1 /* Copyright (c) 2001 Matej Pfajfar.
2 * Copyright (c) 2001-2004, Roger Dingledine.
3 * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
4 * Copyright (c) 2007-2011, The Tor Project, Inc. */
5 /* See LICENSE for licensing information */
9 * \brief Launch the right sort of circuits and attach streams to them.
13 #include "circuitbuild.h"
14 #include "circuitlist.h"
15 #include "circuituse.h"
17 #include "connection.h"
18 #include "connection_edge.h"
21 #include "rendclient.h"
22 #include "rendcommon.h"
23 #include "rendservice.h"
26 #include "routerlist.h"
28 /********* START VARIABLES **********/
30 extern circuit_t
*global_circuitlist
; /* from circuitlist.c */
32 /********* END VARIABLES ************/
34 static void circuit_expire_old_circuits_clientside(void);
35 static void circuit_increment_failure_count(void);
37 /** Return 1 if <b>circ</b> could be returned by circuit_get_best().
41 circuit_is_acceptable(circuit_t
*circ
, edge_connection_t
*conn
,
42 int must_be_open
, uint8_t purpose
,
43 int need_uptime
, int need_internal
,
46 routerinfo_t
*exitrouter
;
47 cpath_build_state_t
*build_state
;
50 tor_assert(conn
->socks_request
);
52 if (!CIRCUIT_IS_ORIGIN(circ
))
53 return 0; /* this circ doesn't start at us */
54 if (must_be_open
&& (circ
->state
!= CIRCUIT_STATE_OPEN
|| !circ
->n_conn
))
55 return 0; /* ignore non-open circs */
56 if (circ
->marked_for_close
)
59 /* if this circ isn't our purpose, skip. */
60 if (purpose
== CIRCUIT_PURPOSE_C_REND_JOINED
&& !must_be_open
) {
61 if (circ
->purpose
!= CIRCUIT_PURPOSE_C_ESTABLISH_REND
&&
62 circ
->purpose
!= CIRCUIT_PURPOSE_C_REND_READY
&&
63 circ
->purpose
!= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
&&
64 circ
->purpose
!= CIRCUIT_PURPOSE_C_REND_JOINED
)
66 } else if (purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
&&
68 if (circ
->purpose
!= CIRCUIT_PURPOSE_C_INTRODUCING
&&
69 circ
->purpose
!= CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
)
72 if (purpose
!= circ
->purpose
)
76 if (purpose
== CIRCUIT_PURPOSE_C_GENERAL
)
77 if (circ
->timestamp_dirty
&&
78 circ
->timestamp_dirty
+get_options()->MaxCircuitDirtiness
<= now
)
81 /* decide if this circ is suitable for this conn */
83 /* for rend circs, circ->cpath->prev is not the last router in the
84 * circuit, it's the magical extra bob hop. so just check the nickname
85 * of the one we meant to finish at.
87 build_state
= TO_ORIGIN_CIRCUIT(circ
)->build_state
;
88 exitrouter
= build_state_get_exit_router(build_state
);
90 if (need_uptime
&& !build_state
->need_uptime
)
92 if (need_internal
!= build_state
->is_internal
)
95 if (purpose
== CIRCUIT_PURPOSE_C_GENERAL
) {
96 if (!exitrouter
&& !build_state
->onehop_tunnel
) {
97 log_debug(LD_CIRC
,"Not considering circuit with unknown router.");
98 return 0; /* this circuit is screwed and doesn't know it yet,
99 * or is a rendezvous circuit. */
101 if (build_state
->onehop_tunnel
) {
102 if (!conn
->want_onehop
) {
103 log_debug(LD_CIRC
,"Skipping one-hop circuit.");
106 tor_assert(conn
->chosen_exit_name
);
107 if (build_state
->chosen_exit
) {
108 char digest
[DIGEST_LEN
];
109 if (hexdigest_to_digest(conn
->chosen_exit_name
, digest
) < 0)
110 return 0; /* broken digest, we don't want it */
111 if (memcmp(digest
, build_state
->chosen_exit
->identity_digest
,
113 return 0; /* this is a circuit to somewhere else */
114 if (tor_digest_is_zero(digest
)) {
115 /* we don't know the digest; have to compare addr:port */
117 int r
= tor_addr_from_str(&addr
, conn
->socks_request
->address
);
119 !tor_addr_eq(&build_state
->chosen_exit
->addr
, &addr
) ||
120 build_state
->chosen_exit
->port
!= conn
->socks_request
->port
)
125 if (conn
->want_onehop
) {
126 /* don't use three-hop circuits -- that could hurt our anonymity. */
130 if (exitrouter
&& !connection_ap_can_use_exit(conn
, exitrouter
)) {
131 /* can't exit from this router */
134 } else { /* not general */
135 origin_circuit_t
*ocirc
= TO_ORIGIN_CIRCUIT(circ
);
136 if ((conn
->rend_data
&& !ocirc
->rend_data
) ||
137 (!conn
->rend_data
&& ocirc
->rend_data
) ||
138 (conn
->rend_data
&& ocirc
->rend_data
&&
139 rend_cmp_service_ids(conn
->rend_data
->onion_address
,
140 ocirc
->rend_data
->onion_address
))) {
141 /* this circ is not for this conn */
148 /** Return 1 if circuit <b>a</b> is better than circuit <b>b</b> for
149 * <b>purpose</b>, and return 0 otherwise. Used by circuit_get_best.
152 circuit_is_better(circuit_t
*a
, circuit_t
*b
, uint8_t purpose
)
155 case CIRCUIT_PURPOSE_C_GENERAL
:
156 /* if it's used but less dirty it's best;
157 * else if it's more recently created it's best
159 if (b
->timestamp_dirty
) {
160 if (a
->timestamp_dirty
&&
161 a
->timestamp_dirty
> b
->timestamp_dirty
)
164 if (a
->timestamp_dirty
||
165 timercmp(&a
->timestamp_created
, &b
->timestamp_created
, >))
167 if (CIRCUIT_IS_ORIGIN(b
) &&
168 TO_ORIGIN_CIRCUIT(b
)->build_state
->is_internal
)
169 /* XXX023 what the heck is this internal thing doing here. I
170 * think we can get rid of it. circuit_is_acceptable() already
171 * makes sure that is_internal is exactly what we need it to
176 case CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
:
177 /* the closer it is to ack_wait the better it is */
178 if (a
->purpose
> b
->purpose
)
181 case CIRCUIT_PURPOSE_C_REND_JOINED
:
182 /* the closer it is to rend_joined the better it is */
183 if (a
->purpose
> b
->purpose
)
190 /** Find the best circ that conn can use, preferably one which is
191 * dirty. Circ must not be too old.
193 * Conn must be defined.
195 * If must_be_open, ignore circs not in CIRCUIT_STATE_OPEN.
197 * circ_purpose specifies what sort of circuit we must have.
198 * It can be C_GENERAL, C_INTRODUCE_ACK_WAIT, or C_REND_JOINED.
200 * If it's REND_JOINED and must_be_open==0, then return the closest
201 * rendezvous-purposed circuit that you can find.
203 * If it's INTRODUCE_ACK_WAIT and must_be_open==0, then return the
204 * closest introduce-purposed circuit that you can find.
206 static origin_circuit_t
*
207 circuit_get_best(edge_connection_t
*conn
, int must_be_open
, uint8_t purpose
,
208 int need_uptime
, int need_internal
)
210 circuit_t
*circ
, *best
=NULL
;
212 int intro_going_on_but_too_old
= 0;
216 tor_assert(purpose
== CIRCUIT_PURPOSE_C_GENERAL
||
217 purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
||
218 purpose
== CIRCUIT_PURPOSE_C_REND_JOINED
);
220 tor_gettimeofday(&now
);
222 for (circ
=global_circuitlist
;circ
;circ
= circ
->next
) {
223 if (!circuit_is_acceptable(circ
,conn
,must_be_open
,purpose
,
224 need_uptime
,need_internal
,now
.tv_sec
))
227 if (purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
&&
228 !must_be_open
&& circ
->state
!= CIRCUIT_STATE_OPEN
&&
229 tv_mdiff(&now
, &circ
->timestamp_created
) > circ_times
.timeout_ms
) {
230 intro_going_on_but_too_old
= 1;
234 /* now this is an acceptable circ to hand back. but that doesn't
235 * mean it's the *best* circ to hand back. try to decide.
