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) 2007-2010, The Tor Project, Inc. */
5 /* See LICENSE for licensing information */
9 * \brief Launch the right sort of circuits and attach streams to them.
14 /********* START VARIABLES **********/
16 extern circuit_t
*global_circuitlist
; /* from circuitlist.c */
18 /********* END VARIABLES ************/
20 static void circuit_expire_old_circuits_clientside(time_t now
);
21 static void circuit_increment_failure_count(void);
23 long int lround(double x
);
25 /** Return 1 if <b>circ</b> could be returned by circuit_get_best().
29 circuit_is_acceptable(circuit_t
*circ
, edge_connection_t
*conn
,
30 int must_be_open
, uint8_t purpose
,
31 int need_uptime
, int need_internal
,
34 routerinfo_t
*exitrouter
;
35 cpath_build_state_t
*build_state
;
38 tor_assert(conn
->socks_request
);
40 if (!CIRCUIT_IS_ORIGIN(circ
))
41 return 0; /* this circ doesn't start at us */
42 if (must_be_open
&& (circ
->state
!= CIRCUIT_STATE_OPEN
|| !circ
->n_conn
))
43 return 0; /* ignore non-open circs */
44 if (circ
->marked_for_close
)
47 /* if this circ isn't our purpose, skip. */
48 if (purpose
== CIRCUIT_PURPOSE_C_REND_JOINED
&& !must_be_open
) {
49 if (circ
->purpose
!= CIRCUIT_PURPOSE_C_ESTABLISH_REND
&&
50 circ
->purpose
!= CIRCUIT_PURPOSE_C_REND_READY
&&
51 circ
->purpose
!= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
&&
52 circ
->purpose
!= CIRCUIT_PURPOSE_C_REND_JOINED
)
54 } else if (purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
&&
56 if (circ
->purpose
!= CIRCUIT_PURPOSE_C_INTRODUCING
&&
57 circ
->purpose
!= CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
)
60 if (purpose
!= circ
->purpose
)
64 if (purpose
== CIRCUIT_PURPOSE_C_GENERAL
)
65 if (circ
->timestamp_dirty
&&
66 circ
->timestamp_dirty
+get_options()->MaxCircuitDirtiness
<= now
)
69 /* decide if this circ is suitable for this conn */
71 /* for rend circs, circ->cpath->prev is not the last router in the
72 * circuit, it's the magical extra bob hop. so just check the nickname
73 * of the one we meant to finish at.
75 build_state
= TO_ORIGIN_CIRCUIT(circ
)->build_state
;
76 exitrouter
= build_state_get_exit_router(build_state
);
78 if (need_uptime
&& !build_state
->need_uptime
)
80 if (need_internal
!= build_state
->is_internal
)
83 if (purpose
== CIRCUIT_PURPOSE_C_GENERAL
) {
84 if (!exitrouter
&& !build_state
->onehop_tunnel
) {
85 log_debug(LD_CIRC
,"Not considering circuit with unknown router.");
86 return 0; /* this circuit is screwed and doesn't know it yet,
87 * or is a rendezvous circuit. */
89 if (build_state
->onehop_tunnel
) {
90 if (!conn
->want_onehop
) {
91 log_debug(LD_CIRC
,"Skipping one-hop circuit.");
94 tor_assert(conn
->chosen_exit_name
);
95 if (build_state
->chosen_exit
) {
96 char digest
[DIGEST_LEN
];
97 if (hexdigest_to_digest(conn
->chosen_exit_name
, digest
) < 0)
98 return 0; /* broken digest, we don't want it */
99 if (memcmp(digest
, build_state
->chosen_exit
->identity_digest
,
101 return 0; /* this is a circuit to somewhere else */
102 if (tor_digest_is_zero(digest
)) {
103 /* we don't know the digest; have to compare addr:port */
105 int r
= tor_addr_from_str(&addr
, conn
->socks_request
->address
);
107 !tor_addr_eq(&build_state
->chosen_exit
->addr
, &addr
) ||
108 build_state
->chosen_exit
->port
!= conn
->socks_request
->port
)
113 if (conn
->want_onehop
) {
114 /* don't use three-hop circuits -- that could hurt our anonymity. */
118 if (exitrouter
&& !connection_ap_can_use_exit(conn
, exitrouter
, 0)) {
119 /* can't exit from this router */
122 } else { /* not general */
123 origin_circuit_t
*ocirc
= TO_ORIGIN_CIRCUIT(circ
);
124 if ((conn
->rend_data
&& !ocirc
->rend_data
) ||
125 (!conn
->rend_data
&& ocirc
->rend_data
) ||
126 (conn
->rend_data
&& ocirc
->rend_data
&&
127 rend_cmp_service_ids(conn
->rend_data
->onion_address
,
128 ocirc
->rend_data
->onion_address
))) {
129 /* this circ is not for this conn */
136 /** Return 1 if circuit <b>a</b> is better than circuit <b>b</b> for
137 * <b>purpose</b>, and return 0 otherwise. Used by circuit_get_best.
140 circuit_is_better(circuit_t
*a
, circuit_t
*b
, uint8_t purpose
)
143 case CIRCUIT_PURPOSE_C_GENERAL
:
144 /* if it's used but less dirty it's best;
145 * else if it's more recently created it's best
147 if (b
->timestamp_dirty
) {
148 if (a
->timestamp_dirty
&&
149 a
->timestamp_dirty
> b
->timestamp_dirty
)
152 if (a
->timestamp_dirty
||
153 a
->timestamp_created
> b
->timestamp_created
)
155 if (CIRCUIT_IS_ORIGIN(b
) &&
156 TO_ORIGIN_CIRCUIT(b
)->build_state
->is_internal
)
160 case CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
:
161 /* the closer it is to ack_wait the better it is */
162 if (a
->purpose
> b
->purpose
)
165 case CIRCUIT_PURPOSE_C_REND_JOINED
:
166 /* the closer it is to rend_joined the better it is */
167 if (a
->purpose
> b
->purpose
)
174 /** Find the best circ that conn can use, preferably one which is
175 * dirty. Circ must not be too old.
177 * Conn must be defined.
179 * If must_be_open, ignore circs not in CIRCUIT_STATE_OPEN.
181 * circ_purpose specifies what sort of circuit we must have.
182 * It can be C_GENERAL, C_INTRODUCE_ACK_WAIT, or C_REND_JOINED.
184 * If it's REND_JOINED and must_be_open==0, then return the closest
185 * rendezvous-purposed circuit that you can find.
187 * If it's INTRODUCE_ACK_WAIT and must_be_open==0, then return the
188 * closest introduce-purposed circuit that you can find.
190 static origin_circuit_t
*
191 circuit_get_best(edge_connection_t
*conn
, int must_be_open
, uint8_t purpose
,
192 int need_uptime
, int need_internal
)
194 circuit_t
*circ
, *best
=NULL
;
195 time_t now
= time(NULL
);
196 int intro_going_on_but_too_old
= 0;
200 tor_assert(purpose
== CIRCUIT_PURPOSE_C_GENERAL
||
201 purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
||
202 purpose
== CIRCUIT_PURPOSE_C_REND_JOINED
);
204 for (circ
=global_circuitlist
;circ
;circ
= circ
->next
) {
205 if (!circuit_is_acceptable(circ
,conn
,must_be_open
,purpose
,
206 need_uptime
,need_internal
,now
))
209 /* XXX022 make this 15 be a function of circuit finishing times we've
210 * seen lately, a la Fallon Chen's GSoC work -RD */
211 #define REND_PARALLEL_INTRO_DELAY 15
212 if (purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
&&
213 !must_be_open
&& circ
->state
!= CIRCUIT_STATE_OPEN
&&
214 circ
->timestamp_created
+ REND_PARALLEL_INTRO_DELAY
< now
) {
215 intro_going_on_but_too_old
= 1;
219 /* now this is an acceptable circ to hand back. but that doesn't
220 * mean it's the *best* circ to hand back. try to decide.
