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.
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(time_t now
);
35 static void circuit_increment_failure_count(void);
37 long int lround(double x
);
39 /** Return 1 if <b>circ</b> could be returned by circuit_get_best().
43 circuit_is_acceptable(circuit_t
*circ
, edge_connection_t
*conn
,
44 int must_be_open
, uint8_t purpose
,
45 int need_uptime
, int need_internal
,
48 routerinfo_t
*exitrouter
;
49 cpath_build_state_t
*build_state
;
52 tor_assert(conn
->socks_request
);
54 if (!CIRCUIT_IS_ORIGIN(circ
))
55 return 0; /* this circ doesn't start at us */
56 if (must_be_open
&& (circ
->state
!= CIRCUIT_STATE_OPEN
|| !circ
->n_conn
))
57 return 0; /* ignore non-open circs */
58 if (circ
->marked_for_close
)
61 /* if this circ isn't our purpose, skip. */
62 if (purpose
== CIRCUIT_PURPOSE_C_REND_JOINED
&& !must_be_open
) {
63 if (circ
->purpose
!= CIRCUIT_PURPOSE_C_ESTABLISH_REND
&&
64 circ
->purpose
!= CIRCUIT_PURPOSE_C_REND_READY
&&
65 circ
->purpose
!= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
&&
66 circ
->purpose
!= CIRCUIT_PURPOSE_C_REND_JOINED
)
68 } else if (purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
&&
70 if (circ
->purpose
!= CIRCUIT_PURPOSE_C_INTRODUCING
&&
71 circ
->purpose
!= CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
)
74 if (purpose
!= circ
->purpose
)
78 if (purpose
== CIRCUIT_PURPOSE_C_GENERAL
)
79 if (circ
->timestamp_dirty
&&
80 circ
->timestamp_dirty
+get_options()->MaxCircuitDirtiness
<= now
)
83 /* decide if this circ is suitable for this conn */
85 /* for rend circs, circ->cpath->prev is not the last router in the
86 * circuit, it's the magical extra bob hop. so just check the nickname
87 * of the one we meant to finish at.
89 build_state
= TO_ORIGIN_CIRCUIT(circ
)->build_state
;
90 exitrouter
= build_state_get_exit_router(build_state
);
92 if (need_uptime
&& !build_state
->need_uptime
)
94 if (need_internal
!= build_state
->is_internal
)
97 if (purpose
== CIRCUIT_PURPOSE_C_GENERAL
) {
98 if (!exitrouter
&& !build_state
->onehop_tunnel
) {
99 log_debug(LD_CIRC
,"Not considering circuit with unknown router.");
100 return 0; /* this circuit is screwed and doesn't know it yet,
101 * or is a rendezvous circuit. */
103 if (build_state
->onehop_tunnel
) {
104 if (!conn
->want_onehop
) {
105 log_debug(LD_CIRC
,"Skipping one-hop circuit.");
108 tor_assert(conn
->chosen_exit_name
);
109 if (build_state
->chosen_exit
) {
110 char digest
[DIGEST_LEN
];
111 if (hexdigest_to_digest(conn
->chosen_exit_name
, digest
) < 0)
112 return 0; /* broken digest, we don't want it */
113 if (memcmp(digest
, build_state
->chosen_exit
->identity_digest
,
115 return 0; /* this is a circuit to somewhere else */
116 if (tor_digest_is_zero(digest
)) {
117 /* we don't know the digest; have to compare addr:port */
119 int r
= tor_addr_from_str(&addr
, conn
->socks_request
->address
);
121 !tor_addr_eq(&build_state
->chosen_exit
->addr
, &addr
) ||
122 build_state
->chosen_exit
->port
!= conn
->socks_request
->port
)
127 if (conn
->want_onehop
) {
128 /* don't use three-hop circuits -- that could hurt our anonymity. */
132 if (exitrouter
&& !connection_ap_can_use_exit(conn
, exitrouter
, 0)) {
133 /* can't exit from this router */
136 } else { /* not general */
137 origin_circuit_t
*ocirc
= TO_ORIGIN_CIRCUIT(circ
);
138 if ((conn
->rend_data
&& !ocirc
->rend_data
) ||
139 (!conn
->rend_data
&& ocirc
->rend_data
) ||
140 (conn
->rend_data
&& ocirc
->rend_data
&&
141 rend_cmp_service_ids(conn
->rend_data
->onion_address
,
142 ocirc
->rend_data
->onion_address
))) {
143 /* this circ is not for this conn */
150 /** Return 1 if circuit <b>a</b> is better than circuit <b>b</b> for
151 * <b>purpose</b>, and return 0 otherwise. Used by circuit_get_best.
154 circuit_is_better(circuit_t
*a
, circuit_t
*b
, uint8_t purpose
)
157 case CIRCUIT_PURPOSE_C_GENERAL
:
158 /* if it's used but less dirty it's best;
159 * else if it's more recently created it's best
161 if (b
->timestamp_dirty
) {
162 if (a
->timestamp_dirty
&&
163 a
->timestamp_dirty
> b
->timestamp_dirty
)
166 if (a
->timestamp_dirty
||
167 a
->timestamp_created
> b
->timestamp_created
)
169 if (CIRCUIT_IS_ORIGIN(b
) &&
170 TO_ORIGIN_CIRCUIT(b
)->build_state
->is_internal
)
174 case CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
:
175 /* the closer it is to ack_wait the better it is */
176 if (a
->purpose
> b
->purpose
)
179 case CIRCUIT_PURPOSE_C_REND_JOINED
:
180 /* the closer it is to rend_joined the better it is */
181 if (a
->purpose
> b
->purpose
)
188 /** Find the best circ that conn can use, preferably one which is
189 * dirty. Circ must not be too old.
191 * Conn must be defined.
193 * If must_be_open, ignore circs not in CIRCUIT_STATE_OPEN.
195 * circ_purpose specifies what sort of circuit we must have.
196 * It can be C_GENERAL, C_INTRODUCE_ACK_WAIT, or C_REND_JOINED.
198 * If it's REND_JOINED and must_be_open==0, then return the closest
199 * rendezvous-purposed circuit that you can find.
201 * If it's INTRODUCE_ACK_WAIT and must_be_open==0, then return the
202 * closest introduce-purposed circuit that you can find.
204 static origin_circuit_t
*
205 circuit_get_best(edge_connection_t
*conn
, int must_be_open
, uint8_t purpose
,
206 int need_uptime
, int need_internal
)
208 circuit_t
*circ
, *best
=NULL
;
209 time_t now
= time(NULL
);
210 int intro_going_on_but_too_old
= 0;
214 tor_assert(purpose
== CIRCUIT_PURPOSE_C_GENERAL
||
215 purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
||
216 purpose
== CIRCUIT_PURPOSE_C_REND_JOINED
);
218 for (circ
=global_circuitlist
;circ
;circ
= circ
->next
) {
219 if (!circuit_is_acceptable(circ
,conn
,must_be_open
,purpose
,
220 need_uptime
,need_internal
,now
))
223 /* XXX022 make this 15 be a function of circuit finishing times we've
224 * seen lately, a la Fallon Chen's GSoC work -RD */
225 #define REND_PARALLEL_INTRO_DELAY 15
226 if (purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
&&
227 !must_be_open
&& circ
->state
!= CIRCUIT_STATE_OPEN
&&
228 circ
->timestamp_created
+ REND_PARALLEL_INTRO_DELAY
< now
) {
229 intro_going_on_but_too_old
= 1;
233 /* now this is an acceptable circ to hand back. but that doesn't
234 * mean it's the *best* circ to hand back. try to decide.
