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) 2007-2009, 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(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 introcirc_cutoff
= begindir_cutoff
;
274 cpath_build_state_t
*build_state
;
279 next_circ
= next_circ
->next
;
280 if (!CIRCUIT_IS_ORIGIN(victim
) || /* didn't originate here */
281 victim
->marked_for_close
) /* don't mess with marked circs */
284 build_state
= TO_ORIGIN_CIRCUIT(victim
)->build_state
;
285 if (build_state
&& build_state
->onehop_tunnel
)
286 cutoff
= begindir_cutoff
;
287 else if (victim
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
)
288 cutoff
= introcirc_cutoff
;
290 cutoff
= general_cutoff
;
291 if (victim
->timestamp_created
> cutoff
)
292 continue; /* it's still young, leave it alone */
295 /* some debug logs, to help track bugs */
296 if (victim
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
&&
297 victim
->timestamp_created
<= introcirc_cutoff
&&
298 victim
->timestamp_created
> general_cutoff
)
299 log_info(LD_REND
|LD_CIRC
, "Timing out introduction circuit which we "
300 "would not have done if it had been a general circuit.");
302 if (victim
->purpose
>= CIRCUIT_PURPOSE_C_INTRODUCING
&&
303 victim
->purpose
<= CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
) {
304 if (!victim
->timestamp_dirty
)
305 log_fn(LOG_DEBUG
,"Considering %sopen purpose %d to %s (circid %d)."
307 victim
->state
== CIRCUIT_STATE_OPEN
? "" : "non",
308 victim
->purpose
, victim
->build_state
->chosen_exit_name
,
311 log_fn(LOG_DEBUG
,"Considering %sopen purpose %d to %s (circid %d). "
312 "%d secs since dirty.",
313 victim
->state
== CIRCUIT_STATE_OPEN
? "" : "non",
314 victim
->purpose
, victim
->build_state
->chosen_exit_name
,
316 (int)(now
- victim
->timestamp_dirty
));
320 /* if circ is !open, or if it's open but purpose is a non-finished
321 * intro or rend, then mark it for close */
322 if (victim
->state
== CIRCUIT_STATE_OPEN
) {
323 switch (victim
->purpose
) {
324 default: /* most open circuits can be left alone. */
325 continue; /* yes, continue inside a switch refers to the nearest
326 * enclosing loop. C is smart. */
327 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
328 case CIRCUIT_PURPOSE_C_INTRODUCING
:
329 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
330 break; /* too old, need to die */
331 case CIRCUIT_PURPOSE_C_REND_READY
:
332 /* it's a rend_ready circ -- has it already picked a query? */
333 /* c_rend_ready circs measure age since timestamp_dirty,
334 * because that's set when they switch purposes
336 if (TO_ORIGIN_CIRCUIT(victim
)->rend_data
||
337 victim
->timestamp_dirty
> cutoff
)
340 case CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
:
341 case CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
:
342 /* rend and intro circs become dirty each time they
343 * make an introduction attempt. so timestamp_dirty
344 * will reflect the time since the last attempt.
346 if (victim
->timestamp_dirty
> cutoff
)
350 } else { /* circuit not open, consider recording failure as timeout */
351 int first_hop_succeeded
= TO_ORIGIN_CIRCUIT(victim
)->cpath
&&
352 TO_ORIGIN_CIRCUIT(victim
)->cpath
->state
== CPATH_STATE_OPEN
;
353 if (circuit_build_times_add_timeout(&circ_times
, first_hop_succeeded
,
354 victim
->timestamp_created
))
355 circuit_build_times_set_timeout(&circ_times
);
359 log_info(LD_CIRC
,"Abandoning circ %s:%d:%d (state %d:%s, purpose %d)",
360 victim
->n_conn
->_base
.address
, victim
->n_conn
->_base
.port
,
362 victim
->state
, circuit_state_to_string(victim
->state
),
365 log_info(LD_CIRC
,"Abandoning circ %d (state %d:%s, purpose %d)",
366 victim
->n_circ_id
, victim
->state
,
367 circuit_state_to_string(victim
->state
), victim
->purpose
);
369 circuit_log_path(LOG_INFO
,LD_CIRC
,TO_ORIGIN_CIRCUIT(victim
));
370 circuit_mark_for_close(victim
, END_CIRC_REASON_TIMEOUT
);
374 /** Remove any elements in <b>needed_ports</b> that are handled by an
375 * open or in-progress circuit.
378 circuit_remove_handled_ports(smartlist_t
*needed_ports
)
383 for (i
= 0; i
< smartlist_len(needed_ports
); ++i
) {
384 port
= smartlist_get(needed_ports
, i
);
386 if (circuit_stream_is_being_handled(NULL
, *port
,
387 MIN_CIRCUITS_HANDLING_STREAM
)) {
388 // log_debug(LD_CIRC,"Port %d is already being handled; removing.", port);
389 smartlist_del(needed_ports
, i
--);
392 log_debug(LD_CIRC
,"Port %d is not handled.", *port
);
397 /** Return 1 if at least <b>min</b> general-purpose non-internal circuits
398 * will have an acceptable exit node for exit stream <b>conn</b> if it
399 * is defined, else for "*:port".
403 circuit_stream_is_being_handled(edge_connection_t
*conn
,
404 uint16_t port
, int min
)
407 routerinfo_t
*exitrouter
;
409 time_t now
= time(NULL
);
410 int need_uptime
= smartlist_string_num_isin(get_options()->LongLivedPorts
,
411 conn
? conn
->socks_request
->port
: port
);
413 for (circ
=global_circuitlist
;circ
;circ
= circ
->next
) {
414 if (CIRCUIT_IS_ORIGIN(circ
) &&
415 !circ
->marked_for_close
&&
416 circ
->purpose
== CIRCUIT_PURPOSE_C_GENERAL
&&
417 (!circ
->timestamp_dirty
||
418 circ
->timestamp_dirty
+ get_options()->MaxCircuitDirtiness
> now
)) {
419 cpath_build_state_t
*build_state
= TO_ORIGIN_CIRCUIT(circ
)->build_state
;
420 if (build_state
->is_internal
|| build_state
->onehop_tunnel
)
423 exitrouter
= build_state_get_exit_router(build_state
);
424 if (exitrouter
&& (!need_uptime
|| build_state
->need_uptime
)) {
427 ok
= connection_ap_can_use_exit(conn
, exitrouter
, 0);
429 addr_policy_result_t r
= compare_addr_to_addr_policy(
430 0, port
, exitrouter
->exit_policy
);
431 ok
= r
!= ADDR_POLICY_REJECTED
&& r
!= ADDR_POLICY_PROBABLY_REJECTED
;
443 /** Don't keep more than this many unused open circuits around. */
444 #define MAX_UNUSED_OPEN_CIRCUITS 14
446 /** Figure out how many circuits we have open that are clean. Make
447 * sure it's enough for all the upcoming behaviors we predict we'll have.