222 if (!best
|| circuit_is_better(circ
,best
,purpose
))
226 if (!best
&& intro_going_on_but_too_old
)
227 log_info(LD_REND
|LD_CIRC
, "There is an intro circuit being created "
228 "right now, but it has already taken quite a while. Starting "
231 return best
? TO_ORIGIN_CIRCUIT(best
) : NULL
;
234 /** Check whether, according to the policies in <b>options</b>, the
235 * circuit <b>circ</b> makes sense. */
236 /* XXXX currently only checks Exclude{Exit}Nodes. It should check more. */
238 circuit_conforms_to_options(const origin_circuit_t
*circ
,
239 const or_options_t
*options
)
241 const crypt_path_t
*cpath
, *cpath_next
= NULL
;
243 for (cpath
= circ
->cpath
; cpath
&& cpath_next
!= circ
->cpath
;
244 cpath
= cpath_next
) {
245 cpath_next
= cpath
->next
;
247 if (routerset_contains_extendinfo(options
->ExcludeNodes
,
251 if (cpath
->next
== circ
->cpath
) {
252 /* This is apparently the exit node. */
254 if (routerset_contains_extendinfo(options
->ExcludeExitNodes
,
262 /** Close all circuits that start at us, aren't open, and were born
263 * at least CircuitBuildTimeout seconds ago.
266 circuit_expire_building(time_t now
)
268 circuit_t
*victim
, *next_circ
= global_circuitlist
;
269 /* circ_times.timeout is BUILD_TIMEOUT_INITIAL_VALUE if we haven't
270 * decided on a customized one yet */
271 time_t general_cutoff
= now
- lround(circ_times
.timeout_ms
/1000);
272 time_t begindir_cutoff
= now
- lround(circ_times
.timeout_ms
/2000);
273 time_t close_cutoff
= now
- lround(circ_times
.close_ms
/1000);
274 time_t introcirc_cutoff
= begindir_cutoff
;
275 cpath_build_state_t
*build_state
;
280 next_circ
= next_circ
->next
;
281 if (!CIRCUIT_IS_ORIGIN(victim
) || /* didn't originate here */
282 victim
->marked_for_close
) /* don't mess with marked circs */
285 build_state
= TO_ORIGIN_CIRCUIT(victim
)->build_state
;
286 if (build_state
&& build_state
->onehop_tunnel
)
287 cutoff
= begindir_cutoff
;
288 else if (victim
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
)
289 cutoff
= introcirc_cutoff
;
290 else if (victim
->purpose
== CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
)
291 cutoff
= close_cutoff
;
293 cutoff
= general_cutoff
;
295 if (victim
->timestamp_created
> cutoff
)
296 continue; /* it's still young, leave it alone */
299 /* some debug logs, to help track bugs */
300 if (victim
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
&&
301 victim
->timestamp_created
<= introcirc_cutoff
&&
302 victim
->timestamp_created
> general_cutoff
)
303 log_info(LD_REND
|LD_CIRC
, "Timing out introduction circuit which we "
304 "would not have done if it had been a general circuit.");
306 if (victim
->purpose
>= CIRCUIT_PURPOSE_C_INTRODUCING
&&
307 victim
->purpose
<= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
) {
308 if (!victim
->timestamp_dirty
)
309 log_fn(LOG_DEBUG
,"Considering %sopen purpose %d to %s (circid %d)."
311 victim
->state
== CIRCUIT_STATE_OPEN
? "" : "non",
312 victim
->purpose
, victim
->build_state
->chosen_exit_name
,
315 log_fn(LOG_DEBUG
,"Considering %sopen purpose %d to %s (circid %d). "
316 "%d secs since dirty.",
317 victim
->state
== CIRCUIT_STATE_OPEN
? "" : "non",
318 victim
->purpose
, victim
->build_state
->chosen_exit_name
,
320 (int)(now
- victim
->timestamp_dirty
));
324 /* if circ is !open, or if it's open but purpose is a non-finished
325 * intro or rend, then mark it for close */
326 if (victim
->state
== CIRCUIT_STATE_OPEN
) {
327 switch (victim
->purpose
) {
328 default: /* most open circuits can be left alone. */
329 continue; /* yes, continue inside a switch refers to the nearest
330 * enclosing loop. C is smart. */
331 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
332 case CIRCUIT_PURPOSE_C_INTRODUCING
:
333 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
334 break; /* too old, need to die */
335 case CIRCUIT_PURPOSE_C_REND_READY
:
336 /* it's a rend_ready circ -- has it already picked a query? */
337 /* c_rend_ready circs measure age since timestamp_dirty,
338 * because that's set when they switch purposes
340 if (TO_ORIGIN_CIRCUIT(victim
)->rend_data
||
341 victim
->timestamp_dirty
> cutoff
)
344 case CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
:
345 case CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
:
346 /* rend and intro circs become dirty each time they
347 * make an introduction attempt. so timestamp_dirty
348 * will reflect the time since the last attempt.
350 if (victim
->timestamp_dirty
> cutoff
)
354 } else { /* circuit not open, consider recording failure as timeout */
355 int first_hop_succeeded
= TO_ORIGIN_CIRCUIT(victim
)->cpath
&&
356 TO_ORIGIN_CIRCUIT(victim
)->cpath
->state
== CPATH_STATE_OPEN
;
358 if (TO_ORIGIN_CIRCUIT(victim
)->p_streams
!= NULL
) {
359 log_warn(LD_BUG
, "Circuit %d (purpose %d) has timed out, "
360 "yet has attached streams!",
361 TO_ORIGIN_CIRCUIT(victim
)->global_identifier
,
363 tor_fragile_assert();
367 /* circuits are allowed to last longer for measurement.
368 * Switch their purpose and wait. */
369 if (victim
->purpose
!= CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
) {
370 victim
->purpose
= CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
;
371 circuit_build_times_count_timeout(&circ_times
,
372 first_hop_succeeded
);
377 * If the circuit build time is much greater than we would have cut
378 * it off at, we probably had a suspend event along this codepath,
379 * and we should discard the value.
381 if (now
- victim
->timestamp_created
> 2*circ_times
.close_ms
/1000+1) {
383 "Extremely large value for circuit build timeout: %lds. "
384 "Assuming clock jump.",
385 (long)(now
- victim
->timestamp_created
));
386 } else if (circuit_build_times_count_close(&circ_times
,
388 victim
->timestamp_created
)) {
389 circuit_build_times_set_timeout(&circ_times
);
394 log_info(LD_CIRC
,"Abandoning circ %s:%d:%d (state %d:%s, purpose %d)",
395 victim
->n_conn
->_base
.address
, victim
->n_conn
->_base
.port
,
397 victim
->state
, circuit_state_to_string(victim
->state
),
400 log_info(LD_CIRC
,"Abandoning circ %d (state %d:%s, purpose %d)",
401 victim
->n_circ_id
, victim
->state
,
402 circuit_state_to_string(victim
->state
), victim
->purpose
);
404 circuit_log_path(LOG_INFO
,LD_CIRC
,TO_ORIGIN_CIRCUIT(victim
));
405 circuit_mark_for_close(victim
, END_CIRC_REASON_TIMEOUT
);
409 /** Remove any elements in <b>needed_ports</b> that are handled by an
410 * open or in-progress circuit.
413 circuit_remove_handled_ports(smartlist_t
*needed_ports
)
418 for (i
= 0; i
< smartlist_len(needed_ports
); ++i
) {
419 port
= smartlist_get(needed_ports
, i
);
421 if (circuit_stream_is_being_handled(NULL
, *port
,
422 MIN_CIRCUITS_HANDLING_STREAM
)) {
423 // log_debug(LD_CIRC,"Port %d is already being handled; removing.", port);
424 smartlist_del(needed_ports
, i
--);
427 log_debug(LD_CIRC
,"Port %d is not handled.", *port
);
432 /** Return 1 if at least <b>min</b> general-purpose non-internal circuits
433 * will have an acceptable exit node for exit stream <b>conn</b> if it
434 * is defined, else for "*:port".