236 if (!best
|| circuit_is_better(circ
,best
,purpose
))
240 if (!best
&& intro_going_on_but_too_old
)
241 log_info(LD_REND
|LD_CIRC
, "There is an intro circuit being created "
242 "right now, but it has already taken quite a while. Starting "
245 return best
? TO_ORIGIN_CIRCUIT(best
) : NULL
;
248 /** Check whether, according to the policies in <b>options</b>, the
249 * circuit <b>circ</b> makes sense. */
250 /* XXXX currently only checks Exclude{Exit}Nodes. It should check more. */
252 circuit_conforms_to_options(const origin_circuit_t
*circ
,
253 const or_options_t
*options
)
255 const crypt_path_t
*cpath
, *cpath_next
= NULL
;
257 for (cpath
= circ
->cpath
; cpath
&& cpath_next
!= circ
->cpath
;
258 cpath
= cpath_next
) {
259 cpath_next
= cpath
->next
;
261 if (routerset_contains_extendinfo(options
->ExcludeNodes
,
265 if (cpath
->next
== circ
->cpath
) {
266 /* This is apparently the exit node. */
268 if (routerset_contains_extendinfo(options
->ExcludeExitNodes
,
276 /** Close all circuits that start at us, aren't open, and were born
277 * at least CircuitBuildTimeout seconds ago.
280 circuit_expire_building(time_t now
)
282 circuit_t
*victim
, *next_circ
= global_circuitlist
;
283 /* circ_times.timeout is BUILD_TIMEOUT_INITIAL_VALUE if we haven't
284 * decided on a customized one yet */
285 time_t general_cutoff
= now
- lround(circ_times
.timeout_ms
/1000);
286 time_t begindir_cutoff
= now
- lround(circ_times
.timeout_ms
/2000);
287 time_t close_cutoff
= now
- lround(circ_times
.close_ms
/1000);
288 time_t introcirc_cutoff
= begindir_cutoff
;
289 cpath_build_state_t
*build_state
;
294 next_circ
= next_circ
->next
;
295 if (!CIRCUIT_IS_ORIGIN(victim
) || /* didn't originate here */
296 victim
->marked_for_close
) /* don't mess with marked circs */
299 build_state
= TO_ORIGIN_CIRCUIT(victim
)->build_state
;
300 if (build_state
&& build_state
->onehop_tunnel
)
301 cutoff
= begindir_cutoff
;
302 else if (victim
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
)
303 cutoff
= introcirc_cutoff
;
304 else if (victim
->purpose
== CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
)
305 cutoff
= close_cutoff
;
307 cutoff
= general_cutoff
;
309 if (victim
->timestamp_created
> cutoff
)
310 continue; /* it's still young, leave it alone */
313 /* some debug logs, to help track bugs */
314 if (victim
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
&&
315 victim
->timestamp_created
<= introcirc_cutoff
&&
316 victim
->timestamp_created
> general_cutoff
)
317 log_info(LD_REND
|LD_CIRC
, "Timing out introduction circuit which we "
318 "would not have done if it had been a general circuit.");
320 if (victim
->purpose
>= CIRCUIT_PURPOSE_C_INTRODUCING
&&
321 victim
->purpose
<= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
) {
322 if (!victim
->timestamp_dirty
)
323 log_fn(LOG_DEBUG
,"Considering %sopen purpose %d to %s (circid %d)."
325 victim
->state
== CIRCUIT_STATE_OPEN
? "" : "non",
326 victim
->purpose
, victim
->build_state
->chosen_exit_name
,
329 log_fn(LOG_DEBUG
,"Considering %sopen purpose %d to %s (circid %d). "
330 "%d secs since dirty.",
331 victim
->state
== CIRCUIT_STATE_OPEN
? "" : "non",
332 victim
->purpose
, victim
->build_state
->chosen_exit_name
,
334 (int)(now
- victim
->timestamp_dirty
));
338 /* if circ is !open, or if it's open but purpose is a non-finished
339 * intro or rend, then mark it for close */
340 if (victim
->state
== CIRCUIT_STATE_OPEN
) {
341 switch (victim
->purpose
) {
342 default: /* most open circuits can be left alone. */
343 continue; /* yes, continue inside a switch refers to the nearest
344 * enclosing loop. C is smart. */
345 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
346 case CIRCUIT_PURPOSE_C_INTRODUCING
:
347 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
348 break; /* too old, need to die */
349 case CIRCUIT_PURPOSE_C_REND_READY
:
350 /* it's a rend_ready circ -- has it already picked a query? */
351 /* c_rend_ready circs measure age since timestamp_dirty,
352 * because that's set when they switch purposes
354 if (TO_ORIGIN_CIRCUIT(victim
)->rend_data
||
355 victim
->timestamp_dirty
> cutoff
)
358 case CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
:
359 case CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
:
360 /* rend and intro circs become dirty each time they
361 * make an introduction attempt. so timestamp_dirty
362 * will reflect the time since the last attempt.
364 if (victim
->timestamp_dirty
> cutoff
)
368 } else { /* circuit not open, consider recording failure as timeout */
369 int first_hop_succeeded
= TO_ORIGIN_CIRCUIT(victim
)->cpath
&&
370 TO_ORIGIN_CIRCUIT(victim
)->cpath
->state
== CPATH_STATE_OPEN
;
372 if (TO_ORIGIN_CIRCUIT(victim
)->p_streams
!= NULL
) {
373 log_warn(LD_BUG
, "Circuit %d (purpose %d) has timed out, "
374 "yet has attached streams!",
375 TO_ORIGIN_CIRCUIT(victim
)->global_identifier
,
377 tor_fragile_assert();
381 /* circuits are allowed to last longer for measurement.
382 * Switch their purpose and wait. */
383 if (victim
->purpose
!= CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
) {
384 victim
->purpose
= CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
;
385 circuit_build_times_count_timeout(&circ_times
,
386 first_hop_succeeded
);
391 * If the circuit build time is much greater than we would have cut
392 * it off at, we probably had a suspend event along this codepath,
393 * and we should discard the value.
395 if (now
- victim
->timestamp_created
> 2*circ_times
.close_ms
/1000+1) {
397 "Extremely large value for circuit build timeout: %lds. "
398 "Assuming clock jump.",
399 (long)(now
- victim
->timestamp_created
));
400 } else if (circuit_build_times_count_close(&circ_times
,
402 victim
->timestamp_created
)) {
403 circuit_build_times_set_timeout(&circ_times
);
408 log_info(LD_CIRC
,"Abandoning circ %s:%d:%d (state %d:%s, purpose %d)",
409 victim
->n_conn
->_base
.address
, victim
->n_conn
->_base
.port
,
411 victim
->state
, circuit_state_to_string(victim
->state
),
414 log_info(LD_CIRC
,"Abandoning circ %d (state %d:%s, purpose %d)",
415 victim
->n_circ_id
, victim
->state
,
416 circuit_state_to_string(victim
->state
), victim
->purpose
);
418 circuit_log_path(LOG_INFO
,LD_CIRC
,TO_ORIGIN_CIRCUIT(victim
));
419 circuit_mark_for_close(victim
, END_CIRC_REASON_TIMEOUT
);
423 /** Remove any elements in <b>needed_ports</b> that are handled by an
424 * open or in-progress circuit.
427 circuit_remove_handled_ports(smartlist_t
*needed_ports
)
432 for (i
= 0; i
< smartlist_len(needed_ports
); ++i
) {
433 port
= smartlist_get(needed_ports
, i
);
435 if (circuit_stream_is_being_handled(NULL
, *port
,
436 MIN_CIRCUITS_HANDLING_STREAM
)) {
437 // log_debug(LD_CIRC,"Port %d is already being handled; removing.", port);
438 smartlist_del(needed_ports
, i
--);
441 log_debug(LD_CIRC
,"Port %d is not handled.", *port
);
446 /** Return 1 if at least <b>min</b> general-purpose non-internal circuits
447 * will have an acceptable exit node for exit stream <b>conn</b> if it
448 * is defined, else for "*:port".