448 * But put an upper bound on the total number of circuits.
451 circuit_predict_and_launch_new(void)
454 int num
=0, num_internal
=0, num_uptime_internal
=0;
455 int hidserv_needs_uptime
=0, hidserv_needs_capacity
=1;
456 int port_needs_uptime
=0, port_needs_capacity
=1;
457 time_t now
= time(NULL
);
460 /* First, count how many of each type of circuit we have already. */
461 for (circ
=global_circuitlist
;circ
;circ
= circ
->next
) {
462 cpath_build_state_t
*build_state
;
463 if (!CIRCUIT_IS_ORIGIN(circ
))
465 if (circ
->marked_for_close
)
466 continue; /* don't mess with marked circs */
467 if (circ
->timestamp_dirty
)
468 continue; /* only count clean circs */
469 if (circ
->purpose
!= CIRCUIT_PURPOSE_C_GENERAL
)
470 continue; /* only pay attention to general-purpose circs */
471 build_state
= TO_ORIGIN_CIRCUIT(circ
)->build_state
;
472 if (build_state
->onehop_tunnel
)
475 if (build_state
->is_internal
)
477 if (build_state
->need_uptime
&& build_state
->is_internal
)
478 num_uptime_internal
++;
481 /* If that's enough, then stop now. */
482 if (num
>= MAX_UNUSED_OPEN_CIRCUITS
)
483 return; /* we already have many, making more probably will hurt */
485 /* Second, see if we need any more exit circuits. */
486 /* check if we know of a port that's been requested recently
487 * and no circuit is currently available that can handle it. */
488 if (!circuit_all_predicted_ports_handled(now
, &port_needs_uptime
,
489 &port_needs_capacity
)) {
490 if (port_needs_uptime
)
491 flags
|= CIRCLAUNCH_NEED_UPTIME
;
492 if (port_needs_capacity
)
493 flags
|= CIRCLAUNCH_NEED_CAPACITY
;
495 "Have %d clean circs (%d internal), need another exit circ.",
497 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
501 /* Third, see if we need any more hidden service (server) circuits. */
502 if (num_rend_services() && num_uptime_internal
< 3) {
503 flags
= (CIRCLAUNCH_NEED_CAPACITY
| CIRCLAUNCH_NEED_UPTIME
|
504 CIRCLAUNCH_IS_INTERNAL
);
506 "Have %d clean circs (%d internal), need another internal "
507 "circ for my hidden service.",
509 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
513 /* Fourth, see if we need any more hidden service (client) circuits. */
514 if (rep_hist_get_predicted_internal(now
, &hidserv_needs_uptime
,
515 &hidserv_needs_capacity
) &&
516 ((num_uptime_internal
<2 && hidserv_needs_uptime
) ||
518 if (hidserv_needs_uptime
)
519 flags
|= CIRCLAUNCH_NEED_UPTIME
;
520 if (hidserv_needs_capacity
)
521 flags
|= CIRCLAUNCH_NEED_CAPACITY
;
522 flags
|= CIRCLAUNCH_IS_INTERNAL
;
524 "Have %d clean circs (%d uptime-internal, %d internal), need"
525 " another hidden service circ.",
526 num
, num_uptime_internal
, num_internal
);
527 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
531 /* Finally, check to see if we still need more circuits to learn
532 * a good build timeout. But if we're close to our max number we
533 * want, don't do another -- we want to leave a few slots open so
534 * we can still build circuits preemptively as needed. */
535 if (num
< MAX_UNUSED_OPEN_CIRCUITS
-2 &&
536 circuit_build_times_needs_circuits_now(&circ_times
)) {
537 flags
= CIRCLAUNCH_NEED_CAPACITY
;
539 "Have %d clean circs need another buildtime test circ.", num
);
540 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, flags
);
545 /** Build a new test circuit every 5 minutes */
546 #define TESTING_CIRCUIT_INTERVAL 300
548 /** This function is called once a second, if router_have_min_dir_info() is
549 * true. Its job is to make sure all services we offer have enough circuits
550 * available. Some services just want enough circuits for current tasks,
551 * whereas others want a minimum set of idle circuits hanging around.
554 circuit_build_needed_circs(time_t now
)
556 static time_t time_to_new_circuit
= 0;
557 or_options_t
*options
= get_options();
559 /* launch a new circ for any pending streams that need one */
560 connection_ap_attach_pending();
562 /* make sure any hidden services have enough intro points */
563 rend_services_introduce();
565 if (time_to_new_circuit
< now
) {
566 circuit_reset_failure_count(1);
567 time_to_new_circuit
= now
+ options
->NewCircuitPeriod
;
568 if (proxy_mode(get_options()))
569 addressmap_clean(now
);
570 circuit_expire_old_circuits(now
);
572 #if 0 /* disable for now, until predict-and-launch-new can cull leftovers */
573 circ
= circuit_get_youngest_clean_open(CIRCUIT_PURPOSE_C_GENERAL
);
574 if (get_options()->RunTesting
&&
576 circ
->timestamp_created
+ TESTING_CIRCUIT_INTERVAL
< now
) {
577 log_fn(LOG_INFO
,"Creating a new testing circuit.");
578 circuit_launch_by_router(CIRCUIT_PURPOSE_C_GENERAL
, NULL
, 0);
582 if (!options
->DisablePredictedCircuits
)
583 circuit_predict_and_launch_new();
586 /** If the stream <b>conn</b> is a member of any of the linked
587 * lists of <b>circ</b>, then remove it from the list.