438 circuit_stream_is_being_handled(edge_connection_t
*conn
,
439 uint16_t port
, int min
)
442 routerinfo_t
*exitrouter
;
444 time_t now
= time(NULL
);
445 int need_uptime
= smartlist_string_num_isin(get_options()->LongLivedPorts
,
446 conn
? conn
->socks_request
->port
: port
);
448 for (circ
=global_circuitlist
;circ
;circ
= circ
->next
) {
449 if (CIRCUIT_IS_ORIGIN(circ
) &&
450 !circ
->marked_for_close
&&
451 circ
->purpose
== CIRCUIT_PURPOSE_C_GENERAL
&&
452 (!circ
->timestamp_dirty
||
453 circ
->timestamp_dirty
+ get_options()->MaxCircuitDirtiness
> now
)) {
454 cpath_build_state_t
*build_state
= TO_ORIGIN_CIRCUIT(circ
)->build_state
;
455 if (build_state
->is_internal
|| build_state
->onehop_tunnel
)
458 exitrouter
= build_state_get_exit_router(build_state
);
459 if (exitrouter
&& (!need_uptime
|| build_state
->need_uptime
)) {
462 ok
= connection_ap_can_use_exit(conn
, exitrouter
, 0);
464 addr_policy_result_t r
= compare_addr_to_addr_policy(
465 0, port
, exitrouter
->exit_policy
);
466 ok
= r
!= ADDR_POLICY_REJECTED
&& r
!= ADDR_POLICY_PROBABLY_REJECTED
;
478 /** Don't keep more than this many unused open circuits around. */
479 #define MAX_UNUSED_OPEN_CIRCUITS 14
481 /** Figure out how many circuits we have open that are clean. Make
482 * sure it's enough for all the upcoming behaviors we predict we'll have.
483 * But put an upper bound on the total number of circuits.
486 circuit_predict_and_launch_new(void)
489 int num
=0, num_internal
=0, num_uptime_internal
=0;
490 int hidserv_needs_uptime
=0, hidserv_needs_capacity
=1;
491 int port_needs_uptime
=0, port_needs_capacity
=1;
492 time_t now
= time(NULL
);
495 /* First, count how many of each type of circuit we have already. */
496 for (circ
=global_circuitlist
;circ
;circ
= circ
->next
) {
497 cpath_build_state_t
*build_state
;
498 if (!CIRCUIT_IS_ORIGIN(circ
))
500 if (circ
->marked_for_close
)
501 continue; /* don't mess with marked circs */
502 if (circ
->timestamp_dirty
)
503 continue; /* only count clean circs */
504 if (circ
->purpose
!= CIRCUIT_PURPOSE_C_GENERAL
)
505 continue; /* only pay attention to general-purpose circs */
506 build_state
= TO_ORIGIN_CIRCUIT(circ
)->build_state
;
507 if (build_state
->onehop_tunnel
)
510 if (build_state
->is_internal
)
512 if (build_state
->need_uptime
&& build_state
->is_internal
)
513 num_uptime_internal
++;
516 /* If that's enough, then stop now. */
517 if (num
>= MAX_UNUSED_OPEN_CIRCUITS
)
518 return; /* we already have many, making more probably will hurt */
520 /* Second, see if we need any more exit circuits. */
521 /* check if we know of a port that's been requested recently
522 * and no circuit is currently available that can handle it. */
523 if (!circuit_all_predicted_ports_handled(now
, &port_needs_uptime
,
524 &port_needs_capacity
)) {
525 if (port_needs_uptime
)
526 flags
|= CIRCLAUNCH_NEED_UPTIME
;
527 if (port_needs_capacity
)
528 flags
|= CIRCLAUNCH_NEED_CAPACITY
;
530 "Have %d clean circs (%d internal), need another exit circ.",
532 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
536 /* Third, see if we need any more hidden service (server) circuits. */
537 if (num_rend_services() && num_uptime_internal
< 3) {
538 flags
= (CIRCLAUNCH_NEED_CAPACITY
| CIRCLAUNCH_NEED_UPTIME
|
539 CIRCLAUNCH_IS_INTERNAL
);
541 "Have %d clean circs (%d internal), need another internal "
542 "circ for my hidden service.",
544 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
548 /* Fourth, see if we need any more hidden service (client) circuits. */
549 if (rep_hist_get_predicted_internal(now
, &hidserv_needs_uptime
,
550 &hidserv_needs_capacity
) &&
551 ((num_uptime_internal
<2 && hidserv_needs_uptime
) ||
553 if (hidserv_needs_uptime
)
554 flags
|= CIRCLAUNCH_NEED_UPTIME
;
555 if (hidserv_needs_capacity
)
556 flags
|= CIRCLAUNCH_NEED_CAPACITY
;
557 flags
|= CIRCLAUNCH_IS_INTERNAL
;
559 "Have %d clean circs (%d uptime-internal, %d internal), need"
560 " another hidden service circ.",
561 num
, num_uptime_internal
, num_internal
);
562 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
566 /* Finally, check to see if we still need more circuits to learn
567 * a good build timeout. But if we're close to our max number we
568 * want, don't do another -- we want to leave a few slots open so
569 * we can still build circuits preemptively as needed. */
570 if (num
< MAX_UNUSED_OPEN_CIRCUITS
-2 &&
571 circuit_build_times_needs_circuits_now(&circ_times
)) {
572 flags
= CIRCLAUNCH_NEED_CAPACITY
;
574 "Have %d clean circs need another buildtime test circ.", num
);
575 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
580 /** Build a new test circuit every 5 minutes */
581 #define TESTING_CIRCUIT_INTERVAL 300
583 /** This function is called once a second, if router_have_min_dir_info() is
584 * true. Its job is to make sure all services we offer have enough circuits
585 * available. Some services just want enough circuits for current tasks,
586 * whereas others want a minimum set of idle circuits hanging around.
589 circuit_build_needed_circs(time_t now
)
591 static time_t time_to_new_circuit
= 0;
592 or_options_t
*options
= get_options();
594 /* launch a new circ for any pending streams that need one */
595 connection_ap_attach_pending();
597 /* make sure any hidden services have enough intro points */
598 rend_services_introduce();
600 if (time_to_new_circuit
< now
) {
601 circuit_reset_failure_count(1);
602 time_to_new_circuit
= now
+ options
->NewCircuitPeriod
;
603 if (proxy_mode(get_options()))
604 addressmap_clean(now
);
605 circuit_expire_old_circuits_clientside(now
);
607 #if 0 /* disable for now, until predict-and-launch-new can cull leftovers */
608 circ
= circuit_get_youngest_clean_open(CIRCUIT_PURPOSE_C_GENERAL
);
609 if (get_options()->RunTesting
&&
611 circ
->timestamp_created
+ TESTING_CIRCUIT_INTERVAL
< now
) {
612 log_fn(LOG_INFO
,"Creating a new testing circuit.");
613 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, 0);
617 if (!options
->DisablePredictedCircuits
)
618 circuit_predict_and_launch_new();
621 /** If the stream <b>conn</b> is a member of any of the linked
622 * lists of <b>circ</b>, then remove it from the list.