452 circuit_stream_is_being_handled(edge_connection_t
*conn
,
453 uint16_t port
, int min
)
456 routerinfo_t
*exitrouter
;
458 time_t now
= time(NULL
);
459 int need_uptime
= smartlist_string_num_isin(get_options()->LongLivedPorts
,
460 conn
? conn
->socks_request
->port
: port
);
462 for (circ
=global_circuitlist
;circ
;circ
= circ
->next
) {
463 if (CIRCUIT_IS_ORIGIN(circ
) &&
464 !circ
->marked_for_close
&&
465 circ
->purpose
== CIRCUIT_PURPOSE_C_GENERAL
&&
466 (!circ
->timestamp_dirty
||
467 circ
->timestamp_dirty
+ get_options()->MaxCircuitDirtiness
> now
)) {
468 cpath_build_state_t
*build_state
= TO_ORIGIN_CIRCUIT(circ
)->build_state
;
469 if (build_state
->is_internal
|| build_state
->onehop_tunnel
)
472 exitrouter
= build_state_get_exit_router(build_state
);
473 if (exitrouter
&& (!need_uptime
|| build_state
->need_uptime
)) {
476 ok
= connection_ap_can_use_exit(conn
, exitrouter
, 0);
478 addr_policy_result_t r
= compare_addr_to_addr_policy(
479 0, port
, exitrouter
->exit_policy
);
480 ok
= r
!= ADDR_POLICY_REJECTED
&& r
!= ADDR_POLICY_PROBABLY_REJECTED
;
492 /** Don't keep more than this many unused open circuits around. */
493 #define MAX_UNUSED_OPEN_CIRCUITS 14
495 /** Figure out how many circuits we have open that are clean. Make
496 * sure it's enough for all the upcoming behaviors we predict we'll have.
497 * But put an upper bound on the total number of circuits.
500 circuit_predict_and_launch_new(void)
503 int num
=0, num_internal
=0, num_uptime_internal
=0;
504 int hidserv_needs_uptime
=0, hidserv_needs_capacity
=1;
505 int port_needs_uptime
=0, port_needs_capacity
=1;
506 time_t now
= time(NULL
);
509 /* First, count how many of each type of circuit we have already. */
510 for (circ
=global_circuitlist
;circ
;circ
= circ
->next
) {
511 cpath_build_state_t
*build_state
;
512 if (!CIRCUIT_IS_ORIGIN(circ
))
514 if (circ
->marked_for_close
)
515 continue; /* don't mess with marked circs */
516 if (circ
->timestamp_dirty
)
517 continue; /* only count clean circs */
518 if (circ
->purpose
!= CIRCUIT_PURPOSE_C_GENERAL
)
519 continue; /* only pay attention to general-purpose circs */
520 build_state
= TO_ORIGIN_CIRCUIT(circ
)->build_state
;
521 if (build_state
->onehop_tunnel
)
524 if (build_state
->is_internal
)
526 if (build_state
->need_uptime
&& build_state
->is_internal
)
527 num_uptime_internal
++;
530 /* If that's enough, then stop now. */
531 if (num
>= MAX_UNUSED_OPEN_CIRCUITS
)
532 return; /* we already have many, making more probably will hurt */
534 /* Second, see if we need any more exit circuits. */
535 /* check if we know of a port that's been requested recently
536 * and no circuit is currently available that can handle it. */
537 if (!circuit_all_predicted_ports_handled(now
, &port_needs_uptime
,
538 &port_needs_capacity
)) {
539 if (port_needs_uptime
)
540 flags
|= CIRCLAUNCH_NEED_UPTIME
;
541 if (port_needs_capacity
)
542 flags
|= CIRCLAUNCH_NEED_CAPACITY
;
544 "Have %d clean circs (%d internal), need another exit circ.",
546 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
550 /* Third, see if we need any more hidden service (server) circuits. */
551 if (num_rend_services() && num_uptime_internal
< 3) {
552 flags
= (CIRCLAUNCH_NEED_CAPACITY
| CIRCLAUNCH_NEED_UPTIME
|
553 CIRCLAUNCH_IS_INTERNAL
);
555 "Have %d clean circs (%d internal), need another internal "
556 "circ for my hidden service.",
558 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
562 /* Fourth, see if we need any more hidden service (client) circuits. */
563 if (rep_hist_get_predicted_internal(now
, &hidserv_needs_uptime
,
564 &hidserv_needs_capacity
) &&
565 ((num_uptime_internal
<2 && hidserv_needs_uptime
) ||
567 if (hidserv_needs_uptime
)
568 flags
|= CIRCLAUNCH_NEED_UPTIME
;
569 if (hidserv_needs_capacity
)
570 flags
|= CIRCLAUNCH_NEED_CAPACITY
;
571 flags
|= CIRCLAUNCH_IS_INTERNAL
;
573 "Have %d clean circs (%d uptime-internal, %d internal), need"
574 " another hidden service circ.",
575 num
, num_uptime_internal
, num_internal
);
576 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
580 /* Finally, check to see if we still need more circuits to learn
581 * a good build timeout. But if we're close to our max number we
582 * want, don't do another -- we want to leave a few slots open so
583 * we can still build circuits preemptively as needed. */
584 if (num
< MAX_UNUSED_OPEN_CIRCUITS
-2 &&
585 circuit_build_times_needs_circuits_now(&circ_times
)) {
586 flags
= CIRCLAUNCH_NEED_CAPACITY
;
588 "Have %d clean circs need another buildtime test circ.", num
);
589 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
594 /** Build a new test circuit every 5 minutes */
595 #define TESTING_CIRCUIT_INTERVAL 300
597 /** This function is called once a second, if router_have_min_dir_info() is
598 * true. Its job is to make sure all services we offer have enough circuits
599 * available. Some services just want enough circuits for current tasks,
600 * whereas others want a minimum set of idle circuits hanging around.
603 circuit_build_needed_circs(time_t now
)
605 static time_t time_to_new_circuit
= 0;
606 or_options_t
*options
= get_options();
608 /* launch a new circ for any pending streams that need one */
609 connection_ap_attach_pending();
611 /* make sure any hidden services have enough intro points */
612 rend_services_introduce();
614 if (time_to_new_circuit
< now
) {
615 circuit_reset_failure_count(1);
616 time_to_new_circuit
= now
+ options
->NewCircuitPeriod
;
617 if (proxy_mode(get_options()))
618 addressmap_clean(now
);
619 circuit_expire_old_circuits_clientside(now
);
621 #if 0 /* disable for now, until predict-and-launch-new can cull leftovers */
622 circ
= circuit_get_youngest_clean_open(CIRCUIT_PURPOSE_C_GENERAL
);
623 if (get_options()->RunTesting
&&
625 circ
->timestamp_created
+ TESTING_CIRCUIT_INTERVAL
< now
) {
626 log_fn(LOG_INFO
,"Creating a new testing circuit.");
627 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, 0);
631 if (!options
->DisablePredictedCircuits
)
632 circuit_predict_and_launch_new();
635 /** If the stream <b>conn</b> is a member of any of the linked
636 * lists of <b>circ</b>, then remove it from the list.