590 circuit_detach_stream(circuit_t
*circ
, edge_connection_t
*conn
)
592 edge_connection_t
*prevconn
;
597 conn
->cpath_layer
= NULL
; /* make sure we don't keep a stale pointer */
598 conn
->on_circuit
= NULL
;
600 if (CIRCUIT_IS_ORIGIN(circ
)) {
601 origin_circuit_t
*origin_circ
= TO_ORIGIN_CIRCUIT(circ
);
602 if (conn
== origin_circ
->p_streams
) {
603 origin_circ
->p_streams
= conn
->next_stream
;
607 for (prevconn
= origin_circ
->p_streams
;
608 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
609 prevconn
= prevconn
->next_stream
)
611 if (prevconn
&& prevconn
->next_stream
) {
612 prevconn
->next_stream
= conn
->next_stream
;
616 or_circuit_t
*or_circ
= TO_OR_CIRCUIT(circ
);
617 if (conn
== or_circ
->n_streams
) {
618 or_circ
->n_streams
= conn
->next_stream
;
621 if (conn
== or_circ
->resolving_streams
) {
622 or_circ
->resolving_streams
= conn
->next_stream
;
626 for (prevconn
= or_circ
->n_streams
;
627 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
628 prevconn
= prevconn
->next_stream
)
630 if (prevconn
&& prevconn
->next_stream
) {
631 prevconn
->next_stream
= conn
->next_stream
;
635 for (prevconn
= or_circ
->resolving_streams
;
636 prevconn
&& prevconn
->next_stream
&& prevconn
->next_stream
!= conn
;
637 prevconn
= prevconn
->next_stream
)
639 if (prevconn
&& prevconn
->next_stream
) {
640 prevconn
->next_stream
= conn
->next_stream
;
645 log_warn(LD_BUG
,"Edge connection not in circuit's list.");
646 /* Don't give an error here; it's harmless. */
647 tor_fragile_assert();
650 /** If we haven't yet decided on a good timeout value for circuit
651 * building, we close idles circuits aggressively so we can get more
653 #define IDLE_TIMEOUT_WHILE_LEARNING (10*60)
655 /** Find each circuit that has been unused for too long, or dirty
656 * for too long and has no streams on it: mark it for close.
659 circuit_expire_old_circuits(time_t now
)
664 if (circuit_build_times_needs_circuits(&circ_times
)) {
665 /* Circuits should be shorter lived if we need more of them
666 * for learning a good build timeout */
667 cutoff
= now
- IDLE_TIMEOUT_WHILE_LEARNING
;
669 cutoff
= now
- get_options()->CircuitIdleTimeout
;
672 for (circ
= global_circuitlist
; circ
; circ
= circ
->next
) {
673 if (circ
->marked_for_close
|| ! CIRCUIT_IS_ORIGIN(circ
))
675 /* If the circuit has been dirty for too long, and there are no streams
676 * on it, mark it for close.
678 if (circ
->timestamp_dirty
&&
679 circ
->timestamp_dirty
+ get_options()->MaxCircuitDirtiness
< now
&&
680 !TO_ORIGIN_CIRCUIT(circ
)->p_streams
/* nothing attached */ ) {
681 log_debug(LD_CIRC
, "Closing n_circ_id %d (dirty %d secs ago, "
683 circ
->n_circ_id
, (int)(now
- circ
->timestamp_dirty
),
685 circuit_mark_for_close(circ
, END_CIRC_REASON_FINISHED
);
686 } else if (!circ
->timestamp_dirty
&&
687 circ
->state
== CIRCUIT_STATE_OPEN
&&
688 circ
->purpose
== CIRCUIT_PURPOSE_C_GENERAL
) {
689 if (circ
->timestamp_created
< cutoff
) {
691 "Closing circuit that has been unused for %d seconds.",
692 (int)(now
- circ
->timestamp_created
));
693 circuit_mark_for_close(circ
, END_CIRC_REASON_FINISHED
);
699 /** Number of testing circuits we want open before testing our bandwidth. */
700 #define NUM_PARALLEL_TESTING_CIRCS 4
702 /** True iff we've ever had enough testing circuits open to test our
704 static int have_performed_bandwidth_test
= 0;
706 /** Reset have_performed_bandwidth_test, so we'll start building
707 * testing circuits again so we can exercise our bandwidth. */
709 reset_bandwidth_test(void)
711 have_performed_bandwidth_test
= 0;
714 /** Return 1 if we've already exercised our bandwidth, or if we
715 * have fewer than NUM_PARALLEL_TESTING_CIRCS testing circuits
716 * established or on the way. Else return 0.
719 circuit_enough_testing_circs(void)
724 if (have_performed_bandwidth_test
)
727 for (circ
= global_circuitlist
; circ
; circ
= circ
->next
) {
728 if (!circ
->marked_for_close
&& CIRCUIT_IS_ORIGIN(circ
) &&
729 circ
->purpose
== CIRCUIT_PURPOSE_TESTING
&&
730 circ
->state
== CIRCUIT_STATE_OPEN
)
733 return num
>= NUM_PARALLEL_TESTING_CIRCS
;
736 /** A testing circuit has completed. Take whatever stats we want.
737 * Noticing reachability is taken care of in onionskin_answer(),
738 * so there's no need to record anything here. But if we still want
739 * to do the bandwidth test, and we now have enough testing circuits
743 circuit_testing_opened(origin_circuit_t
*circ
)
745 if (have_performed_bandwidth_test
||
746 !check_whether_orport_reachable()) {
747 /* either we've already done everything we want with testing circuits,
748 * or this testing circuit became open due to a fluke, e.g. we picked
749 * a last hop where we already had the connection open due to an
750 * outgoing local circuit. */
751 circuit_mark_for_close(TO_CIRCUIT(circ
), END_CIRC_AT_ORIGIN
);
752 } else if (circuit_enough_testing_circs()) {
753 router_perform_bandwidth_test(NUM_PARALLEL_TESTING_CIRCS
, time(NULL
));
754 have_performed_bandwidth_test
= 1;
756 consider_testing_reachability(1, 0);
759 /** A testing circuit has failed to build. Take whatever stats we want. */
761 circuit_testing_failed(origin_circuit_t
*circ
, int at_last_hop
)
763 if (server_mode(get_options()) && check_whether_orport_reachable())
767 "Our testing circuit (to see if your ORPort is reachable) "
768 "has failed. I'll try again later.");
770 /* These aren't used yet. */
775 /** The circuit <b>circ</b> has just become open. Take the next
776 * step: for rendezvous circuits, we pass circ to the appropriate
777 * function in rendclient or rendservice. For general circuits, we
778 * call connection_ap_attach_pending, which looks for pending streams
779 * that could use circ.