625 circuit_detach_stream(circuit_t
*circ
, edge_connection_t
*conn
)
627 edge_connection_t
*prevconn
;
632 conn
->cpath_layer
= NULL
; /* make sure we don't keep a stale pointer */
633 conn
->on_circuit
= NULL
;
635 if (CIRCUIT_IS_ORIGIN(circ
)) {
636 origin_circuit_t
*origin_circ
= TO_ORIGIN_CIRCUIT(circ
);
637 if (conn
== origin_circ
->p_streams
) {
638 origin_circ
->p_streams
= conn
->next_stream
;
642 for (prevconn
= origin_circ
->p_streams
;
643 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
644 prevconn
= prevconn
->next_stream
)
646 if (prevconn
&& prevconn
->next_stream
) {
647 prevconn
->next_stream
= conn
->next_stream
;
651 or_circuit_t
*or_circ
= TO_OR_CIRCUIT(circ
);
652 if (conn
== or_circ
->n_streams
) {
653 or_circ
->n_streams
= conn
->next_stream
;
656 if (conn
== or_circ
->resolving_streams
) {
657 or_circ
->resolving_streams
= conn
->next_stream
;
661 for (prevconn
= or_circ
->n_streams
;
662 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
663 prevconn
= prevconn
->next_stream
)
665 if (prevconn
&& prevconn
->next_stream
) {
666 prevconn
->next_stream
= conn
->next_stream
;
670 for (prevconn
= or_circ
->resolving_streams
;
671 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
672 prevconn
= prevconn
->next_stream
)
674 if (prevconn
&& prevconn
->next_stream
) {
675 prevconn
->next_stream
= conn
->next_stream
;
680 log_warn(LD_BUG
,"Edge connection not in circuit's list.");
681 /* Don't give an error here; it's harmless. */
682 tor_fragile_assert();
685 /** If we haven't yet decided on a good timeout value for circuit
686 * building, we close idles circuits aggressively so we can get more
688 #define IDLE_TIMEOUT_WHILE_LEARNING (10*60)
690 /** Find each circuit that has been unused for too long, or dirty
691 * for too long and has no streams on it: mark it for close.
694 circuit_expire_old_circuits_clientside(time_t now
)
699 if (circuit_build_times_needs_circuits(&circ_times
)) {
700 /* Circuits should be shorter lived if we need more of them
701 * for learning a good build timeout */
702 cutoff
= now
- IDLE_TIMEOUT_WHILE_LEARNING
;
704 cutoff
= now
- get_options()->CircuitIdleTimeout
;
707 for (circ
= global_circuitlist
; circ
; circ
= circ
->next
) {
708 if (circ
->marked_for_close
|| ! CIRCUIT_IS_ORIGIN(circ
))
710 /* If the circuit has been dirty for too long, and there are no streams
711 * on it, mark it for close.
713 if (circ
->timestamp_dirty
&&
714 circ
->timestamp_dirty
+ get_options()->MaxCircuitDirtiness
< now
&&
715 !TO_ORIGIN_CIRCUIT(circ
)->p_streams
/* nothing attached */ ) {
716 log_debug(LD_CIRC
, "Closing n_circ_id %d (dirty %d secs ago, "
718 circ
->n_circ_id
, (int)(now
- circ
->timestamp_dirty
),
720 circuit_mark_for_close(circ
, END_CIRC_REASON_FINISHED
);
721 } else if (!circ
->timestamp_dirty
&& circ
->state
== CIRCUIT_STATE_OPEN
) {
722 if (circ
->timestamp_created
< cutoff
) {
723 if (circ
->purpose
== CIRCUIT_PURPOSE_C_GENERAL
||
724 circ
->purpose
== CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
||
725 circ
->purpose
== CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
||
726 circ
->purpose
== CIRCUIT_PURPOSE_TESTING
||
727 (circ
->purpose
>= CIRCUIT_PURPOSE_C_INTRODUCING
&&
728 circ
->purpose
<= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
) ||
729 circ
->purpose
== CIRCUIT_PURPOSE_S_CONNECT_REND
) {
731 "Closing circuit that has been unused for %ld seconds.",
732 (long)(now
- circ
->timestamp_created
));
733 circuit_mark_for_close(circ
, END_CIRC_REASON_FINISHED
);
734 } else if (!TO_ORIGIN_CIRCUIT(circ
)->is_ancient
) {
736 "Ancient non-dirty circuit %d is still around after "
737 "%ld seconds. Purpose: %d",
738 TO_ORIGIN_CIRCUIT(circ
)->global_identifier
,
739 (long)(now
- circ
->timestamp_created
),
741 TO_ORIGIN_CIRCUIT(circ
)->is_ancient
= 1;
748 /** How long do we wait before killing circuits with the properties
751 * Probably we could choose a number here as low as 5 to 10 seconds,
752 * since these circs are used for begindir, and a) generally you either
753 * ask another begindir question right after or you don't for a long time,
754 * b) clients at least through 0.2.1.x choose from the whole set of
755 * directory mirrors at each choice, and c) re-establishing a one-hop
756 * circuit via create-fast is a light operation assuming the TLS conn is
759 * I expect "b" to go away one day when we move to using directory
760 * guards, but I think "a" and "c" are good enough reasons that a low
761 * number is safe even then.
763 #define IDLE_ONE_HOP_CIRC_TIMEOUT 60
765 /** Find each non-origin circuit that has been unused for too long,
766 * has no streams on it, used a create_fast, and ends here: mark it
770 circuit_expire_old_circuits_serverside(time_t now
)
773 or_circuit_t
*or_circ
;
774 time_t cutoff
= now
- IDLE_ONE_HOP_CIRC_TIMEOUT
;
776 for (circ
= global_circuitlist
; circ
; circ
= circ
->next
) {
777 if (circ
->marked_for_close
|| CIRCUIT_IS_ORIGIN(circ
))
779 or_circ
= TO_OR_CIRCUIT(circ
);
780 /* If the circuit has been idle for too long, and there are no streams
781 * on it, and it ends here, and it used a create_fast, mark it for close.
783 if (or_circ
->is_first_hop
&& !circ
->n_conn
&&
784 !or_circ
->n_streams
&& !or_circ
->resolving_streams
&&
786 or_circ
->p_conn
->timestamp_last_added_nonpadding
<= cutoff
) {
787 log_info(LD_CIRC
, "Closing circ_id %d (empty %d secs ago)",
789 (int)(now
- or_circ
->p_conn
->timestamp_last_added_nonpadding
));
790 circuit_mark_for_close(circ
, END_CIRC_REASON_FINISHED
);
795 /** Number of testing circuits we want open before testing our bandwidth. */
796 #define NUM_PARALLEL_TESTING_CIRCS 4
798 /** True iff we've ever had enough testing circuits open to test our
800 static int have_performed_bandwidth_test
= 0;
802 /** Reset have_performed_bandwidth_test, so we'll start building
803 * testing circuits again so we can exercise our bandwidth. */
805 reset_bandwidth_test(void)
807 have_performed_bandwidth_test
= 0;
810 /** Return 1 if we've already exercised our bandwidth, or if we
811 * have fewer than NUM_PARALLEL_TESTING_CIRCS testing circuits
812 * established or on the way. Else return 0.
815 circuit_enough_testing_circs(void)
820 if (have_performed_bandwidth_test
)
823 for (circ
= global_circuitlist
; circ
; circ
= circ
->next
) {
824 if (!circ
->marked_for_close
&& CIRCUIT_IS_ORIGIN(circ
) &&
825 circ
->purpose
== CIRCUIT_PURPOSE_TESTING
&&
826 circ
->state
== CIRCUIT_STATE_OPEN
)
829 return num
>= NUM_PARALLEL_TESTING_CIRCS
;
832 /** A testing circuit has completed. Take whatever stats we want.