639 circuit_detach_stream(circuit_t
*circ
, edge_connection_t
*conn
)
641 edge_connection_t
*prevconn
;
646 conn
->cpath_layer
= NULL
; /* make sure we don't keep a stale pointer */
647 conn
->on_circuit
= NULL
;
649 if (CIRCUIT_IS_ORIGIN(circ
)) {
650 origin_circuit_t
*origin_circ
= TO_ORIGIN_CIRCUIT(circ
);
651 if (conn
== origin_circ
->p_streams
) {
652 origin_circ
->p_streams
= conn
->next_stream
;
656 for (prevconn
= origin_circ
->p_streams
;
657 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
658 prevconn
= prevconn
->next_stream
)
660 if (prevconn
&& prevconn
->next_stream
) {
661 prevconn
->next_stream
= conn
->next_stream
;
665 or_circuit_t
*or_circ
= TO_OR_CIRCUIT(circ
);
666 if (conn
== or_circ
->n_streams
) {
667 or_circ
->n_streams
= conn
->next_stream
;
670 if (conn
== or_circ
->resolving_streams
) {
671 or_circ
->resolving_streams
= conn
->next_stream
;
675 for (prevconn
= or_circ
->n_streams
;
676 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
677 prevconn
= prevconn
->next_stream
)
679 if (prevconn
&& prevconn
->next_stream
) {
680 prevconn
->next_stream
= conn
->next_stream
;
684 for (prevconn
= or_circ
->resolving_streams
;
685 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
686 prevconn
= prevconn
->next_stream
)
688 if (prevconn
&& prevconn
->next_stream
) {
689 prevconn
->next_stream
= conn
->next_stream
;
694 log_warn(LD_BUG
,"Edge connection not in circuit's list.");
695 /* Don't give an error here; it's harmless. */
696 tor_fragile_assert();
699 /** If we haven't yet decided on a good timeout value for circuit
700 * building, we close idles circuits aggressively so we can get more
702 #define IDLE_TIMEOUT_WHILE_LEARNING (10*60)
704 /** Find each circuit that has been unused for too long, or dirty
705 * for too long and has no streams on it: mark it for close.
708 circuit_expire_old_circuits_clientside(time_t now
)
713 if (circuit_build_times_needs_circuits(&circ_times
)) {
714 /* Circuits should be shorter lived if we need more of them
715 * for learning a good build timeout */
716 cutoff
= now
- IDLE_TIMEOUT_WHILE_LEARNING
;
718 cutoff
= now
- get_options()->CircuitIdleTimeout
;
721 for (circ
= global_circuitlist
; circ
; circ
= circ
->next
) {
722 if (circ
->marked_for_close
|| ! CIRCUIT_IS_ORIGIN(circ
))
724 /* If the circuit has been dirty for too long, and there are no streams
725 * on it, mark it for close.
727 if (circ
->timestamp_dirty
&&
728 circ
->timestamp_dirty
+ get_options()->MaxCircuitDirtiness
< now
&&
729 !TO_ORIGIN_CIRCUIT(circ
)->p_streams
/* nothing attached */ ) {
730 log_debug(LD_CIRC
, "Closing n_circ_id %d (dirty %d secs ago, "
732 circ
->n_circ_id
, (int)(now
- circ
->timestamp_dirty
),
734 circuit_mark_for_close(circ
, END_CIRC_REASON_FINISHED
);
735 } else if (!circ
->timestamp_dirty
&& circ
->state
== CIRCUIT_STATE_OPEN
) {
736 if (circ
->timestamp_created
< cutoff
) {
737 if (circ
->purpose
== CIRCUIT_PURPOSE_C_GENERAL
||
738 circ
->purpose
== CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT
||
739 circ
->purpose
== CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
||
740 circ
->purpose
== CIRCUIT_PURPOSE_TESTING
||
741 (circ
->purpose
>= CIRCUIT_PURPOSE_C_INTRODUCING
&&
742 circ
->purpose
<= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
) ||
743 circ
->purpose
== CIRCUIT_PURPOSE_S_CONNECT_REND
) {
745 "Closing circuit that has been unused for %ld seconds.",
746 (long)(now
- circ
->timestamp_created
));
747 circuit_mark_for_close(circ
, END_CIRC_REASON_FINISHED
);
748 } else if (!TO_ORIGIN_CIRCUIT(circ
)->is_ancient
) {
750 "Ancient non-dirty circuit %d is still around after "
751 "%ld seconds. Purpose: %d",
752 TO_ORIGIN_CIRCUIT(circ
)->global_identifier
,
753 (long)(now
- circ
->timestamp_created
),
755 TO_ORIGIN_CIRCUIT(circ
)->is_ancient
= 1;
762 /** How long do we wait before killing circuits with the properties
765 * Probably we could choose a number here as low as 5 to 10 seconds,
766 * since these circs are used for begindir, and a) generally you either
767 * ask another begindir question right after or you don't for a long time,
768 * b) clients at least through 0.2.1.x choose from the whole set of
769 * directory mirrors at each choice, and c) re-establishing a one-hop
770 * circuit via create-fast is a light operation assuming the TLS conn is
773 * I expect "b" to go away one day when we move to using directory
774 * guards, but I think "a" and "c" are good enough reasons that a low
775 * number is safe even then.
777 #define IDLE_ONE_HOP_CIRC_TIMEOUT 60
779 /** Find each non-origin circuit that has been unused for too long,
780 * has no streams on it, used a create_fast, and ends here: mark it
784 circuit_expire_old_circuits_serverside(time_t now
)
787 or_circuit_t
*or_circ
;
788 time_t cutoff
= now
- IDLE_ONE_HOP_CIRC_TIMEOUT
;
790 for (circ
= global_circuitlist
; circ
; circ
= circ
->next
) {
791 if (circ
->marked_for_close
|| CIRCUIT_IS_ORIGIN(circ
))
793 or_circ
= TO_OR_CIRCUIT(circ
);
794 /* If the circuit has been idle for too long, and there are no streams
795 * on it, and it ends here, and it used a create_fast, mark it for close.
797 if (or_circ
->is_first_hop
&& !circ
->n_conn
&&
798 !or_circ
->n_streams
&& !or_circ
->resolving_streams
&&
800 or_circ
->p_conn
->timestamp_last_added_nonpadding
<= cutoff
) {
801 log_info(LD_CIRC
, "Closing circ_id %d (empty %d secs ago)",
803 (int)(now
- or_circ
->p_conn
->timestamp_last_added_nonpadding
));
804 circuit_mark_for_close(circ
, END_CIRC_REASON_FINISHED
);
809 /** Number of testing circuits we want open before testing our bandwidth. */
810 #define NUM_PARALLEL_TESTING_CIRCS 4
812 /** True iff we've ever had enough testing circuits open to test our
814 static int have_performed_bandwidth_test
= 0;
816 /** Reset have_performed_bandwidth_test, so we'll start building
817 * testing circuits again so we can exercise our bandwidth. */
819 reset_bandwidth_test(void)
821 have_performed_bandwidth_test
= 0;
824 /** Return 1 if we've already exercised our bandwidth, or if we
825 * have fewer than NUM_PARALLEL_TESTING_CIRCS testing circuits
826 * established or on the way. Else return 0.
829 circuit_enough_testing_circs(void)
834 if (have_performed_bandwidth_test
)
837 for (circ
= global_circuitlist
; circ
; circ
= circ
->next
) {
838 if (!circ
->marked_for_close
&& CIRCUIT_IS_ORIGIN(circ
) &&
839 circ
->purpose
== CIRCUIT_PURPOSE_TESTING
&&
840 circ
->state
== CIRCUIT_STATE_OPEN
)
843 return num
>= NUM_PARALLEL_TESTING_CIRCS
;
846 /** A testing circuit has completed. Take whatever stats we want.
847 * Noticing reachability is taken care of in onionskin_answer(),
848 * so there's no need to record anything here. But if we still want
849 * to do the bandwidth test, and we now have enough testing circuits
853 circuit_testing_opened(origin_circuit_t
*circ
)
855 if (have_performed_bandwidth_test
||
856 !check_whether_orport_reachable()) {
857 /* either we've already done everything we want with testing circuits,
858 * or this testing circuit became open due to a fluke, e.g. we picked
859 * a last hop where we already had the connection open due to an
860 * outgoing local circuit. */
861 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_AT_ORIGIN
);
862 } else if (circuit_enough_testing_circs()) {
863 router_perform_bandwidth_test(NUM_PARALLEL_TESTING_CIRCS
, time(NULL
));
864 have_performed_bandwidth_test
= 1;
866 consider_testing_reachability(1, 0);
869 /** A testing circuit has failed to build. Take whatever stats we want. */
871 circuit_testing_failed(origin_circuit_t
*circ
, int at_last_hop
)
873 if (server_mode(get_options()) && check_whether_orport_reachable())
877 "Our testing circuit (to see if your ORPort is reachable) "
878 "has failed. I'll try again later.");
880 /* These aren't used yet. */
885 /** The circuit <b>circ</b> has just become open. Take the next
886 * step: for rendezvous circuits, we pass circ to the appropriate
887 * function in rendclient or rendservice. For general circuits, we
888 * call connection_ap_attach_pending, which looks for pending streams
889 * that could use circ.