782 circuit_has_opened(origin_circuit_t
*circ
)
784 control_event_circuit_status(circ
, CIRC_EVENT_BUILT
, 0);
786 switch (TO_CIRCUIT(circ
)->purpose
) {
787 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
788 rend_client_rendcirc_has_opened(circ
);
789 connection_ap_attach_pending();
791 case CIRCUIT_PURPOSE_C_INTRODUCING
:
792 rend_client_introcirc_has_opened(circ
);
794 case CIRCUIT_PURPOSE_C_GENERAL
:
795 /* Tell any AP connections that have been waiting for a new
796 * circuit that one is ready. */
797 connection_ap_attach_pending();
799 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
800 /* at Bob, waiting for introductions */
801 rend_service_intro_has_opened(circ
);
803 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
804 /* at Bob, connecting to rend point */
805 rend_service_rendezvous_has_opened(circ
);
807 case CIRCUIT_PURPOSE_TESTING
:
808 circuit_testing_opened(circ
);
811 * This won't happen in normal operation, but might happen if the
812 * controller did it. Just let it slide. */
816 /** Called whenever a circuit could not be successfully built.
819 circuit_build_failed(origin_circuit_t
*circ
)
821 /* we should examine circ and see if it failed because of
822 * the last hop or an earlier hop. then use this info below.
824 int failed_at_last_hop
= 0;
825 /* If the last hop isn't open, and the second-to-last is, we failed
826 * at the last hop. */
828 circ
->cpath
->prev
->state
!= CPATH_STATE_OPEN
&&
829 circ
->cpath
->prev
->prev
->state
== CPATH_STATE_OPEN
) {
830 failed_at_last_hop
= 1;
833 circ
->cpath
->state
!= CPATH_STATE_OPEN
) {
834 /* We failed at the first hop. If there's an OR connection
835 * to blame, blame it. Also, avoid this relay for a while, and
836 * fail any one-hop directory fetches destined for it. */
837 const char *n_conn_id
= circ
->cpath
->extend_info
->identity_digest
;
838 if (circ
->_base
.n_conn
) {
839 or_connection_t
*n_conn
= circ
->_base
.n_conn
;
841 "Our circuit failed to get a response from the first hop "
842 "(%s:%d). I'm going to try to rotate to a better connection.",
843 n_conn
->_base
.address
, n_conn
->_base
.port
);
844 n_conn
->is_bad_for_new_circs
= 1;
847 "Our circuit died before the first hop with no connection");
850 entry_guard_register_connect_status(n_conn_id
, 0, 1, time(NULL
));
851 /* if there are any one-hop streams waiting on this circuit, fail
852 * them now so they can retry elsewhere. */
853 connection_ap_fail_onehop(n_conn_id
, circ
->build_state
);
857 switch (circ
->_base
.purpose
) {
858 case CIRCUIT_PURPOSE_C_GENERAL
:
859 /* If we never built the circuit, note it as a failure. */
860 circuit_increment_failure_count();
861 if (failed_at_last_hop
) {
862 /* Make sure any streams that demand our last hop as their exit
863 * know that it's unlikely to happen. */
864 circuit_discard_optional_exit_enclaves(circ
->cpath
->prev
->extend_info
);
867 case CIRCUIT_PURPOSE_TESTING
:
868 circuit_testing_failed(circ
, failed_at_last_hop
);
870 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
871 /* at Bob, waiting for introductions */
872 if (circ
->_base
.state
!= CIRCUIT_STATE_OPEN
) {
873 circuit_increment_failure_count();
875 /* no need to care here, because bob will rebuild intro
876 * points periodically. */
878 case CIRCUIT_PURPOSE_C_INTRODUCING
:
879 /* at Alice, connecting to intro point */
880 /* Don't increment failure count, since Bob may have picked
881 * the introduction point maliciously */
882 /* Alice will pick a new intro point when this one dies, if
883 * the stream in question still cares. No need to act here. */
885 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
886 /* at Alice, waiting for Bob */
887 circuit_increment_failure_count();
888 /* Alice will pick a new rend point when this one dies, if
889 * the stream in question still cares. No need to act here. */
891 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
892 /* at Bob, connecting to rend point */
893 /* Don't increment failure count, since Alice may have picked
894 * the rendezvous point maliciously */
896 "Couldn't connect to Alice's chosen rend point %s "
898 escaped(build_state_get_exit_nickname(circ
->build_state
)),
899 failed_at_last_hop
?"last":"non-last");
900 rend_service_relaunch_rendezvous(circ
);
903 * This won't happen in normal operation, but might happen if the
904 * controller did it. Just let it slide. */
908 /** Number of consecutive failures so far; should only be touched by
909 * circuit_launch_new and circuit_*_failure_count.
911 static int n_circuit_failures
= 0;
912 /** Before the last time we called circuit_reset_failure_count(), were
913 * there a lot of failures? */
914 static int did_circs_fail_last_period
= 0;
916 /** Don't retry launching a new circuit if we try this many times with no
918 #define MAX_CIRCUIT_FAILURES 5
920 /** Launch a new circuit; see circuit_launch_by_extend_info() for
921 * details on arguments. */
923 circuit_launch_by_router(uint8_t purpose
,
924 routerinfo_t
*exit
, int flags
)
926 origin_circuit_t
*circ
;
927 extend_info_t
*info
= NULL
;
929 info
= extend_info_from_router(exit
);
930 circ
= circuit_launch_by_extend_info(purpose
, info
, flags
);
932 extend_info_free(info
);
936 /** Launch a new circuit with purpose <b>purpose</b> and exit node
937 * <b>extend_info</b> (or NULL to select a random exit node). If flags
938 * contains CIRCLAUNCH_NEED_UPTIME, choose among routers with high uptime. If
939 * CIRCLAUNCH_NEED_CAPACITY is set, choose among routers with high bandwidth.
940 * If CIRCLAUNCH_IS_INTERNAL is true, the last hop need not be an exit node.
941 * If CIRCLAUNCH_ONEHOP_TUNNEL is set, the circuit will have only one hop.