833 * Noticing reachability is taken care of in onionskin_answer(),
834 * so there's no need to record anything here. But if we still want
835 * to do the bandwidth test, and we now have enough testing circuits
839 circuit_testing_opened(origin_circuit_t
*circ
)
841 if (have_performed_bandwidth_test
||
842 !check_whether_orport_reachable()) {
843 /* either we've already done everything we want with testing circuits,
844 * or this testing circuit became open due to a fluke, e.g. we picked
845 * a last hop where we already had the connection open due to an
846 * outgoing local circuit. */
847 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_AT_ORIGIN
);
848 } else if (circuit_enough_testing_circs()) {
849 router_perform_bandwidth_test(NUM_PARALLEL_TESTING_CIRCS
, time(NULL
));
850 have_performed_bandwidth_test
= 1;
852 consider_testing_reachability(1, 0);
855 /** A testing circuit has failed to build. Take whatever stats we want. */
857 circuit_testing_failed(origin_circuit_t
*circ
, int at_last_hop
)
859 if (server_mode(get_options()) && check_whether_orport_reachable())
863 "Our testing circuit (to see if your ORPort is reachable) "
864 "has failed. I'll try again later.");
866 /* These aren't used yet. */
871 /** The circuit <b>circ</b> has just become open. Take the next
872 * step: for rendezvous circuits, we pass circ to the appropriate
873 * function in rendclient or rendservice. For general circuits, we
874 * call connection_ap_attach_pending, which looks for pending streams
875 * that could use circ.
878 circuit_has_opened(origin_circuit_t
*circ
)
880 control_event_circuit_status(circ
, CIRC_EVENT_BUILT
, 0);
882 switch (TO_CIRCUIT(circ
)->purpose
) {
883 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
884 rend_client_rendcirc_has_opened(circ
);
885 connection_ap_attach_pending();
887 case CIRCUIT_PURPOSE_C_INTRODUCING
:
888 rend_client_introcirc_has_opened(circ
);
890 case CIRCUIT_PURPOSE_C_GENERAL
:
891 /* Tell any AP connections that have been waiting for a new
892 * circuit that one is ready. */
893 connection_ap_attach_pending();
895 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
896 /* at Bob, waiting for introductions */
897 rend_service_intro_has_opened(circ
);
899 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
900 /* at Bob, connecting to rend point */
901 rend_service_rendezvous_has_opened(circ
);
903 case CIRCUIT_PURPOSE_TESTING
:
904 circuit_testing_opened(circ
);
907 * This won't happen in normal operation, but might happen if the
908 * controller did it. Just let it slide. */
912 /** Called whenever a circuit could not be successfully built.
915 circuit_build_failed(origin_circuit_t
*circ
)
917 /* we should examine circ and see if it failed because of
918 * the last hop or an earlier hop. then use this info below.
920 int failed_at_last_hop
= 0;
921 /* If the last hop isn't open, and the second-to-last is, we failed
922 * at the last hop. */
924 circ
->cpath
->prev
->state
!= CPATH_STATE_OPEN
&&
925 circ
->cpath
->prev
->prev
->state
== CPATH_STATE_OPEN
) {
926 failed_at_last_hop
= 1;
929 circ
->cpath
->state
!= CPATH_STATE_OPEN
) {
930 /* We failed at the first hop. If there's an OR connection
931 * to blame, blame it. Also, avoid this relay for a while, and
932 * fail any one-hop directory fetches destined for it. */
933 const char *n_conn_id
= circ
->cpath
->extend_info
->identity_digest
;
934 if (circ
->_base
.n_conn
) {
935 or_connection_t
*n_conn
= circ
->_base
.n_conn
;
937 "Our circuit failed to get a response from the first hop "
938 "(%s:%d). I'm going to try to rotate to a better connection.",
939 n_conn
->_base
.address
, n_conn
->_base
.port
);
940 n_conn
->is_bad_for_new_circs
= 1;
943 "Our circuit died before the first hop with no connection");
946 entry_guard_register_connect_status(n_conn_id
, 0, 1, time(NULL
));
947 /* if there are any one-hop streams waiting on this circuit, fail
948 * them now so they can retry elsewhere. */
949 connection_ap_fail_onehop(n_conn_id
, circ
->build_state
);
953 switch (circ
->_base
.purpose
) {
954 case CIRCUIT_PURPOSE_C_GENERAL
:
955 /* If we never built the circuit, note it as a failure. */
956 circuit_increment_failure_count();
957 if (failed_at_last_hop
) {
958 /* Make sure any streams that demand our last hop as their exit
959 * know that it's unlikely to happen. */
960 circuit_discard_optional_exit_enclaves(circ
->cpath
->prev
->extend_info
);
963 case CIRCUIT_PURPOSE_TESTING
:
964 circuit_testing_failed(circ
, failed_at_last_hop
);
966 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
967 /* at Bob, waiting for introductions */
968 if (circ
->_base
.state
!= CIRCUIT_STATE_OPEN
) {
969 circuit_increment_failure_count();
971 /* no need to care here, because bob will rebuild intro
972 * points periodically. */
974 case CIRCUIT_PURPOSE_C_INTRODUCING
:
975 /* at Alice, connecting to intro point */
976 /* Don't increment failure count, since Bob may have picked
977 * the introduction point maliciously */
978 /* Alice will pick a new intro point when this one dies, if
979 * the stream in question still cares. No need to act here. */
981 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
982 /* at Alice, waiting for Bob */
983 circuit_increment_failure_count();
984 /* Alice will pick a new rend point when this one dies, if
985 * the stream in question still cares. No need to act here. */
987 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
988 /* at Bob, connecting to rend point */
989 /* Don't increment failure count, since Alice may have picked
990 * the rendezvous point maliciously */
992 "Couldn't connect to Alice's chosen rend point %s "
994 escaped(build_state_get_exit_nickname(circ
->build_state
)),
995 failed_at_last_hop
?"last":"non-last");
996 rend_service_relaunch_rendezvous(circ
);
999 * This won't happen in normal operation, but might happen if the
1000 * controller did it. Just let it slide. */
1004 /** Number of consecutive failures so far; should only be touched by
1005 * circuit_launch_new and circuit_*_failure_count.
1007 static int n_circuit_failures
= 0;
1008 /** Before the last time we called circuit_reset_failure_count(), were
1009 * there a lot of failures? */
1010 static int did_circs_fail_last_period
= 0;
1012 /** Don't retry launching a new circuit if we try this many times with no
1014 #define MAX_CIRCUIT_FAILURES 5
1016 /** Launch a new circuit; see circuit_launch_by_extend_info() for
1017 * details on arguments. */
1019 circuit_launch_by_router(uint8_t purpose
,
1020 routerinfo_t
*exit
, int flags
)
1022 origin_circuit_t
*circ
;
1023 extend_info_t
*info
= NULL
;
1025 info
= extend_info_from_router(exit
);
1026 circ
= circuit_launch_by_extend_info(purpose
, info
, flags
);
1028 extend_info_free(info
);
1032 /** Launch a new circuit with purpose <b>purpose</b> and exit node
1033 * <b>extend_info</b> (or NULL to select a random exit node). If flags
1034 * contains CIRCLAUNCH_NEED_UPTIME, choose among routers with high uptime. If
1035 * CIRCLAUNCH_NEED_CAPACITY is set, choose among routers with high bandwidth.
1036 * If CIRCLAUNCH_IS_INTERNAL is true, the last hop need not be an exit node.
1037 * If CIRCLAUNCH_ONEHOP_TUNNEL is set, the circuit will have only one hop.