892 circuit_has_opened(origin_circuit_t
*circ
)
894 control_event_circuit_status(circ
, CIRC_EVENT_BUILT
, 0);
896 switch (TO_CIRCUIT(circ
)->purpose
) {
897 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
898 rend_client_rendcirc_has_opened(circ
);
899 connection_ap_attach_pending();
901 case CIRCUIT_PURPOSE_C_INTRODUCING
:
902 rend_client_introcirc_has_opened(circ
);
904 case CIRCUIT_PURPOSE_C_GENERAL
:
905 /* Tell any AP connections that have been waiting for a new
906 * circuit that one is ready. */
907 connection_ap_attach_pending();
909 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
910 /* at Bob, waiting for introductions */
911 rend_service_intro_has_opened(circ
);
913 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
914 /* at Bob, connecting to rend point */
915 rend_service_rendezvous_has_opened(circ
);
917 case CIRCUIT_PURPOSE_TESTING
:
918 circuit_testing_opened(circ
);
921 * This won't happen in normal operation, but might happen if the
922 * controller did it. Just let it slide. */
926 /** Called whenever a circuit could not be successfully built.
929 circuit_build_failed(origin_circuit_t
*circ
)
931 /* we should examine circ and see if it failed because of
932 * the last hop or an earlier hop. then use this info below.
934 int failed_at_last_hop
= 0;
935 /* If the last hop isn't open, and the second-to-last is, we failed
936 * at the last hop. */
938 circ
->cpath
->prev
->state
!= CPATH_STATE_OPEN
&&
939 circ
->cpath
->prev
->prev
->state
== CPATH_STATE_OPEN
) {
940 failed_at_last_hop
= 1;
943 circ
->cpath
->state
!= CPATH_STATE_OPEN
) {
944 /* We failed at the first hop. If there's an OR connection
945 * to blame, blame it. Also, avoid this relay for a while, and
946 * fail any one-hop directory fetches destined for it. */
947 const char *n_conn_id
= circ
->cpath
->extend_info
->identity_digest
;
948 if (circ
->_base
.n_conn
) {
949 or_connection_t
*n_conn
= circ
->_base
.n_conn
;
951 "Our circuit failed to get a response from the first hop "
952 "(%s:%d). I'm going to try to rotate to a better connection.",
953 n_conn
->_base
.address
, n_conn
->_base
.port
);
954 n_conn
->is_bad_for_new_circs
= 1;
957 "Our circuit died before the first hop with no connection");
960 entry_guard_register_connect_status(n_conn_id
, 0, 1, time(NULL
));
961 /* if there are any one-hop streams waiting on this circuit, fail
962 * them now so they can retry elsewhere. */
963 connection_ap_fail_onehop(n_conn_id
, circ
->build_state
);
967 switch (circ
->_base
.purpose
) {
968 case CIRCUIT_PURPOSE_C_GENERAL
:
969 /* If we never built the circuit, note it as a failure. */
970 circuit_increment_failure_count();
971 if (failed_at_last_hop
) {
972 /* Make sure any streams that demand our last hop as their exit
973 * know that it's unlikely to happen. */
974 circuit_discard_optional_exit_enclaves(circ
->cpath
->prev
->extend_info
);
977 case CIRCUIT_PURPOSE_TESTING
:
978 circuit_testing_failed(circ
, failed_at_last_hop
);
980 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
981 /* at Bob, waiting for introductions */
982 if (circ
->_base
.state
!= CIRCUIT_STATE_OPEN
) {
983 circuit_increment_failure_count();
985 /* no need to care here, because bob will rebuild intro
986 * points periodically. */
988 case CIRCUIT_PURPOSE_C_INTRODUCING
:
989 /* at Alice, connecting to intro point */
990 /* Don't increment failure count, since Bob may have picked
991 * the introduction point maliciously */
992 /* Alice will pick a new intro point when this one dies, if
993 * the stream in question still cares. No need to act here. */
995 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
996 /* at Alice, waiting for Bob */
997 circuit_increment_failure_count();
998 /* Alice will pick a new rend point when this one dies, if
999 * the stream in question still cares. No need to act here. */
1001 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
1002 /* at Bob, connecting to rend point */
1003 /* Don't increment failure count, since Alice may have picked
1004 * the rendezvous point maliciously */
1006 "Couldn't connect to Alice's chosen rend point %s "
1008 escaped(build_state_get_exit_nickname(circ
->build_state
)),
1009 failed_at_last_hop
?"last":"non-last");
1010 rend_service_relaunch_rendezvous(circ
);
1013 * This won't happen in normal operation, but might happen if the
1014 * controller did it. Just let it slide. */
1018 /** Number of consecutive failures so far; should only be touched by
1019 * circuit_launch_new and circuit_*_failure_count.
1021 static int n_circuit_failures
= 0;
1022 /** Before the last time we called circuit_reset_failure_count(), were
1023 * there a lot of failures? */
1024 static int did_circs_fail_last_period
= 0;
1026 /** Don't retry launching a new circuit if we try this many times with no
1028 #define MAX_CIRCUIT_FAILURES 5
1030 /** Launch a new circuit; see circuit_launch_by_extend_info() for
1031 * details on arguments. */
1033 circuit_launch_by_router(uint8_t purpose
,
1034 routerinfo_t
*exit
, int flags
)
1036 origin_circuit_t
*circ
;
1037 extend_info_t
*info
= NULL
;
1039 info
= extend_info_from_router(exit
);
1040 circ
= circuit_launch_by_extend_info(purpose
, info
, flags
);
1042 extend_info_free(info
);
1046 /** Launch a new circuit with purpose <b>purpose</b> and exit node
1047 * <b>extend_info</b> (or NULL to select a random exit node). If flags
1048 * contains CIRCLAUNCH_NEED_UPTIME, choose among routers with high uptime. If
1049 * CIRCLAUNCH_NEED_CAPACITY is set, choose among routers with high bandwidth.
1050 * If CIRCLAUNCH_IS_INTERNAL is true, the last hop need not be an exit node.
1051 * If CIRCLAUNCH_ONEHOP_TUNNEL is set, the circuit will have only one hop.