942 * Return the newly allocated circuit on success, or NULL on failure. */
944 circuit_launch_by_extend_info(uint8_t purpose
,
945 extend_info_t
*extend_info
,
948 origin_circuit_t
*circ
;
949 int onehop_tunnel
= (flags
& CIRCLAUNCH_ONEHOP_TUNNEL
) != 0;
951 if (!onehop_tunnel
&& !router_have_minimum_dir_info()) {
952 log_debug(LD_CIRC
,"Haven't fetched enough directory info yet; canceling "
957 if ((extend_info
|| purpose
!= CIRCUIT_PURPOSE_C_GENERAL
) &&
958 purpose
!= CIRCUIT_PURPOSE_TESTING
&& !onehop_tunnel
) {
959 /* see if there are appropriate circs available to cannibalize. */
960 /* XXX if we're planning to add a hop, perhaps we want to look for
961 * internal circs rather than exit circs? -RD */
962 circ
= circuit_find_to_cannibalize(purpose
, extend_info
, flags
);
964 log_info(LD_CIRC
,"Cannibalizing circ '%s' for purpose %d",
965 build_state_get_exit_nickname(circ
->build_state
), purpose
);
966 circ
->_base
.purpose
= purpose
;
967 /* reset the birth date of this circ, else expire_building
968 * will see it and think it's been trying to build since it
970 circ
->_base
.timestamp_created
= time(NULL
);
972 case CIRCUIT_PURPOSE_C_ESTABLISH_REND
:
973 case CIRCUIT_PURPOSE_S_ESTABLISH_INTRO
:
974 /* it's ready right now */
976 case CIRCUIT_PURPOSE_C_INTRODUCING
:
977 case CIRCUIT_PURPOSE_S_CONNECT_REND
:
978 case CIRCUIT_PURPOSE_C_GENERAL
:
979 /* need to add a new hop */
980 tor_assert(extend_info
);
981 if (circuit_extend_to_new_exit(circ
, extend_info
) < 0)
986 "unexpected purpose %d when cannibalizing a circ.",
988 tor_fragile_assert();
995 if (did_circs_fail_last_period
&&
996 n_circuit_failures
> MAX_CIRCUIT_FAILURES
) {
997 /* too many failed circs in a row. don't try. */
998 // log_fn(LOG_INFO,"%d failures so far, not trying.",n_circuit_failures);
1002 /* try a circ. if it fails, circuit_mark_for_close will increment
1003 * n_circuit_failures */
1004 return circuit_establish_circuit(purpose
, extend_info
, flags
);
1007 /** Record another failure at opening a general circuit. When we have
1008 * too many, we'll stop trying for the remainder of this minute.
1011 circuit_increment_failure_count(void)
1013 ++n_circuit_failures
;
1014 log_debug(LD_CIRC
,"n_circuit_failures now %d.",n_circuit_failures
);
1017 /** Reset the failure count for opening general circuits. This means
1018 * we will try MAX_CIRCUIT_FAILURES times more (if necessary) before
1022 circuit_reset_failure_count(int timeout
)
1024 if (timeout
&& n_circuit_failures
> MAX_CIRCUIT_FAILURES
)
1025 did_circs_fail_last_period
= 1;
1027 did_circs_fail_last_period
= 0;
1028 n_circuit_failures
= 0;
1031 /** Find an open circ that we're happy to use for <b>conn</b> and return 1. If
1032 * there isn't one, and there isn't one on the way, launch one and return
1033 * 0. If it will never work, return -1.
1035 * Write the found or in-progress or launched circ into *circp.
1038 circuit_get_open_circ_or_launch(edge_connection_t
*conn
,
1039 uint8_t desired_circuit_purpose
,
1040 origin_circuit_t
**circp
)
1042 origin_circuit_t
*circ
;
1043 int check_exit_policy
;
1044 int need_uptime
, need_internal
;
1046 or_options_t
*options
= get_options();
1050 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
);
1052 conn
->socks_request
->command
== SOCKS_COMMAND_CONNECT
&&
1053 !conn
->use_begindir
&&
1054 !connection_edge_is_rendezvous_stream(conn
);
1055 want_onehop
= conn
->want_onehop
;
1057 need_uptime
= !conn
->want_onehop
&& !conn
->use_begindir
&&
1058 smartlist_string_num_isin(options
->LongLivedPorts
,
1059 conn
->socks_request
->port
);
1060 need_internal
= desired_circuit_purpose
!= CIRCUIT_PURPOSE_C_GENERAL
;
1062 circ
= circuit_get_best(conn
, 1, desired_circuit_purpose
,
1063 need_uptime
, need_internal
);
1067 return 1; /* we're happy */
1070 if (!want_onehop
&& !router_have_minimum_dir_info()) {
1071 if (!connection_get_by_type(CONN_TYPE_DIR
)) {
1072 int severity
= LOG_NOTICE
;
1073 /* FFFF if this is a tunneled directory fetch, don't yell
1074 * as loudly. the user doesn't even know it's happening. */
1075 if (options
->UseBridges
&& bridges_known_but_down()) {
1076 log_fn(severity
, LD_APP
|LD_DIR
,
1077 "Application request when we're believed to be "
1078 "offline. Optimistically trying known bridges again.");
1079 bridges_retry_all();
1080 } else if (!options
->UseBridges
|| any_bridge_descriptors_known()) {
1081 log_fn(severity
, LD_APP
|LD_DIR
,
1082 "Application request when we're believed to be "
1083 "offline. Optimistically trying directory fetches again.");
1084 routerlist_retry_directory_downloads(time(NULL
));
1087 /* the stream will be dealt with when router_have_minimum_dir_info becomes
1088 * 1, or when all directory attempts fail and directory_all_unreachable()
1094 /* Do we need to check exit policy? */
1095 if (check_exit_policy
) {
1096 if (!conn
->chosen_exit_name
) {
1099 if (tor_inet_aton(conn
->socks_request
->address
, &in
))
1100 addr
= ntohl(in
.s_addr
);
1101 if (router_exit_policy_all_routers_reject(addr
,
1102 conn
->socks_request
->port
,
1105 "No Tor server allows exit to %s:%d. Rejecting.",
1106 safe_str_client(conn
->socks_request
->address
),
1107 conn
->socks_request
->port
);
1111 /* XXXX022 Duplicates checks in connection_ap_handshake_attach_circuit */
1112 routerinfo_t
*router
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1113 int opt
= conn
->chosen_exit_optional
;
1114 if (router
&& !connection_ap_can_use_exit(conn
, router
, 0)) {
1115 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1116 "Requested exit point '%s' would refuse request. %s.",
1117 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1119 conn
->chosen_exit_optional
= 0;
1120 tor_free(conn
->chosen_exit_name
);
1122 return circuit_get_open_circ_or_launch(conn
,
1123 desired_circuit_purpose
,
1131 /* is one already on the way? */
1132 circ
= circuit_get_best(conn
, 0, desired_circuit_purpose
,
1133 need_uptime
, need_internal
);
1135 log_debug(LD_CIRC
, "one on the way!");
1137 extend_info_t
*extend_info
=NULL
;
1138 uint8_t new_circ_purpose
;
1140 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
) {
1141 /* need to pick an intro point */
1142 tor_assert(conn
->rend_data
);
1143 extend_info
= rend_client_get_random_intro(conn
->rend_data
);
1146 "No intro points for '%s': re-fetching service descriptor.",
1147 safe_str_client(conn
->rend_data
->onion_address
));
1148 rend_client_refetch_v2_renddesc(conn
->rend_data
);
1149 conn
->_base
.state
= AP_CONN_STATE_RENDDESC_WAIT
;
1152 log_info(LD_REND
,"Chose '%s' as intro point for '%s'.",
1153 extend_info
->nickname
,
1154 safe_str_client(conn
->rend_data
->onion_address
));
1157 /* If we have specified a particular exit node for our
1158 * connection, then be sure to open a circuit to that exit node.