1038 * Return the newly allocated circuit on success, or NULL on failure. */
1040 circuit_launch_by_extend_info(uint8_t purpose
,
1041 extend_info_t
*extend_info
,
1044 origin_circuit_t
*circ
;
1045 int onehop_tunnel
= (flags
& CIRCLAUNCH_ONEHOP_TUNNEL
) != 0;
1047 if (!onehop_tunnel
&& !router_have_minimum_dir_info()) {
1048 log_debug(LD_CIRC
,"Haven't fetched enough directory info yet; canceling "
1053 if ((extend_info
|| purpose
!= CIRCUIT_PURPOSE_C_GENERAL
) &&
1054 purpose
!= CIRCUIT_PURPOSE_TESTING
&& !onehop_tunnel
) {
1055 /* see if there are appropriate circs available to cannibalize. */
1056 /* XXX if we're planning to add a hop, perhaps we want to look for
1057 * internal circs rather than exit circs? -RD */
1058 circ
= circuit_find_to_cannibalize(purpose
, extend_info
, flags
);
1060 log_info(LD_CIRC
,"Cannibalizing circ '%s' for purpose %d",
1061 build_state_get_exit_nickname(circ
->build_state
), purpose
);
1062 circ
->_base
.purpose
= purpose
;
1063 /* reset the birth date of this circ, else expire_building
1064 * will see it and think it's been trying to build since it
1066 circ
->_base
.timestamp_created
= time(NULL
);
1068 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
1069 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
1070 /* it's ready right now */
1072 case CIRCUIT_PURPOSE_C_INTRODUCING
:
1073 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
1074 case CIRCUIT_PURPOSE_C_GENERAL
:
1075 /* need to add a new hop */
1076 tor_assert(extend_info
);
1077 if (circuit_extend_to_new_exit(circ
, extend_info
) < 0)
1082 "unexpected purpose %d when cannibalizing a circ.",
1084 tor_fragile_assert();
1091 if (did_circs_fail_last_period
&&
1092 n_circuit_failures
> MAX_CIRCUIT_FAILURES
) {
1093 /* too many failed circs in a row. don't try. */
1094 // log_fn(LOG_INFO,"%d failures so far, not trying.",n_circuit_failures);
1098 /* try a circ. if it fails, circuit_mark_for_close will increment
1099 * n_circuit_failures */
1100 return circuit_establish_circuit(purpose
, extend_info
, flags
);
1103 /** Record another failure at opening a general circuit. When we have
1104 * too many, we'll stop trying for the remainder of this minute.
1107 circuit_increment_failure_count(void)
1109 ++n_circuit_failures
;
1110 log_debug(LD_CIRC
,"n_circuit_failures now %d.",n_circuit_failures
);
1113 /** Reset the failure count for opening general circuits. This means
1114 * we will try MAX_CIRCUIT_FAILURES times more (if necessary) before
1118 circuit_reset_failure_count(int timeout
)
1120 if (timeout
&& n_circuit_failures
> MAX_CIRCUIT_FAILURES
)
1121 did_circs_fail_last_period
= 1;
1123 did_circs_fail_last_period
= 0;
1124 n_circuit_failures
= 0;
1127 /** Find an open circ that we're happy to use for <b>conn</b> and return 1. If
1128 * there isn't one, and there isn't one on the way, launch one and return
1129 * 0. If it will never work, return -1.
1131 * Write the found or in-progress or launched circ into *circp.
1134 circuit_get_open_circ_or_launch(edge_connection_t
*conn
,
1135 uint8_t desired_circuit_purpose
,
1136 origin_circuit_t
**circp
)
1138 origin_circuit_t
*circ
;
1139 int check_exit_policy
;
1140 int need_uptime
, need_internal
;
1142 or_options_t
*options
= get_options();
1146 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
);
1148 conn
->socks_request
->command
== SOCKS_COMMAND_CONNECT
&&
1149 !conn
->use_begindir
&&
1150 !connection_edge_is_rendezvous_stream(conn
);
1151 want_onehop
= conn
->want_onehop
;
1153 need_uptime
= !conn
->want_onehop
&& !conn
->use_begindir
&&
1154 smartlist_string_num_isin(options
->LongLivedPorts
,
1155 conn
->socks_request
->port
);
1156 need_internal
= desired_circuit_purpose
!= CIRCUIT_PURPOSE_C_GENERAL
;
1158 circ
= circuit_get_best(conn
, 1, desired_circuit_purpose
,
1159 need_uptime
, need_internal
);
1163 return 1; /* we're happy */
1166 if (!want_onehop
&& !router_have_minimum_dir_info()) {
1167 if (!connection_get_by_type(CONN_TYPE_DIR
)) {
1168 int severity
= LOG_NOTICE
;
1169 /* FFFF if this is a tunneled directory fetch, don't yell
1170 * as loudly. the user doesn't even know it's happening. */
1171 if (options
->UseBridges
&& bridges_known_but_down()) {
1172 log_fn(severity
, LD_APP
|LD_DIR
,
1173 "Application request when we're believed to be "
1174 "offline. Optimistically trying known bridges again.");
1175 bridges_retry_all();
1176 } else if (!options
->UseBridges
|| any_bridge_descriptors_known()) {
1177 log_fn(severity
, LD_APP
|LD_DIR
,
1178 "Application request when we're believed to be "
1179 "offline. Optimistically trying directory fetches again.");
1180 routerlist_retry_directory_downloads(time(NULL
));
1183 /* the stream will be dealt with when router_have_minimum_dir_info becomes
1184 * 1, or when all directory attempts fail and directory_all_unreachable()
1190 /* Do we need to check exit policy? */
1191 if (check_exit_policy
) {
1192 if (!conn
->chosen_exit_name
) {
1195 if (tor_inet_aton(conn
->socks_request
->address
, &in
))
1196 addr
= ntohl(in
.s_addr
);
1197 if (router_exit_policy_all_routers_reject(addr
,
1198 conn
->socks_request
->port
,
1201 "No Tor server allows exit to %s:%d. Rejecting.",
1202 safe_str_client(conn
->socks_request
->address
),
1203 conn
->socks_request
->port
);
1207 /* XXXX022 Duplicates checks in connection_ap_handshake_attach_circuit */
1208 routerinfo_t
*router
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1209 int opt
= conn
->chosen_exit_optional
;
1210 if (router
&& !connection_ap_can_use_exit(conn
, router
, 0)) {
1211 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1212 "Requested exit point '%s' would refuse request. %s.",
1213 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1215 conn
->chosen_exit_optional
= 0;
1216 tor_free(conn
->chosen_exit_name
);
1218 return circuit_get_open_circ_or_launch(conn
,
1219 desired_circuit_purpose
,
1227 /* is one already on the way? */
1228 circ
= circuit_get_best(conn
, 0, desired_circuit_purpose
,
1229 need_uptime
, need_internal
);
1231 log_debug(LD_CIRC
, "one on the way!");
1233 extend_info_t
*extend_info
=NULL
;
1234 uint8_t new_circ_purpose
;
1236 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
) {
1237 /* need to pick an intro point */
1238 tor_assert(conn
->rend_data
);
1239 extend_info
= rend_client_get_random_intro(conn
->rend_data
);
1242 "No intro points for '%s': re-fetching service descriptor.",
1243 safe_str_client(conn
->rend_data
->onion_address
));
1244 rend_client_refetch_v2_renddesc(conn
->rend_data
);
1245 conn
->_base
.state
= AP_CONN_STATE_RENDDESC_WAIT
;
1248 log_info(LD_REND
,"Chose '%s' as intro point for '%s'.",
1249 extend_info
->nickname
,
1250 safe_str_client(conn
->rend_data
->onion_address
));
1253 /* If we have specified a particular exit node for our
1254 * connection, then be sure to open a circuit to that exit node.