237 if (!best
|| circuit_is_better(circ
,best
,purpose
))
241 if (!best
&& intro_going_on_but_too_old
)
242 log_info(LD_REND
|LD_CIRC
, "There is an intro circuit being created "
243 "right now, but it has already taken quite a while. Starting "
246 return best
? TO_ORIGIN_CIRCUIT(best
) : NULL
;
250 /** Check whether, according to the policies in <b>options</b>, the
251 * circuit <b>circ</b> makes sense. */
252 /* XXXX currently only checks Exclude{Exit}Nodes; it should check more.
253 * Also, it doesn't have the right definition of an exit circuit. Also,
254 * it's never called. */
256 circuit_conforms_to_options(const origin_circuit_t
*circ
,
257 const or_options_t
*options
)
259 const crypt_path_t
*cpath
, *cpath_next
= NULL
;
261 /* first check if it includes any excluded nodes */
262 for (cpath
= circ
->cpath
; cpath_next
!= circ
->cpath
; cpath
= cpath_next
) {
263 cpath_next
= cpath
->next
;
264 if (routerset_contains_extendinfo(options
->ExcludeNodes
,
269 /* then consider the final hop */
270 if (routerset_contains_extendinfo(options
->ExcludeExitNodes
,
271 circ
->cpath
->prev
->extend_info
))
278 /** Close all circuits that start at us, aren't open, and were born
279 * at least CircuitBuildTimeout seconds ago.
282 circuit_expire_building(void)
284 circuit_t
*victim
, *next_circ
= global_circuitlist
;
285 /* circ_times.timeout_ms and circ_times.close_ms are from
286 * circuit_build_times_get_initial_timeout() if we haven't computed
287 * custom timeouts yet */
288 struct timeval general_cutoff
, begindir_cutoff
, fourhop_cutoff
,
289 cannibalize_cutoff
, close_cutoff
, extremely_old_cutoff
;
291 struct timeval introcirc_cutoff
;
292 cpath_build_state_t
*build_state
;
294 tor_gettimeofday(&now
);
295 #define SET_CUTOFF(target, msec) do { \
296 long ms = tor_lround(msec); \
297 struct timeval diff; \
298 diff.tv_sec = ms / 1000; \
299 diff.tv_usec = (int)((ms % 1000) * 1000); \
300 timersub(&now, &diff, &target); \
303 SET_CUTOFF(general_cutoff
, circ_times
.timeout_ms
);
304 SET_CUTOFF(begindir_cutoff
, circ_times
.timeout_ms
/ 2.0);
305 SET_CUTOFF(fourhop_cutoff
, circ_times
.timeout_ms
* (4/3.0));
306 SET_CUTOFF(cannibalize_cutoff
, circ_times
.timeout_ms
/ 2.0);
307 SET_CUTOFF(close_cutoff
, circ_times
.close_ms
);
308 SET_CUTOFF(extremely_old_cutoff
, circ_times
.close_ms
*2 + 1000);
310 introcirc_cutoff
= begindir_cutoff
;
313 struct timeval cutoff
;
315 next_circ
= next_circ
->next
;
316 if (!CIRCUIT_IS_ORIGIN(victim
) || /* didn't originate here */
317 victim
->marked_for_close
) /* don't mess with marked circs */
320 build_state
= TO_ORIGIN_CIRCUIT(victim
)->build_state
;
321 if (build_state
&& build_state
->onehop_tunnel
)
322 cutoff
= begindir_cutoff
;
323 else if (build_state
&& build_state
->desired_path_len
== 4
324 && !TO_ORIGIN_CIRCUIT(victim
)->has_opened
)
325 cutoff
= fourhop_cutoff
;
326 else if (TO_ORIGIN_CIRCUIT(victim
)->has_opened
)
327 cutoff
= cannibalize_cutoff
;
328 else if (victim
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
)
329 cutoff
= introcirc_cutoff
;
330 else if (victim
->purpose
== CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
)
331 cutoff
= close_cutoff
;
333 cutoff
= general_cutoff
;
335 if (timercmp(&victim
->timestamp_created
, &cutoff
, >))
336 continue; /* it's still young, leave it alone */
339 /* some debug logs, to help track bugs */
340 if (victim
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
&&
341 victim
->timestamp_created
<= introcirc_cutoff
&&
342 victim
->timestamp_created
> general_cutoff
)
343 log_info(LD_REND
|LD_CIRC
, "Timing out introduction circuit which we "
344 "would not have done if it had been a general circuit.");
346 if (victim
->purpose
>= CIRCUIT_PURPOSE_C_INTRODUCING
&&
347 victim
->purpose
<= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
) {
348 if (!victim
->timestamp_dirty
)
349 log_fn(LOG_DEBUG
,"Considering %sopen purpose %d to %s (circid %d)."
351 victim
->state
== CIRCUIT_STATE_OPEN
? "" : "non",
352 victim
->purpose
, victim
->build_state
->chosen_exit_name
,
355 log_fn(LOG_DEBUG
,"Considering %sopen purpose %d to %s (circid %d). "
356 "%d secs since dirty.",
357 victim
->state
== CIRCUIT_STATE_OPEN
? "" : "non",
358 victim
->purpose
, victim
->build_state
->chosen_exit_name
,
360 (int)(now
- victim
->timestamp_dirty
));
364 /* if circ is !open, or if it's open but purpose is a non-finished
365 * intro or rend, then mark it for close */
366 if (victim
->state
== CIRCUIT_STATE_OPEN
) {
367 switch (victim
->purpose
) {
368 default: /* most open circuits can be left alone. */
369 continue; /* yes, continue inside a switch refers to the nearest
370 * enclosing loop. C is smart. */
371 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
372 case CIRCUIT_PURPOSE_C_INTRODUCING
:
373 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
374 break; /* too old, need to die */
375 case CIRCUIT_PURPOSE_C_REND_READY
:
376 /* it's a rend_ready circ -- has it already picked a query? */
377 /* c_rend_ready circs measure age since timestamp_dirty,
378 * because that's set when they switch purposes
380 if (TO_ORIGIN_CIRCUIT(victim
)->rend_data
||
381 victim
->timestamp_dirty
> cutoff
.tv_sec
)
384 case CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
:
385 case CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
:
386 /* rend and intro circs become dirty each time they
387 * make an introduction attempt. so timestamp_dirty
388 * will reflect the time since the last attempt.
390 if (victim
->timestamp_dirty
> cutoff
.tv_sec
)
394 } else { /* circuit not open, consider recording failure as timeout */
395 int first_hop_succeeded
= TO_ORIGIN_CIRCUIT(victim
)->cpath
&&
396 TO_ORIGIN_CIRCUIT(victim
)->cpath
->state
== CPATH_STATE_OPEN
;
398 if (TO_ORIGIN_CIRCUIT(victim
)->p_streams
!= NULL
) {
399 log_warn(LD_BUG
, "Circuit %d (purpose %d, %s) has timed out, "
400 "yet has attached streams!",
401 TO_ORIGIN_CIRCUIT(victim
)->global_identifier
,
403 circuit_purpose_to_string(victim
->purpose
));
404 tor_fragile_assert();
408 if (circuit_timeout_want_to_count_circ(TO_ORIGIN_CIRCUIT(victim
)) &&
409 circuit_build_times_enough_to_compute(&circ_times
)) {
410 /* Circuits are allowed to last longer for measurement.
411 * Switch their purpose and wait. */
412 if (victim
->purpose
!= CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
) {
413 control_event_circuit_status(TO_ORIGIN_CIRCUIT(victim
),
415 END_CIRC_REASON_TIMEOUT
);
416 victim
->purpose
= CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
;
417 /* Record this failure to check for too many timeouts
418 * in a row. This function does not record a time value yet
419 * (we do that later); it only counts the fact that we did
421 circuit_build_times_count_timeout(&circ_times
,
422 first_hop_succeeded
);
427 * If the circuit build time is much greater than we would have cut
428 * it off at, we probably had a suspend event along this codepath,
429 * and we should discard the value.