1160 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_GENERAL
) {
1161 if (conn
->chosen_exit_name
) {
1163 int opt
= conn
->chosen_exit_optional
;
1164 r
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1166 extend_info
= extend_info_from_router(r
);
1168 log_debug(LD_DIR
, "considering %d, %s",
1169 want_onehop
, conn
->chosen_exit_name
);
1170 if (want_onehop
&& conn
->chosen_exit_name
[0] == '$') {
1171 /* We're asking for a one-hop circuit to a router that
1172 * we don't have a routerinfo about. Make up an extend_info. */
1173 char digest
[DIGEST_LEN
];
1174 char *hexdigest
= conn
->chosen_exit_name
+1;
1176 if (strlen(hexdigest
) < HEX_DIGEST_LEN
||
1177 base16_decode(digest
,DIGEST_LEN
,hexdigest
,HEX_DIGEST_LEN
)<0) {
1178 log_info(LD_DIR
, "Broken exit digest on tunnel conn. Closing.");
1181 if (tor_addr_from_str(&addr
, conn
->socks_request
->address
) < 0) {
1182 log_info(LD_DIR
, "Broken address %s on tunnel conn. Closing.",
1183 escaped_safe_str_client(conn
->socks_request
->address
));
1186 extend_info
= extend_info_alloc(conn
->chosen_exit_name
+1,
1187 digest
, NULL
, &addr
,
1188 conn
->socks_request
->port
);
1190 /* We will need an onion key for the router, and we
1191 * don't have one. Refuse or relax requirements. */
1192 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1193 "Requested exit point '%s' is not known. %s.",
1194 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1196 conn
->chosen_exit_optional
= 0;
1197 tor_free(conn
->chosen_exit_name
);
1198 /* Try again with no requested exit */
1199 return circuit_get_open_circ_or_launch(conn
,
1200 desired_circuit_purpose
,
1209 if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_REND_JOINED
)
1210 new_circ_purpose
= CIRCUIT_PURPOSE_C_ESTABLISH_REND
;
1211 else if (desired_circuit_purpose
== CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
)
1212 new_circ_purpose
= CIRCUIT_PURPOSE_C_INTRODUCING
;
1214 new_circ_purpose
= desired_circuit_purpose
;
1217 int flags
= CIRCLAUNCH_NEED_CAPACITY
;
1218 if (want_onehop
) flags
|= CIRCLAUNCH_ONEHOP_TUNNEL
;
1219 if (need_uptime
) flags
|= CIRCLAUNCH_NEED_UPTIME
;
1220 if (need_internal
) flags
|= CIRCLAUNCH_IS_INTERNAL
;
1221 circ
= circuit_launch_by_extend_info(new_circ_purpose
, extend_info
,
1225 extend_info_free(extend_info
);
1227 if (desired_circuit_purpose
!= CIRCUIT_PURPOSE_C_GENERAL
) {
1228 /* help predict this next time */
1229 rep_hist_note_used_internal(time(NULL
), need_uptime
, 1);
1231 /* write the service_id into circ */
1232 circ
->rend_data
= rend_data_dup(conn
->rend_data
);
1233 if (circ
->_base
.purpose
== CIRCUIT_PURPOSE_C_ESTABLISH_REND
&&
1234 circ
->_base
.state
== CIRCUIT_STATE_OPEN
)
1235 rend_client_rendcirc_has_opened(circ
);
1241 "No safe circuit (purpose %d) ready for edge "
1242 "connection; delaying.",
1243 desired_circuit_purpose
);
1248 /** Return true iff <b>crypt_path</b> is one of the crypt_paths for
1251 cpath_is_on_circuit(origin_circuit_t
*circ
, crypt_path_t
*crypt_path
)
1253 crypt_path_t
*cpath
, *cpath_next
= NULL
;
1254 for (cpath
= circ
->cpath
; cpath_next
!= circ
->cpath
; cpath
= cpath_next
) {
1255 cpath_next
= cpath
->next
;
1256 if (crypt_path
== cpath
)
1262 /** Attach the AP stream <b>apconn</b> to circ's linked list of
1263 * p_streams. Also set apconn's cpath_layer to <b>cpath</b>, or to the last
1264 * hop in circ's cpath if <b>cpath</b> is NULL.