1052 * Return the newly allocated circuit on success, or NULL on failure. */
1054 circuit_launch_by_extend_info(uint8_t purpose
,
1055 extend_info_t
*extend_info
,
1058 origin_circuit_t
*circ
;
1059 int onehop_tunnel
= (flags
& CIRCLAUNCH_ONEHOP_TUNNEL
) != 0;
1061 if (!onehop_tunnel
&& !router_have_minimum_dir_info()) {
1062 log_debug(LD_CIRC
,"Haven't fetched enough directory info yet; canceling "
1067 if ((extend_info
|| purpose
!= CIRCUIT_PURPOSE_C_GENERAL
) &&
1068 purpose
!= CIRCUIT_PURPOSE_TESTING
&& !onehop_tunnel
) {
1069 /* see if there are appropriate circs available to cannibalize. */
1070 /* XXX if we're planning to add a hop, perhaps we want to look for
1071 * internal circs rather than exit circs? -RD */
1072 circ
= circuit_find_to_cannibalize(purpose
, extend_info
, flags
);
1074 log_info(LD_CIRC
,"Cannibalizing circ '%s' for purpose %d",
1075 build_state_get_exit_nickname(circ
->build_state
), purpose
);
1076 circ
->_base
.purpose
= purpose
;
1077 /* reset the birth date of this circ, else expire_building
1078 * will see it and think it's been trying to build since it
1080 circ
->_base
.timestamp_created
= time(NULL
);
1082 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
1083 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
1084 /* it's ready right now */
1086 case CIRCUIT_PURPOSE_C_INTRODUCING
:
1087 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
1088 case CIRCUIT_PURPOSE_C_GENERAL
:
1089 /* need to add a new hop */
1090 tor_assert(extend_info
);
1091 if (circuit_extend_to_new_exit(circ
, extend_info
) < 0)
1096 "unexpected purpose %d when cannibalizing a circ.",
1098 tor_fragile_assert();
1105 if (did_circs_fail_last_period
&&
1106 n_circuit_failures
> MAX_CIRCUIT_FAILURES
) {
1107 /* too many failed circs in a row. don't try. */
1108 // log_fn(LOG_INFO,"%d failures so far, not trying.",n_circuit_failures);
1112 /* try a circ. if it fails, circuit_mark_for_close will increment
1113 * n_circuit_failures */
1114 return circuit_establish_circuit(purpose
, extend_info
, flags
);
1117 /** Record another failure at opening a general circuit. When we have
1118 * too many, we'll stop trying for the remainder of this minute.
1121 circuit_increment_failure_count(void)
1123 ++n_circuit_failures
;
1124 log_debug(LD_CIRC
,"n_circuit_failures now %d.",n_circuit_failures
);
1127 /** Reset the failure count for opening general circuits. This means
1128 * we will try MAX_CIRCUIT_FAILURES times more (if necessary) before
1132 circuit_reset_failure_count(int timeout
)
1134 if (timeout
&& n_circuit_failures
> MAX_CIRCUIT_FAILURES
)
1135 did_circs_fail_last_period
= 1;
1137 did_circs_fail_last_period
= 0;
1138 n_circuit_failures
= 0;
1141 /** Find an open circ that we're happy to use for <b>conn</b> and return 1. If
1142 * there isn't one, and there isn't one on the way, launch one and return
1143 * 0. If it will never work, return -1.
1145 * Write the found or in-progress or launched circ into *circp.
1148 circuit_get_open_circ_or_launch(edge_connection_t
*conn
,
1149 uint8_t desired_circuit_purpose
,
1150 origin_circuit_t
**circp
)
1152 origin_circuit_t
*circ
;
1153 int check_exit_policy
;
1154 int need_uptime
, need_internal
;
1156 or_options_t
*options
= get_options();
1160 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
);
1162 conn
->socks_request
->command
== SOCKS_COMMAND_CONNECT
&&
1163 !conn
->use_begindir
&&
1164 !connection_edge_is_rendezvous_stream(conn
);
1165 want_onehop
= conn
->want_onehop
;
1167 need_uptime
= !conn
->want_onehop
&& !conn
->use_begindir
&&
1168 smartlist_string_num_isin(options
->LongLivedPorts
,
1169 conn
->socks_request
->port
);
1170 need_internal
= desired_circuit_purpose
!= CIRCUIT_PURPOSE_C_GENERAL
;
1172 circ
= circuit_get_best(conn
, 1, desired_circuit_purpose
,
1173 need_uptime
, need_internal
);
1177 return 1; /* we're happy */
1180 if (!want_onehop
&& !router_have_minimum_dir_info()) {
1181 if (!connection_get_by_type(CONN_TYPE_DIR
)) {
1182 int severity
= LOG_NOTICE
;
1183 /* FFFF if this is a tunneled directory fetch, don't yell
1184 * as loudly. the user doesn't even know it's happening. */
1185 if (options
->UseBridges
&& bridges_known_but_down()) {
1186 log_fn(severity
, LD_APP
|LD_DIR
,
1187 "Application request when we're believed to be "
1188 "offline. Optimistically trying known bridges again.");
1189 bridges_retry_all();
1190 } else if (!options
->UseBridges
|| any_bridge_descriptors_known()) {
1191 log_fn(severity
, LD_APP
|LD_DIR
,
1192 "Application request when we're believed to be "
1193 "offline. Optimistically trying directory fetches again.");
1194 routerlist_retry_directory_downloads(time(NULL
));
1197 /* the stream will be dealt with when router_have_minimum_dir_info becomes
1198 * 1, or when all directory attempts fail and directory_all_unreachable()
1204 /* Do we need to check exit policy? */
1205 if (check_exit_policy
) {
1206 if (!conn
->chosen_exit_name
) {
1209 if (tor_inet_aton(conn
->socks_request
->address
, &in
))
1210 addr
= ntohl(in
.s_addr
);
1211 if (router_exit_policy_all_routers_reject(addr
,
1212 conn
->socks_request
->port
,
1215 "No Tor server allows exit to %s:%d. Rejecting.",
1216 safe_str_client(conn
->socks_request
->address
),
1217 conn
->socks_request
->port
);
1221 /* XXXX022 Duplicates checks in connection_ap_handshake_attach_circuit */
1222 routerinfo_t
*router
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1223 int opt
= conn
->chosen_exit_optional
;
1224 if (router
&& !connection_ap_can_use_exit(conn
, router
, 0)) {
1225 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1226 "Requested exit point '%s' would refuse request. %s.",
1227 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1229 conn
->chosen_exit_optional
= 0;
1230 tor_free(conn
->chosen_exit_name
);
1232 return circuit_get_open_circ_or_launch(conn
,
1233 desired_circuit_purpose
,
1241 /* is one already on the way? */
1242 circ
= circuit_get_best(conn
, 0, desired_circuit_purpose
,
1243 need_uptime
, need_internal
);
1245 log_debug(LD_CIRC
, "one on the way!");
1247 extend_info_t
*extend_info
=NULL
;
1248 uint8_t new_circ_purpose
;
1250 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
) {
1251 /* need to pick an intro point */
1252 tor_assert(conn
->rend_data
);
1253 extend_info
= rend_client_get_random_intro(conn
->rend_data
);
1256 "No intro points for '%s': re-fetching service descriptor.",
1257 safe_str_client(conn
->rend_data
->onion_address
));
1258 rend_client_refetch_v2_renddesc(conn
->rend_data
);
1259 conn
->_base
.state
= AP_CONN_STATE_RENDDESC_WAIT
;
1262 log_info(LD_REND
,"Chose '%s' as intro point for '%s'.",
1263 extend_info
->nickname
,
1264 safe_str_client(conn
->rend_data
->onion_address
));
1267 /* If we have specified a particular exit node for our
1268 * connection, then be sure to open a circuit to that exit node.