431 if (timercmp(&victim
->timestamp_created
, &extremely_old_cutoff
, <)) {
433 "Extremely large value for circuit build timeout: %lds. "
434 "Assuming clock jump. Purpose %d (%s)",
435 (long)(now
.tv_sec
- victim
->timestamp_created
.tv_sec
),
437 circuit_purpose_to_string(victim
->purpose
));
438 } else if (circuit_build_times_count_close(&circ_times
,
440 victim
->timestamp_created
.tv_sec
)) {
441 circuit_build_times_set_timeout(&circ_times
);
447 log_info(LD_CIRC
,"Abandoning circ %s:%d:%d (state %d:%s, purpose %d)",
448 victim
->n_conn
->_base
.address
, victim
->n_conn
->_base
.port
,
450 victim
->state
, circuit_state_to_string(victim
->state
),
453 log_info(LD_CIRC
,"Abandoning circ %d (state %d:%s, purpose %d)",
454 victim
->n_circ_id
, victim
->state
,
455 circuit_state_to_string(victim
->state
), victim
->purpose
);
457 circuit_log_path(LOG_INFO
,LD_CIRC
,TO_ORIGIN_CIRCUIT(victim
));
458 if (victim
->purpose
== CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
)
459 circuit_mark_for_close(victim
, END_CIRC_REASON_MEASUREMENT_EXPIRED
);
461 circuit_mark_for_close(victim
, END_CIRC_REASON_TIMEOUT
);
465 /** Remove any elements in <b>needed_ports</b> that are handled by an
466 * open or in-progress circuit.
469 circuit_remove_handled_ports(smartlist_t
*needed_ports
)
474 for (i
= 0; i
< smartlist_len(needed_ports
); ++i
) {
475 port
= smartlist_get(needed_ports
, i
);
477 if (circuit_stream_is_being_handled(NULL
, *port
,
478 MIN_CIRCUITS_HANDLING_STREAM
)) {
479 // log_debug(LD_CIRC,"Port %d is already being handled; removing.", port);
480 smartlist_del(needed_ports
, i
--);
483 log_debug(LD_CIRC
,"Port %d is not handled.", *port
);
488 /** Return 1 if at least <b>min</b> general-purpose non-internal circuits
489 * will have an acceptable exit node for exit stream <b>conn</b> if it
490 * is defined, else for "*:port".
494 circuit_stream_is_being_handled(edge_connection_t
*conn
,
495 uint16_t port
, int min
)
498 routerinfo_t
*exitrouter
;
500 time_t now
= time(NULL
);
501 int need_uptime
= smartlist_string_num_isin(get_options()->LongLivedPorts
,
502 conn
? conn
->socks_request
->port
: port
);
504 for (circ
=global_circuitlist
;circ
;circ
= circ
->next
) {
505 if (CIRCUIT_IS_ORIGIN(circ
) &&
506 !circ
->marked_for_close
&&
507 circ
->purpose
== CIRCUIT_PURPOSE_C_GENERAL
&&
508 (!circ
->timestamp_dirty
||
509 circ
->timestamp_dirty
+ get_options()->MaxCircuitDirtiness
> now
)) {
510 cpath_build_state_t
*build_state
= TO_ORIGIN_CIRCUIT(circ
)->build_state
;
511 if (build_state
->is_internal
|| build_state
->onehop_tunnel
)
514 exitrouter
= build_state_get_exit_router(build_state
);
515 if (exitrouter
&& (!need_uptime
|| build_state
->need_uptime
)) {
518 ok
= connection_ap_can_use_exit(conn
, exitrouter
);
520 addr_policy_result_t r
= compare_addr_to_addr_policy(
521 0, port
, exitrouter
->exit_policy
);
522 ok
= r
!= ADDR_POLICY_REJECTED
&& r
!= ADDR_POLICY_PROBABLY_REJECTED
;
534 /** Don't keep more than this many unused open circuits around. */
535 #define MAX_UNUSED_OPEN_CIRCUITS 14
537 /** Figure out how many circuits we have open that are clean. Make
538 * sure it's enough for all the upcoming behaviors we predict we'll have.
539 * But put an upper bound on the total number of circuits.
542 circuit_predict_and_launch_new(void)
545 int num
=0, num_internal
=0, num_uptime_internal
=0;
546 int hidserv_needs_uptime
=0, hidserv_needs_capacity
=1;
547 int port_needs_uptime
=0, port_needs_capacity
=1;
548 time_t now
= time(NULL
);
551 /* First, count how many of each type of circuit we have already. */
552 for (circ
=global_circuitlist
;circ
;circ
= circ
->next
) {
553 cpath_build_state_t
*build_state
;
554 if (!CIRCUIT_IS_ORIGIN(circ
))
556 if (circ
->marked_for_close
)
557 continue; /* don't mess with marked circs */
558 if (circ
->timestamp_dirty
)
559 continue; /* only count clean circs */
560 if (circ
->purpose
!= CIRCUIT_PURPOSE_C_GENERAL
)
561 continue; /* only pay attention to general-purpose circs */
562 build_state
= TO_ORIGIN_CIRCUIT(circ
)->build_state
;
563 if (build_state
->onehop_tunnel
)
566 if (build_state
->is_internal
)
568 if (build_state
->need_uptime
&& build_state
->is_internal
)
569 num_uptime_internal
++;
572 /* If that's enough, then stop now. */
573 if (num
>= MAX_UNUSED_OPEN_CIRCUITS
)
574 return; /* we already have many, making more probably will hurt */
576 /* Second, see if we need any more exit circuits. */
577 /* check if we know of a port that's been requested recently
578 * and no circuit is currently available that can handle it. */
579 if (!circuit_all_predicted_ports_handled(now
, &port_needs_uptime
,
580 &port_needs_capacity
)) {
581 if (port_needs_uptime
)
582 flags
|= CIRCLAUNCH_NEED_UPTIME
;
583 if (port_needs_capacity
)
584 flags
|= CIRCLAUNCH_NEED_CAPACITY
;
586 "Have %d clean circs (%d internal), need another exit circ.",
588 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
592 /* Third, see if we need any more hidden service (server) circuits. */
593 if (num_rend_services() && num_uptime_internal
< 3) {
594 flags
= (CIRCLAUNCH_NEED_CAPACITY
| CIRCLAUNCH_NEED_UPTIME
|
595 CIRCLAUNCH_IS_INTERNAL
);
597 "Have %d clean circs (%d internal), need another internal "
598 "circ for my hidden service.",
600 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
604 /* Fourth, see if we need any more hidden service (client) circuits. */
605 if (rep_hist_get_predicted_internal(now
, &hidserv_needs_uptime
,
606 &hidserv_needs_capacity
) &&
607 ((num_uptime_internal
<2 && hidserv_needs_uptime
) ||
609 if (hidserv_needs_uptime
)
610 flags
|= CIRCLAUNCH_NEED_UPTIME
;
611 if (hidserv_needs_capacity
)
612 flags
|= CIRCLAUNCH_NEED_CAPACITY
;
613 flags
|= CIRCLAUNCH_IS_INTERNAL
;
615 "Have %d clean circs (%d uptime-internal, %d internal), need"
616 " another hidden service circ.",
617 num
, num_uptime_internal
, num_internal
);
618 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
622 /* Finally, check to see if we still need more circuits to learn
623 * a good build timeout. But if we're close to our max number we
624 * want, don't do another -- we want to leave a few slots open so
625 * we can still build circuits preemptively as needed. */
626 if (num
< MAX_UNUSED_OPEN_CIRCUITS
-2 &&
627 circuit_build_times_needs_circuits_now(&circ_times
)) {
628 flags
= CIRCLAUNCH_NEED_CAPACITY
;
630 "Have %d clean circs need another buildtime test circ.", num
);
631 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
636 /** Build a new test circuit every 5 minutes */
637 #define TESTING_CIRCUIT_INTERVAL 300
639 /** This function is called once a second, if router_have_min_dir_info() is
640 * true. Its job is to make sure all services we offer have enough circuits
641 * available. Some services just want enough circuits for current tasks,
642 * whereas others want a minimum set of idle circuits hanging around.
645 circuit_build_needed_circs(time_t now
)
647 static time_t time_to_new_circuit
= 0;
648 or_options_t
*options
= get_options();
650 /* launch a new circ for any pending streams that need one */
651 connection_ap_attach_pending();
653 /* make sure any hidden services have enough intro points */
654 rend_services_introduce();
656 if (time_to_new_circuit
< now
) {
657 circuit_reset_failure_count(1);
658 time_to_new_circuit
= now
+ options
->NewCircuitPeriod
;
659 if (proxy_mode(get_options()))
660 addressmap_clean(now
);
661 circuit_expire_old_circuits_clientside();
663 #if 0 /* disable for now, until predict-and-launch-new can cull leftovers */
664 circ
= circuit_get_youngest_clean_open(CIRCUIT_PURPOSE_C_GENERAL
);
665 if (get_options()->RunTesting
&&
667 circ
->timestamp_created
+ TESTING_CIRCUIT_INTERVAL
< now
) {
668 log_fn(LOG_INFO
,"Creating a new testing circuit.");
669 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, 0);
673 if (!options
->DisablePredictedCircuits
)
674 circuit_predict_and_launch_new();
677 /** If the stream <b>conn</b> is a member of any of the linked
678 * lists of <b>circ</b>, then remove it from the list.