1267 link_apconn_to_circ(edge_connection_t
*apconn
, origin_circuit_t
*circ
,
1268 crypt_path_t
*cpath
)
1270 /* add it into the linked list of streams on this circuit */
1271 log_debug(LD_APP
|LD_CIRC
, "attaching new conn to circ. n_circ_id %d.",
1272 circ
->_base
.n_circ_id
);
1273 /* reset it, so we can measure circ timeouts */
1274 apconn
->_base
.timestamp_lastread
= time(NULL
);
1275 apconn
->next_stream
= circ
->p_streams
;
1276 apconn
->on_circuit
= TO_CIRCUIT(circ
);
1277 /* assert_connection_ok(conn, time(NULL)); */
1278 circ
->p_streams
= apconn
;
1280 if (cpath
) { /* we were given one; use it */
1281 tor_assert(cpath_is_on_circuit(circ
, cpath
));
1282 apconn
->cpath_layer
= cpath
;
1283 } else { /* use the last hop in the circuit */
1284 tor_assert(circ
->cpath
);
1285 tor_assert(circ
->cpath
->prev
);
1286 tor_assert(circ
->cpath
->prev
->state
== CPATH_STATE_OPEN
);
1287 apconn
->cpath_layer
= circ
->cpath
->prev
;
1291 /** If an exit wasn't specifically chosen, save the history for future
1294 consider_recording_trackhost(edge_connection_t
*conn
, origin_circuit_t
*circ
)
1296 int found_needle
= 0;
1297 or_options_t
*options
= get_options();
1300 char fp
[HEX_DIGEST_LEN
+1];
1302 /* Search the addressmap for this conn's destination. */
1303 /* If he's not in the address map.. */
1304 if (!options
->TrackHostExits
||
1305 addressmap_have_mapping(conn
->socks_request
->address
,
1306 options
->TrackHostExitsExpire
))
1307 return; /* nothing to track, or already mapped */
1309 SMARTLIST_FOREACH(options
->TrackHostExits
, const char *, cp
, {
1310 if (cp
[0] == '.') { /* match end */
1311 if (cp
[1] == '\0' ||
1312 !strcasecmpend(conn
->socks_request
->address
, cp
) ||
1313 !strcasecmp(conn
->socks_request
->address
, &cp
[1]))
1315 } else if (strcasecmp(cp
, conn
->socks_request
->address
) == 0) {
1320 if (!found_needle
|| !circ
->build_state
->chosen_exit
)
1323 /* write down the fingerprint of the chosen exit, not the nickname,
1324 * because the chosen exit might not be named. */
1325 base16_encode(fp
, sizeof(fp
),
1326 circ
->build_state
->chosen_exit
->identity_digest
, DIGEST_LEN
);
1328 /* Add this exit/hostname pair to the addressmap. */
1329 len
= strlen(conn
->socks_request
->address
) + 1 /* '.' */ +
1330 strlen(fp
) + 1 /* '.' */ +
1331 strlen("exit") + 1 /* '\0' */;
1332 new_address
= tor_malloc(len
);
1334 tor_snprintf(new_address
, len
, "%s.%s.exit",
1335 conn
->socks_request
->address
, fp
);
1337 addressmap_register(conn
->socks_request
->address
, new_address
,
1338 time(NULL
) + options
->TrackHostExitsExpire
,
1339 ADDRMAPSRC_TRACKEXIT
);
1342 /** Attempt to attach the connection <b>conn</b> to <b>circ</b>, and send a
1343 * begin or resolve cell as appropriate. Return values are as for
1344 * connection_ap_handshake_attach_circuit. The stream will exit from the hop
1345 * indicated by <b>cpath</b>, or from the last hop in circ's cpath if
1346 * <b>cpath</b> is NULL. */
1348 connection_ap_handshake_attach_chosen_circuit(edge_connection_t
*conn
,
1349 origin_circuit_t
*circ
,
1350 crypt_path_t
*cpath
)
1353 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
||
1354 conn
->_base
.state
== AP_CONN_STATE_CONTROLLER_WAIT
);
1355 tor_assert(conn
->socks_request
);
1357 tor_assert(circ
->_base
.state
== CIRCUIT_STATE_OPEN
);
1359 conn
->_base
.state
= AP_CONN_STATE_CIRCUIT_WAIT
;
1361 if (!circ
->_base
.timestamp_dirty
)
1362 circ
->_base
.timestamp_dirty
= time(NULL
);
1364 link_apconn_to_circ(conn
, circ
, cpath
);
1365 tor_assert(conn
->socks_request
);
1366 if (conn
->socks_request
->command
== SOCKS_COMMAND_CONNECT
) {
1367 if (!conn
->use_begindir
)
1368 consider_recording_trackhost(conn
, circ
);
1369 if (connection_ap_handshake_send_begin(conn
) < 0)
1372 if (connection_ap_handshake_send_resolve(conn
) < 0)
1379 /** Try to find a safe live circuit for CONN_TYPE_AP connection conn. If
1380 * we don't find one: if conn cannot be handled by any known nodes,
1381 * warn and return -1 (conn needs to die, and is maybe already marked);
1382 * else launch new circuit (if necessary) and return 0.
1383 * Otherwise, associate conn with a safe live circuit, do the
1384 * right next step, and return 1.
1386 /* XXXX this function should mark for close whenever it returns -1;
1387 * its callers shouldn't have to worry about that. */
1389 connection_ap_handshake_attach_circuit(edge_connection_t
*conn
)
1396 tor_assert(conn
->_base
.state
== AP_CONN_STATE_CIRCUIT_WAIT
);
1397 tor_assert(conn
->socks_request
);
1398 want_onehop
= conn
->want_onehop
;
1400 conn_age
= (int)(time(NULL
) - conn
->_base
.timestamp_created
);
1402 if (conn_age
>= get_options()->SocksTimeout
) {
1403 int severity
= (tor_addr_is_null(&conn
->_base
.addr
) && !conn
->_base
.port
) ?