1256 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_GENERAL
) {
1257 if (conn
->chosen_exit_name
) {
1259 int opt
= conn
->chosen_exit_optional
;
1260 r
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1262 extend_info
= extend_info_from_router(r
);
1264 log_debug(LD_DIR
, "considering %d, %s",
1265 want_onehop
, conn
->chosen_exit_name
);
1266 if (want_onehop
&& conn
->chosen_exit_name
[0] == '$') {
1267 /* We're asking for a one-hop circuit to a router that
1268 * we don't have a routerinfo about. Make up an extend_info. */
1269 char digest
[DIGEST_LEN
];
1270 char *hexdigest
= conn
->chosen_exit_name
+1;
1272 if (strlen(hexdigest
) < HEX_DIGEST_LEN
||
1273 base16_decode(digest
,DIGEST_LEN
,hexdigest
,HEX_DIGEST_LEN
)<0) {
1274 log_info(LD_DIR
, "Broken exit digest on tunnel conn. Closing.");
1277 if (tor_addr_from_str(&addr
, conn
->socks_request
->address
) < 0) {
1278 log_info(LD_DIR
, "Broken address %s on tunnel conn. Closing.",
1279 escaped_safe_str_client(conn
->socks_request
->address
));
1282 extend_info
= extend_info_alloc(conn
->chosen_exit_name
+1,
1283 digest
, NULL
, &addr
,
1284 conn
->socks_request
->port
);
1286 /* We will need an onion key for the router, and we
1287 * don't have one. Refuse or relax requirements. */
1288 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1289 "Requested exit point '%s' is not known. %s.",
1290 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1292 conn
->chosen_exit_optional
= 0;
1293 tor_free(conn
->chosen_exit_name
);
1294 /* Try again with no requested exit */
1295 return circuit_get_open_circ_or_launch(conn
,
1296 desired_circuit_purpose
,
1305 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_REND_JOINED
)
1306 new_circ_purpose
= CIRCUIT_PURPOSE_C_ESTABLISH_REND
;
1307 else if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
)
1308 new_circ_purpose
= CIRCUIT_PURPOSE_C_INTRODUCING
;
1310 new_circ_purpose
= desired_circuit_purpose
;
1313 int flags
= CIRCLAUNCH_NEED_CAPACITY
;
1314 if (want_onehop
) flags
|= CIRCLAUNCH_ONEHOP_TUNNEL
;
1315 if (need_uptime
) flags
|= CIRCLAUNCH_NEED_UPTIME
;
1316 if (need_internal
) flags
|= CIRCLAUNCH_IS_INTERNAL
;
1317 circ
= circuit_launch_by_extend_info(new_circ_purpose
, extend_info
,
1321 extend_info_free(extend_info
);
1323 if (desired_circuit_purpose
!= CIRCUIT_PURPOSE_C_GENERAL
) {
1324 /* help predict this next time */
1325 rep_hist_note_used_internal(time(NULL
), need_uptime
, 1);
1327 /* write the service_id into circ */
1328 circ
->rend_data
= rend_data_dup(conn
->rend_data
);
1329 if (circ
->_base
.purpose
== CIRCUIT_PURPOSE_C_ESTABLISH_REND
&&
1330 circ
->_base
.state
== CIRCUIT_STATE_OPEN
)
1331 rend_client_rendcirc_has_opened(circ
);
1337 "No safe circuit (purpose %d) ready for edge "
1338 "connection; delaying.",
1339 desired_circuit_purpose
);
1344 /** Return true iff <b>crypt_path</b> is one of the crypt_paths for
1347 cpath_is_on_circuit(origin_circuit_t
*circ
, crypt_path_t
*crypt_path
)
1349 crypt_path_t
*cpath
, *cpath_next
= NULL
;
1350 for (cpath
= circ
->cpath
; cpath_next
!= circ
->cpath
; cpath
= cpath_next
) {
1351 cpath_next
= cpath
->next
;
1352 if (crypt_path
== cpath
)
1358 /** Attach the AP stream <b>apconn</b> to circ's linked list of
1359 * p_streams. Also set apconn's cpath_layer to <b>cpath</b>, or to the last
1360 * hop in circ's cpath if <b>cpath</b> is NULL.
1363 link_apconn_to_circ(edge_connection_t
*apconn
, origin_circuit_t
*circ
,
1364 crypt_path_t
*cpath
)
1366 /* add it into the linked list of streams on this circuit */
1367 log_debug(LD_APP
|LD_CIRC
, "attaching new conn to circ. n_circ_id %d.",
1368 circ
->_base
.n_circ_id
);
1369 /* reset it, so we can measure circ timeouts */
1370 apconn
->_base
.timestamp_lastread
= time(NULL
);
1371 apconn
->next_stream
= circ
->p_streams
;
1372 apconn
->on_circuit
= TO_CIRCUIT(circ
);
1373 /* assert_connection_ok(conn, time(NULL)); */
1374 circ
->p_streams
= apconn
;
1376 if (cpath
) { /* we were given one; use it */
1377 tor_assert(cpath_is_on_circuit(circ
, cpath
));
1378 apconn
->cpath_layer
= cpath
;
1379 } else { /* use the last hop in the circuit */
1380 tor_assert(circ
->cpath
);
1381 tor_assert(circ
->cpath
->prev
);
1382 tor_assert(circ
->cpath
->prev
->state
== CPATH_STATE_OPEN
);
1383 apconn
->cpath_layer
= circ
->cpath
->prev
;
1387 /** If an exit wasn't specifically chosen, save the history for future
1390 consider_recording_trackhost(edge_connection_t
*conn
, origin_circuit_t
*circ
)
1392 int found_needle
= 0;
1393 or_options_t
*options
= get_options();
1396 char fp
[HEX_DIGEST_LEN
+1];
1398 /* Search the addressmap for this conn's destination. */
1399 /* If he's not in the address map.. */
1400 if (!options
->TrackHostExits
||
1401 addressmap_have_mapping(conn
->socks_request
->address
,
1402 options
->TrackHostExitsExpire
))
1403 return; /* nothing to track, or already mapped */
1405 SMARTLIST_FOREACH(options
->TrackHostExits
, const char *, cp
, {
1406 if (cp
[0] == '.') { /* match end */
1407 if (cp
[1] == '\0' ||
1408 !strcasecmpend(conn
->socks_request
->address
, cp
) ||
1409 !strcasecmp(conn
->socks_request
->address
, &cp
[1]))
1411 } else if (strcasecmp(cp
, conn
->socks_request
->address
) == 0) {
1416 if (!found_needle
|| !circ
->build_state
->chosen_exit
)
1419 /* write down the fingerprint of the chosen exit, not the nickname,
1420 * because the chosen exit might not be named. */
1421 base16_encode(fp
, sizeof(fp
),
1422 circ
->build_state
->chosen_exit
->identity_digest
, DIGEST_LEN
);
1424 /* Add this exit/hostname pair to the addressmap. */
1425 len
= strlen(conn
->socks_request
->address
) + 1 /* '.' */ +
1426 strlen(fp
) + 1 /* '.' */ +
1427 strlen("exit") + 1 /* '\0' */;
1428 new_address
= tor_malloc(len
);
1430 tor_snprintf(new_address
, len
, "%s.%s.exit",
1431 conn
->socks_request
->address
, fp
);
1433 addressmap_register(conn
->socks_request
->address
, new_address
,
1434 time(NULL
) + options
->TrackHostExitsExpire
,
1435 ADDRMAPSRC_TRACKEXIT
);
1438 /** Attempt to attach the connection <b>conn</b> to <b>circ</b>, and send a
1439 * begin or resolve cell as appropriate. Return values are as for
1440 * connection_ap_handshake_attach_circuit. The stream will exit from the hop
1441 * indicated by <b>cpath</b>, or from the last hop in circ's cpath if
1442 * <b>cpath</b> is NULL. */
1444 connection_ap_handshake_attach_chosen_circuit(edge_connection_t
*conn
,
1445 origin_circuit_t
*circ
,
1446 crypt_path_t
*cpath
)
1449 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
||
1450 conn
->_base
.state
== AP_CONN_STATE_CONTROLLER_WAIT
);
1451 tor_assert(conn
->socks_request
);
1453 tor_assert(circ
->_base
.state
== CIRCUIT_STATE_OPEN
);
1455 conn
->_base
.state
= AP_CONN_STATE_CIRCUIT_WAIT
;
1457 if (!circ
->_base
.timestamp_dirty
)
1458 circ
->_base
.timestamp_dirty
= time(NULL
);
1460 link_apconn_to_circ(conn
, circ
, cpath
);
1461 tor_assert(conn
->socks_request
);
1462 if (conn
->socks_request
->command
== SOCKS_COMMAND_CONNECT
) {
1463 if (!conn
->use_begindir
)
1464 consider_recording_trackhost(conn
, circ
);
1465 if (connection_ap_handshake_send_begin(conn
) < 0)
1468 if (connection_ap_handshake_send_resolve(conn
) < 0)
1475 /** Try to find a safe live circuit for CONN_TYPE_AP connection conn. If
1476 * we don't find one: if conn cannot be handled by any known nodes,
1477 * warn and return -1 (conn needs to die, and is maybe already marked);
1478 * else launch new circuit (if necessary) and return 0.