681 circuit_detach_stream(circuit_t
*circ
, edge_connection_t
*conn
)
683 edge_connection_t
*prevconn
;
688 conn
->cpath_layer
= NULL
; /* make sure we don't keep a stale pointer */
689 conn
->on_circuit
= NULL
;
691 if (CIRCUIT_IS_ORIGIN(circ
)) {
692 origin_circuit_t
*origin_circ
= TO_ORIGIN_CIRCUIT(circ
);
693 if (conn
== origin_circ
->p_streams
) {
694 origin_circ
->p_streams
= conn
->next_stream
;
698 for (prevconn
= origin_circ
->p_streams
;
699 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
700 prevconn
= prevconn
->next_stream
)
702 if (prevconn
&& prevconn
->next_stream
) {
703 prevconn
->next_stream
= conn
->next_stream
;
707 or_circuit_t
*or_circ
= TO_OR_CIRCUIT(circ
);
708 if (conn
== or_circ
->n_streams
) {
709 or_circ
->n_streams
= conn
->next_stream
;
712 if (conn
== or_circ
->resolving_streams
) {
713 or_circ
->resolving_streams
= conn
->next_stream
;
717 for (prevconn
= or_circ
->n_streams
;
718 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
719 prevconn
= prevconn
->next_stream
)
721 if (prevconn
&& prevconn
->next_stream
) {
722 prevconn
->next_stream
= conn
->next_stream
;
726 for (prevconn
= or_circ
->resolving_streams
;
727 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
728 prevconn
= prevconn
->next_stream
)
730 if (prevconn
&& prevconn
->next_stream
) {
731 prevconn
->next_stream
= conn
->next_stream
;
736 log_warn(LD_BUG
,"Edge connection not in circuit's list.");
737 /* Don't give an error here; it's harmless. */
738 tor_fragile_assert();
741 /** If we haven't yet decided on a good timeout value for circuit
742 * building, we close idles circuits aggressively so we can get more
744 #define IDLE_TIMEOUT_WHILE_LEARNING (10*60)
746 /** Find each circuit that has been unused for too long, or dirty
747 * for too long and has no streams on it: mark it for close.
750 circuit_expire_old_circuits_clientside(void)
753 struct timeval cutoff
, now
;
755 tor_gettimeofday(&now
);
758 if (circuit_build_times_needs_circuits(&circ_times
)) {
759 /* Circuits should be shorter lived if we need more of them
760 * for learning a good build timeout */
761 cutoff
.tv_sec
-= IDLE_TIMEOUT_WHILE_LEARNING
;
763 cutoff
.tv_sec
-= get_options()->CircuitIdleTimeout
;
766 for (circ
= global_circuitlist
; circ
; circ
= circ
->next
) {
767 if (circ
->marked_for_close
|| !CIRCUIT_IS_ORIGIN(circ
))
769 /* If the circuit has been dirty for too long, and there are no streams
770 * on it, mark it for close.
772 if (circ
->timestamp_dirty
&&
773 circ
->timestamp_dirty
+ get_options()->MaxCircuitDirtiness
<
775 !TO_ORIGIN_CIRCUIT(circ
)->p_streams
/* nothing attached */ ) {
776 log_debug(LD_CIRC
, "Closing n_circ_id %d (dirty %ld sec ago, "
778 circ
->n_circ_id
, (long)(now
.tv_sec
- circ
->timestamp_dirty
),
780 circuit_mark_for_close(circ
, END_CIRC_REASON_FINISHED
);
781 } else if (!circ
->timestamp_dirty
&& circ
->state
== CIRCUIT_STATE_OPEN
) {
782 if (timercmp(&circ
->timestamp_created
, &cutoff
, <)) {
783 if (circ
->purpose
== CIRCUIT_PURPOSE_C_GENERAL
||
784 circ
->purpose
== CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
||
785 circ
->purpose
== CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
||
786 circ
->purpose
== CIRCUIT_PURPOSE_TESTING
||
787 (circ
->purpose
>= CIRCUIT_PURPOSE_C_INTRODUCING
&&
788 circ
->purpose
<= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
) ||
789 circ
->purpose
== CIRCUIT_PURPOSE_S_CONNECT_REND
) {
791 "Closing circuit that has been unused for %ld msec.",
792 tv_mdiff(&circ
->timestamp_created
, &now
));
793 circuit_mark_for_close(circ
, END_CIRC_REASON_FINISHED
);
794 } else if (!TO_ORIGIN_CIRCUIT(circ
)->is_ancient
) {
795 /* Server-side rend joined circuits can end up really old, because
796 * they are reused by clients for longer than normal. The client
797 * controls their lifespan. (They never become dirty, because
798 * connection_exit_begin_conn() never marks anything as dirty.)
799 * Similarly, server-side intro circuits last a long time. */
800 if (circ
->purpose
!= CIRCUIT_PURPOSE_S_REND_JOINED
&&
801 circ
->purpose
!= CIRCUIT_PURPOSE_S_INTRO
) {
803 "Ancient non-dirty circuit %d is still around after "
804 "%ld milliseconds. Purpose: %d (%s)",
805 TO_ORIGIN_CIRCUIT(circ
)->global_identifier
,
806 tv_mdiff(&circ
->timestamp_created
, &now
),
808 circuit_purpose_to_string(circ
->purpose
));
809 TO_ORIGIN_CIRCUIT(circ
)->is_ancient
= 1;
817 /** How long do we wait before killing circuits with the properties
820 * Probably we could choose a number here as low as 5 to 10 seconds,
821 * since these circs are used for begindir, and a) generally you either
822 * ask another begindir question right after or you don't for a long time,
823 * b) clients at least through 0.2.1.x choose from the whole set of
824 * directory mirrors at each choice, and c) re-establishing a one-hop
825 * circuit via create-fast is a light operation assuming the TLS conn is
828 * I expect "b" to go away one day when we move to using directory
829 * guards, but I think "a" and "c" are good enough reasons that a low
830 * number is safe even then.
832 #define IDLE_ONE_HOP_CIRC_TIMEOUT 60
834 /** Find each non-origin circuit that has been unused for too long,
835 * has no streams on it, used a create_fast, and ends here: mark it
839 circuit_expire_old_circuits_serverside(time_t now
)
842 or_circuit_t
*or_circ
;
843 time_t cutoff
= now
- IDLE_ONE_HOP_CIRC_TIMEOUT
;
845 for (circ
= global_circuitlist
; circ
; circ
= circ
->next
) {
846 if (circ
->marked_for_close
|| CIRCUIT_IS_ORIGIN(circ
))
848 or_circ
= TO_OR_CIRCUIT(circ
);
849 /* If the circuit has been idle for too long, and there are no streams
850 * on it, and it ends here, and it used a create_fast, mark it for close.
852 if (or_circ
->is_first_hop
&& !circ
->n_conn
&&
853 !or_circ
->n_streams
&& !or_circ
->resolving_streams
&&
855 or_circ
->p_conn
->timestamp_last_added_nonpadding
<= cutoff
) {
856 log_info(LD_CIRC
, "Closing circ_id %d (empty %d secs ago)",
858 (int)(now
- or_circ
->p_conn
->timestamp_last_added_nonpadding
));
859 circuit_mark_for_close(circ
, END_CIRC_REASON_FINISHED
);
864 /** Number of testing circuits we want open before testing our bandwidth. */
865 #define NUM_PARALLEL_TESTING_CIRCS 4
867 /** True iff we've ever had enough testing circuits open to test our
869 static int have_performed_bandwidth_test
= 0;
871 /** Reset have_performed_bandwidth_test, so we'll start building
872 * testing circuits again so we can exercise our bandwidth. */
874 reset_bandwidth_test(void)
876 have_performed_bandwidth_test
= 0;
879 /** Return 1 if we've already exercised our bandwidth, or if we
880 * have fewer than NUM_PARALLEL_TESTING_CIRCS testing circuits
881 * established or on the way. Else return 0.
884 circuit_enough_testing_circs(void)
889 if (have_performed_bandwidth_test
)
892 for (circ
= global_circuitlist
; circ
; circ
= circ
->next
) {
893 if (!circ
->marked_for_close
&& CIRCUIT_IS_ORIGIN(circ
) &&
894 circ
->purpose
== CIRCUIT_PURPOSE_TESTING
&&
895 circ
->state
== CIRCUIT_STATE_OPEN
)
898 return num
>= NUM_PARALLEL_TESTING_CIRCS
;
901 /** A testing circuit has completed. Take whatever stats we want.