1404 LOG_INFO
: LOG_NOTICE
;
1405 log_fn(severity
, LD_APP
,
1406 "Tried for %d seconds to get a connection to %s:%d. Giving up.",
1407 conn_age
, safe_str_client(conn
->socks_request
->address
),
1408 conn
->socks_request
->port
);
1412 if (!connection_edge_is_rendezvous_stream(conn
)) { /* we're a general conn */
1413 origin_circuit_t
*circ
=NULL
;
1415 if (conn
->chosen_exit_name
) {
1416 routerinfo_t
*router
= router_get_by_nickname(conn
->chosen_exit_name
, 1);
1417 int opt
= conn
->chosen_exit_optional
;
1418 if (!router
&& !want_onehop
) {
1419 /* We ran into this warning when trying to extend a circuit to a
1420 * hidden service directory for which we didn't have a router
1421 * descriptor. See flyspray task 767 for more details. We should
1422 * keep this in mind when deciding to use BEGIN_DIR cells for other
1423 * directory requests as well. -KL*/
1424 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1425 "Requested exit point '%s' is not known. %s.",
1426 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1428 conn
->chosen_exit_optional
= 0;
1429 tor_free(conn
->chosen_exit_name
);
1434 if (router
&& !connection_ap_can_use_exit(conn
, router
, 0)) {
1435 log_fn(opt
? LOG_INFO
: LOG_WARN
, LD_APP
,
1436 "Requested exit point '%s' would refuse request. %s.",
1437 conn
->chosen_exit_name
, opt
? "Trying others" : "Closing");
1439 conn
->chosen_exit_optional
= 0;
1440 tor_free(conn
->chosen_exit_name
);
1447 /* find the circuit that we should use, if there is one. */
1448 retval
= circuit_get_open_circ_or_launch(
1449 conn
, CIRCUIT_PURPOSE_C_GENERAL
, &circ
);
1450 if (retval
< 1) // XXX021 if we totally fail, this still returns 0 -RD
1453 log_debug(LD_APP
|LD_CIRC
,
1454 "Attaching apconn to circ %d (stream %d sec old).",
1455 circ
->_base
.n_circ_id
, conn_age
);
1456 /* print the circ's path, so people can figure out which circs are
1458 circuit_log_path(LOG_INFO
,LD_APP
|LD_CIRC
,circ
);
1460 /* We have found a suitable circuit for our conn. Hurray. */
1461 return connection_ap_handshake_attach_chosen_circuit(conn
, circ
, NULL
);
1463 } else { /* we're a rendezvous conn */
1464 origin_circuit_t
*rendcirc
=NULL
, *introcirc
=NULL
;
1466 tor_assert(!conn
->cpath_layer
);
1468 /* start by finding a rendezvous circuit for us */
1470 retval
= circuit_get_open_circ_or_launch(
1471 conn
, CIRCUIT_PURPOSE_C_REND_JOINED
, &rendcirc
);
1472 if (retval
< 0) return -1; /* failed */
1475 tor_assert(rendcirc
);
1476 /* one is already established, attach */
1478 "rend joined circ %d already here. attaching. "
1479 "(stream %d sec old)",
1480 rendcirc
->_base
.n_circ_id
, conn_age
);
1481 /* Mark rendezvous circuits as 'newly dirty' every time you use
1482 * them, since the process of rebuilding a rendezvous circ is so
1483 * expensive. There is a tradeoff between linkability and
1484 * feasibility, at this point.
1486 rendcirc
->_base
.timestamp_dirty
= time(NULL
);
1487 link_apconn_to_circ(conn
, rendcirc
, NULL
);
1488 if (connection_ap_handshake_send_begin(conn
) < 0)
1489 return 0; /* already marked, let them fade away */
1493 if (rendcirc
&& (rendcirc
->_base
.purpose
==
1494 CIRCUIT_PURPOSE_C_REND_READY_INTRO_ACKED
)) {
1496 "pending-join circ %d already here, with intro ack. "
1497 "Stalling. (stream %d sec old)",
1498 rendcirc
->_base
.n_circ_id
, conn_age
);
1502 /* it's on its way. find an intro circ. */
1503 retval
= circuit_get_open_circ_or_launch(
1504 conn
, CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT
, &introcirc
);
1505 if (retval
< 0) return -1; /* failed */
1508 /* one has already sent the intro. keep waiting. */
1509 circuit_t
*c
= NULL
;
1510 tor_assert(introcirc
);
1511 log_info(LD_REND
, "Intro circ %d present and awaiting ack (rend %d). "
1512 "Stalling. (stream %d sec old)",
1513 introcirc
->_base
.n_circ_id
,
1514 rendcirc
? rendcirc
->_base
.n_circ_id
: 0,
1516 /* abort parallel intro circs, if any */
1517 for (c
= global_circuitlist
; c
; c
= c
->next
) {
1518 if (c
->purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
&&
1519 !c
->marked_for_close
&& CIRCUIT_IS_ORIGIN(c
)) {
1520 origin_circuit_t
*oc
= TO_ORIGIN_CIRCUIT(c
);
1521 if (oc
->rend_data
&&
1522 !rend_cmp_service_ids(conn
->rend_data
->onion_address
,
1523 oc
->rend_data
->onion_address
)) {
1524 log_info(LD_REND
|LD_CIRC
, "Closing introduction circuit that we "
1525 "built in parallel.");
1526 circuit_mark_for_close(c
, END_CIRC_REASON_TIMEOUT
);
1533 /* now rendcirc and introcirc are each either undefined or not finished */
1535 if (rendcirc
&& introcirc
&&
1536 rendcirc
->_base
.purpose
== CIRCUIT_PURPOSE_C_REND_READY
) {
1538 "ready rend circ %d already here (no intro-ack yet on "
1539 "intro %d). (stream %d sec old)",
1540 rendcirc
->_base
.n_circ_id
,
1541 introcirc
->_base
.n_circ_id
, conn_age
);
1543 tor_assert(introcirc
->_base
.purpose
== CIRCUIT_PURPOSE_C_INTRODUCING
);
1544 if (introcirc
->_base
.state
== CIRCUIT_STATE_OPEN
) {
1545 log_info(LD_REND
,"found open intro circ %d (rend %d); sending "
1546 "introduction. (stream %d sec old)",
1547 introcirc
->_base
.n_circ_id
, rendcirc
->_base
.n_circ_id
,
1549 if (rend_client_send_introduction(introcirc
, rendcirc
) < 0) {
1552 rendcirc
->_base
.timestamp_dirty
= time(NULL
);
1553 introcirc
->_base
.timestamp_dirty
= time(NULL
);
1554 assert_circuit_ok(TO_CIRCUIT(rendcirc
));
1555 assert_circuit_ok(TO_CIRCUIT(introcirc
));
1560 log_info(LD_REND
, "Intro (%d) and rend (%d) circs are not both ready. "
1561 "Stalling conn. (%d sec old)",
1562 introcirc
? introcirc
->_base
.n_circ_id
: 0,
1563 rendcirc
? rendcirc
->_base
.n_circ_id
: 0, conn_age
);