1479 * Otherwise, associate conn with a safe live circuit, do the
1480 * right next step, and return 1.
1482 /* XXXX this function should mark for close whenever it returns -1;
1483 * its callers shouldn't have to worry about that. */
1485 connection_ap_handshake_attach_circuit(edge_connection_t
*conn
)
1492 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
);
1493 tor_assert(conn
->socks_request
);
1494 want_onehop
= conn
->want_onehop
;
1496 conn_age
= (int)(time(NULL
) - conn
->_base
.timestamp_created
);
1498 if (conn_age
>= get_options()->SocksTimeout
) {
1499 int severity
= (tor_addr_is_null(&conn
->_base
.addr
) && !conn
->_base
.port
) ?
1500 LOG_INFO
: LOG_NOTICE
;
1501 log_fn(severity
, LD_APP
,
1502 "Tried for %d seconds to get a connection to %s:%d. Giving up.",
1503 conn_age
, safe_str_client(conn
->socks_request
->address
),
1504 conn
->socks_request
->port
);
1508 if (!connection_edge_is_rendezvous_stream(conn
)) { /* we're a general conn */
1509 origin_circuit_t
*circ
=NULL
;
1511 if (conn
->chosen_exit_name
) {
1512 routerinfo_t
*router
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1513 int opt
= conn
->chosen_exit_optional
;
1514 if (!router
&& !want_onehop
) {
1515 /* We ran into this warning when trying to extend a circuit to a
1516 * hidden service directory for which we didn't have a router
1517 * descriptor. See flyspray task 767 for more details. We should
1518 * keep this in mind when deciding to use BEGIN_DIR cells for other
1519 * directory requests as well. -KL*/
1520 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1521 "Requested exit point '%s' is not known. %s.",
1522 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1524 conn
->chosen_exit_optional
= 0;
1525 tor_free(conn
->chosen_exit_name
);
1530 if (router
&& !connection_ap_can_use_exit(conn
, router
, 0)) {
1531 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1532 "Requested exit point '%s' would refuse request. %s.",
1533 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1535 conn
->chosen_exit_optional
= 0;
1536 tor_free(conn
->chosen_exit_name
);
1543 /* find the circuit that we should use, if there is one. */
1544 retval
= circuit_get_open_circ_or_launch(
1545 conn
, CIRCUIT_PURPOSE_C_GENERAL
, &circ
);
1546 if (retval
< 1) // XXX021 if we totally fail, this still returns 0 -RD
1549 log_debug(LD_APP
|LD_CIRC
,
1550 "Attaching apconn to circ %d (stream %d sec old).",
1551 circ
->_base
.n_circ_id
, conn_age
);
1552 /* print the circ's path, so people can figure out which circs are
1554 circuit_log_path(LOG_INFO
,LD_APP
|LD_CIRC
,circ
);
1556 /* We have found a suitable circuit for our conn. Hurray. */
1557 return connection_ap_handshake_attach_chosen_circuit(conn
, circ
, NULL
);
1559 } else { /* we're a rendezvous conn */
1560 origin_circuit_t
*rendcirc
=NULL
, *introcirc
=NULL
;
1562 tor_assert(!conn
->cpath_layer
);
1564 /* start by finding a rendezvous circuit for us */
1566 retval
= circuit_get_open_circ_or_launch(
1567 conn
, CIRCUIT_PURPOSE_C_REND_JOINED
, &rendcirc
);
1568 if (retval
< 0) return -1; /* failed */
1571 tor_assert(rendcirc
);
1572 /* one is already established, attach */
1574 "rend joined circ %d already here. attaching. "
1575 "(stream %d sec old)",
1576 rendcirc
->_base
.n_circ_id
, conn_age
);
1577 /* Mark rendezvous circuits as 'newly dirty' every time you use
1578 * them, since the process of rebuilding a rendezvous circ is so
1579 * expensive. There is a tradeoff between linkability and
1580 * feasibility, at this point.
1582 rendcirc
->_base
.timestamp_dirty
= time(NULL
);
1583 link_apconn_to_circ(conn
, rendcirc
, NULL
);
1584 if (connection_ap_handshake_send_begin(conn
) < 0)
1585 return 0; /* already marked, let them fade away */
1589 if (rendcirc
&& (rendcirc
->_base
.purpose
==
1590 CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
)) {
1592 "pending-join circ %d already here, with intro ack. "
1593 "Stalling. (stream %d sec old)",
1594 rendcirc
->_base
.n_circ_id
, conn_age
);
1598 /* it's on its way. find an intro circ. */
1599 retval
= circuit_get_open_circ_or_launch(
1600 conn
, CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
, &introcirc
);
1601 if (retval
< 0) return -1; /* failed */
1604 /* one has already sent the intro. keep waiting. */
1605 circuit_t
*c
= NULL
;
1606 tor_assert(introcirc
);
1607 log_info(LD_REND
, "Intro circ %d present and awaiting ack (rend %d). "
1608 "Stalling. (stream %d sec old)",
1609 introcirc
->_base
.n_circ_id
,
1610 rendcirc
? rendcirc
->_base
.n_circ_id
: 0,
1612 /* abort parallel intro circs, if any */
1613 for (c
= global_circuitlist
; c
; c
= c
->next
) {
1614 if (c
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
&&
1615 !c
->marked_for_close
&& CIRCUIT_IS_ORIGIN(c
)) {
1616 origin_circuit_t
*oc
= TO_ORIGIN_CIRCUIT(c
);
1617 if (oc
->rend_data
&&
1618 !rend_cmp_service_ids(conn
->rend_data
->onion_address
,
1619 oc
->rend_data
->onion_address
)) {
1620 log_info(LD_REND
|LD_CIRC
, "Closing introduction circuit that we "
1621 "built in parallel.");
1622 circuit_mark_for_close(c
, END_CIRC_REASON_TIMEOUT
);
1629 /* now rendcirc and introcirc are each either undefined or not finished */
1631 if (rendcirc
&& introcirc
&&
1632 rendcirc
->_base
.purpose
== CIRCUIT_PURPOSE_C_REND_READY
) {
1634 "ready rend circ %d already here (no intro-ack yet on "
1635 "intro %d). (stream %d sec old)",
1636 rendcirc
->_base
.n_circ_id
,
1637 introcirc
->_base
.n_circ_id
, conn_age
);
1639 tor_assert(introcirc
->_base
.purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
);
1640 if (introcirc
->_base
.state
== CIRCUIT_STATE_OPEN
) {
1641 log_info(LD_REND
,"found open intro circ %d (rend %d); sending "
1642 "introduction. (stream %d sec old)",
1643 introcirc
->_base
.n_circ_id
, rendcirc
->_base
.n_circ_id
,
1645 if (rend_client_send_introduction(introcirc
, rendcirc
) < 0) {
1648 rendcirc
->_base
.timestamp_dirty
= time(NULL
);
1649 introcirc
->_base
.timestamp_dirty
= time(NULL
);
1650 assert_circuit_ok(TO_CIRCUIT(rendcirc
));
1651 assert_circuit_ok(TO_CIRCUIT(introcirc
));
1656 log_info(LD_REND
, "Intro (%d) and rend (%d) circs are not both ready. "
1657 "Stalling conn. (%d sec old)",
1658 introcirc
? introcirc
->_base
.n_circ_id
: 0,
1659 rendcirc
? rendcirc
->_base
.n_circ_id
: 0, conn_age
);