902 * Noticing reachability is taken care of in onionskin_answer(),
903 * so there's no need to record anything here. But if we still want
904 * to do the bandwidth test, and we now have enough testing circuits
908 circuit_testing_opened(origin_circuit_t
*circ
)
910 if (have_performed_bandwidth_test
||
911 !check_whether_orport_reachable()) {
912 /* either we've already done everything we want with testing circuits,
913 * or this testing circuit became open due to a fluke, e.g. we picked
914 * a last hop where we already had the connection open due to an
915 * outgoing local circuit. */
916 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_AT_ORIGIN
);
917 } else if (circuit_enough_testing_circs()) {
918 router_perform_bandwidth_test(NUM_PARALLEL_TESTING_CIRCS
, time(NULL
));
919 have_performed_bandwidth_test
= 1;
921 consider_testing_reachability(1, 0);
924 /** A testing circuit has failed to build. Take whatever stats we want. */
926 circuit_testing_failed(origin_circuit_t
*circ
, int at_last_hop
)
928 if (server_mode(get_options()) && check_whether_orport_reachable())
932 "Our testing circuit (to see if your ORPort is reachable) "
933 "has failed. I'll try again later.");
935 /* These aren't used yet. */
940 /** The circuit <b>circ</b> has just become open. Take the next
941 * step: for rendezvous circuits, we pass circ to the appropriate
942 * function in rendclient or rendservice. For general circuits, we
943 * call connection_ap_attach_pending, which looks for pending streams
944 * that could use circ.
947 circuit_has_opened(origin_circuit_t
*circ
)
949 control_event_circuit_status(circ
, CIRC_EVENT_BUILT
, 0);
951 /* Remember that this circuit has finished building. Now if we start
952 * it building again later (e.g. by extending it), we will know not
953 * to consider its build time. */
954 circ
->has_opened
= 1;
956 switch (TO_CIRCUIT(circ
)->purpose
) {
957 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
958 rend_client_rendcirc_has_opened(circ
);
959 connection_ap_attach_pending();
961 case CIRCUIT_PURPOSE_C_INTRODUCING
:
962 rend_client_introcirc_has_opened(circ
);
964 case CIRCUIT_PURPOSE_C_GENERAL
:
965 /* Tell any AP connections that have been waiting for a new
966 * circuit that one is ready. */
967 connection_ap_attach_pending();
969 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
970 /* at Bob, waiting for introductions */
971 rend_service_intro_has_opened(circ
);
973 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
974 /* at Bob, connecting to rend point */
975 rend_service_rendezvous_has_opened(circ
);
977 case CIRCUIT_PURPOSE_TESTING
:
978 circuit_testing_opened(circ
);
981 * This won't happen in normal operation, but might happen if the
982 * controller did it. Just let it slide. */
986 /** Called whenever a circuit could not be successfully built.
989 circuit_build_failed(origin_circuit_t
*circ
)
991 /* we should examine circ and see if it failed because of
992 * the last hop or an earlier hop. then use this info below.
994 int failed_at_last_hop
= 0;
995 /* If the last hop isn't open, and the second-to-last is, we failed
996 * at the last hop. */
998 circ
->cpath
->prev
->state
!= CPATH_STATE_OPEN
&&
999 circ
->cpath
->prev
->prev
->state
== CPATH_STATE_OPEN
) {
1000 failed_at_last_hop
= 1;
1003 circ
->cpath
->state
!= CPATH_STATE_OPEN
) {
1004 /* We failed at the first hop. If there's an OR connection
1005 * to blame, blame it. Also, avoid this relay for a while, and
1006 * fail any one-hop directory fetches destined for it. */
1007 const char *n_conn_id
= circ
->cpath
->extend_info
->identity_digest
;
1008 int already_marked
= 0;
1009 if (circ
->_base
.n_conn
) {
1010 or_connection_t
*n_conn
= circ
->_base
.n_conn
;
1011 if (n_conn
->is_bad_for_new_circs
) {
1012 /* We only want to blame this router when a fresh healthy
1013 * connection fails. So don't mark this router as newly failed,
1014 * since maybe this was just an old circuit attempt that's
1015 * finally timing out now. Also, there's no need to blow away
1016 * circuits/streams/etc, since the failure of an unhealthy conn
1017 * doesn't tell us much about whether a healthy conn would
1022 "Our circuit failed to get a response from the first hop "
1023 "(%s:%d). I'm going to try to rotate to a better connection.",
1024 n_conn
->_base
.address
, n_conn
->_base
.port
);
1025 n_conn
->is_bad_for_new_circs
= 1;
1028 "Our circuit died before the first hop with no connection");
1030 if (n_conn_id
&& !already_marked
) {
1031 entry_guard_register_connect_status(n_conn_id
, 0, 1, time(NULL
));
1032 /* if there are any one-hop streams waiting on this circuit, fail
1033 * them now so they can retry elsewhere. */
1034 connection_ap_fail_onehop(n_conn_id
, circ
->build_state
);
1038 switch (circ
->_base
.purpose
) {
1039 case CIRCUIT_PURPOSE_C_GENERAL
:
1040 /* If we never built the circuit, note it as a failure. */
1041 circuit_increment_failure_count();
1042 if (failed_at_last_hop
) {
1043 /* Make sure any streams that demand our last hop as their exit
1044 * know that it's unlikely to happen. */
1045 circuit_discard_optional_exit_enclaves(circ
->cpath
->prev
->extend_info
);
1048 case CIRCUIT_PURPOSE_TESTING
:
1049 circuit_testing_failed(circ
, failed_at_last_hop
);
1051 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
1052 /* at Bob, waiting for introductions */
1053 if (circ
->_base
.state
!= CIRCUIT_STATE_OPEN
) {
1054 circuit_increment_failure_count();
1056 /* no need to care here, because bob will rebuild intro
1057 * points periodically. */
1059 case CIRCUIT_PURPOSE_C_INTRODUCING
:
1060 /* at Alice, connecting to intro point */
1061 /* Don't increment failure count, since Bob may have picked
1062 * the introduction point maliciously */
1063 /* Alice will pick a new intro point when this one dies, if
1064 * the stream in question still cares. No need to act here. */
1066 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
1067 /* at Alice, waiting for Bob */
1068 circuit_increment_failure_count();
1069 /* Alice will pick a new rend point when this one dies, if
1070 * the stream in question still cares. No need to act here. */
1072 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
1073 /* at Bob, connecting to rend point */
1074 /* Don't increment failure count, since Alice may have picked
1075 * the rendezvous point maliciously */
1077 "Couldn't connect to Alice's chosen rend point %s "
1079 escaped(build_state_get_exit_nickname(circ
->build_state
)),
1080 failed_at_last_hop
?"last":"non-last");
1081 rend_service_relaunch_rendezvous(circ
);
1084 * This won't happen in normal operation, but might happen if the
1085 * controller did it. Just let it slide. */
1089 /** Number of consecutive failures so far; should only be touched by
1090 * circuit_launch_new and circuit_*_failure_count.
1092 static int n_circuit_failures
= 0;
1093 /** Before the last time we called circuit_reset_failure_count(), were
1094 * there a lot of failures? */
1095 static int did_circs_fail_last_period
= 0;
1097 /** Don't retry launching a new circuit if we try this many times with no
1099 #define MAX_CIRCUIT_FAILURES 5
1101 /** Launch a new circuit; see circuit_launch_by_extend_info() for
1102 * details on arguments. */
1104 circuit_launch_by_router(uint8_t purpose
,
1105 routerinfo_t
*exit
, int flags
)
1107 origin_circuit_t
*circ
;
1108 extend_info_t
*info
= NULL
;
1110 info
= extend_info_from_router(exit
);
1111 circ
= circuit_launch_by_extend_info(purpose
, info
, flags
);
1113 extend_info_free(info
);
1117 /** Launch a new circuit with purpose <b>purpose</b> and exit node
1118 * <b>extend_info</b> (or NULL to select a random exit node). If flags
1119 * contains CIRCLAUNCH_NEED_UPTIME, choose among routers with high uptime. If
1120 * CIRCLAUNCH_NEED_CAPACITY is set, choose among routers with high bandwidth.
1121 * If CIRCLAUNCH_IS_INTERNAL is true, the last hop need not be an exit node.