1270 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_GENERAL
) {
1271 if (conn
->chosen_exit_name
) {
1273 int opt
= conn
->chosen_exit_optional
;
1274 r
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1276 extend_info
= extend_info_from_router(r
);
1278 log_debug(LD_DIR
, "considering %d, %s",
1279 want_onehop
, conn
->chosen_exit_name
);
1280 if (want_onehop
&& conn
->chosen_exit_name
[0] == '$') {
1281 /* We're asking for a one-hop circuit to a router that
1282 * we don't have a routerinfo about. Make up an extend_info. */
1283 char digest
[DIGEST_LEN
];
1284 char *hexdigest
= conn
->chosen_exit_name
+1;
1286 if (strlen(hexdigest
) < HEX_DIGEST_LEN
||
1287 base16_decode(digest
,DIGEST_LEN
,hexdigest
,HEX_DIGEST_LEN
)<0) {
1288 log_info(LD_DIR
, "Broken exit digest on tunnel conn. Closing.");
1291 if (tor_addr_from_str(&addr
, conn
->socks_request
->address
) < 0) {
1292 log_info(LD_DIR
, "Broken address %s on tunnel conn. Closing.",
1293 escaped_safe_str_client(conn
->socks_request
->address
));
1296 extend_info
= extend_info_alloc(conn
->chosen_exit_name
+1,
1297 digest
, NULL
, &addr
,
1298 conn
->socks_request
->port
);
1300 /* We will need an onion key for the router, and we
1301 * don't have one. Refuse or relax requirements. */
1302 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1303 "Requested exit point '%s' is not known. %s.",
1304 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1306 conn
->chosen_exit_optional
= 0;
1307 tor_free(conn
->chosen_exit_name
);
1308 /* Try again with no requested exit */
1309 return circuit_get_open_circ_or_launch(conn
,
1310 desired_circuit_purpose
,
1319 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_REND_JOINED
)
1320 new_circ_purpose
= CIRCUIT_PURPOSE_C_ESTABLISH_REND
;
1321 else if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
)
1322 new_circ_purpose
= CIRCUIT_PURPOSE_C_INTRODUCING
;
1324 new_circ_purpose
= desired_circuit_purpose
;
1327 int flags
= CIRCLAUNCH_NEED_CAPACITY
;
1328 if (want_onehop
) flags
|= CIRCLAUNCH_ONEHOP_TUNNEL
;
1329 if (need_uptime
) flags
|= CIRCLAUNCH_NEED_UPTIME
;
1330 if (need_internal
) flags
|= CIRCLAUNCH_IS_INTERNAL
;
1331 circ
= circuit_launch_by_extend_info(new_circ_purpose
, extend_info
,
1335 extend_info_free(extend_info
);
1337 if (desired_circuit_purpose
!= CIRCUIT_PURPOSE_C_GENERAL
) {
1338 /* help predict this next time */
1339 rep_hist_note_used_internal(time(NULL
), need_uptime
, 1);
1341 /* write the service_id into circ */
1342 circ
->rend_data
= rend_data_dup(conn
->rend_data
);
1343 if (circ
->_base
.purpose
== CIRCUIT_PURPOSE_C_ESTABLISH_REND
&&
1344 circ
->_base
.state
== CIRCUIT_STATE_OPEN
)
1345 rend_client_rendcirc_has_opened(circ
);
1351 "No safe circuit (purpose %d) ready for edge "
1352 "connection; delaying.",
1353 desired_circuit_purpose
);
1358 /** Return true iff <b>crypt_path</b> is one of the crypt_paths for
1361 cpath_is_on_circuit(origin_circuit_t
*circ
, crypt_path_t
*crypt_path
)
1363 crypt_path_t
*cpath
, *cpath_next
= NULL
;
1364 for (cpath
= circ
->cpath
; cpath_next
!= circ
->cpath
; cpath
= cpath_next
) {
1365 cpath_next
= cpath
->next
;
1366 if (crypt_path
== cpath
)
1372 /** Attach the AP stream <b>apconn</b> to circ's linked list of
1373 * p_streams. Also set apconn's cpath_layer to <b>cpath</b>, or to the last
1374 * hop in circ's cpath if <b>cpath</b> is NULL.
1377 link_apconn_to_circ(edge_connection_t
*apconn
, origin_circuit_t
*circ
,
1378 crypt_path_t
*cpath
)
1380 /* add it into the linked list of streams on this circuit */
1381 log_debug(LD_APP
|LD_CIRC
, "attaching new conn to circ. n_circ_id %d.",
1382 circ
->_base
.n_circ_id
);
1383 /* reset it, so we can measure circ timeouts */
1384 apconn
->_base
.timestamp_lastread
= time(NULL
);
1385 apconn
->next_stream
= circ
->p_streams
;
1386 apconn
->on_circuit
= TO_CIRCUIT(circ
);
1387 /* assert_connection_ok(conn, time(NULL)); */
1388 circ
->p_streams
= apconn
;
1390 if (cpath
) { /* we were given one; use it */
1391 tor_assert(cpath_is_on_circuit(circ
, cpath
));
1392 apconn
->cpath_layer
= cpath
;
1393 } else { /* use the last hop in the circuit */
1394 tor_assert(circ
->cpath
);
1395 tor_assert(circ
->cpath
->prev
);
1396 tor_assert(circ
->cpath
->prev
->state
== CPATH_STATE_OPEN
);
1397 apconn
->cpath_layer
= circ
->cpath
->prev
;
1401 /** If an exit wasn't specifically chosen, save the history for future
1404 consider_recording_trackhost(edge_connection_t
*conn
, origin_circuit_t
*circ
)
1406 int found_needle
= 0;
1407 or_options_t
*options
= get_options();
1410 char fp
[HEX_DIGEST_LEN
+1];
1412 /* Search the addressmap for this conn's destination. */
1413 /* If he's not in the address map.. */
1414 if (!options
->TrackHostExits
||
1415 addressmap_have_mapping(conn
->socks_request
->address
,
1416 options
->TrackHostExitsExpire
))
1417 return; /* nothing to track, or already mapped */
1419 SMARTLIST_FOREACH(options
->TrackHostExits
, const char *, cp
, {
1420 if (cp
[0] == '.') { /* match end */
1421 if (cp
[1] == '\0' ||
1422 !strcasecmpend(conn
->socks_request
->address
, cp
) ||
1423 !strcasecmp(conn
->socks_request
->address
, &cp
[1]))
1425 } else if (strcasecmp(cp
, conn
->socks_request
->address
) == 0) {
1430 if (!found_needle
|| !circ
->build_state
->chosen_exit
)
1433 /* write down the fingerprint of the chosen exit, not the nickname,
1434 * because the chosen exit might not be named. */
1435 base16_encode(fp
, sizeof(fp
),
1436 circ
->build_state
->chosen_exit
->identity_digest
, DIGEST_LEN
);
1438 /* Add this exit/hostname pair to the addressmap. */
1439 len
= strlen(conn
->socks_request
->address
) + 1 /* '.' */ +
1440 strlen(fp
) + 1 /* '.' */ +
1441 strlen("exit") + 1 /* '\0' */;
1442 new_address
= tor_malloc(len
);
1444 tor_snprintf(new_address
, len
, "%s.%s.exit",
1445 conn
->socks_request
->address
, fp
);
1447 addressmap_register(conn
->socks_request
->address
, new_address
,
1448 time(NULL
) + options
->TrackHostExitsExpire
,
1449 ADDRMAPSRC_TRACKEXIT
);
1452 /** Attempt to attach the connection <b>conn</b> to <b>circ</b>, and send a
1453 * begin or resolve cell as appropriate. Return values are as for
1454 * connection_ap_handshake_attach_circuit. The stream will exit from the hop
1455 * indicated by <b>cpath</b>, or from the last hop in circ's cpath if
1456 * <b>cpath</b> is NULL. */
1458 connection_ap_handshake_attach_chosen_circuit(edge_connection_t
*conn
,
1459 origin_circuit_t
*circ
,
1460 crypt_path_t
*cpath
)
1463 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
||
1464 conn
->_base
.state
== AP_CONN_STATE_CONTROLLER_WAIT
);
1465 tor_assert(conn
->socks_request
);
1467 tor_assert(circ
->_base
.state
== CIRCUIT_STATE_OPEN
);
1469 conn
->_base
.state
= AP_CONN_STATE_CIRCUIT_WAIT
;
1471 if (!circ
->_base
.timestamp_dirty
)
1472 circ
->_base
.timestamp_dirty
= time(NULL
);
1474 link_apconn_to_circ(conn
, circ
, cpath
);
1475 tor_assert(conn
->socks_request
);
1476 if (conn
->socks_request
->command
== SOCKS_COMMAND_CONNECT
) {
1477 if (!conn
->use_begindir
)
1478 consider_recording_trackhost(conn
, circ
);
1479 if (connection_ap_handshake_send_begin(conn
) < 0)
1482 if (connection_ap_handshake_send_resolve(conn
) < 0)
1489 /** Try to find a safe live circuit for CONN_TYPE_AP connection conn. If
1490 * we don't find one: if conn cannot be handled by any known nodes,
1491 * warn and return -1 (conn needs to die, and is maybe already marked);
1492 * else launch new circuit (if necessary) and return 0.
