (int)mdiff; + seconds_rolled_over = (int)(now.tv_sec - current_millisecond.tv_sec); + } + + bytes_written = stats_prev_global_write_bucket - global_write_bucket; + bytes_read = stats_prev_global_read_bucket - global_read_bucket; + + stats_n_bytes_read += bytes_read; + stats_n_bytes_written += bytes_written; + if (accounting_is_enabled(options) && milliseconds_elapsed >= 0) + accounting_add_bytes(bytes_read, bytes_written, seconds_rolled_over); + + if (milliseconds_elapsed > 0) + connection_bucket_refill(milliseconds_elapsed, now.tv_sec); + + stats_prev_global_read_bucket = global_read_bucket; + stats_prev_global_write_bucket = global_write_bucket; + + current_millisecond = now; /* remember what time it is, for next time */ +} +#endif + #ifndef MS_WINDOWS /** Called when a possibly ignorable libevent error occurs; ensures that we * don't get into an infinite loop by ignoring too many errors from @@ -1791,6 +1837,22 @@ do_main_loop(void) tor_assert(second_timer); }

+#ifndef USE_BUFFEREVENTS + if (!refill_timer) { + struct timeval refill_interval; + int msecs = get_options()->TokenBucketRefillInterval; + + refill_interval.tv_sec = msecs/1000; + refill_interval.tv_usec = (msecs%1000)*1000; + + refill_timer = periodic_timer_new(tor_libevent_get_base(), + &refill_interval, + refill_callback, + NULL); + tor_assert(refill_timer); + } +#endif + for (;;) { if (nt_service_is_stopping()) return 0; diff --git a/src/or/or.h b/src/or/or.h index 56f34fc..37eea1c 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -3107,6 +3107,9 @@ typedef struct { * log whether it was DNS-leaking or not? */ int HardwareAccel; /**< Boolean: Should we enable OpenSSL hardware * acceleration where available? */ + /** Token Bucket Refill resolution in milliseconds (ignored when + * bufferevents are enabled) */ + int TokenBucketRefillInterval; char *AccelName; /**< Optional hardware acceleration engine name. */ char *AccelDir; /**< Optional hardware acceleration engine search dir. */ int UseEntryGuards; /**< Boolean: Do we try to enter from a smallish number