1122 * If CIRCLAUNCH_ONEHOP_TUNNEL is set, the circuit will have only one hop.
1123 * Return the newly allocated circuit on success, or NULL on failure. */
1125 circuit_launch_by_extend_info(uint8_t purpose
,
1126 extend_info_t
*extend_info
,
1129 origin_circuit_t
*circ
;
1130 int onehop_tunnel
= (flags
& CIRCLAUNCH_ONEHOP_TUNNEL
) != 0;
1132 if (!onehop_tunnel
&& !router_have_minimum_dir_info()) {
1133 log_debug(LD_CIRC
,"Haven't fetched enough directory info yet; canceling "
1138 if ((extend_info
|| purpose
!= CIRCUIT_PURPOSE_C_GENERAL
) &&
1139 purpose
!= CIRCUIT_PURPOSE_TESTING
&& !onehop_tunnel
) {
1140 /* see if there are appropriate circs available to cannibalize. */
1141 /* XXX if we're planning to add a hop, perhaps we want to look for
1142 * internal circs rather than exit circs? -RD */
1143 circ
= circuit_find_to_cannibalize(purpose
, extend_info
, flags
);
1145 log_info(LD_CIRC
,"Cannibalizing circ '%s' for purpose %d (%s)",
1146 build_state_get_exit_nickname(circ
->build_state
), purpose
,
1147 circuit_purpose_to_string(purpose
));
1148 circ
->_base
.purpose
= purpose
;
1149 /* reset the birth date of this circ, else expire_building
1150 * will see it and think it's been trying to build since it
1152 tor_gettimeofday(&circ
->_base
.timestamp_created
);
1154 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
1155 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
1156 /* it's ready right now */
1158 case CIRCUIT_PURPOSE_C_INTRODUCING
:
1159 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
1160 case CIRCUIT_PURPOSE_C_GENERAL
:
1161 /* need to add a new hop */
1162 tor_assert(extend_info
);
1163 if (circuit_extend_to_new_exit(circ
, extend_info
) < 0)
1168 "unexpected purpose %d when cannibalizing a circ.",
1170 tor_fragile_assert();
1177 if (did_circs_fail_last_period
&&
1178 n_circuit_failures
> MAX_CIRCUIT_FAILURES
) {
1179 /* too many failed circs in a row. don't try. */
1180 // log_fn(LOG_INFO,"%d failures so far, not trying.",n_circuit_failures);
1184 /* try a circ. if it fails, circuit_mark_for_close will increment
1185 * n_circuit_failures */
1186 return circuit_establish_circuit(purpose
, extend_info
, flags
);
1189 /** Record another failure at opening a general circuit. When we have
1190 * too many, we'll stop trying for the remainder of this minute.
1193 circuit_increment_failure_count(void)
1195 ++n_circuit_failures
;
1196 log_debug(LD_CIRC
,"n_circuit_failures now %d.",n_circuit_failures
);
1199 /** Reset the failure count for opening general circuits. This means
1200 * we will try MAX_CIRCUIT_FAILURES times more (if necessary) before
1204 circuit_reset_failure_count(int timeout
)
1206 if (timeout
&& n_circuit_failures
> MAX_CIRCUIT_FAILURES
)
1207 did_circs_fail_last_period
= 1;
1209 did_circs_fail_last_period
= 0;
1210 n_circuit_failures
= 0;
1213 /** Find an open circ that we're happy to use for <b>conn</b> and return 1. If
1214 * there isn't one, and there isn't one on the way, launch one and return
1215 * 0. If it will never work, return -1.
1217 * Write the found or in-progress or launched circ into *circp.
1220 circuit_get_open_circ_or_launch(edge_connection_t
*conn
,
1221 uint8_t desired_circuit_purpose
,
1222 origin_circuit_t
**circp
)
1224 origin_circuit_t
*circ
;
1225 int check_exit_policy
;
1226 int need_uptime
, need_internal
;
1228 or_options_t
*options
= get_options();
1232 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
);
1234 conn
->socks_request
->command
== SOCKS_COMMAND_CONNECT
&&
1235 !conn
->use_begindir
&&
1236 !connection_edge_is_rendezvous_stream(conn
);
1237 want_onehop
= conn
->want_onehop
;
1239 need_uptime
= !conn
->want_onehop
&& !conn
->use_begindir
&&
1240 smartlist_string_num_isin(options
->LongLivedPorts
,
1241 conn
->socks_request
->port
);
1242 need_internal
= desired_circuit_purpose
!= CIRCUIT_PURPOSE_C_GENERAL
;
1244 circ
= circuit_get_best(conn
, 1, desired_circuit_purpose
,
1245 need_uptime
, need_internal
);
1249 return 1; /* we're happy */
1252 if (!want_onehop
&& !router_have_minimum_dir_info()) {
1253 if (!connection_get_by_type(CONN_TYPE_DIR
)) {
1254 int severity
= LOG_NOTICE
;
1255 /* FFFF if this is a tunneled directory fetch, don't yell
1256 * as loudly. the user doesn't even know it's happening. */
1257 if (entry_list_is_constrained(options
) &&
1258 entries_known_but_down(options
)) {
1259 log_fn(severity
, LD_APP
|LD_DIR
,
1260 "Application request when we haven't used client functionality "
1261 "lately. Optimistically trying known %s again.",
1262 options
->UseBridges
? "bridges" : "entrynodes");
1263 entries_retry_all(options
);
1264 } else if (!options
->UseBridges
|| any_bridge_descriptors_known()) {
1265 log_fn(severity
, LD_APP
|LD_DIR
,
1266 "Application request when we haven't used client functionality "
1267 "lately. Optimistically trying directory fetches again.");
1268 routerlist_retry_directory_downloads(time(NULL
));
1271 /* the stream will be dealt with when router_have_minimum_dir_info becomes
1272 * 1, or when all directory attempts fail and directory_all_unreachable()
1278 /* Do we need to check exit policy? */
1279 if (check_exit_policy
) {
1280 if (!conn
->chosen_exit_name
) {
1283 if (tor_inet_aton(conn
->socks_request
->address
, &in
))
1284 addr
= ntohl(in
.s_addr
);
1285 if (router_exit_policy_all_routers_reject(addr
,
1286 conn
->socks_request
->port
,
1289 "No Tor server allows exit to %s:%d. Rejecting.",
1290 safe_str_client(conn
->socks_request
->address
),
1291 conn
->socks_request
->port
);
1295 /* XXXX023 Duplicates checks in connection_ap_handshake_attach_circuit:
1296 * refactor into a single function? */
1297 routerinfo_t
*router
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1298 int opt
= conn
->chosen_exit_optional
;
1299 if (router
&& !connection_ap_can_use_exit(conn
, router
)) {
1300 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1301 "Requested exit point '%s' is excluded or "
1302 "would refuse request. %s.",
1303 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1305 conn
->chosen_exit_optional
= 0;
1306 tor_free(conn
->chosen_exit_name
);
1308 return circuit_get_open_circ_or_launch(conn
,
1309 desired_circuit_purpose
,
1317 /* is one already on the way? */
1318 circ
= circuit_get_best(conn
, 0, desired_circuit_purpose
,
1319 need_uptime
, need_internal
);
1321 log_debug(LD_CIRC
, "one on the way!");
1323 extend_info_t
*extend_info
=NULL
;
1324 uint8_t new_circ_purpose
;
1326 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
) {
1327 /* need to pick an intro point */
1328 tor_assert(conn
->rend_data
);
1329 extend_info
= rend_client_get_random_intro(conn
->rend_data
);
1332 "No intro points for '%s': re-fetching service descriptor.",
1333 safe_str_client(conn
->rend_data
->onion_address
));
1334 rend_client_refetch_v2_renddesc(conn
->rend_data
);
1335 conn
->_base
.state
= AP_CONN_STATE_RENDDESC_WAIT
;
1338 log_info(LD_REND
,"Chose '%s' as intro point for '%s'.",
1339 extend_info
->nickname
,
1340 safe_str_client(conn
->rend_data
->onion_address
));
1343 /* If we have specified a particular exit node for our
1344 * connection, then be sure to open a circuit to that exit node.