1493 * Otherwise, associate conn with a safe live circuit, do the
1494 * right next step, and return 1.
1496 /* XXXX this function should mark for close whenever it returns -1;
1497 * its callers shouldn't have to worry about that. */
1499 connection_ap_handshake_attach_circuit(edge_connection_t
*conn
)
1506 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
);
1507 tor_assert(conn
->socks_request
);
1508 want_onehop
= conn
->want_onehop
;
1510 conn_age
= (int)(time(NULL
) - conn
->_base
.timestamp_created
);
1512 if (conn_age
>= get_options()->SocksTimeout
) {
1513 int severity
= (tor_addr_is_null(&conn
->_base
.addr
) && !conn
->_base
.port
) ?
1514 LOG_INFO
: LOG_NOTICE
;
1515 log_fn(severity
, LD_APP
,
1516 "Tried for %d seconds to get a connection to %s:%d. Giving up.",
1517 conn_age
, safe_str_client(conn
->socks_request
->address
),
1518 conn
->socks_request
->port
);
1522 if (!connection_edge_is_rendezvous_stream(conn
)) { /* we're a general conn */
1523 origin_circuit_t
*circ
=NULL
;
1525 if (conn
->chosen_exit_name
) {
1526 routerinfo_t
*router
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1527 int opt
= conn
->chosen_exit_optional
;
1528 if (!router
&& !want_onehop
) {
1529 /* We ran into this warning when trying to extend a circuit to a
1530 * hidden service directory for which we didn't have a router
1531 * descriptor. See flyspray task 767 for more details. We should
1532 * keep this in mind when deciding to use BEGIN_DIR cells for other
1533 * directory requests as well. -KL*/
1534 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1535 "Requested exit point '%s' is not known. %s.",
1536 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1538 conn
->chosen_exit_optional
= 0;
1539 tor_free(conn
->chosen_exit_name
);
1544 if (router
&& !connection_ap_can_use_exit(conn
, router
, 0)) {
1545 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1546 "Requested exit point '%s' would refuse request. %s.",
1547 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1549 conn
->chosen_exit_optional
= 0;
1550 tor_free(conn
->chosen_exit_name
);
1557 /* find the circuit that we should use, if there is one. */
1558 retval
= circuit_get_open_circ_or_launch(
1559 conn
, CIRCUIT_PURPOSE_C_GENERAL
, &circ
);
1560 if (retval
< 1) // XXX021 if we totally fail, this still returns 0 -RD
1563 log_debug(LD_APP
|LD_CIRC
,
1564 "Attaching apconn to circ %d (stream %d sec old).",
1565 circ
->_base
.n_circ_id
, conn_age
);
1566 /* print the circ's path, so people can figure out which circs are
1568 circuit_log_path(LOG_INFO
,LD_APP
|LD_CIRC
,circ
);
1570 /* We have found a suitable circuit for our conn. Hurray. */
1571 return connection_ap_handshake_attach_chosen_circuit(conn
, circ
, NULL
);
1573 } else { /* we're a rendezvous conn */
1574 origin_circuit_t
*rendcirc
=NULL
, *introcirc
=NULL
;
1576 tor_assert(!conn
->cpath_layer
);
1578 /* start by finding a rendezvous circuit for us */
1580 retval
= circuit_get_open_circ_or_launch(
1581 conn
, CIRCUIT_PURPOSE_C_REND_JOINED
, &rendcirc
);
1582 if (retval
< 0) return -1; /* failed */
1585 tor_assert(rendcirc
);
1586 /* one is already established, attach */
1588 "rend joined circ %d already here. attaching. "
1589 "(stream %d sec old)",
1590 rendcirc
->_base
.n_circ_id
, conn_age
);
1591 /* Mark rendezvous circuits as 'newly dirty' every time you use
1592 * them, since the process of rebuilding a rendezvous circ is so
1593 * expensive. There is a tradeoff between linkability and
1594 * feasibility, at this point.
1596 rendcirc
->_base
.timestamp_dirty
= time(NULL
);
1597 link_apconn_to_circ(conn
, rendcirc
, NULL
);
1598 if (connection_ap_handshake_send_begin(conn
) < 0)
1599 return 0; /* already marked, let them fade away */
1603 if (rendcirc
&& (rendcirc
->_base
.purpose
==
1604 CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
)) {
1606 "pending-join circ %d already here, with intro ack. "
1607 "Stalling. (stream %d sec old)",
1608 rendcirc
->_base
.n_circ_id
, conn_age
);
1612 /* it's on its way. find an intro circ. */
1613 retval
= circuit_get_open_circ_or_launch(
1614 conn
, CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
, &introcirc
);
1615 if (retval
< 0) return -1; /* failed */
1618 /* one has already sent the intro. keep waiting. */
1619 circuit_t
*c
= NULL
;
1620 tor_assert(introcirc
);
1621 log_info(LD_REND
, "Intro circ %d present and awaiting ack (rend %d). "
1622 "Stalling. (stream %d sec old)",
1623 introcirc
->_base
.n_circ_id
,
1624 rendcirc
? rendcirc
->_base
.n_circ_id
: 0,
1626 /* abort parallel intro circs, if any */
1627 for (c
= global_circuitlist
; c
; c
= c
->next
) {
1628 if (c
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
&&
1629 !c
->marked_for_close
&& CIRCUIT_IS_ORIGIN(c
)) {
1630 origin_circuit_t
*oc
= TO_ORIGIN_CIRCUIT(c
);
1631 if (oc
->rend_data
&&
1632 !rend_cmp_service_ids(conn
->rend_data
->onion_address
,
1633 oc
->rend_data
->onion_address
)) {
1634 log_info(LD_REND
|LD_CIRC
, "Closing introduction circuit that we "
1635 "built in parallel.");
1636 circuit_mark_for_close(c
, END_CIRC_REASON_TIMEOUT
);
1643 /* now rendcirc and introcirc are each either undefined or not finished */
1645 if (rendcirc
&& introcirc
&&
1646 rendcirc
->_base
.purpose
== CIRCUIT_PURPOSE_C_REND_READY
) {
1648 "ready rend circ %d already here (no intro-ack yet on "
1649 "intro %d). (stream %d sec old)",
1650 rendcirc
->_base
.n_circ_id
,
1651 introcirc
->_base
.n_circ_id
, conn_age
);
1653 tor_assert(introcirc
->_base
.purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
);
1654 if (introcirc
->_base
.state
== CIRCUIT_STATE_OPEN
) {
1655 log_info(LD_REND
,"found open intro circ %d (rend %d); sending "
1656 "introduction. (stream %d sec old)",
1657 introcirc
->_base
.n_circ_id
, rendcirc
->_base
.n_circ_id
,
1659 if (rend_client_send_introduction(introcirc
, rendcirc
) < 0) {
1662 rendcirc
->_base
.timestamp_dirty
= time(NULL
);
1663 introcirc
->_base
.timestamp_dirty
= time(NULL
);
1664 assert_circuit_ok(TO_CIRCUIT(rendcirc
));
1665 assert_circuit_ok(TO_CIRCUIT(introcirc
));
1670 log_info(LD_REND
, "Intro (%d) and rend (%d) circs are not both ready. "
1671 "Stalling conn. (%d sec old)",
1672 introcirc
? introcirc
->_base
.n_circ_id
: 0,
1673 rendcirc
? rendcirc
->_base
.n_circ_id
: 0, conn_age
);