1346 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_GENERAL
) {
1347 if (conn
->chosen_exit_name
) {
1349 int opt
= conn
->chosen_exit_optional
;
1350 r
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1352 extend_info
= extend_info_from_router(r
);
1354 log_debug(LD_DIR
, "considering %d, %s",
1355 want_onehop
, conn
->chosen_exit_name
);
1356 if (want_onehop
&& conn
->chosen_exit_name
[0] == '$') {
1357 /* We're asking for a one-hop circuit to a router that
1358 * we don't have a routerinfo about. Make up an extend_info. */
1359 char digest
[DIGEST_LEN
];
1360 char *hexdigest
= conn
->chosen_exit_name
+1;
1362 if (strlen(hexdigest
) < HEX_DIGEST_LEN
||
1363 base16_decode(digest
,DIGEST_LEN
,hexdigest
,HEX_DIGEST_LEN
)<0) {
1364 log_info(LD_DIR
, "Broken exit digest on tunnel conn. Closing.");
1367 if (tor_addr_from_str(&addr
, conn
->socks_request
->address
) < 0) {
1368 log_info(LD_DIR
, "Broken address %s on tunnel conn. Closing.",
1369 escaped_safe_str_client(conn
->socks_request
->address
));
1372 extend_info
= extend_info_alloc(conn
->chosen_exit_name
+1,
1373 digest
, NULL
, &addr
,
1374 conn
->socks_request
->port
);
1376 /* We will need an onion key for the router, and we
1377 * don't have one. Refuse or relax requirements. */
1378 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1379 "Requested exit point '%s' is not known. %s.",
1380 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1382 conn
->chosen_exit_optional
= 0;
1383 tor_free(conn
->chosen_exit_name
);
1384 /* Try again with no requested exit */
1385 return circuit_get_open_circ_or_launch(conn
,
1386 desired_circuit_purpose
,
1395 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_REND_JOINED
)
1396 new_circ_purpose
= CIRCUIT_PURPOSE_C_ESTABLISH_REND
;
1397 else if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
)
1398 new_circ_purpose
= CIRCUIT_PURPOSE_C_INTRODUCING
;
1400 new_circ_purpose
= desired_circuit_purpose
;
1403 int flags
= CIRCLAUNCH_NEED_CAPACITY
;
1404 if (want_onehop
) flags
|= CIRCLAUNCH_ONEHOP_TUNNEL
;
1405 if (need_uptime
) flags
|= CIRCLAUNCH_NEED_UPTIME
;
1406 if (need_internal
) flags
|= CIRCLAUNCH_IS_INTERNAL
;
1407 circ
= circuit_launch_by_extend_info(new_circ_purpose
, extend_info
,
1411 extend_info_free(extend_info
);
1413 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_GENERAL
) {
1414 /* We just caused a circuit to get built because of this stream.
1415 * If this stream has caused a _lot_ of circuits to be built, that's
1416 * a bad sign: we should tell the user. */
1417 if (conn
->num_circuits_launched
< NUM_CIRCUITS_LAUNCHED_THRESHOLD
&&
1418 ++conn
->num_circuits_launched
== NUM_CIRCUITS_LAUNCHED_THRESHOLD
)
1419 log_warn(LD_BUG
, "The application request to %s:%d has launched "
1420 "%d circuits without finding one it likes.",
1421 escaped_safe_str_client(conn
->socks_request
->address
),
1422 conn
->socks_request
->port
,
1423 conn
->num_circuits_launched
);
1425 /* help predict this next time */
1426 rep_hist_note_used_internal(time(NULL
), need_uptime
, 1);
1428 /* write the service_id into circ */
1429 circ
->rend_data
= rend_data_dup(conn
->rend_data
);
1430 if (circ
->_base
.purpose
== CIRCUIT_PURPOSE_C_ESTABLISH_REND
&&
1431 circ
->_base
.state
== CIRCUIT_STATE_OPEN
)
1432 rend_client_rendcirc_has_opened(circ
);
1438 "No safe circuit (purpose %d) ready for edge "
1439 "connection; delaying.",
1440 desired_circuit_purpose
);
1445 /** Return true iff <b>crypt_path</b> is one of the crypt_paths for
1448 cpath_is_on_circuit(origin_circuit_t
*circ
, crypt_path_t
*crypt_path
)
1450 crypt_path_t
*cpath
, *cpath_next
= NULL
;
1451 for (cpath
= circ
->cpath
; cpath_next
!= circ
->cpath
; cpath
= cpath_next
) {
1452 cpath_next
= cpath
->next
;
1453 if (crypt_path
== cpath
)
1459 /** Attach the AP stream <b>apconn</b> to circ's linked list of
1460 * p_streams. Also set apconn's cpath_layer to <b>cpath</b>, or to the last
1461 * hop in circ's cpath if <b>cpath</b> is NULL.
1464 link_apconn_to_circ(edge_connection_t
*apconn
, origin_circuit_t
*circ
,
1465 crypt_path_t
*cpath
)
1467 /* add it into the linked list of streams on this circuit */
1468 log_debug(LD_APP
|LD_CIRC
, "attaching new conn to circ. n_circ_id %d.",
1469 circ
->_base
.n_circ_id
);
1470 /* reset it, so we can measure circ timeouts */
1471 apconn
->_base
.timestamp_lastread
= time(NULL
);
1472 apconn
->next_stream
= circ
->p_streams
;
1473 apconn
->on_circuit
= TO_CIRCUIT(circ
);
1474 /* assert_connection_ok(conn, time(NULL)); */
1475 circ
->p_streams
= apconn
;
1477 if (cpath
) { /* we were given one; use it */
1478 tor_assert(cpath_is_on_circuit(circ
, cpath
));
1479 apconn
->cpath_layer
= cpath
;
1480 } else { /* use the last hop in the circuit */
1481 tor_assert(circ
->cpath
);
1482 tor_assert(circ
->cpath
->prev
);
1483 tor_assert(circ
->cpath
->prev
->state
== CPATH_STATE_OPEN
);
1484 apconn
->cpath_layer
= circ
->cpath
->prev
;
1488 /** If an exit wasn't specifically chosen, save the history for future
1491 consider_recording_trackhost(edge_connection_t
*conn
, origin_circuit_t
*circ
)
1493 int found_needle
= 0;
1494 or_options_t
*options
= get_options();
1497 char fp
[HEX_DIGEST_LEN
+1];
1499 /* Search the addressmap for this conn's destination. */
1500 /* If he's not in the address map.. */
1501 if (!options
->TrackHostExits
||
1502 addressmap_have_mapping(conn
->socks_request
->address
,
1503 options
->TrackHostExitsExpire
))
1504 return; /* nothing to track, or already mapped */
1506 SMARTLIST_FOREACH(options
->TrackHostExits
, const char *, cp
, {
1507 if (cp
[0] == '.') { /* match end */
1508 if (cp
[1] == '\0' ||
1509 !strcasecmpend(conn
->socks_request
->address
, cp
) ||
1510 !strcasecmp(conn
->socks_request
->address
, &cp
[1]))
1512 } else if (strcasecmp(cp
, conn
->socks_request
->address
) == 0) {
1517 if (!found_needle
|| !circ
->build_state
->chosen_exit
)
1520 /* write down the fingerprint of the chosen exit, not the nickname,
1521 * because the chosen exit might not be named. */
1522 base16_encode(fp
, sizeof(fp
),
1523 circ
->build_state
->chosen_exit
->identity_digest
, DIGEST_LEN
);
1525 /* Add this exit/hostname pair to the addressmap. */
1526 len
= strlen(conn
->socks_request
->address
) + 1 /* '.' */ +
1527 strlen(fp
) + 1 /* '.' */ +
1528 strlen("exit") + 1 /* '\0' */;
1529 new_address
= tor_malloc(len
);
1531 tor_snprintf(new_address
, len
, "%s.%s.exit",
1532 conn
->socks_request
->address
, fp
);
1534 addressmap_register(conn
->socks_request
->address
, new_address
,
1535 time(NULL
) + options
->TrackHostExitsExpire
,
1536 ADDRMAPSRC_TRACKEXIT
);
1539 /** Attempt to attach the connection <b>conn</b> to <b>circ</b>, and send a
1540 * begin or resolve cell as appropriate. Return values are as for
1541 * connection_ap_handshake_attach_circuit. The stream will exit from the hop
1542 * indicated by <b>cpath</b>, or from the last hop in circ's cpath if
1543 * <b>cpath</b> is NULL. */
1545 connection_ap_handshake_attach_chosen_circuit(edge_connection_t
*conn
,
1546 origin_circuit_t
*circ
,
1547 crypt_path_t
*cpath
)
1550 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
||
1551 conn
->_base
.state
== AP_CONN_STATE_CONTROLLER_WAIT
);
1552 tor_assert(conn
->socks_request
);
1554 tor_assert(circ
->_base
.state
== CIRCUIT_STATE_OPEN
);
1556 conn
->_base
.state
= AP_CONN_STATE_CIRCUIT_WAIT
;
1558 if (!circ
->_base
.timestamp_dirty
)
1559 circ
->_base
.timestamp_dirty
= time(NULL
);
1561 link_apconn_to_circ(conn
, circ
, cpath
);
1562 tor_assert(conn
->socks_request
);
1563 if (conn
->socks_request
->command
== SOCKS_COMMAND_CONNECT
) {
1564 if (!conn
->use_begindir
)
1565 consider_recording_trackhost(conn
, circ
);
1566 if (connection_ap_handshake_send_begin(conn
) < 0)
1569 if (connection_ap_handshake_send_resolve(conn
) < 0)
1576 /** Try to find a safe live circuit for CONN_TYPE_AP connection conn. If
1577 * we don't find one: if conn cannot be handled by any known nodes,
1578 * warn and return -1 (conn needs to die, and is maybe already marked);
1579 * else launch new circuit (if necessary) and return 0.
1580 * Otherwise, associate conn with a safe live circuit, do the
1581 * right next step, and return 1.
1583 /* XXXX this function should mark for close whenever it returns -1;
1584 * its callers shouldn't have to worry about that. */
1586 connection_ap_handshake_attach_circuit(edge_connection_t
*conn
)
1593 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
);
1594 tor_assert(conn
->socks_request
);
1595 want_onehop
= conn
->want_onehop
;
1597 conn_age
= (int)(time(NULL
) - conn
->_base
.timestamp_created
);
1599 if (conn_age
>= get_options()->SocksTimeout
) {
1600 int severity
= (tor_addr_is_null(&conn
->_base
.addr
) && !conn
->_base
.port
) ?
1601 LOG_INFO
: LOG_NOTICE
;
1602 log_fn(severity
, LD_APP
,
1603 "Tried for %d seconds to get a connection to %s:%d. Giving up.",
1604 conn_age
, safe_str_client(conn
->socks_request
->address
),
1605 conn
->socks_request
->port
);
1609 if (!connection_edge_is_rendezvous_stream(conn
)) { /* we're a general conn */
1610 origin_circuit_t
*circ
=NULL
;
1612 if (conn
->chosen_exit_name
) {
1613 routerinfo_t
*router
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1614 int opt
= conn
->chosen_exit_optional
;
1615 if (!router
&& !want_onehop
) {
1616 /* We ran into this warning when trying to extend a circuit to a
1617 * hidden service directory for which we didn't have a router
1618 * descriptor. See flyspray task 767 for more details. We should
1619 * keep this in mind when deciding to use BEGIN_DIR cells for other
1620 * directory requests as well. -KL*/
1621 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1622 "Requested exit point '%s' is not known. %s.",
1623 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1625 conn
->chosen_exit_optional
= 0;
1626 tor_free(conn
->chosen_exit_name
);
1631 if (router
&& !connection_ap_can_use_exit(conn
, router
)) {
1632 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1633 "Requested exit point '%s' is excluded or "
1634 "would refuse request. %s.",
1635 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1637 conn
->chosen_exit_optional
= 0;
1638 tor_free(conn
->chosen_exit_name
);
1645 /* find the circuit that we should use, if there is one. */
1646 retval
= circuit_get_open_circ_or_launch(
1647 conn
, CIRCUIT_PURPOSE_C_GENERAL
, &circ
);
1648 if (retval
< 1) // XXX022 if we totally fail, this still returns 0 -RD
1651 log_debug(LD_APP
|LD_CIRC
,
1652 "Attaching apconn to circ %d (stream %d sec old).",
1653 circ
->_base
.n_circ_id
, conn_age
);
1654 /* print the circ's path, so people can figure out which circs are
1656 circuit_log_path(LOG_INFO
,LD_APP
|LD_CIRC
,circ
);
1658 /* We have found a suitable circuit for our conn. Hurray. */
1659 return connection_ap_handshake_attach_chosen_circuit(conn
, circ
, NULL
);
1661 } else { /* we're a rendezvous conn */
1662 origin_circuit_t
*rendcirc
=NULL
, *introcirc
=NULL
;
1664 tor_assert(!conn
->cpath_layer
);
1666 /* start by finding a rendezvous circuit for us */
1668 retval
= circuit_get_open_circ_or_launch(
1669 conn
, CIRCUIT_PURPOSE_C_REND_JOINED
, &rendcirc
);
1670 if (retval
< 0) return -1; /* failed */
1673 tor_assert(rendcirc
);
1674 /* one is already established, attach */
1676 "rend joined circ %d already here. attaching. "
1677 "(stream %d sec old)",
1678 rendcirc
->_base
.n_circ_id
, conn_age
);
1679 /* Mark rendezvous circuits as 'newly dirty' every time you use
1680 * them, since the process of rebuilding a rendezvous circ is so
1681 * expensive. There is a tradeoff between linkability and
1682 * feasibility, at this point.
1684 rendcirc
->_base
.timestamp_dirty
= time(NULL
);
1685 link_apconn_to_circ(conn
, rendcirc
, NULL
);
1686 if (connection_ap_handshake_send_begin(conn
) < 0)
1687 return 0; /* already marked, let them fade away */
1691 if (rendcirc
&& (rendcirc
->_base
.purpose
==
1692 CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
)) {
1694 "pending-join circ %d already here, with intro ack. "
1695 "Stalling. (stream %d sec old)",
1696 rendcirc
->_base
.n_circ_id
, conn_age
);
1700 /* it's on its way. find an intro circ. */
1701 retval
= circuit_get_open_circ_or_launch(
1702 conn
, CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
, &introcirc
);
1703 if (retval
< 0) return -1; /* failed */
1706 /* one has already sent the intro. keep waiting. */
1707 circuit_t
*c
= NULL
;
1708 tor_assert(introcirc
);
1709 log_info(LD_REND
, "Intro circ %d present and awaiting ack (rend %d). "
1710 "Stalling. (stream %d sec old)",
1711 introcirc
->_base
.n_circ_id
,
1712 rendcirc
? rendcirc
->_base
.n_circ_id
: 0,
1714 /* abort parallel intro circs, if any */
1715 for (c
= global_circuitlist
; c
; c
= c
->next
) {
1716 if (c
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
&&
1717 !c
->marked_for_close
&& CIRCUIT_IS_ORIGIN(c
)) {
1718 origin_circuit_t
*oc
= TO_ORIGIN_CIRCUIT(c
);
1719 if (oc
->rend_data
&&
1720 !rend_cmp_service_ids(conn
->rend_data
->onion_address
,
1721 oc
->rend_data
->onion_address
)) {
1722 log_info(LD_REND
|LD_CIRC
, "Closing introduction circuit that we "
1723 "built in parallel.");
1724 circuit_mark_for_close(c
, END_CIRC_REASON_TIMEOUT
);
1731 /* now rendcirc and introcirc are each either undefined or not finished */
1733 if (rendcirc
&& introcirc
&&
1734 rendcirc
->_base
.purpose
== CIRCUIT_PURPOSE_C_REND_READY
) {
1736 "ready rend circ %d already here (no intro-ack yet on "
1737 "intro %d). (stream %d sec old)",
1738 rendcirc
->_base
.n_circ_id
,
1739 introcirc
->_base
.n_circ_id
, conn_age
);
1741 tor_assert(introcirc
->_base
.purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
);
1742 if (introcirc
->_base
.state
== CIRCUIT_STATE_OPEN
) {
1743 log_info(LD_REND
,"found open intro circ %d (rend %d); sending "
1744 "introduction. (stream %d sec old)",
1745 introcirc
->_base
.n_circ_id
, rendcirc
->_base
.n_circ_id
,
1747 switch (rend_client_send_introduction(introcirc
, rendcirc
)) {
1748 case 0: /* success */
1749 rendcirc
->_base
.timestamp_dirty
= time(NULL
);
1750 introcirc
->_base
.timestamp_dirty
= time(NULL
);
1751 assert_circuit_ok(TO_CIRCUIT(rendcirc
));
1752 assert_circuit_ok(TO_CIRCUIT(introcirc
));
1754 case -1: /* transient error */
1756 case -2: /* permanent error */
1759 tor_fragile_assert();
1765 log_info(LD_REND
, "Intro (%d) and rend (%d) circs are not both ready. "
1766 "Stalling conn. (%d sec old)",
1767 introcirc
? introcirc
->_base
.n_circ_id
: 0,
1768 rendcirc
? rendcirc
->_base
.n_circ_id
: 0, conn_age
);